blake2s.h

  1/* SPDX-License-Identifier: GPL-2.0 OR MIT */
  2/*
  3 * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
  4 */
  5
  6#ifndef _CRYPTO_BLAKE2S_H
  7#define _CRYPTO_BLAKE2S_H
  8
  9#include <linux/bug.h>
 10#include <linux/kconfig.h>
 11#include <linux/types.h>
 12#include <linux/string.h>
 13
 14enum blake2s_lengths {
 15	BLAKE2S_BLOCK_SIZE = 64,
 16	BLAKE2S_HASH_SIZE = 32,
 17	BLAKE2S_KEY_SIZE = 32,
 18
 19	BLAKE2S_128_HASH_SIZE = 16,
 20	BLAKE2S_160_HASH_SIZE = 20,
 21	BLAKE2S_224_HASH_SIZE = 28,
 22	BLAKE2S_256_HASH_SIZE = 32,
 23};
 24
 25/**
 26 * struct blake2s_ctx - Context for hashing a message with BLAKE2s
 27 * @h: compression function state
 28 * @t: block counter
 29 * @f: finalization indicator
 30 * @buf: partial block buffer; 'buflen' bytes are valid
 31 * @buflen: number of bytes buffered in @buf
 32 * @outlen: length of output hash value in bytes, at most BLAKE2S_HASH_SIZE
 33 */
 34struct blake2s_ctx {
 35	/* 'h', 't', and 'f' are used in assembly code, so keep them as-is. */
 36	u32 h[8];
 37	u32 t[2];
 38	u32 f[2];
 39	u8 buf[BLAKE2S_BLOCK_SIZE];
 40	unsigned int buflen;
 41	unsigned int outlen;
 42};
 43
 44enum blake2s_iv {
 45	BLAKE2S_IV0 = 0x6A09E667UL,
 46	BLAKE2S_IV1 = 0xBB67AE85UL,
 47	BLAKE2S_IV2 = 0x3C6EF372UL,
 48	BLAKE2S_IV3 = 0xA54FF53AUL,
 49	BLAKE2S_IV4 = 0x510E527FUL,
 50	BLAKE2S_IV5 = 0x9B05688CUL,
 51	BLAKE2S_IV6 = 0x1F83D9ABUL,
 52	BLAKE2S_IV7 = 0x5BE0CD19UL,
 53};
 54
 55static inline void __blake2s_init(struct blake2s_ctx *ctx, size_t outlen,
 56				  const void *key, size_t keylen)
 57{
 58	ctx->h[0] = BLAKE2S_IV0 ^ (0x01010000 | keylen << 8 | outlen);
 59	ctx->h[1] = BLAKE2S_IV1;
 60	ctx->h[2] = BLAKE2S_IV2;
 61	ctx->h[3] = BLAKE2S_IV3;
 62	ctx->h[4] = BLAKE2S_IV4;
 63	ctx->h[5] = BLAKE2S_IV5;
 64	ctx->h[6] = BLAKE2S_IV6;
 65	ctx->h[7] = BLAKE2S_IV7;
 66	ctx->t[0] = 0;
 67	ctx->t[1] = 0;
 68	ctx->f[0] = 0;
 69	ctx->f[1] = 0;
 70	ctx->buflen = 0;
 71	ctx->outlen = outlen;
 72	if (keylen) {
 73		memcpy(ctx->buf, key, keylen);
 74		memset(&ctx->buf[keylen], 0, BLAKE2S_BLOCK_SIZE - keylen);
 75		ctx->buflen = BLAKE2S_BLOCK_SIZE;
 76	}
 77}
 78
 79/**
 80 * blake2s_init() - Initialize a BLAKE2s context for a new message (unkeyed)
 81 * @ctx: the context to initialize
 82 * @outlen: length of output hash value in bytes, at most BLAKE2S_HASH_SIZE
 83 *
 84 * Context: Any context.
 85 */
 86static inline void blake2s_init(struct blake2s_ctx *ctx, size_t outlen)
 87{
 88	__blake2s_init(ctx, outlen, NULL, 0);
 89}
 90
 91/**
 92 * blake2s_init_key() - Initialize a BLAKE2s context for a new message (keyed)
 93 * @ctx: the context to initialize
 94 * @outlen: length of output hash value in bytes, at most BLAKE2S_HASH_SIZE
 95 * @key: the key
 96 * @keylen: the key length in bytes, at most BLAKE2S_KEY_SIZE
 97 *
 98 * Context: Any context.
 99 */
100static inline void blake2s_init_key(struct blake2s_ctx *ctx, size_t outlen,
101				    const void *key, size_t keylen)
102{
103	WARN_ON(IS_ENABLED(DEBUG) && (!outlen || outlen > BLAKE2S_HASH_SIZE ||
104		!key || !keylen || keylen > BLAKE2S_KEY_SIZE));
105
106	__blake2s_init(ctx, outlen, key, keylen);
107}
108
109/**
110 * blake2s_update() - Update a BLAKE2s context with message data
111 * @ctx: the context to update; must have been initialized
112 * @in: the message data
113 * @inlen: the data length in bytes
114 *
115 * This can be called any number of times.
116 *
117 * Context: Any context.
118 */
119void blake2s_update(struct blake2s_ctx *ctx, const u8 *in, size_t inlen);
120
121/**
122 * blake2s_final() - Finish computing a BLAKE2s hash
123 * @ctx: the context to finalize; must have been initialized
124 * @out: (output) the resulting BLAKE2s hash.  Its length will be equal to the
125 *	 @outlen that was passed to blake2s_init() or blake2s_init_key().
126 *
127 * After finishing, this zeroizes @ctx.  So the caller does not need to do it.
128 *
129 * Context: Any context.
130 */
131void blake2s_final(struct blake2s_ctx *ctx, u8 *out);
132
133/**
134 * blake2s() - Compute BLAKE2s hash in one shot
135 * @key: the key, or NULL for an unkeyed hash
136 * @keylen: the key length in bytes (at most BLAKE2S_KEY_SIZE), or 0 for an
137 *	    unkeyed hash
138 * @in: the message data
139 * @inlen: the data length in bytes
140 * @out: (output) the resulting BLAKE2s hash, with length @outlen
141 * @outlen: length of output hash value in bytes, at most BLAKE2S_HASH_SIZE
142 *
143 * Context: Any context.
144 */
145static inline void blake2s(const u8 *key, size_t keylen,
146			   const u8 *in, size_t inlen,
147			   u8 *out, size_t outlen)
148{
149	struct blake2s_ctx ctx;
150
151	WARN_ON(IS_ENABLED(DEBUG) && ((!in && inlen > 0) || !out || !outlen ||
152		outlen > BLAKE2S_HASH_SIZE || keylen > BLAKE2S_KEY_SIZE ||
153		(!key && keylen)));
154
155	__blake2s_init(&ctx, outlen, key, keylen);
156	blake2s_update(&ctx, in, inlen);
157	blake2s_final(&ctx, out);
158}
159
160#endif /* _CRYPTO_BLAKE2S_H */