| /* $Id$ */ |
| /* |
| * Copyright (C) 2008-2011 Teluu Inc. (http://www.teluu.com) |
| * Copyright (C) 2003-2008 Benny Prijono <benny@prijono.org> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| #include <pjnath/stun_auth.h> |
| #include <pjnath/errno.h> |
| #include <pjlib-util/hmac_sha1.h> |
| #include <pjlib-util/md5.h> |
| #include <pjlib-util/sha1.h> |
| #include <pj/assert.h> |
| #include <pj/log.h> |
| #include <pj/pool.h> |
| #include <pj/string.h> |
| |
| #define THIS_FILE "stun_auth.c" |
| |
| /* Duplicate credential */ |
| PJ_DEF(void) pj_stun_auth_cred_dup( pj_pool_t *pool, |
| pj_stun_auth_cred *dst, |
| const pj_stun_auth_cred *src) |
| { |
| dst->type = src->type; |
| |
| switch (src->type) { |
| case PJ_STUN_AUTH_CRED_STATIC: |
| pj_strdup(pool, &dst->data.static_cred.realm, |
| &src->data.static_cred.realm); |
| pj_strdup(pool, &dst->data.static_cred.username, |
| &src->data.static_cred.username); |
| dst->data.static_cred.data_type = src->data.static_cred.data_type; |
| pj_strdup(pool, &dst->data.static_cred.data, |
| &src->data.static_cred.data); |
| pj_strdup(pool, &dst->data.static_cred.nonce, |
| &src->data.static_cred.nonce); |
| break; |
| case PJ_STUN_AUTH_CRED_DYNAMIC: |
| pj_memcpy(&dst->data.dyn_cred, &src->data.dyn_cred, |
| sizeof(src->data.dyn_cred)); |
| break; |
| } |
| } |
| |
| |
| /* |
| * Duplicate request credential. |
| */ |
| PJ_DEF(void) pj_stun_req_cred_info_dup( pj_pool_t *pool, |
| pj_stun_req_cred_info *dst, |
| const pj_stun_req_cred_info *src) |
| { |
| pj_strdup(pool, &dst->realm, &src->realm); |
| pj_strdup(pool, &dst->username, &src->username); |
| pj_strdup(pool, &dst->nonce, &src->nonce); |
| pj_strdup(pool, &dst->auth_key, &src->auth_key); |
| } |
| |
| |
| /* Calculate HMAC-SHA1 key for long term credential, by getting |
| * MD5 digest of username, realm, and password. |
| */ |
| static void calc_md5_key(pj_uint8_t digest[16], |
| const pj_str_t *realm, |
| const pj_str_t *username, |
| const pj_str_t *passwd) |
| { |
| /* The 16-byte key for MESSAGE-INTEGRITY HMAC is formed by taking |
| * the MD5 hash of the result of concatenating the following five |
| * fields: (1) The username, with any quotes and trailing nulls |
| * removed, (2) A single colon, (3) The realm, with any quotes and |
| * trailing nulls removed, (4) A single colon, and (5) The |
| * password, with any trailing nulls removed. |
| */ |
| pj_md5_context ctx; |
| pj_str_t s; |
| |
| pj_md5_init(&ctx); |
| |
| #define REMOVE_QUOTE(s) if (s.slen && *s.ptr=='"') \ |
| s.ptr++, s.slen--; \ |
| if (s.slen && s.ptr[s.slen-1]=='"') \ |
| s.slen--; |
| |
| /* Add username */ |
| s = *username; |
| REMOVE_QUOTE(s); |
| pj_md5_update(&ctx, (pj_uint8_t*)s.ptr, (unsigned)s.slen); |
| |
| /* Add single colon */ |
| pj_md5_update(&ctx, (pj_uint8_t*)":", 1); |
| |
| /* Add realm */ |
| s = *realm; |
| REMOVE_QUOTE(s); |
| pj_md5_update(&ctx, (pj_uint8_t*)s.ptr, (unsigned)s.slen); |
| |
| #undef REMOVE_QUOTE |
| |
| /* Another colon */ |
| pj_md5_update(&ctx, (pj_uint8_t*)":", 1); |
| |
| /* Add password */ |
