crypto: arm - add support for SHA-224/256 using ARMv8 Crypto Extensions

This implements the SHA-224/256 secure hash algorithm using the AArch32
versions of the ARMv8 Crypto Extensions for SHA2.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

arch/arm/crypto/Kconfig

@@ -37,6 +37,15 @@ config CRYPTO_SHA1_ARM_CE
 	  SHA-1 secure hash standard (FIPS 180-1/DFIPS 180-2) implemented
 	  using special ARMv8 Crypto Extensions.
 
+config CRYPTO_SHA2_ARM_CE
+	tristate "SHA-224/256 digest algorithm (ARM v8 Crypto Extensions)"
+	depends on KERNEL_MODE_NEON
+	select CRYPTO_SHA256
+	select CRYPTO_HASH
+	help
+	  SHA-256 secure hash standard (DFIPS 180-2) implemented
+	  using special ARMv8 Crypto Extensions.
+
 config CRYPTO_SHA512_ARM_NEON
 	tristate "SHA384 and SHA512 digest algorithm (ARM NEON)"
 	depends on KERNEL_MODE_NEON

arch/arm/crypto/Makefile

@@ -8,6 +8,7 @@ obj-$(CONFIG_CRYPTO_SHA1_ARM) += sha1-arm.o
 obj-$(CONFIG_CRYPTO_SHA1_ARM_NEON) += sha1-arm-neon.o
 obj-$(CONFIG_CRYPTO_SHA512_ARM_NEON) += sha512-arm-neon.o
 obj-$(CONFIG_CRYPTO_SHA1_ARM_CE) += sha1-arm-ce.o
+obj-$(CONFIG_CRYPTO_SHA2_ARM_CE) += sha2-arm-ce.o
 
 aes-arm-y	:= aes-armv4.o aes_glue.o
 aes-arm-bs-y	:= aesbs-core.o aesbs-glue.o
@@ -15,6 +16,7 @@ sha1-arm-y	:= sha1-armv4-large.o sha1_glue.o
 sha1-arm-neon-y	:= sha1-armv7-neon.o sha1_neon_glue.o
 sha512-arm-neon-y := sha512-armv7-neon.o sha512_neon_glue.o
 sha1-arm-ce-y	:= sha1-ce-core.o sha1-ce-glue.o
+sha2-arm-ce-y	:= sha2-ce-core.o sha2-ce-glue.o
 
 quiet_cmd_perl = PERL    $@
       cmd_perl = $(PERL) $(<) > $(@)

