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| /* SPDX-License-Identifier: GPL-2.0-only */
| /*
| * aes-ce-core.S - AES in CBC/CTR/XTS mode using ARMv8 Crypto Extensions
| *
| * Copyright (C) 2015 Linaro Ltd <ard.biesheuvel@linaro.org>
| */
|
| #include <linux/linkage.h>
| #include <asm/assembler.h>
|
| .text
| .arch armv8-a
| .fpu crypto-neon-fp-armv8
| .align 3
|
| .macro enc_round, state, key
| aese.8 \state, \key
| aesmc.8 \state, \state
| .endm
|
| .macro dec_round, state, key
| aesd.8 \state, \key
| aesimc.8 \state, \state
| .endm
|
| .macro enc_dround, key1, key2
| enc_round q0, \key1
| enc_round q0, \key2
| .endm
|
| .macro dec_dround, key1, key2
| dec_round q0, \key1
| dec_round q0, \key2
| .endm
|
| .macro enc_fround, key1, key2, key3
| enc_round q0, \key1
| aese.8 q0, \key2
| veor q0, q0, \key3
| .endm
|
| .macro dec_fround, key1, key2, key3
| dec_round q0, \key1
| aesd.8 q0, \key2
| veor q0, q0, \key3
| .endm
|
| .macro enc_dround_4x, key1, key2
| enc_round q0, \key1
| enc_round q1, \key1
| enc_round q2, \key1
| enc_round q3, \key1
| enc_round q0, \key2
| enc_round q1, \key2
| enc_round q2, \key2
| enc_round q3, \key2
| .endm
|
| .macro dec_dround_4x, key1, key2
| dec_round q0, \key1
| dec_round q1, \key1
| dec_round q2, \key1
| dec_round q3, \key1
| dec_round q0, \key2
| dec_round q1, \key2
| dec_round q2, \key2
| dec_round q3, \key2
| .endm
|
| .macro enc_fround_4x, key1, key2, key3
| enc_round q0, \key1
| enc_round q1, \key1
| enc_round q2, \key1
| enc_round q3, \key1
| aese.8 q0, \key2
| aese.8 q1, \key2
| aese.8 q2, \key2
| aese.8 q3, \key2
| veor q0, q0, \key3
| veor q1, q1, \key3
| veor q2, q2, \key3
| veor q3, q3, \key3
| .endm
|
| .macro dec_fround_4x, key1, key2, key3
| dec_round q0, \key1
| dec_round q1, \key1
| dec_round q2, \key1
| dec_round q3, \key1
| aesd.8 q0, \key2
| aesd.8 q1, \key2
| aesd.8 q2, \key2
| aesd.8 q3, \key2
| veor q0, q0, \key3
| veor q1, q1, \key3
| veor q2, q2, \key3
| veor q3, q3, \key3
| .endm
|
| .macro do_block, dround, fround
| cmp r3, #12 @ which key size?
| vld1.32 {q10-q11}, [ip]!
| \dround q8, q9
| vld1.32 {q12-q13}, [ip]!
| \dround q10, q11
| vld1.32 {q10-q11}, [ip]!
| \dround q12, q13
| vld1.32 {q12-q13}, [ip]!
| \dround q10, q11
| blo 0f @ AES-128: 10 rounds
| vld1.32 {q10-q11}, [ip]!
