Dissect the payload of EAPOL Key messages.

Put in a comment noting that the payload of EAPOL Encapsulated ASF Alert
messages should perhaps be dissected as SNMP Trap messages.

Put the type of the message into the Info column.

svn path=/trunk/; revision=4789

1 files changed, 132 insertions, 34 deletions

diff --git a/packet-eapol.c b/packet-eapol.c
index 1877377c4b..74f8bd016d 100644
--- a/packet-eapol.c
+++ b/packet-eapol.c
@@ -1,7 +1,9 @@
 /* packet-eapol.c
  * Routines for EAPOL 802.1X authentication header disassembly
+ * (From IEEE Draft P802.1X/D11; is there a later draft, or a
+ * final standard?  If so, check it.)
  *
- * $Id: packet-eapol.c,v 1.7 2002/02/22 21:51:18 guy Exp $
+ * $Id: packet-eapol.c,v 1.8 2002/02/22 23:05:16 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@ethereal.com>
@@ -45,35 +47,59 @@ static int proto_eapol = -1;
 static int hf_eapol_version = -1;
 static int hf_eapol_type = -1;
 static int hf_eapol_len = -1;
+static int hf_eapol_keydes_type = -1;
+static int hf_eapol_keydes_keylen = -1;
+static int hf_eapol_keydes_replay_counter = -1;
+static int hf_eapol_keydes_key_iv = -1;
+static int hf_eapol_keydes_key_index_keytype = -1;
+static int hf_eapol_keydes_key_index_indexnum = -1;
+static int hf_eapol_keydes_key_signature = -1;
+static int hf_eapol_keydes_key = -1;
 
 static gint ett_eapol = -1;
+static gint ett_eapol_key_index = -1;
 
 static dissector_handle_t eap_handle;
 static dissector_handle_t data_handle;
 
-typedef struct _e_eapol
-{
-    guint8 eapol_ver;
-    guint8 eapol_type;
-    guint16 eapol_len;
-} e_eapol;
+#define EAPOL_HDR_LEN	4
+
+#define EAP_PACKET		0
+#define EAPOL_START		1
+#define EAPOL_LOGOFF		2
+#define EAPOL_KEY		3
+#define EAPOL_ENCAP_ASF_ALERT	4
 
 static const value_string eapol_type_vals[] = { 
-    { 0, "EAP" },
-    { 1, "Start" },
-    { 2, "Logoff" },
-    { 3, "Key" },
-    { 4, "Encapsulated ASF Alert" },
-    { 0, NULL }
+    { EAP_PACKET,            "EAP Packet" },
+    { EAPOL_START,           "Start" },
+    { EAPOL_LOGOFF,          "Logoff" },
+    { EAPOL_KEY,             "Key" },
+    { EAPOL_ENCAP_ASF_ALERT, "Encapsulated ASF Alert" },
+    { 0,                     NULL }
+};
+
+static const value_string eapol_keydes_type_vals[] = {
+	{ 1, "RC4 Descriptor" },
+	{ 0, NULL }
 };
 
+static const true_false_string keytype_tfs =
+	{ "Unicast", "Broadcast" };
+
 static void
 dissect_eapol(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 {
-  e_eapol     eapolh;
+  int         offset = 0;
+  guint8      eapol_ver;
+  guint8      eapol_type;
+  guint16     eapol_len;
   guint       len;
-  proto_tree *ti;
-  proto_tree *eapol_tree;
+  guint16     eapol_key_len;
+  guint8      key_index;
+  proto_tree *ti = NULL;
+  proto_tree *eapol_tree = NULL;
+  proto_tree *key_index_tree;
   tvbuff_t   *next_tvb;
 
   if (check_col(pinfo->cinfo, COL_PROTOCOL))
@@ -81,30 +107,77 @@ dissect_eapol(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
   if (check_col(pinfo->cinfo, COL_INFO))
     col_clear(pinfo->cinfo, COL_INFO);
 
-  tvb_memcpy(tvb, (guint8 *)&eapolh, 0, sizeof(eapolh));
-  eapolh.eapol_len = ntohs(eapolh.eapol_len);
-
-  len = sizeof(eapolh) + eapolh.eapol_len;
-
-  set_actual_length(tvb, len);
-
-  eapol_tree = NULL;
-
   if (tree) {
-    ti = proto_tree_add_item(tree, proto_eapol, tvb, 0, len, FALSE);
+    ti = proto_tree_add_item(tree, proto_eapol, tvb, 0, -1, FALSE);
     eapol_tree = proto_item_add_subtree(ti, ett_eapol);
 
-    proto_tree_add_uint(eapol_tree, hf_eapol_version, tvb, 0, 1, eapolh.eapol_ver);
-    proto_tree_add_uint(eapol_tree, hf_eapol_type,    tvb, 1, 1, eapolh.eapol_type);
-    proto_tree_add_uint(eapol_tree, hf_eapol_len,    tvb, 2, 2, eapolh.eapol_len);
+    proto_tree_add_item(eapol_tree, hf_eapol_version, tvb, offset, 1, FALSE);
   }
+  offset++;
 
-  next_tvb = tvb_new_subset(tvb, 4, -1, -1);
+  eapol_type = tvb_get_guint8(tvb, offset);
+  if (tree)
+    proto_tree_add_uint(eapol_tree, hf_eapol_type, tvb, offset, 1, eapol_type);
+  if (check_col(pinfo->cinfo, COL_INFO))
+    col_add_str(pinfo->cinfo, COL_INFO,
+		val_to_str(eapol_type, eapol_type_vals, "Unknown type (0x%02X)"));
+  offset++;
 
