/*
 * AES-NI + SSE2 implementation of AEGIS-128L
 *
 * Copyright (c) 2017-2018 Ondrej Mosnacek <omosnacek@gmail.com>
 * Copyright (C) 2017-2018 Red Hat, Inc. All rights reserved.
 *
 * 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/frame.h>

#define STATE0	%xmm0
#define STATE1	%xmm1
#define STATE2	%xmm2
#define STATE3	%xmm3
#define STATE4	%xmm4
#define STATE5	%xmm5
#define STATE6	%xmm6
#define STATE7	%xmm7
#define MSG0	%xmm8
#define MSG1	%xmm9
#define T0	%xmm10
#define T1	%xmm11
#define T2	%xmm12
#define T3	%xmm13

#define STATEP	%rdi
#define LEN	%rsi
#define SRC	%rdx
#define DST	%rcx

.section .rodata.cst16.aegis128l_const, "aM", @progbits, 32
.align 16
.Laegis128l_const_0:
	.byte 0x00, 0x01, 0x01, 0x02, 0x03, 0x05, 0x08, 0x0d
	.byte 0x15, 0x22, 0x37, 0x59, 0x90, 0xe9, 0x79, 0x62
.Laegis128l_const_1:
	.byte 0xdb, 0x3d, 0x18, 0x55, 0x6d, 0xc2, 0x2f, 0xf1
	.byte 0x20, 0x11, 0x31, 0x42, 0x73, 0xb5, 0x28, 0xdd

.section .rodata.cst16.aegis128l_counter, "aM", @progbits, 16
.align 16
.Laegis128l_counter0:
	.byte 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07
	.byte 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f
.Laegis128l_counter1:
	.byte 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17
	.byte 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f

.text

/*
 * __load_partial: internal ABI
 * input:
 *   LEN - bytes
 *   SRC - src
 * output:
 *   MSG0 - first message block
 *   MSG1 - second message block
 * changed:
 *   T0
 *   %r8
 *   %r9
 */
__load_partial:
	xor %r9d, %r9d
	pxor MSG0, MSG0
	pxor MSG1, MSG1

	mov LEN, %r8
	and $0x1, %r8
	jz .Lld_partial_1

	mov LEN, %r8
	and $0x1E, %r8
	add SRC, %r8
	mov (%r8), %r9b

.Lld_partial_1:
	mov LEN, %r8
	and $0x2, %r8
	jz .Lld_partial_2

	mov LEN, %r8
	and $0x1C, %r8
	add SRC, %r8
	shl $0x10, %r9
	mov (%r8), %r9w

.Lld_partial_2:
	mov LEN, %r8
	and $0x4, %r8
	jz .Lld_partial_4

	mov LEN, %r8
	and $0x18, %r8
	add SRC, %r8
	shl $32, %r9
	mov (%r8), %r8d
	xor %r8, %r9

.Lld_partial_4:
	movq %r9, MSG0

	mov LEN, %r8
	and $0x8, %r8
	jz .Lld_partial_8

	mov LEN, %r8
	and $0x10, %r8
	add SRC, %r8
	pslldq $8, MSG0
	movq (%r8), T0
	pxor T0, MSG0

.Lld_partial_8:
	mov LEN, %r8
	and $0x10, %r8
	jz .Lld_partial_16

	movdqa MSG0, MSG1
	movdqu (SRC), MSG0

.Lld_partial_16:
	ret
ENDPROC(__load_partial)

