summaryrefslogtreecommitdiff
path: root/doc/rfc/rfc6210.txt
diff options
context:
space:
mode:
Diffstat (limited to 'doc/rfc/rfc6210.txt')
-rw-r--r--doc/rfc/rfc6210.txt787
1 files changed, 787 insertions, 0 deletions
diff --git a/doc/rfc/rfc6210.txt b/doc/rfc/rfc6210.txt
new file mode 100644
index 0000000..986af36
--- /dev/null
+++ b/doc/rfc/rfc6210.txt
@@ -0,0 +1,787 @@
+
+
+
+
+
+
+Internet Engineering Task Force (IETF) J. Schaad
+Request for Comments: 6210 Soaring Hawk Consulting
+Category: Experimental April 2011
+ISSN: 2070-1721
+
+
+ Experiment: Hash Functions with Parameters
+ in the Cryptographic Message Syntax (CMS) and S/MIME
+
+Abstract
+
+ New hash algorithms are being developed that may include parameters.
+ Cryptographic Message Syntax (CMS) has not currently defined any hash
+ algorithms with parameters, but anecdotal evidence suggests that
+ defining one could cause major problems. This document defines just
+ such an algorithm and describes how to use it so that experiments can
+ be run to find out how bad including hash parameters will be.
+
+Status of This Memo
+
+ This document is not an Internet Standards Track specification; it is
+ published for examination, experimental implementation, and
+ evaluation.
+
+ This document defines an Experimental Protocol for the Internet
+ community. This document is a product of the Internet Engineering
+ Task Force (IETF). It represents the consensus of the IETF
+ community. It has received public review and has been approved for
+ publication by the Internet Engineering Steering Group (IESG). Not
+ all documents approved by the IESG are a candidate for any level of
+ Internet Standard; see Section 2 of RFC 5741.
+
+ Information about the current status of this document, any errata,
+ and how to provide feedback on it may be obtained at
+ http://www.rfc-editor.org/info/rfc6210.
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+Schaad Experimental [Page 1]
+
+RFC 6210 CMS Parameterized Hash April 2011
+
+
+Copyright Notice
+
+ Copyright (c) 2011 IETF Trust and the persons identified as the
+ document authors. All rights reserved.
+
+ This document is subject to BCP 78 and the IETF Trust's Legal
+ Provisions Relating to IETF Documents
+ (http://trustee.ietf.org/license-info) in effect on the date of
+ publication of this document. Please review these documents
+ carefully, as they describe your rights and restrictions with respect
+ to this document. Code Components extracted from this document must
+ include Simplified BSD License text as described in Section 4.e of
+ the Trust Legal Provisions and are provided without warranty as
+ described in the Simplified BSD License.
+
+Table of Contents
+
+ 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
+ 1.1. Notation . . . . . . . . . . . . . . . . . . . . . . . . . 5
+ 2. XOR-MD5 Digest Algorithm . . . . . . . . . . . . . . . . . . . 5
+ 3. ASN.1 Encoding . . . . . . . . . . . . . . . . . . . . . . . . 6
+ 4. CMS ASN.1 Handling . . . . . . . . . . . . . . . . . . . . . . 6
+ 5. MIME Handling . . . . . . . . . . . . . . . . . . . . . . . . 6
+ 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
+ 7. Security Considerations . . . . . . . . . . . . . . . . . . . 7
+ 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 7
+ 8.1. Normative References . . . . . . . . . . . . . . . . . . . 7
+ 8.2. Informative References . . . . . . . . . . . . . . . . . . 8
+ Appendix A. Examples . . . . . . . . . . . . . . . . . . . . . . 9
+ A.1. Encapsulated Signed Data Example . . . . . . . . . . . . . 9
+ A.2. Multipart Signed Message . . . . . . . . . . . . . . . . . 10
+ A.3. Authenticated Data Example . . . . . . . . . . . . . . . . 12
+ Appendix B. 2008 ASN.1 Module . . . . . . . . . . . . . . . . . . 13
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+Schaad Experimental [Page 2]
+
+RFC 6210 CMS Parameterized Hash April 2011
+
+
+1. Introduction
+
+ At the present time, all hash algorithms that are used in
+ Cryptographic Message Syntax (CMS) implementations are defined as
+ having no parameters. Anecdotal evidence suggests that if a hash
+ algorithm is defined that does require the presence of parameters,
+ there may be extensive problems. This document presents the details
+ needed to run an experiment so that the community can find out just
+ how bad the situation really is and, if needed, either make drastic
+ changes in implementations or make sure that any hash algorithms
+ chosen do not have parameters.
