Allow user-specified symmetric crypto algorithms.

[tripe] / ethereal / packet-tripe.c

diff --git a/ethereal/packet-tripe.c b/ethereal/packet-tripe.c
index 4b4e0aceb6e60c67e3561be50a7300a805f01d48..afeb1bcc3435e0dea8960942169ef4e783d56e5a 100644 (file)
--- a/ethereal/packet-tripe.c
+++ b/ethereal/packet-tripe.c
@@ -1,6 +1,6 @@
 /* -*-c-*-
  *
- * $Id: packet-tripe.c,v 1.3 2004/04/08 01:36:17 mdw Exp $
+ * $Id: packet-tripe.c,v 1.4 2004/04/18 18:08:11 mdw Exp $
  *
  * TrIPE protocol dissector for Ethereal
  *
@@ -39,6 +39,7 @@
 #include <glib.h>
 #include <gmodule.h>
 #include <epan/packet.h>
+#include <prefs.h>
 
 #ifdef ETHEREAL_BUGGERED
 #  define plugin_address_table_t void
@@ -53,6 +54,8 @@
 
 static int proto_tripe = -1;
 
+static guint hashsz = 20, tagsz = 10, ivsz = 8;
+
 typedef struct hfmp {
   int hf, hf_len, hf_val, tt;
 } hfmp;
@@ -65,8 +68,8 @@ static int hf_tripe_packet_type = -1;
 static int hf_tripe_ct = -1;
 static int hf_tripe_ct_seq = -1;
 static int hf_tripe_ct_iv = -1;
-static int hf_tripe_ct_cbc = -1;
-static int hf_tripe_ct_mac = -1;
+static int hf_tripe_ct_ct = -1;
+static int hf_tripe_ct_tag = -1;
 static int hf_tripe_kx_type = -1;
 static hfge hf_tripe_kx_mychal = { -1, -1, -1, -1, -1, -1, -1, -1 };
 static int hf_tripe_kx_mycookie = -1;
@@ -81,10 +84,12 @@ G_MODULE_EXPORT const gchar version[] = VERSION;
 
 /*----- Main code ---------------------------------------------------------*/
 
+static void prefcb(void) { }
+
 static gint gethash(proto_tree *tt, int hf, tvbuff_t *b, gint off)
 {
-  proto_tree_add_item(tt, hf, b, off, 20, FALSE);
-  return (off + 20); 
+  proto_tree_add_item(tt, hf, b, off, hashsz, FALSE);
+  return (off + hashsz); 
 }
 
 static gint getmp(proto_tree *tt, const hfmp *hf, tvbuff_t *b, gint off)
@@ -246,17 +251,21 @@ static void dissect_tripe(tvbuff_t *b, packet_info *p, proto_tree *t)
     goto done;
   ct:
     ti = proto_tree_add_item(tt, hf_tripe_ct, b, off, -1, FALSE);
-    seq = tvb_get_ntohl(b, off + 10);
+    seq = tvb_get_ntohl(b, off + tagsz);
     proto_item_set_text(ti, "Encrypted ciphertext (sequence number %lu)",
                        (unsigned long)seq);
     tt = proto_item_add_subtree(ti, tt_tripe_ct);
-    proto_tree_add_item(tt, hf_tripe_ct_mac, b, off, 10, FALSE);
-    off += 10;
+    if (tagsz) {
+      proto_tree_add_item(tt, hf_tripe_ct_tag, b, off, tagsz, FALSE);
+      off += tagsz;
+    }
     proto_tree_add_item(tt, hf_tripe_ct_seq, b, off, 4, FALSE);
     off += 4;
-    proto_tree_add_item(tt, hf_tripe_ct_iv, b, off, 8, FALSE);
-    off += 8;
-    proto_tree_add_item(ti, hf_tripe_ct_cbc, b, off, -1, FALSE);
+    if (ivsz) {
+      proto_tree_add_item(tt, hf_tripe_ct_iv, b, off, ivsz, FALSE);
+      off += ivsz;
+    }
+    proto_tree_add_item(ti, hf_tripe_ct_ct, b, off, -1, FALSE);
     goto done;
   done:;
   }  
@@ -264,6 +273,8 @@ static void dissect_tripe(tvbuff_t *b, packet_info *p, proto_tree *t)
 
 void proto_register_tripe(void)
 {
+  module_t *mod;
+
   static value_string vs_kxtype[] = {
     { KX_PRECHAL,      "KX_PRECHAL (prechallenge)" },
     { KX_COOKIE,       "KX_COOKIE (cookie)" },
@@ -299,15 +310,15 @@ void proto_register_tripe(void)
       FT_BYTES, BASE_NONE, 0, 0,
       "This is the initialization vector used for the actual encryption."
     },
-    &hf_tripe_ct_cbc, {
-      "CBC-encrypted data", "tripe.ct.cbc",
+    &hf_tripe_ct_ct, {
+      "Actual encrypted data", "tripe.ct.ct",
       FT_BYTES, BASE_NONE, 0, 0,
-      "This is the CBC-encrypted message.  Reading it ought to be hard."
+      "This is the encrypted message.  Reading it ought to be hard."
     },
-    &hf_tripe_ct_mac, {
-      "Message authentication code", "tripe.ct.mac",
+    &hf_tripe_ct_tag, {
+      "Message authentication code", "tripe.ct.tag",
       FT_BYTES, BASE_NONE, 0, 0,
-      "This is the message authentication code for the ciphertext."
+      "This is the message authentication code tag for the ciphertext."
     },
     &hf_tripe_kx_type, {
       "Key-exchange message type", "tripe.kx.type",
@@ -392,6 +403,17 @@ void proto_register_tripe(void)
   proto_tripe = proto_register_protocol("TrIPE", "TrIPE", "tripe");
   proto_register_field_array(proto_tripe, hfs, array_length(hfs));
   proto_register_subtree_array(tts, array_length(tts));
+
+  mod = prefs_register_protocol(proto_tripe, prefcb);
+  prefs_register_uint_preference(mod, "hashsz", "Hash length",
+                                "hash function output length (in octets)",
+                                10, &hashsz);
+  prefs_register_uint_preference(mod, "tagsz", "MAC tag length",
+                                "MAC tag length (in octets)", 10, &tagsz);
+  prefs_register_uint_preference(mod, "ivsz", "IV length",
+                                "block cipher initialization vector length"
+                                " (in octets)",
+                                10, &ivsz);
 }
 
 void proto_reg_handoff_tripe(void)