1 files changed, 46 insertions, 0 deletions
diff --git a/src/math/rand/v2/chacha8.go b/src/math/rand/v2/chacha8.go
new file mode 100644
index 0000000..6b9aa72
--- /dev/null
+++ b/src/math/rand/v2/chacha8.go
@@ -0,0 +1,46 @@
+// Copyright 2023 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 rand
+
+import "internal/chacha8rand"
+
+// A ChaCha8 is a ChaCha8-based cryptographically strong
+// random number generator.
+type ChaCha8 struct {
+	state chacha8rand.State
+}
+
+// NewChaCha8 returns a new ChaCha8 seeded with the given seed.
+func NewChaCha8(seed [32]byte) *ChaCha8 {
+	c := new(ChaCha8)
+	c.state.Init(seed)
+	return c
+}
+
+// Seed resets the ChaCha8 to behave the same way as NewChaCha8(seed).
+func (c *ChaCha8) Seed(seed [32]byte) {
+	c.state.Init(seed)
+}
+
+// Uint64 returns a uniformly distributed random uint64 value.
+func (c *ChaCha8) Uint64() uint64 {
+	for {
+		x, ok := c.state.Next()
+		if ok {
+			return x
+		}
+		c.state.Refill()
+	}
+}
+
+// UnmarshalBinary implements the encoding.BinaryUnmarshaler interface.
+func (c *ChaCha8) UnmarshalBinary(data []byte) error {
+	return chacha8rand.Unmarshal(&c.state, data)
+}
+
+// MarshalBinary implements the encoding.BinaryMarshaler interface.
+func (c *ChaCha8) MarshalBinary() ([]byte, error) {
+	return chacha8rand.Marshal(&c.state), nil
+}