crypto: arm - add support for SHA1 using ARMv8 Crypto Instructions

This implements the SHA1 secure hash algorithm using the AArch32
versions of the ARMv8 Crypto Extensions for SHA1.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

arch/arm/crypto/Kconfig

@@ -27,6 +27,16 @@ config CRYPTO_SHA1_ARM_NEON
 	  using optimized ARM NEON assembly, when NEON instructions are
 	  available.
 
+config CRYPTO_SHA1_ARM_CE
+	tristate "SHA1 digest algorithm (ARM v8 Crypto Extensions)"
+	depends on KERNEL_MODE_NEON
+	select CRYPTO_SHA1_ARM
+	select CRYPTO_SHA1
+	select CRYPTO_HASH
+	help
+	  SHA-1 secure hash standard (FIPS 180-1/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

@@ -7,12 +7,14 @@ obj-$(CONFIG_CRYPTO_AES_ARM_BS) += aes-arm-bs.o
 obj-$(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
 
 aes-arm-y	:= aes-armv4.o aes_glue.o
 aes-arm-bs-y	:= aesbs-core.o aesbs-glue.o
 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
 
 quiet_cmd_perl = PERL    $@
       cmd_perl = $(PERL) $(<) > $(@)

arch/arm/crypto/sha1-ce-core.S

+/*
+ * sha1-ce-core.S - SHA-1 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	q0
+	k1		.req	q1
+	k2		.req	q2
+	k3		.req	q3
+
+	ta0		.req	q4
+	ta1		.req	q5
+	tb0		.req	q5
+	tb1		.req	q4
+
+	dga		.req	q6
+	dgb		.req	q7
+	dgbs		.req	s28
+
+	dg0		.req	q12
+	dg1a0		.req	q13
+	dg1a1		.req	q14
+	dg1b0		.req	q14
+	dg1b1		.req	q13
+
+	.macro		add_only, op, ev, rc, s0, dg1
+	.ifnb		\s0
+	vadd.u32	tb\ev, q\s0, \rc
+	.endif
+	sha1h.32	dg1b\ev, dg0
+	.ifb		\dg1
+	sha1\op\().32	dg0, dg1a\ev, ta\ev
+	.else
+	sha1\op\().32	dg0, \dg1, ta\ev
+	.endif
+	.endm
+
+	.macro		add_update, op, ev, rc, s0, s1, s2, s3, dg1
+	sha1su0.32	q\s0, q\s1, q\s2
+	add_only	\op, \ev, \rc, \s1, \dg1
+	sha1su1.32	q\s0, q\s3
+	.endm
+
+	.align		6
+.Lsha1_rcon:
+	.word		0x5a827999, 0x5a827999, 0x5a827999, 0x5a827999
+	.word		0x6ed9eba1, 0x6ed9eba1, 0x6ed9eba1, 0x6ed9eba1
+	.word		0x8f1bbcdc, 0x8f1bbcdc, 0x8f1bbcdc, 0x8f1bbcdc
+	.word		0xca62c1d6, 0xca62c1d6, 0xca62c1d6, 0xca62c1d6
+
+	/*
+	 * void sha1_ce_transform(int blocks, u8 const *src, u32 *state,
+	 *			  u8 *head);
+	 */
+ENTRY(sha1_ce_transform)
+	/* load round constants */
+	adr		ip, .Lsha1_rcon
+	vld1.32		{k0-k1}, [ip, :128]!
+	vld1.32		{k2-k3}, [ip, :128]
+
+	/* load state */
+	vld1.32		{dga}, [r2]
+	vldr		dgbs, [r2, #16]
+
+	/* load partial input (if supplied) */
+	teq		r3, #0
+	beq		0f
+	vld1.32		{q8-q9}, [r3]!
+	vld1.32		{q10-q11}, [r3]
+	teq		r0, #0
+	b		1f
+
+	/* load input */
+0:	vld1.32		{q8-q9}, [r1]!
+	vld1.32		{q10-q11}, [r1]!
+	subs		r0, r0, #1
+
+1:
+#ifndef CONFIG_CPU_BIG_ENDIAN
+	vrev32.8	q8, q8
+	vrev32.8	q9, q9
+	vrev32.8	q10, q10
+	vrev32.8	q11, q11
+#endif
+
+	vadd.u32	ta0, q8, k0
+	vmov		dg0, dga
+
+	add_update	c, 0, k0,  8,  9, 10, 11, dgb
+	add_update	c, 1, k0,  9, 10, 11,  8
+	add_update	c, 0, k0, 10, 11,  8,  9
+	add_update	c, 1, k0, 11,  8,  9, 10
+	add_update	c, 0, k1,  8,  9, 10, 11
+
+	add_update	p, 1, k1,  9, 10, 11,  8
+	add_update	p, 0, k1, 10, 11,  8,  9
+	add_update	p, 1, k1, 11,  8,  9, 10
+	add_update	p, 0, k1,  8,  9, 10, 11
+	add_update	p, 1, k2,  9, 10, 11,  8
+
+	add_update	m, 0, k2, 10, 11,  8,  9
+	add_update	m, 1, k2, 11,  8,  9, 10
+	add_update	m, 0, k2,  8,  9, 10, 11
+	add_update	m, 1, k2,  9, 10, 11,  8
+	add_update	m, 0, k3, 10, 11,  8,  9
+
+	add_update	p, 1, k3, 11,  8,  9, 10
+	add_only	p, 0, k3,  9
+	add_only	p, 1, k3, 10
+	add_only	p, 0, k3, 11
+	add_only	p, 1
+
+	/* update state */
+	vadd.u32	dga, dga, dg0
+	vadd.u32	dgb, dgb, dg1a0
+	bne		0b
+
+	/* store new state */
+	vst1.32		{dga}, [r2]
+	vstr		dgbs, [r2, #16]
+	bx		lr
+ENDPROC(sha1_ce_transform)

