Create the tree entry for resource records in DNS replies, and add the

record type to the info column, before parsing the reply; add the text
for the entry, and any additional information for the info column, in
the code that handles the reply.

Don't use stuff from the resource record if you ran past the end of the
packet.

Fix some bit-scanning code.

svn path=/trunk/; revision=1736

1 files changed, 137 insertions, 152 deletions

diff --git a/packet-dns.c b/packet-dns.c
index 8825375c26..8909440339 100644
--- a/packet-dns.c
+++ b/packet-dns.c
@@ -1,7 +1,7 @@
 /* packet-dns.c
  * Routines for DNS packet disassembly
  *
- * $Id: packet-dns.c,v 1.37 2000/03/21 05:15:11 guy Exp $
+ * $Id: packet-dns.c,v 1.38 2000/03/21 06:21:37 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@zing.org>
@@ -612,23 +612,33 @@ dissect_dns_answer(const u_char *pd, int offset, int dns_data_offset,
   dptr += 2;
   cur_offset += 2;
 
+  if (fd != NULL)
+    col_append_fstr(fd, COL_INFO, " %s", type_name);
+  if (dns_tree != NULL) {
+    trr = proto_tree_add_notext(dns_tree, offset,
+				(dptr - data_start) + data_len);
+    rr_tree = add_rr_to_tree(trr, ett_dns_rr, offset, name, name_len,
+		     long_type_name, class_name, ttl, data_len);
+  }
+
   switch (type) {
+
   case T_A:
-    if (fd != NULL) {
-      col_append_fstr(fd, COL_INFO, " %s %s", type_name,
-			ip_to_str((guint8 *)dptr));
+    if (!BYTES_ARE_IN_FRAME(cur_offset, 4)) {
+      /* We ran past the end of the captured data in the packet. */
+      if (dns_tree != NULL) {
+	proto_item_set_text(trr,
+		"%s: type %s, class %s, <Address goes past end of captured data in packet>",
+		       name, type_name, class_name);
+      }
+      return 0;
     }
+    if (fd != NULL)
+      col_append_fstr(fd, COL_INFO, " %s", ip_to_str((guint8 *)dptr));
     if (dns_tree != NULL) {
-      trr = proto_tree_add_text(dns_tree, offset, (dptr - data_start) + data_len,
-		     "%s: type %s, class %s, addr %s",
+      proto_item_set_text(trr, "%s: type %s, class %s, addr %s",
 		     name, type_name, class_name,
 		     ip_to_str((guint8 *)dptr));
-      rr_tree = add_rr_to_tree(trr, ett_dns_rr, offset, name, name_len,
-		     long_type_name, class_name, ttl, data_len);
-      if (!BYTES_ARE_IN_FRAME(cur_offset, 4)) {
-	/* We ran past the end of the captured data in the packet. */
-	return 0;
-      }
       proto_tree_add_text(rr_tree, cur_offset, 4, "Addr: %s",
 		     ip_to_str((guint8 *)dptr));
     }
@@ -640,18 +650,20 @@ dissect_dns_answer(const u_char *pd, int offset, int dns_data_offset,
       int ns_name_len;
       
       ns_name_len = get_dns_name(pd, cur_offset, dns_data_offset, ns_name, sizeof(ns_name));
+      if (ns_name_len < 0) {
+	/* We ran past the end of the captured data in the packet. */
+	if (dns_tree != NULL) {
+	  proto_item_set_text(trr,
+		"%s: type %s, class %s, <Nameserver name goes past end of captured data in packet>",
+		       name, type_name, class_name);
+	}
+	return 0;
+      }
       if (fd != NULL)
-	col_append_fstr(fd, COL_INFO, " %s %s", type_name, ns_name);
+	col_append_fstr(fd, COL_INFO, " %s", ns_name);
       if (dns_tree != NULL) {
-	trr = proto_tree_add_text(dns_tree, offset, (dptr - data_start) + data_len,
-		       "%s: type %s, class %s, ns %s",
+	proto_item_set_text(trr, "%s: type %s, class %s, ns %s",
 		       name, type_name, class_name, ns_name);
-	rr_tree = add_rr_to_tree(trr, ett_dns_rr, offset, name, name_len,
-		       long_type_name, class_name, ttl, data_len);
-	if (ns_name_len < 0) {
-	  /* We ran past the end of the captured data in the packet. */
-	  return 0;
-	}
 	proto_tree_add_text(rr_tree, cur_offset, ns_name_len, "Name server: %s",
 			ns_name);
       }
@@ -664,18 +676,20 @@ dissect_dns_answer(const u_char *pd, int offset, int dns_data_offset,
       int cname_len;
       
