xref: /xnu-8020.101.4/libkern/libkern/crypto/aesxts.h (revision e7776783b89a353188416a9a346c6cdb4928faad) !
1 /*
2  * Copyright (c) 2012 Apple Computer, Inc. All rights reserved.
3  *
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8  * Version 2.0 (the 'License'). You may not use this file except in
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15  * Please obtain a copy of the License at
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27  */
28 
29 #ifndef _CRYPTO_AESXTS_H
30 #define _CRYPTO_AESXTS_H
31 
32 #if defined(__cplusplus)
33 extern "C"
34 {
35 #endif
36 
37 #include <corecrypto/ccmode.h>
38 #include <corecrypto/ccaes.h>
39 #include <corecrypto/ccn.h>
40 
41 //Unholy HACK: this works because we know the size of the context for every
42 //possible corecrypto implementation is less than this.
43 #define AES_XTS_CTX_MAX_SIZE (ccn_sizeof_size(3*sizeof(void *)) + 2*ccn_sizeof_size(128*4) + ccn_sizeof_size(16))
44 
45 typedef struct {
46 	ccxts_ctx_decl(AES_XTS_CTX_MAX_SIZE, enc);
47 	ccxts_ctx_decl(AES_XTS_CTX_MAX_SIZE, dec);
48 } symmetric_xts;
49 
50 
51 /*
52  * These are the interfaces required for XTS-AES support
53  */
54 
55 uint32_t
56 xts_start(uint32_t cipher, // ignored - we're doing this for xts-aes only
57     const uint8_t *IV,               // ignored
58     const uint8_t *key1, int keylen,
59     const uint8_t *key2, int tweaklen,               // both keys are the same size for xts
60     uint32_t num_rounds,               // ignored
61     uint32_t options,                  // ignored
62     symmetric_xts *xts);
63 
64 int xts_encrypt(const uint8_t *pt, unsigned long ptlen,
65     uint8_t *ct,
66     const uint8_t *tweak,                             // this can be considered the sector IV for this use
67     symmetric_xts *xts);
68 
69 int xts_decrypt(const uint8_t *ct, unsigned long ptlen,
70     uint8_t *pt,
71     const uint8_t *tweak,                             // this can be considered the sector IV for this use
72     symmetric_xts *xts);
73 
74 void xts_done(symmetric_xts *xts);
75 
76 #if defined(__cplusplus)
77 }
78 #endif
79 
80 #endif
81