diff --git a/openwrt/target/linux/linux-2.4/patches/generic/613-netfilter_nat_sip.patch b/openwrt/target/linux/linux-2.4/patches/generic/613-netfilter_nat_sip.patch new file mode 100644 index 000000000..4f55935b8 --- /dev/null +++ b/openwrt/target/linux/linux-2.4/patches/generic/613-netfilter_nat_sip.patch @@ -0,0 +1,1254 @@ +diff -urN linux-2.4.32/net/ipv4/netfilter/Config.in linux-2.4.32/net/ipv4/netfilter/Config.in +--- linux-2.4.32/net/ipv4/netfilter/Config.in 2005-12-11 21:34:32.000000000 +0100 ++++ linux-2.4.32/net/ipv4/netfilter/Config.in 2005-12-11 21:38:12.000000000 +0100 +@@ -15,6 +15,7 @@ + dep_tristate ' Connection byte counter support' CONFIG_IP_NF_MATCH_CONNBYTES $CONFIG_IP_NF_CT_ACCT $CONFIG_IP_NF_CONNTRACK $CONFIG_IP_NF_IPTABLES + dep_tristate ' GRE protocol support' CONFIG_IP_NF_CT_PROTO_GRE $CONFIG_IP_NF_CONNTRACK + dep_tristate ' PPTP protocol support' CONFIG_IP_NF_PPTP $CONFIG_IP_NF_CT_PROTO_GRE ++ dep_tristate ' SIP protocol support' CONFIG_IP_NF_SIP $CONFIG_IP_NF_CONNTRACK + fi + + if [ "$CONFIG_EXPERIMENTAL" = "y" ]; then +@@ -104,6 +105,13 @@ + define_tristate CONFIG_IP_NF_NAT_PROTO_GRE $CONFIG_IP_NF_NAT + fi + fi ++ if [ "$CONFIG_IP_NF_SIP" = "m" ]; then ++ define_tristate CONFIG_IP_NF_NAT_SIP m ++ else ++ if [ "$CONFIG_IP_NF_SIP" = "y" ]; then ++ define_tristate CONFIG_IP_NF_NAT_SIP $CONFIG_IP_NF_NAT ++ fi ++ fi + if [ "$CONFIG_IP_NF_AMANDA" = "m" ]; then + define_tristate CONFIG_IP_NF_NAT_AMANDA m + else +diff -urN linux-2.4.32/net/ipv4/netfilter/Makefile linux-2.4.32/net/ipv4/netfilter/Makefile +--- linux-2.4.32/net/ipv4/netfilter/Makefile 2005-12-11 21:34:32.000000000 +0100 ++++ linux-2.4.32/net/ipv4/netfilter/Makefile 2005-12-11 21:39:08.000000000 +0100 +@@ -53,6 +53,10 @@ + ifdef CONFIG_IP_NF_NAT_PPTP + export-objs += ip_conntrack_pptp.o + endif ++obj-$(CONFIG_IP_NF_SIP) += ip_conntrack_sip.o ++ifdef CONFIG_IP_NF_NAT_SIP ++ export-objs += ip_conntrack_sip.o ++endif + + + # NAT helpers +@@ -62,6 +66,7 @@ + obj-$(CONFIG_IP_NF_NAT_IRC) += ip_nat_irc.o + obj-$(CONFIG_IP_NF_NAT_PROTO_GRE) += ip_nat_proto_gre.o + obj-$(CONFIG_IP_NF_NAT_PPTP) += ip_nat_pptp.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-2.4.32/net/ipv4/netfilter/ip_conntrack_sip.c linux-2.4.32/net/ipv4/netfilter/ip_conntrack_sip.c +--- linux-2.4.32/net/ipv4/netfilter/ip_conntrack_sip.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-2.4.32/net/ipv4/netfilter/ip_conntrack_sip.c 2005-12-11 21:35:51.000000000 +0100 +@@ -0,0 +1,312 @@ ++/* ++ * SIP extension for IP connection tracking. ++ * ++ * Copyright (C) 2004, CyberTAN Corporation ++ * All Rights Reserved. ++ * ++ * THIS SOFTWARE IS OFFERED "AS IS", AND CYBERTAN GRANTS NO WARRANTIES OF ANY ++ * KIND, EXPRESS OR IMPLIED, BY STATUTE, COMMUNICATION OR OTHERWISE. CYBERTAN ++ * SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS ++ * FOR A SPECIFIC PURPOSE OR NONINFRINGEMENT CONCERNING THIS SOFTWARE. ++ * ++ */ ++ ++#include ++#include ++#include ++#include ++#include ++#include ++ ++#include ++#include ++#include ++#include ++ ++DECLARE_LOCK(ip_sip_lock); ++ ++struct module *ip_conntrack_sip = THIS_MODULE; ++ ++#define MAX_PORTS 8 ++static int ports[MAX_PORTS]; ++static int ports_c; ++#ifdef MODULE_PARM ++MODULE_PARM(ports, "1-" __MODULE_STRING(MAX_PORTS) "i"); ++#endif ++ ++#if 0 ++ #define DEBUGP printk ++#else ++ #define DEBUGP(format, args...) ++#endif ++ ++#define RTCP_SUPPORT ++ ++static int set_expected_rtp(struct ip_conntrack *ct, u_int32_t dstip, ++ u_int16_t dstport, unsigned int conntype) ++{ ++ struct ip_conntrack_expect expect, *exp = &expect; ++ struct ip_ct_sip_expect *exp_sip_info = &exp->help.exp_sip_info; ++ int ret = 0; ++ ++ memset(&expect, 0, sizeof(expect)); ++ LOCK_BH(&ip_sip_lock); ++ ++ DEBUGP("conntrack_sip: %s: [%s]: DST=%u.%u.%u.