lib/libcrypto/asn1/a_d2i_fp.c

   1 /* $OpenBSD: a_d2i_fp.c,v 1.16 2017/01/29 17:49:22 beck 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 <limits.h>
  60 #include <stdio.h>
  61
  62 #include <openssl/asn1.h>
  63 #include <openssl/buffer.h>
  64 #include <openssl/err.h>
  65
  66 static int asn1_d2i_read_bio(BIO *in, BUF_MEM **pb);
  67
  68 #ifndef NO_OLD_ASN1
  69
  70 void *
  71 ASN1_d2i_fp(void *(*xnew)(void), d2i_of_void *d2i, FILE *in, void **x)
  72 {
  73         BIO *b;
  74         void *ret;
  75
  76         if ((b = BIO_new(BIO_s_file())) == NULL) {
  77                 ASN1error(ERR_R_BUF_LIB);
  78                 return (NULL);
  79         }
  80         BIO_set_fp(b, in, BIO_NOCLOSE);
  81         ret = ASN1_d2i_bio(xnew, d2i, b, x);
  82         BIO_free(b);
  83         return (ret);
  84 }
  85
  86 void *
  87 ASN1_d2i_bio(void *(*xnew)(void), d2i_of_void *d2i, BIO *in, void **x)
  88 {
  89         BUF_MEM *b = NULL;
  90         const unsigned char *p;
  91         void *ret = NULL;
  92         int len;
  93
  94         len = asn1_d2i_read_bio(in, &b);
  95         if (len < 0)
  96                 goto err;
  97
  98         p = (unsigned char *)b->data;
  99         ret = d2i(x, &p, len);
 100
 101 err:
 102         if (b != NULL)
 103                 BUF_MEM_free(b);
 104         return (ret);
 105 }
 106
 107 #endif
 108
 109 void *
 110 ASN1_item_d2i_bio(const ASN1_ITEM *it, BIO *in, void *x)
 111 {
 112         BUF_MEM *b = NULL;
 113         const unsigned char *p;
 114         void *ret = NULL;
 115         int len;
 116
 117         len = asn1_d2i_read_bio(in, &b);
 118         if (len < 0)
 119                 goto err;
 120
 121         p = (const unsigned char *)b->data;
 122         ret = ASN1_item_d2i(x, &p, len, it);
 123
 124 err:
 125         if (b != NULL)
 126                 BUF_MEM_free(b);
 127         return (ret);
 128 }
 129
 130 void *
 131 ASN1_item_d2i_fp(const ASN1_ITEM *it, FILE *in, void *x)
 132 {
 133         BIO *b;
 134         char *ret;
 135
 136         if ((b = BIO_new(BIO_s_file())) == NULL) {
 137                 ASN1error(ERR_R_BUF_LIB);
 138                 return (NULL);
 139         }
 140         BIO_set_fp(b, in, BIO_NOCLOSE);
 141         ret = ASN1_item_d2i_bio(it, b, x);
 142         BIO_free(b);
 143         return (ret);
 144 }
 145
 146 #define HEADER_SIZE   8
 147 #define ASN1_CHUNK_INITIAL_SIZE (16 * 1024)
 148 static int
 149 asn1_d2i_read_bio(BIO *in, BUF_MEM **pb)
 150 {
 151         BUF_MEM *b;
 152         unsigned char *p;
 153         int i;
 154         ASN1_const_CTX c;
 155         size_t want = HEADER_SIZE;
 156         int eos = 0;
 157         size_t off = 0;
 158         size_t len = 0;
 159
 160         b = BUF_MEM_new();
 161         if (b == NULL) {
 162                 ASN1error(ERR_R_MALLOC_FAILURE);
 163                 return -1;
 164         }
 165
 166         ERR_clear_error();
 167         for (;;) {
 168                 if (want >= (len - off)) {
 169                         want -= (len - off);
 170
 171                         if (len + want < len ||
 172                             !BUF_MEM_grow_clean(b, len + want)) {
 173                                 ASN1error(ERR_R_MALLOC_FAILURE);
 174                                 goto err;
 175                         }
 176                         i = BIO_read(in, &(b->data[len]), want);
 177                         if ((i < 0) && ((len - off) == 0)) {
 178                                 ASN1error(ASN1_R_NOT_ENOUGH_DATA);
 179                                 goto err;
 180                         }
 181                         if (i > 0) {
 182                                 if (len + i < len) {
 183                                         ASN1error(ASN1_R_TOO_LONG);
 184                                         goto err;
 185                                 }
 186                                 len += i;
 187                         }
 188                 }
 189                 /* else data already loaded */
 190
 191                 p = (unsigned char *) & (b->data[off]);
 192                 c.p = p;
 193                 c.inf = ASN1_get_object(&(c.p), &(c.slen), &(c.tag),
 194                     &(c.xclass), len - off);
 195                 if (c.inf & 0x80) {
 196                         unsigned long e;
 197
 198                         e = ERR_GET_REASON(ERR_peek_error());
 199                         if (e != ASN1_R_TOO_LONG)
