Return-Path: Received: from mail-it1-f195.google.com ([209.85.166.195]:33157 "EHLO mail-it1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727641AbeJSWcE (ORCPT ); Fri, 19 Oct 2018 18:32:04 -0400 Received: by mail-it1-f195.google.com with SMTP id h6-v6so4405663ith.0 for ; Fri, 19 Oct 2018 07:25:41 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20181015175424.97147-4-ebiggers@kernel.org> References: <20181015175424.97147-1-ebiggers@kernel.org> <20181015175424.97147-4-ebiggers@kernel.org> From: Ard Biesheuvel Date: Fri, 19 Oct 2018 22:25:40 +0800 Message-ID: Subject: Re: [RFC PATCH v2 03/12] crypto: chacha20-generic - refactor to allow varying number of rounds To: Eric Biggers Cc: "open list:HARDWARE RANDOM NUMBER GENERATOR CORE" , linux-fscrypt@vger.kernel.org, linux-arm-kernel , Linux Kernel Mailing List , Herbert Xu , Paul Crowley , Greg Kaiser , Michael Halcrow , "Jason A . Donenfeld" , Samuel Neves , Tomer Ashur Content-Type: text/plain; charset="UTF-8" Sender: linux-crypto-owner@vger.kernel.org List-ID: On 16 October 2018 at 01:54, Eric Biggers wrote: > From: Eric Biggers > > In preparation for adding XChaCha12 support, rename/refactor > chacha20-generic to support different numbers of rounds. The > justification for needing XChaCha12 support is explained in more detail > in the patch "crypto: chacha - add XChaCha12 support". > > The only difference between ChaCha{8,12,20} are the number of rounds > itself; all other parts of the algorithm are the same. Therefore, > remove the "20" from all definitions, structures, functions, files, etc. > that will be shared by all ChaCha versions. > > Also make ->setkey() store the round count in the chacha_ctx (previously > chacha20_ctx). The generic code then passes the round count through to > chacha_block(). There will be a ->setkey() function for each explicitly > allowed round count; the encrypt/decrypt functions will be the same. I > decided not to do it the opposite way (same ->setkey() function for all > round counts, with different encrypt/decrypt functions) because that > would have required more boilerplate code in architecture-specific > implementations of ChaCha and XChaCha. > > To be as careful as possible, we whitelist the allowed round counts in > the low-level generic code. Currently only 20 is allowed, i.e. no > actual use of other variants is introduced by this patch. > > Signed-off-by: Eric Biggers Reviewed-by: Ard Biesheuvel > --- > arch/arm/crypto/chacha20-neon-glue.c | 40 +++---- > arch/arm64/crypto/chacha20-neon-glue.c | 40 +++---- > arch/x86/crypto/chacha20_glue.c | 52 ++++----- > crypto/Makefile | 2 +- > crypto/chacha20poly1305.c | 10 +- > .../{chacha20_generic.c => chacha_generic.c} | 110 ++++++++++-------- > drivers/char/random.c | 51 ++++---- > include/crypto/chacha.h | 46 ++++++++ > include/crypto/chacha20.h | 41 ------- > lib/Makefile | 2 +- > lib/{chacha20.c => chacha.c} | 43 ++++--- > 11 files changed, 227 insertions(+), 210 deletions(-) > rename crypto/{chacha20_generic.c => chacha_generic.c} (57%) > create mode 100644 include/crypto/chacha.h > delete mode 100644 include/crypto/chacha20.h > rename lib/{chacha20.c => chacha.c} (67%) > > diff --git a/arch/arm/crypto/chacha20-neon-glue.c b/arch/arm/crypto/chacha20-neon-glue.c > index 59a7be08e80ce..7386eb1c1889d 100644 > --- a/arch/arm/crypto/chacha20-neon-glue.c > +++ b/arch/arm/crypto/chacha20-neon-glue.c > @@ -19,7 +19,7 @@ > */ > > #include > -#include > +#include > #include > #include > #include > @@ -34,20 +34,20 @@ asmlinkage void chacha20_4block_xor_neon(u32 *state, u8 *dst, const u8 *src); > static void chacha20_doneon(u32 *state, u8 *dst, const u8 *src, > unsigned int bytes) > { > - u8 buf[CHACHA20_BLOCK_SIZE]; > + u8 buf[CHACHA_BLOCK_SIZE]; > > - while (bytes >= CHACHA20_BLOCK_SIZE * 4) { > + while (bytes >= CHACHA_BLOCK_SIZE * 4) { > chacha20_4block_xor_neon(state, dst, src); > - bytes -= CHACHA20_BLOCK_SIZE * 4; > - src += CHACHA20_BLOCK_SIZE * 4; > - dst += CHACHA20_BLOCK_SIZE * 4; > + bytes -= CHACHA_BLOCK_SIZE * 4; > + src += CHACHA_BLOCK_SIZE * 4; > + dst += CHACHA_BLOCK_SIZE * 4; > state[12] += 4; > } > - while (bytes >= CHACHA20_BLOCK_SIZE) { > + while (bytes >= CHACHA_BLOCK_SIZE) { > chacha20_block_xor_neon(state, dst, src); > - bytes -= CHACHA20_BLOCK_SIZE; > - src += CHACHA20_BLOCK_SIZE; > - dst += CHACHA20_BLOCK_SIZE; > + bytes -= CHACHA_BLOCK_SIZE; > + src += CHACHA_BLOCK_SIZE; > + dst += CHACHA_BLOCK_SIZE; > state[12]++; > } > if (bytes) { > @@ -60,17 +60,17 @@ static void chacha20_doneon(u32 *state, u8 *dst, const u8 *src, > static int chacha20_neon(struct skcipher_request *req) > { > struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); > - struct chacha20_ctx *ctx = crypto_skcipher_ctx(tfm); > + struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm); > struct skcipher_walk walk; > u32 state[16]; > int err; > > - if (req->cryptlen <= CHACHA20_BLOCK_SIZE || !may_use_simd()) > - return crypto_chacha20_crypt(req); > + if (req->cryptlen <= CHACHA_BLOCK_SIZE || !may_use_simd()) > + return crypto_chacha_crypt(req); > > err = skcipher_walk_virt(&walk, req, true); > > - crypto_chacha20_init(state, ctx, walk.iv); > + crypto_chacha_init(state, ctx, walk.iv); > > kernel_neon_begin(); > while (walk.nbytes > 0) { > @@ -93,14 +93,14 @@ static struct skcipher_alg alg = { > .base.cra_driver_name = "chacha20-neon", > .base.cra_priority = 300, > .base.cra_blocksize = 1, > - .base.cra_ctxsize = sizeof(struct chacha20_ctx), > + .base.cra_ctxsize = sizeof(struct chacha_ctx), > .base.cra_module = THIS_MODULE, > > - .min_keysize = CHACHA20_KEY_SIZE, > - .max_keysize = CHACHA20_KEY_SIZE, > - .ivsize = CHACHA20_IV_SIZE, > - .chunksize = CHACHA20_BLOCK_SIZE, > - .walksize = 4 * CHACHA20_BLOCK_SIZE, > + .min_keysize = CHACHA_KEY_SIZE, > + .max_keysize = CHACHA_KEY_SIZE, > + .ivsize = CHACHA_IV_SIZE, > + .chunksize = CHACHA_BLOCK_SIZE, > + .walksize = 4 * CHACHA_BLOCK_SIZE, > .setkey = crypto_chacha20_setkey, > .encrypt = chacha20_neon, > .decrypt = chacha20_neon, > diff --git a/arch/arm64/crypto/chacha20-neon-glue.c b/arch/arm64/crypto/chacha20-neon-glue.c > index 727579c93dedb..96e0cfb8c3f5b 100644 > --- a/arch/arm64/crypto/chacha20-neon-glue.c > +++ b/arch/arm64/crypto/chacha20-neon-glue.c > @@ -19,7 +19,7 @@ > */ > > #include > -#include > +#include > #include > #include > #include > @@ -34,15 +34,15 @@ asmlinkage void chacha20_4block_xor_neon(u32 *state, u8 *dst, const u8 *src); > static void chacha20_doneon(u32 *state, u8 *dst, const u8 *src, > unsigned int bytes) > { > - u8 buf[CHACHA20_BLOCK_SIZE]; > + u8 buf[CHACHA_BLOCK_SIZE]; > > - while (bytes >= CHACHA20_BLOCK_SIZE * 4) { > + while (bytes >= CHACHA_BLOCK_SIZE * 4) { > kernel_neon_begin(); > chacha20_4block_xor_neon(state, dst, src); > kernel_neon_end(); > - bytes -= CHACHA20_BLOCK_SIZE * 4; > - src += CHACHA20_BLOCK_SIZE * 4; > - dst += CHACHA20_BLOCK_SIZE * 4; > + bytes -= CHACHA_BLOCK_SIZE * 4; > + src += CHACHA_BLOCK_SIZE * 4; > + dst += CHACHA_BLOCK_SIZE * 4; > state[12] += 4; > } > > @@ -50,11 +50,11 @@ static void chacha20_doneon(u32 *state, u8 *dst, const u8 *src, > return; > > kernel_neon_begin(); > - while (bytes >= CHACHA20_BLOCK_SIZE) { > + while (bytes >= CHACHA_BLOCK_SIZE) { > chacha20_block_xor_neon(state, dst, src); > - bytes -= CHACHA20_BLOCK_SIZE; > - src += CHACHA20_BLOCK_SIZE; > - dst += CHACHA20_BLOCK_SIZE; > + bytes -= CHACHA_BLOCK_SIZE; > + src += CHACHA_BLOCK_SIZE; > + dst += CHACHA_BLOCK_SIZE; > state[12]++; > } > if (bytes) { > @@ -68,17 +68,17 @@ static void chacha20_doneon(u32 *state, u8 *dst, const u8 *src, > static int chacha20_neon(struct skcipher_request *req) > { > struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); > - struct chacha20_ctx *ctx = crypto_skcipher_ctx(tfm); > + struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm); > struct skcipher_walk walk; > u32 state[16]; > int err; > > - if (!may_use_simd() || req->cryptlen <= CHACHA20_BLOCK_SIZE) > - return crypto_chacha20_crypt(req); > + if (!may_use_simd() || req->cryptlen <= CHACHA_BLOCK_SIZE) > + return crypto_chacha_crypt(req); > > err = skcipher_walk_virt(&walk, req, false); > > - crypto_chacha20_init(state, ctx, walk.iv); > + crypto_chacha_init(state, ctx, walk.iv); > > while (walk.nbytes > 0) { > unsigned int nbytes = walk.nbytes; > @@ -99,14 +99,14 @@ static struct skcipher_alg alg = { > .base.cra_driver_name = "chacha20-neon", > .base.cra_priority = 300, > .base.cra_blocksize = 1, > - .base.cra_ctxsize = sizeof(struct chacha20_ctx), > + .base.cra_ctxsize = sizeof(struct chacha_ctx), > .base.cra_module = THIS_MODULE, > > - .min_keysize = CHACHA20_KEY_SIZE, > - .max_keysize = CHACHA20_KEY_SIZE, > - .ivsize = CHACHA20_IV_SIZE, > - .chunksize = CHACHA20_BLOCK_SIZE, > - .walksize = 4 * CHACHA20_BLOCK_SIZE, > + .min_keysize = CHACHA_KEY_SIZE, > + .max_keysize = CHACHA_KEY_SIZE, > + .ivsize = CHACHA_IV_SIZE, > + .chunksize = CHACHA_BLOCK_SIZE, > + .walksize = 4 * CHACHA_BLOCK_SIZE, > .setkey = crypto_chacha20_setkey, > .encrypt = chacha20_neon, > .decrypt = chacha20_neon, > diff --git a/arch/x86/crypto/chacha20_glue.c b/arch/x86/crypto/chacha20_glue.c > index dce7c5d39c2f2..bd249f0b29dc2 100644 > --- a/arch/x86/crypto/chacha20_glue.c > +++ b/arch/x86/crypto/chacha20_glue.c > @@ -10,7 +10,7 @@ > */ > > #include > -#include > +#include > #include > #include > #include > @@ -29,31 +29,31 @@ static bool chacha20_use_avx2; > static void chacha20_dosimd(u32 *state, u8 *dst, const u8 *src, > unsigned int bytes) > { > - u8 buf[CHACHA20_BLOCK_SIZE]; > + u8 buf[CHACHA_BLOCK_SIZE]; > > #ifdef CONFIG_AS_AVX2 > if (chacha20_use_avx2) { > - while (bytes >= CHACHA20_BLOCK_SIZE * 8) { > + while (bytes >= CHACHA_BLOCK_SIZE * 8) { > chacha20_8block_xor_avx2(state, dst, src); > - bytes -= CHACHA20_BLOCK_SIZE * 8; > - src += CHACHA20_BLOCK_SIZE * 8; > - dst += CHACHA20_BLOCK_SIZE * 8; > + bytes -= CHACHA_BLOCK_SIZE * 8; > + src += CHACHA_BLOCK_SIZE * 8; > + dst += CHACHA_BLOCK_SIZE * 8; > state[12] += 8; > } > } > #endif > - while (bytes >= CHACHA20_BLOCK_SIZE * 4) { > + while (bytes >= CHACHA_BLOCK_SIZE * 4) { > chacha20_4block_xor_ssse3(state, dst, src); > - bytes -= CHACHA20_BLOCK_SIZE * 4; > - src += CHACHA20_BLOCK_SIZE * 4; > - dst += CHACHA20_BLOCK_SIZE * 4; > + bytes -= CHACHA_BLOCK_SIZE * 4; > + src += CHACHA_BLOCK_SIZE * 4; > + dst += CHACHA_BLOCK_SIZE * 4; > state[12] += 4; > } > - while (bytes >= CHACHA20_BLOCK_SIZE) { > + while (bytes >= CHACHA_BLOCK_SIZE) { > chacha20_block_xor_ssse3(state, dst, src); > - bytes -= CHACHA20_BLOCK_SIZE; > - src += CHACHA20_BLOCK_SIZE; > - dst += CHACHA20_BLOCK_SIZE; > + bytes -= CHACHA_BLOCK_SIZE; > + src += CHACHA_BLOCK_SIZE; > + dst += CHACHA_BLOCK_SIZE; > state[12]++; > } > if (bytes) { > @@ -66,7 +66,7 @@ static void chacha20_dosimd(u32 *state, u8 *dst, const u8 *src, > static int chacha20_simd(struct skcipher_request *req) > { > struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); > - struct chacha20_ctx *ctx = crypto_skcipher_ctx(tfm); > + struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm); > u32 *state, state_buf[16 + 2] __aligned(8); > struct skcipher_walk walk; > int err; > @@ -74,20 +74,20 @@ static int chacha20_simd(struct skcipher_request *req) > BUILD_BUG_ON(CHACHA20_STATE_ALIGN != 16); > state = PTR_ALIGN(state_buf + 0, CHACHA20_STATE_ALIGN); > > - if (req->cryptlen <= CHACHA20_BLOCK_SIZE || !may_use_simd()) > - return crypto_chacha20_crypt(req); > + if (req->cryptlen <= CHACHA_BLOCK_SIZE || !may_use_simd()) > + return crypto_chacha_crypt(req); > > err = skcipher_walk_virt(&walk, req, true); > > - crypto_chacha20_init(state, ctx, walk.iv); > + crypto_chacha_init(state, ctx, walk.iv); > > kernel_fpu_begin(); > > - while (walk.nbytes >= CHACHA20_BLOCK_SIZE) { > + while (walk.nbytes >= CHACHA_BLOCK_SIZE) { > chacha20_dosimd(state, walk.dst.virt.addr, walk.src.virt.addr, > - rounddown(walk.nbytes, CHACHA20_BLOCK_SIZE)); > + rounddown(walk.nbytes, CHACHA_BLOCK_SIZE)); > err = skcipher_walk_done(&walk, > - walk.nbytes % CHACHA20_BLOCK_SIZE); > + walk.nbytes % CHACHA_BLOCK_SIZE); > } > > if (walk.nbytes) { > @@ -106,13 +106,13 @@ static struct skcipher_alg alg = { > .base.cra_driver_name = "chacha20-simd", > .base.cra_priority = 300, > .base.cra_blocksize = 1, > - .base.cra_ctxsize = sizeof(struct chacha20_ctx), > + .base.cra_ctxsize = sizeof(struct chacha_ctx), > .base.cra_module = THIS_MODULE, > > - .min_keysize = CHACHA20_KEY_SIZE, > - .max_keysize = CHACHA20_KEY_SIZE, > - .ivsize = CHACHA20_IV_SIZE, > - .chunksize = CHACHA20_BLOCK_SIZE, > + .min_keysize = CHACHA_KEY_SIZE, > + .max_keysize = CHACHA_KEY_SIZE, > + .ivsize = CHACHA_IV_SIZE, > + .chunksize = CHACHA_BLOCK_SIZE, > .setkey = crypto_chacha20_setkey, > .encrypt = chacha20_simd, > .decrypt = chacha20_simd, > diff --git a/crypto/Makefile b/crypto/Makefile > index 5c207c76abf7e..7e673f7c71107 100644 > --- a/crypto/Makefile > +++ b/crypto/Makefile > @@ -116,7 +116,7 @@ obj-$(CONFIG_CRYPTO_KHAZAD) += khazad.o > obj-$(CONFIG_CRYPTO_ANUBIS) += anubis.o > obj-$(CONFIG_CRYPTO_SEED) += seed.o > obj-$(CONFIG_CRYPTO_SALSA20) += salsa20_generic.o > -obj-$(CONFIG_CRYPTO_CHACHA20) += chacha20_generic.o > +obj-$(CONFIG_CRYPTO_CHACHA20) += chacha_generic.o > obj-$(CONFIG_CRYPTO_POLY1305) += poly1305_generic.o > obj-$(CONFIG_CRYPTO_DEFLATE) += deflate.o > obj-$(CONFIG_CRYPTO_MICHAEL_MIC) += michael_mic.o > diff --git a/crypto/chacha20poly1305.c b/crypto/chacha20poly1305.c > index 600afa99941fe..573c07e6f189e 100644 > --- a/crypto/chacha20poly1305.c > +++ b/crypto/chacha20poly1305.c > @@ -13,7 +13,7 @@ > #include > #include > #include > -#include > +#include > #include > #include > #include > @@ -51,7 +51,7 @@ struct poly_req { > }; > > struct chacha_req { > - u8 iv[CHACHA20_IV_SIZE]; > + u8 iv[CHACHA_IV_SIZE]; > struct scatterlist src[1]; > struct skcipher_request req; /* must be last member */ > }; > @@ -91,7 +91,7 @@ static void chacha_iv(u8 *iv, struct aead_request *req, u32 icb) > memcpy(iv, &leicb, sizeof(leicb)); > memcpy(iv + sizeof(leicb), ctx->salt, ctx->saltlen); > memcpy(iv + sizeof(leicb) + ctx->saltlen, req->iv, > - CHACHA20_IV_SIZE - sizeof(leicb) - ctx->saltlen); > + CHACHA_IV_SIZE - sizeof(leicb) - ctx->saltlen); > } > > static int poly_verify_tag(struct aead_request *req) > @@ -494,7 +494,7 @@ static int chachapoly_setkey(struct crypto_aead *aead, const u8 *key, > struct chachapoly_ctx *ctx = crypto_aead_ctx(aead); > int err; > > - if (keylen != ctx->saltlen + CHACHA20_KEY_SIZE) > + if (keylen != ctx->saltlen + CHACHA_KEY_SIZE) > return -EINVAL; > > keylen -= ctx->saltlen; > @@ -639,7 +639,7 @@ static int chachapoly_create(struct crypto_template *tmpl, struct rtattr **tb, > > err = -EINVAL; > /* Need 16-byte IV size, including Initial Block Counter value */ > - if (crypto_skcipher_alg_ivsize(chacha) != CHACHA20_IV_SIZE) > + if (crypto_skcipher_alg_ivsize(chacha) != CHACHA_IV_SIZE) > goto out_drop_chacha; > /* Not a stream cipher? */ > if (chacha->base.cra_blocksize != 1) > diff --git a/crypto/chacha20_generic.c b/crypto/chacha_generic.c > similarity index 57% > rename from crypto/chacha20_generic.c > rename to crypto/chacha_generic.c > index 07902fe37aeb8..8e25e9930c549 100644 > --- a/crypto/chacha20_generic.c > +++ b/crypto/chacha_generic.c > @@ -12,33 +12,33 @@ > > #include > #include > -#include > +#include > #include > #include > > -static void chacha20_docrypt(u32 *state, u8 *dst, const u8 *src, > - unsigned int bytes) > +static void chacha_docrypt(u32 *state, u8 *dst, const u8 *src, > + unsigned int bytes, int nrounds) > { > /* aligned to potentially speed up crypto_xor() */ > - u8 stream[CHACHA20_BLOCK_SIZE] __aligned(sizeof(long)); > + u8 stream[CHACHA_BLOCK_SIZE] __aligned(sizeof(long)); > > if (dst != src) > memcpy(dst, src, bytes); > > - while (bytes >= CHACHA20_BLOCK_SIZE) { > - chacha20_block(state, stream); > - crypto_xor(dst, stream, CHACHA20_BLOCK_SIZE); > - bytes -= CHACHA20_BLOCK_SIZE; > - dst += CHACHA20_BLOCK_SIZE; > + while (bytes >= CHACHA_BLOCK_SIZE) { > + chacha_block(state, stream, nrounds); > + crypto_xor(dst, stream, CHACHA_BLOCK_SIZE); > + bytes -= CHACHA_BLOCK_SIZE; > + dst += CHACHA_BLOCK_SIZE; > } > if (bytes) { > - chacha20_block(state, stream); > + chacha_block(state, stream, nrounds); > crypto_xor(dst, stream, bytes); > } > } > > -static int chacha20_stream_xor(struct skcipher_request *req, > - struct chacha20_ctx *ctx, u8 *iv) > +static int chacha_stream_xor(struct skcipher_request *req, > + struct chacha_ctx *ctx, u8 *iv) > { > struct skcipher_walk walk; > u32 state[16]; > @@ -46,7 +46,7 @@ static int chacha20_stream_xor(struct skcipher_request *req, > > err = skcipher_walk_virt(&walk, req, true); > > - crypto_chacha20_init(state, ctx, iv); > + crypto_chacha_init(state, ctx, iv); > > while (walk.nbytes > 0) { > unsigned int nbytes = walk.nbytes; > @@ -54,15 +54,15 @@ static int chacha20_stream_xor(struct skcipher_request *req, > if (nbytes < walk.total) > nbytes = round_down(nbytes, walk.stride); > > - chacha20_docrypt(state, walk.dst.virt.addr, walk.src.virt.addr, > - nbytes); > + chacha_docrypt(state, walk.dst.virt.addr, walk.src.virt.addr, > + nbytes, ctx->nrounds); > err = skcipher_walk_done(&walk, walk.nbytes - nbytes); > } > > return err; > } > > -void crypto_chacha20_init(u32 *state, struct chacha20_ctx *ctx, u8 *iv) > +void crypto_chacha_init(u32 *state, struct chacha_ctx *ctx, u8 *iv) > { > state[0] = 0x61707865; /* "expa" */ > state[1] = 0x3320646e; /* "nd 3" */ > @@ -81,53 +81,61 @@ void crypto_chacha20_init(u32 *state, struct chacha20_ctx *ctx, u8 *iv) > state[14] = get_unaligned_le32(iv + 8); > state[15] = get_unaligned_le32(iv + 12); > } > -EXPORT_SYMBOL_GPL(crypto_chacha20_init); > +EXPORT_SYMBOL_GPL(crypto_chacha_init); > > -int crypto_chacha20_setkey(struct crypto_skcipher *tfm, const