*/
#include "includes.h"
-RCSID("$OpenBSD: cipher.c,v 1.47 2001/08/23 11:31:59 markus Exp $");
+RCSID("$OpenBSD: cipher.c,v 1.52 2002/02/18 13:05:32 markus Exp $");
#include "xmalloc.h"
#include "log.h"
#include "cipher.h"
#include <openssl/md5.h>
+#include "rijndael.h"
+
+static EVP_CIPHER *evp_ssh1_3des(void);
+static EVP_CIPHER *evp_ssh1_bf(void);
+static EVP_CIPHER *evp_rijndael(void);
+
+struct Cipher {
+ char *name;
+ int number; /* for ssh1 only */
+ u_int block_size;
+ u_int key_len;
+ 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 },
+ { "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 },
+
+ { NULL, SSH_CIPHER_ILLEGAL, 0, 0, NULL }
+};
-/* 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);
-}
-
-/*
- * This is used by SSH1:
- *
- * What kind of triple DES are these 2 routines?
- *
- * Why is there a redundant initialization vector?
- *
- * If only iv3 was used, then, this would till effect have been
- * outer-cbc. However, there is also a private iv1 == iv2 which
- * perhaps makes differential analysis easier. On the other hand, the
- * private iv1 probably makes the CRC-32 attack ineffective. This is a
- * result of that there is no longer any known iv1 to use when
- * choosing the X block.
- */
-static void
-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);
-}
-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);
-}
-
-/* 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);
-}
-
-/*
- * 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];
- }
-}
-
-static 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);
-}
-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);
-}
-
-/* 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);
-}
-
-/* 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);
-}
-
-/* RIJNDAEL */
+/*--*/
-#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);
-}
-static void
-rijndael_cbc_encrypt(CipherContext *cc, u_char *dest, const u_char *src,
- u_int len)
+u_int
+cipher_blocksize(Cipher *c)
{
- 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);
+ return (c->block_size);
}
-static void
-rijndael_cbc_decrypt(CipherContext *cc, u_char *dest, const u_char *src,
- u_int len)
+u_int
+cipher_keylen(Cipher *c)
{
- 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);
+ return (c->key_len);
}
-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 }
-};
-
-/*--*/
-
u_int
cipher_mask_ssh1(int client)
{
u_int mask = 0;
- mask |= 1 << SSH_CIPHER_3DES; /* Mandatory */
+ mask |= 1 << SSH_CIPHER_3DES; /* Mandatory */
mask |= 1 << SSH_CIPHER_BLOWFISH;
if (client) {
mask |= 1 << SSH_CIPHER_DES;
return 0;
ciphers = cp = xstrdup(names);
for ((p = strsep(&cp, CIPHER_SEP)); p && *p != '\0';
- (p = strsep(&cp, CIPHER_SEP))) {
+ (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);
void
cipher_init(CipherContext *cc, Cipher *cipher,
- const u_char *key, u_int keylen, const u_char *iv, u_int ivlen)
+ const u_char *key, u_int keylen, const u_char *iv, u_int ivlen,
+ int encrypt)
{
+ static int dowarn = 1;
+ const EVP_CIPHER *type;
+ int klen;
+
+ if (cipher->number == SSH_CIPHER_DES) {
+ if (dowarn) {
+ error("Warning: use of DES is strongly discouraged "
+ "due to cryptographic weaknesses");
+ dowarn = 0;
+ }
+ if (keylen > 8)
+ keylen = 8;
+ }
+ cc->plaintext = (cipher->number == SSH_CIPHER_NONE);
+
if (keylen < cipher->key_len)
fatal("cipher_init: key length %d is insufficient for %s.",
keylen, cipher->name);
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);
+
+ type = (*cipher->evptype)();
+
+ EVP_CIPHER_CTX_init(&cc->evp);
+ if (EVP_CipherInit(&cc->evp, type, NULL, (u_char *)iv,
+ (encrypt == CIPHER_ENCRYPT)) == 0)
+ fatal("cipher_init: EVP_CipherInit failed for %s",
+ cipher->name);
+ klen = EVP_CIPHER_CTX_key_length(&cc->evp);
+ if (klen > 0 && keylen != klen) {
+ debug("cipher_init: set keylen (%d -> %d)", klen, keylen);
+ if (EVP_CIPHER_CTX_set_key_length(&cc->evp, keylen) == 0)
+ fatal("cipher_init: set keylen failed (%d -> %d)",
+ klen, keylen);
+ }
+ if (EVP_CipherInit(&cc->evp, NULL, (u_char *)key, NULL, -1) == 0)
+ fatal("cipher_init: EVP_CipherInit: set key failed for %s",
+ cipher->name);
}
void
-cipher_encrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
+cipher_crypt(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);
+ if (EVP_Cipher(&cc->evp, dest, (u_char *)src, len) == 0)
+ fatal("evp_crypt: EVP_Cipher failed");
}
void
-cipher_decrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
+cipher_cleanup(CipherContext *cc)
{
- if (len % cc->cipher->block_size)
- fatal("cipher_decrypt: bad ciphertext length %d", len);
- cc->cipher->decrypt(cc, dest, src, len);
+ if (EVP_CIPHER_CTX_cleanup(&cc->evp) == 0)
+ error("cipher_cleanup: EVP_CIPHER_CTX_cleanup failed");
}
/*
void
cipher_set_key_string(CipherContext *cc, Cipher *cipher,
- const char *passphrase)
+ const char *passphrase, int encrypt)
{
MD5_CTX md;
u_char digest[16];
MD5_Update(&md, (const u_char *)passphrase, strlen(passphrase));
MD5_Final(digest, &md);
- cipher_init(cc, cipher, digest, 16, NULL, 0);
+ cipher_init(cc, cipher, digest, 16, NULL, 0, encrypt);
memset(digest, 0, sizeof(digest));
memset(&md, 0, sizeof(md));
}
+
+/* Implementations for other non-EVP ciphers */
+
+/*
+ * This is used by SSH1:
+ *
+ * What kind of triple DES are these 2 routines?
