Start removing "{OLD_}CHECK_DISPLAY_AS_DATA()" calls, and code to set

"pinfo->current_proto"; dissectors called only through dissector tables
and handles don't need to do either of those, as the dissector table and
handle code will do it for them.  (Dissectors called directly, or
dissectors that can be attached to conversations, still have to do it
themselves.)

Register the PPP Multilink Protocol, PPP Link Control Protocol, and PPP
IP Control Protocol as official protocols, and register them in PPP's
dissector table rather than having PPP handle them specially; change
"dissect_cp()" to take a protocol ID, get the protocol short name
information from it, and use the protocol ID for the top-level protocol
tree item.

Set the Protocol column in the PPP Multilink Protocol dissector, and set
the Info column before extracting anything from the frame, so that if an
exception is thrown, the Info and Protocol columns will reflect that the
packet is supposed to be a PPP Multilink Protocol frame.

Make the "First fragment" and "Last fragment" flags in the PPP Multilink
Protocol header boolean bitfields, and let "proto_tree_add_boolean()" do
all the heavy lifting when displaying them, rather than doing it by
hand.

Don't extract the sequence number in the PPP Multilink Protocol until
you're ready to put it into the tree, just in case the captured packet
includes the flags but not the sequence number.

Clean up the code to check the FCS of PPP frames - extract it with
"tvb_get_letohs()" or "tvb_get_letohl()", don't extract it byte-by-byte
and then put it together yourself.

svn path=/trunk/; revision=2926

5 files changed, 154 insertions, 137 deletions

diff --git a/packet-eth.c b/packet-eth.c
index 913ce1d03a..4fab51b777 100644
--- a/packet-eth.c
+++ b/packet-eth.c
@@ -1,7 +1,7 @@
 /* packet-eth.c
  * Routines for ethernet packet disassembly
  *
- * $Id: packet-eth.c,v 1.58 2001/01/21 20:16:01 guy Exp $
+ * $Id: packet-eth.c,v 1.59 2001/01/21 22:10:22 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@zing.org>
@@ -158,11 +158,8 @@ dissect_eth(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
   tvbuff_t		*volatile trailer_tvb;
   proto_tree		*volatile fh_tree = NULL;
 
-  CHECK_DISPLAY_AS_DATA(proto_eth, tvb, pinfo, tree);
-
   tvb_compat(tvb, &pd, (int*)&eth_offset);
 
-  pinfo->current_proto = "Ethernet";
   orig_captured_len = pinfo->captured_len;
 
   if (check_col(pinfo->fd, COL_PROTOCOL))
diff --git a/packet-fddi.c b/packet-fddi.c
index 1e707f2806..159f01bfef 100644
--- a/packet-fddi.c
+++ b/packet-fddi.c
@@ -3,7 +3,7 @@
  *
  * Laurent Deniel <deniel@worldnet.fr>
  *
- * $Id: packet-fddi.c,v 1.47 2001/01/10 09:07:35 guy Exp $
+ * $Id: packet-fddi.c,v 1.48 2001/01/21 22:10:22 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@zing.org>
@@ -234,9 +234,6 @@ dissect_fddi(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,
   u_char     src_swapped[6], dst_swapped[6];
   tvbuff_t   *next_tvb;
 
-  CHECK_DISPLAY_AS_DATA(proto_fddi, tvb, pinfo, tree);
-
-  pinfo->current_proto = "FDDI";
   if (check_col(pinfo->fd, COL_PROTOCOL))
     col_set_str(pinfo->fd, COL_PROTOCOL, "FDDI");
 
diff --git a/packet-isl.c b/packet-isl.c
index 2469f3c79f..e43e6a3e00 100644
--- a/packet-isl.c
+++ b/packet-isl.c
@@ -1,7 +1,7 @@
 /* packet-isl.c
  * Routines for Cisco ISL Ethernet header disassembly
  *
- * $Id: packet-isl.c,v 1.22 2001/01/21 20:16:01 guy Exp $
+ * $Id: packet-isl.c,v 1.23 2001/01/21 22:10:22 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@zing.org>
@@ -154,10 +154,6 @@ dissect_isl(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
   const guint8 *compat_pd;
   int compat_offset;
 
