[PATCH AUTOSEL 4.19 01/97] netfilter: ipset: Allow matching on destination MAC address for mac and ipmac sets

[Sasha Levin]

From: Stefano Brivio <sbri...@redhat.com>

[ Upstream commit 8cc4ccf58379935f3ad456cc34e61c4e4c921d0e ]

There doesn't seem to be any reason to restrict MAC address
matching to source MAC addresses in set types bitmap:ipmac,
hash:ipmac and hash:mac. With this patch, and this setup:

  ip netns add A
  ip link add veth1 type veth peer name veth2 netns A
  ip addr add 192.0.2.1/24 dev veth1
  ip -net A addr add 192.0.2.2/24 dev veth2
  ip link set veth1 up
  ip -net A link set veth2 up

  ip netns exec A ipset create test hash:mac
  dst=$(ip netns exec A cat /sys/class/net/veth2/address)
  ip netns exec A ipset add test ${dst}
  ip netns exec A iptables -P INPUT DROP
  ip netns exec A iptables -I INPUT -m set --match-set test dst -j ACCEPT

ipset will match packets based on destination MAC address:

  # ping -c1 192.0.2.2 >/dev/null
  # echo $?
  0

Reported-by: Yi Chen <yi...@redhat.com>
Signed-off-by: Stefano Brivio <sbri...@redhat.com>
Signed-off-by: Jozsef Kadlecsik <kad...@blackhole.kfki.hu>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 net/netfilter/ipset/ip_set_bitmap_ipmac.c | 10 +++++-----
 net/netfilter/ipset/ip_set_hash_ipmac.c   | 16 ++++++++++------
 net/netfilter/ipset/ip_set_hash_mac.c     | 10 +++++-----
 3 files changed, 20 insertions(+), 16 deletions(-)

diff --git a/net/netfilter/ipset/ip_set_bitmap_ipmac.c 
b/net/netfilter/ipset/ip_set_bitmap_ipmac.c
index c00b6a2e8e3c..13ade5782847 100644
--- a/net/netfilter/ipset/ip_set_bitmap_ipmac.c
+++ b/net/netfilter/ipset/ip_set_bitmap_ipmac.c
@@ -219,10 +219,6 @@ bitmap_ipmac_kadt(struct ip_set *set, const struct sk_buff 
*skb,
        struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
        u32 ip;
 
-       /* MAC can be src only */
-       if (!(opt->flags & IPSET_DIM_TWO_SRC))
-               return 0;
-
        ip = ntohl(ip4addr(skb, opt->flags & IPSET_DIM_ONE_SRC));
        if (ip < map->first_ip || ip > map->last_ip)
                return -IPSET_ERR_BITMAP_RANGE;
@@ -233,7 +229,11 @@ bitmap_ipmac_kadt(struct ip_set *set, const struct sk_buff 
*skb,
                return -EINVAL;
 
        e.id = ip_to_id(map, ip);
-       memcpy(e.ether, eth_hdr(skb)->h_source, ETH_ALEN);
+
+       if (opt->flags & IPSET_DIM_ONE_SRC)
+               ether_addr_copy(e.ether, eth_hdr(skb)->h_source);
+       else
+               ether_addr_copy(e.ether, eth_hdr(skb)->h_dest);
 
        return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
 }
diff --git a/net/netfilter/ipset/ip_set_hash_ipmac.c 
b/net/netfilter/ipset/ip_set_hash_ipmac.c
index 1ab5ed2f6839..fd87de3ed55b 100644
--- a/net/netfilter/ipset/ip_set_hash_ipmac.c
+++ b/net/netfilter/ipset/ip_set_hash_ipmac.c
@@ -103,7 +103,11 @@ hash_ipmac4_kadt(struct ip_set *set, const struct sk_buff 
*skb,
            (skb_mac_header(skb) + ETH_HLEN) > skb->data)
                return -EINVAL;
 
-       memcpy(e.ether, eth_hdr(skb)->h_source, ETH_ALEN);
+       if (opt->flags & IPSET_DIM_ONE_SRC)
+               ether_addr_copy(e.ether, eth_hdr(skb)->h_source);
+       else
+               ether_addr_copy(e.ether, eth_hdr(skb)->h_dest);
+
        if (ether_addr_equal(e.ether, invalid_ether))
                return -EINVAL;
 
@@ -211,15 +215,15 @@ hash_ipmac6_kadt(struct ip_set *set, const struct sk_buff 
*skb,
        };
        struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
 
-        /* MAC can be src only */
-       if (!(opt->flags & IPSET_DIM_TWO_SRC))
-               return 0;
-
        if (skb_mac_header(skb) < skb->head ||
            (skb_mac_header(skb) + ETH_HLEN) > skb->data)
                return -EINVAL;
 
-       memcpy(e.ether, eth_hdr(skb)->h_source, ETH_ALEN);
+       if (opt->flags & IPSET_DIM_ONE_SRC)
+               ether_addr_copy(e.ether, eth_hdr(skb)->h_source);
+       else
+               ether_addr_copy(e.ether, eth_hdr(skb)->h_dest);
+
        if (ether_addr_equal(e.ether, invalid_ether))
                return -EINVAL;
 
diff --git a/net/netfilter/ipset/ip_set_hash_mac.c 
b/net/netfilter/ipset/ip_set_hash_mac.c
index f9d5a2a1e3d0..4fe5f243d0a3 100644
--- a/net/netfilter/ipset/ip_set_hash_mac.c
+++ b/net/netfilter/ipset/ip_set_hash_mac.c
@@ -81,15 +81,15 @@ hash_mac4_kadt(struct ip_set *set, const struct sk_buff 
*skb,
        struct hash_mac4_elem e = { { .foo[0] = 0, .foo[1] = 0 } };
        struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
 
-        /* MAC can be src only */
-       if (!(opt->flags & IPSET_DIM_ONE_SRC))
-               return 0;
-
        if (skb_mac_header(skb) < skb->head ||
            (skb_mac_header(skb) + ETH_HLEN) > skb->data)
                return -EINVAL;
 
-       ether_addr_copy(e.ether, eth_hdr(skb)->h_source);
+       if (opt->flags & IPSET_DIM_ONE_SRC)
+               ether_addr_copy(e.ether, eth_hdr(skb)->h_source);
+       else
+               ether_addr_copy(e.ether, eth_hdr(skb)->h_dest);
+
        if (is_zero_ether_addr(e.ether))
                return -EINVAL;
        return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
-- 
2.19.1