Message ID | 79e47ab2c559c974d950a238e9db909795b4268d.1571934170.git.dsterba@suse.com (mailing list archive) |
---|---|
State | Accepted |
Delegated to: | Herbert Xu |
Headers | show |
Series | BLAKE2b generic implementation | expand |
On Thu, Oct 24, 2019 at 06:28:31PM +0200, David Sterba wrote: > The patch brings support of several BLAKE2 variants (2b with various > digest lengths). The keyed digest is supported, using tfm->setkey call. > The in-tree user will be btrfs (for checksumming), we're going to use > the BLAKE2b-256 variant. > > The code is reference implementation taken from the official sources and > modified in terms of kernel coding style (whitespace, comments, uintXX_t > -> uXX types, removed unused prototypes and #ifdefs, removed testing > code, changed secure_zero_memory -> memzero_explicit, used own helpers > for unaligned reads/writes and rotations). > > Further changes removed sanity checks of key length or output size, > these values are verified in the crypto API callbacks or hardcoded in > shash_alg and not exposed to users. > > Signed-off-by: David Sterba <dsterba@suse.com> > --- > crypto/Kconfig | 17 ++ > crypto/Makefile | 1 + > crypto/blake2b_generic.c | 435 +++++++++++++++++++++++++++++++++++++++ > 3 files changed, 453 insertions(+) > create mode 100644 crypto/blake2b_generic.c > This looks good enough now, though it would be nice to clean up some more of the cruft that isn't actually needed and add a few of the optimizations from the BLAKE2s code that is being proposed. E.g. we could easily save 120 lines with the following: diff --git a/crypto/blake2b_generic.c b/crypto/blake2b_generic.c index 8dab65612a41..22179ae3c7b7 100644 --- a/crypto/blake2b_generic.c +++ b/crypto/blake2b_generic.c @@ -32,10 +32,7 @@ enum blake2b_constant { BLAKE2B_BLOCKBYTES = 128, - BLAKE2B_OUTBYTES = 64, BLAKE2B_KEYBYTES = 64, - BLAKE2B_SALTBYTES = 16, - BLAKE2B_PERSONALBYTES = 16 }; struct blake2b_state { @@ -44,25 +41,8 @@ struct blake2b_state { u64 f[2]; u8 buf[BLAKE2B_BLOCKBYTES]; size_t buflen; - size_t outlen; - u8 last_node; }; -struct blake2b_param { - u8 digest_length; /* 1 */ - u8 key_length; /* 2 */ - u8 fanout; /* 3 */ - u8 depth; /* 4 */ - __le32 leaf_length; /* 8 */ - __le32 node_offset; /* 12 */ - __le32 xof_length; /* 16 */ - u8 node_depth; /* 17 */ - u8 inner_length; /* 18 */ - u8 reserved[14]; /* 32 */ - u8 salt[BLAKE2B_SALTBYTES]; /* 48 */ - u8 personal[BLAKE2B_PERSONALBYTES]; /* 64 */ -} __packed; - static const u64 blake2b_IV[8] = { 0x6a09e667f3bcc908ULL, 0xbb67ae8584caa73bULL, 0x3c6ef372fe94f82bULL, 0xa54ff53a5f1d36f1ULL, @@ -85,18 +65,8 @@ static const u8 blake2b_sigma[12][16] = { { 14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3 } }; -static void blake2b_update(struct blake2b_state *S, const void *pin, size_t inlen); - -static void blake2b_set_lastnode(struct blake2b_state *S) -{ - S->f[1] = (u64)-1; -} - static void blake2b_set_lastblock(struct blake2b_state *S) { - if (S->last_node) - blake2b_set_lastnode(S); - S->f[0] = (u64)-1; } @@ -106,81 +76,6 @@ static void blake2b_increment_counter(struct blake2b_state *S, const u64 inc) S->t[1] += (S->t[0] < inc); } -static void blake2b_init0(struct blake2b_state *S) -{ - size_t i; - - memset(S, 0, sizeof(struct blake2b_state)); - - for (i = 0; i < 8; ++i) - S->h[i] = blake2b_IV[i]; -} - -/* init xors IV with input parameter block */ -static void blake2b_init_param(struct blake2b_state *S, - const struct blake2b_param *P) -{ - const u8 *p = (const u8 *)(P); - size_t i; - - blake2b_init0(S); - - /* IV