BGP: Support for large communities

Add support for large communities (draft-ietf-idr-large-community),
96bit alternative to RFC 1997 communities.

Thanks to Matt Griswold for the original patch.

4 files changed, 243 insertions, 6 deletions

diff --git a/filter/config.Y b/filter/config.Y
index 9fffd651..79e274ab 100644
--- a/filter/config.Y
+++ b/filter/config.Y
@@ -36,6 +36,7 @@ f_valid_set_type(int type)
   case T_ENUM:
   case T_IP:
   case T_EC:
+  case T_LC:
     return 1;
 
   default:
@@ -148,6 +149,9 @@ f_generate_empty(struct f_inst *dyn)
     case EAF_TYPE_EC_SET:
       e->aux = T_ECLIST;
       break;
+    case EAF_TYPE_LC_SET:
+      e->aux = T_LCLIST;
+      break;
     default:
       cf_error("Can't empty that attribute");
   }
@@ -268,14 +272,44 @@ f_generate_ec(u16 kind, struct f_inst *tk, struct f_inst *tv)
   return rv;
 }
 
+static inline struct f_inst *
+f_generate_lc(struct f_inst *t1, struct f_inst *t2, struct f_inst *t3)
+{
+  struct f_inst *rv;
+
+  if ((t1->code == 'c') && (t2->code == 'c') && (t3->code == 'c')) {
+    if ((t1->aux != T_INT) || (t2->aux != T_INT) || (t3->aux != T_INT))
+      cf_error( "LC - Can't operate with value of non-integer type in tuple constructor");
+
+    rv = f_new_inst();
+    rv->code = 'C';
+
+    NEW_F_VAL;
+    rv->a1.p = val;
+    val->type = T_LC;
+    val->val.lc = (lcomm) { t1->a2.i, t2->a2.i, t3->a2.i };
+  }
+  else
+  {
+    rv = cfg_allocz(sizeof(struct f_inst3));
+    rv->lineno = ifs->lino;
+    rv->code = P('m','l');
+    rv->a1.p = t1;
+    rv->a2.p = t2;
+    INST3(rv).p = t3;
+  }
+
+  return rv;
+}
+
 
 
 CF_DECLS
 
 CF_KEYWORDS(FUNCTION, PRINT, PRINTN, UNSET, RETURN,
 	ACCEPT, REJECT, ERROR, QUITBIRD,
-	INT, BOOL, IP, PREFIX, PAIR, QUAD, EC,
-	SET, STRING, BGPMASK, BGPPATH, CLIST, ECLIST,
+	INT, BOOL, IP, PREFIX, PAIR, QUAD, EC, LC,
+	SET, STRING, BGPMASK, BGPPATH, CLIST, ECLIST, LCLIST,
 	IF, THEN, ELSE, CASE,
 	TRUE, FALSE, RT, RO, UNKNOWN, GENERIC,
 	FROM, GW, NET, MASK, PROTO, SOURCE, SCOPE, CAST, DEST, IFNAME, IFINDEX,
@@ -327,17 +361,20 @@ type:
  | PAIR { $$ = T_PAIR; }
  | QUAD { $$ = T_QUAD; }
  | EC { $$ = T_EC; }
+ | LC { $$ = T_LC; }
  | STRING { $$ = T_STRING; }
  | BGPMASK { $$ = T_PATH_MASK; }
  | BGPPATH { $$ = T_PATH; }
  | CLIST { $$ = T_CLIST; }
  | ECLIST { $$ = T_ECLIST; }
+ | LCLIST { $$ = T_LCLIST; }
  | type SET { 
 	switch ($1) {
 	  case T_INT:
 	  case T_PAIR:
 	  case T_QUAD:
 	  case T_EC:
+	  case T_LC:
 	  case T_IP:
 	       $$ = T_SET;
 	       break;
@@ -657,6 +694,7 @@ constant:
 constructor:
    '(' term ',' term ')' { $$ = f_generate_dpair($2, $4); }
  | '(' ec_kind ',' term ',' term ')' { $$ = f_generate_ec($2, $4, $6); }
+ | '(' term ',' term ',' term ')' { $$ = f_generate_lc($2, $4, $6); }
  ;
 
