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-rw-r--r--whisper/whisperv5/message.go352
1 files changed, 0 insertions, 352 deletions
diff --git a/whisper/whisperv5/message.go b/whisper/whisperv5/message.go
deleted file mode 100644
index 35711d724..000000000
--- a/whisper/whisperv5/message.go
+++ /dev/null
@@ -1,352 +0,0 @@
-// 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/>.
-
-// Contains the Whisper protocol Message element.
-
-package whisperv5
-
-import (
- "crypto/aes"
- "crypto/cipher"
- "crypto/ecdsa"
- crand "crypto/rand"
- "encoding/binary"
- "errors"
- "strconv"
-
- "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"
-)
-
-// MessageParams specifies the exact way a message should be wrapped into an Envelope.
-type MessageParams struct {
- TTL uint32
- Src *ecdsa.PrivateKey
- Dst *ecdsa.PublicKey
- KeySym []byte
- Topic TopicType
- WorkTime uint32
- PoW float64
- Payload []byte
- Padding []byte
-}
-
-// SentMessage 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 sentMessage struct {
- Raw []byte
-}
-
-// ReceivedMessage represents a data packet to be received through the
-// Whisper protocol.
-type ReceivedMessage struct {
- Raw []byte
-
- Payload []byte
- Padding []byte
- Signature []byte
-
- PoW float64 // Proof of work as described in the Whisper spec
- Sent uint32 // Time when the message was posted into the network
- TTL uint32 // Maximum time to live allowed for the message
- Src *ecdsa.PublicKey // Message recipient (identity used to decode the message)
- Dst *ecdsa.PublicKey // Message recipient (identity used to decode the message)
- Topic TopicType
-
- SymKeyHash common.Hash // The Keccak256Hash of the key, associated with the Topic
- EnvelopeHash common.Hash // Message envelope hash to act as a unique id
- EnvelopeVersion uint64
-}
-
-func isMessageSigned(flags byte) bool {
- return (flags & signatureFlag) != 0
-}
-
-func (msg *ReceivedMessage) isSymmetricEncryption() bool {
- return msg.SymKeyHash != common.Hash{}
-}
-
-func (msg *ReceivedMessage) isAsymmetricEncryption() bool {
- return msg.Dst != nil
-}
-
-// NewSentMessage creates and initializes a non-signed, non-encrypted Whisper message.
-func NewSentMessage(params *MessageParams) (*sentMessage, error) {
- msg := sentMessage{}
- msg.Raw = make([]byte, 1, len(params.Payload)+len(params.Padding)+signatureLength+padSizeLimit)
- msg.Raw[0] = 0 // set all the flags to zero
- err := msg.appendPadding(params)
- if err != nil {
- return nil, err
- }
- msg.Raw = append(msg.Raw, params.Payload...)
- return &msg, nil
-}
-
-// getSizeOfLength returns the number of bytes necessary to encode the entire size padding (including these bytes)
-func getSizeOfLength(b []byte) (sz int, err error) {
- sz = intSize(len(b)) // first iteration
- sz = intSize(len(b) + sz) // second iteration
- if sz > 3 {
- err = errors.New("oversized padding parameter")
- }
- return sz, err
-}
-
-// sizeOfIntSize returns minimal number of bytes necessary to encode an integer value
-func intSize(i int) (s int) {
- for s = 1; i >= 256; s++ {
- i /= 256
- }
- return s
-}
-
-// appendPadding appends the pseudorandom padding bytes and sets the padding flag.
-// The last byte contains the size of padding (thus, its size must not exceed 256).
-func (msg *sentMessage) appendPadding(params *MessageParams) error {
- rawSize := len(params.Payload) + 1
- if params.Src != nil {
- rawSize += signatureLength
- }
- odd := rawSize % padSizeLimit
-
- if len(params.Padding) != 0 {
- padSize := len(params.Padding)
- padLengthSize, err := getSizeOfLength(params.Padding)
- if err != nil {
- return err
- }
- totalPadSize := padSize + padLengthSize
- buf := make([]byte, 8)
- binary.LittleEndian.PutUint32(buf, uint32(totalPadSize))
- buf = buf[:padLengthSize]
- msg.Raw = append(msg.Raw, buf...)
