s2_enc.c revision 280304
1/* ssl/s2_enc.c */ 2/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay@cryptsoft.com). 7 * The implementation was written so as to conform with Netscapes SSL. 8 * 9 * This library is free for commercial and non-commercial use as long as 10 * the following conditions are aheared to. The following conditions 11 * apply to all code found in this distribution, be it the RC4, RSA, 12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 13 * included with this distribution is covered by the same copyright terms 14 * except that the holder is Tim Hudson (tjh@cryptsoft.com). 15 * 16 * Copyright remains Eric Young's, and as such any Copyright notices in 17 * the code are not to be removed. 18 * If this package is used in a product, Eric Young should be given attribution 19 * as the author of the parts of the library used. 20 * This can be in the form of a textual message at program startup or 21 * in documentation (online or textual) provided with the package. 22 * 23 * Redistribution and use in source and binary forms, with or without 24 * modification, are permitted provided that the following conditions 25 * are met: 26 * 1. Redistributions of source code must retain the copyright 27 * notice, this list of conditions and the following disclaimer. 28 * 2. Redistributions in binary form must reproduce the above copyright 29 * notice, this list of conditions and the following disclaimer in the 30 * documentation and/or other materials provided with the distribution. 31 * 3. All advertising materials mentioning features or use of this software 32 * must display the following acknowledgement: 33 * "This product includes cryptographic software written by 34 * Eric Young (eay@cryptsoft.com)" 35 * The word 'cryptographic' can be left out if the rouines from the library 36 * being used are not cryptographic related :-). 37 * 4. If you include any Windows specific code (or a derivative thereof) from 38 * the apps directory (application code) you must include an acknowledgement: 39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 40 * 41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 51 * SUCH DAMAGE. 52 * 53 * The licence and distribution terms for any publically available version or 54 * derivative of this code cannot be changed. i.e. this code cannot simply be 55 * copied and put under another distribution licence 56 * [including the GNU Public Licence.] 57 */ 58 59#include "ssl_locl.h" 60#ifndef OPENSSL_NO_SSL2 61# include <stdio.h> 62 63int ssl2_enc_init(SSL *s, int client) 64{ 65 /* Max number of bytes needed */ 66 EVP_CIPHER_CTX *rs, *ws; 67 const EVP_CIPHER *c; 68 const EVP_MD *md; 69 int num; 70 71 if (!ssl_cipher_get_evp(s->session, &c, &md, NULL, NULL, NULL)) { 72 ssl2_return_error(s, SSL2_PE_NO_CIPHER); 73 SSLerr(SSL_F_SSL2_ENC_INIT, SSL_R_PROBLEMS_MAPPING_CIPHER_FUNCTIONS); 74 return (0); 75 } 76 ssl_replace_hash(&s->read_hash, md); 77 ssl_replace_hash(&s->write_hash, md); 78 79 if ((s->enc_read_ctx == NULL) && ((s->enc_read_ctx = (EVP_CIPHER_CTX *) 80 OPENSSL_malloc(sizeof(EVP_CIPHER_CTX))) 81 == NULL)) 82 goto err; 83 84 /* 85 * make sure it's intialized in case the malloc for enc_write_ctx fails 86 * and we exit with an error 87 */ 88 rs = s->enc_read_ctx; 89 EVP_CIPHER_CTX_init(rs); 90 91 if ((s->enc_write_ctx == NULL) && ((s->enc_write_ctx = (EVP_CIPHER_CTX *) 92 OPENSSL_malloc(sizeof 93 (EVP_CIPHER_CTX))) == 94 NULL)) 95 goto err; 96 97 ws = s->enc_write_ctx; 98 EVP_CIPHER_CTX_init(ws); 99 100 num = c->key_len; 101 s->s2->key_material_length = num * 2; 102 OPENSSL_assert(s->s2->key_material_length <= sizeof s->s2->key_material); 103 104 if (ssl2_generate_key_material(s) <= 0) 105 return 0; 106 107 OPENSSL_assert(c->iv_len <= (int)sizeof(s->session->key_arg)); 108 EVP_EncryptInit_ex(ws, c, NULL, 109 &(s->s2->key_material[(client) ? num : 0]), 110 s->session->key_arg); 111 EVP_DecryptInit_ex(rs, c, NULL, 112 &(s->s2->key_material[(client) ? 0 : num]), 113 s->session->key_arg); 114 s->s2->read_key = &(s->s2->key_material[(client) ? 0 : num]); 115 s->s2->write_key = &(s->s2->key_material[(client) ? num : 0]); 116 return (1); 117 err: 118 SSLerr(SSL_F_SSL2_ENC_INIT, ERR_R_MALLOC_FAILURE); 119 return (0); 120} 121 122/* 123 * read/writes from s->s2->mac_data using length for encrypt and decrypt. 124 * It sets s->s2->padding and s->[rw]length if we are encrypting Returns 0 on 125 * error and 1 on success 126 */ 127int ssl2_enc(SSL *s, int send) 128{ 129 EVP_CIPHER_CTX *ds; 130 unsigned long l; 131 int bs; 132 133 if (send) { 134 ds = s->enc_write_ctx; 135 l = s->s2->wlength; 136 } else { 137 ds = s->enc_read_ctx; 138 l = s->s2->rlength; 139 } 140 141 /* check for NULL cipher */ 142 if (ds == NULL) 143 return 1; 144 145 bs = ds->cipher->block_size; 146 /* 147 * This should be using (bs-1) and bs instead of 7 and 8, but what the 148 * hell. 149 */ 150 if (bs == 8) 151 l = (l + 7) / 8 * 8; 152 153 if (EVP_Cipher(ds, s->s2->mac_data, s->s2->mac_data, l) < 1) 154 return 0; 155 156 return 1; 157} 158 159void ssl2_mac(SSL *s, unsigned char *md, int send) 160{ 161 EVP_MD_CTX c; 162 unsigned char sequence[4], *p, *sec, *act; 163 unsigned long seq; 164 unsigned int len; 165 166 if (send) { 167 seq = s->s2->write_sequence; 168 sec = s->s2->write_key; 169 len = s->s2->wact_data_length; 170 act = s->s2->wact_data; 171 } else { 172 seq = s->s2->read_sequence; 173 sec = s->s2->read_key; 174 len = s->s2->ract_data_length; 175 act = s->s2->ract_data; 176 } 177 178 p = &(sequence[0]); 179 l2n(seq, p); 180 181 /* There has to be a MAC algorithm. */ 182 EVP_MD_CTX_init(&c); 183 EVP_MD_CTX_copy(&c, s->read_hash); 184 EVP_DigestUpdate(&c, sec, EVP_CIPHER_CTX_key_length(s->enc_read_ctx)); 185 EVP_DigestUpdate(&c, act, len); 186 /* the above line also does the pad data */ 187 EVP_DigestUpdate(&c, sequence, 4); 188 EVP_DigestFinal_ex(&c, md, NULL); 189 EVP_MD_CTX_cleanup(&c); 190} 191#else /* !OPENSSL_NO_SSL2 */ 192 193# if PEDANTIC 194static void *dummy = &dummy; 195# endif 196 197#endif 198