%u:%u\n", __FUNCTION__, ++ conntype == CONN_RTP ? "RTP" : "RTCP", NIPQUAD(dstip), dstport); ++ ++ /* exp_sip_info */ ++ exp_sip_info->port = dstport; ++ exp_sip_info->type = conntype; ++ exp_sip_info->nated = 0; ++ ++ /* new expectation */ ++ exp->tuple = ((struct ip_conntrack_tuple) ++ { { 0, { 0 } }, ++ { dstip, { htons(dstport) }, IPPROTO_UDP }}); ++ exp->mask = ((struct ip_conntrack_tuple) ++ { { 0, { 0 } }, ++ { 0xFFFFFFFF, { 0xFFFF }, 0xFFFF }}); ++ exp->expectfn = NULL; ++ ++ if ((ret=ip_conntrack_expect_related(ct, exp)) != 0) { ++ DEBUGP("Can't add new expectation. \n"); ++ } ++ ++ UNLOCK_BH(&ip_sip_lock); ++ ++ return ret; ++} ++ ++/* ++static int unset_expected_rtp(struct ip_conntrack *ct, u_int32_t dstip, u_int16_t dstport) ++{ ++ struct ip_conntrack_expect *exp; ++ const struct ip_conntrack_tuple tuple = { { 0, { 0 } }, ++ { dstip, { htons(dstport) }, IPPROTO_UDP }}; ++ ++ LOCK_BH(&ip_sip_lock); ++ ++ exp = ip_conntrack_expect_find_get(&tuple); ++ if (exp) { ++ DEBUGP("Find the expectation %p, then delete it.\n", exp); ++ ip_conntrack_unexpect_related(exp); ++ } ++ ++ UNLOCK_BH(&ip_sip_lock); ++ ++ return 0; ++}*/ ++ ++/* return: ++ * 0 : Not found ++ * 1 : Found domain name ++ * 2 : Found dotted quads ++ */ ++int find_sdp_rtp_addr(const char *data, size_t dlen, ++ unsigned int *numoff, unsigned int *numlen, u_int32_t *addr) ++{ ++ char *st, *p = (char *)data; ++ const char *limit = data + dlen; ++ unsigned char p1, p2, p3, p4; ++ ++ while (p < limit) { ++ /* find 'c=' line */ ++ if (strncmp(p, "\nc=",3) && strncmp(p, "\rc=",3)) { ++ p++; ++ continue; ++ } ++ p += 3; ++ ++ if (strncmp(p, "IN IP4 ",7)) ++ continue; ++ p += 7; ++ ++ /* IP address */ ++ st = p; ++ ++ /* FQDNs or dotted quads */ ++ while (isalpha(*p) || isdigit(*p) || (*p=='.') || (*p=='-')) { ++ p++; ++ if (p == limit) ++ return 0; ++ } ++ ++ *numoff = st - data; ++ *numlen = p - st; ++ ++ /* Convert the IP address */ ++ p1 = simple_strtoul(st, &st ,10); ++ if (*st != '.') ++ return 1; ++ p2 = simple_strtoul(st+1, &st, 10); ++ if (*st != '.') ++ return 1; ++ p3 = simple_strtoul(st+1, &st, 10); ++ if (*st != '.') ++ return 1; ++ p4 = simple_strtoul(st+1, &st, 10); ++ ++ *addr = (p1<<24) | (p2<<16) | (p3<<8) | p4; ++ ++ return 2; ++ } ++ ++ return 0; ++} ++ ++u_int16_t find_sdp_audio_port(const char *data, size_t dlen, ++ unsigned int *numoff, unsigned int *numlen) ++{ ++ char *st, *p = (char *)data; ++ const char *limit = data + dlen; ++ u_int16_t port = 0; ++ ++ while (p < limit) { ++ /* find 'm=' */ ++ if (strncmp(p, "\nm=", 3) && strncmp(p, "\rm=", 3)) { ++ p++; ++ continue; ++ } ++ p += 3; ++ ++ /* audio stream */ ++ if (strncmp(p ,"audio ",6)) ++ continue; ++ p += 6; ++ ++ st = p; ++ port = simple_strtoul(p, &p, 10); ++ ++ *numoff = st - data; ++ *numlen = p - st; ++ ++ return port; ++ } ++ ++ return 0; ++} ++ ++static int help(const struct iphdr *iph, size_t len, ++ struct ip_conntrack *ct, ++ enum ip_conntrack_info ctinfo) ++{ ++ int dir = CTINFO2DIR(ctinfo); ++ unsigned int matchlen, matchoff; ++ ++ u_int32_t ipaddr=0; ++ u_int16_t port = 0; ++ ++ int found = 0; ++ struct udphdr *udph = (void *)iph + iph->ihl * 4; ++ const char *data = (const char *)udph + 8; ++ unsigned int udplen = len - iph->ihl * 4; ++ unsigned int datalen = udplen - 8; ++ struct ip_ct_sip_master *ct_sip_info = &ct->help.ct_sip_info; ++ ++ DEBUGP("\nconntrack_sip: help(): DIR=%d, conntrackinfo=%u\n", dir, ctinfo); ++ DEBUGP("conntrack_sip: %u.%u.%u.%u:%u -> %u.%u.%u.%u:%u\n", ++ NIPQUAD(ct->tuplehash[dir].tuple.src.ip), ++ ntohs(ct->tuplehash[dir].tuple.src.u.udp.port), ++ NIPQUAD(ct->tuplehash[dir].tuple.dst.ip), ++ ntohs(ct->tuplehash[dir].tuple.dst.u.udp.port) ); ++ ++ /* Reset for a new incoming packet */ ++ ct_sip_info->mangled = 0; ++ ++ /* keep the connection alive */ ++ ip_ct_refresh(ct, (SIP_EXPIRES * HZ)); ++ ++ /* Don't need to set the expectation for upstream direction */ ++ if (dir == IP_CT_DIR_REPLY) ++ return NF_ACCEPT; ++ ++ /* Need to set the expected connection for further incoming RTP stream */ ++ if (strncmp(data, "INVITE", 6) != 0 && strncmp(data, "SIP/2.0 200", 11) != 0) { ++ DEBUGP("conntrack_sip: Not interesting packet.\n"); ++ return NF_ACCEPT; ++ } ++ ++ /* Find RTP address */ ++ found = find_sdp_rtp_addr(data, datalen, &matchoff, &matchlen, &ipaddr); ++ if (!found) ++ return NF_ACCEPT; ++ ++ DEBUGP("conntrack_sip: 'IN IP4' is %s.\n", (found == 1) ? "FQDNs" : "dotted quads"); ++ ++ /* If it's a null address, then the call is on hold */ ++ if (found == 2 && ipaddr == 0) { ++ DEBUGP("conntrack_sip: Null address is found.\n"); ++ return NF_ACCEPT; ++ } ++ ++ /* Find audio port, and we don't like the well-known ports, ++ * which is less than 1024 */ ++ port = find_sdp_audio_port(data, datalen, &matchoff, &matchlen); ++ if (port < 1024) ++ return NF_ACCEPT; ++ ++ DEBUGP("conntrack_sip: audio port=%d.