[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 <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Yasuyuki Kozakai 2007-07-14 20:45:14 -07:00 committed by David S. Miller
parent ffc3069048
commit e2a3123fbe
4 changed files with 49 additions and 59 deletions

View file

@ -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);

View file

@ -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. */

View file

@ -136,48 +136,22 @@ 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");
/* Are they talking about one of our connections? */
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, 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)) {
pr_debug("icmpv6_error: Can't get tuple\n");
return -NF_ACCEPT;
}
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. */

View file

@ -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,