channels/chan_sip: Support mutltiple Supported and Required headers

A SIP request may contain multiple Supported: and Required: headers. Currently,
chan_sip only parses the first Supported/Required header it finds. This patch
adds support for multiple Supported/Required headers for INVITE requests.

Review: https://reviewboard.asterisk.org/r/2478

ASTERISK-21721 #close
Reported by: Olle Johansson
patches:
  rb2478.patch uploaded by oej (License 5267)
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Merged revisions 426594 from http://svn.asterisk.org/svn/asterisk/branches/1.8
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Merged revisions 426595 from http://svn.asterisk.org/svn/asterisk/branches/11
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Merged revisions 426596 from http://svn.asterisk.org/svn/asterisk/branches/12


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/13@426597 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_sip.c

@@ -25071,7 +25071,9 @@ static int handle_request_invite(struct sip_pvt *p, struct sip_request *req, str
 	int reinvite = 0;
 	struct ast_party_redirecting redirecting;
 	struct ast_set_party_redirecting update_redirecting;
-
+	int supported_start = 0;
+	int require_start = 0;
+	char unsupported[256] = { 0, };
 	struct {
 		char exten[AST_MAX_EXTENSION];
 		char context[AST_MAX_CONTEXT];
@@ -25083,31 +25085,37 @@ static int handle_request_invite(struct sip_pvt *p, struct sip_request *req, str
 
 	/* Find out what they support */
 	if (!p->sipoptions) {
-		const char *supported = sip_get_header(req, "Supported");
-		if (!ast_strlen_zero(supported)) {
-			p->sipoptions = parse_sip_options(supported, NULL, 0);
-		}
+		const char *supported = NULL;
+		do {
+			supported = __get_header(req, "Supported", &supported_start);
+			if (!ast_strlen_zero(supported)) {
+				p->sipoptions |= parse_sip_options(supported, NULL, 0);
+			}
+		} while (!ast_strlen_zero(supported));
 	}
 
 	/* Find out what they require */
-	required = sip_get_header(req, "Require");
-	if (!ast_strlen_zero(required)) {
-		char unsupported[256] = { 0, };
-		required_profile = parse_sip_options(required, unsupported, ARRAY_LEN(unsupported));
-
-		/* If there are any options required that we do not support,
-		 * then send a 420 with only those unsupported options listed */
-		if (!ast_strlen_zero(unsupported)) {
-			transmit_response_with_unsupported(p, "420 Bad extension (unsupported)", req, unsupported);
-			ast_log(LOG_WARNING, "Received SIP INVITE with unsupported required extension: required:%s unsupported:%s\n", required, unsupported);
-			p->invitestate = INV_COMPLETED;
-			if (!p->lastinvite)
-				sip_scheddestroy(p, DEFAULT_TRANS_TIMEOUT);
-			res = INV_REQ_ERROR;
-			goto request_invite_cleanup;
+	do {
+		required = __get_header(req, "Require", &require_start);
+		if (!ast_strlen_zero(required)) {
+			required_profile |= parse_sip_options(required, unsupported, ARRAY_LEN(unsupported));
+		}
+	} while (!ast_strlen_zero(required));
+
+	/* If there are any options required that we do not support,
+	 * then send a 420 with only those unsupported options listed */
+	if (!ast_strlen_zero(unsupported)) {
+		transmit_response_with_unsupported(p, "420 Bad extension (unsupported)", req, unsupported);
+		ast_log(LOG_WARNING, "Received SIP INVITE with unsupported required extension: required:%s unsupported:%s\n", required, unsupported);
+		p->invitestate = INV_COMPLETED;
+		if (!p->lastinvite) {
+			sip_scheddestroy(p, DEFAULT_TRANS_TIMEOUT);
 		}
+		res = -1;
+		goto request_invite_cleanup;
 	}
 
+
 	/* The option tags may be present in Supported: or Require: headers.
 	Include the Require: option tags for further processing as well */
 	p->sipoptions |= required_profile;

channels/sip/reqresp_parser.c

@@ -1692,10 +1692,6 @@ unsigned int parse_sip_options(const char *options, char *unsupported, size_t un
 	size_t outlen = unsupported_len;
 	char *cur_out = out;
 
-	if (out && (outlen > 0)) {
-		memset(out, 0, outlen);
-	}
-
 	if (ast_strlen_zero(options) )
 		return 0;