[RFT] crypto: arm/aes - replace scalar AES cipher

diff --git a/arch/arm/crypto/Kconfig b/arch/arm/crypto/Kconfig
index 2f3339f015d3..f1de658c3c8f 100644
--- a/arch/arm/crypto/Kconfig
+++ b/arch/arm/crypto/Kconfig
@@ -62,33 +62,15 @@  config CRYPTO_SHA512_ARM
 	  using optimized ARM assembler and NEON, when available.
 
 config CRYPTO_AES_ARM
-	tristate "AES cipher algorithms (ARM-asm)"
-	depends on ARM
+	tristate "Scalar AES cipher for ARM"
 	select CRYPTO_ALGAPI
 	select CRYPTO_AES
 	help
 	  Use optimized AES assembler routines for ARM platforms.
 
-	  AES cipher algorithms (FIPS-197). AES uses the Rijndael
-	  algorithm.
-
-	  Rijndael appears to be consistently a very good performer in
-	  both hardware and software across a wide range of computing
-	  environments regardless of its use in feedback or non-feedback
-	  modes. Its key setup time is excellent, and its key agility is
-	  good. Rijndael's very low memory requirements make it very well
-	  suited for restricted-space environments, in which it also
-	  demonstrates excellent performance. Rijndael's operations are
-	  among the easiest to defend against power and timing attacks.
-
-	  The AES specifies three key sizes: 128, 192 and 256 bits
-
-	  See <http://csrc.nist.gov/encryption/aes/> for more information.
-
 config CRYPTO_AES_ARM_BS
 	tristate "Bit sliced AES using NEON instructions"
 	depends on KERNEL_MODE_NEON
-	select CRYPTO_AES_ARM
 	select CRYPTO_BLKCIPHER
 	select CRYPTO_SIMD
 	help
diff --git a/arch/arm/crypto/Makefile b/arch/arm/crypto/Makefile
index 8d74e55eacd4..8f5de2db701c 100644
--- a/arch/arm/crypto/Makefile
+++ b/arch/arm/crypto/Makefile
@@ -27,8 +27,8 @@  $(warning $(ce-obj-y) $(ce-obj-m))
 endif
 endif
 
-aes-arm-y	:= aes-armv4.o aes_glue.o
-aes-arm-bs-y	:= aesbs-core.o aesbs-glue.o
+aes-arm-y	:= aes-cipher-core.o aes-cipher-glue.o
+aes-arm-bs-y	:= aes-armv4.o 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
 sha256-arm-neon-$(CONFIG_KERNEL_MODE_NEON) := sha256_neon_glue.o
diff --git a/arch/arm/crypto/aes-cipher-core.S b/arch/arm/crypto/aes-cipher-core.S
new file mode 100644
index 000000000000..8d4a15364d43
--- /dev/null
+++ b/arch/arm/crypto/aes-cipher-core.S
@@ -0,0 +1,169 @@ 
+/*
+ * Scalar AES core transform
+ *
+ * Copyright (C) 2017 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 <linux/linkage.h>
+
+	.text
+	.align		5
+
+	rk		.req	r0
+	rounds		.req	r1
+	in		.req	r2
+	out		.req	r3
+	tt		.req	ip
+
+	t0		.req	lr
+	t1		.req	r2
+	t2		.req	r3
+
+	.macro		__select, out, in, idx
+	.if		__LINUX_ARM_ARCH__ < 7
+	and		\out, \in, #0xff << (8 * \idx)
+	.else
+	ubfx		\out, \in, #(8 * \idx), #8
+	.endif
+	.endm
+
+	.macro		__load, out, in, idx
+	.if		__LINUX_ARM_ARCH__ < 7 && \idx > 0
+	ldr		\out, [tt, \in, lsr #(8 * \idx) - 2]
+	.else
+	ldr		\out, [tt, \in, lsl #2]
+	.endif
+	.endm
+
+	.macro		__hround, out0, out1, in0, in1, in2, in3, t3, t4, enc
+	__select	\out0, \in0, 0
+	__select	t0, \in1, 1
+	__load		\out0, \out0, 0
+	__load		t0, t0, 1
+
+	.if		\enc
+	__select	\out1, \in1, 0
+	__select	t1, \in2, 1
+	.else
+	__select	\out1, \in3, 0
+	__select	t1, \in0, 1
+	.endif
+	__load		\out1, \out1, 0
+	__select	t2, \in2, 2
+	__load		t1, t1, 1
+	__load		t2, t2, 2
+
+	eor		\out0, \out0, t0, ror #24
+
+	__select	t0, \in3, 3
+	.if		\enc
+	__select	\t3, \in3, 2
+	__select	\t4, \in0, 3
+	.else
+	__select	\t3, \in1, 2
