/*
- *
- * cipher.c
- *
* Author: Tatu Ylonen <ylo@cs.hut.fi>
- *
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
- *
- * Created: Wed Apr 19 17:41:39 1995 ylo
- *
+ *
+ * As far as I am concerned, the code I have written for this software
+ * can be used freely for any purpose. Any derived versions of this
+ * software must be clearly marked as such, and if the derived work is
+ * incompatible with the protocol description in the RFC file, it must be
+ * called by a name other than "ssh" or "Secure Shell".
+ *
+ *
+ * Copyright (c) 1999 Niels Provos. All rights reserved.
+ * Copyright (c) 1999, 2000 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.
*/
#include "includes.h"
-RCSID("$Id$");
+RCSID("$OpenBSD: cipher.c,v 1.48 2001/12/19 07:18:56 deraadt Exp $");
-#include "ssh.h"
+#include "xmalloc.h"
+#include "log.h"
#include "cipher.h"
-#include "config.h"
-#ifdef HAVE_OPENSSL
#include <openssl/md5.h>
-#endif
-#ifdef HAVE_SSL
-#include <ssl/md5.h>
-#endif
+
+/* no encryption */
+static void
+none_setkey(CipherContext *cc, const u_char *key, u_int keylen)
+{
+}
+static void
+none_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
+{
+}
+static void
+none_crypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
+{
+ memcpy(dest, src, len);
+}
+
+/* DES */
+static void
+des_ssh1_setkey(CipherContext *cc, const u_char *key, u_int keylen)
+{
+ static int dowarn = 1;
+ if (dowarn) {
+ error("Warning: use of DES is strongly discouraged "
+ "due to cryptographic weaknesses");
+ dowarn = 0;
+ }
+ des_set_key((void *)key, cc->u.des.key);
+}
+static void
+des_ssh1_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
+{
+ memset(cc->u.des.iv, 0, sizeof(cc->u.des.iv));
+}
+static void
+des_ssh1_encrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
+{
+ des_ncbc_encrypt(src, dest, len, cc->u.des.key, &cc->u.des.iv,
+ DES_ENCRYPT);
+}
+static void
+des_ssh1_decrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
+{
+ des_ncbc_encrypt(src, dest, len, cc->u.des.key, &cc->u.des.iv,
+ DES_DECRYPT);
+}
+
+/* 3DES */
+static void
+des3_setkey(CipherContext *cc, const u_char *key, u_int keylen)
+{
+ des_set_key((void *) key, cc->u.des3.key1);
+ des_set_key((void *) (key+8), cc->u.des3.key2);
+ des_set_key((void *) (key+16), cc->u.des3.key3);
+}
+static void
+des3_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
+{
+ memset(cc->u.des3.iv1, 0, sizeof(cc->u.des3.iv1));
+ memset(cc->u.des3.iv2, 0, sizeof(cc->u.des3.iv2));
+ memset(cc->u.des3.iv3, 0, sizeof(cc->u.des3.iv3));
+ if (iv == NULL)
+ return;
+ memcpy(cc->u.des3.iv3, (char *)iv, 8);
+}
+static void
+des3_cbc_encrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
+{
+ des_ede3_cbc_encrypt(src, dest, len,
+ cc->u.des3.key1, cc->u.des3.key2, cc->u.des3.key3,
+ &cc->u.des3.iv3, DES_ENCRYPT);
+}
+static void
+des3_cbc_decrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
+{
+ des_ede3_cbc_encrypt(src, dest, len,
+ cc->u.des3.key1, cc->u.des3.key2, cc->u.des3.key3,
+ &cc->u.des3.iv3, DES_DECRYPT);
+}
/*
- * What kind of tripple DES are these 2 routines?
+ * This is used by SSH1:
+ *
+ * What kind of triple DES are these 2 routines?
*
* Why is there a redundant initialization vector?
*
* result of that there is no longer any known iv1 to use when
* choosing the X block.
