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-rw-r--r--vendor/golang.org/x/crypto/internal/chacha20/asm_s390x.s283
-rw-r--r--vendor/golang.org/x/crypto/internal/chacha20/chacha_generic.go236
-rw-r--r--vendor/golang.org/x/crypto/internal/chacha20/chacha_noasm.go16
-rw-r--r--vendor/golang.org/x/crypto/internal/chacha20/chacha_s390x.go30
-rw-r--r--vendor/golang.org/x/crypto/internal/chacha20/xor.go43
-rw-r--r--vendor/golang.org/x/crypto/internal/subtle/aliasing.go32
-rw-r--r--vendor/golang.org/x/crypto/internal/subtle/aliasing_appengine.go35
7 files changed, 675 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
diff --git a/vendor/golang.org/x/crypto/internal/chacha20/chacha_generic.go b/vendor/golang.org/x/crypto/internal/chacha20/chacha_generic.go
new file mode 100644
index 0000000..523751f
--- /dev/null
+++ b/vendor/golang.org/x/crypto/internal/chacha20/chacha_generic.go
@@ -0,0 +1,236 @@
+// Copyright 2016 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.
+
+// Package ChaCha20 implements the core ChaCha20 function as specified
+// in https://tools.ietf.org/html/rfc7539#section-2.3.
+package chacha20
+
+import (
+ "crypto/cipher"
+ "encoding/binary"
+
+ "golang.org/x/crypto/internal/subtle"
+)
+
+// assert that *Cipher implements cipher.Stream
+var _ cipher.Stream = (*Cipher)(nil)
+
+// Cipher is a stateful instance of ChaCha20 using a particular key
+// and nonce. A *Cipher implements the cipher.Stream interface.
+type Cipher struct {
+ key [8]uint32
+ counter uint32 // incremented after each block
+ nonce [3]uint32
+ buf [bufSize]byte // buffer for unused keystream bytes
+ len int // number of unused keystream bytes at end of buf
+}
+
+// New creates a new ChaCha20 stream cipher with the given key and nonce.
+// The initial counter value is set to 0.
+func New(key [8]uint32, nonce [3]uint32) *Cipher {
+ return &Cipher{key: key, nonce: nonce}
+}
+
+// XORKeyStream XORs each byte in the given slice with a byte from the
+// cipher's key stream. Dst and src must overlap entirely or not at all.
+//
+// If len(dst) < len(src), XORKeyStream will panic. It is acceptable
+// to pass a dst bigger than src, and in that case, XORKeyStream will
+// only update dst[:len(src)] and will not touch the rest of dst.
+//
+// Multiple calls to XORKeyStream behave as if the concatenation of
+// the src buffers was passed in a single run. That is, Cipher
+// maintains state and does not reset at each XORKeyStream call.
+func (s *Cipher) XORKeyStream(dst, src []byte) {
+ if len(dst) < len(src) {
+ panic("chacha20: output smaller than input")
+ }
+ if subtle.InexactOverlap(dst[:len(src)], src) {
+ panic("chacha20: invalid buffer overlap")
+ }
+
+ // xor src with buffered keystream first
+ if s.len != 0 {
+ buf := s.buf[len(s.buf)-s.len:]
+ if len(src) < len(buf) {
+ buf = buf[:len(src)]
+ }
+ td, ts := dst[:len(buf)], src[:len(buf)] // BCE hint
+ for i, b := range buf {
+ td[i] = ts[i] ^ b
+ }
+ s.len -= len(buf)
+ if s.len != 0 {
+ return
+ }
+ s.buf = [len(s.buf)]byte{} // zero the empty buffer
+ src = src[len(buf):]
+ dst = dst[len(buf):]
+ }
+
+ if len(src) == 0 {
+ return
+ }
+ if haveAsm {
+ s.xorKeyStreamAsm(dst, src)
+ return
+ }
+
+ // set up a 64-byte buffer to pad out the final block if needed
