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Diffstat (limited to 'vendor/golang.org/x/crypto/internal/chacha20/asm_s390x.s')
| -rw-r--r-- | vendor/golang.org/x/crypto/internal/chacha20/asm_s390x.s | 283 |
1 files changed, 283 insertions, 0 deletions
diff --git a/vendor/golang.org/x/crypto/internal/chacha20/asm_s390x.s b/vendor/golang.org/x/crypto/internal/chacha20/asm_s390x.s new file mode 100644 index 0000000..98427c5 --- /dev/null +++ b/vendor/golang.org/x/crypto/internal/chacha20/asm_s390x.s @@ -0,0 +1,283 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build s390x,!gccgo,!appengine + +#include "go_asm.h" +#include "textflag.h" + +// This is an implementation of the ChaCha20 encryption algorithm as +// specified in RFC 7539. It uses vector instructions to compute +// 4 keystream blocks in parallel (256 bytes) which are then XORed +// with the bytes in the input slice. + +GLOBL ·constants<>(SB), RODATA|NOPTR, $32 +// BSWAP: swap bytes in each 4-byte element +DATA ·constants<>+0x00(SB)/4, $0x03020100 +DATA ·constants<>+0x04(SB)/4, $0x07060504 +DATA ·constants<>+0x08(SB)/4, $0x0b0a0908 +DATA ·constants<>+0x0c(SB)/4, $0x0f0e0d0c +// J0: [j0, j1, j2, j3] +DATA ·constants<>+0x10(SB)/4, $0x61707865 +DATA ·constants<>+0x14(SB)/4, $0x3320646e +DATA ·constants<>+0x18(SB)/4, $0x79622d32 +DATA ·constants<>+0x1c(SB)/4, $0x6b206574 + +// EXRL targets: +TEXT ·mvcSrcToBuf(SB), NOFRAME|NOSPLIT, $0 + MVC $1, (R1), (R8) + RET + +TEXT ·mvcBufToDst(SB), NOFRAME|NOSPLIT, $0 + MVC $1, (R8), (R9) + RET + +#define BSWAP V5 +#define J0 V6 +#define KEY0 V7 +#define KEY1 V8 +#define NONCE V9 +#define CTR V10 +#define M0 V11 +#define M1 V12 +#define M2 V13 +#define M3 V14 +#define INC V15 +#define X0 V16 +#define X1 V17 +#define X2 V18 +#define X3 V19 +#define X4 V20 +#define X5 V21 +#define X6 V22 +#define X7 V23 +#define X8 V24 +#define X9 V25 +#define X10 V26 +#define X11 V27 +#define X12 V28 +#define X13 V29 +#define X14 V30 +#define X15 V31 + +#define NUM_ROUNDS 20 + +#define ROUND4(a0, a1, a2, a3, b0, b1, b2, b3, c0, c1, c2, c3, d0, d1, d2, d3) \ + VAF a1, a0, a0 \ + VAF b1, b0, b0 \ + VAF c1, c0, c0 \ + VAF d1, d0, d0 \ + VX a0, a2, a2 \ + VX b0, b2, b2 \ + VX c0, c2, c2 \ + VX d0, d2, d2 \ + VERLLF $16, a2, a2 \ + VERLLF $16, b2, b2 \ + VERLLF $16, c2, c2 \ + VERLLF $16, d2, d2 \ + VAF a2, a3, a3 \ + VAF b2, b3, b3 \ + VAF c2, c3, c3 \ + VAF d2, d3, d3 \ + VX a3, a1, a1 \ + VX b3, b1, b1 \ + VX c3, c1, c1 \ + VX d3, d1, d1 \ + VERLLF $12, a1, a1 \ + VERLLF $12, b1, b1 \ + VERLLF $12, c1, c1 \ + VERLLF $12, d1, d1 \ + VAF a1, a0, a0 \ + VAF b1, b0, b0 \ + VAF c1, c0, c0 \ + VAF d1, d0, d0 \ + VX a0, a2, a2 \ + VX b0, b2, b2 \ + VX c0, c2, c2 \ + VX d0, d2, d2 \ + VERLLF $8, a2, a2 \ + VERLLF $8, b2, b2 \ + VERLLF $8, c2, c2 \ + VERLLF $8, d2, d2 \ + VAF a2, a3, a3 \ + VAF b2, b3, b3 \ + VAF c2, c3, c3 \ + VAF d2, d3, d3 \ + VX a3, a1, a1 \ + VX b3, b1, b1 \ + VX c3, c1, c1 \ + VX d3, d1, d1 \ + VERLLF $7, a1, a1 \ + VERLLF $7, b1, b1 \ + VERLLF $7, c1, c1 \ + VERLLF $7, d1, d1 + +#define PERMUTE(mask, v0, v1, v2, v3) \ + VPERM v0, v0, mask, v0 \ + VPERM v1, v1, mask, v1 \ + VPERM v2, v2, mask, v2 \ + VPERM v3, v3, mask, v3 + +#define ADDV(x, v0, v1, v2, v3) \ + VAF x, v0, v0 \ + VAF x, v1, v1 \ + VAF x, v2, v2 \ + VAF x, v3, v3 + +#define XORV(off, dst, src, v0, v1, v2, v3) \ + VLM off(src), M0, M3 \ + PERMUTE(BSWAP, v0, v1, v2, v3) \ + VX v0, M0, M0 \ + VX v1, M1, M1 \ + VX v2, M2, M2 \ + VX v3, M3, M3 \ + VSTM M0, M3, off(dst) + +#define