*/
-void
-SSH_3CBC_ENCRYPT(des_key_schedule ks1,
- des_key_schedule ks2, des_cblock * iv2,
- des_key_schedule ks3, des_cblock * iv3,
- unsigned char *dest, unsigned char *src,
- unsigned int len)
+static void
+des3_ssh1_setkey(CipherContext *cc, const u_char *key, u_int keylen)
{
- des_cblock iv1;
-
- memcpy(&iv1, iv2, 8);
-
- des_cbc_encrypt(src, dest, len, ks1, &iv1, DES_ENCRYPT);
- memcpy(&iv1, dest + len - 8, 8);
+ des_set_key((void *) key, cc->u.des3.key1);
+ des_set_key((void *) (key+8), cc->u.des3.key2);
+ if (keylen <= 16)
+ des_set_key((void *) key, cc->u.des3.key3);
+ else
+ des_set_key((void *) (key+16), cc->u.des3.key3);
+}
+static void
+des3_ssh1_encrypt(CipherContext *cc, u_char *dest, const u_char *src,
+ u_int len)
+{
+ des_ncbc_encrypt(src, dest, len, cc->u.des3.key1, &cc->u.des3.iv1,
+ DES_ENCRYPT);
+ des_ncbc_encrypt(dest, dest, len, cc->u.des3.key2, &cc->u.des3.iv2,
+ DES_DECRYPT);
+ des_ncbc_encrypt(dest, dest, len, cc->u.des3.key3, &cc->u.des3.iv3,
+ DES_ENCRYPT);
+}
+static void
+des3_ssh1_decrypt(CipherContext *cc, u_char *dest, const u_char *src,
+ u_int len)
+{
+ des_ncbc_encrypt(src, dest, len, cc->u.des3.key3, &cc->u.des3.iv3,
+ DES_DECRYPT);
+ des_ncbc_encrypt(dest, dest, len, cc->u.des3.key2, &cc->u.des3.iv2,
+ DES_ENCRYPT);
+ des_ncbc_encrypt(dest, dest, len, cc->u.des3.key1, &cc->u.des3.iv1,
+ DES_DECRYPT);
+}
- des_cbc_encrypt(dest, dest, len, ks2, iv2, DES_DECRYPT);
- memcpy(iv2, &iv1, 8); /* Note how iv1 == iv2 on entry and exit. */
+/* Blowfish */
+static void
+blowfish_setkey(CipherContext *cc, const u_char *key, u_int keylen)
+{
+ BF_set_key(&cc->u.bf.key, keylen, (u_char *)key);
+}
+static void
+blowfish_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
+{
+ if (iv == NULL)
+ memset(cc->u.bf.iv, 0, 8);
+ else
+ memcpy(cc->u.bf.iv, (char *)iv, 8);
+}
+static void
+blowfish_cbc_encrypt(CipherContext *cc, u_char *dest, const u_char *src,
+ u_int len)
+{
+ BF_cbc_encrypt((void *)src, dest, len, &cc->u.bf.key, cc->u.bf.iv,
+ BF_ENCRYPT);
+}
+static void
+blowfish_cbc_decrypt(CipherContext *cc, u_char *dest, const u_char *src,
+ u_int len)
+{
+ BF_cbc_encrypt((void *)src, dest, len, &cc->u.bf.key, cc->u.bf.iv,
+ BF_DECRYPT);
+}
- des_cbc_encrypt(dest, dest, len, ks3, iv3, DES_ENCRYPT);
- memcpy(iv3, dest + len - 8, 8);
+/*
+ * SSH1 uses a variation on Blowfish, all bytes must be swapped before
+ * and after encryption/decryption. Thus the swap_bytes stuff (yuk).
