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Author Topic: Python code for validating bitcoin address  (Read 37558 times)
Gavin Andresen
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September 13, 2010, 12:38:24 PM
 #1

This bitcoind address validator is a subclass of the Django forms.CharField class, but could easily be adapted to other frameworks or to be standalone code.

It does a "deep" validation, checking that the checksum built into every bitcoin address matches the address. It needs the PyCrypto library for the SHA256 function.

I hereby release this code into the public domain, do with it what you will.  And please let me know if you find any bugs in it.

BCAddressField.py:
Code:
#
# DJango field type for a Bitcoin Address
#
import re
from django import forms
from django.forms.util import ValidationError
from Crypto.Hash import SHA256

class BCAddressField(forms.CharField):
  default_error_messages = {
    'invalid': 'Invalid Bitcoin address.',
    }

  def __init__(self, *args, **kwargs):
    super(BCAddressField, self).__init__(*args, **kwargs)

  def clean(self, value):
    value = value.strip()
    if re.match(r"[a-zA-Z1-9]{27,35}$", value) is None:
      raise ValidationError(self.error_messages['invalid'])
    version = get_bcaddress_version(value)
    if version is None:
      raise ValidationError(self.error_messages['invalid'])
    return value

import math

__b58chars = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
__b58base = len(__b58chars)

def b58encode(v):
  """ encode v, which is a string of bytes, to base58.                                                                                                              
  """

  long_value = 0L
  for (i, c) in enumerate(v[::-1]):
    long_value += (256**i) * ord(c)

  result = ''
  while long_value >= __b58base:
    div, mod = divmod(long_value, __b58base)
    result = __b58chars[mod] + result
    long_value = div
  result = __b58chars[long_value] + result

  # Bitcoin does a little leading-zero-compression:                                                                                                                  
  # leading 0-bytes in the input become leading-1s                                                                                                                  
  nPad = 0
  for c in v:
    if c == '\0': nPad += 1
    else: break

  return (__b58chars[0]*nPad) + result

def b58decode(v, length):
  """ decode v into a string of len bytes                                                                                                                            
  """
  long_value = 0L
  for (i, c) in enumerate(v[::-1]):
    long_value += __b58chars.find(c) * (__b58base**i)

  result = ''
  while long_value >= 256:
    div, mod = divmod(long_value, 256)
    result = chr(mod) + result
    long_value = div
  result = chr(long_value) + result

  nPad = 0
  for c in v:
    if c == __b58chars[0]: nPad += 1
    else: break

  result = chr(0)*nPad + result
  if length is not None and len(result) != length:
    return None

  return result

def get_bcaddress_version(strAddress):
  """ Returns None if strAddress is invalid.  Otherwise returns integer version of address. """
  addr = b58decode(strAddress,25)
  if addr is None: return None
  version = addr[0]
  checksum = addr[-4:]
  vh160 = addr[:-4] # Version plus hash160 is what is checksummed                                                                                                    
  h3=SHA256.new(SHA256.new(vh160).digest()).digest()
  if h3[0:4] == checksum:
    return ord(version)
  return None
October 20: Fixed bug with bitcoin addresses with leading-1's.

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October 19, 2010, 10:55:32 PM
 #2

Thanks for your code !

Contributing with a Ruby translation (more specifically a Rails drop-in validator)
require 'digest'

class BitcoinAddressValidator < ActiveModel::EachValidator
  def validate(record, field, value)
    unless valid_bitcoin_address?(value)
      record.errors[field] << "Bitcoin address is invalid"
    end
  end

  private

  B58Chars = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
  B58Base = B58Chars.length

  def self.valid_bitcoin_address?(address)
    (address =~ /^[a-zA-Z1-9]{33,35}$/) and version(address)
  end

  def self.version(address)
    decoded = b58_decode(address, 25)
   
    version = decoded[0, 1]
    checksum = decoded[-4, decoded.length]
    vh160 = decoded[0, decoded.length - 4]

    hashed = (Digest::SHA2.new << (Digest::SHA2.new << vh160).digest).digest

    hashed[0, 4] == checksum ? version[0] : nil
  end

  def self.b58_decode(value, length)
    long_value = 0
    index = 0
    result = ""

    value.reverse.each_char do |c|
      long_value += B58Chars.index(c) * (B58Base ** index)
      index += 1
    end

    while long_value >= 256 do
      div, mod = long_value.divmod 256
      result = mod.chr + result
      long_value = div
    end

    result = long_value.chr + result

    if result.length < length
      result = 0.chr * (length - result.length) + result
    end

    result
  end
end


Passes unit tests (see http://github.com/davout/bitcoin-bank)

Just a question, what's the use of your b58_encode method ?

