crypto/rsa/rsa_schemes.c

   1 /*
   2  * Copyright 2020 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 <openssl/core.h>
  11 #include <openssl/core_names.h>
  12 #include <openssl/evp.h>
  13 #include <openssl/obj_mac.h>
  14 #include "internal/nelem.h"
  15 #include "crypto/rsa.h"
  16
  17 static int meth2nid(const void *meth,
  18                     int (*meth_is_a)(const void *meth, const char *name),
  19                     const OSSL_ITEM *items, size_t items_n)
  20 {
  21     size_t i;
  22
  23     if (meth != NULL)
  24         for (i = 0; i < items_n; i++)
  25             if (meth_is_a(meth, items[i].ptr))
  26                 return (int)items[i].id;
  27     return NID_undef;
  28 }
  29
  30 static const char *nid2name(int meth, const OSSL_ITEM *items, size_t items_n)
  31 {
  32     size_t i;
  33
  34     for (i = 0; i < items_n; i++)
  35         if (meth == (int)items[i].id)
  36             return items[i].ptr;
  37     return NULL;
  38 }
  39
  40 /*
  41  * The list of permitted hash functions are taken from
  42  * https://tools.ietf.org/html/rfc8017#appendix-A.2.1:
  43  *
  44  * OAEP-PSSDigestAlgorithms    ALGORITHM-IDENTIFIER ::= {
  45  *     { OID id-sha1       PARAMETERS NULL }|
  46  *     { OID id-sha224     PARAMETERS NULL }|
  47  *     { OID id-sha256     PARAMETERS NULL }|
  48  *     { OID id-sha384     PARAMETERS NULL }|
  49  *     { OID id-sha512     PARAMETERS NULL }|
  50  *     { OID id-sha512-224 PARAMETERS NULL }|
  51  *     { OID id-sha512-256 PARAMETERS NULL },
  52  *     ...  -- Allows for future expansion --
  53  * }
  54  */
  55 static const OSSL_ITEM oaeppss_name_nid_map[] = {
  56     { NID_sha1,         OSSL_DIGEST_NAME_SHA1         },
  57     { NID_sha224,       OSSL_DIGEST_NAME_SHA2_224     },
  58     { NID_sha256,       OSSL_DIGEST_NAME_SHA2_256     },
  59     { NID_sha384,       OSSL_DIGEST_NAME_SHA2_384     },
  60     { NID_sha512,       OSSL_DIGEST_NAME_SHA2_512     },
  61     { NID_sha512_224,   OSSL_DIGEST_NAME_SHA2_512_224 },
  62     { NID_sha512_256,   OSSL_DIGEST_NAME_SHA2_512_256 },
  63 };
  64
  65 static int md_is_a(const void *md, const char *name)
  66 {
  67     return EVP_MD_is_a(md, name);
  68 }
  69
  70 int rsa_oaeppss_md2nid(const EVP_MD *md)
  71 {
  72     return meth2nid(md, md_is_a,
  73                     oaeppss_name_nid_map, OSSL_NELEM(oaeppss_name_nid_map));
  74 }
  75
  76 const char *rsa_oaeppss_nid2name(int md)
  77 {
  78     return nid2name(md, oaeppss_name_nid_map, OSSL_NELEM(oaeppss_name_nid_map));
  79 }
  80
  81 const char *rsa_mgf_nid2name(int mgf)
  82 {
  83     if (mgf == NID_mgf1)
  84         return SN_mgf1;
  85     return NULL;
  86 }