chan_iax2: Several media format fixes.

* Fixed the iax.conf bandwidth option.  This is the root cause of
ASTERISK-24150.

* Added checks in iax2_request() to ensure that there are actual formats
requested for the new channel to prevent any more fracks from issues like
ASTERISK-24150.  This is a consequence of the iax.conf bandwidth option
not working.

* Fixed struct iax2_codec_pref.order member size mismatch issue when
converting to and from the codec preference order list passed over the
wire.  In addition the values sent over the wire are now compatible with
previous Asterisk versions.

* Fixed several issues dealing with the struct iax2_codec_pref members.
Off-by-one, array limit errors, and the order/framing members always need
to be updated together.

* Made iax2_request() setup the channel's native format preference order
according to the user's wishes.  The new media format strategy needs the
order specified earler.

* Fixed usage of ast_format_compatibility_bitfield2format().  The function
can return NULL if the bitfield was not associated with a function.

* Deleted dead code iax2_codec_pref_getsize() and
iax2_codec_pref_setsize().

* Made iax2_parse_allow_disallow() and iax2_codec_pref_string() call
iax2_codec_pref_to_cap() instead of inlining it.

* Made IAX_CAPABILITY_MEDBANDWIDTH, IAX_CAPABILITY_LOWBANDWIDTH, and
IAX_CAPABILITY_LOWFREE constants again as they were in Asterisk v1.8.

* Renamed prefs to prefs_global so it won't get confused with the local
pref versions.

* Fixed too small buffer in handle_cli_iax2_show_peer().

* Fixed ast_cli() calls in handle_cli_iax2_show_peer() to output complete
lines.

* Changed struct create_addr_info.prefs to be struct iax2_codec_pref as an
optimization so iax2_request() and iax2_call() do less work.

* Fixed a potential deadlock in ast_iax2_new() on an off-nominal path when
the pbx could not get started.

* Made set_config() setup a local prefs list along side the local
capability format bitfield.  Once the config is loaded, then the local
copies are put into the global versions.

* Fix unininialized codec_buf in function_iaxpeer().

ASTERISK-24150 #close
Reported by: Scott Griepentrog

Review: https://reviewboard.asterisk.org/r/3890/


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@420364 65c4cc65-6c06-0410-ace0-fbb531ad65f3

1 files changed, 123 insertions, 145 deletions

diff --git a/channels/chan_iax2.c b/channels/chan_iax2.c
index 831f2c266..630a66342 100644
--- a/channels/chan_iax2.c
+++ b/channels/chan_iax2.c
@@ -285,7 +285,7 @@ static int nochecksums = 0;
 /* Sample over last 100 units to determine historic jitter */
 #define GAMMA (0.01)
 
-static struct iax2_codec_pref prefs;
+static struct iax2_codec_pref prefs_global;
 
 static const char tdesc[] = "Inter Asterisk eXchange Driver (Ver 2)";
 
@@ -353,22 +353,22 @@ static int (*iax2_regfunk)(const char *username, int onoff) = NULL;
 #define IAX_CAPABILITY_FULLBANDWIDTH	0xFFFF
 /* T1, maybe ISDN */
 #define IAX_CAPABILITY_MEDBANDWIDTH (IAX_CAPABILITY_FULLBANDWIDTH & \
-                     ~ast_format_compatibility_format2bitfield(ast_format_slin) &      \
-                     ~ast_format_compatibility_format2bitfield(ast_format_slin16) &    \
-                     ~ast_format_compatibility_format2bitfield(ast_format_siren7) &       \
-                     ~ast_format_compatibility_format2bitfield(ast_format_siren14) &      \
-                     ~ast_format_compatibility_format2bitfield(ast_format_g719) &         \
-                     ~ast_format_compatibility_format2bitfield(ast_format_ulaw) &         \
-                     ~ast_format_compatibility_format2bitfield(ast_format_alaw) &         \
-                     ~ast_format_compatibility_format2bitfield(ast_format_g722))
+                     ~AST_FORMAT_SLIN &      \
+                     ~AST_FORMAT_SLIN16 &    \
+                     ~AST_FORMAT_SIREN7 &       \
+                     ~AST_FORMAT_SIREN14 &      \
+                     ~AST_FORMAT_G719 &         \
+                     ~AST_FORMAT_ULAW &         \
+                     ~AST_FORMAT_ALAW &         \
+                     ~AST_FORMAT_G722)
 /* A modem */
 #define IAX_CAPABILITY_LOWBANDWIDTH (IAX_CAPABILITY_MEDBANDWIDTH & \
-                     ~ast_format_compatibility_format2bitfield(ast_format_g726) &         \
-                     ~ast_format_compatibility_format2bitfield(ast_format_g726_aal2) &    \
-                     ~ast_format_compatibility_format2bitfield(ast_format_adpcm))
+                     ~AST_FORMAT_G726 &         \
+                     ~AST_FORMAT_G726_AAL2 &    \
+                     ~AST_FORMAT_ADPCM)
 