+	__select	\t4, \in2, 3
+	.endif
+	__load		\t3, \t3, 2
+	__load		t0, t0, 3
+	__load		\t4, \t4, 3
+
+	eor		\out1, \out1, t1, ror #24
+	eor		\out0, \out0, t2, ror #16
+	ldm		rk!, {t1, t2}
+	eor		\out1, \out1, \t3, ror #16
+	eor		\out0, \out0, t0, ror #8
+	eor		\out1, \out1, \t4, ror #8
+	eor		\out0, \out0, t1
+	eor		\out1, \out1, t2
+	.endm
+
+	.macro		fround, out0, out1, out2, out3, in0, in1, in2, in3
+	__hround	\out0, \out1, \in0, \in1, \in2, \in3, \out2, \out3, 1
+	__hround	\out2, \out3, \in2, \in3, \in0, \in1, \in1, \in2, 1
+	.endm
+
+	.macro		iround, out0, out1, out2, out3, in0, in1, in2, in3
+	__hround	\out0, \out1, \in0, \in3, \in2, \in1, \out2, \out3, 0
+	__hround	\out2, \out3, \in2, \in1, \in0, \in3, \in1, \in0, 0
+	.endm
+
+	.macro		__rev, out, in
+	.if		__LINUX_ARM_ARCH__ < 7
+	lsl		t0, \in, #24
+	and		t1, \in, #0xff00
+	and		t2, \in, #0xff0000
+	orr		\out, t0, \in, lsr #24
+	orr		\out, \out, t1, lsl #8
+	orr		\out, \out, t2, lsr #8
+	.else
+	rev		\out, \in
+	.endif
+	.endm
+
+	.macro		do_crypt, round, ttab, ltab
+	push		{r3-r11, lr}
+
+	ldr		r4, [in]
+	ldr		r5, [in, #4]
+	ldr		r6, [in, #8]
+	ldr		r7, [in, #12]
+
+	ldm		rk!, {r8, r9, r10, r11}
+
+#ifdef CONFIG_CPU_BIG_ENDIAN
+	__rev		r4, r4
+	__rev		r5, r5
+	__rev		r6, r6
+	__rev		r7, r7
+#endif
+
+	eor		r4, r4, r8
+	eor		r5, r5, r9
+	eor		r6, r6, r10
+	eor		r7, r7, r11
+
+	ldr		tt, =\ttab
+
+	tst		rounds, #2
+	bne		1f
+
+0:	\round		r8, r9, r10, r11, r4, r5, r6, r7
+	\round		r4, r5, r6, r7, r8, r9, r10, r11
+
+1:	subs		rounds, rounds, #4
+	\round		r8, r9, r10, r11, r4, r5, r6, r7
+	ldrls		tt, =\ltab
+	\round		r4, r5, r6, r7, r8, r9, r10, r11
+	bhi		0b
+
+#ifdef CONFIG_CPU_BIG_ENDIAN
+	__rev		r4, r4
+	__rev		r5, r5
+	__rev		r6, r6
+	__rev		r7, r7
+#endif
+
+	ldr		out, [sp]
+
+	str		r4, [out]
+	str		r5, [out, #4]
+	str		r6, [out, #8]
+	str		r7, [out, #12]
+
+	pop		{r3-r11, pc}
+
+	.align		3
+	.ltorg
+	.endm
+
+ENTRY(__aes_arm_encrypt)
+	do_crypt	fround, crypto_ft_tab, crypto_fl_tab
+ENDPROC(__aes_arm_encrypt)
+
+ENTRY(__aes_arm_decrypt)
+	do_crypt	iround, crypto_it_tab, crypto_il_tab
+ENDPROC(__aes_arm_decrypt)
diff --git a/arch/arm/crypto/aes-cipher-glue.c b/arch/arm/crypto/aes-cipher-glue.c
new file mode 100644
index 000000000000..19545237112a
--- /dev/null
+++ b/arch/arm/crypto/aes-cipher-glue.c
@@ -0,0 +1,69 @@ 
+/*
+ * Scalar AES core transform
+ *
+ * Copyright (C) 2017 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/aes.h>
+#include <linux/crypto.h>
+#include <linux/module.h>
+
+asmlinkage void __aes_arm_encrypt(u32 *rk, int rounds, const u8 *in, u8 *out);
+EXPORT_SYMBOL(__aes_arm_encrypt);
+
+asmlinkage void __aes_arm_decrypt(u32 *rk, int rounds, const u8 *in, u8 *out);
+EXPORT_SYMBOL(__aes_arm_decrypt);
+
+static void aes_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
+{
+	struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm);
+	int rounds = 6 + ctx->key_length / 4;
+
+	__aes_arm_encrypt(ctx->key_enc, rounds, in, out);
+}
+
+static void aes_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
+{
+	struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm);
+	int rounds = 6 + ctx->key_length / 4;
+
+	__aes_arm_decrypt(ctx->key_dec, rounds, in, out);
+}
+
+static struct crypto_alg aes_alg = {
+	.cra_name			= "aes",
+	.cra_driver_name		= "aes-arm",
+	.cra_priority			= 200,
+	.cra_flags			= CRYPTO_ALG_TYPE_CIPHER,
