From 041122c85ddf8609ce3ccb7920de4b3f3cd1ac6e Mon Sep 17 00:00:00 2001 From: George Joseph Date: Fri, 15 Dec 2023 09:37:54 -0700 Subject: [PATCH] res_rtp_asterisk: Fix regression issues with DTLS client check * Since ICE candidates are used for the check and pjproject is required to use ICE, res_rtp_asterisk was failing to compile when pjproject wasn't available. The check is now wrapped with an #ifdef HAVE_PJPROJECT. * The rtp->ice_active_remote_candidates container was being used to check the address on incoming packets but that container doesn't contain peer reflexive candidates discovered during negotiation. This was causing the check to fail where it shouldn't. We now check against pjproject's real_ice->rcand array which will contain those candidates. * Also fixed a bug in ast_sockaddr_from_pj_sockaddr() where we weren't zeroing out sin->sin_zero before returning. This was causing ast_sockaddr_cmp() to always return false when one of the inputs was converted from a pj_sockaddr, even if both inputs had the same address and port. Resolves: #500 Resolves: #503 Resolves: #505 --- include/asterisk/res_pjproject.h | 13 +++++++++++++ res/res_pjproject.c | 22 ++++++++++++++++++++++ res/res_rtp_asterisk.c | 22 ++++++++++------------ 3 files changed, 45 insertions(+), 12 deletions(-) diff --git a/include/asterisk/res_pjproject.h b/include/asterisk/res_pjproject.h index eee8c4eee81..823f5cc5458 100644 --- a/include/asterisk/res_pjproject.h +++ b/include/asterisk/res_pjproject.h @@ -115,4 +115,17 @@ int ast_sockaddr_to_pj_sockaddr(const struct ast_sockaddr *addr, pj_sockaddr *pj */ int ast_sockaddr_from_pj_sockaddr(struct ast_sockaddr *addr, const pj_sockaddr *pjaddr); +/*! + * \brief Compare an ast_sockaddr to a pj_sockaddr + * + * \param addr pointer to ast_sockaddr structure + * \param pjaddr pointer to pj_sockaddr structure + * + * \retval -1 \a addr is lexicographically smaller than \a pjaddr + * \retval 0 \a addr is equal to \a pjaddr + * \retval 1 \a pjaddr is lexicographically smaller than \a addr +*/ +int ast_sockaddr_pj_sockaddr_cmp(const struct ast_sockaddr *addr, + const pj_sockaddr *pjaddr); + #endif /* _RES_PJPROJECT_H */ diff --git a/res/res_pjproject.c b/res/res_pjproject.c index 8eadaee82f6..865f06278fc 100644 --- a/res/res_pjproject.c +++ b/res/res_pjproject.c @@ -522,6 +522,7 @@ int ast_sockaddr_from_pj_sockaddr(struct ast_sockaddr *addr, const pj_sockaddr * sin->sin_addr.s_addr = pjaddr->ipv4.sin_addr.s_addr; #endif sin->sin_port = pjaddr->ipv4.sin_port; + memset(sin->sin_zero, 0, sizeof(sin->sin_zero)); addr->len = sizeof(struct sockaddr_in); } else if (pjaddr->addr.sa_family == pj_AF_INET6()) { struct sockaddr_in6 *sin = (struct sockaddr_in6 *) &addr->ss; @@ -538,6 +539,27 @@ int ast_sockaddr_from_pj_sockaddr(struct ast_sockaddr *addr, const pj_sockaddr * return 0; } +int ast_sockaddr_pj_sockaddr_cmp(const struct ast_sockaddr *addr, + const pj_sockaddr *pjaddr) +{ + struct ast_sockaddr temp_pjaddr; + int rc = 0; + + rc = ast_sockaddr_from_pj_sockaddr(&temp_pjaddr, pjaddr); + if (rc != 0) { + return -1; + } + + rc = ast_sockaddr_cmp(addr, &temp_pjaddr); + if (DEBUG_ATLEAST(4)) { + char *a_str = ast_strdupa(ast_sockaddr_stringify(addr)); + char *pj_str = ast_strdupa(ast_sockaddr_stringify(&temp_pjaddr)); + ast_debug(4, "Comparing %s -> %s rc: %d\n", a_str, pj_str, rc); + } + + return rc; +} + #ifdef TEST_FRAMEWORK static void fill_with_garbage(void *x, ssize_t len) { diff --git a/res/res_rtp_asterisk.c b/res/res_rtp_asterisk.c index 2341c846ff2..c8af3c37635 100644 --- a/res/res_rtp_asterisk.c +++ b/res/res_rtp_asterisk.c @@ -3214,11 +3214,10 @@ static int __rtp_recvfrom(struct ast_rtp_instance *instance, void *buf, size_t s * candidates list. */ +#ifdef HAVE_PJPROJECT if (rtp->ice) { int pass_src_check = 0; - struct ao2_iterator i; - struct ast_rtp_engine_ice_candidate *candidate; - int cand_cnt = 0; + int ix = 0; /* * You'd think that this check would cause a "deadlock" @@ -3239,20 +3238,18 @@ static int __rtp_recvfrom(struct ast_rtp_instance *instance, void *buf, size_t s } /* - * If we got this far, then ice_active_remote_candidates - * can't be NULL. + * If we got this far, then there have to be candidates. + * We have to use pjproject's rcands because they may have + * peer reflexive candidates that our ice_active_remote_candidates + * won't. */ - i = ao2_iterator_init(rtp->ice_active_remote_candidates, 0); - while ((candidate = ao2_iterator_next(&i)) && (cand_cnt < PJ_ICE_MAX_CAND)) { - res = ast_sockaddr_cmp_addr(&candidate->address, sa); - ao2_ref(candidate, -1); - if (res == 0) { + for (ix = 0; ix < rtp->ice->real_ice->rcand_cnt; ix++) { + pj_ice_sess_cand *rcand = &rtp->ice->real_ice->rcand[ix]; + if (ast_sockaddr_pj_sockaddr_cmp(sa, &rcand->addr) == 0) { pass_src_check = 1; break; } - cand_cnt++; } - ao2_iterator_destroy(&i); if (!pass_src_check) { ast_log(LOG_WARNING, "%s: DTLS packet from %s dropped. Source not in ICE active candidate list.\n", @@ -3261,6 +3258,7 @@ static int __rtp_recvfrom(struct ast_rtp_instance *instance, void *buf, size_t s return 0; } } +#endif /* * A race condition is prevented between dtls_perform_handshake()