1/*
2 * Copyright (c) 2010 Apple Inc. All Rights Reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. Please obtain a copy of the License at
10 * http://www.opensource.apple.com/apsl/ and read it before using this
11 * file.
12 *
13 * The Original Code and all software distributed under the License are
14 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
15 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
16 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
18 * Please see the License for the specific language governing rights and
19 * limitations under the License.
20 *
21 * @APPLE_LICENSE_HEADER_END@
22 */
23
24#ifndef _CC_SYMKEYWRAP_H_
25#define _CC_SYMKEYWRAP_H_
26
27#include <sys/types.h>
28#include <stdint.h>
29
30#include <string.h>
31#include <limits.h>
32#include <stdlib.h>
33
34#if defined(_MSC_VER)
35#include <availability.h>
36#else
37#include <os/availability.h>
38#endif
39
40
41#ifdef __cplusplus
42extern "C" {
43#endif
44
45enum {
46 kCCWRAPAES = 1,
47};
48
49extern const uint8_t * const CCrfc3394_iv API_AVAILABLE(macos(10.7), ios(5.0));
50extern const size_t CCrfc3394_ivLen API_AVAILABLE(macos(10.7), ios(5.0));
51
52typedef uint32_t CCWrappingAlgorithm;
53
54/*!
55 @function CCSymmetricKeyWrap
56 @abstract Wrap a symmetric key with a Key Encryption Key (KEK).
57
58 @param algorithm Currently only AES Keywrapping (rfc3394) is available
59 via kCCWRAPAES
60 @param iv The initialization value to be used. CCrfc3394_iv is
61 available as a constant for the standard IV to use.
62 @param ivLen The length of the initialization value to be used.
63 CCrfc3394_ivLen is available as a constant for the
64 standard IV to use.
65 @param kek The Key Encryption Key to be used to wrap the raw key.
66 @param kekLen The length of the KEK in bytes.
67 @param rawKey The raw key bytes to be wrapped.
68 @param rawKeyLen The length of the key in bytes.
69 @param wrappedKey The resulting wrapped key produced by the function.
70 The space for this must be provided by the caller.
71 @param wrappedKeyLen The length of the wrapped key in bytes.
72
73 @discussion The algorithm chosen is determined by the algorithm parameter
74 and the size of the key being wrapped (ie aes128 for 128 bit
75 keys).
76
77 @result kCCBufferTooSmall indicates insufficent space in the wrappedKey
78 buffer.
79 kCCParamError can result from bad values for the kek, rawKey, and
80 wrappedKey key pointers.
81 */
82
83int
84CCSymmetricKeyWrap(CCWrappingAlgorithm algorithm,
85 const uint8_t *iv, const size_t ivLen,
86 const uint8_t *kek, size_t kekLen,
87 const uint8_t *rawKey, size_t rawKeyLen,
88 uint8_t *wrappedKey, size_t *wrappedKeyLen)
89 API_AVAILABLE(macos(10.7), ios(5.0));
90
91/*!
92 @function CCSymmetricKeyUnwrap
93 @abstract Unwrap a symmetric key with a Key Encryption Key (KEK).
94
95 @param algorithm Currently only AES Keywrapping (rfc3394) is available
96 via kCCWRAPAES
97 @param iv The initialization value to be used. CCrfc3394_iv is
98 available as a constant for the standard IV to use.
99 @param ivLen The length of the initialization value to be used.
100 CCrfc3394_ivLen is available as a constant for the
101 standard IV to use.
102 @param kek The Key Encryption Key to be used to unwrap the raw key.
103 @param kekLen The length of the KEK in bytes.
104 @param wrappedKey The wrapped key bytes.
105 @param wrappedKeyLen The length of the wrapped key in bytes.
106 @param rawKey The resulting raw key bytes. The space for this must
107 be provided by the caller.
108 @param rawKeyLen The length of the raw key in bytes.
109
110 @discussion The algorithm chosen is determined by the algorithm parameter
111 and the size of the key being wrapped (ie aes128 for 128 bit
112 keys).
113
114 @result kCCBufferTooSmall indicates insufficent space in the rawKey buffer.
115 kCCParamError can result from bad values for the kek, rawKey, and
116 wrappedKey key pointers.
117 */
118
119
120int
121CCSymmetricKeyUnwrap(CCWrappingAlgorithm algorithm,
122 const uint8_t *iv, const size_t ivLen,
123 const uint8_t *kek, size_t kekLen,
124 const uint8_t *wrappedKey, size_t wrappedKeyLen,
125 uint8_t *rawKey, size_t *rawKeyLen)
126 API_AVAILABLE(macos(10.7), ios(5.0));
127
128/*!
129 @function CCSymmetricWrappedSize
130 @abstract Determine the buffer size required to hold a key wrapped with
131 CCAESKeyWrap().
132
133 @param algorithm Currently only AES Keywrapping (rfc3394) is
134 available via kCCWRAPAES
135 @param rawKeyLen The length of the key in bytes.
136 @result The length of the resulting wrapped key.
137 */
138
139size_t
140CCSymmetricWrappedSize(CCWrappingAlgorithm algorithm, size_t rawKeyLen)
141API_AVAILABLE(macos(10.7), ios(5.0));
142
143/*!
144 @function CCSymmetricUnwrappedSize
145 @abstract Determine the buffer size required to hold a key unwrapped with
146 CCAESKeyUnwrap().
147
148 @param algorithm Currently only AES Keywrapping (rfc3394) is
149 available via kCCWRAPAES
150 @param wrappedKeyLen The length of the wrapped key in bytes.
151 @result The length of the resulting raw key.
152 */
153
154size_t
155CCSymmetricUnwrappedSize(CCWrappingAlgorithm algorithm, size_t wrappedKeyLen)
156API_AVAILABLE(macos(10.7), ios(5.0));
157
158#ifdef __cplusplus
159}
160#endif
161
162#endif /* _CC_SYMKEYWRAP_H_ */