+ // (hoisted out of the main loop to avoid spills)
+ rem := len(src) % 64 // length of final block
+ fin := len(src) - rem // index of final block
+ if rem > 0 {
+ copy(s.buf[len(s.buf)-64:], src[fin:])
+ }
+
+ // qr calculates a quarter round
+ qr := func(a, b, c, d uint32) (uint32, uint32, uint32, uint32) {
+ a += b
+ d ^= a
+ d = (d << 16) | (d >> 16)
+ c += d
+ b ^= c
+ b = (b << 12) | (b >> 20)
+ a += b
+ d ^= a
+ d = (d << 8) | (d >> 24)
+ c += d
+ b ^= c
+ b = (b << 7) | (b >> 25)
+ return a, b, c, d
+ }
+
+ // ChaCha20 constants
+ const (
+ j0 = 0x61707865
+ j1 = 0x3320646e
+ j2 = 0x79622d32
+ j3 = 0x6b206574
+ )
+
+ // pre-calculate most of the first round
+ s1, s5, s9, s13 := qr(j1, s.key[1], s.key[5], s.nonce[0])
+ s2, s6, s10, s14 := qr(j2, s.key[2], s.key[6], s.nonce[1])
+ s3, s7, s11, s15 := qr(j3, s.key[3], s.key[7], s.nonce[2])
+
+ n := len(src)
+ src, dst = src[:n:n], dst[:n:n] // BCE hint
+ for i := 0; i < n; i += 64 {
+ // calculate the remainder of the first round
+ s0, s4, s8, s12 := qr(j0, s.key[0], s.key[4], s.counter)
+
+ // execute the second round
+ x0, x5, x10, x15 := qr(s0, s5, s10, s15)
+ x1, x6, x11, x12 := qr(s1, s6, s11, s12)
+ x2, x7, x8, x13 := qr(s2, s7, s8, s13)
+ x3, x4, x9, x14 := qr(s3, s4, s9, s14)
+
+ // execute the remaining 18 rounds
+ for i := 0; i < 9; i++ {
+ x0, x4, x8, x12 = qr(x0, x4, x8, x12)
+ x1, x5, x9, x13 = qr(x1, x5, x9, x13)
+ x2, x6, x10, x14 = qr(x2, x6, x10, x14)
+ x3, x7, x11, x15 = qr(x3, x7, x11, x15)
+
+ x0, x5, x10, x15 = qr(x0, x5, x10, x15)
+ x1, x6, x11, x12 = qr(x1, x6, x11, x12)
+ x2, x7, x8, x13 = qr(x2, x7, x8, x13)
+ x3, x4, x9, x14 = qr(x3, x4, x9, x14)
+ }
+
+ x0 += j0
+ x1 += j1
+ x2 += j2
+ x3 += j3
+
+ x4 += s.key[0]
+ x5 += s.key[1]
+ x6 += s.key[2]
+ x7 += s.key[3]
+ x8 += s.key[4]
+ x9 += s.key[5]
+ x10 += s.key[6]
+ x11 += s.key[7]
+
+ x12 += s.counter
+ x13 += s.nonce[0]
+ x14 += s.nonce[1]
+ x15 += s.nonce[2]
+
+ // increment the counter
+ s.counter += 1
+ if s.counter == 0 {
+ panic("chacha20: counter overflow")
+ }
+
+ // pad to 64 bytes if needed
+ in, out := src[i:], dst[i:]
+ if i == fin {
+ // src[fin:] has already been copied into s.buf before
+ // the main loop
+ in, out = s.buf[len(s.buf)-64:], s.buf[len(s.buf)-64:]
+ }
+ in, out = in[:64], out[:64] // BCE hint
+
+ // XOR the key stream with the source and write out the result
+ xor(out[0:], in[0:], x0)
+ xor(out[4:], in[4:], x1)
+ xor(out[8:], in[8:], x2)
+ xor(out[12:], in[12:], x3)
+ xor(out[16:], in[16:], x4)
+ xor(out[20:], in[20:], x5)
+ xor(out[24:], in[24:], x6)
+ xor(out[28:], in[28:], x7)
+ xor(out[32:], in[32:], x8)
+ xor(out[36:], in[36:], x9)
+ xor(out[40:], in[40:], x10)
+ xor(out[44:], in[44:], x11)
+ xor(out[48:], in[48:], x12)
+ xor(out[52:], in[52:], x13)
+ xor(out[56:], in[56:], x14)
+ xor(out[60:], in[60:], x15)
+ }
+ // copy any trailing bytes out of the buffer and into dst
+ if rem != 0 {
+ s.len = 64 - rem
+ copy(dst[fin:], s.buf[len(s.buf)-64:])
+ }
+}
+
+// Advance discards bytes in the key stream until the next 64 byte block
+// boundary is reached and updates the counter accordingly. If the key
+// stream is already at a block boundary no bytes will be discarded and
+// the counter will be unchanged.
