nathelper(k): added the select for rewriting the contact

- exsting in the ser flavour version

modules_k/nathelper/README

@@ -78,6 +78,10 @@ Ovidiu Sas
 
               7.1. nh_enable_ping
 
+        8. Selects
+
+              8.1. @nathelper.rewrite_contact[n]
+
    2. Frequently Asked Questions
 
    List of Examples
@@ -102,6 +106,7 @@ Ovidiu Sas
    1.18. $rr_count usage
    1.19. $rr_top_count usage
    1.20. nh_enable_ping usage
+   1.21. @nathelper.rewrite_contact usage
 
 Chapter 1. Admin Guide
 
@@ -148,6 +153,10 @@ Chapter 1. Admin Guide
 
         7.1. nh_enable_ping
 
+   8. Selects
+
+        8.1. @nathelper.rewrite_contact[n]
+
 1. Overview
 
    This is a module to help with NAT traversal and reuse of tcp
@@ -396,7 +405,7 @@ modparam("nathelper", "keepalive_timeout", 120)
    5.7. add_contact_alias([ip_addr, port, proto])
    5.8. handle_ruri_alias()
 
-5.1.  fix_nated_contact()
+5.1. fix_nated_contact()
 
    Rewrites Contact HF to contain request's source address:port.
 
@@ -408,7 +417,7 @@ modparam("nathelper", "keepalive_timeout", 120)
 if (search("User-Agent: Cisco ATA.*") {fix_nated_contact();};
 ...
 
-5.2.  fix_nated_sdp(flags [, ip_address])
+5.2. fix_nated_sdp(flags [, ip_address])
 
    Alters the SDP information in orer to facilitate NAT traversal. What
    changes to be performed may be controled via the "flags" parameter.
@@ -436,7 +445,7 @@ if (search("User-Agent: Cisco ATA.*") {fix_nated_contact();};
 if (search("User-Agent: Cisco ATA.*") {fix_nated_sdp("3");};
 ...
 
-5.3.  add_rcv_param([flag]),
+5.3. add_rcv_param([flag]),
 
    Add received parameter to Contact header fields or Contact URI. The
    parameter will contain URI created from the source IP, port, and
@@ -460,7 +469,7 @@ add_rcv_param(); # add the parameter to the Contact header
 add_rcv_param("1"); # add the parameter to the Contact URI
 ...
 
-5.4.  fix_nated_register()
+5.4. fix_nated_register()
 
    The function creates a URI consisting of the source IP, port, and
    protocol and stores the URI in an Attribute-Value-Pair. The URI will be
@@ -478,7 +487,7 @@ add_rcv_param("1"); # add the parameter to the Contact URI
 fix_nated_register();
 ...
 
-5.5.  nat_uac_test(flags)
+5.5. nat_uac_test(flags)
 
    Tries to guess if client's request originated behind a nat. The
    parameter determines what heuristics is used.
@@ -501,14 +510,14 @@ fix_nated_register();
    This function can be used from REQUEST_ROUTE, ONREPLY_ROUTE,
    FAILURE_ROUTE, BRANCH_ROUTE.
 
-5.6.  is_rfc1918(ip_address)
+5.6. is_rfc1918(ip_address)
 
    Determines if the address in the parameter is an rfc1918 address. The
    parameter allows pseudo-variables usage.
 
    This function can be used from ANY_ROUTE.
 
-5.7.  add_contact_alias([ip_addr, port, proto])
+5.7. add_contact_alias([ip_addr, port, proto])
 
    Adds ;alias=ip~port~transport parameter to contact URI containing
    either received ip, port, and transport protocol or those given as
@@ -528,7 +537,7 @@ fix_nated_register();
     };
 ...
 
-5.8.  handle_ruri_alias()
+5.8. handle_ruri_alias()
 
    Checks if Request URI has alias param and if so, removes it and sets
    $du based on its value. Note that this means that routing of request is
@@ -607,6 +616,22 @@ fix_nated_register();
 $ kamctl fifo nh_enable_ping 1
 ...
 
+8. Selects
+
+   8.1. @nathelper.rewrite_contact[n]
+
+8.1. @nathelper.rewrite_contact[n]
+
+   Get n-th Contact value with IP:Port rewritten to source ip:port. N is
+   counted from 1. Only IP:port is rewritten, remaining part are left
+   unchanged. Full nameaddr is supported.
+
+   Example 1.21. @nathelper.rewrite_contact usage
+...
+$c = @nathelper.rewrite_contact[1];
+...
+$c2 = @nathelper.rewrite_contact[1].nameaddr.uri;
+
 Chapter 2. Frequently Asked Questions
 
