- djm@cvs.openbsd.org 2005/05/23 23:32:46

     [cipher.c myproposal.h ssh.1 ssh_config.5 sshd_config.5]
     add support for draft-harris-ssh-arcfour-fixes-02 improved arcfour modes;
     ok markus@

1 files changed, 38 insertions, 23 deletions

diff --git a/cipher.c b/cipher.c
index beba4618d..b56492940 100644
--- a/cipher.c
+++ b/cipher.c
@@ -35,7 +35,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: cipher.c,v 1.73 2005/01/23 10:18:12 djm Exp $");
+RCSID("$OpenBSD: cipher.c,v 1.74 2005/05/23 23:32:46 djm Exp $");
 
 #include "xmalloc.h"
 #include "log.h"
@@ -74,39 +74,42 @@ struct Cipher {
 	int	number;		/* for ssh1 only */
 	u_int	block_size;
 	u_int	key_len;
+	u_int	discard_len;
 	const EVP_CIPHER	*(*evptype)(void);
 } ciphers[] = {
-	{ "none",		SSH_CIPHER_NONE, 8, 0, EVP_enc_null },
-	{ "des",		SSH_CIPHER_DES, 8, 8, EVP_des_cbc },
-	{ "3des",		SSH_CIPHER_3DES, 8, 16, evp_ssh1_3des },
-	{ "blowfish",		SSH_CIPHER_BLOWFISH, 8, 32, evp_ssh1_bf },
-
-	{ "3des-cbc",		SSH_CIPHER_SSH2, 8, 24, EVP_des_ede3_cbc },
-	{ "blowfish-cbc",	SSH_CIPHER_SSH2, 8, 16, EVP_bf_cbc },
-	{ "cast128-cbc",	SSH_CIPHER_SSH2, 8, 16, EVP_cast5_cbc },
-	{ "arcfour",		SSH_CIPHER_SSH2, 8, 16, EVP_rc4 },
+	{ "none",		SSH_CIPHER_NONE, 8, 0, 0, EVP_enc_null },
+	{ "des",		SSH_CIPHER_DES, 8, 8, 0, EVP_des_cbc },
+	{ "3des",		SSH_CIPHER_3DES, 8, 16, 0, evp_ssh1_3des },
+	{ "blowfish",		SSH_CIPHER_BLOWFISH, 8, 32, 0, evp_ssh1_bf },
+
+	{ "3des-cbc",		SSH_CIPHER_SSH2, 8, 24, 0, EVP_des_ede3_cbc },
+	{ "blowfish-cbc",	SSH_CIPHER_SSH2, 8, 16, 0, EVP_bf_cbc },
+	{ "cast128-cbc",	SSH_CIPHER_SSH2, 8, 16, 0, EVP_cast5_cbc },
+	{ "arcfour",		SSH_CIPHER_SSH2, 8, 16, 0, EVP_rc4 },
+	{ "arcfour128",		SSH_CIPHER_SSH2, 8, 16, 1536, EVP_rc4 },
+	{ "arcfour256",		SSH_CIPHER_SSH2, 8, 32, 1536, EVP_rc4 },
 #if OPENSSL_VERSION_NUMBER < 0x00907000L
-	{ "aes128-cbc",		SSH_CIPHER_SSH2, 16, 16, evp_rijndael },
-	{ "aes192-cbc",		SSH_CIPHER_SSH2, 16, 24, evp_rijndael },
-	{ "aes256-cbc",		SSH_CIPHER_SSH2, 16, 32, evp_rijndael },
+	{ "aes128-cbc",		SSH_CIPHER_SSH2, 16, 16, 0, evp_rijndael },
+	{ "aes192-cbc",		SSH_CIPHER_SSH2, 16, 24, 0, evp_rijndael },
+	{ "aes256-cbc",		SSH_CIPHER_SSH2, 16, 32, 0, evp_rijndael },
 	{ "rijndael-cbc@lysator.liu.se",
-				SSH_CIPHER_SSH2, 16, 32, evp_rijndael },
+				SSH_CIPHER_SSH2, 16, 32, 0, evp_rijndael },
 #else
-	{ "aes128-cbc",		SSH_CIPHER_SSH2, 16, 16, EVP_aes_128_cbc },
-	{ "aes192-cbc",		SSH_CIPHER_SSH2, 16, 24, EVP_aes_192_cbc },
-	{ "aes256-cbc",		SSH_CIPHER_SSH2, 16, 32, EVP_aes_256_cbc },
+	{ "aes128-cbc",		SSH_CIPHER_SSH2, 16, 16, 0, EVP_aes_128_cbc },
+	{ "aes192-cbc",		SSH_CIPHER_SSH2, 16, 24, 0, EVP_aes_192_cbc },
+	{ "aes256-cbc",		SSH_CIPHER_SSH2, 16, 32, 0, EVP_aes_256_cbc },
 	{ "rijndael-cbc@lysator.liu.se",
-				SSH_CIPHER_SSH2, 16, 32, EVP_aes_256_cbc },
+				SSH_CIPHER_SSH2, 16, 32, 0, EVP_aes_256_cbc },
 #endif
 #if OPENSSL_VERSION_NUMBER >= 0x00905000L
-	{ "aes128-ctr",		SSH_CIPHER_SSH2, 16, 16, evp_aes_128_ctr },
-	{ "aes192-ctr",		SSH_CIPHER_SSH2, 16, 24, evp_aes_128_ctr },
-	{ "aes256-ctr",		SSH_CIPHER_SSH2, 16, 32, evp_aes_128_ctr },
+	{ "aes128-ctr",		SSH_CIPHER_SSH2, 16, 16, 0, evp_aes_128_ctr },
+	{ "aes192-ctr",		SSH_CIPHER_SSH2, 16, 24, 0, evp_aes_128_ctr },
+	{ "aes256-ctr",		SSH_CIPHER_SSH2, 16, 32, 0, evp_aes_128_ctr },
 #endif
 #if defined(EVP_CTRL_SET_ACSS_MODE)
-	{ "acss@openssh.org",	SSH_CIPHER_SSH2, 16, 5, EVP_acss },
+	{ "acss@openssh.org",	SSH_CIPHER_SSH2, 16, 5, 0, EVP_acss },
 #endif
-	{ NULL,			SSH_CIPHER_INVALID, 0, 0, NULL }
+	{ NULL,			SSH_CIPHER_INVALID, 0, 0, 0, NULL }
 };
 
 /*--*/
@@ -224,6 +227,7 @@ cipher_init(CipherContext *cc, Cipher *cipher,
 	const EVP_CIPHER *type;
 #endif
 	int klen;
+	u_char *junk, *discard;
 
 	if (cipher->number == SSH_CIPHER_DES) {
 		if (dowarn) {
@@ -271,6 +275,17 @@ cipher_init(CipherContext *cc, Cipher *cipher,
 		fatal("cipher_init: EVP_CipherInit: set key failed for %s",
 		    cipher->name);
 #endif
+
+	if (cipher->discard_len > 0) {		
+		junk = xmalloc(cipher->discard_len);
+		discard = xmalloc(cipher->discard_len);
+		if (EVP_Cipher(&cc->evp, discard, junk,
+		    cipher->discard_len) == 0)
+			fatal("evp_crypt: EVP_Cipher failed during discard");
+		memset(discard, 0, cipher->discard_len);
+		xfree(junk);
+		xfree(discard);
+	}
 }
 
 void