LBRYCommunity/lbrycrd
1
0
Fork 0
Code Issues 29 Pull requests 1 Projects Releases 32 Packages Wiki Activity
The blockchain that provides the digital content namespace for the LBRY protocol
9155 commits 22 branches 42 tags 99 MiB
C++ 66.5%
Python 15.1%
C 12.7%
M4 2.1%
Makefile 1.2%
Other 2.3%
Find a file
Gregory Maxwell b196b685c9 Test LowS in standardness, removes nuisance malleability vector. 
This adds SCRIPT_VERIFY_LOW_S to STANDARD_SCRIPT_VERIFY_FLAGS which
 will make the node require the canonical 'low-s' encoding for
 ECDSA signatures when relaying or mining.

Consensus behavior is unchanged.

The rational is explained in a81cd96805:
 Absent this kind of test ECDSA is not a strong signature as given
 a valid signature {r, s} both that value and {r, -s mod n} are valid.
 These two encodings have different hashes allowing third parties a
 vector to change users txids.  These attacks are avoided by picking
 a particular form as canonical and rejecting the other form(s); in
 the of the LOW_S rule, the smaller of the two possible S values is
 used.

If widely deployed this change would eliminate the last remaining
 known vector for nuisance malleability on boring SIGHASH_ALL
 p2pkh transactions.  On the down-side it will block most
 transactions made by sufficiently out of date software.

Unlike the other avenues to change txids on boring transactions this
 one was randomly violated by all deployed bitcoin software prior to
 its discovery.  So, while other malleability vectors where made
 non-standard as soon as they were discovered, this one has remained
 permitted.  Even BIP62 did not propose applying this rule to
 old version transactions, but conforming implementations have become
 much more common since BIP62 was initially written.

Bitcoin Core has produced compatible signatures since a28fb70e in
 September 2013, but this didn't make it into a release until 0.9
 in March 2014; Bitcoinj has done so for a similar span of time.
 Bitcoinjs and electrum have been more recently updated.

This does not replace the need for BIP62 or similar, as miners can
 still cooperate to break transactions.  Nor does it replace the
 need for wallet software to handle malleability sanely[1]. This
 only eliminates the cheap and irritating DOS attack.

[1] On the Malleability of Bitcoin Transactions
Marcin Andrychowicz, Stefan Dziembowski, Daniel Malinowski, Łukasz Mazurek
http://fc15.ifca.ai/preproceedings/bitcoin/paper_9.pdf
2015-10-06 03:50:38 +00:00
.tx Change transifex slug to translation-011x 2015-05-01 14:25:02 +02:00
build-aux/m4 build: make sure pkg-config checks are guarded by an m4_ifdef 2015-07-31 23:21:34 -04:00
contrib Fix debian/copyright list to be non-comma-separated. 2015-09-25 16:00:07 -07:00
depends Merge pull request #6619 2015-09-25 16:29:24 +02:00
doc doc: no longer require use of openssl in OpenBSD build guide 2015-10-01 14:55:57 +02:00
qa qa/pull-tester/rpc-tests.py: chmod 0755 2015-10-04 15:08:18 -04:00
share [trivial] Remove obsolete pixmaps 2015-09-13 17:57:25 +02:00
src Test LowS in standardness, removes nuisance malleability vector. 2015-10-06 03:50:38 +00:00
.gitattributes Separate protocol versioning from clientversion 2014-10-29 00:24:40 -04:00
.gitignore Add libbitcoinconsensus.pc to .gitignore 2014-12-20 21:26:31 +08:00
.travis.yml Migrated rpc-tests.sh to all python rpc-tests.py 2015-10-01 11:28:11 -07:00
autogen.sh Bugfix: Replace bashisms with standard sh to fix build on non-BASH systems 2014-10-03 23:45:26 +00:00
configure.ac Merge pull request #6744 2015-10-05 13:43:16 +02:00
CONTRIBUTING.md Add PR title prefix for trivial changes [skip ci] 2015-09-30 08:44:51 +02:00
COPYING Update contrib/debian/copyright 2015-09-15 16:38:08 +02:00
INSTALL Prettify some /Contrib READMEs 2013-10-21 20:07:31 -04:00
libbitcoinconsensus.pc.in libbitcoinconsensus: Add pkg-config support 2014-11-20 21:23:34 +00:00
Makefile.am Migrated rpc-tests.sh to all python rpc-tests.py 2015-10-01 11:28:11 -07:00
README.md Changed rpc-tests.sh to rpc-tests.py in README.md 2015-10-05 13:38:31 +02:00

README.md

Bitcoin Core integration/staging tree

Build Status

https://www.bitcoin.org

What is Bitcoin?

Bitcoin is an experimental new digital currency that enables instant payments to anyone, anywhere in the world. Bitcoin uses peer-to-peer technology to operate with no central authority: managing transactions and issuing money are carried out collectively by the network. Bitcoin Core is the name of open source software which enables the use of this currency.

For more information, as well as an immediately useable, binary version of the Bitcoin Core software, see https://www.bitcoin.org/en/download.

License

Bitcoin Core is released under the terms of the MIT license. See COPYING for more information or see http://opensource.org/licenses/MIT.

Development Process

The master branch is regularly built and tested, but is not guaranteed to be completely stable. Tags are created regularly to indicate new official, stable release versions of Bitcoin.

The contribution workflow is described in CONTRIBUTING.md.

The developer mailing list should be used to discuss complicated or controversial changes before working on a patch set.

Developer IRC can be found on Freenode at #bitcoin-core-dev.

Testing

Testing and code review is the bottleneck for development; we get more pull requests than we can review and test on short notice. Please be patient and help out by testing other people's pull requests, and remember this is a security-critical project where any mistake might cost people lots of money.

Automated Testing

Developers are strongly encouraged to write unit tests for new code, and to submit new unit tests for old code. Unit tests can be compiled and run (assuming they weren't disabled in configure) with: make check

There are also regression and integration tests of the RPC interface, written in Python, that are run automatically on the build server. These tests can be run with: qa/pull-tester/rpc-tests.py

Every pull request is built for both Windows and Linux on a dedicated server, and unit and sanity tests are automatically run. The binaries produced may be used for manual QA testing — a link to them will appear in a comment on the pull request posted by BitcoinPullTester. See https://github.com/TheBlueMatt/test-scripts for the build/test scripts.

Manual Quality Assurance (QA) Testing

Large changes should have a test plan, and should be tested by somebody other than the developer who wrote the code. See https://github.com/bitcoin/QA/ for how to create a test plan.

Translations

Changes to translations as well as new translations can be submitted to Bitcoin Core's Transifex page.

Translations are periodically pulled from Transifex and merged into the git repository. See the translation process for details on how this works.

Important: We do not accept translation changes as GitHub pull requests because the next pull from Transifex would automatically overwrite them again.

Translators should also subscribe to the mailing list.