+
+ In CMS data structures, hash algorithms currently exist in the
+ following locations:
+
+ o SignerInfo.digestAlgorithm - holds the digest algorithm used to
+ compute the hash value over the content.
+
+ o DigestedData.digestAlgorithm - holds the digest algorithm used to
+ compute the hash value over the content.
+
+ o AuthenticatedData.digestAlgorithm - holds the digest algorithm
+ used to compute the hash value over the content.
+
+ o SignedData.digestAlgorithms - an optional location to hold the set
+ of digest algorithms used in computing the hash value over the
+ content.
+
+ o multipart/signed micalg - holds a textual indicator of the hash
+ algorithm for multipart signed MIME messages.
+
+ The first three locations hold the identification of a single hash,
+ and would hold the parameters for that hash. It's mandatory to fill
+ these fields.
+
+ The ASN.1 structures defined for the DigestedData and
+ AuthenticatedData types place the digest algorithm field before the
+ encapsulated data field. This means that the hash algorithm
+ (including the parameters) is fully defined, and therfore can be
+ instantiated, before the hash function would start hashing the
+ encapsulated data.
+
+ In the ASN.1 defined for the SignedData type, the value of
+ SignerInfo.digestAlgorithm is not seen until the content has been
+ processed. This is the reason for the existence of the
+ SignedData.digestAlgorithms field, so that the set of all digest
+ algorithms used can be seen prior to the content being processed. It
+ is not currently mandatory to fill in this field, and the signature
+
+
+
+Schaad Experimental [Page 3]
+
+RFC 6210 CMS Parameterized Hash April 2011
+
+
+ validation process is supposed to succeed even if this field is
+ absent. (RFC 5652 says signature validation MAY fail if the digest
+ algorithm is absent.)
+
+ For the case of detached content, the ASN.1 structures need to be
+ processed before processing the detached content in order to obtain
+ the parameters of the hash function. The MIME multipart/signature
+ content type attempts to avoid this problem by defining a micalg
+ field that contains the set of hash algorithms (with parameters) so
+ that the hash functions can be set up prior to processing the
+ content.
+
+ When processing multipart/signed messages, two paths exists:
+
+ 1. Process the message content before the ASN.1. The steps involved
+ are:
+
+ * Get a set of hash functions by looking at the micalg parameter
+ and potentially add a set of generic algorithms.
+
+ * Create a hasher for each of those algorithms.
+
+ * Hash the message content (the first part of the multipart).
+
+ * Process the ASN.1 and have a potential failure point if a hash
+ algorithm is required but was not computed.
+
+ 2. Process the message content after the ASN.1. The steps involved
+ are:
+
+ * Save the message content for later processing.
+
+ * Parse the ASN.1 and build a list of hash functions based on
+ its content.
+
+ * Create a hasher for each of those algorithms.
+
+ * Hash the saved message content.
+
+ * Perform the signature validation.
+
+ The first path allows for single-pass processing, but has the
+ potential that a fallback path needs to be added in some cases. The
+ second path does not need a fallback path, but does not allow for
+ single-pass processing.
+
+
+
+
+
+
+Schaad Experimental [Page 4]
+
+RFC 6210 CMS Parameterized Hash April 2011
+
+
+ The fallback path above may also be needed for the encapsulated
+ content case. Since it is optional to place hash algorithms in the
+ SignedData.digestAlgorithms field, the content will be completely
+ parsed before the set of hash algorithms used in the various
+ SignerInfo structures are determined. It may be that an update to
+ CMS is required to make population of the SignedData.digestAlgorithms
+ field mandatory, in the event that a parameterized hash algorithm is
+ adopted.