 200                                 goto err;
 201                         else
 202                                 ERR_clear_error(); /* clear error */
 203                 }
 204                 i = c.p - p;    /* header length */
 205                 off += i;       /* end of data */
 206
 207                 if (c.inf & 1) {
 208                         /* no data body so go round again */
 209                         eos++;
 210                         if (eos < 0) {
 211                                 ASN1error(ASN1_R_HEADER_TOO_LONG);
 212                                 goto err;
 213                         }
 214                         want = HEADER_SIZE;
 215                 } else if (eos && (c.slen == 0) && (c.tag == V_ASN1_EOC)) {
 216                         /* eos value, so go back and read another header */
 217                         eos--;
 218                         if (eos <= 0)
 219                                 break;
 220                         else
 221                                 want = HEADER_SIZE;
 222                 } else {
 223                         /* suck in c.slen bytes of data */
 224                         want = c.slen;
 225                         if (want > (len - off)) {
 226                                 size_t chunk_max = ASN1_CHUNK_INITIAL_SIZE;
 227
 228                                 want -= (len - off);
 229                                 if (want > INT_MAX /* BIO_read takes an int length */ ||
 230                                     len+want < len) {
 231                                         ASN1error(ASN1_R_TOO_LONG);
 232                                         goto err;
 233                                 }
 234                                 while (want > 0) {
 235                                         /*
 236                                          * Read content in chunks of increasing size
 237                                          * so we can return an error for EOF without
 238                                          * having to allocate the entire content length
 239                                          * in one go.
 240                                          */
 241                                         size_t chunk = want > chunk_max ? chunk_max : want;
 242
 243                                         if (!BUF_MEM_grow_clean(b, len + chunk)) {
 244                                                 ASN1error(ERR_R_MALLOC_FAILURE);
 245                                                 goto err;
 246                                         }
 247                                         want -= chunk;
 248                                         while (chunk > 0) {
 249                                                 i = BIO_read(in, &(b->data[len]), chunk);
 250                                                 if (i <= 0) {
 251                                                         ASN1error(ASN1_R_NOT_ENOUGH_DATA);
 252                                                         goto err;
 253                                                 }
 254                                                 /*
 255                                                  * This can't overflow because |len+want|
 256                                                  * didn't overflow.
 257                                                  */
 258                                                 len += i;
 259                                                 chunk -= i;
 260                                         }
 261                                         if (chunk_max < INT_MAX/2)
 262                                                 chunk_max *= 2;
 263                                 }
 264                         }
 265                         if (off + c.slen < off) {
 266                                 ASN1error(ASN1_R_TOO_LONG);
 267                                 goto err;
 268                         }
 269                         off += c.slen;
 270                         if (eos <= 0) {
 271                                 break;
 272                         } else
 273                                 want = HEADER_SIZE;
 274                 }
 275         }
 276
 277         if (off > INT_MAX) {
 278                 ASN1error(ASN1_R_TOO_LONG);
 279                 goto err;
 280         }
 281
 282         *pb = b;
 283         return off;
 284
 285 err:
 286         if (b != NULL)
 287                 BUF_MEM_free(b);
 288         return -1;
 289 }