-  CHECK_DISPLAY_AS_DATA(proto_isl, tvb, pinfo, tree);
-
-  pinfo->current_proto = "ISL";
-  
   if (check_col(pinfo->fd, COL_PROTOCOL))
     col_set_str(pinfo->fd, COL_PROTOCOL, "ISL");
   if (check_col(pinfo->fd, COL_INFO))
diff --git a/packet-ppp.c b/packet-ppp.c
index bf35c822dc..df70d2675b 100644
--- a/packet-ppp.c
+++ b/packet-ppp.c
@@ -1,7 +1,7 @@
 /* packet-ppp.c
  * Routines for ppp packet disassembly
  *
- * $Id: packet-ppp.c,v 1.54 2001/01/14 08:25:14 guy Exp $
+ * $Id: packet-ppp.c,v 1.55 2001/01/21 22:10:22 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@zing.org>
@@ -48,10 +48,9 @@
 static int proto_ppp = -1;
 
 static gint ett_ppp = -1;
-static gint ett_ipcp = -1;
-static gint ett_ipcp_options = -1;
-static gint ett_ipcp_ipaddrs_opt = -1;
-static gint ett_ipcp_compressprot_opt = -1;
+
+static int proto_lcp = -1;
+
 static gint ett_lcp = -1;
 static gint ett_lcp_options = -1;
 static gint ett_lcp_mru_opt = -1;
@@ -65,7 +64,12 @@ static gint ett_lcp_callback_opt = -1;
 static gint ett_lcp_multilink_ep_disc_opt = -1;
 static gint ett_lcp_internationalization_opt = -1;
 
-static dissector_table_t subdissector_table;
+static int proto_ipcp = -1;
+
+static gint ett_ipcp = -1;
+static gint ett_ipcp_options = -1;
+static gint ett_ipcp_ipaddrs_opt = -1;
+static gint ett_ipcp_compressprot_opt = -1;
 
 static int proto_mp = -1;
 static int hf_mp_frag_first = -1;
@@ -75,6 +79,8 @@ static int hf_mp_sequence_num = -1;
 static int ett_mp = -1;
 static int ett_mp_flags = -1;
 
+static dissector_table_t subdissector_table;
+
 /* options */
 static gint ppp_fcs_decode = 0; /* 0 = No FCS, 1 = 16 bit FCS, 2 = 32 bit FCS */
 #define NO_FCS 0
@@ -637,14 +643,15 @@ fcs16(register guint16 fcs,
          guint32 len)
 {
     guint8 val;
+
     /* Check for Invalid Length */
-    if(len == 0)
-        return(0x0000);
+    if (len == 0)
+        return (0x0000);
     while (len--) {
-		val = tvb_get_guint8(tvbuff, offset++);
-		fcs = (guint16)((fcs >> 8) & 0x00ff) ^
+	val = tvb_get_guint8(tvbuff, offset++);
+	fcs = (guint16)((fcs >> 8) & 0x00ff) ^
             fcstab_16[((guint16)(fcs ^ (guint16)((val) & 0x00ff)) & 0x00ff)];
-	}
+    }
 
     return (fcs ^ 0xffff);
 }
@@ -661,9 +668,10 @@ fcs32(guint32 fcs,
          guint32 len)
 {
     guint8 val;
+
     /* Check for invalid Length */
-    if(len <= 0)
-        return(0x00000000);
+    if (len == 0)
+        return (0x00000000);
 
     while (len--) {
 	val = tvb_get_guint8(tvbuff, offset++);
@@ -1027,8 +1035,7 @@ static void dissect_ipcp_addr_opt(const ip_tcp_opt *optp, tvbuff_t *tvb,
 }
 
 static void
-dissect_cp( tvbuff_t *tvb, const char *proto_short_name,
-	const char *proto_long_name, int proto_subtree_index,
+dissect_cp( tvbuff_t *tvb, int proto_id, int proto_subtree_index,
 	const value_string *proto_vals, int options_subtree_index,
 	const ip_tcp_opt *opts, int nopts, packet_info *pinfo, proto_tree *tree ) {
   proto_item *ti;
@@ -1046,12 +1053,12 @@ dissect_cp( tvbuff_t *tvb, const char *proto_short_name,
   length = tvb_get_ntohs(tvb, 2);
 