u8 *key, > - unsigned int keysize) > +static int chacha_setkey(struct crypto_skcipher *tfm, const u8 *key, > + unsigned int keysize, int nrounds) > { > - struct chacha20_ctx *ctx = crypto_skcipher_ctx(tfm); > + struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm); > int i; > > - if (keysize != CHACHA20_KEY_SIZE) > + if (keysize != CHACHA_KEY_SIZE) > return -EINVAL; > > for (i = 0; i < ARRAY_SIZE(ctx->key); i++) > ctx->key[i] = get_unaligned_le32(key + i * sizeof(u32)); > > + ctx->nrounds = nrounds; > return 0; > } > + > +int crypto_chacha20_setkey(struct crypto_skcipher *tfm, const u8 *key, > + unsigned int keysize) > +{ > + return chacha_setkey(tfm, key, keysize, 20); > +} > EXPORT_SYMBOL_GPL(crypto_chacha20_setkey); > > -int crypto_chacha20_crypt(struct skcipher_request *req) > +int crypto_chacha_crypt(struct skcipher_request *req) > { > struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); > - struct chacha20_ctx *ctx = crypto_skcipher_ctx(tfm); > + struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm); > > - return chacha20_stream_xor(req, ctx, req->iv); > + return chacha_stream_xor(req, ctx, req->iv); > } > -EXPORT_SYMBOL_GPL(crypto_chacha20_crypt); > +EXPORT_SYMBOL_GPL(crypto_chacha_crypt); > > -int crypto_xchacha20_crypt(struct skcipher_request *req) > +int crypto_xchacha_crypt(struct skcipher_request *req) > { > struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); > - struct chacha20_ctx *ctx = crypto_skcipher_ctx(tfm); > - struct chacha20_ctx subctx; > + struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm); > + struct chacha_ctx subctx; > u32 state[16]; > u8 real_iv[16]; > > /* Compute the subkey given the original key and first 128 nonce bits */ > - crypto_chacha20_init(state, ctx, req->iv); > - hchacha20_block(state, subctx.key); > + crypto_chacha_init(state, ctx, req->iv); > + hchacha_block(state, subctx.key, ctx->nrounds); > + subctx.nrounds = ctx->nrounds; > > /* Build the real IV */ > memcpy(&real_iv[0], req->iv + 24, 8); /* stream position */ > memcpy(&real_iv[8], req->iv + 16, 8); /* remaining 64 nonce bits */ > > /* Generate the stream and XOR it with the data */ > - return chacha20_stream_xor(req, &subctx, real_iv); > + return chacha_stream_xor(req, &subctx, real_iv); > } > -EXPORT_SYMBOL_GPL(crypto_xchacha20_crypt); > +EXPORT_SYMBOL_GPL(crypto_xchacha_crypt); > > static struct skcipher_alg algs[] = { > { > @@ -135,50 +143,50 @@ static struct skcipher_alg algs[] = { > .base.cra_driver_name = "chacha20-generic", > .base.cra_priority = 100, > .base.cra_blocksize = 1, > - .base.cra_ctxsize = sizeof(struct chacha20_ctx), > + .base.cra_ctxsize = sizeof(struct chacha_ctx), > .base.cra_module = THIS_MODULE, > > - .min_keysize = CHACHA20_KEY_SIZE, > - .max_keysize = CHACHA20_KEY_SIZE, > - .ivsize = CHACHA20_IV_SIZE, > - .chunksize = CHACHA20_BLOCK_SIZE, > + .min_keysize = CHACHA_KEY_SIZE, > + .max_keysize = CHACHA_KEY_SIZE, > + .ivsize = CHACHA_IV_SIZE, > + .chunksize = CHACHA_BLOCK_SIZE, > .setkey = crypto_chacha20_setkey, > - .encrypt = crypto_chacha20_crypt, > - .decrypt = crypto_chacha20_crypt, > + .encrypt = crypto_chacha_crypt, > + .decrypt = crypto_chacha_crypt, > }, { > .base.cra_name = "xchacha20", > .base.cra_driver_name = "xchacha20-generic", > .base.cra_priority = 100, > .base.cra_blocksize = 1, > - .base.cra_ctxsize = sizeof(struct chacha20_ctx), > + .base.cra_ctxsize = sizeof(struct chacha_ctx), > .base.cra_module = THIS_MODULE, > > - .min_keysize = CHACHA20_KEY_SIZE, > - .max_keysize = CHACHA20_KEY_SIZE, > - .ivsize = XCHACHA20_IV_SIZE, > - .chunksize = CHACHA20_BLOCK_SIZE, > + .min_keysize = CHACHA_KEY_SIZE, > + .max_keysize = CHACHA_KEY_SIZE, > + .ivsize = XCHACHA_IV_SIZE, > + .chunksize = CHACHA_BLOCK_SIZE, > .setkey = crypto_chacha20_setkey, > - .encrypt = crypto_xchacha20_crypt, > - .decrypt = crypto_xchacha20_crypt, > + .encrypt = crypto_xchacha_crypt, > + .decrypt = crypto_xchacha_crypt, > } > }; > > -static int __init chacha20_generic_mod_init(void) > +static int __init chacha_generic_mod_init(void) > { > return crypto_register_skciphers(algs, ARRAY_SIZE(algs)); > } > > -static void __exit chacha20_generic_mod_fini(void) > +static void __exit chacha_generic_mod_fini(void) > { > crypto_unregister_skciphers(algs, ARRAY_SIZE(algs)); > } > > -module_init(chacha20_generic_mod_init); > -module_exit(chacha20_generic_mod_fini); > +module_init(chacha_generic_mod_init); > +module_exit(chacha_generic_mod_fini); > > MODULE_LICENSE("GPL"); > MODULE_AUTHOR("Martin