arch/arm/crypto/sha2-ce-core.S

+/*
+ * sha2-ce-core.S - SHA-224/256 secure hash using ARMv8 Crypto Extensions
+ *
+ * Copyright (C) 2015 Linaro Ltd.
+ * Author: Ard Biesheuvel <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 <linux/linkage.h>
+#include <asm/assembler.h>
+
+	.text
+	.fpu		crypto-neon-fp-armv8
+
+	k0		.req	q7
+	k1		.req	q8
+	rk		.req	r3
+
+	ta0		.req	q9
+	ta1		.req	q10
+	tb0		.req	q10
+	tb1		.req	q9
+
+	dga		.req	q11
+	dgb		.req	q12
+
+	dg0		.req	q13
+	dg1		.req	q14
+	dg2		.req	q15
+
+	.macro		add_only, ev, s0
+	vmov		dg2, dg0
+	.ifnb		\s0
+	vld1.32		{k\ev}, [rk, :128]!
+	.endif
+	sha256h.32	dg0, dg1, tb\ev
+	sha256h2.32	dg1, dg2, tb\ev
+	.ifnb		\s0
+	vadd.u32	ta\ev, q\s0, k\ev
+	.endif
+	.endm
+
+	.macro		add_update, ev, s0, s1, s2, s3
+	sha256su0.32	q\s0, q\s1
+	add_only	\ev, \s1
+	sha256su1.32	q\s0, q\s2, q\s3
+	.endm
+
+	.align		6
+.Lsha256_rcon:
+	.word		0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5
+	.word		0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5
+	.word		0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3
+	.word		0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174
+	.word		0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc
+	.word		0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da
+	.word		0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7
+	.word		0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967
+	.word		0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13
+	.word		0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85
+	.word		0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3
+	.word		0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070
+	.word		0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5
+	.word		0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3
+	.word		0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208
+	.word		0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
+
+	/*
+	 * void sha2_ce_transform(int blocks, u8 const *src, u32 *state,
+	 *			  u8 *head);
+	 */
+ENTRY(sha2_ce_transform)
+	/* load state */
+	vld1.32		{dga-dgb}, [r2]
+
+	/* load partial input (if supplied) */
+	teq		r3, #0
+	beq		0f
+	vld1.32		{q0-q1}, [r3]!
+	vld1.32		{q2-q3}, [r3]
+	teq		r0, #0
+	b		1f
+
+	/* load input */
+0:	vld1.32		{q0-q1}, [r1]!
+	vld1.32		{q2-q3}, [r1]!
+	subs		r0, r0, #1
+
+1:
+#ifndef CONFIG_CPU_BIG_ENDIAN
+	vrev32.8	q0, q0
+	vrev32.8	q1, q1
+	vrev32.8	q2, q2
+	vrev32.8	q3, q3
+#endif
+
+	/* load first round constant */
+	adr		rk, .Lsha256_rcon
+	vld1.32		{k0}, [rk, :128]!
+
+	vadd.u32	ta0, q0, k0
+	vmov		dg0, dga
+	vmov		dg1, dgb
+
+	add_update	1, 0, 1, 2, 3
+	add_update	0, 1, 2, 3, 0
+	add_update	1, 2, 3, 0, 1
+	add_update	0, 3, 0, 1, 2
+	add_update	1, 0, 1, 2, 3
+	add_update	0, 1, 2, 3, 0
+	add_update	1, 2, 3, 0, 1
+	add_update	0, 3, 0, 1, 2
+	add_update	1, 0, 1, 2, 3
+	add_update	0, 1, 2, 3, 0
+	add_update	1, 2, 3, 0, 1
+	add_update	0, 3, 0, 1, 2
+
+	add_only	1, 1
+	add_only	0, 2
+	add_only	1, 3
+	add_only	0
+
+	/* update state */
+	vadd.u32	dga, dga, dg0
+	vadd.u32	dgb, dgb, dg1
+	bne		0b
+
+	/* store new state */
+	vst1.32		{dga-dgb}, [r2]
+	bx		lr
+ENDPROC(sha2_ce_transform)

