- Fixed twofish algorithm naming so it actually works.

- Added support for aes256, twofish256 and sha1-96
- Fixed some debugging statements

--HG--
extra : convert_revision : 598835dadaddb1e95d4ac99f8a1be4ba51639000

common-algo.c

@@ -32,6 +32,10 @@
 /* Mappings for ciphers, parameters are
    {&cipher_desc, keysize, blocksize} */
 
+#ifdef DROPBEAR_AES256_CBC
+static const struct dropbear_cipher dropbear_aes256 = 
+	{&aes_desc, 32, 16};
+#endif
 #ifdef DROPBEAR_AES128_CBC
 static const struct dropbear_cipher dropbear_aes128 = 
 	{&aes_desc, 16, 16};
@@ -40,6 +44,10 @@ static const struct dropbear_cipher dropbear_aes128 =
 static const struct dropbear_cipher dropbear_blowfish = 
 	{&blowfish_desc, 16, 8};
 #endif
+#ifdef DROPBEAR_TWOFISH256_CBC
+static const struct dropbear_cipher dropbear_twofish256 = 
+	{&twofish_desc, 32, 16};
+#endif
 #ifdef DROPBEAR_TWOFISH128_CBC
 static const struct dropbear_cipher dropbear_twofish128 = 
 	{&twofish_desc, 16, 16};
@@ -60,6 +68,10 @@ const struct dropbear_cipher dropbear_nocipher =
 static const struct dropbear_hash dropbear_sha1 = 
 	{&sha1_desc, 20, 20};
 #endif
+#ifdef DROPBEAR_SHA1_96_HMAC
+static const struct dropbear_hash dropbear_sha1_96 = 
+	{&sha1_desc, 20, 12};
+#endif
 #ifdef DROPBEAR_MD5_HMAC
 static const struct dropbear_hash dropbear_md5 = 
 	{&md5_desc, 16, 16};
@@ -75,19 +87,28 @@ algo_type sshciphers[] = {
 #ifdef DROPBEAR_AES128_CBC
 	{"aes128-cbc", 0, (void*)&dropbear_aes128, 1},
 #endif
+#ifdef DROPBEAR_3DES_CBC
+	{"3des-cbc", 0, (void*)&dropbear_3des, 1},
+#endif
+#ifdef DROPBEAR_AES256_CBC
+	{"aes256-cbc", 0, (void*)&dropbear_aes256, 1},
+#endif
 #ifdef DROPBEAR_BLOWFISH_CBC
 	{"blowfish-cbc", 0, (void*)&dropbear_blowfish, 1},
 #endif
-#ifdef DROPBEAR_TWOFISH128_CBC
+#ifdef DROPBEAR_TWOFISH256_CBC
-	{"twofish-cbc", 0, (void*)&dropbear_twofish128, 1},
+	{"twofish256-cbc", 0, (void*)&dropbear_twofish256, 1},
 #endif
-#ifdef DROPBEAR_3DES_CBC
+#ifdef DROPBEAR_TWOFISH128_CBC
-	{"3des-cbc", 0, (void*)&dropbear_3des, 1},
+	{"twofish128-cbc", 0, (void*)&dropbear_twofish128, 1},
 #endif
 	{NULL, 0, NULL, 0}
 };
 
 algo_type sshhashes[] = {
+#ifdef DROPBEAR_SHA1_96_HMAC
+	{"hmac-sha1-96", 0, (void*)&dropbear_sha1_96, 1},
+#endif
 #ifdef DROPBEAR_SHA1_HMAC
 	{"hmac-sha1", 0, (void*)&dropbear_sha1, 1},
 #endif

common-kex.c

@@ -622,7 +622,7 @@ static void read_kex_algos() {
 		erralgo = "enc c->s";
 		goto error;
 	}
-	TRACE(("c2s is  %s", c2s_cipher_algo->name))
+	TRACE(("enc c2s is  %s", c2s_cipher_algo->name))
 
 	/* encryption_algorithms_server_to_client */
 	s2c_cipher_algo = ses.buf_match_algo(ses.payload, sshciphers, &goodguess);
@@ -630,7 +630,7 @@ static void read_kex_algos() {
 		erralgo = "enc s->c";
 		goto error;
 	}
-	TRACE(("s2c is  %s", s2c_cipher_algo->name))
+	TRACE(("enc s2c is  %s", s2c_cipher_algo->name))
 