| \dround q12, q13
| beq 1f @ AES-192: 12 rounds
| vld1.32 {q12-q13}, [ip]
| \dround q10, q11
| 0: \fround q12, q13, q14
| bx lr
|
| 1: \fround q10, q11, q14
| bx lr
| .endm
|
| /*
| * Internal, non-AAPCS compliant functions that implement the core AES
| * transforms. These should preserve all registers except q0 - q2 and ip
| * Arguments:
| * q0 : first in/output block
| * q1 : second in/output block (_4x version only)
| * q2 : third in/output block (_4x version only)
| * q3 : fourth in/output block (_4x version only)
| * q8 : first round key
| * q9 : secound round key
| * q14 : final round key
| * r2 : address of round key array
| * r3 : number of rounds
| */
| .align 6
| aes_encrypt:
| add ip, r2, #32 @ 3rd round key
| .Laes_encrypt_tweak:
| do_block enc_dround, enc_fround
| ENDPROC(aes_encrypt)
|
| .align 6
| aes_decrypt:
| add ip, r2, #32 @ 3rd round key
| do_block dec_dround, dec_fround
| ENDPROC(aes_decrypt)
|
| .align 6
| aes_encrypt_4x:
| add ip, r2, #32 @ 3rd round key
| do_block enc_dround_4x, enc_fround_4x
| ENDPROC(aes_encrypt_4x)
|
| .align 6
| aes_decrypt_4x:
| add ip, r2, #32 @ 3rd round key
| do_block dec_dround_4x, dec_fround_4x
| ENDPROC(aes_decrypt_4x)
|
| .macro prepare_key, rk, rounds
| add ip, \rk, \rounds, lsl #4
| vld1.32 {q8-q9}, [\rk] @ load first 2 round keys
| vld1.32 {q14}, [ip] @ load last round key
| .endm
|
| /*
| * aes_ecb_encrypt(u8 out[], u8 const in[], u32 const rk[], int rounds,
| * int blocks)
| * aes_ecb_decrypt(u8 out[], u8 const in[], u32 const rk[], int rounds,
| * int blocks)
| */
| ENTRY(ce_aes_ecb_encrypt)
| push {r4, lr}
| ldr r4, [sp, #8]
| prepare_key r2, r3
| .Lecbencloop4x:
| subs r4, r4, #4
| bmi .Lecbenc1x
| vld1.8 {q0-q1}, [r1]!
| vld1.8 {q2-q3}, [r1]!
| bl aes_encrypt_4x
| vst1.8 {q0-q1}, [r0]!
| vst1.8 {q2-q3}, [r0]!
| b .Lecbencloop4x
| .Lecbenc1x:
| adds r4, r4, #4
| beq .Lecbencout
| .Lecbencloop:
| vld1.8 {q0}, [r1]!
| bl aes_encrypt
| vst1.8 {q0}, [r0]!
| subs r4, r4, #1
| bne .Lecbencloop
| .Lecbencout:
| pop {r4, pc}
| ENDPROC(ce_aes_ecb_encrypt)
|
| ENTRY(ce_aes_ecb_decrypt)
| push {r4, lr}
| ldr r4, [sp, #8]
| prepare_key r2, r3
| .Lecbdecloop4x:
| subs r4, r4, #4
| bmi .Lecbdec1x
| vld1.8 {q0-q1}, [r1]!
| vld1.8 {q2-q3}, [r1]!
| bl aes_decrypt_4x
| vst1.8 {q0-q1}, [r0]!
| vst1.8 {q2-q3}, [r0]!
| b .Lecbdecloop4x
| .Lecbdec1x:
| adds r4, r4, #4
| beq .Lecbdecout
| .Lecbdecloop:
| vld1.8 {q0}, [r1]!
| bl aes_decrypt
| vst1.8 {q0}, [r0]!
| subs r4, r4, #1
| bne .Lecbdecloop
| .Lecbdecout:
| pop {r4, pc}
| ENDPROC(ce_aes_ecb_decrypt)
|
| /*
| * aes_cbc_encrypt(u8 out[], u8 const in[], u32 const rk[], int rounds,
| * int blocks, u8 iv[])
| * aes_cbc_decrypt(u8 out[], u8 const in[], u32 const rk[], int rounds,
| * int blocks, u8 iv[])
| */
| ENTRY(ce_aes_cbc_encrypt)
| push {r4-r6, lr}
| ldrd r4, r5, [sp, #16]
| vld1.8 {q0}, [r5]
| prepare_key r2, r3
| .Lcbcencloop:
| vld1.8 {q1}, [r1]! @ get next pt block
| veor q0, q0, q1 @ ..and xor with iv
| bl aes_encrypt
| vst1.8 {q0}, [r0]!
