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res_srtp: Enable AES-256 and AES-GCM.
ASTERISK-26190 #close Change-Id: I11326d80edd656524a51a19450e586c583aa0a0b
This commit is contained in:
Alexander Traud
385
main/sdp_srtp.c
385
main/sdp_srtp.c
@@ -20,8 +20,7 @@
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*
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* \brief SRTP and SDP Security descriptions
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*
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* Specified in RFC 3711
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* Specified in RFC 4568
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* Specified in RFC 3711, 6188, 7714, and 4568
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*
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* \author Mikael Magnusson <mikma@users.sourceforge.net>
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*/
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@@ -34,15 +33,15 @@
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ASTERISK_REGISTER_FILE()
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#include <math.h>
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#include "asterisk/options.h"
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#include "asterisk/utils.h"
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#include "asterisk/sdp_srtp.h"
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#include <math.h> /* for pow */
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#include <srtp/srtp.h> /* for SRTP_MAX_KEY_LEN, etc */
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#define SRTP_MASTER_LEN 30
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#define SRTP_MASTERKEY_LEN 16
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#define SRTP_MASTERSALT_LEN ((SRTP_MASTER_LEN) - (SRTP_MASTERKEY_LEN))
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#define SRTP_MASTER_LEN64 (((SRTP_MASTER_LEN) * 8 + 5) / 6 + 1)
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#include "asterisk/linkedlists.h" /* for AST_LIST_NEXT, etc */
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#include "asterisk/logger.h" /* for ast_log, LOG_ERROR, etc */
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#include "asterisk/rtp_engine.h" /* for ast_rtp_engine_dtls, etc */
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#include "asterisk/sdp_srtp.h" /* for ast_sdp_srtp, etc */
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#include "asterisk/strings.h" /* for ast_strlen_zero */
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#include "asterisk/utils.h" /* for ast_set_flag, ast_test_flag, etc */
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extern struct ast_srtp_res *res_srtp;
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extern struct ast_srtp_policy_res *res_srtp_policy;
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@@ -59,22 +58,31 @@ struct ast_sdp_srtp *ast_sdp_srtp_alloc(void)
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void ast_sdp_srtp_destroy(struct ast_sdp_srtp *srtp)
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{
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if (srtp->crypto) {
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ast_sdp_crypto_destroy(srtp->crypto);
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struct ast_sdp_srtp *next;
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for (next = AST_LIST_NEXT(srtp, sdp_srtp_list);
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srtp;
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srtp = next, next = srtp ? AST_LIST_NEXT(srtp, sdp_srtp_list) : NULL) {
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if (srtp->crypto) {
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ast_sdp_crypto_destroy(srtp->crypto);
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}
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srtp->crypto = NULL;
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ast_free(srtp);
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}
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srtp->crypto = NULL;
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ast_free(srtp);
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}
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struct ast_sdp_crypto {
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char *a_crypto;
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unsigned char local_key[SRTP_MASTER_LEN];
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unsigned char local_key[SRTP_MAX_KEY_LEN];
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int tag;
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char local_key64[SRTP_MASTER_LEN64];
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unsigned char remote_key[SRTP_MASTER_LEN];
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char local_key64[((SRTP_MAX_KEY_LEN) * 8 + 5) / 6 + 1];
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unsigned char remote_key[SRTP_MAX_KEY_LEN];
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int key_len;
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};
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static int set_crypto_policy(struct ast_srtp_policy *policy, int suite_val, const unsigned char *master_key, unsigned long ssrc, int inbound);
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static struct ast_sdp_crypto *sdp_crypto_alloc(const int key_len);
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static struct ast_sdp_crypto *crypto_init_keys(struct ast_sdp_crypto *p, const int key_len);
