Fix function get_local_contact() to add transport

to have consistency over b2b and presence module, fix the get_local_contact() to also add the transport indication in the URI it builds. This will simplify the code in presence (as we do not have to add the transport param later, from several parts of the code) and also fixes the b2b code where the transport was not added at all in the URIs.

Credits go to @arttemk for identifing the problem and suggesting the fix.
Fix for  #1275

modules/presence/doc/presence_admin.xml

@@ -300,13 +300,17 @@ modparam("presence", "max_expires_publish", 3600)
 <section id="param_server_address" xreflabel="server_address">
 		<title><varname>server_address</varname> (str)</title>
 		<para>
-		The optional presence server address which will become the value of 
+		The optional presence server URI address which will become the value of
 		Contact header filed for 200OK replies to Subscribe and Publish 
 		and in Notify messages.
 		</para>
 		<para>
-		If not set (as it is by default), OpenSIPS will generate the Conact URI
-		based on the interface it received the SIP traffic.
+		NOTE: this must be a fully formated SIP URI, with port and transport
+		parameter if the case.
+		</para>
+		<para>
+		If not set (as it is by default), OpenSIPS will generate the Contact 
+		URI based on the interface it received the SIP traffic.
 		</para>
 		<example>
 		<title>Set <varname>server_address</varname> parameter</title>

modules/presence/notify.c

@@ -148,10 +148,10 @@ int build_str_hdr(subs_t* subs, int is_body, str* hdr, str* extra_hdrs)
 	}
 	status.len = strlen(status.s);
 
-	len = 7 /*Event: */ + subs->event->name.len +4 /*;id=*/+ subs->event_id.len+
-		CRLF_LEN + 10 /*Contact: <*/ + subs->local_contact.len + 1/*>*/ +
-		((subs->sockinfo && subs->sockinfo->proto!=PROTO_UDP)?
-		 15/*";transport=xxxx"*/:0) + CRLF_LEN + 20 /*Subscription-State: */ +
+	len = 7 /*Event: */ + subs->event->name.len + 4 /*;id=*/ +
+		subs->event_id.len + CRLF_LEN +
+		10 /*Contact: <*/ + subs->local_contact.len + 1/*>*/ + CRLF_LEN +
+		20 /*Subscription-State: */ +
 		status.len + ((subs->status== TERMINATED_STATUS)?(10/*;reason=*/+
 		subs->reason.len):9/*expires=*/ + lexpire_len) + CRLF_LEN + (is_body?
 		(14 /*Content-Type: */+subs->event->content_type.len + CRLF_LEN):0);
@@ -185,33 +185,14 @@ int build_str_hdr(subs_t* subs, int is_body, str* hdr, str* extra_hdrs)
  		memcpy(p, subs->event_id.s, subs->event_id.len);
  		p += subs->event_id.len;
  	}
-	memcpy(p, CRLF, CRLF_LEN);
-	p += CRLF_LEN;
 
-	memcpy(p ,"Contact: <", 10);
-	p += 10;
+	memcpy(p ,CRLF "Contact: <", CRLF_LEN+10);
+	p += CRLF_LEN+10;
 	memcpy(p, subs->local_contact.s, subs->local_contact.len);
 	p +=  subs->local_contact.len;
 
-	if (subs->sockinfo && subs->sockinfo->proto!=PROTO_UDP)
-	{
-		memcpy(p,";transport=",11);
-		p += 11;
-		p = proto2str(subs->sockinfo->proto, p);
-		if (p == NULL)
-		{
-			LM_ERR("invalid proto\n");
-			pkg_free(hdr->s);
-			return -1;
-		}
-	}
-	*(p++) = '>';
-
-	memcpy(p, CRLF, CRLF_LEN);
-	p += CRLF_LEN;
-
-	memcpy(p, "Subscription-State: ", 20);
-	p+= 20;
+	memcpy(p, ">" CRLF "Subscription-State: " , 1+CRLF_LEN+20);
+	p += 1+CRLF_LEN+20;
 
 	memcpy(p, status.s, status.len);
 	p += status.len;

modules/presence/subscribe.c

@@ -70,9 +70,7 @@ int send_2XX_reply(struct sip_msg * msg, int reply_code, int lexpire,
 	lexpire_s = int2str((unsigned long)lexpire, &lexpire_len);
 
 	len = 9 /*"Expires: "*/ + lexpire_len + CRLF_LEN
-		+ 10 /*"Contact: <"*/ + local_contact->len + 1 /*">"*/
-		+ ((msg->rcv.proto!=PROTO_UDP)?15/*";transport=xxxx"*/:0)
-		+ CRLF_LEN;
+		+ 10 /*"Contact: <"*/ + local_contact->len + 1 /*">"*/ + CRLF_LEN;
 
