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diff --git a/doc/rfc/rfc2744.txt b/doc/rfc/rfc2744.txt new file mode 100644 index 0000000..7f0c619 --- /dev/null +++ b/doc/rfc/rfc2744.txt @@ -0,0 +1,5659 @@ + + + + + + +Network Working Group J. Wray +Request for Comments: 2744 Iris Associates +Obsoletes: 1509 January 2000 +Category: Standards Track + + + Generic Security Service API Version 2 : C-bindings + +Status of this Memo + + This document specifies an Internet standards track protocol for the + Internet community, and requests discussion and suggestions for + improvements. Please refer to the current edition of the "Internet + Official Protocol Standards" (STD 1) for the standardization state + and status of this protocol. Distribution of this memo is unlimited. + +Copyright Notice + + Copyright (C) The Internet Society (2000). All Rights Reserved. + +Abstract + + This document specifies C language bindings for Version 2, Update 1 + of the Generic Security Service Application Program Interface (GSS- + API), which is described at a language-independent conceptual level + in RFC-2743 [GSSAPI]. It obsoletes RFC-1509, making specific + incremental changes in response to implementation experience and + liaison requests. It is intended, therefore, that this memo or a + successor version thereof will become the basis for subsequent + progression of the GSS-API specification on the standards track. + + The Generic Security Service Application Programming Interface + provides security services to its callers, and is intended for + implementation atop a variety of underlying cryptographic mechanisms. + Typically, GSS-API callers will be application protocols into which + security enhancements are integrated through invocation of services + provided by the GSS-API. The GSS-API allows a caller application to + authenticate a principal identity associated with a peer application, + to delegate rights to a peer, and to apply security services such as + confidentiality and integrity on a per-message basis. + + + + + + + + + + + +Wray Standards Track [Page 1] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +1. Introduction + + The Generic Security Service Application Programming Interface + [GSSAPI] provides security services to calling applications. It + allows a communicating application to authenticate the user + associated with another application, to delegate rights to another + application, and to apply security services such as confidentiality + and integrity on a per-message basis. + + There are four stages to using the GSS-API: + + a) The application acquires a set of credentials with which it may + prove its identity to other processes. The application's + credentials vouch for its global identity, which may or may not be + related to any local username under which it may be running. + + b) A pair of communicating applications establish a joint security + context using their credentials. The security context is a pair + of GSS-API data structures that contain shared state information, + which is required in order that per-message security services may + be provided. Examples of state that might be shared between + applications as part of a security context are cryptographic keys, + and message sequence numbers. As part of the establishment of a + security context, the context initiator is authenticated to the + responder, and may require that the responder is authenticated in + turn. The initiator may optionally give the responder the right + to initiate further security contexts, acting as an agent or + delegate of the initiator. This transfer of rights is termed + delegation, and is achieved by creating a set of credentials, + similar to those used by the initiating application, but which may + be used by the responder. + + To establish and maintain the shared information that makes up the + security context, certain GSS-API calls will return a token data + structure, which is an opaque data type that may contain + cryptographically protected data. The caller of such a GSS-API + routine is responsible for transferring the token to the peer + application, encapsulated if necessary in an application- + application protocol. On receipt of such a token, the peer + application should pass it to a corresponding GSS-API routine + which will decode the token and extract the information, updating + the security context state information accordingly. + + + + + + + + + +Wray Standards Track [Page 2] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + c) Per-message services are invoked to apply either: + + integrity and data origin authentication, or confidentiality, + integrity and data origin authentication to application data, + which are treated by GSS-API as arbitrary octet-strings. An + application transmitting a message that it wishes to protect will + call the appropriate GSS-API routine (gss_get_mic or gss_wrap) to + apply protection, specifying the appropriate security context, and + send the resulting token to the receiving application. The + receiver will pass the received token (and, in the case of data + protected by gss_get_mic, the accompanying message-data) to the + corresponding decoding routine (gss_verify_mic or gss_unwrap) to + remove the protection and validate the data. + + d) At the completion of a communications session (which may extend + across several transport connections), each application calls a + GSS-API routine to delete the security context. Multiple contexts + may also be used (either successively or simultaneously) within a + single communications association, at the option of the + applications. + +2. GSS-API Routines + + This section lists the routines that make up the GSS-API, and + offers a brief description of the purpose of each routine. + Detailed descriptions of each routine are listed in alphabetical + order in section 5. + + Table 2-1 GSS-API Credential-management Routines + + Routine Section Function + ------- ------- -------- + gss_acquire_cred 5.2 Assume a global identity; Obtain + a GSS-API credential handle for + pre-existing credentials. + gss_add_cred 5.3 Construct credentials + incrementally + gss_inquire_cred 5.21 Obtain information about a + credential + gss_inquire_cred_by_mech 5.22 Obtain per-mechanism information + about a credential. + gss_release_cred 5.27 Discard a credential handle. + + + + + + + + + +Wray Standards Track [Page 3] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Table 2-2 GSS-API Context-Level Routines + + Routine Section Function + ------- ------- -------- + gss_init_sec_context 5.19 Initiate a security context with + a peer application + gss_accept_sec_context 5.1 Accept a security context + initiated by a + peer application + gss_delete_sec_context 5.9 Discard a security context + gss_process_context_token 5.25 Process a token on a security + context from a peer application + gss_context_time 5.7 Determine for how long a context + will remain valid + gss_inquire_context 5.20 Obtain information about a + security context + gss_wrap_size_limit 5.34 Determine token-size limit for + gss_wrap on a context + gss_export_sec_context 5.14 Transfer a security context to + another process + gss_import_sec_context 5.17 Import a transferred context + + + Table 2-3 GSS-API Per-message Routines + + Routine Section Function + ------- ------- -------- + gss_get_mic 5.15 Calculate a cryptographic message + integrity code (MIC) for a + message; integrity service + gss_verify_mic 5.32 Check a MIC against a message; + verify integrity of a received + message + gss_wrap 5.33 Attach a MIC to a message, and + optionally encrypt the message + content; + confidentiality service + gss_unwrap 5.31 Verify a message with attached + MIC, and decrypt message content + if necessary. + + + + + + + + + + + +Wray Standards Track [Page 4] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Table 2-4 GSS-API Name manipulation Routines + + Routine Section Function + ------- ------- -------- + gss_import_name 5.16 Convert a contiguous string name + to internal-form + gss_display_name 5.10 Convert internal-form name to + text + gss_compare_name 5.6 Compare two internal-form names + + gss_release_name 5.28 Discard an internal-form name + gss_inquire_names_for_mech 5.24 List the name-types supported by + the specified mechanism + gss_inquire_mechs_for_name 5.23 List mechanisms that support the + specified name-type + gss_canonicalize_name 5.5 Convert an internal name to an MN + gss_export_name 5.13 Convert an MN to export form + gss_duplicate_name 5.12 Create a copy of an internal name + + + Table 2-5 GSS-API Miscellaneous Routines + + Routine Section Function + ------- ------- -------- + gss_add_oid_set_member 5.4 Add an object identifier to + a set + gss_display_status 5.11 Convert a GSS-API status code + to text + gss_indicate_mechs 5.18 Determine available underlying + authentication mechanisms + gss_release_buffer 5.26 Discard a buffer + gss_release_oid_set 5.29 Discard a set of object + identifiers + gss_create_empty_oid_set 5.8 Create a set containing no + object identifiers + gss_test_oid_set_member 5.30 Determines whether an object + identifier is a member of a set. + + Individual GSS-API implementations may augment these routines by + providing additional mechanism-specific routines if required + functionality is not available from the generic forms. Applications + are encouraged to use the generic routines wherever possible on + portability grounds. + + + + + + + + +Wray Standards Track [Page 5] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +3. Data Types and Calling Conventions + + The following conventions are used by the GSS-API C-language + bindings: + +3.1. Integer types + + GSS-API uses the following integer data type: + + OM_uint32 32-bit unsigned integer + + Where guaranteed minimum bit-count is important, this portable data + type is used by the GSS-API routine definitions. Individual GSS-API + implementations will include appropriate typedef definitions to map + this type onto a built-in data type. If the platform supports the + X/Open xom.h header file, the OM_uint32 definition contained therein + should be used; the GSS-API header file in Appendix A contains logic + that will detect the prior inclusion of xom.h, and will not attempt + to re-declare OM_uint32. If the X/Open header file is not available + on the platform, the GSS-API implementation should use the smallest + natural unsigned integer type that provides at least 32 bits of + precision. + +3.2. String and similar data + + Many of the GSS-API routines take arguments and return values that + describe contiguous octet-strings. All such data is passed between + the GSS-API and the caller using the gss_buffer_t data type. This + data type is a pointer to a buffer descriptor, which consists of a + length field that contains the total number of bytes in the datum, + and a value field which contains a pointer to the actual datum: + + typedef struct gss_buffer_desc_struct { + size_t length; + void *value; + } gss_buffer_desc, *gss_buffer_t; + + Storage for data returned to the application by a GSS-API routine + using the gss_buffer_t conventions is allocated by the GSS-API + routine. The application may free this storage by invoking the + gss_release_buffer routine. Allocation of the gss_buffer_desc object + is always the responsibility of the application; unused + gss_buffer_desc objects may be initialized to the value + GSS_C_EMPTY_BUFFER. + + + + + + + +Wray Standards Track [Page 6] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +3.2.1. Opaque data types + + Certain multiple-word data items are considered opaque data types at + the GSS-API, because their internal structure has no significance + either to the GSS-API or to the caller. Examples of such opaque data + types are the input_token parameter to gss_init_sec_context (which is + opaque to the caller), and the input_message parameter to gss_wrap + (which is opaque to the GSS-API). Opaque data is passed between the + GSS-API and the application using the gss_buffer_t datatype. + +3.2.2. Character strings + + Certain multiple-word data items may be regarded as simple ISO + Latin-1 character strings. Examples are the printable strings passed + to gss_import_name via the input_name_buffer parameter. Some GSS-API + routines also return character strings. All such character strings + are passed between the application and the GSS-API implementation + using the gss_buffer_t datatype, which is a pointer to a + gss_buffer_desc object. + + When a gss_buffer_desc object describes a printable string, the + length field of the gss_buffer_desc should only count printable + characters within the string. In particular, a trailing NUL + character should NOT be included in the length count, nor should + either the GSS-API implementation or the application assume the + presence of an uncounted trailing NUL. + +3.3. Object Identifiers + + Certain GSS-API procedures take parameters of the type gss_OID, or + Object identifier. This is a type containing ISO-defined tree- + structured values, and is used by the GSS-API caller to select an + underlying security mechanism and to specify namespaces. A value of + type gss_OID has the following structure: + + typedef struct gss_OID_desc_struct { + OM_uint32 length; + void *elements; + } gss_OID_desc, *gss_OID; + + The elements field of this structure points to the first byte of an + octet string containing the ASN.1 BER encoding of the value portion + of the normal BER TLV encoding of the gss_OID. The length field + contains the number of bytes in this value. For example, the gss_OID + value corresponding to {iso(1) identified-organization(3) icd- + ecma(12) member-company(2) dec(1011) cryptoAlgorithms(7) DASS(5)}, + meaning the DASS X.509 authentication mechanism, has a length field + of 7 and an elements field pointing to seven octets containing the + + + +Wray Standards Track [Page 7] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + following octal values: 53,14,2,207,163,7,5. GSS-API implementations + should provide constant gss_OID values to allow applications to + request any supported mechanism, although applications are encouraged + on portability grounds to accept the default mechanism. gss_OID + values should also be provided to allow applications to specify + particular name types (see section 3.10). Applications should treat + gss_OID_desc values returned by GSS-API routines as read-only. In + particular, the application should not attempt to deallocate them + with free(). The gss_OID_desc datatype is equivalent to the X/Open + OM_object_identifier datatype[XOM]. + +3.4. Object Identifier Sets + + Certain GSS-API procedures take parameters of the type gss_OID_set. + This type represents one or more object identifiers (section 2.3). A + gss_OID_set object has the following structure: + + typedef struct gss_OID_set_desc_struct { + size_t count; + gss_OID elements; + } gss_OID_set_desc, *gss_OID_set; + + The count field contains the number of OIDs within the set. The + elements field is a pointer to an array of gss_OID_desc objects, each + of which describes a single OID. gss_OID_set values are used to name + the available mechanisms supported by the GSS-API, to request the use + of specific mechanisms, and to indicate which mechanisms a given + credential supports. + + All OID sets returned to the application by GSS-API are dynamic + objects (the gss_OID_set_desc, the "elements" array of the set, and + the "elements" array of each member OID are all dynamically + allocated), and this storage must be deallocated by the application + using the gss_release_oid_set() routine. + +3.5. Credentials + + A credential handle is a caller-opaque atomic datum that identifies a + GSS-API credential data structure. It is represented by the caller- + opaque type gss_cred_id_t, which should be implemented as a pointer + or arithmetic type. If a pointer implementation is chosen, care must + be taken to ensure that two gss_cred_id_t values may be compared with + the == operator. + + GSS-API credentials can contain mechanism-specific principal + authentication data for multiple mechanisms. A GSS-API credential is + composed of a set of credential-elements, each of which is applicable + to a single mechanism. A credential may contain at most one + + + +Wray Standards Track [Page 8] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + credential-element for each supported mechanism. A credential-element + identifies the data needed by a single mechanism to authenticate a + single principal, and conceptually contains two credential-references + that describe the actual mechanism-specific authentication data, one + to be used by GSS-API for initiating contexts, and one to be used + for accepting contexts. For mechanisms that do not distinguish + between acceptor and initiator credentials, both references would + point to the same underlying mechanism-specific authentication data. + + Credentials describe a set of mechanism-specific principals, and give + their holder the ability to act as any of those principals. All + principal identities asserted by a single GSS-API credential should + belong to the same entity, although enforcement of this property is + an implementation-specific matter. The GSS-API does not make the + actual credentials available to applications; instead a credential + handle is used to identify a particular credential, held internally + by GSS-API. The combination of GSS-API credential handle and + mechanism identifies the principal whose identity will be asserted by + the credential when used with that mechanism. + + The gss_init_sec_context and gss_accept_sec_context routines allow + the value GSS_C_NO_CREDENTIAL to be specified as their credential + handle parameter. This special credential-handle indicates a desire + by the application to act as a default principal. While individual + GSS-API implementations are free to determine such default behavior + as appropriate to the mechanism, the following default behavior by + these routines is recommended for portability: + + gss_init_sec_context + + 1) If there is only a single principal capable of initiating + security contexts for the chosen mechanism that the application + is authorized to act on behalf of, then that principal shall be + used, otherwise + + 2) If the platform maintains a concept of a default network- + identity for the chosen mechanism, and if the application is + authorized to act on behalf of that identity for the purpose of + initiating security contexts, then the principal corresponding + to that identity shall be used, otherwise + + 3) If the platform maintains a concept of a default local + identity, and provides a means to map local identities into + network-identities for the chosen mechanism, and if the + application is authorized to act on behalf of the network- + identity image of the default local identity for the purpose of + + + + + +Wray Standards Track [Page 9] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + initiating security contexts using the chosen mechanism, then + the principal corresponding to that identity shall be used, + otherwise + + 4) A user-configurable default identity should be used. + + gss_accept_sec_context + + 1) If there is only a single authorized principal identity capable + of accepting security contexts for the chosen mechanism, then + that principal shall be used, otherwise + + 2) If the mechanism can determine the identity of the target + principal by examining the context-establishment token, and if + the accepting application is authorized to act as that + principal for the purpose of accepting security contexts using + the chosen mechanism, then that principal identity shall be + used, otherwise + + 3) If the mechanism supports context acceptance by any principal, + and if mutual authentication was not requested, any principal + that the application is authorized to accept security contexts + under using the chosen mechanism may be used, otherwise + + 4)A user-configurable default identity shall be used. + + The purpose of the above rules is to allow security contexts to be + established by both initiator and acceptor using the default behavior + wherever possible. Applications requesting default behavior are + likely to be more portable across mechanisms and platforms than ones + that use gss_acquire_cred to request a specific identity. + +3.6. Contexts + + The gss_ctx_id_t data type contains a caller-opaque atomic value that + identifies one end of a GSS-API security context. It should be + implemented as a pointer or arithmetic type. If a pointer type is + chosen, care should be taken to ensure that two gss_ctx_id_t values + may be compared with the == operator. + + The security context holds state information about each end of a peer + communication, including cryptographic state information. + + + + + + + + + +Wray Standards Track [Page 10] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +3.7. Authentication tokens + + A token is a caller-opaque type that GSS-API uses to maintain + synchronization between the context data structures at each end of a + GSS-API security context. The token is a cryptographically protected + octet-string, generated by the underlying mechanism at one end of a + GSS-API security context for use by the peer mechanism at the other + end. Encapsulation (if required) and transfer of the token are the + responsibility of the peer applications. A token is passed between + the GSS-API and the application using the gss_buffer_t conventions. + +3.8. Interprocess tokens + + Certain GSS-API routines are intended to transfer data between + processes in multi-process programs. These routines use a caller- + opaque octet-string, generated by the GSS-API in one process for use + by the GSS-API in another process. The calling application is + responsible for transferring such tokens between processes in an OS- + specific manner. Note that, while GSS-API implementors are + encouraged to avoid placing sensitive information within interprocess + tokens, or to cryptographically