--- /dev/null
+diff -urN linux-2.6.16.4/net/ipv4/netfilter/ip_conntrack_sip.c linux-2.6.16.4.new/net/ipv4/netfilter/ip_conntrack_sip.c
+--- linux-2.6.16.4/net/ipv4/netfilter/ip_conntrack_sip.c 1970-01-01 01:00:00.000000000 +0100
++++ linux-2.6.16.4.new/net/ipv4/netfilter/ip_conntrack_sip.c 2006-04-12 17:31:44.000000000 +0200
+@@ -0,0 +1,414 @@
++/* SIP extension for IP connection tracking.
++ *
++ * (C) 2005 by Christian Hentschel <chentschel@arnet.com.ar>
++ * based on RR's ip_conntrack_ftp.c and other modules.
++ *
++ * This program is free software; you can redistribute it and/or modify
++ * it under the terms of the GNU General Public License version 2 as
++ * published by the Free Software Foundation.
++ */
++
++#include <linux/config.h>
++#include <linux/module.h>
++#include <linux/netfilter.h>
++#include <linux/ip.h>
++#include <linux/ctype.h>
++#include <linux/in.h>
++#include <linux/udp.h>
++#include <net/checksum.h>
++#include <net/udp.h>
++
++#include <linux/netfilter_ipv4/ip_conntrack_helper.h>
++#include <linux/netfilter_ipv4/ip_conntrack_sip.h>
++
++MODULE_LICENSE("GPL");
++MODULE_AUTHOR("Christian Hentschel <chentschel@arnet.com.ar>");
++MODULE_DESCRIPTION("SIP connection tracking helper");
++
++static DEFINE_SPINLOCK(sipbf_lock);
++
++
++#define MAX_PORTS 8
++static int ports[MAX_PORTS];
++static int ports_c;
++module_param_array(ports, int, &ports_c, 0400);
++MODULE_PARM_DESC(ports, " port numbers of sip servers");
++
++static unsigned int sip_timeout = SIP_TIMEOUT;
++
++module_param(sip_timeout, int, 0600);
++MODULE_PARM_DESC(sip_timeout, "timeout for the master sip session");
++
++unsigned int (*ip_nat_sip_hook)(struct sk_buff **pskb,
++ enum ip_conntrack_info ctinfo,
++ struct ip_conntrack *ct,
++ const char **dptr);
++EXPORT_SYMBOL_GPL(ip_nat_sip_hook);
++
++unsigned int (*ip_nat_sdp_hook)(struct sk_buff **pskb,
++ enum ip_conntrack_info ctinfo,
++ struct ip_conntrack_expect *exp,
++ const char *dptr);
++EXPORT_SYMBOL_GPL(ip_nat_sdp_hook);
++
++int ct_sip_get_info(const char *dptr, size_t dlen,
++ unsigned int *matchoff,
++ unsigned int *matchlen,
++ struct sip_header_nfo *hnfo);
++EXPORT_SYMBOL(ct_sip_get_info);
++
++#if 0
++#define DEBUGP printk
++#else
++#define DEBUGP(format, args...)