 
@@ -767,6 +805,7 @@ term:
  | '+' EMPTY '+' { $$ = f_new_inst(); $$->code = 'E'; $$->aux = T_PATH; }
  | '-' EMPTY '-' { $$ = f_new_inst(); $$->code = 'E'; $$->aux = T_CLIST; }
  | '-' '-' EMPTY '-' '-' { $$ = f_new_inst(); $$->code = 'E'; $$->aux = T_ECLIST; }
+ | '-' '-' '-' EMPTY '-' '-' '-' { $$ = f_new_inst(); $$->code = 'E'; $$->aux = T_LCLIST; }
  | PREPEND '(' term ',' term ')' { $$ = f_new_inst(); $$->code = P('A','p'); $$->a1.p = $3; $$->a2.p = $5; } 
  | ADD '(' term ',' term ')' { $$ = f_new_inst(); $$->code = P('C','a'); $$->a1.p = $3; $$->a2.p = $5; $$->aux = 'a'; } 
  | DELETE '(' term ',' term ')' { $$ = f_new_inst(); $$->code = P('C','a'); $$->a1.p = $3; $$->a2.p = $5; $$->aux = 'd'; }
diff --git a/filter/filter.c b/filter/filter.c
index 2f5f00d8..510303a7 100644
--- a/filter/filter.c
+++ b/filter/filter.c
@@ -106,6 +106,18 @@ u64_cmp(u64 i1, u64 i2)
   return (int)(i1 > i2) - (int)(i1 < i2);
 }
 
+static inline int
+lcomm_cmp(lcomm v1, lcomm v2)
+{
+  if (v1.asn != v2.asn)
+    return (v1.asn > v2.asn) ? 1 : -1;
+  if (v1.ldp1 != v2.ldp1)
+    return (v1.ldp1 > v2.ldp1) ? 1 : -1;
+  if (v1.ldp2 != v2.ldp2)
+    return (v1.ldp2 > v2.ldp2) ? 1 : -1;
+  return 0;
+}
+
 /**
  * val_compare - compare two values
  * @v1: first value
@@ -149,6 +161,8 @@ val_compare(struct f_val v1, struct f_val v2)
     return uint_cmp(v1.val.i, v2.val.i);
   case T_EC:
     return u64_cmp(v1.val.ec, v2.val.ec);
+  case T_LC:
+    return lcomm_cmp(v1.val.lc, v2.val.lc);
   case T_IP:
     return ipa_compare(v1.val.px.ip, v2.val.px.ip);
   case T_PREFIX:
@@ -214,6 +228,7 @@ val_same(struct f_val v1, struct f_val v2)
   case T_PATH:
   case T_CLIST:
   case T_ECLIST:
+  case T_LCLIST:
     return adata_same(v1.val.ad, v2.val.ad);
   case T_SET:
     return same_tree(v1.val.t, v2.val.t);
@@ -266,6 +281,10 @@ static inline int
 eclist_set_type(struct f_tree *set)
 { return set->from.type == T_EC; }
 
+static inline int
+lclist_set_type(struct f_tree *set)
+{ return set->from.type == T_LC; }
+
 static int
 clist_match_set(struct adata *clist, struct f_tree *set)
 {
@@ -311,6 +330,30 @@ eclist_match_set(struct adata *list, struct f_tree *set)
   return 0;
 }
 
+static int
+lclist_match_set(struct adata *list, struct f_tree *set)
+{
+  if (!list)
+    return 0;
+
+  if (!lclist_set_type(set))
+    return CMP_ERROR;
+
+  struct f_val v;
+  u32 *l = int_set_get_data(list);
+  int len = int_set_get_size(list);
+  int i;
+
+  v.type = T_LC;
+  for (i = 0; i < len; i += 3) {
+    v.val.lc = lc_get(l, i);
+    if (find_tree(set, v))
+      return 1;
+  }
+
+  return 0;
+}
+
 static struct adata *
 clist_filter(struct linpool *pool, struct adata *list, struct f_val set, int pos)
 {
@@ -380,6 +423,38 @@ eclist_filter(struct linpool *pool, struct adata *list, struct f_val set, int po
   return res;
 }
 