       cname_len = get_dns_name(pd, cur_offset, dns_data_offset, cname, sizeof(cname));
+      if (cname_len < 0) {
+	/* We ran past the end of the captured data in the packet. */
+	if (dns_tree != NULL) {
+	  proto_item_set_text(trr,
+		"%s: type %s, class %s, <Primary name goes past end of captured data in packet>",
+		       name, type_name, class_name);
+	}
+	return 0;
+      }
       if (fd != NULL)
-	col_append_fstr(fd, COL_INFO, " %s %s", type_name, cname);
+	col_append_fstr(fd, COL_INFO, " %s", cname);
       if (dns_tree != NULL) {
-	trr = proto_tree_add_text(dns_tree, offset, (dptr - data_start) + data_len,
-		     "%s: type %s, class %s, cname %s",
+	proto_item_set_text(trr, "%s: type %s, class %s, cname %s",
 		     name, type_name, class_name, cname);
-	rr_tree = add_rr_to_tree(trr, ett_dns_rr, offset, name, name_len,
-		       long_type_name, class_name, ttl, data_len);
-	if (cname_len < 0) {
-	  /* We ran past the end of the captured data in the packet. */
-	  return 0;
-	}
 	proto_tree_add_text(rr_tree, cur_offset, cname_len, "Primary name: %s",
 			cname);
       }
@@ -695,28 +709,25 @@ dissect_dns_answer(const u_char *pd, int offset, int dns_data_offset,
       guint32 minimum;
 
       mname_len = get_dns_name(pd, cur_offset, dns_data_offset, mname, sizeof(mname));
-      if (mname_len >= 0)
-	rname_len = get_dns_name(pd, cur_offset + mname_len, dns_data_offset, rname, sizeof(rname));
-      else {
-      	/* We ran past the end of the captured data in the packet. */
-	rname_len = -1;
+      if (mname_len < 0) {
+	/* We ran past the end of the captured data in the packet. */
+	if (dns_tree != NULL) {
+	  proto_item_set_text(trr,
+		"%s: type %s, class %s, <mname goes past end of captured data in packet>",
+		       name, type_name, class_name);
+	}
+	return 0;
       }
       if (fd != NULL)
-	col_append_fstr(fd, COL_INFO, " %s %s", type_name, mname);
+	col_append_fstr(fd, COL_INFO, " %s", mname);
       if (dns_tree != NULL) {
-	trr = proto_tree_add_text(dns_tree, offset, (dptr - data_start) + data_len,
-		     "%s: type %s, class %s, mname %s",
+	proto_item_set_text(trr, "%s: type %s, class %s, mname %s",
 		     name, type_name, class_name, mname);
-	rr_tree = add_rr_to_tree(trr, ett_dns_rr, offset, name, name_len,
-		       long_type_name, class_name, ttl, data_len);
-	if (mname_len < 0) {
-	  /* We ran past the end of the captured data in the packet. */
-	  return 0;
-	}
 	proto_tree_add_text(rr_tree, cur_offset, mname_len, "Primary name server: %s",
 		       mname);
 	cur_offset += mname_len;
       
