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authorDamien Miller <djm@mindrot.org>2000-10-14 16:23:11 +1100
committerDamien Miller <djm@mindrot.org>2000-10-14 16:23:11 +1100
commit874d77bb134a21a5cf625956b60173376a993ba8 (patch)
tree93dd73b2ff1fbf0ad5f3978a2c4e0d8438a0bf7c /cipher.c
parent89d9796fbedef4eed6956a2c095c7cc25330c28d (diff)
- (djm) Big OpenBSD sync:
- markus@cvs.openbsd.org 2000/09/30 10:27:44 [log.c] allow loglevel debug - markus@cvs.openbsd.org 2000/10/03 11:59:57 [packet.c] hmac->mac - markus@cvs.openbsd.org 2000/10/03 12:03:03 [auth-krb4.c auth-passwd.c auth-rh-rsa.c auth-rhosts.c auth-rsa.c auth1.c] move fake-auth from auth1.c to individual auth methods, disables s/key in debug-msg - markus@cvs.openbsd.org 2000/10/03 12:16:48 ssh.c do not resolve canonname, i have no idea why this was added oin ossh - markus@cvs.openbsd.org 2000/10/09 15:30:44 ssh-keygen.1 ssh-keygen.c -X now reads private ssh.com DSA keys, too. - markus@cvs.openbsd.org 2000/10/09 15:32:34 auth-options.c clear options on every call. - markus@cvs.openbsd.org 2000/10/09 15:51:00 authfd.c authfd.h interop with ssh-agent2, from <res@shore.net> - markus@cvs.openbsd.org 2000/10/10 14:20:45 compat.c use rexexp for version string matching - provos@cvs.openbsd.org 2000/10/10 22:02:18 [kex.c kex.h myproposal.h ssh.h ssh2.h sshconnect2.c sshd.c dh.c dh.h] First rough implementation of the diffie-hellman group exchange. The client can ask the server for bigger groups to perform the diffie-hellman in, thus increasing the attack complexity when using ciphers with longer keys. University of Windsor provided network, T the company. - markus@cvs.openbsd.org 2000/10/11 13:59:52 [auth-rsa.c auth2.c] clear auth options unless auth sucessfull - markus@cvs.openbsd.org 2000/10/11 14:00:27 [auth-options.h] clear auth options unless auth sucessfull - markus@cvs.openbsd.org 2000/10/11 14:03:27 [scp.1 scp.c] support 'scp -o' with help from mouring@pconline.com - markus@cvs.openbsd.org 2000/10/11 14:11:35 [dh.c] Wall - markus@cvs.openbsd.org 2000/10/11 14:14:40 [auth.h auth2.c readconf.c readconf.h readpass.c servconf.c servconf.h] [ssh.h sshconnect2.c sshd_config auth2-skey.c cli.c cli.h] add support for s/key (kbd-interactive) to ssh2, based on work by mkiernan@avantgo.com and me - markus@cvs.openbsd.org 2000/10/11 14:27:24 [auth.c auth1.c auth2.c authfile.c cipher.c cipher.h kex.c kex.h] [myproposal.h packet.c readconf.c session.c ssh.c ssh.h sshconnect1.c] [sshconnect2.c sshd.c] new cipher framework - markus@cvs.openbsd.org 2000/10/11 14:45:21 [cipher.c] remove DES - markus@cvs.openbsd.org 2000/10/12 03:59:20 [cipher.c cipher.h sshconnect1.c sshconnect2.c sshd.c] enable DES in SSH-1 clients only - markus@cvs.openbsd.org 2000/10/12 08:21:13 [kex.h packet.c] remove unused - markus@cvs.openbsd.org 2000/10/13 12:34:46 [sshd.c] Kludge for F-Secure Macintosh < 1.0.2; appro@fy.chalmers.se - markus@cvs.openbsd.org 2000/10/13 12:59:15 [cipher.c cipher.h myproposal.h rijndael.c rijndael.h] rijndael/aes support - markus@cvs.openbsd.org 2000/10/13 13:10:54 [sshd.8] more info about -V - markus@cvs.openbsd.org 2000/10/13 13:12:02 [myproposal.h] prefer no compression
Diffstat (limited to 'cipher.c')
-rw-r--r--cipher.c707
1 files changed, 396 insertions, 311 deletions
diff --git a/cipher.c b/cipher.c
index c7985a79..226e4256 100644
--- a/cipher.c
+++ b/cipher.c
@@ -35,14 +35,91 @@
*/
#include "includes.h"
