ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/crypto/ghash-generic.c b/marvell/linux/crypto/ghash-generic.c
new file mode 100644
index 0000000..5027b34
--- /dev/null
+++ b/marvell/linux/crypto/ghash-generic.c
@@ -0,0 +1,186 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * GHASH: hash function for GCM (Galois/Counter Mode).
+ *
+ * Copyright (c) 2007 Nokia Siemens Networks - Mikko Herranen <mh1@iki.fi>
+ * Copyright (c) 2009 Intel Corp.
+ * Author: Huang Ying <ying.huang@intel.com>
+ */
+
+/*
+ * GHASH is a keyed hash function used in GCM authentication tag generation.
+ *
+ * The original GCM paper [1] presents GHASH as a function GHASH(H, A, C) which
+ * takes a 16-byte hash key H, additional authenticated data A, and a ciphertext
+ * C. It formats A and C into a single byte string X, interprets X as a
+ * polynomial over GF(2^128), and evaluates this polynomial at the point H.
+ *
+ * However, the NIST standard for GCM [2] presents GHASH as GHASH(H, X) where X
+ * is the already-formatted byte string containing both A and C.
+ *
+ * "ghash" in the Linux crypto API uses the 'X' (pre-formatted) convention,
+ * since the API supports only a single data stream per hash. Thus, the
+ * formatting of 'A' and 'C' is done in the "gcm" template, not in "ghash".
+ *
+ * The reason "ghash" is separate from "gcm" is to allow "gcm" to use an
+ * accelerated "ghash" when a standalone accelerated "gcm(aes)" is unavailable.
+ * It is generally inappropriate to use "ghash" for other purposes, since it is
+ * an "ε-almost-XOR-universal hash function", not a cryptographic hash function.
+ * It can only be used securely in crypto modes specially designed to use it.
+ *
+ * [1] The Galois/Counter Mode of Operation (GCM)
+ * (http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.694.695&rep=rep1&type=pdf)
+ * [2] Recommendation for Block Cipher Modes of Operation: Galois/Counter Mode (GCM) and GMAC
+ * (https://csrc.nist.gov/publications/detail/sp/800-38d/final)
+ */
+
+#include <crypto/algapi.h>
+#include <crypto/gf128mul.h>
+#include <crypto/ghash.h>
+#include <crypto/internal/hash.h>
+#include <linux/crypto.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+static int ghash_init(struct shash_desc *desc)
+{
+ struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
+
+ memset(dctx, 0, sizeof(*dctx));
+
+ return 0;
+}
+
+static int ghash_setkey(struct crypto_shash *tfm,
+ const u8 *key, unsigned int keylen)
+{
+ struct ghash_ctx *ctx = crypto_shash_ctx(tfm);
+ be128 k;
+
+ if (keylen != GHASH_BLOCK_SIZE) {
+ crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
+ return -EINVAL;
+ }
+
+ if (ctx->gf128)
+ gf128mul_free_4k(ctx->gf128);
+
+ BUILD_BUG_ON(sizeof(k) != GHASH_BLOCK_SIZE);
+ memcpy(&k, key, GHASH_BLOCK_SIZE); /* avoid violating alignment rules */
+ ctx->gf128 = gf128mul_init_4k_lle(&k);
+ memzero_explicit(&k, GHASH_BLOCK_SIZE);
+
+ if (!ctx->gf128)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static int ghash_update(struct shash_desc *desc,
+ const u8 *src, unsigned int srclen)
+{
+ struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
+ struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
+ u8 *dst = dctx->buffer;
+
+ if (dctx->bytes) {
+ int n = min(srclen, dctx->bytes);
+ u8 *pos = dst + (GHASH_BLOCK_SIZE - dctx->bytes);
+
+ dctx->bytes -= n;
+ srclen -= n;
+
+ while (n--)
+ *pos++ ^= *src++;
+
+ if (!dctx->bytes)
+ gf128mul_4k_lle((be128 *)dst, ctx->gf128);
+ }
+
+ while (srclen >= GHASH_BLOCK_SIZE) {
+ crypto_xor(dst, src, GHASH_BLOCK_SIZE);
+ gf128mul_4k_lle((be128 *)dst, ctx->gf128);
+ src += GHASH_BLOCK_SIZE;
+ srclen -= GHASH_BLOCK_SIZE;
+ }
+
+ if (srclen) {
+ dctx->bytes = GHASH_BLOCK_SIZE - srclen;
+ while (srclen--)
+ *dst++ ^= *src++;
+ }
+
+ return 0;
+}
+
+static void ghash_flush(struct ghash_ctx *ctx, struct ghash_desc_ctx *dctx)
+{
+ u8 *dst = dctx->buffer;
+
+ if (dctx->bytes) {
+ u8 *tmp = dst + (GHASH_BLOCK_SIZE - dctx->bytes);
+
+ while (dctx->bytes--)
+ *tmp++ ^= 0;
+
+ gf128mul_4k_lle((be128 *)dst, ctx->gf128);
+ }
+
+ dctx->bytes = 0;
+}
+
+static int ghash_final(struct shash_desc *desc, u8 *dst)
+{
+ struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
+ struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
+ u8 *buf = dctx->buffer;
+
+ ghash_flush(ctx, dctx);
+ memcpy(dst, buf, GHASH_BLOCK_SIZE);
+
+ return 0;
+}
+
+static void ghash_exit_tfm(struct crypto_tfm *tfm)
+{
+ struct ghash_ctx *ctx = crypto_tfm_ctx(tfm);
+ if (ctx->gf128)
+ gf128mul_free_4k(ctx->gf128);
+}
+
+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 = "ghash-generic",
+ .cra_priority = 100,
+ .cra_blocksize = GHASH_BLOCK_SIZE,
+ .cra_ctxsize = sizeof(struct ghash_ctx),
+ .cra_module = THIS_MODULE,
+ .cra_exit = ghash_exit_tfm,
+ },
+};
+
+static int __init ghash_mod_init(void)
+{
+ return crypto_register_shash(&ghash_alg);
+}
+
+static void __exit ghash_mod_exit(void)
+{
+ crypto_unregister_shash(&ghash_alg);
+}
+
+subsys_initcall(ghash_mod_init);
+module_exit(ghash_mod_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("GHASH hash function");
+MODULE_ALIAS_CRYPTO("ghash");
+MODULE_ALIAS_CRYPTO("ghash-generic");