| // 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 |
| } |