 #define IAX_CAPABILITY_LOWFREE      (IAX_CAPABILITY_LOWBANDWIDTH & \
-                     ~ast_format_compatibility_format2bitfield(ast_format_g723))
+                     ~AST_FORMAT_G723)
 
 
 #define DEFAULT_MAXMS		2000		/* Must be faster than 2 seconds by default */
@@ -1820,16 +1820,20 @@ static struct ast_format *codec_choose_from_prefs(struct iax2_codec_pref *pref,
 	int x;
 	struct ast_format *found_format = NULL;
 
-	for (x = 0; x < IAX2_CODEC_PREF_SIZE; x++) {
+	for (x = 0; x < ARRAY_LEN(pref->order); ++x) {
 		struct ast_format *pref_format;
-		uint64_t pref_as_bitfield = iax2_codec_pref_order_value_to_format_bitfield(pref->order[x]);
+		uint64_t pref_bitfield;
 
-		if (!pref_as_bitfield) {
+		pref_bitfield = iax2_codec_pref_order_value_to_format_bitfield(pref->order[x]);
+		if (!pref_bitfield) {
 			break;
 		}
 
-		pref_format = ast_format_compatibility_bitfield2format(pref_as_bitfield);
-
+		pref_format = ast_format_compatibility_bitfield2format(pref_bitfield);
+		if (!pref_format) {
+			/* The bitfield is not associated with any format. */
+			continue;
+		}
 		found_format = ast_format_cap_get_compatible_format(cap, pref_format);
 		if (found_format) {
 			break;
@@ -1867,61 +1871,6 @@ static iax2_format iax2_codec_choose(struct iax2_codec_pref *pref, iax2_format f
 	return format;
 }
 
-static iax2_format iax2_best_codec(iax2_format formats)
-{
-	/* This just our opinion, expressed in code.  We are asked to choose
-	   the best codec to use, given no information */
-	static const iax2_format prefs[] =
-	{
-		/*! Okay, ulaw is used by all telephony equipment, so start with it */
-		AST_FORMAT_ULAW,
-		/*! Unless of course, you're a silly European, so then prefer ALAW */
-		AST_FORMAT_ALAW,
-		AST_FORMAT_G719,
-		AST_FORMAT_SIREN14,
-		AST_FORMAT_SIREN7,
-		AST_FORMAT_TESTLAW,
-		/*! G.722 is better then all below, but not as common as the above... so give ulaw and alaw priority */
-		AST_FORMAT_G722,
-		/*! Okay, well, signed linear is easy to translate into other stuff */
-		AST_FORMAT_SLIN16,
-		AST_FORMAT_SLIN,
-		/*! G.726 is standard ADPCM, in RFC3551 packing order */
-		AST_FORMAT_G726,
-		/*! G.726 is standard ADPCM, in AAL2 packing order */
-		AST_FORMAT_G726_AAL2,
-		/*! ADPCM has great sound quality and is still pretty easy to translate */
-		AST_FORMAT_ADPCM,
-		/*! Okay, we're down to vocoders now, so pick GSM because it's small and easier to
-		    translate and sounds pretty good */
-		AST_FORMAT_GSM,
-		/*! iLBC is not too bad */
-		AST_FORMAT_ILBC,
-		/*! Speex is free, but computationally more expensive than GSM */
-		AST_FORMAT_SPEEX16,
-		AST_FORMAT_SPEEX,
-		/*! Opus */
-		AST_FORMAT_OPUS,
-		/*! Ick, LPC10 sounds terrible, but at least we have code for it, if you're tacky enough
-		    to use it */
-		AST_FORMAT_LPC10,
-		/*! G.729a is faster than 723 and slightly less expensive */
-		AST_FORMAT_G729,
-		/*! Down to G.723.1 which is proprietary but at least designed for voice */
-		AST_FORMAT_G723,
-	};
-	int x;
-
-	/* Find the first preferred codec in the format given */
-	for (x = 0; x < ARRAY_LEN(prefs); x++) {
-		if (formats & prefs[x]) {
-			return prefs[x];
-		}
-	}
-
-	return 0;
-}
-
 const char *iax2_getformatname(iax2_format format)
 {
 	struct ast_format *tmpfmt;
@@ -1951,33 +1900,24 @@ static const char *iax2_getformatname_multiple(iax2_format format, struct ast_st
 static int iax2_parse_allow_disallow(struct iax2_codec_pref *pref, iax2_format *formats, const char *list, int allowing)
 {
 	int res, i;
-	struct ast_format_cap *cap = ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_DEFAULT);
-
-	if (!cap) {
-		return 1;
-	}
+	struct ast_format_cap *cap;
 
