#include "asterisk.h"
#include "asterisk/options.h"
#include "asterisk/utils.h"
#include "include/sdp_crypto.h"
Go to the source code of this file.
Data Structures | |
struct | sdp_crypto |
Defines | |
#define | SRTP_MASTER_LEN 30 |
#define | SRTP_MASTER_LEN64 (((SRTP_MASTER_LEN) * 8 + 5) / 6 + 1) |
#define | SRTP_MASTERKEY_LEN 16 |
#define | SRTP_MASTERSALT_LEN ((SRTP_MASTER_LEN) - (SRTP_MASTERKEY_LEN)) |
Functions | |
static int | sdp_crypto_activate (struct sdp_crypto *p, int suite_val, unsigned char *remote_key, struct ast_rtp_instance *rtp) |
static struct sdp_crypto * | sdp_crypto_alloc (void) |
const char * | sdp_crypto_attrib (struct sdp_crypto *p) |
void | sdp_crypto_destroy (struct sdp_crypto *crypto) |
int | sdp_crypto_offer (struct sdp_crypto *p) |
int | sdp_crypto_process (struct sdp_crypto *p, const char *attr, struct ast_rtp_instance *rtp) |
sdp_crypto * | sdp_crypto_setup (void) |
static int | set_crypto_policy (struct ast_srtp_policy *policy, int suite_val, const unsigned char *master_key, unsigned long ssrc, int inbound) |
Variables | |
ast_srtp_res * | res_srtp |
ast_srtp_policy_res * | res_srtp_policy |
Specified in RFC 4568
Definition in file sdp_crypto.c.
#define SRTP_MASTER_LEN 30 |
Definition at line 36 of file sdp_crypto.c.
Referenced by sdp_crypto_process(), and sdp_crypto_setup().
#define SRTP_MASTER_LEN64 (((SRTP_MASTER_LEN) * 8 + 5) / 6 + 1) |
Definition at line 39 of file sdp_crypto.c.
#define SRTP_MASTERKEY_LEN 16 |
#define SRTP_MASTERSALT_LEN ((SRTP_MASTER_LEN) - (SRTP_MASTERKEY_LEN)) |
static int sdp_crypto_activate | ( | struct sdp_crypto * | p, | |
int | suite_val, | |||
unsigned char * | remote_key, | |||
struct ast_rtp_instance * | rtp | |||
) | [static] |
Definition at line 129 of file sdp_crypto.c.
References ast_srtp_policy_res::alloc, ast_debug, ast_log(), ast_rtp_engine_srtp_is_registered(), ast_rtp_instance_add_srtp_policy(), ast_rtp_instance_get_stats(), AST_RTP_INSTANCE_STAT_LOCAL_SSRC, ast_srtp_policy_res::destroy, sdp_crypto::local_key, ast_rtp_instance_stats::local_ssrc, LOG_WARNING, res_srtp_policy, and set_crypto_policy().
Referenced by sdp_crypto_process().
00130 { 00131 struct ast_srtp_policy *local_policy = NULL; 00132 struct ast_srtp_policy *remote_policy = NULL; 00133 struct ast_rtp_instance_stats stats = {0,}; 00134 int res = -1; 00135 00136 if (!ast_rtp_engine_srtp_is_registered()) { 00137 return -1; 00138 } 00139 00140 if (!p) { 00141 return -1; 00142 } 00143 00144 if (!(local_policy = res_srtp_policy->alloc())) { 00145 return -1; 00146 } 00147 00148 if (!(remote_policy = res_srtp_policy->alloc())) { 00149 goto err; 00150 } 00151 00152 if (ast_rtp_instance_get_stats(rtp, &stats, AST_RTP_INSTANCE_STAT_LOCAL_SSRC)) { 00153 goto err; 00154 } 00155 00156 if (set_crypto_policy(local_policy, suite_val, p->local_key, stats.local_ssrc, 0) < 0) { 00157 goto err; 00158 } 00159 00160 if (set_crypto_policy(remote_policy, suite_val, remote_key, 0, 1) < 0) { 00161 goto err; 00162 } 00163 00164 /* FIXME MIKMA */ 00165 /* ^^^ I wish I knew what needed fixing... */ 00166 if (ast_rtp_instance_add_srtp_policy(rtp, local_policy)) { 00167 ast_log(LOG_WARNING, "Could not set local SRTP policy\n"); 00168 goto err; 00169 } 00170 00171 if (ast_rtp_instance_add_srtp_policy(rtp, remote_policy)) { 00172 ast_log(LOG_WARNING, "Could not set remote SRTP policy\n"); 00173 goto err; 00174 } 00175 00176 ast_debug(1 , "SRTP policy activated\n"); 00177 res = 0; 00178 00179 err: 00180 if (local_policy) { 00181 res_srtp_policy->destroy(local_policy); 00182 } 00183 00184 if (remote_policy) { 00185 res_srtp_policy->destroy(remote_policy); 00186 } 00187 00188 return res; 00189 }
static struct sdp_crypto* sdp_crypto_alloc | ( | void | ) | [static] |
Definition at line 52 of file sdp_crypto.c.
