btctool

A multi-tool for Bitcoin keys and addresses, written in C++ with minimal dependencies.

Functionality:

• Encode and decode arbitrary data in Base16, Base64, and Base58Check.
• Hash using SHA-256 and RIPEMD-160.
• Disassemble Bitcoin Script.
• Construct private key from provided bits.
• Encrypt and decrypt private key per BIP38.
• Derive public key from private key.
• Derive P2PKH address from public key.
• Derive P2SH multi-sig address from public keys.
• Derive private keys from private seed.
• Derive public keys from public seed.
• Derive P2PKH addresses from public seed.
• Derive P2SH multi-sig addresses from public seeds.

Applets can accept their inputs either as command-line arguments or via standard input.

Specifying private keys via the command line poses a security risk on multi-user hosts. Private keys should be specified via standard input for greatest security.

Building

1. Install dependencies:

   • GMP — The GNU Multiple Precision Arithmetic Library

   Gentoo: # emerge -n dev-libs/gmp
   Ubuntu: $ sudo apt-get install build-essential libgmp-dev

2. Check out sources:

    $ git clone --recursive https://github.com/whitslack/btctool.git
    $ cd btctool
   

3. Build:

    $ make
    $ cd out/"$(gcc -dumpmachine)"
   

Usage

encode16

usage:
  encode16
    Encode stdin to hex.

$ echo 'Hello world!' | ./btctool encode16
48656c6c6f20776f726c64210a

decode16

usage:
  decode16 [<hex>]
    Decode hex from stdin or argument.

$ ./btctool decode16 48656c6c6f20776f726c64210a
Hello world!

$ echo 48656c6c6f20776f726c64210a | ./btctool decode16
Hello world!

encode64

usage:
  encode64 [<hex>]
    Encode stdin or argument to Base64.

$ echo 'Hello world!' | ./btctool encode64
SGVsbG8gd29ybGQhCg==

$ ./btctool encode64 48656c6c6f20776f726c64210a
SGVsbG8gd29ybGQhCg==

decode64

usage:
  decode64 [<base64>]
    Decode Base64 from stdin or argument.

$ ./btctool decode64 SGVsbG8gd29ybGQhCg==
Hello world!

$ echo SGVsbG8gd29ybGQhCg== | ./btctool decode64
Hello world!

encode58

usage:
  encode58 [<hex>]
    Encode stdin or argument to Base58Check.

$ echo 'Hello world!' | ./btctool encode58
gTazoqFi2U9CKLR6zpJ8CEV

$ ./btctool encode58 48656c6c6f20776f726c64210a
gTazoqFi2U9CKLR6zpJ8CEV

decode58

usage:
  decode58 [<base58>]
    Decode Base58Check from stdin or argument.

$ ./btctool decode58 gTazoqFi2U9CKLR6zpJ8CEV
Hello world!

$ echo gTazoqFi2U9CKLR6zpJ8CEV | ./btctool decode58
Hello world!

disasm

usage:
  disasm [<script>]
    Disassemble hex script from stdin or argument.

$ ./btctool disasm 76a914c4c5d791fcb4654a1ef5e03fe0ad3d9c598f982788ac
OP_DUP OP_HASH160 0xc4c5d791fcb4654a1ef5e03fe0ad3d9c598f9827 OP_EQUALVERIFY OP_CHECKSIG

$ echo 76a914c4c5d791fcb4654a1ef5e03fe0ad3d9c598f982788ac | ./btctool disasm
OP_DUP OP_HASH160 0xc4c5d791fcb4654a1ef5e03fe0ad3d9c598f9827 OP_EQUALVERIFY OP_CHECKSIG

sha256

usage:
  sha256 [<hex>]
    Hash stdin or argument using SHA-256.

$ echo 'Hello world!' | ./btctool sha256
0ba904eae8773b70c75333db4de2f3ac45a8ad4ddba1b242f0b3cfc199391dd8

$ ./btctool sha256 48656c6c6f20776f726c64210a
0ba904eae8773b70c75333db4de2f3ac45a8ad4ddba1b242f0b3cfc199391dd8

rmd160

usage:
  rmd160 [<hex>]
    Hash stdin or argument using RIPEMD-160.