   if(check_col(pinfo->fd, COL_INFO))
-	col_add_fstr(pinfo->fd, COL_INFO, "%sCP %s", proto_short_name,
+	col_add_fstr(pinfo->fd, COL_INFO, "%s %s",
+		proto_get_protocol_short_name(proto_id),
 		val_to_str(code, proto_vals, "Unknown"));
 
   if(tree) {
-    ti = proto_tree_add_text(tree, tvb, 0, 4, "%s Control Protocol",
-				proto_long_name);
+    ti = proto_tree_add_item(tree, proto_id, tvb, 0, length, FALSE);
     fh_tree = proto_item_add_subtree(ti, proto_subtree_index);
     proto_tree_add_text(fh_tree, tvb, 0, 1, "Code: %s (0x%02x)",
       val_to_str(code, proto_vals, "Unknown"), code);
@@ -1173,31 +1180,27 @@ dissect_ppp_stuff( tvbuff_t *tvb, packet_info *pinfo,
 
   /* do lookup with the subdissector table */
   if (dissector_try_port(subdissector_table, ppp_prot, next_tvb, pinfo, tree))
-      return TRUE;
-
-  /* XXX - make "dissect_lcp()" and "dissect_ipcp()", have them just
-     call "dissect_cp()", and register them as well?
-
-     We can do that for "dissect_mp()", too. */
-  switch (ppp_prot) {
-    case PPP_MP:
-      dissect_mp(next_tvb, pinfo, tree);
-      return TRUE;
-    case PPP_LCP:
-      dissect_cp(next_tvb, "L", "Link", ett_lcp, lcp_vals, ett_lcp_options,
-		lcp_opts, N_LCP_OPTS, pinfo, tree);
-      return TRUE;
-    case PPP_IPCP:
-      dissect_cp(next_tvb, "IP", "IP", ett_ipcp, cp_vals, ett_ipcp_options,
-		ipcp_opts, N_IPCP_OPTS, pinfo, tree);
-      return TRUE;
-    default:
-      if (check_col(pinfo->fd, COL_INFO))
-        col_add_fstr(pinfo->fd, COL_INFO, "PPP %s (0x%04x)",
+    return TRUE;
+
+  if (check_col(pinfo->fd, COL_INFO))
+    col_add_fstr(pinfo->fd, COL_INFO, "PPP %s (0x%04x)",
 		val_to_str(ppp_prot, ppp_vals, "Unknown"), ppp_prot);
-      dissect_data(next_tvb, 0, pinfo, tree);
-      return FALSE;
-  }
+  dissect_data(next_tvb, 0, pinfo, tree);
+  return FALSE;
+}
+
+static void
+dissect_lcp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+  dissect_cp(tvb, proto_lcp, ett_lcp, lcp_vals, ett_lcp_options,
+	     lcp_opts, N_LCP_OPTS, pinfo, tree);
+}
+
+static void
+dissect_ipcp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+  dissect_cp(tvb, proto_ipcp, ett_ipcp, cp_vals, ett_ipcp_options,
+	     ipcp_opts, N_IPCP_OPTS, pinfo, tree);
 }
 
 #define MP_FRAG_MASK     0xC0
@@ -1206,6 +1209,11 @@ dissect_ppp_stuff( tvbuff_t *tvb, packet_info *pinfo,
 #define MP_FRAG_LAST     0x40
 #define MP_FRAG_RESERVED 0x3f
 
+static const true_false_string frag_truth = {
+  "Yes",
+  "No"
+};
+
 /* According to RFC 1717, the length the MP header isn't indicated anywhere
    in the header itself.  It starts out at four bytes and can be
    negotiated down to two using LCP.  We currently assume that all
@@ -1217,20 +1225,16 @@ dissect_mp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
   proto_tree *mp_tree, *hdr_tree, *fh_tree = NULL;
   proto_item *ti;
   guint8      flags;
-  guint32     seq;
-  gchar       *flag_str;
-  int         first, last;
-  tvbuff_t	*next_tvb;
-
-  CHECK_DISPLAY_AS_DATA(proto_mp, tvb, pinfo, tree);
+  gchar      *flag_str;
+  tvbuff_t   *next_tvb;
 