++#endif
++
++static int digits_len(const char *dptr, const char *limit, int *shift);
++static int epaddr_len(const char *dptr, const char *limit, int *shift);
++static int skp_digits_len(const char *dptr, const char *limit, int *shift);
++static int skp_epaddr_len(const char *dptr, const char *limit, int *shift);
++
++struct sip_header_nfo ct_sip_hdrs[] = {
++ { /* Via header */
++ "Via:", sizeof("Via:") - 1,
++ "\r\nv:", sizeof("\r\nv:") - 1, /* rfc3261 "\r\n" */
++ "UDP ", sizeof("UDP ") - 1,
++ epaddr_len
++ },
++ { /* Contact header */
++ "Contact:", sizeof("Contact:") - 1,
++ "\r\nm:", sizeof("\r\nm:") - 1,
++ "sip:", sizeof("sip:") - 1,
++ skp_epaddr_len
++ },
++ { /* Content length header */
++ "Content-Length:", sizeof("Content-Length:") - 1,
++ "\r\nl:", sizeof("\r\nl:") - 1,
++ ":", sizeof(":") - 1,
++ skp_digits_len
++ },
++ { /* SDP media info */
++ "\nm=", sizeof("\nm=") - 1,
++ "\rm=", sizeof("\rm=") - 1,
++ "audio ", sizeof("audio ") - 1,
++ digits_len
++ },
++ { /* SDP owner address*/
++ "\no=", sizeof("\no=") - 1,
++ "\ro=", sizeof("\ro=") - 1,
++ "IN IP4 ", sizeof("IN IP4 ") - 1,
++ epaddr_len
++ },
++ { /* SDP connection info */
++ "\nc=", sizeof("\nc=") - 1,
++ "\rc=", sizeof("\rc=") - 1,
++ "IN IP4 ", sizeof("IN IP4 ") - 1,
++ epaddr_len
++ },
++ { /* Requests headers */
++ "sip:", sizeof("sip:") - 1,
++ "sip:", sizeof("sip:") - 1, /* yes, i know.. ;) */
++ "@", sizeof("@") - 1,
++ epaddr_len
++ },
++ { /* SDP version header */
++ "\nv=", sizeof("\nv=") - 1,
++ "\rv=", sizeof("\rv=") - 1,
++ "=", sizeof("=") - 1,
++ digits_len
++ }
++};
++EXPORT_SYMBOL(ct_sip_hdrs);
++
++
++static int digits_len(const char *dptr, const char *limit, int *shift)
++{
++ int len = 0;
++ while (dptr <= limit && isdigit(*dptr)) {
++ dptr++;
++ len++;
++ }
++ return len;
++}
++
++/* get digits lenght, skiping blank spaces. */
++static int skp_digits_len(const char *dptr, const char *limit, int *shift)
++{
++ for (; dptr <= limit && *dptr == ' '; dptr++)
++ (*shift)++;
++
++ return digits_len(dptr, limit, shift);
++}
++
++/* Simple ipaddr parser.. */
++static int parse_ipaddr(const char *cp, const char **endp,
++ uint32_t *ipaddr, const char *limit)
++{
++ unsigned long int val;
++ int i, digit = 0;
++
++ for (i = 0, *ipaddr = 0; cp <= limit && i < 4; i++) {
++ digit = 0;
++ if (!isdigit(*cp))
++ break;
++
++ val = simple_strtoul(cp, (char **)&cp, 10);
++ if (val > 0xFF)
++ return -1;
++
++ ((uint8_t *)ipaddr)[i] = val;
++ digit = 1;
++
++ if (*cp != '.')
++ break;
++ cp++;
++ }
++ if (!digit)
++ return -1;
++
++ if (endp)
++ *endp = cp;
++
++ return 0;
++}
++
++/* skip ip address. returns it lenght. */
++static int epaddr_len(const char *dptr, const char *limit, int *shift)
++{
++ const char *aux = dptr;
++ uint32_t ip;
++
++ if (parse_ipaddr(dptr, &dptr, &ip, limit) < 0) {
++ DEBUGP("ip: %s parse failed.!\n", dptr);
++ return 0;
++ }
++
++ /* Port number */
++ if (*dptr == ':') {
++ dptr++;
++ dptr += digits_len(dptr, limit, shift);
++ }
++ return dptr - aux;
++}
++
++/* get address lenght, skiping user info. */
++static int skp_epaddr_len(const char *dptr, const char *limit, int *shift)
++{
++ for (; dptr <= limit && *dptr != '@'; dptr++)
++ (*shift)++;
