[RFC PATCH 06/13] crypto: riscv - add vector crypto accelerated AES

From: Eric Biggers
Date: Tue Jan 02 2024 - 01:52:07 EST


From: Jerry Shih <jerry.shih@xxxxxxxxxx>

Add an implementation of AES using the Zvkned extension. The assembly
code is derived from OpenSSL code (openssl/openssl#21923) that was
dual-licensed so that it could be reused in the kernel. Nevertheless,
the assembly has been significantly reworked for integration with the
kernel, for example by using a regular .S file instead of the so-called
perlasm, using the assembler instead of bare '.inst', greatly reducing
code duplication, supporting AES-192, and making the code use the same
AES key structure as the C code.

Co-developed-by: Christoph Müllner <christoph.muellner@xxxxxxxx>
Signed-off-by: Christoph Müllner <christoph.muellner@xxxxxxxx>
Co-developed-by: Heiko Stuebner <heiko.stuebner@xxxxxxxx>
Signed-off-by: Heiko Stuebner <heiko.stuebner@xxxxxxxx>
Co-developed-by: Phoebe Chen <phoebe.chen@xxxxxxxxxx>
Signed-off-by: Phoebe Chen <phoebe.chen@xxxxxxxxxx>
Signed-off-by: Jerry Shih <jerry.shih@xxxxxxxxxx>
Co-developed-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
---
arch/riscv/crypto/Kconfig | 11 ++
arch/riscv/crypto/Makefile | 3 +
arch/riscv/crypto/aes-macros.S | 156 +++++++++++++++++++++++++
arch/riscv/crypto/aes-riscv64-glue.c | 123 +++++++++++++++++++
arch/riscv/crypto/aes-riscv64-glue.h | 15 +++
arch/riscv/crypto/aes-riscv64-zvkned.S | 84 +++++++++++++
6 files changed, 392 insertions(+)
create mode 100644 arch/riscv/crypto/aes-macros.S
create mode 100644 arch/riscv/crypto/aes-riscv64-glue.c
create mode 100644 arch/riscv/crypto/aes-riscv64-glue.h
create mode 100644 arch/riscv/crypto/aes-riscv64-zvkned.S

diff --git a/arch/riscv/crypto/Kconfig b/arch/riscv/crypto/Kconfig
index 10d60edc0110a..2a7c365f2a86c 100644
--- a/arch/riscv/crypto/Kconfig
+++ b/arch/riscv/crypto/Kconfig
@@ -1,5 +1,16 @@
# SPDX-License-Identifier: GPL-2.0

menu "Accelerated Cryptographic Algorithms for CPU (riscv)"