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static int set_crypto_policy(struct ast_srtp_policy *policy, int suite_val, const unsigned char *master_key, int key_len, unsigned long ssrc, int inbound);
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void ast_sdp_crypto_destroy(struct ast_sdp_crypto *crypto)
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{
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@@ -83,11 +91,36 @@ void ast_sdp_crypto_destroy(struct ast_sdp_crypto *crypto)
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ast_free(crypto);
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}
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struct ast_sdp_crypto *ast_sdp_crypto_alloc(void)
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static struct ast_sdp_crypto *crypto_init_keys(struct ast_sdp_crypto *p, const int key_len)
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{
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struct ast_sdp_crypto *p;
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int key_len;
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unsigned char remote_key[SRTP_MASTER_LEN];
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unsigned char remote_key[key_len];
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if (res_srtp->get_random(p->local_key, key_len) < 0) {
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return NULL;
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}
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ast_base64encode(p->local_key64, p->local_key, key_len, sizeof(p->local_key64));
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p->key_len = ast_base64decode(remote_key, p->local_key64, sizeof(remote_key));
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if (p->key_len != key_len) {
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ast_log(LOG_ERROR, "base64 encode/decode bad len %d != %d\n", p->key_len, key_len);
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return NULL;
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}
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if (memcmp(remote_key, p->local_key, p->key_len)) {
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ast_log(LOG_ERROR, "base64 encode/decode bad key\n");
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return NULL;
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}
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ast_debug(1 , "local_key64 %s len %zu\n", p->local_key64, strlen(p->local_key64));
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return p;
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}
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static struct ast_sdp_crypto *sdp_crypto_alloc(const int key_len)
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{
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struct ast_sdp_crypto *p, *result;
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if (!ast_rtp_engine_srtp_is_registered()) {
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return NULL;
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@@ -98,42 +131,27 @@ struct ast_sdp_crypto *ast_sdp_crypto_alloc(void)
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}
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p->tag = 1;
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if (res_srtp->get_random(p->local_key, sizeof(p->local_key)) < 0) {
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/* default is a key which uses AST_AES_CM_128_HMAC_SHA1_xx */
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result = crypto_init_keys(p, key_len);
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if (!result) {
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ast_sdp_crypto_destroy(p);
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return NULL;
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}
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ast_base64encode(p->local_key64, p->local_key, SRTP_MASTER_LEN, sizeof(p->local_key64));
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key_len = ast_base64decode(remote_key, p->local_key64, sizeof(remote_key));
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if (key_len != SRTP_MASTER_LEN) {
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ast_log(LOG_ERROR, "base64 encode/decode bad len %d != %d\n", key_len, SRTP_MASTER_LEN);
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ast_sdp_crypto_destroy(p);
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return NULL;
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}
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if (memcmp(remote_key, p->local_key, SRTP_MASTER_LEN)) {
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ast_log(LOG_ERROR, "base64 encode/decode bad key\n");
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ast_sdp_crypto_destroy(p);
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return NULL;
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}
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ast_debug(1 , "local_key64 %s len %zu\n", p->local_key64, strlen(p->local_key64));
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return p;
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return result;
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}
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static int set_crypto_policy(struct ast_srtp_policy *policy, int suite_val, const unsigned char *master_key, unsigned long ssrc, int inbound)
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struct ast_sdp_crypto *ast_sdp_crypto_alloc(void)
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{
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const unsigned char *master_salt = NULL;
