| // Copyright 2016 The BoringSSL Authors | |
| // | |
| // Licensed under the Apache License, Version 2.0 (the "License"); | |
| // you may not use this file except in compliance with the License. | |
| // You may obtain a copy of the License at | |
| // | |
| // https://www.apache.org/licenses/LICENSE-2.0 | |
| // | |
| // Unless required by applicable law or agreed to in writing, software | |
| // distributed under the License is distributed on an "AS IS" BASIS, | |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
| // See the License for the specific language governing permissions and | |
| // limitations under the License. | |
| package runner | |
| import ( | |
| "encoding/binary" | |
| "golang.org/x/crypto/chacha20" | |
| ) | |
| // Use a different key from crypto/rand/deterministic.c. | |
| var deterministicRandKey = []byte("runner deterministic key 0123456") | |
| type deterministicRand struct { | |
| numCalls uint64 | |
| } | |
| func (d *deterministicRand) Read(buf []byte) (int, error) { | |
| clear(buf) | |
| var nonce [12]byte | |
| binary.LittleEndian.PutUint64(nonce[:8], d.numCalls) | |
| cipher, err := chacha20.NewUnauthenticatedCipher(deterministicRandKey, nonce[:]) | |
| if err != nil { | |
| return 0, err | |
| } | |
| cipher.XORKeyStream(buf, buf) | |
| d.numCalls++ | |
| return len(buf), nil | |
| } |