/* SPDX-License-Identifier: GPL-2.0 */ /* * NIST SP800-90A DRBG derivation function * * Copyright (C) 2014, Stephan Mueller <smueller@chronox.de> */ #ifndef _INTERNAL_DRBG_H #define _INTERNAL_DRBG_H /* * Convert an integer into a byte representation of this integer. * The byte representation is big-endian * * @val value to be converted * @buf buffer holding the converted integer -- caller must ensure that * buffer size is at least 32 bit */ static inline void drbg_cpu_to_be32(__u32 val, unsigned char *buf) { struct s { __be32 conv; }; struct s *conversion = (struct s *)buf; conversion->conv = cpu_to_be32(val); } /* * Concatenation Helper and string operation helper * * SP800-90A requires the concatenation of different data. To avoid copying * buffers around or allocate additional memory, the following data structure * is used to point to the original memory with its size. In addition, it * is used to build a linked list. The linked list defines the concatenation * of individual buffers. The order of memory block referenced in that * linked list determines the order of concatenation. */ struct drbg_string { const unsigned char *buf; size_t len; struct list_head list; }; static inline void drbg_string_fill(struct drbg_string *string, const unsigned char *buf, size_t len) { string->buf = buf; string->len = len; INIT_LIST_HEAD(&string->list); } #endif //_INTERNAL_DRBG_H