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Diffstat (limited to 'whisper/whisperv2/envelope.go')
| -rw-r--r-- | whisper/whisperv2/envelope.go | 150 |
1 files changed, 0 insertions, 150 deletions
diff --git a/whisper/whisperv2/envelope.go b/whisper/whisperv2/envelope.go deleted file mode 100644 index 9f1c68204..000000000 --- a/whisper/whisperv2/envelope.go +++ /dev/null @@ -1,150 +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 Envelope element. For formal details please see -// the specs at https://github.com/ethereum/wiki/wiki/Whisper-PoC-1-Protocol-Spec#envelopes. - -package whisperv2 - -import ( - "crypto/ecdsa" - "encoding/binary" - "fmt" - "math/big" - "time" - - "github.com/ethereum/go-ethereum/common" - "github.com/ethereum/go-ethereum/common/math" - "github.com/ethereum/go-ethereum/crypto" - "github.com/ethereum/go-ethereum/crypto/ecies" - "github.com/ethereum/go-ethereum/rlp" -) - -// Envelope represents a clear-text data packet to transmit through the Whisper -// network. Its contents may or may not be encrypted and signed. -type Envelope struct { - Expiry uint32 // Whisper protocol specifies int32, really should be int64 - TTL uint32 // ^^^^^^ - Topics []Topic - Data []byte - Nonce uint32 - - hash common.Hash // Cached hash of the envelope to avoid rehashing every time -} - -// NewEnvelope wraps a Whisper message with expiration and destination data -// included into an envelope for network forwarding. -func NewEnvelope(ttl time.Duration, topics []Topic, msg *Message) *Envelope { - return &Envelope{ - Expiry: uint32(time.Now().Add(ttl).Unix()), - TTL: uint32(ttl.Seconds()), - Topics: topics, - Data: msg.bytes(), - Nonce: 0, - } -} - -// Seal closes the envelope by spending the requested amount of time as a proof -// of work on hashing the data. -func (self *Envelope) Seal(pow time.Duration) { - d := make([]byte, 64) - copy(d[:32], self.rlpWithoutNonce()) - - finish, bestBit := time.Now().Add(pow).UnixNano(), 0 - for nonce := uint32(0); time.Now().UnixNano() < finish; { - for i := 0; i < 1024; i++ { - binary.BigEndian.PutUint32(d[60:], nonce) - - d := new(big.Int).SetBytes(crypto.Keccak256(d)) - firstBit := math.FirstBitSet(d) - if firstBit > bestBit { - self.Nonce, bestBit = nonce, firstBit - } - nonce++ - } - } -} - -// rlpWithoutNonce returns the RLP encoded envelope contents, except the nonce. -func (self *Envelope) rlpWithoutNonce() []byte { - enc, _ := rlp.EncodeToBytes([]interface{}{self.Expiry, self.TTL, self.Topics, self.Data}) - return enc -} - -// Open extracts the message contained within a potentially encrypted envelope. -func (self *Envelope) Open(key *ecdsa.PrivateKey) (msg *Message, err error) { - // Split open the payload into a message construct - data := self.Data - - message := &Message{ - Flags: data[0], - Sent: time.Unix(int64(self.Expiry-self.TTL), 0), - TTL: time.Duration(self.TTL) * time.Second, - Hash: self.Hash(), - } - data = data[1:] - - if message.Flags&signatureFlag == signatureFlag { - if len(data) < signatureLength { - return nil, fmt.Errorf("unable to open envelope. First bit set but len(data) < len(signature)") - } - message.Signature, data = data[:signatureLength], data[signatureLength:] - } - message.Payload = data - - // Decrypt the message, if requested - if key == nil { - return message, nil - } - err = message.decrypt(key) - switch err { - case nil: - return message, nil - - case ecies.ErrInvalidPublicKey: // Payload isn't encrypted - return message, err - - default: - return nil, fmt.Errorf("unable to open envelope, decrypt failed: %v", err) - } -} - -// Hash returns the SHA3 hash of the envelope, calculating it if not yet done. -func (self *Envelope) Hash() common.Hash { - if (self.hash == common.Hash{}) { - enc, _ := rlp.EncodeToBytes(self) - self.hash = crypto.Keccak256Hash(enc) - } - return self.hash -} - -// DecodeRLP decodes an Envelope from an RLP data stream. -func (self *Envelope) DecodeRLP(s *rlp.Stream) error { - raw, err := s.Raw() - if err != nil { - return err - } - // The decoding of Envelope uses the struct fields but also needs - // to compute the hash of the whole RLP-encoded envelope. This - // type has the same structure as Envelope but is not an - // rlp.Decoder so we can reuse the Envelope struct definition. - type rlpenv Envelope - if err := rlp.DecodeBytes(raw, (*rlpenv)(self)); err != nil { - return err - } - self.hash = crypto.Keccak256Hash(raw) - return nil -} |