-  flags = tvb_get_guint8(tvb, 0);
-  first = flags && MP_FRAG_FIRST;
-  last  = flags && MP_FRAG_LAST;
-  seq   = tvb_get_ntoh24(tvb, 1);
+  if (check_col(pinfo->fd, COL_PROTOCOL))
+    col_set_str(pinfo->fd, COL_PROTOCOL, "PPP MP");
 
   if (check_col(pinfo->fd, COL_INFO))
-    col_add_fstr(pinfo->fd, COL_INFO, "PPP Multilink");
+    col_set_str(pinfo->fd, COL_INFO, "PPP Multilink");
+
+  flags = tvb_get_guint8(tvb, 0);
 
   if (tree) {
     switch (flags) {
@@ -1252,26 +1256,22 @@ dissect_mp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
     ti = proto_tree_add_text(mp_tree, tvb, 0, 1, "Fragment: 0x%2X (%s)",
       flags, flag_str);
     hdr_tree = proto_item_add_subtree(ti, ett_mp_flags);
-    proto_tree_add_boolean_format(hdr_tree, hf_mp_frag_first, tvb, 0, 1, first,
-      "%s", decode_boolean_bitfield(flags, MP_FRAG_FIRST, sizeof(flags) * 8,
-        "first", "not first"));
-    proto_tree_add_boolean_format(hdr_tree, hf_mp_frag_last, tvb, 0, 1, last,
-      "%s", decode_boolean_bitfield(flags, MP_FRAG_LAST, sizeof(flags) * 8,
-        "last", "not last"));
+    proto_tree_add_boolean(hdr_tree, hf_mp_frag_first, tvb, 0, 1, flags);
+    proto_tree_add_boolean(hdr_tree, hf_mp_frag_last, tvb, 0, 1, flags),
     proto_tree_add_text(hdr_tree, tvb, 0, 1, "%s",
       decode_boolean_bitfield(flags, MP_FRAG_RESERVED, sizeof(flags) * 8,
         "reserved", "reserved"));
-    proto_tree_add_uint(mp_tree, hf_mp_sequence_num, tvb,  1, 3, seq);
- }
+    proto_tree_add_item(mp_tree, hf_mp_sequence_num, tvb,  1, 3, FALSE);
+  }
 
   next_tvb = tvb_new_subset(tvb, 4, -1, -1);
 
   if (tvb_length(next_tvb) > 0) {
-	  if (tree) {
-	    ti = proto_tree_add_item(tree, proto_ppp, next_tvb, 0, 1, FALSE);
-	    fh_tree = proto_item_add_subtree(ti, ett_ppp);
-	  }
-	  dissect_ppp_stuff(next_tvb, pinfo, tree, fh_tree);
+    if (tree) {
+      ti = proto_tree_add_item(tree, proto_ppp, next_tvb, 0, 1, FALSE);
+      fh_tree = proto_item_add_subtree(ti, ett_ppp);
+    }
+    dissect_ppp_stuff(next_tvb, pinfo, tree, fh_tree);
   }
 }
 
@@ -1298,12 +1298,10 @@ dissect_ppp( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree ) {
   int        proto_offset;
   tvbuff_t   *next_tvb;
   guint8     byte0;
+  int        rx_fcs_offset;
   guint32    rx_fcs_exp;
   guint32    rx_fcs_got;
 
-  CHECK_DISPLAY_AS_DATA(proto_ppp, tvb, pinfo, tree);
-
-  pinfo->current_proto = "PPP";
   byte0 = tvb_get_guint8(tvb, 0);
 
   if (byte0 == 0xff) {
@@ -1356,33 +1354,26 @@ dissect_ppp( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree ) {
   }
 