$ echo 'Hello world!' | ./btctool rmd160
31bc8e633097159a704659964eadf48dd776e2c0

$ ./btctool rmd160 48656c6c6f20776f726c64210a
31bc8e633097159a704659964eadf48dd776e2c0

privkey

usage:
  privkey [<hex>]
    Derive private key from stdin or argument.

$ ./btctool privkey < /dev/random
L3p8oAcQTtuokSCRHQ7i4MhjWc9zornvpJLfmg62sYpLRJF9woSu

$ ./btctool privkey c4bbcb1fbec99d65bf59d85c8cb62ee2db963f0fe106f483d9afa73bd4e39a8a
L3p8oAcQTtuokSCRHQ7i4MhjWc9zornvpJLfmg62sYpLRJF9woSu

$ ./btctool privkey "$(echo -n 'correct horse battery staple' | ./btctool sha256)"
L3p8oAcQTtuokSCRHQ7i4MhjWc9zornvpJLfmg62sYpLRJF9woSu

pubkey

usage:
  pubkey [<privkey>]
    Derive public key from private key.

$ ./btctool pubkey L3p8oAcQTtuokSCRHQ7i4MhjWc9zornvpJLfmg62sYpLRJF9woSu
0378d430274f8c5ec1321338151e9f27f4c676a008bdf8638d07c0b6be9ab35c71

$ echo L3p8oAcQTtuokSCRHQ7i4MhjWc9zornvpJLfmg62sYpLRJF9woSu | ./btctool pubkey
0378d430274f8c5ec1321338151e9f27f4c676a008bdf8638d07c0b6be9ab35c71

address

P2PKH:

usage:
  address [<pubkey>]
    Derive address from public key.

$ ./btctool address 0378d430274f8c5ec1321338151e9f27f4c676a008bdf8638d07c0b6be9ab35c71
1C7zdTfnkzmr13HfA2vNm5SJYRK6nEKyq8

$ echo 0378d430274f8c5ec1321338151e9f27f4c676a008bdf8638d07c0b6be9ab35c71 | ./btctool address
1C7zdTfnkzmr13HfA2vNm5SJYRK6nEKyq8

You can verify the address produced by this command by manually hashing the public key and encoding its digest:

$ ./btctool encode58 "00$(./btctool rmd160 "$(./btctool sha256 0378d430274f8c5ec1321338151e9f27f4c676a008bdf8638d07c0b6be9ab35c71)")"
1C7zdTfnkzmr13HfA2vNm5SJYRK6nEKyq8

P2SH multi-sig:

usage:
  address <m> [<pubkey>...]
    Derive m-of-n P2SH address from public keys.

$ ./btctool address 1 \
	0378d430274f8c5ec1321338151e9f27f4c676a008bdf8638d07c0b6be9ab35c71 \
	02ea7e5f909d33216c744c02173f322ef4d87a3b7cedb4d407f8a258dde24502d6
3GYVbmYjeoHhHb4svsJeoERHMseupd8ReA

$ { echo 0378d430274f8c5ec1321338151e9f27f4c676a008bdf8638d07c0b6be9ab35c71
	echo 02ea7e5f909d33216c744c02173f322ef4d87a3b7cedb4d407f8a258dde24502d6 ; } |
	./btctool address 1
3GYVbmYjeoHhHb4svsJeoERHMseupd8ReA

$ ./btctool address 1 \
	"$(./btctool pubkey "$(./btctool privkey "$(echo -n 'correct horse battery staple' | ./btctool sha256)")")" \
	"$(./btctool pubkey "$(./btctool privkey "$(echo -n 'opensesame' | ./btctool sha256)")")"
3GYVbmYjeoHhHb4svsJeoERHMseupd8ReA

encrypt

usage:
  encrypt [<privkey>]
    Encrypt private key per BIP38.

