diff options
Diffstat (limited to 'crypto/openssh/cipher.c')
| -rw-r--r-- | crypto/openssh/cipher.c | 464 |
1 files changed, 0 insertions, 464 deletions
diff --git a/crypto/openssh/cipher.c b/crypto/openssh/cipher.c deleted file mode 100644 index 0f0f0d071a1ab..0000000000000 --- a/crypto/openssh/cipher.c +++ /dev/null @@ -1,464 +0,0 @@ -/* - * - * 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 - * - * $FreeBSD$ - */ - -#include "includes.h" -RCSID("$Id: cipher.c,v 1.27 2000/05/22 18:42:00 markus Exp $"); - -#include "ssh.h" -#include "cipher.h" -#include "xmalloc.h" - -#include <openssl/md5.h> - -/* - * 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. - */ -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) -{ - des_cblock iv1; - - memcpy(&iv1, iv2, 8); - - des_cbc_encrypt(src, dest, len, ks1, &iv1, DES_ENCRYPT); - memcpy(&iv1, dest + len - 8, 8); - - des_cbc_encrypt(dest, dest, len, ks2, 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); - 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) -{ - des_cblock iv1; - - memcpy(&iv1, iv2, 8); - - des_cbc_encrypt(src, dest, len, ks3, iv3, DES_DECRYPT); - memcpy(iv3, src + len - 8, 8); - - des_cbc_encrypt(dest, dest, len, ks2, iv2, DES_ENCRYPT); - memcpy(iv2, dest + len - 8, 8); - - des_cbc_encrypt(dest, dest, len, ks1, &iv1, DES_DECRYPT); - /* memcpy(&iv1, iv2, 8); */ - /* Note how iv1 == iv2 on entry and exit. */ -} - -/* - * 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 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; - } -} - -/* - * 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", - "reserved", - "blowfish-cbc", - "3des-cbc", - "arcfour", - "cast128-cbc" -}; - -/* - * 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_mask1() -{ - unsigned int mask = 0; - mask |= 1 << SSH_CIPHER_3DES; /* Mandatory */ - mask |= 1 << SSH_CIPHER_BLOWFISH; - return mask; -} -unsigned int -cipher_mask2() -{ - 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; - return mask; -} -unsigned int -cipher_mask() -{ - return cipher_mask1() | cipher_mask2(); -} - -/* Returns the name of the cipher. */ - -const char * -cipher_name(int cipher) -{ - 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]; -} - -/* Returns 1 if the name of the ciphers are valid. */ - -#define CIPHER_SEP "," -int -ciphers_valid(const char *names) -{ - char *ciphers; - char *p; - int i; - - if (names == NULL || strcmp(names, "") == 0) - return 0; - ciphers = xstrdup(names); - for ((p = strtok(ciphers, CIPHER_SEP)); p; (p = strtok(NULL, CIPHER_SEP))) { - i = cipher_number(p); - if (i == -1 || !(cipher_mask2() & (1 << i))) { - xfree(ciphers); - return 0; - } - } - xfree(ciphers); - return 1; -} - -/* - * Parses the name of the cipher. Returns the number of the corresponding - * cipher, or -1 on error. - */ - -int -cipher_number(const char *name) -{ - int i; - 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; -} - -/* - * Selects the cipher, and keys if by computing the MD5 checksum of the - * passphrase and using the resulting 16 bytes as the key. - */ - -void -cipher_set_key_string(CipherContext *context, int cipher, const char *passphrase) -{ - MD5_CTX md; - unsigned char digest[16]; - - MD5_Init(&md); - MD5_Update(&md, (const unsigned char *) passphrase, strlen(passphrase)); - MD5_Final(digest, &md); - - cipher_set_key(context, cipher, digest, 16); - - 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)); - } -} |