Willi "); > -MODULE_DESCRIPTION("ChaCha20 and XChaCha20 stream ciphers (generic)"); > +MODULE_DESCRIPTION("ChaCha and XChaCha stream ciphers (generic)"); > MODULE_ALIAS_CRYPTO("chacha20"); > MODULE_ALIAS_CRYPTO("chacha20-generic"); > MODULE_ALIAS_CRYPTO("xchacha20"); > diff --git a/drivers/char/random.c b/drivers/char/random.c > index d22d967c50f0a..5f47c4c8b9b15 100644 > --- a/drivers/char/random.c > +++ b/drivers/char/random.c > @@ -265,7 +265,7 @@ > #include > #include > #include > -#include > +#include > > #include > #include > @@ -431,11 +431,10 @@ static int crng_init = 0; > #define crng_ready() (likely(crng_init > 1)) > static int crng_init_cnt = 0; > static unsigned long crng_global_init_time = 0; > -#define CRNG_INIT_CNT_THRESH (2*CHACHA20_KEY_SIZE) > -static void _extract_crng(struct crng_state *crng, > - __u8 out[CHACHA20_BLOCK_SIZE]); > +#define CRNG_INIT_CNT_THRESH (2*CHACHA_KEY_SIZE) > +static void _extract_crng(struct crng_state *crng, __u8 out[CHACHA_BLOCK_SIZE]); > static void _crng_backtrack_protect(struct crng_state *crng, > - __u8 tmp[CHACHA20_BLOCK_SIZE], int used); > + __u8 tmp[CHACHA_BLOCK_SIZE], int used); > static void process_random_ready_list(void); > static void _get_random_bytes(void *buf, int nbytes); > > @@ -858,7 +857,7 @@ static int crng_fast_load(const char *cp, size_t len) > } > p = (unsigned char *) &primary_crng.state[4]; > while (len > 0 && crng_init_cnt < CRNG_INIT_CNT_THRESH) { > - p[crng_init_cnt % CHACHA20_KEY_SIZE] ^= *cp; > + p[crng_init_cnt % CHACHA_KEY_SIZE] ^= *cp; > cp++; crng_init_cnt++; len--; > } > spin_unlock_irqrestore(&primary_crng.lock, flags); > @@ -890,7 +889,7 @@ static int crng_slow_load(const char *cp, size_t len) > unsigned long flags; > static unsigned char lfsr = 1; > unsigned char tmp; > - unsigned i, max = CHACHA20_KEY_SIZE; > + unsigned i, max = CHACHA_KEY_SIZE; > const char * src_buf = cp; > char * dest_buf = (char *) &primary_crng.state[4]; > > @@ -908,8 +907,8 @@ static int crng_slow_load(const char *cp, size_t len) > lfsr >>= 1; > if (tmp & 1) > lfsr ^= 0xE1; > - tmp = dest_buf[i % CHACHA20_KEY_SIZE]; > - dest_buf[i % CHACHA20_KEY_SIZE] ^= src_buf[i % len] ^ lfsr; > + tmp = dest_buf[i % CHACHA_KEY_SIZE]; > + dest_buf[i % CHACHA_KEY_SIZE] ^= src_buf[i % len] ^ lfsr; > lfsr += (tmp << 3) | (tmp >> 5); > } > spin_unlock_irqrestore(&primary_crng.lock, flags); > @@ -921,7 +920,7 @@ static void crng_reseed(struct crng_state *crng, struct entropy_store *r) > unsigned long flags; > int i, num; > union { > - __u8 block[CHACHA20_BLOCK_SIZE]; > + __u8 block[CHACHA_BLOCK_SIZE]; > __u32 key[8]; > } buf; > > @@ -932,7 +931,7 @@ static void crng_reseed(struct crng_state *crng, struct entropy_store *r) > } else { > _extract_crng(&primary_crng, buf.block); > _crng_backtrack_protect(&primary_crng, buf.block, > - CHACHA20_KEY_SIZE); > + CHACHA_KEY_SIZE); > } > spin_lock_irqsave(&crng->lock, flags); > for (i = 0; i < 8; i++) { > @@ -968,7 +967,7 @@ static void crng_reseed(struct crng_state *crng, struct entropy_store *r) > } > > static void _extract_crng(struct crng_state *crng, > - __u8 out[CHACHA20_BLOCK_SIZE]) > + __u8 out[CHACHA_BLOCK_SIZE]) > { > unsigned long v, flags; > > @@ -985,7 +984,7 @@ static void _extract_crng(struct crng_state *crng, > spin_unlock_irqrestore(&crng->lock, flags); > } > > -static void extract_crng(__u8 out[CHACHA20_BLOCK_SIZE]) > +static void extract_crng(__u8 out[CHACHA_BLOCK_SIZE]) > { > struct crng_state *crng = NULL; > > @@ -1003,14 +1002,14 @@ static void extract_crng(__u8 out[CHACHA20_BLOCK_SIZE]) > * enough) to mutate the CRNG key to provide backtracking protection. > */ > static void _crng_backtrack_protect(struct crng_state *crng, > - __u8 tmp[CHACHA20_BLOCK_SIZE], int used) > + __u8 tmp[CHACHA_BLOCK_SIZE], int used) > { > unsigned long flags; > __u32 *s, *d; > int i; > > used = round_up(used, sizeof(__u32)); > - if (used + CHACHA20_KEY_SIZE > CHACHA20_BLOCK_SIZE) { > + if (used + CHACHA_KEY_SIZE > CHACHA_BLOCK_SIZE) { > extract_crng(tmp); > used = 0; > } > @@ -1022,7 +1021,7 @@ static void _crng_backtrack_protect(struct crng_state *crng, > spin_unlock_irqrestore(&crng->lock, flags); > } > > -static void crng_backtrack_protect(__u8 tmp[CHACHA20_BLOCK_SIZE], int used) > +static void crng_backtrack_protect(__u8 tmp[CHACHA_BLOCK_SIZE], int used) > { > struct crng_state *crng = NULL; > > @@ -1037,8 +1036,8 @@ static void