xref: /linux/lib/crypto/arm/poly1305.h (revision 7fc2cd2e4b398c57c9cf961cfea05eadbf34c05c)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * OpenSSL/Cryptogams accelerated Poly1305 transform for ARM
4  *
5  * Copyright (C) 2019 Linaro Ltd. <ard.biesheuvel@linaro.org>
6  */
7 
8 #include <asm/hwcap.h>
9 #include <asm/simd.h>
10 #include <linux/cpufeature.h>
11 #include <linux/jump_label.h>
12 #include <linux/kernel.h>
13 
14 asmlinkage void poly1305_block_init(struct poly1305_block_state *state,
15 				    const u8 raw_key[POLY1305_BLOCK_SIZE]);
16 asmlinkage void poly1305_blocks_arm(struct poly1305_block_state *state,
17 				    const u8 *src, u32 len, u32 hibit);
18 asmlinkage void poly1305_blocks_neon(struct poly1305_block_state *state,
19 				     const u8 *src, u32 len, u32 hibit);
20 asmlinkage void poly1305_emit(const struct poly1305_state *state,
21 			      u8 digest[POLY1305_DIGEST_SIZE],
22 			      const u32 nonce[4]);
23 
24 static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_neon);
25 
26 static void poly1305_blocks(struct poly1305_block_state *state, const u8 *src,
27 			    unsigned int len, u32 padbit)
28 {
29 	if (IS_ENABLED(CONFIG_KERNEL_MODE_NEON) &&
30 	    static_branch_likely(&have_neon) && likely(may_use_simd())) {
31 		do {
32 			unsigned int todo = min_t(unsigned int, len, SZ_4K);
33 
34 			scoped_ksimd()
35 				poly1305_blocks_neon(state, src, todo, padbit);
36 
37 			len -= todo;
38 			src += todo;
39 		} while (len);
40 	} else
41 		poly1305_blocks_arm(state, src, len, padbit);
42 }
43 
44 #ifdef CONFIG_KERNEL_MODE_NEON
45 #define poly1305_mod_init_arch poly1305_mod_init_arch
46 static void poly1305_mod_init_arch(void)
47 {
48 	if (elf_hwcap & HWCAP_NEON)
49 		static_branch_enable(&have_neon);
50 }
51 #endif /* CONFIG_KERNEL_MODE_NEON */
52