    2.1. What happend with "rtpproxy_disable" parameter?

modules_k/nathelper/doc/nathelper_admin.xml

@@ -736,5 +736,27 @@ $ &ctltool; fifo nh_enable_ping 1
 
 	</section>
 
+	<section>
+		<title>Selects</title>
+
+		<section id="nathelper.rewrite_contact">
+		<title>@nathelper.rewrite_contact[n]</title>
+		<para>
+			Get n-th Contact value with IP:Port rewritten to source ip:port. N is counted from 1.
+		    Only IP:port is rewritten, remaining part are left unchanged. Full nameaddr is supported.
+		</para>
+		<example>
+			<title>@nathelper.rewrite_contact usage</title>
+			<programlisting>
+...
+$c = @nathelper.rewrite_contact[1];
+...
+$c2 = @nathelper.rewrite_contact[1].nameaddr.uri;
+			</programlisting>
+		</example>
+		</section>
+
+	</section>
+
 </chapter>
 

modules_k/nathelper/nathelper.c

@@ -220,6 +220,7 @@
 #include "../../socket_info.h"
 #include "../../mod_fix.h"
 #include "../../dset.h"
+#include "../../select.h"
 #include "../registrar/sip_msg.h"
 #include "../usrloc/usrloc.h"
 #include "nathelper.h"
@@ -439,6 +440,27 @@ struct module_exports exports = {
 };
 
 
+static int
+sel_nathelper(str* res, select_t* s, struct sip_msg* msg)
+{
+
+	/* dummy */
+	return 0;
+}
+
+static int sel_rewrite_contact(str* res, select_t* s, struct sip_msg* msg);
+
+SELECT_F(select_any_nameaddr)
+
+select_row_t sel_declaration[] = {
+	{ NULL, SEL_PARAM_STR, STR_STATIC_INIT("nathelper"), sel_nathelper, SEL_PARAM_EXPECTED},
+	{ sel_nathelper, SEL_PARAM_STR, STR_STATIC_INIT("rewrite_contact"), sel_rewrite_contact, CONSUME_NEXT_INT },
+
+	{ sel_rewrite_contact, SEL_PARAM_STR, STR_STATIC_INIT("nameaddr"), select_any_nameaddr, NESTED | CONSUME_NEXT_STR},
+
+	{ NULL, SEL_PARAM_INT, STR_NULL, NULL, 0}
+};
+
 static int
 fixup_fix_sdp(void** param, int param_no)
 {
@@ -689,6 +711,8 @@ mod_init(void)
 		nets_1918[i].netaddr = ntohl(addr.s_addr) & nets_1918[i].mask;
 	}
 
+	register_select_table(sel_declaration);
+
 	return 0;
 }
 
@@ -2292,3 +2316,59 @@ done:
 	/* let the core handle further the reply */
 	return 1;
 }
+
+static int
+sel_rewrite_contact(str* res, select_t* s, struct sip_msg* msg)
+{
+	static char buf[500];
+	contact_t* c;
+	int n, def_port_fl, len;
+	char *cp;
+	str hostport;
+	struct sip_uri uri;
+
+	res->len = 0;
+	n = s->params[2].v.i;
+	if (n <= 0) {
+		LOG(L_ERR, "ERROR: rewrite_contact[%d]: zero or negative index not supported\n", n);
+		return -1;
+	}
+	c = 0;
+	do {
+		if (contact_iterator(&c, msg, c) < 0 || !c)
+			return -1;
+		n--;
+	} while (n > 0);
+
+	if (parse_uri(c->uri.s, c->uri.len, &uri) < 0 || uri.host.len <= 0) {
+		LOG(L_ERR, "rewrite_contact[%d]: Error while parsing Contact URI\n", s->params[2].v.i);
+		return -1;
+	}
+	len = c->len - uri.host.len;
+	if (uri.port.len > 0)
+		len -= uri.port.len;
+	def_port_fl = (msg->rcv.proto == PROTO_TLS && msg->rcv.src_port == SIPS_PORT) || (msg->rcv.proto != PROTO_TLS && msg->rcv.src_port == SIP_PORT);
+	if (!def_port_fl)
+		len += 1/*:*/+5/*port*/;
+	if (len > sizeof(buf)) {
+		LOG(L_ERR, "ERROR: rewrite_contact[%d]: contact too long\n", s->params[2].v.i);
+		return -1;
+	}
+	hostport = uri.host;
+	if (uri.port.len > 0)
+		hostport.len = uri.port.s + uri.port.len - uri.host.s;
+
+	res->s = buf;
+	res->len = hostport.s - c->name.s;
+	memcpy(buf, c->name.s, res->len);
+	cp = ip_addr2a(&msg->rcv.src_ip);
+	if (def_port_fl) {
+		res->len+= snprintf(buf+res->len, sizeof(buf)-res->len, "%s", cp);
+	} else {
+		res->len+= snprintf(buf+res->len, sizeof(buf)-res->len, "%s:%d", cp, msg->rcv.src_port);
+	}
+	memcpy(buf+res->len, hostport.s+hostport.len, c->len-(hostport.s+hostport.len-c->name.s));
+	res->len+= c->len-(hostport.s+hostport.len-c->name.s);
+
+	return 0;
+}