1 /* ==================================================================== 2 * Copyright (c) 2001-2011 The OpenSSL Project. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in 13 * the documentation and/or other materials provided with the 14 * distribution. 15 * 16 * 3. All advertising materials mentioning features or use of this 17 * software must display the following acknowledgment: 18 * "This product includes software developed by the OpenSSL Project 19 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" 20 * 21 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 22 * endorse or promote products derived from this software without 23 * prior written permission. For written permission, please contact 24 * openssl-core (at) openssl.org. 25 * 26 * 5. Products derived from this software may not be called "OpenSSL" 27 * nor may "OpenSSL" appear in their names without prior written 28 * permission of the OpenSSL Project. 29 * 30 * 6. Redistributions of any form whatsoever must retain the following 31 * acknowledgment: 32 * "This product includes software developed by the OpenSSL Project 33 * for use in the OpenSSL Toolkit (http://www.openssl.org/)" 34 * 35 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 36 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 37 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 38 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 39 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 40 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 41 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 42 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 43 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 44 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 45 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 46 * OF THE POSSIBILITY OF SUCH DAMAGE. 47 * ==================================================================== */ 48 49 #include <openssl/aes.h> 50 51 #include <limits.h> 52 #include <string.h> 53 54 #include <openssl/mem.h> 55 56 #include "../../internal.h" 57 58 59 // kDefaultIV is the default IV value given in RFC 3394, 2.2.3.1. 60 static const uint8_t kDefaultIV[] = { 61 0xa6, 0xa6, 0xa6, 0xa6, 0xa6, 0xa6, 0xa6, 0xa6, 62 }; 63 64 static const unsigned kBound = 6; 65 66 int AES_wrap_key(const AES_KEY *key, const uint8_t *iv, uint8_t *out, 67 const uint8_t *in, size_t in_len) { 68 // See RFC 3394, section 2.2.1. 69 70 if (in_len > INT_MAX - 8 || in_len < 8 || in_len % 8 != 0) { 71 return -1; 72 } 73 74 if (iv == NULL) { 75 iv = kDefaultIV; 76 } 77 78 OPENSSL_memmove(out + 8, in, in_len); 79 uint8_t A[AES_BLOCK_SIZE]; 80 OPENSSL_memcpy(A, iv, 8); 81 82 size_t n = in_len / 8; 83 84 for (unsigned j = 0; j < kBound; j++) { 85 for (size_t i = 1; i <= n; i++) { 86 OPENSSL_memcpy(A + 8, out + 8 * i, 8); 87 AES_encrypt(A, A, key); 88 89 uint32_t t = (uint32_t)(n * j + i); 90 A[7] ^= t & 0xff; 91 A[6] ^= (t >> 8) & 0xff; 92 A[5] ^= (t >> 16) & 0xff; 93 A[4] ^= (t >> 24) & 0xff; 94 OPENSSL_memcpy(out + 8 * i, A + 8, 8); 95 } 96 } 97 98 OPENSSL_memcpy(out, A, 8); 99 return (int)in_len + 8; 100 } 101 102 int AES_unwrap_key(const AES_KEY *key, const uint8_t *iv, uint8_t *out, 103 const uint8_t *in, size_t in_len) { 104 // See RFC 3394, section 2.2.2. 105 106 if (in_len > INT_MAX || in_len < 16 || in_len % 8 != 0) { 107 return -1; 108 } 109 110 if (iv == NULL) { 111 iv = kDefaultIV; 112 } 113 114 uint8_t A[AES_BLOCK_SIZE]; 115 OPENSSL_memcpy(A, in, 8); 116 OPENSSL_memmove(out, in + 8, in_len - 8); 117 118 size_t n = (in_len / 8) - 1; 119 120 for (unsigned j = kBound - 1; j < kBound; j--) { 121 for (size_t i = n; i > 0; i--) { 122 uint32_t t = (uint32_t)(n * j + i); 123 A[7] ^= t & 0xff; 124 A[6] ^= (t >> 8) & 0xff; 125 A[5] ^= (t >> 16) & 0xff; 126 A[4] ^= (t >> 24) & 0xff; 127 OPENSSL_memcpy(A + 8, out + 8 * (i - 1), 8); 128 AES_decrypt(A, A, key); 129 OPENSSL_memcpy(out + 8 * (i - 1), A + 8, 8); 130 } 131 } 132 133 if (CRYPTO_memcmp(A, iv, 8) != 0) { 134 return -1; 135 } 136 137 return (int)in_len - 8; 138 } 139
