BGP Extended communities.

4 files changed, 222 insertions, 17 deletions

diff --git a/nest/a-set.c b/nest/a-set.c
index 3cbd635..020d097 100644
--- a/nest/a-set.c
+++ b/nest/a-set.c
@@ -36,10 +36,11 @@ int_set_format(struct adata *set, int way, int from, byte *buf, unsigned int siz
 {
   u32 *z = (u32 *) set->data;
   byte *end = buf + size - 24;
+  int from2 = MAX(from, 0);
   int to = set->length / 4;
   int i;
 
-  for (i = MAX(from, 0); i < to; i++)
+  for (i = from2; i < to; i++)
     {
       if (buf > end)
 	{
@@ -50,7 +51,7 @@ int_set_format(struct adata *set, int way, int from, byte *buf, unsigned int siz
 	  return i;
 	}
 
-      if (i > from)
+      if (i > from2)
 	*buf++ = ' ';
 
       if (way)
@@ -63,16 +64,116 @@ int_set_format(struct adata *set, int way, int from, byte *buf, unsigned int siz
 }
 
 int
+ec_format(byte *buf, u64 ec)
+{
+  u32 type, key, val;
+  char tbuf[16], *kind;
+
+  type = ec >> 48;
+  switch (type & 0xf0ff)
+    {
+    case EC_RT: kind = "rt"; break;
+    case EC_RO: kind = "ro"; break;
+
+    default:
+      kind = tbuf;
+      bsprintf(kind, "unknown 0x%x", type);
+    }
+
+  switch (ec >> 56)
+    {
+      /* RFC 4360 3.1.  Two-Octet AS Specific Extended Community */
+    case 0x00:
+    case 0x40:
+      key = (ec >> 32) & 0xFFFF;
+      val = ec;
+      return bsprintf(buf, "(%s, %u, %u)", kind, key, val);
+
+      /* RFC 4360 3.2.  IPv4 Address Specific Extended Community */
+    case 0x01:
+    case 0x41:
+      key = ec >> 16;
+      val = ec & 0xFFFF;
+      return bsprintf(buf, "(%s, %R, %u)", kind, key, val);
+
+      /* RFC 5668  4-Octet AS Specific BGP Extended Community */
+    case 0x02:
+    case 0x42:
+      key = ec >> 16;
+      val = ec & 0xFFFF;
+      return bsprintf(buf, "(%s, %u, %u)", kind, key, val);
+
+      /* Generic format for unknown kinds of extended communities */
+    default:
+      key = ec >> 32;
+      val = ec;
+      return bsprintf(buf, "(generic, 0x%x, 0x%x)", key, val);
+    }
+
+}
+
+int
+ec_set_format(struct adata *set, int from, byte *buf, unsigned int size)
+{
+  u32 *z = int_set_get_data(set);
+  byte *end = buf + size - 24;
+  int from2 = MAX(from, 0);
+  int to = int_set_get_size(set);
+  int i;
+
+  for (i = from2; i < to; i += 2)
+    {
+      if (buf > end)
+	{
+	  if (from < 0)
+	    strcpy(buf, " ...");
+	  else
+	    *buf = 0;
+	  return i;
+	}
+
+      if (i > from2)
+	*buf++ = ' ';
+
+      buf += ec_format(buf, ec_get(z, i));
+    }
+  *buf = 0;
+  return 0;
+}
+
+int
 int_set_contains(struct adata *list, u32 val)
 {
   if (!list)
     return 0;
 
   u32 *l = (u32 *) list->data;
-  unsigned int i;
-  for (i=0; i<list->length/4; i++)
+  int len = int_set_get_size(list);
+  int i;
+
+  for (i = 0; i < len; i++)
     if (*l++ == val)
       return 1;
+
+  return 0;
+}
+
+int
+ec_set_contains(struct adata *list, u64 val)
+{
+  if (!list)
+    return 0;
+
+  u32 *l = int_set_get_data(list);
+  int len = int_set_get_size(list);
+  u32 eh = ec_hi(val);
+  u32 el = ec_lo(val);
+  int i;
+
+  for (i=0; i < len; i += 2)
+    if (l[i] == eh && l[i+1] == el)
+      return 1;
+
   return 0;
 }
 
