initial import

vendor/github.com/wg/ecies/xchacha20poly1305/xchacha20poly1305.go

@@ -0,0 +1,75 @@
+// Copyright (C) 2016 - Will Glozer. All rights reserved.
+
+// Package xchacha20poly1305 implements an AEAD construction
+// similar to NaCl's xsalsa20poly1305 secretbox, but using
+// XChaCha20 instead of XSalsa20.
+package xchacha20poly1305
+
+import (
+	"schwanenlied.me/yawning/chacha20"
+	"schwanenlied.me/yawning/poly1305"
+)
+
+const (
+	KeySize   = chacha20.KeySize
+	NonceSize = chacha20.XNonceSize
+	TagSize   = poly1305.Size
+)
+
+type XChaCha20Poly1305 struct {
+	chacha20.Cipher
+	poly1305.Poly1305
+}
+
+func New(key *[KeySize]byte, nonce *[NonceSize]byte) *XChaCha20Poly1305 {
+	x := &XChaCha20Poly1305{}
+	x.Init(key[:], nonce[:])
+	return x
+}
+
+func (x *XChaCha20Poly1305) Init(key, nonce []byte) error {
+	err := x.ReKey(key, nonce)
+	if err == nil {
+		x.initPoly1305()
+		x.Seek(1)
+	}
+	return err
+}
+
+func (x *XChaCha20Poly1305) Auth(src []byte) {
+	if len(src) > 0 {
+		x.Poly1305.Write(src)
+	}
+}
+
+func (x *XChaCha20Poly1305) Decrypt(dst, src []byte) {
+	x.Poly1305.Write(src)
+	x.XORKeyStream(dst, src)
+}
+
+func (x *XChaCha20Poly1305) Encrypt(dst, src []byte) {
+	n := len(src)
+	x.XORKeyStream(dst, src)
+	x.Poly1305.Write(dst[:n])
+}
+
+func (x *XChaCha20Poly1305) Tag(b []byte) []byte {
+	return x.Poly1305.Sum(b)
+}
+
+func (x *XChaCha20Poly1305) Reset() {
+	x.Cipher.Reset()
+}
+
+func (x *XChaCha20Poly1305) TagSize() int {
+	return TagSize
+}
+
+func (x *XChaCha20Poly1305) initPoly1305() {
+	var key [poly1305.KeySize]byte
+	x.KeyStream(key[:])
+	x.Poly1305.Init(key[:])
+	for i := range key {
+		key[i] = 0
+	}
+}

vendor/github.com/wg/ecies/xchacha20poly1305/xchacha20poly1305_test.go

@@ -0,0 +1,65 @@
+// Copyright (C) 2016 - Will Glozer. All rights reserved.
+
+package xchacha20poly1305
+
+import (
+	"bytes"
+	"testing"
+)
+
+// plaintext & key from RFC 7539 with the 12-byte nonce repeated twice and
+// expected ciphertext derived from the SUPERCOP chacha20 reference impl.
+func TestXChaCha20(t *testing.T) {
+	plaintext := []byte{
+		0x4c, 0x61, 0x64, 0x69, 0x65, 0x73, 0x20, 0x61, 0x6e, 0x64, 0x20, 0x47, 0x65, 0x6e, 0x74, 0x6c,
+		0x65, 0x6d, 0x65, 0x6e, 0x20, 0x6f, 0x66, 0x20, 0x74, 0x68, 0x65, 0x20, 0x63, 0x6c, 0x61, 0x73,
+		0x73, 0x20, 0x6f, 0x66, 0x20, 0x27, 0x39, 0x39, 0x3a, 0x20, 0x49, 0x66, 0x20, 0x49, 0x20, 0x63,
+		0x6f, 0x75, 0x6c, 0x64, 0x20, 0x6f, 0x66, 0x66, 0x65, 0x72, 0x20, 0x79, 0x6f, 0x75, 0x20, 0x6f,
+		0x6e, 0x6c, 0x79, 0x20, 0x6f, 0x6e, 0x65, 0x20, 0x74, 0x69, 0x70, 0x20, 0x66, 0x6f, 0x72, 0x20,
+		0x74, 0x68, 0x65, 0x20, 0x66, 0x75, 0x74, 0x75, 0x72, 0x65, 0x2c, 0x20, 0x73, 0x75, 0x6e, 0x73,
+		0x63, 0x72, 0x65, 0x65, 0x6e, 0x20, 0x77, 0x6f, 0x75, 0x6c, 0x64, 0x20, 0x62, 0x65, 0x20, 0x69,
+		0x74, 0x2e,
+	}
+
+	key := []byte{
+		0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
+		0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
+	}
+
+	nonce := []byte{
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x4a, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x4a, 0x00, 0x00, 0x00, 0x00,
+	}
+
+	ciphertext := []byte{
+		0x15, 0x62, 0x3c, 0xe5, 0x14, 0x3a, 0xd8, 0xc8, 0x46, 0x79, 0x0b, 0xc3, 0x8c, 0x5e, 0x81, 0x50,
+		0x85, 0x1c, 0xd4, 0xa5, 0x30, 0xf5, 0xfa, 0xb8, 0x02, 0xe6, 0x1e, 0x87, 0x52, 0x91, 0x57, 0x9f,
+		0x40, 0x0b, 0x2c, 0x57, 0x79, 0x95, 0xdf, 0x0c, 0xbc, 0xd9, 0x71, 0x30, 0x30, 0xad, 0x64, 0xee,
+		0x93, 0x7d, 0xd2, 0xfa, 0x5c, 0x48, 0xff, 0xda, 0x7c, 0x91, 0xd1, 0x5b, 0xc3, 0x41, 0x3e, 0x33,
+		0x55, 0x1d, 0x10, 0x97, 0x73, 0x0e, 0x40, 0x51, 0x4a, 0x1f, 0xf9, 0x04, 0xee, 0xb0, 0xe6, 0xd2,
+		0x2a, 0x42, 0x79, 0xc0, 0xee, 0xe1, 0xb4, 0x92, 0x9c, 0x5a, 0xe4, 0x24, 0x21, 0xe0, 0x0f, 0x3e,
+		0x3b, 0xa3, 0x0c, 0x7b, 0x7a, 0xa3, 0xfa, 0x0f, 0x9d, 0x7b, 0x69, 0xc4, 0x7f, 0xdf, 0x6d, 0xe5,
+		0x35, 0xa3,
+	}
+
+	tag := []byte{
+		0x80, 0xdf, 0x98, 0xf1, 0xff, 0x1d, 0xc9, 0xc8, 0xdd, 0x08, 0xeb, 0xf8, 0x45, 0x1c, 0x8b, 0xd2,
+	}
+
+	c := XChaCha20Poly1305{}
+
+	err := c.Init(key, nonce)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	c.Encrypt(plaintext, plaintext)
+
+	if !bytes.Equal(plaintext, ciphertext) {
+		t.Fatal("encrypted plaintext != expected ciphertext")
+	}
+
+	if !bytes.Equal(c.Tag(nil), tag) {
+		t.Fatal("actual tag != expected tag")
+	}
+}