+func (s *Cipher) Advance() {
+ s.len -= s.len % 64
+ if s.len == 0 {
+ s.buf = [len(s.buf)]byte{}
+ }
+}
+
+// XORKeyStream crypts bytes from in to out using the given key and counters.
+// In and out must overlap entirely or not at all. Counter contains the raw
+// ChaCha20 counter bytes (i.e. block counter followed by nonce).
+func XORKeyStream(out, in []byte, counter *[16]byte, key *[32]byte) {
+ s := Cipher{
+ key: [8]uint32{
+ binary.LittleEndian.Uint32(key[0:4]),
+ binary.LittleEndian.Uint32(key[4:8]),
+ binary.LittleEndian.Uint32(key[8:12]),
+ binary.LittleEndian.Uint32(key[12:16]),
+ binary.LittleEndian.Uint32(key[16:20]),
+ binary.LittleEndian.Uint32(key[20:24]),
+ binary.LittleEndian.Uint32(key[24:28]),
+ binary.LittleEndian.Uint32(key[28:32]),
+ },
+ nonce: [3]uint32{
+ binary.LittleEndian.Uint32(counter[4:8]),
+ binary.LittleEndian.Uint32(counter[8:12]),
+ binary.LittleEndian.Uint32(counter[12:16]),
+ },
+ counter: binary.LittleEndian.Uint32(counter[0:4]),
+ }
+ s.XORKeyStream(out, in)
+}
diff --git a/vendor/golang.org/x/crypto/internal/chacha20/chacha_noasm.go b/vendor/golang.org/x/crypto/internal/chacha20/chacha_noasm.go
new file mode 100644
index 0000000..91520d1
--- /dev/null
+++ b/vendor/golang.org/x/crypto/internal/chacha20/chacha_noasm.go
@@ -0,0 +1,16 @@
+// 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
+
+package chacha20
+
+const (
+ bufSize = 64
+ haveAsm = false
+)
+
+func (*Cipher) xorKeyStreamAsm(dst, src []byte) {
+ panic("not implemented")
+}
diff --git a/vendor/golang.org/x/crypto/internal/chacha20/chacha_s390x.go b/vendor/golang.org/x/crypto/internal/chacha20/chacha_s390x.go
new file mode 100644
index 0000000..0c1c671
--- /dev/null
+++ b/vendor/golang.org/x/crypto/internal/chacha20/chacha_s390x.go
@@ -0,0 +1,30 @@
+// 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
+
+package chacha20
+
+var haveAsm = hasVectorFacility()
+
+const bufSize = 256
+
+// hasVectorFacility reports whether the machine supports the vector
+// facility (vx).
+// Implementation in asm_s390x.s.
+func hasVectorFacility() bool
+
+// xorKeyStreamVX is an assembly implementation of XORKeyStream. It must only
+// be called when the vector facility is available.
+// Implementation in asm_s390x.s.
+//go:noescape
+func xorKeyStreamVX(dst, src []byte, key *[8]uint32, nonce *[3]uint32, counter *uint32, buf *[256]byte, len *int)
+
+func (c *Cipher) xorKeyStreamAsm(dst, src []byte) {
+ xorKeyStreamVX(dst, src, &c.key, &c.nonce, &c.counter, &c.buf, &c.len)
+}
+
+// EXRL targets, DO NOT CALL!
+func mvcSrcToBuf()
+func mvcBufToDst()
diff --git a/vendor/golang.org/x/crypto/internal/chacha20/xor.go b/vendor/golang.org/x/crypto/internal/chacha20/xor.go
new file mode 100644
index 0000000..9c5ba0b
--- /dev/null
+++ b/vendor/golang.org/x/crypto/internal/chacha20/xor.go
@@ -0,0 +1,43 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found src the LICENSE file.
+
+package chacha20
+
+import (
+ "runtime"
+)
+
+// Platforms that have fast unaligned 32-bit little endian accesses.
+const unaligned = runtime.GOARCH == "386" ||
+ runtime.GOARCH == "amd64" ||
+ runtime.GOARCH == "arm64" ||
+ runtime.GOARCH == "ppc64le" ||
+ runtime.GOARCH == "s390x"
+
+// xor reads a little endian uint32 from src, XORs it with u and
+// places the result in little endian byte order in dst.