@@ -86,7 +187,7 @@ int_set_add(struct linpool *pool, struct adata *list, u32 val)
     return list;
 
   len = list ? list->length : 0;
-  res = lp_alloc(pool, len + sizeof(struct adata) + 4);
+  res = lp_alloc(pool, sizeof(struct adata) + len + 4);
   res->length = len + 4;
   * (u32 *) res->data = val;
   if (list)
@@ -95,23 +196,71 @@ int_set_add(struct linpool *pool, struct adata *list, u32 val)
 }
 
 struct adata *
-int_set_del(struct linpool *pool, struct adata *list, u32 val)
+ec_set_add(struct linpool *pool, struct adata *list, u64 val)
 {
-  struct adata *res;
-  u32 *l, *k;
-  unsigned int i;
+  if (ec_set_contains(list, val))
+    return list;
+
+  int olen = list ? list->length : 0;
+  struct adata *res = lp_alloc(pool, sizeof(struct adata) + olen + 8);
+  res->length = olen + 8;
+
+  if (list)
+    memcpy(res->data, list->data, list->length);
+
+  u32 *l = (u32 *) (res->data + res->length - 8);
+  l[0] = ec_hi(val);
+  l[1] = ec_lo(val);
+
+  return res;
+}
+
 
+struct adata *
+int_set_del(struct linpool *pool, struct adata *list, u32 val)
+{
   if (!int_set_contains(list, val))
     return list;
 
-  res = lp_alloc(pool, list->length + sizeof(struct adata) - 4);
-  res->length = list->length-4;
+  struct adata *res;
+  res = lp_alloc(pool, sizeof(struct adata) + list->length - 4);
+  res->length = list->length - 4;
+
+  u32 *l = int_set_get_data(list);
+  u32 *k = int_set_get_data(res);
+  int len = int_set_get_size(list);
+  int i;
 
-  l = (u32 *) list->data;
-  k = (u32 *) res->data;
-  for (i=0; i<list->length/4; i++)
+  for (i = 0; i < len; i++)
     if (l[i] != val)
       *k++ = l[i];
 
   return res;
 }
+
+struct adata *
+ec_set_del(struct linpool *pool, struct adata *list, u64 val)
+{
+  if (!ec_set_contains(list, val))
+    return list;
+
+  struct adata *res;
+  res = lp_alloc(pool, sizeof(struct adata) + list->length - 8);
+  res->length = list->length - 8;
+
+  u32 *l = int_set_get_data(list);
+  u32 *k = int_set_get_data(res);
+  int len = int_set_get_size(list);
+  u32 eh = ec_hi(val);
+  u32 el = ec_lo(val);
+  int i;
+
+  for (i=0; i < len; i += 2)
+    if (! (l[i] == eh && l[i+1] == el))
+      {
+	*k++ = l[i];
+	*k++ = l[i+1];
+      }
+
+  return res;
+}
diff --git a/nest/attrs.h b/nest/attrs.h
index 6ce5755..85e4e59 100644
--- a/nest/attrs.h
+++ b/nest/attrs.h
@@ -50,12 +50,52 @@ int as_path_match(struct adata *path, struct f_path_mask *mask);
 
