crypto/asn1/a_verify.c

   1 /*
   2  * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #include <stdio.h>
  11 #include <time.h>
  12 #include <sys/types.h>
  13
  14 #include "internal/cryptlib.h"
  15
  16 #include <openssl/bn.h>
  17 #include <openssl/x509.h>
  18 #include <openssl/objects.h>
  19 #include <openssl/buffer.h>
  20 #include <openssl/evp.h>
  21 #include "crypto/asn1.h"
  22 #include "crypto/evp.h"
  23
  24 #ifndef NO_ASN1_OLD
  25
  26 int ASN1_verify(i2d_of_void *i2d, X509_ALGOR *a, ASN1_BIT_STRING *signature,
  27                 char *data, EVP_PKEY *pkey)
  28 {
  29     EVP_MD_CTX *ctx = EVP_MD_CTX_new();
  30     const EVP_MD *type;
  31     unsigned char *p, *buf_in = NULL;
  32     int ret = -1, i, inl;
  33
  34     if (ctx == NULL) {
  35         ASN1err(ASN1_F_ASN1_VERIFY, ERR_R_MALLOC_FAILURE);
  36         goto err;
  37     }
  38     i = OBJ_obj2nid(a->algorithm);
  39     type = EVP_get_digestbyname(OBJ_nid2sn(i));
  40     if (type == NULL) {
  41         ASN1err(ASN1_F_ASN1_VERIFY, ASN1_R_UNKNOWN_MESSAGE_DIGEST_ALGORITHM);
  42         goto err;
  43     }
  44
  45     if (signature->type == V_ASN1_BIT_STRING && signature->flags & 0x7) {
  46         ASN1err(ASN1_F_ASN1_VERIFY, ASN1_R_INVALID_BIT_STRING_BITS_LEFT);
  47         goto err;
  48     }
  49
  50     inl = i2d(data, NULL);
  51     if (inl <= 0) {
  52         ASN1err(ASN1_F_ASN1_VERIFY, ERR_R_INTERNAL_ERROR);
  53         goto err;
  54     }
  55     buf_in = OPENSSL_malloc((unsigned int)inl);
  56     if (buf_in == NULL) {
  57         ASN1err(ASN1_F_ASN1_VERIFY, ERR_R_MALLOC_FAILURE);
  58         goto err;
  59     }
  60     p = buf_in;
  61
  62     i2d(data, &p);
  63     ret = EVP_VerifyInit_ex(ctx, type, NULL)
  64         && EVP_VerifyUpdate(ctx, (unsigned char *)buf_in, inl);
  65
  66     OPENSSL_clear_free(buf_in, (unsigned int)inl);
  67
  68     if (!ret) {
  69         ASN1err(ASN1_F_ASN1_VERIFY, ERR_R_EVP_LIB);
  70         goto err;
  71     }
  72     ret = -1;
  73
  74     if (EVP_VerifyFinal(ctx, (unsigned char *)signature->data,
  75                         (unsigned int)signature->length, pkey) <= 0) {
  76         ASN1err(ASN1_F_ASN1_VERIFY, ERR_R_EVP_LIB);
  77         ret = 0;
  78         goto err;
  79     }
  80     ret = 1;
  81  err:
  82     EVP_MD_CTX_free(ctx);
  83     return ret;
  84 }
  85
  86 #endif
  87
  88 int ASN1_item_verify(const ASN1_ITEM *it, X509_ALGOR *a,
  89                      ASN1_BIT_STRING *signature, void *asn, EVP_PKEY *pkey)
  90 {
  91     int rv = -1;
  92     EVP_MD_CTX *ctx = EVP_MD_CTX_new();
  93     EVP_PKEY_CTX *pctx = EVP_PKEY_CTX_new(pkey, NULL);
  94
  95     if (ctx == NULL || pctx == NULL) {
  96         ASN1err(0, ERR_R_MALLOC_FAILURE);
  97         goto err;
  98     }
  99
 100     EVP_MD_CTX_set_pkey_ctx(ctx, pctx);
 101
 102     rv = ASN1_item_verify_ctx(it, a, signature, asn, ctx);
 103
 104  err:
 105     EVP_PKEY_CTX_free(pctx);
