netfilter: net/ipv[46]/netfilter: Move && and || to end of previous line
[safe/jmp/linux-2.6] / net / ipv4 / netfilter / nf_conntrack_proto_icmp.c
index d25002f..e3dd936 100644 (file)
@@ -4,15 +4,9 @@
  * 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.
- *
- * 16 Dec 2003: Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
- *     - enable working with Layer 3 protocol independent connection tracking.
- *
- * Derived from net/ipv4/netfilter/ip_conntrack_proto_icmp.c
  */
 
 #include <linux/types.h>
-#include <linux/sched.h>
 #include <linux/timer.h>
 #include <linux/netfilter.h>
 #include <linux/in.h>
 #include <net/netfilter/nf_conntrack_tuple.h>
 #include <net/netfilter/nf_conntrack_l4proto.h>
 #include <net/netfilter/nf_conntrack_core.h>
+#include <net/netfilter/nf_log.h>
 
-static unsigned long nf_ct_icmp_timeout __read_mostly = 30*HZ;
-
-#if 0
-#define DEBUGP printk
-#else
-#define DEBUGP(format, args...)
-#endif
+static unsigned int nf_ct_icmp_timeout __read_mostly = 30*HZ;
 
-static int icmp_pkt_to_tuple(const struct sk_buff *skb,
-                            unsigned int dataoff,
-                            struct nf_conntrack_tuple *tuple)
+static bool icmp_pkt_to_tuple(const struct sk_buff *skb, unsigned int dataoff,
+                             struct nf_conntrack_tuple *tuple)
 {
-       struct icmphdr _hdr, *hp;
+       const struct icmphdr *hp;
+       struct icmphdr _hdr;
 
        hp = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
        if (hp == NULL)
-               return 0;
+               return false;
 
        tuple->dst.u.icmp.type = hp->type;
        tuple->src.u.icmp.id = hp->un.echo.id;
        tuple->dst.u.icmp.code = hp->code;
 
-       return 1;
+       return true;
 }
 
 /* Add 1; spaces filled with 0. */
@@ -62,17 +51,17 @@ static const u_int8_t invmap[] = {
        [ICMP_ADDRESSREPLY] = ICMP_ADDRESS + 1
 };
 
-static int icmp_invert_tuple(struct nf_conntrack_tuple *tuple,
-                            const struct nf_conntrack_tuple *orig)
+static bool icmp_invert_tuple(struct nf_conntrack_tuple *tuple,
+                             const struct nf_conntrack_tuple *orig)
 {
-       if (orig->dst.u.icmp.type >= sizeof(invmap)
-           || !invmap[orig->dst.u.icmp.type])
-               return 0;
+       if (orig->dst.u.icmp.type >= sizeof(invmap) ||
+           !invmap[orig->dst.u.icmp.type])
+               return false;
 
        tuple->src.u.icmp.id = orig->src.u.icmp.id;
        tuple->dst.u.icmp.type = invmap[orig->dst.u.icmp.type] - 1;
        tuple->dst.u.icmp.code = orig->dst.u.icmp.code;
-       return 1;
+       return true;
 }
 
 /* Print out the per-protocol part of the tuple. */
@@ -85,41 +74,25 @@ static int icmp_print_tuple(struct seq_file *s,
                          ntohs(tuple->src.u.icmp.id));
 }
 
-/* Print out the private part of the conntrack. */
-static int icmp_print_conntrack(struct seq_file *s,
-                               const struct nf_conn *conntrack)
-{
-       return 0;
-}
-
 /* Returns verdict for packet, or -1 for invalid. */
 static int icmp_packet(struct nf_conn *ct,
                       const struct sk_buff *skb,
                       unsigned int dataoff,
                       enum ip_conntrack_info ctinfo,
-                      int pf,
+                      u_int8_t pf,
                       unsigned int hooknum)
 {
-       /* Try to delete connection immediately after all replies:
-           won't actually vanish as we still have skb, and del_timer
-           means this will only run once even if count hits zero twice
-           (theoretically possible with SMP) */
-       if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY) {
-               if (atomic_dec_and_test(&ct->proto.icmp.count)
-                   && del_timer(&ct->timeout))
-                       ct->timeout.function((unsigned long)ct);
-       } else {
-               atomic_inc(&ct->proto.icmp.count);
-               nf_conntrack_event_cache(IPCT_PROTOINFO_VOLATILE, skb);
-               nf_ct_refresh_acct(ct, ctinfo, skb, nf_ct_icmp_timeout);
-       }
+       /* Do not immediately delete the connection after the first
+          successful reply to avoid excessive conntrackd traffic
+          and also to handle correctly ICMP echo reply duplicates. */
+       nf_ct_refresh_acct(ct, ctinfo, skb, nf_ct_icmp_timeout);
 