+	rname_len = get_dns_name(pd, cur_offset, dns_data_offset, rname, sizeof(rname));
 	if (rname_len < 0) {
 	  /* We ran past the end of the captured data in the packet. */
 	  return 0;
@@ -778,18 +789,20 @@ dissect_dns_answer(const u_char *pd, int offset, int dns_data_offset,
       int pname_len;
       
       pname_len = get_dns_name(pd, cur_offset, dns_data_offset, pname, sizeof(pname));
+      if (pname_len < 0) {
+	/* We ran past the end of the captured data in the packet. */
+	if (dns_tree != NULL) {
+	  proto_item_set_text(trr,
+		"%s: type %s, class %s, <Domain name goes past end of captured data in packet>",
+		       name, type_name, class_name);
+	}
+	return 0;
+      }
       if (fd != NULL)
-	col_append_fstr(fd, COL_INFO, " %s %s", type_name, pname);
+	col_append_fstr(fd, COL_INFO, " %s", pname);
       if (dns_tree != NULL) {
-	trr = proto_tree_add_text(dns_tree, offset, (dptr - data_start) + data_len,
-		     "%s: type %s, class %s, ptr %s",
+	proto_item_set_text(trr, "%s: type %s, class %s, ptr %s",
 		     name, type_name, class_name, pname);
-	rr_tree = add_rr_to_tree(trr, ett_dns_rr, offset, name, name_len,
-		       long_type_name, class_name, ttl, data_len);
-	if (pname_len < 0) {
-	  /* We ran past the end of the captured data in the packet. */
-	  return 0;
-	}
 	proto_tree_add_text(rr_tree, cur_offset, pname_len, "Domain name: %s",
 			pname);
       }
@@ -802,32 +815,33 @@ dissect_dns_answer(const u_char *pd, int offset, int dns_data_offset,
       int rr_len = data_len;
       guint8 protocol;
       guint8 bits;
+      int mask;
       int port_num;
       int i;
       char bitnames[128+1];
       char portnumstring[10+1];
       
-      if (fd != NULL) {
-	col_append_fstr(fd, COL_INFO, " %s %s", type_name,
-			ip_to_str((guint8 *)dptr));
+      if (!BYTES_ARE_IN_FRAME(cur_offset, 4)) {
+	/* We ran past the end of the captured data in the packet. */
+	if (dns_tree != NULL) {
+	  proto_item_set_text(trr,
+		"%s: type %s, class %s, <Address goes past end of captured data in packet>",
+		       name, type_name, class_name);
+	}
+	return 0;
       }
+      if (fd != NULL)
+	col_append_fstr(fd, COL_INFO, " %s", ip_to_str((guint8 *)dptr));
       if (dns_tree != NULL) {
-	trr = proto_tree_add_text(dns_tree, offset, (dptr - data_start) + data_len,
-		     "%s: type %s, class %s, addr %s",
+	proto_item_set_text(trr, "%s: type %s, class %s, addr %s",
 		     name, type_name, class_name,
 		     ip_to_str((guint8 *)dptr));
-	rr_tree = add_rr_to_tree(trr, ett_dns_rr, offset, name, name_len,
-		     long_type_name, class_name, ttl, data_len);
-	if (!BYTES_ARE_IN_FRAME(cur_offset, 4)) {
-	  /* We ran past the end of the captured data in the packet. */
-	  return 0;
-	}
 	proto_tree_add_text(rr_tree, cur_offset, 4, "Addr: %s",
 		     ip_to_str((guint8 *)dptr));
 	cur_offset += 4;
 	rr_len -= 4;
 
-        if (!BYTES_ARE_IN_FRAME(cur_offset, 1)) {
+	if (!BYTES_ARE_IN_FRAME(cur_offset, 1)) {
 	  /* We ran past the end of the captured data in the packet. */
 	  proto_tree_add_text(rr_tree, cur_offset, END_OF_FRAME,
 		       "<Protocol goes past end of captured data in packet>");
@@ -849,9 +863,10 @@ dissect_dns_answer(const u_char *pd, int offset, int dns_data_offset,
 	  }
 	  bits = pd[cur_offset];
 	  if (bits != 0) {
+	    mask = 1<<7;
 	    bitnames[0] = '\0';
-	    for (i = 7; i >= 0; i--) {
-	      if (bits & (1 << i)) {
+	    for (i = 0; i < 8; i++) {
+	      if (bits & mask) {
 		if (bitnames[0] != '\0')
 		  strcat(bitnames, ", ");
 		switch (protocol) {
@@ -870,6 +885,7 @@ dissect_dns_answer(const u_char *pd, int offset, int dns_data_offset,
 		  break;
 	        }
 	      }
+	      mask >>= 1;
 	      port_num++;
 	    }
 	    proto_tree_add_text(rr_tree, cur_offset, 1,
@@ -891,12 +907,6 @@ dissect_dns_answer(const u_char *pd, int offset, int dns_data_offset,
       int os_len;
 