-  if (eapolh.eapol_type == 0)
-      call_dissector(eap_handle, next_tvb, pinfo, eapol_tree);
-  else
-      call_dissector(data_handle, next_tvb, pinfo, eapol_tree);
+  eapol_len = tvb_get_ntohs(tvb, offset);
+  len = EAPOL_HDR_LEN + eapol_len;
+  set_actual_length(tvb, len);
+  if (tree) {
+    proto_item_set_len(ti, len);
+    proto_tree_add_uint(eapol_tree, hf_eapol_len, tvb, offset, 2, eapol_len);
+  }
+  offset += 2;
+
+  switch (eapol_type) {
+
+  case EAP_PACKET:
+    next_tvb = tvb_new_subset(tvb, offset, -1, -1);
+    call_dissector(eap_handle, next_tvb, pinfo, eapol_tree);
+    break;
+
+  case EAPOL_KEY:
+    if (tree) {
+      proto_tree_add_item(eapol_tree, hf_eapol_keydes_type, tvb, offset, 1, FALSE);
+      offset += 1;
+      eapol_key_len = tvb_get_ntohs(tvb, offset);
+      proto_tree_add_uint(eapol_tree, hf_eapol_keydes_keylen, tvb, offset, 2, eapol_key_len);
+      offset += 2;
+      proto_tree_add_item(eapol_tree, hf_eapol_keydes_replay_counter, tvb,
+			  offset, 8, FALSE);
+      offset += 8;
+      proto_tree_add_item(eapol_tree, hf_eapol_keydes_key_iv, tvb,
+			  offset, 16, FALSE);
+      offset += 16;
+      key_index = tvb_get_guint8(tvb, offset);
+      ti = proto_tree_add_text(eapol_tree, tvb, offset, 1,
+			       "Key Index: %s, index %u",
+			       (key_index & 0x80) ? "unicast" : "broadcast",
+			       key_index & 0x7F);
+      key_index_tree = proto_item_add_subtree(ti, ett_eapol_key_index);
+      proto_tree_add_boolean(eapol_tree, hf_eapol_keydes_key_index_keytype,
+			     tvb, offset, 1, key_index);
+      proto_tree_add_boolean(eapol_tree, hf_eapol_keydes_key_index_indexnum,
+			     tvb, offset, 1, key_index);
+      offset += 1;
+      proto_tree_add_item(eapol_tree, hf_eapol_keydes_key_signature, tvb,
+			  offset, 16, FALSE);
+      offset += 16;
+      if (eapol_key_len != 0)
+        proto_tree_add_item(eapol_tree, hf_eapol_keydes_key, tvb, offset,
+			    eapol_key_len, FALSE);
+    }
+    break;
+
+  case EAPOL_ENCAP_ASF_ALERT:	/* XXX - is this an SNMP trap? */
+  default:
+    next_tvb = tvb_new_subset(tvb, offset, -1, -1);
+    call_dissector(data_handle, next_tvb, pinfo, eapol_tree);
+    break;
+  }
 }
 
 void
@@ -120,9 +193,34 @@ proto_register_eapol(void)
 	{ &hf_eapol_len, {
 		"Length", "eapol.len", FT_UINT16, BASE_DEC,
 		NULL, 0x0, "Length", HFILL }},
+	{ &hf_eapol_keydes_type, {
+		"Descriptor Type", "eapol.keydes.type", FT_UINT8, BASE_DEC,
+		VALS(eapol_keydes_type_vals), 0x0, "Key Descriptor Type", HFILL }},
+	{ &hf_eapol_keydes_keylen, {
+		"Key Length", "eapol.keydes.keylen", FT_UINT16, BASE_DEC,
+		NULL, 0x0, "Key Length", HFILL }},
+	{ &hf_eapol_keydes_replay_counter, {
+		"Replay Counter", "eapol.keydes.replay_counter", FT_UINT64, BASE_DEC,
+		NULL, 0x0, "Replay Counter", HFILL }},
+	{ &hf_eapol_keydes_key_iv, {
+		"Key IV", "eapol.keydes.key_iv", FT_BYTES, BASE_NONE,
+		NULL, 0x0, "Key Initialization Vector", HFILL }},
+	{ &hf_eapol_keydes_key_index_keytype, {
+		"Key Type", "eapol.keydes.index.keytype", FT_BOOLEAN, 8,
+		TFS(&keytype_tfs), 0x80, "Key Type (unicast/broadcast)", HFILL }},
+	{ &hf_eapol_keydes_key_index_indexnum, {
+		"Index Number", "eapol.keydes.index.indexnum", FT_UINT8, BASE_DEC,
+		NULL, 0x7F, "Key Index number", HFILL }},
+	{ &hf_eapol_keydes_key_signature, {
+		"Key Signature", "eapol.keydes.key_signature", FT_BYTES, BASE_NONE,
+		NULL, 0x0, "Key Signature", HFILL }},
+	{ &hf_eapol_keydes_key, {
+		"Key", "eapol.keydes.key", FT_BYTES, BASE_NONE,
+		NULL, 0x0, "Key", HFILL }},
   };
   static gint *ett[] = {
 	&ett_eapol,
+	&ett_eapol_key_index
   };
 
   proto_eapol = proto_register_protocol("802.1x Authentication", "EAPOL", "eapol");