static unsigned int ip_nat_fn(unsigned int hooknum, struct sk_buff **pskb, const struct net_device *in, const struct net_device *out, int (*okfn)(struct sk_buff *)) { struct ip_conntrack *ct; enum ip_conntrack_info ctinfo; struct ip_nat_info *info; /* maniptype == SRC for postrouting. */ enum ip_nat_manip_type maniptype = HOOK2MANIP(hooknum); /* jimmy added 20080324 */ struct sip_rtp_binding *sip_rtp_binding_tmp = NULL; /* --------------------------------- */ /* We never see fragments: conntrack defrags on pre-routing and local-out, and ip_nat_out protects post-routing. */ IP_NF_ASSERT(!((*pskb)->nh.iph->frag_off & htons(IP_MF|IP_OFFSET))); /* If we had a hardware checksum before, it's now invalid */ if ((*pskb)->ip_summed == CHECKSUM_HW) if (skb_checksum_help(*pskb, (out == NULL))) return NF_DROP; ct = ip_conntrack_get(*pskb, &ctinfo); /* Can't track? It's not due to stress, or conntrack would have dropped it. Hence it's the user's responsibilty to packet filter it out, or implement conntrack/NAT for that protocol. 8) --RR */ if (!ct) { /* Exception: ICMP redirect to new connection (not in hash table yet). We must not let this through, in case we're doing NAT to the same network. */ if ((*pskb)->nh.iph->protocol == IPPROTO_ICMP) { struct icmphdr _hdr, *hp; hp = skb_header_pointer(*pskb, (*pskb)->nh.iph->ihl*4, sizeof(_hdr), &_hdr); if (hp != NULL && hp->type == ICMP_REDIRECT) return NF_DROP; } return NF_ACCEPT; } /* Don't try to NAT if this packet is not conntracked */ if (ct == &ip_conntrack_untracked) return NF_ACCEPT; switch (ctinfo) { case IP_CT_RELATED: case IP_CT_RELATED+IP_CT_IS_REPLY: if ((*pskb)->nh.iph->protocol == IPPROTO_ICMP) { if (!ip_nat_icmp_reply_translation(pskb, ct, maniptype, CTINFO2DIR(ctinfo))) return NF_DROP; else return NF_ACCEPT; } /* Fall thru... (Only ICMPs can be IP_CT_IS_REPLY) */ case IP_CT_NEW: info = &ct->nat.info; /* Seen it before? This can happen for loopback, retrans, or local packets.. */ if (!ip_nat_initialized(ct, maniptype)) { unsigned int ret; if (unlikely(is_confirmed(ct))) /* NAT module was loaded late */ ret = alloc_null_binding_confirmed(ct, info, hooknum); else if (hooknum == NF_IP_LOCAL_IN) /* LOCAL_IN hook doesn't have a chain! */ ret = alloc_null_binding(ct, info, hooknum); else{ ret = ip_nat_rule_find(pskb, hooknum, in, out, ct, info); /* jimmy added 20080324 */ if((hooknum == NF_IP_POST_ROUTING) && ((*pskb)->nh.iph->protocol == IPPROTO_UDP)){ sip_rtp_binding_tmp = sip_rtp_binding_find(ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.ip, ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip); if(sip_rtp_binding_tmp){ /* jimmy added 20080328, for avoid sip pattern 100 run through in */ if( sip_rtp_binding_tmp->wan_uac_port && (ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.u.all == sip_rtp_binding_tmp->wan_uac_port)){ /* ----------------------------------------------- */ if(sip_rtp_binding_tmp->router_port && sip_rtp_binding_tmp->router_ip && (sip_rtp_binding_tmp->router_ip == ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip) && (sip_rtp_binding_tmp->router_port != ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u.all)){ write_lock_bh(&ip_conntrack_lock); ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u.all = sip_rtp_binding_tmp->router_port; write_unlock_bh(&ip_conntrack_lock); DEBUGP("After modified conntrack for sip incoming conntrack hash, this ct are\n"); DEBUGP("[IP_CT_DIR_REPLY] : %u %u.