lbcd/blockchain
Olaoluwa Osuntokun d0768abcc4 BIP0141+blockchain: implement segwit block validation rules
This commit implements the new block validation rules as defined by
BIP0141. The new rules include the constraints that if a block has
transactions with witness data, then there MUST be a commitment within
the conies transaction to the root of a new merkle tree which commits
to the wtxid of all transactions. Additionally, rather than limiting
the size of a block by size in bytes, blocks are now limited by their
total weight unit. Similarly, a newly define “sig op cost” is now used
to limit the signature validation cost of transactions found within
blocks.
2017-08-13 23:17:40 -05:00
..
fullblocktests BIP0141+blockchain: implement segwit block validation rules 2017-08-13 23:17:40 -05:00
indexers multi: Update markdown files for GFM changes. 2017-05-25 12:06:16 -05:00
testdata blockchain: Rework to use new db interface. 2016-04-11 16:47:27 -05:00
accept.go blockchain: Refactor main block index logic. 2017-02-01 13:14:41 -06:00
bench_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
blockindex.go blockchain: Use hash values in structs. 2017-02-03 11:36:33 -06:00
blocklocator.go blockchain: Use hash values in structs. 2017-02-03 11:36:33 -06:00
chain.go BIP0141+blockchain: implement segwit block validation rules 2017-08-13 23:17:40 -05:00
chain_test.go rpctest: Make subpackage of integration. 2017-05-11 15:17:29 -05:00
chainio.go BIP0141+blockchain: implement segwit block validation rules 2017-08-13 23:17:40 -05:00
chainio_test.go blockchain: Correct invalid assertion. 2017-07-01 02:25:41 -05:00
checkpoints.go multi: Improvements to configurable checkpoints. 2017-01-23 12:07:54 -06:00
common_test.go blockchain: Allow adding additional checkpoints 2017-01-18 23:56:43 +01:00
compress.go blockchain: Rework to use new db interface. 2016-04-11 16:47:27 -05:00
compress_test.go blockchain: Rework to use new db interface. 2016-04-11 16:47:27 -05:00
difficulty.go blockchain: Refactor main block index logic. 2017-02-01 13:14:41 -06:00
difficulty_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
doc.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
error.go BIP0141+blockchain: implement segwit block validation rules 2017-08-13 23:17:40 -05:00
error_test.go Implement infrastructure for BIP0009. 2016-11-30 13:51:59 -06:00
example_test.go blockchain: Expose main chain flag on ProcessBlock. 2016-10-13 16:47:50 -05:00
fullblocks_test.go BIP0141+blockchain: implement segwit block validation rules 2017-08-13 23:17:40 -05:00
internal_test.go blockchain: Use int64 timestamps in block nodes. 2017-01-31 17:51:29 -06:00
log.go all: Remove seelog logger. 2017-06-19 16:46:50 -04:00
mediantime.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
mediantime_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
merkle.go BIP0141+blockchain: add functions for extracting and validating witness commitment 2017-08-13 23:17:40 -05:00
merkle_test.go BIP0141+blockchain: add functions for extracting and validating witness commitment 2017-08-13 23:17:40 -05:00
notifications.go blockchain: Rework to use new db interface. 2016-04-11 16:47:27 -05:00
process.go blockchain: Ignore side chains in exists check. 2017-02-03 11:02:35 -06:00
README.md multi: Update markdown files for GFM changes. 2017-05-25 12:06:16 -05:00
reorganization_test.go multi: Simplify code per gosimple linter. 2017-07-01 02:25:10 -05:00
scriptval.go BIP0141+blockchain: implement segwit block validation rules 2017-08-13 23:17:40 -05:00
scriptval_test.go BIP0141+blockchain: implement segwit block validation rules 2017-08-13 23:17:40 -05:00
thresholdstate.go BIP0144: properly fetch witness data from witness-enabled peers 2017-08-13 23:17:40 -05:00
thresholdstate_test.go blockchain: Use hash values in structs. 2017-02-03 11:36:33 -06:00
timesorter.go blockchain: Use int64 timestamps in block nodes. 2017-01-31 17:51:29 -06:00
timesorter_test.go blockchain: Use int64 timestamps in block nodes. 2017-01-31 17:51:29 -06:00
utxoviewpoint.go multi: Simplify code per gosimple linter. 2017-07-01 02:25:10 -05:00
validate.go BIP0141+blockchain: implement segwit block validation rules 2017-08-13 23:17:40 -05:00
validate_test.go BIP0141+blockchain: implement segwit block validation rules 2017-08-13 23:17:40 -05:00
versionbits.go Fix the unknown new rules activation warning 2017-08-09 19:10:28 -04:00
weight.go BIP0141+blockchain: implement tx/block weight calculation funcitons 2017-08-13 23:17:40 -05:00

blockchain

Build Status ISC License GoDoc

Package blockchain implements bitcoin block handling and chain selection rules. The test coverage is currently only around 60%, but will be increasing over time. See test_coverage.txt for the gocov coverage report. Alternatively, if you are running a POSIX OS, you can run the cov_report.sh script for a real-time report. Package blockchain is licensed under the liberal ISC license.

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 handle processing of blocks into the bitcoin block chain.

Installation and Updating

$ go get -u github.com/btcsuite/btcd/blockchain

Bitcoin Chain Processing Overview

Before a block is allowed into the block chain, it must go through an intensive series of validation rules. The following list serves as a general outline of those rules to provide some intuition into what is going on under the hood, but is by no means exhaustive:

  • Reject duplicate blocks
  • Perform a series of sanity checks on the block and its transactions such as verifying proof of work, timestamps, number and character of transactions, transaction amounts, script complexity, and merkle root calculations
  • Compare the block against predetermined checkpoints for expected timestamps and difficulty based on elapsed time since the checkpoint
  • Save the most recent orphan blocks for a limited time in case their parent blocks become available
  • Stop processing if the block is an orphan as the rest of the processing depends on the block's position within the block chain
  • Perform a series of more thorough checks that depend on the block's position within the block chain such as verifying block difficulties adhere to difficulty retarget rules, timestamps are after the median of the last several blocks, all transactions are finalized, checkpoint blocks match, and block versions are in line with the previous blocks
  • Determine how the block fits into the chain and perform different actions accordingly in order to ensure any side chains which have higher difficulty than the main chain become the new main chain
  • When a block is being connected to the main chain (either through reorganization of a side chain to the main chain or just extending the main chain), perform further checks on the block's transactions such as verifying transaction duplicates, script complexity for the combination of connected scripts, coinbase maturity, double spends, and connected transaction values
  • Run the transaction scripts to verify the spender is allowed to spend the coins
  • Insert the block into the block database

Examples

  • ProcessBlock Example
    Demonstrates how to create a new chain instance and use ProcessBlock to attempt to attempt add a block to the chain. This example intentionally attempts to insert a duplicate genesis block to illustrate how an invalid block is handled.

  • CompactToBig Example
    Demonstrates how to convert the compact "bits" in a block header which represent the target difficulty to a big integer and display it using the typical hex notation.

  • BigToCompact Example
    Demonstrates how to convert how to convert a target difficulty into the compact "bits" in a block header which represent that target difficulty.

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 blockchain is licensed under the copyfree ISC License.