XOR ParamBlock */ - for (i = 0; i < 8; ++i) - S->h[i] ^= get_unaligned_le64(p + sizeof(S->h[i]) * i); - - S->outlen = P->digest_length; -} - -static void blake2b_init(struct blake2b_state *S, size_t outlen) -{ - struct blake2b_param P; - - P.digest_length = (u8)outlen; - P.key_length = 0; - P.fanout = 1; - P.depth = 1; - P.leaf_length = 0; - P.node_offset = 0; - P.xof_length = 0; - P.node_depth = 0; - P.inner_length = 0; - memset(P.reserved, 0, sizeof(P.reserved)); - memset(P.salt, 0, sizeof(P.salt)); - memset(P.personal, 0, sizeof(P.personal)); - blake2b_init_param(S, &P); -} - -static void blake2b_init_key(struct blake2b_state *S, size_t outlen, - const void *key, size_t keylen) -{ - struct blake2b_param P; - - P.digest_length = (u8)outlen; - P.key_length = (u8)keylen; - P.fanout = 1; - P.depth = 1; - P.leaf_length = 0; - P.node_offset = 0; - P.xof_length = 0; - P.node_depth = 0; - P.inner_length = 0; - memset(P.reserved, 0, sizeof(P.reserved)); - memset(P.salt, 0, sizeof(P.salt)); - memset(P.personal, 0, sizeof(P.personal)); - - blake2b_init_param(S, &P); - - { - u8 block[BLAKE2B_BLOCKBYTES]; - - memset(block, 0, BLAKE2B_BLOCKBYTES); - memcpy(block, key, keylen); - blake2b_update(S, block, BLAKE2B_BLOCKBYTES); - memzero_explicit(block, BLAKE2B_BLOCKBYTES); - } -} - #define G(r,i,a,b,c,d) \ do { \ a = a + b + m[blake2b_sigma[r][2*i+0]]; \ @@ -247,103 +142,86 @@ static void blake2b_compress(struct blake2b_state *S, #undef G #undef ROUND -static void blake2b_update(struct blake2b_state *S, const void *pin, size_t inlen) -{ - const u8 *in = (const u8 *)pin; - - if (inlen > 0) { - size_t left = S->buflen; - size_t fill = BLAKE2B_BLOCKBYTES - left; - - if (inlen > fill) { - S->buflen = 0; - /* Fill buffer */ - memcpy(S->buf + left, in, fill); - blake2b_increment_counter(S, BLAKE2B_BLOCKBYTES); - /* Compress */ - blake2b_compress(S, S->buf); - in += fill; - inlen -= fill; - while (inlen > BLAKE2B_BLOCKBYTES) { - blake2b_increment_counter(S, BLAKE2B_BLOCKBYTES); - blake2b_compress(S, in); - in += BLAKE2B_BLOCKBYTES; - inlen -= BLAKE2B_BLOCKBYTES; - } - } - memcpy(S->buf + S->buflen, in, inlen); - S->buflen += inlen; - } -} - -static void blake2b_final(struct blake2b_state *S, void *out, size_t outlen) -{ - u8 buffer[BLAKE2B_OUTBYTES] = {0}; - size_t i; - - blake2b_increment_counter(S, S->buflen); - blake2b_set_lastblock(S); - /* Padding */ - memset(S->buf + S->buflen, 0, BLAKE2B_BLOCKBYTES - S->buflen); - blake2b_compress(S, S->buf); - - /* Output full hash to temp buffer */ - for (i = 0; i < 8; ++i) - put_unaligned_le64(S->h[i], buffer + sizeof(S->h[i]) * i); - - memcpy(out, buffer, S->outlen); - memzero_explicit(buffer, sizeof(buffer)); -} - -struct digest_tfm_ctx { +struct blake2b_tfm_ctx { u8 key[BLAKE2B_KEYBYTES]; unsigned int keylen; }; -static int digest_setkey(struct crypto_shash *tfm, const u8 *key, - unsigned int keylen) +static int blake2b_setkey(struct crypto_shash *tfm, const u8 *key, + unsigned int keylen) { - struct digest_tfm_ctx *mctx = crypto_shash_ctx(tfm); + struct blake2b_tfm_ctx *tctx = crypto_shash_ctx(tfm); if (keylen == 0 || keylen > BLAKE2B_KEYBYTES) { crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); return -EINVAL; } - memcpy(mctx->key, key, keylen); - mctx->keylen = keylen; - + memcpy(tctx->key, key, keylen); + tctx->keylen = keylen; return 0; } -static int digest_init(struct shash_desc *desc) +static int blake2b_init(struct shash_desc *desc) { - struct digest_tfm_ctx *mctx = crypto_shash_ctx(desc->tfm); - struct blake2b_state *state = shash_desc_ctx(desc); - const int digestsize = crypto_shash_digestsize(desc->tfm); - - if (mctx->keylen == 0) - blake2b_init(state, digestsize); - else - blake2b_init_key(state, digestsize, mctx->key, mctx->keylen); + struct blake2b_state *S = shash_desc_ctx(desc); + const struct blake2b_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm); + const unsigned int outlen = crypto_shash_digestsize(desc->tfm); + + memset(S, 0, sizeof(*S)); + memcpy(S->h, blake2b_IV, sizeof(S->h)); + S->h[0] ^= 0x01010000 | tctx->keylen << 8 | outlen; + if (tctx->keylen) { + memcpy(S->buf, tctx->key, tctx->keylen); + S->buflen = BLAKE2B_BLOCKBYTES; + } return 0; } -static int digest_update(struct shash_desc *desc, const u8 *data, - unsigned int length) +static int blake2b_update(struct shash_desc *desc, const u8 *in, + unsigned int inlen) { - struct blake2b_state *state = shash_desc_ctx(desc); - - blake2b_update(state, data, length); + struct blake2b_state *S = shash_desc_ctx(desc); + size_t left = S->buflen; + size_t fill = BLAKE2B_BLOCKBYTES - left; + + if (!inlen) + return 0; + if (inlen > fill) { + S->buflen = 0; + /* Fill buffer */ + memcpy(S->buf + left, in, fill); + blake2b_increment_counter(S, BLAKE2B_BLOCKBYTES); + /* Compress */ + blake2b_compress(S, S->buf); + in += fill; + inlen -= fill; + while (inlen > BLAKE2B_BLOCKBYTES) { + blake2b_increment_counter(S, BLAKE2B_BLOCKBYTES); + blake2b_compress(S, in); + in += BLAKE2B_BLOCKBYTES; + inlen -= BLAKE2B_BLOCKBYTES; + } + } + memcpy(S->buf + S->buflen, in, inlen); + S->buflen += inlen; return 0; } -static int digest_final(struct shash_desc *desc, u8 *out) +static int blake2b_final(struct shash_desc *desc, u8 *out) { - struct blake2b_state *state = shash_desc_ctx(desc); - const int digestsize = crypto_shash_digestsize(desc->tfm); + struct blake2b_state *S = shash_desc_ctx(desc); + const unsigned int outlen = crypto_shash_digestsize(desc->tfm); + size_t i; - blake2b_final(state, out, digestsize); + blake2b_increment_counter(S, S->buflen); + blake2b_set_lastblock(S); + /* Padding */ + memset(S->buf + S->buflen, 0, BLAKE2B_BLOCKBYTES - S->buflen); + blake2b_compress(S, S->buf); + for (i = 0; i < 8; ++i) + __cpu_to_le64s(&S->h[i]); + memcpy(out, S->h, outlen); return 0; } @@ -354,13 +232,13 @@ static struct shash_alg blake2b_algs[] = { .base.cra_priority = 100, .base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY, .base.cra_blocksize = BLAKE2B_BLOCKBYTES, - .base.cra_ctxsize = sizeof(struct digest_tfm_ctx), + .base.cra_ctxsize = sizeof(struct blake2b_tfm_ctx), .base.cra_module = THIS_MODULE, .digestsize = BLAKE2B_160_DIGEST_SIZE, - .setkey = digest_setkey, - .init = digest_init, - .update = digest_update, - .final = digest_final, + .setkey = blake2b_setkey, + .init = blake2b_init, + .update = blake2b_update, + .final = blake2b_final, .descsize = sizeof(struct blake2b_state), }, { .base.cra_name = "blake2b-256", @@ -368,13 +246,13 @@ static struct shash_alg blake2b_algs[] = { .base.cra_priority = 100, .base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY, .base.cra_blocksize = BLAKE2B_BLOCKBYTES, - .base.cra_ctxsize = sizeof(struct digest_tfm_ctx), + .base.cra_ctxsize = sizeof(struct blake2b_tfm_ctx), .base.cra_module = THIS_MODULE, .digestsize = BLAKE2B_256_DIGEST_SIZE, - .setkey = digest_setkey, - .init = digest_init, - .update = digest_update, - .final = digest_final, + .setkey = blake2b_setkey, + .init = blake2b_init, + .update = blake2b_update, + .final = blake2b_final, .descsize = sizeof(struct