netfilter: nf_conntrack: log packets dropped by helpers
[safe/jmp/linux-2.6] / net / ipv4 / netfilter / nf_conntrack_l3proto_ipv4.c
index 41e7961..aa95bb8 100644 (file)
@@ -1,3 +1,4 @@
+
 /* (C) 1999-2001 Paul `Rusty' Russell
  * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
  *
 #include <net/netfilter/nf_conntrack_core.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>
 
 int (*nf_nat_seq_adjust_hook)(struct sk_buff *skb,
                              struct nf_conn *ct,
                              enum ip_conntrack_info ctinfo);
 EXPORT_SYMBOL_GPL(nf_nat_seq_adjust_hook);
 
-static int ipv4_pkt_to_tuple(const struct sk_buff *skb, unsigned int nhoff,
-                            struct nf_conntrack_tuple *tuple)
+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 0;
+               return false;
 
        tuple->src.u3.ip = ap[0];
        tuple->dst.u3.ip = ap[1];
 
-       return 1;
+       return true;
 }
 
-static int ipv4_invert_tuple(struct nf_conntrack_tuple *tuple,
-                          const struct nf_conntrack_tuple *orig)
+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 1;
+       return true;
 }
 
 static int ipv4_print_tuple(struct seq_file *s,
                            const struct nf_conntrack_tuple *tuple)
 {
-       return seq_printf(s, "src=%u.%u.%u.%u dst=%u.%u.%u.%u ",
-                         NIPQUAD(tuple->src.u3.ip),
-                         NIPQUAD(tuple->dst.u3.ip));
-}
-
-/* Returns new sk_buff, or NULL */
-static int nf_ct_ipv4_gather_frags(struct sk_buff *skb, u_int32_t user)
-{
-       int err;
-
-       skb_orphan(skb);
-
-       local_bh_disable();
-       err = ip_defrag(skb, user);
-       local_bh_enable();
-
-       if (!err)
-               ip_send_check(ip_hdr(skb));
-
-       return err;
+       return seq_printf(s, "src=%pI4 dst=%pI4 ",
+                         &tuple->src.u3.ip, &tuple->dst.u3.ip);
 }
 
 static int ipv4_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
@@ -129,50 +114,33 @@ static unsigned int ipv4_confirm(unsigned int hooknum,
 
        ret = helper->help(skb, skb_network_offset(skb) + ip_hdrlen(skb),
                           ct, ctinfo);
-       if (ret != NF_ACCEPT)
+       if (ret != NF_ACCEPT) {
+               nf_log_packet(NFPROTO_IPV4, hooknum, skb, in, out, NULL,
+                             "nf_ct_%s: dropping packet", helper->name);
                return ret;
+       }
 
        if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status)) {
                typeof(nf_nat_seq_adjust_hook) seq_adjust;
 
                seq_adjust = rcu_dereference(nf_nat_seq_adjust_hook);
-               if (!seq_adjust || !seq_adjust(skb, ct, ctinfo))
+               if (!seq_adjust || !seq_adjust(skb, ct, ctinfo)) {
+                       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_defrag(unsigned int hooknum,
-                                         struct sk_buff *skb,
-                                         const struct net_device *in,
-                                         const struct net_device *out,
-                                         int (*okfn)(struct sk_buff *))
-{
-       /* Previously seen (loopback)?  Ignore.  Do this before
-          fragment check. */
-       if (skb->nfct)
-               return NF_ACCEPT;
-
-       /* Gather fragments. */
-       if (ip_hdr(skb)->frag_off & htons(IP_MF | IP_OFFSET)) {
-               if (nf_ct_ipv4_gather_frags(skb,
-                                           hooknum == NF_INET_PRE_ROUTING ?
-                                           IP_DEFRAG_CONNTRACK_IN :
-                                           IP_DEFRAG_CONNTRACK_OUT))
-                       return NF_STOLEN;
-       }
-       return NF_ACCEPT;
-}
-
 static unsigned int ipv4_conntrack_in(unsigned int hooknum,
                                      struct sk_buff *skb,
                                      const struct net_device *in,
                                      const struct net_device *out,
                                      int (*okfn)(struct sk_buff *))
 {
-       return nf_conntrack_in(PF_INET, hooknum, skb);
+       return nf_conntrack_in(dev_net(in), PF_INET, hooknum, skb);
 }
 
