henrike@webrtc.org | a7b9818 | 2014-02-21 15:51:43 +0000 | [diff] [blame] | 1 | /* |
| 2 | * libjingle |
| 3 | * Copyright 2014 Google Inc. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions are met: |
| 7 | * |
| 8 | * 1. Redistributions of source code must retain the above copyright notice, |
| 9 | * this list of conditions and the following disclaimer. |
| 10 | * 2. Redistributions in binary form must reproduce the above copyright notice, |
| 11 | * this list of conditions and the following disclaimer in the documentation |
| 12 | * and/or other materials provided with the distribution. |
| 13 | * 3. The name of the author may not be used to endorse or promote products |
| 14 | * derived from this software without specific prior written permission. |
| 15 | * |
| 16 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED |
| 17 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
| 18 | * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO |
| 19 | * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| 20 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| 21 | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; |
| 22 | * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
| 23 | * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR |
| 24 | * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
| 25 | * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 26 | */ |
| 27 | |
| 28 | #ifndef TALK_SESSION_MEDIA_EXTERNAL_HMAC_H_ |
| 29 | #define TALK_SESSION_MEDIA_EXTERNAL_HMAC_H_ |
| 30 | |
| 31 | // External libsrtp HMAC auth module which implements methods defined in |
| 32 | // auth_type_t. |
| 33 | // The default auth module will be replaced only when the ENABLE_EXTERNAL_AUTH |
| 34 | // flag is enabled. This allows us to access to authentication keys, |
| 35 | // as the default auth implementation doesn't provide access and avoids |
| 36 | // hashing each packet twice. |
| 37 | |
| 38 | // How will libsrtp select this module? |
| 39 | // Libsrtp defines authentication function types identified by an unsigned |
| 40 | // integer, e.g. HMAC_SHA1 is 3. Using authentication ids, the application |
| 41 | // can plug any desired authentication modules into libsrtp. |
| 42 | // libsrtp also provides a mechanism to select different auth functions for |
| 43 | // individual streams. This can be done by setting the right value in |
| 44 | // the auth_type of srtp_policy_t. The application must first register auth |
| 45 | // functions and the corresponding authentication id using |
| 46 | // crypto_kernel_replace_auth_type function. |
| 47 | #if defined(HAVE_SRTP) && defined(ENABLE_EXTERNAL_AUTH) |
| 48 | |
henrike@webrtc.org | 2d213e4 | 2014-03-06 18:51:21 +0000 | [diff] [blame^] | 49 | #include "talk/base/basictypes.h" |
henrike@webrtc.org | a7b9818 | 2014-02-21 15:51:43 +0000 | [diff] [blame] | 50 | #ifdef SRTP_RELATIVE_PATH |
henrike@webrtc.org | 2d213e4 | 2014-03-06 18:51:21 +0000 | [diff] [blame^] | 51 | #include "auth.h" // NOLINT |
henrike@webrtc.org | a7b9818 | 2014-02-21 15:51:43 +0000 | [diff] [blame] | 52 | #else |
henrike@webrtc.org | 2d213e4 | 2014-03-06 18:51:21 +0000 | [diff] [blame^] | 53 | #include "third_party/libsrtp/crypto/include/auth.h" |
henrike@webrtc.org | a7b9818 | 2014-02-21 15:51:43 +0000 | [diff] [blame] | 54 | #endif // SRTP_RELATIVE_PATH |
| 55 | |
| 56 | #define EXTERNAL_HMAC_SHA1 HMAC_SHA1 + 1 |
| 57 | #define HMAC_KEY_LENGTH 20 |
| 58 | |
| 59 | // The HMAC context structure used to store authentication keys. |
| 60 | // The pointer to the key will be allocated in the external_hmac_init function. |
| 61 | // This pointer is owned by srtp_t in a template context. |
| 62 | typedef struct { |
henrike@webrtc.org | 2d213e4 | 2014-03-06 18:51:21 +0000 | [diff] [blame^] | 63 | uint8 key[HMAC_KEY_LENGTH]; |
henrike@webrtc.org | a7b9818 | 2014-02-21 15:51:43 +0000 | [diff] [blame] | 64 | int key_length; |
| 65 | } external_hmac_ctx_t; |
| 66 | |
| 67 | err_status_t |
| 68 | external_hmac_alloc(auth_t** a, int key_len, int out_len); |
| 69 | |
| 70 | err_status_t |
| 71 | external_hmac_dealloc(auth_t* a); |
| 72 | |
| 73 | err_status_t |
| 74 | external_hmac_init(external_hmac_ctx_t* state, |
| 75 | const uint8_t* key, int key_len); |
| 76 | |
| 77 | err_status_t |
| 78 | external_hmac_start(external_hmac_ctx_t* state); |
| 79 | |
| 80 | err_status_t |
| 81 | external_hmac_update(external_hmac_ctx_t* state, const uint8_t* message, |
| 82 | int msg_octets); |
| 83 | |
| 84 | err_status_t |
| 85 | external_hmac_compute(external_hmac_ctx_t* state, const void* message, |
| 86 | int msg_octets, int tag_len, uint8_t* result); |
| 87 | |
| 88 | err_status_t |
| 89 | external_crypto_init(); |
| 90 | |
| 91 | #endif // defined(HAVE_SRTP) && defined(ENABLE_EXTERNAL_AUTH) |
| 92 | #endif // TALK_SESSION_MEDIA_EXTERNAL_HMAC_H_ |