1// Copyright 2016 The BoringSSL Authors 2// 3// Permission to use, copy, modify, and/or distribute this software for any 4// purpose with or without fee is hereby granted, provided that the above 5// copyright notice and this permission notice appear in all copies. 6// 7// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 8// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 9// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 10// SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 11// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION 12// OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN 13// CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 14 15package runner 16 17import ( 18 "encoding/binary" 19 20 "golang.org/x/crypto/chacha20" 21) 22 23// Use a different key from crypto/rand/deterministic.c. 24var deterministicRandKey = []byte("runner deterministic key 0123456") 25 26type deterministicRand struct { 27 numCalls uint64 28} 29 30func (d *deterministicRand) Read(buf []byte) (int, error) { 31 clear(buf) 32 var nonce [12]byte 33 binary.LittleEndian.PutUint64(nonce[:8], d.numCalls) 34 cipher, err := chacha20.NewUnauthenticatedCipher(deterministicRandKey, nonce[:]) 35 if err != nil { 36 return 0, err 37 } 38 cipher.XORKeyStream(buf, buf) 39 d.numCalls++ 40 return len(buf), nil 41} 42