-RCSID("$OpenBSD: cipher.c,v 1.31 2000/09/12 00:38:32 deraadt Exp $");
+RCSID("$OpenBSD: cipher.c,v 1.35 2000/10/13 18:59:13 markus Exp $");
#include "ssh.h"
-#include "cipher.h"
#include "xmalloc.h"
#include <openssl/md5.h>
+
+/* no encryption */
+void
+none_setkey(CipherContext *cc, const u_char *key, u_int keylen)
+{
+}
+void
+none_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
+{
+}
+void
+none_crypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
+{
+ memcpy(dest, src, len);
+}
+
+/* DES */
+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);
+}
+void
+des_ssh1_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
+{
+ memset(cc->u.des.iv, 0, sizeof(cc->u.des.iv));
+}
+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);
+}
+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 */
+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);
+}
+void
+des3_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
+{
+ 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);
+}
+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);
+}
+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);
+}
+
/*
* This is used by SSH1:
*
@@ -58,48 +135,84 @@ RCSID("$OpenBSD: cipher.c,v 1.31 2000/09/12 00:38:32 deraadt Exp $");
* 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)
+des3_ssh1_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);
+ if (keylen <= 16)
+ des_set_key((void *) key, cc->u.des3.key3);
+ else
+ des_set_key((void *) (key+16), cc->u.des3.key3);
+}
+void
+des3_ssh1_encrypt(CipherContext *cc, u_char *dest, const u_char *src,
+ u_int len)
{
des_cblock iv1;
+ des_cblock *iv2 = &cc->u.des3.iv2;
+ des_cblock *iv3 = &cc->u.des3.iv3;
memcpy(&iv1, iv2, 8);
- des_cbc_encrypt(src, dest, len, ks1, &iv1, DES_ENCRYPT);
+ des_cbc_encrypt(src, dest, len, cc->u.des3.key1, &iv1, DES_ENCRYPT);
memcpy(&iv1, dest + len - 8, 8);
- des_cbc_encrypt(dest, dest, len, ks2, iv2, DES_DECRYPT);
+ des_cbc_encrypt(dest, dest, len, cc->u.des3.key2, iv2, DES_DECRYPT);
memcpy(iv2, &iv1, 8); /* Note how iv1 == iv2 on entry and exit. */
- des_cbc_encrypt(dest, dest, len, ks3, iv3, DES_ENCRYPT);
+ des_cbc_encrypt(dest, dest, len, cc->u.des3.key3, iv3, DES_ENCRYPT);
memcpy(iv3, dest + len - 8, 8);
}
-
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)
+des3_ssh1_decrypt(CipherContext *cc, u_char *dest, const u_char *src,
+ u_int len)
{
des_cblock iv1;
+ des_cblock *iv2 = &cc->u.des3.iv2;
+ des_cblock *iv3 = &cc->u.des3.iv3;
memcpy(&iv1, iv2, 8);
- des_cbc_encrypt(src, dest, len, ks3, iv3, DES_DECRYPT);
+ des_cbc_encrypt(src, dest, len, cc->u.des3.key3, iv3, DES_DECRYPT);
memcpy(iv3, src + len - 8, 8);
- des_cbc_encrypt(dest, dest, len, ks2, iv2, DES_ENCRYPT);
+ des_cbc_encrypt(dest, dest, len, cc->u.des3.key2, iv2, DES_ENCRYPT);
memcpy(iv2, dest + len - 8, 8);
- des_cbc_encrypt(dest, dest, len, ks1, &iv1, DES_DECRYPT);
+ des_cbc_encrypt(dest, dest, len, cc->u.des3.key1, &iv1, DES_DECRYPT);
/* memcpy(&iv1, iv2, 8); */
/* Note how iv1 == iv2 on entry and exit. */
}
+/* Blowfish */
+void
+blowfish_setkey(CipherContext *cc, const u_char *key, u_int keylen)
+{
+ BF_set_key(&cc->u.bf.key, keylen, (unsigned char *)key);
+}
+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);
+}
+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);
+}
+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);
+}
+
/*
* SSH1 uses a variation on Blowfish, all bytes must be swapped before
* and after encryption/decryption. Thus the swap_bytes stuff (yuk).