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return sdp_crypto_alloc(SRTP_MASTER_KEY_LEN);
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}
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static int set_crypto_policy(struct ast_srtp_policy *policy, int suite_val, const unsigned char *master_key, int key_len, unsigned long ssrc, int inbound)
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{
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if (!ast_rtp_engine_srtp_is_registered()) {
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return -1;
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}
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master_salt = master_key + SRTP_MASTERKEY_LEN;
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if (res_srtp_policy->set_master_key(policy, master_key, SRTP_MASTERKEY_LEN, master_salt, SRTP_MASTERSALT_LEN) < 0) {
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if (res_srtp_policy->set_master_key(policy, master_key, key_len, NULL, 0) < 0) {
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return -1;
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}
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@@ -147,7 +165,7 @@ static int set_crypto_policy(struct ast_srtp_policy *policy, int suite_val, cons
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return 0;
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}
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static int crypto_activate(struct ast_sdp_crypto *p, int suite_val, unsigned char *remote_key, struct ast_rtp_instance *rtp)
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static int crypto_activate(struct ast_sdp_crypto *p, int suite_val, unsigned char *remote_key, int key_len, struct ast_rtp_instance *rtp)
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{
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struct ast_srtp_policy *local_policy = NULL;
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struct ast_srtp_policy *remote_policy = NULL;
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@@ -174,11 +192,11 @@ static int crypto_activate(struct ast_sdp_crypto *p, int suite_val, unsigned cha
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goto err;
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}
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if (set_crypto_policy(local_policy, suite_val, p->local_key, stats.local_ssrc, 0) < 0) {
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if (set_crypto_policy(local_policy, suite_val, p->local_key, key_len, stats.local_ssrc, 0) < 0) {
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goto err;
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}
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if (set_crypto_policy(remote_policy, suite_val, remote_key, 0, 1) < 0) {
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if (set_crypto_policy(remote_policy, suite_val, remote_key, key_len, 0, 1) < 0) {
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goto err;
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}
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@@ -215,12 +233,15 @@ int ast_sdp_crypto_process(struct ast_rtp_instance *rtp, struct ast_sdp_srtp *sr
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char *lifetime = NULL; /* Key lifetime (# of RTP packets) */
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char *mki = NULL; /* Master Key Index */
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int found = 0;
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int key_len = 0;
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int key_len_from_sdp;
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int key_len_expected;
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int tag_from_sdp;
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int suite_val = 0;
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unsigned char remote_key[SRTP_MASTER_LEN];
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int taglen = 0;
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unsigned char remote_key[SRTP_MAX_KEY_LEN];
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int taglen;
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double sdes_lifetime;
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struct ast_sdp_crypto *crypto = srtp->crypto;
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struct ast_sdp_crypto *crypto;
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struct ast_sdp_srtp *tmp;
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if (!ast_rtp_engine_srtp_is_registered()) {
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return -1;
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@@ -239,7 +260,7 @@ int ast_sdp_crypto_process(struct ast_rtp_instance *rtp, struct ast_sdp_srtp *sr
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}
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/* RFC4568 9.1 - tag is 1-9 digits, greater than zero */
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if (sscanf(tag, "%30d", &crypto->tag) != 1 || crypto->tag <= 0 || crypto->tag > 999999999) {
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if (sscanf(tag, "%30d", &tag_from_sdp) != 1 || tag_from_sdp <= 0 || tag_from_sdp > 999999999) {
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ast_log(LOG_WARNING, "Unacceptable a=crypto tag: %s\n", tag);
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return -1;
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}
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@@ -249,16 +270,107 @@ int ast_sdp_crypto_process(struct ast_rtp_instance *rtp, struct ast_sdp_srtp *sr
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return -1;