       cpu_offset = cur_offset;
-      if (dns_tree != NULL) {
-        trr = proto_tree_add_notext(dns_tree, offset,
-				(dptr - data_start) + data_len);
-	rr_tree = add_rr_to_tree(trr, ett_dns_rr, offset, name, name_len,
-		       long_type_name, class_name, ttl, data_len);
-      }
       if (!BYTES_ARE_IN_FRAME(cpu_offset, 1)) {
 	/* We ran past the end of the captured data in the packet. */
       	if (dns_tree != NULL) {
@@ -937,7 +947,7 @@ dissect_dns_answer(const u_char *pd, int offset, int dns_data_offset,
 	return 0;
       }
       if (fd != NULL)
-	col_append_fstr(fd, COL_INFO, " %s %.*s %.*s", type_name, cpu_len,
+	col_append_fstr(fd, COL_INFO, " %.*s %.*s", cpu_len,
 	    &pd[cpu_offset + 1], os_len, &pd[os_offset + 1]);
       if (dns_tree != NULL) {
 	proto_item_set_text(trr,
@@ -959,12 +969,6 @@ dissect_dns_answer(const u_char *pd, int offset, int dns_data_offset,
       char mx_name[MAXDNAME];
       int mx_name_len;
       
-      if (dns_tree != NULL) {
-	trr = proto_tree_add_notext(dns_tree, offset,
-				(dptr - data_start) + data_len);
-	rr_tree = add_rr_to_tree(trr, ett_dns_rr, offset, name, name_len,
-		       long_type_name, class_name, ttl, data_len);
-      }
       if (!BYTES_ARE_IN_FRAME(cur_offset, 2)) {
 	/* We ran past the end of the captured data in the packet. */
       	if (dns_tree != NULL) {
@@ -986,7 +990,7 @@ dissect_dns_answer(const u_char *pd, int offset, int dns_data_offset,
 	return 0;
       }
       if (fd != NULL)
-	col_append_fstr(fd, COL_INFO, " %s %u %s", type_name, preference, mx_name);
+	col_append_fstr(fd, COL_INFO, " %u %s", preference, mx_name);
       if (dns_tree != NULL) {
 	proto_item_set_text(trr,
 		       "%s: type %s, class %s, preference %u, mx %s",
@@ -1004,40 +1008,30 @@ dissect_dns_answer(const u_char *pd, int offset, int dns_data_offset,
       int txt_offset;
       int txt_len;
 
-      if (fd != NULL)
-	col_append_fstr(fd, COL_INFO, " %s", type_name);
-      txt_offset = cur_offset;
       if (dns_tree != NULL) {
-	trr = proto_tree_add_text(dns_tree, offset, (dptr - data_start) + data_len,
-		     "%s: type %s, class %s",
-		     name, type_name, class_name);
-	rr_tree = add_rr_to_tree(trr, ett_dns_rr, offset, name, name_len,
-		       long_type_name, class_name, ttl, data_len);
-      }
-      while (rr_len != 0) {
-	if (!BYTES_ARE_IN_FRAME(txt_offset, 1)) {
-	  /* We ran past the end of the captured data in the packet. */
-	  if (dns_tree != NULL) {
+        proto_item_set_text(trr,
+		"%s: type %s, class %s", name, type_name, class_name);
+
+	txt_offset = cur_offset;
+	while (rr_len != 0) {
+	  if (!BYTES_ARE_IN_FRAME(txt_offset, 1)) {
+	    /* We ran past the end of the captured data in the packet. */
 	    proto_tree_add_text(rr_tree, txt_offset, END_OF_FRAME,
 		       "<String goes past end of captured data in packet>");
+	    return 0;
 	  }
-	  return 0;
-	}
-	txt_len = pd[txt_offset];
-	if (!BYTES_ARE_IN_FRAME(txt_offset + 1, txt_len)) {
-	  /* We ran past the end of the captured data in the packet. */
-	  if (dns_tree != NULL) {
+	  txt_len = pd[txt_offset];
+	  if (!BYTES_ARE_IN_FRAME(txt_offset + 1, txt_len)) {
+	    /* We ran past the end of the captured data in the packet. */
 	    proto_tree_add_text(rr_tree, txt_offset, END_OF_FRAME,
 		       "<String goes past end of captured data in packet>");
+	    return 0;
 	  }
-	  return 0;
-	}
-	if (dns_tree != NULL) {
 	  proto_tree_add_text(rr_tree, txt_offset, 1 + txt_len,
 	   "Text: %.*s", txt_len, &pd[txt_offset + 1]);
+	  txt_offset += 1 + txt_len;
+	  rr_len -= 1 + txt_len;
 	}
-        txt_offset += 1 + txt_len;
-        rr_len -= 1 + txt_len;
       }
     }
     break;
@@ -1049,14 +1043,9 @@ dissect_dns_answer(const u_char *pd, int offset, int dns_data_offset,
       char signer_name[MAXDNAME];
       int signer_name_len;
 