+config CRYPTO_AES_RISCV64
+ tristate "Ciphers: AES"
+ depends on 64BIT && RISCV_ISA_V && TOOLCHAIN_HAS_VECTOR_CRYPTO
+ select CRYPTO_ALGAPI
+ select CRYPTO_LIB_AES
+ help
+ Block ciphers: AES cipher algorithms (FIPS-197)
+
+ Architecture: riscv64 using:
+ - Zvkned vector crypto extension
+
endmenu
diff --git a/arch/riscv/crypto/Makefile b/arch/riscv/crypto/Makefile
index b3b6332c9f6d0..dca698c5cba3e 100644
--- a/arch/riscv/crypto/Makefile
+++ b/arch/riscv/crypto/Makefile
@@ -1,4 +1,7 @@
# SPDX-License-Identifier: GPL-2.0-only
#
# linux/arch/riscv/crypto/Makefile
#
+
+obj-$(CONFIG_CRYPTO_AES_RISCV64) += aes-riscv64.o
+aes-riscv64-y := aes-riscv64-glue.o aes-riscv64-zvkned.o
diff --git a/arch/riscv/crypto/aes-macros.S b/arch/riscv/crypto/aes-macros.S
new file mode 100644
index 0000000000000..2ada0c70f4a6a
--- /dev/null
+++ b/arch/riscv/crypto/aes-macros.S
@@ -0,0 +1,156 @@
+/* SPDX-License-Identifier: Apache-2.0 OR BSD-2-Clause */
+//
+// This file is dual-licensed, meaning that you can use it under your
+// choice of either of the following two licenses:
+//
+// Copyright 2023 The OpenSSL Project Authors. All Rights Reserved.
+//
+// Licensed under the Apache License 2.0 (the "License"). You can obtain
+// a copy in the file LICENSE in the source distribution or at
+// https://www.openssl.org/source/license.html
+//
+// or
+//
+// Copyright (c) 2023, Christoph Müllner <christoph.muellner@xxxxxxxx>
+// Copyright (c) 2023, Phoebe Chen <phoebe.chen@xxxxxxxxxx>
+// Copyright (c) 2023, Jerry Shih <jerry.shih@xxxxxxxxxx>
+// Copyright 2024 Google LLC
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions
+// are met:
+// 1. Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright
+// notice, this list of conditions and the following disclaimer in the
+// documentation and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. INP NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER INP CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING INP ANY WAY OUTP OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// This file contains macros that are shared by the other aes-*.S files. The
+// generated code of these macros depends on the following RISC-V extensions:
+// - RV64I
+// - RISC-V Vector ('V') with VLEN >= 128
+// - RISC-V Vector AES block cipher extension ('Zvkned')
+
+// Loads the AES round keys from \keyp into vector registers and jumps to code
+// specific to the length of the key. Specifically:
+// - If AES-128, loads round keys into v1-v11 and jumps to \label128.
+// - If AES-192, loads round keys into v1-v13 and jumps to \label192.
+// - If AES-256, loads round keys into v1-v15 and continues onwards.
+//
+// Also sets vl=4 and vtype=e32,m1,ta,ma. Clobbers t0 and t1.
+.macro aes_begin keyp, label128, label192
+ lwu t0, 480(\keyp) // t0 = key length in bytes
+ li t1, 24 // t1 = key length for AES-192
+ vsetivli zero, 4, e32, m1, ta, ma
+ vle32.v v1, (\keyp)
+ addi \keyp, \keyp, 16
+ vle32.v v2, (\keyp)
+ addi \keyp, \keyp, 16
+ vle32.v v3, (\keyp)
+ addi \keyp, \keyp, 16
+ vle32.v v4, (\keyp)
+ addi \keyp, \keyp, 16
+ vle32.v v5, (\keyp)
+ addi \keyp, \keyp, 16
+ vle32.v v6, (\keyp)
+ addi \keyp, \keyp, 16
+ vle32.v v7, (\keyp)
+ addi \keyp, \keyp, 16
+ vle32.v v8, (\keyp)
+ addi \keyp, \keyp, 16
+ vle32.v v9, (\keyp)
+ addi \keyp, \keyp, 16
+ vle32.v v10, (\keyp)
+ addi \keyp, \keyp, 16
+ vle32.v v11, (\keyp)
+ blt t0, t1, \label128 // If AES-128, goto label128.
+ addi \keyp, \keyp, 16
+ vle32.v v12, (\keyp)
+ addi \keyp, \keyp, 16
+ vle32.v v13, (\keyp)
+ beq t0, t1, \label192 // If AES-192, goto label192.
+ // Else, it's AES-256.
+ addi \keyp, \keyp, 16
+ vle32.v v14, (\keyp)
+ addi \keyp, \keyp, 16
+ vle32.v v15, (\keyp)
+.endm
+
+// Encrypts \data using zvkned instructions, using the round keys loaded into
+// v1-v11 (for AES-128), v1-v13 (for AES-192), or v1-v15 (for AES-256). \keylen
+// is the AES key length in bits. vl and vtype must already be set
