research-lab/source-code/MiniNero/RingCT.py
2016-02-05 13:20:44 -07:00

123 lines
4.2 KiB
Python

import MiniNero
import MLSAG
import LLW_Sigs
import PaperWallet
import AggregateSchnorr
import Ecdh
import Translator
def getHForCT():
return "8b655970153799af2aeadc9ff1add0ea6c7251d54154cfa92c173a0dd39c1f94"
A = MiniNero.publicFromInt(1)
H = MiniNero.hashToPoint_ct(A)
Translator.hexToC(H)
print(H)
return H
def getH2ForCT():
A = MiniNero.publicFromInt(1)
HPow2 = MiniNero.hashToPoint_ct(A)
two = MiniNero.intToHex(2)
H2 = [None] * 64
for i in range(0, 64):
Translator.hexToCComma(HPow2)
H2[i] = HPow2
HPow2 = MiniNero.scalarmultKey(HPow2, two)
return H2
def binary(n, digits):
b = [0] * digits
i = 0
while n:
b[i] = n & 1
i = i + 1
n >>= 1
return b
#unused? (Maybe I was just using for testing..)
def dec(binArray):
s = 0
i = 0
for a in binArray:
s = s + a * 2 ** i
i+= 1
return s
def sumCi(Cis):
CSum = MiniNero.identity()
for i in Cis:
CSum = MiniNero.addKeys(CSum, i)
return CSum
def sumCiExp(Cis, Exp):
#Cis is a vector
#Exp is a vector
CSum = MiniNero.identity()
for i in range(0, len(Cis)):
CSum = MiniNero.addKeys(CSum, MiniNero.scalarmultKey(Cis[i], MiniNero.intToHex(10 ** Exp[i])))
return CSum
def genRangeProof(b, digits):
bb = binary(b, digits) #gives binary form of bb in "digits" binary digits
print("b, b in binary", b, bb)
ai = [None] * len(bb)
Ci = [None] * len(bb)
CiH = [None] * len(bb) #this is like Ci - 2^i H
a = MiniNero.intToHex(0)
ii = [None] * len(bb)
indi = [None] * len(bb)
for i in range(0, len(bb)):
ai[i] = PaperWallet.skGen()
a = MiniNero.addScalars(a, ai[i]) #creating the total mask since you have to pass this to receiver...
Ci[i] = MiniNero.addKeys(MiniNero.scalarmultBase(ai[i]), MiniNero.scalarmultKey(getHForCT(), MiniNero.intToHex(bb[i] * 2 ** i)))
CiH[i] = MiniNero.subKeys(Ci[i], MiniNero.scalarmultKey(getHForCT(), MiniNero.intToHex(2 ** i)))
L1, s2, s = AggregateSchnorr.GenASNL(ai, Ci, CiH, bb)
return sumCi(Ci), Ci, L1, s2, s, a
def verRangeProof(Ci, L1, s2, s):
n = len(Ci) #note there will be some fixed length eventually so you can't just get the top digit
CiH = [None] * n
for i in range(0, n):
CiH[i] = MiniNero.subKeys(Ci[i], MiniNero.scalarmultKey(getHForCT(), MiniNero.intToHex(2 ** i)))
return AggregateSchnorr.VerASNL(Ci, CiH, L1, s2, s)
def ComputeReceivedAmount(senderEphemPk, receiverSK, maskedMask, maskedAmount, Ci, exponent):
ss1, ss2 = ecdh.ecdhretrieve(receiverSK, senderEphemPk)
mask = MiniNero.sc_sub_keys(maskedMask, ss1)
CSum = sumCi(Ci)
bH = MiniNero.subKeys(CSum, MiniNero.scalarmultBase(mask)) #bH = C - aG
b = MiniNero.sc_sub_keys(maskedAmount, ss2)
print("received amount:", 10 ** exponent * MiniNero.hexToInt(b))
H = getHForCT()
bHTent = MiniNero.scalarmultKey(H, b)
print(bHTent,"=?", bH)
if bHTent != bH:
print("wrong amount sent!")
return -1
return 0
def genRCTSig(sk_x, sk_in, sk_out, Pk, CIn, COut, ExpIn, ExpOut, index):
#sk_x is private keys of addresses (vector)
#sk_in is masks of input commitments (vector)
#sk_out is masks of output commitments (vector)
#Pk is public key list (2d array)
#CIn is input commitments (2d array)
#COut is output commitments (vector)
#ExpIn is exponents for the input commitments (2d array)
#so each row of this is going to correspond to a column in the actual mlsag..
#ExpOut is exponents for the output commitments
#index is the secret index
sk = sk_x[:]
sk.append(MiniNero.sc_sub_keys(MiniNero.sc_add(sk_in, ExpIn[index]), MiniNero.sc_add(sk_out, ExpOut)))
CRow = [None] * len(CIn) #commitments row of public keys Cin - Cout
COutSum = sumCiExp(COut, ExpOut) #Cout1*10^i_1 + Cout2 * 10^{i_2}..
tmp = MiniNero.identity()
pk = [None] * (len(sk_x) + 1) #generalize later...
pk[0] = Pk
for i in range(0, len(CIn)):
CRow[i] = MiniNero.subKeys(sumCiExp(CIn[i], ExpIn[i]), COutSum)
pk[1] = CRow
II, cc, ssVal = MLSAG.MLSAG_Sign(pk, sk, index)
return pk, II, cc, ssVal