1 /* $OpenBSD: hm_ameth.c,v 1.12 2021/12/12 21:30:14 tb Exp $ */ 2 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL 3 * project 2007. 4 */ 5 /* ==================================================================== 6 * Copyright (c) 2007 The OpenSSL Project. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in 17 * the documentation and/or other materials provided with the 18 * distribution. 19 * 20 * 3. All advertising materials mentioning features or use of this 21 * software must display the following acknowledgment: 22 * "This product includes software developed by the OpenSSL Project 23 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" 24 * 25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 26 * endorse or promote products derived from this software without 27 * prior written permission. For written permission, please contact 28 * licensing@OpenSSL.org. 29 * 30 * 5. Products derived from this software may not be called "OpenSSL" 31 * nor may "OpenSSL" appear in their names without prior written 32 * permission of the OpenSSL Project. 33 * 34 * 6. Redistributions of any form whatsoever must retain the following 35 * acknowledgment: 36 * "This product includes software developed by the OpenSSL Project 37 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" 38 * 39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 42 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 50 * OF THE POSSIBILITY OF SUCH DAMAGE. 51 * ==================================================================== 52 * 53 * This product includes cryptographic software written by Eric Young 54 * (eay@cryptsoft.com). This product includes software written by Tim 55 * Hudson (tjh@cryptsoft.com). 56 * 57 */ 58 59 #include <stdio.h> 60 #include <string.h> 61 62 #include <openssl/evp.h> 63 #include <openssl/hmac.h> 64 65 #include "asn1_locl.h" 66 #include "evp_locl.h" 67 #include "hmac_local.h" 68 69 #define HMAC_TEST_PRIVATE_KEY_FORMAT 70 71 /* HMAC "ASN1" method. This is just here to indicate the 72 * maximum HMAC output length and to free up an HMAC 73 * key. 74 */ 75 76 static int 77 hmac_size(const EVP_PKEY *pkey) 78 { 79 return EVP_MAX_MD_SIZE; 80 } 81 82 static void 83 hmac_key_free(EVP_PKEY *pkey) 84 { 85 ASN1_OCTET_STRING *os = (ASN1_OCTET_STRING *)pkey->pkey.ptr; 86 87 if (os) { 88 if (os->data) 89 explicit_bzero(os->data, os->length); 90 ASN1_OCTET_STRING_free(os); 91 } 92 } 93 94 static int 95 hmac_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2) 96 { 97 switch (op) { 98 case ASN1_PKEY_CTRL_DEFAULT_MD_NID: 99 *(int *)arg2 = NID_sha1; 100 return 1; 101 default: 102 return -2; 103 } 104 } 105 106 #ifdef HMAC_TEST_PRIVATE_KEY_FORMAT 107 /* A bogus private key format for test purposes. This is simply the 108 * HMAC key with "HMAC PRIVATE KEY" in the headers. When enabled the 109 * genpkey utility can be used to "generate" HMAC keys. 110 */ 111 112 static int 113 old_hmac_decode(EVP_PKEY *pkey, const unsigned char **pder, int derlen) 114 { 115 ASN1_OCTET_STRING *os; 116 117 os = ASN1_OCTET_STRING_new(); 118 if (os == NULL) 119 goto err; 120 if (ASN1_OCTET_STRING_set(os, *pder, derlen) == 0) 121 goto err; 122 if (EVP_PKEY_assign(pkey, EVP_PKEY_HMAC, os) == 0) 123 goto err; 124 return 1; 125 126 err: 127 ASN1_OCTET_STRING_free(os); 128 return 0; 129 } 130 131 static int 132 old_hmac_encode(const EVP_PKEY *pkey, unsigned char **pder) 133 { 134 int inc; 135 ASN1_OCTET_STRING *os = (ASN1_OCTET_STRING *)pkey->pkey.ptr; 136 137 if (pder) { 138 if (!*pder) { 139 *pder = malloc(os->length); 140 if (*pder == NULL) 141 return -1; 142 inc = 0; 143 } else 144 inc = 1; 145 146 memcpy(*pder, os->data, os->length); 147 148 if (inc) 149 *pder += os->length; 150 } 151 152 return os->length; 153 } 154 155 #endif 156 157 const EVP_PKEY_ASN1_METHOD hmac_asn1_meth = { 158 .pkey_id = EVP_PKEY_HMAC, 159 .pkey_base_id = EVP_PKEY_HMAC, 160 161 .pem_str = "HMAC", 162 .info = "OpenSSL HMAC method", 163 164 .pkey_size = hmac_size, 165 166 .pkey_free = hmac_key_free, 167 .pkey_ctrl = hmac_pkey_ctrl, 168 #ifdef HMAC_TEST_PRIVATE_KEY_FORMAT 169 .old_priv_decode = old_hmac_decode, 170 .old_priv_encode = old_hmac_encode 171 #endif 172 }; 173