linux-stable/lib/crypto/poly1305-donna32.c
Arnd Bergmann 8d195e7a8a crypto: poly1305 - fix poly1305_core_setkey() declaration
gcc-11 points out a mismatch between the declaration and the definition
of poly1305_core_setkey():

lib/crypto/poly1305-donna32.c:13:67: error: argument 2 of type ‘const u8[16]’ {aka ‘const unsigned char[16]’} with mismatched bound [-Werror=array-parameter=]
   13 | void poly1305_core_setkey(struct poly1305_core_key *key, const u8 raw_key[16])
      |                                                          ~~~~~~~~~^~~~~~~~~~~
In file included from lib/crypto/poly1305-donna32.c:11:
include/crypto/internal/poly1305.h:21:68: note: previously declared as ‘const u8 *’ {aka ‘const unsigned char *’}
   21 | void poly1305_core_setkey(struct poly1305_core_key *key, const u8 *raw_key);

This is harmless in principle, as the calling conventions are the same,
but the more specific prototype allows better type checking in the
caller.

Change the declaration to match the actual function definition.
The poly1305_simd_init() is a bit suspicious here, as it previously
had a 32-byte argument type, but looks like it needs to take the
16-byte POLY1305_BLOCK_SIZE array instead.

Fixes: 1c08a10436 ("crypto: poly1305 - add new 32 and 64-bit generic versions")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2021-04-02 18:28:12 +11:00

