--- /dev/null
+/*
+ * Accelerated GHASH implementation with ARMv8 vmull.p64 instructions.
+ *
+ * Copyright (C) 2015 Linaro Ltd. <ard.biesheuvel@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+
+#include <asm/hwcap.h>
+#include <asm/neon.h>
+#include <asm/simd.h>
+#include <asm/unaligned.h>
+#include <crypto/cryptd.h>
+#include <crypto/internal/hash.h>
+#include <crypto/gf128mul.h>
+#include <linux/crypto.h>
+#include <linux/module.h>
+
+MODULE_DESCRIPTION("GHASH secure hash using ARMv8 Crypto Extensions");
+MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
+MODULE_LICENSE("GPL v2");
+
+#define GHASH_BLOCK_SIZE 16
+#define GHASH_DIGEST_SIZE 16
+
+struct ghash_key {
+ u64 a;
+ u64 b;
+};
+
+struct ghash_desc_ctx {
+ u64 digest[GHASH_DIGEST_SIZE/sizeof(u64)];
+ u8 buf[GHASH_BLOCK_SIZE];
+ u32 count;
+};
+
+struct ghash_async_ctx {
+ struct cryptd_ahash *cryptd_tfm;
+};
+
+asmlinkage void pmull_ghash_update(int blocks, u64 dg[], const char *src,
+ struct ghash_key const *k, const char *head);
+
+static int ghash_init(struct shash_desc *desc)
+{
+ struct ghash_desc_ctx *ctx = shash_desc_ctx(desc);
+
+ *ctx = (struct ghash_desc_ctx){};
+ return 0;
+}
+
+static int ghash_update(struct shash_desc *desc, const u8 *src,
+ unsigned int len)
+{
+ struct ghash_desc_ctx *ctx = shash_desc_ctx(desc);
+ unsigned int partial = ctx->count % GHASH_BLOCK_SIZE;
+
+ ctx->count += len;
+
+ if ((partial + len) >= GHASH_BLOCK_SIZE) {
+ struct ghash_key *key = crypto_shash_ctx(desc->tfm);
+ int blocks;
+
+ if (partial) {
+ int p = GHASH_BLOCK_SIZE - partial;
+
+ memcpy(ctx->buf + partial, src, p);
+ src += p;
+ len -= p;
+ }
+
+ blocks = len / GHASH_BLOCK_SIZE;
+ len %= GHASH_BLOCK_SIZE;
+
+ kernel_neon_begin();
+ pmull_ghash_update(blocks, ctx->digest, src, key,
+ partial ? ctx->buf : NULL);
+ kernel_neon_end();
+ src += blocks * GHASH_BLOCK_SIZE;
+ partial = 0;
+ }
+ if (len)
+ memcpy(ctx->buf + partial, src, len);
+ return 0;
+}
+
+static int ghash_final(struct shash_desc *desc, u8 *dst)
+{
+ struct ghash_desc_ctx *ctx = shash_desc_ctx(desc);
+ unsigned int partial = ctx->count % GHASH_BLOCK_SIZE;
+
+ if (partial) {
+ struct ghash_key *key = crypto_shash_ctx(desc->tfm);
+
+ memset(ctx->buf + partial, 0, GHASH_BLOCK_SIZE - partial);
+ kernel_neon_begin();
+ pmull_ghash_update(1, ctx->digest, ctx->buf, key, NULL);
+ kernel_neon_end();
+ }
+ put_unaligned_be64(ctx->digest[1], dst);
+ put_unaligned_be64(ctx->digest[0], dst + 8);
+
+ *ctx = (struct ghash_desc_ctx){};
+ return 0;
+}
+
+static int ghash_setkey(struct crypto_shash *tfm,
+ const u8 *inkey, unsigned int keylen)
+{
+ struct ghash_key *key = crypto_shash_ctx(tfm);
+ u64 a, b;
+
+ if (keylen != GHASH_BLOCK_SIZE) {
+ crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
+ return -EINVAL;
+ }
+
+ /* perform multiplication by 'x' in GF(2^128) */
+ b = get_unaligned_be64(inkey);
+ a = get_unaligned_be64(inkey + 8);
+
+ key->a = (a << 1) | (b >> 63);
+ key->b = (b << 1) | (a >> 63);
+
+ if (b >> 63)
+ key->b ^= 0xc200000000000000UL;
+
+ return 0;
+}
+
+static struct shash_alg ghash_alg = {
+ .digestsize = GHASH_DIGEST_SIZE,
+ .init = ghash_init,
+ .update = ghash_update,
+ .final = ghash_final,
+ .setkey = ghash_setkey,
+ .descsize = sizeof(struct ghash_desc_ctx),
+ .base = {
+ .cra_name = "ghash",
+ .cra_driver_name = "__driver-ghash-ce",
+ .cra_priority = 0,
+ .cra_flags = CRYPTO_ALG_TYPE_SHASH | CRYPTO_ALG_INTERNAL,
+ .cra_blocksize = GHASH_BLOCK_SIZE,
+ .cra_ctxsize = sizeof(struct ghash_key),
+ .cra_module = THIS_MODULE,
+ },
+};
+
+static int ghash_async_init(struct ahash_request *req)
+{
+ struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+ struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
+ struct ahash_request *cryptd_req = ahash_request_ctx(req);
+ struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
+
+ if (!may_use_simd()) {
+ memcpy(cryptd_req, req, sizeof(*req));
+ ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
+ return crypto_ahash_init(cryptd_req);
+ } else {
+ struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
+ struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm);
+
+ desc->tfm = child;
+ desc->flags = req->base.flags;
+ return crypto_shash_init(desc);
+ }
+}
+
+static int ghash_async_update(struct ahash_request *req)
