lbcd/txscript
Olaoluwa Osuntokun 0029905d43 Integrate a valid ECDSA signature cache into btcd
Introduce an ECDSA signature verification into btcd in order to
mitigate a certain DoS attack and as a performance optimization.

The benefits of SigCache are two fold. Firstly, usage of SigCache
mitigates a DoS attack wherein an attacker causes a victim's client to
hang due to worst-case behavior triggered while processing attacker
crafted invalid transactions. A detailed description of the mitigated
DoS attack can be found here: https://bitslog.wordpress.com/2013/01/23/fixed-bitcoin-vulnerability-explanation-why-the-signature-cache-is-a-dos-protection/
Secondly, usage of the SigCache introduces a signature verification
optimization which speeds up the validation of transactions within a
block, if they've already been seen and verified within the mempool.

The server itself manages the sigCache instance. The blockManager and
txMempool respectively now receive pointers to the created sigCache
instance. All read (sig triplet existence) operations on the sigCache
will not block unless a separate goroutine is adding an entry (writing)
to the sigCache. GetBlockTemplate generation now also utilizes the
sigCache in order to avoid unnecessarily double checking signatures
when generating a template after previously accepting a txn to the
mempool. Consequently, the CPU miner now also employs the same
optimization.

The maximum number of entries for the sigCache has been introduced as a
config parameter in order to allow users to configure the amount of
memory consumed by this new additional caching.
2015-10-08 17:31:42 -07:00
..
data txscript: Consensus audit. 2015-05-06 09:41:50 -05:00
consensus.go Revert "Move IsFinalizedTransaction to txscript." 2015-06-29 11:12:35 -04:00
doc.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
engine.go Integrate a valid ECDSA signature cache into btcd 2015-10-08 17:31:42 -07:00
engine_test.go Integrate a valid ECDSA signature cache into btcd 2015-10-08 17:31:42 -07:00
error.go txscript: Make error strings idiomatic. 2015-08-09 14:06:36 +01:00
example_test.go Integrate a valid ECDSA signature cache into btcd 2015-10-08 17:31:42 -07:00
internal_test.go txscript: Test consistency and cleanup. 2015-05-04 16:04:29 -05:00
log.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
log_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
opcode.go Integrate a valid ECDSA signature cache into btcd 2015-10-08 17:31:42 -07:00
opcode_test.go Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
README.md Relicense to the btcsuite developers. 2015-05-01 12:00:56 -05:00
reference_test.go Integrate a valid ECDSA signature cache into btcd 2015-10-08 17:31:42 -07:00
script.go txscript: Optimize DisasmString function. 2015-09-28 12:57:53 -05:00
script_test.go txscript: New function IsUnspendable 2015-08-03 10:10:23 -04:00
scriptbuilder.go txscript: Convert to new scriptnum type. 2015-05-01 13:15:08 -05:00
scriptbuilder_test.go txscript: Test consistency and cleanup. 2015-05-04 16:04:29 -05:00
scriptnum.go txscript: Change makeScriptNum to take a length argument 2015-10-05 19:48:55 -04:00
scriptnum_test.go txscript: Change makeScriptNum to take a length argument 2015-10-05 19:48:55 -04:00
sigcache.go Integrate a valid ECDSA signature cache into btcd 2015-10-08 17:31:42 -07:00
sigcache_test.go Integrate a valid ECDSA signature cache into btcd 2015-10-08 17:31:42 -07:00
sign.go Fixed erroneous txscript.KeyClosure documentation. 2015-07-19 16:15:29 +01:00
sign_test.go Integrate a valid ECDSA signature cache into btcd 2015-10-08 17:31:42 -07:00
stack.go txscript: Change makeScriptNum to take a length argument 2015-10-05 19:48:55 -04:00
stack_test.go txscript: Consensus audit. 2015-05-06 09:41:50 -05:00
standard.go switch maxDataCarrierSize to public const 2015-07-20 14:26:05 +08:00
standard_test.go txscript: Test consistency and cleanup. 2015-05-04 16:04:29 -05:00

txscript

[Build Status] (https://travis-ci.org/btcsuite/btcd)

Package txscript implements the bitcoin transaction script language. There is a comprehensive test suite. Package txscript is licensed under the liberal ISC license.

This package has intentionally been designed so it can be used as a standalone package for any projects needing to use or validate bitcoin transaction scripts.

Bitcoin Scripts

Bitcoin provides a stack-based, FORTH-like langauge for the scripts in the bitcoin transactions. This language is not turing complete although it is still fairly powerful. A description of the language can be found at https://en.bitcoin.it/wiki/Script

Documentation

[GoDoc] (http://godoc.org/github.com/btcsuite/btcd/txscript)

Full go doc style documentation for the project can be viewed online without installing this package by using the GoDoc site here.

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/txscript

Installation

$ go get github.com/btcsuite/btcd/txscript

Examples

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 txscript is licensed under the liberal ISC License.