 	/* We want to add the formats to the cap in the preferred order */
-	for (i = 0; i < IAX2_CODEC_PREF_SIZE; i++) {
-		uint64_t pref_as_bitfield = iax2_codec_pref_order_value_to_format_bitfield(pref->order[i]);
-
-		if (!pref_as_bitfield) {
-			break;
-		}
-
-		if (iax2_format_compatibility_bitfield2cap(pref_as_bitfield, cap)) {
-			ao2_ref(cap, -1);
-			return 1;
-		}
+	cap = ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_DEFAULT);
+	if (!cap || iax2_codec_pref_to_cap(pref, cap)) {
+		ao2_cleanup(cap);
+		return 1;
 	}
 
 	res = ast_format_cap_update_by_allow_disallow(cap, list, allowing);
-	*formats = iax2_format_compatibility_cap2bitfield(cap);
 
+	/* Adjust formats bitfield and pref list to match. */
+	*formats = iax2_format_compatibility_cap2bitfield(cap);
 	iax2_codec_pref_remove_missing(pref, *formats);
 
 	for (i = 0; i < ast_format_cap_count(cap); i++) {
 		struct ast_format *fmt = ast_format_cap_get_format(cap, i);
+
 		iax2_codec_pref_append(pref, fmt, ast_format_cap_get_format_framing(cap, fmt));
 		ao2_ref(fmt, -1);
 	}
@@ -2283,7 +2223,7 @@ static struct chan_iax2_pvt *new_iax(struct ast_sockaddr *addr, const char *host
 		return NULL;
 	}
 
-	tmp->prefs = prefs;
+	tmp->prefs = prefs_global;
 	tmp->pingid = -1;
 	tmp->lagid = -1;
 	tmp->autoid = -1;
@@ -3844,7 +3784,7 @@ static char *handle_cli_iax2_show_peer(struct ast_cli_entry *e, int cmd, struct
 	char status[30];
 	char cbuf[256];
 	struct iax2_peer *peer;
-	struct ast_str *codec_buf = ast_str_alloca(64);
+	struct ast_str *codec_buf = ast_str_alloca(256);
 	struct ast_str *encmethods = ast_str_alloca(256);
 	int load_realtime = 0;
 
@@ -3895,17 +3835,15 @@ static char *handle_cli_iax2_show_peer(struct ast_cli_entry *e, int cmd, struct
 		ast_cli(a->fd, "  Addr->IP     : %s Port %s\n",  str_addr ? str_addr : "(Unspecified)", str_port);
 		ast_cli(a->fd, "  Defaddr->IP  : %s Port %s\n", str_defaddr, str_defport);
 		ast_cli(a->fd, "  Username     : %s\n", peer->username);
-		ast_cli(a->fd, "  Codecs       : ");
-		ast_cli(a->fd, "%s\n", iax2_getformatname_multiple(peer->capability, &codec_buf));
+		ast_cli(a->fd, "  Codecs       : %s\n", iax2_getformatname_multiple(peer->capability, &codec_buf));
 
-		ast_cli(a->fd, "  Codec Order  : ");
-		if (iax2_codec_pref_string(&peer->prefs, cbuf, sizeof(cbuf)) != -1) {
-			ast_cli(a->fd, "%s\n", cbuf);
+		if (iax2_codec_pref_string(&peer->prefs, cbuf, sizeof(cbuf)) < 0) {
+			strcpy(cbuf, "Error"); /* Safe */
 		}
+		ast_cli(a->fd, "  Codec Order  : %s\n", cbuf);
 
