blockparser

Credits

Written by znort987@yahoo.com If you find this useful: 1ZnortsoStC1zSTXbW6CUtkvqew8czMMG

What

A fairly fast, quick and dirty bitcoin whole blockchain parser.

Why

• Few dependencies: openssl-dev, boost, libsparsehash-dev
• Very quickly extract information from the entire blockchain.
• Code is simple and helps to understand how the data structure underlying bitcoin works.

Build it

• Turn your x86-64 Ubuntu box on
• Make sure you have an up to date satoshi client blockchain in ~/.bitcoin
• Run this:

sudo apt-get install libssl-dev build-essential g++-4.4 git-core perl sudo apt-get install libboost-all-dev libsparsehash-dev git clone git://github.com/jcomeauictx/blockparser.git cd blockparser make

Try it

• Compute simple blockchain stats, full chain parse (< 1 second) ./parser simpleStats
• Extract all transactions for popular address 1dice6wBxymYi3t94heUAG6MpG5eceLG1 ./parser transactions 06f1b66fa14429389cbffa656966993eab656f37
• Compute the closure of an address, that is the list of addresses that provably belong to the same person: ./parser closure 06f1b66fa14429389cbffa656966993eab656f37
• Compute and print the balance for all keys ever used in a TX since the beginning of time: ./parser allBalances >allBalances.txt
• See how much of the BTC 10K pizza tainted each of the TX in the chain ./parser taint >pizzaTaint.txt
• See all the block rewards and fees: ./parser rewards >rewards.txt
• See a greatly detailed dump of the pizza transaction ./parser show

Caveats

• You need an x86-84 Debian or Ubuntu box and a recent version of GCC(>=4.4), recent versions of boost and openssl-dev. The whole thing is very unlikely to work or even compile on anything else.
• It needs quite a bit of RAM to work. Never exactly measured how much, but the hash maps will grow quite fat. I might switch them to something different that spills over to disk at some point. For now: it works fine with 8 Gigs.
• The code isn't particularly clean or well architected. It was just a quick way for me to learn about bitcoin. There isnt much in the way of comments either.
• OTOH, it is fairly simple, short, and efficient. If you want to understand how the blockchain data structure works, the code in parser.cpp is a solid way to start.

Hacking the code

• parser.cpp contains a generic parser that mmaps the blockchain, parses it and calls "user-defined" callbacks as it hits interesting bits of information.

• util.cpp contains a grab-bag of useful bitcoin related routines. Interesting examples include: showScript getBaseReward solveOutputScript decompressPublicKey

• cb/allBalances.cpp: all balance of all addresses.

• cb/closure.cpp: compute the transitive closure of an address

• cb/csv.cpp: product a CSV dump of the blockchain

• cb/dumpTX.cpp: display a transaction in very great detail

• cb/help.cpp: dump detailed help for all other commands

• cb/pristine.cpp: show all "pristine" (i.e. unspent) blocks

• cb/rewards.cpp: show all block rewards (including fees)

• cb/simpleStats.cpp: compute simple stats.

• cb/sql.cpp: produce an SQL dump of the blockchain

• cb/taint.cpp: compute the taint from a given TX to all TXs.

• cb/transactions.cpp: extract all transactions containing an address.

• You can very easily add your own custom command. You can use the existing callbacks in directory ./cb/ as a template to build your own:

  • cp cb/allBalances.cpp cb/myExtractor.cpp
  • Hack away
  • Recompile
  • Run

• You can also read the file callback.h (the base class from which you derive to implement your own new commands). It has been heavily commented and should provide a good basis to pick what to overload to achieve your goal.

• The code makes heavy use of the google dense hash maps. You can switch it to use sparse hash maps (see util.h, search for: DENSE, undef it). Sparse hash maps are slower but save quite a bit of RAM.

License

Code is in the public domain.