version 1.37.2.5, 2001/09/27 00:15:41 |
version 1.37.2.6, 2002/03/08 17:04:42 |
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#include "log.h" |
#include "log.h" |
#include "cipher.h" |
#include "cipher.h" |
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#define EVP_CIPHER_CTX_get_app_data(e) ((e)->app_data) |
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#include <openssl/md5.h> |
#include <openssl/md5.h> |
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#include "rijndael.h" |
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/* no encryption */ |
static EVP_CIPHER *evp_ssh1_3des(void); |
static void |
static EVP_CIPHER *evp_ssh1_bf(void); |
none_setkey(CipherContext *cc, const u_char *key, u_int keylen) |
static EVP_CIPHER *evp_rijndael(void); |
{ |
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} |
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static void |
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none_setiv(CipherContext *cc, const u_char *iv, u_int ivlen) |
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{ |
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} |
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static void |
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none_crypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len) |
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{ |
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memcpy(dest, src, len); |
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} |
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/* DES */ |
struct Cipher { |
static void |
char *name; |
des_ssh1_setkey(CipherContext *cc, const u_char *key, u_int keylen) |
int number; /* for ssh1 only */ |
{ |
u_int block_size; |
static int dowarn = 1; |
u_int key_len; |
if (dowarn) { |
EVP_CIPHER *(*evptype)(void); |
error("Warning: use of DES is strongly discouraged " |
} ciphers[] = { |
"due to cryptographic weaknesses"); |
{ "none", SSH_CIPHER_NONE, 8, 0, EVP_enc_null }, |
dowarn = 0; |
{ "des", SSH_CIPHER_DES, 8, 8, EVP_des_cbc }, |
} |
{ "3des", SSH_CIPHER_3DES, 8, 16, evp_ssh1_3des }, |
des_set_key((void *)key, cc->u.des.key); |
{ "blowfish", SSH_CIPHER_BLOWFISH, 8, 32, evp_ssh1_bf }, |
} |
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static void |
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des_ssh1_setiv(CipherContext *cc, const u_char *iv, u_int ivlen) |
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{ |
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memset(cc->u.des.iv, 0, sizeof(cc->u.des.iv)); |
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} |
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static void |
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des_ssh1_encrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len) |
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{ |
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des_ncbc_encrypt(src, dest, len, cc->u.des.key, &cc->u.des.iv, |
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DES_ENCRYPT); |
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} |
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static void |
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des_ssh1_decrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len) |
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{ |
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des_ncbc_encrypt(src, dest, len, cc->u.des.key, &cc->u.des.iv, |
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DES_DECRYPT); |
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} |
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/* 3DES */ |
{ "3des-cbc", SSH_CIPHER_SSH2, 8, 24, EVP_des_ede3_cbc }, |
static void |
{ "blowfish-cbc", SSH_CIPHER_SSH2, 8, 16, EVP_bf_cbc }, |
des3_setkey(CipherContext *cc, const u_char *key, u_int keylen) |
{ "cast128-cbc", SSH_CIPHER_SSH2, 8, 16, EVP_cast5_cbc }, |
{ |
{ "arcfour", SSH_CIPHER_SSH2, 8, 16, EVP_rc4 }, |
des_set_key((void *) key, cc->u.des3.key1); |
{ "aes128-cbc", SSH_CIPHER_SSH2, 16, 16, evp_rijndael }, |
des_set_key((void *) (key+8), cc->u.des3.key2); |
{ "aes192-cbc", SSH_CIPHER_SSH2, 16, 24, evp_rijndael }, |
des_set_key((void *) (key+16), cc->u.des3.key3); |
{ "aes256-cbc", SSH_CIPHER_SSH2, 16, 32, evp_rijndael }, |
} |
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static void |
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des3_setiv(CipherContext *cc, const u_char *iv, u_int ivlen) |
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{ |
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memset(cc->u.des3.iv1, 0, sizeof(cc->u.des3.iv1)); |
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memset(cc->u.des3.iv2, 0, sizeof(cc->u.des3.iv2)); |
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memset(cc->u.des3.iv3, 0, sizeof(cc->u.des3.iv3)); |
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if (iv == NULL) |
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return; |
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memcpy(cc->u.des3.iv3, (char *)iv, 8); |
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} |
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static void |
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des3_cbc_encrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len) |
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{ |
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des_ede3_cbc_encrypt(src, dest, len, |
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cc->u.des3.key1, cc->u.des3.key2, cc->u.des3.key3, |
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&cc->u.des3.iv3, DES_ENCRYPT); |
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} |
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static void |
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des3_cbc_decrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len) |
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{ |
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des_ede3_cbc_encrypt(src, dest, len, |
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cc->u.des3.key1, cc->u.des3.key2, cc->u.des3.key3, |
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&cc->u.des3.iv3, DES_DECRYPT); |
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} |
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/* |
{ NULL, SSH_CIPHER_ILLEGAL, 0, 0, NULL } |
* This is used by SSH1: |
}; |
* |
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* What kind of triple DES are these 2 routines? |
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* |
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* Why is there a redundant initialization vector? |
