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-rw-r--r--arch/x86/crypto/chacha_glue.c304
1 files changed, 304 insertions, 0 deletions
diff --git a/arch/x86/crypto/chacha_glue.c b/arch/x86/crypto/chacha_glue.c
new file mode 100644
index 000000000000..45c1c4143176
--- /dev/null
+++ b/arch/x86/crypto/chacha_glue.c
@@ -0,0 +1,304 @@
+/*
+ * x64 SIMD accelerated ChaCha and XChaCha stream ciphers,
+ * including ChaCha20 (RFC7539)
+ *
+ * Copyright (C) 2015 Martin Willi
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <crypto/algapi.h>
+#include <crypto/chacha.h>
+#include <crypto/internal/skcipher.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <asm/fpu/api.h>
+#include <asm/simd.h>
+
+#define CHACHA_STATE_ALIGN 16
+
+asmlinkage void chacha_block_xor_ssse3(u32 *state, u8 *dst, const u8 *src,
+ unsigned int len, int nrounds);
+asmlinkage void chacha_4block_xor_ssse3(u32 *state, u8 *dst, const u8 *src,
+ unsigned int len, int nrounds);
+asmlinkage void hchacha_block_ssse3(const u32 *state, u32 *out, int nrounds);
+#ifdef CONFIG_AS_AVX2
+asmlinkage void chacha_2block_xor_avx2(u32 *state, u8 *dst, const u8 *src,
+ unsigned int len, int nrounds);
+asmlinkage void chacha_4block_xor_avx2(u32 *state, u8 *dst, const u8 *src,
+ unsigned int len, int nrounds);
+asmlinkage void chacha_8block_xor_avx2(u32 *state, u8 *dst, const u8 *src,
+ unsigned int len, int nrounds);
+static bool chacha_use_avx2;
+#ifdef CONFIG_AS_AVX512
+asmlinkage void chacha_2block_xor_avx512vl(u32 *state, u8 *dst, const u8 *src,
+ unsigned int len, int nrounds);
+asmlinkage void chacha_4block_xor_avx512vl(u32 *state, u8 *dst, const u8 *src,
+ unsigned int len, int nrounds);
+asmlinkage void chacha_8block_xor_avx512vl(u32 *state, u8 *dst, const u8 *src,
+ unsigned int len, int nrounds);
+static bool chacha_use_avx512vl;
+#endif
+#endif
+
+static unsigned int chacha_advance(unsigned int len, unsigned int maxblocks)
+{
+ len = min(len, maxblocks * CHACHA_BLOCK_SIZE);
+ return round_up(len, CHACHA_BLOCK_SIZE) / CHACHA_BLOCK_SIZE;
+}
+
+static void chacha_dosimd(u32 *state, u8 *dst, const u8 *src,
+ unsigned int bytes, int nrounds)
+{
+#ifdef CONFIG_AS_AVX2
+#ifdef CONFIG_AS_AVX512
+ if (chacha_use_avx512vl) {
+ while (bytes >= CHACHA_BLOCK_SIZE * 8) {
+ chacha_8block_xor_avx512vl(state, dst, src, bytes,
+ nrounds);
+ bytes -= CHACHA_BLOCK_SIZE * 8;
+ src += CHACHA_BLOCK_SIZE * 8;
+ dst += CHACHA_BLOCK_SIZE * 8;
+ state[12] += 8;
+ }
+ if (bytes > CHACHA_BLOCK_SIZE * 4) {
+ chacha_8block_xor_avx512vl(state, dst, src, bytes,
+ nrounds);
+ state[12] += chacha_advance(bytes, 8);
+ return;
+ }
+ if (bytes > CHACHA_BLOCK_SIZE * 2) {
+ chacha_4block_xor_avx512vl(state, dst, src, bytes,
+ nrounds);
+ state[12] += chacha_advance(bytes, 4);
+ return;
+ }
+ if (bytes) {
+ chacha_2block_xor_avx512vl(state, dst, src, bytes,
+ nrounds);
+ state[12] += chacha_advance(bytes, 2);
+ return;
+ }
+ }
+#endif
+ if (chacha_use_avx2) {
+ while (bytes >= CHACHA_BLOCK_SIZE * 8) {
+ chacha_8block_xor_avx2(state, dst, src, bytes, nrounds);
+ bytes -= CHACHA_BLOCK_SIZE * 8;
+ src += CHACHA_BLOCK_SIZE * 8;
+ dst += CHACHA_BLOCK_SIZE * 8;
+ state[12] += 8;
+ }
+ if (bytes > CHACHA_BLOCK_SIZE * 4) {
+ chacha_8block_xor_avx2(state, dst, src, bytes, nrounds);
+ state[12] += chacha_advance(bytes, 8);
+ return;
+ }
+ if (bytes > CHACHA_BLOCK_SIZE * 2) {
+ chacha_4block_xor_avx2(state, dst, src, bytes, nrounds);
+ state[12] += chacha_advance(bytes, 4);
+ return;
+ }
+ if (bytes > CHACHA_BLOCK_SIZE) {
+ chacha_2block_xor_avx2(state, dst, src, bytes, nrounds);
+ state[12] += chacha_advance(bytes, 2);
+ return;
+ }
+ }
+#endif
+ while (bytes >= CHACHA_BLOCK_SIZE * 4) {
+ chacha_4block_xor_ssse3(state, dst, src, bytes, nrounds);
+ bytes -= CHACHA_BLOCK_SIZE * 4;
+ src += CHACHA_BLOCK_SIZE * 4;
+ dst += CHACHA_BLOCK_SIZE * 4;
+ state[12] += 4;
+ }
+ if (bytes > CHACHA_BLOCK_SIZE) {
+ chacha_4block_xor_ssse3(state, dst, src, bytes, nrounds);
+ state[12] += chacha_advance(bytes, 4);
+ return;
+ }
+ if (bytes) {
+ chacha_block_xor_ssse3(state, dst, src, bytes, nrounds);
+ state[12]++;
+ }
+}
+
+static int chacha_simd_stream_xor(struct skcipher_walk *walk,
+ struct chacha_ctx *ctx, u8 *iv)
+{
+ u32 *state, state_buf[16 + 2] __aligned(8);
+ int next_yield = 4096; /* bytes until next FPU yield */
+ int err = 0;
+
+ BUILD_BUG_ON(CHACHA_STATE_ALIGN != 16);
+ state = PTR_ALIGN(state_buf + 0, CHACHA_STATE_ALIGN);
+
+ crypto_chacha_init(state, ctx, iv);
+
+ while (walk->nbytes > 0) {
+ unsigned int nbytes = walk->nbytes;
+
+ if (nbytes < walk->total) {
+ nbytes = round_down(nbytes, walk->stride);
+ next_yield -= nbytes;
+ }
+
+ chacha_dosimd(state, walk->dst.virt.addr, walk->src.virt.addr,
+ nbytes, ctx->nrounds);
+
+ if (next_yield <= 0) {
+ /* temporarily allow preemption */
+ kernel_fpu_end();
+ kernel_fpu_begin();
+ next_yield = 4096;
+ }
+
+ err = skcipher_walk_done(walk, walk->nbytes - nbytes);
+ }
+
+ return err;
+}
+
+static int chacha_simd(struct skcipher_request *req)
+{
+ struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+ struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm);
+ struct skcipher_walk walk;
+ int err;
+
+ if (req->cryptlen <= CHACHA_BLOCK_SIZE || !irq_fpu_usable())
+ return crypto_chacha_crypt(req);
+
+ err = skcipher_walk_virt(&walk, req, true);
+ if (err)
+ return err;
+
+ kernel_fpu_begin();
+ err = chacha_simd_stream_xor(&walk, ctx, req->iv);
+ kernel_fpu_end();
+ return err;
+}
+
+static int xchacha_simd(struct skcipher_request *req)
+{
+ struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+ struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm);
+ struct skcipher_walk walk;
+ struct chacha_ctx subctx;
+ u32 *state, state_buf[16 + 2] __aligned(8);
+ u8 real_iv[16];
+ int err;
+
+ if (req->cryptlen <= CHACHA_BLOCK_SIZE || !irq_fpu_usable())
+ return crypto_xchacha_crypt(req);
+
+ err = skcipher_walk_virt(&walk, req, true);
+ if (err)
+ return err;
+
+ BUILD_BUG_ON(CHACHA_STATE_ALIGN != 16);
+ state = PTR_ALIGN(state_buf + 0, CHACHA_STATE_ALIGN);
+ crypto_chacha_init(state, ctx, req->iv);
+
+ kernel_fpu_begin();
+
+ hchacha_block_ssse3(state, subctx.key, ctx->nrounds);
+ subctx.nrounds = ctx->nrounds;
+
+ memcpy(&real_iv[0], req->iv + 24, 8);
+ memcpy(&real_iv[8], req->iv + 16, 8);
+ err = chacha_simd_stream_xor(&walk, &subctx, real_iv);
+
+ kernel_fpu_end();
+
+ return err;
+}
+
+static struct skcipher_alg algs[] = {
+ {
+ .base.cra_name = "chacha20",
+ .base.cra_driver_name = "chacha20-simd",
+ .base.cra_priority = 300,
+ .base.cra_blocksize = 1,
+ .base.cra_ctxsize = sizeof(struct chacha_ctx),
+ .base.cra_module = THIS_MODULE,
+
+ .min_keysize = CHACHA_KEY_SIZE,
+ .max_keysize = CHACHA_KEY_SIZE,
+ .ivsize = CHACHA_IV_SIZE,
+ .chunksize = CHACHA_BLOCK_SIZE,
+ .setkey = crypto_chacha20_setkey,
+ .encrypt = chacha_simd,
+ .decrypt = chacha_simd,
+ }, {
+ .base.cra_name = "xchacha20",
+ .base.cra_driver_name = "xchacha20-simd",
+ .base.cra_priority = 300,
+ .base.cra_blocksize = 1,
+ .base.cra_ctxsize = sizeof(struct chacha_ctx),
+ .base.cra_module = THIS_MODULE,
+
+ .min_keysize = CHACHA_KEY_SIZE,
+ .max_keysize = CHACHA_KEY_SIZE,
+ .ivsize = XCHACHA_IV_SIZE,
+ .chunksize = CHACHA_BLOCK_SIZE,
+ .setkey = crypto_chacha20_setkey,
+ .encrypt = xchacha_simd,
+ .decrypt = xchacha_simd,
+ }, {
+ .base.cra_name = "xchacha12",
+ .base.cra_driver_name = "xchacha12-simd",
+ .base.cra_priority = 300,
+ .base.cra_blocksize = 1,
+ .base.cra_ctxsize = sizeof(struct chacha_ctx),
+ .base.cra_module = THIS_MODULE,
+
+ .min_keysize = CHACHA_KEY_SIZE,
+ .max_keysize = CHACHA_KEY_SIZE,
+ .ivsize = XCHACHA_IV_SIZE,
+ .chunksize = CHACHA_BLOCK_SIZE,
+ .setkey = crypto_chacha12_setkey,
+ .encrypt = xchacha_simd,
+ .decrypt = xchacha_simd,
+ },
+};
+
+static int __init chacha_simd_mod_init(void)
+{
+ if (!boot_cpu_has(X86_FEATURE_SSSE3))
+ return -ENODEV;
+
+#ifdef CONFIG_AS_AVX2
+ chacha_use_avx2 = boot_cpu_has(X86_FEATURE_AVX) &&
+ boot_cpu_has(X86_FEATURE_AVX2) &&
+ cpu_has_xfeatures(XFEATURE_MASK_SSE | XFEATURE_MASK_YMM, NULL);
+#ifdef CONFIG_AS_AVX512
+ chacha_use_avx512vl = chacha_use_avx2 &&
+ boot_cpu_has(X86_FEATURE_AVX512VL) &&
+ boot_cpu_has(X86_FEATURE_AVX512BW); /* kmovq */
+#endif
+#endif
+ return crypto_register_skciphers(algs, ARRAY_SIZE(algs));
+}
+
+static void __exit chacha_simd_mod_fini(void)
+{
+ crypto_unregister_skciphers(algs, ARRAY_SIZE(algs));
+}
+
+module_init(chacha_simd_mod_init);
+module_exit(chacha_simd_mod_fini);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Martin Willi <martin@strongswan.org>");
+MODULE_DESCRIPTION("ChaCha and XChaCha stream ciphers (x64 SIMD accelerated)");
+MODULE_ALIAS_CRYPTO("chacha20");
+MODULE_ALIAS_CRYPTO("chacha20-simd");
+MODULE_ALIAS_CRYPTO("xchacha20");
+MODULE_ALIAS_CRYPTO("xchacha20-simd");
+MODULE_ALIAS_CRYPTO("xchacha12");
+MODULE_ALIAS_CRYPTO("xchacha12-simd");
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.