X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=net%2Fipv4%2Fnetfilter.c;h=07de855e2175ea1f40760c84388388d4676f30b0;hb=7fee226ad2397b635e2fd565a59ca3ae08a164cd;hp=4c637a1cbd23466934b0c4253b84325bce2eba56;hpb=3e3850e989c5d2eb1aab6f0fd9257759f0f4cbc6;p=safe%2Fjmp%2Flinux-2.6 diff --git a/net/ipv4/netfilter.c b/net/ipv4/netfilter.c index 4c637a1..07de855 100644 --- a/net/ipv4/netfilter.c +++ b/net/ipv4/netfilter.c @@ -1,147 +1,258 @@ /* IPv4 specific functions of netfilter core */ - -#include -#ifdef CONFIG_NETFILTER - #include #include #include - #include -#include -#include -#include +#include +#include #include #include #include +#include /* route_me_harder function, used by iptable_nat, iptable_mangle + ip_queue */ -int ip_route_me_harder(struct sk_buff **pskb) +int ip_route_me_harder(struct sk_buff *skb, unsigned addr_type) { - struct iphdr *iph = (*pskb)->nh.iph; + struct net *net = dev_net(skb_dst(skb)->dev); + const struct iphdr *iph = ip_hdr(skb); struct rtable *rt; struct flowi fl = {}; - struct dst_entry *odst; + unsigned long orefdst; unsigned int hh_len; + unsigned int type; + + type = inet_addr_type(net, iph->saddr); + if (skb->sk && inet_sk(skb->sk)->transparent) + type = RTN_LOCAL; + if (addr_type == RTN_UNSPEC) + addr_type = type; /* some non-standard hacks like ipt_REJECT.c:send_reset() can cause - * packets with foreign saddr to appear on the NF_IP_LOCAL_OUT hook. + * packets with foreign saddr to appear on the NF_INET_LOCAL_OUT hook. */ - if (inet_addr_type(iph->saddr) == RTN_LOCAL) { + if (addr_type == RTN_LOCAL) { fl.nl_u.ip4_u.daddr = iph->daddr; - fl.nl_u.ip4_u.saddr = iph->saddr; + if (type == RTN_LOCAL) + fl.nl_u.ip4_u.saddr = iph->saddr; fl.nl_u.ip4_u.tos = RT_TOS(iph->tos); - fl.oif = (*pskb)->sk ? (*pskb)->sk->sk_bound_dev_if : 0; -#ifdef CONFIG_IP_ROUTE_FWMARK - fl.nl_u.ip4_u.fwmark = (*pskb)->nfmark; -#endif - if (ip_route_output_key(&rt, &fl) != 0) + fl.oif = skb->sk ? skb->sk->sk_bound_dev_if : 0; + fl.mark = skb->mark; + fl.flags = skb->sk ? inet_sk_flowi_flags(skb->sk) : 0; + if (ip_route_output_key(net, &rt, &fl) != 0) return -1; /* Drop old route. */ - dst_release((*pskb)->dst); - (*pskb)->dst = &rt->u.dst; + skb_dst_drop(skb); + skb_dst_set(skb, &rt->u.dst); } else { /* non-local src, find valid iif to satisfy * rp-filter when calling ip_route_input. */ fl.nl_u.ip4_u.daddr = iph->saddr; - if (ip_route_output_key(&rt, &fl) != 0) + if (ip_route_output_key(net, &rt, &fl) != 0) return -1; - odst = (*pskb)->dst; - if (ip_route_input(*pskb, iph->daddr, iph->saddr, + orefdst = skb->_skb_refdst; + if (ip_route_input(skb, iph->daddr, iph->saddr, RT_TOS(iph->tos), rt->u.dst.dev) != 0) { dst_release(&rt->u.dst); return -1; } dst_release(&rt->u.dst); - dst_release(odst); + refdst_drop(orefdst); } - - if ((*pskb)->dst->error) + + if (skb_dst(skb)->error) return -1; #ifdef CONFIG_XFRM - if (!(IPCB(*pskb)->flags & IPSKB_XFRM_TRANSFORMED) && - xfrm_decode_session(*pskb, &fl, AF_INET) == 0) - if (xfrm_lookup(&(*pskb)->dst, &fl, (*pskb)->sk, 0)) + if (!(IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) && + xfrm_decode_session(skb, &fl, AF_INET) == 0) { + struct dst_entry *dst = skb_dst(skb); + skb_dst_set(skb, NULL); + if (xfrm_lookup(net, &dst, &fl, skb->sk, 0)) return -1; + skb_dst_set(skb, dst); + } #endif /* Change in oif may mean change in hh_len. */ - hh_len = (*pskb)->dst->dev->hard_header_len; - if (skb_headroom(*pskb) < hh_len) { - struct sk_buff *nskb; - - nskb = skb_realloc_headroom(*pskb, hh_len); - if (!nskb) - return -1; - if ((*pskb)->sk) - skb_set_owner_w(nskb, (*pskb)->sk); - kfree_skb(*pskb); - *pskb = nskb; - } + hh_len = skb_dst(skb)->dev->hard_header_len; + if (skb_headroom(skb) < hh_len && + pskb_expand_head(skb, hh_len - skb_headroom(skb), 0, GFP_ATOMIC)) + return -1; return 0; } EXPORT_SYMBOL(ip_route_me_harder); +#ifdef CONFIG_XFRM +int ip_xfrm_me_harder(struct sk_buff *skb) +{ + struct flowi fl; + unsigned int hh_len; + struct dst_entry *dst; + + if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) + return 0; + if (xfrm_decode_session(skb, &fl, AF_INET) < 0) + return -1; + + dst = skb_dst(skb); + if (dst->xfrm) + dst = ((struct xfrm_dst *)dst)->route; + dst_hold(dst); + + if (xfrm_lookup(dev_net(dst->dev), &dst, &fl, skb->sk, 0) < 0) + return -1; + + skb_dst_drop(skb); + skb_dst_set(skb, dst); + + /* Change in oif may mean change in hh_len. */ + hh_len = skb_dst(skb)->dev->hard_header_len; + if (skb_headroom(skb) < hh_len && + pskb_expand_head(skb, hh_len - skb_headroom(skb), 0, GFP_ATOMIC)) + return -1; + return 0; +} +EXPORT_SYMBOL(ip_xfrm_me_harder); +#endif + +void (*ip_nat_decode_session)(struct sk_buff *, struct flowi *); +EXPORT_SYMBOL(ip_nat_decode_session); + /* * Extra routing may needed on local out, as the QUEUE target never * returns control to the table. */ struct ip_rt_info { - u_int32_t daddr; - u_int32_t saddr; + __be32 daddr; + __be32 saddr; u_int8_t tos; + u_int32_t mark; }; -static void queue_save(const struct sk_buff *skb, struct nf_info *info) +static void nf_ip_saveroute(const struct sk_buff *skb, + struct nf_queue_entry *entry) { - struct ip_rt_info *rt_info = nf_info_reroute(info); + struct ip_rt_info *rt_info = nf_queue_entry_reroute(entry); - if (info->hook == NF_IP_LOCAL_OUT) { - const struct iphdr *iph = skb->nh.iph; + if (entry->hook == NF_INET_LOCAL_OUT) { + const struct iphdr *iph = ip_hdr(skb); rt_info->tos = iph->tos; rt_info->daddr = iph->daddr; rt_info->saddr = iph->saddr; + rt_info->mark = skb->mark; } } -static int queue_reroute(struct sk_buff **pskb, const struct nf_info *info) +static int nf_ip_reroute(struct sk_buff *skb, + const struct nf_queue_entry *entry) { - const struct ip_rt_info *rt_info = nf_info_reroute(info); + const struct ip_rt_info *rt_info = nf_queue_entry_reroute(entry); - if (info->hook == NF_IP_LOCAL_OUT) { - struct iphdr *iph = (*pskb)->nh.iph; + if (entry->hook == NF_INET_LOCAL_OUT) { + const struct iphdr *iph = ip_hdr(skb); - if (!