diff options
Diffstat (limited to 'net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c')
-rw-r--r-- | net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c | 472 |
1 files changed, 0 insertions, 472 deletions
diff --git a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c deleted file mode 100644 index 9db988f9a4d7..000000000000 --- a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c +++ /dev/null @@ -1,472 +0,0 @@ - -/* (C) 1999-2001 Paul `Rusty' Russell - * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org> - * (C) 2006-2012 Patrick McHardy <kaber@trash.net> - * - * 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/types.h> -#include <linux/ip.h> -#include <linux/netfilter.h> -#include <linux/module.h> -#include <linux/skbuff.h> -#include <linux/icmp.h> -#include <linux/sysctl.h> -#include <net/route.h> -#include <net/ip.h> - -#include <linux/netfilter_ipv4.h> -#include <net/netfilter/nf_conntrack.h> -#include <net/netfilter/nf_conntrack_helper.h> -#include <net/netfilter/nf_conntrack_l4proto.h> -#include <net/netfilter/nf_conntrack_l3proto.h> -#include <net/netfilter/nf_conntrack_zones.h> -#include <net/netfilter/nf_conntrack_core.h> -#include <net/netfilter/nf_conntrack_seqadj.h> -#include <net/netfilter/ipv4/nf_conntrack_ipv4.h> -#include <net/netfilter/nf_nat_helper.h> -#include <net/netfilter/ipv4/nf_defrag_ipv4.h> -#include <net/netfilter/nf_log.h> - -static int conntrack4_net_id __read_mostly; -static DEFINE_MUTEX(register_ipv4_hooks); - -struct conntrack4_net { - unsigned int users; -}; - -static bool ipv4_pkt_to_tuple(const struct sk_buff *skb, unsigned int nhoff, - struct nf_conntrack_tuple *tuple) -{ - const __be32 *ap; - __be32 _addrs[2]; - ap = skb_header_pointer(skb, nhoff + offsetof(struct iphdr, saddr), - sizeof(u_int32_t) * 2, _addrs); - if (ap == NULL) - return false; - - tuple->src.u3.ip = ap[0]; - tuple->dst.u3.ip = ap[1]; - - return true; -} - -static bool ipv4_invert_tuple(struct nf_conntrack_tuple *tuple, - const struct nf_conntrack_tuple *orig) -{ - tuple->src.u3.ip = orig->dst.u3.ip; - tuple->dst.u3.ip = orig->src.u3.ip; - - return true; -} - -static int ipv4_get_l4proto(const struct sk_buff *skb, unsigned int nhoff, - unsigned int *dataoff, u_int8_t *protonum) -{ - const struct iphdr *iph; - struct iphdr _iph; - - iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph); - if (iph == NULL) - return -NF_ACCEPT; - - /* Conntrack defragments packets, we might still see fragments - * inside ICMP packets though. */ - if (iph->frag_off & htons(IP_OFFSET)) - return -NF_ACCEPT; - - *dataoff = nhoff + (iph->ihl << 2); - *protonum = iph->protocol; - - /* Check bogus IP headers */ - if (*dataoff > skb->len) { - pr_debug("nf_conntrack_ipv4: bogus IPv4 packet: " - "nhoff %u, ihl %u, skblen %u\n", - nhoff, iph->ihl << 2, skb->len); - return -NF_ACCEPT; - } - - return NF_ACCEPT; -} - -static unsigned int ipv4_helper(void *priv, - struct sk_buff *skb, - const struct nf_hook_state *state) -{ - struct nf_conn *ct; - enum ip_conntrack_info ctinfo; - const struct nf_conn_help *help; - const struct nf_conntrack_helper *helper; - - /* This is where we call the helper: as the packet goes out. */ - ct = nf_ct_get(skb, &ctinfo); - if (!ct || ctinfo == IP_CT_RELATED_REPLY) - return NF_ACCEPT; - - help = nfct_help(ct); - if (!help) - return NF_ACCEPT; - - /* rcu_read_lock()ed by nf_hook_thresh */ - helper = rcu_dereference(help->helper); - if (!helper) - return NF_ACCEPT; - - return helper->help(skb, skb_network_offset(skb) + ip_hdrlen(skb), - ct, ctinfo); -} - -static unsigned int ipv4_confirm(void *priv, - struct sk_buff *skb, - const struct nf_hook_state *state) -{ - struct nf_conn *ct; - enum ip_conntrack_info ctinfo; - - ct = nf_ct_get(skb, &ctinfo); - if (!ct || ctinfo == IP_CT_RELATED_REPLY) - goto out; - - /* adjust seqs for loopback traffic only in outgoing direction */ - if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) && - !nf_is_loopback_packet(skb)) { - if (!nf_ct_seq_adjust(skb, ct, ctinfo, ip_hdrlen(skb))) { - NF_CT_STAT_INC_ATOMIC(nf_ct_net(ct), drop); - return NF_DROP; - } - } -out: - /* We've seen it coming out the other side: confirm it */ - return nf_conntrack_confirm(skb); -} - -static unsigned int ipv4_conntrack_in(void *priv, - struct sk_buff *skb, - const struct nf_hook_state *state) -{ - return nf_conntrack_in(state->net, PF_INET, state->hook, skb); -} - -static unsigned int ipv4_conntrack_local(void *priv, - struct sk_buff *skb, - const struct nf_hook_state *state) -{ - if (ip_is_fragment(ip_hdr(skb))) { /* IP_NODEFRAG setsockopt set */ - enum ip_conntrack_info ctinfo; - struct nf_conn *tmpl; - - tmpl = nf_ct_get(skb, &ctinfo); - if (tmpl && nf_ct_is_template(tmpl)) { - /* when skipping ct, clear templates to avoid fooling - * later targets/matches - */ - skb->_nfct = 0; - nf_ct_put(tmpl); - } - return NF_ACCEPT; - } - - return nf_conntrack_in(state->net, PF_INET, state->hook, skb); -} - -/* Connection tracking may drop packets, but never alters them, so - make it the first hook. */ -static const struct nf_hook_ops ipv4_conntrack_ops[] = { - { - .hook = ipv4_conntrack_in, - .pf = NFPROTO_IPV4, - .hooknum = NF_INET_PRE_ROUTING, - .priority = NF_IP_PRI_CONNTRACK, - }, - { - .hook = ipv4_conntrack_local, - .pf = NFPROTO_IPV4, - .hooknum = NF_INET_LOCAL_OUT, - .priority = NF_IP_PRI_CONNTRACK, - }, - { - .hook = ipv4_helper, - .pf = NFPROTO_IPV4, - .hooknum = NF_INET_POST_ROUTING, - .priority = NF_IP_PRI_CONNTRACK_HELPER, - }, - { - .hook = ipv4_confirm, - .pf = NFPROTO_IPV4, - .hooknum = NF_INET_POST_ROUTING, - .priority = NF_IP_PRI_CONNTRACK_CONFIRM, - }, - { - .hook = ipv4_helper, - .pf = NFPROTO_IPV4, - .hooknum = NF_INET_LOCAL_IN, - .priority = NF_IP_PRI_CONNTRACK_HELPER, - }, - { - .hook = ipv4_confirm, - .pf = NFPROTO_IPV4, - .hooknum = NF_INET_LOCAL_IN, - .priority = NF_IP_PRI_CONNTRACK_CONFIRM, - }, -}; - -/* Fast function for those who don't want to parse /proc (and I don't - blame them). */ -/* Reversing the socket's dst/src point of view gives us the reply - mapping. */ -static int -getorigdst(struct sock *sk, int optval, void __user *user, int *len) -{ - const struct inet_sock *inet = inet_sk(sk); - const struct nf_conntrack_tuple_hash *h; - struct nf_conntrack_tuple tuple; - - memset(&tuple, 0, sizeof(tuple)); - - lock_sock(sk); - tuple.src.u3.ip = inet->inet_rcv_saddr; - tuple.src.u.tcp.port = inet->inet_sport; - tuple.dst.u3.ip = inet->inet_daddr; - tuple.dst.u.tcp.port = inet->inet_dport; - tuple.src.l3num = PF_INET; - tuple.dst.protonum = sk->sk_protocol; - release_sock(sk); - - /* We only do TCP and SCTP at the moment: is there a better way? */ - if (tuple.dst.protonum != IPPROTO_TCP && - tuple.dst.protonum != IPPROTO_SCTP) { - pr_debug("SO_ORIGINAL_DST: Not a TCP/SCTP socket\n"); - return -ENOPROTOOPT; - } - - if ((unsigned int) *len < sizeof(struct sockaddr_in)) { - pr_debug("SO_ORIGINAL_DST: len %d not %zu\n", - *len, sizeof(struct sockaddr_in)); - return -EINVAL; - } - - h = nf_conntrack_find_get(sock_net(sk), &nf_ct_zone_dflt, &tuple); - if (h) { - struct sockaddr_in sin; - struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h); - - sin.sin_family = AF_INET; - sin.sin_port = ct->tuplehash[IP_CT_DIR_ORIGINAL] - .tuple.dst.u.tcp.port; - sin.sin_addr.s_addr = ct->tuplehash[IP_CT_DIR_ORIGINAL] - .tuple.dst.u3.ip; - memset(sin.sin_zero, 0, sizeof(sin.sin_zero)); - - pr_debug("SO_ORIGINAL_DST: %pI4 %u\n", - &sin.sin_addr.s_addr, ntohs(sin.sin_port)); - nf_ct_put(ct); - if (copy_to_user(user, &sin, sizeof(sin)) != 0) - return -EFAULT; - else - return 0; - } - pr_debug("SO_ORIGINAL_DST: Can't find %pI4/%u-%pI4/%u.\n", - &tuple.src.u3.ip, ntohs(tuple.src.u.tcp.port), - &tuple.dst.u3.ip, ntohs(tuple.dst.u.tcp.port)); - return -ENOENT; -} - -#if IS_ENABLED(CONFIG_NF_CT_NETLINK) - -#include <linux/netfilter/nfnetlink.h> -#include <linux/netfilter/nfnetlink_conntrack.h> - -static int ipv4_tuple_to_nlattr(struct sk_buff *skb, - const struct nf_conntrack_tuple *tuple) -{ - if (nla_put_in_addr(skb, CTA_IP_V4_SRC, tuple->src.u3.ip) || - nla_put_in_addr(skb, CTA_IP_V4_DST, tuple->dst.u3.ip)) - goto nla_put_failure; - return 0; - -nla_put_failure: - return -1; -} - -static const struct nla_policy ipv4_nla_policy[CTA_IP_MAX+1] = { - [CTA_IP_V4_SRC] = { .type = NLA_U32 }, - [CTA_IP_V4_DST] = { .type = NLA_U32 }, -}; - -static int ipv4_nlattr_to_tuple(struct nlattr *tb[], - struct nf_conntrack_tuple *t) -{ - if (!tb[CTA_IP_V4_SRC] || !tb[CTA_IP_V4_DST]) - return -EINVAL; - - t->src.u3.ip = nla_get_in_addr(tb[CTA_IP_V4_SRC]); - t->dst.u3.ip = nla_get_in_addr(tb[CTA_IP_V4_DST]); - - return 0; -} -#endif - -static struct nf_sockopt_ops so_getorigdst = { - .pf = PF_INET, - .get_optmin = SO_ORIGINAL_DST, - .get_optmax = SO_ORIGINAL_DST+1, - .get = getorigdst, - .owner = THIS_MODULE, -}; - -static int ipv4_hooks_register(struct net *net) -{ - struct conntrack4_net *cnet = net_generic(net, conntrack4_net_id); - int err = 0; - - mutex_lock(®ister_ipv4_hooks); - - cnet->users++; - if (cnet->users > 1) - goto out_unlock; - - err = nf_defrag_ipv4_enable(net); - if (err) { - cnet->users = 0; - goto out_unlock; - } - - err = nf_register_net_hooks(net, ipv4_conntrack_ops, - ARRAY_SIZE(ipv4_conntrack_ops)); - - if (err) - cnet->users = 0; - out_unlock: - mutex_unlock(®ister_ipv4_hooks); - return err; -} - -static void ipv4_hooks_unregister(struct net *net) -{ - struct conntrack4_net *cnet = net_generic(net, conntrack4_net_id); - - mutex_lock(®ister_ipv4_hooks); - if (cnet->users && (--cnet->users == 0)) - nf_unregister_net_hooks(net, ipv4_conntrack_ops, - ARRAY_SIZE(ipv4_conntrack_ops)); - mutex_unlock(®ister_ipv4_hooks); -} - -const struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv4 = { - .l3proto = PF_INET, - .pkt_to_tuple = ipv4_pkt_to_tuple, - .invert_tuple = ipv4_invert_tuple, - .get_l4proto = ipv4_get_l4proto, -#if IS_ENABLED(CONFIG_NF_CT_NETLINK) - .tuple_to_nlattr = ipv4_tuple_to_nlattr, - .nlattr_to_tuple = ipv4_nlattr_to_tuple, - .nla_policy = ipv4_nla_policy, - .nla_size = NLA_ALIGN(NLA_HDRLEN + sizeof(u32)) + /* CTA_IP_V4_SRC */ - NLA_ALIGN(NLA_HDRLEN + sizeof(u32)), /* CTA_IP_V4_DST */ -#endif - .net_ns_get = ipv4_hooks_register, - .net_ns_put = ipv4_hooks_unregister, - .me = THIS_MODULE, -}; - -module_param_call(hashsize, nf_conntrack_set_hashsize, param_get_uint, - &nf_conntrack_htable_size, 0600); - -MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET)); -MODULE_ALIAS("ip_conntrack"); -MODULE_LICENSE("GPL"); - -static const struct nf_conntrack_l4proto * const builtin_l4proto4[] = { - &nf_conntrack_l4proto_tcp4, - &nf_conntrack_l4proto_udp4, - &nf_conntrack_l4proto_icmp, -#ifdef CONFIG_NF_CT_PROTO_DCCP - &nf_conntrack_l4proto_dccp4, -#endif -#ifdef CONFIG_NF_CT_PROTO_SCTP - &nf_conntrack_l4proto_sctp4, -#endif -#ifdef CONFIG_NF_CT_PROTO_UDPLITE - &nf_conntrack_l4proto_udplite4, -#endif -}; - -static int ipv4_net_init(struct net *net) -{ - return nf_ct_l4proto_pernet_register(net, builtin_l4proto4, - ARRAY_SIZE(builtin_l4proto4)); -} - -static void ipv4_net_exit(struct net *net) -{ - nf_ct_l4proto_pernet_unregister(net, builtin_l4proto4, - ARRAY_SIZE(builtin_l4proto4)); -} - -static struct pernet_operations ipv4_net_ops = { - .init = ipv4_net_init, - .exit = ipv4_net_exit, - .id = &conntrack4_net_id, - .size = sizeof(struct conntrack4_net), -}; - -static int __init nf_conntrack_l3proto_ipv4_init(void) -{ - int ret = 0; - - need_conntrack(); - -#if IS_ENABLED(CONFIG_NF_CT_NETLINK) - if (WARN_ON(nla_policy_len(ipv4_nla_policy, CTA_IP_MAX + 1) != - nf_conntrack_l3proto_ipv4.nla_size)) - return -EINVAL; -#endif - ret = nf_register_sockopt(&so_getorigdst); - if (ret < 0) { - pr_err("Unable to register netfilter socket option\n"); - return ret; - } - - ret = register_pernet_subsys(&ipv4_net_ops); - if (ret < 0) { - pr_err("nf_conntrack_ipv4: can't register pernet ops\n"); - goto cleanup_sockopt; - } - - ret = nf_ct_l4proto_register(builtin_l4proto4, - ARRAY_SIZE(builtin_l4proto4)); - if (ret < 0) - goto cleanup_pernet; - - ret = nf_ct_l3proto_register(&nf_conntrack_l3proto_ipv4); - if (ret < 0) { - pr_err("nf_conntrack_ipv4: can't register ipv4 proto.\n"); - goto cleanup_l4proto; - } - - return ret; -cleanup_l4proto: - nf_ct_l4proto_unregister(builtin_l4proto4, - ARRAY_SIZE(builtin_l4proto4)); - cleanup_pernet: - unregister_pernet_subsys(&ipv4_net_ops); - cleanup_sockopt: - nf_unregister_sockopt(&so_getorigdst); - return ret; -} - -static void __exit nf_conntrack_l3proto_ipv4_fini(void) -{ - synchronize_net(); - nf_ct_l3proto_unregister(&nf_conntrack_l3proto_ipv4); - nf_ct_l4proto_unregister(builtin_l4proto4, - ARRAY_SIZE(builtin_l4proto4)); - unregister_pernet_subsys(&ipv4_net_ops); - nf_unregister_sockopt(&so_getorigdst); -} - -module_init(nf_conntrack_l3proto_ipv4_init); -module_exit(nf_conntrack_l3proto_ipv4_fini); |