blake2b_state), }, { .base.cra_name = "blake2b-384", @@ -382,13 +260,13 @@ static struct shash_alg blake2b_algs[] = { .base.cra_priority = 100, .base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY, .base.cra_blocksize = BLAKE2B_BLOCKBYTES, - .base.cra_ctxsize = sizeof(struct digest_tfm_ctx), + .base.cra_ctxsize = sizeof(struct blake2b_tfm_ctx), .base.cra_module = THIS_MODULE, .digestsize = BLAKE2B_384_DIGEST_SIZE, - .setkey = digest_setkey, - .init = digest_init, - .update = digest_update, - .final = digest_final, + .setkey = blake2b_setkey, + .init = blake2b_init, + .update = blake2b_update, + .final = blake2b_final, .descsize = sizeof(struct blake2b_state), }, { .base.cra_name = "blake2b-512", @@ -396,21 +274,19 @@ static struct shash_alg blake2b_algs[] = { .base.cra_priority = 100, .base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY, .base.cra_blocksize = BLAKE2B_BLOCKBYTES, - .base.cra_ctxsize = sizeof(struct digest_tfm_ctx), + .base.cra_ctxsize = sizeof(struct blake2b_tfm_ctx), .base.cra_module = THIS_MODULE, .digestsize = BLAKE2B_512_DIGEST_SIZE, - .setkey = digest_setkey, - .init = digest_init, - .update = digest_update, - .final = digest_final, + .setkey = blake2b_setkey, + .init = blake2b_init, + .update = blake2b_update, + .final = blake2b_final, .descsize = sizeof(struct blake2b_state), } }; static int __init blake2b_mod_init(void) { - BUILD_BUG_ON(sizeof(struct blake2b_param) != BLAKE2B_OUTBYTES); - return crypto_register_shashes(blake2b_algs, ARRAY_SIZE(blake2b_algs)); }
On Thu, Oct 24, 2019 at 10:15:50PM -0700, Eric Biggers wrote: > On Thu, Oct 24, 2019 at 06:28:31PM +0200, David Sterba wrote: > > The patch brings support of several BLAKE2 variants (2b with various > > digest lengths). The keyed digest is supported, using tfm->setkey call. > > The in-tree user will be btrfs (for checksumming), we're going to use > > the BLAKE2b-256 variant. > > > > The code is reference implementation taken from the official sources and > > modified in terms of kernel coding style (whitespace, comments, uintXX_t > > -> uXX types, removed unused prototypes and #ifdefs, removed testing > > code, changed secure_zero_memory -> memzero_explicit, used own helpers > > for unaligned reads/writes and rotations). > > > > Further changes removed sanity checks of key length or output size, > > these values are verified in the crypto API callbacks or hardcoded in > > shash_alg and not exposed to users. > > > > Signed-off-by: David Sterba <dsterba@suse.com> > > --- > > crypto/Kconfig | 17 ++ > > crypto/Makefile | 1 + > > crypto/blake2b_generic.c | 435 +++++++++++++++++++++++++++++++++++++++ > > 3 files changed, 453 insertions(+) > > create mode 100644 crypto/blake2b_generic.c > > > > This looks good enough now, though it would be nice to clean up some more of the > cruft that isn't actually needed and add a few of the optimizations from the > BLAKE2s code that is being proposed. E.g. we could easily save 120 lines with > the following: While I see your point, my intention is to avoid changes beyond formatting and interface adjustments so the kernel code would not diverge from the reference one. IMHO having this as a separate commit is a good thing. Further changes would need another round of review(s) and testing and then it should be called 'based on reference code and heavily modified', like the blake2s patch says. The proposed patch looks good, though I'd rather address that independently and perhaps also split it to individual changes so it's clear how the code is transformed.
