packets: New function eth_set_vlan_tci(), from dpif-netdev.

This will soon be used in the upcoming bond library.

3 files changed, 33 insertions, 32 deletions

diff --git a/lib/dpif-netdev.c b/lib/dpif-netdev.c
index 486ba4865..5efc8697b 100644
--- a/lib/dpif-netdev.c
+++ b/lib/dpif-netdev.c
@@ -1136,36 +1136,6 @@ dp_netdev_wait(void)
 }
 
 
-/* Modify the TCI field of 'packet'.  If a VLAN tag is present, its TCI field
- * is replaced by 'tci'.  If a VLAN tag is not present, one is added with the
- * TCI field set to 'tci'.
- */
-static void
-dp_netdev_set_dl_tci(struct ofpbuf *packet, uint16_t tci)
-{
-    struct vlan_eth_header *veh;
-    struct eth_header *eh;
-
-    eh = packet->l2;
-    if (packet->size >= sizeof(struct vlan_eth_header)
-        && eh->eth_type == htons(ETH_TYPE_VLAN)) {
-        veh = packet->l2;
-        veh->veth_tci = tci;
-    } else {
-        /* Insert new 802.1Q header. */
-        struct vlan_eth_header tmp;
-        memcpy(tmp.veth_dst, eh->eth_dst, ETH_ADDR_LEN);
-        memcpy(tmp.veth_src, eh->eth_src, ETH_ADDR_LEN);
-        tmp.veth_type = htons(ETH_TYPE_VLAN);
-        tmp.veth_tci = tci;
-        tmp.veth_next_type = eh->eth_type;
-
-        veh = ofpbuf_push_uninit(packet, VLAN_HEADER_LEN);
-        memcpy(veh, &tmp, sizeof tmp);
-        packet->l2 = (char*)packet->l2 - VLAN_HEADER_LEN;
-    }
-}
-
 static void
 dp_netdev_strip_vlan(struct ofpbuf *packet)
 {
@@ -1368,7 +1338,7 @@ dp_netdev_execute_actions(struct dp_netdev *dp,
             break;
 
         case ODP_ACTION_ATTR_SET_DL_TCI:
-            dp_netdev_set_dl_tci(packet, nl_attr_get_be16(a));
+            eth_set_vlan_tci(packet, nl_attr_get_be16(a));
             break;
 
         case ODP_ACTION_ATTR_STRIP_VLAN:
diff --git a/lib/packets.c b/lib/packets.c
index f16e74951..83c852c13 100644
--- a/lib/packets.c
+++ b/lib/packets.c
@@ -75,6 +75,36 @@ compose_benign_packet(struct ofpbuf *b, const char *tag, uint16_t snap_type,
     memcpy(payload + tag_size, eth_src, ETH_ADDR_LEN);
 }
 
+/* Modify the TCI field of 'packet', whose data must begin with an Ethernet
+ * header.  If a VLAN tag is present, its TCI field is replaced by 'tci'.  If a
+ * VLAN tag is not present, one is added with the TCI field set to 'tci'.
+ *
+ * Also sets 'packet->l2' to point to the new Ethernet header. */
+void
+eth_set_vlan_tci(struct ofpbuf *packet, ovs_be16 tci)
+{
+    struct eth_header *eh = packet->data;
+    struct vlan_eth_header *veh;
+
+    if (packet->size >= sizeof(struct vlan_eth_header)
+        && eh->eth_type == htons(ETH_TYPE_VLAN)) {
+        veh = packet->data;
+        veh->veth_tci = tci;
+    } else {
+        /* Insert new 802.1Q header. */
+        struct vlan_eth_header tmp;
+        memcpy(tmp.veth_dst, eh->eth_dst, ETH_ADDR_LEN);
+        memcpy(tmp.veth_src, eh->eth_src, ETH_ADDR_LEN);
+        tmp.veth_type = htons(ETH_TYPE_VLAN);
+        tmp.veth_tci = tci;
+        tmp.veth_next_type = eh->eth_type;
+
+        veh = ofpbuf_push_uninit(packet, VLAN_HEADER_LEN);
+        memcpy(veh, &tmp, sizeof tmp);
+    }
+    packet->l2 = packet->data;
+}
+
 /* Stores the string representation of the IPv6 address 'addr' into the
  * character array 'addr_str', which must be at least INET6_ADDRSTRLEN
  * bytes long. */
@@ -163,7 +193,6 @@ ipv6_count_cidr_bits(const struct in6_addr *netmask)
     return count;
 }
 
-
 /* Returns true if 'netmask' is a CIDR netmask, that is, if it consists of N
  * high-order 1-bits and 128-N low-order 0-bits. */
 bool
diff --git a/lib/packets.h b/lib/packets.h
index 42d225c23..251fc1cb3 100644
--- a/lib/packets.h
+++ b/lib/packets.h
@@ -131,6 +131,8 @@ void compose_benign_packet(struct ofpbuf *, const char *tag,
                            uint16_t snap_type,
                            const uint8_t eth_src[ETH_ADDR_LEN]);
 
+void eth_set_vlan_tci(struct ofpbuf *, ovs_be16 tci);
+
 /* Example:
  *
  * uint8_t mac[ETH_ADDR_LEN];