1 /* $OpenBSD: bio_md.c,v 1.18 2022/01/14 08:40:57 tb Exp $ */ 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 <stdio.h> 60 #include <errno.h> 61 62 #include <openssl/buffer.h> 63 #include <openssl/evp.h> 64 65 #include "bio_local.h" 66 #include "evp_locl.h" 67 68 /* BIO_put and BIO_get both add to the digest, 69 * BIO_gets returns the digest */ 70 71 static int md_write(BIO *h, char const *buf, int num); 72 static int md_read(BIO *h, char *buf, int size); 73 /*static int md_puts(BIO *h, const char *str); */ 74 static int md_gets(BIO *h, char *str, int size); 75 static long md_ctrl(BIO *h, int cmd, long arg1, void *arg2); 76 static int md_new(BIO *h); 77 static int md_free(BIO *data); 78 static long md_callback_ctrl(BIO *h, int cmd, BIO_info_cb *fp); 79 80 static const BIO_METHOD methods_md = { 81 .type = BIO_TYPE_MD, 82 .name = "message digest", 83 .bwrite = md_write, 84 .bread = md_read, 85 .bgets = md_gets, 86 .ctrl = md_ctrl, 87 .create = md_new, 88 .destroy = md_free, 89 .callback_ctrl = md_callback_ctrl 90 }; 91 92 const BIO_METHOD * 93 BIO_f_md(void) 94 { 95 return (&methods_md); 96 } 97 98 static int 99 md_new(BIO *bi) 100 { 101 EVP_MD_CTX *ctx; 102 103 ctx = EVP_MD_CTX_create(); 104 if (ctx == NULL) 105 return (0); 106 107 bi->init = 0; 108 bi->ptr = (char *)ctx; 109 bi->flags = 0; 110 return (1); 111 } 112 113 static int 114 md_free(BIO *a) 115 { 116 if (a == NULL) 117 return (0); 118 EVP_MD_CTX_destroy(a->ptr); 119 a->ptr = NULL; 120 a->init = 0; 121 a->flags = 0; 122 return (1); 123 } 124 125 static int 126 md_read(BIO *b, char *out, int outl) 127 { 128 int ret = 0; 129 EVP_MD_CTX *ctx; 130 131 if (out == NULL) 132 return (0); 133 ctx = b->ptr; 134 135 if ((ctx == NULL) || (b->next_bio == NULL)) 136 return (0); 137 138 ret = BIO_read(b->next_bio, out, outl); 139 if (b->init) { 140 if (ret > 0) { 141 if (EVP_DigestUpdate(ctx, (unsigned char *)out, 142 (unsigned int)ret) <= 0) 143 return (-1); 144 } 145 } 146 BIO_clear_retry_flags(b); 147 BIO_copy_next_retry(b); 148 return (ret); 149 } 150 151 static int 152 md_write(BIO *b, const char *in, int inl) 153 { 154 int ret = 0; 155 EVP_MD_CTX *ctx; 156 157 if ((in == NULL) || (inl <= 0)) 158 return (0); 159 ctx = b->ptr; 160 161 if ((ctx != NULL) && (b->next_bio != NULL)) 162 ret = BIO_write(b->next_bio, in, inl); 163 if (b->init) { 164 if (ret > 0) { 165 if (!EVP_DigestUpdate(ctx, (const unsigned char *)in, 166 (unsigned int)ret)) { 167 BIO_clear_retry_flags(b); 168 return 0; 169 } 170 } 171 } 172 if (b->next_bio != NULL) { 173 BIO_clear_retry_flags(b); 174 BIO_copy_next_retry(b); 175 } 176 return (ret); 177 } 178 179 static long 180 md_ctrl(BIO *b, int cmd, long num, void *ptr) 181 { 182 EVP_MD_CTX *ctx, *dctx, **pctx; 183 const EVP_MD **ppmd; 184 EVP_MD *md; 185 long ret = 1; 186 BIO *dbio; 187 188 ctx = b->ptr; 189 190 switch (cmd) { 191 case BIO_CTRL_RESET: 192 if (b->init) 193 ret = EVP_DigestInit_ex(ctx, ctx->digest, NULL); 194 else 195 ret = 0; 196 if (ret > 0) 197 ret = BIO_ctrl(b->next_bio, cmd, num, ptr); 198 break; 199 case BIO_C_GET_MD: 200 if (b->init) { 201 ppmd = ptr; 202 *ppmd = ctx->digest; 203 } else 204 ret = 0; 205 break; 206 case BIO_C_GET_MD_CTX: 207 pctx = ptr; 208 *pctx = ctx; 209 b->init = 1; 210 break; 211 case BIO_C_SET_MD_CTX: 212 if (b->init) 213 b->ptr = ptr; 214 else 215 ret = 0; 216 break; 217 case BIO_C_DO_STATE_MACHINE: 218 BIO_clear_retry_flags(b); 219 ret = BIO_ctrl(b->next_bio, cmd, num, ptr); 220 BIO_copy_next_retry(b); 221 break; 222 223 case BIO_C_SET_MD: 224 md = ptr; 225 ret = EVP_DigestInit_ex(ctx, md, NULL); 226 if (ret > 0) 227 b->init = 1; 228 break; 229 case BIO_CTRL_DUP: 230 dbio = ptr; 231 dctx = dbio->ptr; 232 if (!EVP_MD_CTX_copy_ex(dctx, ctx)) 233 return 0; 234 b->init = 1; 235 break; 236 default: 237 ret = BIO_ctrl(b->next_bio, cmd, num, ptr); 238 break; 239 } 240 return (ret); 241 } 242 243 static long 244 md_callback_ctrl(BIO *b, int cmd, BIO_info_cb *fp) 245 { 246 long ret = 1; 247 248 if (b->next_bio == NULL) 249 return (0); 250 switch (cmd) { 251 default: 252 ret = BIO_callback_ctrl(b->next_bio, cmd, fp); 253 break; 254 } 255 return (ret); 256 } 257 258 static int 259 md_gets(BIO *bp, char *buf, int size) 260 { 261 EVP_MD_CTX *ctx; 262 unsigned int ret; 263 264 ctx = bp->ptr; 265 if (size < ctx->digest->md_size) 266 return (0); 267 if (EVP_DigestFinal_ex(ctx, (unsigned char *)buf, &ret) <= 0) 268 return -1; 269 270 return ((int)ret); 271 } 272 273 /* 274 static int md_puts(bp,str) 275 BIO *bp; 276 char *str; 277 { 278 return(-1); 279 } 280 */ 281