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