+
+ In this document, a new hash function is created that is based on the
+ XOR operator and on MD5. MD5 was deliberately used as the basis of
+ this digest algorithm since it is known to be insecure, and I do not
+ want to make any statements that the hash algorithm designed here is
+ in any way secure. This hash function MUST NOT be released as
+ shipping code, it is designed only for use in experimentation. An
+ example of a parameterized hash algorithm that might be standardized
+ is a scheme developed by Shai Halevi and Hugo Krawczyk [RANDOM-HASH].
+
+1.1. Notation
+
+ The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
+ "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
+ document are to be interpreted as described in [RFC2119].
+
+2. XOR-MD5 Digest Algorithm
+
+ The XOR-MD5 digest algorithm has been designed to use two existing
+ operators, XOR and the MD5 hash algorithm [MD5]. The hash algorithm
+ works as follows:
+
+ 1. A random XOR string consisting of exactly 64 bytes is created.
+
+ 2. The input content is broken up into 64-byte blocks. The last
+ block may be less that 64 bytes.
+
+ 3. Each block is XOR-ed with the random string. The last block uses
+ the same number of bits from the random string as it contains.
+
+ 4. The resulting string is run through the MD5 hash function.
+
+ The length of the XOR string was designed to match the barrel size of
+ the MD5 hash function.
+
+
+
+
+
+
+
+
+
+Schaad Experimental [Page 5]
+
+RFC 6210 CMS Parameterized Hash April 2011
+
+
+3. ASN.1 Encoding
+
+ The following ASN.1 is used to define the algorithm:
+
+ mda-xor-md5-EXPERIMENT DIGEST-ALGORITHM ::= {
+ IDENTIFIER id-alg-MD5-XOR-EXPERIMENT
+ PARAMS TYPE MD5-XOR-EXPERIMENT ARE required
+ }
+
+ id-alg-MD5-XOR-EXPERIMENT OBJECT IDENTIFIER ::= {
+ iso(1) member-body(2) us(840) rsadsi(113549)
+ pkcs(1) pkcs-9(9) smime(16) id-alg(3) 13
+ }
+
+ MD5-XOR-EXPERIMENT ::= OCTET STRING (SIZE(64))
+
+ The octet string holds the value of the random XOR string.
+
+4. CMS ASN.1 Handling
+
+ The algorithm is added to the DigestAlgorithmSet in [CMS].
+
+ When this algorithm is used in a signed message, it is REQUIRED that
+ the algorithm be placed in the SignedData.digestAlgorithms sequence.
+ The algorithm MUST appear in the sequence at least once for each
+ unique set of parameters. The algorithm SHOULD NOT appear multiple
+ times with the same set of parameters.
+
+5. MIME Handling
+
+ This section defines the string that appears in the micalg parameter.
+
+ The algorithm is identified by the string xor-md5. The parameters
+ for the algorithm are the hex-encoded Distinguished Encoding Rules
+ (DER) ASN.1 encoding. The parameters and the identifier string are
+ separated by a colon. One of the issues that needs to be addressed
+ is the fact that this will generate very long data values for
+ parameters. These will be too long for many systems to deal with.
+ The issue of how to deal with this has been addressed in [RFC2231] by
+ creating a method to fragment values. An example content-type string
+ that has been fragmented is:
+
+ Content-Type: multipart/signed;
+ protocol="application/pkcs7-signature";
+ micalg*0="sha1, xor-md5:04400102030405060708090a0b0c0d0e0f0011";
+ micalg*1="12131415161718191a1b1c1d1e1f102122232425262728292a2b";
+ micalg*2="2c2d2e2f203132333435363738";
+ micalg*3="393a3b3c3d3e3f30"; boundary=boundar42
+
+
+
+Schaad Experimental [Page 6]
+
+RFC 6210 CMS Parameterized Hash April 2011
+
+
+ Arguments could be made that the string should be base64 encoded
+ rather than hex encoded. The advantage is that the resulting
+ encoding is shorter. This could be significant if there are a
+ substantial number of parameters and of a substantial size. Even
+ with the above example, it was necessary to break the encoding across
+ multiple lines. The downside would be the requirement that the
+ micalg parameter always be quoted.
