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-rw-r--r--arch/arm/crypto/speck-neon-glue.c288
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diff --git a/arch/arm/crypto/speck-neon-glue.c b/arch/arm/crypto/speck-neon-glue.c
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+++ b/arch/arm/crypto/speck-neon-glue.c
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+// SPDX-License-Identifier: GPL-2.0
+/*
+ * NEON-accelerated implementation of Speck128-XTS and Speck64-XTS
+ *
+ * Copyright (c) 2018 Google, Inc
+ *
+ * Note: the NIST recommendation for XTS only specifies a 128-bit block size,
+ * but a 64-bit version (needed for Speck64) is fairly straightforward; the math
+ * is just done in GF(2^64) instead of GF(2^128), with the reducing polynomial
+ * x^64 + x^4 + x^3 + x + 1 from the original XEX paper (Rogaway, 2004:
+ * "Efficient Instantiations of Tweakable Blockciphers and Refinements to Modes
+ * OCB and PMAC"), represented as 0x1B.
+ */
+
+#include <asm/hwcap.h>
+#include <asm/neon.h>
+#include <asm/simd.h>
+#include <crypto/algapi.h>
+#include <crypto/gf128mul.h>
+#include <crypto/internal/skcipher.h>
+#include <crypto/speck.h>
+#include <crypto/xts.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+/* The assembly functions only handle multiples of 128 bytes */
+#define SPECK_NEON_CHUNK_SIZE 128
+
+/* Speck128 */
+
+struct speck128_xts_tfm_ctx {
+ struct speck128_tfm_ctx main_key;
+ struct speck128_tfm_ctx tweak_key;
+};
+
+asmlinkage void speck128_xts_encrypt_neon(const u64 *round_keys, int nrounds,
+ void *dst, const void *src,
+ unsigned int nbytes, void *tweak);
+
+asmlinkage void speck128_xts_decrypt_neon(const u64 *round_keys, int nrounds,
+ void *dst, const void *src,
+ unsigned int nbytes, void *tweak);
+
+typedef void (*speck128_crypt_one_t)(const struct speck128_tfm_ctx *,
+ u8 *, const u8 *);
+typedef void (*speck128_xts_crypt_many_t)(const u64 *, int, void *,
+ const void *, unsigned int, void *);
+
+static __always_inline int
+__speck128_xts_crypt(struct skcipher_request *req,
+ speck128_crypt_one_t crypt_one,
+ speck128_xts_crypt_many_t crypt_many)
+{
+ struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+ const struct speck128_xts_tfm_ctx *ctx = crypto_skcipher_ctx(tfm);
+ struct skcipher_walk walk;
+ le128 tweak;
+ int err;
+
+ err = skcipher_walk_virt(&walk, req, true);
+
+ crypto_speck128_encrypt(&ctx->tweak_key, (u8 *)&tweak, walk.iv);
+
+ while (walk.nbytes > 0) {
+ unsigned int nbytes = walk.nbytes;
+ u8 *dst = walk.dst.virt.addr;
+ const u8 *src = walk.src.virt.addr;
+
+ if (nbytes >= SPECK_NEON_CHUNK_SIZE && may_use_simd()) {
+ unsigned int count;
+
+ count = round_down(nbytes, SPECK_NEON_CHUNK_SIZE);
+ kernel_neon_begin();
+ (*crypt_many)(ctx->main_key.round_keys,
+ ctx->main_key.nrounds,
+ dst, src, count, &tweak);
+ kernel_neon_end();
+ dst += count;
+ src += count;
+ nbytes -= count;
+ }
+
+ /* Handle any remainder with generic code */