   /* Calculate the FCS check */
+  /* XXX - deal with packets cut off by the snapshot length */
   if (ppp_fcs_decode == FCS_16) {
-    rx_fcs_got = 0;
-    rx_fcs_exp = fcs16(0xFFFF, tvb, 0, tvb_length(tvb) - 2);
-    rx_fcs_got = tvb_get_guint8(tvb, tvb_length(tvb) - 2) |
-        (tvb_get_guint8(tvb, tvb_length(tvb) - 1) << 8);
-  	if (rx_fcs_got != rx_fcs_exp) {
-      proto_tree_add_text(fh_tree, tvb, tvb_length(tvb) - 2, 2, "FCS 16: %04x (incorrect, should be %04x)", rx_fcs_got, rx_fcs_exp);
-  	}
-  	else {
-      proto_tree_add_text(fh_tree, tvb, tvb_length(tvb) - 2, 2, "FCS 16: %04x (correct)", rx_fcs_got);
-  	}
-  }
-  else if(ppp_fcs_decode == FCS_32) {
-    rx_fcs_got = 0;
-    rx_fcs_exp = fcs32(0xFFFFFFFF, tvb, 0, tvb_length(tvb) - 4);
-    rx_fcs_got = tvb_get_guint8(tvb, tvb_length(tvb) - 4) |
-        (tvb_get_guint8(tvb, tvb_length(tvb) - 3) << 8) |
-        (tvb_get_guint8(tvb, tvb_length(tvb) - 2) << 16) | 
-        (tvb_get_guint8(tvb, tvb_length(tvb) - 1) << 24);
-  	if (rx_fcs_got != rx_fcs_exp) {
-      proto_tree_add_text(fh_tree, tvb, tvb_length(tvb) - 4, 4, "FCS 32: %08x (incorrect, should be %08x) ", rx_fcs_got, rx_fcs_exp);
-  	}
-  	else {
-      proto_tree_add_text(fh_tree, tvb, tvb_length(tvb) - 4, 4, "FCS 32: %08x (correct)", rx_fcs_got);
-  	}
+    rx_fcs_offset = tvb_length(tvb) - 2;
+    rx_fcs_exp = fcs16(0xFFFF, tvb, 0, rx_fcs_offset);
+    rx_fcs_got = tvb_get_letohs(tvb, rx_fcs_offset);
+    if (rx_fcs_got != rx_fcs_exp) {
+      proto_tree_add_text(fh_tree, tvb, rx_fcs_offset, 2, "FCS 16: %04x (incorrect, should be %04x)", rx_fcs_got, rx_fcs_exp);
+    } else {
+      proto_tree_add_text(fh_tree, tvb, rx_fcs_offset, 2, "FCS 16: %04x (correct)", rx_fcs_got);
+    }
+  } else if (ppp_fcs_decode == FCS_32) {
+    rx_fcs_offset = tvb_length(tvb) - 4;
+    rx_fcs_exp = fcs32(0xFFFFFFFF, tvb, 0, rx_fcs_offset);
+    rx_fcs_got = tvb_get_letohl(tvb, rx_fcs_offset);
+    if (rx_fcs_got != rx_fcs_exp) {
+      proto_tree_add_text(fh_tree, tvb, rx_fcs_offset, 4, "FCS 32: %08x (incorrect, should be %08x) ", rx_fcs_got, rx_fcs_exp);
+    } else {
+      proto_tree_add_text(fh_tree, tvb, rx_fcs_offset, 4, "FCS 32: %08x (correct)", rx_fcs_got);
+    }
   }
-
 }
 
 void
@@ -1394,22 +1385,6 @@ proto_register_ppp(void)
         };*/
 	static gint *ett[] = {
 		&ett_ppp,
-		&ett_ipcp,
-		&ett_ipcp_options,
-		&ett_ipcp_ipaddrs_opt,
-		&ett_ipcp_compressprot_opt,
-		&ett_lcp,
-		&ett_lcp_options,
-		&ett_lcp_mru_opt,
-		&ett_lcp_async_map_opt,
-		&ett_lcp_authprot_opt,
-		&ett_lcp_qualprot_opt,
-		&ett_lcp_magicnum_opt,
-		&ett_lcp_fcs_alternatives_opt,
-		&ett_lcp_numbered_mode_opt,
-		&ett_lcp_callback_opt,
-		&ett_lcp_multilink_ep_disc_opt,
-		&ett_lcp_internationalization_opt,
 	};
 
 	static enum_val_t ppp_options[] = {
@@ -1444,16 +1419,25 @@ proto_register_ppp(void)
 }
 
 void
+proto_reg_handoff_ppp(void)
+{
+  dissector_add("wtap_encap", WTAP_ENCAP_PPP, dissect_ppp, proto_ppp);
+  dissector_add("wtap_encap", WTAP_ENCAP_PPP_WITH_PHDR, dissect_ppp, proto_ppp);
+  dissector_add("fr.ietf", NLPID_PPP, dissect_ppp, proto_ppp);
+  dissector_add("gre.proto", ETHERTYPE_PPP, dissect_ppp, proto_ppp);
+}
+
+void
 proto_register_mp(void)
 {
   static hf_register_info hf[] = {
     { &hf_mp_frag_first,
-    { "First fragment",		"mp.first",	FT_BOOLEAN, BASE_NONE, NULL, 0x0,
-    	"" }},
+    { "First fragment",		"mp.first",	FT_BOOLEAN, 8,
+        TFS(&frag_truth), MP_FRAG_FIRST, "" }},
 
