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-rw-r--r--arch/arm64/crypto/aes-cipher-core.S132
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diff --git a/arch/arm64/crypto/aes-cipher-core.S b/arch/arm64/crypto/aes-cipher-core.S
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+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Scalar AES core transform
+ *
+ * Copyright (C) 2017 Linaro Ltd <ard.biesheuvel@linaro.org>
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/cache.h>
+
+ .text
+
+ rk .req x0
+ out .req x1
+ in .req x2
+ rounds .req x3
+ tt .req x2
+
+ .macro __pair1, sz, op, reg0, reg1, in0, in1e, in1d, shift
+ .ifc \op\shift, b0
+ ubfiz \reg0, \in0, #2, #8
+ ubfiz \reg1, \in1e, #2, #8
+ .else
+ ubfx \reg0, \in0, #\shift, #8
+ ubfx \reg1, \in1e, #\shift, #8
+ .endif
+
+ /*
+ * AArch64 cannot do byte size indexed loads from a table containing
+ * 32-bit quantities, i.e., 'ldrb w12, [tt, w12, uxtw #2]' is not a
+ * valid instruction. So perform the shift explicitly first for the
+ * high bytes (the low byte is shifted implicitly by using ubfiz rather
+ * than ubfx above)
+ */
+ .ifnc \op, b
+ ldr \reg0, [tt, \reg0, uxtw #2]
+ ldr \reg1, [tt, \reg1, uxtw #2]
+ .else
+ .if \shift > 0
+ lsl \reg0, \reg0, #2
+ lsl \reg1, \reg1, #2
+ .endif
+ ldrb \reg0, [tt, \reg0, uxtw]
+ ldrb \reg1, [tt, \reg1, uxtw]
+ .endif
+ .endm
+
+ .macro __pair0, sz, op, reg0, reg1, in0, in1e, in1d, shift
+ ubfx \reg0, \in0, #\shift, #8
+ ubfx \reg1, \in1d, #\shift, #8
+ ldr\op \reg0, [tt, \reg0, uxtw #\sz]
+ ldr\op \reg1, [tt, \reg1, uxtw #\sz]
+ .endm
+
+ .macro __hround, out0, out1, in0, in1, in2, in3, t0, t1, enc, sz, op
+ ldp \out0, \out1, [rk], #8
+
+ __pair\enc \sz, \op, w12, w13, \in0, \in1, \in3, 0
+ __pair\enc \sz, \op, w14, w15, \in1, \in2, \in0, 8
+ __pair\enc \sz, \op, w16, w17, \in2, \in3, \in1, 16
+ __pair\enc \sz, \op, \t0, \t1, \in3, \in0, \in2, 24
+
+ eor \out0, \out0, w12
+ eor \out1, \out1, w13
+ eor \out0, \out0, w14, ror #24
+ eor \out1, \out1, w15, ror #24
+ eor \out0, \out0, w16, ror #16
+ eor \out1, \out1, w17, ror #16
+ eor \out0, \out0, \t0, ror #8
+ eor \out1, \out1, \t1, ror #8
+ .endm
+
+ .macro fround, out0, out1, out2, out3, in0, in1, in2, in3, sz=2, op
+ __hround \out0, \out1, \in0, \in1, \in2, \in3, \out2, \out3, 1, \sz, \op
+ __hround \out2, \out3, \in2, \in3, \in0, \in1, \in1, \in2, 1, \sz, \op
+ .endm
+
+ .macro iround, out0, out1, out2, out3, in0, in1, in2, in3, sz=2, op
+ __hround \out0, \out1, \in0, \in3, \in2, \in1, \out2, \out3, 0, \sz, \op
+ __hround \out2, \out3, \in2, \in1, \in0, \in3, \in1, \in0, 0, \sz, \op
+ .endm
+
+ .macro do_crypt, round, ttab, ltab, bsz
+ ldp w4, w5, [in]
+ ldp w6, w7, [in, #8]
+ ldp w8, w9, [rk], #16
+ ldp w10, w11, [rk, #-8]
+
+CPU_BE( rev w4, w4 )
+CPU_BE( rev w5, w5 )
+CPU_BE( rev w6, w6 )
+CPU_BE( rev w7, w7 )
+
+ eor w4, w4, w8
+ eor w5, w5, w9
+ eor w6, w6, w10
+ eor w7, w7, w11
+
+ adr_l tt, \ttab
+
+ tbnz rounds, #1, 1f
+
+0: \round w8, w9, w10, w11, w4, w5, w6, w7
+ \round w4, w5, w6, w7, w8, w9, w10, w11
+
+1: subs rounds, rounds, #4
+ \round w8, w9, w10, w11, w4, w5, w6, w7
+ b.ls 3f
+2: \round w4, w5, w6, w7, w8, w9, w10, w11
+ b 0b
+3: adr_l tt, \ltab
+ \round w4, w5, w6, w7, w8, w9, w10, w11, \bsz, b
+
+CPU_BE( rev w4, w4 )
+CPU_BE( rev w5, w5 )
+CPU_BE( rev w6, w6 )
+CPU_BE( rev w7, w7 )
+
+ stp w4, w5, [out]
+ stp w6, w7, [out, #8]
+ ret
+ .endm
+
+SYM_FUNC_START(__aes_arm64_encrypt)
+ do_crypt fround, crypto_ft_tab, crypto_ft_tab + 1, 2
+SYM_FUNC_END(__aes_arm64_encrypt)
+
+ .align 5
+SYM_FUNC_START(__aes_arm64_decrypt)
+ do_crypt iround, crypto_it_tab, crypto_aes_inv_sbox, 0
+SYM_FUNC_END(__aes_arm64_decrypt)