From e2a3123fbe58da9fd3f35cd242087896ace6049f Mon Sep 17 00:00:00 2001 From: Yasuyuki Kozakai Date: Sat, 14 Jul 2007 20:45:14 -0700 Subject: [PATCH] [NETFILTER]: nf_conntrack: Introduces nf_ct_get_tuplepr and uses it nf_ct_get_tuple() requires the offset to transport header and that bothers callers such as icmp[v6] l4proto modules. This introduces new function to simplify them. Signed-off-by: Yasuyuki Kozakai Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- include/net/netfilter/nf_conntrack.h | 4 ++ net/ipv4/netfilter/nf_conntrack_proto_icmp.c | 32 ++++---------- .../netfilter/nf_conntrack_proto_icmpv6.c | 42 ++++--------------- net/netfilter/nf_conntrack_core.c | 30 +++++++++++++ 4 files changed, 49 insertions(+), 59 deletions(-) diff --git a/include/net/netfilter/nf_conntrack.h b/include/net/netfilter/nf_conntrack.h index d4f02eb0c6..810020ec34 100644 --- a/include/net/netfilter/nf_conntrack.h +++ b/include/net/netfilter/nf_conntrack.h @@ -186,6 +186,10 @@ extern void nf_conntrack_hash_insert(struct nf_conn *ct); extern void nf_conntrack_flush(void); +extern int nf_ct_get_tuplepr(const struct sk_buff *skb, + unsigned int nhoff, + u_int16_t l3num, + struct nf_conntrack_tuple *tuple); extern int nf_ct_invert_tuplepr(struct nf_conntrack_tuple *inverse, const struct nf_conntrack_tuple *orig); diff --git a/net/ipv4/netfilter/nf_conntrack_proto_icmp.c b/net/ipv4/netfilter/nf_conntrack_proto_icmp.c index 0fe8fb0466..b8b7999279 100644 --- a/net/ipv4/netfilter/nf_conntrack_proto_icmp.c +++ b/net/ipv4/netfilter/nf_conntrack_proto_icmp.c @@ -136,40 +136,22 @@ icmp_error_message(struct sk_buff *skb, 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; NF_CT_ASSERT(skb->nfct == NULL); - /* Not enough header? */ - inside = skb_header_pointer(skb, ip_hdrlen(skb), 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)) { - pr_debug("icmp_error_message: fragment of proto %u\n", - inside->ip.protocol); + /* Are they talking about one of our connections? */ + 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; } /* rcu_read_lock()ed by nf_hook_slow */ - innerproto = __nf_ct_l4proto_find(PF_INET, inside->ip.protocol); - - dataoff = ip_hdrlen(skb) + 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)) { - pr_debug("icmp_error_message: ! get_tuple p=%u", - inside->ip.protocol); - return -NF_ACCEPT; - } + 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. */ diff --git a/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c b/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c index 9defc7e145..0fca7e8abe 100644 --- a/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c +++ b/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c @@ -136,49 +136,23 @@ icmpv6_error_message(struct sk_buff *skb, { struct nf_conntrack_tuple intuple, origtuple; struct nf_conntrack_tuple_hash *h; - struct icmp6hdr _hdr, *hp; - unsigned int inip6off; struct nf_conntrack_l4proto *inproto; - u_int8_t inprotonum; - unsigned int inprotoff; NF_CT_ASSERT(skb->nfct == NULL); - hp = skb_header_pointer(skb, icmp6off, sizeof(_hdr), &_hdr); - if (hp == NULL) { - pr_debug("icmpv6_error: Can't get ICMPv6 hdr.\n"); - return -NF_ACCEPT; - } - - inip6off = icmp6off + sizeof(_hdr); - if (skb_copy_bits(skb, inip6off+offsetof(struct ipv6hdr, nexthdr), - &inprotonum, sizeof(inprotonum)) != 0) { - pr_debug("icmpv6_error: Can't get nexthdr in inner IPv6 " - "header.\n"); - return -NF_ACCEPT; - } - inprotoff = nf_ct_ipv6_skip_exthdr(skb, - inip6off + sizeof(struct ipv6hdr), - &inprotonum, - skb->len - inip6off - - sizeof(struct ipv6hdr)); - - if ((inprotoff > skb->len) || (inprotonum == NEXTHDR_FRAGMENT)) { - pr_debug("icmpv6_error: Can't get protocol header in ICMPv6 " - "payload.\n"); - return -NF_ACCEPT; - } - - /* rcu_read_lock()ed by nf_hook_slow */ - inproto = __nf_ct_l4proto_find(PF_INET6, inprotonum); - /* Are they talking about one of our connections? */ - if (!nf_ct_get_tuple(skb, inip6off, inprotoff, PF_INET6, inprotonum, - &origtuple, &nf_conntrack_l3proto_ipv6, inproto)) { + if (!nf_ct_get_tuplepr(skb, + skb_network_offset(skb) + + sizeof(struct ipv6hdr) + + sizeof(struct icmp6hdr), + PF_INET6, &origtuple)) { pr_debug("icmpv6_error: Can't get tuple\n"); return -NF_ACCEPT; } + /* rcu_read_lock()ed by nf_hook_slow */ + inproto = __nf_ct_l4proto_find(PF_INET6, origtuple.dst.protonum); + /* Ordinarily, we'd expect the inverted tupleproto, but it's been preserved inside the ICMP. */ if (!nf_ct_invert_tuple(&intuple, &origtuple, diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 5b194e3c4e..8cce814f6b 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -113,6 +113,36 @@ nf_ct_get_tuple(const struct sk_buff *skb, } EXPORT_SYMBOL_GPL(nf_ct_get_tuple); +int nf_ct_get_tuplepr(const struct sk_buff *skb, + unsigned int nhoff, + u_int16_t l3num, + struct nf_conntrack_tuple *tuple) +{ + struct nf_conntrack_l3proto *l3proto; + struct nf_conntrack_l4proto *l4proto; + unsigned int protoff; + u_int8_t protonum; + int ret; + + rcu_read_lock(); + + l3proto = __nf_ct_l3proto_find(l3num); + ret = l3proto->get_l4proto(skb, nhoff, &protoff, &protonum); + if (ret != NF_ACCEPT) { + rcu_read_unlock(); + return 0; + } + + l4proto = __nf_ct_l4proto_find(l3num, protonum); + + ret = nf_ct_get_tuple(skb, nhoff, protoff, l3num, protonum, tuple, + l3proto, l4proto); + + rcu_read_unlock(); + return ret; +} +EXPORT_SYMBOL_GPL(nf_ct_get_tuplepr); + int nf_ct_invert_tuple(struct nf_conntrack_tuple *inverse, const struct nf_conntrack_tuple *orig, -- 2.39.5