+	.cra_blocksize			= AES_BLOCK_SIZE,
+	.cra_ctxsize			= sizeof(struct crypto_aes_ctx),
+	.cra_module			= THIS_MODULE,
+
+	.cra_cipher.cia_min_keysize	= AES_MIN_KEY_SIZE,
+	.cra_cipher.cia_max_keysize	= AES_MAX_KEY_SIZE,
+	.cra_cipher.cia_setkey		= crypto_aes_set_key,
+	.cra_cipher.cia_encrypt		= aes_encrypt,
+	.cra_cipher.cia_decrypt		= aes_decrypt
+};
+
+static int __init aes_init(void)
+{
+	return crypto_register_alg(&aes_alg);
+}
+
+static void __exit aes_fini(void)
+{
+	crypto_unregister_alg(&aes_alg);
+}
+
+module_init(aes_init);
+module_exit(aes_fini);
+
+MODULE_DESCRIPTION("Scalar AES cipher for ARM");
+MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS_CRYPTO("aes");
diff --git a/arch/arm/crypto/aes_glue.c b/arch/arm/crypto/aes_glue.c
deleted file mode 100644
index 0409b8f89782..000000000000
--- a/arch/arm/crypto/aes_glue.c
+++ /dev/null
@@ -1,98 +0,0 @@ 
-/*
- * Glue Code for the asm optimized version of the AES Cipher Algorithm
- */
-
-#include <linux/module.h>
-#include <linux/crypto.h>
-#include <crypto/aes.h>
-
-#include "aes_glue.h"
-
-EXPORT_SYMBOL(AES_encrypt);
-EXPORT_SYMBOL(AES_decrypt);
-EXPORT_SYMBOL(private_AES_set_encrypt_key);
-EXPORT_SYMBOL(private_AES_set_decrypt_key);
-
-static void aes_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
-{
-	struct AES_CTX *ctx = crypto_tfm_ctx(tfm);
-	AES_encrypt(src, dst, &ctx->enc_key);
-}
-
-static void aes_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
-{
-	struct AES_CTX *ctx = crypto_tfm_ctx(tfm);
-	AES_decrypt(src, dst, &ctx->dec_key);
-}
-
-static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
-		unsigned int key_len)
-{
-	struct AES_CTX *ctx = crypto_tfm_ctx(tfm);
-
-	switch (key_len) {
-	case AES_KEYSIZE_128:
-		key_len = 128;
-		break;
-	case AES_KEYSIZE_192:
-		key_len = 192;
-		break;
-	case AES_KEYSIZE_256:
-		key_len = 256;
-		break;
-	default:
-		tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
-		return -EINVAL;
-	}
-
-	if (private_AES_set_encrypt_key(in_key, key_len, &ctx->enc_key) == -1) {
-		tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
-		return -EINVAL;
-	}
-	/* private_AES_set_decrypt_key expects an encryption key as input */
-	ctx->dec_key = ctx->enc_key;
-	if (private_AES_set_decrypt_key(in_key, key_len, &ctx->dec_key) == -1) {
-		tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
-		return -EINVAL;
-	}
-	return 0;
-}
-
-static struct crypto_alg aes_alg = {
-	.cra_name		= "aes",
-	.cra_driver_name	= "aes-asm",
-	.cra_priority		= 200,
-	.cra_flags		= CRYPTO_ALG_TYPE_CIPHER,
-	.cra_blocksize		= AES_BLOCK_SIZE,
-	.cra_ctxsize		= sizeof(struct AES_CTX),
-	.cra_module		= THIS_MODULE,
-	.cra_list		= LIST_HEAD_INIT(aes_alg.cra_list),
-	.cra_u	= {
-		.cipher	= {
-			.cia_min_keysize	= AES_MIN_KEY_SIZE,
-			.cia_max_keysize	= AES_MAX_KEY_SIZE,
-			.cia_setkey		= aes_set_key,
-			.cia_encrypt		= aes_encrypt,
-			.cia_decrypt		= aes_decrypt
-		}
-	}
-};
-
-static int __init aes_init(void)
-{
-	return crypto_register_alg(&aes_alg);
-}
-
-static void __exit aes_fini(void)
-{
-	crypto_unregister_alg(&aes_alg);
-}
-
-module_init(aes_init);
-module_exit(aes_fini);
-
-MODULE_DESCRIPTION("Rijndael (AES) Cipher Algorithm (ASM)");
-MODULE_LICENSE("GPL");
-MODULE_ALIAS_CRYPTO("aes");
-MODULE_ALIAS_CRYPTO("aes-asm");
-MODULE_AUTHOR("David McCullough <ucdevel@gmail.com>");