protect them, many implementations + will be unable to avoid placing key material or other sensitive data + within them. It is the application's responsibility to ensure that + interprocess tokens are protected in transit, and transferred only to + processes that are trustworthy. An interprocess token is passed + between the GSS-API and the application using the gss_buffer_t + conventions. + +3.9. Status values + + Every GSS-API routine returns two distinct values to report status + information to the caller: GSS status codes and Mechanism status + codes. + +3.9.1. GSS status codes + + GSS-API routines return GSS status codes as their OM_uint32 function + value. These codes indicate errors that are independent of the + underlying mechanism(s) used to provide the security service. The + errors that can be indicated via a GSS status code are either generic + API routine errors (errors that are defined in the GSS-API + specification) or calling errors (errors that are specific to these + language bindings). + + A GSS status code can indicate a single fatal generic API error from + the routine and a single calling error. In addition, supplementary + status information may be indicated via the setting of bits in the + supplementary info field of a GSS status code. + + + +Wray Standards Track [Page 11] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + These errors are encoded into the 32-bit GSS status code as follows: + + MSB LSB + |------------------------------------------------------------| + | Calling Error | Routine Error | Supplementary Info | + |------------------------------------------------------------| + Bit 31 24 23 16 15 0 + + Hence if a GSS-API routine returns a GSS status code whose upper 16 + bits contain a non-zero value, the call failed. If the calling error + field is non-zero, the invoking application's call of the routine was + erroneous. Calling errors are defined in table 5-1. If the routine + error field is non-zero, the routine failed for one of the routine- + specific reasons listed below in table 5-2. Whether or not the upper + 16 bits indicate a failure or a success, the routine may indicate + additional information by setting bits in the supplementary info + field of the status code. The meaning of individual bits is listed + below in table 5-3. + + Table 3-1 Calling Errors + + Name Value in field Meaning + ---- -------------- ------- + GSS_S_CALL_INACCESSIBLE_READ 1 A required input parameter + could not be read + GSS_S_CALL_INACCESSIBLE_WRITE 2 A required output parameter + could not be written. + GSS_S_CALL_BAD_STRUCTURE 3 A parameter was malformed + + + + + + + + + + + + + + + + + + + + + + + +Wray Standards Track [Page 12] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Table 3-2 Routine Errors + + Name Value in field Meaning + ---- -------------- ------- + GSS_S_BAD_MECH 1 An unsupported mechanism + was requested + GSS_S_BAD_NAME 2 An invalid name was + supplied + GSS_S_BAD_NAMETYPE 3 A supplied name was of an + unsupported type + GSS_S_BAD_BINDINGS 4 Incorrect channel bindings + were supplied + GSS_S_BAD_STATUS 5 An invalid status code was + supplied + GSS_S_BAD_MIC GSS_S_BAD_SIG 6 A token had an invalid MIC + GSS_S_NO_CRED 7 No credentials were + supplied, or the + credentials were + unavailable or + inaccessible. + GSS_S_NO_CONTEXT 8 No context has been + established + GSS_S_DEFECTIVE_TOKEN 9 A token was invalid + GSS_S_DEFECTIVE_CREDENTIAL 10 A credential was invalid + GSS_S_CREDENTIALS_EXPIRED 11 The referenced credentials + have expired + GSS_S_CONTEXT_EXPIRED 12 The context has expired + GSS_S_FAILURE 13 Miscellaneous failure (see + text) + GSS_S_BAD_QOP 14 The quality-of-protection + requested could not be + provided + GSS_S_UNAUTHORIZED 15 The operation is forbidden + by local security policy + GSS_S_UNAVAILABLE 16 The operation or option is + unavailable + GSS_S_DUPLICATE_ELEMENT 17 The requested credential + element already exists + GSS_S_NAME_NOT_MN 18 The provided name was not a + mechanism name + + + + + + + + + + + +Wray Standards Track [Page 13] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Table 3-3 Supplementary Status Bits + + Name Bit Number Meaning + ---- ---------- ------- + GSS_S_CONTINUE_NEEDED 0 (LSB) Returned only by + gss_init_sec_context or + gss_accept_sec_context. The + routine must be called again + to complete its function. + See routine documentation for + detailed description + GSS_S_DUPLICATE_TOKEN 1 The token was a duplicate of + an earlier token + GSS_S_OLD_TOKEN 2 The token's validity period + has expired + GSS_S_UNSEQ_TOKEN 3 A later token has already been + processed + GSS_S_GAP_TOKEN 4 An expected per-message token + was not received + + The routine documentation also uses the name GSS_S_COMPLETE, which is + a zero value, to indicate an absence of any API errors or + supplementary information bits. + + All GSS_S_xxx symbols equate to complete OM_uint32 status codes, + rather than to bitfield values. For example, the actual value of the + symbol GSS_S_BAD_NAMETYPE (value 3 in the routine error field) is + 3<<16. The macros GSS_CALLING_ERROR(), GSS_ROUTINE_ERROR() and + GSS_SUPPLEMENTARY_INFO() are provided, each of which takes a GSS + status code and removes all but the relevant field. For example, the + value obtained by applying GSS_ROUTINE_ERROR to a status code removes + the calling errors and supplementary info fields, leaving only the + routine errors field. The values delivered by these macros may be + directly compared with a GSS_S_xxx symbol of the appropriate type. + The macro GSS_ERROR() is also provided, which when applied to a GSS + status code returns a non-zero value if the status code indicated a + calling or routine error, and a zero value otherwise. All macros + defined by GSS-API evaluate their argument(s) exactly once. + + A GSS-API implementation may choose to signal calling errors in a + platform-specific manner instead of, or in addition to the routine + value; routine errors and supplementary info should be returned via + major status values only. + + The GSS major status code GSS_S_FAILURE is used to indicate that the + underlying mechanism detected an error for which no specific GSS + status code is defined. The mechanism-specific status code will + provide more details about the error. + + + +Wray Standards Track [Page 14] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +3.9.2. Mechanism-specific status codes + + GSS-API routines return a minor_status parameter, which is used to + indicate specialized errors from the underlying security mechanism. + This parameter may contain a single mechanism-specific error, + indicated by a OM_uint32 value. + + The minor_status parameter will always be set by a GSS-API routine, + even if it returns a calling error or one of the generic API errors + indicated above as fatal, although most other output parameters may + remain unset in such cases. However, output parameters that are + expected to return pointers to storage allocated by a routine must + always be set by the routine, even in the event of an error, although + in such cases the GSS-API routine may elect to set the returned + parameter value to NULL to indicate that no storage was actually + allocated. Any length field associated with such pointers (as in a + gss_buffer_desc structure) should also be set to zero in such cases. + +3.10. Names + + A name is used to identify a person or entity. GSS-API authenticates + the relationship between a name and the entity claiming the name. + + Since different authentication mechanisms may employ different + namespaces for identifying their principals, GSSAPI's naming support + is necessarily complex in multi-mechanism environments (or even in + some single-mechanism environments where the underlying mechanism + supports multiple namespaces). + + Two distinct representations are defined for names: + + An internal form. This is the GSS-API "native" format for names, + represented by the implementation-specific gss_name_t type. It is + opaque to GSS-API callers. A single gss_name_t object may contain + multiple names from different namespaces, but all names should + refer to the same entity. An example of such an internal name + would be the name returned from a call to the gss_inquire_cred + routine, when applied to a credential containing credential + elements for multiple authentication mechanisms employing + different namespaces. This gss_name_t object will contain a + distinct name for the entity for each authentication mechanism. + + For GSS-API implementations supporting multiple namespaces, + objects of type gss_name_t must contain sufficient information to + determine the namespace to which each primitive name belongs. + + + + + + +Wray Standards Track [Page 15] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Mechanism-specific contiguous octet-string forms. A format + capable of containing a single name (from a single namespace). + Contiguous string names are always accompanied by an object + identifier specifying the namespace to which the name belongs, and + their format is dependent on the authentication mechanism that + employs the name. Many, but not all, contiguous string names will + be printable, and may therefore be used by GSS-API applications + for communication with their users. + + Routines (gss_import_name and gss_display_name) are provided to + convert names between contiguous string representations and the + internal gss_name_t type. gss_import_name may support multiple + syntaxes for each supported namespace, allowing users the freedom to + choose a preferred name representation. gss_display_name should use + an implementation-chosen printable syntax for each supported name- + type. + + If an application calls gss_display_name(), passing the internal name + resulting from a call to gss_import_name(), there is no guarantee the + the resulting contiguous string name will be the same as the original + imported string name. Nor do name-space identifiers necessarily + survive unchanged after a journey through the internal name-form. An + example of this might be a mechanism that authenticates X.500 names, + but provides an algorithmic mapping of Internet DNS names into X.500. + That mechanism's implementation of gss_import_name() might, when + presented with a DNS name, generate an internal name that contained + both the original DNS name and the equivalent X.500 name. + Alternatively, it might only store the X.500 name. In the latter + case, gss_display_name() would most likely generate a printable X.500 + name, rather than the original DNS name. + + The process of authentication delivers to the context acceptor an + internal name. Since this name has been authenticated by a single + mechanism, it contains only a single name (even if the internal name + presented by the context initiator to gss_init_sec_context had + multiple components). Such names are termed internal mechanism + names, or "MN"s and the names emitted by gss_accept_sec_context() are + always of this type. Since some applications may require MNs without + wanting to incur the overhead of an authentication operation, a + second function, gss_canonicalize_name(), is provided to convert a + general internal name into an MN. + + Comparison of internal-form names may be accomplished via the + gss_compare_name() routine, which returns true if the two names being + compared refer to the same entity. This removes the need for the + application program to understand the syntaxes of the various + printable names that a given GSS-API implementation may support. + Since GSS-API assumes that all primitive names contained within a + + + +Wray Standards Track [Page 16] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + given internal name refer to the same entity, gss_compare_name() can + return true if the two names have at least one primitive name in + common. If the implementation embodies knowledge of equivalence + relationships between names taken from different namespaces, this + knowledge may also allow successful comparison of internal names + containing no overlapping primitive elements. + + When used in large access control lists, the overhead of invoking + gss_import_name() and gss_compare_name() on each name from the ACL + may be prohibitive. As an alternative way of supporting this case, + GSS-API defines a special form of the contiguous string name which + may be compared directly (e.g. with memcmp()). Contiguous names + suitable for comparison are generated by the gss_export_name() + routine, which requires an MN as input. Exported names may be re- + imported by the gss_import_name() routine, and the resulting internal + name will also be an MN. The gss_OID constant GSS_C_NT_EXPORT_NAME + indentifies the "export name" type, and the value of this constant is + given in Appendix A. Structurally, an exported name object consists + of a header containing an OID identifying the mechanism that + authenticated the name, and a trailer containing the name itself, + where the syntax of the trailer is defined by the individual + mechanism specification. The precise format of an export name is + defined in the language-independent GSS-API specification [GSSAPI]. + + Note that the results obtained by using gss_compare_name() will in + general be different from those obtained by invoking + gss_canonicalize_name() and gss_export_name(), and then comparing the + exported names. The first series of operation determines whether two + (unauthenticated) names identify the same principal; the second + whether a particular mechanism would authenticate them as the same + principal. These two operations will in general give the same + results only for MNs. + + The gss_name_t datatype should be implemented as a pointer type. To + allow the compiler to aid the application programmer by performing + type-checking, the use of (void *) is discouraged. A pointer to an + implementation-defined type is the preferred choice. + + Storage is allocated by routines that return gss_name_t values. A + procedure, gss_release_name, is provided to free storage associated + with an internal-form name. + + + + + + + + + + +Wray Standards Track [Page 17] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +3.11. Channel Bindings + + GSS-API supports the use of user-specified tags to identify a given + context to the peer application. These tags are intended to be used + to identify the particular communications channel that carries the + context. Channel bindings are communicated to the GSS-API using the + following structure: + + typedef struct gss_channel_bindings_struct { + OM_uint32 initiator_addrtype; + gss_buffer_desc initiator_address; + OM_uint32 acceptor_addrtype; + gss_buffer_desc acceptor_address; + gss_buffer_desc application_data; + } *gss_channel_bindings_t; + + The initiator_addrtype and acceptor_addrtype fields denote the type + of addresses contained in the initiator_address and acceptor_address + buffers. The address type should be one of the following: + + GSS_C_AF_UNSPEC Unspecified address type + GSS_C_AF_LOCAL Host-local address type + GSS_C_AF_INET Internet address type (e.g. IP) + GSS_C_AF_IMPLINK ARPAnet IMP address type + GSS_C_AF_PUP pup protocols (eg BSP) address type + GSS_C_AF_CHAOS MIT CHAOS protocol address type + GSS_C_AF_NS XEROX NS address type + GSS_C_AF_NBS nbs address type + GSS_C_AF_ECMA ECMA address type + GSS_C_AF_DATAKIT datakit protocols address type + GSS_C_AF_CCITT CCITT protocols + GSS_C_AF_SNA IBM SNA address type + GSS_C_AF_DECnet DECnet address type + GSS_C_AF_DLI Direct data link interface address type + GSS_C_AF_LAT LAT address type + GSS_C_AF_HYLINK NSC Hyperchannel address type + GSS_C_AF_APPLETALK AppleTalk address type + GSS_C_AF_BSC BISYNC 2780/3780 address type + GSS_C_AF_DSS Distributed system services address type + GSS_C_AF_OSI OSI TP4 address type + GSS_C_AF_X25 X.25 + GSS_C_AF_NULLADDR No address specified + + Note that these symbols name address families rather than specific + addressing formats. For address families that contain several + alternative address forms, the initiator_address and acceptor_address + fields must contain sufficient information to determine which address + + + + +Wray Standards Track [Page 18] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + form is used. When not otherwise specified, addresses should be + specified in network byte-order (that is, native byte-ordering for + the address family). + + Conceptually, the GSS-API concatenates the initiator_addrtype, + initiator_address, acceptor_addrtype, acceptor_address and + application_data to form an octet string. The mechanism calculates a + MIC over this octet string, and binds the MIC to the context + establishment token emitted by gss_init_sec_context. The same + bindings are presented by the context acceptor to + gss_accept_sec_context, and a MIC is calculated in the same way. The + calculated MIC is compared with that found in the token, and if the + MICs differ, gss_accept_sec_context will return a GSS_S_BAD_BINDINGS + error, and the context will not be established. Some mechanisms may + include the actual channel binding data in the token (rather than + just a MIC); applications should therefore not use confidential data + as channel-binding components. + + Individual mechanisms may impose additional constraints on addresses + and address types that may appear in channel bindings. For example, + a mechanism may verify that the initiator_address field of the + channel bindings presented to gss_init_sec_context contains the + correct network address of the host system. Portable applications + should therefore ensure that they either provide correct information + for the address fields, or omit addressing information, specifying + GSS_C_AF_NULLADDR as the address-types. + +3.12. Optional parameters + + Various parameters are described as optional. This means that they + follow a convention whereby a default value may be requested. The + following conventions are used for omitted parameters. These + conventions apply only to those parameters that are explicitly + documented as optional. + +3.12.1. gss_buffer_t types + + Specify GSS_C_NO_BUFFER as a value. For an input parameter this + signifies that default behavior is requested, while for an output + parameter it indicates that the information that would be returned + via the parameter is not required by the application. + +3.12.2. Integer types (input) + + Individual parameter documentation lists values to be used to + indicate default actions. + + + + + +Wray Standards Track [Page 19] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +3.12.3. Integer types (output) + + Specify NULL as the value for the pointer. + +3.12.4. Pointer types + + Specify NULL as the value. + +3.12.5. Object IDs + + Specify GSS_C_NO_OID as the value. + +3.12.6. Object ID Sets + + Specify GSS_C_NO_OID_SET as the value. + +3.12.7. Channel Bindings + + Specify GSS_C_NO_CHANNEL_BINDINGS to indicate that channel bindings + are not to be used. + +4. Additional Controls + + This section discusses the optional services that a context initiator + may request of the GSS-API at context establishment. Each of these + services is requested by setting a flag in the req_flags input + parameter to gss_init_sec_context. + + The optional services currently defined are: + + Delegation - The (usually temporary) transfer of rights from + initiator to acceptor, enabling the acceptor to authenticate + itself as an agent of the initiator. + + Mutual Authentication - In addition to the initiator authenticating + its identity to the context acceptor, the context acceptor should + also authenticate itself to the initiator. + + Replay detection - In addition to providing message integrity + services, gss_get_mic and gss_wrap should include message + numbering information to enable gss_verify_mic and gss_unwrap to + detect if a message has been duplicated. + + Out-of-sequence detection - In addition to providing message + integrity services, gss_get_mic and gss_wrap should include + message sequencing information to enable gss_verify_mic and + gss_unwrap to detect if a message has been received out of + sequence. + + + +Wray Standards Track [Page 20] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Anonymous authentication - The establishment of the security context + should not reveal the initiator's identity to the context + acceptor. + + Any currently undefined bits within such flag arguments should be + ignored by GSS-API implementations when presented by an application, + and should be set to zero when returned to the application by the + GSS-API implementation. + + Some mechanisms may not support all optional services, and some + mechanisms may only support some services in conjunction with others. + Both gss_init_sec_context and gss_accept_sec_context inform the + applications which services will be available from the context when + the establishment phase is complete, via the ret_flags output + parameter. In general, if the security mechanism is capable of + providing a requested service, it should do so, even if additional + services must be enabled in order to provide the requested service. + If the mechanism is incapable of providing a requested service, it + should proceed without the service, leaving the application to abort + the context establishment process if it considers the requested + service to be mandatory. + + Some mechanisms may specify that support for some services is + optional, and that implementors of the mechanism need not provide it. + This is most commonly true of the confidentiality service, often + because of legal restrictions on the use of data-encryption, but may + apply to any of the services. Such mechanisms are required to send + at least one token from acceptor to initiator during context + establishment when the initiator indicates a desire to use such a + service, so that the initiating GSS-API can correctly indicate + whether the service is supported by the acceptor's GSS-API. + +4.1. Delegation + + The GSS-API allows delegation to be controlled