crypto/asn1/x_algor.c

   1 /*
   2  * Copyright 1998-2021 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 <stddef.h>
  11 #include <openssl/x509.h>
  12 #include <openssl/asn1.h>
  13 #include <openssl/asn1t.h>
  14 #include <openssl/err.h>
  15 #include "crypto/asn1.h"
  16 #include "crypto/evp.h"
  17
  18 ASN1_SEQUENCE(X509_ALGOR) = {
  19         ASN1_SIMPLE(X509_ALGOR, algorithm, ASN1_OBJECT),
  20         ASN1_OPT(X509_ALGOR, parameter, ASN1_ANY)
  21 } ASN1_SEQUENCE_END(X509_ALGOR)
  22
  23 ASN1_ITEM_TEMPLATE(X509_ALGORS) =
  24         ASN1_EX_TEMPLATE_TYPE(ASN1_TFLG_SEQUENCE_OF, 0, algorithms, X509_ALGOR)
  25 ASN1_ITEM_TEMPLATE_END(X509_ALGORS)
  26
  27 IMPLEMENT_ASN1_FUNCTIONS(X509_ALGOR)
  28 IMPLEMENT_ASN1_ENCODE_FUNCTIONS_fname(X509_ALGORS, X509_ALGORS, X509_ALGORS)
  29 IMPLEMENT_ASN1_DUP_FUNCTION(X509_ALGOR)
  30
  31 int X509_ALGOR_set0(X509_ALGOR *alg, ASN1_OBJECT *aobj, int ptype, void *pval)
  32 {
  33     if (alg == NULL)
  34         return 0;
  35
  36     if (ptype != V_ASN1_UNDEF) {
  37         if (alg->parameter == NULL)
  38             alg->parameter = ASN1_TYPE_new();
  39         if (alg->parameter == NULL)
  40             return 0;
  41     }
  42
  43     ASN1_OBJECT_free(alg->algorithm);
  44     alg->algorithm = aobj;
  45
  46     if (ptype == 0)
  47         return 1;
  48     if (ptype == V_ASN1_UNDEF) {
  49         ASN1_TYPE_free(alg->parameter);
  50         alg->parameter = NULL;
  51     } else
  52         ASN1_TYPE_set(alg->parameter, ptype, pval);
  53     return 1;
  54 }
  55
  56 void X509_ALGOR_get0(const ASN1_OBJECT **paobj, int *pptype,
  57                      const void **ppval, const X509_ALGOR *algor)
  58 {
  59     if (paobj)
  60         *paobj = algor->algorithm;
  61     if (pptype) {
  62         if (algor->parameter == NULL) {
  63             *pptype = V_ASN1_UNDEF;
  64             return;
  65         } else
  66             *pptype = algor->parameter->type;
  67         if (ppval)
  68             *ppval = algor->parameter->value.ptr;
  69     }
  70 }
  71
  72 /* Set up an X509_ALGOR DigestAlgorithmIdentifier from an EVP_MD */
  73
  74 void X509_ALGOR_set_md(X509_ALGOR *alg, const EVP_MD *md)
  75 {
  76     int param_type;
  77
  78     if (md->flags & EVP_MD_FLAG_DIGALGID_ABSENT)
  79         param_type = V_ASN1_UNDEF;
  80     else
  81         param_type = V_ASN1_NULL;
  82
  83     X509_ALGOR_set0(alg, OBJ_nid2obj(EVP_MD_type(md)), param_type, NULL);
  84
  85 }
  86
  87 int X509_ALGOR_cmp(const X509_ALGOR *a, const X509_ALGOR *b)
  88 {
  89     int rv;
  90     rv = OBJ_cmp(a->algorithm, b->algorithm);
  91     if (rv)
  92         return rv;
  93     if (!a->parameter && !b->parameter)
  94         return 0;
  95     return ASN1_TYPE_cmp(a->parameter, b->parameter);
  96 }
  97
  98 int X509_ALGOR_copy(X509_ALGOR *dest, const X509_ALGOR *src)
  99 {
 100     if (src == NULL || dest == NULL)
 101         return 0;
 102
 103     if (dest->algorithm)
 104          ASN1_OBJECT_free(dest->algorithm);
 105     dest->algorithm = NULL;
 106
 107     if (dest->parameter)
 108         ASN1_TYPE_free(dest->parameter);
 109     dest->parameter = NULL;
 110
 111     if (src->algorithm)
 112         if ((dest->algorithm = OBJ_dup(src->algorithm)) == NULL)
 113             return 0;
 114
 115     if (src->parameter != NULL) {
 116         dest->parameter = ASN1_TYPE_new();
 117         if (dest->parameter == NULL)
 118             return 0;
 119
 120         /* Assuming this is also correct for a BOOL.
