xref: /linux/include/crypto/blake2b.h (revision ba6617bd47c2263bd2ead34e1b31d90c66af5dea)
1 /* SPDX-License-Identifier: GPL-2.0 OR MIT */
2 
3 #ifndef _CRYPTO_BLAKE2B_H
4 #define _CRYPTO_BLAKE2B_H
5 
6 #include <linux/bug.h>
7 #include <linux/types.h>
8 #include <linux/string.h>
9 
10 struct blake2b_state {
11 	/* 'h', 't', and 'f' are used in assembly code, so keep them as-is. */
12 	u64 h[8];
13 	u64 t[2];
14 	/* The true state ends here.  The rest is temporary storage. */
15 	u64 f[2];
16 };
17 
18 enum blake2b_lengths {
19 	BLAKE2B_BLOCK_SIZE = 128,
20 	BLAKE2B_HASH_SIZE = 64,
21 	BLAKE2B_KEY_SIZE = 64,
22 	BLAKE2B_STATE_SIZE = offsetof(struct blake2b_state, f),
23 	BLAKE2B_DESC_SIZE = sizeof(struct blake2b_state),
24 
25 	BLAKE2B_160_HASH_SIZE = 20,
26 	BLAKE2B_256_HASH_SIZE = 32,
27 	BLAKE2B_384_HASH_SIZE = 48,
28 	BLAKE2B_512_HASH_SIZE = 64,
29 };
30 
31 /**
32  * struct blake2b_ctx - Context for hashing a message with BLAKE2b
33  * @h: compression function state
34  * @t: block counter
35  * @f: finalization indicator
36  * @buf: partial block buffer; 'buflen' bytes are valid
37  * @buflen: number of bytes buffered in @buf
38  * @outlen: length of output hash value in bytes, at most BLAKE2B_HASH_SIZE
39  */
40 struct blake2b_ctx {
41 	/* 'h', 't', and 'f' are used in assembly code, so keep them as-is. */
42 	u64 h[8];
43 	u64 t[2];
44 	u64 f[2];
45 	u8 buf[BLAKE2B_BLOCK_SIZE];
46 	unsigned int buflen;
47 	unsigned int outlen;
48 };
49 
50 enum blake2b_iv {
51 	BLAKE2B_IV0 = 0x6A09E667F3BCC908ULL,
52 	BLAKE2B_IV1 = 0xBB67AE8584CAA73BULL,
53 	BLAKE2B_IV2 = 0x3C6EF372FE94F82BULL,
54 	BLAKE2B_IV3 = 0xA54FF53A5F1D36F1ULL,
55 	BLAKE2B_IV4 = 0x510E527FADE682D1ULL,
56 	BLAKE2B_IV5 = 0x9B05688C2B3E6C1FULL,
57 	BLAKE2B_IV6 = 0x1F83D9ABFB41BD6BULL,
58 	BLAKE2B_IV7 = 0x5BE0CD19137E2179ULL,
59 };
60 
61 static inline void __blake2b_init(struct blake2b_ctx *ctx, size_t outlen,
62 				  const void *key, size_t keylen)
63 {
64 	ctx->h[0] = BLAKE2B_IV0 ^ (0x01010000 | keylen << 8 | outlen);
65 	ctx->h[1] = BLAKE2B_IV1;
66 	ctx->h[2] = BLAKE2B_IV2;
67 	ctx->h[3] = BLAKE2B_IV3;
68 	ctx->h[4] = BLAKE2B_IV4;
69 	ctx->h[5] = BLAKE2B_IV5;
70 	ctx->h[6] = BLAKE2B_IV6;
71 	ctx->h[7] = BLAKE2B_IV7;
72 	ctx->t[0] = 0;
73 	ctx->t[1] = 0;
74 	ctx->f[0] = 0;
75 	ctx->f[1] = 0;
76 	ctx->buflen = 0;
77 	ctx->outlen = outlen;
78 	if (keylen) {
79 		memcpy(ctx->buf, key, keylen);
80 		memset(&ctx->buf[keylen], 0, BLAKE2B_BLOCK_SIZE - keylen);
81 		ctx->buflen = BLAKE2B_BLOCK_SIZE;
82 	}
83 }
84 
85 /**
86  * blake2b_init() - Initialize a BLAKE2b context for a new message (unkeyed)
87  * @ctx: the context to initialize
88  * @outlen: length of output hash value in bytes, at most BLAKE2B_HASH_SIZE
89  *
90  * Context: Any context.