by the initiating + application via a boolean parameter to gss_init_sec_context(), the + routine that establishes a security context. Some mechanisms do not + support delegation, and for such mechanisms attempts by an + application to enable delegation are ignored. + + The acceptor of a security context for which the initiator enabled + delegation will receive (via the delegated_cred_handle parameter of + gss_accept_sec_context) a credential handle that contains the + delegated identity, and this credential handle may be used to + initiate subsequent GSS-API security contexts as an agent or delegate + of the initiator. If the original initiator's identity is "A" and + the delegate's identity is "B", then, depending on the underlying + mechanism, the identity embodied by the delegated credential may be + + + +Wray Standards Track [Page 21] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + either "A" or "B acting for A". + + For many mechanisms that support delegation, a simple boolean does + not provide enough control. Examples of additional aspects of + delegation control that a mechanism might provide to an application + are duration of delegation, network addresses from which delegation + is valid, and constraints on the tasks that may be performed by a + delegate. Such controls are presently outside the scope of the GSS- + API. GSS-API implementations supporting mechanisms offering + additional controls should provide extension routines that allow + these controls to be exercised (perhaps by modifying the initiator's + GSS-API credential prior to its use in establishing a context). + However, the simple delegation control provided by GSS-API should + always be able to over-ride other mechanism-specific delegation + controls - If the application instructs gss_init_sec_context() that + delegation is not desired, then the implementation must not permit + delegation to occur. This is an exception to the general rule that a + mechanism may enable services even if they are not requested - + delegation may only be provided at the explicit request of the + application. + +4.2. Mutual authentication + + Usually, a context acceptor will require that a context initiator + authenticate itself so that the acceptor may make an access-control + decision prior to performing a service for the initiator. In some + cases, the initiator may also request that the acceptor authenticate + itself. GSS-API allows the initiating application to request this + mutual authentication service by setting a flag when calling + gss_init_sec_context. + + The initiating application is informed as to whether or not the + context acceptor has authenticated itself. Note that some mechanisms + may not support mutual authentication, and other mechanisms may + always perform mutual authentication, whether or not the initiating + application requests it. In particular, mutual authentication my be + required by some mechanisms in order to support replay or out-of- + sequence message detection, and for such mechanisms a request for + either of these services will automatically enable mutual + authentication. + + + + + + + + + + + +Wray Standards Track [Page 22] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +4.3. Replay and out-of-sequence detection + + The GSS-API may provide detection of mis-ordered message once a + security context has been established. Protection may be applied to + messages by either application, by calling either gss_get_mic or + gss_wrap, and verified by the peer application by calling + gss_verify_mic or gss_unwrap. + + gss_get_mic calculates a cryptographic MIC over an application + message, and returns that MIC in a token. The application should + pass both the token and the message to the peer application, which + presents them to gss_verify_mic. + + gss_wrap calculates a cryptographic MIC of an application message, + and places both the MIC and the message inside a single token. The + Application should pass the token to the peer application, which + presents it to gss_unwrap to extract the message and verify the MIC. + + Either pair of routines may be capable of detecting out-of-sequence + message delivery, or duplication of messages. Details of such mis- + ordered messages are indicated through supplementary status bits in + the major status code returned by gss_verify_mic or gss_unwrap. The + relevant supplementary bits are: + + GSS_S_DUPLICATE_TOKEN - The token is a duplicate of one that has + already been received and processed. Only + contexts that claim to provide replay detection + may set this bit. + GSS_S_OLD_TOKEN - The token is too old to determine whether or + not it is a duplicate. Contexts supporting + out-of-sequence detection but not replay + detection should always set this bit if + GSS_S_UNSEQ_TOKEN is set; contexts that support + replay detection should only set this bit if the + token is so old that it cannot be checked for + duplication. + GSS_S_UNSEQ_TOKEN - A later token has already been processed. + GSS_S_GAP_TOKEN - An earlier token has not yet been received. + + A mechanism need not maintain a list of all tokens that have been + processed in order to support these status codes. A typical + mechanism might retain information about only the most recent "N" + tokens processed, allowing it to distinguish duplicates and missing + tokens within the most recent "N" messages; the receipt of a token + older than the most recent "N" would result in a GSS_S_OLD_TOKEN + status. + + + + + +Wray Standards Track [Page 23] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +4.4. Anonymous Authentication + + In certain situations, an application may wish to initiate the + authentication process to authenticate a peer, without revealing its + own identity. As an example, consider an application providing + access to a database containing medical information, and offering + unrestricted access to the service. A client of such a service might + wish to authenticate the service (in order to establish trust in any + information retrieved from it), but might not wish the service to be + able to obtain the client's identity (perhaps due to privacy concerns + about the specific inquiries, or perhaps simply to avoid being placed + on mailing-lists). + + In normal use of the GSS-API, the initiator's identity is made + available to the acceptor as a result of the context establishment + process. However, context initiators may request that their identity + not be revealed to the context acceptor. Many mechanisms do not + support anonymous authentication, and for such mechanisms the request + will not be honored. An authentication token will be still be + generated, but the application is always informed if a requested + service is unavailable, and has the option to abort context + establishment if anonymity is valued above the other security + services that would require a context to be established. + + In addition to informing the application that a context is + established anonymously (via the ret_flags outputs from + gss_init_sec_context and gss_accept_sec_context), the optional + src_name output from gss_accept_sec_context and gss_inquire_context + will, for such contexts, return a reserved internal-form name, + defined by the implementation. + + When presented to gss_display_name, this reserved internal-form name + will result in a printable name that is syntactically distinguishable + from any valid principal name supported by the implementation, + associated with a name-type object identifier with the value + GSS_C_NT_ANONYMOUS, whose value us given in Appendix A. The + printable form of an anonymous name should be chosen such that it + implies anonymity, since this name may appear in, for example, audit + logs. For example, the string "<anonymous>" might be a good choice, + if no valid printable names supported by the implementation can begin + with "<" and end with ">". + +4.5. Confidentiality + + If a context supports the confidentiality service, gss_wrap may be + used to encrypt application messages. Messages are selectively + encrypted, under the control of the conf_req_flag input parameter to + gss_wrap. + + + +Wray Standards Track [Page 24] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +4.6. Inter-process context transfer + + GSS-API V2 provides routines (gss_export_sec_context and + gss_import_sec_context) which allow a security context to be + transferred between processes on a single machine. The most common + use for such a feature is a client-server design where the server is + implemented as a single process that accepts incoming security + contexts, which then launches child processes to deal with the data + on these contexts. In such a design, the child processes must have + access to the security context data structure created within the + parent by its call to gss_accept_sec_context so that they can use + per-message protection services and delete the security context when + the communication session ends. + + Since the security context data structure is expected to contain + sequencing information, it is impractical in general to share a + context between processes. Thus GSS-API provides a call + (gss_export_sec_context) that the process which currently owns the + context can call to declare that it has no intention to use the + context subsequently, and to create an inter-process token containing + information needed by the adopting process to successfully import the + context. After successful completion of gss_export_sec_context, the + original security context is made inaccessible to the calling process + by GSS-API, and any context handles referring to this context are no + longer valid. The originating process transfers the inter-process + token to the adopting process, which passes it to + gss_import_sec_context, and a fresh gss_ctx_id_t is created such that + it is functionally identical to the original context. + + The inter-process token may contain sensitive data from the original + security context (including cryptographic keys). Applications using + inter-process tokens to transfer security contexts must take + appropriate steps to protect these tokens in transit. + + Implementations are not required to support the inter-process + transfer of security contexts. The ability to transfer a security + context is indicated when the context is created, by + gss_init_sec_context or gss_accept_sec_context setting the + GSS_C_TRANS_FLAG bit in their ret_flags parameter. + +4.7. The use of incomplete contexts + + Some mechanisms may allow the per-message services to be used before + the context establishment process is complete. For example, a + mechanism may include sufficient information in its initial context- + level token for the context acceptor to immediately decode messages + protected with gss_wrap or gss_get_mic. For such a mechanism, the + initiating application need not wait until subsequent context-level + + + +Wray Standards Track [Page 25] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + tokens have been sent and received before invoking the per-message + protection services. + + The ability of a context to provide per-message services in advance + of complete context establishment is indicated by the setting of the + GSS_C_PROT_READY_FLAG bit in the ret_flags parameter from + gss_init_sec_context and gss_accept_sec_context. Applications wishing + to use per-message protection services on partially-established + contexts should check this flag before attempting to invoke gss_wrap + or gss_get_mic. + +5. GSS-API Routine Descriptions + + In addition to the explicit major status codes documented here, the + code GSS_S_FAILURE may be returned by any routine, indicating an + implementation-specific or mechanism-specific error condition, + further details of which are reported via the minor_status parameter. + +5.1. gss_accept_sec_context + + OM_uint32 gss_accept_sec_context ( + OM_uint32 *minor_status, + gss_ctx_id_t *context_handle, + const gss_cred_id_t acceptor_cred_handle, + const gss_buffer_t input_token_buffer, + const gss_channel_bindings_t input_chan_bindings, + const gss_name_t *src_name, + gss_OID *mech_type, + gss_buffer_t output_token, + OM_uint32 *ret_flags, + OM_uint32 *time_rec, + gss_cred_id_t *delegated_cred_handle) + + Purpose: + + Allows a remotely initiated security context between the application + and a remote peer to be established. The routine may return a + output_token which should be transferred to the peer application, + where the peer application will present it to gss_init_sec_context. + If no token need be sent, gss_accept_sec_context will indicate this + by setting the length field of the output_token argument to zero. To + complete the context establishment, one or more reply tokens may be + required from the peer application; if so, gss_accept_sec_context + will return a status flag of GSS_S_CONTINUE_NEEDED, in which case it + should be called again when the reply token is received from the peer + application, passing the token to gss_accept_sec_context via the + input_token parameters. + + + + +Wray Standards Track [Page 26] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Portable applications should be constructed to use the token length + and return status to determine whether a token needs to be sent or + waited for. Thus a typical portable caller should always invoke + gss_accept_sec_context within a loop: + + gss_ctx_id_t context_hdl = GSS_C_NO_CONTEXT; + + do { + receive_token_from_peer(input_token); + maj_stat = gss_accept_sec_context(&min_stat, + &context_hdl, + cred_hdl, + input_token, + input_bindings, + &client_name, + &mech_type, + output_token, + &ret_flags, + &time_rec, + &deleg_cred); + if (GSS_ERROR(maj_stat)) { + report_error(maj_stat, min_stat); + }; + if (output_token->length != 0) { + send_token_to_peer(output_token); + + gss_release_buffer(&min_stat, output_token); + }; + if (GSS_ERROR(maj_stat)) { + if (context_hdl != GSS_C_NO_CONTEXT) + gss_delete_sec_context(&min_stat, + &context_hdl, + GSS_C_NO_BUFFER); + break; + }; + } while (maj_stat & GSS_S_CONTINUE_NEEDED); + + Whenever the routine returns a major status that includes the value + GSS_S_CONTINUE_NEEDED, the context is not fully established and the + following restrictions apply to the output parameters: + + The value returned via the time_rec parameter is undefined Unless the + accompanying ret_flags parameter contains the bit + GSS_C_PROT_READY_FLAG, indicating that per-message services may be + applied in advance of a successful completion status, the value + returned via the mech_type parameter may be undefined until the + routine returns a major status value of GSS_S_COMPLETE. + + + + +Wray Standards Track [Page 27] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + The values of the GSS_C_DELEG_FLAG, + GSS_C_MUTUAL_FLAG,GSS_C_REPLAY_FLAG, GSS_C_SEQUENCE_FLAG, + GSS_C_CONF_FLAG,GSS_C_INTEG_FLAG and GSS_C_ANON_FLAG bits returned + via the ret_flags parameter should contain the values that the + implementation expects would be valid if context establishment were + to succeed. + + The values of the GSS_C_PROT_READY_FLAG and GSS_C_TRANS_FLAG bits + within ret_flags should indicate the actual state at the time + gss_accept_sec_context returns, whether or not the context is fully + established. + + Although this requires that GSS-API implementations set the + GSS_C_PROT_READY_FLAG in the final ret_flags returned to a caller + (i.e. when accompanied by a GSS_S_COMPLETE status code), applications + should not rely on this behavior as the flag was not defined in + Version 1 of the GSS-API. Instead, applications should be prepared to + use per-message services after a successful context establishment, + according to the GSS_C_INTEG_FLAG and GSS_C_CONF_FLAG values. + + All other bits within the ret_flags argument should be set to zero. + While the routine returns GSS_S_CONTINUE_NEEDED, the values returned + via the ret_flags argument indicate the services that the + implementation expects to be available from the established context. + + If the initial call of gss_accept_sec_context() fails, the + implementation should not create a context object, and should leave + the value of the context_handle parameter set to GSS_C_NO_CONTEXT to + indicate this. In the event of a failure on a subsequent call, the + implementation is permitted to delete the "half-built" security + context (in which case it should set the context_handle parameter to + GSS_C_NO_CONTEXT), but the preferred behavior is to leave the + security context (and the context_handle parameter) untouched for the + application to delete (using gss_delete_sec_context). + + During context establishment, the informational status bits + GSS_S_OLD_TOKEN and GSS_S_DUPLICATE_TOKEN indicate fatal errors, and + GSS-API mechanisms should always return them in association with a + routine error of GSS_S_FAILURE. This requirement for pairing did not + exist in version 1 of the GSS-API specification, so applications that + wish to run over version 1 implementations must special-case these + codes. + + + + + + + + + +Wray Standards Track [Page 28] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Parameters: + + context_handle gss_ctx_id_t, read/modify context handle for new + context. Supply GSS_C_NO_CONTEXT for first + call; use value returned in subsequent calls. + Once gss_accept_sec_context() has returned a + value via this parameter, resources have been + assigned to the corresponding context, and must + be freed by the application after use with a + call to gss_delete_sec_context(). + + + acceptor_cred_handle gss_cred_id_t, read Credential handle claimed + by context acceptor. Specify + GSS_C_NO_CREDENTIAL to accept the context as a + default principal. If GSS_C_NO_CREDENTIAL is + specified, but no default acceptor principal is + defined, GSS_S_NO_CRED will be returned. + + input_token_buffer buffer, opaque, read token obtained from remote + application. + + input_chan_bindings channel bindings, read, optional Application- + specified bindings. Allows application to + securely bind channel identification information + to the security context. If channel bindings + are not used, specify GSS_C_NO_CHANNEL_BINDINGS. + + src_name gss_name_t, modify, optional Authenticated name + of context initiator. After use, this name + should be deallocated by passing it to + gss_release_name(). If not required, specify + NULL. + + mech_type Object ID, modify, optional Security mechanism + used. The returned OID value will be a pointer + into static storage, and should be treated as + read-only by the caller (in particular, it does + not need to be freed). If not required, specify + NULL. + + output_token buffer, opaque, modify Token to be passed to + peer application. If the length field of the + returned token buffer is 0, then no token need + be passed to the peer application. If a non- + zero length field is returned, the associated + storage must be freed after use by the + application with a call to gss_release_buffer(). + + + +Wray Standards Track [Page 29] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + ret_flags bit-mask, modify, optional Contains various + independent flags, each of which indicates that + the context supports a specific service option. + If not needed, specify NULL. Symbolic names are + provided for each flag, and the symbolic names + corresponding to the required flags should be + logically-ANDed with the ret_flags value to test + whether a given option is supported by the + context. The flags are: + GSS_C_DELEG_FLAG + True - Delegated credentials are available + via the delegated_cred_handle + parameter + False - No credentials were delegated + GSS_C_MUTUAL_FLAG + True - Remote peer asked for mutual + authentication + False - Remote peer did not ask for mutual + authentication + GSS_C_REPLAY_FLAG + True - replay of protected messages + will be detected + False - replayed messages will not be + detected + GSS_C_SEQUENCE_FLAG + True - out-of-sequence protected + messages will be detected + False - out-of-sequence messages will not + be detected + GSS_C_CONF_FLAG + True - Confidentiality service may be + invoked by calling the gss_wrap + routine + False - No confidentiality service (via + gss_wrap) available. gss_wrap will + provide message encapsulation, + data-origin authentication and + integrity services only. + GSS_C_INTEG_FLAG + True - Integrity service may be invoked by + calling either gss_get_mic or + gss_wrap routines. + False - Per-message integrity service + unavailable. + GSS_C_ANON_FLAG + True - The initiator does not wish to + be authenticated; the src_name + parameter (if requested) contains + + + +Wray Standards Track [Page 30] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + an anonymous internal name. + False - The initiator has been + authenticated normally. + GSS_C_PROT_READY_FLAG + True - Protection services (as specified + by the states of the GSS_C_CONF_FLAG + and GSS_C_INTEG_FLAG) are available + if the accompanying major status + return value is either GSS_S_COMPLETE + or GSS_S_CONTINUE_NEEDED. + False - Protection services (as specified + by the states of the GSS_C_CONF_FLAG + and GSS_C_INTEG_FLAG) are available + only if the accompanying major status + return value is GSS_S_COMPLETE. + GSS_C_TRANS_FLAG + True - The resultant security context may + be transferred to other processes via + a call to gss_export_sec_context(). + False - The security context is not + transferable. + All other bits should be set to zero. + + time_rec Integer, modify, optional + number of seconds for which the context will + remain valid. Specify NULL if not required. + + delegated_cred_handle + gss_cred_id_t, modify, optional credential + handle for credentials received from context + initiator. Only valid if deleg_flag in + ret_flags is true, in which case an explicit + credential handle (i.e. not GSS_C_NO_CREDENTIAL) + will be returned; if deleg_flag is false, + gss_accept_context() will set this parameter to + GSS_C_NO_CREDENTIAL. If a credential handle is + returned, the associated resources must be + released by the application after use with a + call to gss_release_cred(). Specify NULL if not + required. + + minor_status Integer, modify + Mechanism specific status code. + + GSS_S_CONTINUE_NEEDED Indicates that a token from the peer + application is required to complete the + context, and that gss_accept_sec_context must + be called again with that token. + + + +Wray Standards Track [Page 31] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + GSS_S_DEFECTIVE_TOKEN Indicates that consistency checks performed on + the input_token failed. + + GSS_S_DEFECTIVE_CREDENTIAL Indicates that consistency checks + performed on the credential failed. + + GSS_S_NO_CRED The supplied credentials were not valid for context + acceptance, or the credential handle did not + reference any credentials. + + GSS_S_CREDENTIALS_EXPIRED The referenced credentials have expired. + + GSS_S_BAD_BINDINGS The input_token contains different channel + bindings to those specified via the + input_chan_bindings parameter. + + GSS_S_NO_CONTEXT Indicates that the supplied context handle did not + refer to a valid context. + + GSS_S_BAD_SIG The input_token contains an invalid MIC. + + GSS_S_OLD_TOKEN The input_token was too old. This is a fatal error + during context establishment. + + GSS_S_DUPLICATE_TOKEN The input_token is valid, but is a duplicate of + a token already processed. This is a fatal + error during context establishment. + + GSS_S_BAD_MECH The received token specified a mechanism that is + not supported by the implementation or the + provided credential. + +5.2. gss_acquire_cred + + OM_uint32 gss_acquire_cred ( + OM_uint32 *minor_status, + const gss_name_t desired_name, + OM_uint32 time_req, + const gss_OID_set desired_mechs, + gss_cred_usage_t cred_usage, + gss_cred_id_t *output_cred_handle, + gss_OID_set *actual_mechs, + OM_uint32 *time_rec) + + + + + + + + +Wray Standards Track [Page 32] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Purpose: + + Allows an application to acquire a handle for a pre-existing + credential by name. GSS-API implementations must impose a local + access-control policy on callers of this routine to prevent + unauthorized callers from acquiring credentials to which they are not + entitled. This routine is not intended to provide a "login to the + network" function, as such a function would involve the creation of + new credentials rather than merely acquiring a handle to existing + credentials. Such functions, if required, should be defined in + implementation-specific extensions to the API. + + If desired_name is GSS_C_NO_NAME, the call is interpreted as a + request for a credential handle that will invoke default behavior + when passed to gss_init_sec_context() (if cred_usage is + GSS_C_INITIATE or GSS_C_BOTH) or gss_accept_sec_context() (if + cred_usage is GSS_C_ACCEPT or GSS_C_BOTH). + + Mechanisms should honor the desired_mechs parameter, and return a + credential that is suitable to use only with the requested + mechanisms. An exception to this is the case where one underlying + credential element can be shared by multiple mechanisms; in this case + it is permissible for an implementation to indicate all mechanisms + with which the credential element may be used. If desired_mechs is + an empty set, behavior is undefined. + + This routine is expected to be used primarily by context acceptors, + since implementations are likely to provide mechanism-specific ways + of obtaining GSS-API initiator credentials from the system login + process. Some implementations may therefore not support the + acquisition of GSS_C_INITIATE or GSS_C_BOTH credentials via + gss_acquire_cred for any name other than GSS_C_NO_NAME, or a name + produced by applying either gss_inquire_cred to a valid credential, + or gss_inquire_context to an active context. + + If credential acquisition is time-consuming for a mechanism, the + mechanism may choose to delay the actual acquisition until the + credential is required (e.g. by gss_init_sec_context or + gss_accept_sec_context). Such mechanism-specific implementation + decisions should be invisible to the calling application; thus a call + of gss_inquire_cred immediately following the call of + gss_acquire_cred must return valid credential data, and may therefore + incur the overhead of a deferred credential acquisition. + + + + + + + + +Wray Standards Track [Page 33] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Parameters: + + desired_name gss_name_t, read + Name of principal whose credential + should be acquired + + time_req Integer, read, optional + number of seconds that credentials + should remain valid. Specify GSS_C_INDEFINITE + to request that the credentials have the maximum + permitted lifetime. + + desired_mechs Set of Object IDs, read, optional + set of underlying security mechanisms that + may be used. GSS_C_NO_OID_SET may be used + to obtain an implementation-specific default. + + cred_usage gss_cred_usage_t, read + GSS_C_BOTH - Credentials may be used + either to initiate or accept + security contexts. + GSS_C_INITIATE - Credentials will only be + used to initiate security contexts. + GSS_C_ACCEPT - Credentials will only be used to + accept security contexts. + + output_cred_handle gss_cred_id_t, modify + The returned credential handle. Resources + associated with this credential handle must + be released by the application after use + with a call to gss_release_cred(). + + actual_mechs Set of Object IDs, modify, optional + The set of mechanisms for which the + credential is valid. Storage associated + with the returned OID-set must be released by + the application after use with a call to + gss_release_oid_set(). Specify NULL if not + required. + + time_rec Integer, modify, optional + Actual number of seconds for which the + returned credentials will remain valid. If the + implementation does not support expiration of + credentials, the value GSS_C_INDEFINITE will + be returned. Specify NULL if not required + + + + + +Wray Standards Track [Page 34] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + minor_status Integer, modify + Mechanism specific status code. + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_BAD_MECH Unavailable mechanism requested + + GSS_S_BAD_NAMETYPE Type contained within desired_name parameter + is not supported + + GSS_S_BAD_NAME Value supplied for desired_name parameter is ill + formed. + + GSS_S_CREDENTIALS_EXPIRED The credentials could not be acquired + Because they have expired. + + GSS_S_NO_CRED No credentials were found for the specified name. + +5.3. gss_add_cred + + OM_uint32 gss_add_cred ( + OM_uint32 *minor_status, + const gss_cred_id_t input_cred_handle, + const gss_name_t desired_name, + const gss_OID desired_mech, + gss_cred_usage_t cred_usage, + OM_uint32 initiator_time_req, + OM_uint32 acceptor_time_req, + gss_cred_id_t *output_cred_handle, + gss_OID_set *actual_mechs, + OM_uint32 *initiator_time_rec, + OM_uint32 *acceptor_time_rec) + + Purpose: + + Adds a credential-element to a credential. The credential-element is + identified by the name of the principal to which it refers. GSS-API + implementations must impose a local access-control policy on callers + of this routine to prevent unauthorized callers from acquiring + credential-elements to which they are not entitled. This routine is + not intended to provide a "login to the network" function, as such a + function would involve the creation of new mechanism-specific + authentication data, rather than merely acquiring a GSS-API handle to + existing data. Such functions, if required, should be defined in + implementation-specific extensions to the API. + + + + +Wray Standards Track [Page 35] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + If desired_name is GSS_C_NO_NAME, the call is interpreted as a + request to add a credential element that will invoke default behavior + when passed to gss_init_sec_context() (if cred_usage is + GSS_C_INITIATE or GSS_C_BOTH) or gss_accept_sec_context() (if + cred_usage is GSS_C_ACCEPT or GSS_C_BOTH). + + This routine is expected to be used primarily by context acceptors, + since implementations are likely to provide mechanism-specific ways + of obtaining GSS-API initiator credentials from the system login + process. Some implementations may therefore not support the + acquisition of GSS_C_INITIATE or GSS_C_BOTH credentials via + gss_acquire_cred for any name other than GSS_C_NO_NAME, or a name + produced by applying either gss_inquire_cred to a valid credential, + or gss_inquire_context to an active context. + + If credential acquisition is time-consuming for a mechanism, the + mechanism may choose to delay the actual acquisition until the + credential is required (e.g. by gss_init_sec_context or + gss_accept_sec_context). Such mechanism-specific implementation + decisions should be invisible to the calling application; thus a call + of gss_inquire_cred immediately following the call of gss_add_cred + must return valid credential data, and may therefore incur the + overhead of a deferred credential acquisition. + + This routine can be used to either compose a new credential + containing all credential-elements of the original in addition to the + newly-acquire credential-element, or to add the new credential- + element to an existing credential. If NULL is specified for the + output_cred_handle parameter argument, the new credential-element + will be added to the credential identified by input_cred_handle; if a + valid pointer is specified for the output_cred_handle parameter, a + new credential handle will be created. + + If GSS_C_NO_CREDENTIAL is specified as the input_cred_handle, + gss_add_cred will compose a credential (and set the + output_cred_handle parameter accordingly) based on default behavior. + That is, the call will have the same effect as if the application had + first made a call to gss_acquire_cred(), specifying the same usage + and passing GSS_C_NO_NAME as the desired_name parameter to obtain an + explicit credential handle embodying default behavior, passed this + credential handle to gss_add_cred(), and finally called + gss_release_cred() on the first credential handle. + + If GSS_C_NO_CREDENTIAL is specified as the input_cred_handle + parameter, a non-NULL output_cred_handle must be supplied. + + + + + + +Wray Standards Track [Page 36] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Parameters: + + minor_status Integer, modify + Mechanism specific status code. + + input_cred_handle gss_cred_id_t, read, optional + The credential to which a credential-element + will be added. If GSS_C_NO_CREDENTIAL is + specified, the routine will compose the new + credential based on default behavior (see + description above). Note that, while the + credential-handle is not modified by + gss_add_cred(), the underlying credential + will be modified if output_credential_handle + is NULL. + + desired_name gss_name_t, read. + Name of principal whose credential + should be acquired. + + desired_mech Object ID, read + Underlying security mechanism with which the + credential may be used. + + cred_usage gss_cred_usage_t, read + GSS_C_BOTH - Credential may be used + either to initiate or accept + security contexts. + GSS_C_INITIATE - Credential will only be + used to initiate security + contexts. + GSS_C_ACCEPT - Credential will only be used to + accept security contexts. + + initiator_time_req Integer, read, optional + number of seconds that the credential + should remain valid for initiating security + contexts. This argument is ignored if the + composed credentials are of type GSS_C_ACCEPT. + Specify GSS_C_INDEFINITE to request that the + credentials have the maximum permitted + initiator lifetime. + + acceptor_time_req Integer, read, optional + number of seconds that the credential + should remain valid for accepting security + contexts. This argument is ignored if the + composed credentials are of type GSS_C_INITIATE. + + + +Wray Standards Track [Page 37] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Specify GSS_C_INDEFINITE to request that the + credentials have the maximum permitted initiator + lifetime. + + output_cred_handle gss_cred_id_t, modify, optional + The returned credential handle, containing + the new credential-element and all the + credential-elements from input_cred_handle. + If a valid pointer to a gss_cred_id_t is + supplied for this parameter, gss_add_cred + creates a new credential handle containing all + credential-elements from the input_cred_handle + and the newly acquired credential-element; if + NULL is specified for this parameter, the newly + acquired credential-element will be added + to the credential identified by input_cred_handle. + + The resources associated with any credential + handle returned via this parameter must be + released by the application after use with a + call to gss_release_cred(). + + actual_mechs Set of Object IDs, modify, optional + The complete set of mechanisms for which + the new credential is valid. Storage for + the returned OID-set must be freed by the + application after use with a call to + gss_release_oid_set(). Specify NULL if + not required. + + initiator_time_rec Integer, modify, optional + Actual number of seconds for which the + returned credentials will remain valid for + initiating contexts using the specified + mechanism. If the implementation or mechanism + does not support expiration of credentials, the + value GSS_C_INDEFINITE will be returned. Specify + NULL if not required + + acceptor_time_rec Integer, modify, optional + Actual number of seconds for which the + returned credentials will remain valid for + accepting security contexts using the specified + mechanism. If the implementation or mechanism + does not support expiration of credentials, the + value GSS_C_INDEFINITE will be returned. Specify + NULL if not required + + + + +Wray Standards Track [Page 38] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_BAD_MECH Unavailable mechanism requested + + GSS_S_BAD_NAMETYPE Type contained within desired_name parameter + is not supported + + GSS_S_BAD_NAME Value supplied for desired_name parameter is + ill-formed. + + GSS_S_DUPLICATE_ELEMENT The credential already contains an element + for the requested mechanism with overlapping + usage and validity period. + + GSS_S_CREDENTIALS_EXPIRED The required credentials could not be + added because they have expired. + + GSS_S_NO_CRED No credentials were found for the specified name. + +5.4. gss_add_oid_set_member + + OM_uint32 gss_add_oid_set_member ( + OM_uint32 *minor_status, + const gss_OID member_oid, + gss_OID_set *oid_set) + + Purpose: + + Add an Object Identifier to an Object Identifier set. This routine + is intended for use in conjunction with gss_create_empty_oid_set when + constructing a set of mechanism OIDs for input to gss_acquire_cred. + The oid_set parameter must refer to an OID-set that was created by + GSS-API (e.g. a set returned by gss_create_empty_oid_set()). GSS-API + creates a copy of the member_oid and inserts this copy into the set, + expanding the storage allocated to the OID-set's elements array if + necessary. The routine may add the new member OID anywhere within + the elements array, and implementations should verify that the new + member_oid is not already contained within the elements array; if the + member_oid is already present, the oid_set should remain unchanged. + + Parameters: + + minor_status Integer, modify + Mechanism specific status code + + + + + +Wray Standards Track [Page 39] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + member_oid Object ID, read + The object identifier to copied into + the set. + + oid_set Set of Object ID, modify + The set in which the object identifier + should be inserted. + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + +5.5. gss_canonicalize_name + + OM_uint32 gss_canonicalize_name ( + OM_uint32 *minor_status, + const gss_name_t input_name, + const gss_OID mech_type, + gss_name_t *output_name) + + Purpose: + + Generate a canonical mechanism name (MN) from an arbitrary internal + name. The mechanism name is the name that would be returned to a + context acceptor on successful authentication of a context where the + initiator used the input_name in a successful call to + gss_acquire_cred, specifying an OID set containing <mech_type> as its + only member, followed by a call to gss_init_sec_context, specifying + <mech_type> as the authentication mechanism. + + Parameters: + + minor_status Integer, modify + Mechanism specific status code + + input_name gss_name_t, read + The name for which a canonical form is + desired + + mech_type Object ID, read + The authentication mechanism for which the + canonical form of the name is desired. The + desired mechanism must be specified explicitly; + no default is provided. + + + + + + + +Wray Standards Track [Page 40] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + output_name gss_name_t, modify + The resultant canonical name. Storage + associated with this name must be freed by + the application after use with a call to + gss_release_name(). + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion. + + GSS_S_BAD_MECH The identified mechanism is not supported. + + GSS_S_BAD_NAMETYPE The provided internal name contains no elements + that could be processed by the specified + mechanism. + + GSS_S_BAD_NAME The provided internal name was ill-formed. + +5.6. gss_compare_name + + OM_uint32 gss_compare_name ( + OM_uint32 *minor_status, + const gss_name_t name1, + const gss_name_t name2, + int *name_equal) + + Purpose: + + Allows an application to compare two internal-form names to determine + whether they refer to the same entity. + + If either name presented to gss_compare_name denotes an anonymous + principal, the routines should indicate that the two names do not + refer to the same identity. + + Parameters: + + minor_status Integer, modify + Mechanism specific status code. + + name1 gss_name_t, read + internal-form name + + name2 gss_name_t, read + internal-form name + + + + + + +Wray Standards Track [Page 41] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + name_equal boolean, modify + non-zero - names refer to same entity + zero - names refer to different entities + (strictly, the names are not known + to refer to the same identity). + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_BAD_NAMETYPE The two names were of incomparable types. + + GSS_S_BAD_NAME One or both of name1 or name2 was ill-formed. + +5.7. gss_context_time + + OM_uint32 gss_context_time ( + OM_uint32 *minor_status, + const gss_ctx_id_t context_handle, + OM_uint32 *time_rec) + + Purpose: + + Determines the number of seconds for which the specified context will + remain valid. + + Parameters: + + minor_status Integer, modify + Implementation specific status code. + + context_handle gss_ctx_id_t, read + Identifies the context to be interrogated. + + time_rec Integer, modify + Number of seconds that the context will remain + valid. If the context has already expired, + zero will be returned. + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_CONTEXT_EXPIRED The context has already expired + + GSS_S_NO_CONTEXT The context_handle parameter did not identify + a valid context + + + + +Wray Standards Track [Page 42] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +5.8. gss_create_empty_oid_set + + OM_uint32 gss_create_empty_oid_set ( + OM_uint32 *minor_status, + gss_OID_set *oid_set) + + Purpose: + + Create an object-identifier set containing no object identifiers, to + which members may be subsequently added using the + gss_add_oid_set_member() routine. These routines are intended to be + used to construct sets of mechanism object identifiers, for input to + gss_acquire_cred. + + Parameters: + + minor_status Integer, modify + Mechanism specific status code + + oid_set Set of Object IDs, modify + The empty object identifier set. + The routine will allocate the + gss_OID_set_desc object, which the + application must free after use with + a call to gss_release_oid_set(). + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + +5.9. gss_delete_sec_context + + OM_uint32 gss_delete_sec_context ( + OM_uint32 *minor_status, + gss_ctx_id_t *context_handle, + gss_buffer_t output_token) + + Purpose: + + Delete a security context. gss_delete_sec_context will delete the + local data structures associated with the specified security context, + and may generate an output_token, which when passed to the peer + gss_process_context_token will instruct it to do likewise. If no + token is required by the mechanism, the GSS-API should set the length + field of the output_token (if provided) to zero. No further security + services may be obtained using the context specified by + context_handle. + + + + +Wray Standards Track [Page 43] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + In addition to deleting established security contexts, + gss_delete_sec_context must also be able to delete "half-built" + security contexts resulting from an incomplete sequence of + gss_init_sec_context()/gss_accept_sec_context() calls. + + The output_token parameter is retained for compatibility with version + 1 of the GSS-API. It is recommended that both peer applications + invoke gss_delete_sec_context passing the value GSS_C_NO_BUFFER for + the output_token parameter, indicating that no token is required, and + that gss_delete_sec_context should simply delete local context data + structures. If the application does pass a valid buffer to + gss_delete_sec_context, mechanisms are encouraged to return a zero- + length token, indicating that no peer action is necessary, and that + no token should be transferred by the application. + + Parameters: + + minor_status Integer, modify + Mechanism specific status code. + + context_handle gss_ctx_id_t, modify + context handle identifying context to delete. + After deleting the context, the GSS-API will set + this context handle to GSS_C_NO_CONTEXT. + + output_token buffer, opaque, modify, optional + token to be sent to remote application to + instruct it to also delete the context. It + is recommended that applications