+
+ It may be reasonable to require that whitespace be inserted only on
+ encoding boundaries, but it seems to be overly restrictive.
+
+6. IANA Considerations
+
+ All identifiers are assigned out of the S/MIME OID arc.
+
+7. Security Considerations
+
+ The algorithm XOR-MD5 is not designed for general-purpose use. The
+ hash algorithm included here is designed for running this experiment
+ and nothing more.
+
+ This document makes no representation that XOR-MD5 is a secure digest
+ algorithm. I believe that the algorithm is no more secure than MD5,
+ and I consider MD5 to be a broken hash algorithm for many purposes.
+
+ One known issue with the algorithm at present is the fact that the
+ XOR pattern is always 64 bytes long, even if the data is shorter.
+ This means that there is a section of the data than can be
+ manipulated without changing the hash. In a real algorithm, this
+ should either be truncated or forced to a known value.
+
+8. References
+
+8.1. Normative References
+
+ [ASN.1-2008] ITU-T, "ITU-T Recommendations X.680, X.681, X.682, and
+ X.683", 2008.
+
+ [CMS] Housley, R., "Cryptographic Message Syntax (CMS)",
+ RFC 5652, September 2009.
+
+ [MD5] Rivest, R., "The MD5 Message-Digest Algorithm",
+ RFC 1321, April 1992.
+
+ [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
+ Requirement Levels", BCP 14, RFC 2119, March 1997.
+
+
+
+
+
+Schaad Experimental [Page 7]
+
+RFC 6210 CMS Parameterized Hash April 2011
+
+
+ [RFC2231] Freed, N. and K. Moore, "MIME Parameter Value and
+ Encoded Word Extensions: Character Sets, Languages, and
+ Continuations", RFC 2231, November 1997.
+
+ [SMIME-MSG] Ramsdell, B. and S. Turner, "Secure/Multipurpose
+ Internet Mail Extensions (S/MIME) Version 3.2 Message
+ Specification", RFC 5751, January 2010.
+
+8.2. Informative References
+
+ [CMS-ASN] Hoffman, P. and J. Schaad, "New ASN.1 Modules for
+ Cryptographic Message Syntax (CMS) and S/MIME",
+ RFC 5911, June 2010.
+
+ [RANDOM-HASH] Halevi, S. and H. Krawczyk, "Strengthening Digital
+ Signatures via Random Hashing", January 2007,
+ <http://webee.technion.ac.il/~hugo/rhash/rhash.pdf>.
+
+ [RFC5912] Hoffman, P. and J. Schaad, "New ASN.1 Modules for the
+ Public Key Infrastructure Using X.509 (PKIX)",
+ RFC 5912, June 2010.
+
+ [SMIME-EXAMPLES]
+ Hoffman, P., "Examples of S/MIME Messages", RFC 4134,
+ July 2005.
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+Schaad Experimental [Page 8]
+
+RFC 6210 CMS Parameterized Hash April 2011
+
+
+Appendix A. Examples
+
+ Provided here are a set of simple S/MIME messages [SMIME-MSG] that
+ are for testing. The content used is the same as that found in
+ Section 2.1 of [SMIME-EXAMPLES]. The certificates and key pairs
+ found in [SMIME-EXAMPLES] are also used here.
+
+ The Perl script in Appendix A of [SMIME-EXAMPLES] can be used to
+ extract the binary examples from this file. The MIME examples can be
+ extracted with a standard text editor.
+
+ Note: The examples presented here have not been independently
+ verified. I was unable to use the Microsoft APIs because of the new
+ cryptographic hash algorithm. However, for the purposes of this
+ experiment, I believe that the form of the messages, which can be
+ verified visually as correct, is more important than the question of
+ the message validating.
+
+A.1. Encapsulated Signed Data Example
+
+ This section contains a detached signed data example. The content
+ was hashed with the MD5-XOR algorithm defined in this document. The
+ signature is performed using RSA with MD5. The signature is wrapped
+ as an embedded signed mime message.
