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 exports the ReadVarString and WriteVarString functions so
they are available for callers to use.
A variable length string is encoded as a variable length integer
containing the length of the string followed by the bytes that represent
the string itself.
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.
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.