specify + GSS_C_NO_BUFFER for this parameter, requesting + local deletion only. If a buffer parameter is + provided by the application, the mechanism may + return a token in it; mechanisms that implement + only local deletion should set the length field of + this token to zero to indicate to the application + that no token is to be sent to the peer. + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_NO_CONTEXT No valid context was supplied + + + + + + + + + +Wray Standards Track [Page 44] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +5.10.gss_display_name + + OM_uint32 gss_display_name ( + OM_uint32 *minor_status, + const gss_name_t input_name, + gss_buffer_t output_name_buffer, + gss_OID *output_name_type) + + Purpose: + + Allows an application to obtain a textual representation of an opaque + internal-form name for display purposes. The syntax of a printable + name is defined by the GSS-API implementation. + + If input_name denotes an anonymous principal, the implementation + should return the gss_OID value GSS_C_NT_ANONYMOUS as the + output_name_type, and a textual name that is syntactically distinct + from all valid supported printable names in output_name_buffer. + + If input_name was created by a call to gss_import_name, specifying + GSS_C_NO_OID as the name-type, implementations that employ lazy + conversion between name types may return GSS_C_NO_OID via the + output_name_type parameter. + + Parameters: + + minor_status Integer, modify + Mechanism specific status code. + + input_name gss_name_t, read + name to be displayed + + output_name_buffer buffer, character-string, modify + buffer to receive textual name string. + The application must free storage associated + with this name after use with a call to + gss_release_buffer(). + + output_name_type Object ID, modify, optional + The type of the returned name. The returned + gss_OID will be a pointer into static storage, + and should be treated as read-only by the caller + (in particular, the application should not attempt + to free it). Specify NULL if not required. + + + + + + + +Wray Standards Track [Page 45] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_BAD_NAME input_name was ill-formed + +5.11.gss_display_status + + OM_uint32 gss_display_status ( + OM_uint32 *minor_status, + OM_uint32 status_value, + int status_type, + const gss_OID mech_type, + OM_uint32 *message_context, + gss_buffer_t status_string) + + Purpose: + + Allows an application to obtain a textual representation of a GSS-API + status code, for display to the user or for logging purposes. Since + some status values may indicate multiple conditions, applications may + need to call gss_display_status multiple times, each call generating + a single text string. The message_context parameter is used by + gss_display_status to store state information about which error + messages have already been extracted from a given status_value; + message_context must be initialized to 0 by the application prior to + the first call, and gss_display_status will return a non-zero value + in this parameter if there are further messages to extract. + + The message_context parameter contains all state information required + by gss_display_status in order to extract further messages from the + status_value; even when a non-zero value is returned in this + parameter, the application is not required to call gss_display_status + again unless subsequent messages are desired. The following code + extracts all messages from a given status code and prints them to + stderr: + + OM_uint32 message_context; + OM_uint32 status_code; + OM_uint32 maj_status; + OM_uint32 min_status; + gss_buffer_desc status_string; + + ... + + message_context = 0; + + do { + + + +Wray Standards Track [Page 46] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + maj_status = gss_display_status ( + &min_status, + status_code, + GSS_C_GSS_CODE, + GSS_C_NO_OID, + &message_context, + &status_string) + + fprintf(stderr, + "%.*s\n", + (int)status_string.length, + + (char *)status_string.value); + + gss_release_buffer(&min_status, &status_string); + + } while (message_context != 0); + + + Parameters: + + minor_status Integer, modify + Mechanism specific status code. + + status_value Integer, read + Status value to be converted + + status_type Integer, read + GSS_C_GSS_CODE - status_value is a GSS status + code + + GSS_C_MECH_CODE - status_value is a mechanism + status code + + mech_type Object ID, read, optional + Underlying mechanism (used to interpret a + minor status value) Supply GSS_C_NO_OID to + obtain the system default. + + message_context Integer, read/modify + Should be initialized to zero by the + application prior to the first call. + On return from gss_display_status(), + a non-zero status_value parameter indicates + that additional messages may be extracted + from the status code via subsequent calls + + + + + +Wray Standards Track [Page 47] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + to gss_display_status(), passing the same + status_value, status_type, mech_type, and + message_context parameters. + + status_string buffer, character string, modify + textual interpretation of the status_value. + Storage associated with this parameter must + be freed by the application after use with + a call to gss_release_buffer(). + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_BAD_MECH Indicates that translation in accordance with + an unsupported mechanism type was requested + + GSS_S_BAD_STATUS The status value was not recognized, or the + status type was neither GSS_C_GSS_CODE nor + GSS_C_MECH_CODE. + +5.12. gss_duplicate_name + + OM_uint32 gss_duplicate_name ( + OM_uint32 *minor_status, + const gss_name_t src_name, + gss_name_t *dest_name) + + Purpose: + + Create an exact duplicate of the existing internal name src_name. + The new dest_name will be independent of src_name (i.e. src_name and + dest_name must both be released, and the release of one shall not + affect the validity of the other). + + Parameters: + + minor_status Integer, modify + Mechanism specific status code. + + src_name gss_name_t, read + internal name to be duplicated. + + dest_name gss_name_t, modify + The resultant copy of <src_name>. + Storage associated with this name must + be freed by the application after use + with a call to gss_release_name(). + + + +Wray Standards Track [Page 48] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_BAD_NAME The src_name parameter was ill-formed. + +5.13. gss_export_name + + OM_uint32 gss_export_name ( + OM_uint32 *minor_status, + const gss_name_t input_name, + gss_buffer_t exported_name) + + Purpose: + + To produce a canonical contiguous string representation of a + mechanism name (MN), suitable for direct comparison (e.g. with + memcmp) for use in authorization functions (e.g. matching entries in + an access-control list). The <input_name> parameter must specify a + valid MN (i.e. an internal name generated by gss_accept_sec_context + or by gss_canonicalize_name). + + Parameters: + + minor_status Integer, modify + Mechanism specific status code + + input_name gss_name_t, read + The MN to be exported + + exported_name gss_buffer_t, octet-string, modify + The canonical contiguous string form of + <input_name>. Storage associated with + this string must freed by the application + after use with gss_release_buffer(). + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_NAME_NOT_MN The provided internal name was not a mechanism + name. + + GSS_S_BAD_NAME The provided internal name was ill-formed. + + GSS_S_BAD_NAMETYPE The internal name was of a type not supported + by the GSS-API implementation. + + + + +Wray Standards Track [Page 49] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +5.14. gss_export_sec_context + + OM_uint32 gss_export_sec_context ( + OM_uint32 *minor_status, + gss_ctx_id_t *context_handle, + gss_buffer_t interprocess_token) + + Purpose: + + Provided to support the sharing of work between multiple processes. + This routine will typically be used by the context-acceptor, in an + application where a single process receives incoming connection + requests and accepts security contexts over them, then passes the + established context to one or more other processes for message + exchange. gss_export_sec_context() deactivates the security context + for the calling process and creates an interprocess token which, when + passed to gss_import_sec_context in another process, will re-activate + the context in the second process. Only a single instantiation of a + given context may be active at any one time; a subsequent attempt by + a context exporter to access the exported security context will fail. + + The implementation may constrain the set of processes by which the + interprocess token may be imported, either as a function of local + security policy, or as a result of implementation decisions. For + example, some implementations may constrain contexts to be passed + only between processes that run under the same account, or which are + part of the same process group. + + The interprocess token may contain security-sensitive information + (for example cryptographic keys). While mechanisms are encouraged to + either avoid placing such sensitive information within interprocess + tokens, or to encrypt the token before returning it to the + application, in a typical object-library GSS-API implementation this + may not be possible. Thus the application must take care to protect + the interprocess token, and ensure that any process to which the + token is transferred is trustworthy. + + If creation of the interprocess token is successful, the + implementation shall deallocate all process-wide resources associated + with the security context, and set the context_handle to + GSS_C_NO_CONTEXT. In the event of an error that makes it impossible + to complete the export of the security context, the implementation + must not return an interprocess token, and should strive to leave the + security context referenced by the context_handle parameter + untouched. If this is impossible, it is permissible for the + implementation to delete the security context, providing it also sets + the context_handle parameter to GSS_C_NO_CONTEXT. + + + + +Wray Standards Track [Page 50] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Parameters: + + minor_status Integer, modify + Mechanism specific status code + + context_handle gss_ctx_id_t, modify + context handle identifying the context to + transfer. + + interprocess_token buffer, opaque, modify + token to be transferred to target process. + Storage associated with this token must be + freed by the application after use with a + call to gss_release_buffer(). + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_CONTEXT_EXPIRED The context has expired + + GSS_S_NO_CONTEXT The context was invalid + + GSS_S_UNAVAILABLE The operation is not supported. + +5.15. gss_get_mic + + OM_uint32 gss_get_mic ( + OM_uint32 *minor_status, + const gss_ctx_id_t context_handle, + gss_qop_t qop_req, + const gss_buffer_t message_buffer, + gss_buffer_t msg_token) + + Purpose: + + Generates a cryptographic MIC for the supplied message, and places + the MIC in a token for transfer to the peer application. The qop_req + parameter allows a choice between several cryptographic algorithms, + if supported by the chosen mechanism. + + Since some application-level protocols may wish to use tokens emitted + by gss_wrap() to provide "secure framing", implementations must + support derivation of MICs from zero-length messages. + + + + + + + +Wray Standards Track [Page 51] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Parameters: + + minor_status Integer, modify + Implementation specific status code. + + context_handle gss_ctx_id_t, read + identifies the context on which the message + will be sent + + qop_req gss_qop_t, read, optional + Specifies requested quality of protection. + Callers are encouraged, on portability grounds, + to accept the default quality of protection + offered by the chosen mechanism, which may be + requested by specifying GSS_C_QOP_DEFAULT for + this parameter. If an unsupported protection + strength is requested, gss_get_mic will return a + major_status of GSS_S_BAD_QOP. + + message_buffer buffer, opaque, read + message to be protected + + msg_token buffer, opaque, modify + buffer to receive token. The application must + free storage associated with this buffer after + use with a call to gss_release_buffer(). + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_CONTEXT_EXPIRED The context has already expired + + GSS_S_NO_CONTEXT The context_handle parameter did not identify + a valid context + + GSS_S_BAD_QOP The specified QOP is not supported by the + mechanism. + +5.16. gss_import_name + + OM_uint32 gss_import_name ( + OM_uint32 *minor_status, + const gss_buffer_t input_name_buffer, + const gss_OID input_name_type, + gss_name_t *output_name) + + + + + +Wray Standards Track [Page 52] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Purpose: + + Convert a contiguous string name to internal form. In general, the + internal name returned (via the <output_name> parameter) will not be + an MN; the exception to this is if the <input_name_type> indicates + that the contiguous string provided via the <input_name_buffer> + parameter is of type GSS_C_NT_EXPORT_NAME, in which case the returned + internal name will be an MN for the mechanism that exported the name. + + Parameters: + + minor_status Integer, modify + Mechanism specific status code + + input_name_buffer buffer, octet-string, read + buffer containing contiguous string name to convert + + input_name_type Object ID, read, optional + Object ID specifying type of printable + name. Applications may specify either + GSS_C_NO_OID to use a mechanism-specific + default printable syntax, or an OID recognized + by the GSS-API implementation to name a + specific namespace. + + output_name gss_name_t, modify + returned name in internal form. Storage + associated with this name must be freed + by the application after use with a call + to gss_release_name(). + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_BAD_NAMETYPE The input_name_type was unrecognized + + GSS_S_BAD_NAME The input_name parameter could not be interpreted + as a name of the specified type + + GSS_S_BAD_MECH The input name-type was GSS_C_NT_EXPORT_NAME, + but the mechanism contained within the + input-name is not supported + + + + + + + + +Wray Standards Track [Page 53] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +5.17. gss_import_sec_context + + OM_uint32 gss_import_sec_context ( + OM_uint32 *minor_status, + const gss_buffer_t interprocess_token, + gss_ctx_id_t *context_handle) + + Purpose: + + Allows a process to import a security context established by another + process. A given interprocess token may be imported only once. See + gss_export_sec_context. + + Parameters: + + minor_status Integer, modify + Mechanism specific status code + + interprocess_token buffer, opaque, modify + token received from exporting process + + context_handle gss_ctx_id_t, modify + context handle of newly reactivated context. + Resources associated with this context handle + must be released by the application after use + with a call to gss_delete_sec_context(). + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion. + + GSS_S_NO_CONTEXT The token did not contain a valid context + reference. + + GSS_S_DEFECTIVE_TOKEN The token was invalid. + + GSS_S_UNAVAILABLE The operation is unavailable. + + GSS_S_UNAUTHORIZED Local policy prevents the import of this context + by the current process. + +5.18. gss_indicate_mechs + + OM_uint32 gss_indicate_mechs ( + OM_uint32 *minor_status, + gss_OID_set *mech_set) + + + + + +Wray Standards Track [Page 54] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Purpose: + + Allows an application to determine which underlying security + mechanisms are available. + + Parameters: + + minor_status Integer, modify + Mechanism specific status code. + + mech_set set of Object IDs, modify + set of implementation-supported mechanisms. + The returned gss_OID_set value will be a + dynamically-allocated OID set, that should + be released by the caller after use with a + call to gss_release_oid_set(). + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + +5.19. gss_init_sec_context + + OM_uint32 gss_init_sec_context ( + OM_uint32 *minor_status, + const gss_cred_id_t initiator_cred_handle, + gss_ctx_id_t *context_handle,\ + const gss_name_t target_name, + const gss_OID mech_type, + OM_uint32 req_flags, + OM_uint32 time_req, + const gss_channel_bindings_t input_chan_bindings, + const gss_buffer_t input_token + gss_OID *actual_mech_type, + gss_buffer_t output_token, + OM_uint32 *ret_flags, + OM_uint32 *time_rec ) + + Purpose: + + Initiates the establishment of a security context between the + application and a remote peer. Initially, the input_token parameter + should be specified either as GSS_C_NO_BUFFER, or as a pointer to a + gss_buffer_desc object whose length field contains the value zero. + The routine may return a output_token which should be transferred to + the peer application, where the peer application will present it to + gss_accept_sec_context. If no token need be sent, + gss_init_sec_context will indicate this by setting the length field + + + +Wray Standards Track [Page 55] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + of the output_token argument to zero. To complete the context + establishment, one or more reply tokens may be required from the peer + application; if so, gss_init_sec_context will return a status + containing the supplementary information bit GSS_S_CONTINUE_NEEDED. + In this case, gss_init_sec_context should be called again when the + reply token is received from the peer application, passing the reply + token to gss_init_sec_context via the input_token parameters. + + Portable applications should be constructed to use the token length + and return status to determine whether a token needs to be sent or + waited for. Thus a typical portable caller should always invoke + gss_init_sec_context within a loop: + + int context_established = 0; + gss_ctx_id_t context_hdl = GSS_C_NO_CONTEXT; + ... + input_token->length = 0; + + while (!context_established) { + maj_stat = gss_init_sec_context(&min_stat, + cred_hdl, + &context_hdl, + target_name, + desired_mech, + desired_services, + desired_time, + input_bindings, + input_token, + &actual_mech, + output_token, + &actual_services, + &actual_time); + if (GSS_ERROR(maj_stat)) { + report_error(maj_stat, min_stat); + }; + + if (output_token->length != 0) { + send_token_to_peer(output_token); + gss_release_buffer(&min_stat, output_token) + }; + if (GSS_ERROR(maj_stat)) { + + if (context_hdl != GSS_C_NO_CONTEXT) + gss_delete_sec_context(&min_stat, + &context_hdl, + GSS_C_NO_BUFFER); + break; + }; + + + +Wray Standards Track [Page 56] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + if (maj_stat & GSS_S_CONTINUE_NEEDED) { + receive_token_from_peer(input_token); + } else { + context_established = 1; + }; + }; + + Whenever the routine returns a major status that includes the value + GSS_S_CONTINUE_NEEDED, the context is not fully established and the + following restrictions apply to the output parameters: + + The value returned via the time_rec parameter is undefined Unless + the accompanying ret_flags parameter contains the bit + GSS_C_PROT_READY_FLAG, indicating that per-message services may be + applied in advance of a successful completion status, the value + returned via the actual_mech_type parameter is undefined until the + routine returns a major status value of GSS_S_COMPLETE. + + The values of the GSS_C_DELEG_FLAG, GSS_C_MUTUAL_FLAG, + GSS_C_REPLAY_FLAG, GSS_C_SEQUENCE_FLAG, GSS_C_CONF_FLAG, + GSS_C_INTEG_FLAG and GSS_C_ANON_FLAG bits returned via the + ret_flags parameter should contain the values that the + implementation expects would be valid if context establishment + were to succeed. In particular, if the application has requested + a service such as delegation or anonymous authentication via the + req_flags argument, and such a service is unavailable from the + underlying mechanism, gss_init_sec_context should generate a token + that will not provide the service, and indicate via the ret_flags + argument that the service will not be supported. The application + may choose to abort the context establishment by calling + gss_delete_sec_context (if it cannot continue in the absence of + the service), or it may choose to transmit the token and continue + context establishment (if the service was merely desired but not + mandatory). + + The values of the GSS_C_PROT_READY_FLAG and GSS_C_TRANS_FLAG bits + within ret_flags should indicate the actual state at the time + gss_init_sec_context returns, whether or not the context is fully + established. + + GSS-API implementations that support per-message protection are + encouraged to set the GSS_C_PROT_READY_FLAG in the final ret_flags + returned to a caller (i.e. when accompanied by a GSS_S_COMPLETE + status code). However, applications should not rely on this + behavior as the flag was not defined in Version 1 of the GSS-API. + Instead, applications should determine what per-message services + are available after a successful context establishment according + to the GSS_C_INTEG_FLAG and GSS_C_CONF_FLAG values. + + + +Wray Standards Track [Page 57] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + All other bits within the ret_flags argument should be set to + zero. + + If the initial call of gss_init_sec_context() fails, the + implementation should not create a context object, and should leave + the value of the context_handle parameter set to GSS_C_NO_CONTEXT to + indicate this. In the event of a failure on a subsequent call, the + implementation is permitted to delete the "half-built" security + context (in which case it should set the context_handle parameter to + GSS_C_NO_CONTEXT), but the preferred behavior is to leave the + security context untouched for the application to delete (using + gss_delete_sec_context). + + During