| pj_md5_update(&ctx, (pj_uint8_t*)passwd->ptr, (unsigned)passwd->slen); |
| |
| /* Done */ |
| pj_md5_final(&ctx, digest); |
| } |
| |
| |
| /* |
| * Create authentication key to be used for encoding the message with |
| * MESSAGE-INTEGRITY. |
| */ |
| PJ_DEF(void) pj_stun_create_key(pj_pool_t *pool, |
| pj_str_t *key, |
| const pj_str_t *realm, |
| const pj_str_t *username, |
| pj_stun_passwd_type data_type, |
| const pj_str_t *data) |
| { |
| PJ_ASSERT_ON_FAIL(pool && key && username && data, return); |
| |
| if (realm && realm->slen) { |
| if (data_type == PJ_STUN_PASSWD_PLAIN) { |
| key->ptr = (char*) pj_pool_alloc(pool, 16); |
| calc_md5_key((pj_uint8_t*)key->ptr, realm, username, data); |
| key->slen = 16; |
| } else { |
| pj_strdup(pool, key, data); |
| } |
| } else { |
| pj_assert(data_type == PJ_STUN_PASSWD_PLAIN); |
| pj_strdup(pool, key, data); |
| } |
| } |
| |
| |
| PJ_INLINE(pj_uint16_t) GET_VAL16(const pj_uint8_t *pdu, unsigned pos) |
| { |
| return (pj_uint16_t) ((pdu[pos] << 8) + pdu[pos+1]); |
| } |
| |
| |
| PJ_INLINE(void) PUT_VAL16(pj_uint8_t *buf, unsigned pos, pj_uint16_t hval) |
| { |
| buf[pos+0] = (pj_uint8_t) ((hval & 0xFF00) >> 8); |
| buf[pos+1] = (pj_uint8_t) ((hval & 0x00FF) >> 0); |
| } |
| |
| |
| /* Send 401 response */ |
| static pj_status_t create_challenge(pj_pool_t *pool, |
| const pj_stun_msg *msg, |
| int err_code, |
| const char *errstr, |
| const pj_str_t *realm, |
| const pj_str_t *nonce, |
| pj_stun_msg **p_response) |
| { |
| pj_stun_msg *response; |
| pj_str_t tmp_nonce; |
| pj_str_t err_msg; |
| pj_status_t rc; |
| |
| rc = pj_stun_msg_create_response(pool, msg, err_code, |
| (errstr?pj_cstr(&err_msg, errstr):NULL), |
| &response); |
| if (rc != PJ_SUCCESS) |
| return rc; |
| |
| /* SHOULD NOT add REALM, NONCE, USERNAME, and M-I on 400 response */ |
| if (err_code!=400 && realm && realm->slen) { |
| rc = pj_stun_msg_add_string_attr(pool, response, |
| PJ_STUN_ATTR_REALM, |
| realm); |
| if (rc != PJ_SUCCESS) |
| return rc; |
| |
| /* long term must include nonce */ |
| if (!nonce || nonce->slen == 0) { |
| tmp_nonce = pj_str("pjstun"); |
| nonce = &tmp_nonce; |
| } |
| } |
| |
| if (err_code!=400 && nonce && nonce->slen) { |
| rc = pj_stun_msg_add_string_attr(pool, response, |
| PJ_STUN_ATTR_NONCE, |
| nonce); |
| if (rc != PJ_SUCCESS) |
| return rc; |
| } |
| |
| *p_response = response; |
| |
| return PJ_SUCCESS; |
| } |
| |
| |
| /* Verify credential in the request */ |
| PJ_DEF(pj_status_t) pj_stun_authenticate_request(const pj_uint8_t *pkt, |
| unsigned pkt_len, |
| const pj_stun_msg *msg, |
| pj_stun_auth_cred *cred, |
| pj_pool_t *pool, |
| pj_stun_req_cred_info *p_info, |
| pj_stun_msg **p_response) |
| { |
| pj_stun_req_cred_info tmp_info; |
| const pj_stun_msgint_attr *amsgi; |
| unsigned i, amsgi_pos; |
| pj_bool_t has_attr_beyond_mi; |
| const pj_stun_username_attr *auser; |
| const pj_stun_realm_attr *arealm; |
| const pj_stun_realm_attr *anonce; |
| pj_hmac_sha1_context ctx; |
| pj_uint8_t digest[PJ_SHA1_DIGEST_SIZE]; |
| pj_stun_status err_code; |