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* |
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* If only iv3 was used, then, this would till effect have been |
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* outer-cbc. However, there is also a private iv1 == iv2 which |
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* perhaps makes differential analysis easier. On the other hand, the |
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* private iv1 probably makes the CRC-32 attack ineffective. This is a |
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* result of that there is no longer any known iv1 to use when |
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* choosing the X block. |
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*/ |
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static void |
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des3_ssh1_setkey(CipherContext *cc, const u_char *key, u_int keylen) |
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{ |
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des_set_key((void *) key, cc->u.des3.key1); |
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des_set_key((void *) (key+8), cc->u.des3.key2); |
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if (keylen <= 16) |
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des_set_key((void *) key, cc->u.des3.key3); |
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else |
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des_set_key((void *) (key+16), cc->u.des3.key3); |
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} |
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static void |
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des3_ssh1_encrypt(CipherContext *cc, u_char *dest, const u_char *src, |
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u_int len) |
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{ |
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des_ncbc_encrypt(src, dest, len, cc->u.des3.key1, &cc->u.des3.iv1, |
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DES_ENCRYPT); |
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des_ncbc_encrypt(dest, dest, len, cc->u.des3.key2, &cc->u.des3.iv2, |
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DES_DECRYPT); |
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des_ncbc_encrypt(dest, dest, len, cc->u.des3.key3, &cc->u.des3.iv3, |
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DES_ENCRYPT); |
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} |
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static void |
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des3_ssh1_decrypt(CipherContext *cc, u_char *dest, const u_char *src, |
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u_int len) |
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{ |
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des_ncbc_encrypt(src, dest, len, cc->u.des3.key3, &cc->u.des3.iv3, |
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DES_DECRYPT); |
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des_ncbc_encrypt(dest, dest, len, cc->u.des3.key2, &cc->u.des3.iv2, |
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DES_ENCRYPT); |
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des_ncbc_encrypt(dest, dest, len, cc->u.des3.key1, &cc->u.des3.iv1, |
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DES_DECRYPT); |
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} |
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/* Blowfish */ |
/*--*/ |
static void |
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blowfish_setkey(CipherContext *cc, const u_char *key, u_int keylen) |
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{ |
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BF_set_key(&cc->u.bf.key, keylen, (u_char *)key); |
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} |
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static void |
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blowfish_setiv(CipherContext *cc, const u_char *iv, u_int ivlen) |
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{ |
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if (iv == NULL) |
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memset(cc->u.bf.iv, 0, 8); |
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else |
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memcpy(cc->u.bf.iv, (char *)iv, 8); |
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} |
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static void |
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blowfish_cbc_encrypt(CipherContext *cc, u_char *dest, const u_char *src, |
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u_int len) |
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{ |
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BF_cbc_encrypt((void *)src, dest, len, &cc->u.bf.key, cc->u.bf.iv, |
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BF_ENCRYPT); |
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} |
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static void |
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blowfish_cbc_decrypt(CipherContext *cc, u_char *dest, const u_char *src, |
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u_int len) |
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{ |
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BF_cbc_encrypt((void *)src, dest, len, &cc->u.bf.key, cc->u.bf.iv, |
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BF_DECRYPT); |
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} |
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/* |
u_int |
* SSH1 uses a variation on Blowfish, all bytes must be swapped before |
cipher_blocksize(Cipher *c) |
* and after encryption/decryption. Thus the swap_bytes stuff (yuk). |
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*/ |
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static void |
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swap_bytes(const u_char *src, u_char *dst, int n) |
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{ |
{ |
char c[4]; |
return (c->block_size); |
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/* Process 4 bytes every lap. */ |
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for (n = n / 4; n > 0; n--) { |
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c[3] = *src++; |
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c[2] = *src++; |
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c[1] = *src++; |
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c[0] = *src++; |
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*dst++ = c[0]; |
