You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
openwrt/target/linux/generic/patches-4.9/610-netfilter_match_bypass_...

85 lines
2.2 KiB
Diff

--- a/include/uapi/linux/netfilter_ipv4/ip_tables.h
+++ b/include/uapi/linux/netfilter_ipv4/ip_tables.h
@@ -88,6 +88,7 @@ struct ipt_ip {
#define IPT_F_FRAG 0x01 /* Set if rule is a fragment rule */
#define IPT_F_GOTO 0x02 /* Set if jump is a goto */
#define IPT_F_MASK 0x03 /* All possible flag bits mask. */
+#define IPT_F_NO_DEF_MATCH 0x80 /* Internal: no default match rules present */
/* Values for "inv" field in struct ipt_ip. */
#define IPT_INV_VIA_IN 0x01 /* Invert the sense of IN IFACE. */
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -58,6 +58,9 @@ ip_packet_match(const struct iphdr *ip,
{
unsigned long ret;
+ if (ipinfo->flags & IPT_F_NO_DEF_MATCH)
+ return true;
+
if (NF_INVF(ipinfo, IPT_INV_SRCIP,
(ip->saddr & ipinfo->smsk.s_addr) != ipinfo->src.s_addr) ||
NF_INVF(ipinfo, IPT_INV_DSTIP,
@@ -88,6 +91,29 @@ ip_packet_match(const struct iphdr *ip,
return true;
}
+static void
+ip_checkdefault(struct ipt_ip *ip)
+{
+ static const char iface_mask[IFNAMSIZ] = {};
+
+ if (ip->invflags || ip->flags & IPT_F_FRAG)
+ return;
+
+ if (memcmp(ip->iniface_mask, iface_mask, IFNAMSIZ) != 0)
+ return;
+
+ if (memcmp(ip->outiface_mask, iface_mask, IFNAMSIZ) != 0)
+ return;
+
+ if (ip->smsk.s_addr || ip->dmsk.s_addr)
+ return;
+
+ if (ip->proto)
+ return;
+
+ ip->flags |= IPT_F_NO_DEF_MATCH;
+}
+
static bool
ip_checkentry(const struct ipt_ip *ip)
{
@@ -545,6 +571,8 @@ find_check_entry(struct ipt_entry *e, st
struct xt_entry_match *ematch;
unsigned long pcnt;
+ ip_checkdefault(&e->ip);
+
pcnt = xt_percpu_counter_alloc();
if (IS_ERR_VALUE(pcnt))
return -ENOMEM;
@@ -824,6 +852,7 @@ copy_entries_to_user(unsigned int total_
const struct xt_table_info *private = table->private;
int ret = 0;
const void *loc_cpu_entry;
+ u8 flags;
counters = alloc_counters(table);
if (IS_ERR(counters))
@@ -850,6 +879,14 @@ copy_entries_to_user(unsigned int total_
ret = -EFAULT;
goto free_counters;
}
+
+ flags = e->ip.flags & IPT_F_MASK;
+ if (copy_to_user(userptr + off
+ + offsetof(struct ipt_entry, ip.flags),
+ &flags, sizeof(flags)) != 0) {
+ ret = -EFAULT;
+ goto free_counters;
+ }
for (i = sizeof(struct ipt_entry);
i < e->target_offset;