        return NF_ACCEPT;
 }
 
 /* Called when a new connection for this protocol found. */
-static int icmp_new(struct nf_conn *conntrack,
-                   const struct sk_buff *skb, unsigned int dataoff)
+static bool icmp_new(struct nf_conn *ct, const struct sk_buff *skb,
+                    unsigned int dataoff)
 {
        static const u_int8_t valid_new[] = {
                [ICMP_ECHO] = 1,
@@ -128,116 +101,87 @@ static int icmp_new(struct nf_conn *conntrack,
                [ICMP_ADDRESS] = 1
        };
 
-       if (conntrack->tuplehash[0].tuple.dst.u.icmp.type >= sizeof(valid_new)
-           || !valid_new[conntrack->tuplehash[0].tuple.dst.u.icmp.type]) {
+       if (ct->tuplehash[0].tuple.dst.u.icmp.type >= sizeof(valid_new) ||
+           !valid_new[ct->tuplehash[0].tuple.dst.u.icmp.type]) {
                /* Can't create a new ICMP `conn' with this. */
-               DEBUGP("icmp: can't create new conn with type %u\n",
-                      conntrack->tuplehash[0].tuple.dst.u.icmp.type);
-               NF_CT_DUMP_TUPLE(&conntrack->tuplehash[0].tuple);
-               return 0;
+               pr_debug("icmp: can't create new conn with type %u\n",
+                        ct->tuplehash[0].tuple.dst.u.icmp.type);
+               nf_ct_dump_tuple_ip(&ct->tuplehash[0].tuple);
+               return false;
        }
-       atomic_set(&conntrack->proto.icmp.count, 0);
-       return 1;
+       return true;
 }
 
-extern struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv4;
 /* Returns conntrack if it dealt with ICMP, and filled in skb fields */
 static int
-icmp_error_message(struct sk_buff *skb,
-                 enum ip_conntrack_info *ctinfo,
-                 unsigned int hooknum)
+icmp_error_message(struct net *net, struct sk_buff *skb,
+                enum ip_conntrack_info *ctinfo,
+                unsigned int hooknum)
 {
        struct nf_conntrack_tuple innertuple, origtuple;
-       struct {
-               struct icmphdr icmp;
-               struct iphdr ip;
-       } _in, *inside;
-       struct nf_conntrack_l4proto *innerproto;
-       struct nf_conntrack_tuple_hash *h;
-       int dataoff;
+       const struct nf_conntrack_l4proto *innerproto;
+       const struct nf_conntrack_tuple_hash *h;
 
        NF_CT_ASSERT(skb->nfct == NULL);
 
-       /* Not enough header? */
-       inside = skb_header_pointer(skb, skb->nh.iph->ihl*4, sizeof(_in), &_in);
-       if (inside == NULL)
-               return -NF_ACCEPT;
-
-       /* Ignore ICMP's containing fragments (shouldn't happen) */
-       if (inside->ip.frag_off & htons(IP_OFFSET)) {
-               DEBUGP("icmp_error_message: fragment of proto %u\n",
-                      inside->ip.protocol);
-               return -NF_ACCEPT;
-       }
-
-       innerproto = __nf_ct_l4proto_find(PF_INET, inside->ip.protocol);
-       dataoff = skb->nh.iph->ihl*4 + sizeof(inside->icmp);
        /* Are they talking about one of our connections? */
-       if (!nf_ct_get_tuple(skb, dataoff, dataoff + inside->ip.ihl*4, PF_INET,
-                            inside->ip.protocol, &origtuple,
-                            &nf_conntrack_l3proto_ipv4, innerproto)) {
-               DEBUGP("icmp_error_message: ! get_tuple p=%u",
-                      inside->ip.protocol);
+       if (!nf_ct_get_tuplepr(skb,
+                              skb_network_offset(skb) + ip_hdrlen(skb)
+                                                      + sizeof(struct icmphdr),
+                              PF_INET, &origtuple)) {
+               pr_debug("icmp_error_message: failed to get tuple\n");
                return -NF_ACCEPT;
        }
 