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October 19, 2010, 11:40:42 PM
 #3

 (address =~ /^[a-zA-Z1-9]{33,35}$/) 

You should bear in mind the fact that 1111111111111111111114oLvT2 is a valid Bitcoin address. It has 27 characters. 28,29,30... etc character addresses also exist.

I have mentioned this before in

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Gavin Andresen
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October 20, 2010, 12:43:36 AM
 #4

RE: what's the use of b58_encode?  It is dead code for this use-- bitcointools (where I first implemented this stuff) uses it to translate from binary hash160 to human-readable bitcoin addresses.

RE: 27 character bitcoin addresses:  I'm puzzled.  There's a mismatch between the way bitcoin treats leading zeros (leading 1's when base58 encoded) and the way my python code treats them.

ByteCoin: have you dissected the bitcoin code enough to explain how it decides how many leading zeros to add?  According to my code, '14oLvT2' and '11111111111111111111111111114oLvT2' are the same bitcoin address (corresponding to the public key with a hash of all zero bytes).

But bitcoin only likes the 27-character '1111111111111111111114oLvT2' version.

I'll have to stare at the code some more tomorrow when I'm more awake.

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theymos
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October 20, 2010, 01:50:10 AM
 #5

For every leading 0x00 byte, add a leading 1 (encode). For every leading 1, add a 0x00 byte (decode). For encode, don't accept input that doesn't have an even number of bits (divisible by eight), as this doesn't make sense. For decode, pad leading zeros until you have an even number of bits.

I just check that the output immediately post-DecodeBase58 (including leading zeroes, checksum, versionNumber) is 25 bytes long. I think that Bitcoin does something similar to this.

I made some web tools for dealing with addresses:
http://theymos.ath.cx:64150/q/checkaddress
http://theymos.ath.cx:64150/q/addresstohash
http://theymos.ath.cx:64150/q/hashtoaddress
http://theymos.ath.cx:64150/q/hashpubkey
(Source not public yet.)

1NXYoJ5xU91Jp83XfVMHwwTUyZFK64BoAD
Gavin Andresen
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October 20, 2010, 03:18:17 PM
 #6

Thanks theymos!  I completely missed the leading-zero-bytes become leading-'1'-chars one-for-one.

I fixed the python code in the first message of this thread.

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October 25, 2010, 07:46:52 AM
 #7

Are you working on a Django bitcoin project ? I'm highly interested, thinking about it myself too.

Blog posts about Bitcoin - 1KdRBbhjo72CqKTrFsQed6s9NMrvwvrUkq
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November 15, 2010, 07:01:46 PM
 #8

For those interested, I rewrote base58_encode/base58_decode in PHP, and added a "decode_btc" function (that will return an array containing "version" and "hash" for a given bitcoin address).

This code requires the following php extensions:
  • gmp (for bignum values, we could use bc, or even the php-native implementation in pear, I'm just too lazy and I got gmp installed on all my servers anyway)
  • hash (or mhash, someone could insert a php-native sha256 implementation to fallback to)

Here's the code, largely inspired from the code of the previous authors of this thread:
Code:
<?php
$btc 
decode_btc('1Eym7pyJcaambv8FG4ZoU8A4xsiL9us2zz');
var_dump($btc);
var_dump(encode_btc($btc));
$btc decode_btc('1111111111111111111114oLvT2');
var_dump($btc);
var_dump(encode_btc($btc));

function 
hash_sha256($string) {
  if (
function_exists('hash')) return hash('sha256'$stringtrue);
  if (
function_exists('mhash')) return mhash(MHASH_SHA256$string);
  
// insert native php implementation of sha256 here
  
throw new Exception('Too lazy to fallback when the guy who configured php was lazy too');
}

function 
encode_btc($btc) {
  
$btc chr($btc['version']).pack('H*'$btc['hash']);
  if (
strlen($btc) != 21) return false;
  
$cksum substr(hash_sha256(hash_sha256($btc)), 04);
  return 
base58_encode($btc.$cksum);
}

function 
decode_btc($btc) {
  
$btc base58_decode($btc);
  if (
strlen($btc) != 25) return false// invalid
  
$version ord($btc[0]);
  
