crypto/asn1/a_verify.c

   1 /*
   2  * Copyright 1995-2023 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 #include "crypto/rsa.h"
  24
  25 #ifndef OPENSSL_NO_DEPRECATED_3_0
  26
  27 int ASN1_verify(i2d_of_void *i2d, X509_ALGOR *a, ASN1_BIT_STRING *signature,
  28                 char *data, EVP_PKEY *pkey)
  29 {
  30     EVP_MD_CTX *ctx = EVP_MD_CTX_new();
  31     const EVP_MD *type;
  32     unsigned char *p, *buf_in = NULL;
  33     int ret = -1, i, inl;
  34
  35     if (ctx == NULL) {
  36         ERR_raise(ERR_LIB_ASN1, ERR_R_EVP_LIB);
  37         goto err;
  38     }
  39     i = OBJ_obj2nid(a->algorithm);
  40     type = EVP_get_digestbyname(OBJ_nid2sn(i));
  41     if (type == NULL) {
  42         ERR_raise(ERR_LIB_ASN1, ASN1_R_UNKNOWN_MESSAGE_DIGEST_ALGORITHM);
  43         goto err;
  44     }
  45
  46     if (signature->type == V_ASN1_BIT_STRING && signature->flags & 0x7) {
  47         ERR_raise(ERR_LIB_ASN1, ASN1_R_INVALID_BIT_STRING_BITS_LEFT);
  48         goto err;
  49     }
  50
  51     inl = i2d(data, NULL);
  52     if (inl <= 0) {
  53         ERR_raise(ERR_LIB_ASN1, ERR_R_INTERNAL_ERROR);
  54         goto err;
  55     }
  56     buf_in = OPENSSL_malloc((unsigned int)inl);
  57     if (buf_in == NULL)
  58         goto err;
  59     p = buf_in;
  60
  61     i2d(data, &p);
  62     ret = EVP_VerifyInit_ex(ctx, type, NULL)
  63         && EVP_VerifyUpdate(ctx, (unsigned char *)buf_in, inl);
  64
  65     OPENSSL_clear_free(buf_in, (unsigned int)inl);
  66
  67     if (!ret) {
  68         ERR_raise(ERR_LIB_ASN1, ERR_R_EVP_LIB);
  69         goto err;
  70     }
  71     ret = -1;
  72
  73     if (EVP_VerifyFinal(ctx, (unsigned char *)signature->data,
  74                         (unsigned int)signature->length, pkey) <= 0) {
  75         ERR_raise(ERR_LIB_ASN1, ERR_R_EVP_LIB);
  76         ret = 0;
  77         goto err;
  78     }
  79     ret = 1;
  80  err:
  81     EVP_MD_CTX_free(ctx);
  82     return ret;
  83 }
  84
  85 #endif
  86
  87 int ASN1_item_verify(const ASN1_ITEM *it, const X509_ALGOR *alg,
  88                      const ASN1_BIT_STRING *signature, const void *data,
  89                      EVP_PKEY *pkey)
  90 {
  91     return ASN1_item_verify_ex(it, alg, signature, data, NULL, pkey, NULL, NULL);
  92 }
  93
  94 int ASN1_item_verify_ex(const ASN1_ITEM *it, const X509_ALGOR *alg,
  95                         const ASN1_BIT_STRING *signature, const void *data,
  96                         const ASN1_OCTET_STRING *id, EVP_PKEY *pkey,
  97                         OSSL_LIB_CTX *libctx, const char *propq)
  98 {
  99     EVP_MD_CTX *ctx;
 100     int rv = -1;
 101
 102     if ((ctx = evp_md_ctx_new_ex(pkey, id, libctx, propq)) != NULL) {
 103         rv = ASN1_item_verify_ctx(it, alg, signature, data, ctx);
 104         EVP_PKEY_CTX_free(EVP_MD_CTX_get_pkey_ctx(ctx));
 105         EVP_MD_CTX_free(ctx);
 106     }
 107     return rv;
 108 }
 109
 110 int ASN1_item_verify_ctx(const ASN1_ITEM *it, const X509_ALGOR *alg,
 111                          const ASN1_BIT_STRING *signature, const void *data,
 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_get_pkey_ctx(ctx));
 121
 122     if (pkey == NULL) {
 123         ERR_raise(ERR_LIB_ASN1, ERR_R_PASSED_NULL_PARAMETER);
 124         return -1;
 125     }
 126
 127     if (signature->type == V_ASN1_BIT_STRING && signature->flags & 0x7) {