\n", port); ++ ++ ipaddr = ct->tuplehash[dir].tuple.src.ip; ++ ct_sip_info->rtpport = port; ++ ++ /* RFC1889 - RTP uses an even port number and the corresponding RTCP ++ * stream uses the next higher (odd) port number. */ ++ if (set_expected_rtp(ct, ipaddr, port, CONN_RTP) == 0) { ++#ifdef RTCP_SUPPORT ++ set_expected_rtp(ct, ipaddr, port + 1, CONN_RTCP); ++#endif ++ } ++ ++ return NF_ACCEPT; ++} ++ ++static struct ip_conntrack_helper sip[MAX_PORTS]; ++ ++ ++/* Not __exit: called from init() */ ++static void fini(void) ++{ ++ int i; ++ for (i = 0; (i < MAX_PORTS) && ports[i]; i++) { ++ DEBUGP("ip_ct_sip: unregistering helper for port %d\n", ++ ports[i]); ++ ip_conntrack_helper_unregister(&sip[i]); ++ } ++} ++ ++static int __init init(void) ++{ ++ int i, ret; ++ ++ if (ports[0] == 0) ++ ports[0] = SIP_PORT; ++ ++ for (i = 0; (i < MAX_PORTS) && ports[i]; i++) { ++ memset(&sip[i], 0, sizeof(struct ip_conntrack_helper)); ++ sip[i].tuple.dst.u.udp.port = htons(ports[i]); ++ sip[i].tuple.dst.protonum = IPPROTO_UDP; ++ sip[i].mask.dst.u.udp.port = 0xF0FF; ++ sip[i].mask.dst.protonum = 0xFFFF; ++ sip[i].help = help; ++ sip[i].timeout = RTP_TIMEOUT; ++ DEBUGP("ip_ct_sip: registering helper for port %d\n", ++ ports[i]); ++ ret = ip_conntrack_helper_register(&sip[i]); ++ ++ if (ret) { ++ fini(); ++ return ret; ++ } ++ ports_c++; ++ } ++ return 0; ++} ++ ++ ++EXPORT_SYMBOL(ip_sip_lock); ++EXPORT_SYMBOL(ip_conntrack_sip); ++ ++module_init(init); ++module_exit(fini); +diff -urN linux-2.4.32/net/ipv4/netfilter/ip_nat_sip.c linux-2.4.32/net/ipv4/netfilter/ip_nat_sip.c +--- linux-2.4.32/net/ipv4/netfilter/ip_nat_sip.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-2.4.32/net/ipv4/netfilter/ip_nat_sip.c 2005-12-11 21:35:51.000000000 +0100 +@@ -0,0 +1,800 @@ ++/* ++ * SIP extension for TCP NAT alteration. ++ * ++ * Copyright (C) 2004, CyberTAN Corporation ++ * All Rights Reserved. ++ * ++ * THIS SOFTWARE IS OFFERED "AS IS", AND CYBERTAN GRANTS NO WARRANTIES OF ANY ++ * KIND, EXPRESS OR IMPLIED, BY STATUTE, COMMUNICATION OR OTHERWISE. CYBERTAN ++ * SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS ++ * FOR A SPECIFIC PURPOSE OR NONINFRINGEMENT CONCERNING THIS SOFTWARE. ++ * ++ */ ++ ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++ ++#if 0 ++ #define DEBUGP printk ++#else ++ #define DEBUGP(format, args...) ++#endif ++ ++#define MAX_PORTS 8 ++static int ports[MAX_PORTS]; ++static int ports_c = 0; ++ ++#ifdef MODULE_PARM ++MODULE_PARM(ports, "1-" __MODULE_STRING(MAX_PORTS) "i"); ++#endif ++ ++DECLARE_LOCK_EXTERN(ip_sip_lock); ++ ++#define RTCP_SUPPORT ++ ++/* down(stream): caller -> callee ++ up(stream): caller <- callee */ ++ ++ ++/* Return 1 for match, 0 for accept, -1 for partial. */ ++static int find_pattern(const char *data, size_t dlen, ++ const char *pattern, size_t plen, ++ char skip, char term, ++ unsigned int *numoff, ++ unsigned int *numlen ++ ) ++{ ++ size_t i, j, k; ++ ++// DEBUGP("find_pattern `%s': dlen = %u\n", pattern, dlen); ++ if (dlen == 0) ++ return 0; ++ ++ if (dlen <= plen) { ++ /* Short packet: try for partial? */ ++ if (strnicmp(data, pattern, dlen) == 0) ++ return -1; ++ else return 0; ++ } ++ ++ for(i=0; i<= (dlen - plen); i++){ ++ if( memcmp(data + i, pattern, plen ) != 0 ) continue; ++ ++ /* patten match !! */ ++ *numoff=i + plen; ++ for (j=*numoff, k=0; data[j] != term; j++, k++) ++ if( j > dlen ) return -1 ; /* no terminal char */ ++ ++ *numlen = k; ++ return 1; ++ } ++ ++ return 0; ++} ++ ++static unsigned int ++sip_nat_expected(struct sk_buff **pskb, ++ unsigned int hooknum, ++ struct ip_conntrack *ct, ++ struct ip_nat_info *info) ++{ ++ struct ip_nat_multi_range mr; ++ u_int32_t newdstip, newsrcip, newip; ++ struct ip_ct_sip_expect *exp_sip_info; ++ struct ip_conntrack *master = master_ct(ct); ++ ++ IP_NF_ASSERT(info); ++ IP_NF_ASSERT(master); ++ IP_NF_ASSERT(!(info->initialized & (1<master->help.exp_sip_info; ++ ++ LOCK_BH(&ip_sip_lock); ++ ++ /* Outer machine IP */ ++ newsrcip = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip; ++ /* Client (virtual) IP under NAT */ ++ newdstip = master->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip; ++ ++ UNLOCK_BH(&ip_sip_lock); ++ ++ if (HOOK2MANIP(hooknum) == IP_NAT_MANIP_SRC) ++ newip = newsrcip; ++ else ++ newip = newdstip; ++ ++ DEBUGP("sip_nat_expected: IP to %u.