ZeroNet/src/lib/BitcoinECC/BitcoinECC.py

467 lines
13 KiB
Python

# By: HurlSly
# Source: https://github.com/HurlSly/Python/blob/master/BitcoinECC.py
# Modified: random number generator in def GeneratePrivateKey(self):
import random
import hashlib
import os
class GaussInt:
#A class for the Gauss integers of the form a + b sqrt(n) where a,b are integers.
#n can be positive or negative.
def __init__(self,x,y,n,p=0):
if p:
self.x=x%p
self.y=y%p
self.n=n%p
else:
self.x=x
self.y=y
self.n=n
self.p=p
def __add__(self,b):
return GaussInt(self.x+b.x,self.y+b.y,self.n,self.p)
def __sub__(self,b):
return GaussInt(self.x-b.x,self.y-b.y,self.n,self.p)
def __mul__(self,b):
return GaussInt(self.x*b.x+self.n*self.y*b.y,self.x*b.y+self.y*b.x,self.n,self.p)
def __div__(self,b):
return GaussInt((self.x*b.x-self.n*self.y*b.y)/(b.x*b.x-self.n*b.y*b.y),(-self.x*b.y+self.y*b.x)/(b.x*b.x-self.n*b.y*b.y),self.n,self.p)
def __eq__(self,b):
return self.x==b.x and self.y==b.y
def __repr__(self):
if self.p:
return "%s+%s (%d,%d)"%(self.x,self.y,self.n,self.p)
else:
return "%s+%s (%d)"%(self.x,self.y,self.n)
def __pow__(self,n):
b=Base(n,2)
t=GaussInt(1,0,self.n)
while b:
t=t*t
if b.pop():
t=self*t
return t
def Inv(self):
return GaussInt(self.x/(self.x*self.x-self.n*self.y*self.y),-self.y/(self.x*self.x-self.n*self.y*self.y),self.n,self.p)
def Cipolla(a,p):
#Find a square root of a modulo p using the algorithm of Cipolla
b=0
while pow((b*b-a)%p,(p-1)/2,p)==1:
b+=1
return (GaussInt(b,1,b**2-a,p)**((p+1)/2)).x
def Base(n,b):
#Decompose n in base b
l=[]
while n:
l.append(n%b)
n/=b
return l
def InvMod(a,n):
#Find the inverse mod n of a.
#Use the Extended Euclides Algorithm.
m=[]
s=n
while n:
m.append(a/n)
(a,n)=(n,a%n)
u=1
v=0
while m:
(u,v)=(v,u-m.pop()*v)
return u%s
def b58encode(v):
#Encode a byte string to the Base58
digit="123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"
base=len(digit)
val=0
for c in v:
val*=256
val+=ord(c)
result=""
while val:
(val,mod)=divmod(val,base)
result=digit[mod]+result
pad=0
for c in v:
if c=="\0":
pad+=1
else:
break
return (digit[0]*pad)+result
def b58decode(v):
#Decode a Base58 string to byte string
digit="123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"
base=len(digit)
val=0
for c in v:
val*=base
val+=digit.find(c)
result=""
while val:
(val,mod)=divmod(val,256)
result=chr(mod)+result
pad=0
for c in v:
if c==digit[0]:
pad+=1
else:
break
result="\0"*pad+result
return result
def Byte2Hex(b):
#Convert a byte string to hex number
out=""
for x in b:
y=hex(ord(x))[2:]
if len(y)==1:
y="0"+y
out+="%2s"%y
return out
def Int2Byte(n,b):
#Convert a integer to a byte string of length b
out=""
for i in range(b):
(n,m)=divmod(n,256)
out=chr(m)+out
return out
class EllipticCurvePoint:
#Main class
#It is an point on an Elliptic Curve
def __init__(self,x,a,b,p,n=0):
#We store the coordinate in x and the elliptic curbe parameter.
#x is of length 3. This is the 3 projective coordinates of the point.
self.x=x[:]
self.a=a
self.b=b
self.p=p
self.n=n
def EqualProj(self,y):
#Does y equals self ?
#It computes self cross product with y and check if the result is 0.
return self.x[0]*y.x[1]==self.x[1]*y.x[0] and self.x[1]*y.x[2]==self.x[2]*y.x[1] and self.x[2]*y.x[0]==self.x[0]*y.x[2]
def __add__(self,y):
#The main function to add self and y
#It uses the formulas I derived in projective coordinates.