| const char *err_text = NULL; |
| pj_status_t status; |
| |
| /* msg and credential MUST be specified */ |
| PJ_ASSERT_RETURN(pkt && pkt_len && msg && cred, PJ_EINVAL); |
| |
| /* If p_response is specified, pool MUST be specified. */ |
| PJ_ASSERT_RETURN(!p_response || pool, PJ_EINVAL); |
| |
| if (p_response) |
| *p_response = NULL; |
| |
| if (!PJ_STUN_IS_REQUEST(msg->hdr.type)) |
| p_response = NULL; |
| |
| if (p_info == NULL) |
| p_info = &tmp_info; |
| |
| pj_bzero(p_info, sizeof(pj_stun_req_cred_info)); |
| |
| /* Get realm and nonce from credential */ |
| p_info->realm.slen = p_info->nonce.slen = 0; |
| if (cred->type == PJ_STUN_AUTH_CRED_STATIC) { |
| p_info->realm = cred->data.static_cred.realm; |
| p_info->nonce = cred->data.static_cred.nonce; |
| } else if (cred->type == PJ_STUN_AUTH_CRED_DYNAMIC) { |
| status = cred->data.dyn_cred.get_auth(cred->data.dyn_cred.user_data, |
| pool, &p_info->realm, |
| &p_info->nonce); |
| if (status != PJ_SUCCESS) |
| return status; |
| } else { |
| pj_assert(!"Invalid credential type"); |
| return PJ_EBUG; |
| } |
| |
| /* Look for MESSAGE-INTEGRITY while counting the position */ |
| amsgi_pos = 0; |
| has_attr_beyond_mi = PJ_FALSE; |
| amsgi = NULL; |
| for (i=0; i<msg->attr_count; ++i) { |
| if (msg->attr[i]->type == PJ_STUN_ATTR_MESSAGE_INTEGRITY) { |
| amsgi = (const pj_stun_msgint_attr*) msg->attr[i]; |
| } else if (amsgi) { |
| has_attr_beyond_mi = PJ_TRUE; |
| break; |
| } else { |
| amsgi_pos += ((msg->attr[i]->length+3) & ~0x03) + 4; |
| } |
| } |
| |
| if (amsgi == NULL) { |
| /* According to rfc3489bis-10 Sec 10.1.2/10.2.2, we should return 400 |
| for short term, and 401 for long term. |
| The rule has been changed from rfc3489bis-06 |
| */ |
| err_code = p_info->realm.slen ? PJ_STUN_SC_UNAUTHORIZED : |
| PJ_STUN_SC_BAD_REQUEST; |
| goto on_auth_failed; |
| } |
| |
| /* Next check that USERNAME is present */ |
| auser = (const pj_stun_username_attr*) |
| pj_stun_msg_find_attr(msg, PJ_STUN_ATTR_USERNAME, 0); |
| if (auser == NULL) { |
| /* According to rfc3489bis-10 Sec 10.1.2/10.2.2, we should return 400 |
| for both short and long term, since M-I is present. |
| The rule has been changed from rfc3489bis-06 |
| */ |
| err_code = PJ_STUN_SC_BAD_REQUEST; |
| err_text = "Missing USERNAME"; |
| goto on_auth_failed; |
| } |
| |
| /* Get REALM, if any */ |
| arealm = (const pj_stun_realm_attr*) |
| pj_stun_msg_find_attr(msg, PJ_STUN_ATTR_REALM, 0); |
| |
| /* Reject with 400 if we have long term credential and the request |
| * is missing REALM attribute. |
| */ |
| if (p_info->realm.slen && arealm==NULL) { |
| err_code = PJ_STUN_SC_BAD_REQUEST; |
| err_text = "Missing REALM"; |
| goto on_auth_failed; |
| } |
| |
| /* Check if username match */ |
| if (cred->type == PJ_STUN_AUTH_CRED_STATIC) { |
| pj_bool_t username_ok; |
| username_ok = !pj_strcmp(&auser->value, |
| &cred->data.static_cred.username); |
| if (username_ok) { |
| pj_strdup(pool, &p_info->username, |
| &cred->data.static_cred.username); |
| pj_stun_create_key(pool, &p_info->auth_key, &p_info->realm, |