205 lines
4.7 KiB
C

// SPDX-License-Identifier: GPL-2.0 OR MIT
/*
* Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
*
* This is based in part on Andrew Moon's poly1305-donna, which is in the
* public domain.
*/
#include <linux/kernel.h>
#include <asm/unaligned.h>
#include <crypto/internal/poly1305.h>
void poly1305_core_setkey(struct poly1305_core_key *key,
const u8 raw_key[POLY1305_BLOCK_SIZE])
{
/* r &= 0xffffffc0ffffffc0ffffffc0fffffff */
key->key.r[0] = (get_unaligned_le32(&raw_key[0])) & 0x3ffffff;
key->key.r[1] = (get_unaligned_le32(&raw_key[3]) >> 2) & 0x3ffff03;
key->key.r[2] = (get_unaligned_le32(&raw_key[6]) >> 4) & 0x3ffc0ff;
key->key.r[3] = (get_unaligned_le32(&raw_key[9]) >> 6) & 0x3f03fff;
key->key.r[4] = (get_unaligned_le32(&raw_key[12]) >> 8) & 0x00fffff;
/* s = 5*r */
key->precomputed_s.r[0] = key->key.r[1] * 5;
key->precomputed_s.r[1] = key->key.r[2] * 5;
key->precomputed_s.r[2] = key->key.r[3] * 5;
key->precomputed_s.r[3] = key->key.r[4] * 5;
}
EXPORT_SYMBOL(poly1305_core_setkey);
void poly1305_core_blocks(struct poly1305_state *state,
const struct poly1305_core_key *key, const void *src,
unsigned int nblocks, u32 hibit)
{
const u8 *input = src;
u32 r0, r1, r2, r3, r4;
u32 s1, s2, s3, s4;
u32 h0, h1, h2, h3, h4;
u64 d0, d1, d2, d3, d4;
u32 c;
if (!nblocks)
return;
hibit <<= 24;
r0 = key->key.r[0];
r1 = key->key.r[1];
r2 = key->key.r[2];
r3 = key->key.r[3];
r4 = key->key.r[4];
s1 = key->precomputed_s.r[0];
s2 = key->precomputed_s.r[1];
s3 = key->precomputed_s.r[2];
s4 = key->precomputed_s.r[3];
h0 = state->h[0];
h1 = state->h[1];
h2 = state->h[2];
h3 = state->h[3];
h4 = state->h[4];
do {
/* h += m[i] */
h0 += (get_unaligned_le32(&input[0])) & 0x3ffffff;
h1 += (get_unaligned_le32(&input[3]) >> 2) & 0x3ffffff;
h2 += (get_unaligned_le32(&input[6]) >> 4) & 0x3ffffff;
h3 += (get_unaligned_le32(&input[9]) >> 6) & 0x3ffffff;
h4 += (get_unaligned_le32(&input[12]) >> 8) | hibit;
/* h *= r */
d0 = ((u64)h0 * r0) + ((u64)h1 * s4) +
((u64)h2 * s3) + ((u64)h3 * s2) +
((u64)h4 * s1);
d1 = ((u64)h0 * r1) + ((u64)h1 * r0) +
((u64)h2 * s4) + ((u64)h3 * s3) +
((u64)h4 * s2);
d2 = ((u64)h0 * r2) + ((u64)h1 * r1) +
((u64)h2 * r0) + ((u64)h3 * s4) +
((u64)h4 * s3);
d3 = ((u64)h0 * r3) + ((u64)h1 * r2) +
((u64)h2 * r1) + ((u64)h3 * r0) +
((u64)h4 * s4);
d4 = ((u64)h0 * r4) + ((u64)h1 * r3) +
((u64)h2 * r2) + ((u64)h3 * r1) +
((u64)h4 * r0);
/* (partial) h %= p */
c = (u32)(d0 >> 26);
h0 = (u32)d0 & 0x3ffffff;
d1 += c;
c = (u32)(d1 >> 26);
h1 = (u32)d1 & 0x3ffffff;
d2 += c;
c = (u32)(d2 >> 26);
h2 = (u32)d2 & 0x3ffffff;
d3 += c;
c = (u32)(d3 >> 26);
h3 = (u32)d3 & 0x3ffffff;
d4 += c;
c = (u32)(d4 >> 26);
h4 = (u32)d4 & 0x3ffffff;
h0 += c * 5;
c = (h0 >> 26);
h0 = h0 & 0x3ffffff;
h1 += c;
input += POLY1305_BLOCK_SIZE;
} while (--nblocks);
state->h[0] = h0;
state->h[1] = h1;
state->h[2] = h2;
state->h[3] = h3;
state->h[4] = h4;
}
EXPORT_SYMBOL(poly1305_core_blocks);
void poly1305_core_emit(const struct poly1305_state *state, const u32 nonce[4],
void *dst)
{
u8 *mac = dst;
u32 h0, h1, h2, h3, h4, c;
u32 g0, g1, g2, g3, g4;
u64 f;
u32 mask;
/* fully carry h */
h0 = state->h[0];
h1 = state->h[1];
h2 = state->h[2];
h3 = state->h[3];
h4 = state->h[4];
c = h1 >> 26;
h1 = h1 & 0x3ffffff;
h2 += c;
c = h2 >> 26;
h2 = h2 & 0x3ffffff;
h3 += c;
c = h3 >> 26;
h3 = h3 & 0x3ffffff;
h4 += c;
c = h4 >> 26;
h4 = h4 & 0x3ffffff;
h0 += c * 5;
c = h0 >> 26;
h0 = h0 & 0x3ffffff;
h1 += c;
/* compute h + -p */
g0 = h0 + 5;
c = g0 >> 26;
g0 &= 0x3ffffff;
g1 = h1 + c;
c = g1 >> 26;
g1 &= 0x3ffffff;
g2 = h2 + c;
c = g2 >> 26;
g2 &= 0x3ffffff;
g3 = h3 + c;
c = g3 >> 26;
g3 &= 0x3ffffff;
g4 = h4 + c - (1UL << 26);
/* select h if h < p, or h + -p if h >= p */
mask = (g4 >> ((sizeof(u32) * 8) - 1)) - 1;
g0 &= mask;
g1 &= mask;
g2 &= mask;
g3 &= mask;
g4 &= mask;
mask = ~mask;
h0 = (h0 & mask) | g0;
h1 = (h1 & mask) | g1;
h2 = (h2 & mask) | g2;
h3 = (h3 & mask) | g3;
h4 = (h4 & mask) | g4;
/* h = h % (2^128) */
h0 = ((h0) | (h1 << 26)) & 0xffffffff;
h1 = ((h1 >> 6) | (h2 << 20)) & 0xffffffff;
h2 = ((h2 >> 12) | (h3 << 14)) & 0xffffffff;
h3 = ((h3 >> 18) | (h4 << 8)) & 0xffffffff;
if (likely(nonce)) {
/* mac = (h + nonce) % (2^128) */
f = (u64)h0 + nonce[0];
h0 = (u32)f;
f = (u64)h1 + nonce[1] + (f >> 32);
h1 = (u32)f;
f = (u64)h2 + nonce[2] + (f >> 32);
h2 = (u32)f;
f = (u64)h3 + nonce[3] + (f >> 32);
h3 = (u32)f;
}
put_unaligned_le32(h0, &mac[0]);
put_unaligned_le32(h1, &mac[4]);
put_unaligned_le32(h2, &mac[8]);
put_unaligned_le32(h3, &mac[12]);
}
EXPORT_SYMBOL(poly1305_core_emit);