diff --git a/crypto/Kconfig b/crypto/Kconfig index ad86463de715..d37eba22f436 100644 --- a/crypto/Kconfig +++ b/crypto/Kconfig @@ -610,6 +610,23 @@ config CRYPTO_XXHASH xxHash non-cryptographic hash algorithm. Extremely fast, working at speeds close to RAM limits. +config CRYPTO_BLAKE2B + tristate "BLAKE2b digest algorithm" + select CRYPTO_HASH + help + Implementation of cryptographic hash function BLAKE2b (or just BLAKE2), + optimized for 64bit platforms and can produce digests of any size + between 1 to 64. The keyed hash is also implemented. + + This module provides the following algorithms: + + - blake2b-160 + - blake2b-256 + - blake2b-384 + - blake2b-512 + + See https://blake2.net for further information. + config CRYPTO_CRCT10DIF tristate "CRCT10DIF algorithm" select CRYPTO_HASH diff --git a/crypto/Makefile b/crypto/Makefile index 0d2cdd523fd9..dc010b1a8e41 100644 --- a/crypto/Makefile +++ b/crypto/Makefile @@ -74,6 +74,7 @@ obj-$(CONFIG_CRYPTO_STREEBOG) += streebog_generic.o obj-$(CONFIG_CRYPTO_WP512) += wp512.o CFLAGS_wp512.o := $(call cc-option,-fno-schedule-insns) # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79149 obj-$(CONFIG_CRYPTO_TGR192) += tgr192.o +obj-$(CONFIG_CRYPTO_BLAKE2B) += blake2b_generic.o obj-$(CONFIG_CRYPTO_GF128MUL) += gf128mul.o obj-$(CONFIG_CRYPTO_ECB) += ecb.o obj-$(CONFIG_CRYPTO_CBC) += cbc.o diff --git a/crypto/blake2b_generic.c b/crypto/blake2b_generic.c new file mode 100644 index 000000000000..8dab65612a41 --- /dev/null +++ b/crypto/blake2b_generic.c @@ -0,0 +1,435 @@ +// SPDX-License-Identifier: (GPL-2.0-only OR Apache-2.0) +/* + * BLAKE2b reference source code package - reference C implementations + * + * Copyright 2012, Samuel Neves <sneves@dei.uc.pt>. You may use this under the + * terms of the CC0, the OpenSSL Licence, or the Apache Public License 2.0, at + * your option. The terms of these licenses can be found at: + * + * - CC0 1.0 Universal : http://creativecommons.org/publicdomain/zero/1.0 + * - OpenSSL license : https://www.openssl.org/source/license.html + * - Apache 2.0 : http://www.apache.org/licenses/LICENSE-2.0 + * + * More information about the BLAKE2 hash function can be found at + * https://blake2.net. + * + * Note: the original sources have been modified for inclusion in linux kernel + * in terms of coding style, using generic helpers and simplifications of error + * handling. + */ + +#include <asm/unaligned.h> +#include <linux/module.h> +#include <linux/string.h> +#include <linux/kernel.h> +#include <linux/bitops.h> +#include <crypto/internal/hash.h> + +#define BLAKE2B_160_DIGEST_SIZE (160 / 8) +#define BLAKE2B_256_DIGEST_SIZE (256 / 8) +#define BLAKE2B_384_DIGEST_SIZE (384 / 8) +#define BLAKE2B_512_DIGEST_SIZE (512 / 8) + +enum blake2b_constant { + BLAKE2B_BLOCKBYTES = 128, + BLAKE2B_OUTBYTES = 64, + BLAKE2B_KEYBYTES = 64, + BLAKE2B_SALTBYTES = 16, + BLAKE2B_PERSONALBYTES = 16 +}; + +struct blake2b_state { + u64 h[8]; + u64 t[2]; + u64 f[2]; + u8 buf[BLAKE2B_BLOCKBYTES]; + size_t buflen; + size_t outlen; + u8 last_node; +}; + +struct blake2b_param { + u8 digest_length; /* 1 */ + u8 key_length; /* 2 */ + u8 fanout; /* 3 */ + u8 depth; /* 4 */ + __le32 leaf_length; /* 8 */ + __le32 node_offset; /* 12 */ + __le32 xof_length; /* 16 */ + u8 node_depth; /* 17 */ + u8 inner_length; /* 18 */ + u8 reserved[14]; /* 32 */ + u8 salt[BLAKE2B_SALTBYTES]; /* 48 */ + u8 personal[BLAKE2B_PERSONALBYTES]; /* 64 */ +} __packed; + +static const u64 blake2b_IV[8] = { + 0x6a09e667f3bcc908ULL, 0xbb67ae8584caa73bULL, + 0x3c6ef372fe94f82bULL, 0xa54ff53a5f1d36f1ULL, + 