crypto/evp/bio_md.c

   1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
   2  * All rights reserved.
   3  *
   4  * This package is an SSL implementation written
   5  * by Eric Young (eay@cryptsoft.com).
   6  * The implementation was written so as to conform with Netscapes SSL.
   7  *
   8  * This library is free for commercial and non-commercial use as long as
   9  * the following conditions are aheared to.  The following conditions
  10  * apply to all code found in this distribution, be it the RC4, RSA,
  11  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  12  * included with this distribution is covered by the same copyright terms
  13  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  14  *
  15  * Copyright remains Eric Young's, and as such any Copyright notices in
  16  * the code are not to be removed.
  17  * If this package is used in a product, Eric Young should be given attribution
  18  * as the author of the parts of the library used.
  19  * This can be in the form of a textual message at program startup or
  20  * in documentation (online or textual) provided with the package.
  21  *
  22  * Redistribution and use in source and binary forms, with or without
  23  * modification, are permitted provided that the following conditions
  24  * are met:
  25  * 1. Redistributions of source code must retain the copyright
  26  *    notice, this list of conditions and the following disclaimer.
  27  * 2. Redistributions in binary form must reproduce the above copyright
  28  *    notice, this list of conditions and the following disclaimer in the
  29  *    documentation and/or other materials provided with the distribution.
  30  * 3. All advertising materials mentioning features or use of this software
  31  *    must display the following acknowledgement:
  32  *    "This product includes cryptographic software written by
  33  *     Eric Young (eay@cryptsoft.com)"
  34  *    The word 'cryptographic' can be left out if the rouines from the library
  35  *    being used are not cryptographic related :-).
  36  * 4. If you include any Windows specific code (or a derivative thereof) from
  37  *    the apps directory (application code) you must include an acknowledgement:
  38  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  39  *
  40  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  41  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  43  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  44  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  45  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  46  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  48  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  49  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  50  * SUCH DAMAGE.
  51  *
  52  * The licence and distribution terms for any publically available version or
  53  * derivative of this code cannot be changed.  i.e. this code cannot simply be
  54  * copied and put under another distribution licence
  55  * [including the GNU Public Licence.]
  56  */
  57
  58 #include <stdio.h>
  59 #include <errno.h>
  60 #include "internal/cryptlib.h"
  61 #include <openssl/buffer.h>
  62 #include <openssl/evp.h>
  63 #include "internal/evp_int.h"
  64 #include "evp_locl.h"
  65
  66 /*
  67  * BIO_put and BIO_get both add to the digest, BIO_gets returns the digest
  68  */
  69
  70 static int md_write(BIO *h, char const *buf, int num);
  71 static int md_read(BIO *h, char *buf, int size);
  72 /*
  73  * static int md_puts(BIO *h, const char *str);
  74  */
  75 static int md_gets(BIO *h, char *str, int size);
  76 static long md_ctrl(BIO *h, int cmd, long arg1, void *arg2);
  77 static int md_new(BIO *h);
  78 static int md_free(BIO *data);
  79 static long md_callback_ctrl(BIO *h, int cmd, bio_info_cb *fp);
  80
  81 static const BIO_METHOD methods_md = {
  82     BIO_TYPE_MD, "message digest",
  83     md_write,
  84     md_read,
  85     NULL,                       /* md_puts, */
  86     md_gets,
  87     md_ctrl,
  88     md_new,
  89     md_free,
  90     md_callback_ctrl,
  91 };
  92
  93 const BIO_METHOD *BIO_f_md(void)
  94 {
  95     return (&methods_md);
  96 }
  97
  98 static int md_new(BIO *bi)
  99 {
 100     EVP_MD_CTX *ctx;
 101
 102     ctx = EVP_MD_CTX_new();
 103     if (ctx == NULL)
 104         return (0);
