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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /net/bridge/br_stp_bpdu.c
downloadlinux-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz
linux-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'net/bridge/br_stp_bpdu.c')
-rw-r--r--net/bridge/br_stp_bpdu.c205
1 files changed, 205 insertions, 0 deletions
diff --git a/net/bridge/br_stp_bpdu.c b/net/bridge/br_stp_bpdu.c
new file mode 100644
index 000000000000..b91a875aca01
--- /dev/null
+++ b/net/bridge/br_stp_bpdu.c
@@ -0,0 +1,205 @@
+/*
+ * Spanning tree protocol; BPDU handling
+ * Linux ethernet bridge
+ *
+ * Authors:
+ * Lennert Buytenhek <buytenh@gnu.org>
+ *
+ * $Id: br_stp_bpdu.c,v 1.3 2001/11/10 02:35:25 davem Exp $
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/netfilter_bridge.h>
+
+#include "br_private.h"
+#include "br_private_stp.h"
+
+#define JIFFIES_TO_TICKS(j) (((j) << 8) / HZ)
+#define TICKS_TO_JIFFIES(j) (((j) * HZ) >> 8)
+
+static void br_send_bpdu(struct net_bridge_port *p, 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");
+ return;
+ }
+
+ skb->dev = dev;
+ skb->protocol = htons(ETH_P_802_2);
+ skb->mac.raw = skb_put(skb, size);
+ memcpy(skb->mac.raw, bridge_ula, 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);
+
+ NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
+ dev_queue_xmit);
+}
+
+static __inline__ void br_set_ticks(unsigned char *dest, int jiff)
+{
+ __u16 ticks;
+
+ ticks = JIFFIES_TO_TICKS(jiff);
+ dest[0] = (ticks >> 8) & 0xFF;
+ dest[1] = ticks & 0xFF;
+}
+
+static __inline__ int br_get_ticks(unsigned char *dest)
+{
+ return TICKS_TO_JIFFIES((dest[0] << 8) | dest[1]);
+}
+
+/* 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) |
+ (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);
+}
+
+/* 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;
+ br_send_bpdu(p, buf, 7);
+}
+
+static const unsigned char header[6] = {0x42, 0x42, 0x03, 0x00, 0x00, 0x00};
+
+/* NO locks */
+int br_stp_handle_bpdu(struct sk_buff *skb)
+{
+ struct net_bridge_port *p = skb->dev->br_port;
+ struct net_bridge *br = p->br;
+ unsigned char *buf;
+
+ /* need at least the 802 and STP headers */
+ if (!pskb_may_pull(skb, sizeof(header)+1) ||
+ memcmp(skb->data, header, sizeof(header)))
+ goto err;
+
+ buf = skb_pull(skb, sizeof(header));
+
+ spin_lock_bh(&br->lock);
+ if (p->state == BR_STATE_DISABLED
+ || !(br->dev->flags & IFF_UP)
+ || !br->stp_enabled)
+ goto out;
+
+ if (buf[0] == BPDU_TYPE_CONFIG) {
+ struct br_config_bpdu bpdu;
+
+ if (!pskb_may_pull(skb, 32))
+ goto out;
+
+ buf = skb->data;
+ bpdu.topology_change = (buf[1] & 0x01) ? 1 : 0;
+ bpdu.topology_change_ack = (buf[1] & 0x80) ? 1 : 0;
+
+ bpdu.root.prio[0] = buf[2];
+ bpdu.root.prio[1] = buf[3];
+ bpdu.root.addr[0] = buf[4];
+ bpdu.root.addr[1] = buf[5];
+ bpdu.root.addr[2] = buf[6];
+ bpdu.root.addr[3] = buf[7];
+ bpdu.root.addr[4] = buf[8];
+ bpdu.root.addr[5] = buf[9];
+ bpdu.root_path_cost =
+ (buf[10] << 24) |
+ (buf[11] << 16) |
+ (buf[12] << 8) |
+ buf[13];
+ bpdu.bridge_id.prio[0] = buf[14];
+ bpdu.bridge_id.prio[1] = buf[15];
+ bpdu.bridge_id.addr[0] = buf[16];
+ bpdu.bridge_id.addr[1] = buf[17];
+ bpdu.bridge_id.addr[2] = buf[18];
+ bpdu.bridge_id.addr[3] = buf[19];
+ bpdu.bridge_id.addr[4] = buf[20];
+ bpdu.bridge_id.addr[5] = buf[21];
+ bpdu.port_id = (buf[22] << 8) | buf[23];
+
+ bpdu.message_age = br_get_ticks(buf+24);
+ bpdu.max_age = br_get_ticks(buf+26);
+ bpdu.hello_time = br_get_ticks(buf+28);
+ bpdu.forward_delay = br_get_ticks(buf+30);
+
+ br_received_config_bpdu(p, &bpdu);
+ }
+
+ else if (buf[0] == BPDU_TYPE_TCN) {
+ br_received_tcn_bpdu(p);
+ }
+ out:
+ spin_unlock_bh(&br->lock);
+ err:
+ kfree_skb(skb);
+ return 0;
+}