1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Poly1305 authenticator algorithm, RFC7539
4 *
5 * Copyright (C) 2015 Martin Willi
6 *
7 * Based on public domain code by Andrew Moon and Daniel J. Bernstein.
8 */
9
10 #include <crypto/internal/blockhash.h>
11 #include <crypto/internal/poly1305.h>
12 #include <linux/export.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/string.h>
16 #include <linux/unaligned.h>
17
poly1305_init(struct poly1305_desc_ctx * desc,const u8 key[POLY1305_KEY_SIZE])18 void poly1305_init(struct poly1305_desc_ctx *desc,
19 const u8 key[POLY1305_KEY_SIZE])
20 {
21 desc->s[0] = get_unaligned_le32(key + 16);
22 desc->s[1] = get_unaligned_le32(key + 20);
23 desc->s[2] = get_unaligned_le32(key + 24);
24 desc->s[3] = get_unaligned_le32(key + 28);
25 desc->buflen = 0;
26 if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_POLY1305))
27 poly1305_block_init_arch(&desc->state, key);
28 else
29 poly1305_block_init_generic(&desc->state, key);
30 }
31 EXPORT_SYMBOL(poly1305_init);
32
poly1305_blocks(struct poly1305_block_state * state,const u8 * src,unsigned int len)33 static inline void poly1305_blocks(struct poly1305_block_state *state,
34 const u8 *src, unsigned int len)
35 {
36 if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_POLY1305))
37 poly1305_blocks_arch(state, src, len, 1);
38 else
39 poly1305_blocks_generic(state, src, len, 1);
40 }
41
poly1305_update(struct poly1305_desc_ctx * desc,const u8 * src,unsigned int nbytes)42 void poly1305_update(struct poly1305_desc_ctx *desc,
43 const u8 *src, unsigned int nbytes)
44 {
45 desc->buflen = BLOCK_HASH_UPDATE(poly1305_blocks, &desc->state,
46 src, nbytes, POLY1305_BLOCK_SIZE,
47 desc->buf, desc->buflen);
48 }
49 EXPORT_SYMBOL(poly1305_update);
50
poly1305_final(struct poly1305_desc_ctx * desc,u8 * dst)51 void poly1305_final(struct poly1305_desc_ctx *desc, u8 *dst)
52 {
53 if (unlikely(desc->buflen)) {
54 desc->buf[desc->buflen++] = 1;
55 memset(desc->buf + desc->buflen, 0,
56 POLY1305_BLOCK_SIZE - desc->buflen);
57 if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_POLY1305))
58 poly1305_blocks_arch(&desc->state, desc->buf,
59 POLY1305_BLOCK_SIZE, 0);
60 else
61 poly1305_blocks_generic(&desc->state, desc->buf,
62 POLY1305_BLOCK_SIZE, 0);
63 }
64
65 if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_POLY1305))
66 poly1305_emit_arch(&desc->state.h, dst, desc->s);
67 else
68 poly1305_emit_generic(&desc->state.h, dst, desc->s);
69 *desc = (struct poly1305_desc_ctx){};
70 }
71 EXPORT_SYMBOL(poly1305_final);
72
73 MODULE_LICENSE("GPL");
74 MODULE_AUTHOR("Martin Willi <martin@strongswan.org>");
75 MODULE_DESCRIPTION("Poly1305 authenticator algorithm, RFC7539");
76