func FillWithFakeDoubles(dest [][]byte, nonce *[24]byte, nextKeys []*[32]byte) {
ParallelFor(len(dest)/2, func(p *P) {
for i, ok := p.Next(); ok; i, ok = p.Next() {
var exchange1 [SizeConvoExchange]byte
var exchange2 [SizeConvoExchange]byte
rand.Read(exchange1[:])
copy(exchange2[0:16], exchange1[0:16])
rand.Read(exchange2[16:])
onion1, _ := onionbox.Seal(exchange1[:], nonce, nextKeys)
onion2, _ := onionbox.Seal(exchange2[:], nonce, nextKeys)
dest[i*2] = onion1
dest[i*2+1] = onion2
}
})
}
func (srv *ConvoService) Get(args *ConvoGetArgs, result *ConvoGetResult) error {
log.WithFields(log.Fields{"service": "convo", "rpc": "Get", "round": args.Round, "count": args.Count}).Debug()
round, err := srv.getRound(args.Round, convoRoundClosed)
if err != nil {
return err
}
nonce := BackwardNonce(args.Round)
outgoingOnionSize := srv.PKI.OutgoingOnionOverhead(srv.ServerName) + SizeEncryptedMessage
result.Onions = make([][]byte, args.Count)
for k := range result.Onions {
i := args.Offset + k
if v := round.incomingIndex[i]; v > -1 {
reply := round.replies[v]
onion := box.SealAfterPrecomputation(nil, reply, nonce, round.sharedKeys[i])
result.Onions[k] = onion
}
if len(result.Onions[k]) != outgoingOnionSize {
onion := make([]byte, outgoingOnionSize)
rand.Read(onion)
result.Onions[k] = onion
}
}
return nil
}
func FillWithFakeSingles(dest [][]byte, nonce *[24]byte, nextKeys []*[32]byte) {
ParallelFor(len(dest), func(p *P) {
for i, ok := p.Next(); ok; i, ok = p.Next() {
var exchange [SizeConvoExchange]byte
rand.Read(exchange[:])
onion, _ := onionbox.Seal(exchange[:], nonce, nextKeys)
dest[i] = onion
}
})
}
func laplace(mu, b float64) float64 {
var r [8]byte
if _, err := rand.Read(r[:]); err != nil {
panic(err)
}
x := binary.BigEndian.Uint64(r[:])
u := float64(x)/float64(^uint64(0)) - .5
var abs, sign float64
if u < 0 {
abs = -u
sign = -1
} else {
abs = u
sign = 1
}
return mu - b*sign*math.Log(1-2*abs)
}
func FillWithFakeIntroductions(dest [][]byte, noiseCounts []int, nonce *[24]byte, nextKeys []*[32]byte) {
buckets := make([]int, len(dest))
idx := 0
for b, count := range noiseCounts {
for i := 0; i < count; i++ {
buckets[idx] = b
idx++
}
}
ParallelFor(len(dest), func(p *P) {
for i, ok := p.Next(); ok; i, ok = p.Next() {
var exchange [SizeDialExchange]byte
binary.BigEndian.PutUint32(exchange[0:4], uint32(buckets[i]))
rand.Read(exchange[4:])
onion, _ := onionbox.Seal(exchange[:], nonce, nextKeys)
dest[i] = onion
}
})
}