- 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