@@ -130,88 +243,255 @@ swap_bytes(const unsigned char *src, unsigned char *dst_, int n)
}
}
-/*
- * Names of all encryption algorithms.
- * These must match the numbers defined in cipher.h.
- */
-static char *cipher_names[] =
-{
- "none",
- "idea",
- "des",
- "3des",
- "tss",
- "rc4", /* Alleged RC4 */
- "blowfish",
- "reserved",
- "blowfish-cbc",
- "3des-cbc",
- "arcfour",
- "cast128-cbc"
-};
+void
+blowfish_ssh1_encrypt(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_ENCRYPT);
+ swap_bytes(dest, dest, len);
+}
+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);
+}
-/*
- * Returns a bit mask indicating which ciphers are supported by this
- * implementation. The bit mask has the corresponding bit set of each
- * supported cipher.
- */
+/* alleged rc4 */
+void
+arcfour_setkey(CipherContext *cc, const u_char *key, u_int keylen)
+{
+ RC4_set_key(&cc->u.rc4, keylen, (u_char *)key);
+}
+void
+arcfour_crypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
+{
+ RC4(&cc->u.rc4, len, (u_char *)src, dest);
+}
-unsigned int
-cipher_mask1()
+/* CAST */
+void
+cast_setkey(CipherContext *cc, const u_char *key, u_int keylen)
{
- unsigned int mask = 0;
- mask |= 1 << SSH_CIPHER_3DES; /* Mandatory */
- mask |= 1 << SSH_CIPHER_BLOWFISH;
- return mask;
+ CAST_set_key(&cc->u.cast.key, keylen, (unsigned char *) key);
+}
+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);
+}
+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);
+}
+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);
+}
+
+/* RIJNDAEL */
+
+#define RIJNDAEL_BLOCKSIZE 16
+void
+rijndael_setkey(CipherContext *cc, const u_char *key, u_int keylen)
+{
+ rijndael_set_key(&cc->u.rijndael.enc, (u4byte *)key, 8*keylen, 1);
+ rijndael_set_key(&cc->u.rijndael.dec, (u4byte *)key, 8*keylen, 0);
+}
+void
+rijndael_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
+{
+ if (iv == NULL)
+ fatal("no IV for %s.", cc->cipher->name);
+ memcpy((u_char *)cc->u.rijndael.iv, iv, RIJNDAEL_BLOCKSIZE);
}
+void
+rijndael_cbc_encrypt(CipherContext *cc, u_char *dest, const u_char *src,
+ u_int len)
+{
+ rijndael_ctx *ctx = &cc->u.rijndael.enc;
+ u4byte *iv = cc->u.rijndael.iv;
+ u4byte in[4];
+ u4byte *cprev, *cnow, *plain;
+ int i, blocks = len / RIJNDAEL_BLOCKSIZE;
+ if (len == 0)
+ return;
+ if (len % RIJNDAEL_BLOCKSIZE)
+ fatal("rijndael_cbc_encrypt: bad len %d", len);
+ cnow = (u4byte*) dest;
+ plain = (u4byte*) src;
+ cprev = iv;
+ for(i = 0; i < blocks; i++, plain+=4, cnow+=4) {
+ in[0] = plain[0] ^ cprev[0];
+ in[1] = plain[1] ^ cprev[1];
+ in[2] = plain[2] ^ cprev[2];
+ in[3] = plain[3] ^ cprev[3];
+ rijndael_encrypt(ctx, in, cnow);
+ cprev = cnow;
+ }
+ memcpy(iv, cprev, RIJNDAEL_BLOCKSIZE);
+}
+
+void
+rijndael_cbc_decrypt(CipherContext *cc, u_char *dest, const u_char *src,
+ u_int len)
+{
+ rijndael_ctx *ctx = &cc->u.rijndael.dec;
+ u4byte *iv = cc->u.rijndael.iv;
+ u4byte ivsaved[4];
+ u4byte *cnow = (u4byte*) (src+len-RIJNDAEL_BLOCKSIZE);
+ u4byte *plain = (u4byte*) (dest+len-RIJNDAEL_BLOCKSIZE);
+ u4byte *ivp;
+ int i, 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-=4, plain-=4) {