+
+ MIME-Version: 1.0
+ To: BobRSA@example.com
+ From: AliceDss@example.com
+ Subject: MD5-XOR example message
+ Message-Id: <34567809323489fd.esc@example.com>
+ Date: Wed, 16 Dec 2010 23:13:00 -0500
+ Content-Type: application/pkcs7-mime; smime-type=signed-data;
+ name=smime.p7m;
+ micalg*0="xor-md5: 0440010203405060708090a0b0c0d0e0f10";
+ micalg*1="111213415161718191a1b1c1d1e1f20212223425262728292a2b2c";
+ micalg*2="2d2e2f30313233435363738393a3b3c3d3e3f40"
+ Content-Transfer-Encoding: base64
+ Content-Disposition: attachment; filename=smime.p7m
+
+ MIIEqAYJKoZIhvcNAQcCoIIEmTCCBJUCAQExUTBPBgsqhkiG9w0BCRADDQRAAQIDBAUGBw
+ gJCgsMDQ4PEBESEwQVFhcYGRobHB0eHyAhIiMEJSYnKCkqKywtLi8wMTIzBDU2Nzg5Ojs8
+ PT4/QDArBgkqhkiG9w0BBwGgHgQcVGhpcyBpcyBzb21lIHNhbXBsZSBjb250ZW50LqCCAi
+ swggInMIIBkKADAgECAhBGNGvHgABWvBHTbi7NXXHQMA0GCSqGSIb3DQEBBQUAMBIxEDAO
+ BgNVBAMTB0NhcmxSU0EwHhcNOTkwOTE5MDEwOTAyWhcNMzkxMjMxMjM1OTU5WjARMQ8wDQ
+ YDVQQDEwZCb2JSU0EwgZ8wDQYJKoZIhvcNAQEBBQADgY0AMIGJAoGBAKnhZ5g/OdVf8qCT
+ QV6meYmFyDVdmpFb+x0B2hlwJhcPvaUi0DWFbXqYZhRBXM+3twg7CcmRuBlpN235ZR572a
+ kzJKN/O7uvRgGGNjQyywcDWVL8hYsxBLjMGAgUSOZPHPtdYMTgXB9T039T2GkB8QX4enDR
+ voPGXzjPHCyqaqfrAgMBAAGjfzB9MAwGA1UdEwEB/wQCMAAwDgYDVR0PAQH/BAQDAgUgMB
+
+
+
+Schaad Experimental [Page 9]
+
+RFC 6210 CMS Parameterized Hash April 2011
+
+
+ 8GA1UdIwQYMBaAFOngkCeseCB6mtNM8kI3TiKunji7MB0GA1UdDgQWBBTo9Lhn2LOWpCrz
+ Eaop05Vahha0JDAdBgNVHREEFjAUgRJCb2JSU0FAZXhhbXBsZS5jb20wDQYJKoZIhvcNAQ
+ EFBQADgYEAe45mxfEQPxAgTIhxq3tAayEz+kqV3p0OW2uUIQXA8uF+Ks2ck4iH+4u3fn1B
+ YeHk1m354gRVYUW8ZCdEwKG9WXnZHWQ8IdZFsF1oM5LqrPFX5YF9mOY1kaM53nf06Bw7Kd
+ x/UQeX8zbwUArdm962XjgRK/tX6oltrcmI2I/PK9MxggHfMIIB2wIBATAmMBIxEDAOBgNV
+ BAMTB0NhcmxSU0ECEEY0a8eAAFa8EdNuLs1dcdAwTwYLKoZIhvcNAQkQAw0EQAECAwQFBg
+ cICQoLDA0ODxAREhMEFRYXGBkaGxwdHh8gISIjBCUmJygpKissLS4vMDEyMwQ1Njc4OTo7
+ PD0+P0CggcowGAYJKoZIhvcNAQkDMQsGCSqGSIb3DQEHATAcBgkqhkiG9w0BCQUxDxcNMD
+ kxMjEwMjMyNTAwWjAfBgkqhkiG9w0BCQQxEgQQlmmuYRtXnoPqECtrSd3A+TBvBgkqhkiG
+ 9w0BCTQxYjBgME8GCyqGSIb3DQEJEAMNBEABAgMEBQYHCAkKCwwNDg8QERITBBUWFxgZGh
+ scHR4fICEiIwQlJicoKSorLC0uLzAxMjMENTY3ODk6Ozw9Pj9AoQ0GCSqGSIb3DQEBBAUA
+ MA0GCSqGSIb3DQEBBAUABIGAClMpfG4IL1yAdRxWdvYKbtuFz1XKnFqo9ui7V5PndjlDut