++
++ if (*dptr == '@') {
++ dptr++;
++ (*shift)++;
++ return epaddr_len(dptr, limit, shift);
++ }
++ return 0;
++}
++
++/* Returns 0 if not found, -1 error parsing. */
++int ct_sip_get_info(const char *dptr, size_t dlen,
++ unsigned int *matchoff,
++ unsigned int *matchlen,
++ struct sip_header_nfo *hnfo)
++{
++ const char *limit, *aux, *k = dptr;
++ int shift = 0;
++
++ limit = dptr + (dlen - hnfo->lnlen);
++
++ while (dptr <= limit) {
++ if ((strncmp(dptr, hnfo->lname, hnfo->lnlen) != 0) &&
++ (strncmp(dptr, hnfo->sname, hnfo->snlen) != 0))
++ {
++ dptr++;
++ continue;
++ }
++ aux = ct_sip_search(hnfo->ln_str, dptr, hnfo->ln_strlen,
++ ct_sip_lnlen(dptr, limit));
++ if (!aux) {
++ DEBUGP("'%s' not found in '%s'.\n", hnfo->ln_str, hnfo->lname);
++ return -1;
++ }
++ aux += hnfo->ln_strlen;
++
++ *matchlen = hnfo->match_len(aux, limit, &shift);
++ if (!*matchlen)
++ return -1;
++
++ *matchoff = (aux - k) + shift;
++
++ DEBUGP("%s match succeeded! - len: %u\n", hnfo->lname, *matchlen);
++ return 1;
++ }
++ DEBUGP("%s header not found.\n", hnfo->lname);
++ return 0;
++}
++
++static int set_expected_rtp(struct sk_buff **pskb,
++ struct ip_conntrack *ct,
++ enum ip_conntrack_info ctinfo,
++ uint32_t ipaddr, uint16_t port,
++ const char *dptr)
++{
++ struct ip_conntrack_expect *exp;
++ int ret;
++
++ exp = ip_conntrack_expect_alloc(ct);
++ if (exp == NULL)
++ return NF_DROP;
++
++ exp->tuple = ((struct ip_conntrack_tuple)
++ { { ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.ip, { 0 } },
++ { ipaddr, { .udp = { htons(port) } }, IPPROTO_UDP }});
++
++ exp->mask = ((struct ip_conntrack_tuple)
++ { { 0xFFFFFFFF, { 0 } },
++ { 0xFFFFFFFF, { .udp = { 0xFFFF } }, 0xFF }});
++
++ exp->expectfn = NULL;
++
++ if (ip_nat_sdp_hook)
++ ret = ip_nat_sdp_hook(pskb, ctinfo, exp, dptr);
++ else {
++ if (ip_conntrack_expect_related(exp) != 0)
++ ret = NF_DROP;
++ else
++ ret = NF_ACCEPT;
++ }
++ ip_conntrack_expect_put(exp);
++
++ return ret;
++}
++
++static int sip_help(struct sk_buff **pskb,
++ struct ip_conntrack *ct,
++ enum ip_conntrack_info ctinfo)
++{
++ unsigned int dataoff, datalen;
++ const char *dptr;
++ int ret = NF_ACCEPT;
++ int matchoff, matchlen;
++ uint32_t ipaddr;
++ uint16_t port;
++
++ /* No Data ? */
++ dataoff = (*pskb)->nh.iph->ihl*4 + sizeof(struct udphdr);
++ if (dataoff >= (*pskb)->len) {
++ DEBUGP("skb->len = %u\n", (*pskb)->len);
++ return NF_ACCEPT;
++ }
++
++ ip_ct_refresh(ct, *pskb, sip_timeout * HZ);
++
++ spin_lock_bh(&sipbf_lock);
++
++ if ((dataoff + (*pskb)->len - dataoff) <= skb_headlen(*pskb))
++ dptr = (*pskb)->data + dataoff;
++ else {
++ DEBUGP("Copy of skbuff not supported yet.\n");
++ goto out;
++ }
++
++ if (ip_nat_sip_hook) {
++ if (!ip_nat_sip_hook(pskb, ctinfo, ct, &dptr)) {
++ ret = NF_DROP;
++ goto out;
++ }
++ }
++
++ if ((ctinfo) >= IP_CT_IS_REPLY)
++ goto out;
++
++ /* After this point NAT, could have mangled skb, so
++ we need to recalculate payload lenght. */
++ datalen = (*pskb)->len - dataoff;
++
++ if (datalen < (sizeof("SIP/2.0 200") - 1))
++ goto out;
++
++ /* RTP info only in some SDP pkts */
++ if (memcmp(dptr, "INVITE", sizeof("INVITE") - 1) != 0 &&
++ memcmp(dptr, "SIP/2.0 200", sizeof("SIP/2.0 200") - 1) != 0) {