-        /* Ordinarily, we'd expect the inverted tupleproto, but it's
-           been preserved inside the ICMP. */
-        if (!nf_ct_invert_tuple(&innertuple, &origtuple,
+       /* rcu_read_lock()ed by nf_hook_slow */
+       innerproto = __nf_ct_l4proto_find(PF_INET, origtuple.dst.protonum);
+
+       /* Ordinarily, we'd expect the inverted tupleproto, but it's
+          been preserved inside the ICMP. */
+       if (!nf_ct_invert_tuple(&innertuple, &origtuple,
                                &nf_conntrack_l3proto_ipv4, innerproto)) {
-               DEBUGP("icmp_error_message: no match\n");
+               pr_debug("icmp_error_message: no match\n");
                return -NF_ACCEPT;
        }
 
        *ctinfo = IP_CT_RELATED;
 
-       h = nf_conntrack_find_get(&innertuple, NULL);
+       h = nf_conntrack_find_get(net, &innertuple);
        if (!h) {
-               /* Locally generated ICMPs will match inverted if they
-                  haven't been SNAT'ed yet */
-               /* FIXME: NAT code has to handle half-done double NAT --RR */
-               if (hooknum == NF_IP_LOCAL_OUT)
-                       h = nf_conntrack_find_get(&origtuple, NULL);
-
-               if (!h) {
-                       DEBUGP("icmp_error_message: no match\n");
-                       return -NF_ACCEPT;
-               }
-
-               /* Reverse direction from that found */
-               if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY)
-                       *ctinfo += IP_CT_IS_REPLY;
-       } else {
-               if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY)
-                       *ctinfo += IP_CT_IS_REPLY;
+               pr_debug("icmp_error_message: no match\n");
+               return -NF_ACCEPT;
        }
 
-        /* Update skb to refer to this connection */
-        skb->nfct = &nf_ct_tuplehash_to_ctrack(h)->ct_general;
-        skb->nfctinfo = *ctinfo;
-        return -NF_ACCEPT;
+       if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY)
+               *ctinfo += IP_CT_IS_REPLY;
+
+       /* Update skb to refer to this connection */
+       skb->nfct = &nf_ct_tuplehash_to_ctrack(h)->ct_general;
+       skb->nfctinfo = *ctinfo;
+       return -NF_ACCEPT;
 }
 
 /* Small and modified version of icmp_rcv */
 static int
-icmp_error(struct sk_buff *skb, unsigned int dataoff,
-          enum ip_conntrack_info *ctinfo, int pf, unsigned int hooknum)
+icmp_error(struct net *net, struct sk_buff *skb, unsigned int dataoff,
+          enum ip_conntrack_info *ctinfo, u_int8_t pf, unsigned int hooknum)
 {
-       struct icmphdr _ih, *icmph;
+       const struct icmphdr *icmph;
+       struct icmphdr _ih;
 
        /* Not enough header? */
-       icmph = skb_header_pointer(skb, skb->nh.iph->ihl*4, sizeof(_ih), &_ih);
+       icmph = skb_header_pointer(skb, ip_hdrlen(skb), sizeof(_ih), &_ih);
        if (icmph == NULL) {
-               if (LOG_INVALID(IPPROTO_ICMP))
+               if (LOG_INVALID(net, IPPROTO_ICMP))
                        nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
                                      "nf_ct_icmp: short packet ");
                return -NF_ACCEPT;
        }
 