+// appropriately. Note that if vl > 4, multiple blocks are encrypted.
+.macro aes_encrypt data, keylen
+ vaesz.vs \data, v1
+ vaesem.vs \data, v2
+ vaesem.vs \data, v3
+ vaesem.vs \data, v4
+ vaesem.vs \data, v5
+ vaesem.vs \data, v6
+ vaesem.vs \data, v7
+ vaesem.vs \data, v8
+ vaesem.vs \data, v9
+ vaesem.vs \data, v10
+.if \keylen == 128
+ vaesef.vs \data, v11
+.elseif \keylen == 192
+ vaesem.vs \data, v11
+ vaesem.vs \data, v12
+ vaesef.vs \data, v13
+.else
+ vaesem.vs \data, v11
+ vaesem.vs \data, v12
+ vaesem.vs \data, v13
+ vaesem.vs \data, v14
+ vaesef.vs \data, v15
+.endif
+.endm
+
+// Same as aes_encrypt, but decrypts instead of encrypts.
+.macro aes_decrypt data, keylen
+.if \keylen == 128
+ vaesz.vs \data, v11
+.elseif \keylen == 192
+ vaesz.vs \data, v13
+ vaesdm.vs \data, v12
+ vaesdm.vs \data, v11
+.else
+ vaesz.vs \data, v15
+ vaesdm.vs \data, v14
+ vaesdm.vs \data, v13
+ vaesdm.vs \data, v12
+ vaesdm.vs \data, v11
+.endif
+ vaesdm.vs \data, v10
+ vaesdm.vs \data, v9
+ vaesdm.vs \data, v8
+ vaesdm.vs \data, v7
+ vaesdm.vs \data, v6
+ vaesdm.vs \data, v5
+ vaesdm.vs \data, v4
+ vaesdm.vs \data, v3
+ vaesdm.vs \data, v2
+ vaesdf.vs \data, v1
+.endm
+
+// Expands to aes_encrypt or aes_decrypt according to \enc, which is 1 or 0.
+.macro aes_crypt data, enc, keylen
+.if \enc
+ aes_encrypt \data, \keylen
+.else
+ aes_decrypt \data, \keylen
+.endif
+.endm
diff --git a/arch/riscv/crypto/aes-riscv64-glue.c b/arch/riscv/crypto/aes-riscv64-glue.c
new file mode 100644
index 0000000000000..f9c7b1a638f2d
--- /dev/null
+++ b/arch/riscv/crypto/aes-riscv64-glue.c
@@ -0,0 +1,123 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AES using the RISC-V vector crypto extensions
+ *
+ * Copyright (C) 2023 VRULL GmbH
+ * Author: Heiko Stuebner <heiko.stuebner@xxxxxxxx>
+ *
+ * Copyright (C) 2023 SiFive, Inc.
+ * Author: Jerry Shih <jerry.shih@xxxxxxxxxx>
+ */
+
+#include <asm/simd.h>
+#include <asm/vector.h>
+#include <crypto/aes.h>
+#include <crypto/internal/cipher.h>
+#include <crypto/internal/simd.h>
+#include <linux/linkage.h>
+#include <linux/module.h>
+
+#include "aes-riscv64-glue.h"
+
+asmlinkage void aes_encrypt_zvkned(const struct crypto_aes_ctx *key,
+ const u8 in[AES_BLOCK_SIZE],
+ u8 out[AES_BLOCK_SIZE]);
+asmlinkage void aes_decrypt_zvkned(const struct crypto_aes_ctx *key,
+ const u8 in[AES_BLOCK_SIZE],
+ u8 out[AES_BLOCK_SIZE]);
+
+int __riscv64_aes_setkey(struct crypto_aes_ctx *ctx, const u8 *key,
+ unsigned int keylen)
+{
+ /*
+ * Always use the generic key expansion routine, for two reasons:
+ *
+ * - zvkned's key expansion instructions don't support AES-192.
+ *
+ * - ctx->key_dec always needs to be initialized with the round keys for
+ * the Equivalent Inverse Cipher, in case the no-SIMD fallback is
+ * taken during decryption. But the zvkned code does not use this.
+ */
+ return aes_expandkey(ctx, key, keylen);
+}
+EXPORT_SYMBOL_GPL(__riscv64_aes_setkey);
+
+void __riscv64_aes_encrypt(const struct crypto_aes_ctx *ctx,
+ u8 *dst, const u8 *src)
+{
+ if (crypto_simd_usable()) {
+ kernel_vector_begin();
+ aes_encrypt_zvkned(ctx, src, dst);
+ kernel_vector_end();
+ } else {
+ aes_encrypt(ctx, dst, src);
+ }
+}
+EXPORT_SYMBOL_GPL(__riscv64_aes_encrypt);
+
+static int riscv64_aes_setkey(struct crypto_tfm *tfm,
+ const u8 *key, unsigned int keylen)
+{
+ struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ return __riscv64_aes_setkey(ctx, key, keylen);
+}
+
+static void riscv64_aes_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
+{
+ const struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ __riscv64_aes_encrypt(ctx, dst, src);
+}
+
+static void riscv64_aes_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
+{
+ const struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ if (crypto_simd_usable()) {
+ kernel_vector_begin();
+ aes_decrypt_zvkned(ctx, src, dst);
+ kernel_vector_end();
+ } else {
+ aes_decrypt(ctx, dst, src);
+ }
+}
+
+static struct crypto_alg riscv64_aes_alg = {
+ .cra_flags = CRYPTO_ALG_TYPE_CIPHER,