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}
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/* On egress, Asterisk sent several crypto lines in the SIP/SDP offer
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The remote party might have choosen another line than the first */
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for (tmp = srtp; tmp && tmp->crypto && tmp->crypto->tag != tag_from_sdp;) {
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tmp = AST_LIST_NEXT(tmp, sdp_srtp_list);
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}
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if (tmp) { /* tag matched an already created crypto line */
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unsigned int flags = tmp->flags;
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/* Make that crypto line the head of the list, not by changing the
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list structure but by exchanging the content of the list members */
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crypto = tmp->crypto;
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tmp->crypto = srtp->crypto;
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tmp->flags = srtp->flags;
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srtp->crypto = crypto;
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srtp->flags = flags;
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} else {
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crypto = srtp->crypto;
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crypto->tag = tag_from_sdp;
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}
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if (!strcmp(suite, "AES_CM_128_HMAC_SHA1_80")) {
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suite_val = AST_AES_CM_128_HMAC_SHA1_80;
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ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_80);
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taglen = 80;
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key_len_expected = 30;
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} else if (!strcmp(suite, "AES_CM_128_HMAC_SHA1_32")) {
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suite_val = AST_AES_CM_128_HMAC_SHA1_32;
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ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_32);
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taglen = 32;
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key_len_expected = 30;
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#ifdef HAVE_SRTP_192
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} else if (!strcmp(suite, "AES_192_CM_HMAC_SHA1_80")) {
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suite_val = AST_AES_CM_192_HMAC_SHA1_80;
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ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_80);
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ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_192);
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key_len_expected = 38;
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} else if (!strcmp(suite, "AES_192_CM_HMAC_SHA1_32")) {
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suite_val = AST_AES_CM_192_HMAC_SHA1_32;
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ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_32);
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ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_192);
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key_len_expected = 38;
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/* RFC used a different name while in draft, some still use that */
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} else if (!strcmp(suite, "AES_CM_192_HMAC_SHA1_80")) {
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suite_val = AST_AES_CM_192_HMAC_SHA1_80;
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ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_80);
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ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_192);
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ast_set_flag(srtp, AST_SRTP_CRYPTO_OLD_NAME);
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key_len_expected = 38;
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} else if (!strcmp(suite, "AES_CM_192_HMAC_SHA1_32")) {
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suite_val = AST_AES_CM_192_HMAC_SHA1_32;
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ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_32);
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ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_192);
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ast_set_flag(srtp, AST_SRTP_CRYPTO_OLD_NAME);
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key_len_expected = 38;
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#endif
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#ifdef HAVE_SRTP_256
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} else if (!strcmp(suite, "AES_256_CM_HMAC_SHA1_80")) {
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suite_val = AST_AES_CM_256_HMAC_SHA1_80;
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ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_80);
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ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_256);
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key_len_expected = 46;
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} else if (!strcmp(suite, "AES_256_CM_HMAC_SHA1_32")) {
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suite_val = AST_AES_CM_256_HMAC_SHA1_32;