++ goto out;
++ }
++ /* Get ip and port address from SDP packet. */
++ if (ct_sip_get_info(dptr, datalen, &matchoff, &matchlen,
++ &ct_sip_hdrs[POS_CONECTION]) > 0) {
++
++ /* We'll drop only if there are parse problems. */
++ if (parse_ipaddr(dptr + matchoff, NULL, &ipaddr,
++ dptr + datalen) < 0) {
++ ret = NF_DROP;
++ goto out;
++ }
++ if (ct_sip_get_info(dptr, datalen, &matchoff, &matchlen,
++ &ct_sip_hdrs[POS_MEDIA]) > 0) {
++
++ port = simple_strtoul(dptr + matchoff, NULL, 10);
++ if (port < 1024) {
++ ret = NF_DROP;
++ goto out;
++ }
++ ret = set_expected_rtp(pskb, ct, ctinfo,
++ ipaddr, port, dptr);
++ }
++ }
++out: spin_unlock_bh(&sipbf_lock);
++ return ret;
++}
++
++static struct ip_conntrack_helper sip[MAX_PORTS];
++static char sip_names[MAX_PORTS][10];
++
++static void fini(void)
++{
++ int i = 0;
++ for (; i < ports_c; i++) {
++ DEBUGP("unregistering helper for port %d\n", ports[i]);
++ ip_conntrack_helper_unregister(&sip[i]);
++ }
++}
++
++static int __init init(void)
++{
++ int i, ret;
++ char *tmpname;
++
++ if (ports_c == 0)
++ ports[ports_c++] = SIP_PORT;
++
++ for (i = 0; i < ports_c; i++) {
++ /* Create helper structure */
++ memset(&sip[i], 0, sizeof(struct ip_conntrack_helper));
++
++ sip[i].tuple.dst.protonum = IPPROTO_UDP;
++ sip[i].tuple.src.u.udp.port = htons(ports[i]);
++ sip[i].mask.src.u.udp.port = 0xFFFF;
++ sip[i].mask.dst.protonum = 0xFF;
++ sip[i].max_expected = 1;
++ sip[i].timeout = 3 * 60; /* 3 minutes */
++ sip[i].me = THIS_MODULE;
++ sip[i].help = sip_help;
++
++ tmpname = &sip_names[i][0];
++ if (ports[i] == SIP_PORT)
++ sprintf(tmpname, "sip");
++ else
++ sprintf(tmpname, "sip-%d", i);
++ sip[i].name = tmpname;
++
++ DEBUGP("port #%d: %d\n", i, ports[i]);
++
++ ret=ip_conntrack_helper_register(&sip[i]);
++ if (ret) {
++ printk("ERROR registering helper for port %d\n",
++ ports[i]);
++ fini();
++ return(ret);
++ }
++ }
++ return(0);
++}
++
++module_init(init);
++module_exit(fini);
+diff -urN linux-2.6.16.4/net/ipv4/netfilter/ip_nat_sip.c linux-2.6.16.4.new/net/ipv4/netfilter/ip_nat_sip.c
+--- linux-2.6.16.4/net/ipv4/netfilter/ip_nat_sip.c 1970-01-01 01:00:00.000000000 +0100
++++ linux-2.6.16.4.new/net/ipv4/netfilter/ip_nat_sip.c 2006-04-12 17:31:53.000000000 +0200
+@@ -0,0 +1,249 @@
++/* SIP extension for UDP NAT alteration.
++ *
++ * (C) 2005 by Christian Hentschel <chentschel@arnet.com.ar>
++ * based on RR's ip_nat_ftp.c and other modules.
++ *
++ * This program is free software; you can redistribute it and/or modify
++ * it under the terms of the GNU General Public License version 2 as
++ * published by the Free Software Foundation.
++ */
++
++#include <linux/module.h>
++#include <linux/netfilter_ipv4.h>
++#include <linux/ip.h>
++#include <linux/udp.h>
++#include <net/udp.h>
++
++#include <linux/netfilter_ipv4/ip_nat.h>
++#include <linux/netfilter_ipv4/ip_nat_helper.h>
++#include <linux/netfilter_ipv4/ip_conntrack_helper.h>
++#include <linux/netfilter_ipv4/ip_conntrack_sip.h>
++
++MODULE_LICENSE("GPL");
++MODULE_AUTHOR("Christian Hentschel <chentschel@arnet.com.ar>");
++MODULE_DESCRIPTION("SIP NAT helper");
++
++#if 0
++#define DEBUGP printk
++#else
++#define DEBUGP(format, args...)
