packets: Generalize reserved RSPAN protocols.

[sliver-openvswitch.git] / lib / packets.c

diff --git a/lib/packets.c b/lib/packets.c
index 9d861da..35829fc 100644 (file)
--- a/lib/packets.c
+++ b/lib/packets.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2009, 2010, 2011, 2012 Nicira Networks.
+ * Copyright (c) 2009, 2010, 2011, 2012 Nicira, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -43,6 +43,47 @@ dpid_from_string(const char *s, uint64_t *dpidp)
     return *dpidp != 0;
 }
 
+/* Returns true if 'ea' is a reserved multicast address, that a bridge must
+ * never forward, false otherwise.  Includes some proprietary vendor protocols
+ * that shouldn't be forwarded as well.
+ *
+ * If you change this function's behavior, please update corresponding
+ * documentation in vswitch.xml at the same time. */
+bool
+eth_addr_is_reserved(const uint8_t ea[ETH_ADDR_LEN])
+{
+    struct masked_eth_addr {
+        uint8_t ea[ETH_ADDR_LEN];
+        uint8_t mask[ETH_ADDR_LEN];
+    };
+
+    static struct masked_eth_addr mea[] = {
+        { /* STP, IEEE pause frames, and other reserved protocols. */
+            {0x01, 0x08, 0xc2, 0x00, 0x00, 0x00},
+            {0xff, 0xff, 0xff, 0xff, 0xff, 0xf0}},
+
+        { /* Cisco Inter Switch Link. */
+            {0x01, 0x00, 0x0c, 0x00, 0x00, 0x00},
+            {0xff, 0xff, 0xff, 0xff, 0xff, 0xff}},
+
+        { /* Cisco protocols plus others following the same pattern:
+           *
+           * CDP, VTP, DTP, PAgP  (01-00-0c-cc-cc-cc)
+           * Spanning Tree PVSTP+ (01-00-0c-cc-cc-cd)
+           * STP Uplink Fast      (01-00-0c-cd-cd-cd) */
+            {0x01, 0x00, 0x0c, 0xcc, 0xcc, 0xcc},
+            {0xff, 0xff, 0xff, 0xfe, 0xfe, 0xfe}}};
+
+    size_t i;
+
+    for (i = 0; i < ARRAY_SIZE(mea); i++) {
+        if (eth_addr_equal_except(ea, mea[i].ea, mea[i].mask)) {
+            return true;
+        }
+    }
+    return false;
+}
+
 bool
 eth_addr_from_string(const char *s, uint8_t ea[ETH_ADDR_LEN])
 {
@@ -148,6 +189,28 @@ eth_from_hex(const char *hex, struct ofpbuf **packetp)
     return NULL;
 }
 
+void
+eth_format_masked(const uint8_t eth[ETH_ADDR_LEN],
+                  const uint8_t mask[ETH_ADDR_LEN], struct ds *s)
+{
+    ds_put_format(s, ETH_ADDR_FMT, ETH_ADDR_ARGS(eth));
+    if (mask && !eth_mask_is_exact(mask)) {
+        ds_put_format(s, "/"ETH_ADDR_FMT, ETH_ADDR_ARGS(mask));
+    }
+}
+
+void
+eth_addr_bitand(const uint8_t src[ETH_ADDR_LEN],
+                const uint8_t mask[ETH_ADDR_LEN],
+                uint8_t dst[ETH_ADDR_LEN])
+{
+    int i;
+
+    for (i = 0; i < ETH_ADDR_LEN; i++) {
+        dst[i] = src[i] & mask[i];
+    }
+}
+
 /* Given the IP netmask 'netmask', returns the number of bits of the IP address
  * that it specifies, that is, the number of 1-bits in 'netmask'.  'netmask'
  * must be a CIDR netmask (see ip_is_cidr()). */
@@ -487,12 +550,49 @@ packet_set_udp_port(struct ofpbuf *packet, ovs_be16 src, ovs_be16 dst)
 uint8_t
 packet_get_tcp_flags(const struct ofpbuf *packet, const struct flow *flow)
 {
-    /* XXX IPv6? */
-    if (flow->dl_type == htons(ETH_TYPE_IP) && packet->l4
-        && flow->nw_proto == IPPROTO_TCP && packet->l7) {
+    if ((flow->dl_type == htons(ETH_TYPE_IP) ||
+         flow->dl_type == htons(ETH_TYPE_IPV6)) &&
+        flow->nw_proto == IPPROTO_TCP && packet->l7) {
         const struct tcp_header *tcp = packet->l4;
         return TCP_FLAGS(tcp->tcp_ctl);
     } else {
         return 0;
     }
 }
+
+/* Appends a string representation of the TCP flags value 'tcp_flags'
+ * (e.g. obtained via packet_get_tcp_flags() or TCP_FLAGS) to 's', in the
+ * format used by tcpdump. */
+void
+packet_format_tcp_flags(struct ds *s, uint8_t tcp_flags)
+{
+    if (!tcp_flags) {
+        ds_put_cstr(s, "none");
+        return;
+    }
+
+    if (tcp_flags & TCP_SYN) {
+        ds_put_char(s, 'S');
+    }
+    if (tcp_flags & TCP_FIN) {
+        ds_put_char(s, 'F');
+    }
+    if (tcp_flags & TCP_PSH) {
+        ds_put_char(s, 'P');
+    }
+    if (tcp_flags & TCP_RST) {
+        ds_put_char(s, 'R');
+    }
+    if (tcp_flags & TCP_URG) {
+        ds_put_char(s, 'U');
+    }
+    if (tcp_flags & TCP_ACK) {
+        ds_put_char(s, '.');
+    }
+    if (tcp_flags & 0x40) {
+        ds_put_cstr(s, "[40]");
+    }
+    if (tcp_flags & 0x80) {
+        ds_put_cstr(s, "[80]");
+    }
+}