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Satoshi holding more than his 1M Bitcoins (e.g. 10 M ) would be retarded.
BTC would drop and everyone would lose.
Not all about Bitcoin is Decentralized,because we are all is central and this all goes because of human resources. We have the prosuder to use Bitcoin as a tool of our trade, pay a fee and wait for the confirmation where we've accept it so far. We have the rule, something like Bitcoin has a coins supply of block turnover released from the mining process,and more systematic rules is be made in order to have the concept of Bitcoin. Pure of Bitcoin itself have the protocol of Bitcoin their requires consensus. The consensus is we are all that was empowering blockchain, we are who running node, we are who the miners free to mine, we are who clients that only do transactions and also not inseparable from those in the market circulation, researchers, developers and all parties involved but we had to walk in the same protocol to provide consensus. Hardfork will only damage existing fundamentally and continue to rearrange the existing consensus.Not to concern in increase blocksize or corporations although they could give Bitcoin remain decentralized,simply we must still have The core that maintains fundamental and provide space to all do research without destroying the fundamentals that made us solid all this time. Problem of crime using bitcoin is same problem facing to any currencies,that problem is more as duty of government to protect us as the people live in country, we just have to do all we can do at this problem . This is not being talking about theory, even the theory could make nothing to something, this just do something for what we care. we must stand together developers so that they also stand to one another and we are all be solid together. add : for issue&gossip maker I absolutely not SN, but my respect always here to him. thanks .. EDIT: whether we've set a minimum block based on the occurrence of transactions per 10 minutes ,are we can focus more on the features of the future too .. |
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nice ,very helpful for newbie like me . thanks
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Was it this exact script? Wouldnt that make Casascius coins vulnerable to a brute force attack if a insufficient entropy source was used?
impossible. Mini key keep using SHA256 . So? If I SHA256 all numbers from 0 to 127 and give you a single hash you could just brute force the number to it. IF - and that was my question - random number generator was indeed insufficient it might be vulnerable to the same attack. The range would obviously be bigger, but the question is if its big enough to make an attack unfeasible. i think this is out off topic.  are you guessing me trying to brute force ? I answer yes .  but , in practice it is still not possible in accordance with that we want to brute force,. Python 2.7.10 (default, May 23 2015, 09:40:32) [MSC v.1500 32 bit (Intel)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> pow(2,160)
1461501637330902918203684832716283019655932542976L
>>>pow(2,53)
9007199254740992L
>>> pow(2,256)
115792089237316195423570985008687907853269984665640564039457584007913129639936L
2 53 is possible to attack, maybe not for you, but its possible. Anyway, see my edit, it was not this exact script that was used, but just something like this. i see. in this case . The mini private key format offers a simple typo check code. Mini private keys must be generated in a "brute force" fashion, keeping only keys that conform to the format's rules. If a key is well-formed (30 Base58 characters starting with S), but fails the hash check, then it probably contains a typo. $ echo -n "S7c64uJjYpFtp2GrEc3RFaVyzJaJoN?" | shasum -a 256
00c7e27df362561ffeffe1653b1c01cc1e44a07e8e547da151773fb5758fc41f *-
If the SHA256 hash of the string followed by '?' doesn't result in something that begins with 0x00, the string is not a valid mini private key. so not just randoming key to qualify as mini key .they still use SHA256 as a key. |
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Was it this exact script? Wouldnt that make Casascius coins vulnerable to a brute force attack if a insufficient entropy source was used?
impossible. Mini key keep using SHA256 . So? If I SHA256 all numbers from 0 to 127 and give you a single hash you could just brute force the number to it. IF - and that was my question - random number generator was indeed insufficient it might be vulnerable to the same attack. The range would obviously be bigger, but the question is if its big enough to make an attack unfeasible. i think this is out off topic. are you guessing me trying to brute force ? I answer yes . but , in practice it is still not possible in accordance with that we want to brute force,. Python 2.7.10 (default, May 23 2015, 09:40:32) [MSC v.1500 32 bit (Intel)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> pow(2,160)
1461501637330902918203684832716283019655932542976L
>>>pow(2,53)
9007199254740992L
>>> pow(2,256)
115792089237316195423570985008687907853269984665640564039457584007913129639936L
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Was it this exact script? Wouldnt that make Casascius coins vulnerable to a brute force attack if a insufficient entropy source was used?
impossible. Mini key keep using SHA256 . |
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it work ,  >>> from key import *
>>> GenerateKeys()
S7c64uJjYpFtp2GrEc3RFaVyzJaJoN
SHA256( ): e505c601b721b32c0b9b13bff24432ced1e8d37173d89de345cbd6a1b3a09605
sha256(?): 00c7e27df362561ffeffe1653b1c01cc1e44a07e8e547da151773fb5758fc41f
Validated.
Thank you to all of you,i was just trying the same way |
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This is a Python script for generating the "mini" private key used on Casascius coins. The first step is not to use it, as Python's random function is: "is completely unsuitable for cryptographic purposes" (which you can read right above the code snippet on https://en.bitcoin.it/wiki/Mini_private_key_format#Creating_mini_private_keys - you would need someone to harden the crypto in the code first. Was it this exact script? Wouldnt that make Casascius coins vulnerable to a brute force attack if a insufficient entropy source was used? Mini key also has a much smaller keyspace than a full-size private key, and therefore is not as cryptographically strong, although reversing this key space is still hard. To run it, you just install Python 2 (Mac OSX and Linux will already have python), save the script as a file like "minikey.py", and run it with a command python minikey.pyIt needs one more line at the end to call the "main" function: GenerateKeys()still not work Python 2.7.10 (default, May 23 2015, 09:40:32) [MSC v.1500 32 bit (Intel)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import key
>>> GenerateKeys()
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
NameError: name 'GenerateKeys' is not defined
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how it can work for me? import random
import hashlib
BASE58 = '23456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
def Candidate():
"""
Generate a random, well-formed mini private key.
"""
return('%s%s' % ('S', ''.join(
[BASE58[ random.randrange(0,len(BASE58)) ] for i in range(29)])))
def GenerateKeys(numKeys = 10):
"""
Generate mini private keys and output the mini key as well as the full
private key. numKeys is The number of keys to generate, and
"""
keysGenerated = 0
totalCandidates = 0
while keysGenerated < numKeys:
try:
cand = Candidate()
# Do typo check
t = '%s?' % cand
# Take one round of SHA256
candHash = hashlib.sha256(t).digest()
# Check if the first eight bits of the hash are 0
if candHash[0] == '\x00':
privateKey = GetPrivateKey(cand)
print('\n%s\nSHA256( ): %s\nsha256(?): %s' %
(cand, privateKey, candHash.encode('hex_codec')))
if CheckShortKey(cand):
print('Validated.')
else:
print('Invalid!')
keysGenerated += 1
totalCandidates += 1
except KeyboardInterrupt:
break
print('\n%s: %i\n%s: %i\n%s: %.1f' %
('Keys Generated', keysGenerated,
'Total Candidates', totalCandidates,
'Reject Percentage',
100*(1.0-keysGenerated/float(totalCandidates))))
def GetPrivateKey(shortKey):
"""
Returns the hexadecimal representation of the private key corresponding
to the given short key.
"""
if CheckShortKey(shortKey):
return hashlib.sha256(shortKey).hexdigest()
else:
print('Typo detected in private key!')
return None
def CheckShortKey(shortKey):
"""
Checks for typos in the short key.
"""
if len(shortKey) != 30:
return False
t = '%s?' % shortKey
tHash = hashlib.sha256(t).digest()
# Check to see that first byte is \x00
if tHash[0] == '\x00':
return True
return False
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