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_OPENSSL 24 25 #include <sys/types.h> 26 27 #include <stdarg.h> 28 #include <string.h> 29 30 #include <openssl/evp.h> 31 32 #include "openbsd-compat/openssl-compat.h" 33 34 /* 35 * SSH1 uses a variation on Blowfish, all bytes must be swapped before 36 * and after encryption/decryption. Thus the swap_bytes stuff (yuk). 37 */ 38 39 const EVP_CIPHER * evp_ssh1_bf(void); 40 41 static void 42 swap_bytes(const u_char *src, u_char *dst, int n) 43 { 44 u_char c[4]; 45 46 /* Process 4 bytes every lap. */ 47 for (n = n / 4; n > 0; n--) { 48 c[3] = *src++; 49 c[2] = *src++; 50 c[1] = *src++; 51 c[0] = *src++; 52 53 *dst++ = c[0]; 54 *dst++ = c[1]; 55 *dst++ = c[2]; 56 *dst++ = c[3]; 57 } 58 } 59 60 #ifdef SSH_OLD_EVP 61 static void bf_ssh1_init (EVP_CIPHER_CTX * ctx, const unsigned char *key, 62 const unsigned char *iv, int enc) 63 { 64 if (iv != NULL) 65 memcpy (&(ctx->oiv[0]), iv, 8); 66 memcpy (&(ctx->iv[0]), &(ctx->oiv[0]), 8); 67 if (key != NULL) 68 BF_set_key (&(ctx->c.bf_ks), EVP_CIPHER_CTX_key_length (ctx), 69 key); 70 } 71 #endif 72 73 static int (*orig_bf)(EVP_CIPHER_CTX *, u_char *, 74 const u_char *, LIBCRYPTO_EVP_INL_TYPE) = NULL; 75 76 static int 77 bf_ssh1_cipher(EVP_CIPHER_CTX *ctx, u_char *out, const u_char *in, 78 LIBCRYPTO_EVP_INL_TYPE len) 79 { 80 int ret; 81 82 swap_bytes(in, out, len); 83 ret = (*orig_bf)(ctx, out, out, len); 84 swap_bytes(out, out, len); 85 return (ret); 86 } 87 88 const EVP_CIPHER * 89 evp_ssh1_bf(void) 90 { 91 static EVP_CIPHER ssh1_bf; 92 93 memcpy(&ssh1_bf, EVP_bf_cbc(), sizeof(EVP_CIPHER)); 94 orig_bf = ssh1_bf.do_cipher; 95 ssh1_bf.nid = NID_undef; 96 #ifdef SSH_OLD_EVP 97 ssh1_bf.init = bf_ssh1_init; 98 #endif 99 ssh1_bf.do_cipher = bf_ssh1_cipher; 100 ssh1_bf.key_len = 32; 101 return (&ssh1_bf); 102 } 103 #endif /* WITH_OPENSSL */ 104