     { &hf_mp_frag_last,
-    { "Last fragment",		"mp.last",	FT_BOOLEAN, BASE_NONE, NULL, 0x0,
-    	"" }},
+    { "Last fragment",		"mp.last",	FT_BOOLEAN, 8,
+        TFS(&frag_truth), MP_FRAG_LAST, "" }},
 
     { &hf_mp_sequence_num,
     { "Sequence number",	"mp.seq",	FT_UINT24, BASE_DEC, NULL, 0x0,
@@ -1470,10 +1454,57 @@ proto_register_mp(void)
 }
 
 void
-proto_reg_handoff_ppp(void)
+proto_reg_handoff_mp(void)
 {
-  dissector_add("wtap_encap", WTAP_ENCAP_PPP, dissect_ppp, proto_ppp);
-  dissector_add("wtap_encap", WTAP_ENCAP_PPP_WITH_PHDR, dissect_ppp, proto_ppp);
-  dissector_add("fr.ietf", NLPID_PPP, dissect_ppp, proto_ppp);
-  dissector_add("gre.proto", ETHERTYPE_PPP, dissect_ppp, proto_ppp);
+  dissector_add("ppp.protocol", PPP_MP, dissect_mp, proto_mp);
+}
+
+void
+proto_register_lcp(void)
+{
+  static gint *ett[] = {
+    &ett_lcp,
+    &ett_lcp_options,
+    &ett_lcp_mru_opt,
+    &ett_lcp_async_map_opt,
+    &ett_lcp_authprot_opt,
+    &ett_lcp_qualprot_opt,
+    &ett_lcp_magicnum_opt,
+    &ett_lcp_fcs_alternatives_opt,
+    &ett_lcp_numbered_mode_opt,
+    &ett_lcp_callback_opt,
+    &ett_lcp_multilink_ep_disc_opt,
+    &ett_lcp_internationalization_opt,
+  };
+
+  proto_lcp = proto_register_protocol("PPP Link Control Protocol", "PPP LCP",
+				      "lcp");
+  proto_register_subtree_array(ett, array_length(ett));
+}
+
+void
+proto_reg_handoff_lcp(void)
+{
+  dissector_add("ppp.protocol", PPP_LCP, dissect_lcp, proto_lcp);
+}
+
+void
+proto_register_ipcp(void)
+{
+  static gint *ett[] = {
+    &ett_ipcp,
+    &ett_ipcp_options,
+    &ett_ipcp_ipaddrs_opt,
+    &ett_ipcp_compressprot_opt,
+  };
+
+  proto_ipcp = proto_register_protocol("PPP IP Control Protocol", "PPP IPCP",
+				      "ipcp");
+  proto_register_subtree_array(ett, array_length(ett));
+}
+
+void
+proto_reg_handoff_ipcp(void)
+{
+  dissector_add("ppp.protocol", PPP_IPCP, dissect_ipcp, proto_ipcp);
 }
diff --git a/packet-tr.c b/packet-tr.c
index d3e1592607..c9fa411a9e 100644
--- a/packet-tr.c
+++ b/packet-tr.c
@@ -2,7 +2,7 @@
  * Routines for Token-Ring packet disassembly
  * Gilbert Ramirez <gram@xiexie.org>
  *
- * $Id: packet-tr.c,v 1.57 2001/01/21 20:16:01 guy Exp $
+ * $Id: packet-tr.c,v 1.58 2001/01/21 22:10:22 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@zing.org>
@@ -325,10 +325,6 @@ dissect_tr(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 	/* Token-Ring Strings */
 	char *fc[] = { "MAC", "LLC", "Reserved", "Unknown" };
 
-	CHECK_DISPLAY_AS_DATA(proto_tr, tvb, pinfo, tree);
-
-	pinfo->current_proto = "Token-Ring";
-
 	if (check_col(pinfo->fd, COL_PROTOCOL))
 		col_set_str(pinfo->fd, COL_PROTOCOL, "TR");