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Diffstat (limited to 'vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.go')
-rw-r--r--vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.go80
1 files changed, 80 insertions, 0 deletions
diff --git a/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.go b/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.go
new file mode 100644
index 000000000..475503321
--- /dev/null
+++ b/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.go
@@ -0,0 +1,80 @@
+// 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.
+
+// +build go1.7,amd64,!gccgo,!appengine
+
+package chacha20poly1305
+
+import "encoding/binary"
+
+//go:noescape
+func chacha20Poly1305Open(dst []byte, key []uint32, src, ad []byte) bool
+
+//go:noescape
+func chacha20Poly1305Seal(dst []byte, key []uint32, src, ad []byte)
+
+//go:noescape
+func haveSSSE3() bool
+
+var canUseASM bool
+
+func init() {
+ canUseASM = haveSSSE3()
+}
+
+// setupState writes a ChaCha20 input matrix to state. See
+// https://tools.ietf.org/html/rfc7539#section-2.3.
+func setupState(state *[16]uint32, key *[32]byte, nonce []byte) {
+ state[0] = 0x61707865
+ state[1] = 0x3320646e
+ state[2] = 0x79622d32
+ state[3] = 0x6b206574
+
+ state[4] = binary.LittleEndian.Uint32(key[:4])
+ state[5] = binary.LittleEndian.Uint32(key[4:8])
+ state[6] = binary.LittleEndian.Uint32(key[8:12])
+ state[7] = binary.LittleEndian.Uint32(key[12:16])
+ state[8] = binary.LittleEndian.Uint32(key[16:20])
+ state[9] = binary.LittleEndian.Uint32(key[20:24])
+ state[10] = binary.LittleEndian.Uint32(key[24:28])
+ state[11] = binary.LittleEndian.Uint32(key[28:32])
+
+ state[12] = 0
+ state[13] = binary.LittleEndian.Uint32(nonce[:4])
+ state[14] = binary.LittleEndian.Uint32(nonce[4:8])
+ state[15] = binary.LittleEndian.Uint32(nonce[8:12])
+}
+
+func (c *chacha20poly1305) seal(dst, nonce, plaintext, additionalData []byte) []byte {
+ if !canUseASM {
+ return c.sealGeneric(dst, nonce, plaintext, additionalData)
+ }
+
+ var state [16]uint32
+ setupState(&state, &c.key, nonce)
+
+ ret, out := sliceForAppend(dst, len(plaintext)+16)
+ chacha20Poly1305Seal(out[:], state[:], plaintext, additionalData)
+ return ret
+}
+
+func (c *chacha20poly1305) open(dst, nonce, ciphertext, additionalData []byte) ([]byte, error) {
+ if !canUseASM {
+ return c.openGeneric(dst, nonce, ciphertext, additionalData)
+ }
+
+ var state [16]uint32
+ setupState(&state, &c.key, nonce)
+
+ ciphertext = ciphertext[:len(ciphertext)-16]
+ ret, out := sliceForAppend(dst, len(ciphertext))
+ if !chacha20Poly1305Open(out, state[:], ciphertext, additionalData) {
+ for i := range out {
+ out[i] = 0
+ }
+ return nil, errOpen
+ }
+
+ return ret, nil
+}