+static struct adata *
+lclist_filter(struct linpool *pool, struct adata *list, struct f_val set, int pos)
+{
+  if (!list)
+    return NULL;
+
+  int tree = (set.type == T_SET);	/* 1 -> set is T_SET, 0 -> set is T_CLIST */
+  struct f_val v;
+
+  int len = int_set_get_size(list);
+  u32 *l = int_set_get_data(list);
+  u32 tmp[len];
+  u32 *k = tmp;
+  int i;
+
+  v.type = T_LC;
+  for (i = 0; i < len; i += 3) {
+    v.val.lc = lc_get(l, i);
+    /* pos && member(val, set) || !pos && !member(val, set),  member() depends on tree */
+    if ((tree ? !!find_tree(set.val.t, v) : lc_set_contains(set.val.ad, v.val.lc)) == pos)
+      k = lc_copy(k, l+i);
+  }
+
+  int nl = (k - tmp) * 4;
+  if (nl == list->length)
+    return list;
+
+  struct adata *res = adata_empty(pool, nl);
+  memcpy(res->data, tmp, nl);
+  return res;
+}
+
 /**
  * val_in_range - implement |~| operator
  * @v1: element
@@ -407,6 +482,9 @@ val_in_range(struct f_val v1, struct f_val v2)
   if ((v1.type == T_EC) && (v2.type == T_ECLIST))
     return ec_set_contains(v2.val.ad, v1.val.ec);
 
+  if ((v1.type == T_LC) && (v2.type == T_LCLIST))
+    return lc_set_contains(v2.val.ad, v1.val.lc);
+
   if ((v1.type == T_STRING) && (v2.type == T_STRING))
     return patmatch(v2.val.s, v1.val.s);
 
@@ -433,6 +511,9 @@ val_in_range(struct f_val v1, struct f_val v2)
   if (v1.type == T_ECLIST)
     return eclist_match_set(v1.val.ad, v2.val.t);
 
+  if (v1.type == T_LCLIST)
+    return lclist_match_set(v1.val.ad, v2.val.t);
+
   if (v1.type == T_PATH)
     return as_path_match_set(v1.val.ad, v2.val.t);
 
@@ -457,12 +538,14 @@ val_format(struct f_val v, buffer *buf)
   case T_PAIR:	buffer_print(buf, "(%u,%u)", v.val.i >> 16, v.val.i & 0xffff); return;
   case T_QUAD:	buffer_print(buf, "%R", v.val.i); return;
   case T_EC:	ec_format(buf2, v.val.ec); buffer_print(buf, "%s", buf2); return;
+  case T_LC:	lc_format(buf2, v.val.lc); buffer_print(buf, "%s", buf2); return;
   case T_PREFIX_SET: trie_format(v.val.ti, buf); return;
   case T_SET:	tree_format(v.val.t, buf); return;
   case T_ENUM:	buffer_print(buf, "(enum %x)%u", v.type, v.val.i); return;
   case T_PATH:	as_path_format(v.val.ad, buf2, 1000); buffer_print(buf, "(path %s)", buf2); return;
   case T_CLIST:	int_set_format(v.val.ad, 1, -1, buf2, 1000); buffer_print(buf, "(clist %s)", buf2); return;
   case T_ECLIST: ec_set_format(v.val.ad, -1, buf2, 1000); buffer_print(buf, "(eclist %s)", buf2); return;
+  case T_LCLIST: lc_set_format(v.val.ad, -1, buf2, 1000); buffer_print(buf, "(lclist %s)", buf2); return;
   case T_PATH_MASK: pm_format(v.val.path_mask, buf); return;
   default:	buffer_print(buf, "[unknown type %x]", v.type); return;
   }
@@ -656,6 +739,7 @@ interpret(struct f_inst *what)
 	runtime("Can't operate with value of non-integer type in EC constructor");
       val = v2.val.i;
 
+      /* XXXX */
       res.type = T_EC;
 
       if (what->aux == EC_GENERIC) {
@@ -677,6 +761,24 @@ interpret(struct f_inst *what)
       break;
     }
 
+  case P('m','l'):
+    {
+      TWOARGS;
+
+      /* Third argument hack */
+      struct f_val v3 = interpret(INST3(what).p);
+      if (v3.type & T_RETURN)
+	return v3;
+
+      if ((v1.type != T_INT) || (v2.type != T_INT) || (v3.type != T_INT))
+	runtime( "Can't operate with value of non-integer type in LC constructor" );
+
+      res.type = T_LC;
+      res.val.lc = (lcomm) { v1.val.i, v2.val.i, v3.val.i };
+
+      break;
+    }
+
 /* Relational operators */
 
 #define COMPARE(x) \
@@ -912,6 +1014,13 @@ interpret(struct f_inst *what)
 	  break;
 	}
 
+	/* The same special case for lc_set */
+	if ((what->aux & EAF_TYPE_MASK) == EAF_TYPE_LC_SET) {
+	  res.type = T_LCLIST;
+	  res.val.ad = adata_empty(f_pool, 0);
+	  break;
+	}
+
 	/* Undefined value */
 	res.type = T_VOID;
 	break;
@@ -951,6 +1060,10 @@ interpret(struct f_inst *what)
 	res.type = T_ECLIST;
 	res.val.ad = e->u.ptr;
 	break;
+      case EAF_TYPE_LC_SET:
+	res.type = T_LCLIST;
+	res.val.ad = e->u.ptr;
+	break;
       case EAF_TYPE_UNDEF:
 	res.type = T_VOID;
 	break;
@@ -1041,6 +1154,11 @@ interpret(struct f_inst *what)
 	  runtime( "Setting eclist attribute to non-eclist value" );
 	l->attrs[0].u.ptr = v1.val.ad;
 	break;
+      case EAF_TYPE_LC_SET:
+	if (v1.type != T_LCLIST)
+	  runtime( "Setting lclist attribute to non-lclist value" );
+	l->attrs[0].u.ptr = v1.val.ad;
+	break;
       case EAF_TYPE_UNDEF:
 	if (v1.type != T_VOID)
 	  runtime( "Setting void attribute to non-void value" );
@@ -1082,6 +1200,7 @@ interpret(struct f_inst *what)
     case T_PATH:   res.val.i = as_path_getlen(v1.val.ad); break;
     case T_CLIST:  res.val.i = int_set_get_size(v1.val.ad); break;
     case T_ECLIST: res.val.i = ec_set_get_size(v1.val.ad); break;
+    case T_LCLIST: res.val.i = lc_set_get_size(v1.val.ad); break;
     default: runtime( "Prefix, path, clist or eclist expected" );
     }
     break;
@@ -1277,7 +1396,7 @@ interpret(struct f_inst *what)
       else if (v2.type == T_ECLIST)
 	arg_set = 2;
       else if (v2.type != T_EC)
-	runtime("Can't add/delete non-pair");
+	runtime("Can't add/delete non-ec");
 
       res.type = T_ECLIST;
       switch (what->aux)
@@ -1308,8 +1427,50 @@ interpret(struct f_inst *what)
 	bug("unknown Ca operation");
       }
     }
+    else if (v1.type == T_LCLIST)
+    {
+      /* Large community list */
+      int arg_set = 0;
+
+      /* v2.val is either LC or LC-set */
+      if ((v2.type == T_SET) && lclist_set_type(v2.val.t))
+	arg_set = 1;
+      else if (v2.type == T_LCLIST)
+	arg_set = 2;
+      else if (v2.type != T_LC)
+	runtime("Can't add/delete non-lc");
+
+      res.type = T_LCLIST;
+      switch (what->aux)
+      {
+      case 'a':
+	if (arg_set == 1)
+	  runtime("Can't add set");
+	else if (!arg_set)
+	  res.val.ad = lc_set_add(f_pool, v1.val.ad, v2.val.lc);
+	else
+	  res.val.ad = lc_set_union(f_pool, v1.val.ad, v2.val.ad);
+	break;
+
+      case 'd':
+	if (!arg_set)
+	  res.val.ad = lc_set_del(f_pool, v1.val.ad, v2.val.lc);
+	else
+	  res.val.ad = lclist_filter(f_pool, v1.val.ad, v2, 0);
+	break;
+
+      case 'f':
+	if (!arg_set)
+	  runtime("Can't filter lc");
+	res.val.ad = lclist_filter(f_pool, v1.val.ad, v2, 1);
+	break;
+
+      default:
+	bug("unknown Ca operation");
+      }
+    }
     else
-      runtime("Can't add/delete to non-(e)clist");
+      runtime("Can't add/delete to non-[e|l]clist");
 
     break;
 