+ */
+static void
+swap_bytes(const u_char *src, u_char *dst, int n)
+{
+ char c[4];
+
+ /* Process 4 bytes every lap. */
+ for (n = n / 4; n > 0; n--) {
+ c[3] = *src++;
+ c[2] = *src++;
+ c[1] = *src++;
+ c[0] = *src++;
+
+ *dst++ = c[0];
+ *dst++ = c[1];
+ *dst++ = c[2];
+ *dst++ = c[3];
+ }
}
-void
-SSH_3CBC_DECRYPT(des_key_schedule ks1,
- des_key_schedule ks2, des_cblock * iv2,
- des_key_schedule ks3, des_cblock * iv3,
- unsigned char *dest, unsigned char *src,
- unsigned int len)
+static void
+blowfish_ssh1_encrypt(CipherContext *cc, u_char *dest, const u_char *src,
+ u_int len)
{
- des_cblock iv1;
+ swap_bytes(src, dest, len);
+ BF_cbc_encrypt((void *)dest, dest, len, &cc->u.bf.key, cc->u.bf.iv,
+ BF_ENCRYPT);
+ swap_bytes(dest, dest, len);
+}
+static void
+blowfish_ssh1_decrypt(CipherContext *cc, u_char *dest, const u_char *src,
+ u_int len)
+{
+ swap_bytes(src, dest, len);
+ BF_cbc_encrypt((void *)dest, dest, len, &cc->u.bf.key, cc->u.bf.iv,
+ BF_DECRYPT);
+ swap_bytes(dest, dest, len);
+}
- memcpy(&iv1, iv2, 8);
+/* alleged rc4 */
+static void
+arcfour_setkey(CipherContext *cc, const u_char *key, u_int keylen)
+{
+ RC4_set_key(&cc->u.rc4, keylen, (u_char *)key);
+}
+static void
+arcfour_crypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
+{
+ RC4(&cc->u.rc4, len, (u_char *)src, dest);
+}
- des_cbc_encrypt(src, dest, len, ks3, iv3, DES_DECRYPT);
- memcpy(iv3, src + len - 8, 8);
+/* CAST */
+static void
+cast_setkey(CipherContext *cc, const u_char *key, u_int keylen)
+{
+ CAST_set_key(&cc->u.cast.key, keylen, (u_char *) key);
+}
+static void
+cast_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
+{
+ if (iv == NULL)
+ fatal("no IV for %s.", cc->cipher->name);
+ memcpy(cc->u.cast.iv, (char *)iv, 8);
+}
+static void
+cast_cbc_encrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
+{
+ CAST_cbc_encrypt(src, dest, len, &cc->u.cast.key, cc->u.cast.iv,
+ CAST_ENCRYPT);
+}
+static void
+cast_cbc_decrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
+{
+ CAST_cbc_encrypt(src, dest, len, &cc->u.cast.key, cc->u.cast.iv,
+ CAST_DECRYPT);
+}
- des_cbc_encrypt(dest, dest, len, ks2, iv2, DES_ENCRYPT);
- memcpy(iv2, dest + len - 8, 8);
+/* RIJNDAEL */
- des_cbc_encrypt(dest, dest, len, ks1, &iv1, DES_DECRYPT);
- /* memcpy(&iv1, iv2, 8); */
- /* Note how iv1 == iv2 on entry and exit. */
+#define RIJNDAEL_BLOCKSIZE 16
+static void
+rijndael_setkey(CipherContext *cc, const u_char *key, u_int keylen)
+{
+ rijndael_set_key(&cc->u.rijndael.enc, (char *)key, 8*keylen, 1);
+ rijndael_set_key(&cc->u.rijndael.dec, (char *)key, 8*keylen, 0);
+}
+static void
+rijndael_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
+{
+ if (iv == NULL || ivlen != RIJNDAEL_BLOCKSIZE)
+ fatal("bad/no IV for %s.", cc->cipher->name);
+ memcpy(cc->u.rijndael.iv, iv, RIJNDAEL_BLOCKSIZE);
}
-
-/*
- * SSH uses a variation on Blowfish, all bytes must be swapped before
- * and after encryption/decryption. Thus the swap_bytes stuff (yuk).
