- markus@cvs.openbsd.org 2003/05/15 03:08:29

[openssh.git] / cipher-aes.c

diff --git a/cipher-aes.c b/cipher-aes.c
new file mode 100644 (file)
index 0000000..bbfbe72
--- /dev/null
+++ b/cipher-aes.c
@@ -0,0 +1,156 @@
+/*
+ * Copyright (c) 2003 Markus Friedl.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#if OPENSSL_VERSION_NUMBER < 0x00907000L
+#include "includes.h"
+RCSID("$OpenBSD: cipher-aes.c,v 1.1 2003/05/15 03:08:29 markus Exp $");
+
+#include <openssl/evp.h>
+#include "rijndael.h"
+#include "xmalloc.h"
+#include "log.h"
+
+#define RIJNDAEL_BLOCKSIZE 16
+struct ssh_rijndael_ctx
+{
+       rijndael_ctx    r_ctx;
+       u_char          r_iv[RIJNDAEL_BLOCKSIZE];
+};
+
+const EVP_CIPHER * evp_rijndael(void);
+void ssh_rijndael_iv(EVP_CIPHER_CTX *, int, u_char *, u_int);
+
+static int
+ssh_rijndael_init(EVP_CIPHER_CTX *ctx, const u_char *key, const u_char *iv,
+    int enc)
+{
+       struct ssh_rijndael_ctx *c;
+
+       if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) == NULL) {
+               c = xmalloc(sizeof(*c));
+               EVP_CIPHER_CTX_set_app_data(ctx, c);
+       }
+       if (key != NULL) {
+               if (enc == -1)
+                       enc = ctx->encrypt;
+               rijndael_set_key(&c->r_ctx, (u_char *)key,
+                   8*EVP_CIPHER_CTX_key_length(ctx), enc);
+       }
+       if (iv != NULL)
+               memcpy(c->r_iv, iv, RIJNDAEL_BLOCKSIZE);
+       return (1);
+}
+
+static int
+ssh_rijndael_cbc(EVP_CIPHER_CTX *ctx, u_char *dest, const u_char *src,
+    u_int len)
+{
+       struct ssh_rijndael_ctx *c;
+       u_char buf[RIJNDAEL_BLOCKSIZE];
+       u_char *cprev, *cnow, *plain, *ivp;
+       int i, j, blocks = len / RIJNDAEL_BLOCKSIZE;
+
+       if (len == 0)
+               return (1);
+       if (len % RIJNDAEL_BLOCKSIZE)
+               fatal("ssh_rijndael_cbc: bad len %d", len);
+       if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) == NULL) {
+               error("ssh_rijndael_cbc: no context");
+               return (0);
+       }
+       if (ctx->encrypt) {
+               cnow  = dest;
+               plain = (u_char *)src;
+               cprev = c->r_iv;
+               for (i = 0; i < blocks; i++, plain+=RIJNDAEL_BLOCKSIZE,
+                   cnow+=RIJNDAEL_BLOCKSIZE) {
+                       for (j = 0; j < RIJNDAEL_BLOCKSIZE; j++)
+                               buf[j] = plain[j] ^ cprev[j];
+                       rijndael_encrypt(&c->r_ctx, buf, cnow);
+                       cprev = cnow;
+               }
+               memcpy(c->r_iv, cprev, RIJNDAEL_BLOCKSIZE);
+       } else {
+               cnow  = (u_char *) (src+len-RIJNDAEL_BLOCKSIZE);
+               plain = dest+len-RIJNDAEL_BLOCKSIZE;
+
+               memcpy(buf, cnow, RIJNDAEL_BLOCKSIZE);
+               for (i = blocks; i > 0; i--, cnow-=RIJNDAEL_BLOCKSIZE,
+                   plain-=RIJNDAEL_BLOCKSIZE) {
+                       rijndael_decrypt(&c->r_ctx, cnow, plain);
+                       ivp = (i == 1) ? c->r_iv : cnow-RIJNDAEL_BLOCKSIZE;
+                       for (j = 0; j < RIJNDAEL_BLOCKSIZE; j++)
+                               plain[j] ^= ivp[j];
+               }
+               memcpy(c->r_iv, buf, RIJNDAEL_BLOCKSIZE);
+       }
+       return (1);
+}
+
+static int
+ssh_rijndael_cleanup(EVP_CIPHER_CTX *ctx)
+{
+       struct ssh_rijndael_ctx *c;
+
+       if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) != NULL) {
+               memset(c, 0, sizeof(*c));
+               xfree(c);
+               EVP_CIPHER_CTX_set_app_data(ctx, NULL);
+       }
+       return (1);
+}
+
+void
+ssh_rijndael_iv(EVP_CIPHER_CTX *evp, int doset, u_char * iv, u_int len)
+{
+       struct ssh_rijndael_ctx *c;
+
+       if ((c = EVP_CIPHER_CTX_get_app_data(evp)) == NULL)
+               fatal("ssh_rijndael_iv: no context");
+       if (doset)
+               memcpy(c->r_iv, iv, len);
+       else
+               memcpy(iv, c->r_iv, len);
+}
+
+const EVP_CIPHER *
+evp_rijndael(void)
+{
+       static EVP_CIPHER rijndal_cbc;
+
+       memset(&rijndal_cbc, 0, sizeof(EVP_CIPHER));
+       rijndal_cbc.nid = NID_undef;
+       rijndal_cbc.block_size = RIJNDAEL_BLOCKSIZE;
+       rijndal_cbc.iv_len = RIJNDAEL_BLOCKSIZE;
+       rijndal_cbc.key_len = 16;
+       rijndal_cbc.init = ssh_rijndael_init;
+       rijndal_cbc.cleanup = ssh_rijndael_cleanup;
+       rijndal_cbc.do_cipher = ssh_rijndael_cbc;
+#ifndef SSH_OLD_EVP
+       rijndal_cbc.flags = EVP_CIPH_CBC_MODE | EVP_CIPH_VARIABLE_LENGTH |
+           EVP_CIPH_ALWAYS_CALL_INIT | EVP_CIPH_CUSTOM_IV;
+#endif
+       return (&rijndal_cbc);
+}
+#endif