@@ -1401,6 +1562,12 @@ i_same(struct f_inst *f1, struct f_inst *f2)
   case '~': TWOARGS; break;
   case P('d','e'): ONEARG; break;
 
+  case P('m','l'):
+    TWOARGS;
+    if (!i_same(INST3(f1).p, INST3(f2).p))
+      return 0;
+    break;
+
   case 's':
     ARG(v2, a2.p);
     {
diff --git a/filter/filter.h b/filter/filter.h
index e59c8226..e0f34e4f 100644
--- a/filter/filter.h
+++ b/filter/filter.h
@@ -38,6 +38,17 @@ struct f_inst_roa_check {
   struct roa_table_config *rtc;	
 };
 
+struct f_inst3 {
+  struct f_inst i;
+  union {
+    int i;
+    void *p;
+  } a3;
+};
+
+#define INST3(x) (((struct f_inst3 *) x)->a3)
+
+
 struct f_prefix {
   ip_addr ip;
   int len;
@@ -53,6 +64,7 @@ struct f_val {
   union {
     uint i;
     u64 ec;
+    lcomm lc;
     /*    ip_addr ip; Folded into prefix */	
     struct f_prefix px;
     char *s;
@@ -168,8 +180,10 @@ void val_format(struct f_val v, buffer *buf);
 #define T_PATH_MASK 0x23	/* mask for BGP path */
 #define T_PATH 0x24		/* BGP path */
 #define T_CLIST 0x25		/* Community list */
-#define T_ECLIST 0x26		/* Extended community list */
-#define T_EC 0x27		/* Extended community value, u64 */
+#define T_EC 0x26		/* Extended community value, u64 */
+#define T_ECLIST 0x27		/* Extended community list */
+#define T_LC 0x28		/* Large community value, lcomm */
+#define T_LCLIST 0x29		/* Large community list */
 
 #define T_RETURN 0x40
 #define T_SET 0x80
diff --git a/filter/test.conf b/filter/test.conf
index f61f0658..e8873fbf 100644
--- a/filter/test.conf
+++ b/filter/test.conf
@@ -27,6 +27,11 @@ function 'mkpair-a'(int a)
 	return (1, a);
 }
 
+function mktrip(int a)
+{
+	return (a, 2*a, 3*a);
+}
+
 function mkpath(int a; int b)
 {
 	return [= a b 3 2 1 =];
@@ -89,6 +94,7 @@ clist l;
 clist l2;
 eclist el;
 eclist el2;
+lclist ll;
 {
 	print "Entering path test...";
 	pm1 =  / 4 3 2 1 /;
@@ -203,6 +209,17 @@ eclist el2;
 	print "eclist A isect B: ", filter( el, el2 );
 	print "eclist A \  B: ", delete( el, el2 );
 
+	ll = --- empty ---;
+	ll = add(ll, (ten, 20, 30));
+	ll = add(ll, (1000, 2000, 3000));
+	ll = add(ll, mktrip(100000));
+	print "LC list (10, 20, 30) (1000, 2000, 3000) (100000, 200000, 300000):";
+	print ll;
+	print "LC len: ", el.len;
+	print "Should be true: ", mktrip(1000) ~ ll, " ", ll ~ [(5,10,15), (10,20,30)], " ", ll ~ [(10,15..25,*)], " ", ll ~ [(ten, *, *)];
+	print "Should be false: ", mktrip(100) ~ ll, " ", ll ~ [(5,10,15), (10,21,30)], " ", ll ~ [(10,21..25,*)], " ", ll ~ [(11, *, *)];
+	print "LC filtered: ", filter(ll, [(5..15, *, *), (100000, 500..500000, *)]);
+
 #	test_roa();
 }