 	/* mac_algorithms_client_to_server */
 	c2s_hash_algo = ses.buf_match_algo(ses.payload, sshhashes, &goodguess);
@@ -638,6 +638,7 @@ static void read_kex_algos() {
 		erralgo = "mac c->s";
 		goto error;
 	}
+	TRACE(("hash c2s is  %s", c2s_hash_algo->name))
 
 	/* mac_algorithms_server_to_client */
 	s2c_hash_algo = ses.buf_match_algo(ses.payload, sshhashes, &goodguess);
@@ -645,6 +646,7 @@ static void read_kex_algos() {
 		erralgo = "mac s->c";
 		goto error;
 	}
+	TRACE(("hash s2c is  %s", s2c_hash_algo->name))
 
 	/* compression_algorithms_client_to_server */
 	c2s_comp_algo = ses.buf_match_algo(ses.payload, sshcompress, &goodguess);
@@ -652,6 +654,7 @@ static void read_kex_algos() {
 		erralgo = "comp c->s";
 		goto error;
 	}
+	TRACE(("hash c2s is  %s", c2s_comp_algo->name))
 
 	/* compression_algorithms_server_to_client */
 	s2c_comp_algo = ses.buf_match_algo(ses.payload, sshcompress, &goodguess);
@@ -659,6 +662,7 @@ static void read_kex_algos() {
 		erralgo = "comp s->c";
 		goto error;
 	}
+	TRACE(("hash s2c is  %s", s2c_comp_algo->name))
 
 	/* languages_client_to_server */
 	buf_eatstring(ses.payload);
@@ -701,13 +705,6 @@ static void read_kex_algos() {
 		ses.newkeys->trans_algo_comp = s2c_comp_algo->val;
 	}
 
-	TRACE(("enc algo recv %s", algo->name))
-	TRACE(("enc algo trans %s", algo->name))
-	TRACE(("mac algo recv %s", algo->name))
-	TRACE(("mac algo trans %s", algo->name))
-	TRACE(("comp algo recv %s", algo->name))
-	TRACE(("comp algo trans %s", algo->name))
-
 	/* reserved for future extensions */
 	buf_getint(ses.payload);
 	return;

options.h

@@ -62,25 +62,30 @@ etc) slower (perhaps by 50%). Recommended for most small systems. */
 #define ENABLE_AGENTFWD
 
 /* Encryption - at least one required.
- * RFC Draft requires 3DES, and recommends Blowfish, AES128 & Twofish128 */
+ * RFC Draft requires 3DES and recommends AES128 for interoperability.
+ * Including multiple keysize variants the same cipher 
+ * (eg AES256 as well as AES128) will result in a minimal size increase.*/
 #define DROPBEAR_AES128_CBC
-#define DROPBEAR_BLOWFISH_CBC
-#define DROPBEAR_TWOFISH128_CBC
 #define DROPBEAR_3DES_CBC
+#define DROPBEAR_AES256_CBC
+#define DROPBEAR_BLOWFISH_CBC
+#define DROPBEAR_TWOFISH256_CBC
+#define DROPBEAR_TWOFISH128_CBC
 
-/* Integrity - at least one required.
+/* Message Integrity - at least one required.
- * RFC Draft requires sha1-hmac, and recommends md5-hmac.
+ * RFC Draft requires sha1 and recommends sha1-96.
+ * sha1-96 may be of use for slow links, as it has a smaller overhead.
  *
- * Note: there's no point disabling sha1 to save space, since it's used in the
+ * Note: there's no point disabling sha1 to save space, since it's used
  * for the random number generator and public-key cryptography anyway.
  * Disabling it here will just stop it from being used as the integrity portion
  * of the ssh protocol.
  *
- * These are also used for key fingerprints in logs (when pubkey auth is used),
+ * These hashes are also used for public key fingerprints in logs.
- * MD5 fingerprints are printed if available, however SHA1 fingerprints will be
+ * If you disable MD5, Dropbear will fall back to SHA1 fingerprints,
- * generated otherwise. This isn't exactly optimal, although SHA1 fingerprints
+ * which are not the standard form. */
- * are not too hard to create from pubkeys if required. */
 #define DROPBEAR_SHA1_HMAC
+#define DROPBEAR_SHA1_96_HMAC
 #define DROPBEAR_MD5_HMAC
 
