- markus@cvs.openbsd.org 2003/05/17 04:27:52

     [cipher.c cipher-ctr.c myproposal.h]
     experimental support for aes-ctr modes from
     http://www.ietf.org/internet-drafts/draft-ietf-secsh-newmodes-00.txt
     ok djm@

1 files changed, 12 insertions, 1 deletions

diff --git a/cipher.c b/cipher.c
index acb436c8a..e7c3c5411 100644
--- a/cipher.c
+++ b/cipher.c
@@ -35,7 +35,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: cipher.c,v 1.64 2003/05/15 03:08:29 markus Exp $");
+RCSID("$OpenBSD: cipher.c,v 1.65 2003/05/17 04:27:52 markus Exp $");
 
 #include "xmalloc.h"
 #include "log.h"
@@ -55,6 +55,8 @@ extern void ssh_rijndael_iv(EVP_CIPHER_CTX *, int, u_char *, u_int);
 extern const EVP_CIPHER *evp_ssh1_bf(void);
 extern const EVP_CIPHER *evp_ssh1_3des(void);
 extern void ssh1_3des_iv(EVP_CIPHER_CTX *, int, u_char *, int);
+extern const EVP_CIPHER *evp_aes_128_ctr(void);
+extern void ssh_aes_ctr_iv(EVP_CIPHER_CTX *, int, u_char *, u_int);
 
 struct Cipher {
         char    *name;
@@ -85,6 +87,9 @@ struct Cipher {
         { "rijndael-cbc@lysator.liu.se",
                                 SSH_CIPHER_SSH2, 16, 32, EVP_aes_256_cbc },
 #endif
+        { "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 },
 
         { NULL,                 SSH_CIPHER_ILLEGAL, 0, 0, NULL }
 };
@@ -337,6 +342,9 @@ cipher_get_keyiv(CipherContext *cc, u_char *iv, u_int len)
                         ssh_rijndael_iv(&cc->evp, 0, iv, len);
                 else
 #endif
+                if (c->evptype == evp_aes_128_ctr)
+                        ssh_aes_ctr_iv(&cc->evp, 0, iv, len);
+                else
                         memcpy(iv, cc->evp.iv, len);
                 break;
         case SSH_CIPHER_3DES:
@@ -365,6 +373,9 @@ cipher_set_keyiv(CipherContext *cc, u_char *iv)
                         ssh_rijndael_iv(&cc->evp, 1, iv, evplen);
                 else
 #endif
+                if (c->evptype == evp_aes_128_ctr)
+                        ssh_aes_ctr_iv(&cc->evp, 1, iv, evplen);
+                else
                         memcpy(cc->evp.iv, iv, evplen);
                 break;
         case SSH_CIPHER_3DES: