From: Eric Biggers <ebiggers@xxxxxxxxxx> In preparation for adding XChaCha12 support, rename/refactor chacha20-generic to support different numbers of rounds. 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 reduced-round ChaCha is introduced by this patch. Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx> --- arch/arm/crypto/chacha20-neon-glue.c | 44 +++---- 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 | 50 ++++---- include/crypto/chacha.h | 47 ++++++++ include/crypto/chacha20.h | 42 ------- lib/Makefile | 2 +- lib/{chacha20.c => chacha.c} | 43 ++++--- 11 files changed, 230 insertions(+), 212 deletions(-) rename crypto/{chacha20_generic.c => chacha_generic.c} (56%) 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 59a7be08e80c..ed8dec0f1768 100644 --- a/arch/arm/crypto/chacha20-neon-glue.c +++ b/arch/arm/crypto/chacha20-neon-glue.c @@ -19,7 +19,7 @@ */ #include <crypto/algapi.h> -#include <crypto/chacha20.h> +#include <crypto/chacha.h> #include <crypto/internal/skcipher.h> #include <linux/kernel.h> #include <linux/module.h> @@ -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) { @@ -93,17 +93,17 @@ 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, + .encrypt = chacha_neon, + .decrypt = chacha_neon, }; static int __init chacha20_simd_mod_init(void) diff --git a/arch/arm64/crypto/chacha20-neon-glue.c b/arch/arm64/crypto/chacha20-neon-glue.c index 727579c93ded..96e0cfb8c3f5 100644 --- a/arch/arm64/crypto/chacha20-neon-glue.c +++ b/arch/arm64/crypto/chacha20-neon-glue.c @@ -19,7 +19,7 @@ */ #include <crypto/algapi.h> -#include <crypto/chacha20.h> +#include <crypto/chacha.h> #include <crypto/internal/skcipher.h> #include <linux/kernel.h> #include <linux/module.h> @@ -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 dce7c5d39c2f..bd249f0b29dc 100644 --- a/arch/x86/crypto/chacha20_glue.c +++ b/arch/x86/crypto/chacha20_glue.c @@ -10,7 +10,7 @@ */ #include <crypto/algapi.h> -#include <crypto/chacha20.h> +#include <crypto/chacha.h> #include <crypto/internal/skcipher.h> #include <linux/kernel.h> #include <linux/module.h> @@ -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 6d1d40eeb964..0701c4577dc6 100644 --- a/crypto/Makefile +++ b/crypto/Makefile @@ -117,7 +117,7 @@ obj-$(CONFIG_CRYPTO_ANUBIS) += anubis.o obj-$(CONFIG_CRYPTO_SEED) += seed.o obj-$(CONFIG_CRYPTO_SPECK) += speck.o obj-$(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 600afa99941f..573c07e6f189 100644 --- a/crypto/chacha20poly1305.c +++ b/crypto/chacha20poly1305.c @@ -13,7 +13,7 @@ #include <crypto/internal/hash.h> #include <crypto/internal/skcipher.h> #include <crypto/scatterwalk.h> -#include <crypto/chacha20.h> +#include <crypto/chacha.h> #include <crypto/poly1305.h> #include <linux/err.h> #include <linux/init.h> @@ -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 56% rename from crypto/chacha20_generic.c rename to crypto/chacha_generic.c index ba97aac93912..46496997847a 100644 --- a/crypto/chacha20_generic.c +++ b/crypto/chacha_generic.c @@ -12,32 +12,32 @@ #include <asm/unaligned.h> #include <crypto/algapi.h> -#include <crypto/chacha20.h> +#include <crypto/chacha.h> #include <crypto/internal/skcipher.h> #include <linux/module.h> -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) { - u32 stream[CHACHA20_BLOCK_WORDS]; + u32 stream[CHACHA_BLOCK_WORDS]; if (dst != src) memcpy(dst, src, bytes); - while (bytes >= CHACHA20_BLOCK_SIZE) { - chacha20_block(state, stream); - crypto_xor(dst, (const u8 *)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, (const u8 *)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, (const u8 *)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]; @@ -45,7 +45,7 @@ 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; @@ -53,15 +53,15 @@ 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" */ @@ -80,53 +80,61 @@ 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[] = { { @@ -134,50 +142,50 @@ 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 <martin@xxxxxxxxxxxxxx>"); -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 bd449ad52442..edf956084179 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -265,7 +265,7 @@ #include <linux/syscalls.h> #include <linux/completion.h> #include <linux/uuid.h> -#include <crypto/chacha20.h> +#include <crypto/chacha.h> #include <asm/processor.h> #include <linux/uaccess.h> @@ -431,11 +431,11 @@ 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) +#define CRNG_INIT_CNT_THRESH (2*CHACHA_KEY_SIZE) static void _extract_crng(struct crng_state *crng, - __u32 out[CHACHA20_BLOCK_WORDS]); + __u32 out[CHACHA_BLOCK_WORDS]); static void _crng_backtrack_protect(struct crng_state *crng, - __u32 tmp[CHACHA20_BLOCK_WORDS], int used); + __u32 tmp[CHACHA_BLOCK_WORDS], int used); static void process_random_ready_list(void); static void _get_random_bytes(void *buf, int nbytes); @@ -849,7 +849,7 @@ 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); @@ -881,7 +881,7 @@ 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]; @@ -899,8 +899,8 @@ 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); @@ -912,7 +912,7 @@ static void crng_reseed(struct crng_state *crng, struct entropy_store *r) unsigned long flags; int i, num; union { - __u32 block[CHACHA20_BLOCK_WORDS]; + __u32 block[CHACHA_BLOCK_WORDS]; __u32 key[8]; } buf; @@ -923,7 +923,7 @@ 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++) { @@ -959,7 +959,7 @@ static void crng_reseed(struct crng_state *crng, struct entropy_store *r) } static void _extract_crng(struct crng_state *crng, - __u32 out[CHACHA20_BLOCK_WORDS]) + __u32 out[CHACHA_BLOCK_WORDS]) { unsigned long v, flags; @@ -976,7 +976,7 @@ static void _extract_crng(struct crng_state *crng, spin_unlock_irqrestore(&crng->lock, flags); } -static void extract_crng(__u32 out[CHACHA20_BLOCK_WORDS]) +static void extract_crng(__u32 out[CHACHA_BLOCK_WORDS]) { struct crng_state *crng = NULL; @@ -994,14 +994,14 @@ static void extract_crng(__u32 out[CHACHA20_BLOCK_WORDS]) * enough) to mutate the CRNG key to provide backtracking protection. */ static void _crng_backtrack_protect(struct crng_state *crng, - __u32 tmp[CHACHA20_BLOCK_WORDS], int used) + __u32 tmp[CHACHA_BLOCK_WORDS], 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; } @@ -1013,7 +1013,7 @@ static void _crng_backtrack_protect(struct crng_state *crng, spin_unlock_irqrestore(&crng->lock, flags); } -static void crng_backtrack_protect(__u32 tmp[CHACHA20_BLOCK_WORDS], int used) +static void crng_backtrack_protect(__u32 tmp[CHACHA_BLOCK_WORDS], int used) { struct crng_state *crng = NULL; @@ -1028,8 +1028,8 @@ static void crng_backtrack_protect(__u32 tmp[CHACHA20_BLOCK_WORDS], int used) static ssize_t extract_crng_user(void __user *buf, size_t nbytes) { - ssize_t ret = 0, i = CHACHA20_BLOCK_SIZE; - __u32 tmp[CHACHA20_BLOCK_WORDS]; + ssize_t ret = 0, i = CHACHA_BLOCK_SIZE; + __u32 tmp[CHACHA_BLOCK_WORDS]; int large_request = (nbytes > 256); while (nbytes) { @@ -1043,7 +1043,7 @@ 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; @@ -1612,14 +1612,14 @@ static void _warn_unseeded_randomness(const char *func_name, void *caller, */ static void _get_random_bytes(void *buf, int nbytes) { - __u32 tmp[CHACHA20_BLOCK_WORDS]; + __u32 tmp[CHACHA_BLOCK_WORDS]; 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) { @@ -1627,7 +1627,7 @@ 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)); } @@ -2182,8 +2182,8 @@ 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 000000000000..a504350f54df --- /dev/null +++ b/include/crypto/chacha.h @@ -0,0 +1,47 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Common values and helper functions for the ChaCha and XChaCha algorithms. + * + * 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 <crypto/skcipher.h> +#include <linux/types.h> +#include <linux/crypto.h> + +/* 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 +#define CHACHA_BLOCK_WORDS (CHACHA_BLOCK_SIZE / sizeof(u32)) + +/* 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, u32 *stream, int nrounds); +static inline void chacha20_block(u32 *state, u32 *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 f977e685925d..000000000000 --- a/include/crypto/chacha20.h +++ /dev/null @@ -1,42 +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 <crypto/skcipher.h> -#include <linux/types.h> -#include <linux/crypto.h> - -/* 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 -#define CHACHA20_BLOCK_WORDS (CHACHA20_BLOCK_SIZE / sizeof(u32)) - -/* 192-bit nonce, then 64-bit stream position */ -#define XCHACHA20_IV_SIZE 32 - -struct chacha20_ctx { - u32 key[8]; -}; - -void chacha20_block(u32 *state, u32 *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 90dc5520b784..e37f0f922185 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 13a0bdcb1604..b0fd1e0882e3 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 <linux/bitops.h> #include <linux/cryptohash.h> #include <asm/unaligned.h> -#include <crypto/chacha20.h> +#include <crypto/chacha.h> -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, u32 *stream) +void chacha_block(u32 *state, u32 *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++) stream[i] = cpu_to_le32(x[i] + state[i]); 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); -- 2.18.0.597.ga71716f1ad-goog