cipher-bf1.c revision 323134
1/* $OpenBSD: cipher-bf1.c,v 1.7 2015/01/14 10:24:42 markus Exp $ */ 2/* 3 * Copyright (c) 2003 Markus Friedl. All rights reserved. 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 10 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 11 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 12 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 13 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 14 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 15 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 16 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 17 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 18 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 19 */ 20 21#include "includes.h" 22 23#ifdef WITH_SSH1 24#if defined(WITH_OPENSSL) && !defined(OPENSSL_NO_BF) 25 26#include <sys/types.h> 27 28#include <stdarg.h> 29#include <string.h> 30 31#include <openssl/evp.h> 32 33#include "openbsd-compat/openssl-compat.h" 34 35/* 36 * SSH1 uses a variation on Blowfish, all bytes must be swapped before 37 * and after encryption/decryption. Thus the swap_bytes stuff (yuk). 38 */ 39 40const EVP_CIPHER * evp_ssh1_bf(void); 41 42static void 43swap_bytes(const u_char *src, u_char *dst, int n) 44{ 45 u_char c[4]; 46 47 /* Process 4 bytes every lap. */ 48 for (n = n / 4; n > 0; n--) { 49 c[3] = *src++; 50 c[2] = *src++; 51 c[1] = *src++; 52 c[0] = *src++; 53 54 *dst++ = c[0]; 55 *dst++ = c[1]; 56 *dst++ = c[2]; 57 *dst++ = c[3]; 58 } 59} 60 61#ifdef SSH_OLD_EVP 62static void bf_ssh1_init (EVP_CIPHER_CTX * ctx, const unsigned char *key, 63 const unsigned char *iv, int enc) 64{ 65 if (iv != NULL) 66 memcpy (&(ctx->oiv[0]), iv, 8); 67 memcpy (&(ctx->iv[0]), &(ctx->oiv[0]), 8); 68 if (key != NULL) 69 BF_set_key (&(ctx->c.bf_ks), EVP_CIPHER_CTX_key_length (ctx), 70 key); 71} 72#endif 73 74static int (*orig_bf)(EVP_CIPHER_CTX *, u_char *, 75 const u_char *, LIBCRYPTO_EVP_INL_TYPE) = NULL; 76 77static int 78bf_ssh1_cipher(EVP_CIPHER_CTX *ctx, u_char *out, const u_char *in, 79 LIBCRYPTO_EVP_INL_TYPE len) 80{ 81 int ret; 82 83 swap_bytes(in, out, len); 84 ret = (*orig_bf)(ctx, out, out, len); 85 swap_bytes(out, out, len); 86 return (ret); 87} 88 89const EVP_CIPHER * 90evp_ssh1_bf(void) 91{ 92 static EVP_CIPHER ssh1_bf; 93 94 memcpy(&ssh1_bf, EVP_bf_cbc(), sizeof(EVP_CIPHER)); 95 orig_bf = ssh1_bf.do_cipher; 96 ssh1_bf.nid = NID_undef; 97#ifdef SSH_OLD_EVP 98 ssh1_bf.init = bf_ssh1_init; 99#endif 100 ssh1_bf.do_cipher = bf_ssh1_cipher; 101 ssh1_bf.key_len = 32; 102 return (&ssh1_bf); 103} 104#endif /* defined(WITH_OPENSSL) && !defined(OPENSSL_NO_BF) */ 105 106#endif /* WITH_SSH1 */ 107