context establishment, the informational status bits + GSS_S_OLD_TOKEN and GSS_S_DUPLICATE_TOKEN indicate fatal errors, and + GSS-API mechanisms should always return them in association with a + routine error of GSS_S_FAILURE. This requirement for pairing did not + exist in version 1 of the GSS-API specification, so applications that + wish to run over version 1 implementations must special-case these + codes. + + Parameters: + + minor_status Integer, modify + Mechanism specific status code. + + initiator_cred_handle gss_cred_id_t, read, optional + handle for credentials claimed. Supply + GSS_C_NO_CREDENTIAL to act as a default + initiator principal. If no default + initiator is defined, the function will + return GSS_S_NO_CRED. + + context_handle gss_ctx_id_t, read/modify + context handle for new context. Supply + GSS_C_NO_CONTEXT for first call; use value + returned by first call in continuation calls. + Resources associated with this context-handle + must be released by the application after use + with a call to gss_delete_sec_context(). + + target_name gss_name_t, read + Name of target + + mech_type OID, read, optional + Object ID of desired mechanism. Supply + GSS_C_NO_OID to obtain an implementation + specific default + + + +Wray Standards Track [Page 58] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + req_flags bit-mask, read + Contains various independent flags, each of + which requests that the context support a + specific service option. Symbolic + names are provided for each flag, and the + symbolic names corresponding to the required + flags should be logically-ORed + together to form the bit-mask value. The + flags are: + + GSS_C_DELEG_FLAG + True - Delegate credentials to remote peer + False - Don't delegate + + GSS_C_MUTUAL_FLAG + True - Request that remote peer + authenticate itself + False - Authenticate self to remote peer + only + + GSS_C_REPLAY_FLAG + True - Enable replay detection for + messages protected with gss_wrap + or gss_get_mic + False - Don't attempt to detect + replayed messages + + GSS_C_SEQUENCE_FLAG + True - Enable detection of out-of-sequence + protected messages + False - Don't attempt to detect + out-of-sequence messages + + GSS_C_CONF_FLAG + True - Request that confidentiality service + be made available (via gss_wrap) + False - No per-message confidentiality service + is required. + + GSS_C_INTEG_FLAG + True - Request that integrity service be + made available (via gss_wrap or + gss_get_mic) + False - No per-message integrity service + is required. + + + + + + +Wray Standards Track [Page 59] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + GSS_C_ANON_FLAG + True - Do not reveal the initiator's + identity to the acceptor. + False - Authenticate normally. + + time_req Integer, read, optional + Desired number of seconds for which context + should remain valid. Supply 0 to request a + default validity period. + + input_chan_bindings channel bindings, read, optional + Application-specified bindings. Allows + application to securely bind channel + identification information to the security + context. Specify GSS_C_NO_CHANNEL_BINDINGS + if channel bindings are not used. + + input_token buffer, opaque, read, optional (see text) + Token received from peer application. + Supply GSS_C_NO_BUFFER, or a pointer to + a buffer containing the value GSS_C_EMPTY_BUFFER + on initial call. + + actual_mech_type OID, modify, optional + Actual mechanism used. The OID returned via + this parameter will be a pointer to static + storage that should be treated as read-only; + In particular the application should not attempt + to free it. Specify NULL if not required. + + output_token buffer, opaque, modify + token to be sent to peer application. If + the length field of the returned buffer is + zero, no token need be sent to the peer + application. Storage associated with this + buffer must be freed by the application + after use with a call to gss_release_buffer(). + + ret_flags bit-mask, modify, optional + Contains various independent flags, each of which + indicates that the context supports a specific + service option. Specify NULL if not + required. Symbolic names are provided + for each flag, and the symbolic names + corresponding to the required flags should be + logically-ANDed with the ret_flags value to test + whether a given option is supported by the + context. The flags are: + + + +Wray Standards Track [Page 60] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + GSS_C_DELEG_FLAG + True - Credentials were delegated to + the remote peer + False - No credentials were delegated + + GSS_C_MUTUAL_FLAG + True - The remote peer has authenticated + itself. + False - Remote peer has not authenticated + itself. + + GSS_C_REPLAY_FLAG + True - replay of protected messages + will be detected + False - replayed messages will not be + detected + + GSS_C_SEQUENCE_FLAG + True - out-of-sequence protected + messages will be detected + False - out-of-sequence messages will + not be detected + + GSS_C_CONF_FLAG + True - Confidentiality service may be + invoked by calling gss_wrap routine + False - No confidentiality service (via + gss_wrap) available. gss_wrap will + provide message encapsulation, + data-origin authentication and + integrity services only. + + GSS_C_INTEG_FLAG + True - Integrity service may be invoked by + calling either gss_get_mic or gss_wrap + routines. + False - Per-message integrity service + unavailable. + + GSS_C_ANON_FLAG + True - The initiator's identity has not been + revealed, and will not be revealed if + any emitted token is passed to the + acceptor. + False - The initiator's identity has been or + will be authenticated normally. + + GSS_C_PROT_READY_FLAG + + + +Wray Standards Track [Page 61] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + True - Protection services (as specified + by the states of the GSS_C_CONF_FLAG + and GSS_C_INTEG_FLAG) are available for + use if the accompanying major status + return value is either GSS_S_COMPLETE or + GSS_S_CONTINUE_NEEDED. + False - Protection services (as specified + by the states of the GSS_C_CONF_FLAG + and GSS_C_INTEG_FLAG) are available + only if the accompanying major status + return value is GSS_S_COMPLETE. + + GSS_C_TRANS_FLAG + True - The resultant security context may + be transferred to other processes via + a call to gss_export_sec_context(). + False - The security context is not + transferable. + + All other bits should be set to zero. + + time_rec Integer, modify, optional + number of seconds for which the context + will remain valid. If the implementation does + not support context expiration, the value + GSS_C_INDEFINITE will be returned. Specify + NULL if not required. + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_CONTINUE_NEEDED Indicates that a token from the peer + application is required to complete the + context, and that gss_init_sec_context + must be called again with that token. + + GSS_S_DEFECTIVE_TOKEN Indicates that consistency checks performed + on the input_token failed + + GSS_S_DEFECTIVE_CREDENTIAL Indicates that consistency checks + performed on the credential failed. + + GSS_S_NO_CRED The supplied credentials were not valid for + context initiation, or the credential handle + did not reference any credentials. + + GSS_S_CREDENTIALS_EXPIRED The referenced credentials have expired + + + +Wray Standards Track [Page 62] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + GSS_S_BAD_BINDINGS The input_token contains different channel + bindings to those specified via the + input_chan_bindings parameter + + GSS_S_BAD_SIG The input_token contains an invalid MIC, or a MIC + that could not be verified + + GSS_S_OLD_TOKEN The input_token was too old. This is a fatal + error during context establishment + + GSS_S_DUPLICATE_TOKEN The input_token is valid, but is a duplicate + of a token already processed. This is a + fatal error during context establishment. + + GSS_S_NO_CONTEXT Indicates that the supplied context handle did + not refer to a valid context + + GSS_S_BAD_NAMETYPE The provided target_name parameter contained an + invalid or unsupported type of name + + GSS_S_BAD_NAME The provided target_name parameter was ill-formed. + + GSS_S_BAD_MECH The specified mechanism is not supported by the + provided credential, or is unrecognized by the + implementation. + +5.20. gss_inquire_context + + OM_uint32 gss_inquire_context ( + OM_uint32 *minor_status, + const gss_ctx_id_t context_handle, + gss_name_t *src_name, + gss_name_t *targ_name, + OM_uint32 *lifetime_rec, + gss_OID *mech_type, + OM_uint32 *ctx_flags, + int *locally_initiated, + int *open ) + + Purpose: + + Obtains information about a security context. The caller must + already have obtained a handle that refers to the context, although + the context need not be fully established. + + + + + + + +Wray Standards Track [Page 63] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Parameters: + + minor_status Integer, modify + Mechanism specific status code + + context_handle gss_ctx_id_t, read + A handle that refers to the security context. + + src_name gss_name_t, modify, optional + The name of the context initiator. + If the context was established using anonymous + authentication, and if the application invoking + gss_inquire_context is the context acceptor, + an anonymous name will be returned. Storage + associated with this name must be freed by the + application after use with a call to + gss_release_name(). Specify NULL if not + required. + + targ_name gss_name_t, modify, optional + The name of the context acceptor. + Storage associated with this name must be + freed by the application after use with a call + to gss_release_name(). If the context acceptor + did not authenticate itself, and if the initiator + did not specify a target name in its call to + gss_init_sec_context(), the value GSS_C_NO_NAME + will be returned. Specify NULL if not required. + + lifetime_rec Integer, modify, optional + The number of seconds for which the context + will remain valid. If the context has + expired, this parameter will be set to zero. + If the implementation does not support + context expiration, the value + GSS_C_INDEFINITE will be returned. Specify + NULL if not required. + + mech_type gss_OID, modify, optional + The security mechanism providing the + context. The returned OID will be a + pointer to static storage that should + be treated as read-only by the application; + in particular the application should not + attempt to free it. Specify NULL if not + required. + + + + + +Wray Standards Track [Page 64] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + ctx_flags bit-mask, modify, optional + Contains various independent flags, each of + which indicates that the context supports + (or is expected to support, if ctx_open is + false) a specific service option. If not + needed, specify NULL. Symbolic names are + provided for each flag, and the symbolic names + corresponding to the required flags + should be logically-ANDed with the ret_flags + value to test whether a given option is + supported by the context. The flags are: + + GSS_C_DELEG_FLAG + True - Credentials were delegated from + the initiator to the acceptor. + False - No credentials were delegated + + GSS_C_MUTUAL_FLAG + True - The acceptor was authenticated + to the initiator + False - The acceptor did not authenticate + itself. + + GSS_C_REPLAY_FLAG + True - replay of protected messages + will be detected + False - replayed messages will not be + detected + + GSS_C_SEQUENCE_FLAG + True - out-of-sequence protected + messages will be detected + False - out-of-sequence messages will not + be detected + + GSS_C_CONF_FLAG + True - Confidentiality service may be invoked + by calling gss_wrap routine + False - No confidentiality service (via + gss_wrap) available. gss_wrap will + provide message encapsulation, + data-origin authentication and + integrity services only. + + GSS_C_INTEG_FLAG + True - Integrity service may be invoked by + calling either gss_get_mic or gss_wrap + routines. + + + +Wray Standards Track [Page 65] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + False - Per-message integrity service + unavailable. + + GSS_C_ANON_FLAG + True - The initiator's identity will not + be revealed to the acceptor. + The src_name parameter (if + requested) contains an anonymous + internal name. + False - The initiator has been + authenticated normally. + + GSS_C_PROT_READY_FLAG + True - Protection services (as specified + by the states of the GSS_C_CONF_FLAG + and GSS_C_INTEG_FLAG) are available + for use. + False - Protection services (as specified + by the states of the GSS_C_CONF_FLAG + and GSS_C_INTEG_FLAG) are available + only if the context is fully + established (i.e. if the open parameter + is non-zero). + + GSS_C_TRANS_FLAG + True - The resultant security context may + be transferred to other processes via + a call to gss_export_sec_context(). + False - The security context is not + transferable. + + locally_initiated Boolean, modify + Non-zero if the invoking application is the + context initiator. + Specify NULL if not required. + + open Boolean, modify + Non-zero if the context is fully established; + Zero if a context-establishment token + is expected from the peer application. + Specify NULL if not required. + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_NO_CONTEXT The referenced context could not be accessed. + + + + +Wray Standards Track [Page 66] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +5.21. gss_inquire_cred + + OM_uint32 gss_inquire_cred ( + OM_uint32 *minor_status, + const gss_cred_id_t cred_handle, + gss_name_t *name, + OM_uint32 *lifetime, + gss_cred_usage_t *cred_usage, + gss_OID_set *mechanisms ) + + Purpose: + + Obtains information about a credential. + + Parameters: + + minor_status Integer, modify + Mechanism specific status code + + cred_handle gss_cred_id_t, read + A handle that refers to the target credential. + Specify GSS_C_NO_CREDENTIAL to inquire about + the default initiator principal. + + name gss_name_t, modify, optional + The name whose identity the credential asserts. + Storage associated with this name should be freed + by the application after use with a call to + gss_release_name(). Specify NULL if not required. + + lifetime Integer, modify, optional + The number of seconds for which the credential + will remain valid. If the credential has + expired, this parameter will be set to zero. + If the implementation does not support + credential expiration, the value + GSS_C_INDEFINITE will be returned. Specify + NULL if not required. + + cred_usage gss_cred_usage_t, modify, optional + How the credential may be used. One of the + following: + GSS_C_INITIATE + GSS_C_ACCEPT + GSS_C_BOTH + Specify NULL if not required. + + + + + +Wray Standards Track [Page 67] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + mechanisms gss_OID_set, modify, optional + Set of mechanisms supported by the credential. + Storage associated with this OID set must be + freed by the application after use with a call + to gss_release_oid_set(). Specify NULL if not + required. + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_NO_CRED The referenced credentials could not be accessed. + + GSS_S_DEFECTIVE_CREDENTIAL The referenced credentials were invalid. + + GSS_S_CREDENTIALS_EXPIRED The referenced credentials have expired. + If the lifetime parameter was not passed as NULL, + it will be set to 0. + +5.22. gss_inquire_cred_by_mech + + OM_uint32 gss_inquire_cred_by_mech ( + OM_uint32 *minor_status, + const gss_cred_id_t cred_handle, + const gss_OID mech_type, + gss_name_t *name, + OM_uint32 *initiator_lifetime, + OM_uint32 *acceptor_lifetime, + gss_cred_usage_t *cred_usage ) + + Purpose: + + Obtains per-mechanism information about a credential. + + Parameters: + + minor_status Integer, modify + Mechanism specific status code + + cred_handle gss_cred_id_t, read + A handle that refers to the target credential. + Specify GSS_C_NO_CREDENTIAL to inquire about + the default initiator principal. + + mech_type gss_OID, read + The mechanism for which information should be + returned. + + + + +Wray Standards Track [Page 68] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + name gss_name_t, modify, optional + The name whose identity the credential asserts. + Storage associated with this name must be + freed by the application after use with a call + to gss_release_name(). Specify NULL if not + required. + + initiator_lifetime Integer, modify, optional + The number of seconds for which the credential + will remain capable of initiating security contexts + under the specified mechanism. If the credential + can no longer be used to initiate contexts, or if + the credential usage for this mechanism is + GSS_C_ACCEPT, this parameter will be set to zero. + If the implementation does not support expiration + of initiator credentials, the value + GSS_C_INDEFINITE will be returned. Specify NULL + if not required. + + acceptor_lifetime Integer, modify, optional + The number of seconds for which the credential + will remain capable of accepting security contexts + under the specified mechanism. If the credential + can no longer be used to accept contexts, or if + the credential usage for this mechanism is + GSS_C_INITIATE, this parameter will be set to zero. + + If the implementation does not support expiration + of acceptor credentials, the value GSS_C_INDEFINITE + will be returned. Specify NULL if not required. + + cred_usage gss_cred_usage_t, modify, optional + How the credential may be used with the specified + mechanism. One of the following: + GSS_C_INITIATE + GSS_C_ACCEPT + GSS_C_BOTH + Specify NULL if not required. + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_NO_CRED The referenced credentials could not be accessed. + + GSS_S_DEFECTIVE_CREDENTIAL The referenced credentials were invalid. + + + + + +Wray Standards Track [Page 69] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + GSS_S_CREDENTIALS_EXPIRED The referenced credentials have expired. + If the lifetime parameter was not passed as NULL, + it will be set to 0. + +5.23. gss_inquire_mechs_for_name + + OM_uint32 gss_inquire_mechs_for_name ( + OM_uint32 *minor_status, + const gss_name_t input_name, + gss_OID_set *mech_types ) + + Purpose: + + Returns the set of mechanisms supported by the GSS-API implementation + that may be able to process the specified name. + + Each mechanism returned will recognize at least one element within + the name. It is permissible for this routine to be implemented + within a mechanism-independent GSS-API layer, using the type + information contained within the presented name, and based on + registration information provided by individual mechanism + implementations. This means that the returned mech_types set may + indicate that a particular mechanism will understand the name when in + fact it would refuse to accept the name as input to + gss_canonicalize_name, gss_init_sec_context, gss_acquire_cred or + gss_add_cred (due to some property of the specific name, as opposed + to the name type). Thus this routine should be used only as a pre- + filter for a call to a subsequent mechanism-specific routine. + + Parameters: + + minor_status Integer, modify + Implementation specific status code. + + input_name gss_name_t, read + The name to which the inquiry relates. + + mech_types gss_OID_set, modify + Set of mechanisms that may support the + specified name. The returned OID set + must be freed by the caller after use + with a call to gss_release_oid_set(). + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_BAD_NAME The input_name parameter was ill-formed. + + + +Wray Standards Track [Page 70] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + GSS_S_BAD_NAMETYPE The input_name parameter contained an invalid or + unsupported type of name + +5.24. gss_inquire_names_for_mech + + OM_uint32 gss_inquire_names_for_mech ( + OM_uint32 *minor_status, + const gss_OID mechanism, + gss_OID_set *name_types) + + Purpose: + + Returns the set of nametypes supported by the specified mechanism. + + Parameters: + + minor_status Integer, modify + Implementation specific status code. + + mechanism gss_OID, read + The mechanism to be interrogated. + + name_types gss_OID_set, modify + Set of name-types supported by the specified + mechanism. The returned OID set must be + freed by the application after use with a + call to gss_release_oid_set(). + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + +5.25. gss_process_context_token + + OM_uint32 gss_process_context_token ( + OM_uint32 *minor_status, + const gss_ctx_id_t context_handle, + const gss_buffer_t token_buffer) + + Purpose: + + Provides a way to pass an asynchronous token to the security service. + Most context-level tokens are emitted and processed synchronously by + gss_init_sec_context and gss_accept_sec_context, and the application + is informed as to whether further tokens are expected by the + GSS_C_CONTINUE_NEEDED major status bit. Occasionally, a mechanism + may need to emit a context-level token at a point when the peer + entity is not expecting a token. For example, the initiator's final + + + +Wray Standards Track [Page 71] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + call to gss_init_sec_context may emit a token and return a status of + GSS_S_COMPLETE, but the acceptor's call to gss_accept_sec_context may + fail. The acceptor's mechanism may wish to send a token containing + an error indication to the initiator, but the initiator is not + expecting a token at this point, believing that the context is fully + established. Gss_process_context_token provides a way to pass such a + token to the mechanism at any time. + + Parameters: + + minor_status Integer, modify + Implementation specific status code. + + context_handle gss_ctx_id_t, read + context handle of context on which token is to + be processed + + token_buffer buffer, opaque, read + token to process + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_DEFECTIVE_TOKEN Indicates that consistency checks performed + on the token failed + + GSS_S_NO_CONTEXT The