-		ast_cli(a->fd, "  Status       : ");
 		peer_status(peer, status, sizeof(status));
-		ast_cli(a->fd, "%s\n",status);
+		ast_cli(a->fd, "  Status       : %s\n", status);
 		ast_cli(a->fd, "  Qualify      : every %dms when OK, every %dms when UNREACHABLE (sample smoothing %s)\n", peer->pokefreqok, peer->pokefreqnotok, peer->smoothing ? "On" : "Off");
 		ast_cli(a->fd, "\n");
 		peer_unref(peer);
@@ -4654,6 +4592,7 @@ static void realtime_update_peer(const char *peername, struct ast_sockaddr *sock
 struct create_addr_info {
 	iax2_format capability;
 	uint64_t flags;
+	struct iax2_codec_pref prefs;
 	int maxtime;
 	int encmethods;
 	int found;
@@ -4663,7 +4602,6 @@ struct create_addr_info {
 	char secret[80];
 	char outkey[80];
 	char timezone[80];
-	char prefs[32];
 	char cid_num[80];
 	char cid_name[80];
 	char context[AST_MAX_CONTEXT];
@@ -4676,7 +4614,6 @@ static int create_addr(const char *peername, struct ast_channel *c, struct ast_s
 {
 	struct iax2_peer *peer;
 	int res = -1;
-	struct iax2_codec_pref ourprefs;
 
 	ast_clear_flag64(cai, IAX_SENDANI | IAX_TRUNK);
 	cai->sockfd = defaultsockfd;
@@ -4697,20 +4634,24 @@ static int create_addr(const char *peername, struct ast_channel *c, struct ast_s
 		}
 
 		ast_sockaddr_copy(addr, &peer_addr);
-		/* use global iax prefs for unknown peer/user */
-		/* But move the calling channel's native codec to the top of the preference list */
-		memcpy(&ourprefs, &prefs, sizeof(ourprefs));
+		/*
+		 * Use The global iax prefs for unknown peer/user.
+		 * However, move the calling channel's native codec to
+		 * the top of the preference list.
+		 */
+		cai->prefs = prefs_global;
 		if (c) {
 			int i;
 
 			for (i = 0; i < ast_format_cap_count(ast_channel_nativeformats(c)); i++) {
 				struct ast_format *format = ast_format_cap_get_format(
 					ast_channel_nativeformats(c), i);
-				iax2_codec_pref_prepend(&ourprefs, format, ast_format_cap_get_format_framing(ast_channel_nativeformats(c), format), 1);
+				iax2_codec_pref_prepend(&cai->prefs, format,
+					ast_format_cap_get_format_framing(ast_channel_nativeformats(c), format),
+					1);
 				ao2_ref(format, -1);
 			}
 		}
-		iax2_codec_pref_convert(&ourprefs, cai->prefs, sizeof(cai->prefs), 1);
 		return 0;
 	}
 
@@ -4731,7 +4672,7 @@ static int create_addr(const char *peername, struct ast_channel *c, struct ast_s
 	cai->encmethods = peer->encmethods;
 	cai->sockfd = peer->sockfd;
 	cai->adsi = peer->adsi;
-	memcpy(&ourprefs, &peer->prefs, sizeof(ourprefs));
+	cai->prefs = peer->prefs;
 	/* Move the calling channel's native codec to the top of the preference list */
 	if (c) {
 		int i;
@@ -4739,11 +4680,12 @@ static int create_addr(const char *peername, struct ast_channel *c, struct ast_s
 		for (i = 0; i < ast_format_cap_count(ast_channel_nativeformats(c)); i++) {
 			struct ast_format *tmpfmt = ast_format_cap_get_format(
 				ast_channel_nativeformats(c), i);
-			iax2_codec_pref_prepend(&ourprefs, tmpfmt, ast_format_cap_get_format_framing(ast_channel_nativeformats(c), tmpfmt), 1);
+			iax2_codec_pref_prepend(&cai->prefs, tmpfmt,
+				ast_format_cap_get_format_framing(ast_channel_nativeformats(c), tmpfmt),
+				1);
 			ao2_ref(tmpfmt, -1);
 		}
 	}
-	iax2_codec_pref_convert(&ourprefs, cai->prefs, sizeof(cai->prefs), 1);
 	ast_copy_string(cai->context, peer->context, sizeof(cai->context));
 	ast_copy_string(cai->peercontext, peer->peercontext, sizeof(cai->peercontext));
 	ast_copy_string(cai->username, peer->username, sizeof(cai->username));
@@ -5150,6 +5092,7 @@ static int iax2_call(struct ast_channel *c, const char *dest, int timeout)
 	unsigned char osp_block_index;
 	unsigned int osp_block_length;
 	unsigned char osp_buffer[256];
+	char encoded_prefs[32];
 	iax2_format iax2_tmpfmt;
 
 	if ((ast_channel_state(c) != AST_STATE_DOWN) && (ast_channel_state(c) != AST_STATE_RESERVED)) {
@@ -5218,7 +5161,8 @@ static int iax2_call(struct ast_channel *c, const char *dest, int timeout)
 	}
 
