1 files changed, 155 insertions, 0 deletions
diff --git a/vendor/golang.org/x/crypto/internal/chacha20/chacha_test.go b/vendor/golang.org/x/crypto/internal/chacha20/chacha_test.go
index b80d34c..bf99330 100644
--- a/vendor/golang.org/x/crypto/internal/chacha20/chacha_test.go
+++ b/vendor/golang.org/x/crypto/internal/chacha20/chacha_test.go
@@ -6,6 +6,8 @@ package chacha20
 
 import (
 	"encoding/hex"
+	"fmt"
+	"math/rand"
 	"testing"
 )
 
@@ -31,3 +33,156 @@ func TestCore(t *testing.T) {
 		t.Errorf("wanted %x but got %x", expected, result)
 	}
 }
+
+// Run the test cases with the input and output in different buffers.
+func TestNoOverlap(t *testing.T) {
+	for _, c := range testVectors {
+		s := New(c.key, c.nonce)
+		input, err := hex.DecodeString(c.input)
+		if err != nil {
+			t.Fatalf("cannot decode input %#v: %v", c.input, err)
+		}
+		output := make([]byte, c.length)
+		s.XORKeyStream(output, input)
+		got := hex.EncodeToString(output)
+		if got != c.output {
+			t.Errorf("length=%v: got %#v, want %#v", c.length, got, c.output)
+		}
+	}
+}
+
+// Run the test cases with the input and output overlapping entirely.
+func TestOverlap(t *testing.T) {
+	for _, c := range testVectors {
+		s := New(c.key, c.nonce)
+		data, err := hex.DecodeString(c.input)
+		if err != nil {
+			t.Fatalf("cannot decode input %#v: %v", c.input, err)
+		}
+		s.XORKeyStream(data, data)
+		got := hex.EncodeToString(data)
+		if got != c.output {
+			t.Errorf("length=%v: got %#v, want %#v", c.length, got, c.output)
+		}
+	}
+}
+
+// Run the test cases with various source and destination offsets.
+func TestUnaligned(t *testing.T) {
+	const max = 8 // max offset (+1) to test
+	for _, c := range testVectors {
+		input := make([]byte, c.length+max)
+		output := make([]byte, c.length+max)
+		for i := 0; i < max; i++ { // input offsets
+			for j := 0; j < max; j++ { // output offsets
+				s := New(c.key, c.nonce)
+
+				input := input[i : i+c.length]
+				output := output[j : j+c.length]
+
+				data, err := hex.DecodeString(c.input)
+				if err != nil {
+					t.Fatalf("cannot decode input %#v: %v", c.input, err)
+				}
+				copy(input, data)
+				s.XORKeyStream(output, input)
+				got := hex.EncodeToString(output)
+				if got != c.output {
+					t.Errorf("length=%v: got %#v, want %#v", c.length, got, c.output)
+				}
+			}
+		}
+	}
+}
+
+// Run the test cases by calling XORKeyStream multiple times.
+func TestStep(t *testing.T) {
+	// wide range of step sizes to try and hit edge cases
+	steps := [...]int{1, 3, 4, 7, 8, 17, 24, 30, 64, 256}
+	rnd := rand.New(rand.NewSource(123))
+	for _, c := range testVectors {
+		s := New(c.key, c.nonce)
+		input, err := hex.DecodeString(c.input)
+		if err != nil {
+			t.Fatalf("cannot decode input %#v: %v", c.input, err)
+		}
+		output := make([]byte, c.length)
+
+		// step through the buffers
+		i, step := 0, steps[rnd.Intn(len(steps))]
+		for i+step < c.length {
+			s.XORKeyStream(output[i:i+step], input[i:i+step])
+			if i+step < c.length && output[i+step] != 0 {
+				t.Errorf("length=%v, i=%v, step=%v: output overwritten", c.length, i, step)
+			}
+			i += step
+			step = steps[rnd.Intn(len(steps))]
+		}
+		// finish the encryption
+		s.XORKeyStream(output[i:], input[i:])
+
+		got := hex.EncodeToString(output)
+		if got != c.output {
+			t.Errorf("length=%v: got %#v, want %#v", c.length, got, c.output)
+		}
+	}
+}
+
+// Test that Advance() discards bytes until a block boundary is hit.
+func TestAdvance(t *testing.T) {
+	for _, c := range testVectors {
+		for i := 0; i < 63; i++ {
+			s := New(c.key, c.nonce)
+			z := New(c.key, c.nonce)
+			input, err := hex.DecodeString(c.input)
+			if err != nil {
+				t.Fatalf("cannot decode input %#v: %v", c.input, err)
+			}
+			zeros, discard := make([]byte, 64), make([]byte, 64)
+			so, zo := make([]byte, c.length), make([]byte, c.length)
+			for j := 0; j < c.length; j += 64 {
+				lim := j + i
+				if lim > c.length {
+					lim = c.length
+				}
+				s.XORKeyStream(so[j:lim], input[j:lim])
+				// calling s.Advance() multiple times should have no effect
+				for k := 0; k < i%3+1; k++ {
+					s.Advance()
+				}
+				z.XORKeyStream(zo[j:lim], input[j:lim])
+				if lim < c.length {
+					end := 64 - i
+					if c.length-lim < end {
+						end = c.length - lim
+					}
+					z.XORKeyStream(discard[:], zeros[:end])
+				}
+			}
+
+			got := hex.EncodeToString(so)
+			want := hex.EncodeToString(zo)
+			if got != want {
+				t.Errorf("length=%v: got %#v, want %#v", c.length, got, want)
+			}
+		}
+	}
+}
+
+func BenchmarkChaCha20(b *testing.B) {
+	sizes := []int{32, 63, 64, 256, 1024, 1350, 65536}
+	for _, size := range sizes {
+		s := size
+		b.Run(fmt.Sprint(s), func(b *testing.B) {
+			k := [32]byte{}
+			c := [16]byte{}
+			src := make([]byte, s)
+			dst := make([]byte, s)
+			b.SetBytes(int64(s))
+			b.ResetTimer()
+			for i := 0; i < b.N; i++ {
+				XORKeyStream(dst, src, &c, &k)
+			}
+		})
+	}
+}