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Diffstat (limited to 'whisper/whisperv2/message.go')
| -rw-r--r-- | whisper/whisperv2/message.go | 158 |
1 files changed, 0 insertions, 158 deletions
diff --git a/whisper/whisperv2/message.go b/whisper/whisperv2/message.go deleted file mode 100644 index 66648c3be..000000000 --- a/whisper/whisperv2/message.go +++ /dev/null @@ -1,158 +0,0 @@ -// Copyright 2014 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/>. - -// Contains the Whisper protocol Message element. For formal details please see -// the specs at https://github.com/ethereum/wiki/wiki/Whisper-PoC-1-Protocol-Spec#messages. - -package whisperv2 - -import ( - "crypto/ecdsa" - crand "crypto/rand" - "fmt" - "math/rand" - "time" - - "github.com/ethereum/go-ethereum/common" - "github.com/ethereum/go-ethereum/crypto" - "github.com/ethereum/go-ethereum/crypto/ecies" - "github.com/ethereum/go-ethereum/log" -) - -// Message represents an end-user data packet to transmit through the Whisper -// protocol. These are wrapped into Envelopes that need not be understood by -// intermediate nodes, just forwarded. -type Message struct { - Flags byte // First bit is signature presence, rest reserved and should be random - Signature []byte - Payload []byte - - Sent time.Time // Time when the message was posted into the network - TTL time.Duration // Maximum time to live allowed for the message - - To *ecdsa.PublicKey // Message recipient (identity used to decode the message) - Hash common.Hash // Message envelope hash to act as a unique id -} - -// Options specifies the exact way a message should be wrapped into an Envelope. -type Options struct { - From *ecdsa.PrivateKey - To *ecdsa.PublicKey - TTL time.Duration - Topics []Topic -} - -// NewMessage creates and initializes a non-signed, non-encrypted Whisper message. -func NewMessage(payload []byte) *Message { - // Construct an initial flag set: no signature, rest random - flags := byte(rand.Intn(256)) - flags &= ^signatureFlag - - // Assemble and return the message - return &Message{ - Flags: flags, - Payload: payload, - Sent: time.Now(), - } -} - -// Wrap bundles the message into an Envelope to transmit over the network. -// -// pow (Proof Of Work) controls how much time to spend on hashing the message, -// inherently controlling its priority through the network (smaller hash, bigger -// priority). -// -// The user can control the amount of identity, privacy and encryption through -// the options parameter as follows: -// - options.From == nil && options.To == nil: anonymous broadcast -// - options.From != nil && options.To == nil: signed broadcast (known sender) -// - options.From == nil && options.To != nil: encrypted anonymous message -// - options.From != nil && options.To != nil: encrypted signed message -func (self *Message) Wrap(pow time.Duration, options Options) (*Envelope, error) { - // Use the default TTL if non was specified - if options.TTL == 0 { - options.TTL = DefaultTTL - } - self.TTL = options.TTL - - // Sign and encrypt the message if requested - if options.From != nil { - if err := self.sign(options.From); err != nil { - return nil, err - } - } - if options.To != nil { - if err := self.encrypt(options.To); err != nil { - return nil, err - } - } - // Wrap the processed message, seal it and return - envelope := NewEnvelope(options.TTL, options.Topics, self) - envelope.Seal(pow) - - return envelope, nil -} - -// sign calculates and sets the cryptographic signature for the message , also -// setting the sign flag. -func (self *Message) sign(key *ecdsa.PrivateKey) (err error) { - self.Flags |= signatureFlag - self.Signature, err = crypto.Sign(self.hash(), key) - return -} - -// Recover retrieves the public key of the message signer. -func (self *Message) Recover() *ecdsa.PublicKey { - defer func() { recover() }() // in case of invalid signature - - // Short circuit if no signature is present - if self.Signature == nil { - return nil - } - // Otherwise try and recover the signature - pub, err := crypto.SigToPub(self.hash(), self.Signature) - if err != nil { - log.Error(fmt.Sprintf("Could not get public key from signature: %v", err)) - return nil - } - return pub -} - -// encrypt encrypts a message payload with a public key. -func (self *Message) encrypt(key *ecdsa.PublicKey) (err error) { - self.Payload, err = ecies.Encrypt(crand.Reader, ecies.ImportECDSAPublic(key), self.Payload, nil, nil) - return -} - -// decrypt decrypts an encrypted payload with a private key. -func (self *Message) decrypt(key *ecdsa.PrivateKey) error { - cleartext, err := ecies.ImportECDSA(key).Decrypt(crand.Reader, self.Payload, nil, nil) - if err == nil { - self.Payload = cleartext - } - return err -} - -// hash calculates the SHA3 checksum of the message flags and payload. -func (self *Message) hash() []byte { - return crypto.Keccak256(append([]byte{self.Flags}, self.Payload...)) -} - -// bytes flattens the message contents (flags, signature and payload) into a -// single binary blob. -func (self *Message) bytes() []byte { - return append([]byte{self.Flags}, append(self.Signature, self.Payload...)...) -} |