/*
 * __store_partial: internal ABI
 * input:
 *   LEN - bytes
 *   DST - dst
 * output:
 *   T0   - first message block
 *   T1   - second message block
 * changed:
 *   %r8
 *   %r9
 *   %r10
 */
__store_partial:
	mov LEN, %r8
	mov DST, %r9

	cmp $16, %r8
	jl .Lst_partial_16

	movdqu T0, (%r9)
	movdqa T1, T0

	sub $16, %r8
	add $16, %r9

.Lst_partial_16:
	movq T0, %r10

	cmp $8, %r8
	jl .Lst_partial_8

	mov %r10, (%r9)
	psrldq $8, T0
	movq T0, %r10

	sub $8, %r8
	add $8, %r9

.Lst_partial_8:
	cmp $4, %r8
	jl .Lst_partial_4

	mov %r10d, (%r9)
	shr $32, %r10

	sub $4, %r8
	add $4, %r9

.Lst_partial_4:
	cmp $2, %r8
	jl .Lst_partial_2

	mov %r10w, (%r9)
	shr $0x10, %r10

	sub $2, %r8
	add $2, %r9

.Lst_partial_2:
	cmp $1, %r8
	jl .Lst_partial_1

	mov %r10b, (%r9)

.Lst_partial_1:
	ret
ENDPROC(__store_partial)

.macro update
	movdqa STATE7, T0
	aesenc STATE0, STATE7
	aesenc STATE1, STATE0
	aesenc STATE2, STATE1
	aesenc STATE3, STATE2
	aesenc STATE4, STATE3
	aesenc STATE5, STATE4
	aesenc STATE6, STATE5
	aesenc T0,     STATE6
.endm

.macro update0
	update
	pxor MSG0, STATE7
	pxor MSG1, STATE3
.endm

.macro update1
	update
	pxor MSG0, STATE6
	pxor MSG1, STATE2
.endm

.macro update2
	update
	pxor MSG0, STATE5
	pxor MSG1, STATE1
.endm

.macro update3
	update
	pxor MSG0, STATE4
	pxor MSG1, STATE0
.endm

.macro update4
	update
	pxor MSG0, STATE3
	pxor MSG1, STATE7
.endm

.macro update5
	update
	pxor MSG0, STATE2
	pxor MSG1, STATE6
.endm

.macro update6
	update
	pxor MSG0, STATE1
	pxor MSG1, STATE5
.endm

.macro update7
	update
	pxor MSG0, STATE0
	pxor MSG1, STATE4
.endm

.macro state_load
	movdqu 0x00(STATEP), STATE0
	movdqu 0x10(STATEP), STATE1
	movdqu 0x20(STATEP), STATE2
	movdqu 0x30(STATEP), STATE3
	movdqu 0x40(STATEP), STATE4
	movdqu 0x50(STATEP), STATE5
	movdqu 0x60(STATEP), STATE6
	movdqu 0x70(STATEP), STATE7
.endm

.macro state_store s0 s1 s2 s3 s4 s5 s6 s7
	movdqu \s7, 0x00(STATEP)
	movdqu \s0, 0x10(STATEP)
	movdqu \s1, 0x20(STATEP)
	movdqu \s2, 0x30(STATEP)
	movdqu \s3, 0x40(STATEP)
	movdqu \s4, 0x50(STATEP)
	movdqu \s5, 0x60(STATEP)
	movdqu \s6, 0x70(STATEP)
.endm

.macro state_store0
	state_store STATE0 STATE1 STATE2 STATE3 STATE4 STATE5 STATE6 STATE7
.endm

.macro state_store1
	state_store STATE7 STATE0 STATE1 STATE2 STATE3 STATE4 STATE5 STATE6
.endm

.macro state_store2
	state_store STATE6 STATE7 STATE0 STATE1 STATE2 STATE3 STATE4 STATE5
.endm

.macro state_store3
	state_store STATE5 STATE6 STATE7 STATE0 STATE1 STATE2 STATE3 STATE4
.endm

.macro state_store4
	state_store STATE4 STATE5 STATE6 STATE7 STATE0 STATE1 STATE2 STATE3
.endm

.macro state_store5
	state_store STATE3 STATE4 STATE5 STATE6 STATE7 STATE0 STATE1 STATE2
.endm

.macro state_store6
	state_store STATE2 STATE3 STATE4 STATE5 STATE6 STATE7 STATE0 STATE1
.endm

.macro state_store7
	state_store STATE1 STATE2 STATE3 STATE4 STATE5 STATE6 STATE7 STATE0
.endm