+ rijndael_decrypt(ctx, cnow, plain);
+ ivp = (i == 1) ? iv : cnow-4;
+ plain[0] ^= ivp[0];
+ plain[1] ^= ivp[1];
+ plain[2] ^= ivp[2];
+ plain[3] ^= ivp[3];
+ }
+ memcpy(iv, ivsaved, RIJNDAEL_BLOCKSIZE);
+}
+
+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 }
+};
+
+/*--*/
+
unsigned int
-cipher_mask2()
+cipher_mask_ssh1(int client)
{
unsigned int mask = 0;
- mask |= 1 << SSH_CIPHER_BLOWFISH_CBC;
- mask |= 1 << SSH_CIPHER_3DES_CBC;
- mask |= 1 << SSH_CIPHER_ARCFOUR;
- mask |= 1 << SSH_CIPHER_CAST128_CBC;
+ mask |= 1 << SSH_CIPHER_3DES; /* Mandatory */
+ mask |= 1 << SSH_CIPHER_BLOWFISH;
+ if (client) {
+ mask |= 1 << SSH_CIPHER_DES;
+ }
return mask;
}
-unsigned int
-cipher_mask()
+
+Cipher *
+cipher_by_name(const char *name)
{
- return cipher_mask1() | cipher_mask2();
+ Cipher *c;
+ for (c = ciphers; c->name != NULL; c++)
+ if (strcasecmp(c->name, name) == 0)
+ return c;
+ return NULL;
}
-/* Returns the name of the cipher. */
-
-const char *
-cipher_name(int cipher)
+Cipher *
+cipher_by_number(int id)
{
- if (cipher < 0 || cipher >= sizeof(cipher_names) / sizeof(cipher_names[0]) ||
- cipher_names[cipher] == NULL)
- fatal("cipher_name: bad cipher name: %d", cipher);
- return cipher_names[cipher];
+ Cipher *c;
+ for (c = ciphers; c->name != NULL; c++)
+ if (c->number == id)
+ return c;
+ return NULL;
}
-/* Returns 1 if the name of the ciphers are valid. */
-
#define CIPHER_SEP ","
int
ciphers_valid(const char *names)
{
+ Cipher *c;
char *ciphers, *cp;
char *p;
- int i;
if (names == NULL || strcmp(names, "") == 0)
return 0;
ciphers = cp = xstrdup(names);
- for ((p = strsep(&cp, CIPHER_SEP)); p && *p != '\0';
+ for ((p = strsep(&cp, CIPHER_SEP)); p && *p != '\0';
(p = strsep(&cp, CIPHER_SEP))) {
- i = cipher_number(p);
- if (i == -1 || !(cipher_mask2() & (1 << i))) {
+ 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 {
+ debug("cipher ok: %s [%s]", p, names);
}
}
+ debug("ciphers ok: [%s]", names);
xfree(ciphers);
return 1;
}
@@ -224,14 +504,49 @@ ciphers_valid(const char *names)
int
cipher_number(const char *name)
{
- int i;
+ Cipher *c;
if (name == NULL)
return -1;
- 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;
+ 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);
}
/*
@@ -240,248 +555,18 @@ cipher_number(const char *name)
*/
void
-cipher_set_key_string(CipherContext *context, int cipher, const char *passphrase)
+cipher_set_key_string(CipherContext *cc, Cipher *cipher,
+ const char *passphrase)
{
MD5_CTX md;
unsigned 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);
+ 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)
-{
- 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:
- if (keylen < 16)
- error("Key length %d is insufficient for blowfish.", keylen);
- BF_set_key(&context->u.bf.key, keylen, padded);
- memset(context->u.bf.iv, 0, 8);
- break;
-
- case SSH_CIPHER_3DES_CBC:
- case SSH_CIPHER_BLOWFISH_CBC:
- case SSH_CIPHER_ARCFOUR:
- case SSH_CIPHER_CAST128_CBC:
- fatal("cipher_set_key: illegal cipher: %s", cipher_name(cipher));
- break;
-
- default:
- fatal("cipher_set_key: unknown cipher: %s", cipher_name(cipher));