$cksum substr($btc, -4);
  
// checksum is double sha256 (take 4 first bytes of result)
  
$good_cksum substr(hash_sha256(hash_sha256(substr($btc0, -4))), 04);
  if (
$cksum != $good_cksum) return false;
  return array(
'version' => $version'hash' => bin2hex(substr($btc120)));
}

function 
base58_encode($string) {
  
$table '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz';

  
$long_value gmp_init(bin2hex($string), 16);

  
$result '';
  while(
gmp_cmp($long_value58) > 0) {
    list(
$long_value$mod) = gmp_div_qr($long_value58);
    
$result .= $table[gmp_intval($mod)];
  }
  
$result .= $table[gmp_intval($long_value)];

  for(
$nPad 0$string[$nPad] == "\0"; ++$nPad);

  return 
str_repeat($table[0], $nPad).strrev($result);
}

function 
base58_decode($string) {
  
$table '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz';
  static 
$table_rev null;
  if (
is_null($table_rev)) {
    
$table_rev = array();
    for(
$i=0;$i<58;++$i$table_rev[$table[$i]]=$i;
  }

  
$l strlen($string);
  
$long_value gmp_init('0');
  for(
$i=0;$i<$l;++$i) {
    
$c=$string[$l-$i-1];
    
$long_value gmp_add($long_valuegmp_mul($table_rev[$c], gmp_pow(58$i)));
  }

  
// php is lacking binary output for gmp
  
$res pack('H*'gmp_strval($long_value16));

  for(
$nPad 0$string[$nPad] == $table[0]; ++$nPad);
  return 
str_repeat("\0"$nPad).$res;
}

This outputs:
Quote
array(2) {
  ["version"]=>
  int(0)
  ["hash"]=>
  string(40) "9955c1b44fa66688d27aaa06ba4ad02c6dd91088"
}
string(34) "1Eym7pyJcaambv8FG4ZoU8A4xsiL9us2zz"
array(2) {
  ["version"]=>
  int(0)
  ["hash"]=>
  string(40) "0000000000000000000000000000000000000000"
}
string(27) "1111111111111111111114oLvT2"


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May 28, 2011, 10:44:52 PM
 #9

  default_error_messages = {
    'invalid': 'Invalid Bitcoin address.',
    }

  def __init__(self, *args, **kwargs):
    super(BCAddressField, self).__init__(*args, **kwargs)

  def clean(self, value):
    value = value.strip()
    if re.match(r"[a-zA-Z1-9]{27,35}$", value) is None:
      raise ValidationError(self.error_messages['invalid'])

Gavin,
I'm trying to understand your usage of default.error_messages (first line in the snippet), vs. self.error_messages (last line in the snippet, above),  in your code.
Does Django somehow link those two together?  Or is that a bug in the code?  (I'm sure this code has been tested a lot since October!)

Seems to me that you should be using the same dictionary in both places.

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May 28, 2011, 11:05:22 PM
 #10


It's kind of frustrating that nobody seems to want to use my bash functions to check bitcoin addresses.

It only requires basic unix tools such as xxd, dc and openssl.

Code:
base58=({1..9} {A..H} {J..N} {P..Z} {a..k} {m..z})
bitcoinregex="^[$(printf "%s" "${base58[@]}")]{34}$"

decodeBase58() {
    local s=$1
    for i in {0..57}
    do s="${s//${base58[i]}/ $i}"
    done
    dc <<< "16o0d${s// /+58*}+f"
}

checksum() {
    xxd -p -r <<<"$1" |
    openssl dgst -sha256 -binary |
    openssl dgst -sha256 -binary |
    xxd -p -c 80 |
    head -c 8
}

checkBitcoinAddress() {
    if [[ "$1" =~ $bitcoinregex ]]
    then
        h=$(decodeBase58 "$1")
        checksum "00${h::${#h}-8}" |
        grep -qi "^${h: -8}$"
    else return 2
    fi
}
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May 29, 2011, 10:10:19 PM
 #11


It's kind of frustrating that nobody seems to want to use my bash functions to check bitcoin addresses.

It only requires basic unix tools such as xxd, dc and openssl.

This is beautiful and concise shell scripting.  Nice job.
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May 29, 2011, 11:09:01 PM
 #12


It's kind of frustrating that nobody seems to want to use my bash functions to check bitcoin addresses.

It only requires basic unix tools such as xxd, dc and openssl.

This is beautiful and concise shell scripting.  Nice job.

