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, const u8 *key);
62void poly1305_init_generic(struct poly1305_desc_ctx *desc, const u8 *key);
63
64static inline void poly1305_init(struct poly1305_desc_ctx *desc, const u8 *key)
65{
66	if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_POLY1305))
67		poly1305_init_arch(desc, key);
68	else
69		poly1305_init_generic(desc, key);
70}
71
72void poly1305_update_arch(struct poly1305_desc_ctx *desc, const u8 *src,
73			  unsigned int nbytes);
74void poly1305_update_generic(struct poly1305_desc_ctx *desc, const u8 *src,
75			     unsigned int nbytes);
76
77static inline void poly1305_update(struct poly1305_desc_ctx *desc,
78				   const u8 *src, unsigned int nbytes)
79{
80	if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_POLY1305))
81		poly1305_update_arch(desc, src, nbytes);
82	else
83		poly1305_update_generic(desc, src, nbytes);
84}
85
86void poly1305_final_arch(struct poly1305_desc_ctx *desc, u8 *digest);
87void poly1305_final_generic(struct poly1305_desc_ctx *desc, u8 *digest);
88
89static inline void poly1305_final(struct poly1305_desc_ctx *desc, u8 *digest)
90{
91	if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_POLY1305))
92		poly1305_final_arch(desc, digest);
93	else
94		poly1305_final_generic(desc, digest);
95}
96
97#endif