 static unsigned int ipv4_conntrack_local(unsigned int hooknum,
@@ -183,56 +151,39 @@ static unsigned int ipv4_conntrack_local(unsigned int hooknum,
 {
        /* root is playing with raw sockets. */
        if (skb->len < sizeof(struct iphdr) ||
-           ip_hdrlen(skb) < sizeof(struct iphdr)) {
-               if (net_ratelimit())
-                       printk("ipt_hook: happy cracking.\n");
+           ip_hdrlen(skb) < sizeof(struct iphdr))
                return NF_ACCEPT;
-       }
-       return nf_conntrack_in(PF_INET, hooknum, skb);
+       return nf_conntrack_in(dev_net(out), PF_INET, hooknum, skb);
 }
 
 /* Connection tracking may drop packets, but never alters them, so
    make it the first hook. */
 static struct nf_hook_ops ipv4_conntrack_ops[] __read_mostly = {
        {
-               .hook           = ipv4_conntrack_defrag,
-               .owner          = THIS_MODULE,
-               .pf             = PF_INET,
-               .hooknum        = NF_INET_PRE_ROUTING,
-               .priority       = NF_IP_PRI_CONNTRACK_DEFRAG,
-       },
-       {
                .hook           = ipv4_conntrack_in,
                .owner          = THIS_MODULE,
-               .pf             = PF_INET,
+               .pf             = NFPROTO_IPV4,
                .hooknum        = NF_INET_PRE_ROUTING,
                .priority       = NF_IP_PRI_CONNTRACK,
        },
        {
-               .hook           = ipv4_conntrack_defrag,
-               .owner          = THIS_MODULE,
-               .pf             = PF_INET,
-               .hooknum        = NF_INET_LOCAL_OUT,
-               .priority       = NF_IP_PRI_CONNTRACK_DEFRAG,
-       },
-       {
                .hook           = ipv4_conntrack_local,
                .owner          = THIS_MODULE,
-               .pf             = PF_INET,
+               .pf             = NFPROTO_IPV4,
                .hooknum        = NF_INET_LOCAL_OUT,
                .priority       = NF_IP_PRI_CONNTRACK,
        },
        {
                .hook           = ipv4_confirm,
                .owner          = THIS_MODULE,
-               .pf             = PF_INET,
+               .pf             = NFPROTO_IPV4,
                .hooknum        = NF_INET_POST_ROUTING,
                .priority       = NF_IP_PRI_CONNTRACK_CONFIRM,
        },
        {
                .hook           = ipv4_confirm,
                .owner          = THIS_MODULE,
-               .pf             = PF_INET,
+               .pf             = NFPROTO_IPV4,
                .hooknum        = NF_INET_LOCAL_IN,
                .priority       = NF_IP_PRI_CONNTRACK_CONFIRM,
        },
@@ -249,15 +200,15 @@ static ctl_table ip_ct_sysctl_table[] = {
                .data           = &nf_conntrack_max,
                .maxlen         = sizeof(int),
                .mode           = 0644,
-               .proc_handler   = &proc_dointvec,
+               .proc_handler   = proc_dointvec,
        },
        {
                .ctl_name       = NET_IPV4_NF_CONNTRACK_COUNT,
                .procname       = "ip_conntrack_count",
-               .data           = &nf_conntrack_count,
+               .data           = &init_net.ct.count,
                .maxlen         = sizeof(int),
                .mode           = 0444,
-               .proc_handler   = &proc_dointvec,
+               .proc_handler   = proc_dointvec,
        },
        {
                .ctl_name       = NET_IPV4_NF_CONNTRACK_BUCKETS,
@@ -265,24 +216,24 @@ static ctl_table ip_ct_sysctl_table[] = {
                .data           = &nf_conntrack_htable_size,
                .maxlen         = sizeof(unsigned int),
                .mode           = 0444,
-               .proc_handler   = &proc_dointvec,
+               .proc_handler   = proc_dointvec,
        },
        {
                .ctl_name       = NET_IPV4_NF_CONNTRACK_CHECKSUM,
                .procname       = "ip_conntrack_checksum",
-               .data           = &nf_conntrack_checksum,
+               .data           = &init_net.ct.sysctl_checksum,
                .maxlen         = sizeof(int),
                .mode           = 0644,
-               .proc_handler   = &proc_dointvec,
+               .proc_handler   = proc_dointvec,
        },
        {
                .ctl_name       = NET_IPV4_NF_CONNTRACK_LOG_INVALID,
                .procname       = "ip_conntrack_log_invalid",
-               .data           = &nf_ct_log_invalid,
+               .data           = &init_net.ct.sysctl_log_invalid,
                .maxlen         = sizeof(unsigned int),
                .mode           = 0644,
-               .proc_handler   = &proc_dointvec_minmax,
-               .strategy       = &sysctl_intvec,
+               .proc_handler   = proc_dointvec_minmax,
+               .strategy       = sysctl_intvec,
                .extra1         = &log_invalid_proto_min,
                .extra2         = &log_invalid_proto_max,
        },
@@ -303,17 +254,17 @@ getorigdst(struct sock *sk, int optval, void __user *user, int *len)
        const struct nf_conntrack_tuple_hash *h;
        struct nf_conntrack_tuple tuple;
 
