Rewrite dissectors to use Libgcrypt functions.

As discussed on the mailinglist, rewriting dissectors to use Libgcrypt
functions as Libgcrypt will be mandatory after change 20030.
Removal of following functions:
- crypt_md4
- crypt_rc4*
- aes_cmac_encrypt_*
- md5_*
- sha1_*
- sha256_*

Further candidates:
- aes_*
- rijndael_*
- ...

Added functions:
- ws_hmac_buffer

Added const macros:
- HASH_MD5_LENGTH
- HASH_SHA1_LENGTH

Changes on epan/crypt/* verified with captures from
https://wiki.wireshark.org/HowToDecrypt802.11
Changes on packet-snmp.c and packet-radius.c verified with captures from
https://wiki.wireshark.org/SampleCapture
Changes on packet-tacacs.c verified with capture from
http://ccie-in-3-months.blogspot.nl/2009/04/decoding-login-credentials-regardless.html

Change-Id: Iea6ba2bf207cf0f1bf2117068fb1abcfeaafaa46
Link: https://www.wireshark.org/lists/wireshark-dev/201702/msg00011.html
Reviewed-on: https://code.wireshark.org/review/20095
Petri-Dish: Peter Wu <peter@lekensteyn.nl>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Peter Wu <peter@lekensteyn.nl>

1 files changed, 9 insertions, 17 deletions

diff --git a/epan/dissectors/packet-tacacs.c b/epan/dissectors/packet-tacacs.c
index ec90469db7..b1dc48be6a 100644
--- a/epan/dissectors/packet-tacacs.c
+++ b/epan/dissectors/packet-tacacs.c
@@ -38,7 +38,7 @@
 #include <epan/prefs.h>
 #include <epan/expert.h>
 #include <epan/addr_resolv.h>
-#include <wsutil/md5.h>
+#include <wsutil/wsgcrypt.h>
 #include <wsutil/ws_printf.h> /* ws_debug_printf */
 
 #include "packet-tacacs.h"
@@ -1280,23 +1280,19 @@ proto_reg_handoff_tacplus(void)
 	dissector_add_uint_with_preference("tcp.port", TCP_PORT_TACACS, tacplus_handle);
 }
 
-
-#define MD5_LEN 16
-
 static void
 md5_xor( guint8 *data, const char *key, int data_len, guint8 *session_id, guint8 version, guint8 seq_no )
 {
 	int i,j;
 	size_t md5_len;
-	md5_byte_t *md5_buff;
-	md5_byte_t hash[MD5_LEN];				/* the md5 hash */
-	md5_byte_t *mdp;
-	md5_state_t mdcontext;
+	guint8 *md5_buff;
+	guint8 hash[HASH_MD5_LENGTH];				/* the md5 hash */
+	guint8 *mdp;
 
 	md5_len = 4 /* sizeof(session_id) */ + strlen(key)
 			+ sizeof(version) + sizeof(seq_no);
 
-	md5_buff = (md5_byte_t*)wmem_alloc(wmem_packet_scope(), md5_len+MD5_LEN);
+	md5_buff = (guint8*)wmem_alloc(wmem_packet_scope(), md5_len + HASH_MD5_LENGTH);
 
 
 	mdp = md5_buff;
@@ -1308,10 +1304,8 @@ md5_xor( guint8 *data, const char *key, int data_len, guint8 *session_id, guint8
 	*mdp++ = seq_no;
 
 
-	md5_init(&mdcontext);
-	md5_append(&mdcontext, md5_buff, md5_len);
-	md5_finish(&mdcontext,hash);
-	md5_len += MD5_LEN;
+	gcry_md_hash_buffer(GCRY_MD_MD5, hash, md5_buff, md5_len);
+	md5_len += HASH_MD5_LENGTH;
 	for (i = 0; i < data_len; i += 16) {
 
 		for (j = 0; j < 16; j++) {
@@ -1321,10 +1315,8 @@ md5_xor( guint8 *data, const char *key, int data_len, guint8 *session_id, guint8
 			}
 			data[i + j] ^= hash[j];
 		}
-		memcpy(mdp, hash, MD5_LEN);
-		md5_init(&mdcontext);
-		md5_append(&mdcontext, md5_buff, md5_len);
-		md5_finish(&mdcontext,hash);
+		memcpy(mdp, hash, HASH_MD5_LENGTH);
+		gcry_md_hash_buffer(GCRY_MD_MD5, hash, md5_buff, md5_len);
 	}
 }