91  */
92 static inline void blake2b_init(struct blake2b_ctx *ctx, size_t outlen)
93 {
94 	__blake2b_init(ctx, outlen, NULL, 0);
95 }
96 
97 /**
98  * blake2b_init_key() - Initialize a BLAKE2b context for a new message (keyed)
99  * @ctx: the context to initialize
100  * @outlen: length of output hash value in bytes, at most BLAKE2B_HASH_SIZE
101  * @key: the key
102  * @keylen: the key length in bytes, at most BLAKE2B_KEY_SIZE
103  *
104  * Context: Any context.
105  */
106 static inline void blake2b_init_key(struct blake2b_ctx *ctx, size_t outlen,
107 				    const void *key, size_t keylen)
108 {
109 	WARN_ON(IS_ENABLED(DEBUG) && (!outlen || outlen > BLAKE2B_HASH_SIZE ||
110 		!key || !keylen || keylen > BLAKE2B_KEY_SIZE));
111 
112 	__blake2b_init(ctx, outlen, key, keylen);
113 }
114 
115 /**
116  * blake2b_update() - Update a BLAKE2b context with message data
117  * @ctx: the context to update; must have been initialized
118  * @in: the message data
119  * @inlen: the data length in bytes
120  *
121  * This can be called any number of times.
122  *
123  * Context: Any context.
124  */
125 void blake2b_update(struct blake2b_ctx *ctx, const u8 *in, size_t inlen);
126 
127 /**
128  * blake2b_final() - Finish computing a BLAKE2b hash
129  * @ctx: the context to finalize; must have been initialized
130  * @out: (output) the resulting BLAKE2b hash.  Its length will be equal to the
131  *	 @outlen that was passed to blake2b_init() or blake2b_init_key().
132  *
133  * After finishing, this zeroizes @ctx.  So the caller does not need to do it.
134  *
135  * Context: Any context.
136  */
137 void blake2b_final(struct blake2b_ctx *ctx, u8 *out);
138 
139 /**
140  * blake2b() - Compute BLAKE2b hash in one shot
141  * @key: the key, or NULL for an unkeyed hash
142  * @keylen: the key length in bytes (at most BLAKE2B_KEY_SIZE), or 0 for an
143  *	    unkeyed hash
144  * @in: the message data
145  * @inlen: the data length in bytes
146  * @out: (output) the resulting BLAKE2b hash, with length @outlen
147  * @outlen: length of output hash value in bytes, at most BLAKE2B_HASH_SIZE
148  *
149  * Context: Any context.
150  */
151 static inline void blake2b(const u8 *key, size_t keylen,
152 			   const u8 *in, size_t inlen,
153 			   u8 *out, size_t outlen)
154 {
155 	struct blake2b_ctx ctx;
156 
157 	WARN_ON(IS_ENABLED(DEBUG) && ((!in && inlen > 0) || !out || !outlen ||
158 		outlen > BLAKE2B_HASH_SIZE || keylen > BLAKE2B_KEY_SIZE ||
159 		(!key && keylen)));
160 
161 	__blake2b_init(&ctx, outlen, key, keylen);
162 	blake2b_update(&ctx, in, inlen);
163 	blake2b_final(&ctx, out);
164 }
165 
166 #endif /* _CRYPTO_BLAKE2B_H */
167