%u.%u.%u:%hu -> %u.%u.%u.%u:%hu\n", ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.protonum, NIPQUAD(ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.ip), ntohs(ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.u.all), NIPQUAD(ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip), ntohs(ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u.all)); DEBUGP("[IP_CT_DIR_ORIGINAL] : %u %u.%u.%u.%u:%hu -> %u.%u.%u.%u:%hu\n", ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum, NIPQUAD(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip), ntohs(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.all), NIPQUAD(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.ip), ntohs(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u.all)); } /* jimmy added 20080328, for avoid sip pattern 100 */ } /* ----------------------------------------------- */ } } /* ---------------------- */ } if (ret != NF_ACCEPT) { return ret; } } else DEBUGP("Already setup manip %s for ct %p\n", maniptype == IP_NAT_MANIP_SRC ? "SRC" : "DST", ct); break; default: /* ESTABLISHED */ IP_NF_ASSERT(ctinfo == IP_CT_ESTABLISHED || ctinfo == (IP_CT_ESTABLISHED+IP_CT_IS_REPLY)); info = &ct->nat.info; } IP_NF_ASSERT(info); return ip_nat_packet(ct, ctinfo, hooknum, pskb); }
static unsigned int ip_nat_fn(unsigned int hooknum, struct sk_buff **pskb, const struct net_device *in, const struct net_device *out, int (*okfn)(struct sk_buff *)) { struct ip_conntrack *ct; enum ip_conntrack_info ctinfo; struct ip_nat_info *info; /* maniptype == SRC for postrouting. */ enum ip_nat_manip_type maniptype = HOOK2MANIP(hooknum); /* We never see fragments: conntrack defrags on pre-routing and local-out, and ip_nat_out protects post-routing. */ IP_NF_ASSERT(!((*pskb)->nh.iph->frag_off & htons(IP_MF|IP_OFFSET))); ct = ip_conntrack_get(*pskb, &ctinfo); /* Can't track? It's not due to stress, or conntrack would have dropped it. Hence it's the user's responsibilty to packet filter it out, or implement conntrack/NAT for that protocol. 8) --RR */ if (!ct) { /* Exception: ICMP redirect to new connection (not in hash table yet). We must not let this through, in case we're doing NAT to the same network. */ if ((*pskb)->nh.iph->protocol == IPPROTO_ICMP) { struct icmphdr _hdr, *hp; hp = skb_header_pointer(*pskb, (*pskb)->nh.iph->ihl*4, sizeof(_hdr), &_hdr); if (hp != NULL && hp->type == ICMP_REDIRECT) { if (LOG_INVALID(IPPROTO_ICMP)) nf_log_packet(PF_INET, 0, *pskb, NULL, NULL, NULL, "ip_nat_fn: " "untracked ICMP redirect "); return NF_DROP; } } return NF_ACCEPT; } /* Don't try to NAT if this packet is not conntracked */ if (ct == &ip_conntrack_untracked) return NF_ACCEPT; switch (ctinfo) { case IP_CT_RELATED: case IP_CT_RELATED+IP_CT_IS_REPLY: if ((*pskb)->nh.iph->protocol == IPPROTO_ICMP) { if (!ip_nat_icmp_reply_translation(ct, ctinfo, hooknum, pskb)) return NF_DROP; else return NF_ACCEPT; } /* Fall thru... (Only ICMPs can be IP_CT_IS_REPLY) */ case IP_CT_NEW: info = &ct->nat.info; /* Seen it before? This can happen for loopback, retrans, or local packets.. */ if (!ip_nat_initialized(ct, maniptype)) { unsigned int ret; if (unlikely(is_confirmed(ct))) /* NAT