+ while (nbytes >= sizeof(tweak)) {
+ le128_xor((le128 *)dst, (const le128 *)src, &tweak);
+ (*crypt_one)(&ctx->main_key, dst, dst);
+ le128_xor((le128 *)dst, (const le128 *)dst, &tweak);
+ gf128mul_x_ble(&tweak, &tweak);
+
+ dst += sizeof(tweak);
+ src += sizeof(tweak);
+ nbytes -= sizeof(tweak);
+ }
+ err = skcipher_walk_done(&walk, nbytes);
+ }
+
+ return err;
+}
+
+static int speck128_xts_encrypt(struct skcipher_request *req)
+{
+ return __speck128_xts_crypt(req, crypto_speck128_encrypt,
+ speck128_xts_encrypt_neon);
+}
+
+static int speck128_xts_decrypt(struct skcipher_request *req)
+{
+ return __speck128_xts_crypt(req, crypto_speck128_decrypt,
+ speck128_xts_decrypt_neon);
+}
+
+static int speck128_xts_setkey(struct crypto_skcipher *tfm, const u8 *key,
+ unsigned int keylen)
+{
+ struct speck128_xts_tfm_ctx *ctx = crypto_skcipher_ctx(tfm);
+ int err;
+
+ err = xts_verify_key(tfm, key, keylen);
+ if (err)
+ return err;
+
+ keylen /= 2;
+
+ err = crypto_speck128_setkey(&ctx->main_key, key, keylen);
+ if (err)
+ return err;
+
+ return crypto_speck128_setkey(&ctx->tweak_key, key + keylen, keylen);
+}
+
+/* Speck64 */
+
+struct speck64_xts_tfm_ctx {
+ struct speck64_tfm_ctx main_key;
+ struct speck64_tfm_ctx tweak_key;
+};
+
+asmlinkage void speck64_xts_encrypt_neon(const u32 *round_keys, int nrounds,
+ void *dst, const void *src,
+ unsigned int nbytes, void *tweak);
+
+asmlinkage void speck64_xts_decrypt_neon(const u32 *round_keys, int nrounds,
+ void *dst, const void *src,
+ unsigned int nbytes, void *tweak);
+
+typedef void (*speck64_crypt_one_t)(const struct speck64_tfm_ctx *,
+ u8 *, const u8 *);
+typedef void (*speck64_xts_crypt_many_t)(const u32 *, int, void *,
+ const void *, unsigned int, void *);
+
+static __always_inline int
+__speck64_xts_crypt(struct skcipher_request *req, speck64_crypt_one_t crypt_one,
+ speck64_xts_crypt_many_t crypt_many)
+{
+ struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+ const struct speck64_xts_tfm_ctx *ctx = crypto_skcipher_ctx(tfm);
+ struct skcipher_walk walk;
+ __le64 tweak;
+ int err;
+
+ err = skcipher_walk_virt(&walk, req, true);
+
+ crypto_speck64_encrypt(&ctx->tweak_key, (u8 *)&tweak, walk.iv);
+
+ while (walk.nbytes > 0) {
+ unsigned int nbytes = walk.nbytes;
+ u8 *dst = walk.dst.virt.addr;
+ const u8 *src = walk.src.virt.addr;
+
+ if (nbytes >= SPECK_NEON_CHUNK_SIZE && may_use_simd()) {
+ unsigned int count;
+
+ count = round_down(nbytes, SPECK_NEON_CHUNK_SIZE);
+ kernel_neon_begin();
+ (*crypt_many)(ctx->main_key.round_keys,
+ ctx->main_key.nrounds,
+ dst, src, count, &tweak);
+ kernel_neon_end();
+ dst += count;
+ src += count;
+ nbytes -= count;
+ }
+
+ /* Handle any remainder with generic code */
+ while (nbytes >= sizeof(tweak)) {
+ *(__le64 *)dst = *(__le64 *)src ^ tweak;
+ (*crypt_one)(&ctx->main_key, dst, dst);
+ *(__le64 *)dst ^= tweak;
+ tweak = cpu_to_le64((le64_to_cpu(tweak) << 1) ^
+ ((tweak & cpu_to_le64(1ULL << 63)) ?
+ 0x1B : 0));
+ dst += sizeof(tweak);
+ src += sizeof(tweak);
+ nbytes -= sizeof(tweak);
+ }
+ err = skcipher_walk_done(&walk, nbytes);
+ }
+
+ return err;
+}
+
+static int speck64_xts_encrypt(struct skcipher_request *req)
+{
+ return __speck64_xts_crypt(req, crypto_speck64_encrypt,
+ speck64_xts_encrypt_neon);
+}
+
+static int speck64_xts_decrypt(struct skcipher_request *req)
+{
+ return __speck64_xts_crypt(req, crypto_speck64_decrypt,
+ speck64_xts_decrypt_neon);
+}
+
+static int speck64_xts_setkey(struct crypto_skcipher *tfm, const u8 *key,
+ unsigned int keylen)
+{
+ struct speck64_xts_tfm_ctx *ctx = crypto_skcipher_ctx(tfm);
+ int err;
+
+ err = xts_verify_key(tfm, key, keylen);
+ if (err)
+ return err;
+
+ keylen /= 2;
+
+ err = crypto_speck64_setkey(&ctx->main_key, key, keylen);
+ if (err)
+ return err;
+
+ return crypto_speck64_setkey(&ctx->tweak_key, key + keylen, keylen);
+}
+
+static struct skcipher_alg speck_algs[] = {
+ {
+ .base.cra_name = "xts(speck128)",
+ .base.cra_driver_name = "xts-speck128-neon",
+ .base.cra_priority = 300,
+ .base.cra_blocksize = SPECK128_BLOCK_SIZE,
+ .base.cra_ctxsize = sizeof(struct speck128_xts_tfm_ctx),
+ .base.cra_alignmask = 7,
+ .base.cra_module = THIS_MODULE,
+ .min_keysize = 2 * SPECK128_128_KEY_SIZE,
+ .max_keysize = 2 * SPECK128_256_KEY_SIZE,
+ .ivsize = SPECK128_BLOCK_SIZE,
+ .walksize = SPECK_NEON_CHUNK_SIZE,
+ .setkey = speck128_xts_setkey,
+ .encrypt = speck128_xts_encrypt,
+ .decrypt = speck128_xts_decrypt,
+ }, {
+ .base.cra_name = "xts(speck64)",
+ .base.cra_driver_name = "xts-speck64-neon",
+ .base.cra_priority = 300,
+ .base.cra_blocksize = SPECK64_BLOCK_SIZE,
+ .base.cra_ctxsize = sizeof(struct speck64_xts_tfm_ctx),
+ .base.cra_alignmask = 7,
+ .base.cra_module = THIS_MODULE,
+ .min_keysize = 2 * SPECK64_96_KEY_SIZE,
+ .max_keysize = 2 * SPECK64_128_KEY_SIZE,
+ .ivsize = SPECK64_BLOCK_SIZE,
+ .walksize = SPECK_NEON_CHUNK_SIZE,
+ .setkey = speck64_xts_setkey,
+ .encrypt = speck64_xts_encrypt,
+ .decrypt = speck64_xts_decrypt,
+ }
+};
+
+static int __init speck_neon_module_init(void)
+{
+ if (!(elf_hwcap & HWCAP_NEON))
+ return -ENODEV;
+ return crypto_register_skciphers(speck_algs, ARRAY_SIZE(speck_algs));
+}
+
+static void __exit speck_neon_module_exit(void)
+{
+ crypto_unregister_skciphers(speck_algs, ARRAY_SIZE(speck_algs));
+}
+
+module_init(speck_neon_module_init);
+module_exit(speck_neon_module_exit);
+
+MODULE_DESCRIPTION("Speck block cipher (NEON-accelerated)");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Eric Biggers <ebiggers@google.com>");
+MODULE_ALIAS_CRYPTO("xts(speck128)");
+MODULE_ALIAS_CRYPTO("xts-speck128-neon");
+MODULE_ALIAS_CRYPTO("xts(speck64)");
+MODULE_ALIAS_CRYPTO("xts-speck64-neon");