+ yib02knY7UtGNhg6oVEkiZHxYh/iLuoLOHSFA1P4ZacTYrEKChF4K18dsqvlFip1vn8BG/
+ ysFUDfbx5VcTG2Md0/NHV+qj5ihqM+Pye6Urp+5jbqVgpZOXSLfP+pI=
+
+ |>sd.bin
+ |MIIEqAYJKoZIhvcNAQcCoIIEmTCCBJUCAQExUTBPBgsqhkiG9w0BCRADDQRAAQIDBAUGBw
+ |gJCgsMDQ4PEBESEwQVFhcYGRobHB0eHyAhIiMEJSYnKCkqKywtLi8wMTIzBDU2Nzg5Ojs8
+ |PT4/QDArBgkqhkiG9w0BBwGgHgQcVGhpcyBpcyBzb21lIHNhbXBsZSBjb250ZW50LqCCAi
+ |swggInMIIBkKADAgECAhBGNGvHgABWvBHTbi7NXXHQMA0GCSqGSIb3DQEBBQUAMBIxEDAO
+ |BgNVBAMTB0NhcmxSU0EwHhcNOTkwOTE5MDEwOTAyWhcNMzkxMjMxMjM1OTU5WjARMQ8wDQ
+ |YDVQQDEwZCb2JSU0EwgZ8wDQYJKoZIhvcNAQEBBQADgY0AMIGJAoGBAKnhZ5g/OdVf8qCT
+ |QV6meYmFyDVdmpFb+x0B2hlwJhcPvaUi0DWFbXqYZhRBXM+3twg7CcmRuBlpN235ZR572a
+ |kzJKN/O7uvRgGGNjQyywcDWVL8hYsxBLjMGAgUSOZPHPtdYMTgXB9T039T2GkB8QX4enDR
+ |voPGXzjPHCyqaqfrAgMBAAGjfzB9MAwGA1UdEwEB/wQCMAAwDgYDVR0PAQH/BAQDAgUgMB
+ |8GA1UdIwQYMBaAFOngkCeseCB6mtNM8kI3TiKunji7MB0GA1UdDgQWBBTo9Lhn2LOWpCrz
+ |Eaop05Vahha0JDAdBgNVHREEFjAUgRJCb2JSU0FAZXhhbXBsZS5jb20wDQYJKoZIhvcNAQ
+ |EFBQADgYEAe45mxfEQPxAgTIhxq3tAayEz+kqV3p0OW2uUIQXA8uF+Ks2ck4iH+4u3fn1B
+ |YeHk1m354gRVYUW8ZCdEwKG9WXnZHWQ8IdZFsF1oM5LqrPFX5YF9mOY1kaM53nf06Bw7Kd
+ |x/UQeX8zbwUArdm962XjgRK/tX6oltrcmI2I/PK9MxggHfMIIB2wIBATAmMBIxEDAOBgNV
+ |BAMTB0NhcmxSU0ECEEY0a8eAAFa8EdNuLs1dcdAwTwYLKoZIhvcNAQkQAw0EQAECAwQFBg
+ |cICQoLDA0ODxAREhMEFRYXGBkaGxwdHh8gISIjBCUmJygpKissLS4vMDEyMwQ1Njc4OTo7
+ |PD0+P0CggcowGAYJKoZIhvcNAQkDMQsGCSqGSIb3DQEHATAcBgkqhkiG9w0BCQUxDxcNMD
+ |kxMjEwMjMyNTAwWjAfBgkqhkiG9w0BCQQxEgQQlmmuYRtXnoPqECtrSd3A+TBvBgkqhkiG
+ |9w0BCTQxYjBgME8GCyqGSIb3DQEJEAMNBEABAgMEBQYHCAkKCwwNDg8QERITBBUWFxgZGh
+ |scHR4fICEiIwQlJicoKSorLC0uLzAxMjMENTY3ODk6Ozw9Pj9AoQ0GCSqGSIb3DQEBBAUA
+ |MA0GCSqGSIb3DQEBBAUABIGAClMpfG4IL1yAdRxWdvYKbtuFz1XKnFqo9ui7V5PndjlDut
+ |yib02knY7UtGNhg6oVEkiZHxYh/iLuoLOHSFA1P4ZacTYrEKChF4K18dsqvlFip1vn8BG/
+ |ysFUDfbx5VcTG2Md0/NHV+qj5ihqM+Pye6Urp+5jbqVgpZOXSLfP+pI=
+ |<sd.bin
+
+A.2. Multipart Signed Message
+
+ This section contains a detached signed data example. The content
+ was hashed with the MD5-XOR algorithm defined in this document. The
+ signature is performed using RSA with MD5. The signature is wrapped
+ as a detached signed mime message.
+
+
+
+
+Schaad Experimental [Page 10]
+
+RFC 6210 CMS Parameterized Hash April 2011
+
+