module was loaded late */ ret = alloc_null_binding_confirmed(ct, info, hooknum); else if (hooknum == NF_IP_LOCAL_IN) /* LOCAL_IN hook doesn't have a chain! */ ret = alloc_null_binding(ct, info, hooknum); else ret = ip_nat_rule_find(pskb, hooknum, in, out, ct, info); if (ret != NF_ACCEPT) { return ret; } } else DEBUGP("Already setup manip %s for ct %p\n", maniptype == IP_NAT_MANIP_SRC ? "SRC" : "DST", ct); break; default: /* ESTABLISHED */ IP_NF_ASSERT(ctinfo == IP_CT_ESTABLISHED || ctinfo == (IP_CT_ESTABLISHED+IP_CT_IS_REPLY)); info = &ct->nat.info; } IP_NF_ASSERT(info); return ip_nat_packet(ct, ctinfo, hooknum, pskb); }
static unsigned int ip_nat_fn(unsigned int hooknum, struct sk_buff **pskb, const struct net_device *in, const struct net_device *out, int (*okfn)(struct sk_buff *)) { struct ip_conntrack *ct; enum ip_conntrack_info ctinfo; struct ip_nat_info *info; /* maniptype == SRC for postrouting. */ enum ip_nat_manip_type maniptype = HOOK2MANIP(hooknum); /* We never see fragments: conntrack defrags on pre-routing and local-out, and ip_nat_out protects post-routing. */ IP_NF_ASSERT(!((*pskb)->nh.iph->frag_off & htons(IP_MF|IP_OFFSET))); (*pskb)->nfcache |= NFC_UNKNOWN; /* If we had a hardware checksum before, it's now invalid */ if ((*pskb)->ip_summed == CHECKSUM_HW) (*pskb)->ip_summed = CHECKSUM_NONE; ct = ip_conntrack_get(*pskb, &ctinfo); /* Can't track? It's not due to stress, or conntrack would have dropped it. Hence it's the user's responsibilty to packet filter it out, or implement conntrack/NAT for that protocol. 8) --RR */ if (!ct) { /* Exception: ICMP redirect to new connection (not in hash table yet). We must not let this through, in case we're doing NAT to the same network. */ struct iphdr *iph = (*pskb)->nh.iph; struct icmphdr *hdr = (struct icmphdr *) ((u_int32_t *)iph + iph->ihl); if (iph->protocol == IPPROTO_ICMP && hdr->type == ICMP_REDIRECT) return NF_DROP; return NF_ACCEPT; } switch (ctinfo) { case IP_CT_RELATED: case IP_CT_RELATED+IP_CT_IS_REPLY: if ((*pskb)->nh.iph->protocol == IPPROTO_ICMP) { return icmp_reply_translation(*pskb, ct, hooknum, CTINFO2DIR(ctinfo)); } /* Fall thru... (Only ICMPs can be IP_CT_IS_REPLY) */ case IP_CT_NEW: info = &ct->nat.info; WRITE_LOCK(&ip_nat_lock); /* Seen it before? This can happen for loopback, retrans, or local packets.. */ if (!(info->initialized & (1 << maniptype))) { unsigned int ret; if (ct->master && master_ct(ct)->nat.info.helper && master_ct(ct)->nat.info.helper->expect) { ret = call_expect(master_ct(ct), pskb, hooknum, ct, info); } else { if (unlikely(is_confirmed(ct))) /* NAT module was loaded late */ ret = alloc_null_binding_confirmed(ct, info, hooknum); else if (hooknum == NF_IP_LOCAL_IN) /* LOCAL_IN hook doesn't have a chain */ ret = alloc_null_binding(ct, info, hooknum); else ret = ip_nat_rule_find(pskb, hooknum, in, out, ct, info); } if (ret != NF_ACCEPT) { WRITE_UNLOCK(&ip_nat_lock); return ret; } } else DEBUGP("Already setup manip %s for ct %p\n", maniptype == IP_NAT_MANIP_SRC ? "SRC" : "DST", ct); WRITE_UNLOCK(&ip_nat_lock); break; default: /* ESTABLISHED */ IP_NF_ASSERT(ctinfo == IP_CT_ESTABLISHED || ctinfo == (IP_CT_ESTABLISHED+IP_CT_IS_REPLY)); info = &ct->nat.info; } IP_NF_ASSERT(info); return do_bindings(ct, ctinfo, info, hooknum, pskb); }