| &auser->value, cred->data.static_cred.data_type, |
| &cred->data.static_cred.data); |
| } else { |
| /* Username mismatch */ |
| /* According to rfc3489bis-10 Sec 10.1.2/10.2.2, we should |
| * return 401 |
| */ |
| err_code = PJ_STUN_SC_UNAUTHORIZED; |
| goto on_auth_failed; |
| } |
| } else if (cred->type == PJ_STUN_AUTH_CRED_DYNAMIC) { |
| pj_stun_passwd_type data_type = PJ_STUN_PASSWD_PLAIN; |
| pj_str_t password; |
| pj_status_t rc; |
| |
| rc = cred->data.dyn_cred.get_password(msg, |
| cred->data.dyn_cred.user_data, |
| (arealm?&arealm->value:NULL), |
| &auser->value, pool, |
| &data_type, &password); |
| if (rc == PJ_SUCCESS) { |
| pj_strdup(pool, &p_info->username, &auser->value); |
| pj_stun_create_key(pool, &p_info->auth_key, |
| (arealm?&arealm->value:NULL), &auser->value, |
| data_type, &password); |
| } else { |
| err_code = PJ_STUN_SC_UNAUTHORIZED; |
| goto on_auth_failed; |
| } |
| } else { |
| pj_assert(!"Invalid credential type"); |
| return PJ_EBUG; |
| } |
| |
| |
| |
| /* Get NONCE attribute */ |
| anonce = (pj_stun_nonce_attr*) |
| pj_stun_msg_find_attr(msg, PJ_STUN_ATTR_NONCE, 0); |
| |
| /* Check for long term/short term requirements. */ |
| if (p_info->realm.slen != 0 && arealm == NULL) { |
| /* Long term credential is required and REALM is not present */ |
| err_code = PJ_STUN_SC_BAD_REQUEST; |
| err_text = "Missing REALM"; |
| goto on_auth_failed; |
| |
| } else if (p_info->realm.slen != 0 && arealm != NULL) { |
| /* We want long term, and REALM is present */ |
| |
| /* NONCE must be present. */ |
| if (anonce == NULL && p_info->nonce.slen) { |
| err_code = PJ_STUN_SC_BAD_REQUEST; |
| err_text = "Missing NONCE"; |
| goto on_auth_failed; |
| } |
| |
| /* Verify REALM matches */ |
| if (pj_stricmp(&arealm->value, &p_info->realm)) { |
| /* REALM doesn't match */ |
| err_code = PJ_STUN_SC_UNAUTHORIZED; |
| err_text = "Invalid REALM"; |
| goto on_auth_failed; |
| } |
| |
| /* Valid case, will validate the message integrity later */ |
| |
| } else if (p_info->realm.slen == 0 && arealm != NULL) { |
| /* We want to use short term credential, but client uses long |
| * term credential. The draft doesn't mention anything about |
| * switching between long term and short term. |
| */ |
| |
| /* For now just accept the credential, anyway it will probably |
| * cause wrong message integrity value later. |
| */ |
| } else if (p_info->realm.slen==0 && arealm == NULL) { |
| /* Short term authentication is wanted, and one is supplied */ |
| |
| /* Application MAY request NONCE to be supplied */ |
| if (p_info->nonce.slen != 0) { |
| err_code = PJ_STUN_SC_UNAUTHORIZED; |
| err_text = "NONCE required"; |
| goto on_auth_failed; |
| } |
| } |
| |
| /* If NONCE is present, validate it */ |
| if (anonce) { |
| pj_bool_t ok; |
| |
| if (cred->type == PJ_STUN_AUTH_CRED_DYNAMIC && |
| cred->data.dyn_cred.verify_nonce != NULL) |
| { |
| ok=cred->data.dyn_cred.verify_nonce(msg, |
| cred->data.dyn_cred.user_data, |
| (arealm?&arealm->value:NULL), |
| &auser->value, |
| &anonce->value); |