++#endif
++
++extern struct sip_header_nfo ct_sip_hdrs[];
++
++static unsigned int mangle_sip_packet(struct sk_buff **pskb,
++ enum ip_conntrack_info ctinfo,
++ struct ip_conntrack *ct,
++ const char **dptr, size_t dlen,
++ char *buffer, int bufflen,
++ struct sip_header_nfo *hnfo)
++{
++ unsigned int matchlen, matchoff;
++
++ if (ct_sip_get_info(*dptr, dlen, &matchoff, &matchlen, hnfo) <= 0)
++ return 0;
++
++ if (!ip_nat_mangle_udp_packet(pskb, ct, ctinfo,
++ matchoff, matchlen, buffer, bufflen)) {
++ return 0;
++ }
++ /* We need to reload this. Thanks Patrick. */
++ *dptr = (*pskb)->data + (*pskb)->nh.iph->ihl*4 + sizeof(struct udphdr);
++ return 1;
++}
++
++static unsigned int ip_nat_sip(struct sk_buff **pskb,
++ enum ip_conntrack_info ctinfo,
++ struct ip_conntrack *ct,
++ const char **dptr)
++{
++ char buffer[sizeof("nnn.nnn.nnn.nnn:nnnnn")];
++ unsigned int bufflen, dataoff;
++ uint32_t ip;
++ uint16_t port;
++
++ dataoff = (*pskb)->nh.iph->ihl*4 + sizeof(struct udphdr);
++
++ if ((ctinfo) >= IP_CT_IS_REPLY) {
++ ip = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip;
++ port = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.udp.port;
++ } else {
++ ip = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip;
++ port = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u.udp.port;
++ }
++ bufflen = sprintf(buffer, "%u.%u.%u.%u:%u", NIPQUAD(ip), ntohs(port));
++
++ /* short packet ? */
++ if (((*pskb)->len - dataoff) < (sizeof("SIP/2.0") - 1))
++ return 0;
++
++ /* Basic rules: requests and responses. */
++ if (memcmp(*dptr, "SIP/2.0", sizeof("SIP/2.0") - 1) == 0) {
++
++ if ((ctinfo) < IP_CT_IS_REPLY) {
++ mangle_sip_packet(pskb, ctinfo, ct, dptr,
++ (*pskb)->len - dataoff, buffer, bufflen,
++ &ct_sip_hdrs[POS_CONTACT]);
++ return 1;
++ }
++
++ if (!mangle_sip_packet(pskb, ctinfo, ct, dptr, (*pskb)->len - dataoff,
++ buffer, bufflen, &ct_sip_hdrs[POS_VIA])) {
++ return 0;
++ }
++
++ /* This search should ignore case, but later.. */
++ const char *aux = ct_sip_search("CSeq:", *dptr, sizeof("CSeq:") - 1,
++ (*pskb)->len - dataoff);
++ if (!aux)
++ return 0;
++
++ if (!ct_sip_search("REGISTER", aux, sizeof("REGISTER"),
++ ct_sip_lnlen(aux, *dptr + (*pskb)->len - dataoff))) {
++ return 1;
++ }
++ return mangle_sip_packet(pskb, ctinfo, ct, dptr, (*pskb)->len - dataoff,
++ buffer, bufflen, &ct_sip_hdrs[POS_CONTACT]);
++ }
++ if ((ctinfo) < IP_CT_IS_REPLY) {
++ if (!mangle_sip_packet(pskb, ctinfo, ct, dptr, (*pskb)->len - dataoff,
