crypto/asn1/a_verify.c

   1 /* crypto/asn1/a_verify.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 <stdio.h>
  60 #include <time.h>
  61
  62 #include "cryptlib.h"
  63
  64 #ifndef NO_SYS_TYPES_H
  65 # include <sys/types.h>
  66 #endif
  67
  68 #include <openssl/bn.h>
  69 #include <openssl/x509.h>
  70 #include <openssl/objects.h>
  71 #include <openssl/buffer.h>
  72 #include <openssl/evp.h>
  73 #include "asn1_locl.h"
  74
  75 #ifndef NO_ASN1_OLD
  76
  77 int ASN1_verify(i2d_of_void *i2d, X509_ALGOR *a, ASN1_BIT_STRING *signature,
  78                 char *data, EVP_PKEY *pkey)
  79 {
  80     EVP_MD_CTX ctx;
  81     const EVP_MD *type;
  82     unsigned char *p, *buf_in = NULL;
  83     int ret = -1, i, inl;
  84
  85     EVP_MD_CTX_init(&ctx);
  86     i = OBJ_obj2nid(a->algorithm);
  87     type = EVP_get_digestbyname(OBJ_nid2sn(i));
  88     if (type == NULL) {
  89         ASN1err(ASN1_F_ASN1_VERIFY, ASN1_R_UNKNOWN_MESSAGE_DIGEST_ALGORITHM);
  90         goto err;
  91     }
  92
  93     if (signature->type == V_ASN1_BIT_STRING && signature->flags & 0x7) {
  94         ASN1err(ASN1_F_ASN1_VERIFY, ASN1_R_INVALID_BIT_STRING_BITS_LEFT);
  95         goto err;
  96     }
  97
  98     inl = i2d(data, NULL);
  99     buf_in = OPENSSL_malloc((unsigned int)inl);
 100     if (buf_in == NULL) {
 101         ASN1err(ASN1_F_ASN1_VERIFY, ERR_R_MALLOC_FAILURE);
 102         goto err;
 103     }
 104     p = buf_in;
 105
 106     i2d(data, &p);
 107     ret = EVP_VerifyInit_ex(&ctx, type, NULL)
 108         && EVP_VerifyUpdate(&ctx, (unsigned char *)buf_in, inl);
 109
 110     OPENSSL_cleanse(buf_in, (unsigned int)inl);
 111     OPENSSL_free(buf_in);
 112
 113     if (!ret) {
 114         ASN1err(ASN1_F_ASN1_VERIFY, ERR_R_EVP_LIB);
 115         goto err;
 116     }
 117     ret = -1;
 118
 119     if (EVP_VerifyFinal(&ctx, (unsigned char *)signature->data,
 120                         (unsigned int)signature->length, pkey) <= 0) {
 121         ASN1err(ASN1_F_ASN1_VERIFY, ERR_R_EVP_LIB);
 122         ret = 0;
 123         goto err;
 124     }
 125     /*
 126      * we don't need to zero the 'ctx' because we just checked public
 127      * information
 128      */
 129     /* memset(&ctx,0,sizeof(ctx)); */
 130     ret = 1;
 131  err:
 132     EVP_MD_CTX_cleanup(&ctx);
 133     return (ret);
 134 }
 135
 136 #endif
 137
 138 int ASN1_item_verify(const ASN1_ITEM *it, X509_ALGOR *a,
 139                      ASN1_BIT_STRING *signature, void *asn, EVP_PKEY *pkey)
 140 {
 141     EVP_MD_CTX ctx;
 142     unsigned char *buf_in = NULL;
 143     int ret = -1, inl;
 144
 145     int mdnid, pknid;
 146
 147     if (!pkey) {
 148         ASN1err(ASN1_F_ASN1_ITEM_VERIFY, ERR_R_PASSED_NULL_PARAMETER);
 149         return -1;
 150     }
 151
 152     if (signature->type == V_ASN1_BIT_STRING && signature->flags & 0x7) {
 153         ASN1err(ASN1_F_ASN1_ITEM_VERIFY, ASN1_R_INVALID_BIT_STRING_BITS_LEFT);
 154         return -1;
 155     }
 156
 157     EVP_MD_CTX_init(&ctx);
 158
 159     /* Convert signature OID into digest and public key OIDs */
 160     if (!OBJ_find_sigid_algs(OBJ_obj2nid(a->algorithm), &mdnid, &pknid)) {
 161         ASN1err(ASN1_F_ASN1_ITEM_VERIFY, ASN1_R_UNKNOWN_SIGNATURE_ALGORITHM);
 162         goto err;
 163     }
 164     if (mdnid == NID_undef) {
 165         if (!pkey->ameth || !pkey->ameth->item_verify) {
 166             ASN1err(ASN1_F_ASN1_ITEM_VERIFY,
 167                     ASN1_R_UNKNOWN_SIGNATURE_ALGORITHM);
 168             goto err;
 169         }
 170         ret = pkey->ameth->item_verify(&ctx, it, asn, a, signature, pkey);
 171         /*
 172          * Return value of 2 means carry on, anything else means we exit
 173          * straight away: either a fatal error of the underlying verification
 174          * routine handles all verification.
 175          */
 176         if (ret != 2)
 177             goto err;
 178         ret = -1;
 179     } else {
 180         const EVP_MD *type;
 181         type = EVP_get_digestbynid(mdnid);
 182         if (type == NULL) {
 183             ASN1err(ASN1_F_ASN1_ITEM_VERIFY,
 184                     ASN1_R_UNKNOWN_MESSAGE_DIGEST_ALGORITHM);
 185             goto err;
 186         }
 187
 188         /* Check public key OID matches public key type */
 189         if (EVP_PKEY_type(pknid) != pkey->ameth->pkey_id) {
 190             ASN1err(ASN1_F_ASN1_ITEM_VERIFY, ASN1_R_WRONG_PUBLIC_KEY_TYPE);
 191             goto err;
 192         }
 193
 194         if (!EVP_DigestVerifyInit(&ctx, NULL, type, NULL, pkey)) {
 195             ASN1err(ASN1_F_ASN1_ITEM_VERIFY, ERR_R_EVP_LIB);
 196             ret = 0;
 197             goto err;
 198         }
 199
 200     }
 201
 202     inl = ASN1_item_i2d(asn, &buf_in, it);
 203
 204     if (buf_in == NULL) {
 205         ASN1err(ASN1_F_ASN1_ITEM_VERIFY, ERR_R_MALLOC_FAILURE);
 206         goto err;
 207     }
 208
 209     ret = EVP_DigestVerifyUpdate(&ctx, buf_in, inl);
 210
 211     OPENSSL_cleanse(buf_in, (unsigned int)inl);
 212     OPENSSL_free(buf_in);
 213
 214     if (!ret) {
 215         ASN1err(ASN1_F_ASN1_ITEM_VERIFY, ERR_R_EVP_LIB);
 216         goto err;
 217     }
 218     ret = -1;
 219
 220     if (EVP_DigestVerifyFinal(&ctx, signature->data,
 221                               (size_t)signature->length) <= 0) {
 222         ASN1err(ASN1_F_ASN1_ITEM_VERIFY, ERR_R_EVP_LIB);
 223         ret = 0;
 224         goto err;
 225     }
 226     /*
 227      * we don't need to zero the 'ctx' because we just checked public
 228      * information
 229      */
 230     /* memset(&ctx,0,sizeof(ctx)); */
 231     ret = 1;
 232  err:
 233     EVP_MD_CTX_cleanup(&ctx);
 234     return (ret);
 235 }