(iph->tos == rt_info->tos - && iph->daddr == rt_info->daddr - && iph->saddr == rt_info->saddr)) - return ip_route_me_harder(pskb); + if (!(iph->tos == rt_info->tos && + skb->mark == rt_info->mark && + iph->daddr == rt_info->daddr && + iph->saddr == rt_info->saddr)) + return ip_route_me_harder(skb, RTN_UNSPEC); } return 0; } -static struct nf_queue_rerouter ip_reroute = { - .rer_size = sizeof(struct ip_rt_info), - .save = queue_save, - .reroute = queue_reroute, +__sum16 nf_ip_checksum(struct sk_buff *skb, unsigned int hook, + unsigned int dataoff, u_int8_t protocol) +{ + const struct iphdr *iph = ip_hdr(skb); + __sum16 csum = 0; + + switch (skb->ip_summed) { + case CHECKSUM_COMPLETE: + if (hook != NF_INET_PRE_ROUTING && hook != NF_INET_LOCAL_IN) + break; + if ((protocol == 0 && !csum_fold(skb->csum)) || + !csum_tcpudp_magic(iph->saddr, iph->daddr, + skb->len - dataoff, protocol, + skb->csum)) { + skb->ip_summed = CHECKSUM_UNNECESSARY; + break; + } + /* fall through */ + case CHECKSUM_NONE: + if (protocol == 0) + skb->csum = 0; + else + skb->csum = csum_tcpudp_nofold(iph->saddr, iph->daddr, + skb->len - dataoff, + protocol, 0); + csum = __skb_checksum_complete(skb); + } + return csum; +} +EXPORT_SYMBOL(nf_ip_checksum); + +static __sum16 nf_ip_checksum_partial(struct sk_buff *skb, unsigned int hook, + unsigned int dataoff, unsigned int len, + u_int8_t protocol) +{ + const struct iphdr *iph = ip_hdr(skb); + __sum16 csum = 0; + + switch (skb->ip_summed) { + case CHECKSUM_COMPLETE: + if (len == skb->len - dataoff) + return nf_ip_checksum(skb, hook, dataoff, protocol); + /* fall through */ + case CHECKSUM_NONE: + skb->csum = csum_tcpudp_nofold(iph->saddr, iph->daddr, protocol, + skb->len - dataoff, 0); + skb->ip_summed = CHECKSUM_NONE; + csum = __skb_checksum_complete_head(skb, dataoff + len); + if (!csum) + skb->ip_summed = CHECKSUM_UNNECESSARY; + } + return csum; +} + +static int nf_ip_route(struct dst_entry **dst, struct flowi *fl) +{ + return ip_route_output_key(&init_net, (struct rtable **)dst, fl); +} + +static const struct nf_afinfo nf_ip_afinfo = { + .family = AF_INET, + .checksum = nf_ip_checksum, + .checksum_partial = nf_ip_checksum_partial, + .route = nf_ip_route, + .saveroute = nf_ip_saveroute, + .reroute = nf_ip_reroute, + .route_key_size = sizeof(struct ip_rt_info), }; -static int init(void) +static int ipv4_netfilter_init(void) { - return nf_register_queue_rerouter(PF_INET, &ip_reroute); + return nf_register_afinfo(&nf_ip_afinfo); } -static void fini(void) +static void ipv4_netfilter_fini(void) { - nf_unregister_queue_rerouter(PF_INET); + nf_unregister_afinfo(&nf_ip_afinfo); } -module_init(init); -module_exit(fini); +module_init(ipv4_netfilter_init); +module_exit(ipv4_netfilter_fini); -#endif /* CONFIG_NETFILTER */ +#ifdef CONFIG_SYSCTL +struct ctl_path nf_net_ipv4_netfilter_sysctl_path[] = { + { .procname = "net", }, + { .procname = "ipv4", }, + { .procname = "netfilter", }, + { } +}; +EXPORT_SYMBOL_GPL(nf_net_ipv4_netfilter_sysctl_path); +#endif /* CONFIG_SYSCTL */