1 #ifndef _IPXE_CBC_H
2 #define _IPXE_CBC_H
3
4 /** @file
5 *
6 * Cipher-block chaining
7 *
8 */
9
10 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
11
12 #include <ipxe/crypto.h>
13
14 /**
15 * Set key
16 *
17 * @v ctx Context
18 * @v key Key
19 * @v keylen Key length
20 * @v raw_cipher Underlying cipher algorithm
21 * @v cbc_ctx CBC context
22 * @ret rc Return status code
23 */
cbc_setkey(void * ctx,const void * key,size_t keylen,struct cipher_algorithm * raw_cipher,void * cbc_ctx __unused)24 static inline int cbc_setkey ( void *ctx, const void *key, size_t keylen,
25 struct cipher_algorithm *raw_cipher,
26 void *cbc_ctx __unused ) {
27
28 return cipher_setkey ( raw_cipher, ctx, key, keylen );
29 }
30
31 /**
32 * Set initialisation vector
33 *
34 * @v ctx Context
35 * @v iv Initialisation vector
36 * @v raw_cipher Underlying cipher algorithm
37 * @v cbc_ctx CBC context
38 */
cbc_setiv(void * ctx __unused,const void * iv,struct cipher_algorithm * raw_cipher,void * cbc_ctx)39 static inline void cbc_setiv ( void *ctx __unused, const void *iv,
40 struct cipher_algorithm *raw_cipher,
41 void *cbc_ctx ) {
42 memcpy ( cbc_ctx, iv, raw_cipher->blocksize );
43 }
44
45 extern void cbc_encrypt ( void *ctx, const void *src, void *dst,
46 size_t len, struct cipher_algorithm *raw_cipher,
47 void *cbc_ctx );
48 extern void cbc_decrypt ( void *ctx, const void *src, void *dst,
49 size_t len, struct cipher_algorithm *raw_cipher,
50 void *cbc_ctx );
51
52 /**
53 * Create a cipher-block chaining mode of behaviour of an existing cipher
54 *
55 * @v _cbc_name Name for the new CBC cipher
56 * @v _cbc_cipher New cipher algorithm
57 * @v _raw_cipher Underlying cipher algorithm
58 * @v _raw_context Context structure for the underlying cipher
59 * @v _blocksize Cipher block size
60 */
61 #define CBC_CIPHER( _cbc_name, _cbc_cipher, _raw_cipher, _raw_context, \
62 _blocksize ) \
63 struct _cbc_name ## _context { \
64 _raw_context raw_ctx; \
65 uint8_t cbc_ctx[_blocksize]; \
66 }; \
67 static int _cbc_name ## _setkey ( void *ctx, const void *key, \
68 size_t keylen ) { \
69 struct _cbc_name ## _context * _cbc_name ## _ctx = ctx; \
70 return cbc_setkey ( &_cbc_name ## _ctx->raw_ctx, key, keylen, \
71 &_raw_cipher, &_cbc_name ## _ctx->cbc_ctx );\
72 } \
73 static void _cbc_name ## _setiv ( void *ctx, const void *iv ) { \
74 struct _cbc_name ## _context * _cbc_name ## _ctx = ctx; \
75 cbc_setiv ( &_cbc_name ## _ctx->raw_ctx, iv, \
76 &_raw_cipher, &aes_cbc_ctx->cbc_ctx ); \
77 } \
78 static void _cbc_name ## _encrypt ( void *ctx, const void *src, \
79 void *dst, size_t len ) { \
80 struct _cbc_name ## _context * _cbc_name ## _ctx = ctx; \
81 cbc_encrypt ( &_cbc_name ## _ctx->raw_ctx, src, dst, len, \
82 &_raw_cipher, &aes_cbc_ctx->cbc_ctx ); \
83 } \
84 static void _cbc_name ## _decrypt ( void *ctx, const void *src, \
85 void *dst, size_t len ) { \
86 struct _cbc_name ## _context * _cbc_name ## _ctx = ctx; \
87 cbc_decrypt ( &_cbc_name ## _ctx->raw_ctx, src, dst, len, \
88 &_raw_cipher, &aes_cbc_ctx->cbc_ctx ); \
89 } \
90 struct cipher_algorithm _cbc_cipher = { \
91 .name = #_cbc_name, \
92 .ctxsize = sizeof ( struct _cbc_name ## _context ), \
93 .blocksize = _blocksize, \
94 .setkey = _cbc_name ## _setkey, \
95 .setiv = _cbc_name ## _setiv, \
96 .encrypt = _cbc_name ## _encrypt, \
97 .decrypt = _cbc_name ## _decrypt, \
98 };
99
100 #endif /* _IPXE_CBC_H */
101