-      if (fd != NULL)
-	col_append_fstr(fd, COL_INFO, " %s", type_name);
       if (dns_tree != NULL) {
-	trr = proto_tree_add_text(dns_tree, offset, (dptr - data_start) + data_len,
-		     "%s: type %s, class %s",
-		     name, type_name, class_name);
-	rr_tree = add_rr_to_tree(trr, ett_dns_rr, offset, name, name_len,
-		       long_type_name, class_name, ttl, data_len);
+	proto_item_set_text(trr,
+		"%s: type %s, class %s", name, type_name, class_name);
 
         if (!BYTES_ARE_IN_FRAME(cur_offset, 2)) {
 	  /* We ran past the end of the captured data in the packet. */
@@ -1149,14 +1138,9 @@ dissect_dns_answer(const u_char *pd, int offset, int dns_data_offset,
       proto_item *tf;
       proto_tree *flags_tree;
 
-      if (fd != NULL)
-	col_append_fstr(fd, COL_INFO, " %s", type_name);
       if (dns_tree != NULL) {
-	trr = proto_tree_add_text(dns_tree, offset, (dptr - data_start) + data_len,
-		     "%s: type %s, class %s",
-		     name, type_name, class_name);
-	rr_tree = add_rr_to_tree(trr, ett_dns_rr, offset, name, name_len,
-		       long_type_name, class_name, ttl, data_len);
+	proto_item_set_text(trr,
+		"%s: type %s, class %s", name, type_name, class_name);
 
         if (!BYTES_ARE_IN_FRAME(cur_offset, 2)) {
 	  /* We ran past the end of the captured data in the packet. */
@@ -1231,21 +1215,23 @@ dissect_dns_answer(const u_char *pd, int offset, int dns_data_offset,
     break;
 
   case T_AAAA:
+    if (!BYTES_ARE_IN_FRAME(cur_offset, 16)) {
+      /* We ran past the end of the captured data in the packet. */
+      if (dns_tree != NULL) {
+	proto_item_set_text(trr,
+		"%s: type %s, class %s, <Address goes past end of captured data in packet>",
+		       name, type_name, class_name);
+      }
+      return 0;
+    }
     if (fd != NULL) {
-      col_append_fstr(fd, COL_INFO, " %s %s", type_name,
+      col_append_fstr(fd, COL_INFO, " %s", 
 			ip6_to_str((struct e_in6_addr *)dptr));
     }
     if (dns_tree != NULL) {
-      trr = proto_tree_add_text(dns_tree, offset, (dptr - data_start) + data_len,
-		     "%s: type %s, class %s, addr %s",
+      proto_item_set_text(trr, "%s: type %s, class %s, addr %s",
 		     name, type_name, class_name,
 		     ip6_to_str((struct e_in6_addr *)dptr));
-      rr_tree = add_rr_to_tree(trr, ett_dns_rr, offset, name, name_len,
-		     long_type_name, class_name, ttl, data_len);
-      if (!BYTES_ARE_IN_FRAME(cur_offset, 16)) {
-	/* We ran past the end of the captured data in the packet. */
-	return 0;
-      }
       proto_tree_add_text(rr_tree, cur_offset, 16, "Addr: %s",
 		     ip6_to_str((struct e_in6_addr *)dptr));
     }
@@ -1253,14 +1239,10 @@ dissect_dns_answer(const u_char *pd, int offset, int dns_data_offset,
 