#Projectives coordinates are more performant than the usual (x,y) coordinates
#because it we don't need to compute inverse mod p, which is faster.
z=EllipticCurvePoint([0,0,0],self.a,self.b,self.p)
if self.EqualProj(y):
d=(2*self.x[1]*self.x[2])%self.p
d3=pow(d,3,self.p)
n=(3*pow(self.x[0],2,self.p)+self.a*pow(self.x[2],2,self.p))%self.p
z.x[0]=(pow(n,2,self.p)*d*self.x[2]-2*d3*self.x[0])%self.p
z.x[1]=(3*self.x[0]*n*pow(d,2,self.p)-pow(n,3,self.p)*self.x[2]-self.x[1]*d3)%self.p
z.x[2]=(self.x[2]*d3)%self.p
else:
d=(y.x[0]*self.x[2]-y.x[2]*self.x[0])%self.p
d3=pow(d,3,self.p)
n=(y.x[1]*self.x[2]-self.x[1]*y.x[2])%self.p
z.x[0]=(y.x[2]*self.x[2]*pow(n,2,self.p)*d-d3*(y.x[2]*self.x[0]+y.x[0]*self.x[2]))%self.p
z.x[1]=(pow(d,2,self.p)*n*(2*self.x[0]*y.x[2]+y.x[0]*self.x[2])-pow(n,3,self.p)*self.x[2]*y.x[2]-self.x[1]*d3*y.x[2])%self.p
z.x[2]=(self.x[2]*d3*y.x[2])%self.p
return z
def __mul__(self,n):
#The fast multiplication of point n times by itself.
b=Base(n,2)
t=EllipticCurvePoint(self.x,self.a,self.b,self.p)
b.pop()
while b:
t+=t
if b.pop():
t+=self
return t
def __repr__(self):
#print a point in (x,y) coordinate.
return "x=%d\ny=%d\n"%((self.x[0]*InvMod(self.x[2],self.p))%self.p,(self.x[1]*InvMod(self.x[2],self.p))%self.p)
def __eq__(self,x):
#Does self==x ?
return self.x==x.x and self.a==x.a and self.b==x.b and self.p==x.p
def __ne__(self,x):
#Does self!=x ?
return self.x!=x.x or self.a!=x.a or self.b!=x.b or self.p!=x.p
def Check(self):
#Is self on the curve ?
return (self.x[0]**3+self.a*self.x[0]*self.x[2]**2+self.b*self.x[2]**3-self.x[1]**2*self.x[2])%self.p==0
def GeneratePrivateKey(self):
#Generate a private key. It's just a random number between 1 and n-1.
#Of course, this function isn't cryptographically secure.
#Don't use it to generate your key. Use a cryptographically secure source of randomness instead.
#self.d = random.randint(1,self.n-1)
self.d = int(os.urandom(32).encode("hex"), 16) # Better random fix
def SignECDSA(self,m):
#Sign a message. The private key is self.d .
h=hashlib.new("SHA256")
h.update(m)
z=int(h.hexdigest(),16)
r=0
s=0
while not r or not s:
k=random.randint(1,self.n-1)
R=self*k
R.Normalize()
r=R.x[0]%self.n
s=(InvMod(k,self.n)*(z+r*self.d))%self.n
return (r,s)
def CheckECDSA(self,sig,m):
#Check a signature (r,s) of the message m using the public key self.Q
# and the generator which is self.
#This is not the one used by Bitcoin because the public key isn't known;
# only a hash of the public key is known. See the next function.
(r,s)=sig
h=hashlib.new("SHA256")
h.update(m)
z=int(h.hexdigest(),16)
if self.Q.x[2]==0:
return False
if not self.Q.Check():
return False
if (self.Q*self.n).x[2]!=0:
return False
if r<1 or r>self.n-1 or s<1 or s>self.n-1:
return False
w=InvMod(s,self.n)
u1=(z*w)%self.n
u2=(r*w)%self.n
R=self*u1+self.Q*u2
R.Normalize()
return (R.x[0]-r)%self.n==0
def VerifyMessageFromBitcoinAddress(self,adresse,m,sig):
#Check a signature (r,s) for the message m signed by the Bitcoin
# address "addresse".
h=hashlib.new("SHA256")
h.update(m)
z=int(h.hexdigest(),16)
(r,s)=sig
x=r
y2=(pow(x,3,self.p)+self.a*x+self.b)%self.p
y=Cipolla(y2,self.p)
for i in range(2):
kG=EllipticCurvePoint([x,y,1],self.a,self.b,self.p,self.n)
mzG=self*((-z)%self.n)
self.Q=(kG*s+mzG)*InvMod(r,self.n)
adr=self.BitcoinAddresFromPublicKey()
if adr==adresse:
break
y=(-y)%self.p
if adr!=adresse:
return False
return True
def BitcoinAddressFromPrivate(self,pri=None):
#Transform a private key in base58 encoding to a bitcoin address.