%u.%u.%u:%u\n", NIPQUAD(newip), ++ htons(exp_sip_info->port)); ++ ++ mr.rangesize = 1; ++ /* We don't want to manip the per-protocol, just the IPs... */ ++ mr.range[0].flags = IP_NAT_RANGE_MAP_IPS; ++ mr.range[0].min_ip = mr.range[0].max_ip = newip; ++ ++ /* ... unless we're doing a MANIP_DST, in which case, make ++ sure we map to the correct port */ ++ if (HOOK2MANIP(hooknum) == IP_NAT_MANIP_DST) { ++ mr.range[0].flags |= IP_NAT_RANGE_PROTO_SPECIFIED; ++ mr.range[0].min = mr.range[0].max ++ = ((union ip_conntrack_manip_proto) ++ { htons(exp_sip_info->port) }); ++ } ++ ++ return ip_nat_setup_info(ct, &mr, hooknum); ++} ++ ++static int _find_sip_via_addrport(const char *data, size_t dlen, ++ unsigned int *numoff, unsigned int *numlen) ++{ ++ const char *addr, *p = data; ++ const char *limit = data + dlen; ++ ++ while (p < limit) { ++ /* Find the topmost via tag */ ++ if (strnicmp(p, "\nvia:",5) && strnicmp(p, "\nv:",3) && ++ strnicmp(p, "\rvia:",5) && strnicmp(p, "\rv:",3)) { ++ p++; ++ continue; ++ } ++ ++ /* Look for UDP */ ++ while (*p!='U' && *p!='u') { ++ if (p == limit) ++ return 0; ++ p++; ++ } ++ p+= 3; ++ ++ if (p >= limit) ++ return 0; ++ ++ /* Skip a space */ ++ while (*p == ' '){ ++ if (p == limit) ++ return 0; ++ p++; ++ } ++ ++ /* IP address */ ++ addr = p; ++ ++ /* FQDNs or dotted quads */ ++ while (isalpha(*p) || isdigit(*p) || (*p=='.') || (*p=='-')) { ++ p++; ++ if (p == limit) ++ return 0; ++ } ++ ++ /* If there is a port number, skip it */ ++ if (*p == ':') { ++ p++; ++ if (p == limit) ++ return 0; ++ ++ while (isdigit(*p)) { ++ p++; ++ if (p == limit) ++ return 0; ++ } ++ } ++ ++ *numoff = addr - data; ++ *numlen = p - addr; ++ ++ return 1; ++ } ++ ++ return 0; /* Not found */ ++} ++ ++static int _mangle_sip_via(struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, ++ struct sk_buff **pskb, u_int32_t newip, u_int16_t newport, ++ unsigned int numoff, unsigned int numlen) ++{ ++ int buflen; ++ char buffer[sizeof("nnn.nnn.nnn.nnn:nnnnn")]; ++ ++ sprintf(buffer, "%u.%u.%u.%u:%u", NIPQUAD(newip), newport); ++ buflen = strlen(buffer); ++ ++ MUST_BE_LOCKED(&ip_sip_lock); ++ ++ if (!ip_nat_mangle_udp_packet(pskb, ct, ctinfo, numoff, ++ numlen, buffer, buflen) ) ++ return 0; ++ ++ DEBUGP("(SIP) Via is changed to %s.\n", buffer); ++ ++ return buflen - numlen; ++} ++ ++static int mangle_sip_via(struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, ++ struct sk_buff **pskb, u_int32_t newip, u_int16_t newport) ++{ ++ struct iphdr *iph = (*pskb)->nh.iph; ++ struct udphdr *udph = (void *)iph + iph->ihl * 4; ++ const char *data = (const char *)udph + 8; ++ unsigned int udplen = ntohs(iph->tot_len) - (iph->ihl * 4); ++ unsigned int datalen = udplen - 8; ++ unsigned int matchoff, matchlen; ++ ++ /* Find the topmost via tag */ ++ _find_sip_via_addrport(data , datalen, &matchoff, &matchlen); ++ return _mangle_sip_via(ct, ctinfo, pskb, newip, newport, ++ matchoff, matchlen); ++} ++ ++static int mangle_sip_contact(struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, ++ struct sk_buff **pskb, u_int32_t newip, u_int16_t newport) ++{ ++ struct iphdr *iph = (*pskb)->nh.iph; ++ struct udphdr *udph = (void *)iph + iph->ihl * 4; ++ const char *data = (const char *)udph + 8; ++ unsigned int udplen = ntohs(iph->tot_len) - (iph->ihl * 4); ++ unsigned int datalen = udplen - 8; ++ ++ int buflen, diff_len = 0; ++ char buffer[sizeof("nnn.nnn.nnn.nnn:nnnnn")]; ++ const char *uri, *addr, *p = data; ++ const char *limit = data + datalen; ++ ++ ++ while (p < limit) { ++ if (strnicmp(p, "\ncontact:", 9) && strnicmp(p, "\nm:", 3) && ++ strnicmp(p, "\rcontact:", 9) && strnicmp(p, "\rm:", 3)) { ++ p++; ++ continue; ++ } ++ ++ while (strnicmp(p, "sip:", 4)) { ++ if (p == limit) ++ return 0; ++ p++; ++ } ++ p += 4; ++ ++ /* If there is user info in the contact */ ++ uri = p; ++ ++ while (*p!='@' && *p!='>' && *p!=';' && *p!='\n' && *p!='\r' && *p!='?' && *p!=',') { ++ if (p == limit) ++ return 0; ++ p++; ++ } ++ ++ if (*p=='@') ++ p++; ++ else ++ p = uri; /* back to previous URI pointer */ ++ ++ /* IP address */ ++ addr = p; ++ ++ /* FQDNs or dotted quads */ ++ while (isalpha(*p) || isdigit(*p) || (*p=='.') || (*p=='-')) { ++ p++; ++ if (p == limit) ++ return 0; ++ } ++ ++ /* If there is a port number, skip it */ ++ if (*p==':') { ++ p++; ++ while (isdigit(*p)) ++ p++; ++ } ++ ++ sprintf(buffer, "%u.