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-rw-r--r--arch/arm64/crypto/ghash-ce-glue.c545
1 files changed, 545 insertions, 0 deletions
diff --git a/arch/arm64/crypto/ghash-ce-glue.c b/arch/arm64/crypto/ghash-ce-glue.c
new file mode 100644
index 000000000000..7951557a285a
--- /dev/null
+++ b/arch/arm64/crypto/ghash-ce-glue.c
@@ -0,0 +1,545 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Accelerated GHASH implementation with ARMv8 PMULL instructions.
+ *
+ * Copyright (C) 2014 - 2018 Linaro Ltd. <ard.biesheuvel@linaro.org>
+ */
+
+#include <crypto/aes.h>
+#include <crypto/b128ops.h>
+#include <crypto/gcm.h>
+#include <crypto/ghash.h>
+#include <crypto/gf128mul.h>
+#include <crypto/internal/aead.h>
+#include <crypto/internal/hash.h>
+#include <crypto/internal/skcipher.h>
+#include <crypto/scatterwalk.h>
+#include <linux/cpufeature.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/unaligned.h>
+
+#include <asm/simd.h>
+
+MODULE_DESCRIPTION("GHASH and AES-GCM using ARMv8 Crypto Extensions");
+MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS_CRYPTO("ghash");
+
+#define RFC4106_NONCE_SIZE 4
+
+struct ghash_key {
+ be128 k;
+ u64 h[][2];
+};
+
+struct arm_ghash_desc_ctx {
+ u64 digest[GHASH_DIGEST_SIZE/sizeof(u64)];
+};
+
+struct gcm_aes_ctx {
+ struct crypto_aes_ctx aes_key;
+ u8 nonce[RFC4106_NONCE_SIZE];
+ struct ghash_key ghash_key;
+};
+
+asmlinkage void pmull_ghash_update_p64(int blocks, u64 dg[], const char *src,
+ u64 const h[][2], const char *head);
+
+asmlinkage void pmull_ghash_update_p8(int blocks, u64 dg[], const char *src,
+ u64 const h[][2], const char *head);
+
+asmlinkage void pmull_gcm_encrypt(int bytes, u8 dst[], const u8 src[],
+ u64 const h[][2], u64 dg[], u8 ctr[],
+ u32 const rk[], int rounds, u8 tag[]);
+asmlinkage int pmull_gcm_decrypt(int bytes, u8 dst[], const u8 src[],
+ u64 const h[][2], u64 dg[], u8 ctr[],
+ u32 const rk[], int rounds, const u8 l[],
+ const u8 tag[], u64 authsize);
+
+static int ghash_init(struct shash_desc *desc)
+{
+ struct arm_ghash_desc_ctx *ctx = shash_desc_ctx(desc);
+
+ *ctx = (struct arm_ghash_desc_ctx){};
+ return 0;
+}
+
+static __always_inline
+void ghash_do_simd_update(int blocks, u64 dg[], const char *src,
+ struct ghash_key *key, const char *head,
+ void (*simd_update)(int blocks, u64 dg[],
+ const char *src,
+ u64 const h[][2],
+ const char *head))
+{
+ scoped_ksimd()
+ simd_update(blocks, dg, src, key->h, head);
+}
+
+/* avoid hogging the CPU for too long */
+#define MAX_BLOCKS (SZ_64K / GHASH_BLOCK_SIZE)
+
+static int ghash_update(struct shash_desc *desc, const u8 *src,
+ unsigned int len)
+{
+ struct arm_ghash_desc_ctx *ctx = shash_desc_ctx(desc);
+ struct ghash_key *key = crypto_shash_ctx(desc->tfm);
+ int blocks;
+
+ blocks = len / GHASH_BLOCK_SIZE;
+ len -= blocks * GHASH_BLOCK_SIZE;
+
+ do {
+ int chunk = min(blocks, MAX_BLOCKS);
+
+ ghash_do_simd_update(chunk, ctx->digest, src, key, NULL,
+ pmull_ghash_update_p8);
+ blocks -= chunk;
+ src += chunk * GHASH_BLOCK_SIZE;
+ } while (unlikely(blocks > 0));
+ return len;
+}
+
+static int ghash_export(struct shash_desc *desc, void *out)
+{
+ struct arm_ghash_desc_ctx *ctx = shash_desc_ctx(desc);
+ u8 *dst = out;
+
+ put_unaligned_be64(ctx->digest[1], dst);
+ put_unaligned_be64(ctx->digest[0], dst + 8);
+ return 0;
+}
+
+static int ghash_import(struct shash_desc *desc, const void *in)
+{
+ struct arm_ghash_desc_ctx *ctx = shash_desc_ctx(desc);
+ const u8 *src = in;
+
+ ctx->digest[1] = get_unaligned_be64(src);
+ ctx->digest[0] = get_unaligned_be64(src + 8);
+ return 0;
+}
+
+static int ghash_finup(struct shash_desc *desc, const u8 *src,
+ unsigned int len, u8 *dst)
+{
+ struct arm_ghash_desc_ctx *ctx = shash_desc_ctx(desc);
+ struct ghash_key *key = crypto_shash_ctx(desc->tfm);
+
+ if (len) {
+ u8 buf[GHASH_BLOCK_SIZE] = {};
+
+ memcpy(buf, src, len);
+ ghash_do_simd_update(1, ctx->digest, src, key, NULL,
+ pmull_ghash_update_p8);
+ memzero_explicit(buf, sizeof(buf));
+ }
+ return ghash_export(desc, dst);
+}
+
+static void ghash_reflect(u64 h[], const be128 *k)
+{
+ u64 carry = be64_to_cpu(k->a) & BIT(63) ? 1 : 0;
+
+ h[0] = (be64_to_cpu(k->b) << 1) | carry;
+ h[1] = (be64_to_cpu(k->a) << 1) | (be64_to_cpu(k->b) >> 63);
+
+ if (carry)
+ h[1] ^= 0xc200000000000000UL;
+}
+
+static int ghash_setkey(struct crypto_shash *tfm,
+ const u8 *inkey, unsigned int keylen)
+{
+ struct ghash_key *key = crypto_shash_ctx(tfm);
+
+ if (keylen != GHASH_BLOCK_SIZE)
+ return -EINVAL;
+
+ /* needed for the fallback */
+ memcpy(&key->k, inkey, GHASH_BLOCK_SIZE);
+
+ ghash_reflect(key->h[0], &key->k);
+ return 0;
+}
+
+static struct shash_alg ghash_alg = {
+ .base.cra_name = "ghash",
+ .base.cra_driver_name = "ghash-neon",
+ .base.cra_priority = 150,
+ .base.cra_flags = CRYPTO_AHASH_ALG_BLOCK_ONLY,
+ .base.cra_blocksize = GHASH_BLOCK_SIZE,
+ .base.cra_ctxsize = sizeof(struct ghash_key) + sizeof(u64[2]),
+ .base.cra_module = THIS_MODULE,
+
+ .digestsize = GHASH_DIGEST_SIZE,
+ .init = ghash_init,
+ .update = ghash_update,
+ .finup = ghash_finup,
+ .setkey = ghash_setkey,
+ .export = ghash_export,
+ .import = ghash_import,
+ .descsize = sizeof(struct arm_ghash_desc_ctx),
+ .statesize = sizeof(struct ghash_desc_ctx),
+};
+
+static int num_rounds(struct crypto_aes_ctx *ctx)
+{
+ /*
+ * # of rounds specified by AES:
+ * 128 bit key 10 rounds
+ * 192 bit key 12 rounds
+ * 256 bit key 14 rounds
+ * => n byte key => 6 + (n/4) rounds
+ */
+ return 6 + ctx->key_length / 4;
+}
+
+static int gcm_aes_setkey(struct crypto_aead *tfm, const u8 *inkey,
+ unsigned int keylen)
+{
+ struct gcm_aes_ctx *ctx = crypto_aead_ctx(tfm);
+ u8 key[GHASH_BLOCK_SIZE];
+ be128 h;
+ int ret;
+
+ ret = aes_expandkey(&ctx->aes_key, inkey, keylen);
+ if (ret)
+ return -EINVAL;
+
+ aes_encrypt(&ctx->aes_key, key, (u8[AES_BLOCK_SIZE]){});
+
+ /* needed for the fallback */
+ memcpy(&ctx->ghash_key.k, key, GHASH_BLOCK_SIZE);
+
+ ghash_reflect(ctx->ghash_key.h[0], &ctx->ghash_key.k);
+
+ h = ctx->ghash_key.k;
+ gf128mul_lle(&h, &ctx->ghash_key.k);
+ ghash_reflect(ctx->ghash_key.h[1], &h);
+
+ gf128mul_lle(&h, &ctx->ghash_key.k);
+ ghash_reflect(ctx->ghash_key.h[2], &h);
+
+ gf128mul_lle(&h, &ctx->ghash_key.k);
+ ghash_reflect(ctx->ghash_key.h[3], &h);
+
+ return 0;
+}
+
+static int gcm_aes_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
+{
+ return crypto_gcm_check_authsize(authsize);
+}
+
+static void gcm_update_mac(u64 dg[], const u8 *src, int count, u8 buf[],
+ int *buf_count, struct gcm_aes_ctx *ctx)
+{
+ if (*buf_count > 0) {
+ int buf_added = min(count, GHASH_BLOCK_SIZE - *buf_count);
+
+ memcpy(&buf[*buf_count], src, buf_added);
+
+ *buf_count += buf_added;
+ src += buf_added;
+ count -= buf_added;
+ }
+
+ if (count >= GHASH_BLOCK_SIZE || *buf_count == GHASH_BLOCK_SIZE) {
+ int blocks = count / GHASH_BLOCK_SIZE;
+
+ ghash_do_simd_update(blocks, dg, src, &ctx->ghash_key,
+ *buf_count ? buf : NULL,
+ pmull_ghash_update_p64);
+
+ src += blocks * GHASH_BLOCK_SIZE;
+ count %= GHASH_BLOCK_SIZE;
+ *buf_count = 0;
+ }
+
+ if (count > 0) {
+ memcpy(buf, src, count);
+ *buf_count = count;
+ }
+}
+
+static void gcm_calculate_auth_mac(struct aead_request *req, u64 dg[], u32 len)
+{
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ struct gcm_aes_ctx *ctx = crypto_aead_ctx(aead);
+ u8 buf[GHASH_BLOCK_SIZE];
+ struct scatter_walk walk;
+ int buf_count = 0;
+
+ scatterwalk_start(&walk, req->src);
+
+ do {
+ unsigned int n;
+
+ n = scatterwalk_next(&walk, len);
+ gcm_update_mac(dg, walk.addr, n, buf, &buf_count, ctx);
+ scatterwalk_done_src(&walk, n);
+ len -= n;
+ } while (len);
+
+ if (buf_count) {
+ memset(&buf[buf_count], 0, GHASH_BLOCK_SIZE - buf_count);
+ ghash_do_simd_update(1, dg, buf, &ctx->ghash_key, NULL,
+ pmull_ghash_update_p64);
+ }
+}
+
+static int gcm_encrypt(struct aead_request *req, char *iv, int assoclen)
+{
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ struct gcm_aes_ctx *ctx = crypto_aead_ctx(aead);
+ int nrounds = num_rounds(&ctx->aes_key);
+ struct skcipher_walk walk;
+ u8 buf[AES_BLOCK_SIZE];
+ u64 dg[2] = {};
+ be128 lengths;
+ u8 *tag;
+ int err;
+
+ lengths.a = cpu_to_be64(assoclen * 8);
+ lengths.b = cpu_to_be64(req->cryptlen * 8);
+
+ if (assoclen)
+ gcm_calculate_auth_mac(req, dg, assoclen);
+
+ put_unaligned_be32(2, iv + GCM_AES_IV_SIZE);
+
+ err = skcipher_walk_aead_encrypt(&walk, req, false);
+
+ do {
+ const u8 *src = walk.src.virt.addr;
+ u8 *dst = walk.dst.virt.addr;
+ int nbytes = walk.nbytes;
+
+ tag = (u8 *)&lengths;
+
+ if (unlikely(nbytes > 0 && nbytes < AES_BLOCK_SIZE)) {