SHUFFLE(a, b, c, d, t, u, v, w) \ + VMRHF a, c, t \ // t = {a[0], c[0], a[1], c[1]} + VMRHF b, d, u \ // u = {b[0], d[0], b[1], d[1]} + VMRLF a, c, v \ // v = {a[2], c[2], a[3], c[3]} + VMRLF b, d, w \ // w = {b[2], d[2], b[3], d[3]} + VMRHF t, u, a \ // a = {a[0], b[0], c[0], d[0]} + VMRLF t, u, b \ // b = {a[1], b[1], c[1], d[1]} + VMRHF v, w, c \ // c = {a[2], b[2], c[2], d[2]} + VMRLF v, w, d // d = {a[3], b[3], c[3], d[3]} + +// func xorKeyStreamVX(dst, src []byte, key *[8]uint32, nonce *[3]uint32, counter *uint32, buf *[256]byte, len *int) +TEXT ·xorKeyStreamVX(SB), NOSPLIT, $0 + MOVD $·constants<>(SB), R1 + MOVD dst+0(FP), R2 // R2=&dst[0] + LMG src+24(FP), R3, R4 // R3=&src[0] R4=len(src) + MOVD key+48(FP), R5 // R5=key + MOVD nonce+56(FP), R6 // R6=nonce + MOVD counter+64(FP), R7 // R7=counter + MOVD buf+72(FP), R8 // R8=buf + MOVD len+80(FP), R9 // R9=len + + // load BSWAP and J0 + VLM (R1), BSWAP, J0 + + // set up tail buffer + ADD $-1, R4, R12 + MOVBZ R12, R12 + CMPUBEQ R12, $255, aligned + MOVD R4, R1 + AND $~255, R1 + MOVD $(R3)(R1*1), R1 + EXRL $·mvcSrcToBuf(SB), R12 + MOVD $255, R0 + SUB R12, R0 + MOVD R0, (R9) // update len + +aligned: + // setup + MOVD $95, R0 + VLM (R5), KEY0, KEY1 + VLL R0, (R6), NONCE + VZERO M0 + VLEIB $7, $32, M0 + VSRLB M0, NONCE, NONCE + + // initialize counter values + VLREPF (R7), CTR + VZERO INC + VLEIF $1, $1, INC + VLEIF $2, $2, INC + VLEIF $3, $3, INC + VAF INC, CTR, CTR + VREPIF $4, INC + +chacha: + VREPF $0, J0, X0 + VREPF $1, J0, X1 + VREPF $2, J0, X2 + VREPF $3, J0, X3 + VREPF $0, KEY0, X4 + VREPF $1, KEY0, X5 + VREPF $2, KEY0, X6 + VREPF $3, KEY0, X7 + VREPF $0, KEY1, X8 + VREPF $1, KEY1, X9 + VREPF $2, KEY1, X10 + VREPF $3, KEY1, X11 + VLR CTR, X12 + VREPF $1, NONCE, X13 + VREPF $2, NONCE, X14 + VREPF $3, NONCE, X15 + + MOVD $(NUM_ROUNDS/2), R1 + +loop: + ROUND4(X0, X4, X12, X8, X1, X5, X13, X9, X2, X6, X14, X10, X3, X7, X15, X11) + ROUND4(X0, X5, X15, X10, X1, X6, X12, X11, X2, X7, X13, X8, X3, X4, X14, X9) + + ADD $-1, R1 + BNE loop + + // decrement length + ADD $-256, R4 + BLT tail + +continue: + // rearrange vectors + SHUFFLE(X0, X1, X2, X3, M0, M1, M2, M3) + ADDV(J0, X0, X1, X2, X3) + SHUFFLE(X4, X5, X6, X7, M0, M1, M2, M3) + ADDV(KEY0, X4, X5, X6, X7) + SHUFFLE(X8, X9, X10, X11, M0, M1, M2, M3) + ADDV(KEY1, X8, X9, X10, X11) + VAF CTR, X12, X12 + SHUFFLE(X12, X13, X14, X15, M0, M1, M2, M3) + ADDV(NONCE, X12, X13, X14, X15) + + // increment counters + VAF INC, CTR, CTR + + // xor keystream with plaintext + XORV(0*64, R2, R3, X0, X4, X8, X12) + XORV(1*64, R2, R3, X1, X5, X9, X13) + XORV(2*64, R2, R3, X2, X6, X10, X14) + XORV(3*64, R2, R3, X3, X7, X11, X15) + + // increment pointers + MOVD $256(R2), R2 + MOVD $256(R3), R3 + + CMPBNE R4, $0, chacha + CMPUBEQ R12, $255, return + EXRL $·mvcBufToDst(SB), R12 // len was updated during setup + +return: + VSTEF $0, CTR, (R7) + RET + +tail: + MOVD R2, R9 + MOVD R8, R2 + MOVD R8, R3 + MOVD $0, R4 + JMP continue + +// func hasVectorFacility() bool +TEXT ·hasVectorFacility(SB), NOSPLIT, $24-1 + MOVD $x-24(SP), R1 + XC $24, 0(R1), 0(R1) // clear the storage + MOVD $2, R0 // R0 is the number of double words stored -1 + WORD $0xB2B01000 // STFLE 0(R1) + XOR R0, R0 // reset the value of R0 + MOVBZ z-8(SP), R1 + AND $0x40, R1 + BEQ novector + +vectorinstalled: + // check if the vector instruction has been enabled + VLEIB $0, $0xF, V16 + VLGVB $0, V16, R1 + CMPBNE R1, $0xF, novector + MOVB $1, ret+0(FP) // have vx + RET + +novector: + MOVB $0, ret+0(FP) // no vx + RET |