crng_backtrack_protect(__u8 tmp[CHACHA20_BLOCK_SIZE], int used) > > static ssize_t extract_crng_user(void __user *buf, size_t nbytes) > { > - ssize_t ret = 0, i = CHACHA20_BLOCK_SIZE; > - __u8 tmp[CHACHA20_BLOCK_SIZE] __aligned(4); > + ssize_t ret = 0, i = CHACHA_BLOCK_SIZE; > + __u8 tmp[CHACHA_BLOCK_SIZE] __aligned(4); > int large_request = (nbytes > 256); > > while (nbytes) { > @@ -1052,7 +1051,7 @@ static ssize_t extract_crng_user(void __user *buf, size_t nbytes) > } > > extract_crng(tmp); > - i = min_t(int, nbytes, CHACHA20_BLOCK_SIZE); > + i = min_t(int, nbytes, CHACHA_BLOCK_SIZE); > if (copy_to_user(buf, tmp, i)) { > ret = -EFAULT; > break; > @@ -1617,14 +1616,14 @@ static void _warn_unseeded_randomness(const char *func_name, void *caller, > */ > static void _get_random_bytes(void *buf, int nbytes) > { > - __u8 tmp[CHACHA20_BLOCK_SIZE] __aligned(4); > + __u8 tmp[CHACHA_BLOCK_SIZE] __aligned(4); > > trace_get_random_bytes(nbytes, _RET_IP_); > > - while (nbytes >= CHACHA20_BLOCK_SIZE) { > + while (nbytes >= CHACHA_BLOCK_SIZE) { > extract_crng(buf); > - buf += CHACHA20_BLOCK_SIZE; > - nbytes -= CHACHA20_BLOCK_SIZE; > + buf += CHACHA_BLOCK_SIZE; > + nbytes -= CHACHA_BLOCK_SIZE; > } > > if (nbytes > 0) { > @@ -1632,7 +1631,7 @@ static void _get_random_bytes(void *buf, int nbytes) > memcpy(buf, tmp, nbytes); > crng_backtrack_protect(tmp, nbytes); > } else > - crng_backtrack_protect(tmp, CHACHA20_BLOCK_SIZE); > + crng_backtrack_protect(tmp, CHACHA_BLOCK_SIZE); > memzero_explicit(tmp, sizeof(tmp)); > } > > @@ -2203,8 +2202,8 @@ struct ctl_table random_table[] = { > > struct batched_entropy { > union { > - u64 entropy_u64[CHACHA20_BLOCK_SIZE / sizeof(u64)]; > - u32 entropy_u32[CHACHA20_BLOCK_SIZE / sizeof(u32)]; > + u64 entropy_u64[CHACHA_BLOCK_SIZE / sizeof(u64)]; > + u32 entropy_u32[CHACHA_BLOCK_SIZE / sizeof(u32)]; > }; > unsigned int position; > }; > diff --git a/include/crypto/chacha.h b/include/crypto/chacha.h > new file mode 100644 > index 0000000000000..ae79e9983c72f > --- /dev/null > +++ b/include/crypto/chacha.h > @@ -0,0 +1,46 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * Common values and helper functions for the ChaCha and XChaCha stream ciphers. > + * > + * XChaCha extends ChaCha's nonce to 192 bits, while provably retaining ChaCha's > + * security. Here they share the same key size, tfm context, and setkey > + * function; only their IV size and encrypt/decrypt function differ. > + */ > + > +#ifndef _CRYPTO_CHACHA_H > +#define _CRYPTO_CHACHA_H > + > +#include > +#include > +#include > + > +/* 32-bit stream position, then 96-bit nonce (RFC7539 convention) */ > +#define CHACHA_IV_SIZE 16 > + > +#define CHACHA_KEY_SIZE 32 > +#define CHACHA_BLOCK_SIZE 64 > + > +/* 192-bit nonce, then 64-bit stream position */ > +#define XCHACHA_IV_SIZE 32 > + > +struct chacha_ctx { > + u32 key[8]; > + int nrounds; > +}; > + > +void chacha_block(u32 *state, u8 *stream, int nrounds); > +static inline void chacha20_block(u32 *state, u8 *stream) > +{ > + chacha_block(state, stream, 20); > +} > +void hchacha_block(const u32 *in, u32 *out, int nrounds); > + > +void crypto_chacha_init(u32 *state, struct chacha_ctx *ctx, u8 *iv); > + > +int crypto_chacha20_setkey(struct crypto_skcipher *tfm, const u8 *key, > + unsigned int keysize); > + > +int crypto_chacha_crypt(struct skcipher_request *req); > +int crypto_xchacha_crypt(struct skcipher_request *req); > + > +#endif /* _CRYPTO_CHACHA_H */ > diff --git a/include/crypto/chacha20.h b/include/crypto/chacha20.h > deleted file mode 100644 > index 6290d997060ec..0000000000000 > --- a/include/crypto/chacha20.h > +++ /dev/null > @@ -1,41 +0,0 @@ > -/* SPDX-License-Identifier: GPL-2.0 */ > -/* > - * Common values and helper functions for the ChaCha20 and XChaCha20 algorithms. > - * > - * XChaCha20 extends ChaCha20's nonce to 192 bits, while provably retaining > - * ChaCha20's security. Here they share the same key size, tfm context, and > - * setkey function; only their IV size and encrypt/decrypt function differ. > - */ > - > -#ifndef _CRYPTO_CHACHA20_H > -#define _CRYPTO_CHACHA20_H > - > -#include > -#include > -#include > - > -/* 32-bit stream position, then 96-bit nonce (RFC7539 convention) */ > -#define CHACHA20_IV_SIZE 16 > - > -#define CHACHA20_KEY_SIZE 32 > -#define CHACHA20_BLOCK_SIZE 64 > - > -/* 192-bit nonce, then 64-bit stream position */ > -#define XCHACHA20_IV_SIZE 32 > - > -struct chacha20_ctx { > - u32 key[8]; > -}; > - > -void