--- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -310,6 +310,33 @@ struct ipt_entry *ipt_next_entry(const s return (void *)entry + entry->next_offset; } +static bool +ipt_handle_default_rule(struct ipt_entry *e, unsigned int *verdict) +{ + struct xt_entry_target *t; + struct xt_standard_target *st; + + if (e->target_offset != sizeof(struct ipt_entry)) + return false; + + if (!(e->ip.flags & IPT_F_NO_DEF_MATCH)) + return false; + + t = ipt_get_target(e); + if (t->u.kernel.target->target) + return false; + + st = (struct xt_standard_target *) t; + if (st->verdict == XT_RETURN) + return false; + + if (st->verdict >= 0) + return false; + + *verdict = (unsigned)(-st->verdict) - 1; + return true; +} + /* Returns one of the generic firewall policies, like NF_ACCEPT. */ unsigned int ipt_do_table(struct sk_buff *skb, @@ -331,9 +358,27 @@ ipt_do_table(struct sk_buff *skb, unsigned int addend; /* Initialization */ + IP_NF_ASSERT(table->valid_hooks & (1 << hook)); + local_bh_disable(); + private = table->private; + cpu = smp_processor_id(); + table_base = private->entries[cpu]; + e = get_entry(table_base, private->hook_entry[hook]); + if (ipt_handle_default_rule(e, &verdict)) { + ADD_COUNTER(e->counters, skb->len, 1); + local_bh_enable(); + return verdict; + } + ip = ip_hdr(skb); indev = in ? in->name : nulldevname; outdev = out ? out->name : nulldevname; + + addend = xt_write_recseq_begin(); + jumpstack = (struct ipt_entry **)private->jumpstack[cpu]; + stackptr = per_cpu_ptr(private->stackptr, cpu); + origptr = *stackptr; + /* We handle fragments by dealing with the first fragment as * if it was a normal packet. All other fragments are treated * normally, except that they will NEVER match rules that ask @@ -348,18 +393,6 @@ ipt_do_table(struct sk_buff *skb, acpar.family = NFPROTO_IPV4; acpar.hooknum = hook; - IP_NF_ASSERT(table->valid_hooks & (1 << hook)); - local_bh_disable(); - addend = xt_write_recseq_begin(); - private = table->private; - cpu = smp_processor_id(); - table_base = private->entries[cpu]; - jumpstack = (struct ipt_entry **)private->jumpstack[cpu]; - stackptr = per_cpu_ptr(private->stackptr, cpu); - origptr = *stackptr; - - e = get_entry(table_base, private->hook_entry[hook]); - pr_debug("Entering %s(hook %u); sp at %u (UF %p)\n", table->name, hook, origptr, get_entry(table_base, private->underflow[hook]));