+{
+ struct ahash_request *cryptd_req = ahash_request_ctx(req);
+
+ if (!may_use_simd()) {
+ struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+ struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
+ struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
+
+ memcpy(cryptd_req, req, sizeof(*req));
+ ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
+ return crypto_ahash_update(cryptd_req);
+ } else {
+ struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
+ return shash_ahash_update(req, desc);
+ }
+}
+
+static int ghash_async_final(struct ahash_request *req)
+{
+ struct ahash_request *cryptd_req = ahash_request_ctx(req);
+
+ if (!may_use_simd()) {
+ struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+ struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
+ struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
+
+ memcpy(cryptd_req, req, sizeof(*req));
+ ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
+ return crypto_ahash_final(cryptd_req);
+ } else {
+ struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
+ return crypto_shash_final(desc, req->result);
+ }
+}
+
+static int ghash_async_digest(struct ahash_request *req)
+{
+ struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+ struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
+ struct ahash_request *cryptd_req = ahash_request_ctx(req);
+ struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm;
+
+ if (!may_use_simd()) {
+ memcpy(cryptd_req, req, sizeof(*req));
+ ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base);
+ return crypto_ahash_digest(cryptd_req);
+ } else {
+ struct shash_desc *desc = cryptd_shash_desc(cryptd_req);
+ struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm);
+
+ desc->tfm = child;
+ desc->flags = req->base.flags;
+ return shash_ahash_digest(req, desc);
+ }
+}
+
+static int ghash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
+ unsigned int keylen)
+{
+ struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm);
+ struct crypto_ahash *child = &ctx->cryptd_tfm->base;
+ int err;
+
+ crypto_ahash_clear_flags(child, CRYPTO_TFM_REQ_MASK);
+ crypto_ahash_set_flags(child, crypto_ahash_get_flags(tfm)
+ & CRYPTO_TFM_REQ_MASK);
+ err = crypto_ahash_setkey(child, key, keylen);
+ crypto_ahash_set_flags(tfm, crypto_ahash_get_flags(child)
+ & CRYPTO_TFM_RES_MASK);
+
+ return err;
+}
+
+static int ghash_async_init_tfm(struct crypto_tfm *tfm)
+{
+ struct cryptd_ahash *cryptd_tfm;
+ struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ cryptd_tfm = cryptd_alloc_ahash("__driver-ghash-ce",
+ CRYPTO_ALG_INTERNAL,
+ CRYPTO_ALG_INTERNAL);
+ if (IS_ERR(cryptd_tfm))
+ return PTR_ERR(cryptd_tfm);
+ ctx->cryptd_tfm = cryptd_tfm;
+ crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
+ sizeof(struct ahash_request) +
+ crypto_ahash_reqsize(&cryptd_tfm->base));
+
+ return 0;
+}
+
+static void ghash_async_exit_tfm(struct crypto_tfm *tfm)
+{
+ struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ cryptd_free_ahash(ctx->cryptd_tfm);
+}
+
+static struct ahash_alg ghash_async_alg = {
+ .init = ghash_async_init,
+ .update = ghash_async_update,
+ .final = ghash_async_final,
+ .setkey = ghash_async_setkey,
+ .digest = ghash_async_digest,
+ .halg.digestsize = GHASH_DIGEST_SIZE,
+ .halg.base = {
+ .cra_name = "ghash",
+ .cra_driver_name = "ghash-ce",
+ .cra_priority = 300,
+ .cra_flags = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC,
+ .cra_blocksize = GHASH_BLOCK_SIZE,
+ .cra_type = &crypto_ahash_type,
+ .cra_ctxsize = sizeof(struct ghash_async_ctx),
+ .cra_module = THIS_MODULE,
+ .cra_init = ghash_async_init_tfm,
+ .cra_exit = ghash_async_exit_tfm,
+ },
+};
+
+static int __init ghash_ce_mod_init(void)
+{
+ int err;
+
+ if (!(elf_hwcap2 & HWCAP2_PMULL))
+ return -ENODEV;
+
+ err = crypto_register_shash(&ghash_alg);
+ if (err)
+ return err;
+ err = crypto_register_ahash(&ghash_async_alg);
+ if (err)
+ goto err_shash;
+
+ return 0;
+
+err_shash:
+ crypto_unregister_shash(&ghash_alg);
+ return err;
+}
+
+static void __exit ghash_ce_mod_exit(void)
+{
+ crypto_unregister_ahash(&ghash_async_alg);
+ crypto_unregister_shash(&ghash_alg);
+}
+
+module_init(ghash_ce_mod_init);
+module_exit(ghash_ce_mod_exit);
Code Review / kvmfornfv.git / blobdiff