 	hdr_append = (char *)pkg_malloc( len );
 	if(hdr_append == NULL)
@@ -86,25 +84,13 @@ int send_2XX_reply(struct sip_msg * msg, int reply_code, int lexpire,
 	p += 9;
 	memcpy(p,lexpire_s,lexpire_len);
 	p += lexpire_len;
-	memcpy(p,CRLF,CRLF_LEN);
-	p += CRLF_LEN;
 	/* contact header */
-	memcpy(p,"Contact: <", 10);
-	p += 10;
+	memcpy(p, CRLF "Contact: <", CRLF_LEN+10);
+	p += CRLF_LEN + 10;
 	memcpy(p,local_contact->s,local_contact->len);
 	p += local_contact->len;
-	if (msg->rcv.proto!=PROTO_UDP) {
-		memcpy(p,";transport=",11);
-		p += 11;
-		p = proto2str(msg->rcv.proto, p);
-		if (p==NULL) {
-			LM_ERR("invalid proto\n");
-			goto error;
-		}
-	}
-	*(p++) = '>';
-	memcpy(p, CRLF, CRLF_LEN);
-	p += CRLF_LEN;
+	memcpy(p, ">" CRLF, 1+CRLF_LEN);
+	p += 1+CRLF_LEN;
 
 	if (add_lump_rpl( msg, hdr_append, p-hdr_append, LUMP_RPL_HDR)==0 )
 	{
@@ -753,8 +739,8 @@ int handle_subscribe(struct sip_msg* msg, char* force_active_param, char* tag)
 }
 
 
-int extract_sdialog_info(subs_t* subs,struct sip_msg* msg, int mexp, int* init_req,
-		str local_address)
+int extract_sdialog_info(subs_t* subs,struct sip_msg* msg, int mexp,
+											int* init_req, str local_address)
 {
 	str rec_route= {0, 0};
 	int rt  = 0;

modules/presence/utils_func.h

@@ -36,7 +36,6 @@
 #include "../../str.h"
 #include "../../parser/msg_parser.h"
 
-#define LCONTACT_BUF_SIZE 1024
 #define BAD_EVENT_CODE 489
 
 static inline int uandd_to_uri(str user,  str domain, str *out)
@@ -70,52 +69,60 @@ static inline int uandd_to_uri(str user,  str domain, str *out)
 	return 0;
 }
 
-/* Build an contact URI but without the "transport" param - this is to be
- * added when a send is done, depending on the used interface.
+/* Build an contact URI with port and transport parameter
  */
 static inline int get_local_contact(struct socket_info *sock, str* contact)
 {
-	static char buf[LCONTACT_BUF_SIZE];
+	static char buf[MAX_URI_SIZE];
+	char *p;
 
-	contact->s = buf;
-	contact->len= 0;
-	memset(buf, 0, LCONTACT_BUF_SIZE);
+	p = buf;
 
 	/* write "sip:ip" */
-	memcpy(contact->s+contact->len, "sip:", 4);
-	contact->len+= 4;
+	memcpy( p, "sip:", 4);
+	p += 4;
 
 	/* if advertised address is set for this interface, use this one */
 	if (sock->adv_name_str.s) {
-		memcpy(contact->s+contact->len, sock->adv_name_str.s, sock->adv_name_str.len);
-		contact->len += sock->adv_name_str.len;
+		memcpy( p, sock->adv_name_str.s, sock->adv_name_str.len);
+		p += sock->adv_name_str.len;
 	}
 	else {
-		memcpy(contact->s+contact->len, sock->address_str.s, sock->address_str.len);
-		contact->len += sock->address_str.len;
-	}
-	if(contact->len> LCONTACT_BUF_SIZE - 21)
-	{
-		LM_ERR("buffer overflow\n");
-		return -1;
+		memcpy( p, sock->address_str.s, sock->address_str.len);
+		p += sock->address_str.len;
 	}
+	if ( (p-buf) < 6/*:nnnnn*/)
+		goto overflow;
 
 	/* write ":port" if port defined */
 	if (sock->adv_name_str.s) {
 		if(sock->adv_port_str.s) {
-			*(contact->s+(contact->len++)) = ':';
-			memcpy(contact->s+contact->len, sock->adv_port_str.s, sock->adv_port_str.len);
-			contact->len += sock->adv_port_str.len;
+			*(p++) = ':';
+			memcpy( p, sock->adv_port_str.s, sock->adv_port_str.len);
+			p += sock->adv_port_str.len;
 		}
-	}
-	else
+	} else
 	if (sock->port_no_str.len) {
-		*(contact->s+(contact->len++)) = ':';
-		memcpy(contact->s+contact->len, sock->port_no_str.s, sock->port_no_str.len);
-		contact->len += sock->port_no_str.len;
+		*(p++) = ':';
+		memcpy( p, sock->port_no_str.s, sock->port_no_str.len);
+		p += sock->port_no_str.len;
+	}
+
+	if (sock->proto!=PROTO_UDP) {
+		if ( (p-buf) < 15/*;transport=xxxx*/)
+			goto overflow;
+		memcpy( p, ";transport=", 11);
+		p += 11;
+		p = proto2str(sock->proto, p);
 	}
 
+	/* success */
+	contact->s = buf;
+	contact->len = (int)(p-buf);
 	return 0;
+overflow:
+	LM_ERR("local contact gets too long, exceeding %d\n",MAX_URI_SIZE);
+	return -1;
 }
 
 int a_to_i (char *s,int len);