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*dst++ = c[1]; |
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*dst++ = c[2]; |
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*dst++ = c[3]; |
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} |
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} |
} |
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u_int |
static void |
cipher_keylen(Cipher *c) |
blowfish_ssh1_encrypt(CipherContext *cc, u_char *dest, const u_char *src, |
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u_int len) |
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{ |
{ |
swap_bytes(src, dest, len); |
return (c->key_len); |
BF_cbc_encrypt((void *)dest, dest, len, &cc->u.bf.key, cc->u.bf.iv, |
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BF_ENCRYPT); |
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swap_bytes(dest, dest, len); |
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} |
} |
static void |
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blowfish_ssh1_decrypt(CipherContext *cc, u_char *dest, const u_char *src, |
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u_int len) |
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{ |
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swap_bytes(src, dest, len); |
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BF_cbc_encrypt((void *)dest, dest, len, &cc->u.bf.key, cc->u.bf.iv, |
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BF_DECRYPT); |
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swap_bytes(dest, dest, len); |
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} |
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/* alleged rc4 */ |
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static void |
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arcfour_setkey(CipherContext *cc, const u_char *key, u_int keylen) |
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{ |
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RC4_set_key(&cc->u.rc4, keylen, (u_char *)key); |
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} |
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static void |
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arcfour_crypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len) |
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{ |
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RC4(&cc->u.rc4, len, (u_char *)src, dest); |
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} |
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/* CAST */ |
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static void |
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cast_setkey(CipherContext *cc, const u_char *key, u_int keylen) |
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{ |
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CAST_set_key(&cc->u.cast.key, keylen, (u_char *) key); |
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} |
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static void |
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cast_setiv(CipherContext *cc, const u_char *iv, u_int ivlen) |
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{ |
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if (iv == NULL) |
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fatal("no IV for %s.", cc->cipher->name); |
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memcpy(cc->u.cast.iv, (char *)iv, 8); |
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} |
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static void |
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cast_cbc_encrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len) |
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{ |
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CAST_cbc_encrypt(src, dest, len, &cc->u.cast.key, cc->u.cast.iv, |
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CAST_ENCRYPT); |
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} |
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static void |
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cast_cbc_decrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len) |
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{ |
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CAST_cbc_encrypt(src, dest, len, &cc->u.cast.key, cc->u.cast.iv, |
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CAST_DECRYPT); |
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} |
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/* RIJNDAEL */ |
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#define RIJNDAEL_BLOCKSIZE 16 |
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static void |
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rijndael_setkey(CipherContext *cc, const u_char *key, u_int keylen) |
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{ |
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rijndael_set_key(&cc->u.rijndael.enc, (char *)key, 8*keylen, 1); |
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rijndael_set_key(&cc->u.rijndael.dec, (char *)key, 8*keylen, 0); |
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} |
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static void |
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rijndael_setiv(CipherContext *cc, const u_char *iv, u_int ivlen) |
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{ |
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if (iv == NULL || ivlen != RIJNDAEL_BLOCKSIZE) |
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fatal("bad/no IV for %s.", cc->cipher->name); |
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memcpy(cc->u.rijndael.iv, iv, RIJNDAEL_BLOCKSIZE); |
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} |
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static void |
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rijndael_cbc_encrypt(CipherContext *cc, u_char *dest, const u_char *src, |
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u_int len) |
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{ |
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rijndael_ctx *ctx = &cc->u.rijndael.enc; |
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u_char *iv = cc->u.rijndael.iv; |
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u_char in[RIJNDAEL_BLOCKSIZE]; |
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u_char *cprev, *cnow, *plain; |
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int i, j, blocks = len / RIJNDAEL_BLOCKSIZE; |
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if (len == 0) |
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return; |