+MIME-Version: 1.0
+To: User2@example.com
+From: BobRSA@example.com
+Subject: MD5-XOR signing example
+Message-Id: <091218002550300.249@example.com>
+Date: Fri, 18 Dec 2010 00:25:21 -0300
+Content-Type: multipart/signed;
+ micalg*0="xor-md5: 0440010203405060708090a0b0c0d0e0f10";
+ micalg*1="111213415161718191a1b1c1d1e1f20212223425262728292a2b2c2d2e";
+ micalg*2="2f30313233435363738393a3b3c3d3e3f40";
+ boundary="----=_NextBoundry____Fri,_18_Dec_2009_00:25:21";
+ protocol="application/pkcs7-signature"
+
+This is a multi-part message in MIME format.
+
+------=_NextBoundry____Fri,_18_Dec_2009_00:25:21
+
+This is some sample content.
+------=_NextBoundry____Fri,_18_Dec_2009_00:25:21
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+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+
+------=_NextBoundry____Fri,_18_Dec_2009_00:25:21--
+
+
+
+Schaad Experimental [Page 11]
+
+RFC 6210 CMS Parameterized Hash April 2011
+
+
+A.3. Authenticated Data Example
+
+ This section contains an authenticated data example. The content was
+ hashed with the MD5-XOR algorithm defined in this document. The
+ authentication was done with the HMAC-SHA1 algorithm. The key is
+ transported using RSA encryption to BobRSASignByCarl certificate.
+
+MIME-Version: 1.0
+To: BobRSA@example.com
+From: AliceDss@example.com
+Subject: MD5-XOR example message
+Message-Id: <34567809323489fd.esc@example.com>
+Date: Wed, 16 Dec 2010 23:13:00 -0500
+Content-Type: application/pkcs7-mime; smime-type=authenticated-data;
+ name=smime.p7m;
+ micalg*0="xor-md5: 0440010203405060708090a0b0c0d0e0f10";
+ micalg*1="111213415161718191a1b1c1d1e1f20212223425262728292a2b2c2d2e";
+ micalg*2="2f30313233435363738393a3b3c3d3e3f40"
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+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+
+|>ad.bin
+|MIICRQYLKoZIhvcNAQkQAQKgggI0MIICMAIBADGBwDCBvQIBADAmMBIxEDAOBgNVBAMMB0
+|NhcmxSU0ECEEY0a8eAAFa8EdNuLs1dcdAwDQYJKoZIhvcNAQEBBQAEgYCH70EpEikY7deb
+|859YJRAWfFondQv1D4NFltw6C1ceheWnlAU0C2WEXr3LUBXZp1/PSte29FnJxu5bXCTn1g
+|elMm6zNlZNWNd0KadVBcaxi1n8L52tVM5sWFGJPO5cStOyAka2ucuZM6iAnCSkn1Ju7fgU
+|5j2g3bZ/IM8nHTcygjAKBggrBgEFBQgBAqFPBgsqhkiG9w0BCRADDQRAAQIDBAUGBwgJCg