        /* See ip_conntrack_proto_tcp.c */
-       if (nf_conntrack_checksum && hooknum == NF_IP_PRE_ROUTING &&
+       if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING &&
            nf_ip_checksum(skb, hooknum, dataoff, 0)) {
-               if (LOG_INVALID(IPPROTO_ICMP))
+               if (LOG_INVALID(net, IPPROTO_ICMP))
                        nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
                                      "nf_ct_icmp: bad HW ICMP checksum ");
                return -NF_ACCEPT;
@@ -250,110 +194,103 @@ icmp_error(struct sk_buff *skb, unsigned int dataoff,
         *                discarded.
         */
        if (icmph->type > NR_ICMP_TYPES) {
-               if (LOG_INVALID(IPPROTO_ICMP))
+               if (LOG_INVALID(net, IPPROTO_ICMP))
                        nf_log_packet(PF_INET, 0, skb, NULL, NULL, NULL,
                                      "nf_ct_icmp: invalid ICMP type ");
                return -NF_ACCEPT;
        }
 
        /* Need to track icmp error message? */
-       if (icmph->type != ICMP_DEST_UNREACH
-           && icmph->type != ICMP_SOURCE_QUENCH
-           && icmph->type != ICMP_TIME_EXCEEDED
-           && icmph->type != ICMP_PARAMETERPROB
-           && icmph->type != ICMP_REDIRECT)
+       if (icmph->type != ICMP_DEST_UNREACH &&
+           icmph->type != ICMP_SOURCE_QUENCH &&
+           icmph->type != ICMP_TIME_EXCEEDED &&
+           icmph->type != ICMP_PARAMETERPROB &&
+           icmph->type != ICMP_REDIRECT)
                return NF_ACCEPT;
 
-       return icmp_error_message(skb, ctinfo, hooknum);
+       return icmp_error_message(net, skb, ctinfo, hooknum);
 }
 
-#if defined(CONFIG_NF_CT_NETLINK) || \
-    defined(CONFIG_NF_CT_NETLINK_MODULE)
+#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
 
 #include <linux/netfilter/nfnetlink.h>
 #include <linux/netfilter/nfnetlink_conntrack.h>
 
-static int icmp_tuple_to_nfattr(struct sk_buff *skb,
+static int icmp_tuple_to_nlattr(struct sk_buff *skb,
                                const struct nf_conntrack_tuple *t)
 {
-       NFA_PUT(skb, CTA_PROTO_ICMP_ID, sizeof(u_int16_t),
-               &t->src.u.icmp.id);
-       NFA_PUT(skb, CTA_PROTO_ICMP_TYPE, sizeof(u_int8_t),
-               &t->dst.u.icmp.type);
-       NFA_PUT(skb, CTA_PROTO_ICMP_CODE, sizeof(u_int8_t),
-               &t->dst.u.icmp.code);
+       NLA_PUT_BE16(skb, CTA_PROTO_ICMP_ID, t->src.u.icmp.id);
+       NLA_PUT_U8(skb, CTA_PROTO_ICMP_TYPE, t->dst.u.icmp.type);
+       NLA_PUT_U8(skb, CTA_PROTO_ICMP_CODE, t->dst.u.icmp.code);
 
        return 0;
 
-nfattr_failure:
+nla_put_failure:
        return -1;
 }
 
-static const size_t cta_min_proto[CTA_PROTO_MAX] = {
-       [CTA_PROTO_ICMP_TYPE-1] = sizeof(u_int8_t),
-       [CTA_PROTO_ICMP_CODE-1] = sizeof(u_int8_t),
-       [CTA_PROTO_ICMP_ID-1]   = sizeof(u_int16_t)
+static const struct nla_policy icmp_nla_policy[CTA_PROTO_MAX+1] = {
+       [CTA_PROTO_ICMP_TYPE]   = { .type = NLA_U8 },
+       [CTA_PROTO_ICMP_CODE]   = { .type = NLA_U8 },
+       [CTA_PROTO_ICMP_ID]     = { .type = NLA_U16 },
 };
 
-static int icmp_nfattr_to_tuple(struct nfattr *tb[],
+static int icmp_nlattr_to_tuple(struct nlattr *tb[],
                                struct nf_conntrack_tuple *tuple)
 {
-       if (!tb[CTA_PROTO_ICMP_TYPE-1]
-           || !tb[CTA_PROTO_ICMP_CODE-1]
-           || !tb[CTA_PROTO_ICMP_ID-1])
-               return -EINVAL;
-
-       if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto))
+       if (!tb[CTA_PROTO_ICMP_TYPE] ||
+           !tb[CTA_PROTO_ICMP_CODE] ||
+           !tb[CTA_PROTO_ICMP_ID])
                return -EINVAL;
 
