89 lines
3.0 KiB
Go
89 lines
3.0 KiB
Go
// Copyright 2016 The go-ethereum Authors
|
|
// This file is part of the go-ethereum library.
|
|
//
|
|
// The go-ethereum library is free software: you can redistribute it and/or modify
|
|
// it under the terms of the GNU Lesser General Public License as published by
|
|
// the Free Software Foundation, either version 3 of the License, or
|
|
// (at your option) any later version.
|
|
//
|
|
// The go-ethereum library is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU Lesser General Public License for more details.
|
|
//
|
|
// You should have received a copy of the GNU Lesser General Public License
|
|
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
/*
|
|
Package whisper implements the Whisper PoC-1.
|
|
|
|
(https://github.com/ethereum/wiki/wiki/Whisper-PoC-1-Protocol-Spec)
|
|
|
|
Whisper combines aspects of both DHTs and datagram messaging systems (e.g. UDP).
|
|
As such it may be likened and compared to both, not dissimilar to the
|
|
matter/energy duality (apologies to physicists for the blatant abuse of a
|
|
fundamental and beautiful natural principle).
|
|
|
|
Whisper is a pure identity-based messaging system. Whisper provides a low-level
|
|
(non-application-specific) but easily-accessible API without being based upon
|
|
or prejudiced by the low-level hardware attributes and characteristics,
|
|
particularly the notion of singular endpoints.
|
|
*/
|
|
package whisperv5
|
|
|
|
import (
|
|
"fmt"
|
|
"time"
|
|
)
|
|
|
|
const (
|
|
EnvelopeVersion = uint64(0)
|
|
ProtocolVersion = uint64(5)
|
|
ProtocolVersionStr = "5.0"
|
|
ProtocolName = "shh"
|
|
|
|
statusCode = 0
|
|
messagesCode = 1
|
|
p2pCode = 2
|
|
mailRequestCode = 3
|
|
NumberOfMessageCodes = 32
|
|
|
|
paddingMask = byte(3)
|
|
signatureFlag = byte(4)
|
|
|
|
TopicLength = 4
|
|
signatureLength = 65
|
|
aesKeyLength = 32
|
|
saltLength = 12
|
|
AESNonceMaxLength = 12
|
|
|
|
MaxMessageLength = 0xFFFF // todo: remove this restriction after testing in morden and analizing stats. this should be regulated by MinimumPoW.
|
|
MinimumPoW = 10.0 // todo: review
|
|
|
|
padSizeLimitLower = 128 // it can not be less - we don't want to reveal the absence of signature
|
|
padSizeLimitUpper = 256 // just an arbitrary number, could be changed without losing compatibility
|
|
|
|
expirationCycle = time.Second
|
|
transmissionCycle = 300 * time.Millisecond
|
|
|
|
DefaultTTL = 50 // seconds
|
|
SynchAllowance = 10 // seconds
|
|
)
|
|
|
|
type unknownVersionError uint64
|
|
|
|
func (e unknownVersionError) Error() string {
|
|
return fmt.Sprintf("invalid envelope version %d", uint64(e))
|
|
}
|
|
|
|
// MailServer represents a mail server, capable of
|
|
// archiving the old messages for subsequent delivery
|
|
// to the peers. Any implementation must ensure that both
|
|
// functions are thread-safe. Also, they must return ASAP.
|
|
// DeliverMail should use directMessagesCode for delivery,
|
|
// in order to bypass the expiry checks.
|
|
type MailServer interface {
|
|
Archive(env *Envelope)
|
|
DeliverMail(whisperPeer *Peer, data []byte)
|
|
}
|