   case T_LOC:
     {
-      if (fd != NULL)
-	col_append_fstr(fd, COL_INFO, " %s", type_name);
       if (dns_tree != NULL) {
-	trr = proto_tree_add_text(dns_tree, offset, (dptr - data_start) + data_len,
-		     "%s: type %s, class %s",
-		     name, type_name, class_name);
-	rr_tree = add_rr_to_tree(trr, ett_dns_rr, offset, name, name_len,
-		       long_type_name, class_name, ttl, data_len);
+	proto_item_set_text(trr,
+		"%s: type %s, class %s", name, type_name, class_name);
+
 	if (!BYTES_ARE_IN_FRAME(cur_offset, 1)) {
 	  /* We ran past the end of the captured data in the packet. */
 	  return 0;
@@ -1335,26 +1317,34 @@ dissect_dns_answer(const u_char *pd, int offset, int dns_data_offset,
 
       next_domain_name_len = get_dns_name(pd, cur_offset, dns_data_offset,
 			next_domain_name, sizeof(next_domain_name));
+      if (next_domain_name_len < 0) {
+	/* We ran past the end of the captured data in the packet. */
+	if (dns_tree != NULL) {
+	  proto_item_set_text(trr,
+		"%s: type %s, class %s, <Next domain name goes past end of captured data in packet>",
+		       name, type_name, class_name);
+	}
+	return 0;
+      }
       if (fd != NULL)
-	col_append_fstr(fd, COL_INFO, " %s %s", type_name, next_domain_name);
+	col_append_fstr(fd, COL_INFO, " %s", next_domain_name);
       if (dns_tree != NULL) {
-	trr = proto_tree_add_text(dns_tree, offset, (dptr - data_start) + data_len,
-		     "%s: type %s, class %s, next domain name %s",
+	proto_item_set_text(trr, "%s: type %s, class %s, next domain name %s",
 		     name, type_name, class_name, next_domain_name);
-	rr_tree = add_rr_to_tree(trr, ett_dns_rr, offset, name, name_len,
-		       long_type_name, class_name, ttl, data_len);
-	if (next_domain_name_len < 0) {
-	  /* We ran past the end of the captured data in the packet. */
-	  return 0;
-	}
 	proto_tree_add_text(rr_tree, cur_offset, next_domain_name_len,
 			"Next domain name: %s", next_domain_name);
 	cur_offset += next_domain_name_len;
 	rr_len -= next_domain_name_len;
 	rr_type = 0;
 	while (rr_len != 0) {
+	  if (!BYTES_ARE_IN_FRAME(cur_offset, 1)) {
+	    /* We ran past the end of the captured data in the packet. */
+	    proto_tree_add_text(rr_tree, cur_offset, END_OF_FRAME,
+		       "<Bit map goes past end of captured data in packet>");
+	    return 0;
+	  }
 	  bits = pd[cur_offset];
-	  mask = 1<<8;
+	  mask = 1<<7;
 	  for (i = 0; i < 8; i++) {
 	    if (bits & mask) {
 	      proto_tree_add_text(rr_tree, cur_offset, 1,
@@ -1375,14 +1365,9 @@ dissect_dns_answer(const u_char *pd, int offset, int dns_data_offset,
     /* TODO: parse more record types */
 
   default:
-    if (fd != NULL)
-      col_append_fstr(fd, COL_INFO, " %s", type_name);
     if (dns_tree != NULL) {
-      trr = proto_tree_add_text(dns_tree, offset, (dptr - data_start) + data_len,
-		     "%s: type %s, class %s",
-		     name, type_name, class_name);
-      rr_tree = add_rr_to_tree(trr, ett_dns_rr, offset, name, name_len,
-		       long_type_name, class_name, ttl, data_len);
+      proto_item_set_text(trr,
+		"%s: type %s, class %s", name, type_name, class_name);
       proto_tree_add_text(rr_tree, cur_offset, data_len, "Data");
     }
     break;