%u.%u.%u:%u", NIPQUAD(newip), newport); ++ buflen = strlen(buffer); ++ ++ MUST_BE_LOCKED(&ip_sip_lock); ++ ++ if (!ip_nat_mangle_udp_packet(pskb, ct, ctinfo, addr - data, ++ p - addr, buffer, buflen) ) ++ return 0; ++ ++ diff_len = buflen - (p - addr); ++ DEBUGP("(SIP) Contact is changed to %s.\n", buffer); ++ break; ++ } ++ ++ return diff_len; ++} ++ ++static int _find_sip_content_length_size(const char *data, size_t dlen, ++ unsigned int *numoff, unsigned int *numlen) ++{ ++ char *st, *p = (char *)data; ++ const char *limit = data + dlen; ++ int size = 0; ++ ++ while (p < limit) { ++ if (strnicmp(p, "\nContent-Length:", 16) && strnicmp(p, "\nl:", 3) && ++ strnicmp(p, "\rContent-Length:", 16) && strnicmp(p, "\rm:", 3)) { ++ p++; ++ continue; ++ } ++ ++ /* Go through the string above */ ++ while (*p != ':') { ++ if (p == limit) ++ return 0; ++ p++; ++ } ++ p++; ++ ++ while (*p == ' ') { ++ if (p == limit) ++ return 0; ++ p++; ++ } ++ ++ st = p; ++ size = simple_strtoul(p, &p, 10); ++ ++ *numoff = st - data; ++ *numlen = p - st; ++ ++ return size; ++ } ++ ++ return 0; ++} ++ ++static int mangle_sip_content_length(struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, ++ struct sk_buff **pskb, int diff_len) ++{ ++ struct iphdr *iph = (*pskb)->nh.iph; ++ struct udphdr *udph = (void *)iph + iph->ihl * 4; ++ const char *data = (const char *)udph + 8; ++ unsigned int udplen = ntohs(iph->tot_len) - (iph->ihl * 4); ++ unsigned int datalen = udplen - 8; ++ ++ unsigned int matchlen, matchoff; ++ int size, buflen; ++ char buffer[sizeof("nnnnn")]; ++ ++ /* original legth */ ++ size = _find_sip_content_length_size(data, datalen, &matchoff, &matchlen); ++ ++ /* new legth */ ++ sprintf(buffer, "%u", size + diff_len); ++ buflen = strlen(buffer); ++ ++ if (!ip_nat_mangle_udp_packet(pskb, ct, ctinfo, matchoff, ++ matchlen, buffer, buflen) ) ++ return 0; ++ ++ DEBUGP("(SDP) Content-Length is changed %d->%s.\n", size, buffer); ++ return buflen - matchlen; ++ ++} ++ ++static int mangle_sip_sdp_content(struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, ++ struct sk_buff **pskb, u_int32_t newip, u_int16_t newport) ++{ ++ struct iphdr *iph = (*pskb)->nh.iph; ++ struct udphdr *udph = (void *)iph + iph->ihl * 4; ++ const char *data = (const char *)udph + 8; ++ unsigned int udplen = ntohs(iph->tot_len) - (iph->ihl * 4); ++ unsigned int datalen = udplen - 8; ++ ++ unsigned int matchlen, matchoff; ++ int found, buflen, diff_len = 0; ++ char buffer[sizeof("nnn.nnn.nnn.nnn")]; ++ char *addr, *p; ++ char *limit = (char *)data + datalen; ++ u_int32_t ipaddr = 0; ++ u_int16_t getport; ++ int dir; ++ ++ /* Find RTP address */ ++ found = find_sdp_rtp_addr(data, datalen, &matchoff, &matchlen, &ipaddr); ++ if (found) { ++ /* If it's a null address, then the call is on hold */ ++ if (found == 2 && ipaddr == 0) ++ return 0; ++ ++ sprintf(buffer, "%u.%u.%u.%u", NIPQUAD(newip)); ++ buflen = strlen(buffer); ++ ++ MUST_BE_LOCKED(&ip_sip_lock); ++ ++ if (!ip_nat_mangle_udp_packet(pskb, ct, ctinfo, matchoff, ++ matchlen, buffer, buflen) ) ++ return 0; ++ ++ diff_len += (buflen - matchlen); ++ DEBUGP("(SDP) RTP address is changed to %s.\n", buffer); ++ } ++ ++ /* Find audio port */ ++ getport = find_sdp_audio_port(data, datalen, &matchoff, &matchlen); ++ if (getport != newport) { ++ sprintf(buffer, "%d", newport); ++ buflen = strlen(buffer); ++ ++ MUST_BE_LOCKED(&ip_sip_lock); ++ ++ if (!ip_nat_mangle_udp_packet(pskb, ct, ctinfo, matchoff, ++ matchlen, buffer, buflen) ) ++ return 0; ++ ++ diff_len += (buflen - matchlen); ++ DEBUGP("(SDP) audio port is changed to %d.\n", newport); ++ } ++ ++ dir = CTINFO2DIR(ctinfo); ++ if (dir == IP_CT_DIR_ORIGINAL) ++ return diff_len; ++ ++ /* Find Session ID address */ ++ found = find_pattern(data, datalen, " IN IP4 ", 8, ' ', '\r', ++ &matchoff, &matchlen); ++ if (found) { ++ p = addr = (char *)data + matchoff; ++ ++ /* FQDNs or dotted quads */ ++ while (isalpha(*p) || isdigit(*p) || (*p=='.') || (*p=='-')) { ++ p++; ++ if (p == limit) ++ return 0; ++ } ++ ++ sprintf(buffer, "%u.