diff options
| -rw-r--r-- | main.c | 26 |
1 files changed, 20 insertions, 6 deletions
@@ -186,19 +186,31 @@ bool totp(struct totp_config conf, uint32_t *code) { int off; + bool clean; uint8_t *key; + char *enc_sec; uchar *mac; time_t epoch; - size_t keylen; + size_t keylen, enc_sec_len, old; uint8_t buf[sizeof(time_t)]; /* Enough for a 64bit num */ uint32_t binc; - /* TODO: conf.enc_sec needs to be ‘=’ padded to a multiple of 8 */ + /* conf.enc_sec needs to be ‘=’ padded to a multiple of 8 */ + old = enc_sec_len = strlen(conf.enc_sec); + if (enc_sec_len % 8 == 0) { + enc_sec = (char *)conf.enc_sec; + clean = false; + } else { + enc_sec_len += 8 - enc_sec_len % 8; + enc_sec = malloc(enc_sec_len); + memcpy(enc_sec, conf.enc_sec, old); + memset(enc_sec + old, '=', enc_sec_len - old); + clean = true; + } - /* When decoding base32, you need ceil(conf.enc_sec / 1.6) bytes */ - keylen = strlen(conf.enc_sec) / 1.6 + 1; + keylen = old * 5 / 8; key = calloc(keylen, sizeof(char)); - b32toa(key, conf.enc_sec, strlen(conf.enc_sec)); + b32toa(key, enc_sec, enc_sec_len); if (time(&epoch) == (time_t)-1) { warn("time"); @@ -215,7 +227,7 @@ totp(struct totp_config conf, uint32_t *code) buf[5] = (epoch >> 16) & 0xFF; buf[6] = (epoch >> 8) & 0xFF; buf[7] = (epoch >> 0) & 0xFF; - + mac = HMAC(EVP_sha1(), key, keylen, buf, sizeof(buf), NULL, NULL); if (mac == NULL) WARNX_AND_RET("Failed to compute HMAC SHA-1 hash"); @@ -228,6 +240,8 @@ totp(struct totp_config conf, uint32_t *code) | (mac[off + 3] & 0xFF) << 0; *code = binc % pow32(10, conf.len); + if (clean) + free(enc_sec); free(key); return true; } |