context_handle did not refer to a valid context + +5.26. gss_release_buffer + + OM_uint32 gss_release_buffer ( + OM_uint32 *minor_status, + gss_buffer_t buffer) + + Purpose: + + Free storage associated with a buffer. The storage must have been + allocated by a GSS-API routine. In addition to freeing the + associated storage, the routine will zero the length field in the + descriptor to which the buffer parameter refers, and implementations + are encouraged to additionally set the pointer field in the + descriptor to NULL. Any buffer object returned by a GSS-API routine + may be passed to gss_release_buffer (even if there is no storage + associated with the buffer). + + + + + + +Wray Standards Track [Page 72] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Parameters: + + minor_status Integer, modify + Mechanism specific status code + + buffer buffer, modify + The storage associated with the buffer will be + deleted. The gss_buffer_desc object will not + be freed, but its length field will be zeroed. + + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + +5.27. gss_release_cred + + OM_uint32 gss_release_cred ( + OM_uint32 *minor_status, + gss_cred_id_t *cred_handle) + + Purpose: + + Informs GSS-API that the specified credential handle is no longer + required by the application, and frees associated resources. + Implementations are encouraged to set the cred_handle to + GSS_C_NO_CREDENTIAL on successful completion of this call. + + Parameters: + + cred_handle gss_cred_id_t, modify, optional + Opaque handle identifying credential + to be released. If GSS_C_NO_CREDENTIAL + is supplied, the routine will complete + successfully, but will do nothing. + + minor_status Integer, modify + Mechanism specific status code. + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_NO_CRED Credentials could not be accessed. + + + + + + + +Wray Standards Track [Page 73] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +5.28. gss_release_name + + OM_uint32 gss_release_name ( + OM_uint32 *minor_status, + gss_name_t *name) + + Purpose: + + Free GSSAPI-allocated storage associated with an internal-form name. + Implementations are encouraged to set the name to GSS_C_NO_NAME on + successful completion of this call. + + Parameters: + + minor_status Integer, modify + Mechanism specific status code + + name gss_name_t, modify + The name to be deleted + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_BAD_NAME The name parameter did not contain a valid name + +5.29. gss_release_oid_set + + OM_uint32 gss_release_oid_set ( + OM_uint32 *minor_status, + gss_OID_set *set) + + Purpose: + + Free storage associated with a GSSAPI-generated gss_OID_set object. + The set parameter must refer to an OID-set that was returned from a + GSS-API routine. gss_release_oid_set() will free the storage + associated with each individual member OID, the OID set's elements + array, and the gss_OID_set_desc. + + Implementations are encouraged to set the gss_OID_set parameter to + GSS_C_NO_OID_SET on successful completion of this routine. + + Parameters: + + minor_status Integer, modify + Mechanism specific status code + + + + +Wray Standards Track [Page 74] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + set Set of Object IDs, modify + The storage associated with the gss_OID_set + will be deleted. + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + +5.30. gss_test_oid_set_member + + OM_uint32 gss_test_oid_set_member ( + OM_uint32 *minor_status, + const gss_OID member, + const gss_OID_set set, + int *present) + + Purpose: + + Interrogate an Object Identifier set to determine whether a specified + Object Identifier is a member. This routine is intended to be used + with OID sets returned by gss_indicate_mechs(), gss_acquire_cred(), + and gss_inquire_cred(), but will also work with user-generated sets. + + Parameters: + + minor_status Integer, modify + Mechanism specific status code + + member Object ID, read + The object identifier whose presence + is to be tested. + + set Set of Object ID, read + The Object Identifier set. + + present Boolean, modify + non-zero if the specified OID is a member + of the set, zero if not. + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + + + + + + + + +Wray Standards Track [Page 75] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +5.31. gss_unwrap + + OM_uint32 gss_unwrap ( + OM_uint32 *minor_status, + const gss_ctx_id_t context_handle, + const gss_buffer_t input_message_buffer, + gss_buffer_t output_message_buffer, + int *conf_state, + gss_qop_t *qop_state) + + Purpose: + + Converts a message previously protected by gss_wrap back to a usable + form, verifying the embedded MIC. The conf_state parameter indicates + whether the message was encrypted; the qop_state parameter indicates + the strength of protection that was used to provide the + confidentiality and integrity services. + + Since some application-level protocols may wish to use tokens emitted + by gss_wrap() to provide "secure framing", implementations must + support the wrapping and unwrapping of zero-length messages. + + Parameters: + + minor_status Integer, modify + Mechanism specific status code. + + context_handle gss_ctx_id_t, read + Identifies the context on which the message + arrived + + input_message_buffer buffer, opaque, read + protected message + + output_message_buffer buffer, opaque, modify + Buffer to receive unwrapped message. + Storage associated with this buffer must + be freed by the application after use use + with a call to gss_release_buffer(). + + conf_state boolean, modify, optional + Non-zero - Confidentiality and integrity + protection were used + Zero - Integrity service only was used + Specify NULL if not required + + + + + + +Wray Standards Track [Page 76] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + qop_state gss_qop_t, modify, optional + Quality of protection provided. + Specify NULL if not required + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_DEFECTIVE_TOKEN The token failed consistency checks + + GSS_S_BAD_SIG The MIC was incorrect + + GSS_S_DUPLICATE_TOKEN The token was valid, and contained a correct + MIC for the message, but it had already been + processed + + GSS_S_OLD_TOKEN The token was valid, and contained a correct MIC + for the message, but it is too old to check for + duplication. + + GSS_S_UNSEQ_TOKEN The token was valid, and contained a correct MIC + for the message, but has been verified out of + sequence; a later token has already been + received. + + GSS_S_GAP_TOKEN The token was valid, and contained a correct MIC + for the message, but has been verified out of + sequence; an earlier expected token has not yet + been received. + + GSS_S_CONTEXT_EXPIRED The context has already expired + + GSS_S_NO_CONTEXT The context_handle parameter did not identify + a valid context + +5.32. gss_verify_mic + + OM_uint32 gss_verify_mic ( + OM_uint32 *minor_status, + const gss_ctx_id_t context_handle, + const gss_buffer_t message_buffer, + const gss_buffer_t token_buffer, + gss_qop_t *qop_state) + + + + + + + + +Wray Standards Track [Page 77] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Purpose: + + Verifies that a cryptographic MIC, contained in the token parameter, + fits the supplied message. The qop_state parameter allows a message + recipient to determine the strength of protection that was applied to + the message. + + Since some application-level protocols may wish to use tokens emitted + by gss_wrap() to provide "secure framing", implementations must + support the calculation and verification of MICs over zero-length + messages. + + Parameters: + + minor_status Integer, modify + Mechanism specific status code. + + context_handle gss_ctx_id_t, read + Identifies the context on which the message + arrived + + message_buffer buffer, opaque, read + Message to be verified + + token_buffer buffer, opaque, read + Token associated with message + + qop_state gss_qop_t, modify, optional + quality of protection gained from MIC + Specify NULL if not required + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_DEFECTIVE_TOKEN The token failed consistency checks + + GSS_S_BAD_SIG The MIC was incorrect + + GSS_S_DUPLICATE_TOKEN The token was valid, and contained a correct + MIC for the message, but it had already been + processed + + GSS_S_OLD_TOKEN The token was valid, and contained a correct MIC + for the message, but it is too old to check for + duplication. + + + + + +Wray Standards Track [Page 78] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + GSS_S_UNSEQ_TOKEN The token was valid, and contained a correct MIC + for the message, but has been verified out of + sequence; a later token has already been received. + + GSS_S_GAP_TOKEN The token was valid, and contained a correct MIC + for the message, but has been verified out of + sequence; an earlier expected token has not yet + been received. + + GSS_S_CONTEXT_EXPIRED The context has already expired + + GSS_S_NO_CONTEXT The context_handle parameter did not identify a + valid context + +5.33. gss_wrap + + OM_uint32 gss_wrap ( + OM_uint32 *minor_status, + const gss_ctx_id_t context_handle, + int conf_req_flag, + gss_qop_t qop_req + const gss_buffer_t input_message_buffer, + int *conf_state, + gss_buffer_t output_message_buffer ) + + Purpose: + + Attaches a cryptographic MIC and optionally encrypts the specified + input_message. The output_message contains both the MIC and the + message. The qop_req parameter allows a choice between several + cryptographic algorithms, if supported by the chosen mechanism. + + Since some application-level protocols may wish to use tokens emitted + by gss_wrap() to provide "secure framing", implementations must + support the wrapping of zero-length messages. + + Parameters: + + minor_status Integer, modify + Mechanism specific status code. + + context_handle gss_ctx_id_t, read + Identifies the context on which the message + will be sent + + + + + + + +Wray Standards Track [Page 79] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + conf_req_flag boolean, read + Non-zero - Both confidentiality and integrity + services are requested + Zero - Only integrity service is requested + + qop_req gss_qop_t, read, optional + Specifies required quality of protection. A + mechanism-specific default may be requested by + setting qop_req to GSS_C_QOP_DEFAULT. If an + unsupported protection strength is requested, + gss_wrap will return a major_status of + GSS_S_BAD_QOP. + + input_message_buffer buffer, opaque, read + Message to be protected + + conf_state boolean, modify, optional + Non-zero - Confidentiality, data origin + authentication and integrity + services have been applied + Zero - Integrity and data origin services only + has been applied. + Specify NULL if not required + + output_message_buffer buffer, opaque, modify + Buffer to receive protected message. + Storage associated with this message must + be freed by the application after use with + a call to gss_release_buffer(). + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_CONTEXT_EXPIRED The context has already expired + + GSS_S_NO_CONTEXT The context_handle parameter did not identify a + valid context + + GSS_S_BAD_QOP The specified QOP is not supported by the + mechanism. + + + + + + + + + + +Wray Standards Track [Page 80] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +5.34. gss_wrap_size_limit + + OM_uint32 gss_wrap_size_limit ( + OM_uint32 *minor_status, + const gss_ctx_id_t context_handle, + int conf_req_flag, + gss_qop_t qop_req, + OM_uint32 req_output_size, + OM_uint32 *max_input_size) + + Purpose: + + Allows an application to determine the maximum message size that, if + presented to gss_wrap with the same conf_req_flag and qop_req + parameters, will result in an output token containing no more than + req_output_size bytes. + + This call is intended for use by applications that communicate over + protocols that impose a maximum message size. It enables the + application to fragment messages prior to applying protection. + + GSS-API implementations are recommended but not required to detect + invalid QOP values when gss_wrap_size_limit() is called. This routine + guarantees only a maximum message size, not the availability of + specific QOP values for message protection. + + Successful completion of this call does not guarantee that gss_wrap + will be able to protect a message of length max_input_size bytes, + since this ability may depend on the availability of system resources + at the time that gss_wrap is called. However, if the implementation + itself imposes an upper limit on the length of messages that may be + processed by gss_wrap, the implementation should not return a value + via max_input_bytes that is greater than this length. + + Parameters: + + minor_status Integer, modify + Mechanism specific status code + + context_handle gss_ctx_id_t, read + A handle that refers to the security over + which the messages will be sent. + + conf_req_flag Boolean, read + Indicates whether gss_wrap will be asked + to apply confidentiality protection in + + + + + +Wray Standards Track [Page 81] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + addition to integrity protection. See + the routine description for gss_wrap + for more details. + + qop_req gss_qop_t, read + Indicates the level of protection that + gss_wrap will be asked to provide. See + the routine description for gss_wrap for + more details. + + req_output_size Integer, read + The desired maximum size for tokens emitted + by gss_wrap. + + max_input_size Integer, modify + The maximum input message size that may + be presented to gss_wrap in order to + guarantee that the emitted token shall + be no larger than req_output_size bytes. + + Function value: GSS status code + + GSS_S_COMPLETE Successful completion + + GSS_S_NO_CONTEXT The referenced context could not be accessed. + + GSS_S_CONTEXT_EXPIRED The context has expired. + + GSS_S_BAD_QOP The specified QOP is not supported by the + mechanism. + +6. Security Considerations + + This document specifies a service interface for security facilities + and services; as such, security considerations appear throughout the + specification. Nonetheless, it is appropriate to summarize certain + specific points relevant to GSS-API implementors and calling + applications. Usage of the GSS-API interface does not in itself + provide security services or assurance; instead, these attributes are + dependent on the underlying mechanism(s) which support a GSS-API + implementation. Callers must be attentive to the requests made to + GSS-API calls and to the status indicators returned by GSS-API, as + these specify the security service characteristics which GSS-API will + provide. When the interprocess context transfer facility is used, + appropriate local controls should be applied to constrain access to + interprocess tokens and to the sensitive data which they contain. + + + + + +Wray Standards Track [Page 82] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + Appendix A. GSS-API C header file gssapi.h + + C-language GSS-API implementations should include a copy of the + following header-file. + + #ifndef GSSAPI_H_ + #define GSSAPI_H_ + + + + /* + * First, include stddef.h to get size_t defined. + */ + #include <stddef.h> + + /* + * If the platform supports the xom.h header file, it should be + * included here. + */ + #include <xom.h> + + + /* + * Now define the three implementation-dependent types. + */ + typedef <platform-specific> gss_ctx_id_t; + typedef <platform-specific> gss_cred_id_t; + typedef <platform-specific> gss_name_t; + + /* + * The following type must be defined as the smallest natural + * unsigned integer supported by the platform that has at least + * 32 bits of precision. + */ + typedef <platform-specific> gss_uint32; + + + #ifdef OM_STRING + /* + * We have included the xom.h header file. Verify that OM_uint32 + * is defined correctly. + */ + + #if sizeof(gss_uint32) != sizeof(OM_uint32) + #error Incompatible definition of OM_uint32 from xom.h + #endif + + typedef OM_object_identifier gss_OID_desc, *gss_OID; + + + +Wray Standards Track [Page 83] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + #else + + /* + * We can't use X/Open definitions, so roll our own. + */ + + typedef gss_uint32 OM_uint32; + + typedef struct gss_OID_desc_struct { + OM_uint32 length; + void *elements; + } gss_OID_desc, *gss_OID; + + #endif + + typedef struct gss_OID_set_desc_struct { + size_t count; + gss_OID elements; + } gss_OID_set_desc, *gss_OID_set; + + typedef struct gss_buffer_desc_struct { + size_t length; + void *value; + } gss_buffer_desc, *gss_buffer_t; + + typedef struct gss_channel_bindings_struct { + OM_uint32 initiator_addrtype; + gss_buffer_desc initiator_address; + OM_uint32 acceptor_addrtype; + gss_buffer_desc acceptor_address; + gss_buffer_desc application_data; + } *gss_channel_bindings_t; + + /* + * For now, define a QOP-type as an OM_uint32 + */ + typedef OM_uint32 gss_qop_t; + + typedef int gss_cred_usage_t; + + /* + * Flag bits for context-level services. + */ + + + + + + + + +Wray Standards Track [Page 84] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + #define GSS_C_DELEG_FLAG 1 + #define GSS_C_MUTUAL_FLAG 2 + #define GSS_C_REPLAY_FLAG 4 + #define GSS_C_SEQUENCE_FLAG 8 + #define GSS_C_CONF_FLAG 16 + #define GSS_C_INTEG_FLAG 32 + #define GSS_C_ANON_FLAG 64 + #define GSS_C_PROT_READY_FLAG 128 + #define GSS_C_TRANS_FLAG 256 + + /* + * Credential usage options + */ + #define GSS_C_BOTH 0 + #define GSS_C_INITIATE 1 + #define GSS_C_ACCEPT 2 + + /* + * Status code types for gss_display_status + */ + #define GSS_C_GSS_CODE 1 + #define GSS_C_MECH_CODE 2 + + /* + * The constant definitions for channel-bindings address families + */ + #define GSS_C_AF_UNSPEC 0 + #define GSS_C_AF_LOCAL 1 + #define GSS_C_AF_INET 2 + #define GSS_C_AF_IMPLINK 3 + #define GSS_C_AF_PUP 4 + #define GSS_C_AF_CHAOS 5 + #define GSS_C_AF_NS 6 + #define GSS_C_AF_NBS 7 + #define GSS_C_AF_ECMA 8 + #define GSS_C_AF_DATAKIT 9 + #define GSS_C_AF_CCITT 10 + #define GSS_C_AF_SNA 11 + #define GSS_C_AF_DECnet 12 + #define GSS_C_AF_DLI 13 + #define GSS_C_AF_LAT 14 + #define GSS_C_AF_HYLINK 15 + #define GSS_C_AF_APPLETALK 16 + #define GSS_C_AF_BSC 17 + #define GSS_C_AF_DSS 18 + #define GSS_C_AF_OSI 19 + #define GSS_C_AF_X25 21 + + + + +Wray Standards Track [Page 85] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + #define GSS_C_AF_NULLADDR 255 + + /* + * Various Null values + */ + #define GSS_C_NO_NAME ((gss_name_t) 0) + #define GSS_C_NO_BUFFER ((gss_buffer_t) 0) + #define GSS_C_NO_OID ((gss_OID) 0) + #define GSS_C_NO_OID_SET ((gss_OID_set) 0) + #define GSS_C_NO_CONTEXT ((gss_ctx_id_t) 0) + #define GSS_C_NO_CREDENTIAL ((gss_cred_id_t) 0) + #define GSS_C_NO_CHANNEL_BINDINGS ((gss_channel_bindings_t) 0) + #define GSS_C_EMPTY_BUFFER {0, NULL} + + /* + * Some alternate names for a couple of the above + * values. These are defined for V1 compatibility. + */ + #define GSS_C_NULL_OID GSS_C_NO_OID + #define GSS_C_NULL_OID_SET GSS_C_NO_OID_SET + + /* + * Define the default Quality of Protection for per-message + * services. Note that an implementation that offers multiple + * levels of QOP may define GSS_C_QOP_DEFAULT to be either zero + * (as done here) to mean "default protection", or to a specific + * explicit QOP value. However, a value of 0 should always be + * interpreted by a GSS-API implementation as a request for the + * default protection level. + */ + #define GSS_C_QOP_DEFAULT 0 + + /* + * Expiration time of 2^32-1 seconds means infinite lifetime for a + * credential or security context + */ + #define GSS_C_INDEFINITE 0xfffffffful + + /* + * The implementation must reserve static storage for a + * gss_OID_desc object containing the value + * {10, (void *)"\x2a\x86\x48\x86\xf7\x12" + * "\x01\x02\x01\x01"}, + * corresponding to an object-identifier value of + * {iso(1) member-body(2) United States(840) mit(113554) + * infosys(1) gssapi(2) generic(1) user_name(1)}. The constant + * GSS_C_NT_USER_NAME should be initialized to point + * to that gss_OID_desc. + + + +Wray Standards Track [Page 86] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + */ + extern gss_OID GSS_C_NT_USER_NAME; + + /* + * The implementation must reserve static storage for a + * gss_OID_desc object containing the value + * {10, (void *)"\x2a\x86\x48\x86\xf7\x12" + * "\x01\x02\x01\x02"}, + * corresponding to an object-identifier value of + * {iso(1) member-body(2) United States(840) mit(113554) + * infosys(1) gssapi(2) generic(1) machine_uid_name(2)}. + * The constant GSS_C_NT_MACHINE_UID_NAME should be + * initialized to point to that gss_OID_desc. + */ + extern gss_OID GSS_C_NT_MACHINE_UID_NAME; + + /* + * The implementation must reserve static storage for a + * gss_OID_desc object containing the value + * {10, (void *)"\x2a\x86\x48\x86\xf7\x12" + * "\x01\x02\x01\x03"}, + * corresponding to an object-identifier value of + * {iso(1) member-body(2) United States(840) mit(113554) + * infosys(1) gssapi(2) generic(1) string_uid_name(3)}. + * The constant GSS_C_NT_STRING_UID_NAME should be + * initialized to point to that gss_OID_desc. + */ + extern gss_OID GSS_C_NT_STRING_UID_NAME; + + /* + * The implementation must reserve static storage for a + * gss_OID_desc object containing the value + * {6, (void *)"\x2b\x06\x01\x05\x06\x02"}, + * corresponding to an object-identifier value of + * {iso(1) org(3) dod(6) internet(1) security(5) + * nametypes(6) gss-host-based-services(2)). The constant + * GSS_C_NT_HOSTBASED_SERVICE_X should be initialized to point + * to that gss_OID_desc. This is a deprecated OID value, and + * implementations wishing to support hostbased-service names + * should instead use the GSS_C_NT_HOSTBASED_SERVICE OID, + * defined below, to identify such names; + * GSS_C_NT_HOSTBASED_SERVICE_X should be accepted a synonym + * for GSS_C_NT_HOSTBASED_SERVICE when presented as an input + * parameter, but should not be emitted by GSS-API + * implementations + */ + extern gss_OID GSS_C_NT_HOSTBASED_SERVICE_X; + + + + +Wray Standards Track [Page 87] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + /* + * The