 106     EVP_MD_CTX_free(ctx);
 107     return rv;
 108 }
 109
 110 int ASN1_item_verify_ctx(const ASN1_ITEM *it, X509_ALGOR *a,
 111                          ASN1_BIT_STRING *signature, void *asn,
 112                          EVP_MD_CTX *ctx)
 113 {
 114     EVP_PKEY *pkey;
 115     unsigned char *buf_in = NULL;
 116     int ret = -1, inl = 0;
 117     int mdnid, pknid;
 118     size_t inll = 0;
 119
 120     pkey = EVP_PKEY_CTX_get0_pkey(EVP_MD_CTX_pkey_ctx(ctx));
 121
 122     if (pkey == NULL) {
 123         ASN1err(0, ERR_R_PASSED_NULL_PARAMETER);
 124         return -1;
 125     }
 126
 127     if (signature->type == V_ASN1_BIT_STRING && signature->flags & 0x7) {
 128         ASN1err(0, ASN1_R_INVALID_BIT_STRING_BITS_LEFT);
 129         return -1;
 130     }
 131
 132     /* Convert signature OID into digest and public key OIDs */
 133     if (!OBJ_find_sigid_algs(OBJ_obj2nid(a->algorithm), &mdnid, &pknid)) {
 134         ASN1err(0, ASN1_R_UNKNOWN_SIGNATURE_ALGORITHM);
 135         goto err;
 136     }
 137
 138     if (mdnid == NID_undef) {
 139         if (pkey->ameth == NULL || pkey->ameth->item_verify == NULL) {
 140             ASN1err(0, ASN1_R_UNKNOWN_SIGNATURE_ALGORITHM);
 141             goto err;
 142         }
 143         ret = pkey->ameth->item_verify(ctx, it, asn, a, signature, pkey);
 144         /*
 145          * Return values meaning:
 146          * <=0: error.
 147          *   1: method does everything.
 148          *   2: carry on as normal, method has called EVP_DigestVerifyInit()
 149          */
 150         if (ret <= 0)
 151             ASN1err(0, ERR_R_EVP_LIB);
 152         if (ret <= 1)
 153             goto err;
 154     } else {
 155         const EVP_MD *type = EVP_get_digestbynid(mdnid);
 156
 157         if (type == NULL) {
 158             ASN1err(0, ASN1_R_UNKNOWN_MESSAGE_DIGEST_ALGORITHM);
 159             goto err;
 160         }
 161
 162         /* Check public key OID matches public key type */
 163         if (EVP_PKEY_type(pknid) != pkey->ameth->pkey_id) {
 164             ASN1err(0, ASN1_R_WRONG_PUBLIC_KEY_TYPE);
 165             goto err;
 166         }
 167
 168         if (!EVP_DigestVerifyInit(ctx, NULL, type, NULL, pkey)) {
 169             ASN1err(0, ERR_R_EVP_LIB);
 170             ret = 0;
 171             goto err;
 172         }
 173     }
 174
 175     inl = ASN1_item_i2d(asn, &buf_in, it);
 176     if (inl <= 0) {
 177         ASN1err(0, ERR_R_INTERNAL_ERROR);
 178         goto err;
 179     }
 180     if (buf_in == NULL) {
 181         ASN1err(0, ERR_R_MALLOC_FAILURE);
 182         goto err;
 183     }
 184     inll = inl;
 185
 186     ret = EVP_DigestVerify(ctx, signature->data, (size_t)signature->length,
 187                            buf_in, inl);
 188     if (ret <= 0) {
 189         ASN1err(0, ERR_R_EVP_LIB);
 190         goto err;
 191     }
 192     ret = 1;
 193  err:
 194     OPENSSL_clear_free(buf_in, inll);
 195     return ret;
 196 }