%u.%u.%u", NIPQUAD(newip)); ++ buflen = strlen(buffer); ++ ++ MUST_BE_LOCKED(&ip_sip_lock); ++ ++ if (!ip_nat_mangle_udp_packet(pskb, ct, ctinfo, addr - data, ++ p - addr, buffer, buflen) ) ++ return 0; ++ ++ diff_len += (buflen - (p - addr)); ++ DEBUGP("(SDP) Session ID is changed to %s.\n", buffer); ++ } ++ ++ return diff_len; ++} ++ ++static int mangle_sip_packet(struct ip_conntrack *ct, enum ip_conntrack_info ctinfo, ++ struct sk_buff **pskb, u_int32_t newip) ++{ ++ struct iphdr *iph = (*pskb)->nh.iph; ++ struct udphdr *udph = (void *)iph + iph->ihl * 4; ++ const char *data = (const char *)udph + 8; ++ int diff_len = 0; ++ struct ip_ct_sip_master *ct_sip_info = &ct->help.ct_sip_info; ++ u_int16_t natport = ntohs(ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u.udp.port); ++ ++ DEBUGP("nat_sip: %s:(%d)\n", __FUNCTION__, __LINE__); ++ ++ ct_sip_info->mangled = 1; ++ ++ /* Changes the via, if this is a request */ ++ if (strnicmp(data,"SIP/2.0",7) != 0) { ++ mangle_sip_via(ct, ctinfo, pskb, newip, natport); ++ } ++ ++ mangle_sip_contact(ct, ctinfo, pskb, newip, natport); ++ ++ if ((diff_len = mangle_sip_sdp_content(ct, ctinfo, pskb, newip, ct_sip_info->rtpport)) != 0) ++ mangle_sip_content_length(ct, ctinfo, pskb, diff_len); ++ ++ return 1; ++} ++ ++static struct ip_conntrack_expect * ++expect_find(struct ip_conntrack *ct, u_int32_t dstip, u_int16_t dstport) ++{ ++ const struct ip_conntrack_tuple tuple = { { 0, { 0 } }, ++ { dstip, { htons(dstport) }, IPPROTO_UDP }}; ++ ++ return ip_conntrack_expect_find_get(&tuple); ++ ++} ++ ++static int sip_out_data_fixup(struct ip_conntrack *ct, ++ struct sk_buff **pskb, ++ enum ip_conntrack_info ctinfo, ++ struct ip_conntrack_expect *expect) ++{ ++ struct ip_conntrack_tuple newtuple; ++ struct ip_ct_sip_master *ct_sip_info = &ct->help.ct_sip_info; ++ struct ip_ct_sip_expect *exp_sip_info; ++ u_int32_t wanip = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip; // NAT wan ip ++ u_int16_t port = 0; ++#ifdef RTCP_SUPPORT ++ struct ip_conntrack_expect *rtcp_exp; ++#endif ++ ++ MUST_BE_LOCKED(&ip_sip_lock); ++ ++ if (expect) { ++ DEBUGP("nat_sip: %s: There is a exp %p.\n", __FUNCTION__, expect); ++ ++ exp_sip_info = &expect->help.exp_sip_info; ++ if (exp_sip_info->nated) { ++ DEBUGP("nat_sip: %s: The exp %p had been changed.\n", __FUNCTION__, expect); ++ goto mangle; ++ } ++ ++ /* RTP expect */ ++ if (exp_sip_info->type == CONN_RTP) { ++ port = ntohs(expect->tuple.dst.u.udp.port); ++#ifdef RTCP_SUPPORT ++ rtcp_exp = expect_find(ct, expect->tuple.dst.ip, port + 1); ++#endif ++ /* RFC1889 - If an application is supplied with an odd number ++ * for use as the RTP port, it should replace this number with ++ * the next lower (even) number. */ ++ if (port % 2) ++ port++; ++ ++ /* fullfill newtuple */ ++ newtuple.dst.ip = wanip; ++ newtuple.src.ip = expect->tuple.src.ip; ++ newtuple.dst.protonum = expect->tuple.dst.protonum; ++ ++ /* Try to get same port: if not, try to change it. */ ++ for (; port != 0; port += 2) { ++ newtuple.dst.u.udp.port = htons(port); ++ if (ip_conntrack_change_expect(expect, &newtuple) == 0) { ++#ifdef RTCP_SUPPORT ++ /* Change RTCP */ ++ if (rtcp_exp) { ++ DEBUGP("nat_sip: %s: RTCP exp %p found.\n", ++ __FUNCTION__, rtcp_exp); ++ newtuple.dst.u.udp.port = htons(port + 1); ++ if (ip_conntrack_change_expect(rtcp_exp, &newtuple) != 0) { ++ DEBUGP("nat_sip: %s: Can't change RTCP exp %p.\n", ++ __FUNCTION__, rtcp_exp); ++ continue; ++ } ++ rtcp_exp->help.exp_sip_info.nated = 1; ++ } ++#endif ++ break; ++ } ++ } ++ if (port == 0) ++ return 0; ++ ++ exp_sip_info->nated = 1; ++ ct_sip_info->rtpport = port; ++ DEBUGP("nat_sip: %s: RTP exp %p, masq port=%d\n", __FUNCTION__, expect, port); ++ } ++#ifdef RTCP_SUPPORT ++ else { ++ /* We ignore the RTCP expect, and will adjust it later ++ * during RTP expect */ ++ DEBUGP("nat_sip: %s: RTCP exp %p, by-pass.