From 36bbfc704c7d2153537751e24413db9b9c97bc58 Mon Sep 17 00:00:00 2001
From: Pavel Machek <pavel@ucw.cz>
Date: Mon, 19 Apr 1999 18:41:56 +0000
Subject: [PATCH] Updated filters: they now actually see IP/pxlen of net being
 filtered, gateway, and who told us, so they can do usefull jobs from now on.

---
 bird.conf             |  8 +++++---
 conf/confbase.Y       |  2 +-
 doc/bird.conf.example |  1 +
 filter/config.Y       | 10 ++++++++++
 filter/filter.c       | 33 +++++++++++++++++++++++++++++++++
 proto/rip/rip.c       |  5 -----
 6 files changed, 50 insertions(+), 9 deletions(-)

diff --git a/bird.conf b/bird.conf
index 2129bab1..850b53e3 100644
--- a/bird.conf
+++ b/bird.conf
@@ -32,15 +32,16 @@ int i;
 	print "        false = " 1.2.3.4 ~ [ 1.2.3.3, 1.2.3.5 ];
 	
 	print "done";
-	quitbird;
+#	quitbird;
 	print "*** FAIL: this is unreachable"; 
 }
 
 filter testf 
 int j; 
 { 
-	j = const(4321); 
-	print j;
+	print "Heya, filtering route to " rta.net.ip " prefixlen " rta.net.len;
+	print "This route was from " rta.from;
+	accept;
 }
 
 protocol rip MyRIP_test {
@@ -50,6 +51,7 @@ protocol rip MyRIP_test {
 	period 5;
 	garbagetime 30;
 	interface "*";
+	export filter testf;
 }
 
 protocol device {
diff --git a/conf/confbase.Y b/conf/confbase.Y
index f65a9f6b..522a1803 100644
--- a/conf/confbase.Y
+++ b/conf/confbase.Y
@@ -39,7 +39,7 @@ CF_DECLS
 
 %type <i> expr bool pxlen
 
-%nonassoc '=' '<' '>' '~' ELSE IF
+%nonassoc '=' '<' '>' '~' ELSE IF '.'
 %left '+' '-'
 %left '*' '/' '%'
 %left '!'
diff --git a/doc/bird.conf.example b/doc/bird.conf.example
index c1bce781..6580ee7a 100644
--- a/doc/bird.conf.example
+++ b/doc/bird.conf.example
@@ -14,6 +14,7 @@
 #protocol rip MyRIP_test {
 #	preference xyzzy;
 #	debug all;
+#	import filter okay;
 #}
 
 protocol direct {
diff --git a/filter/config.Y b/filter/config.Y
index 4f910c26..4fd18157 100644
--- a/filter/config.Y
+++ b/filter/config.Y
@@ -23,6 +23,9 @@ CF_KEYWORDS(FUNCTION, PRINT, CONST,
 	INT, BOOL, IP, PREFIX, PAIR, SET, STRING,
 	IF, THEN, ELSE,
 	TRUE, FALSE,
+	RTA, FROM, GW, NET,
+	LEN,
+	IMPOSSIBLE,
 	FILTER
 	)
 
@@ -179,6 +182,13 @@ term:
      }
    }
  | constant { $$ = $1; }
+ | RTA '.' FROM { $$ = f_new_inst(); $$->code = 'a'; $$->a1.i = T_IP; $$->a2.i = OFFSETOF(struct rta, from); }
+
+ | RTA '.' GW { $$ = f_new_inst(); $$->code = 'a'; $$->a1.i = T_IP; $$->a2.i = OFFSETOF(struct rta, gw); }
+ | RTA '.' NET  { $$ = f_new_inst(); $$->code = 'a'; $$->a1.i = T_PREFIX; $$->a2.i = 0x12345678; }
+
+ | term '.' IP { $$ = f_new_inst(); $$->code = 'cp'; $$->a1.p = $1; $$->a2.i = T_IP; }
+ | term '.' LEN { $$ = f_new_inst(); $$->code = 'cp'; $$->a1.p = $1; $$->a2.i = T_INT; }
  ;
 
 break_command:
diff --git a/filter/filter.c b/filter/filter.c
index c6c5c5af..7afae437 100644
--- a/filter/filter.c
+++ b/filter/filter.c
@@ -93,6 +93,8 @@ val_print(struct f_val v)
   printf( buf );
 }
 
+static struct rte **f_rte;
+
 static struct f_val
 interpret(struct f_inst *what)
 {
@@ -218,6 +220,36 @@ interpret(struct f_inst *what)
       bug( "unknown return type: can not happen");
     }
     break;
+  case 'a':	/* rta access */
+    {
+      struct rta *rta = (*f_rte)->attrs;
+      res.type = what->a1.i;
+      switch(res.type) {
+      case T_IP:
+	res.val.ip = * (ip_addr *) ((char *) rta + what->a2.i);
+	break;
+      case T_PREFIX:	/* Warning: this works only for prefix of network */
+	{
+	  res.val.px.ip = (*f_rte)->net->n.prefix;
+	  res.val.px.len = (*f_rte)->net->n.pxlen;
+	  break;
+	}
+      default:
+	bug( "Invalid type for rta access" );
+      }
+    }
+    break;
+  case 'cp':	/* Convert prefix to ... */
+    ONEARG;
+    if (v1.type != T_PREFIX)
+      runtime( "Can not convert non-prefix this way" );
+    res.type = what->a2.i;
+    switch(res.type) {
+    case T_INT:	res.val.i = v1.val.px.len; break;
+    case T_IP: res.val.ip = v1.val.px.ip; break;
+    default: bug( "Unknown prefix to conversion\n" );
+    }
+    break;
   default:
     bug( "Unknown instruction %d (%c)", what->code, what->code & 0xff);
   }
@@ -233,6 +265,7 @@ f_run(struct filter *filter, struct rte **rte, struct ea_list **tmp_attrs, struc
   struct f_val res;
   debug( "Running filter `%s'...", filter->name );
 
+  f_rte = rte;
   inst = filter->root;
   res = interpret(inst);
   if (res.type != T_RETURN)
diff --git a/proto/rip/rip.c b/proto/rip/rip.c
index cfaaa4c3..24d2e82b 100644
--- a/proto/rip/rip.c
+++ b/proto/rip/rip.c
@@ -69,11 +69,6 @@ rip_tx( sock *s )
       return;
     }
 
-    if (c->done) {
-      DBG( "looks like I'm done!\n" );
-      return;
-    }
-
     DBG( "Preparing packet to send: " );
 
     packet->heading.command = RIPCMD_RESPONSE;