++ buffer, bufflen, &ct_sip_hdrs[POS_VIA])) {
++ return 0;
++ }
++
++ /* Mangle Contact if exists only. - watch udp_nat_mangle()! */
++ mangle_sip_packet(pskb, ctinfo, ct, dptr, (*pskb)->len - dataoff,
++ buffer, bufflen, &ct_sip_hdrs[POS_CONTACT]);
++ return 1;
++ }
++ /* This mangle requests headers. */
++ return mangle_sip_packet(pskb, ctinfo, ct, dptr,
++ ct_sip_lnlen(*dptr, *dptr + (*pskb)->len - dataoff),
++ buffer, bufflen, &ct_sip_hdrs[POS_REQ_HEADER]);
++}
++
++static int mangle_content_len(struct sk_buff **pskb,
++ enum ip_conntrack_info ctinfo,
++ struct ip_conntrack *ct,
++ const char *dptr)
++{
++ unsigned int dataoff, matchoff, matchlen;
++ char buffer[sizeof("65536")];
++ int bufflen;
++
++ dataoff = (*pskb)->nh.iph->ihl*4 + sizeof(struct udphdr);
++
++ /* Get actual SDP lenght */
++ if (ct_sip_get_info(dptr, (*pskb)->len - dataoff, &matchoff,
++ &matchlen, &ct_sip_hdrs[POS_SDP_HEADER]) > 0) {
++
++ /* since ct_sip_get_info() give us a pointer passing 'v='
++ we need to add 2 bytes in this count. */
++ int c_len = (*pskb)->len - dataoff - matchoff + 2;
++
++ /* Now, update SDP lenght */
++ if (ct_sip_get_info(dptr, (*pskb)->len - dataoff, &matchoff,
++ &matchlen, &ct_sip_hdrs[POS_CONTENT]) > 0) {
++
++ bufflen = sprintf(buffer, "%u", c_len);
++
++ return ip_nat_mangle_udp_packet(pskb, ct, ctinfo, matchoff,
++ matchlen, buffer, bufflen);
++ }
++ }
++ return 0;
++}
++
++static unsigned int mangle_sdp(struct sk_buff **pskb,
++ enum ip_conntrack_info ctinfo,
++ struct ip_conntrack *ct,
++ uint32_t newip, uint16_t port,
++ const char *dptr)
++{
++ char buffer[sizeof("nnn.nnn.nnn.nnn")];
++ unsigned int dataoff, bufflen;
++
++ dataoff = (*pskb)->nh.iph->ihl*4 + sizeof(struct udphdr);
++
++ /* Mangle owner and contact info. */
++ bufflen = sprintf(buffer, "%u.%u.%u.%u", NIPQUAD(newip));
++ if (!mangle_sip_packet(pskb, ctinfo, ct, &dptr, (*pskb)->len - dataoff,
++ buffer, bufflen, &ct_sip_hdrs[POS_OWNER])) {
++ return 0;
++ }
++
++ if (!mangle_sip_packet(pskb, ctinfo, ct, &dptr, (*pskb)->len - dataoff,
++ buffer, bufflen, &ct_sip_hdrs[POS_CONECTION])) {
++ return 0;
++ }
++
++ /* Mangle media port. */
++ bufflen = sprintf(buffer, "%u", port);
++ if (!mangle_sip_packet(pskb, ctinfo, ct, &dptr, (*pskb)->len - dataoff,
++ buffer, bufflen, &ct_sip_hdrs[POS_MEDIA])) {
++ return 0;
++ }
++
++ return mangle_content_len(pskb, ctinfo, ct, dptr);
++}
++
++/* So, this packet has hit the connection tracking matching code.