-       tuple->dst.u.icmp.type = 
-                       *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_ICMP_TYPE-1]);
-       tuple->dst.u.icmp.code =
-                       *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_ICMP_CODE-1]);
-       tuple->src.u.icmp.id =
-                       *(__be16 *)NFA_DATA(tb[CTA_PROTO_ICMP_ID-1]);
+       tuple->dst.u.icmp.type = nla_get_u8(tb[CTA_PROTO_ICMP_TYPE]);
+       tuple->dst.u.icmp.code = nla_get_u8(tb[CTA_PROTO_ICMP_CODE]);
+       tuple->src.u.icmp.id = nla_get_be16(tb[CTA_PROTO_ICMP_ID]);
 
-       if (tuple->dst.u.icmp.type >= sizeof(invmap)
-           || !invmap[tuple->dst.u.icmp.type])
+       if (tuple->dst.u.icmp.type >= sizeof(invmap) ||
+           !invmap[tuple->dst.u.icmp.type])
                return -EINVAL;
 
        return 0;
 }
+
+static int icmp_nlattr_tuple_size(void)
+{
+       return nla_policy_len(icmp_nla_policy, CTA_PROTO_MAX + 1);
+}
 #endif
 
 #ifdef CONFIG_SYSCTL
 static struct ctl_table_header *icmp_sysctl_header;
 static struct ctl_table icmp_sysctl_table[] = {
        {
-               .ctl_name       = NET_NF_CONNTRACK_ICMP_TIMEOUT,
                .procname       = "nf_conntrack_icmp_timeout",
                .data           = &nf_ct_icmp_timeout,
                .maxlen         = sizeof(unsigned int),
                .mode           = 0644,
-               .proc_handler   = &proc_dointvec_jiffies,
+               .proc_handler   = proc_dointvec_jiffies,
        },
-        {
+       {
                .ctl_name = 0
        }
 };
 #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
 static struct ctl_table icmp_compat_sysctl_table[] = {
        {
-               .ctl_name       = NET_IPV4_NF_CONNTRACK_ICMP_TIMEOUT,
                .procname       = "ip_conntrack_icmp_timeout",
                .data           = &nf_ct_icmp_timeout,
                .maxlen         = sizeof(unsigned int),
                .mode           = 0644,
-               .proc_handler   = &proc_dointvec_jiffies,
+               .proc_handler   = proc_dointvec_jiffies,
        },
-        {
+       {
                .ctl_name = 0
        }
 };
 #endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
 #endif /* CONFIG_SYSCTL */
 
-struct nf_conntrack_l4proto nf_conntrack_l4proto_icmp =
+struct nf_conntrack_l4proto nf_conntrack_l4proto_icmp __read_mostly =
 {
        .l3proto                = PF_INET,
        .l4proto                = IPPROTO_ICMP,
@@ -361,16 +298,16 @@ struct nf_conntrack_l4proto nf_conntrack_l4proto_icmp =
        .pkt_to_tuple           = icmp_pkt_to_tuple,
        .invert_tuple           = icmp_invert_tuple,
        .print_tuple            = icmp_print_tuple,
-       .print_conntrack        = icmp_print_conntrack,
        .packet                 = icmp_packet,
        .new                    = icmp_new,
        .error                  = icmp_error,
        .destroy                = NULL,
        .me                     = NULL,
-#if defined(CONFIG_NF_CT_NETLINK) || \
-    defined(CONFIG_NF_CT_NETLINK_MODULE)
-       .tuple_to_nfattr        = icmp_tuple_to_nfattr,
-       .nfattr_to_tuple        = icmp_nfattr_to_tuple,
+#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
+       .tuple_to_nlattr        = icmp_tuple_to_nlattr,
+       .nlattr_tuple_size      = icmp_nlattr_tuple_size,
+       .nlattr_to_tuple        = icmp_nlattr_to_tuple,
+       .nla_policy             = icmp_nla_policy,
 #endif
 #ifdef CONFIG_SYSCTL
        .ctl_table_header       = &icmp_sysctl_header,
@@ -380,5 +317,3 @@ struct nf_conntrack_l4proto nf_conntrack_l4proto_icmp =
 #endif
 #endif
 };
-
-EXPORT_SYMBOL(nf_conntrack_l4proto_icmp);