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ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_32);
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ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_256);
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key_len_expected = 46;
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/* RFC used a different name while in draft, some still use that */
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} else if (!strcmp(suite, "AES_CM_256_HMAC_SHA1_80")) {
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suite_val = AST_AES_CM_256_HMAC_SHA1_80;
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ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_80);
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ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_256);
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ast_set_flag(srtp, AST_SRTP_CRYPTO_OLD_NAME);
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key_len_expected = 46;
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} else if (!strcmp(suite, "AES_CM_256_HMAC_SHA1_32")) {
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suite_val = AST_AES_CM_256_HMAC_SHA1_32;
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ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_32);
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ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_256);
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ast_set_flag(srtp, AST_SRTP_CRYPTO_OLD_NAME);
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key_len_expected = 46;
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#endif
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#ifdef HAVE_SRTP_GCM
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} else if (!strcmp(suite, "AEAD_AES_128_GCM")) {
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suite_val = AST_AES_GCM_128;
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ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_16);
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key_len_expected = AES_128_GCM_KEYSIZE_WSALT;
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} else if (!strcmp(suite, "AEAD_AES_256_GCM")) {
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suite_val = AST_AES_GCM_256;
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ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_16);
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ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_256);
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key_len_expected = AES_256_GCM_KEYSIZE_WSALT;
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/* RFC contained a (too) short auth tag for RTP media, some still use that */
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} else if (!strcmp(suite, "AEAD_AES_128_GCM_8")) {
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suite_val = AST_AES_GCM_128_8;
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ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_8);
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key_len_expected = AES_128_GCM_KEYSIZE_WSALT;
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} else if (!strcmp(suite, "AEAD_AES_256_GCM_8")) {
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suite_val = AST_AES_GCM_256_8;
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ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_8);
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ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_256);
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key_len_expected = AES_256_GCM_KEYSIZE_WSALT;
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#endif
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} else {
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ast_log(LOG_WARNING, "Unsupported crypto suite: %s\n", suite);
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ast_verb(1, "Unsupported crypto suite: %s\n", suite);
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return -1;
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}
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@@ -341,23 +453,55 @@ int ast_sdp_crypto_process(struct ast_rtp_instance *rtp, struct ast_sdp_srtp *sr
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return -1;
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}
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key_len = ast_base64decode(remote_key, key_salt, sizeof(remote_key));
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if (key_len != SRTP_MASTER_LEN) {
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ast_log(LOG_WARNING, "SRTP descriptions key length '%d' != master length '%d'\n",
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key_len, SRTP_MASTER_LEN);
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key_len_from_sdp = ast_base64decode(remote_key, key_salt, sizeof(remote_key));
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if (key_len_from_sdp != key_len_expected) {
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ast_log(LOG_WARNING, "SRTP descriptions key length is '%d', not '%d'\n",
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key_len_from_sdp, key_len_expected);
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return -1;
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}
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if (!memcmp(crypto->remote_key, remote_key, sizeof(crypto->remote_key))) {
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/* on default, the key is 30 (AES-128); throw that away (only) when the suite changed actually */