References ast_calloc.
Referenced by sdp_crypto_setup().
00053 { 00054 struct sdp_crypto *crypto; 00055 00056 return crypto = ast_calloc(1, sizeof(*crypto)); 00057 }
const char* sdp_crypto_attrib | ( | struct sdp_crypto * | p | ) |
Definition at line 306 of file sdp_crypto.c.
References sdp_crypto::a_crypto.
Referenced by get_crypto_attrib().
00307 { 00308 return p->a_crypto; 00309 }
void sdp_crypto_destroy | ( | struct sdp_crypto * | crypto | ) |
Definition at line 59 of file sdp_crypto.c.
References sdp_crypto::a_crypto, and ast_free.
Referenced by sdp_crypto_setup(), and sip_srtp_destroy().
00060 { 00061 ast_free(crypto->a_crypto); 00062 crypto->a_crypto = NULL; 00063 ast_free(crypto); 00064 }
int sdp_crypto_offer | ( | struct sdp_crypto * | p | ) |
Definition at line 286 of file sdp_crypto.c.
References sdp_crypto::a_crypto, ast_free, ast_strdup, and sdp_crypto::local_key64.
Referenced by get_crypto_attrib().
00287 { 00288 char crypto_buf[128]; 00289 const char *crypto_suite = "AES_CM_128_HMAC_SHA1_80"; /* Crypto offer */ 00290 00291 if (p->a_crypto) { 00292 ast_free(p->a_crypto); 00293 } 00294 00295 if (snprintf(crypto_buf, sizeof(crypto_buf), "a=crypto:1 %s inline:%s\r\n", crypto_suite, p->local_key64) < 1) { 00296 return -1; 00297 } 00298 00299 if (!(p->a_crypto = ast_strdup(crypto_buf))) { 00300 return -1; 00301 } 00302 00303 return 0; 00304 }
int sdp_crypto_process | ( | struct sdp_crypto * | p, | |
const char * | attr, | |||
struct ast_rtp_instance * | rtp | |||
) |
Definition at line 191 of file sdp_crypto.c.
References sdp_crypto::a_crypto, AST_AES_CM_128_HMAC_SHA1_32, AST_AES_CM_128_HMAC_SHA1_80, ast_base64decode(), ast_calloc, ast_log(), ast_rtp_engine_srtp_is_registered(), ast_strdupa, sdp_crypto::local_key64, LOG_ERROR, LOG_NOTICE, LOG_WARNING, sdp_crypto_activate(), SRTP_MASTER_LEN, str, and strsep().
Referenced by process_crypto().
00192 { 00193 char *str = NULL; 00194 char *tag = NULL; 00195 char *suite = NULL; 00196 char *key_params = NULL; 00197 char *key_param = NULL; 00198 char *session_params = NULL; 00199 char *key_salt = NULL; 00200 char *lifetime = NULL; 00201 int found = 0; 00202 int attr_len = strlen(attr); 00203 int key_len = 0; 00204 int suite_val = 0; 00205 unsigned char remote_key[SRTP_MASTER_LEN]; 00206 00207 if (!ast_rtp_engine_srtp_is_registered()) { 00208 return -1; 00209 } 00210 00211 str = ast_strdupa(attr); 00212 00213 strsep(&str, ":"); 00214 tag = strsep(&str, " "); 00215 suite = strsep(&str, " "); 00216 key_params = strsep(&str, " "); 00217 session_params = strsep(&str, " "); 00218 00219 if (!tag || !suite) { 00220 ast_log(LOG_WARNING, "Unrecognized a=%s", attr); 00221 return -1; 00222 } 00223 00224 if (session_params) { 00225 ast_log(LOG_WARNING, "Unsupported crypto parameters: %s", session_params); 00226 return -1; 00227 } 00228 00229 if (!strcmp(suite, "AES_CM_128_HMAC_SHA1_80")) { 00230 suite_val = AST_AES_CM_128_HMAC_SHA1_80; 00231 } else if (!strcmp(suite, "AES_CM_128_HMAC_SHA1_32")) { 00232 suite_val = AST_AES_CM_128_HMAC_SHA1_32; 00233 } else { 00234 ast_log(LOG_WARNING, "Unsupported crypto suite: %s\n", suite); 00235 return -1; 00236 } 00237 00238 while ((key_param = strsep(&key_params, ";"))) { 00239 char *method = NULL; 00240 char *info = NULL; 00241 00242 method = strsep(&key_param, ":"); 00243 info = strsep(&key_param, ";"); 00244 00245 if (!strcmp(method, "inline")) { 00246 key_salt = strsep(&info, "|"); 00247 lifetime = strsep(&info, "|"); 00248 00249 if (lifetime) { 00250 ast_log(LOG_NOTICE, "Crypto life time unsupported: %s\n", attr); 00251 continue; 00252 } 00253 00254 found = 1; 00255 break; 00256 } 00257 } 00258 00259 if (!found) { 00260 ast_log(LOG_NOTICE, "SRTP crypto offer not acceptable\n"); 00261 return -1; 00262 } 00263 00264 00265 if ((key_len = ast_base64decode(remote_key, key_salt, sizeof(remote_key))) != SRTP_MASTER_LEN) { 00266 ast_log(LOG_WARNING, "SRTP sdescriptions key %d != %d\n", key_len, SRTP_MASTER_LEN); 00267 return -1; 00268 } 00269 00270 if (sdp_crypto_activate(p, suite_val, remote_key, rtp) < 0) { 00271 return -1; 00272 } 00273 00274 if (!p->a_crypto) { 00275 if (!(p->a_crypto = ast_calloc(1, attr_len + 11))) { 00276 ast_log(LOG_ERROR, "Could not allocate memory for a_crypto\n"); 00277 return -1; 00278 } 00279 00280 snprintf(p->a_crypto, attr_len + 10, "a=crypto:%s %s inline:%s\r\n", tag, suite, p->local_key64); 00281 } 00282 00283 return 0; 00284 }
struct sdp_crypto* sdp_crypto_setup | ( | void | ) |
Definition at line 66 of file sdp_crypto.c.
