1 // Copyright (c) 2016, Google Inc. 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 15 package runner 16 17 import ( 18 "encoding/binary" 19 ) 20 21 // Use a different key from crypto/rand/deterministic.c. 22 var deterministicRandKey = []byte("runner deterministic key 0123456") 23 24 type deterministicRand struct { 25 numCalls uint64 26 } 27 28 func (d *deterministicRand) Read(buf []byte) (int, error) { 29 for i := range buf { 30 buf[i] = 0 31 } 32 var nonce [12]byte 33 binary.LittleEndian.PutUint64(nonce[:8], d.numCalls) 34 chaCha20(buf, buf, deterministicRandKey, nonce[:], 0) 35 d.numCalls++ 36 return len(buf), nil 37 } 38