Ah, finally!   Thanks!    Cheesy
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November 15, 2012, 02:38:58 PM
 #13

.NET 4.0 version of bitcoin address validation, Translated by YogaFan:

Code:
Imports System.Security.Cryptography
Imports System.Numerics

Module ValidateBitCoinAddress

Function isValidBitcoinAddress(s As String) As Boolean
    Dim regExPattern As String = "[a-zA-Z1-9]{27,35}$"
    If MatchString(s, regExPattern) Then
        If get_bcaddress_version(s) <> "" Then
            isValidBitcoinAddress = True
        Else
            isValidBitcoinAddress = False
        End If
    Else
        isValidBitcoinAddress = False
    End If
End Function


Function MatchString(ByVal str As String, ByVal regexstr As String) As Boolean
    str = str.Trim()
    Dim pattern As New System.Text.RegularExpressions.Regex(regexstr)
    Return pattern.IsMatch(str)
End Function

Function get_bcaddress_version(strAddress) As String

    Dim addr As Byte()
    Dim version As Byte
    Dim checksum(3) As Byte
    Dim h3(3) As Byte
    Dim x As Integer

    addr = b58decode(strAddress, 25)

    If IsNothing(addr) Then
        'fail
        get_bcaddress_version = ""
        Exit Function
    End If

    Dim lenAddr As Integer = addr.GetLength(0)
    Dim vh160(lenAddr - 5) As Byte
    Dim sha As New SHA256Managed()

    version = addr(0)
    checksum = {addr(lenAddr - 4), addr(lenAddr - 3), addr(lenAddr - 2), addr(lenAddr - 1)}

    For x = 0 To vh160.GetLength(0) - 1
        vh160(x) = addr(x)
    Next

    Dim Hash() As Byte = sha.ComputeHash(vh160)
    Dim SecondHash() As Byte = sha.ComputeHash(Hash)

    h3 = {SecondHash(0), SecondHash(1), SecondHash(2), SecondHash(3)}

    If h3(0) = checksum(0) And h3(1) = checksum(1) And h3(2) = checksum(2) And h3(3) = checksum(3) Then
        get_bcaddress_version = version.ToString
    Else
        'fail
        get_bcaddress_version = ""
    End If

End Function

Function b58encode(b() As Byte) As String


    Dim b58chars As String = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"
    Dim b58base As BigInteger = 58
    Dim x As BigInteger
    Dim long_value As BigInteger = 0
    Dim result As String = ""
    Dim iMod As BigInteger = 0
    Dim iDiv As BigInteger = 0
    Dim b256base As BigInteger = 256

    Dim c As Integer
    Dim lv As Integer

    lv = b.GetLength(0) - 1
    c = 0
    For x = lv To 0 Step -1
        long_value = long_value + BigInteger.Pow(b256base, x) * b(c)
        c = c + 1
    Next

    Do While long_value >= b58base
        iMod = long_value Mod b58base
        iDiv = long_value / b58base

        result = b58chars(iMod) & result
        long_value = iDiv
    Loop
    result = b58chars(long_value) & result

    For x = 0 To lv
        If b(x) = CByte(0) Then
            result = b58chars(0) & result
        Else
            Exit For
        End If
    Next

    Return result
    End Function

Function insertat(b As Byte, bArr As Byte(), pos As Integer) As Byte()

    If IsNothing(bArr) Then
        'empty array; return single celled array
        Dim tmpsomeOtherBarr(0) As Byte
        tmpsomeOtherBarr(0) = b
        insertat = tmpsomeOtherBarr
        Exit Function
    End If

    Dim x As Integer
    Dim tmpbArr(bArr.GetLength(0)) As Byte

    If pos = -1 Then
        'insert at end of array
        For x = 0 To bArr.GetLength(0) - 1
            tmpbArr(x) = bArr(x)
        Next
        tmpbArr(bArr.GetLength(0)) = b

        Return tmpbArr
    ElseIf pos = 0 Then
        'insert at beginning
        tmpbArr(0) = b
        For x = 1 To bArr.GetLength(0)
            tmpbArr(x) = bArr(x - 1)
        Next
        Return tmpbArr
    Else
        'insert in the middle
        For x = 0 To pos - 1
            tmpbArr(x) = bArr(x)
        Next
        tmpbArr(pos) = b
        For x = pos + 1 To bArr.GetLength(0)
            tmpbArr(x) = bArr(x)
        Next
        Return tmpbArr