| subs r4, r4, #1
| bne .Lcbcencloop
| vst1.8 {q0}, [r5]
| pop {r4-r6, pc}
| ENDPROC(ce_aes_cbc_encrypt)
|
| ENTRY(ce_aes_cbc_decrypt)
| push {r4-r6, lr}
| ldrd r4, r5, [sp, #16]
| vld1.8 {q15}, [r5] @ keep iv in q15
| prepare_key r2, r3
| .Lcbcdecloop4x:
| subs r4, r4, #4
| bmi .Lcbcdec1x
| vld1.8 {q0-q1}, [r1]!
| vld1.8 {q2-q3}, [r1]!
| vmov q4, q0
| vmov q5, q1
| vmov q6, q2
| vmov q7, q3
| bl aes_decrypt_4x
| veor q0, q0, q15
| veor q1, q1, q4
| veor q2, q2, q5
| veor q3, q3, q6
| vmov q15, q7
| vst1.8 {q0-q1}, [r0]!
| vst1.8 {q2-q3}, [r0]!
| b .Lcbcdecloop4x
| .Lcbcdec1x:
| adds r4, r4, #4
| beq .Lcbcdecout
| vmov q6, q14 @ preserve last round key
| .Lcbcdecloop:
| vld1.8 {q0}, [r1]! @ get next ct block
| veor q14, q15, q6 @ combine prev ct with last key
| vmov q15, q0
| bl aes_decrypt
| vst1.8 {q0}, [r0]!
| subs r4, r4, #1
| bne .Lcbcdecloop
| .Lcbcdecout:
| vst1.8 {q15}, [r5] @ keep iv in q15
| pop {r4-r6, pc}
| ENDPROC(ce_aes_cbc_decrypt)
|
|
| /*
| * ce_aes_cbc_cts_encrypt(u8 out[], u8 const in[], u32 const rk[],
| * int rounds, int bytes, u8 const iv[])
| * ce_aes_cbc_cts_decrypt(u8 out[], u8 const in[], u32 const rk[],
| * int rounds, int bytes, u8 const iv[])
| */
|
| ENTRY(ce_aes_cbc_cts_encrypt)
| push {r4-r6, lr}
| ldrd r4, r5, [sp, #16]
|
| movw ip, :lower16:.Lcts_permute_table
| movt ip, :upper16:.Lcts_permute_table
| sub r4, r4, #16
| add lr, ip, #32
| add ip, ip, r4
| sub lr, lr, r4
| vld1.8 {q5}, [ip]
| vld1.8 {q6}, [lr]
|
| add ip, r1, r4
| vld1.8 {q0}, [r1] @ overlapping loads
| vld1.8 {q3}, [ip]
|
| vld1.8 {q1}, [r5] @ get iv
| prepare_key r2, r3
|
| veor q0, q0, q1 @ xor with iv
| bl aes_encrypt
|
| vtbl.8 d4, {d0-d1}, d10
| vtbl.8 d5, {d0-d1}, d11
| vtbl.8 d2, {d6-d7}, d12
| vtbl.8 d3, {d6-d7}, d13
|
| veor q0, q0, q1
| bl aes_encrypt
|
| add r4, r0, r4
| vst1.8 {q2}, [r4] @ overlapping stores
| vst1.8 {q0}, [r0]
|
| pop {r4-r6, pc}
| ENDPROC(ce_aes_cbc_cts_encrypt)
|
| ENTRY(ce_aes_cbc_cts_decrypt)
| push {r4-r6, lr}
| ldrd r4, r5, [sp, #16]
|
| movw ip, :lower16:.Lcts_permute_table
| movt ip, :upper16:.Lcts_permute_table
| sub r4, r4, #16
| add lr, ip, #32
| add ip, ip, r4
| sub lr, lr, r4
| vld1.8 {q5}, [ip]
| vld1.8 {q6}, [lr]
|
| add ip, r1, r4
| vld1.8 {q0}, [r1] @ overlapping loads
| vld1.8 {q1}, [ip]
|
| vld1.8 {q3}, [r5] @ get iv
| prepare_key r2, r3
|
| bl aes_decrypt
|
| vtbl.8 d4, {d0-d1}, d10
| vtbl.8 d5, {d0-d1}, d11
| vtbx.8 d0, {d2-d3}, d12
| vtbx.8 d1, {d2-d3}, d13
|
| veor q1, q1, q2
| bl aes_decrypt
| veor q0, q0, q3 @ xor with iv
|
| add r4, r0, r4
| vst1.8 {q1}, [r4] @ overlapping stores
| vst1.8 {q0}, [r0]
|
| pop {r4-r6, pc}
| ENDPROC(ce_aes_cbc_cts_decrypt)
|
|
| /*
| * aes_ctr_encrypt(u8 out[], u8 const in[], u32 const rk[], int rounds,
| * int blocks, u8 ctr[])
| */
| ENTRY(ce_aes_ctr_encrypt)
| push {r4-r6, lr}
| ldrd r4, r5, [sp, #16]
| vld1.8 {q7}, [r5] @ load ctr
| prepare_key r2, r3
| vmov r6, s31 @ keep swabbed ctr in r6
| rev r6, r6
| cmn r6, r4 @ 32 bit overflow?
