2004-10-05 Paul Jakma <paul@dishone.st>

	* irdp_packet.c: (parse_irdp_packet) style issues.
	  Use sockopt_iphdrincl_swab_systoh.
          Try unbork the code. Checksum the ICMP data and actually
          compare it to received checksum. Check data length against
          claimed length in header.
	  Always use ntoh.. when accessing addresses, even when the
          comparison happens to be endian-safe.
	  (send_packet) minor style isues. Use
          sockopt_iphdrincl_swab_htosys.
	  (irdp_iph_hton/ntoh) IP header to/from network/host order.

diff --git a/zebra/ChangeLog b/zebra/ChangeLog
index fb8d0ab1b1226db70cc7416fd58bf4501b61c705..a6ac1fc3b22f29a78056c7abeafe4127a4376ba1 100644 (file)
--- a/zebra/ChangeLog
+++ b/zebra/ChangeLog
@@ -1,3 +1,16 @@
+2004-10-05 Paul Jakma <paul@dishone.st>
+
+       * irdp_packet.c: (parse_irdp_packet) style issues.
+         Use sockopt_iphdrincl_swab_systoh.
+          Try unbork the code. Checksum the ICMP data and actually 
+          compare it to received checksum. Check data length against
+          claimed length in header.
+         Always use ntoh.. when accessing addresses, even when the
+          comparison happens to be endian-safe.
+         (send_packet) minor style isues. Use
+          sockopt_iphdrincl_swab_htosys.
+         (irdp_iph_hton/ntoh) IP header to/from network/host order.
+
 2004-10-03 Gilad Arnold <gilad.arnold at terayon.com>
 
        * interface.c, interface.h: A new prefix tree of connected subnets is

diff --git a/zebra/irdp_packet.c b/zebra/irdp_packet.c
index 67609b31f0fee3f205b4f2ffa609a15351413c51..60604353ca60930deb6229a1c53f7677a18bbeb7 100644 (file)
--- a/zebra/irdp_packet.c
+++ b/zebra/irdp_packet.c
@@ -82,79 +82,88 @@ void parse_irdp_packet(char *p,
   struct ip *ip = (struct ip *)p ;
   struct icmphdr *icmp;
   struct in_addr src;
-  int ip_hlen, ip_len;
+  int ip_hlen, iplen, datalen;
   struct zebra_if *zi;
   struct irdp_interface *irdp;
 
   zi = ifp->info;
-  if(!zi) return;
+  if (!zi) 
+    return;
 
   irdp = &zi->irdp;
-  if(!irdp) return;
+  if (!irdp) 
+    return;
 
-  ip_hlen = ip->ip_hl*4; 
-  ip_len = ntohs(ip->ip_len);
-  len = len - ip_hlen;
+  ip_hlen = ip->ip_hl << 2;
+  
+  sockopt_iphdrincl_swab_systoh (ip);
+  
+  iplen = ip->ip_len;
+  datalen = len - ip_hlen;
   src = ip->ip_src;
 
-  if(ip_len < ICMP_MINLEN) {
-    zlog_err ("IRDP: RX ICMP packet too short from %s\n",
-             inet_ntoa (src));
-    return;
-  }
+  if (len != iplen)
+    {
+      zlog_err ("IRDP: RX length doesnt match IP length");
+      return;
+    }
 
+  if (iplen < ICMP_MINLEN) 
+    {
+      zlog_err ("IRDP: RX ICMP packet too short from %s\n",
+             inet_ntoa (src));
+      return;
+    }
+    
+  /* XXX: RAW doesnt receive link-layer, surely? ??? */
   /* Check so we don't checksum packets longer than oure RX_BUF - (ethlen +
    len of IP-header) 14+20 */
-
-  if(ip_len > IRDP_RX_BUF-34) {
-    zlog_err ("IRDP: RX ICMP packet too long from %s\n",
-             inet_ntoa (src));
-    return;
-  }
-
-
-  if (in_cksum (ip, ip_len)) {
-    zlog_warn ("IRDP: RX ICMP packet from %s. Bad checksum, silently ignored",
-              inet_ntoa (src));
-    return;
-  }
+  if (iplen > IRDP_RX_BUF-34) 
+    {
+      zlog_err ("IRDP: RX ICMP packet too long from %s\n",
+               inet_ntoa (src));
+      return;
+    }
 
   icmp = (struct icmphdr *) (p+ip_hlen);
 