-       NF_CT_TUPLE_U_BLANK(&tuple);
+       memset(&tuple, 0, sizeof(tuple));
        tuple.src.u3.ip = inet->rcv_saddr;
        tuple.src.u.tcp.port = inet->sport;
        tuple.dst.u3.ip = inet->daddr;
        tuple.dst.u.tcp.port = inet->dport;
        tuple.src.l3num = PF_INET;
-       tuple.dst.protonum = IPPROTO_TCP;
+       tuple.dst.protonum = sk->sk_protocol;
 
-       /* We only do TCP at the moment: is there a better way? */
-       if (strcmp(sk->sk_prot->name, "TCP")) {
-               pr_debug("SO_ORIGINAL_DST: Not a TCP socket\n");
+       /* We only do TCP and SCTP at the moment: is there a better way? */
+       if (sk->sk_protocol != IPPROTO_TCP && sk->sk_protocol != IPPROTO_SCTP) {
+               pr_debug("SO_ORIGINAL_DST: Not a TCP/SCTP socket\n");
                return -ENOPROTOOPT;
        }
 
@@ -323,7 +274,7 @@ getorigdst(struct sock *sk, int optval, void __user *user, int *len)
                return -EINVAL;
        }
 
-       h = nf_conntrack_find_get(&tuple);
+       h = nf_conntrack_find_get(sock_net(sk), &tuple);
        if (h) {
                struct sockaddr_in sin;
                struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h);
@@ -335,17 +286,17 @@ getorigdst(struct sock *sk, int optval, void __user *user, int *len)
                        .tuple.dst.u3.ip;
                memset(sin.sin_zero, 0, sizeof(sin.sin_zero));
 
-               pr_debug("SO_ORIGINAL_DST: %u.%u.%u.%u %u\n",
-                        NIPQUAD(sin.sin_addr.s_addr), ntohs(sin.sin_port));
+               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 %u.%u.%u.%u/%u-%u.%u.%u.%u/%u.\n",
-                NIPQUAD(tuple.src.u3.ip), ntohs(tuple.src.u.tcp.port),
-                NIPQUAD(tuple.dst.u3.ip), ntohs(tuple.dst.u.tcp.port));
+       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;
 }
 
@@ -381,6 +332,11 @@ static int ipv4_nlattr_to_tuple(struct nlattr *tb[],
 
        return 0;
 }
+
+static int ipv4_nlattr_tuple_size(void)
+{
+       return nla_policy_len(ipv4_nla_policy, CTA_IP_MAX + 1);
+}
 #endif
 
 static struct nf_sockopt_ops so_getorigdst = {
@@ -400,6 +356,7 @@ struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv4 __read_mostly = {
        .get_l4proto     = ipv4_get_l4proto,
 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
        .tuple_to_nlattr = ipv4_tuple_to_nlattr,
+       .nlattr_tuple_size = ipv4_nlattr_tuple_size,
        .nlattr_to_tuple = ipv4_nlattr_to_tuple,
        .nla_policy      = ipv4_nla_policy,
 #endif
@@ -422,6 +379,7 @@ static int __init nf_conntrack_l3proto_ipv4_init(void)
        int ret = 0;
 
        need_conntrack();
+       nf_defrag_ipv4_enable();
 
        ret = nf_register_sockopt(&so_getorigdst);
        if (ret < 0) {