 	/* WARNING: this breaks down at 190 bits! */
-	iax_ie_append_str(&ied, IAX_IE_CODEC_PREFS, cai.prefs);
+	iax2_codec_pref_convert(&cai.prefs, encoded_prefs, sizeof(encoded_prefs), 1);
+	iax_ie_append_str(&ied, IAX_IE_CODEC_PREFS, encoded_prefs);
 
 	if (l) {
 		iax_ie_append_str(&ied, IAX_IE_CALLING_NUMBER, l);
@@ -5877,7 +5821,9 @@ static int iax2_getpeertrunk(struct ast_sockaddr addr)
 }
 
 /*! \brief  Create new call, interface with the PBX core */
-static struct ast_channel *ast_iax2_new(int callno, int state, iax2_format capability, const struct ast_assigned_ids *assignedids, const struct ast_channel *requestor, unsigned int cachable)
+static struct ast_channel *ast_iax2_new(int callno, int state, iax2_format capability,
+	struct iax2_codec_pref *prefs, const struct ast_assigned_ids *assignedids,
+	const struct ast_channel *requestor, unsigned int cachable)
 {
 	struct ast_channel *tmp = NULL;
 	struct chan_iax2_pvt *i;
@@ -5893,10 +5839,22 @@ static struct ast_channel *ast_iax2_new(int callno, int state, iax2_format capab
 		return NULL;
 	}
 
+	if (!capability) {
+		ast_log(LOG_WARNING, "No formats specified for call to: IAX2/%s-%d\n",
+			i->host, i->callno);
+		return NULL;
+	}
 	native = ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_DEFAULT);
 	if (!native) {
 		return NULL;
 	}
+	if (iax2_codec_pref_best_bitfield2cap(capability, prefs, native)
+		|| !ast_format_cap_count(native)) {
+		ast_log(LOG_WARNING, "No requested formats available for call to: IAX2/%s-%d\n",
+			i->host, i->callno);
+		ao2_ref(native, -1);
+		return NULL;
+	}
 
 	if (!ast_strlen_zero(i->peer)) {
 		peer_name = ast_strdupa(i->peer);
@@ -5910,13 +5868,17 @@ static struct ast_channel *ast_iax2_new(int callno, int state, iax2_format capab
 	if (!ast_strlen_zero(peer_name)) {
 		peer = find_peer(peer_name, 1);
 		if (peer && peer->endpoint) {
-			tmp = ast_channel_alloc_with_endpoint(1, state, i->cid_num, i->cid_name, i->accountcode, i->exten, i->context, assignedids, requestor, i->amaflags, peer->endpoint, "IAX2/%s-%d", i->host, i->callno);
+			tmp = ast_channel_alloc_with_endpoint(1, state, i->cid_num, i->cid_name,
+				i->accountcode, i->exten, i->context, assignedids, requestor,
+				i->amaflags, peer->endpoint, "IAX2/%s-%d", i->host, i->callno);
 		}
 		ao2_cleanup(peer);
 	}
 
 	if (!tmp) {
-		tmp = ast_channel_alloc(1, state, i->cid_num, i->cid_name, i->accountcode, i->exten, i->context, assignedids, requestor, i->amaflags, "IAX2/%s-%d", i->host, i->callno);
+		tmp = ast_channel_alloc(1, state, i->cid_num, i->cid_name, i->accountcode,
+			i->exten, i->context, assignedids, requestor, i->amaflags, "IAX2/%s-%d",
+			i->host, i->callno);
 	}
 
 	ast_mutex_lock(&iaxsl[callno]);
@@ -5945,9 +5907,8 @@ static struct ast_channel *ast_iax2_new(int callno, int state, iax2_format capab
 	ast_channel_tech_set(tmp, &iax2_tech);
 