++ Mangle it, and change the expectation to match the new version. */
++static unsigned int ip_nat_sdp(struct sk_buff **pskb,
++ enum ip_conntrack_info ctinfo,
++ struct ip_conntrack_expect *exp,
++ const char *dptr)
++{
++ struct ip_conntrack *ct = exp->master;
++ uint32_t newip;
++ uint16_t port;
++
++ DEBUGP("ip_nat_sdp():\n");
++
++ /* Connection will come from reply */
++ newip = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip;
++
++ exp->tuple.dst.ip = newip;
++ exp->saved_proto.udp.port = exp->tuple.dst.u.udp.port;
++ exp->dir = IP_CT_DIR_REPLY;
++
++ /* When you see the packet, we need to NAT it the same as the
++ this one. */
++ exp->expectfn = ip_nat_follow_master;
++
++ /* Try to get same port: if not, try to change it. */
++ for (port = ntohs(exp->saved_proto.udp.port); port != 0; port++) {
++ exp->tuple.dst.u.udp.port = htons(port);
++ if (ip_conntrack_expect_related(exp) == 0)
++ break;
++ }
++
++ if (port == 0)
++ return NF_DROP;
++
++ if (!mangle_sdp(pskb, ctinfo, ct, newip, port, dptr)) {
++ ip_conntrack_unexpect_related(exp);
++ return NF_DROP;
++ }
++ return NF_ACCEPT;
++}
++
++static void __exit fini(void)
++{
++ ip_nat_sip_hook = NULL;
++ ip_nat_sdp_hook = NULL;
++ /* Make sure noone calls it, meanwhile. */
++ synchronize_net();
++}
++
++static int __init init(void)
++{
++ BUG_ON(ip_nat_sip_hook);
++ BUG_ON(ip_nat_sdp_hook);
++ ip_nat_sip_hook = ip_nat_sip;
++ ip_nat_sdp_hook = ip_nat_sdp;
++ return 0;
++}
++
++module_init(init);
++module_exit(fini);
+diff -urN linux-2.6.16.4/net/ipv4/netfilter/Kconfig linux-2.6.16.4.new/net/ipv4/netfilter/Kconfig
+--- linux-2.6.16.4/net/ipv4/netfilter/Kconfig 2006-04-12 17:29:19.000000000 +0200
++++ linux-2.6.16.4.new/net/ipv4/netfilter/Kconfig 2006-04-12 17:32:53.000000000 +0200
+@@ -168,6 +168,19 @@
+ If you want to compile it as a module, say M here and read
+ Documentation/modules.txt. If unsure, say `N'.
+
++config IP_NF_SIP
++ tristate 'SIP support'
++ depends on IP_NF_CONNTRACK
++ help
++ SIP is an application-layer control protocol that can establish,
++ modify, and terminate multimedia sessions (conferences) such as
++ Internet telephony calls. With the ip_conntrack_sip and
++ the ip_nat_sip modules you can support the protocol on a connection
++ tracking/NATing firewall.
++
++ If you want to compile it as a module, say 'M' here and read
++ Documentation/modules.txt. If unsure, say 'N'.
++
+ config IP_NF_QUEUE
+ tristate "IP Userspace queueing via NETLINK (OBSOLETE)"
+ help
+@@ -545,6 +558,12 @@
+ default IP_NF_NAT if IP_NF_PPTP=y
+ default m if IP_NF_PPTP=m
+
++config IP_NF_NAT_SIP
++ tristate
++ depends on IP_NF_CONNTRACK!=n && IP_NF_NAT!=n
++ default IP_NF_NAT if IP_NF_SIP=y
++ default m if IP_NF_SIP=m
++
+ # mangle + specific targets
+ config IP_NF_MANGLE
+ tristate "Packet mangling"
+diff -urN linux-2.6.16.4/net/ipv4/netfilter/Makefile linux-2.6.16.4.new/net/ipv4/netfilter/Makefile
+--- linux-2.6.16.4/net/ipv4/netfilter/Makefile 2006-04-12 17:29:19.000000000 +0200
++++ linux-2.6.16.4.new/net/ipv4/netfilter/Makefile 2006-04-12 17:33:39.000000000 +0200
+@@ -28,6 +28,7 @@
+ obj-$(CONFIG_IP_NF_FTP) += ip_conntrack_ftp.o
+ obj-$(CONFIG_IP_NF_IRC) += ip_conntrack_irc.o
+ obj-$(CONFIG_IP_NF_NETBIOS_NS) += ip_conntrack_netbios_ns.o
++obj-$(CONFIG_IP_NF_SIP) += ip_conntrack_sip.o
+
+ # NAT helpers
+ obj-$(CONFIG_IP_NF_NAT_PPTP) += ip_nat_pptp.o
+@@ -35,6 +36,7 @@
+ obj-$(CONFIG_IP_NF_NAT_TFTP) += ip_nat_tftp.o