0x510e527fade682d1ULL, 0x9b05688c2b3e6c1fULL, + 0x1f83d9abfb41bd6bULL, 0x5be0cd19137e2179ULL +}; + +static const u8 blake2b_sigma[12][16] = { + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 }, + { 14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3 }, + { 11, 8, 12, 0, 5, 2, 15, 13, 10, 14, 3, 6, 7, 1, 9, 4 }, + { 7, 9, 3, 1, 13, 12, 11, 14, 2, 6, 5, 10, 4, 0, 15, 8 }, + { 9, 0, 5, 7, 2, 4, 10, 15, 14, 1, 11, 12, 6, 8, 3, 13 }, + { 2, 12, 6, 10, 0, 11, 8, 3, 4, 13, 7, 5, 15, 14, 1, 9 }, + { 12, 5, 1, 15, 14, 13, 4, 10, 0, 7, 6, 3, 9, 2, 8, 11 }, + { 13, 11, 7, 14, 12, 1, 3, 9, 5, 0, 15, 4, 8, 6, 2, 10 }, + { 6, 15, 14, 9, 11, 3, 0, 8, 12, 2, 13, 7, 1, 4, 10, 5 }, + { 10, 2, 8, 4, 7, 6, 1, 5, 15, 11, 9, 14, 3, 12, 13, 0 }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 }, + { 14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3 } +}; + +static void blake2b_update(struct blake2b_state *S, const void *pin, size_t inlen); + +static void blake2b_set_lastnode(struct blake2b_state *S) +{ + S->f[1] = (u64)-1; +} + +static void blake2b_set_lastblock(struct blake2b_state *S) +{ + if (S->last_node) + blake2b_set_lastnode(S); + + S->f[0] = (u64)-1; +} + +static void blake2b_increment_counter(struct blake2b_state *S, const u64 inc) +{ + S->t[0] += inc; + S->t[1] += (S->t[0] < inc); +} + +static void blake2b_init0(struct blake2b_state *S) +{ + size_t i; + + memset(S, 0, sizeof(struct blake2b_state)); + + for (i = 0; i < 8; ++i) + S->h[i] = blake2b_IV[i]; +} + +/* init xors IV with input parameter block */ +static void blake2b_init_param(struct blake2b_state *S, + const struct blake2b_param *P) +{ + const u8 *p = (const u8 *)(P); + size_t i; + + blake2b_init0(S); + + /* IV XOR ParamBlock */ + for (i = 0; i < 8; ++i) + S->h[i] ^= get_unaligned_le64(p + sizeof(S->h[i]) * i); + + S->outlen = P->digest_length; +} + +static void blake2b_init(struct blake2b_state *S, size_t outlen) +{ + struct blake2b_param P; + + P.digest_length = (u8)outlen; + P.key_length = 0; + P.fanout = 1; + P.depth = 1; + P.leaf_length = 0; + P.node_offset = 0; + P.xof_length = 0; + P.node_depth = 0; + P.inner_length = 0; + memset(P.reserved, 0, sizeof(P.reserved)); + memset(P.salt, 0, sizeof(P.salt)); + memset(P.personal, 0, sizeof(P.personal)); + blake2b_init_param(S, &P); +} + +static void blake2b_init_key(struct blake2b_state *S, size_t outlen, + const void *key, size_t keylen) +{ + struct blake2b_param P; + + P.digest_length = (u8)outlen; + P.key_length = (u8)keylen; + P.fanout = 1; + P.depth = 1; + P.leaf_length = 0; + P.node_offset = 0; + P.xof_length = 0; + P.node_depth = 0; + P.inner_length = 0; + memset(P.reserved, 0, sizeof(P.reserved)); + memset(P.salt, 0, sizeof(P.salt)); + memset(P.personal, 0, sizeof(P.personal)); + + blake2b_init_param(S, &P); + + { + u8 block[BLAKE2B_BLOCKBYTES]; + + memset(block, 0, BLAKE2B_BLOCKBYTES); + memcpy(block, key, keylen); + blake2b_update(S, block, BLAKE2B_BLOCKBYTES); + memzero_explicit(block, BLAKE2B_BLOCKBYTES); + } +} + +#define G(r,i,a,b,c,d) \ + do { \ + a = a + b + m[blake2b_sigma[r][2*i+0]]; \ + d = ror64(d ^ a, 32); \ + c = c + d; \ + b = ror64(b ^ c, 24); \ + a = a + b + m[blake2b_sigma[r][2*i+1]]; \ + d = ror64(d ^ a, 16); \ + c = c + d; \ + b = ror64(b ^ c, 63); \ + } while (0) + +#define ROUND(r) \ + do { \ + G(r,0,v[ 0],v[ 4],v[ 8],v[12]); \ + G(r,1,v[ 1],v[ 5],v[ 9],v[13]); \ + G(r,2,v[ 2],v[ 6],v[10],v[14]); \ + G(r,3,v[ 3],v[ 7],v[11],v[15]); \ + G(r,4,v[ 0],v[ 5],v[10],v[15]); \ + G(r,5,v[ 1],v[ 6],v[11],v[12]); \ + G(r,6,v[ 2],v[ 7],v[ 8],v[13]); \ + G(r,7,v[ 3],v[ 4],v[ 