- */
static void
-swap_bytes(const unsigned char *src, unsigned char *dst_, int n)
-{
- /* dst must be properly aligned. */
- u_int32_t *dst = (u_int32_t *) dst_;
- union {
- u_int32_t i;
- char c[4];
- } t;
-
- /* Process 8 bytes every lap. */
- for (n = n / 8; n > 0; n--) {
- t.c[3] = *src++;
- t.c[2] = *src++;
- t.c[1] = *src++;
- t.c[0] = *src++;
- *dst++ = t.i;
-
- t.c[3] = *src++;
- t.c[2] = *src++;
- t.c[1] = *src++;
- t.c[0] = *src++;
- *dst++ = t.i;
+rijndael_cbc_encrypt(CipherContext *cc, u_char *dest, const u_char *src,
+ u_int len)
+{
+ rijndael_ctx *ctx = &cc->u.rijndael.enc;
+ u_char *iv = cc->u.rijndael.iv;
+ u_char in[RIJNDAEL_BLOCKSIZE];
+ u_char *cprev, *cnow, *plain;
+ int i, j, blocks = len / RIJNDAEL_BLOCKSIZE;
+
+ if (len == 0)
+ return;
+ if (len % RIJNDAEL_BLOCKSIZE)
+ fatal("rijndael_cbc_encrypt: bad len %d", len);
+ cnow = dest;
+ plain = (u_char *) src;
+ cprev = iv;
+ for (i = 0; i < blocks; i++, plain+=RIJNDAEL_BLOCKSIZE,
+ cnow+=RIJNDAEL_BLOCKSIZE) {
+ for (j = 0; j < RIJNDAEL_BLOCKSIZE; j++)
+ in[j] = plain[j] ^ cprev[j];
+ rijndael_encrypt(ctx, in, cnow);
+ cprev = cnow;
}
+ memcpy(iv, cprev, RIJNDAEL_BLOCKSIZE);
+}
+static void
+rijndael_cbc_decrypt(CipherContext *cc, u_char *dest, const u_char *src,
+ u_int len)
+{
+ rijndael_ctx *ctx = &cc->u.rijndael.dec;
+ u_char *iv = cc->u.rijndael.iv;
+ u_char ivsaved[RIJNDAEL_BLOCKSIZE];
+ u_char *cnow = (u_char *) (src+len-RIJNDAEL_BLOCKSIZE);
+ u_char *plain = dest+len-RIJNDAEL_BLOCKSIZE;
+ u_char *ivp;
+ int i, j, blocks = len / RIJNDAEL_BLOCKSIZE;
+
+ if (len == 0)
+ return;
+ if (len % RIJNDAEL_BLOCKSIZE)
+ fatal("rijndael_cbc_decrypt: bad len %d", len);
+ memcpy(ivsaved, cnow, RIJNDAEL_BLOCKSIZE);
+ for (i = blocks; i > 0; i--, cnow-=RIJNDAEL_BLOCKSIZE,
+ plain-=RIJNDAEL_BLOCKSIZE) {
+ rijndael_decrypt(ctx, cnow, plain);
+ ivp = (i == 1) ? iv : cnow-RIJNDAEL_BLOCKSIZE;
+ for (j = 0; j < RIJNDAEL_BLOCKSIZE; j++)
+ plain[j] ^= ivp[j];
+ }
+ memcpy(iv, ivsaved, RIJNDAEL_BLOCKSIZE);
}
-/*
- * Names of all encryption algorithms.
- * These must match the numbers defined in cipher.h.