 121          * set does copy as a side effect.
 122          */
 123         if (ASN1_TYPE_set1(dest->parameter,
 124               src->parameter->type, src->parameter->value.ptr) == 0)
 125             return 0;
 126     }
 127
 128     return 1;
 129 }
 130
 131 /* allocate and set algorithm ID from EVP_MD, default SHA1 */
 132 int ossl_x509_algor_new_from_md(X509_ALGOR **palg, const EVP_MD *md)
 133 {
 134     /* Default is SHA1 so no need to create it - still success */
 135     if (md == NULL || EVP_MD_is_a(md, "SHA1"))
 136         return 1;
 137     *palg = X509_ALGOR_new();
 138     if (*palg == NULL)
 139         return 0;
 140     X509_ALGOR_set_md(*palg, md);
 141     return 1;
 142 }
 143
 144 /* convert algorithm ID to EVP_MD, default SHA1 */
 145 const EVP_MD *ossl_x509_algor_get_md(X509_ALGOR *alg)
 146 {
 147     const EVP_MD *md;
 148
 149     if (alg == NULL)
 150         return EVP_sha1();
 151     md = EVP_get_digestbyobj(alg->algorithm);
 152     if (md == NULL)
 153         ERR_raise(ERR_LIB_ASN1, ASN1_R_UNKNOWN_DIGEST);
 154     return md;
 155 }
 156
 157 X509_ALGOR *ossl_x509_algor_mgf1_decode(X509_ALGOR *alg)
 158 {
 159     if (OBJ_obj2nid(alg->algorithm) != NID_mgf1)
 160         return NULL;
 161     return ASN1_TYPE_unpack_sequence(ASN1_ITEM_rptr(X509_ALGOR),
 162                                      alg->parameter);
 163 }
 164
 165 /* Allocate and set MGF1 algorithm ID from EVP_MD */
 166 int ossl_x509_algor_md_to_mgf1(X509_ALGOR **palg, const EVP_MD *mgf1md)
 167 {
 168     X509_ALGOR *algtmp = NULL;
 169     ASN1_STRING *stmp = NULL;
 170
 171     *palg = NULL;
 172     if (mgf1md == NULL || EVP_MD_is_a(mgf1md, "SHA1"))
 173         return 1;
 174     /* need to embed algorithm ID inside another */
 175     if (!ossl_x509_algor_new_from_md(&algtmp, mgf1md))
 176         goto err;
 177     if (ASN1_item_pack(algtmp, ASN1_ITEM_rptr(X509_ALGOR), &stmp) == NULL)
 178          goto err;
 179     *palg = X509_ALGOR_new();
 180     if (*palg == NULL)
 181         goto err;
 182     X509_ALGOR_set0(*palg, OBJ_nid2obj(NID_mgf1), V_ASN1_SEQUENCE, stmp);
 183     stmp = NULL;
 184  err:
 185     ASN1_STRING_free(stmp);
 186     X509_ALGOR_free(algtmp);
 187     if (*palg != NULL)
 188         return 1;
 189     return 0;
 190 }