79aac01b02
The Bitcoin wire protocol includes several fields with their lengths encoded according to a variable length integer encoding scheme that does not enforce a unique encoding for all numbers. This can lead to a situation where deserializing and re-serializing the same data can result in different bytes. There are no currently known issues due to this, but it is safer to reject such subtle differences as they could potentially lead to exploits. Consequently, this commit modifies the varint decoding function to error when the value is not canonically encoded which effectively means that all messages with varints that are not canonically encoded will now be rejected. This will not cause issues with old client versions in regards to blocks and transactions since the data is deserialized into memory and then reserialized before being relayed thereby effectively erasing any non-canonical encodings. Also, new tests have been added to ensure non-canonical encodings are properly rejected and exercise the new code, and the default user agent version for wire has been bumped to version 0.2.1 to differentiate the new behavior. The equivalent logic was implemented in Bitcoin Core by PR 2884. |
||
---|---|---|
.. | ||
bench_test.go | ||
blockheader.go | ||
blockheader_test.go | ||
common.go | ||
common_test.go | ||
doc.go | ||
error.go | ||
fakeconn_test.go | ||
fakemessage_test.go | ||
fixedIO_test.go | ||
internal_test.go | ||
invvect.go | ||
invvect_test.go | ||
message.go | ||
message_test.go | ||
msgaddr.go | ||
msgaddr_test.go | ||
msgalert.go | ||
msgalert_test.go | ||
msgblock.go | ||
msgblock_test.go | ||
msgfilteradd.go | ||
msgfilteradd_test.go | ||
msgfilterclear.go | ||
msgfilterclear_test.go | ||
msgfilterload.go | ||
msgfilterload_test.go | ||
msggetaddr.go | ||
msggetaddr_test.go | ||
msggetblocks.go | ||
msggetblocks_test.go | ||
msggetdata.go | ||
msggetdata_test.go | ||
msggetheaders.go | ||
msggetheaders_test.go | ||
msgheaders.go | ||
msgheaders_test.go | ||
msginv.go | ||
msginv_test.go | ||
msgmempool.go | ||
msgmempool_test.go | ||
msgmerkleblock.go | ||
msgmerkleblock_test.go | ||
msgnotfound.go | ||
msgnotfound_test.go | ||
msgping.go | ||
msgping_test.go | ||
msgpong.go | ||
msgpong_test.go | ||
msgreject.go | ||
msgreject_test.go | ||
msgtx.go | ||
msgtx_test.go | ||
msgverack.go | ||
msgverack_test.go | ||
msgversion.go | ||
msgversion_test.go | ||
netaddress.go | ||
netaddress_test.go | ||
protocol.go | ||
protocol_test.go | ||
README.md | ||
shahash.go | ||
shahash_test.go |
wire
[] (https://travis-ci.org/btcsuite/btcd) ![ISC License] (http://img.shields.io/badge/license-ISC-blue.svg)
Package wire implements the bitcoin wire protocol. A comprehensive suite of tests with 100% test coverage is provided to ensure proper functionality.
There is an associated blog post about the release of this package here.
This package has intentionally been designed so it can be used as a standalone package for any projects needing to interface with bitcoin peers at the wire protocol level.
Documentation
[] (http://godoc.org/github.com/btcsuite/btcd/wire)
Full go doc
style documentation for the project can be viewed online without
installing this package by using the GoDoc site here:
http://godoc.org/github.com/btcsuite/btcd/wire
You can also view the documentation locally once the package is installed with
the godoc
tool by running godoc -http=":6060"
and pointing your browser to
http://localhost:6060/pkg/github.com/btcsuite/btcd/wire
Installation
$ go get github.com/btcsuite/btcd/wire
Bitcoin Message Overview
The bitcoin protocol consists of exchanging messages between peers. Each message is preceded by a header which identifies information about it such as which bitcoin network it is a part of, its type, how big it is, and a checksum to verify validity. All encoding and decoding of message headers is handled by this package.
To accomplish this, there is a generic interface for bitcoin messages named
Message
which allows messages of any type to be read, written, or passed
around through channels, functions, etc. In addition, concrete implementations
of most of the currently supported bitcoin messages are provided. For these
supported messages, all of the details of marshalling and unmarshalling to and
from the wire using bitcoin encoding are handled so the caller doesn't have to
concern themselves with the specifics.
Reading Messages Example
In order to unmarshal bitcoin messages from the wire, use the ReadMessage
function. It accepts any io.Reader
, but typically this will be a net.Conn
to a remote node running a bitcoin peer. Example syntax is:
// Use the most recent protocol version supported by the package and the
// main bitcoin network.
pver := wire.ProtocolVersion
btcnet := wire.MainNet
// Reads and validates the next bitcoin message from conn using the
// protocol version pver and the bitcoin network btcnet. The returns
// are a wire.Message, a []byte which contains the unmarshalled
// raw payload, and a possible error.
msg, rawPayload, err := wire.ReadMessage(conn, pver, btcnet)
if err != nil {
// Log and handle the error
}
See the package documentation for details on determining the message type.
Writing Messages Example
In order to marshal bitcoin messages to the wire, use the WriteMessage
function. It accepts any io.Writer
, but typically this will be a net.Conn
to a remote node running a bitcoin peer. Example syntax to request addresses
from a remote peer is:
// Use the most recent protocol version supported by the package and the
// main bitcoin network.
pver := wire.ProtocolVersion
btcnet := wire.MainNet
// Create a new getaddr bitcoin message.
msg := wire.NewMsgGetAddr()
// Writes a bitcoin message msg to conn using the protocol version
// pver, and the bitcoin network btcnet. The return is a possible
// error.
err := wire.WriteMessage(conn, msg, pver, btcnet)
if err != nil {
// Log and handle the error
}
GPG Verification Key
All official release tags are signed by Conformal so users can ensure the code has not been tampered with and is coming from the btcsuite developers. To verify the signature perform the following:
-
Download the public key from the Conformal website at https://opensource.conformal.com/GIT-GPG-KEY-conformal.txt
-
Import the public key into your GPG keyring:
gpg --import GIT-GPG-KEY-conformal.txt
-
Verify the release tag with the following command where
TAG_NAME
is a placeholder for the specific tag:git tag -v TAG_NAME
License
Package wire is licensed under the copyfree ISC License.