| bcs .Lctrloop
| .Lctrloop4x:
| subs r4, r4, #4
| bmi .Lctr1x
|
| /*
| * NOTE: the sequence below has been carefully tweaked to avoid
| * a silicon erratum that exists in Cortex-A57 (#1742098) and
| * Cortex-A72 (#1655431) cores, where AESE/AESMC instruction pairs
| * may produce an incorrect result if they take their input from a
| * register of which a single 32-bit lane has been updated the last
| * time it was modified. To work around this, the lanes of registers
| * q0-q3 below are not manipulated individually, and the different
| * counter values are prepared by successive manipulations of q7.
| */
| add ip, r6, #1
| vmov q0, q7
| rev ip, ip
| add lr, r6, #2
| vmov s31, ip @ set lane 3 of q1 via q7
| add ip, r6, #3
| rev lr, lr
| vmov q1, q7
| vmov s31, lr @ set lane 3 of q2 via q7
| rev ip, ip
| vmov q2, q7
| vmov s31, ip @ set lane 3 of q3 via q7
| add r6, r6, #4
| vmov q3, q7
|
| vld1.8 {q4-q5}, [r1]!
| vld1.8 {q6}, [r1]!
| vld1.8 {q15}, [r1]!
| bl aes_encrypt_4x
| veor q0, q0, q4
| veor q1, q1, q5
| veor q2, q2, q6
| veor q3, q3, q15
| rev ip, r6
| vst1.8 {q0-q1}, [r0]!
| vst1.8 {q2-q3}, [r0]!
| vmov s31, ip
| b .Lctrloop4x
| .Lctr1x:
| adds r4, r4, #4
| beq .Lctrout
| .Lctrloop:
| vmov q0, q7
| bl aes_encrypt
|
| adds r6, r6, #1 @ increment BE ctr
| rev ip, r6
| vmov s31, ip
| bcs .Lctrcarry
|
| .Lctrcarrydone:
| subs r4, r4, #1
| bmi .Lctrtailblock @ blocks < 0 means tail block
| vld1.8 {q3}, [r1]!
| veor q3, q0, q3
| vst1.8 {q3}, [r0]!
| bne .Lctrloop
|
| .Lctrout:
| vst1.8 {q7}, [r5] @ return next CTR value
| pop {r4-r6, pc}
|
| .Lctrtailblock:
| vst1.8 {q0}, [r0, :64] @ return the key stream
| b .Lctrout
|
| .Lctrcarry:
| .irp sreg, s30, s29, s28
| vmov ip, \sreg @ load next word of ctr
| rev ip, ip @ ... to handle the carry
| adds ip, ip, #1
| rev ip, ip
| vmov \sreg, ip
| bcc .Lctrcarrydone
| .endr
| b .Lctrcarrydone
| ENDPROC(ce_aes_ctr_encrypt)
|
| /*
| * aes_xts_encrypt(u8 out[], u8 const in[], u32 const rk1[], int rounds,
| * int bytes, u8 iv[], u32 const rk2[], int first)
| * aes_xts_decrypt(u8 out[], u8 const in[], u32 const rk1[], int rounds,
| * int bytes, u8 iv[], u32 const rk2[], int first)
| */
|
| .macro next_tweak, out, in, const, tmp
| vshr.s64 \tmp, \in, #63
| vand \tmp, \tmp, \const
| vadd.u64 \out, \in, \in
| vext.8 \tmp, \tmp, \tmp, #8
| veor \out, \out, \tmp
| .endm
|
| ce_aes_xts_init:
| vmov.i32 d30, #0x87 @ compose tweak mask vector
| vmovl.u32 q15, d30
| vshr.u64 d30, d31, #7
|
| ldrd r4, r5, [sp, #16] @ load args
| ldr r6, [sp, #28]
| vld1.8 {q0}, [r5] @ load iv
| teq r6, #1 @ start of a block?