implementation must reserve static storage for a + * gss_OID_desc object containing the value + * {10, (void *)"\x2a\x86\x48\x86\xf7\x12" + * "\x01\x02\x01\x04"}, corresponding to an + * object-identifier value of {iso(1) member-body(2) + * Unites States(840) mit(113554) infosys(1) gssapi(2) + * generic(1) service_name(4)}. The constant + * GSS_C_NT_HOSTBASED_SERVICE should be initialized + * to point to that gss_OID_desc. + */ + extern gss_OID GSS_C_NT_HOSTBASED_SERVICE; + + /* + * The implementation must reserve static storage for a + * gss_OID_desc object containing the value + * {6, (void *)"\x2b\x06\01\x05\x06\x03"}, + * corresponding to an object identifier value of + * {1(iso), 3(org), 6(dod), 1(internet), 5(security), + * 6(nametypes), 3(gss-anonymous-name)}. The constant + * and GSS_C_NT_ANONYMOUS should be initialized to point + * to that gss_OID_desc. + */ + extern gss_OID GSS_C_NT_ANONYMOUS; + + + /* + * The implementation must reserve static storage for a + * gss_OID_desc object containing the value + * {6, (void *)"\x2b\x06\x01\x05\x06\x04"}, + * corresponding to an object-identifier value of + * {1(iso), 3(org), 6(dod), 1(internet), 5(security), + * 6(nametypes), 4(gss-api-exported-name)}. The constant + * GSS_C_NT_EXPORT_NAME should be initialized to point + * to that gss_OID_desc. + */ + extern gss_OID GSS_C_NT_EXPORT_NAME; + + + /* Major status codes */ + + #define GSS_S_COMPLETE 0 + + /* + * Some "helper" definitions to make the status code macros obvious. + */ + #define GSS_C_CALLING_ERROR_OFFSET 24 + #define GSS_C_ROUTINE_ERROR_OFFSET 16 + + + +Wray Standards Track [Page 88] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + #define GSS_C_SUPPLEMENTARY_OFFSET 0 + #define GSS_C_CALLING_ERROR_MASK 0377ul + #define GSS_C_ROUTINE_ERROR_MASK 0377ul + #define GSS_C_SUPPLEMENTARY_MASK 0177777ul + + /* + * The macros that test status codes for error conditions. + * Note that the GSS_ERROR() macro has changed slightly from + * the V1 GSS-API so that it now evaluates its argument + * only once. + */ + #define GSS_CALLING_ERROR(x) \ + (x & (GSS_C_CALLING_ERROR_MASK << GSS_C_CALLING_ERROR_OFFSET)) + #define GSS_ROUTINE_ERROR(x) \ + (x & (GSS_C_ROUTINE_ERROR_MASK << GSS_C_ROUTINE_ERROR_OFFSET)) + #define GSS_SUPPLEMENTARY_INFO(x) \ + (x & (GSS_C_SUPPLEMENTARY_MASK << GSS_C_SUPPLEMENTARY_OFFSET)) + #define GSS_ERROR(x) \ + (x & ((GSS_C_CALLING_ERROR_MASK << GSS_C_CALLING_ERROR_OFFSET) | \ + (GSS_C_ROUTINE_ERROR_MASK << GSS_C_ROUTINE_ERROR_OFFSET))) + + /* + * Now the actual status code definitions + */ + + /* + * Calling errors: + + */ + #define GSS_S_CALL_INACCESSIBLE_READ \ + (1ul << GSS_C_CALLING_ERROR_OFFSET) + #define GSS_S_CALL_INACCESSIBLE_WRITE \ + (2ul << GSS_C_CALLING_ERROR_OFFSET) + #define GSS_S_CALL_BAD_STRUCTURE \ + (3ul << GSS_C_CALLING_ERROR_OFFSET) + + /* + * Routine errors: + */ + #define GSS_S_BAD_MECH (1ul << + GSS_C_ROUTINE_ERROR_OFFSET) + #define GSS_S_BAD_NAME (2ul << + GSS_C_ROUTINE_ERROR_OFFSET) + #define GSS_S_BAD_NAMETYPE (3ul << + GSS_C_ROUTINE_ERROR_OFFSET) + #define GSS_S_BAD_BINDINGS (4ul << + GSS_C_ROUTINE_ERROR_OFFSET) + #define GSS_S_BAD_STATUS (5ul << + + + +Wray Standards Track [Page 89] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + GSS_C_ROUTINE_ERROR_OFFSET) + #define GSS_S_BAD_SIG (6ul << + GSS_C_ROUTINE_ERROR_OFFSET) + #define GSS_S_BAD_MIC GSS_S_BAD_SIG + #define GSS_S_NO_CRED (7ul << + GSS_C_ROUTINE_ERROR_OFFSET) + #define GSS_S_NO_CONTEXT (8ul << + GSS_C_ROUTINE_ERROR_OFFSET) + #define GSS_S_DEFECTIVE_TOKEN (9ul << + GSS_C_ROUTINE_ERROR_OFFSET) + #define GSS_S_DEFECTIVE_CREDENTIAL (10ul << + GSS_C_ROUTINE_ERROR_OFFSET) + #define GSS_S_CREDENTIALS_EXPIRED (11ul << + GSS_C_ROUTINE_ERROR_OFFSET) + #define GSS_S_CONTEXT_EXPIRED (12ul << + GSS_C_ROUTINE_ERROR_OFFSET) + #define GSS_S_FAILURE (13ul << + GSS_C_ROUTINE_ERROR_OFFSET) + #define GSS_S_BAD_QOP (14ul << + GSS_C_ROUTINE_ERROR_OFFSET) + #define GSS_S_UNAUTHORIZED (15ul << + GSS_C_ROUTINE_ERROR_OFFSET) + #define GSS_S_UNAVAILABLE (16ul << + GSS_C_ROUTINE_ERROR_OFFSET) + #define GSS_S_DUPLICATE_ELEMENT (17ul << + GSS_C_ROUTINE_ERROR_OFFSET) + #define GSS_S_NAME_NOT_MN (18ul << + GSS_C_ROUTINE_ERROR_OFFSET) + + /* + * Supplementary info bits: + */ + #define GSS_S_CONTINUE_NEEDED \ + (1ul << (GSS_C_SUPPLEMENTARY_OFFSET + 0)) + #define GSS_S_DUPLICATE_TOKEN \ + (1ul << (GSS_C_SUPPLEMENTARY_OFFSET + 1)) + #define GSS_S_OLD_TOKEN \ + (1ul << (GSS_C_SUPPLEMENTARY_OFFSET + 2)) + #define GSS_S_UNSEQ_TOKEN \ + (1ul << (GSS_C_SUPPLEMENTARY_OFFSET + 3)) + #define GSS_S_GAP_TOKEN \ + (1ul << (GSS_C_SUPPLEMENTARY_OFFSET + 4)) + + /* + * Finally, function prototypes for the GSS-API routines. + */ + + + + + +Wray Standards Track [Page 90] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + OM_uint32 gss_acquire_cred + (OM_uint32 , /* minor_status */ + const gss_name_t, /* desired_name */ + OM_uint32, /* time_req */ + const gss_OID_set, /* desired_mechs */ + gss_cred_usage_t, /* cred_usage */ + gss_cred_id_t , /* output_cred_handle */ + gss_OID_set , /* actual_mechs */ + OM_uint32 * /* time_rec */ + ); + + OM_uint32 gss_release_cred + (OM_uint32 , /* minor_status */ + gss_cred_id_t * /* cred_handle */ + ); + + OM_uint32 gss_init_sec_context + (OM_uint32 , /* minor_status */ + const gss_cred_id_t, /* initiator_cred_handle */ + gss_ctx_id_t , /* context_handle */ + const gss_name_t, /* target_name */ + const gss_OID, /* mech_type */ + OM_uint32, /* req_flags */ + OM_uint32, /* time_req */ + const gss_channel_bindings_t, + /* input_chan_bindings */ + const gss_buffer_t, /* input_token */ + gss_OID , /* actual_mech_type */ + gss_buffer_t, /* output_token */ + OM_uint32 , /* ret_flags */ + OM_uint32 * /* time_rec */ + ); + + OM_uint32 gss_accept_sec_context + (OM_uint32 , /* minor_status */ + gss_ctx_id_t , /* context_handle */ + const gss_cred_id_t, /* acceptor_cred_handle */ + const gss_buffer_t, /* input_token_buffer */ + const gss_channel_bindings_t, + /* input_chan_bindings */ + gss_name_t , /* src_name */ + gss_OID , /* mech_type */ + gss_buffer_t, /* output_token */ + OM_uint32 , /* ret_flags */ + OM_uint32 , /* time_rec */ + gss_cred_id_t * /* delegated_cred_handle */ + ); + + + + +Wray Standards Track [Page 91] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + OM_uint32 gss_process_context_token + (OM_uint32 , /* minor_status */ + const gss_ctx_id_t, /* context_handle */ + const gss_buffer_t /* token_buffer */ + ); + + OM_uint32 gss_delete_sec_context + (OM_uint32 , /* minor_status */ + gss_ctx_id_t , /* context_handle */ + gss_buffer_t /* output_token */ + ); + + OM_uint32 gss_context_time + (OM_uint32 , /* minor_status */ + const gss_ctx_id_t, /* context_handle */ + OM_uint32 * /* time_rec */ + ); + + OM_uint32 gss_get_mic + (OM_uint32 , /* minor_status */ + const gss_ctx_id_t, /* context_handle */ + gss_qop_t, /* qop_req */ + const gss_buffer_t, /* message_buffer */ + gss_buffer_t /* message_token */ + ); + + OM_uint32 gss_verify_mic + (OM_uint32 , /* minor_status */ + const gss_ctx_id_t, /* context_handle */ + const gss_buffer_t, /* message_buffer */ + const gss_buffer_t, /* token_buffer */ + gss_qop_t * /* qop_state */ + ); + + OM_uint32 gss_wrap + (OM_uint32 , /* minor_status */ + const gss_ctx_id_t, /* context_handle */ + int, /* conf_req_flag */ + gss_qop_t, /* qop_req */ + const gss_buffer_t, /* input_message_buffer */ + int , /* conf_state */ + gss_buffer_t /* output_message_buffer */ + ); + + + + + + + + +Wray Standards Track [Page 92] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + OM_uint32 gss_unwrap + (OM_uint32 , /* minor_status */ + const gss_ctx_id_t, /* context_handle */ + const gss_buffer_t, /* input_message_buffer */ + gss_buffer_t, /* output_message_buffer */ + int , /* conf_state */ + gss_qop_t * /* qop_state */ + ); + + + + OM_uint32 gss_display_status + (OM_uint32 , /* minor_status */ + OM_uint32, /* status_value */ + int, /* status_type */ + const gss_OID, /* mech_type */ + OM_uint32 , /* message_context */ + gss_buffer_t /* status_string */ + ); + + OM_uint32 gss_indicate_mechs + (OM_uint32 , /* minor_status */ + gss_OID_set * /* mech_set */ + ); + + OM_uint32 gss_compare_name + (OM_uint32 , /* minor_status */ + const gss_name_t, /* name1 */ + const gss_name_t, /* name2 */ + int * /* name_equal */ + ); + + OM_uint32 gss_display_name + (OM_uint32 , /* minor_status */ + const gss_name_t, /* input_name */ + gss_buffer_t, /* output_name_buffer */ + gss_OID * /* output_name_type */ + ); + + OM_uint32 gss_import_name + (OM_uint32 , /* minor_status */ + const gss_buffer_t, /* input_name_buffer */ + const gss_OID, /* input_name_type */ + gss_name_t * /* output_name */ + ); + + + + + + +Wray Standards Track [Page 93] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + OM_uint32 gss_export_name + (OM_uint32, /* minor_status */ + const gss_name_t, /* input_name */ + gss_buffer_t /* exported_name */ + ); + + OM_uint32 gss_release_name + (OM_uint32 *, /* minor_status */ + gss_name_t * /* input_name */ + ); + + OM_uint32 gss_release_buffer + (OM_uint32 , /* minor_status */ + gss_buffer_t /* buffer */ + ); + + OM_uint32 gss_release_oid_set + (OM_uint32 , /* minor_status */ + gss_OID_set * /* set */ + ); + + OM_uint32 gss_inquire_cred + (OM_uint32 , /* minor_status */ + const gss_cred_id_t, /* cred_handle */ + gss_name_t , /* name */ + OM_uint32 , /* lifetime */ + gss_cred_usage_t , /* cred_usage */ + gss_OID_set * /* mechanisms */ + ); + + OM_uint32 gss_inquire_context ( + OM_uint32 , /* minor_status */ + const gss_ctx_id_t, /* context_handle */ + gss_name_t , /* src_name */ + gss_name_t , /* targ_name */ + OM_uint32 , /* lifetime_rec */ + gss_OID , /* mech_type */ + OM_uint32 , /* ctx_flags */ + int , /* locally_initiated */ + int * /* open */ + ); + + + + + + + + + + +Wray Standards Track [Page 94] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + OM_uint32 gss_wrap_size_limit ( + OM_uint32 , /* minor_status */ + const gss_ctx_id_t, /* context_handle */ + int, /* conf_req_flag */ + gss_qop_t, /* qop_req */ + OM_uint32, /* req_output_size */ + OM_uint32 * /* max_input_size */ + ); + + OM_uint32 gss_add_cred ( + OM_uint32 , /* minor_status */ + const gss_cred_id_t, /* input_cred_handle */ + const gss_name_t, /* desired_name */ + const gss_OID, /* desired_mech */ + gss_cred_usage_t, /* cred_usage */ + OM_uint32, /* initiator_time_req */ + OM_uint32, /* acceptor_time_req */ + gss_cred_id_t , /* output_cred_handle */ + gss_OID_set , /* actual_mechs */ + OM_uint32 , /* initiator_time_rec */ + OM_uint32 * /* acceptor_time_rec */ + ); + + OM_uint32 gss_inquire_cred_by_mech ( + OM_uint32 , /* minor_status */ + const gss_cred_id_t, /* cred_handle */ + const gss_OID, /* mech_type */ + gss_name_t , /* name */ + OM_uint32 , /* initiator_lifetime */ + OM_uint32 , /* acceptor_lifetime */ + gss_cred_usage_t * /* cred_usage */ + ); + + OM_uint32 gss_export_sec_context ( + OM_uint32 , /* minor_status */ + gss_ctx_id_t , /* context_handle */ + gss_buffer_t /* interprocess_token */ + ); + + OM_uint32 gss_import_sec_context ( + OM_uint32 , /* minor_status */ + const gss_buffer_t, /* interprocess_token */ + gss_ctx_id_t * /* context_handle */ + ); + + + + + + + +Wray Standards Track [Page 95] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + OM_uint32 gss_create_empty_oid_set ( + OM_uint32 , /* minor_status */ + gss_OID_set * /* oid_set */ + ); + + OM_uint32 gss_add_oid_set_member ( + OM_uint32 , /* minor_status */ + const gss_OID, /* member_oid */ + gss_OID_set * /* oid_set */ + ); + + OM_uint32 gss_test_oid_set_member ( + OM_uint32 , /* minor_status */ + const gss_OID, /* member */ + const gss_OID_set, /* set */ + int * /* present */ + ); + + OM_uint32 gss_inquire_names_for_mech ( + OM_uint32 , /* minor_status */ + const gss_OID, /* mechanism */ + gss_OID_set * /* name_types */ + ); + + OM_uint32 gss_inquire_mechs_for_name ( + OM_uint32 , /* minor_status */ + const gss_name_t, /* input_name */ + gss_OID_set * /* mech_types */ + ); + + OM_uint32 gss_canonicalize_name ( + OM_uint32 , /* minor_status */ + const gss_name_t, /* input_name */ + const gss_OID, /* mech_type */ + gss_name_t * /* output_name */ + ); + + OM_uint32 gss_duplicate_name ( + OM_uint32 , /* minor_status */ + const gss_name_t, /* src_name */ + gss_name_t * /* dest_name */ + ); + + /* + * The following routines are obsolete variants of gss_get_mic, + * gss_verify_mic, gss_wrap and gss_unwrap. They should be + * provided by GSS-API V2 implementations for backwards + * compatibility with V1 applications. Distinct entrypoints + + + +Wray Standards Track [Page 96] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + * (as opposed to #defines) should be provided, both to allow + * GSS-API V1 applications to link against GSS-API V2 + implementations, + * and to retain the slight parameter type differences between the + * obsolete versions of these routines and their current forms. + */ + + OM_uint32 gss_sign + (OM_uint32 , /* minor_status */ + gss_ctx_id_t, /* context_handle */ + int, /* qop_req */ + gss_buffer_t, /* message_buffer */ + gss_buffer_t /* message_token */ + ); + + + OM_uint32 gss_verify + (OM_uint32 , /* minor_status */ + gss_ctx_id_t, /* context_handle */ + gss_buffer_t, /* message_buffer */ + gss_buffer_t, /* token_buffer */ + int * /* qop_state */ + ); + + OM_uint32 gss_seal + (OM_uint32 , /* minor_status */ + gss_ctx_id_t, /* context_handle */ + int, /* conf_req_flag */ + int, /* qop_req */ + gss_buffer_t, /* input_message_buffer */ + int , /* conf_state */ + gss_buffer_t /* output_message_buffer */ + ); + + + OM_uint32 gss_unseal + (OM_uint32 , /* minor_status */ + gss_ctx_id_t, /* context_handle */ + gss_buffer_t, /* input_message_buffer */ + gss_buffer_t, /* output_message_buffer */ + int , /* conf_state */ + int * /* qop_state */ + ); + + #endif /* GSSAPI_H_ */ + + + + + + +Wray Standards Track [Page 97] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +Appendix B. Additional constraints for application binary portability + + The purpose of this C-bindings document is to encourage source-level + portability of applications across GSS-API implementations on + different platforms and atop different mechanisms. Additional goals + that have not been explicitly addressed by this document are link- + time and run-time portability. + + Link-time portability provides the ability to compile an application + against one implementation of GSS-API, and then link it against a + different implementation on the same platform. It is a stricter + requirement than source-level portability. + + Run-time portability differs from link-time portability only on those + platforms that implement dynamically loadable GSS-API + implementations, but do not offer load-time symbol resolution. On + such platforms, run-time portability is a stricter requirement than + link-time portability, and will typically include the precise + placement of the various GSS-API routines within library entrypoint + vectors. + + Individual platforms will impose their own rules that must be + followed to achieve link-time (and run-time, if different) + portability. In order to ensure either form of binary portability, + an ABI specification must be written for GSS-API implementations on + that platform. However, it is recognized that there are some issues + that are likely to be common to all such ABI specifications. This + appendix is intended to be a repository for such common issues, and + contains some suggestions that individual ABI specifications may + choose to reference. Since machine architectures vary greatly, it may + not be possible or desirable to follow these suggestions on all + platforms. + +B.1. Pointers + + While ANSI-C provides a single pointer type for each declared type, + plus a single (void *) type, some platforms (notably those using + segmented memory architectures) augment this with various modified + pointer types (e.g. far pointers, near pointers). These language + bindings assume ANSI-C, and thus do not address such non-standard + implementations. GSS-API implementations for such platforms must + choose an appropriate memory model, and should use it consistently + throughout. For example, if a memory model is chosen that requires + the use of far pointers when passing routine parameters, then far + pointers should also be used within the structures defined by GSS- + API. + + + + + +Wray Standards Track [Page 98] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +B.2. Internal structure alignment + + GSS-API defines several data-structures containing differently-sized + fields. An ABI specification should include a detailed description + of how the fields of such structures are aligned, and if there is any + internal padding in these data structures. The use of compiler + defaults for the platform is recommended. + +B.3. Handle types + + The C bindings specify that the gss_cred_id_t and gss_ctx_id_t types + should be implemented as either pointer or arithmetic types, and that + if pointer types are used, care should be taken to ensure that two + handles may be compared with the == operator. Note that ANSI-C does + not guarantee that two pointer values may be compared with the == + operator unless either the two pointers point to members of a single + array, or at least one of the pointers contains a NULL value. + + For binary portability, additional constraints are required. The + following is an attempt at defining platform-independent constraints. + + The size of the handle type must be the same as sizeof(void *), using + the appropriate memory model. + + The == operator for the chosen type must be a simple bit-wise + comparison. That is, for two in-memory handle objects h1 and h2, the + boolean value of the expression + + (h1 == h2) + + should always be the same as the boolean value of the expression + + (memcmp(&h1, &h2, sizeof(h1)) == 0) + + The actual use of the type (void *) for handle types is discouraged, + not for binary portability reasons, but since it effectively disables + much of the compile-time type-checking that the compiler can + otherwise perform, and is therefore not "programmer-friendly". If a + pointer implementation is desired, and if the platform's + implementation of pointers permits, the handles should be implemented + as pointers to distinct implementation-defined types. + +B.4. The gss_name_t type + + The gss_name_t type, representing the internal name object, should be + implemented as a pointer type. The use of the (void *) type is + discouraged as it does not allow the compiler to perform strong + type-checking. However, the pointer type chosen should be of the + + + +Wray Standards Track [Page 99] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + + same size as the (void *) type. Provided this rule is obeyed, ABI + specifications need not further constrain the implementation of + gss_name_t objects. + +B.5. The int and size_t types + + Some platforms may support differently sized implementations of the + "int" and "size_t" types, perhaps chosen through compiler switches, + and perhaps dependent on memory model. An ABI specification for such + a platform should include required implementations for these types. + It is recommended that the default implementation (for the chosen + memory model, if appropriate) is chosen. + +B.6. Procedure-calling conventions + + Some platforms support a variety of different binary conventions for + calling procedures. Such conventions cover things like the format of + the stack frame, the order in which the routine parameters are pushed + onto the stack, whether or not a parameter count is pushed onto the + stack, whether some argument(s) or return values are to be passed in + registers, and whether the called routine or the caller is + responsible for removing the stack frame on return. For such + platforms, an ABI specification should specify which calling + convention is to be used for GSS-API implementations. + +References + + [GSSAPI] Linn, J., "Generic Security Service Application Program + Interface Version 2, Update 1", RFC 2743, January 2000. + + [XOM] OSI Object Management API Specification, Version 2.0 t", + X.400 API Association & X/Open Company Limited, August + 24, 1990 Specification of datatypes and routines for + manipulating information objects. + +Author's Address + + John Wray + Iris Associates + 5 Technology Park Drive, + Westford, MA 01886 + USA + + Phone: +1-978-392-6689 + EMail: John_Wray@Iris.com + + + + + + +Wray Standards Track [Page 100] + +RFC 2744 GSS-API V2: C-bindings January 2000 + + +Full Copyright Statement + + Copyright (C) The Internet Society (2000). All Rights Reserved. + + This document and translations of it may be copied and furnished to + others, and derivative works that comment on or otherwise explain it + or assist in its implementation may be prepared, copied, published + and distributed, in whole or in part, without restriction of any + kind, provided that the above copyright notice and this paragraph are + included on all such copies and derivative works. However, this + document itself may not be modified in any way, such as by removing + the copyright notice or references to the Internet Society or other + Internet organizations, except as needed for the purpose of + developing Internet standards in which case the procedures for + copyrights defined in the Internet Standards process must be + followed, or as required to translate it into languages other than + English. + + The limited permissions granted above are perpetual and will not be + revoked by the Internet Society or its successors or assigns. + + This document and the information contained herein is provided on an + "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING + TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING + BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION + HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF + MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. + +Acknowledgement + + Funding for the RFC Editor function is currently provided by the + Internet Society. + + + + + + + + + + + + + + + + + + + +Wray Standards Track [Page 101] + |