 105
 106     bi->init = 0;
 107     bi->ptr = (char *)ctx;
 108     bi->flags = 0;
 109     return (1);
 110 }
 111
 112 static int md_free(BIO *a)
 113 {
 114     if (a == NULL)
 115         return (0);
 116     EVP_MD_CTX_free(a->ptr);
 117     a->ptr = NULL;
 118     a->init = 0;
 119     a->flags = 0;
 120     return (1);
 121 }
 122
 123 static int md_read(BIO *b, char *out, int outl)
 124 {
 125     int ret = 0;
 126     EVP_MD_CTX *ctx;
 127
 128     if (out == NULL)
 129         return (0);
 130     ctx = b->ptr;
 131
 132     if ((ctx == NULL) || (b->next_bio == NULL))
 133         return (0);
 134
 135     ret = BIO_read(b->next_bio, out, outl);
 136     if (b->init) {
 137         if (ret > 0) {
 138             if (EVP_DigestUpdate(ctx, (unsigned char *)out,
 139                                  (unsigned int)ret) <= 0)
 140                 return (-1);
 141         }
 142     }
 143     BIO_clear_retry_flags(b);
 144     BIO_copy_next_retry(b);
 145     return (ret);
 146 }
 147
 148 static int md_write(BIO *b, const char *in, int inl)
 149 {
 150     int ret = 0;
 151     EVP_MD_CTX *ctx;
 152
 153     if ((in == NULL) || (inl <= 0))
 154         return (0);
 155     ctx = b->ptr;
 156
 157     if ((ctx != NULL) && (b->next_bio != NULL))
 158         ret = BIO_write(b->next_bio, in, inl);
 159     if (b->init) {
 160         if (ret > 0) {
 161             if (!EVP_DigestUpdate(ctx, (const unsigned char *)in,
 162                                   (unsigned int)ret)) {
 163                 BIO_clear_retry_flags(b);
 164                 return 0;
 165             }
 166         }
 167     }
 168     if (b->next_bio != NULL) {
 169         BIO_clear_retry_flags(b);
 170         BIO_copy_next_retry(b);
 171     }
 172     return (ret);
 173 }
 174
 175 static long md_ctrl(BIO *b, int cmd, long num, void *ptr)
 176 {
 177     EVP_MD_CTX *ctx, *dctx, **pctx;
 178     const EVP_MD **ppmd;
 179     EVP_MD *md;
 180     long ret = 1;
 181     BIO *dbio;
 182
 183     ctx = b->ptr;
 184
 185     switch (cmd) {
 186     case BIO_CTRL_RESET:
 187         if (b->init)
 188             ret = EVP_DigestInit_ex(ctx, ctx->digest, NULL);
 189         else
 190             ret = 0;
 191         if (ret > 0)
 192             ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
 193         break;
 194     case BIO_C_GET_MD:
 195         if (b->init) {
 196             ppmd = ptr;
 197             *ppmd = ctx->digest;
 198         } else
 199             ret = 0;
 200         break;
 201     case BIO_C_GET_MD_CTX:
 202         pctx = ptr;
 203         *pctx = ctx;
 204         b->init = 1;
 205         break;
 206     case BIO_C_SET_MD_CTX:
 207         if (b->init)
 208             b->ptr = ptr;
 209         else
 210             ret = 0;
 211         break;
 212     case BIO_C_DO_STATE_MACHINE:
 213         BIO_clear_retry_flags(b);
 214         ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
 215         BIO_copy_next_retry(b);
 216         break;
 217
 218     case BIO_C_SET_MD:
 219         md = ptr;
 220         ret = EVP_DigestInit_ex(ctx, md, NULL);
 221         if (ret > 0)
 222             b->init = 1;
 223         break;
 224     case BIO_CTRL_DUP:
 225         dbio = ptr;
 226         dctx = dbio->ptr;
 227         if (!EVP_MD_CTX_copy_ex(dctx, ctx))
 228             return 0;
 229         b->init = 1;
 230         break;
 231     default:
 232         ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
 233         break;
 234     }
 235     return (ret);
 236 }
 237
 238 static long md_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp)
 239 {
 240     long ret = 1;
 241
 242     if (b->next_bio == NULL)
 243         return (0);
 244     switch (cmd) {
 245     default:
 246         ret = BIO_callback_ctrl(b->next_bio, cmd, fp);
 247         break;
 248     }
 249     return (ret);
 250 }
 251
 252 static int md_gets(BIO *bp, char *buf, int size)
 253 {
 254     EVP_MD_CTX *ctx;
 255     unsigned int ret;
 256
 257     ctx = bp->ptr;
 258     if (size < ctx->digest->md_size)
 259         return (0);
 260     if (EVP_DigestFinal_ex(ctx, (unsigned char *)buf, &ret) <= 0)
 261         return -1;
 262
 263     return ((int)ret);
 264 }
 265
 266 /*-
 267 static int md_puts(bp,str)
 268 BIO *bp;
 269 char *str;
 270         {
 271         return(-1);
 272         }
 273 */