/*
 * void crypto_aegis128l_aesni_init(void *state, const void *key, const void *iv);
 */
ENTRY(crypto_aegis128l_aesni_init)
	FRAME_BEGIN

	/* load key: */
	movdqa (%rsi), MSG1
	movdqa MSG1, STATE0
	movdqa MSG1, STATE4
	movdqa MSG1, STATE5
	movdqa MSG1, STATE6
	movdqa MSG1, STATE7

	/* load IV: */
	movdqu (%rdx), MSG0
	pxor MSG0, STATE0
	pxor MSG0, STATE4

	/* load the constants: */
	movdqa .Laegis128l_const_0, STATE2
	movdqa .Laegis128l_const_1, STATE1
	movdqa STATE1, STATE3
	pxor STATE2, STATE5
	pxor STATE1, STATE6
	pxor STATE2, STATE7

	/* update 10 times with IV and KEY: */
	update0
	update1
	update2
	update3
	update4
	update5
	update6
	update7
	update0
	update1

	state_store1

	FRAME_END
	ret
ENDPROC(crypto_aegis128l_aesni_init)

.macro ad_block a i
	movdq\a (\i * 0x20 + 0x00)(SRC), MSG0
	movdq\a (\i * 0x20 + 0x10)(SRC), MSG1
	update\i
	sub $0x20, LEN
	cmp $0x20, LEN
	jl .Lad_out_\i
.endm

/*
 * void crypto_aegis128l_aesni_ad(void *state, unsigned int length,
 *                                const void *data);
 */
ENTRY(crypto_aegis128l_aesni_ad)
	FRAME_BEGIN

	cmp $0x20, LEN
	jb .Lad_out

	state_load

	mov  SRC, %r8
	and $0xf, %r8
	jnz .Lad_u_loop

.align 8
.Lad_a_loop:
	ad_block a 0
	ad_block a 1
	ad_block a 2
	ad_block a 3
	ad_block a 4
	ad_block a 5
	ad_block a 6
	ad_block a 7

	add $0x100, SRC
	jmp .Lad_a_loop

.align 8
.Lad_u_loop:
	ad_block u 0
	ad_block u 1
	ad_block u 2
	ad_block u 3
	ad_block u 4
	ad_block u 5
	ad_block u 6
	ad_block u 7

	add $0x100, SRC
	jmp .Lad_u_loop

.Lad_out_0:
	state_store0
	FRAME_END
	ret

.Lad_out_1:
	state_store1
	FRAME_END
	ret

.Lad_out_2:
	state_store2
	FRAME_END
	ret

.Lad_out_3:
	state_store3
	FRAME_END
	ret

.Lad_out_4:
	state_store4
	FRAME_END
	ret

.Lad_out_5:
	state_store5
	FRAME_END
	ret

.Lad_out_6:
	state_store6
	FRAME_END
	ret

.Lad_out_7:
	state_store7
	FRAME_END
	ret

.Lad_out:
	FRAME_END
	ret
ENDPROC(crypto_aegis128l_aesni_ad)

.macro crypt m0 m1 s0 s1 s2 s3 s4 s5 s6 s7
	pxor \s1, \m0
	pxor \s6, \m0
	movdqa \s2, T3
	pand \s3, T3
	pxor T3, \m0

	pxor \s2, \m1
	pxor \s5, \m1
	movdqa \s6, T3
	pand \s7, T3
	pxor T3, \m1
.endm

.macro crypt0 m0 m1
	crypt \m0 \m1 STATE0 STATE1 STATE2 STATE3 STATE4 STATE5 STATE6 STATE7
.endm

.macro crypt1 m0 m1
	crypt \m0 \m1 STATE7 STATE0 STATE1 STATE2 STATE3 STATE4 STATE5 STATE6
.endm

.macro crypt2 m0 m1
	crypt \m0 \m1 STATE6 STATE7 STATE0 STATE1 STATE2 STATE3 STATE4 STATE5
.endm

.macro crypt3 m0 m1
	crypt \m0 \m1 STATE5 STATE6 STATE7 STATE0 STATE1 STATE2 STATE3 STATE4
.endm