    End If
End Function

Function b58decode(v As String, l As Integer) As Byte()

    Dim b58chars As String = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"
    Dim b58base As BigInteger = 58
    Dim long_value As BigInteger = 0
    Dim lv As Integer
    Dim c As Integer
    Dim x As BigInteger
    Dim biPos As BigInteger = 0
    Dim iMod As BigInteger = 0
    Dim iDiv As BigInteger = 0
    Dim result() As Byte

    lv = Len(v) - 1

    For x = lv To 0 Step -1
        c = c + 1
        biPos = b58chars.IndexOf(Mid(v, c, 1))
        long_value = long_value + BigInteger.Pow(b58base, x) * biPos
    Next

    Do While long_value >= 256
        iMod = long_value Mod 256
        iDiv = long_value / 256
        result = insertat(CByte(iMod), result, 0)
        long_value = iDiv
    Loop
    result = insertat(CByte(long_value), result, 0)

    For x = 1 To Len(v)
        If Mid(v, x, 1) = b58chars(0) Then
            result = insertat(CByte(0), result, 0)
        Else
            Exit For
        End If
    Next

    If l > 0 And result.GetLength(0) <> l Then
        Return Nothing
    Else
        Return result
    End If

End Function

End Module



1YogAFA... (oh, nevermind)
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November 17, 2012, 10:03:13 AM
 #14

I too have PHP and Java code for validating and generating Bitcoin addresses that have been tested and known to work.

PHP Example Link: https://github.com/Xenland/Bitcoin-Pseudocode-Client/blob/gh-pages/examples/php/verify_bitcoin_address.php

Java Example Source Link: https://github.com/Xenland/Bitcoin-Pseudocode-Client/blob/gh-pages/examples/java/Commandline%20Generate%20Bitcoin%20Address/src/commandline/CommandLine.java

I Also have an English explanation of how to verify a Bitcoin address (Part of the Bitcoin Pseudocode client project)
http://xenland.github.com/Bitcoin-Pseudocode-Client/verifyaddress.html
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November 27, 2012, 05:18:21 PM
 #15

For those interested, I rewrote base58_encode/base58_decode in PHP, and added a "decode_btc" function (that will return an array containing "version" and "hash" for a given bitcoin address).

This code requires the following php extensions:
  • gmp (for bignum values, we could use bc, or even the php-native implementation in pear, I'm just too lazy and I got gmp installed on all my servers anyway)
  • hash (or mhash, someone could insert a php-native sha256 implementation to fallback to)

Here's the code, largely inspired from the code of the previous authors of this thread:
Code:
<?php
$btc 
decode_btc('1Eym7pyJcaambv8FG4ZoU8A4xsiL9us2zz');
var_dump($btc);
var_dump(encode_btc($btc));
$btc decode_btc('1111111111111111111114oLvT2');
var_dump($btc);
var_dump(encode_btc($btc));

function 
hash_sha256($string) {
  if (
function_exists('hash')) return hash('sha256'$stringtrue);
  if (
function_exists('mhash')) return mhash(MHASH_SHA256$string);
  
// insert native php implementation of sha256 here
  
throw new Exception('Too lazy to fallback when the guy who configured php was lazy too');
}

function 
encode_btc($btc) {
  
$btc chr($btc['version']).pack('H*'$btc['hash']);
  if (
strlen($btc) != 21) return false;
  
$cksum substr(hash_sha256(hash_sha256($btc)), 04);
  return 
base58_encode($btc.$cksum);
}

function 
decode_btc($btc) {
  
$btc base58_decode($btc);
  if (
strlen($btc) != 25) return false// invalid
  
$version ord($btc[0]);
  
$cksum substr($btc, -4);
  
// checksum is double sha256 (take 4 first bytes of result)
  
$good_cksum substr(hash_sha256(hash_sha256(substr($btc0, -4))), 04);
  if (
$cksum != $good_cksum) return false;
  return array(
'version' => $version'hash' => bin2hex(substr($btc120)));
}

function 
base58_encode($string) {
  
$table '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz';

  
$long_value gmp_init(bin2hex($string), 16);

  
$result '';
  while(
gmp_cmp($long_value58) > 0) {
    list(
$long_value$mod) = gmp_div_qr($long_value58);
    
