From 07a6cf771dc049600033453d700ea93b9449bd33 Mon Sep 17 00:00:00 2001
From: Ethan Jackson <ethan@nicira.com>
Date: Tue, 1 Mar 2011 13:27:23 -0800
Subject: [PATCH] packets: create new compose_lacp_pdu() function.

Creates new compose_lacp_pdu() from the old compose_lacp_packet()
function.  This will allow a LACP PDU to be created without
necessarily knowing the Ethernet Source Address required for
generating the packet.  Future patches rely on this functionality.
---
 lib/packets.c     | 21 ++++++++++++++-------
 lib/packets.h     |  8 +++++---
 vswitchd/bridge.c |  6 ++++--
 3 files changed, 23 insertions(+), 12 deletions(-)

diff --git a/lib/packets.c b/lib/packets.c
index 8791a3ce0..60ee3903d 100644
--- a/lib/packets.c
+++ b/lib/packets.c
@@ -204,25 +204,32 @@ ipv6_is_cidr(const struct in6_addr *netmask)
     return true;
 }
 
-/* Fills 'b' with a LACP packet whose source address is 'eth_src', LACP actor
- * information is 'actor', and LACP partner information is 'partner'. */
+/* Populates 'b' with a LACP packet containing 'pdu' with source address
+ * 'eth_src'. */
 void
-compose_lacp_packet(struct ofpbuf *b, struct lacp_info *actor,
-                    struct lacp_info *partner,
-                    const uint8_t eth_src[ETH_ADDR_LEN])
+compose_lacp_packet(struct ofpbuf *b, const uint8_t eth_src[ETH_ADDR_LEN],
+                    const struct lacp_pdu *pdu)
 {
     struct eth_header *eth;
-    struct lacp_pdu *pdu;
+    struct lacp_pdu *eth_pdu;
 
     ofpbuf_clear(b);
 
     ofpbuf_prealloc_tailroom(b, ETH_HEADER_LEN + LACP_PDU_LEN);
     eth = ofpbuf_put_zeros(b, ETH_HEADER_LEN);
-    pdu = ofpbuf_put_zeros(b, LACP_PDU_LEN);
+    eth_pdu = ofpbuf_put(b, pdu, LACP_PDU_LEN);
 
     memcpy(eth->eth_dst, eth_addr_lacp, ETH_ADDR_LEN);
     memcpy(eth->eth_src, eth_src, ETH_ADDR_LEN);
     eth->eth_type = htons(ETH_TYPE_LACP);
+}
+
+/* Populates 'pdu' with a LACP PDU comprised of 'actor' and 'partner'. */
+void
+compose_lacp_pdu(const struct lacp_info *actor,
+                 const struct lacp_info *partner, struct lacp_pdu *pdu)
+{
+    memset(pdu, 0, sizeof *pdu);
 
     pdu->subtype = 1;
     pdu->version = 1;
diff --git a/lib/packets.h b/lib/packets.h
index 0bc368b93..dcb5b9fe8 100644
--- a/lib/packets.h
+++ b/lib/packets.h
@@ -460,9 +460,11 @@ struct lacp_pdu {
 } __attribute__((packed));
 BUILD_ASSERT_DECL(LACP_PDU_LEN == sizeof(struct lacp_pdu));
 
-void compose_lacp_packet(struct ofpbuf *, struct lacp_info *actor,
-                         struct lacp_info *partner,
-                         const uint8_t eth_src[ETH_ADDR_LEN]);
+void compose_lacp_packet(struct ofpbuf *, const uint8_t eth_src[ETH_ADDR_LEN],
+                         const struct lacp_pdu *);
+
+void compose_lacp_pdu(const struct lacp_info *actor,
+                      const struct lacp_info *partner, struct lacp_pdu *);
 
 const struct lacp_pdu *parse_lacp_packet(const struct ofpbuf *);
 
diff --git a/vswitchd/bridge.c b/vswitchd/bridge.c
index 0cdc33b68..974cfaecd 100644
--- a/vswitchd/bridge.c
+++ b/vswitchd/bridge.c
@@ -3265,9 +3265,11 @@ lacp_run(struct port *port)
 
         error = netdev_get_etheraddr(iface->netdev, ea);
         if (!error) {
+            struct lacp_pdu pdu;
+
             iface->lacp_actor.state = iface_get_lacp_state(iface);
-            compose_lacp_packet(&packet, &iface->lacp_actor,
-                                &iface->lacp_partner, ea);
+            compose_lacp_pdu(&iface->lacp_actor, &iface->lacp_partner, &pdu);
+            compose_lacp_packet(&packet, ea, &pdu);
             iface_send_packet(iface, &packet);
         } else {
             static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 10);
-- 
2.39.5