crypto/siphash/siphash_ameth.c

   1 /*
   2  * Copyright 2007-2017 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the OpenSSL license (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 "internal/cryptlib.h"
  12 #include <openssl/evp.h>
  13 #include "internal/asn1_int.h"
  14 #include "internal/siphash.h"
  15 #include "siphash_local.h"
  16 #include "internal/evp_int.h"
  17
  18 /*
  19  * SIPHASH "ASN1" method. This is just here to indicate the maximum
  20  * SIPHASH output length and to free up a SIPHASH key.
  21  */
  22
  23 static int siphash_size(const EVP_PKEY *pkey)
  24 {
  25     return SIPHASH_MAX_DIGEST_SIZE;
  26 }
  27
  28 static void siphash_key_free(EVP_PKEY *pkey)
  29 {
  30     ASN1_OCTET_STRING *os = EVP_PKEY_get0(pkey);
  31
  32     if (os != NULL) {
  33         if (os->data != NULL)
  34             OPENSSL_cleanse(os->data, os->length);
  35         ASN1_OCTET_STRING_free(os);
  36     }
  37 }
  38
  39 static int siphash_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2)
  40 {
  41     /* nothing (including ASN1_PKEY_CTRL_DEFAULT_MD_NID), is supported */
  42     return -2;
  43 }
  44
  45 static int siphash_pkey_public_cmp(const EVP_PKEY *a, const EVP_PKEY *b)
  46 {
  47     return ASN1_OCTET_STRING_cmp(EVP_PKEY_get0(a), EVP_PKEY_get0(b));
  48 }
  49
  50 static int siphash_set_priv_key(EVP_PKEY *pkey, const unsigned char *priv,
  51                                 size_t len)
  52 {
  53     ASN1_OCTET_STRING *os;
  54
  55     if (pkey->pkey.ptr != NULL || len != SIPHASH_KEY_SIZE)
  56         return 0;
  57
  58     os = ASN1_OCTET_STRING_new();
  59     if (os == NULL)
  60         return 0;
  61
  62     if (!ASN1_OCTET_STRING_set(os, priv, len)) {
  63         ASN1_OCTET_STRING_free(os);
  64         return 0;
  65     }
  66
  67     pkey->pkey.ptr = os;
  68     return 1;
  69 }
  70
  71 const EVP_PKEY_ASN1_METHOD siphash_asn1_meth = {
  72     EVP_PKEY_SIPHASH,
  73     EVP_PKEY_SIPHASH,
  74     0,
  75
  76     "SIPHASH",
  77     "OpenSSL SIPHASH method",
  78
  79     0, 0, siphash_pkey_public_cmp, 0,
  80
  81     0, 0, 0,
  82
  83     siphash_size,
  84     0, 0,
  85     0, 0, 0, 0, 0, 0, 0,
  86
  87     siphash_key_free,
  88     siphash_pkey_ctrl,
  89     NULL,
  90     NULL,
  91
  92     NULL,
  93     NULL,
  94     NULL,
  95
  96     NULL,
  97     NULL,
  98     NULL,
  99
 100     siphash_set_priv_key,
 101     NULL,
 102 };