- }
- memset(padded, 0, sizeof(padded));
-}
-
-void
-cipher_set_key_iv(CipherContext * context, int cipher,
- const unsigned char *key, int keylen,
- const unsigned char *iv, int ivlen)
-{
- /* Set cipher type. */
- context->type = cipher;
-
- /* Initialize the initialization vector. */
- switch (cipher) {
- case SSH_CIPHER_NONE:
- break;
-
- case SSH_CIPHER_3DES:
- case SSH_CIPHER_BLOWFISH:
- fatal("cipher_set_key_iv: illegal cipher: %s", cipher_name(cipher));
- break;
-
- case SSH_CIPHER_3DES_CBC:
- if (keylen < 24)
- error("Key length %d is insufficient for 3des-cbc.", keylen);
- des_set_key((void *) key, context->u.des3.key1);
- des_set_key((void *) (key+8), context->u.des3.key2);
- des_set_key((void *) (key+16), context->u.des3.key3);
- if (ivlen < 8)
- error("IV length %d is insufficient for 3des-cbc.", ivlen);
- memcpy(context->u.des3.iv3, (char *)iv, 8);
- break;
-
- case SSH_CIPHER_BLOWFISH_CBC:
- if (keylen < 16)
- error("Key length %d is insufficient for blowfish.", keylen);
- if (ivlen < 8)
- error("IV length %d is insufficient for blowfish.", ivlen);
- BF_set_key(&context->u.bf.key, keylen, (unsigned char *)key);
- memcpy(context->u.bf.iv, (char *)iv, 8);
- break;
-
- case SSH_CIPHER_ARCFOUR:
- if (keylen < 16)
- error("Key length %d is insufficient for arcfour.", keylen);
- RC4_set_key(&context->u.rc4, keylen, (unsigned char *)key);
- break;
-
- case SSH_CIPHER_CAST128_CBC:
- if (keylen < 16)
- error("Key length %d is insufficient for cast128.", keylen);
- if (ivlen < 8)
- error("IV length %d is insufficient for cast128.", ivlen);
- CAST_set_key(&context->u.cast.key, keylen, (unsigned char *) key);
- memcpy(context->u.cast.iv, (char *)iv, 8);
- break;
-
- default:
- fatal("cipher_set_key: unknown cipher: %s", cipher_name(cipher));
- }
-}
-
-/* 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;
-
- case SSH_CIPHER_BLOWFISH_CBC:
- BF_cbc_encrypt((void *)src, dest, len,
- &context->u.bf.key, context->u.bf.iv,
- BF_ENCRYPT);
- break;
-
- case SSH_CIPHER_3DES_CBC:
- des_ede3_cbc_encrypt(src, dest, len,
- context->u.des3.key1, context->u.des3.key2,
- context->u.des3.key3, &context->u.des3.iv3, DES_ENCRYPT);
- break;
-
- case SSH_CIPHER_ARCFOUR:
- RC4(&context->u.rc4, len, (unsigned char *)src, dest);
- break;
-
- case SSH_CIPHER_CAST128_CBC:
- CAST_cbc_encrypt(src, dest, len,
- &context->u.cast.key, context->u.cast.iv, CAST_ENCRYPT);
- 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;
-
- case SSH_CIPHER_BLOWFISH_CBC:
- BF_cbc_encrypt((void *) src, dest, len,
- &context->u.bf.key, context->u.bf.iv,
- BF_DECRYPT);
- break;
-
- case SSH_CIPHER_3DES_CBC:
- des_ede3_cbc_encrypt(src, dest, len,
- context->u.des3.key1, context->u.des3.key2,
- context->u.des3.key3, &context->u.des3.iv3, DES_DECRYPT);
- break;
-
- case SSH_CIPHER_ARCFOUR:
- RC4(&context->u.rc4, len, (unsigned char *)src, dest);
- break;
-
- case SSH_CIPHER_CAST128_CBC:
- CAST_cbc_encrypt(src, dest, len,
- &context->u.cast.key, context->u.cast.iv, CAST_DECRYPT);
- break;
-
- default:
- fatal("cipher_decrypt: unknown cipher: %s", cipher_name(context->type));
- }
-}