+func xor(dst, src []byte, u uint32) {
+ _, _ = src[3], dst[3] // eliminate bounds checks
+ if unaligned {
+ // The compiler should optimize this code into
+ // 32-bit unaligned little endian loads and stores.
+ // TODO: delete once the compiler does a reliably
+ // good job with the generic code below.
+ // See issue #25111 for more details.
+ v := uint32(src[0])
+ v |= uint32(src[1]) << 8
+ v |= uint32(src[2]) << 16
+ v |= uint32(src[3]) << 24
+ v ^= u
+ dst[0] = byte(v)
+ dst[1] = byte(v >> 8)
+ dst[2] = byte(v >> 16)
+ dst[3] = byte(v >> 24)
+ } else {
+ dst[0] = src[0] ^ byte(u)
+ dst[1] = src[1] ^ byte(u>>8)
+ dst[2] = src[2] ^ byte(u>>16)
+ dst[3] = src[3] ^ byte(u>>24)
+ }
+}
diff --git a/vendor/golang.org/x/crypto/internal/subtle/aliasing.go b/vendor/golang.org/x/crypto/internal/subtle/aliasing.go
new file mode 100644
index 0000000..f38797b
--- /dev/null
+++ b/vendor/golang.org/x/crypto/internal/subtle/aliasing.go
@@ -0,0 +1,32 @@
+// 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 !appengine
+
+// Package subtle implements functions that are often useful in cryptographic
+// code but require careful thought to use correctly.
+package subtle // import "golang.org/x/crypto/internal/subtle"
+
+import "unsafe"
+
+// AnyOverlap reports whether x and y share memory at any (not necessarily
+// corresponding) index. The memory beyond the slice length is ignored.
+func AnyOverlap(x, y []byte) bool {
+ return len(x) > 0 && len(y) > 0 &&
+ uintptr(unsafe.Pointer(&x[0])) <= uintptr(unsafe.Pointer(&y[len(y)-1])) &&
+ uintptr(unsafe.Pointer(&y[0])) <= uintptr(unsafe.Pointer(&x[len(x)-1]))
+}
+
+// InexactOverlap reports whether x and y share memory at any non-corresponding
+// index. The memory beyond the slice length is ignored. Note that x and y can
+// have different lengths and still not have any inexact overlap.
+//
+// InexactOverlap can be used to implement the requirements of the crypto/cipher
+// AEAD, Block, BlockMode and Stream interfaces.
+func InexactOverlap(x, y []byte) bool {
+ if len(x) == 0 || len(y) == 0 || &x[0] == &y[0] {
+ return false
+ }
+ return AnyOverlap(x, y)
+}
diff --git a/vendor/golang.org/x/crypto/internal/subtle/aliasing_appengine.go b/vendor/golang.org/x/crypto/internal/subtle/aliasing_appengine.go
new file mode 100644
index 0000000..0cc4a8a
--- /dev/null
+++ b/vendor/golang.org/x/crypto/internal/subtle/aliasing_appengine.go
@@ -0,0 +1,35 @@
+// 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 appengine
+
+// Package subtle implements functions that are often useful in cryptographic
+// code but require careful thought to use correctly.
+package subtle // import "golang.org/x/crypto/internal/subtle"
+
+// This is the Google App Engine standard variant based on reflect
+// because the unsafe package and cgo are disallowed.
+
+import "reflect"
+
+// AnyOverlap reports whether x and y share memory at any (not necessarily
+// corresponding) index. The memory beyond the slice length is ignored.
+func AnyOverlap(x, y []byte) bool {
+ return len(x) > 0 && len(y) > 0 &&
+ reflect.ValueOf(&x[0]).Pointer() <= reflect.ValueOf(&y[len(y)-1]).Pointer() &&
+ reflect.ValueOf(&y[0]).Pointer() <= reflect.ValueOf(&x[len(x)-1]).Pointer()
+}
+
+// InexactOverlap reports whether x and y share memory at any non-corresponding
+// index. The memory beyond the slice length is ignored. Note that x and y can
+// have different lengths and still not have any inexact overlap.
+//
+// InexactOverlap can be used to implement the requirements of the crypto/cipher
+// AEAD, Block, BlockMode and Stream interfaces.
+func InexactOverlap(x, y []byte) bool {
+ if len(x) == 0 || len(y) == 0 || &x[0] == &y[0] {
+ return false
+ }
+ return AnyOverlap(x, y)
+}