 /* a-set.c */
 
+
+/* Extended Community subtypes (kinds) */
+#define EC_RT 0x0002
+#define EC_RO 0x0003
+
+#define EC_GENERIC 0xFFFF
+
+/* Transitive bit (for first u32 half of EC) */
+#define EC_TBIT 0x40000000
+
+
+static inline int int_set_get_size(struct adata *list)
+{ return list->length / 4; }
+
+static inline u32 *int_set_get_data(struct adata *list)
+{ return (u32 *) list->data; }
+
+static inline u32 ec_hi(u64 ec) { return ec >> 32; }
+static inline u32 ec_lo(u64 ec) { return ec; }
+static inline u64 ec_get(const u32 *l, int i)
+{ return (((u64) l[i]) << 32) | l[i+1]; }
+
+/* RFC 4360 3.1.  Two-Octet AS Specific Extended Community */
+static inline u64 ec_as2(u64 kind, u64 key, u64 val)
+{ return ((kind | 0x0000) << 48) | (key << 32) | val; }
+
+/* RFC 5668  4-Octet AS Specific BGP Extended Community */
+static inline u64 ec_as4(u64 kind, u64 key, u64 val)
+{ return ((kind | 0x0200) << 48) | (key << 16) | val; }
+
+/* RFC 4360 3.2.  IPv4 Address Specific Extended Community */
+static inline u64 ec_ip4(u64 kind, u64 key, u64 val)
+{ return ((kind | 0x0100) << 48) | (key << 16) | val; }
+
+static inline u64 ec_generic(u64 key, u64 val)
+{ return (key << 32) | val; }
+
 int int_set_format(struct adata *set, int way, int from, byte *buf, unsigned int size);
-struct adata *int_set_add(struct linpool *pool, struct adata *list, u32 val);
+int ec_format(byte *buf, u64 ec);
+int ec_set_format(struct adata *set, int from, byte *buf, unsigned int size);
 int int_set_contains(struct adata *list, u32 val);
+int ec_set_contains(struct adata *list, u64 val);
+struct adata *int_set_add(struct linpool *pool, struct adata *list, u32 val);
+struct adata *ec_set_add(struct linpool *pool, struct adata *list, u64 val);
 struct adata *int_set_del(struct linpool *pool, struct adata *list, u32 val);
+struct adata *ec_set_del(struct linpool *pool, struct adata *list, u64 val);
 
-static inline int int_set_get_size(struct adata *list)
-{ return list->length / 4; }
 
 #endif
diff --git a/nest/route.h b/nest/route.h
index c77fe41..641b924 100644
--- a/nest/route.h
+++ b/nest/route.h
@@ -363,6 +363,7 @@ typedef struct eattr {
 #define EAF_TYPE_ROUTER_ID 0x05		/* Router ID (IPv4 address) */
 #define EAF_TYPE_AS_PATH 0x06		/* BGP AS path (encoding per RFC 1771:4.3) */
 #define EAF_TYPE_INT_SET 0x0a		/* Set of u32's (e.g., a community list) */
+#define EAF_TYPE_EC_SET 0x0e		/* Set of pairs of u32's - ext. community list */
 #define EAF_TYPE_UNDEF 0x0f		/* `force undefined' entry */
 #define EAF_EMBEDDED 0x01		/* Data stored in eattr.u.data (part of type spec) */
 #define EAF_VAR_LENGTH 0x02		/* Attribute length is variable (part of type spec) */
diff --git a/nest/rt-attr.c b/nest/rt-attr.c
index 486a543..5a78f16 100644
--- a/nest/rt-attr.c
+++ b/nest/rt-attr.c
@@ -465,6 +465,18 @@ ea_show_int_set(struct cli *c, struct adata *ad, int way, byte *pos, byte *buf,
     }
 }
 
+static inline void
+ea_show_ec_set(struct cli *c, struct adata *ad, byte *pos, byte *buf, byte *end)
+{
+  int i = ec_set_format(ad, 0, pos, end - pos);
+  cli_printf(c, -1012, "%s", buf);
+  while (i)
+    {
+      i = ec_set_format(ad, i, buf, end - buf - 1);
+      cli_printf(c, -1012, "\t%s", buf);
+    }
+}
+
 /**
  * ea_show - print an &eattr to CLI
  * @c: destination CLI
@@ -523,6 +535,9 @@ ea_show(struct cli *c, eattr *e)
 	case EAF_TYPE_INT_SET:
 	  ea_show_int_set(c, ad, 1, pos, buf, end);
 	  return;
+	case EAF_TYPE_EC_SET:
+	  ea_show_ec_set(c, ad, pos, buf, end);
+	  return;
 	case EAF_TYPE_UNDEF:
 	default:
 	  bsprintf(pos, "<type %02x>", e->type);