 	/* We can support any format by default, until we get restricted */
-	iax2_format_compatibility_bitfield2cap(capability, native);
 	ast_channel_nativeformats_set(tmp, native);
-	tmpfmt = ast_format_cap_get_format(ast_channel_nativeformats(tmp), 0);
+	tmpfmt = ast_format_cap_get_format(native, 0);
 
 	ast_channel_set_readformat(tmp, tmpfmt);
 	ast_channel_set_rawreadformat(tmp, tmpfmt);
@@ -6046,8 +6007,10 @@ static struct ast_channel *ast_iax2_new(int callno, int state, iax2_format capab
 	if (state != AST_STATE_DOWN) {
 		if (ast_pbx_start(tmp)) {
 			ast_log(LOG_WARNING, "Unable to start PBX on %s\n", ast_channel_name(tmp));
+			/* unlock and relock iaxsl[callno] to preserve locking order */
+			ast_mutex_unlock(&iaxsl[callno]);
 			ast_hangup(tmp);
-			i->owner = NULL;
+			ast_mutex_lock(&iaxsl[callno]);
 			return NULL;
 		}
 	}
@@ -7907,8 +7870,10 @@ static int check_access(int callno, struct ast_sockaddr *addr, struct iax_ies *i
 	/* Use provided preferences until told otherwise for actual preferences */
 	if (ies->codec_prefs) {
 		iax2_codec_pref_convert(&iaxs[callno]->rprefs, ies->codec_prefs, 32, 0);
-		iax2_codec_pref_convert(&iaxs[callno]->prefs, ies->codec_prefs, 32, 0);
+	} else {
+		memset(&iaxs[callno]->rprefs, 0, sizeof(iaxs[callno]->rprefs));
 	}
+	iaxs[callno]->prefs = iaxs[callno]->rprefs;
 
 	if (!gotcapability) {
 		iaxs[callno]->peercapability = iaxs[callno]->peerformat;
@@ -10556,8 +10521,9 @@ static int socket_process_helper(struct iax2_thread *thread)
 		    (f.frametype == AST_FRAME_IAX)) {
 			if (ast_test_flag64(iaxs[fr->callno], IAX_DELAYPBXSTART)) {
 				ast_clear_flag64(iaxs[fr->callno], IAX_DELAYPBXSTART);
-				if (!ast_iax2_new(fr->callno, AST_STATE_RING, iaxs[fr->callno]->chosenformat, NULL, NULL,
-						  ast_test_flag(&iaxs[fr->callno]->state, IAX_STATE_AUTHENTICATED))) {
+				if (!ast_iax2_new(fr->callno, AST_STATE_RING,
+					iaxs[fr->callno]->chosenformat, &iaxs[fr->callno]->rprefs, NULL, NULL,
+					ast_test_flag(&iaxs[fr->callno]->state, IAX_STATE_AUTHENTICATED))) {
 					ast_variables_destroy(ies.vars);
 					ast_mutex_unlock(&iaxsl[fr->callno]);
 					return 1;
@@ -10893,7 +10859,7 @@ static int socket_process_helper(struct iax2_thread *thread)
 									if(ast_test_flag64(iaxs[fr->callno], IAX_CODEC_NOPREFS)) {
 										using_prefs = ast_test_flag64(iaxs[fr->callno], IAX_CODEC_NOCAP) ? "reqonly" : "disabled";
 										memset(&pref, 0, sizeof(pref));
-										format = iax2_best_codec(iaxs[fr->callno]->peercapability & iaxs[fr->callno]->capability);
+										format = iax2_format_compatibility_best(iaxs[fr->callno]->peercapability & iaxs[fr->callno]->capability);
 										strcpy(caller_pref_buf,"disabled");
 										strcpy(host_pref_buf,"disabled");
 									} else {
@@ -10909,7 +10875,7 @@ static int socket_process_helper(struct iax2_thread *thread)
 											}
 											format = iax2_codec_choose(&pref, iaxs[fr->callno]->peercapability & iaxs[fr->callno]->capability);
 										} else /* if no codec_prefs IE do it the old way */
-											format = iax2_best_codec(iaxs[fr->callno]->peercapability & iaxs[fr->callno]->capability);
+											format = iax2_format_compatibility_best(iaxs[fr->callno]->peercapability & iaxs[fr->callno]->capability);
 									}
 								}
 
@@ -11111,7 +11077,9 @@ static int socket_process_helper(struct iax2_thread *thread)
 						struct ast_str *cap_buf = ast_str_alloca(64);
 
 						/* Switch us to use a compatible format */
-						iax2_format_compatibility_bitfield2cap(iaxs[fr->callno]->peerformat, native);
+						iax2_codec_pref_best_bitfield2cap(
+							iaxs[fr->callno]->peerformat, &iaxs[fr->callno]->rprefs,
+							native);
 						ast_channel_nativeformats_set(iaxs[fr->callno]->owner, native);
 						ast_verb(3, "Format for call is %s\n", ast_format_cap_get_names(ast_channel_nativeformats(iaxs[fr->callno]->owner), &cap_buf));
 