\n", __FUNCTION__, expect); ++ return 1; ++ } ++#endif ++ } ++ ++mangle: ++ /* Change address inside packet to match way we're mapping ++ this connection. */ ++ if (!ct_sip_info->mangled) ++ if (!mangle_sip_packet(ct, ctinfo, pskb, wanip)) ++ return 0; ++ ++ return 1; ++} ++ ++static int sip_in_data_fixup(struct ip_conntrack *ct, ++ struct sk_buff **pskb, ++ enum ip_conntrack_info ctinfo, ++ struct ip_conntrack_expect *expect) ++{ ++ struct iphdr *iph = (*pskb)->nh.iph; ++ struct udphdr *udph = (void *)iph + iph->ihl * 4; ++ const char *data = (const char *)udph + 8; ++ unsigned int udplen = ntohs(iph->tot_len) - (iph->ihl * 4); ++ unsigned int datalen = udplen - 8; ++ struct ip_ct_sip_master *ct_sip_info = &ct->help.ct_sip_info; ++ u_int32_t wanip = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip; // NAT wan ip ++ unsigned int matchlen, matchoff; ++ int found, diff_len = 0; ++ u_int32_t ipaddr = 0, vip = 0; ++ u_int16_t port = 0, vport = 0, aport = 0; ++ struct ip_conntrack_expect *exp; ++#ifdef RTCP_SUPPORT ++ struct ip_conntrack_expect *rtcpexp; ++#endif ++ ++ if (expect) ++ DEBUGP("nat_sip: %s: There is a exp %p.\n", __FUNCTION__, expect); ++ ++ /* Prevent from mangling the packet or expect twice */ ++ if (ct_sip_info->mangled) ++ return 1; ++ ++ ct_sip_info->mangled = 1; ++ ++ if (strnicmp(data, "SIP/2.0 200", 11) == 0) { ++ /* Find CSeq field */ ++ found = find_pattern(data, datalen, "CSeq: ", 6, ' ', '\r', ++ &matchoff, &matchlen); ++ if (found) { ++ char *p = (char *)data + matchoff; ++ ++ simple_strtoul(p, &p, 10); ++ if (strnicmp(p, " REGISTER", 9) == 0) { ++ DEBUGP("nat_sip: 200 OK - REGISTER\n"); ++ vip = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip; ++ vport = ntohs(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.udp.port); ++ mangle_sip_via(ct, ctinfo, pskb, vip, vport); ++ mangle_sip_contact(ct, ctinfo, pskb, vip, vport); ++ return 1; ++ } ++ } ++ } ++ ++ /* Only interesting the SDP content. */ ++ if (strnicmp(data, "INVITE", 6) != 0 && strnicmp(data, "SIP/2.0 200", 11) != 0) ++ return 1; ++ ++ /* Find RTP address */ ++ found = find_sdp_rtp_addr(data, datalen, &matchoff, &matchlen, &ipaddr); ++ ++ DEBUGP("nat_sip: sdp address found = %d, ipaddr = %u.\n", found, ipaddr); ++ if (found < 2) ++ return 1; ++ ++ /* Is it a null address or our WAN address? */ ++ if (ipaddr == 0 || (htonl(ipaddr) != wanip)) ++ return 1; ++ ++ DEBUGP("nat_sip: %s: This is a lookback RTP connection.\n", __FUNCTION__); ++ ++ /* Find audio port, and we don't like the well-known ports, ++ * which is less than 1024 */ ++ port = find_sdp_audio_port(data, datalen, &matchoff, &matchlen); ++ if (port < 1024) ++ return 0; ++ ++ exp = expect_find(ct, wanip, port); ++ if (exp) { ++ DEBUGP("nat_sip: %s: Found exp %p, tuple.dst=%u.%u.%u.%u:%u.\n", ++ __FUNCTION__, exp, NIPQUAD(ipaddr), port); ++ ++ /* Restore masq-ed SDP */ ++ vip = exp->expectant->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip; ++ aport = exp->help.exp_sip_info.port; ++ if ((diff_len = mangle_sip_sdp_content(ct, ctinfo, pskb, vip, aport)) != 0) ++ mangle_sip_content_length(ct, ctinfo, pskb, diff_len); ++ ++ /* Unset RTP, RTCP expect, respectively */ ++ ip_conntrack_unexpect_related(exp); ++#ifdef RTCP_SUPPORT ++ rtcpexp = expect_find(ct, wanip, port + 1); ++ if (rtcpexp) ++ ip_conntrack_unexpect_related(rtcpexp); ++#endif ++ } ++ ++ return 1; ++} ++ ++static unsigned int nat_help(struct ip_conntrack *ct, ++ struct ip_conntrack_expect *exp, ++ struct ip_nat_info *info, ++ enum ip_conntrack_info ctinfo, ++ unsigned int hooknum, ++ struct sk_buff **pskb) ++{ ++ int dir; ++ struct iphdr *iph = (*pskb)->nh.iph; ++ struct udphdr *udph = (void *)iph + iph->ihl * 4; ++ const char *data = (const char *)udph + 8; ++ ++ /* Only mangle things once: original direction in POST_ROUTING ++ and reply direction on PRE_ROUTING. */ ++ dir = CTINFO2DIR(ctinfo); ++ if (!((hooknum == NF_IP_POST_ROUTING && dir == IP_CT_DIR_ORIGINAL) ++ || (hooknum == NF_IP_PRE_ROUTING && dir == IP_CT_DIR_REPLY))) { ++ DEBUGP("nat_sip: Not touching dir %s at hook %s\n", ++ dir == IP_CT_DIR_ORIGINAL ? "ORIG" : "REPLY", ++ hooknum == NF_IP_POST_ROUTING ? "POSTROUTING" ++ : hooknum == NF_IP_PRE_ROUTING ? "PREROUTING" ++ : hooknum == NF_IP_LOCAL_OUT ? "OUTPUT" : "???"); ++ return NF_ACCEPT; ++ } ++ ++ if (strnicmp(data, "REGISTER" , 8) == 0) ++ DEBUGP("nat_sip: REGISTER\n"); ++ else if (strnicmp(data, "INVITE" , 6) == 0) ++ DEBUGP("nat_sip: INVITE\n"); ++ else if (strnicmp(data, "ACK" , 3) == 0) ++ DEBUGP("nat_sip: ACK\n"); ++ else if (strnicmp(data, "BYE", 3) == 0) ++ DEBUGP("nat_sip: BYE\n"); ++ else if (strnicmp(data, "SIP/2.0 200", 11) == 0) ++ DEBUGP("nat_sip: 200 