+ .cra_blocksize = AES_BLOCK_SIZE,
+ .cra_ctxsize = sizeof(struct crypto_aes_ctx),
+ .cra_priority = 300,
+ .cra_name = "aes",
+ .cra_driver_name = "aes-riscv64-zvkned",
+ .cra_cipher = {
+ .cia_min_keysize = AES_MIN_KEY_SIZE,
+ .cia_max_keysize = AES_MAX_KEY_SIZE,
+ .cia_setkey = riscv64_aes_setkey,
+ .cia_encrypt = riscv64_aes_encrypt,
+ .cia_decrypt = riscv64_aes_decrypt,
+ },
+ .cra_module = THIS_MODULE,
+};
+
+static int __init riscv64_aes_mod_init(void)
+{
+ if (riscv_isa_extension_available(NULL, ZVKNED) &&
+ riscv_vector_vlen() >= 128)
+ return crypto_register_alg(&riscv64_aes_alg);
+
+ return -ENODEV;
+}
+
+static void __exit riscv64_aes_mod_fini(void)
+{
+ crypto_unregister_alg(&riscv64_aes_alg);
+}
+
+module_init(riscv64_aes_mod_init);
+module_exit(riscv64_aes_mod_fini);
+
+MODULE_DESCRIPTION("AES (RISC-V accelerated)");
+MODULE_AUTHOR("Heiko Stuebner <heiko.stuebner@xxxxxxxx>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_CRYPTO("aes");
diff --git a/arch/riscv/crypto/aes-riscv64-glue.h b/arch/riscv/crypto/aes-riscv64-glue.h
new file mode 100644
index 0000000000000..0d38613380784
--- /dev/null
+++ b/arch/riscv/crypto/aes-riscv64-glue.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef AES_RISCV64_GLUE_H
+#define AES_RISCV64_GLUE_H
+
+#include <crypto/aes.h>
+#include <linux/types.h>
+
+int __riscv64_aes_setkey(struct crypto_aes_ctx *ctx,
+ const u8 *key, unsigned int keylen);
+
+void __riscv64_aes_encrypt(const struct crypto_aes_ctx *ctx,
+ u8 *dst, const u8 *src);
+
+#endif /* AES_RISCV64_GLUE_H */
diff --git a/arch/riscv/crypto/aes-riscv64-zvkned.S b/arch/riscv/crypto/aes-riscv64-zvkned.S
new file mode 100644
index 0000000000000..3346978b89d6a
--- /dev/null
+++ b/arch/riscv/crypto/aes-riscv64-zvkned.S
@@ -0,0 +1,84 @@
+/* SPDX-License-Identifier: Apache-2.0 OR BSD-2-Clause */
+//
+// This file is dual-licensed, meaning that you can use it under your
+// choice of either of the following two licenses:
+//
+// Copyright 2023 The OpenSSL Project Authors. All Rights Reserved.
+//
+// Licensed under the Apache License 2.0 (the "License"). You can obtain
+// a copy in the file LICENSE in the source distribution or at
+// https://www.openssl.org/source/license.html
+//
+// or
+//
+// Copyright (c) 2023, Christoph Müllner <christoph.muellner@xxxxxxxx>
+// Copyright (c) 2023, Phoebe Chen <phoebe.chen@xxxxxxxxxx>
+// Copyright (c) 2023, Jerry Shih <jerry.shih@xxxxxxxxxx>
+// Copyright 2024 Google LLC
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions
+// are met:
+// 1. Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright
+// notice, this list of conditions and the following disclaimer in the
+// documentation and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. INP NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER INP CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING INP ANY WAY OUTP OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// The generated code of this file depends on the following RISC-V extensions:
+// - RV64I
+// - RISC-V Vector ('V') with VLEN >= 128
+// - RISC-V Vector AES block cipher extension ('Zvkned')
+
+#include <linux/linkage.h>
+
+.text
+.option arch, +zvkned
+
+#include "aes-macros.S"
+
+#define KEYP a0
+#define INP a1
+#define OUTP a2
+#define LEN a3
+#define IVP a4
+
+.macro __aes_crypt_zvkned enc, keylen
+ vle32.v v16, (INP)
+ aes_crypt v16, \enc, \keylen
+ vse32.v v16, (OUTP)
+ ret
+.endm
+
+.macro aes_crypt_zvkned enc
+ aes_begin KEYP, 111f, 222f
+ __aes_crypt_zvkned \enc, 256
+111:
+ __aes_crypt_zvkned \enc, 128
+222:
+ __aes_crypt_zvkned \enc, 192
+.endm
+
+// void aes_encrypt_zvkned(const struct crypto_aes_ctx *key,
+// const u8 in[16], u8 out[16]);
+SYM_FUNC_START(aes_encrypt_zvkned)
+ aes_crypt_zvkned 1
+SYM_FUNC_END(aes_encrypt_zvkned)
+
+// Same prototype and calling convention as the encryption function
+SYM_FUNC_START(aes_decrypt_zvkned)
+ aes_crypt_zvkned 0
+SYM_FUNC_END(aes_decrypt_zvkned)
--
2.43.0