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if (len % RIJNDAEL_BLOCKSIZE) |
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fatal("rijndael_cbc_encrypt: bad len %d", len); |
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cnow = dest; |
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plain = (u_char *) src; |
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cprev = iv; |
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for (i = 0; i < blocks; i++, plain+=RIJNDAEL_BLOCKSIZE, |
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cnow+=RIJNDAEL_BLOCKSIZE) { |
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for (j = 0; j < RIJNDAEL_BLOCKSIZE; j++) |
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in[j] = plain[j] ^ cprev[j]; |
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rijndael_encrypt(ctx, in, cnow); |
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cprev = cnow; |
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} |
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memcpy(iv, cprev, RIJNDAEL_BLOCKSIZE); |
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} |
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static void |
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rijndael_cbc_decrypt(CipherContext *cc, u_char *dest, const u_char *src, |
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u_int len) |
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{ |
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rijndael_ctx *ctx = &cc->u.rijndael.dec; |
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u_char *iv = cc->u.rijndael.iv; |
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u_char ivsaved[RIJNDAEL_BLOCKSIZE]; |
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u_char *cnow = (u_char *) (src+len-RIJNDAEL_BLOCKSIZE); |
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u_char *plain = dest+len-RIJNDAEL_BLOCKSIZE; |
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u_char *ivp; |
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int i, j, blocks = len / RIJNDAEL_BLOCKSIZE; |
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if (len == 0) |
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return; |
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if (len % RIJNDAEL_BLOCKSIZE) |
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fatal("rijndael_cbc_decrypt: bad len %d", len); |
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memcpy(ivsaved, cnow, RIJNDAEL_BLOCKSIZE); |
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for (i = blocks; i > 0; i--, cnow-=RIJNDAEL_BLOCKSIZE, |
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plain-=RIJNDAEL_BLOCKSIZE) { |
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rijndael_decrypt(ctx, cnow, plain); |
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ivp = (i == 1) ? iv : cnow-RIJNDAEL_BLOCKSIZE; |
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for (j = 0; j < RIJNDAEL_BLOCKSIZE; j++) |
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plain[j] ^= ivp[j]; |
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} |
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memcpy(iv, ivsaved, RIJNDAEL_BLOCKSIZE); |
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} |
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Cipher ciphers[] = { |
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{ "none", |
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SSH_CIPHER_NONE, 8, 0, |
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none_setkey, none_setiv, |
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none_crypt, none_crypt }, |
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{ "des", |
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SSH_CIPHER_DES, 8, 8, |
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des_ssh1_setkey, des_ssh1_setiv, |
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des_ssh1_encrypt, des_ssh1_decrypt }, |
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{ "3des", |
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SSH_CIPHER_3DES, 8, 16, |
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des3_ssh1_setkey, des3_setiv, |
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des3_ssh1_encrypt, des3_ssh1_decrypt }, |
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{ "blowfish", |
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SSH_CIPHER_BLOWFISH, 8, 16, |
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blowfish_setkey, blowfish_setiv, |
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blowfish_ssh1_encrypt, blowfish_ssh1_decrypt }, |
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{ "3des-cbc", |
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SSH_CIPHER_SSH2, 8, 24, |
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des3_setkey, des3_setiv, |
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des3_cbc_encrypt, des3_cbc_decrypt }, |
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{ "blowfish-cbc", |
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SSH_CIPHER_SSH2, 8, 16, |
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blowfish_setkey, blowfish_setiv, |
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blowfish_cbc_encrypt, blowfish_cbc_decrypt }, |
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{ "cast128-cbc", |
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SSH_CIPHER_SSH2, 8, 16, |
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cast_setkey, cast_setiv, |
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cast_cbc_encrypt, cast_cbc_decrypt }, |
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{ "arcfour", |
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SSH_CIPHER_SSH2, 8, 16, |
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arcfour_setkey, none_setiv, |
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arcfour_crypt, arcfour_crypt }, |
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{ "aes128-cbc", |
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SSH_CIPHER_SSH2, 16, 16, |
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rijndael_setkey, rijndael_setiv, |
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rijndael_cbc_encrypt, rijndael_cbc_decrypt }, |
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{ "aes192-cbc", |
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SSH_CIPHER_SSH2, 16, 24, |
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rijndael_setkey, rijndael_setiv, |
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rijndael_cbc_encrypt, rijndael_cbc_decrypt }, |
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{ "aes256-cbc", |
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SSH_CIPHER_SSH2, 16, 32, |