#normal means "uncompressed".
if not pri:
print "Private Key :",
pri=raw_input()
normal=(len(pri)==51)
pri=b58decode(pri)
if normal:
pri=pri[1:-4]
else:
pri=pri[1:-5]
self.d=int(Byte2Hex(pri),16)
return self.BitcoinAddress(normal)
def PrivateEncoding(self,normal=True):
#Encode a private key self.d to base58 encoding.
p=Int2Byte(self.d,32)
p="\80"+p
if not normal:
p+=chr(1)
h=hashlib.new("SHA256")
h.update(p)
s=h.digest()
h=hashlib.new("SHA256")
h.update(s)
s=h.digest()
cs=s[:4]
p+=cs
p=b58encode(p)
return p
def BitcoinAddresFromPublicKey(self,normal=True):
#Find the bitcoin address from the public key self.Q
#We do normalization to go from the projective coordinates to the usual
# (x,y) coordinates.
self.Q.Normalize()
if normal:
pk=chr(4)+Int2Byte(self.Q.x[0],32)+Int2Byte((self.Q.x[1])%self.p,32)
else:
if self.Q.x[1]%2==0:
pk=chr(2)+Int2Byte(self.Q.x[0],32)
else:
pk=chr(3)+Int2Byte(self.Q.x[0],32)
version=chr(0)
h=hashlib.new("SHA256")
h.update(pk)
s=h.digest()
h=hashlib.new("RIPEMD160")
h.update(s)
kh=version+h.digest()
h=hashlib.new("SHA256")
h.update(kh)
cs=h.digest()
h=hashlib.new("SHA256")
h.update(cs)
cs=h.digest()[:4]
adr=b58encode(kh+cs)
return adr
def BitcoinAddress(self,normal=True):
#Computes a bitcoin address given the private key self.d.
self.Q=self*self.d
return self.BitcoinAddresFromPublicKey(normal)
def BitcoinAddressGenerator(self,k,filename):
#Generate Bitcoin address and write them in the filename in the multibit format.
#Change the date as you like.
f=open(filename,"w")
for i in range(k):
self.GeneratePrivateKey()
adr=self.BitcoinAddress()
p=self.PrivateEncoding()
f.write("#%s\n%s 2014-01-30T12:00:00Z\n"%(adr,p))
#print hex(self.d)
print adr,p
f.close()
def TestSign(self):
#Test signature
self.GeneratePrivateKey()
self.Q=self*self.d
m="Hello World"
adresse=self.BitcoinAddresFromPublicKey()
(r,s)=self.SignECDSA(m)
m="Hello World"
print self.VerifyMessageFromBitcoinAddress(adresse,m,r,s)
def Normalize(self):
#Transform projective coordinates of self to the usual (x,y) coordinates.
if self.x[2]:
self.x[0]=(self.x[0]*InvMod(self.x[2],self.p))%self.p
self.x[1]=(self.x[1]*InvMod(self.x[2],self.p))%self.p
self.x[2]=1
elif self.x[1]:
self.x[0]=(self.x[0]*InvMod(self.x[1],self.p))%self.p
self.x[1]=1
elif self.x[0]:
self.x[0]=1
else:
raise Exception
def Bitcoin():
#Create the Bitcoin elliptiv curve
a=0
b=7
p=2**256-2**32-2**9-2**8-2**7-2**6-2**4-1
#Create the generator G of the Bitcoin elliptic curve, with is order n.
Gx=int("79BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798",16)
Gy=int("483ADA7726A3C4655DA4FBFC0E1108A8FD17B448A68554199C47D08FFB10D4B8",16)
n =int("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141",16)
#Create the generator
return EllipticCurvePoint([Gx,Gy,1],a,b,p,n)
if __name__ == "__main__":
bitcoin=Bitcoin()
#Generate the public key from the private one
print bitcoin.BitcoinAddressFromPrivate("23DKRBLkeDbcSaddsMYLAHXhanPmGwkWAhSPVGbspAkc72Hw9BdrDF")
print bitcoin.BitcoinAddress()
#Print the bitcoin address of the public key generated at the previous line
adr=bitcoin.BitcoinAddresFromPublicKey()
print adr
#Sign a message with the current address
m="Hello World"
sig=bitcoin.SignECDSA("Hello World")
#Verify the message using only the bitcoin adress, the signature and the message.
#Not using the public key as it is not needed.
print bitcoin.VerifyMessageFromBitcoinAddress(adr,m,sig)