$result .= $table[gmp_intval($mod)];
  }
  
$result .= $table[gmp_intval($long_value)];

  for(
$nPad 0$string[$nPad] == "\0"; ++$nPad);

  return 
str_repeat($table[0], $nPad).strrev($result);
}

function 
base58_decode($string) {
  
$table '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz';
  static 
$table_rev null;
  if (
is_null($table_rev)) {
    
$table_rev = array();
    for(
$i=0;$i<58;++$i$table_rev[$table[$i]]=$i;
  }

  
$l strlen($string);
  
$long_value gmp_init('0');
  for(
$i=0;$i<$l;++$i) {
    
$c=$string[$l-$i-1];
    
$long_value gmp_add($long_valuegmp_mul($table_rev[$c], gmp_pow(58$i)));
  }

  
// php is lacking binary output for gmp
  
$res pack('H*'gmp_strval($long_value16));

  for(
$nPad 0$string[$nPad] == $table[0]; ++$nPad);
  return 
str_repeat("\0"$nPad).$res;
}

This outputs:
Quote
array(2) {
  ["version"]=>
  int(0)
  ["hash"]=>
  string(40) "9955c1b44fa66688d27aaa06ba4ad02c6dd91088"
}
string(34) "1Eym7pyJcaambv8FG4ZoU8A4xsiL9us2zz"
array(2) {
  ["version"]=>
  int(0)
  ["hash"]=>
  string(40) "0000000000000000000000000000000000000000"
}
string(27) "1111111111111111111114oLvT2"



Thanks for sharing this source! I've used your implementation, but I noticed some addresses don't validate. For example: 12HzMcHURwmAxAkfWgtktYsF3vRTkBz4F3 Any thoughts on why?

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grondilu
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November 27, 2012, 07:23:50 PM
 #16


Has anyone written a test-suite for key generation-validation?

I mean, a text/json/whatever file where you'd have a couple of address/private key pairs?

And in all possible formats (test network, compressed/uncompressed and so on...).

That would be useful.
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November 27, 2012, 08:00:11 PM
 #17


Has anyone written a test-suite for key generation-validation?

I mean, a text/json/whatever file where you'd have a couple of address/private key pairs?

And in all possible formats (test network, compressed/uncompressed and so on...).

That would be useful.

There is some JSON test data at https://github.com/bitcoin/bitcoin/tree/master/src/test/data

I'm using this for a C-based "libccoin" bitcoin library testing https://github.com/jgarzik/picocoin/


Jeff Garzik, bitcoin core dev team and BitPay engineer; opinions are my own, not my employer.
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November 27, 2012, 11:59:25 PM
 #18

By the way I've created a rosetta code draft task for validating a bitcoin address:

http://rosettacode.org/wiki/Bitcoin/address_validation

Don't hesitate to put your solution in your language.   But please make it short.
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November 28, 2012, 01:05:54 AM
 #19


Thanks!
matmar10
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November 28, 2012, 09:02:58 AM
 #20

I too have PHP and Java code for validating and generating Bitcoin addresses that have been tested and known to work.

PHP Example Link: https://github.com/Xenland/Bitcoin-Pseudocode-Client/blob/gh-pages/examples/php/verify_bitcoin_address.php

Java Example Source Link: https://github.com/Xenland/Bitcoin-Pseudocode-Client/blob/gh-pages/examples/java/Commandline%20Generate%20Bitcoin%20Address/src/commandline/CommandLine.java

I Also have an English explanation of how to verify a Bitcoin address (Part of the Bitcoin Pseudocode client project)
http://xenland.github.com/Bitcoin-Pseudocode-Client/verifyaddress.html


Thanks for this contribution! I ran the test fixtures for valid and invalid public keys listed below, with a few of my own known keys added; I got the following result:

There was 1 failure:

1) Lmh\BitcoinTransferBundle\Tests\BitcoinAddressValidatorTest::testInvalid
Test invalid public key '37qgekLpCCHrQuSjvX3fs496FWTGsHFHizjJAs6NPcR47aefnnCWECAhHV6E3g4YN7u7Yuwod5Y' returns 1 error.
Failed asserting that 0 matches expected 1.

/Users/matmar10/Projects/bitcoinbymobile/src/Lmh/BitcoinTransferBundle/Tests/BitcoinAddressValidatorTest.php:69

FAILURES!
Tests: 2, Assertions: 22, Failures: 1.

By the way, your PHP code had an undefined variable throwing an error and also an unused variable; I'll send you a git push request.

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http://www.bitcoinbymobile.com
----
"pecunia, si uti scis, ancilla est; si nescis, domina"
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