+ src = dst = memcpy(buf + sizeof(buf) - nbytes,
+ src, nbytes);
+ } else if (nbytes < walk.total) {
+ nbytes &= ~(AES_BLOCK_SIZE - 1);
+ tag = NULL;
+ }
+
+ scoped_ksimd()
+ pmull_gcm_encrypt(nbytes, dst, src, ctx->ghash_key.h,
+ dg, iv, ctx->aes_key.key_enc, nrounds,
+ tag);
+
+ if (unlikely(!nbytes))
+ break;
+
+ if (unlikely(nbytes > 0 && nbytes < AES_BLOCK_SIZE))
+ memcpy(walk.dst.virt.addr,
+ buf + sizeof(buf) - nbytes, nbytes);
+
+ err = skcipher_walk_done(&walk, walk.nbytes - nbytes);
+ } while (walk.nbytes);
+
+ if (err)
+ return err;
+
+ /* copy authtag to end of dst */
+ scatterwalk_map_and_copy(tag, req->dst, req->assoclen + req->cryptlen,
+ crypto_aead_authsize(aead), 1);
+
+ return 0;
+}
+
+static int gcm_decrypt(struct aead_request *req, char *iv, int assoclen)
+{
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ struct gcm_aes_ctx *ctx = crypto_aead_ctx(aead);
+ unsigned int authsize = crypto_aead_authsize(aead);
+ int nrounds = num_rounds(&ctx->aes_key);
+ struct skcipher_walk walk;
+ u8 otag[AES_BLOCK_SIZE];
+ u8 buf[AES_BLOCK_SIZE];
+ u64 dg[2] = {};
+ be128 lengths;
+ u8 *tag;
+ int ret;
+ int err;
+
+ lengths.a = cpu_to_be64(assoclen * 8);
+ lengths.b = cpu_to_be64((req->cryptlen - authsize) * 8);
+
+ if (assoclen)
+ gcm_calculate_auth_mac(req, dg, assoclen);
+
+ put_unaligned_be32(2, iv + GCM_AES_IV_SIZE);
+
+ scatterwalk_map_and_copy(otag, req->src,
+ req->assoclen + req->cryptlen - authsize,
+ authsize, 0);
+
+ err = skcipher_walk_aead_decrypt(&walk, req, false);
+
+ do {
+ const u8 *src = walk.src.virt.addr;
+ u8 *dst = walk.dst.virt.addr;
+ int nbytes = walk.nbytes;
+
+ tag = (u8 *)&lengths;
+
+ if (unlikely(nbytes > 0 && nbytes < AES_BLOCK_SIZE)) {
+ src = dst = memcpy(buf + sizeof(buf) - nbytes,
+ src, nbytes);
+ } else if (nbytes < walk.total) {
+ nbytes &= ~(AES_BLOCK_SIZE - 1);
+ tag = NULL;
+ }
+
+ scoped_ksimd()
+ ret = pmull_gcm_decrypt(nbytes, dst, src,
+ ctx->ghash_key.h,
+ dg, iv, ctx->aes_key.key_enc,
+ nrounds, tag, otag, authsize);
+
+ if (unlikely(!nbytes))
+ break;
+
+ if (unlikely(nbytes > 0 && nbytes < AES_BLOCK_SIZE))
+ memcpy(walk.dst.virt.addr,
+ buf + sizeof(buf) - nbytes, nbytes);
+
+ err = skcipher_walk_done(&walk, walk.nbytes - nbytes);
+ } while (walk.nbytes);
+
+ if (err)
+ return err;
+
+ return ret ? -EBADMSG : 0;
+}
+
+static int gcm_aes_encrypt(struct aead_request *req)
+{
+ u8 iv[AES_BLOCK_SIZE];
+
+ memcpy(iv, req->iv, GCM_AES_IV_SIZE);
+ return gcm_encrypt(req, iv, req->assoclen);
+}
+
+static int gcm_aes_decrypt(struct aead_request *req)
+{
+ u8 iv[AES_BLOCK_SIZE];
+
+ memcpy(iv, req->iv, GCM_AES_IV_SIZE);
+ return gcm_decrypt(req, iv, req->assoclen);
+}
+
+static int rfc4106_setkey(struct crypto_aead *tfm, const u8 *inkey,
+ unsigned int keylen)
+{
+ struct gcm_aes_ctx *ctx = crypto_aead_ctx(tfm);
+ int err;
+
+ keylen -= RFC4106_NONCE_SIZE;