OK\n"); ++ else if (strnicmp(data, "SIP/2.0 100", 11) == 0) ++ DEBUGP("nat_sip: 100 Trying\n"); ++ else if (strnicmp(data, "SIP/2.0 180", 11) == 0) ++ DEBUGP("nat_sip: 180 Ringing\n"); ++ ++ LOCK_BH(&ip_sip_lock); ++ ++ if (dir == IP_CT_DIR_ORIGINAL) ++ sip_out_data_fixup(ct, pskb, ctinfo, exp); ++ else ++ sip_in_data_fixup(ct, pskb, ctinfo, exp); ++ ++ UNLOCK_BH(&ip_sip_lock); ++ ++ return NF_ACCEPT; ++} ++ ++static struct ip_nat_helper sip[MAX_PORTS]; ++static char sip_names[MAX_PORTS][6]; ++ ++/* Not __exit: called from init() */ ++static void fini(void) ++{ ++ int i; ++ ++ for (i = 0; (i < MAX_PORTS) && ports[i]; i++) { ++ DEBUGP("ip_nat_sip: unregistering port %d\n", ports[i]); ++ ip_nat_helper_unregister(&sip[i]); ++ } ++} ++ ++static int __init init(void) ++{ ++ int i, ret=0; ++ char *tmpname; ++ ++ if (ports[0] == 0) ++ ports[0] = SIP_PORT; ++ ++ for (i = 0; (i < MAX_PORTS) && ports[i]; i++) { ++ ++ memset(&sip[i], 0, sizeof(struct ip_nat_helper)); ++ ++ sip[i].tuple.dst.u.udp.port = htons(ports[i]); ++ sip[i].tuple.dst.protonum = IPPROTO_UDP; ++ sip[i].mask.dst.u.udp.port = 0xF0FF; ++ sip[i].mask.dst.protonum = 0xFFFF; ++ sip[i].help = nat_help; ++ sip[i].expect = sip_nat_expected; ++ sip[i].flags = IP_NAT_HELPER_F_ALWAYS; ++ ++ tmpname = &sip_names[i][0]; ++ sprintf(tmpname, "sip%2.2d", i); ++ sip[i].name = tmpname; ++ ++ DEBUGP("ip_nat_sip: Trying to register for port %d\n", ++ ports[i]); ++ ret = ip_nat_helper_register(&sip[i]); ++ ++ if (ret) { ++ printk("ip_nat_sip: error registering " ++ "helper for port %d\n", ports[i]); ++ fini(); ++ return ret; ++ } ++ ports_c++; ++ } ++ ++ return ret; ++} ++ ++module_init(init); ++module_exit(fini); +diff -urN linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack.h linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack.h +--- linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack.h 2005-12-11 21:34:32.000000000 +0100 ++++ linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack.h 2005-12-11 22:06:57.000000000 +0100 +@@ -71,6 +71,7 @@ + #include + #include + #include ++#include + + /* per expectation: application helper private data */ + union ip_conntrack_expect_help { +@@ -79,6 +80,7 @@ + struct ip_ct_ftp_expect exp_ftp_info; + struct ip_ct_irc_expect exp_irc_info; + struct ip_ct_pptp_expect exp_pptp_info; ++ struct ip_ct_sip_expect exp_sip_info; + + #ifdef CONFIG_IP_NF_NAT_NEEDED + union { +@@ -93,6 +95,7 @@ + struct ip_ct_ftp_master ct_ftp_info; + struct ip_ct_irc_master ct_irc_info; + struct ip_ct_pptp_master ct_pptp_info; ++ struct ip_ct_sip_master ct_sip_info; + }; + + #ifdef CONFIG_IP_NF_NAT_NEEDED +diff -urN linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack_sip.h linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack_sip.h +--- linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack_sip.h 1970-01-01 01:00:00.000000000 +0100 ++++ linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack_sip.h 2005-12-11 21:35:51.000000000 +0100 +@@ -0,0 +1,56 @@ ++#ifndef _IP_CONNTRACK_SIP_H ++#define _IP_CONNTRACK_SIP_H ++/* SIP tracking. */ ++ ++#ifdef __KERNEL__ ++ ++#include ++ ++/* Protects sip part of conntracks */ ++DECLARE_LOCK_EXTERN(ip_sip_lock); ++ ++#define SIP_PORT 5060 /* UDP */ ++#define SIP_EXPIRES 3600 /* seconds */ ++#define RTP_TIMEOUT 180 /* seconds */ ++ ++#endif /* __KERNEL__ */ ++ ++/* SIP Request */ ++#define SIP_INVITE 0x01 ++#define SIP_ACK 0x02 ++#define SIP_BYE 0x04 ++/* SIP Response */ ++#define SIP_100 0x10 ++#define SIP_200 0x20 ++#define SIP_200_BYE 0x40 ++/* SIP session direction */ ++#define SIP_OUTGOING 0 ++#define SIP_INCOMING 1 ++ ++enum ip_ct_conntype ++{ ++ CONN_SIP, ++ CONN_RTP, ++ CONN_RTCP, ++}; ++ ++/* This structure is per expected connection */ ++struct ip_ct_sip_expect ++{ ++ u_int16_t port; /* TCP port that was to be used */ ++ ++ enum ip_ct_conntype type; ++ int nated; ++}; ++ ++/* This structure exists only once per master */ ++struct ip_ct_sip_master { ++ int mangled; ++ u_int16_t rtpport; ++}; ++ ++extern u_int16_t find_sdp_audio_port(const char *data, size_t dlen, ++ unsigned int *numoff, unsigned int *numlen); ++extern int find_sdp_rtp_addr(const char *data, size_t dlen, ++ unsigned int *numoff, unsigned int *numlen, u_int32_t *addr); ++#endif /* _IP_CONNTRACK_SIP_H */