datapath: Accept any 802.2 eth_type mask but override to be exact match

When key.eth_type is absent it is interpreted to be 802.2, which is
represented by a special value. In order to prevent inadvertant matches
on this opaque value, the mask is forced to be either fully wildcarded
or fully exact.

Signed-off-by: Andy Zhou <azhou@nicira.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>

diff --git a/datapath/flow.c b/datapath/flow.c
index 4d18aad..0a6e040 100644 (file)
--- a/datapath/flow.c
+++ b/datapath/flow.c
@@ -137,11 +137,8 @@ static bool ovs_match_validate(const struct sw_flow_match *match,
 
        /* Always allowed mask fields. */
        mask_allowed |= ((1ULL << OVS_KEY_ATTR_TUNNEL)
-                      | (1ULL << OVS_KEY_ATTR_IN_PORT));
-
-       if (match->key->eth.type == htons(ETH_P_802_2) &&
-           match->mask && (match->mask->key.eth.type == htons(0xffff)))
-               mask_allowed |= (1ULL << OVS_KEY_ATTR_ETHERTYPE);
+                      | (1ULL << OVS_KEY_ATTR_IN_PORT)
+                      | (11ULL << OVS_KEY_ATTR_ETHERTYPE));
 
        /* Check key attributes. */
        if (match->key->eth.type == htons(ETH_P_ARP)
@@ -1386,7 +1383,10 @@ static int ovs_key_from_nlattrs(struct sw_flow_match *match,  u64 attrs,
                __be16 eth_type;
 
                eth_type = nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]);
-               if (!is_mask && ntohs(eth_type) < ETH_P_802_3_MIN) {
+               if (is_mask) {
+                       /* Always exact match EtherType. */
+                       eth_type = htons(0xffff);
+               } else if (ntohs(eth_type) < ETH_P_802_3_MIN) {
                        OVS_NLERR("EtherType is less than mimimum (type=%x, min=%x).\n",
                                        ntohs(eth_type), ETH_P_802_3_MIN);
                        return -EINVAL;