| bxne lr
|
| @ Encrypt the IV in q0 with the second AES key. This should only
| @ be done at the start of a block.
| ldr r6, [sp, #24] @ load AES key 2
| prepare_key r6, r3
| add ip, r6, #32 @ 3rd round key of key 2
| b .Laes_encrypt_tweak @ tail call
| ENDPROC(ce_aes_xts_init)
|
| ENTRY(ce_aes_xts_encrypt)
| push {r4-r6, lr}
|
| bl ce_aes_xts_init @ run shared prologue
| prepare_key r2, r3
| vmov q4, q0
|
| teq r6, #0 @ start of a block?
| bne .Lxtsenc4x
|
| .Lxtsencloop4x:
| next_tweak q4, q4, q15, q10
| .Lxtsenc4x:
| subs r4, r4, #64
| bmi .Lxtsenc1x
| vld1.8 {q0-q1}, [r1]! @ get 4 pt blocks
| vld1.8 {q2-q3}, [r1]!
| next_tweak q5, q4, q15, q10
| veor q0, q0, q4
| next_tweak q6, q5, q15, q10
| veor q1, q1, q5
| next_tweak q7, q6, q15, q10
| veor q2, q2, q6
| veor q3, q3, q7
| bl aes_encrypt_4x
| veor q0, q0, q4
| veor q1, q1, q5
| veor q2, q2, q6
| veor q3, q3, q7
| vst1.8 {q0-q1}, [r0]! @ write 4 ct blocks
| vst1.8 {q2-q3}, [r0]!
| vmov q4, q7
| teq r4, #0
| beq .Lxtsencret
| b .Lxtsencloop4x
| .Lxtsenc1x:
| adds r4, r4, #64
| beq .Lxtsencout
| subs r4, r4, #16
| bmi .LxtsencctsNx
| .Lxtsencloop:
| vld1.8 {q0}, [r1]!
| .Lxtsencctsout:
| veor q0, q0, q4
| bl aes_encrypt
| veor q0, q0, q4
| teq r4, #0
| beq .Lxtsencout
| subs r4, r4, #16
| next_tweak q4, q4, q15, q6
| bmi .Lxtsenccts
| vst1.8 {q0}, [r0]!
| b .Lxtsencloop
| .Lxtsencout:
| vst1.8 {q0}, [r0]
| .Lxtsencret:
| vst1.8 {q4}, [r5]
| pop {r4-r6, pc}
|
| .LxtsencctsNx:
| vmov q0, q3
| sub r0, r0, #16
| .Lxtsenccts:
| movw ip, :lower16:.Lcts_permute_table
| movt ip, :upper16:.Lcts_permute_table
|
| add r1, r1, r4 @ rewind input pointer
| add r4, r4, #16 @ # bytes in final block
| add lr, ip, #32
| add ip, ip, r4
| sub lr, lr, r4
| add r4, r0, r4 @ output address of final block
|
| vld1.8 {q1}, [r1] @ load final partial block
| vld1.8 {q2}, [ip]
| vld1.8 {q3}, [lr]
|
| vtbl.8 d4, {d0-d1}, d4
| vtbl.8 d5, {d0-d1}, d5
| vtbx.8 d0, {d2-d3}, d6
| vtbx.8 d1, {d2-d3}, d7
|
| vst1.8 {q2}, [r4] @ overlapping stores
| mov r4, #0
| b .Lxtsencctsout
| ENDPROC(ce_aes_xts_encrypt)
|
|
| ENTRY(ce_aes_xts_decrypt)
| push {r4-r6, lr}
|
| bl ce_aes_xts_init @ run shared prologue
| prepare_key r2, r3
| vmov q4, q0
|
| /* subtract 16 bytes if we are doing CTS */
| tst r4, #0xf
| subne r4, r4, #0x10
|
| teq r6, #0 @ start of a block?