+|sMDQ4PEBESEwQVFhcYGRobHB0eHyAhIiMEJSYnKCkqKywtLi8wMTIzBDU2Nzg5Ojs8PT4/
+|QDArBgkqhkiG9w0BBwGgHgQcVGhpcyBpcyBzb21lIHNhbXBsZSBjb250ZW50LqKBxzAYBg
+|kqhkiG9w0BCQMxCwYJKoZIhvcNAQcBMBwGCSqGSIb3DQEJBTEPFw0wOTEyMTAyMzI1MDBa
+|MB8GCSqGSIb3DQEJBDESBBCWaa5hG1eeg+oQK2tJ3cD5MGwGCSqGSIb3DQEJNDFfMF0wTw
+|YLKoZIhvcNAQkQAw0EQAECAwQFBgcICQoLDA0ODxAREhMEFRYXGBkaGxwdHh8gISIjBCUm
+|JygpKissLS4vMDEyMwQ1Njc4OTo7PD0+P0CiCgYIKwYBBQUIAQIEFLjUxQ9PJFzFnWraxb
+|EIbVbg2xql
+|<ad.bin
+
+
+
+Schaad Experimental [Page 12]
+
+RFC 6210 CMS Parameterized Hash April 2011
+
+
+Appendix B. 2008 ASN.1 Module
+
+ The ASN.1 module defined uses the 2008 ASN.1 definitions found in
+ [ASN.1-2008]. This module contains the ASN.1 module that contains
+ the required definitions for the types and values defined in this
+ document. The module uses the class defined in [CMS-ASN] and
+ [RFC5912].
+
+ MD5-HASH-EXPERIMENT
+ { iso(1) member-body(2) us(840) rsadsi(113549)
+ pkcs(1) pkcs-9(9) smime(16) modules(0)
+ id-mod-MD5-XOR-EXPERIMENT(999) }
+ DEFINITIONS IMPLICIT TAGS ::=
+ BEGIN
+ IMPORTS
+
+ -- Cryptographic Message Syntax (CMS) [CMS]
+
+ DigestAlgorithmIdentifier, MessageAuthenticationCodeAlgorithm,
+ SignatureAlgorithmIdentifier, DIGEST-ALGORITHM
+ FROM CryptographicMessageSyntax-2009
+ { iso(1) member-body(2) us(840) rsadsi(113549)
+ pkcs(1) pkcs-9(9) smime(16) modules(0) id-mod-cms-2004-02(41) }
+
+ -- Common PKIX structures [RFC5912]
+
+ ATTRIBUTE
+ FROM PKIX-CommonTypes-2009
+ { iso(1) identified-organization(3) dod(6) internet(1)
+ security(5) mechanisms(5) pkix(7) id-mod(0)
+ id-mod-pkixCommon-02(57)};
+
+ mda-xor-md5-EXPERIMENT DIGEST-ALGORITHM ::= {
+ IDENTIFIER id-alg-MD5-XOR-EXPERIMENT
+ PARAMS TYPE MD5-XOR-EXPERIMENT ARE required
+ }
+
+ id-alg-MD5-XOR-EXPERIMENT OBJECT IDENTIFIER ::= {
+ iso(1) member-body(2) us(840) rsadsi(113549)
+ pkcs(1) pkcs-9(9) smime(16) id-alg(3) 13
+ }
+
+ MD5-XOR-EXPERIMENT ::= OCTET STRING (SIZE(64))
+
+ END
+
+
+
+
+
+
+Schaad Experimental [Page 13]
+
+RFC 6210 CMS Parameterized Hash April 2011
+
+
+Author's Address
+
+ Jim Schaad
+ Soaring Hawk Consulting
+
+ EMail: ietf@augustcellars.com
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+Schaad Experimental [Page 14]
+