- */
-static char *cipher_names[] =
-{
- "none",
- "idea",
- "des",
- "3des",
- "tss",
- "rc4",
- "blowfish"
+Cipher ciphers[] = {
+ { "none",
+ SSH_CIPHER_NONE, 8, 0,
+ none_setkey, none_setiv,
+ none_crypt, none_crypt },
+ { "des",
+ SSH_CIPHER_DES, 8, 8,
+ des_ssh1_setkey, des_ssh1_setiv,
+ des_ssh1_encrypt, des_ssh1_decrypt },
+ { "3des",
+ SSH_CIPHER_3DES, 8, 16,
+ des3_ssh1_setkey, des3_setiv,
+ des3_ssh1_encrypt, des3_ssh1_decrypt },
+ { "blowfish",
+ SSH_CIPHER_BLOWFISH, 8, 16,
+ blowfish_setkey, blowfish_setiv,
+ blowfish_ssh1_encrypt, blowfish_ssh1_decrypt },
+
+ { "3des-cbc",
+ SSH_CIPHER_SSH2, 8, 24,
+ des3_setkey, des3_setiv,
+ des3_cbc_encrypt, des3_cbc_decrypt },
+ { "blowfish-cbc",
+ SSH_CIPHER_SSH2, 8, 16,
+ blowfish_setkey, blowfish_setiv,
+ blowfish_cbc_encrypt, blowfish_cbc_decrypt },
+ { "cast128-cbc",
+ SSH_CIPHER_SSH2, 8, 16,
+ cast_setkey, cast_setiv,
+ cast_cbc_encrypt, cast_cbc_decrypt },
+ { "arcfour",
+ SSH_CIPHER_SSH2, 8, 16,
+ arcfour_setkey, none_setiv,
+ arcfour_crypt, arcfour_crypt },
+ { "aes128-cbc",
+ SSH_CIPHER_SSH2, 16, 16,
+ rijndael_setkey, rijndael_setiv,
+ rijndael_cbc_encrypt, rijndael_cbc_decrypt },
+ { "aes192-cbc",
+ SSH_CIPHER_SSH2, 16, 24,
+ rijndael_setkey, rijndael_setiv,
+ rijndael_cbc_encrypt, rijndael_cbc_decrypt },
+ { "aes256-cbc",
+ SSH_CIPHER_SSH2, 16, 32,
+ rijndael_setkey, rijndael_setiv,
+ rijndael_cbc_encrypt, rijndael_cbc_decrypt },
+ { "rijndael128-cbc",
+ SSH_CIPHER_SSH2, 16, 16,
+ rijndael_setkey, rijndael_setiv,
+ rijndael_cbc_encrypt, rijndael_cbc_decrypt },
+ { "rijndael192-cbc",
+ SSH_CIPHER_SSH2, 16, 24,
+ rijndael_setkey, rijndael_setiv,
+ rijndael_cbc_encrypt, rijndael_cbc_decrypt },
+ { "rijndael256-cbc",
+ SSH_CIPHER_SSH2, 16, 32,
+ rijndael_setkey, rijndael_setiv,
+ rijndael_cbc_encrypt, rijndael_cbc_decrypt },
+ { "rijndael-cbc@lysator.liu.se",
+ SSH_CIPHER_SSH2, 16, 32,
+ rijndael_setkey, rijndael_setiv,
+ rijndael_cbc_encrypt, rijndael_cbc_decrypt },
+ { NULL, SSH_CIPHER_ILLEGAL, 0, 0, NULL, NULL, NULL, NULL }
};
-/*
- * Returns a bit mask indicating which ciphers are supported by this
- * implementation. The bit mask has the corresponding bit set of each
- * supported cipher.
