From 8423f6ef5a7fd29bd76636cc16702911d246b4b1 Mon Sep 17 00:00:00 2001
From: Zaki Manian <zaki@manian.org>
Date: Mon, 21 May 2018 20:45:36 -0700
Subject: [PATCH] Add the libsodium test vector

---
 xchacha20poly1035/xchachapoly.go      |  8 +--
 xchacha20poly1035/xchachapoly_test.go | 91 +++++++++++++++++++++++++++
 2 files changed, 95 insertions(+), 4 deletions(-)
 create mode 100644 xchacha20poly1035/xchachapoly_test.go

diff --git a/xchacha20poly1035/xchachapoly.go b/xchacha20poly1035/xchachapoly.go
index b9d823414..96413b8c1 100644
--- a/xchacha20poly1035/xchachapoly.go
+++ b/xchacha20poly1035/xchachapoly.go
@@ -41,11 +41,11 @@ func (c *xchacha20poly1305) Overhead() int {
 
 func (c *xchacha20poly1305) Seal(dst, nonce, plaintext, additionalData []byte) []byte {
 	if len(nonce) != NonceSize {
-		panic("chacha20poly1305: bad nonce length passed to Seal")
+		panic("xchacha20poly1305: bad nonce length passed to Seal")
 	}
 
 	if uint64(len(plaintext)) > (1<<38)-64 {
-		panic("chacha20poly1305: plaintext too large")
+		panic("xchacha20poly1305: plaintext too large")
 	}
 
 	var subKey [KeySize]byte
@@ -64,10 +64,10 @@ func (c *xchacha20poly1305) Seal(dst, nonce, plaintext, additionalData []byte) [
 
 func (c *xchacha20poly1305) Open(dst, nonce, ciphertext, additionalData []byte) ([]byte, error) {
 	if len(nonce) != NonceSize {
-		panic("chacha20poly1305: bad nonce length passed to Open")
+		panic("xchacha20poly1305: bad nonce length passed to Open")
 	}
 	if uint64(len(ciphertext)) > (1<<38)-48 {
-		panic("chacha20poly1305: ciphertext too large")
+		panic("xchacha20poly1305: ciphertext too large")
 	}
 	var subKey [KeySize]byte
 	var hNonce [16]byte
diff --git a/xchacha20poly1035/xchachapoly_test.go b/xchacha20poly1035/xchachapoly_test.go
new file mode 100644
index 000000000..5e522e0b1
--- /dev/null
+++ b/xchacha20poly1035/xchachapoly_test.go
@@ -0,0 +1,91 @@
+package xchacha20poly1305
+
+import (
+	"bytes"
+	"encoding/hex"
+	"testing"
+)
+
+func toHex(bits []byte) string {
+	return hex.EncodeToString(bits)
+}
+
+func fromHex(bits string) []byte {
+	b, err := hex.DecodeString(bits)
+	if err != nil {
+		panic(err)
+	}
+	return b
+}
+
+func TestHChaCha20(t *testing.T) {
+	for i, v := range hChaCha20Vectors {
+		var key [32]byte
+		var nonce [16]byte
+		copy(key[:], v.key)
+		copy(nonce[:], v.nonce)
+
+		HChaCha20(&key, &nonce, &key)
+		if !bytes.Equal(key[:], v.keystream) {
+			t.Errorf("Test %d: keystream mismatch:\n \t got:  %s\n \t want: %s", i, toHex(key[:]), toHex(v.keystream))
+		}
+	}
+}
+
+var hChaCha20Vectors = []struct {
+	key, nonce, keystream []byte
+}{
+	{
+		fromHex("0000000000000000000000000000000000000000000000000000000000000000"),
+		fromHex("000000000000000000000000000000000000000000000000"),
+		fromHex("1140704c328d1d5d0e30086cdf209dbd6a43b8f41518a11cc387b669b2ee6586"),
+	},
+	{
+		fromHex("8000000000000000000000000000000000000000000000000000000000000000"),
+		fromHex("000000000000000000000000000000000000000000000000"),
+		fromHex("7d266a7fd808cae4c02a0a70dcbfbcc250dae65ce3eae7fc210f54cc8f77df86"),
+	},
+	{
+		fromHex("0000000000000000000000000000000000000000000000000000000000000001"),
+		fromHex("000000000000000000000000000000000000000000000002"),
+		fromHex("e0c77ff931bb9163a5460c02ac281c2b53d792b1c43fea817e9ad275ae546963"),
+	},
+	{
+		fromHex("000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f"),
+		fromHex("000102030405060708090a0b0c0d0e0f1011121314151617"),
+		fromHex("51e3ff45a895675c4b33b46c64f4a9ace110d34df6a2ceab486372bacbd3eff6"),
+	},
+}
+
+func TestVectors(t *testing.T) {
+	for i, v := range vectors {
+		if len(v.plaintext) == 0 {
+			v.plaintext = make([]byte, len(v.ciphertext))
+		}
+
+		var nonce [24]byte
+		copy(nonce[:], v.nonce)
+
+		aead, err := New(v.key)
+		if err != nil {
+			t.Error(err)
+		}
+
+		dst := aead.Seal(nil, nonce[:], v.plaintext, v.ad)
+		if !bytes.Equal(dst, v.ciphertext) {
+			t.Errorf("Test %d: ciphertext mismatch:\n \t got:  %s\n \t want: %s", i, toHex(dst), toHex(v.ciphertext))
+		}
+	}
+}
+
+var vectors = []struct {
+	key, nonce, ad, plaintext, ciphertext []byte
+}{
+	{
+		[]byte{0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f},
+		[]byte{0x07, 0x00, 0x00, 0x00, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a, 0x4b},
+		[]byte{0x50, 0x51, 0x52, 0x53, 0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7},
+		[]byte("Ladies and Gentlemen of the class of '99: If I could offer you only one tip for the future, sunscreen would be it."),
+		[]byte{0x45, 0x3c, 0x06, 0x93, 0xa7, 0x40, 0x7f, 0x04, 0xff, 0x4c, 0x56, 0xae, 0xdb, 0x17, 0xa3, 0xc0, 0xa1, 0xaf, 0xff, 0x01, 0x17, 0x49, 0x30, 0xfc, 0x22, 0x28, 0x7c, 0x33, 0xdb, 0xcf, 0x0a, 0xc8, 0xb8, 0x9a, 0xd9, 0x29, 0x53, 0x0a, 0x1b, 0xb3, 0xab, 0x5e, 0x69, 0xf2, 0x4c, 0x7f, 0x60, 0x70, 0xc8, 0xf8, 0x40, 0xc9, 0xab, 0xb4, 0xf6, 0x9f, 0xbf, 0xc8, 0xa7, 0xff, 0x51, 0x26, 0xfa, 0xee, 0xbb, 0xb5, 0x58, 0x05, 0xee, 0x9c, 0x1c, 0xf2, 0xce, 0x5a, 0x57, 0x26, 0x32, 0x87, 0xae, 0xc5, 0x78, 0x0f, 0x04, 0xec, 0x32, 0x4c, 0x35, 0x14, 0x12, 0x2c, 0xfc, 0x32, 0x31, 0xfc, 0x1a, 0x8b, 0x71, 0x8a, 0x62, 0x86, 0x37, 0x30, 0xa2, 0x70, 0x2b, 0xb7, 0x63, 0x66, 0x11, 0x6b, 0xed, 0x09, 0xe0, 0xfd, 0x5c, 0x6d, 0x84, 0xb6, 0xb0, 0xc1, 0xab, 0xaf, 0x24, 0x9d, 0x5d, 0xd0, 0xf7, 0xf5, 0xa7, 0xea},
+	},
+}