chacha20_block(u32 *state, u8 *stream); > -void hchacha20_block(const u32 *in, u32 *out); > - > -void crypto_chacha20_init(u32 *state, struct chacha20_ctx *ctx, u8 *iv); > - > -int crypto_chacha20_setkey(struct crypto_skcipher *tfm, const u8 *key, > - unsigned int keysize); > - > -int crypto_chacha20_crypt(struct skcipher_request *req); > -int crypto_xchacha20_crypt(struct skcipher_request *req); > - > -#endif > diff --git a/lib/Makefile b/lib/Makefile > index ca3f7ebb900d8..9a5f0b7a48891 100644 > --- a/lib/Makefile > +++ b/lib/Makefile > @@ -20,7 +20,7 @@ KCOV_INSTRUMENT_dynamic_debug.o := n > lib-y := ctype.o string.o vsprintf.o cmdline.o \ > rbtree.o radix-tree.o timerqueue.o\ > idr.o int_sqrt.o extable.o \ > - sha1.o chacha20.o irq_regs.o argv_split.o \ > + sha1.o chacha.o irq_regs.o argv_split.o \ > flex_proportions.o ratelimit.o show_mem.o \ > is_single_threaded.o plist.o decompress.o kobject_uevent.o \ > earlycpio.o seq_buf.o siphash.o dec_and_lock.o \ > diff --git a/lib/chacha20.c b/lib/chacha.c > similarity index 67% > rename from lib/chacha20.c > rename to lib/chacha.c > index 6a484e16171d1..0a2c2e5b7b84d 100644 > --- a/lib/chacha20.c > +++ b/lib/chacha.c > @@ -1,5 +1,5 @@ > /* > - * The "hash function" used as the core of the ChaCha20 stream cipher (RFC7539) > + * The "hash function" used as the core of the ChaCha stream cipher (RFC7539) > * > * Copyright (C) 2015 Martin Willi > * > @@ -14,13 +14,16 @@ > #include > #include > #include > -#include > +#include > > -static void chacha20_permute(u32 *x) > +static void chacha_permute(u32 *x, int nrounds) > { > int i; > > - for (i = 0; i < 20; i += 2) { > + /* whitelist the allowed round counts */ > + BUG_ON(nrounds != 20); > + > + for (i = 0; i < nrounds; i += 2) { > x[0] += x[4]; x[12] = rol32(x[12] ^ x[0], 16); > x[1] += x[5]; x[13] = rol32(x[13] ^ x[1], 16); > x[2] += x[6]; x[14] = rol32(x[14] ^ x[2], 16); > @@ -64,49 +67,51 @@ static void chacha20_permute(u32 *x) > } > > /** > - * chacha20_block - generate one keystream block and increment block counter > + * chacha_block - generate one keystream block and increment block counter > * @state: input state matrix (16 32-bit words) > * @stream: output keystream block (64 bytes) > + * @nrounds: number of rounds (currently must be 20) > * > - * This is the ChaCha20 core, a function from 64-byte strings to 64-byte > - * strings. The caller has already converted the endianness of the input. This > - * function also handles incrementing the block counter in the input matrix. > + * This is the ChaCha core, a function from 64-byte strings to 64-byte strings. > + * The caller has already converted the endianness of the input. This function > + * also handles incrementing the block counter in the input matrix. > */ > -void chacha20_block(u32 *state, u8 *stream) > +void chacha_block(u32 *state, u8 *stream, int nrounds) > { > u32 x[16]; > int i; > > memcpy(x, state, 64); > > - chacha20_permute(x); > + chacha_permute(x, nrounds); > > for (i = 0; i < ARRAY_SIZE(x); i++) > put_unaligned_le32(x[i] + state[i], &stream[i * sizeof(u32)]); > > state[12]++; > } > -EXPORT_SYMBOL(chacha20_block); > +EXPORT_SYMBOL(chacha_block); > > /** > - * hchacha20_block - abbreviated ChaCha20 core, for XChaCha20 > + * hchacha_block - abbreviated ChaCha core, for XChaCha > * @in: input state matrix (16 32-bit words) > * @out: output (8 32-bit words) > + * @nrounds: number of rounds (currently must be 20) > * > - * HChaCha20 is the ChaCha equivalent of HSalsa20 and is an intermediate step > - * towards XChaCha20 (see https://cr.yp.to/snuffle/xsalsa-20081128.pdf). > - * HChaCha20 skips the final addition of the initial state, and outputs only > - * certain words of the state. It should not be used for streaming directly. > + * HChaCha is the ChaCha equivalent of HSalsa and is an intermediate step > + * towards XChaCha (see https://cr.yp.to/snuffle/xsalsa-20081128.pdf). HChaCha > + * skips the final addition of the initial state, and outputs only certain words > + * of the state. It should not be used for streaming directly. > */ > -void hchacha20_block(const u32 *in, u32 *out) > +void hchacha_block(const u32 *in, u32 *out, int nrounds) > { > u32 x[16]; > > memcpy(x, in, 64); > > - chacha20_permute(x); > + chacha_permute(x, nrounds); > > memcpy(&out[0], &x[0], 16); > memcpy(&out[4], &x[12], 16); > } > -EXPORT_SYMBOL(hchacha20_block); > +EXPORT_SYMBOL(hchacha_block); > -- > 2.19.1.331.ge82ca0e54c-goog >