- */
+/*--*/
-unsigned int
-cipher_mask()
+u_int
+cipher_mask_ssh1(int client)
{
- unsigned int mask = 0;
+ u_int mask = 0;
mask |= 1 << SSH_CIPHER_3DES; /* Mandatory */
mask |= 1 << SSH_CIPHER_BLOWFISH;
+ if (client) {
+ mask |= 1 << SSH_CIPHER_DES;
+ }
return mask;
}
-/* Returns the name of the cipher. */
+Cipher *
+cipher_by_name(const char *name)
+{
+ Cipher *c;
+ for (c = ciphers; c->name != NULL; c++)
+ if (strcasecmp(c->name, name) == 0)
+ return c;
+ return NULL;
+}
+
+Cipher *
+cipher_by_number(int id)
+{
+ Cipher *c;
+ for (c = ciphers; c->name != NULL; c++)
+ if (c->number == id)
+ return c;
+ return NULL;
+}
-const char *
-cipher_name(int cipher)
+#define CIPHER_SEP ","
+int
+ciphers_valid(const char *names)
{
- if (cipher < 0 || cipher >= sizeof(cipher_names) / sizeof(cipher_names[0]) ||
- cipher_names[cipher] == NULL)
- fatal("cipher_name: bad cipher number: %d", cipher);
- return cipher_names[cipher];
+ Cipher *c;
+ char *ciphers, *cp;
+ char *p;
+
+ if (names == NULL || strcmp(names, "") == 0)
+ return 0;
+ ciphers = cp = xstrdup(names);
+ for ((p = strsep(&cp, CIPHER_SEP)); p && *p != '\0';
+ (p = strsep(&cp, CIPHER_SEP))) {
+ c = cipher_by_name(p);
+ if (c == NULL || c->number != SSH_CIPHER_SSH2) {
+ debug("bad cipher %s [%s]", p, names);
+ xfree(ciphers);
+ return 0;
+ } else {
+ debug3("cipher ok: %s [%s]", p, names);
+ }
+ }
+ debug3("ciphers ok: [%s]", names);
+ xfree(ciphers);
+ return 1;
}
/*
int
cipher_number(const char *name)
{
- int i;
- for (i = 0; i < sizeof(cipher_names) / sizeof(cipher_names[0]); i++)
- if (strcmp(cipher_names[i], name) == 0 &&
- (cipher_mask() & (1 << i)))
- return i;
- return -1;
+ Cipher *c;
+ if (name == NULL)
+ return -1;
+ c = cipher_by_name(name);
+ return (c==NULL) ? -1 : c->number;
+}
+
+char *
+cipher_name(int id)
+{
+ Cipher *c = cipher_by_number(id);
+ return (c==NULL) ? "<unknown>" : c->name;
+}
+
+void
+cipher_init(CipherContext *cc, Cipher *cipher,
+ const u_char *key, u_int keylen, const u_char *iv, u_int ivlen)
+{
+ if (keylen < cipher->key_len)
+ fatal("cipher_init: key length %d is insufficient for %s.",
+ keylen, cipher->name);
+ if (iv != NULL && ivlen < cipher->block_size)
+ fatal("cipher_init: iv length %d is insufficient for %s.",
+ ivlen, cipher->name);
+ cc->cipher = cipher;
+ cipher->setkey(cc, key, keylen);
+ cipher->setiv(cc, iv, ivlen);
+}
+
+void
+cipher_encrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
+{
+ if (len % cc->cipher->block_size)
+ fatal("cipher_encrypt: bad plaintext length %d", len);
+ cc->cipher->encrypt(cc, dest, src, len);
+}
+
+void
+cipher_decrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
+{
+ if (len % cc->cipher->block_size)
+ fatal("cipher_decrypt: bad ciphertext length %d", len);
+ cc->cipher->decrypt(cc, dest, src, len);
}
/*
* passphrase and using the resulting 16 bytes as the key.
*/
-void
-cipher_set_key_string(CipherContext *context, int cipher,
- const char *passphrase, int for_encryption)
+void
+cipher_set_key_string(CipherContext *cc, Cipher *cipher,
+ const char *passphrase)
{
MD5_CTX md;
- unsigned char digest[16];
+ u_char digest[16];
MD5_Init(&md);
- MD5_Update(&md, (const unsigned char *) passphrase, strlen(passphrase));
+ MD5_Update(&md, (const u_char *)passphrase, strlen(passphrase));
MD5_Final(digest, &md);
- cipher_set_key(context, cipher, digest, 16, for_encryption);
+ cipher_init(cc, cipher, digest, 16, NULL, 0);
memset(digest, 0, sizeof(digest));
memset(&md, 0, sizeof(md));
}
-
-/* Selects the cipher to use and sets the key. */
-
-void
-cipher_set_key(CipherContext *context, int cipher,
- const unsigned char *key, int keylen, int for_encryption)
-{
- unsigned char padded[32];
-
- /* Set cipher type. */
- context->type = cipher;
-
- /* Get 32 bytes of key data. Pad if necessary. (So that code
- below does not need to worry about key size). */
- memset(padded, 0, sizeof(padded));
- memcpy(padded, key, keylen < sizeof(padded) ? keylen : sizeof(padded));
-
- /* Initialize the initialization vector. */
- switch (cipher) {
- case SSH_CIPHER_NONE:
- /*
- * Has to stay for authfile saving of private key with no
- * passphrase
- */
- break;
-
- case SSH_CIPHER_3DES:
- /*
- * Note: the least significant bit of each byte of key is
- * parity, and must be ignored by the implementation. 16
- * bytes of key are used (first and last keys are the same).