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/* ingress: optional, but saves one expensive call to get_random(.) */
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/* egress: required, because the local key was communicated before the remote key is processed */
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if (crypto->key_len != key_len_from_sdp) {
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if (!crypto_init_keys(crypto, key_len_from_sdp)) {
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return -1;
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}
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} else if (!memcmp(crypto->remote_key, remote_key, key_len_from_sdp)) {
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ast_debug(1, "SRTP remote key unchanged; maintaining current policy\n");
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ast_set_flag(srtp, AST_SRTP_CRYPTO_OFFER_OK);
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return 0;
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}
|
||||
memcpy(crypto->remote_key, remote_key, sizeof(crypto->remote_key));
|
||||
|
||||
if (crypto_activate(crypto, suite_val, remote_key, rtp) < 0) {
|
||||
if (key_len_from_sdp > sizeof(crypto->remote_key)) {
|
||||
ast_log(LOG_ERROR,
|
||||
"SRTP key buffer is %zu although it must be at least %d bytes\n",
|
||||
sizeof(crypto->remote_key), key_len_from_sdp);
|
||||
return -1;
|
||||
}
|
||||
memcpy(crypto->remote_key, remote_key, key_len_from_sdp);
|
||||
|
||||
if (crypto_activate(crypto, suite_val, remote_key, key_len_from_sdp, rtp) < 0) {
|
||||
return -1;
|
||||
}
|
||||
|
||||
if (ast_test_flag(srtp, AST_SRTP_CRYPTO_TAG_32)) {
|
||||
taglen = 32;
|
||||
} else if (ast_test_flag(srtp, AST_SRTP_CRYPTO_TAG_16)) {
|
||||
taglen = 16;
|
||||
} else if (ast_test_flag(srtp, AST_SRTP_CRYPTO_TAG_8)) {
|
||||
taglen = 8;
|
||||
} else {
|
||||
taglen = 80;
|
||||
}
|
||||
if (ast_test_flag(srtp, AST_SRTP_CRYPTO_AES_256)) {
|
||||
taglen |= 0x0200;
|
||||
} else if (ast_test_flag(srtp, AST_SRTP_CRYPTO_AES_192)) {
|
||||
taglen |= 0x0100;
|
||||
}
|
||||
if (ast_test_flag(srtp, AST_SRTP_CRYPTO_OLD_NAME)) {
|
||||
taglen |= 0x0080;
|
||||
}
|
||||
|
||||
/* Finally, rebuild the crypto line */
|
||||
if (ast_sdp_crypto_build_offer(crypto, taglen)) {
|
||||
@@ -375,10 +519,30 @@ int ast_sdp_crypto_build_offer(struct ast_sdp_crypto *p, int taglen)
|
||||
ast_free(p->a_crypto);
|
||||
}
|
||||
|
||||
if (ast_asprintf(&p->a_crypto, "%d AES_CM_128_HMAC_SHA1_%i inline:%s",
|
||||
p->tag, taglen, p->local_key64) == -1) {
|
||||
ast_log(LOG_ERROR, "Could not allocate memory for crypto line\n");
|
||||
return -1;
|
||||
if ((taglen & 0x007f) == 8) {
|
||||
if (ast_asprintf(&p->a_crypto, "%d AEAD_AES_%d_GCM_%d inline:%s",
|
||||
p->tag, 128 + ((taglen & 0x0300) >> 2), taglen & 0x007f, p->local_key64) == -1) {
|
||||
ast_log(LOG_ERROR, "Could not allocate memory for crypto line\n");
|
||||
return -1;
|
||||
}
|
||||
} else if ((taglen & 0x007f) == 16) {
|
||||
if (ast_asprintf(&p->a_crypto, "%d AEAD_AES_%d_GCM inline:%s",
|
||||
p->tag, 128 + ((taglen & 0x0300) >> 2), p->local_key64) == -1) {
|
||||
ast_log(LOG_ERROR, "Could not allocate memory for crypto line\n");
|
||||
return -1;
|
||||
}
|
||||
} else if ((taglen & 0x0300) && !(taglen & 0x0080)) {
|
||||
if (ast_asprintf(&p->a_crypto, "%d AES_%d_CM_HMAC_SHA1_%d inline:%s",
|
||||
p->tag, 128 + ((taglen & 0x0300) >> 2), taglen & 0x007f, p->local_key64) == -1) {
|
||||
ast_log(LOG_ERROR, "Could not allocate memory for crypto line\n");
|
||||
return -1;
|
||||
}
|
||||
} else {
|
||||
if (ast_asprintf(&p->a_crypto, "%d AES_CM_%d_HMAC_SHA1_%d inline:%s",
|
||||
p->tag, 128 + ((taglen & 0x0300) >> 2), taglen & 0x007f, p->local_key64) == -1) {
|
||||
ast_log(LOG_ERROR, "Could not allocate memory for crypto line\n");
|
||||
return -1;
|
||||
}
|
||||
}
|
||||
|
||||
ast_debug(1, "Crypto line: a=crypto:%s\n", p->a_crypto);
|
||||
@@ -388,7 +552,7 @@ int ast_sdp_crypto_build_offer(struct ast_sdp_crypto *p, int taglen)
|
||||
|
||||
const char *ast_sdp_srtp_get_attrib(struct ast_sdp_srtp *srtp, int dtls_enabled, int default_taglen_32)
|
||||
{
|
||||
int taglen = default_taglen_32 ? 32 : 80;
|
||||
int taglen;
|
||||
|
||||
if (!srtp) {
|
||||
return NULL;
|
||||
@@ -396,7 +560,72 @@ const char *ast_sdp_srtp_get_attrib(struct ast_sdp_srtp *srtp, int dtls_enabled,
|
||||
|
||||
/* Set encryption properties */
|
||||
if (!srtp->crypto) {
|
||||
srtp->crypto = ast_sdp_crypto_alloc();
|
||||
|
||||
if (AST_LIST_NEXT(srtp, sdp_srtp_list)) {
|
||||
srtp->crypto = ast_sdp_crypto_alloc();
|
||||
ast_log(LOG_ERROR, "SRTP SDP list was not empty\n");
|
||||
} else {
|
||||
const int len = default_taglen_32 ? AST_SRTP_CRYPTO_TAG_32 : AST_SRTP_CRYPTO_TAG_80;
|
||||
const int attr[][3] = {
|
||||
/* This array creates the following list:
|
||||
* a=crypto:1 AES_CM_128_HMAC_SHA1_ ...
|
||||
* a=crypto:2 AEAD_AES_128_GCM ...
|
||||
* a=crypto:3 AES_256_CM_HMAC_SHA1_ ...
|
||||
* a=crypto:4 AEAD_AES_256_GCM ...
|
||||
* a=crypto:5 AES_192_CM_HMAC_SHA1_ ...
|
||||
* something like 'AEAD_AES_192_GCM' is not specified by the RFCs
|
||||
*
|
||||
* If you want to prefer another crypto suite or you want to
|
||||
* exclude a suite, change this array and recompile Asterisk.
|
||||
* This list cannot be changed from rtp.conf because you should
|
||||
* know what you are doing. Especially AES-192 and AES-GCM are
|
||||
* broken in many VoIP clients, see
|
||||
* https://github.com/cisco/libsrtp/pull/170
|
||||
* https://github.com/cisco/libsrtp/pull/184
|
||||
* Furthermore, AES-GCM uses a shorter crypto-suite string which
|
||||
* causes Nokia phones based on Symbian/S60 to reject the whole
|
||||
* INVITE with status 500, even if a matching suite was offered.
