[BRIDGE]: use LLC to send STP

The bridge code can use existing LLC output code when building
spanning tree protocol packets.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 59 insertions, 69 deletions

diff --git a/net/bridge/br_stp_bpdu.c b/net/bridge/br_stp_bpdu.c
index ed3a5441a47e..8934a54792be 100644
--- a/net/bridge/br_stp_bpdu.c
+++ b/net/bridge/br_stp_bpdu.c
@@ -17,6 +17,7 @@
 #include <linux/netfilter_bridge.h>
 #include <linux/etherdevice.h>
 #include <linux/llc.h>
+#include <net/llc.h>
 #include <net/llc_pdu.h>
 
 #include "br_private.h"
@@ -24,36 +25,31 @@
 
 #define STP_HZ          256
 
-static void br_send_bpdu(struct net_bridge_port *p, unsigned char *data, int length)
+#define LLC_RESERVE sizeof(struct llc_pdu_un)
+
+static void br_send_bpdu(struct net_bridge_port *p,
+                         const unsigned char *data, int length)
 {
-        struct net_device *dev;
         struct sk_buff *skb;
-        int size;
 
         if (!p->br->stp_enabled)
                 return;
 
-        size = length + 2*ETH_ALEN + 2;
-        if (size < 60)
-                size = 60;
-
-        dev = p->dev;
-
-        if ((skb = dev_alloc_skb(size)) == NULL) {
-                printk(KERN_INFO "br: memory squeeze!\n");
+        skb = dev_alloc_skb(length+LLC_RESERVE);
+        if (!skb)
                 return;
-        }
 
-        skb->dev = dev;
+        skb->dev = p->dev;
         skb->protocol = htons(ETH_P_802_2);
-        skb->mac.raw = skb_put(skb, size);
-        memcpy(skb->mac.raw, p->br->group_addr, ETH_ALEN);
-        memcpy(skb->mac.raw+ETH_ALEN, dev->dev_addr, ETH_ALEN);
-        skb->mac.raw[2*ETH_ALEN] = 0;
-        skb->mac.raw[2*ETH_ALEN+1] = length;
-        skb->nh.raw = skb->mac.raw + 2*ETH_ALEN + 2;
-        memcpy(skb->nh.raw, data, length);
-        memset(skb->nh.raw + length, 0xa5, size - length - 2*ETH_ALEN - 2);
+
+        skb_reserve(skb, LLC_RESERVE);
+        memcpy(__skb_put(skb, length), data, length);
+
+        llc_pdu_header_init(skb, LLC_PDU_TYPE_U, LLC_SAP_BSPAN,
+                            LLC_SAP_BSPAN, LLC_PDU_CMD);
+        llc_pdu_init_as_ui_cmd(skb);
+
+        llc_mac_hdr_init(skb, p->dev->dev_addr, p->br->group_addr);
 
         NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
                 dev_queue_xmit);
@@ -76,60 +72,54 @@ static inline int br_get_ticks(const unsigned char *src)
 /* called under bridge lock */
 void br_send_config_bpdu(struct net_bridge_port *p, struct br_config_bpdu *bpdu)
 {
-        unsigned char buf[38];
-
-        buf[0] = 0x42;
-        buf[1] = 0x42;
-        buf[2] = 0x03;
-        buf[3] = 0;
-        buf[4] = 0;
-        buf[5] = 0;
-        buf[6] = BPDU_TYPE_CONFIG;
-        buf[7] = (bpdu->topology_change ? 0x01 : 0) |
+        unsigned char buf[35];
+
+        buf[0] = 0;
+        buf[1] = 0;
+        buf[2] = 0;
+        buf[3] = BPDU_TYPE_CONFIG;
+        buf[4] = (bpdu->topology_change ? 0x01 : 0) |
                 (bpdu->topology_change_ack ? 0x80 : 0);
-        buf[8] = bpdu->root.prio[0];
-        buf[9] = bpdu->root.prio[1];
-        buf[10] = bpdu->root.addr[0];
-        buf[11] = bpdu->root.addr[1];
-        buf[12] = bpdu->root.addr[2];
-        buf[13] = bpdu->root.addr[3];
-        buf[14] = bpdu->root.addr[4];
-        buf[15] = bpdu->root.addr[5];
-        buf[16] = (bpdu->root_path_cost >> 24) & 0xFF;
-        buf[17] = (bpdu->root_path_cost >> 16) & 0xFF;
-        buf[18] = (bpdu->root_path_cost >> 8) & 0xFF;
-        buf[19] = bpdu->root_path_cost & 0xFF;
-        buf[20] = bpdu->bridge_id.prio[0];
-        buf[21] = bpdu->bridge_id.prio[1];
-        buf[22] = bpdu->bridge_id.addr[0];
-        buf[23] = bpdu->bridge_id.addr[1];
-        buf[24] = bpdu->bridge_id.addr[2];
-        buf[25] = bpdu->bridge_id.addr[3];
-        buf[26] = bpdu->bridge_id.addr[4];
-        buf[27] = bpdu->bridge_id.addr[5];
-        buf[28] = (bpdu->port_id >> 8) & 0xFF;
-        buf[29] = bpdu->port_id & 0xFF;
-
-        br_set_ticks(buf+30, bpdu->message_age);
-        br_set_ticks(buf+32, bpdu->max_age);
-        br_set_ticks(buf+34, bpdu->hello_time);
-        br_set_ticks(buf+36, bpdu->forward_delay);
-
-        br_send_bpdu(p, buf, 38);
+        buf[5] = bpdu->root.prio[0];
+        buf[6] = bpdu->root.prio[1];
+        buf[7] = bpdu->root.addr[0];
+        buf[8] = bpdu->root.addr[1];
+        buf[9] = bpdu->root.addr[2];
+        buf[10] = bpdu->root.addr[3];
+        buf[11] = bpdu->root.addr[4];
+        buf[12] = bpdu->root.addr[5];
+        buf[13] = (bpdu->root_path_cost >> 24) & 0xFF;
+        buf[14] = (bpdu->root_path_cost >> 16) & 0xFF;
+        buf[15] = (bpdu->root_path_cost >> 8) & 0xFF;
+        buf[16] = bpdu->root_path_cost & 0xFF;
+        buf[17] = bpdu->bridge_id.prio[0];
+        buf[18] = bpdu->bridge_id.prio[1];
+        buf[19] = bpdu->bridge_id.addr[0];
+        buf[20] = bpdu->bridge_id.addr[1];
+        buf[21] = bpdu->bridge_id.addr[2];
+        buf[22] = bpdu->bridge_id.addr[3];
+        buf[23] = bpdu->bridge_id.addr[4];
+        buf[24] = bpdu->bridge_id.addr[5];
+        buf[25] = (bpdu->port_id >> 8) & 0xFF;
+        buf[26] = bpdu->port_id & 0xFF;
+
+        br_set_ticks(buf+27, bpdu->message_age);
+        br_set_ticks(buf+29, bpdu->max_age);
+        br_set_ticks(buf+31, bpdu->hello_time);
+        br_set_ticks(buf+33, bpdu->forward_delay);
+
+        br_send_bpdu(p, buf, 35);
 }
 
 /* called under bridge lock */
 void br_send_tcn_bpdu(struct net_bridge_port *p)
 {
-        unsigned char buf[7];
-
-        buf[0] = 0x42;
-        buf[1] = 0x42;
-        buf[2] = 0x03;
-        buf[3] = 0;
-        buf[4] = 0;
-        buf[5] = 0;
-        buf[6] = BPDU_TYPE_TCN;
+        unsigned char buf[4];
+
+        buf[0] = 0;
+        buf[1] = 0;
+        buf[2] = 0;
+        buf[3] = BPDU_TYPE_TCN;
         br_send_bpdu(p, buf, 7);
 }