+ err = gcm_aes_setkey(tfm, inkey, keylen);
+ if (err)
+ return err;
+
+ memcpy(ctx->nonce, inkey + keylen, RFC4106_NONCE_SIZE);
+ return 0;
+}
+
+static int rfc4106_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
+{
+ return crypto_rfc4106_check_authsize(authsize);
+}
+
+static int rfc4106_encrypt(struct aead_request *req)
+{
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ struct gcm_aes_ctx *ctx = crypto_aead_ctx(aead);
+ u8 iv[AES_BLOCK_SIZE];
+
+ memcpy(iv, ctx->nonce, RFC4106_NONCE_SIZE);
+ memcpy(iv + RFC4106_NONCE_SIZE, req->iv, GCM_RFC4106_IV_SIZE);
+
+ return crypto_ipsec_check_assoclen(req->assoclen) ?:
+ gcm_encrypt(req, iv, req->assoclen - GCM_RFC4106_IV_SIZE);
+}
+
+static int rfc4106_decrypt(struct aead_request *req)
+{
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ struct gcm_aes_ctx *ctx = crypto_aead_ctx(aead);
+ u8 iv[AES_BLOCK_SIZE];
+
+ memcpy(iv, ctx->nonce, RFC4106_NONCE_SIZE);
+ memcpy(iv + RFC4106_NONCE_SIZE, req->iv, GCM_RFC4106_IV_SIZE);
+
+ return crypto_ipsec_check_assoclen(req->assoclen) ?:
+ gcm_decrypt(req, iv, req->assoclen - GCM_RFC4106_IV_SIZE);
+}
+
+static struct aead_alg gcm_aes_algs[] = {{
+ .ivsize = GCM_AES_IV_SIZE,
+ .chunksize = AES_BLOCK_SIZE,
+ .maxauthsize = AES_BLOCK_SIZE,
+ .setkey = gcm_aes_setkey,
+ .setauthsize = gcm_aes_setauthsize,
+ .encrypt = gcm_aes_encrypt,
+ .decrypt = gcm_aes_decrypt,
+
+ .base.cra_name = "gcm(aes)",
+ .base.cra_driver_name = "gcm-aes-ce",
+ .base.cra_priority = 300,
+ .base.cra_blocksize = 1,
+ .base.cra_ctxsize = sizeof(struct gcm_aes_ctx) +
+ 4 * sizeof(u64[2]),
+ .base.cra_module = THIS_MODULE,
+}, {
+ .ivsize = GCM_RFC4106_IV_SIZE,
+ .chunksize = AES_BLOCK_SIZE,
+ .maxauthsize = AES_BLOCK_SIZE,
+ .setkey = rfc4106_setkey,
+ .setauthsize = rfc4106_setauthsize,
+ .encrypt = rfc4106_encrypt,
+ .decrypt = rfc4106_decrypt,
+
+ .base.cra_name = "rfc4106(gcm(aes))",
+ .base.cra_driver_name = "rfc4106-gcm-aes-ce",
+ .base.cra_priority = 300,
+ .base.cra_blocksize = 1,
+ .base.cra_ctxsize = sizeof(struct gcm_aes_ctx) +
+ 4 * sizeof(u64[2]),
+ .base.cra_module = THIS_MODULE,
+}};
+
+static int __init ghash_ce_mod_init(void)
+{
+ if (!cpu_have_named_feature(ASIMD))
+ return -ENODEV;
+
+ if (cpu_have_named_feature(PMULL))
+ return crypto_register_aeads(gcm_aes_algs,
+ ARRAY_SIZE(gcm_aes_algs));
+
+ return crypto_register_shash(&ghash_alg);
+}
+
+static void __exit ghash_ce_mod_exit(void)
+{
+ if (cpu_have_named_feature(PMULL))
+ crypto_unregister_aeads(gcm_aes_algs, ARRAY_SIZE(gcm_aes_algs));
+ else
+ crypto_unregister_shash(&ghash_alg);
+}
+
+static const struct cpu_feature __maybe_unused ghash_cpu_feature[] = {
+ { cpu_feature(PMULL) }, { }
+};
+MODULE_DEVICE_TABLE(cpu, ghash_cpu_feature);
+
+module_init(ghash_ce_mod_init);
+module_exit(ghash_ce_mod_exit);
generated by cgit (git 2.34.1) at 2025-12-26 10:08:04 +0000