@@ -11351,8 +11319,9 @@ static int socket_process_helper(struct iax2_thread *thread)
 								if(ast_test_flag64(iaxs[fr->callno], IAX_CODEC_NOPREFS)) {
 									using_prefs = ast_test_flag64(iaxs[fr->callno], IAX_CODEC_NOCAP) ? "reqonly" : "disabled";
 									memset(&pref, 0, sizeof(pref));
-									format = ast_test_flag64(iaxs[fr->callno], IAX_CODEC_NOCAP) ?
-										iaxs[fr->callno]->peerformat : iax2_best_codec(iaxs[fr->callno]->peercapability & iaxs[fr->callno]->capability);
+									format = ast_test_flag64(iaxs[fr->callno], IAX_CODEC_NOCAP)
+										? iaxs[fr->callno]->peerformat
+										: iax2_format_compatibility_best(iaxs[fr->callno]->peercapability & iaxs[fr->callno]->capability);
 									strcpy(caller_pref_buf,"disabled");
 									strcpy(host_pref_buf,"disabled");
 								} else {
@@ -11368,7 +11337,7 @@ static int socket_process_helper(struct iax2_thread *thread)
 										}
 										format = iax2_codec_choose(&pref, iaxs[fr->callno]->peercapability & iaxs[fr->callno]->capability);
 									} else /* if no codec_prefs IE do it the old way */
-										format = iax2_best_codec(iaxs[fr->callno]->peercapability & iaxs[fr->callno]->capability);
+										format = iax2_format_compatibility_best(iaxs[fr->callno]->peercapability & iaxs[fr->callno]->capability);
 								}
 							}
 							if (!format) {
@@ -11429,9 +11398,11 @@ static int socket_process_helper(struct iax2_thread *thread)
 											using_prefs);
 
 							ast_set_flag(&iaxs[fr->callno]->state, IAX_STATE_STARTED);
-							if (!(c = ast_iax2_new(fr->callno, AST_STATE_RING, format, NULL, NULL, 1)))
+							c = ast_iax2_new(fr->callno, AST_STATE_RING, format,
+								&iaxs[fr->callno]->rprefs, NULL, NULL, 1);
+							if (!c) {
 								iax2_destroy(fr->callno);
-							else if (ies.vars) {
+							} else if (ies.vars) {
 								struct ast_datastore *variablestore;
 								struct ast_variable *var, *prev = NULL;
 								AST_LIST_HEAD(, ast_var_t) *varlist;
@@ -11503,9 +11474,12 @@ immediatedial:
 								iax2_getformatname_multiple(iaxs[fr->callno]->peerformat, &cap_buf));
 						ast_set_flag(&iaxs[fr->callno]->state, IAX_STATE_STARTED);
 						send_command(iaxs[fr->callno], AST_FRAME_CONTROL, AST_CONTROL_PROGRESS, 0, NULL, 0, -1);
-						if (!(c = ast_iax2_new(fr->callno, AST_STATE_RING, iaxs[fr->callno]->peerformat, NULL, NULL, 1)))
+						c = ast_iax2_new(fr->callno, AST_STATE_RING,
+							iaxs[fr->callno]->peerformat, &iaxs[fr->callno]->rprefs,
+							NULL, NULL, 1);
+						if (!c) {
 							iax2_destroy(fr->callno);
-						else if (ies.vars) {
+						} else if (ies.vars) {
 							struct ast_datastore *variablestore;
 							struct ast_variable *var, *prev = NULL;
 							AST_LIST_HEAD(, ast_var_t) *varlist;
@@ -12528,7 +12502,8 @@ static struct ast_channel *iax2_request(const char *type, struct ast_format_cap
 		ast_string_field_set(iaxs[callno], host, pds.peer);
 	}
 
-	c = ast_iax2_new(callno, AST_STATE_DOWN, cai.capability, assignedids, requestor, cai.found);
+	c = ast_iax2_new(callno, AST_STATE_DOWN, cai.capability, &cai.prefs, assignedids,
+		requestor, cai.found);
 
 	ast_mutex_unlock(&iaxsl[callno]);
 