+ *
+ * Why is there a redundant initialization vector?
+ *
+ * If only iv3 was used, then, this would till effect have been
+ * outer-cbc. However, there is also a private iv1 == iv2 which
+ * perhaps makes differential analysis easier. On the other hand, the
+ * private iv1 probably makes the CRC-32 attack ineffective. This is a
+ * result of that there is no longer any known iv1 to use when
+ * choosing the X block.
+ */
+struct ssh1_3des_ctx
+{
+ EVP_CIPHER_CTX k1, k2, k3;
+};
+static int
+ssh1_3des_init(EVP_CIPHER_CTX *ctx, const u_char *key, const u_char *iv,
+ int enc)
+{
+ struct ssh1_3des_ctx *c;
+ u_char *k1, *k2, *k3;
+
+ 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)
+ return (1);
+ if (enc == -1)
+ enc = ctx->encrypt;
+ k1 = k2 = k3 = (u_char *) key;
+ k2 += 8;
+ if (EVP_CIPHER_CTX_key_length(ctx) >= 16+8) {
+ if (enc)
+ k3 += 16;
+ else
+ k1 += 16;
+ }
+ EVP_CIPHER_CTX_init(&c->k1);
+ EVP_CIPHER_CTX_init(&c->k2);
+ EVP_CIPHER_CTX_init(&c->k3);
+ if (EVP_CipherInit(&c->k1, EVP_des_cbc(), k1, NULL, enc) == 0 ||
+ EVP_CipherInit(&c->k2, EVP_des_cbc(), k2, NULL, !enc) == 0 ||
+ EVP_CipherInit(&c->k3, EVP_des_cbc(), k3, NULL, enc) == 0) {
+ memset(c, 0, sizeof(*c));
+ xfree(c);
+ EVP_CIPHER_CTX_set_app_data(ctx, NULL);
+ return (0);
+ }
+ return (1);
+}
+static int
+ssh1_3des_cbc(EVP_CIPHER_CTX *ctx, u_char *dest, const u_char *src, u_int len)
+{
+ struct ssh1_3des_ctx *c;
+
+ if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) == NULL) {
+ error("ssh1_3des_cbc: no context");
+ return (0);
+ }
+ if (EVP_Cipher(&c->k1, dest, (u_char *)src, len) == 0 ||
+ EVP_Cipher(&c->k2, dest, dest, len) == 0 ||
+ EVP_Cipher(&c->k3, dest, dest, len) == 0)
+ return (0);
+ return (1);
+}
+static int
+ssh1_3des_cleanup(EVP_CIPHER_CTX *ctx)
+{
+ struct ssh1_3des_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);
+}
+static EVP_CIPHER *
+evp_ssh1_3des(void)
+{
+ static EVP_CIPHER ssh1_3des;
+
+ memset(&ssh1_3des, 0, sizeof(EVP_CIPHER));
+ ssh1_3des.nid = NID_undef;
+ ssh1_3des.block_size = 8;
+ ssh1_3des.iv_len = 0;
+ ssh1_3des.key_len = 16;
+ ssh1_3des.init = ssh1_3des_init;
+ ssh1_3des.cleanup = ssh1_3des_cleanup;
+ ssh1_3des.do_cipher = ssh1_3des_cbc;
+ ssh1_3des.flags = EVP_CIPH_CBC_MODE | EVP_CIPH_VARIABLE_LENGTH;
+ return (&ssh1_3des);
+}
+
+/*
+ * 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)
+{
+ u_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];
+ }
+}
+static int (*orig_bf)(EVP_CIPHER_CTX *, u_char *, const u_char *, u_int) = NULL;
+static int
+bf_ssh1_cipher(EVP_CIPHER_CTX *ctx, u_char *out, const u_char *in, u_int len)
+{
+ int ret;
+
+ swap_bytes(in, out, len);
+ ret = (*orig_bf)(ctx, out, out, len);
+ swap_bytes(out, out, len);
+ return (ret);
+}
+static EVP_CIPHER *
+evp_ssh1_bf(void)
+{
+ static EVP_CIPHER ssh1_bf;
+
+ memcpy(&ssh1_bf, EVP_bf_cbc(), sizeof(EVP_CIPHER));
+ orig_bf = ssh1_bf.do_cipher;
+ ssh1_bf.nid = NID_undef;
+ ssh1_bf.do_cipher = bf_ssh1_cipher;
+ ssh1_bf.key_len = 32;
+ return (&ssh1_bf);
+}
+
+/* RIJNDAEL */
+#define RIJNDAEL_BLOCKSIZE 16
+struct ssh_rijndael_ctx
+{
+ rijndael_ctx r_ctx;
+ u_char r_iv[RIJNDAEL_BLOCKSIZE];
+};
+
+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);
+}
+static 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;
+ rijndal_cbc.flags = EVP_CIPH_CBC_MODE | EVP_CIPH_VARIABLE_LENGTH |
+ EVP_CIPH_ALWAYS_CALL_INIT;
+ return (&rijndal_cbc);
+}
andersk / gssapi-openssh.git / blobdiff