.macro crypt4 m0 m1
	crypt \m0 \m1 STATE4 STATE5 STATE6 STATE7 STATE0 STATE1 STATE2 STATE3
.endm

.macro crypt5 m0 m1
	crypt \m0 \m1 STATE3 STATE4 STATE5 STATE6 STATE7 STATE0 STATE1 STATE2
.endm

.macro crypt6 m0 m1
	crypt \m0 \m1 STATE2 STATE3 STATE4 STATE5 STATE6 STATE7 STATE0 STATE1
.endm

.macro crypt7 m0 m1
	crypt \m0 \m1 STATE1 STATE2 STATE3 STATE4 STATE5 STATE6 STATE7 STATE0
.endm

.macro encrypt_block a i
	movdq\a (\i * 0x20 + 0x00)(SRC), MSG0
	movdq\a (\i * 0x20 + 0x10)(SRC), MSG1
	movdqa MSG0, T0
	movdqa MSG1, T1
	crypt\i T0, T1
	movdq\a T0, (\i * 0x20 + 0x00)(DST)
	movdq\a T1, (\i * 0x20 + 0x10)(DST)

	update\i

	sub $0x20, LEN
	cmp $0x20, LEN
	jl .Lenc_out_\i
.endm

.macro decrypt_block a i
	movdq\a (\i * 0x20 + 0x00)(SRC), MSG0
	movdq\a (\i * 0x20 + 0x10)(SRC), MSG1
	crypt\i MSG0, MSG1
	movdq\a MSG0, (\i * 0x20 + 0x00)(DST)
	movdq\a MSG1, (\i * 0x20 + 0x10)(DST)

	update\i

	sub $0x20, LEN
	cmp $0x20, LEN
	jl .Ldec_out_\i
.endm

/*
 * void crypto_aegis128l_aesni_enc(void *state, unsigned int length,
 *                                 const void *src, void *dst);
 */
ENTRY(crypto_aegis128l_aesni_enc)
	FRAME_BEGIN

	cmp $0x20, LEN
	jb .Lenc_out

	state_load

	mov  SRC, %r8
	or   DST, %r8
	and $0xf, %r8
	jnz .Lenc_u_loop

.align 8
.Lenc_a_loop:
	encrypt_block a 0
	encrypt_block a 1
	encrypt_block a 2
	encrypt_block a 3
	encrypt_block a 4
	encrypt_block a 5
	encrypt_block a 6
	encrypt_block a 7

	add $0x100, SRC
	add $0x100, DST
	jmp .Lenc_a_loop

.align 8
.Lenc_u_loop:
	encrypt_block u 0
	encrypt_block u 1
	encrypt_block u 2
	encrypt_block u 3
	encrypt_block u 4
	encrypt_block u 5
	encrypt_block u 6
	encrypt_block u 7

	add $0x100, SRC
	add $0x100, DST
	jmp .Lenc_u_loop

.Lenc_out_0:
	state_store0
	FRAME_END
	ret

.Lenc_out_1:
	state_store1
	FRAME_END
	ret

.Lenc_out_2:
	state_store2
	FRAME_END
	ret

.Lenc_out_3:
	state_store3
	FRAME_END
	ret

.Lenc_out_4:
	state_store4
	FRAME_END
	ret

.Lenc_out_5:
	state_store5
	FRAME_END
	ret

.Lenc_out_6:
	state_store6
	FRAME_END
	ret

.Lenc_out_7:
	state_store7
	FRAME_END
	ret

.Lenc_out:
	FRAME_END
	ret
ENDPROC(crypto_aegis128l_aesni_enc)

/*
 * void crypto_aegis128l_aesni_enc_tail(void *state, unsigned int length,
 *                                      const void *src, void *dst);
 */
ENTRY(crypto_aegis128l_aesni_enc_tail)
	FRAME_BEGIN

	state_load

	/* encrypt message: */
	call __load_partial

	movdqa MSG0, T0
	movdqa MSG1, T1
	crypt0 T0, T1

	call __store_partial

	update0

	state_store0

	FRAME_END
	ret
ENDPROC(crypto_aegis128l_aesni_enc_tail)

