1/* $OpenBSD: cipher-bf1.c,v 1.6 2010/10/01 23:05:32 djm Exp $ */ 2/* 3 * Copyright (c) 2003 Markus Friedl. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26#include "includes.h" 27 28#include <sys/types.h> 29 30#ifdef __APPLE_CRYPTO__ 31#include "ossl-evp.h" 32#else 33#include <openssl/evp.h> 34#endif 35 36#include <stdarg.h> 37#include <string.h> 38 39#include "xmalloc.h" 40#include "log.h" 41 42#include "openbsd-compat/openssl-compat.h" 43 44/* 45 * SSH1 uses a variation on Blowfish, all bytes must be swapped before 46 * and after encryption/decryption. Thus the swap_bytes stuff (yuk). 47 */ 48 49const EVP_CIPHER * evp_ssh1_bf(void); 50 51static void 52swap_bytes(const u_char *src, u_char *dst, int n) 53{ 54 u_char c[4]; 55 56 /* Process 4 bytes every lap. */ 57 for (n = n / 4; n > 0; n--) { 58 c[3] = *src++; 59 c[2] = *src++; 60 c[1] = *src++; 61 c[0] = *src++; 62 63 *dst++ = c[0]; 64 *dst++ = c[1]; 65 *dst++ = c[2]; 66 *dst++ = c[3]; 67 } 68} 69 70#ifdef SSH_OLD_EVP 71static void bf_ssh1_init (EVP_CIPHER_CTX * ctx, const unsigned char *key, 72 const unsigned char *iv, int enc) 73{ 74 if (iv != NULL) 75 memcpy (&(ctx->oiv[0]), iv, 8); 76 memcpy (&(ctx->iv[0]), &(ctx->oiv[0]), 8); 77 if (key != NULL) 78 BF_set_key (&(ctx->c.bf_ks), EVP_CIPHER_CTX_key_length (ctx), 79 key); 80} 81#endif 82 83static int (*orig_bf)(EVP_CIPHER_CTX *, u_char *, 84 const u_char *, LIBCRYPTO_EVP_INL_TYPE) = NULL; 85 86static int 87bf_ssh1_cipher(EVP_CIPHER_CTX *ctx, u_char *out, const u_char *in, 88 LIBCRYPTO_EVP_INL_TYPE len) 89{ 90 int ret; 91 92 swap_bytes(in, out, len); 93 ret = (*orig_bf)(ctx, out, out, len); 94 swap_bytes(out, out, len); 95 return (ret); 96} 97 98const EVP_CIPHER * 99evp_ssh1_bf(void) 100{ 101 static EVP_CIPHER ssh1_bf; 102 103 memcpy(&ssh1_bf, EVP_bf_cbc(), sizeof(EVP_CIPHER)); 104 orig_bf = ssh1_bf.do_cipher; 105 ssh1_bf.nid = NID_undef; 106#ifdef SSH_OLD_EVP 107 ssh1_bf.init = bf_ssh1_init; 108#endif 109 ssh1_bf.do_cipher = bf_ssh1_cipher; 110 ssh1_bf.key_len = 32; 111 return (&ssh1_bf); 112} 113