| } else if (cred->type == PJ_STUN_AUTH_CRED_DYNAMIC) { |
| ok = PJ_TRUE; |
| } else { |
| if (p_info->nonce.slen) { |
| ok = !pj_strcmp(&anonce->value, &p_info->nonce); |
| } else { |
| ok = PJ_TRUE; |
| } |
| } |
| |
| if (!ok) { |
| err_code = PJ_STUN_SC_STALE_NONCE; |
| goto on_auth_failed; |
| } |
| } |
| |
| /* Now calculate HMAC of the message. */ |
| pj_hmac_sha1_init(&ctx, (pj_uint8_t*)p_info->auth_key.ptr, |
| (unsigned)p_info->auth_key.slen); |
| |
| #if PJ_STUN_OLD_STYLE_MI_FINGERPRINT |
| /* Pre rfc3489bis-06 style of calculation */ |
| pj_hmac_sha1_update(&ctx, pkt, 20); |
| #else |
| /* First calculate HMAC for the header. |
| * The calculation is different depending on whether FINGERPRINT attribute |
| * is present in the message. |
| */ |
| if (has_attr_beyond_mi) { |
| pj_uint8_t hdr_copy[20]; |
| pj_memcpy(hdr_copy, pkt, 20); |
| PUT_VAL16(hdr_copy, 2, (pj_uint16_t)(amsgi_pos + 24)); |
| pj_hmac_sha1_update(&ctx, hdr_copy, 20); |
| } else { |
| pj_hmac_sha1_update(&ctx, pkt, 20); |
| } |
| #endif /* PJ_STUN_OLD_STYLE_MI_FINGERPRINT */ |
| |
| /* Now update with the message body */ |
| pj_hmac_sha1_update(&ctx, pkt+20, amsgi_pos); |
| #if PJ_STUN_OLD_STYLE_MI_FINGERPRINT |
| // This is no longer necessary as per rfc3489bis-08 |
| if ((amsgi_pos+20) & 0x3F) { |
| pj_uint8_t zeroes[64]; |
| pj_bzero(zeroes, sizeof(zeroes)); |
| pj_hmac_sha1_update(&ctx, zeroes, 64-((amsgi_pos+20) & 0x3F)); |
| } |
| #endif |
| pj_hmac_sha1_final(&ctx, digest); |
| |
| |
| /* Compare HMACs */ |
| if (pj_memcmp(amsgi->hmac, digest, 20)) { |
| /* HMAC value mismatch */ |
| /* According to rfc3489bis-10 Sec 10.1.2 we should return 401 */ |
| err_code = PJ_STUN_SC_UNAUTHORIZED; |
| err_text = "MESSAGE-INTEGRITY mismatch"; |
| goto on_auth_failed; |
| } |
| |
| /* Everything looks okay! */ |
| return PJ_SUCCESS; |
| |
| on_auth_failed: |
| if (p_response) { |
| create_challenge(pool, msg, err_code, err_text, |
| &p_info->realm, &p_info->nonce, p_response); |
| } |
| return PJ_STATUS_FROM_STUN_CODE(err_code); |
| } |
| |
| |
| /* Determine if STUN message can be authenticated */ |
| PJ_DEF(pj_bool_t) pj_stun_auth_valid_for_msg(const pj_stun_msg *msg) |
| { |
| unsigned msg_type = msg->hdr.type; |
| const pj_stun_errcode_attr *err_attr; |
| |
| /* STUN requests and success response can be authenticated */ |
| if (!PJ_STUN_IS_ERROR_RESPONSE(msg_type) && |
| !PJ_STUN_IS_INDICATION(msg_type)) |
| { |
| return PJ_TRUE; |
| } |
| |
| /* STUN Indication cannot be authenticated */ |
| if (PJ_STUN_IS_INDICATION(msg_type)) |
| return PJ_FALSE; |
| |
| /* Authentication for STUN error responses depend on the error |
| * code. |
| */ |
| err_attr = (const pj_stun_errcode_attr*) |
| pj_stun_msg_find_attr(msg, PJ_STUN_ATTR_ERROR_CODE, 0); |
| if (err_attr == NULL) { |
| PJ_LOG(4,(THIS_FILE, "STUN error code attribute not present in " |
| "error response")); |
| return PJ_TRUE; |
| } |
| |
| switch (err_attr->err_code) { |
| case PJ_STUN_SC_BAD_REQUEST: /* 400 (Bad Request) */ |
| case PJ_STUN_SC_UNAUTHORIZED: /* 401 (Unauthorized) */ |