-
+  /* check icmp checksum */    
+  if (in_cksum (icmp, datalen) != icmp->checksum) 
+    {
+      zlog_warn ("IRDP: RX ICMP packet from %s. Bad checksum, silently ignored",
+                 inet_ntoa (src));
+      return;
+    }
+  
   /* Handle just only IRDP */
-
-  if( icmp->type == ICMP_ROUTERADVERT);
-  else if( icmp->type == ICMP_ROUTERSOLICIT);
-  else return;
-
- 
-  if (icmp->code != 0) {
-    zlog_warn ("IRDP: RX packet type %d from %s. Bad ICMP type code, silently ignored",
-              icmp->type,
-              inet_ntoa (src));
+  if (!(icmp->type == ICMP_ROUTERADVERT
+        || icmp->type == ICMP_ROUTERSOLICIT))
     return;
-  }
-
-  if(ip->ip_dst.s_addr == INADDR_BROADCAST && 
-     irdp->flags & IF_BROADCAST);
-
-  else if ( ntohl(ip->ip_dst.s_addr) == INADDR_ALLRTRS_GROUP && 
-           ! (irdp->flags &  IF_BROADCAST));
-
-  else { /* ERROR */
-
-    zlog_warn ("IRDP: RX illegal from %s to %s while %s operates in %s\n",
-              inet_ntoa (src), 
-              ntohl(ip->ip_dst.s_addr) == INADDR_ALLRTRS_GROUP? 
-              "multicast" : inet_ntoa(ip->ip_dst),
-              ifp->name,
-              irdp->flags &  IF_BROADCAST? 
-              "broadcast" : "multicast");
+  
+  if (icmp->code != 0) 
+    {
+      zlog_warn ("IRDP: RX packet type %d from %s. Bad ICMP type code,"
+                 " silently ignored",
+                 icmp->type, inet_ntoa (src));
+      return;
+    }
 
-    zlog_warn ("IRDP: Please correct settings\n");
-    return;
-  }
+  if (! ((ntohl (ip->ip_dst.s_addr) == INADDR_BROADCAST)
+         && (irdp->flags & IF_BROADCAST))
+        ||
+        (ntohl (ip->ip_dst.s_addr) == INADDR_ALLRTRS_GROUP
+         && !(irdp->flags & IF_BROADCAST)))
+    {
+      zlog_warn ("IRDP: RX illegal from %s to %s while %s operates in %s\n",
+                 inet_ntoa (src),
+                 ntohl (ip->ip_dst.s_addr) == INADDR_ALLRTRS_GROUP ?
+                 "multicast" : inet_ntoa (ip->ip_dst),
+                 ifp->name,
+                 irdp->flags & IF_BROADCAST ? "broadcast" : "multicast");
+
+      zlog_warn ("IRDP: Please correct settings\n");
+      return;
+    }
 
   switch (icmp->type) 
     {
@@ -182,7 +191,6 @@ int irdp_recvmsg (int sock, u_char *buf, int size, int *ifindex)
 {
   struct msghdr msg;
   struct iovec iov;
-  struct cmsghdr *ptr;
   char adata[CMSG_SPACE( SOPT_SIZE_CMSG_PKTINFO_IPV4() )];
   int ret;
 
@@ -255,10 +263,12 @@ int irdp_read_raw(struct thread *r)
   }
 
   parse_irdp_packet(buf, ret, ifp);
+
   return ret;
 }
 \f
-void send_packet(struct interface *ifp, 
+void 
+send_packet(struct interface *ifp, 
            struct stream *s,
            u_int32_t dst,
            struct prefix *p,
@@ -276,10 +286,13 @@ void send_packet(struct interface *ifp,
   u_long src;
   int on;
  
-  if (! (ifp->flags & IFF_UP)) return;
+  if (!(ifp->flags & IFF_UP)) 
+    return;
 
-  if(!p) src = ntohl(p->u.prefix4.s_addr);
-  else src = 0; /* Is filled in */
+  if (!p) 
+    src = ntohl(p->u.prefix4.s_addr);
+  else 
+    src = 0; /* Is filled in */
   
   ip = (struct ip *) buf;
   ip->ip_hl = sizeof(struct ip) >> 2;
@@ -290,7 +303,7 @@ void send_packet(struct interface *ifp,
   ip->ip_ttl = ttl;
   ip->ip_src.s_addr = src;
   ip->ip_dst.s_addr = dst;
-  icmp = (struct icmphdr *) (buf + 20);
+  icmp = (struct icmphdr *) (buf + sizeof (struct ip));
 
   /* Merge IP header with icmp packet */
 
@@ -343,6 +356,8 @@ void send_packet(struct interface *ifp,
   msg->msg_control = cmsg;
   msg->msg_controllen = cmsg->cmsg_len;
  
+  sockopt_iphdrincl_swab_htosys (ip);
+  
   if (sendmsg(irdp_sock, msg, 0) < 0) {
     zlog_warn("sendto %s", strerror (errno));
   }