- msg.Raw = append(msg.Raw, params.Padding...)
- msg.Raw[0] |= byte(padLengthSize) // number of bytes indicating the padding size
- } else if odd != 0 {
- totalPadSize := padSizeLimit - odd
- if totalPadSize > 255 {
- // this algorithm is only valid if padSizeLimit < 256.
- // if padSizeLimit will ever change, please fix the algorithm
- // (please see also ReceivedMessage.extractPadding() function).
- panic("please fix the padding algorithm before releasing new version")
- }
- buf := make([]byte, totalPadSize)
- _, err := crand.Read(buf[1:])
- if err != nil {
- return err
- }
- if totalPadSize > 6 && !validateSymmetricKey(buf) {
- return errors.New("failed to generate random padding of size " + strconv.Itoa(totalPadSize))
- }
- buf[0] = byte(totalPadSize)
- msg.Raw = append(msg.Raw, buf...)
- msg.Raw[0] |= byte(0x1) // number of bytes indicating the padding size
- }
- return nil
-}
-
-// sign calculates and sets the cryptographic signature for the message,
-// also setting the sign flag.
-func (msg *sentMessage) sign(key *ecdsa.PrivateKey) error {
- if isMessageSigned(msg.Raw[0]) {
- // this should not happen, but no reason to panic
- log.Error("failed to sign the message: already signed")
- return nil
- }
-
- msg.Raw[0] |= signatureFlag
- hash := crypto.Keccak256(msg.Raw)
- signature, err := crypto.Sign(hash, key)
- if err != nil {
- msg.Raw[0] &= ^signatureFlag // clear the flag
- return err
- }
- msg.Raw = append(msg.Raw, signature...)
- return nil
-}
-
-// encryptAsymmetric encrypts a message with a public key.
-func (msg *sentMessage) encryptAsymmetric(key *ecdsa.PublicKey) error {
- if !ValidatePublicKey(key) {
- return errors.New("invalid public key provided for asymmetric encryption")
- }
- encrypted, err := ecies.Encrypt(crand.Reader, ecies.ImportECDSAPublic(key), msg.Raw, nil, nil)
- if err == nil {
- msg.Raw = encrypted
- }
- return err
-}
-
-// encryptSymmetric encrypts a message with a topic key, using AES-GCM-256.
-// nonce size should be 12 bytes (see cipher.gcmStandardNonceSize).
-func (msg *sentMessage) encryptSymmetric(key []byte) (nonce []byte, err error) {
- if !validateSymmetricKey(key) {
- return nil, errors.New("invalid key provided for symmetric encryption")
- }
-
- block, err := aes.NewCipher(key)
- if err != nil {
- return nil, err
- }
- aesgcm, err := cipher.NewGCM(block)
- if err != nil {
- return nil, err
- }
-
- // never use more than 2^32 random nonces with a given key
- nonce = make([]byte, aesgcm.NonceSize())
- _, err = crand.Read(nonce)
- if err != nil {
- return nil, err
- } else if !validateSymmetricKey(nonce) {
- return nil, errors.New("crypto/rand failed to generate nonce")
- }
-
- msg.Raw = aesgcm.Seal(nil, nonce, msg.Raw, nil)
- return nonce, nil
-}
-
-// Wrap bundles the message into an Envelope to transmit over the network.