| bne .Lxtsdec4x
|
| .Lxtsdecloop4x:
| next_tweak q4, q4, q15, q10
| .Lxtsdec4x:
| subs r4, r4, #64
| bmi .Lxtsdec1x
| vld1.8 {q0-q1}, [r1]! @ get 4 ct blocks
| vld1.8 {q2-q3}, [r1]!
| next_tweak q5, q4, q15, q10
| veor q0, q0, q4
| next_tweak q6, q5, q15, q10
| veor q1, q1, q5
| next_tweak q7, q6, q15, q10
| veor q2, q2, q6
| veor q3, q3, q7
| bl aes_decrypt_4x
| veor q0, q0, q4
| veor q1, q1, q5
| veor q2, q2, q6
| veor q3, q3, q7
| vst1.8 {q0-q1}, [r0]! @ write 4 pt blocks
| vst1.8 {q2-q3}, [r0]!
| vmov q4, q7
| teq r4, #0
| beq .Lxtsdecout
| b .Lxtsdecloop4x
| .Lxtsdec1x:
| adds r4, r4, #64
| beq .Lxtsdecout
| subs r4, r4, #16
| .Lxtsdecloop:
| vld1.8 {q0}, [r1]!
| bmi .Lxtsdeccts
| .Lxtsdecctsout:
| veor q0, q0, q4
| bl aes_decrypt
| veor q0, q0, q4
| vst1.8 {q0}, [r0]!
| teq r4, #0
| beq .Lxtsdecout
| subs r4, r4, #16
| next_tweak q4, q4, q15, q6
| b .Lxtsdecloop
| .Lxtsdecout:
| vst1.8 {q4}, [r5]
| pop {r4-r6, pc}
|
| .Lxtsdeccts:
| movw ip, :lower16:.Lcts_permute_table
| movt ip, :upper16:.Lcts_permute_table
|
| add r1, r1, r4 @ rewind input pointer
| add r4, r4, #16 @ # bytes in final block
| add lr, ip, #32
| add ip, ip, r4
| sub lr, lr, r4
| add r4, r0, r4 @ output address of final block
|
| next_tweak q5, q4, q15, q6
|
| vld1.8 {q1}, [r1] @ load final partial block
| vld1.8 {q2}, [ip]
| vld1.8 {q3}, [lr]
|
| veor q0, q0, q5
| bl aes_decrypt
| veor q0, q0, q5
|
| vtbl.8 d4, {d0-d1}, d4
| vtbl.8 d5, {d0-d1}, d5
| vtbx.8 d0, {d2-d3}, d6
| vtbx.8 d1, {d2-d3}, d7
|
| vst1.8 {q2}, [r4] @ overlapping stores
| mov r4, #0
| b .Lxtsdecctsout
| ENDPROC(ce_aes_xts_decrypt)
|
| /*
| * u32 ce_aes_sub(u32 input) - use the aese instruction to perform the
| * AES sbox substitution on each byte in
| * 'input'
| */
| ENTRY(ce_aes_sub)
| vdup.32 q1, r0
| veor q0, q0, q0
| aese.8 q0, q1
| vmov r0, s0
| bx lr
| ENDPROC(ce_aes_sub)
|
| /*
| * void ce_aes_invert(u8 *dst, u8 *src) - perform the Inverse MixColumns
| * operation on round key *src
| */
| ENTRY(ce_aes_invert)
| vld1.32 {q0}, [r1]
| aesimc.8 q0, q0
| vst1.32 {q0}, [r0]
| bx lr
| ENDPROC(ce_aes_invert)
|
| .section ".rodata", "a"
| .align 6
| .Lcts_permute_table:
| .byte 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
| .byte 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
| .byte 0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7
| .byte 0x8, 0x9, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf
| .byte 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
| .byte 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
|
|