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rijndael_setkey, rijndael_setiv, |
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rijndael_cbc_encrypt, rijndael_cbc_decrypt }, |
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{ "rijndael128-cbc", |
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SSH_CIPHER_SSH2, 16, 16, |
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rijndael_setkey, rijndael_setiv, |
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rijndael_cbc_encrypt, rijndael_cbc_decrypt }, |
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{ "rijndael192-cbc", |
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SSH_CIPHER_SSH2, 16, 24, |
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rijndael_setkey, rijndael_setiv, |
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rijndael_cbc_encrypt, rijndael_cbc_decrypt }, |
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{ "rijndael256-cbc", |
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SSH_CIPHER_SSH2, 16, 32, |
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rijndael_setkey, rijndael_setiv, |
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rijndael_cbc_encrypt, rijndael_cbc_decrypt }, |
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{ "rijndael-cbc@lysator.liu.se", |
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SSH_CIPHER_SSH2, 16, 32, |
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rijndael_setkey, rijndael_setiv, |
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rijndael_cbc_encrypt, rijndael_cbc_decrypt }, |
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{ NULL, SSH_CIPHER_ILLEGAL, 0, 0, NULL, NULL, NULL, NULL } |
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}; |
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/*--*/ |
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u_int |
u_int |
cipher_mask_ssh1(int client) |
cipher_mask_ssh1(int client) |
{ |
{ |
u_int mask = 0; |
u_int mask = 0; |
mask |= 1 << SSH_CIPHER_3DES; /* Mandatory */ |
mask |= 1 << SSH_CIPHER_3DES; /* Mandatory */ |
mask |= 1 << SSH_CIPHER_BLOWFISH; |
mask |= 1 << SSH_CIPHER_BLOWFISH; |
if (client) { |
if (client) { |
mask |= 1 << SSH_CIPHER_DES; |
mask |= 1 << SSH_CIPHER_DES; |
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return 0; |
return 0; |
ciphers = cp = xstrdup(names); |
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))) { |
(p = strsep(&cp, CIPHER_SEP))) { |
c = cipher_by_name(p); |
c = cipher_by_name(p); |
if (c == NULL || c->number != SSH_CIPHER_SSH2) { |
if (c == NULL || c->number != SSH_CIPHER_SSH2) { |
debug("bad cipher %s [%s]", p, names); |
debug("bad cipher %s [%s]", p, names); |
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void |
void |
cipher_init(CipherContext *cc, Cipher *cipher, |
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, |
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int encrypt) |
{ |
{ |
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static int dowarn = 1; |
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const EVP_CIPHER *type; |
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int klen; |
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|
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if (cipher->number == SSH_CIPHER_DES) { |
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if (dowarn) { |
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error("Warning: use of DES is strongly discouraged " |
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"due to cryptographic weaknesses"); |
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dowarn = 0; |
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} |
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if (keylen > 8) |
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keylen = 8; |
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} |
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cc->plaintext = (cipher->number == SSH_CIPHER_NONE); |
|
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if (keylen < cipher->key_len) |
if (keylen < cipher->key_len) |
fatal("cipher_init: key length %d is insufficient for %s.", |
fatal("cipher_init: key length %d is insufficient for %s.", |
keylen, cipher->name); |
keylen, cipher->name); |
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fatal("cipher_init: iv length %d is insufficient for %s.", |
fatal("cipher_init: iv length %d is insufficient for %s.", |
ivlen, cipher->name); |
ivlen, cipher->name); |
cc->cipher = cipher; |
cc->cipher = cipher; |
cipher->setkey(cc, key, keylen); |
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cipher->setiv(cc, iv, ivlen); |
type = (*cipher->evptype)(); |
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|
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EVP_CIPHER_CTX_init(&cc->evp); |
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EVP_CipherInit(&cc->evp, type, (u_char *)key, (u_char *)iv, |
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(encrypt == CIPHER_ENCRYPT)); |
} |
} |
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void |
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) |
if (len % cc->cipher->block_size) |
fatal("cipher_encrypt: bad plaintext length %d", len); |
fatal("cipher_encrypt: bad plaintext length %d", len); |
cc->cipher->encrypt(cc, dest, src, len); |
EVP_Cipher(&cc->evp, dest, (u_char *)src, len); |
} |
} |
|
|
void |
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) |
EVP_CIPHER_CTX_cleanup(&cc->evp); |
fatal("cipher_decrypt: bad ciphertext length %d", len); |
|
cc->cipher->decrypt(cc, dest, src, len); |
|
} |
} |
|
|
/* |
/* |
|
|
|
|
void |
void |
cipher_set_key_string(CipherContext *cc, Cipher *cipher, |
cipher_set_key_string(CipherContext *cc, Cipher *cipher, |
const char *passphrase) |
const char *passphrase, int encrypt) |
{ |
{ |
MD5_CTX md; |
MD5_CTX md; |
u_char digest[16]; |
u_char digest[16]; |
|
|
MD5_Update(&md, (const u_char *)passphrase, strlen(passphrase)); |
MD5_Update(&md, (const u_char *)passphrase, strlen(passphrase)); |
MD5_Final(digest, &md); |
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(digest, 0, sizeof(digest)); |
memset(&md, 0, sizeof(md)); |
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); |
|
EVP_CipherInit(&c->k1, EVP_des_cbc(), k1, NULL, enc); |
|
EVP_CipherInit(&c->k2, EVP_des_cbc(), k2, NULL, !enc); |
|
EVP_CipherInit(&c->k3, EVP_des_cbc(), k3, NULL, enc); |
|
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); |
|
} |
|
EVP_Cipher(&c->k1, dest, (u_char *)src, len); |
|
EVP_Cipher(&c->k2, dest, dest, len); |
|
EVP_Cipher(&c->k3, dest, dest, len); |
|
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; |
|
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; |
|
return (&rijndal_cbc); |
} |
} |