@@ -12840,7 +12815,7 @@ static struct iax2_peer *build_peer(const char *name, struct ast_variable *v, st
 				ast_sockaddr_set_port(&peer->addr, IAX_DEFAULT_PORTNO);
 				peer->expiry = min_reg_expire;
 			}
-			peer->prefs = prefs;
+			peer->prefs = prefs_global;
 			peer->capability = iax2_capability;
 			peer->smoothing = 0;
 			peer->pokefreqok = DEFAULT_FREQ_OK;
@@ -13157,7 +13132,7 @@ static struct iax2_user *build_user(const char *name, struct ast_variable *v, st
 			}
 			user->maxauthreq = maxauthreq;
 			user->curauthreq = oldcurauthreq;
-			user->prefs = prefs;
+			user->prefs = prefs_global;
 			user->capability = iax2_capability;
 			user->encmethods = iax2_encryption;
 			user->adsi = adsi;
@@ -13470,7 +13445,7 @@ static void set_config_destroy(void)
 static int set_config(const char *config_file, int reload, int forced)
 {
 	struct ast_config *cfg, *ucfg;
-	iax2_format capability = iax2_capability;
+	iax2_format capability;
 	struct ast_variable *v;
 	char *cat;
 	const char *utype;
@@ -13485,9 +13460,7 @@ static int set_config(const char *config_file, int reload, int forced)
 	struct ast_netsock *ns;
 	struct ast_flags config_flags = { (reload && !forced) ? CONFIG_FLAG_FILEUNCHANGED : 0 };
 	struct ast_sockaddr bindaddr;
-#if 0
-	static unsigned short int last_port=0;
-#endif
+	struct iax2_codec_pref prefs_new;
 
 	cfg = ast_config_load(config_file, config_flags);
 
@@ -13528,8 +13501,8 @@ static int set_config(const char *config_file, int reload, int forced)
 
 	ast_sockaddr_parse(&bindaddr, "0.0.0.0:0", 0);
 
-	/* Reset global codec prefs */
-	memset(&prefs, 0 , sizeof(struct iax2_codec_pref));
+	/* Setup new codec prefs */
+	capability = iax2_codec_pref_from_bitfield(&prefs_new, IAX_CAPABILITY_FULLBANDWIDTH);
 
 	/* Reset Global Flags */
 	memset(&globalflags, 0, sizeof(globalflags));
@@ -13754,17 +13727,21 @@ static int set_config(const char *config_file, int reload, int forced)
 			}
 		} else if (!strcasecmp(v->name, "bandwidth")) {
 			if (!strcasecmp(v->value, "low")) {
-				capability = IAX_CAPABILITY_LOWBANDWIDTH;
+				capability = iax2_codec_pref_from_bitfield(&prefs_new,
+					IAX_CAPABILITY_LOWBANDWIDTH);
 			} else if (!strcasecmp(v->value, "medium")) {
-				capability = IAX_CAPABILITY_MEDBANDWIDTH;
+				capability = iax2_codec_pref_from_bitfield(&prefs_new,
+					IAX_CAPABILITY_MEDBANDWIDTH);
 			} else if (!strcasecmp(v->value, "high")) {
-				capability = IAX_CAPABILITY_FULLBANDWIDTH;
-			} else
+				capability = iax2_codec_pref_from_bitfield(&prefs_new,
+					IAX_CAPABILITY_FULLBANDWIDTH);
+			} else {
 				ast_log(LOG_WARNING, "bandwidth must be either low, medium, or high\n");
+			}
 		} else if (!strcasecmp(v->name, "allow")) {
-			iax2_parse_allow_disallow(&prefs, &capability, v->value, 1);
+			iax2_parse_allow_disallow(&prefs_new, &capability, v->value, 1);
 		} else if (!strcasecmp(v->name, "disallow")) {
-			iax2_parse_allow_disallow(&prefs, &capability, v->value, 0);
+			iax2_parse_allow_disallow(&prefs_new, &capability, v->value, 0);
 		} else if (!strcasecmp(v->name, "register")) {
 			iax2_register(v->value, v->lineno);
 		} else if (!strcasecmp(v->name, "iaxcompat")) {
@@ -13882,6 +13859,7 @@ static int set_config(const char *config_file, int reload, int forced)
 			min_reg_expire, max_reg_expire, max_reg_expire);
 		min_reg_expire = max_reg_expire;
 	}
+	prefs_global = prefs_new;
 	iax2_capability = capability;
 
 	if (ucfg) {
@@ -14408,7 +14386,7 @@ static int function_iaxpeer(struct ast_channel *chan, const char *cmd, char *dat
 	} else  if (!strcasecmp(colname, "callerid_num")) {
 		ast_copy_string(buf, peer->cid_num, len);
 	} else  if (!strcasecmp(colname, "codecs")) {
-		struct ast_str *codec_buf;
+		struct ast_str *codec_buf = ast_str_alloca(256);
 
 		iax2_getformatname_multiple(peer->capability, &codec_buf);
 		ast_copy_string(buf, ast_str_buffer(codec_buf), len);