-func (msg *sentMessage) Wrap(options *MessageParams) (envelope *Envelope, err error) {
- if options.TTL == 0 {
- options.TTL = DefaultTTL
- }
- if options.Src != nil {
- if err = msg.sign(options.Src); err != nil {
- return nil, err
- }
- }
- var nonce []byte
- if options.Dst != nil {
- err = msg.encryptAsymmetric(options.Dst)
- } else if options.KeySym != nil {
- nonce, err = msg.encryptSymmetric(options.KeySym)
- } else {
- err = errors.New("unable to encrypt the message: neither symmetric nor assymmetric key provided")
- }
- if err != nil {
- return nil, err
- }
-
- envelope = NewEnvelope(options.TTL, options.Topic, nonce, msg)
- if err = envelope.Seal(options); err != nil {
- return nil, err
- }
- return envelope, nil
-}
-
-// decryptSymmetric decrypts a message with a topic key, using AES-GCM-256.
-// nonce size should be 12 bytes (see cipher.gcmStandardNonceSize).
-func (msg *ReceivedMessage) decryptSymmetric(key []byte, nonce []byte) error {
- block, err := aes.NewCipher(key)
- if err != nil {
- return err
- }
- aesgcm, err := cipher.NewGCM(block)
- if err != nil {
- return err
- }
- if len(nonce) != aesgcm.NonceSize() {
- log.Error("decrypting the message", "AES nonce size", len(nonce))
- return errors.New("wrong AES nonce size")
- }
- decrypted, err := aesgcm.Open(nil, nonce, msg.Raw, nil)
- if err != nil {
- return err
- }
- msg.Raw = decrypted
- return nil
-}
-
-// decryptAsymmetric decrypts an encrypted payload with a private key.
-func (msg *ReceivedMessage) decryptAsymmetric(key *ecdsa.PrivateKey) error {
- decrypted, err := ecies.ImportECDSA(key).Decrypt(msg.Raw, nil, nil)
- if err == nil {
- msg.Raw = decrypted
- }
- return err
-}
-
-// Validate checks the validity and extracts the fields in case of success
-func (msg *ReceivedMessage) Validate() bool {
- end := len(msg.Raw)
- if end < 1 {
- return false
- }
-
- if isMessageSigned(msg.Raw[0]) {
- end -= signatureLength
- if end <= 1 {
- return false
- }
- msg.Signature = msg.Raw[end:]
- msg.Src = msg.SigToPubKey()
- if msg.Src == nil {
- return false
- }
- }
-
- padSize, ok := msg.extractPadding(end)
- if !ok {
- return false
- }
-
- msg.Payload = msg.Raw[1+padSize : end]
- return true
-}
-
-// extractPadding extracts the padding from raw message.
-// although we don't support sending messages with padding size
-// exceeding 255 bytes, such messages are perfectly valid, and
-// can be successfully decrypted.
-func (msg *ReceivedMessage) extractPadding(end int) (int, bool) {
- paddingSize := 0
- sz := int(msg.Raw[0] & paddingMask) // number of bytes indicating the entire size of padding (including these bytes)
- // could be zero -- it means no padding
- if sz != 0 {
- paddingSize = int(bytesToUintLittleEndian(msg.Raw[1 : 1+sz]))
- if paddingSize < sz || paddingSize+1 > end {
- return 0, false
- }
- msg.Padding = msg.Raw[1+sz : 1+paddingSize]
- }
- return paddingSize, true
-}
-
-// SigToPubKey retrieves the public key of the message signer.
-func (msg *ReceivedMessage) SigToPubKey() *ecdsa.PublicKey {
- defer func() { recover() }() // in case of invalid signature
-
- pub, err := crypto.SigToPub(msg.hash(), msg.Signature)
- if err != nil {
- log.Error("failed to recover public key from signature", "err", err)
- return nil
- }
- return pub
-}
-
-// hash calculates the SHA3 checksum of the message flags, payload and padding.
-func (msg *ReceivedMessage) hash() []byte {
- if isMessageSigned(msg.Raw[0]) {
- sz := len(msg.Raw) - signatureLength
- return crypto.Keccak256(msg.Raw[:sz])
- }
- return crypto.Keccak256(msg.Raw)
-}