 /* Hostkey/public key algorithms - at least one required, these are used
@@ -310,6 +315,14 @@ etc) slower (perhaps by 50%). Recommended for most small systems. */
 
 #define DROPBEAR_MAX_CLI_PASS 1024
 
+#if defined(DROPBEAR_AES256_CBC) || defined(DROPBEAR_AES128_CBC)
+#define DROPBEAR_AES_CBC
+#endif
+
+#if defined(DROPBEAR_TWOFISH256_CBC) || defined(DROPBEAR_TWOFISH128_CBC)
+#define DROPBEAR_TWOFISH_CBC
+#endif
+
 #ifndef ENABLE_X11FWD
 #define DISABLE_X11FWD
 #endif

packet.c

@@ -215,7 +215,7 @@ static void read_packet_init() {
 	if ((len > MAX_PACKET_LEN) ||
 		(len < MIN_PACKET_LEN + macsize) ||
 		((len - macsize) % blocksize != 0)) {
-		dropbear_exit("bad packet size");
+		dropbear_exit("bad packet size %d", len);
 	}
 
 	buf_resize(ses.readbuf, len);
@@ -314,14 +314,13 @@ void decrypt_packet() {
  * Returns DROPBEAR_SUCCESS or DROPBEAR_FAILURE */
 static int checkmac(buffer* macbuf, buffer* sourcebuf) {
 
-	unsigned char macsize;
+	unsigned int macsize;
 	hmac_state hmac;
 	unsigned char tempbuf[MAX_MAC_LEN];
-	unsigned long hashsize;
+	unsigned long bufsize;
-	int len;
+	unsigned int len;
 
 	macsize = ses.keys->recv_algo_mac->hashsize;
-
 	if (macsize == 0) {
 		return DROPBEAR_SUCCESS;
 	}
@@ -347,8 +346,8 @@ static int checkmac(buffer* macbuf, buffer* sourcebuf) {
 		dropbear_exit("HMAC error");
 	}
 
-	hashsize = sizeof(tempbuf);
+	bufsize = sizeof(tempbuf);
-	if (hmac_done(&hmac, tempbuf, &hashsize) != CRYPT_OK) {
+	if (hmac_done(&hmac, tempbuf, &bufsize) != CRYPT_OK) {
 		dropbear_exit("HMAC error");
 	}
 
@@ -524,15 +523,15 @@ void encrypt_packet() {
 /* Create the packet mac, and append H(seqno|clearbuf) to the output */
 static void writemac(buffer * outputbuffer, buffer * clearwritebuf) {
 
-	int macsize;
+	unsigned int macsize;
 	unsigned char seqbuf[4];
-	unsigned long hashsize;
+	unsigned char tempbuf[MAX_MAC_LEN];
+	unsigned long bufsize;
 	hmac_state hmac;
 
 	TRACE(("enter writemac"))
 
-	macsize = ses.keys->trans_algo_mac->hashsize;
+	macsize = ses.keys->recv_algo_mac->hashsize;
-
 	if (macsize > 0) {
 		/* calculate the mac */
 		if (hmac_init(&hmac, 
@@ -557,12 +556,12 @@ static void writemac(buffer * outputbuffer, buffer * clearwritebuf) {
 			dropbear_exit("HMAC error");
 		}
 	
-		hashsize = macsize;
+		bufsize = sizeof(tempbuf);
-		if (hmac_done(&hmac, buf_getwriteptr(outputbuffer, macsize), &hashsize) 
+		if (hmac_done(&hmac, tempbuf, &bufsize) 
 				!= CRYPT_OK) {
 			dropbear_exit("HMAC error");
 		}
-		buf_incrwritepos(outputbuffer, macsize);
+		buf_putbytes(outputbuffer, tempbuf, macsize);
 	}
 	TRACE(("leave writemac"))
 }