/*
 * void crypto_aegis128l_aesni_dec(void *state, unsigned int length,
 *                                 const void *src, void *dst);
 */
ENTRY(crypto_aegis128l_aesni_dec)
	FRAME_BEGIN

	cmp $0x20, LEN
	jb .Ldec_out

	state_load

	mov  SRC, %r8
	or   DST, %r8
	and $0xF, %r8
	jnz .Ldec_u_loop

.align 8
.Ldec_a_loop:
	decrypt_block a 0
	decrypt_block a 1
	decrypt_block a 2
	decrypt_block a 3
	decrypt_block a 4
	decrypt_block a 5
	decrypt_block a 6
	decrypt_block a 7

	add $0x100, SRC
	add $0x100, DST
	jmp .Ldec_a_loop

.align 8
.Ldec_u_loop:
	decrypt_block u 0
	decrypt_block u 1
	decrypt_block u 2
	decrypt_block u 3
	decrypt_block u 4
	decrypt_block u 5
	decrypt_block u 6
	decrypt_block u 7

	add $0x100, SRC
	add $0x100, DST
	jmp .Ldec_u_loop

.Ldec_out_0:
	state_store0
	FRAME_END
	ret

.Ldec_out_1:
	state_store1
	FRAME_END
	ret

.Ldec_out_2:
	state_store2
	FRAME_END
	ret

.Ldec_out_3:
	state_store3
	FRAME_END
	ret

.Ldec_out_4:
	state_store4
	FRAME_END
	ret

.Ldec_out_5:
	state_store5
	FRAME_END
	ret

.Ldec_out_6:
	state_store6
	FRAME_END
	ret

.Ldec_out_7:
	state_store7
	FRAME_END
	ret

.Ldec_out:
	FRAME_END
	ret
ENDPROC(crypto_aegis128l_aesni_dec)

/*
 * void crypto_aegis128l_aesni_dec_tail(void *state, unsigned int length,
 *                                      const void *src, void *dst);
 */
ENTRY(crypto_aegis128l_aesni_dec_tail)
	FRAME_BEGIN

	state_load

	/* decrypt message: */
	call __load_partial

	crypt0 MSG0, MSG1

	movdqa MSG0, T0
	movdqa MSG1, T1
	call __store_partial

	/* mask with byte count: */
	movq LEN, T0
	punpcklbw T0, T0
	punpcklbw T0, T0
	punpcklbw T0, T0
	punpcklbw T0, T0
	movdqa T0, T1
	movdqa .Laegis128l_counter0, T2
	movdqa .Laegis128l_counter1, T3
	pcmpgtb T2, T0
	pcmpgtb T3, T1
	pand T0, MSG0
	pand T1, MSG1

	update0

	state_store0

	FRAME_END
	ret
ENDPROC(crypto_aegis128l_aesni_dec_tail)

/*
 * void crypto_aegis128l_aesni_final(void *state, void *tag_xor,
 *                                   u64 assoclen, u64 cryptlen);
 */
ENTRY(crypto_aegis128l_aesni_final)
	FRAME_BEGIN

	state_load

	/* prepare length block: */
	movq %rdx, MSG0
	movq %rcx, T0
	pslldq $8, T0
	pxor T0, MSG0
	psllq $3, MSG0 /* multiply by 8 (to get bit count) */

	pxor STATE2, MSG0
	movdqa MSG0, MSG1

	/* update state: */
	update0
	update1
	update2
	update3
	update4
	update5
	update6

	/* xor tag: */
	movdqu (%rsi), T0

	pxor STATE1, T0
	pxor STATE2, T0
	pxor STATE3, T0
	pxor STATE4, T0
	pxor STATE5, T0
	pxor STATE6, T0
	pxor STATE7, T0

	movdqu T0, (%rsi)

	FRAME_END
	ret
ENDPROC(crypto_aegis128l_aesni_final)