1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Common values for the Poly1305 algorithm
4 */
5
6#ifndef _CRYPTO_POLY1305_H
7#define _CRYPTO_POLY1305_H
8
9#include <linux/types.h>
10#include <linux/crypto.h>
11
12#define POLY1305_BLOCK_SIZE	16
13#define POLY1305_KEY_SIZE	32
14#define POLY1305_DIGEST_SIZE	16
15
16/* The poly1305_key and poly1305_state types are mostly opaque and
17 * implementation-defined. Limbs might be in base 2^64 or base 2^26, or
18 * different yet. The union type provided keeps these 64-bit aligned for the
19 * case in which this is implemented using 64x64 multiplies.
20 */
21
22struct poly1305_key {
23	union {
24		u32 r[5];
25		u64 r64[3];
26	};
27};
28
29struct poly1305_core_key {
30	struct poly1305_key key;
31	struct poly1305_key precomputed_s;
32};
33
34struct poly1305_state {
35	union {
36		u32 h[5];
37		u64 h64[3];
38	};
39};
40
41struct poly1305_desc_ctx {
42	/* partial buffer */
43	u8 buf[POLY1305_BLOCK_SIZE];
44	/* bytes used in partial buffer */
45	unsigned int buflen;
46	/* how many keys have been set in r[] */
47	unsigned short rset;
48	/* whether s[] has been set */
49	bool sset;
50	/* finalize key */
51	u32 s[4];
52	/* accumulator */
53	struct poly1305_state h;
54	/* key */
55	union {
56		struct poly1305_key opaque_r[CONFIG_CRYPTO_LIB_POLY1305_RSIZE];
57		struct poly1305_core_key core_r;
58	};
59};
60
61void poly1305_init_arch(struct poly1305_desc_ctx *desc,
62			const u8 key[POLY1305_KEY_SIZE]);
63void poly1305_init_generic(struct poly1305_desc_ctx *desc,
64			   const u8 key[POLY1305_KEY_SIZE]);
65
66static inline void poly1305_init(struct poly1305_desc_ctx *desc, const u8 *key)
67{
68	if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_POLY1305))
69		poly1305_init_arch(desc, key);
70	else
71		poly1305_init_generic(desc, key);
72}
73
74void poly1305_update_arch(struct poly1305_desc_ctx *desc, const u8 *src,
75			  unsigned int nbytes);
76void poly1305_update_generic(struct poly1305_desc_ctx *desc, const u8 *src,
77			     unsigned int nbytes);
78
79static inline void poly1305_update(struct poly1305_desc_ctx *desc,
80				   const u8 *src, unsigned int nbytes)
81{
82	if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_POLY1305))
83		poly1305_update_arch(desc, src, nbytes);
84	else
85		poly1305_update_generic(desc, src, nbytes);
86}
87
88void poly1305_final_arch(struct poly1305_desc_ctx *desc, u8 *digest);
89void poly1305_final_generic(struct poly1305_desc_ctx *desc, u8 *digest);
90
91static inline void poly1305_final(struct poly1305_desc_ctx *desc, u8 *digest)
92{
93	if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_POLY1305))
94		poly1305_final_arch(desc, digest);
95	else
96		poly1305_final_generic(desc, digest);
97}
98
99#endif
100