1 | /* Copyright (c) (2021,2022) Apple Inc. All rights reserved. |
2 | * |
3 | * corecrypto is licensed under Apple Inc.’s Internal Use License Agreement (which |
4 | * is contained in the License.txt file distributed with corecrypto) and only to |
5 | * people who accept that license. IMPORTANT: Any license rights granted to you by |
6 | * Apple Inc. (if any) are limited to internal use within your organization only on |
7 | * devices and computers you own or control, for the sole purpose of verifying the |
8 | * security characteristics and correct functioning of the Apple Software. You may |
9 | * not, directly or indirectly, redistribute the Apple Software or any portions thereof. |
10 | */ |
11 | |
12 | #ifndef _CORECRYPTO_CCDRBG_DF_H_ |
13 | #define _CORECRYPTO_CCDRBG_DF_H_ |
14 | |
15 | #include <corecrypto/cc.h> |
16 | #include <corecrypto/ccmode_impl.h> |
17 | |
18 | // This is an interface for derivation functions for DRBGs to convert |
19 | // high-entropy inputs into key material. Because this interface is |
20 | // intended for internal usage, we declare only the type names and |
21 | // initialization functions here. |
22 | |
23 | typedef struct ccdrbg_df_ctx ccdrbg_df_ctx_t; |
24 | |
25 | struct ccdrbg_df_ctx { |
26 | int (*derive_keys)(const ccdrbg_df_ctx_t *ctx, |
27 | size_t inputs_count, |
28 | const cc_iovec_t *inputs, |
29 | size_t keys_nbytes, |
30 | void *keys); |
31 | }; |
32 | |
33 | // This is a block-cipher-based instantiation of the derivation |
34 | // function for use in the CTR-DRBG. |
35 | |
36 | typedef struct ccdrbg_df_bc_ctx ccdrbg_df_bc_ctx_t; |
37 | |
38 | struct ccdrbg_df_bc_ctx { |
39 | ccdrbg_df_ctx_t df_ctx; |
40 | const struct ccmode_cbc *cbc_info; |
41 | size_t key_nbytes; |
42 | |
43 | // See ccmode_impl.h. |
44 | cc_ctx_decl_field(cccbc_ctx, CCCBC_MAX_CTX_SIZE, cbc_ctx); |
45 | }; |
46 | |
47 | /*! |
48 | @function ccdrbg_df_bc_init |
49 | @abstract Initialize a block-cipher-based derivation function |
50 | @param ctx The derivation function context |
51 | @param cbc_info A descriptor for a CBC mode of a block cipher |
52 | @param key_nbytes The length of the key to use in the derivation function |
53 | |
54 | @discussion Note that a fixed key is used internally, so only the |
55 | key length needs to be specified. |
56 | @return 0 if successful; negative otherwise |
57 | */ |
58 | CC_WARN_RESULT |
59 | CC_NONNULL_ALL |
60 | int ccdrbg_df_bc_init(ccdrbg_df_bc_ctx_t *ctx, |
61 | const struct ccmode_cbc *cbc_info, |
62 | size_t key_nbytes); |
63 | |
64 | #endif /* _CORECRYPTO_CCDRBG_DF_H_ */ |
65 | |