+ obj-$(CONFIG_IP_NF_NAT_FTP) += ip_nat_ftp.o
+ obj-$(CONFIG_IP_NF_NAT_IRC) += ip_nat_irc.o
++obj-$(CONFIG_IP_NF_NAT_SIP) += ip_nat_sip.o
+
+ # generic IP tables
+ obj-$(CONFIG_IP_NF_IPTABLES) += ip_tables.o
+diff -urN linux-2.6.16.4/include/linux/netfilter_ipv4/ip_conntrack.h linux-2.6.16.4.new/include/linux/netfilter_ipv4/ip_conntrack.h
+--- linux-2.6.16.4/include/linux/netfilter_ipv4/ip_conntrack.h 2006-04-12 17:29:19.000000000 +0200
++++ linux-2.6.16.4.new/include/linux/netfilter_ipv4/ip_conntrack.h 2006-04-12 17:30:38.000000000 +0200
+@@ -33,6 +33,7 @@
+ #include <linux/netfilter_ipv4/ip_conntrack_amanda.h>
+ #include <linux/netfilter_ipv4/ip_conntrack_ftp.h>
+ #include <linux/netfilter_ipv4/ip_conntrack_irc.h>
++#include <linux/netfilter_ipv4/ip_conntrack_sip.h>
+
+ /* per conntrack: application helper private data */
+ union ip_conntrack_help {
+@@ -40,6 +41,7 @@
+ struct ip_ct_pptp_master ct_pptp_info;
+ struct ip_ct_ftp_master ct_ftp_info;
+ struct ip_ct_irc_master ct_irc_info;
++ struct ip_ct_sip_master ct_sip_info;
+ };
+
+ #ifdef CONFIG_IP_NF_NAT_NEEDED
+diff -urN linux-2.6.16.4/include/linux/netfilter_ipv4/ip_conntrack_sip.h linux-2.6.16.4.new/include/linux/netfilter_ipv4/ip_conntrack_sip.h
+--- linux-2.6.16.4/include/linux/netfilter_ipv4/ip_conntrack_sip.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-2.6.16.4.new/include/linux/netfilter_ipv4/ip_conntrack_sip.h 2006-04-12 17:31:12.000000000 +0200
+@@ -0,0 +1,81 @@
++#ifndef __IP_CONNTRACK_SIP_H__
++#define __IP_CONNTRACK_SIP_H__
++/* SIP tracking. */
++
++#ifdef __KERNEL__
++
++#define SIP_PORT 5060
++#define SIP_TIMEOUT 3600
++
++#define POS_VIA 0
++#define POS_CONTACT 1
++#define POS_CONTENT 2
++#define POS_MEDIA 3
++#define POS_OWNER 4
++#define POS_CONECTION 5
++#define POS_REQ_HEADER 6
++#define POS_SDP_HEADER 7
++
++struct ip_ct_sip_master {
++};
++
++struct sip_header_nfo {
++ const char *lname;
++ size_t lnlen;
++ const char *sname;
++ size_t snlen;
++ const char *ln_str;
++ size_t ln_strlen;
++ int (*match_len)(const char *, const char *, int *);
++
++};
++
++extern unsigned int (*ip_nat_sip_hook)(struct sk_buff **pskb,
++ enum ip_conntrack_info ctinfo,
++ struct ip_conntrack *ct,
++ const char **dptr);
++
++/* For NAT to hook in when on expect. */
++extern unsigned int (*ip_nat_sdp_hook)(struct sk_buff **pskb,
++ enum ip_conntrack_info ctinfo,
++ struct ip_conntrack_expect *exp,
++ const char *dptr);
++
++extern int ct_sip_get_info(const char *dptr, size_t dlen,
++ unsigned int *matchoff,
++ unsigned int *matchlen,
++ struct sip_header_nfo *hnfo);
++
++/* get line lenght until first CR or LF seen. */
++static __inline__ int ct_sip_lnlen(const char *line, const char *limit)
++{
++ const char *k = line;
++
++ while ((line <= limit) && (*line == '\r' || *line == '\n'))
++ line++;
++
++ while (line <= limit) {
++ if (*line == '\r' || *line == '\n')
++ break;
++ line++;
++ }
++ return line - k;
++}
++
++/* Linear string search, case sensitive. */
++static __inline__
++const char *ct_sip_search(const char *needle, const char *haystack,
++ size_t needle_len, size_t haystack_len)
++{
++ const char *limit = haystack + (haystack_len - needle_len);
++
++ while (haystack <= limit) {
++ if (memcmp(haystack, needle, needle_len) == 0)
++ return haystack;
++ haystack++;
++ }
++ return NULL;
++}
++#endif /* __KERNEL__ */
++
++#endif /* __IP_CONNTRACK_SIP_H__ */
projects / openwrt.git / commitdiff