References ast_base64decode(), ast_base64encode(), ast_debug, ast_free, ast_log(), ast_rtp_engine_srtp_is_registered(), ast_srtp_res::get_random, sdp_crypto::local_key, sdp_crypto::local_key64, LOG_ERROR, res_srtp, sdp_crypto_alloc(), sdp_crypto_destroy(), and SRTP_MASTER_LEN.
Referenced by get_crypto_attrib(), and process_crypto().
00067 { 00068 struct sdp_crypto *p; 00069 int key_len; 00070 unsigned char remote_key[SRTP_MASTER_LEN]; 00071 00072 if (!ast_rtp_engine_srtp_is_registered()) { 00073 return NULL; 00074 } 00075 00076 if (!(p = sdp_crypto_alloc())) { 00077 return NULL; 00078 } 00079 00080 if (res_srtp->get_random(p->local_key, sizeof(p->local_key)) < 0) { 00081 sdp_crypto_destroy(p); 00082 return NULL; 00083 } 00084 00085 ast_base64encode(p->local_key64, p->local_key, SRTP_MASTER_LEN, sizeof(p->local_key64)); 00086 00087 key_len = ast_base64decode(remote_key, p->local_key64, sizeof(remote_key)); 00088 00089 if (key_len != SRTP_MASTER_LEN) { 00090 ast_log(LOG_ERROR, "base64 encode/decode bad len %d != %d\n", key_len, SRTP_MASTER_LEN); 00091 ast_free(p); 00092 return NULL; 00093 } 00094 00095 if (memcmp(remote_key, p->local_key, SRTP_MASTER_LEN)) { 00096 ast_log(LOG_ERROR, "base64 encode/decode bad key\n"); 00097 ast_free(p); 00098 return NULL; 00099 } 00100 00101 ast_debug(1 , "local_key64 %s len %zu\n", p->local_key64, strlen(p->local_key64)); 00102 00103 return p; 00104 }
static int set_crypto_policy | ( | struct ast_srtp_policy * | policy, | |
int | suite_val, | |||
const unsigned char * | master_key, | |||
unsigned long | ssrc, | |||
int | inbound | |||
) | [static] |
Definition at line 106 of file sdp_crypto.c.
References ast_log(), ast_rtp_engine_srtp_is_registered(), LOG_WARNING, res_srtp_policy, ast_srtp_policy_res::set_master_key, ast_srtp_policy_res::set_ssrc, ast_srtp_policy_res::set_suite, SRTP_MASTERKEY_LEN, and SRTP_MASTERSALT_LEN.
Referenced by sdp_crypto_activate().
00107 { 00108 const unsigned char *master_salt = NULL; 00109 00110 if (!ast_rtp_engine_srtp_is_registered()) { 00111 return -1; 00112 } 00113 00114 master_salt = master_key + SRTP_MASTERKEY_LEN; 00115 if (res_srtp_policy->set_master_key(policy, master_key, SRTP_MASTERKEY_LEN, master_salt, SRTP_MASTERSALT_LEN) < 0) { 00116 return -1; 00117 } 00118 00119 if (res_srtp_policy->set_suite(policy, suite_val)) { 00120 ast_log(LOG_WARNING, "Could not set remote SRTP suite\n"); 00121 return -1; 00122 } 00123 00124 res_srtp_policy->set_ssrc(policy, ssrc, inbound); 00125 00126 return 0; 00127 }
struct ast_srtp_res* res_srtp |
Definition at line 44 of file rtp_engine.c.
Referenced by __rtp_recvfrom(), __rtp_sendto(), ast_rtp_change_source(), ast_rtp_engine_register_srtp(), ast_rtp_engine_srtp_is_registered(), ast_rtp_engine_unregister_srtp(), ast_rtp_instance_add_srtp_policy(), instance_destructor(), and sdp_crypto_setup().
struct ast_srtp_policy_res* res_srtp_policy |
Definition at line 45 of file rtp_engine.c.
Referenced by ast_rtp_engine_register_srtp(), ast_rtp_engine_srtp_is_registered(), ast_rtp_engine_unregister_srtp(), sdp_crypto_activate(), and set_crypto_policy().