|
||||
* AES-256 might just waste your processor cycles, especially if
|
||||
* your TLS transport is not secured with equivalent grade, see
|
||||
* https://security.stackexchange.com/q/61361
|
||||
* Therefore, AES-128 was preferred here.
|
||||
*
|
||||
* If you want to enable one of those defines, please, go for
|
||||
* CFLAGS='-DENABLE_SRTP_AES_GCM' ./configure && sudo make install
|
||||
*/
|
||||
{ len, 0, 30 },
|
||||
#if defined(HAVE_SRTP_GCM) && defined(ENABLE_SRTP_AES_GCM)
|
||||
{ AST_SRTP_CRYPTO_TAG_16, 0, AES_128_GCM_KEYSIZE_WSALT },
|
||||
#endif
|
||||
#if defined(HAVE_SRTP_256) && defined(ENABLE_SRTP_AES_256)
|
||||
{ len, AST_SRTP_CRYPTO_AES_256, 46 },
|
||||
#endif
|
||||
#if defined(HAVE_SRTP_GCM) && defined(ENABLE_SRTP_AES_GCM) && defined(ENABLE_SRTP_AES_256)
|
||||
{ AST_SRTP_CRYPTO_TAG_16, AST_SRTP_CRYPTO_AES_256, AES_256_GCM_KEYSIZE_WSALT },
|
||||
#endif
|
||||
#if defined(HAVE_SRTP_192) && defined(ENABLE_SRTP_AES_192)
|
||||
{ len, AST_SRTP_CRYPTO_AES_192, 38 },
|
||||
#endif
|
||||
};
|
||||
struct ast_sdp_srtp *tmp = srtp;
|
||||
int i;
|
||||
|
||||
for (i = 0; i < ARRAY_LEN(attr); i++) {
|
||||
if (attr[i][0]) {
|
||||
ast_set_flag(tmp, attr[i][0]);
|
||||
}
|
||||
if (attr[i][1]) {
|
||||
ast_set_flag(tmp, attr[i][1]);
|
||||
}
|
||||
tmp->crypto = sdp_crypto_alloc(attr[i][2]); /* key_len */
|
||||
tmp->crypto->tag = (i + 1); /* tag starts at 1 */
|
||||
|
||||
if (i < ARRAY_LEN(attr) - 1) {
|
||||
AST_LIST_NEXT(tmp, sdp_srtp_list) = ast_sdp_srtp_alloc();
|
||||
tmp = AST_LIST_NEXT(tmp, sdp_srtp_list);
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if (dtls_enabled) {
|
||||
@@ -409,6 +638,20 @@ const char *ast_sdp_srtp_get_attrib(struct ast_sdp_srtp *srtp, int dtls_enabled,
|
||||
taglen = 80;
|
||||
} else if (ast_test_flag(srtp, AST_SRTP_CRYPTO_TAG_32)) {
|
||||
taglen = 32;
|
||||
} else if (ast_test_flag(srtp, AST_SRTP_CRYPTO_TAG_16)) {
|
||||
taglen = 16;
|
||||
} else if (ast_test_flag(srtp, AST_SRTP_CRYPTO_TAG_8)) {
|
||||
taglen = 8;
|
||||
} else {
|
||||
taglen = default_taglen_32 ? 32 : 80;
|
||||
}
|
||||
if (ast_test_flag(srtp, AST_SRTP_CRYPTO_AES_256)) {
|
||||
taglen |= 0x0200;
|
||||
} else if (ast_test_flag(srtp, AST_SRTP_CRYPTO_AES_192)) {
|
||||
taglen |= 0x0100;
|
||||
}
|
||||
if (ast_test_flag(srtp, AST_SRTP_CRYPTO_OLD_NAME)) {
|
||||
taglen |= 0x0080;
|
||||
}
|
||||
|
||||
if (srtp->crypto && (ast_sdp_crypto_build_offer(srtp->crypto, taglen) >= 0)) {
|
||||
|
||||
Reference in New Issue
Block a user