This is to mitigate CVE-2017-12842. Along the way, also error when
deserializing transactions that have the witness marker flag set
but have no witnesses. This matches Bitcoin Core's behaviour initially
introduced here https://github.com/bitcoin/bitcoin/pull/14039. Allowing
such transactions is benign, but this makes sure that our parsing code
matches Core's exactly.
Summary of changes:
- Add a new const TxFlagMarker to indicate the flag prefix byte.
- Add a new TxFlag type to enumerate the flags supported by the
tx parser.
This allows us to avoid hardcoded magics, and will make it easier
to support new flags in future.
- Improve code comments.
Closes#1598.
This commit implements the new witness encoding/decoding for
transactions as specified by BIP0144. After segwit activation, a
special transaction encoding is used to signal to upgraded nodes that
the transaction being deserialized bares witness data. The prior
BtcEncode and BtcDecode methods have been extended to be aware of the
new signaling bytes and the encoding of witness data within
transactions.
Additionally, a new method has been added to calculate the “stripped
size” of a transaction/block which is defined as the size of a
transaction/block *excluding* any witness data.
This commit modifies the existing wire.Message interface to introduce a
new MessageEncoding variant which dictates the exact encoding to be
used when serializing and deserializing messages. Such an option is now
necessary due to the segwit soft-fork package, as btcd will need to be
able to optionally encode transactions/blocks without witness data to
un-upgraded peers.
Two new functions have been introduced: ReadMessageWithEncodingN and
WriteMessageWithEncodingN which wrap BtcDecode/BtcEncode with the
desired encoding format.
This modifies the NewMsgTx function to accept the transaction version as
a parameter and updates all callers.
The reason for this change is so the transaction version can be bumped
in wire without breaking existing tests and to provide the caller with
the flexibility to create the specific transaction version they desire.
This is mostly a backport of some of the same modifications made in
Decred along with a few additional things cleaned up. In particular,
this updates the code to make use of the new chainhash package.
Also, since this required API changes anyways and the hash algorithm is
no longer tied specifically to SHA, all other functions throughout the
code base which had "Sha" in their name have been changed to Hash so
they are not incorrectly implying the hash algorithm.
The following is an overview of the changes:
- Remove the wire.ShaHash type
- Update all references to wire.ShaHash to the new chainhash.Hash type
- Rename the following functions and update all references:
- wire.BlockHeader.BlockSha -> BlockHash
- wire.MsgBlock.BlockSha -> BlockHash
- wire.MsgBlock.TxShas -> TxHashes
- wire.MsgTx.TxSha -> TxHash
- blockchain.ShaHashToBig -> HashToBig
- peer.ShaFunc -> peer.HashFunc
- Rename all variables that included sha in their name to include hash
instead
- Update for function name changes in other dependent packages such as
btcutil
- Update copyright dates on all modified files
- Update glide.lock file to use the required version of btcutil
Putting the test code in the same package makes it easier for forks
since they don't have to change the import paths as much and it also
gets rid of the need for internal_test.go to bridge.
This same thing should probably be done for the majority of the code
base.
This commit updates the wire tests for transactions which force
serialization and deserialization errors to force an error in the the
transaction lock time path.
This brings the wire test coverage back up to 100%.
This commit removes the error returns from the BlockHeader.BlockSha,
MsgBlock.BlockSha, and MsgTx.TxSha functions since they can never fail and
end up causing a lot of unneeded error checking throughout the code base.
It also updates all call sites for the change.
This commit provides a new function named PkScriptLocs on the MsgTx type
which can be used to efficiently retrieve a list of offsets for the public
key scripts for the serialized form of the transaction.
This is useful for certain applications which store fully serialized
transactions and want to be able to quickly index into the serialized
transaction to extract a give public key script directly thereby avoiding
the need to deserialize the entire transaction.
This commit contains the entire btcwire repository along with several
changes needed to move all of the files into the wire directory in
order to prepare it for merging. This does NOT update btcd or any of the
other packages to use the new location as that will be done separately.
- All import paths in the old btcwire test files have been changed to the
new location
- All references to btcwire as the package name have been chagned to
wire
- The coveralls badge has been removed since it unfortunately doesn't
support coverage of sub-packages
This is ongoing work toward #214.