 128         ERR_raise(ERR_LIB_ASN1, 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(alg->algorithm), &mdnid, &pknid)) {
 134         ERR_raise(ERR_LIB_ASN1, ASN1_R_UNKNOWN_SIGNATURE_ALGORITHM);
 135         goto err;
 136     }
 137
 138     if (mdnid == NID_undef && evp_pkey_is_legacy(pkey)) {
 139         if (pkey->ameth == NULL || pkey->ameth->item_verify == NULL) {
 140             ERR_raise(ERR_LIB_ASN1, ASN1_R_UNKNOWN_SIGNATURE_ALGORITHM);
 141             goto err;
 142         }
 143         ret = pkey->ameth->item_verify(ctx, it, data, alg, 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             ERR_raise(ERR_LIB_ASN1, ERR_R_EVP_LIB);
 152         if (ret <= 1)
 153             goto err;
 154     } else {
 155         const EVP_MD *type = NULL;
 156
 157         /*
 158          * We don't yet have the ability for providers to be able to handle
 159          * X509_ALGOR style parameters. Fortunately the only one that needs this
 160          * so far is RSA-PSS, so we just special case this for now. In some
 161          * future version of OpenSSL we should push this to the provider.
 162          */
 163         if (mdnid == NID_undef && pknid == EVP_PKEY_RSA_PSS) {
 164             if (!EVP_PKEY_is_a(pkey, "RSA") && !EVP_PKEY_is_a(pkey, "RSA-PSS")) {
 165                 ERR_raise(ERR_LIB_ASN1, ASN1_R_WRONG_PUBLIC_KEY_TYPE);
 166                 goto err;
 167             }
 168             /* This function also calls EVP_DigestVerifyInit */
 169             if (ossl_rsa_pss_to_ctx(ctx, NULL, alg, pkey) <= 0) {
 170                 ERR_raise(ERR_LIB_ASN1, ERR_R_INTERNAL_ERROR);
 171                 goto err;
 172             }
 173         } else {
 174             /* Check public key OID matches public key type */
 175             if (!EVP_PKEY_is_a(pkey, OBJ_nid2sn(pknid))) {
 176                 ERR_raise(ERR_LIB_ASN1, ASN1_R_WRONG_PUBLIC_KEY_TYPE);
 177                 goto err;
 178             }
 179
 180             if (mdnid != NID_undef) {
 181                 type = EVP_get_digestbynid(mdnid);
 182                 if (type == NULL) {
 183                     ERR_raise_data(ERR_LIB_ASN1,
 184                                    ASN1_R_UNKNOWN_MESSAGE_DIGEST_ALGORITHM,
 185                                    "nid=0x%x", mdnid);
 186                     goto err;
 187                 }
 188             }
 189
 190             /*
 191              * Note that some algorithms (notably Ed25519 and Ed448) may allow
 192              * a NULL digest value.
 193              */
 194             if (!EVP_DigestVerifyInit(ctx, NULL, type, NULL, pkey)) {
 195                 ERR_raise(ERR_LIB_ASN1, ERR_R_EVP_LIB);
 196                 ret = 0;
 197                 goto err;
 198             }
 199         }
 200     }
 201
 202     inl = ASN1_item_i2d(data, &buf_in, it);
 203     if (inl <= 0) {
 204         ERR_raise(ERR_LIB_ASN1, ERR_R_INTERNAL_ERROR);
 205         goto err;
 206     }
 207     if (buf_in == NULL) {
 208         ERR_raise(ERR_LIB_ASN1, ERR_R_ASN1_LIB);
 209         goto err;
 210     }
 211     inll = inl;
 212
 213     ret = EVP_DigestVerify(ctx, signature->data, (size_t)signature->length,
 214                            buf_in, inl);
 215     if (ret <= 0) {
 216         ERR_raise(ERR_LIB_ASN1, ERR_R_EVP_LIB);
 217         goto err;
 218     }
 219     ret = 1;
 220  err:
 221     OPENSSL_clear_free(buf_in, inll);
 222     return ret;
 223 }