$ ./btctool encrypt L3p8oAcQTtuokSCRHQ7i4MhjWc9zornvpJLfmg62sYpLRJF9woSu
Enter passphrase (not echoed):
6PYLr7QZWi5wipwCNgQKfJwqQeBQ6JnLVbz3sZceYRhf1yWZeTDy17CEGD

$ echo 'opensesame' | ./btctool encrypt L3p8oAcQTtuokSCRHQ7i4MhjWc9zornvpJLfmg62sYpLRJF9woSu
6PYLr7QZWi5wipwCNgQKfJwqQeBQ6JnLVbz3sZceYRhf1yWZeTDy17CEGD

$ { ./btctool privkey c4bbcb1fbec99d65bf59d85c8cb62ee2db963f0fe106f483d9afa73bd4e39a8a
	echo 'opensesame' ; } | ./btctool encrypt
6PYLr7QZWi5wipwCNgQKfJwqQeBQ6JnLVbz3sZceYRhf1yWZeTDy17CEGD

decrypt

usage:
  decrypt [<privkey>]
    Decrypt private key per BIP38.

$ ./btctool decrypt 6PYLr7QZWi5wipwCNgQKfJwqQeBQ6JnLVbz3sZceYRhf1yWZeTDy17CEGD
Enter passphrase (not echoed):
L3p8oAcQTtuokSCRHQ7i4MhjWc9zornvpJLfmg62sYpLRJF9woSu

$ echo 'opensesame' | ./btctool decrypt 6PYLr7QZWi5wipwCNgQKfJwqQeBQ6JnLVbz3sZceYRhf1yWZeTDy17CEGD
L3p8oAcQTtuokSCRHQ7i4MhjWc9zornvpJLfmg62sYpLRJF9woSu

$ { echo 6PYLr7QZWi5wipwCNgQKfJwqQeBQ6JnLVbz3sZceYRhf1yWZeTDy17CEGD
	echo 'opensesame' ; } | ./btctool decrypt
L3p8oAcQTtuokSCRHQ7i4MhjWc9zornvpJLfmg62sYpLRJF9woSu

privkeys

usage:
  privkeys <k> [<privseed>]
    Derive k private keys from private seed.

$ ./btctool privkeys 3 L3p8oAcQTtuokSCRHQ7i4MhjWc9zornvpJLfmg62sYpLRJF9woSu
Kyqisrs8E2MwqoB5AeWinAiELDCEoTVjkiWgNyiSxtHWkDdtUx89
KzUXcQjTvSBN1399VDhe1xpNDcC6k9dq96NgSTtz8BqWcXQ3G2oL
L1k95WU9KFpCKX5J8N5UVZ2dzQBpdXv1ur6gZSG4SnwWM8sm45yc

$ echo L3p8oAcQTtuokSCRHQ7i4MhjWc9zornvpJLfmg62sYpLRJF9woSu | ./btctool privkeys 3
Kyqisrs8E2MwqoB5AeWinAiELDCEoTVjkiWgNyiSxtHWkDdtUx89
KzUXcQjTvSBN1399VDhe1xpNDcC6k9dq96NgSTtz8BqWcXQ3G2oL
L1k95WU9KFpCKX5J8N5UVZ2dzQBpdXv1ur6gZSG4SnwWM8sm45yc

pubkeys

usage:
  pubkeys <k> [<pubseed>]
    Derive k public keys from public seed.

$ ./btctool pubkeys 3 0378d430274f8c5ec1321338151e9f27f4c676a008bdf8638d07c0b6be9ab35c71
03d2cd68564c61d49e86b76b16bb86b605e3ffae37ad04992540b3a91b1404caf8
02ca341396eb0e90cd99b6b396308c8acfedca8382e58898e4cae58a1c814aa6ba
03d49806dc2c3fa8a27d3451ccfdbd1144d2c09d9c72bd0ba9e4d5f68eddb9f80f

$ echo 0378d430274f8c5ec1321338151e9f27f4c676a008bdf8638d07c0b6be9ab35c71 | ./btctool pubkeys 3
03d2cd68564c61d49e86b76b16bb86b605e3ffae37ad04992540b3a91b1404caf8
02ca341396eb0e90cd99b6b396308c8acfedca8382e58898e4cae58a1c814aa6ba
03d49806dc2c3fa8a27d3451ccfdbd1144d2c09d9c72bd0ba9e4d5f68eddb9f80f

You can verify that the public keys produced by this command indeed correspond one-to-one with the private keys produced by the privkeys command:

$ for privkey in $(./btctool privkeys 3 L3p8oAcQTtuokSCRHQ7i4MhjWc9zornvpJLfmg62sYpLRJF9woSu) ; do
	./btctool pubkey "${privkey}" ; done
03d2cd68564c61d49e86b76b16bb86b605e3ffae37ad04992540b3a91b1404caf8
02ca341396eb0e90cd99b6b396308c8acfedca8382e58898e4cae58a1c814aa6ba
03d49806dc2c3fa8a27d3451ccfdbd1144d2c09d9c72bd0ba9e4d5f68eddb9f80f

addresses

P2PKH:

usage:
  addresses <k> [<pubseed>]
    Derive k addresses from public seed.

$ ./btctool addresses 3 0378d430274f8c5ec1321338151e9f27f4c676a008bdf8638d07c0b6be9ab35c71
16MqnKxF7WNsGG7Aksn2d982uLe6NjpCq6
13SUk8ySvnUoWiHyG3bydEtGrfyaJNJ5wT
19r3Mjh1krhFybuV9RjmR2nuM9WJvbH75F

$ echo 0378d430274f8c5ec1321338151e9f27f4c676a008bdf8638d07c0b6be9ab35c71 | ./btctool addresses 3
16MqnKxF7WNsGG7Aksn2d982uLe6NjpCq6
13SUk8ySvnUoWiHyG3bydEtGrfyaJNJ5wT
19r3Mjh1krhFybuV9RjmR2nuM9WJvbH75F

You can verify that the addresses produced by this command indeed correspond one-to-one with the public keys produced by the pubkeys command:

$ for pubkey in $(./btctool pubkeys 3 0378d430274f8c5ec1321338151e9f27f4c676a008bdf8638d07c0b6be9ab35c71) ; do
	./btctool address "${pubkey}" ; done
16MqnKxF7WNsGG7Aksn2d982uLe6NjpCq6
13SUk8ySvnUoWiHyG3bydEtGrfyaJNJ5wT
19r3Mjh1krhFybuV9RjmR2nuM9WJvbH75F

P2SH multi-sig:

usage:
  addresses <k> <m> [<pubseed>...]
    Derive k m-of-n P2SH addresses from public seeds.

$ ./btctool addresses 3 1 \
	0378d430274f8c5ec1321338151e9f27f4c676a008bdf8638d07c0b6be9ab35c71 \
	02ea7e5f909d33216c744c02173f322ef4d87a3b7cedb4d407f8a258dde24502d6
3Moyic1GdKfbp8ThFkzg1p84QZWtrVRE8k
3LSCy5vN9qZ9QPLLMn7xoQxCoD1zix2uMJ
3LTe2vn5m6ydshPywAfedEqekTgtgYAmvo

$ { echo 0378d430274f8c5ec1321338151e9f27f4c676a008bdf8638d07c0b6be9ab35c71
	echo 02ea7e5f909d33216c744c02173f322ef4d87a3b7cedb4d407f8a258dde24502d6 ; } |
	./btctool addresses 3 1
3Moyic1GdKfbp8ThFkzg1p84QZWtrVRE8k
3LSCy5vN9qZ9QPLLMn7xoQxCoD1zix2uMJ
3LTe2vn5m6ydshPywAfedEqekTgtgYAmvo

You can verify that the addresses produced by this command indeed correspond one-to-one with the public keys produced by the pubkeys command:

$ while read -r pubkey1 <&3 && read -r pubkey2 <&4 ; do
	./btctool address 1 "${pubkey1}" "${pubkey2}" ; done \
	3< <(./btctool pubkeys 3 0378d430274f8c5ec1321338151e9f27f4c676a008bdf8638d07c0b6be9ab35c71) \
	4< <(./btctool pubkeys 3 02ea7e5f909d33216c744c02173f322ef4d87a3b7cedb4d407f8a258dde24502d6)
3Moyic1GdKfbp8ThFkzg1p84QZWtrVRE8k
3LSCy5vN9qZ9QPLLMn7xoQxCoD1zix2uMJ
3LTe2vn5m6ydshPywAfedEqekTgtgYAmvo