arch/arm/crypto/sha1-ce-glue.c

+/*
+ * sha1-ce-glue.c - SHA-1 secure hash 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/crypto/sha1.h>
+#include <asm/hwcap.h>
+#include <asm/neon.h>
+#include <asm/simd.h>
+#include <asm/unaligned.h>
+
+MODULE_DESCRIPTION("SHA1 secure hash using ARMv8 Crypto Extensions");
+MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
+MODULE_LICENSE("GPL v2");
+
+asmlinkage void sha1_ce_transform(int blocks, u8 const *src, u32 *state, 
+				  u8 *head);
+
+static int sha1_init(struct shash_desc *desc)
+{
+	struct sha1_state *sctx = shash_desc_ctx(desc);
+
+	*sctx = (struct sha1_state){
+		.state = { SHA1_H0, SHA1_H1, SHA1_H2, SHA1_H3, SHA1_H4 },
+	};
+	return 0;
+}
+
+static int sha1_update(struct shash_desc *desc, const u8 *data,
+		       unsigned int len)
+{
+	struct sha1_state *sctx = shash_desc_ctx(desc);
+	unsigned int partial;
+
+	if (!may_use_simd())
+		return sha1_update_arm(desc, data, len);
+
+	partial = sctx->count % SHA1_BLOCK_SIZE;
+	sctx->count += len;
+
+	if ((partial + len) >= SHA1_BLOCK_SIZE) {
+		int blocks;
+
+		if (partial) {
+			int p = SHA1_BLOCK_SIZE - partial;
+
+			memcpy(sctx->buffer + partial, data, p);
+			data += p;
+			len -= p;
+		}
+
+		blocks = len / SHA1_BLOCK_SIZE;
+		len %= SHA1_BLOCK_SIZE;
+
+		kernel_neon_begin();
+		sha1_ce_transform(blocks, data, sctx->state,
+				  partial ? sctx->buffer : NULL);
+		kernel_neon_end();
+
+		data += blocks * SHA1_BLOCK_SIZE;
+		partial = 0;
+	}
+	if (len)
+		memcpy(sctx->buffer + partial, data, len);
+	return 0;
+}
+
+static int sha1_final(struct shash_desc *desc, u8 *out)
+{
+	static const u8 padding[SHA1_BLOCK_SIZE] = { 0x80, };
+
+	struct sha1_state *sctx = shash_desc_ctx(desc);
+	__be64 bits = cpu_to_be64(sctx->count << 3);
+	__be32 *dst = (__be32 *)out;
+	int i;
+
+	u32 padlen = SHA1_BLOCK_SIZE
+		     - ((sctx->count + sizeof(bits)) % SHA1_BLOCK_SIZE);
+
+	sha1_update(desc, padding, padlen);
+	sha1_update(desc, (const u8 *)&bits, sizeof(bits));
+
+	for (i = 0; i < SHA1_DIGEST_SIZE / sizeof(__be32); i++)
+		put_unaligned_be32(sctx->state[i], dst++);
+
+	*sctx = (struct sha1_state){};
+	return 0;
+}
+
+static int sha1_export(struct shash_desc *desc, void *out)
+{
+	struct sha1_state *sctx = shash_desc_ctx(desc);
+	struct sha1_state *dst = out;
+
+	*dst = *sctx;
+	return 0;
+}
+
+static int sha1_import(struct shash_desc *desc, const void *in)
+{
+	struct sha1_state *sctx = shash_desc_ctx(desc);
+	struct sha1_state const *src = in;
+
+	*sctx = *src;
+	return 0;
+}
+
+static struct shash_alg alg = {
+	.init			= sha1_init,
+	.update			= sha1_update,
+	.final			= sha1_final,
+	.export			= sha1_export,
+	.import			= sha1_import,
+	.descsize		= sizeof(struct sha1_state),
+	.digestsize		= SHA1_DIGEST_SIZE,
+	.statesize		= sizeof(struct sha1_state),
+	.base			= {
+		.cra_name		= "sha1",
+		.cra_driver_name	= "sha1-ce",
+		.cra_priority		= 200,
+		.cra_flags		= CRYPTO_ALG_TYPE_SHASH,
+		.cra_blocksize		= SHA1_BLOCK_SIZE,
+		.cra_module		= THIS_MODULE,
+	}
+};
+
+static int __init sha1_ce_mod_init(void)
+{
+	if (!(elf_hwcap2 & HWCAP2_SHA1))
+		return -ENODEV;
+	return crypto_register_shash(&alg);
+}
+
+static void __exit sha1_ce_mod_fini(void)
+{
+	crypto_unregister_shash(&alg);
+}
+
+module_init(sha1_ce_mod_init);
+module_exit(sha1_ce_mod_fini);