9],v[14]); \ + } while (0) + +static void blake2b_compress(struct blake2b_state *S, + const u8 block[BLAKE2B_BLOCKBYTES]) +{ + u64 m[16]; + u64 v[16]; + size_t i; + + for (i = 0; i < 16; ++i) + m[i] = get_unaligned_le64(block + i * sizeof(m[i])); + + for (i = 0; i < 8; ++i) + v[i] = S->h[i]; + + v[ 8] = blake2b_IV[0]; + v[ 9] = blake2b_IV[1]; + v[10] = blake2b_IV[2]; + v[11] = blake2b_IV[3]; + v[12] = blake2b_IV[4] ^ S->t[0]; + v[13] = blake2b_IV[5] ^ S->t[1]; + v[14] = blake2b_IV[6] ^ S->f[0]; + v[15] = blake2b_IV[7] ^ S->f[1]; + + ROUND(0); + ROUND(1); + ROUND(2); + ROUND(3); + ROUND(4); + ROUND(5); + ROUND(6); + ROUND(7); + ROUND(8); + ROUND(9); + ROUND(10); + ROUND(11); + + for (i = 0; i < 8; ++i) + S->h[i] = S->h[i] ^ v[i] ^ v[i + 8]; +} + +#undef G +#undef ROUND + +static void blake2b_update(struct blake2b_state *S, const void *pin, size_t inlen) +{ + const u8 *in = (const u8 *)pin; + + if (inlen > 0) { + size_t left = S->buflen; + size_t fill = BLAKE2B_BLOCKBYTES - left; + + if (inlen > fill) { + S->buflen = 0; + /* Fill buffer */ + memcpy(S->buf + left, in, fill); + blake2b_increment_counter(S, BLAKE2B_BLOCKBYTES); + /* Compress */ + blake2b_compress(S, S->buf); + in += fill; + inlen -= fill; + while (inlen > BLAKE2B_BLOCKBYTES) { + blake2b_increment_counter(S, BLAKE2B_BLOCKBYTES); + blake2b_compress(S, in); + in += BLAKE2B_BLOCKBYTES; + inlen -= BLAKE2B_BLOCKBYTES; + } + } + memcpy(S->buf + S->buflen, in, inlen); + S->buflen += inlen; + } +} + +static void blake2b_final(struct blake2b_state *S, void *out, size_t outlen) +{ + u8 buffer[BLAKE2B_OUTBYTES] = {0}; + size_t i; + + blake2b_increment_counter(S, S->buflen); + blake2b_set_lastblock(S); + /* Padding */ + memset(S->buf + S->buflen, 0, BLAKE2B_BLOCKBYTES - S->buflen); + blake2b_compress(S, S->buf); + + /* Output full hash to temp buffer */ + for (i = 0; i < 8; ++i) + put_unaligned_le64(S->h[i], buffer + sizeof(S->h[i]) * i); + + memcpy(out, buffer, S->outlen); + memzero_explicit(buffer, sizeof(buffer)); +} + +struct digest_tfm_ctx { + u8 key[BLAKE2B_KEYBYTES]; + unsigned int keylen; +}; + +static int digest_setkey(struct crypto_shash *tfm, const u8 *key, + unsigned int keylen) +{ + struct digest_tfm_ctx *mctx = crypto_shash_ctx(tfm); + + if (keylen == 0 || keylen > BLAKE2B_KEYBYTES) { + crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); + return -EINVAL; + } + + memcpy(mctx->key, key, keylen); + mctx->keylen = keylen; + + return 0; +} + +static int digest_init(struct shash_desc *desc) +{ + struct digest_tfm_ctx *mctx = crypto_shash_ctx(desc->tfm); + struct blake2b_state *state = shash_desc_ctx(desc); + const int digestsize = crypto_shash_digestsize(desc->tfm); + + if (mctx->keylen == 0) + blake2b_init(state, digestsize); + else + blake2b_init_key(state, digestsize, mctx->key, mctx->keylen); + return 0; +} + +static int digest_update(struct shash_desc *desc, const u8 *data, + unsigned int length) +{ + struct blake2b_state *state = shash_desc_ctx(desc); + + blake2b_update(state, data, length); + return 0; +} + +static int digest_final(struct shash_desc *desc, u8 *out) +{ + struct blake2b_state *state = shash_desc_ctx(desc); + const int digestsize = crypto_shash_digestsize(desc->tfm); + + blake2b_final(state, out, digestsize); + return 0; +} + +static struct shash_alg blake2b_algs[] = { + { + .base.cra_name = "blake2b-160", + .base.cra_driver_name = "blake2b-160-generic", + .base.cra_priority = 100, + .base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY, + .base.cra_blocksize = BLAKE2B_BLOCKBYTES, + .base.cra_ctxsize = sizeof(struct