| case PJ_STUN_SC_STALE_NONCE: /* 438 (Stale Nonce) */ |
| |
| /* Due to the way this response is generated here, we can't really |
| * authenticate 420 (Unknown Attribute) response */ |
| case PJ_STUN_SC_UNKNOWN_ATTRIBUTE: |
| return PJ_FALSE; |
| default: |
| return PJ_TRUE; |
| } |
| } |
| |
| |
| /* Authenticate MESSAGE-INTEGRITY in the response */ |
| PJ_DEF(pj_status_t) pj_stun_authenticate_response(const pj_uint8_t *pkt, |
| unsigned pkt_len, |
| const pj_stun_msg *msg, |
| const pj_str_t *key) |
| { |
| const pj_stun_msgint_attr *amsgi; |
| unsigned i, amsgi_pos; |
| pj_bool_t has_attr_beyond_mi; |
| pj_hmac_sha1_context ctx; |
| pj_uint8_t digest[PJ_SHA1_DIGEST_SIZE]; |
| |
| PJ_ASSERT_RETURN(pkt && pkt_len && msg && key, PJ_EINVAL); |
| |
| /* First check that MESSAGE-INTEGRITY is present */ |
| amsgi = (const pj_stun_msgint_attr*) |
| pj_stun_msg_find_attr(msg, PJ_STUN_ATTR_MESSAGE_INTEGRITY, 0); |
| if (amsgi == NULL) { |
| return PJ_STATUS_FROM_STUN_CODE(PJ_STUN_SC_UNAUTHORIZED); |
| } |
| |
| |
| /* Check that message length is valid */ |
| if (msg->hdr.length < 24) { |
| return PJNATH_EINSTUNMSGLEN; |
| } |
| |
| /* Look for MESSAGE-INTEGRITY while counting the position */ |
| amsgi_pos = 0; |
| has_attr_beyond_mi = PJ_FALSE; |
| amsgi = NULL; |
| for (i=0; i<msg->attr_count; ++i) { |
| if (msg->attr[i]->type == PJ_STUN_ATTR_MESSAGE_INTEGRITY) { |
| amsgi = (const pj_stun_msgint_attr*) msg->attr[i]; |
| } else if (amsgi) { |
| has_attr_beyond_mi = PJ_TRUE; |
| break; |
| } else { |
| amsgi_pos += ((msg->attr[i]->length+3) & ~0x03) + 4; |
| } |
| } |
| |
| if (amsgi == NULL) { |
| return PJ_STATUS_FROM_STUN_CODE(PJ_STUN_SC_BAD_REQUEST); |
| } |
| |
| /* Now calculate HMAC of the message. */ |
| pj_hmac_sha1_init(&ctx, (pj_uint8_t*)key->ptr, (unsigned)key->slen); |
| |
| #if PJ_STUN_OLD_STYLE_MI_FINGERPRINT |
| /* Pre rfc3489bis-06 style of calculation */ |
| pj_hmac_sha1_update(&ctx, pkt, 20); |
| #else |
| /* First calculate HMAC for the header. |
| * The calculation is different depending on whether FINGERPRINT attribute |
| * is present in the message. |
| */ |
| if (has_attr_beyond_mi) { |
| pj_uint8_t hdr_copy[20]; |
| pj_memcpy(hdr_copy, pkt, 20); |
| PUT_VAL16(hdr_copy, 2, (pj_uint16_t)(amsgi_pos+24)); |
| pj_hmac_sha1_update(&ctx, hdr_copy, 20); |
| } else { |
| pj_hmac_sha1_update(&ctx, pkt, 20); |
| } |
| #endif /* PJ_STUN_OLD_STYLE_MI_FINGERPRINT */ |
| |
| /* Now update with the message body */ |
| pj_hmac_sha1_update(&ctx, pkt+20, amsgi_pos); |
| #if PJ_STUN_OLD_STYLE_MI_FINGERPRINT |
| // This is no longer necessary as per rfc3489bis-08 |
| if ((amsgi_pos+20) & 0x3F) { |
| pj_uint8_t zeroes[64]; |
| pj_bzero(zeroes, sizeof(zeroes)); |
| pj_hmac_sha1_update(&ctx, zeroes, 64-((amsgi_pos+20) & 0x3F)); |
| } |
| #endif |
| pj_hmac_sha1_final(&ctx, digest); |
| |
| /* Compare HMACs */ |
| if (pj_memcmp(amsgi->hmac, digest, 20)) { |
| /* HMAC value mismatch */ |
| return PJ_STATUS_FROM_STUN_CODE(PJ_STUN_SC_UNAUTHORIZED); |
| } |
| |
| /* Everything looks okay! */ |
| return PJ_SUCCESS; |
| } |
| |