diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/crypto/Kconfig | 3 | ||||
| -rw-r--r-- | lib/crypto/Makefile | 3 | ||||
| -rw-r--r-- | lib/crypto/poly1305.c | 158 |
3 files changed, 164 insertions, 0 deletions
diff --git a/lib/crypto/Kconfig b/lib/crypto/Kconfig index 6a11931ae105..c4882d29879e 100644 --- a/lib/crypto/Kconfig +++ b/lib/crypto/Kconfig @@ -37,5 +37,8 @@ config CRYPTO_LIB_CHACHA config CRYPTO_LIB_DES tristate +config CRYPTO_LIB_POLY1305_GENERIC + tristate + config CRYPTO_LIB_SHA256 tristate diff --git a/lib/crypto/Makefile b/lib/crypto/Makefile index 0ce40604e104..b58ab6843a9d 100644 --- a/lib/crypto/Makefile +++ b/lib/crypto/Makefile @@ -13,5 +13,8 @@ libarc4-y := arc4.o obj-$(CONFIG_CRYPTO_LIB_DES) += libdes.o libdes-y := des.o +obj-$(CONFIG_CRYPTO_LIB_POLY1305_GENERIC) += libpoly1305.o +libpoly1305-y := poly1305.o + obj-$(CONFIG_CRYPTO_LIB_SHA256) += libsha256.o libsha256-y := sha256.o diff --git a/lib/crypto/poly1305.c b/lib/crypto/poly1305.c new file mode 100644 index 000000000000..f019a57dbc1b --- /dev/null +++ b/lib/crypto/poly1305.c @@ -0,0 +1,158 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Poly1305 authenticator algorithm, RFC7539 + * + * Copyright (C) 2015 Martin Willi + * + * Based on public domain code by Andrew Moon and Daniel J. Bernstein. + */ + +#include <crypto/internal/poly1305.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <asm/unaligned.h> + +static inline u64 mlt(u64 a, u64 b) +{ + return a * b; +} + +static inline u32 sr(u64 v, u_char n) +{ + return v >> n; +} + +static inline u32 and(u32 v, u32 mask) +{ + return v & mask; +} + +void poly1305_core_setkey(struct poly1305_key *key, const u8 *raw_key) +{ + /* r &= 0xffffffc0ffffffc0ffffffc0fffffff */ + key->r[0] = (get_unaligned_le32(raw_key + 0) >> 0) & 0x3ffffff; + key->r[1] = (get_unaligned_le32(raw_key + 3) >> 2) & 0x3ffff03; + key->r[2] = (get_unaligned_le32(raw_key + 6) >> 4) & 0x3ffc0ff; + key->r[3] = (get_unaligned_le32(raw_key + 9) >> 6) & 0x3f03fff; + key->r[4] = (get_unaligned_le32(raw_key + 12) >> 8) & 0x00fffff; +} +EXPORT_SYMBOL_GPL(poly1305_core_setkey); + +void poly1305_core_blocks(struct poly1305_state *state, + const struct poly1305_key *key, const void *src, + unsigned int nblocks, u32 hibit) +{ + u32 r0, r1, r2, r3, r4; + u32 s1, s2, s3, s4; + u32 h0, h1, h2, h3, h4; + u64 d0, d1, d2, d3, d4; + + if (!nblocks) + return; + + r0 = key->r[0]; + r1 = key->r[1]; + r2 = key->r[2]; + r3 = key->r[3]; + r4 = key->r[4]; + + s1 = r1 * 5; + s2 = r2 * 5; + s3 = r3 * 5; + s4 = r4 * 5; + + 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(src + 0) >> 0) & 0x3ffffff; + h1 += (get_unaligned_le32(src + 3) >> 2) & 0x3ffffff; + h2 += (get_unaligned_le32(src + 6) >> 4) & 0x3ffffff; + h3 += (get_unaligned_le32(src + 9) >> 6) & 0x3ffffff; + h4 += (get_unaligned_le32(src + 12) >> 8) | (hibit << 24); + + /* h *= r */ + d0 = mlt(h0, r0) + mlt(h1, s4) + mlt(h2, s3) + + mlt(h3, s2) + mlt(h4, s1); + d1 = mlt(h0, r1) + mlt(h1, r0) + mlt(h2, s4) + + mlt(h3, s3) + mlt(h4, s2); + d2 = mlt(h0, r2) + mlt(h1, r1) + mlt(h2, r0) + + mlt(h3, s4) + mlt(h4, s3); + d3 = mlt(h0, r3) + mlt(h1, r2) + mlt(h2, r1) + + mlt(h3, r0) + mlt(h4, s4); + d4 = mlt(h0, r4) + mlt(h1, r3) + mlt(h2, r2) + + mlt(h3, r1) + mlt(h4, r0); + + /* (partial) h %= p */ + d1 += sr(d0, 26); h0 = and(d0, 0x3ffffff); + d2 += sr(d1, 26); h1 = and(d1, 0x3ffffff); + d3 += sr(d2, 26); h2 = and(d2, 0x3ffffff); + d4 += sr(d3, 26); h3 = and(d3, 0x3ffffff); + h0 += sr(d4, 26) * 5; h4 = and(d4, 0x3ffffff); + h1 += h0 >> 26; h0 = h0 & 0x3ffffff; + + src += 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_GPL(poly1305_core_blocks); + +void poly1305_core_emit(const struct poly1305_state *state, void *dst) +{ + u32 h0, h1, h2, h3, h4; + u32 g0, g1, g2, g3, g4; + 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]; + + h2 += (h1 >> 26); h1 = h1 & 0x3ffffff; + h3 += (h2 >> 26); h2 = h2 & 0x3ffffff; + h4 += (h3 >> 26); h3 = h3 & 0x3ffffff; + h0 += (h4 >> 26) * 5; h4 = h4 & 0x3ffffff; + h1 += (h0 >> 26); h0 = h0 & 0x3ffffff; + + /* compute h + -p */ + g0 = h0 + 5; + g1 = h1 + (g0 >> 26); g0 &= 0x3ffffff; + g2 = h2 + (g1 >> 26); g1 &= 0x3ffffff; + g3 = h3 + (g2 >> 26); g2 &= 0x3ffffff; + g4 = h4 + (g3 >> 26) - (1 << 26); g3 &= 0x3ffffff; + + /* 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) */ + put_unaligned_le32((h0 >> 0) | (h1 << 26), dst + 0); + put_unaligned_le32((h1 >> 6) | (h2 << 20), dst + 4); + put_unaligned_le32((h2 >> 12) | (h3 << 14), dst + 8); + put_unaligned_le32((h3 >> 18) | (h4 << 8), dst + 12); +} +EXPORT_SYMBOL_GPL(poly1305_core_emit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Martin Willi <martin@strongswan.org>"); |