digest_tfm_ctx), + .base.cra_module = THIS_MODULE, + .digestsize = BLAKE2B_160_DIGEST_SIZE, + .setkey = digest_setkey, + .init = digest_init, + .update = digest_update, + .final = digest_final, + .descsize = sizeof(struct blake2b_state), + }, { + .base.cra_name = "blake2b-256", + .base.cra_driver_name = "blake2b-256-generic", + .base.cra_priority = 100, + .base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY, + .base.cra_blocksize = BLAKE2B_BLOCKBYTES, + .base.cra_ctxsize = sizeof(struct digest_tfm_ctx), + .base.cra_module = THIS_MODULE, + .digestsize = BLAKE2B_256_DIGEST_SIZE, + .setkey = digest_setkey, + .init = digest_init, + .update = digest_update, + .final = digest_final, + .descsize = sizeof(struct blake2b_state), + }, { + .base.cra_name = "blake2b-384", + .base.cra_driver_name = "blake2b-384-generic", + .base.cra_priority = 100, + .base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY, + .base.cra_blocksize = BLAKE2B_BLOCKBYTES, + .base.cra_ctxsize = sizeof(struct digest_tfm_ctx), + .base.cra_module = THIS_MODULE, + .digestsize = BLAKE2B_384_DIGEST_SIZE, + .setkey = digest_setkey, + .init = digest_init, + .update = digest_update, + .final = digest_final, + .descsize = sizeof(struct blake2b_state), + }, { + .base.cra_name = "blake2b-512", + .base.cra_driver_name = "blake2b-512-generic", + .base.cra_priority = 100, + .base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY, + .base.cra_blocksize = BLAKE2B_BLOCKBYTES, + .base.cra_ctxsize = sizeof(struct digest_tfm_ctx), + .base.cra_module = THIS_MODULE, + .digestsize = BLAKE2B_512_DIGEST_SIZE, + .setkey = digest_setkey, + .init = digest_init, + .update = digest_update, + .final = digest_final, + .descsize = sizeof(struct blake2b_state), + } +}; + +static int __init blake2b_mod_init(void) +{ + BUILD_BUG_ON(sizeof(struct blake2b_param) != BLAKE2B_OUTBYTES); + + return crypto_register_shashes(blake2b_algs, ARRAY_SIZE(blake2b_algs)); +} + +static void __exit blake2b_mod_fini(void) +{ + crypto_unregister_shashes(blake2b_algs, ARRAY_SIZE(blake2b_algs)); +} + +subsys_initcall(blake2b_mod_init); +module_exit(blake2b_mod_fini); + +MODULE_AUTHOR("David Sterba <kdave@kernel.org>"); +MODULE_DESCRIPTION("BLAKE2b generic implementation"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_CRYPTO("blake2b-160"); +MODULE_ALIAS_CRYPTO("blake2b-160-generic"); +MODULE_ALIAS_CRYPTO("blake2b-256"); +MODULE_ALIAS_CRYPTO("blake2b-256-generic"); +MODULE_ALIAS_CRYPTO("blake2b-384"); +MODULE_ALIAS_CRYPTO("blake2b-384-generic"); +MODULE_ALIAS_CRYPTO("blake2b-512"); +MODULE_ALIAS_CRYPTO("blake2b-512-generic");
The patch brings support of several BLAKE2 variants (2b with various digest lengths). The keyed digest is supported, using tfm->setkey call. The in-tree user will be btrfs (for checksumming), we're going to use the BLAKE2b-256 variant. The code is reference implementation taken from the official sources and modified in terms of kernel coding style (whitespace, comments, uintXX_t -> uXX types, removed unused prototypes and #ifdefs, removed testing code, changed secure_zero_memory -> memzero_explicit, used own helpers for unaligned reads/writes and rotations). Further changes removed sanity checks of key length or output size, these values are verified in the crypto API callbacks or hardcoded in shash_alg and not exposed to users. Signed-off-by: David Sterba <dsterba@suse.com> --- crypto/Kconfig | 17 ++ crypto/Makefile | 1 + crypto/blake2b_generic.c | 435 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 453 insertions(+) create mode 100644 crypto/blake2b_generic.c