arch/arm/crypto/sha2-ce-glue.c

+/*
+ * sha2-ce-glue.c - SHA-224/SHA-256 using ARMv8 Crypto Extensions
+ *
+ * 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 <crypto/internal/hash.h>
+#include <crypto/sha.h>
+#include <linux/crypto.h>
+#include <linux/module.h>
+
+#include <asm/hwcap.h>
+#include <asm/simd.h>
+#include <asm/neon.h>
+#include <asm/unaligned.h>
+
+MODULE_DESCRIPTION("SHA-224/SHA-256 secure hash using ARMv8 Crypto Extensions");
+MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
+MODULE_LICENSE("GPL v2");
+
+asmlinkage void sha2_ce_transform(int blocks, u8 const *src, u32 *state,
+				  u8 *head);
+
+static int sha224_init(struct shash_desc *desc)
+{
+	struct sha256_state *sctx = shash_desc_ctx(desc);
+
+	*sctx = (struct sha256_state){
+		.state = {
+			SHA224_H0, SHA224_H1, SHA224_H2, SHA224_H3,
+			SHA224_H4, SHA224_H5, SHA224_H6, SHA224_H7,
+		}
+	};
+	return 0;
+}
+
+static int sha256_init(struct shash_desc *desc)
+{
+	struct sha256_state *sctx = shash_desc_ctx(desc);
+
+	*sctx = (struct sha256_state){
+		.state = {
+			SHA256_H0, SHA256_H1, SHA256_H2, SHA256_H3,
+			SHA256_H4, SHA256_H5, SHA256_H6, SHA256_H7,
+		}
+	};
+	return 0;
+}
+
+static int sha2_update(struct shash_desc *desc, const u8 *data,
+		       unsigned int len)
+{
+	struct sha256_state *sctx = shash_desc_ctx(desc);
+	unsigned int partial;
+
+	if (!may_use_simd())
+		return crypto_sha256_update(desc, data, len);
+
+	partial = sctx->count % SHA256_BLOCK_SIZE;
+	sctx->count += len;
+
+	if ((partial + len) >= SHA256_BLOCK_SIZE) {
+		int blocks;
+
+		if (partial) {
+			int p = SHA256_BLOCK_SIZE - partial;
+
+			memcpy(sctx->buf + partial, data, p);
+			data += p;
+			len -= p;
+		}
+
+		blocks = len / SHA256_BLOCK_SIZE;
+		len %= SHA256_BLOCK_SIZE;
+
+		kernel_neon_begin();
+		sha2_ce_transform(blocks, data, sctx->state,
+				  partial ? sctx->buf : NULL);
+		kernel_neon_end();
+
+		data += blocks * SHA256_BLOCK_SIZE;
+		partial = 0;
+	}
+	if (len)
+		memcpy(sctx->buf + partial, data, len);
+	return 0;
+}
+
+static void sha2_final(struct shash_desc *desc)
+{
+	static const u8 padding[SHA256_BLOCK_SIZE] = { 0x80, };
+
+	struct sha256_state *sctx = shash_desc_ctx(desc);
+	__be64 bits = cpu_to_be64(sctx->count << 3);
+	u32 padlen = SHA256_BLOCK_SIZE
+		     - ((sctx->count + sizeof(bits)) % SHA256_BLOCK_SIZE);
+
+	sha2_update(desc, padding, padlen);
+	sha2_update(desc, (const u8 *)&bits, sizeof(bits));
+}
+
+static int sha224_final(struct shash_desc *desc, u8 *out)
+{
+	struct sha256_state *sctx = shash_desc_ctx(desc);
+	__be32 *dst = (__be32 *)out;
+	int i;
+
+	sha2_final(desc);
+
+	for (i = 0; i < SHA224_DIGEST_SIZE / sizeof(__be32); i++)
+		put_unaligned_be32(sctx->state[i], dst++);
+
+	*sctx = (struct sha256_state){};
+	return 0;
+}
+
+static int sha256_final(struct shash_desc *desc, u8 *out)
+{
+	struct sha256_state *sctx = shash_desc_ctx(desc);
+	__be32 *dst = (__be32 *)out;
+	int i;
+
+	sha2_final(desc);
+
+	for (i = 0; i < SHA256_DIGEST_SIZE / sizeof(__be32); i++)
+		put_unaligned_be32(sctx->state[i], dst++);
+
+	*sctx = (struct sha256_state){};
+	return 0;
+}
+
+static int sha2_export(struct shash_desc *desc, void *out)
+{
+	struct sha256_state *sctx = shash_desc_ctx(desc);
+	struct sha256_state *dst = out;
+
+	*dst = *sctx;
+	return 0;
+}
+
+static int sha2_import(struct shash_desc *desc, const void *in)
+{
+	struct sha256_state *sctx = shash_desc_ctx(desc);
+	struct sha256_state const *src = in;
+
+	*sctx = *src;
+	return 0;
+}
+
+static struct shash_alg algs[] = { {
+	.init			= sha224_init,
+	.update			= sha2_update,
+	.final			= sha224_final,
+	.export			= sha2_export,
+	.import			= sha2_import,
+	.descsize		= sizeof(struct sha256_state),
+	.digestsize		= SHA224_DIGEST_SIZE,
+	.statesize		= sizeof(struct sha256_state),
+	.base			= {
+		.cra_name		= "sha224",
+		.cra_driver_name	= "sha224-ce",
+		.cra_priority		= 200,
+		.cra_flags		= CRYPTO_ALG_TYPE_SHASH,
+		.cra_blocksize		= SHA256_BLOCK_SIZE,
+		.cra_module		= THIS_MODULE,
+	}
+}, {
+	.init			= sha256_init,
+	.update			= sha2_update,
+	.final			= sha256_final,
+	.export			= sha2_export,
+	.import			= sha2_import,
+	.descsize		= sizeof(struct sha256_state),
+	.digestsize		= SHA256_DIGEST_SIZE,
+	.statesize		= sizeof(struct sha256_state),
+	.base			= {
+		.cra_name		= "sha256",
+		.cra_driver_name	= "sha256-ce",
+		.cra_priority		= 200,
+		.cra_flags		= CRYPTO_ALG_TYPE_SHASH,
+		.cra_blocksize		= SHA256_BLOCK_SIZE,
+		.cra_module		= THIS_MODULE,
+	}
+} };
+
+static int __init sha2_ce_mod_init(void)
+{
+	if (!(elf_hwcap2 & HWCAP2_SHA2))
+		return -ENODEV;
+	return crypto_register_shashes(algs, ARRAY_SIZE(algs));
+}
+
+static void __exit sha2_ce_mod_fini(void)
+{
+	crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
+}
+
+module_init(sha2_ce_mod_init);
+module_exit(sha2_ce_mod_fini);