- */
- if (keylen < 16)
- error("Key length %d is insufficient for 3DES.", keylen);
- des_set_key((void *) padded, context->u.des3.key1);
- des_set_key((void *) (padded + 8), context->u.des3.key2);
- if (keylen <= 16)
- des_set_key((void *) padded, context->u.des3.key3);
- else
- des_set_key((void *) (padded + 16), context->u.des3.key3);
- memset(context->u.des3.iv2, 0, sizeof(context->u.des3.iv2));
- memset(context->u.des3.iv3, 0, sizeof(context->u.des3.iv3));
- break;
-
- case SSH_CIPHER_BLOWFISH:
- BF_set_key(&context->u.bf.key, keylen, padded);
- memset(context->u.bf.iv, 0, 8);
- break;
-
- default:
- fatal("cipher_set_key: unknown cipher: %s", cipher_name(cipher));
- }
- memset(padded, 0, sizeof(padded));
-}
-
-/* Encrypts data using the cipher. */
-
-void
-cipher_encrypt(CipherContext *context, unsigned char *dest,
- const unsigned char *src, unsigned int len)
-{
- if ((len & 7) != 0)
- fatal("cipher_encrypt: bad plaintext length %d", len);
-
- switch (context->type) {
- case SSH_CIPHER_NONE:
- memcpy(dest, src, len);
- break;
-
- case SSH_CIPHER_3DES:
- SSH_3CBC_ENCRYPT(context->u.des3.key1,
- context->u.des3.key2, &context->u.des3.iv2,
- context->u.des3.key3, &context->u.des3.iv3,
- dest, (unsigned char *) src, len);
- break;
-
- case SSH_CIPHER_BLOWFISH:
- swap_bytes(src, dest, len);
- BF_cbc_encrypt(dest, dest, len,
- &context->u.bf.key, context->u.bf.iv,
- BF_ENCRYPT);
- swap_bytes(dest, dest, len);
- break;
-
- default:
- fatal("cipher_encrypt: unknown cipher: %s", cipher_name(context->type));
- }
-}
-
-/* Decrypts data using the cipher. */
-
-void
-cipher_decrypt(CipherContext *context, unsigned char *dest,
- const unsigned char *src, unsigned int len)
-{
- if ((len & 7) != 0)
- fatal("cipher_decrypt: bad ciphertext length %d", len);
-
- switch (context->type) {
- case SSH_CIPHER_NONE:
- memcpy(dest, src, len);
- break;
-
- case SSH_CIPHER_3DES:
- SSH_3CBC_DECRYPT(context->u.des3.key1,
- context->u.des3.key2, &context->u.des3.iv2,
- context->u.des3.key3, &context->u.des3.iv3,
- dest, (unsigned char *) src, len);
- break;
-
- case SSH_CIPHER_BLOWFISH:
- swap_bytes(src, dest, len);
- BF_cbc_encrypt((void *) dest, dest, len,
- &context->u.bf.key, context->u.bf.iv,
- BF_DECRYPT);
- swap_bytes(dest, dest, len);
- break;
-
- default:
- fatal("cipher_decrypt: unknown cipher: %s", cipher_name(context->type));
- }
-}
andersk / openssh.git / blobdiff