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diff -purN -x CVS -x '*~' -x '.*' -x 'obj-*' srtp-ws/include/srtp.h srtp/include/srtp.h
--- srtp-ws/include/srtp.h 2009-04-22 19:06:22.000000000 -0400
+++ srtp/include/srtp.h 2009-04-23 15:17:49.000000000 -0400
@@ -225,6 +225,12 @@ typedef struct srtp_policy_t {
* for this stream (if any) */
unsigned long window_size; /**< The window size to use for replay
* protection. */
+ int allow_repeat_tx; /**< Whether retransmissions of
+ * packets with the same sequence number
+ * are allowed. (Note that such repeated
+ * transmissions must have the same RTP
+ * payload, or a severe security weakness
+ * is introduced!) */
struct srtp_policy_t *next; /**< Pointer to next stream policy. */
} srtp_policy_t;
diff -purN -x CVS -x '*~' -x '.*' -x 'obj-*' srtp-ws/include/srtp_priv.h srtp/include/srtp_priv.h
--- srtp-ws/include/srtp_priv.h 2007-06-15 14:17:40.000000000 -0400
+++ srtp/include/srtp_priv.h 2009-04-22 19:27:10.000000000 -0400
@@ -218,6 +218,7 @@ typedef struct srtp_stream_ctx_t {
sec_serv_t rtcp_services;
key_limit_ctx_t *limit;
direction_t direction;
+ int allow_repeat_tx;
ekt_stream_t ekt;
struct srtp_stream_ctx_t *next; /* linked list of streams */
} srtp_stream_ctx_t;
diff -purN -x CVS -x '*~' -x '.*' -x 'obj-*' srtp-ws/srtp/srtp.c srtp/srtp/srtp.c
--- srtp-ws/srtp/srtp.c 2009-04-22 19:18:43.000000000 -0400
+++ srtp/srtp/srtp.c 2009-04-22 19:30:23.000000000 -0400
@@ -280,6 +280,7 @@ srtp_stream_clone(const srtp_stream_ctx_
if (status)
return status;
rdb_init(&str->rtcp_rdb);
+ str->allow_repeat_tx = stream_template->allow_repeat_tx;
/* set ssrc to that provided */
str->ssrc = ssrc;
@@ -525,6 +526,9 @@ srtp_stream_init(srtp_stream_ctx_t *srtp
/* initialize SRTCP replay database */
rdb_init(&srtp->rtcp_rdb);
+ /* initialize allow_repeat_tx */
+ srtp->allow_repeat_tx = p->allow_repeat_tx;
+
/* DAM - no RTCP key limit at present */
/* initialize keys */
@@ -732,9 +736,12 @@ srtp_stream_init(srtp_stream_ctx_t *srtp
*/
delta = rdbx_estimate_index(&stream->rtp_rdbx, &est, ntohs(hdr->seq));
status = rdbx_check(&stream->rtp_rdbx, delta);
- if (status)
- return status; /* we've been asked to reuse an index */
- rdbx_add_index(&stream->rtp_rdbx, delta);
+ if (status) {
+ if (status != err_status_replay_fail || !stream->allow_repeat_tx)
+ return status; /* we've been asked to reuse an index */
+ }
+ else
+ rdbx_add_index(&stream->rtp_rdbx, delta);
#ifdef NO_64BIT_MATH
debug_print2(mod_srtp, "estimated packet index: %08x%08x",
diff -purN -x CVS -x '*~' -x '.*' -x 'obj-*' srtp-ws/test/dtls_srtp_driver.c srtp/test/dtls_srtp_driver.c
--- srtp-ws/test/dtls_srtp_driver.c 2009-04-23 15:50:48.000000000 -0400
+++ srtp/test/dtls_srtp_driver.c 2009-04-23 15:51:11.000000000 -0400
@@ -185,6 +185,7 @@ test_dtls_srtp() {
policy.ssrc.type = ssrc_any_inbound;
policy.ekt = NULL;
policy.window_size = 128;
+ policy.allow_repeat_tx = 0;
policy.next = NULL;
err = srtp_add_stream(s, &policy);
diff -purN -x CVS -x '*~' -x '.*' -x 'obj-*' srtp-ws/test/rtpw.c srtp/test/rtpw.c
--- srtp-ws/test/rtpw.c 2009-04-22 19:16:52.000000000 -0400
+++ srtp/test/rtpw.c 2009-04-23 15:16:18.000000000 -0400
@@ -331,6 +331,7 @@ main (int argc, char *argv[]) {
policy.key = (uint8_t *) key;
policy.next = NULL;
policy.window_size = 128;
+ policy.allow_repeat_tx = 0;
policy.rtp.sec_serv = sec_servs;
policy.rtcp.sec_serv = sec_serv_none; /* we don't do RTCP anyway */
@@ -384,6 +385,7 @@ main (int argc, char *argv[]) {
policy.rtcp.auth_tag_len = 0;
policy.rtcp.sec_serv = sec_serv_none;
policy.window_size = 0;
+ policy.allow_repeat_tx = 0;
policy.next = NULL;
}
diff -purN -x CVS -x '*~' -x '.*' -x 'obj-*' srtp-ws/test/srtp_driver.c srtp/test/srtp_driver.c
--- srtp-ws/test/srtp_driver.c 2009-04-22 19:16:52.000000000 -0400
+++ srtp/test/srtp_driver.c 2009-04-23 15:16:18.000000000 -0400
@@ -323,6 +323,7 @@ main (int argc, char *argv[]) {
policy.key = test_key;
policy.ekt = NULL;
policy.window_size = 128;
+ policy.allow_repeat_tx = 0;
policy.next = NULL;
printf("mips estimate: %e\n", mips);
@@ -992,7 +993,8 @@ srtp_session_print_policy(srtp_t srtp) {
"# rtcp cipher: %s\r\n"
"# rtcp auth: %s\r\n"
"# rtcp services: %s\r\n"
- "# window size: %lu\r\n",
+ "# window size: %lu\r\n"
+ "# tx rtx allowed:%s\r\n",
direction[stream->direction],
stream->rtp_cipher->type->description,
stream->rtp_auth->type->description,
@@ -1000,7 +1002,8 @@ srtp_session_print_policy(srtp_t srtp) {
stream->rtcp_cipher->type->description,
stream->rtcp_auth->type->description,
serv_descr[stream->rtcp_services],
- rdbx_get_window_size(&stream->rtp_rdbx));
+ rdbx_get_window_size(&stream->rtp_rdbx),
+ stream->allow_repeat_tx ? "true" : "false");
}
/* loop over streams in session, printing the policy of each */
@@ -1016,7 +1019,8 @@ srtp_session_print_policy(srtp_t srtp) {
"# rtcp cipher: %s\r\n"
"# rtcp auth: %s\r\n"
"# rtcp services: %s\r\n"
- "# window size: %lu\r\n",
+ "# window size: %lu\r\n"
+ "# tx rtx allowed:%s\r\n",
stream->ssrc,
stream->rtp_cipher->type->description,
stream->rtp_auth->type->description,
@@ -1024,7 +1028,8 @@ srtp_session_print_policy(srtp_t srtp) {
stream->rtcp_cipher->type->description,
stream->rtcp_auth->type->description,
serv_descr[stream->rtcp_services],
- rdbx_get_window_size(&stream->rtp_rdbx));
+ rdbx_get_window_size(&stream->rtp_rdbx),
+ stream->allow_repeat_tx ? "true" : "false");
/* advance to next stream in the list */
stream = stream->next;
@@ -1180,6 +1185,7 @@ srtp_validate() {
policy.key = test_key;
policy.ekt = NULL;
policy.window_size = 128;
+ policy.allow_repeat_tx = 0;
policy.next = NULL;
status = srtp_create(&srtp_snd, &policy);
@@ -1337,6 +1343,7 @@ const srtp_policy_t default_policy = {
test_key,
NULL, /* indicates that EKT is not in use */
128, /* replay window size */
+ 0, /* retransmission not allowed */
NULL
};
@@ -1361,6 +1368,7 @@ const srtp_policy_t aes_tmmh_policy = {
test_key,
NULL, /* indicates that EKT is not in use */
128, /* replay window size */
+ 0, /* retransmission not allowed */
NULL
};
@@ -1385,6 +1393,7 @@ const srtp_policy_t tmmh_only_policy = {
test_key,
NULL, /* indicates that EKT is not in use */
128, /* replay window size */
+ 0, /* retransmission not allowed */
NULL
};
@@ -1409,6 +1418,7 @@ const srtp_policy_t aes_only_policy = {
test_key,
NULL, /* indicates that EKT is not in use */
128, /* replay window size */
+ 0, /* retransmission not allowed */
NULL
};
@@ -1433,6 +1443,7 @@ const srtp_policy_t hmac_only_policy = {
test_key,
NULL, /* indicates that EKT is not in use */
128, /* replay window size */
+ 0, /* retransmission not allowed */
NULL
};
@@ -1457,6 +1468,7 @@ const srtp_policy_t null_policy = {
test_key,
NULL, /* indicates that EKT is not in use */
128, /* replay window size */
+ 0, /* retransmission not allowed */
NULL
};
@@ -1495,6 +1507,7 @@ const srtp_policy_t hmac_only_with_ekt_p
test_key,
&ekt_test_policy, /* indicates that EKT is not in use */
128, /* replay window size */
+ 0, /* retransmission not allowed */
NULL
};
@@ -1548,5 +1561,6 @@ const srtp_policy_t wildcard_policy = {
test_key,
NULL,
128, /* replay window size */
+ 0, /* retransmission not allowed */
NULL
};
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