示例#1
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文件: passive.py 项目: aalto1/crypto
 def __share_recombine(self, a):
     input_shares = shamir.share(a, self.threshold, len(self.players))
     output_shares = self._exchange_shares(input_shares)
     # Recombine the first 2t+1 output_shares.
     result = gatherShares(output_shares[:2 * self.threshold + 1])
     result.addCallback(shamir.recombine)
     return result
示例#2
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文件: passive.py 项目: aalto1/crypto
    def shamir_share(self, inputters, field, number=None, threshold=None):
        """Secret share *number* over *field* using Shamir's method.

        The number is shared using polynomial of degree *threshold*
        (defaults to :attr:`threshold`). Returns a list of shares
        unless there is only one inputter in which case the
        share is returned directly.

        In code it is used like this::

            a, b, c = runtime.shamir_share([1, 2, 3], Zp, x)

        where ``Zp`` is a field and ``x`` is a Python integer holding
        the input of each player (three inputs in total).

        If only a subset of the players provide input it looks like
        this::

            if runtime.id == 1:
                a = runtime.shamir_share([1], Zp, x)
            else:
                a = runtime.shamir_share([1], Zp)

        Instead of branching when calling :meth:`shamir_share`, one
        can give ``None`` as input::

            if runtime.id == 1:
                x = int(raw_input("Input x: "))
            else:
                x = None
            a = runtime.shamir_share([1], Zp, x)

        which might be practical in some cases.

        Communication cost: n elements transmitted.
        """
        assert number is None or self.id in inputters
        if threshold is None:
            threshold = self.threshold

        results = []
        for peer_id in inputters:
            # Unique program counter per input.
            self.increment_pc()
            if peer_id == self.id:
                shares = shamir.share(field(number), threshold,
                                      len(self.players))
                for other_id, share in shares:
                    if other_id.value == self.id:
                        results.append(Share(self, field, share))
                    else:
                        self._send_share(other_id.value, share)
            else:
                results.append(self._expect_share(peer_id, field))
        # Unpack a singleton list.
        if len(results) == 1:
            return results[0]
        else:
            return results
示例#3
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文件: passive.py 项目: MaxFangX/viff
        def share_recombine(number):
            shares = shamir.share(number, self.threshold, self.num_players)

            exchanged_shares = []
            for peer_id, share in shares:
                d = self._exchange_shares(peer_id.value, share)
                d.addCallback(lambda share, peer_id: (peer_id, share), peer_id)
                exchanged_shares.append(d)

            # Recombine the first 2t+1 shares.
            result = gather_shares(exchanged_shares[:2*self.threshold+1])
            result.addCallback(shamir.recombine)
            return result
示例#4
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文件: passive.py 项目: hanyunx/Viff
        def share_recombine(number):
            shares = shamir.share(number, self.threshold, self.num_players)

            exchanged_shares = []
            for peer_id, share in shares:
                d = self._exchange_shares(peer_id.value, share)
                d.addCallback(lambda share, peer_id: (peer_id, share), peer_id)
                exchanged_shares.append(d)

            # Recombine the first 2t+1 shares.
            result = gather_shares(exchanged_shares[:2 * self.threshold + 1])
            result.addCallback(shamir.recombine)
            return result
示例#5
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文件: test_util.py 项目: lu562/viff
 def test_shamir_share(self):
     secret = self.field(17)
     shares = shamir.share(secret, 1, 3)
     self.assertEquals(shares[0][1], secret)
     self.assertEquals(shares[1][1], secret)
     self.assertEquals(shares[2][1], secret)
示例#6
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# Shares of seller and buyer bids. Assume that each bidder and seller
# has secret shared the bids and encrypted them for each player. These
# have then been read, decrypted and summed up...

random.seed(0)

# Generate random bids -- we could generate numbers up to 2**l, but
# restricting them to only two digits use less space in the output.
B = [random.randint(1, 2**l) for _ in range(options.count)]
S = [random.randint(1, 2**l) for _ in range(options.count)]

# Make the bids monotone.
B.sort(reverse=True)
S.sort()

seller_bids = [shamir.share(Zp(x), t, n)[id - 1][1] for x in S]
buyer_bids = [shamir.share(Zp(x), t, n)[id - 1][1] for x in B]


def auction(rt):
    def debug(low, mid, high):
        string = ["  " for _ in range(high + 1)]
        string[low] = " |"
        string[mid] = " ^"
        string[high] = " |"

        print "B: " + " ".join(["%2d" % b for b in B])
        print "S: " + " ".join(["%2d" % s for s in S])
        print "   " + " ".join(["%2d" % x for x in range(len(B) + 1)])
        print "   " + " ".join(string)
示例#7
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 def test_shamir_share(self):
     secret = self.field(17)
     shares = shamir.share(secret, 1, 3)
     self.assertEquals(shares[0][1], secret)
     self.assertEquals(shares[1][1], secret)
     self.assertEquals(shares[2][1], secret)
示例#8
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# Shares of seller and buyer bids. Assume that each bidder and seller
# has secret shared the bids and encrypted them for each player. These
# have then been read, decrypted and summed up...

random.seed(0)

# Generate random bids -- we could generate numbers up to 2**l, but
# restricting them to only two digits use less space in the output.
B = [random.randint(1, 2**l) for _ in range(options.count)]
S = [random.randint(1, 2**l) for _ in range(options.count)]

# Make the bids monotone.
B.sort(reverse=True)
S.sort()

seller_bids = [shamir.share(Zp(x), t, n)[id-1][1] for x in S]
buyer_bids  = [shamir.share(Zp(x), t, n)[id-1][1] for x in B]


def auction(rt):

    def debug(low, mid, high):
        string = ["  " for _ in range(high+1)]
        string[low] = " |"
        string[mid] = " ^"
        string[high] = " |"

        print "B: " + " ".join(["%2d" % b for b in B])
        print "S: " + " ".join(["%2d" % s for s in S])
        print "   " + " ".join(["%2d" % x for x in range(len(B)+1)])
        print "   " + " ".join(string)
示例#9
0
文件: passive.py 项目: MaxFangX/viff
    def shamir_share(self, inputters, field, number=None, threshold=None):
        """Secret share *number* over *field* using Shamir's method.

        The number is shared using polynomial of degree *threshold*
        (defaults to :attr:`threshold`). Returns a list of shares
        unless there is only one inputter in which case the
        share is returned directly.

        In code it is used like this::

            a, b, c = runtime.shamir_share([1, 2, 3], Zp, x)

        where ``Zp`` is a field and ``x`` is a Python integer holding
        the input of each player (three inputs in total).

        If only a subset of the players provide input it looks like
        this::

            if runtime.id == 1:
                a = runtime.shamir_share([1], Zp, x)
            else:
                a = runtime.shamir_share([1], Zp)

        Instead of branching when calling :meth:`shamir_share`, one
        can give ``None`` as input::

            if runtime.id == 1:
                x = int(raw_input("Input x: "))
            else:
                x = None
            a = runtime.shamir_share([1], Zp, x)

        which might be practical in some cases.

        Communication cost: n elements transmitted.
        """
        assert number is None or self.id in inputters
        if threshold is None:
            threshold = self.threshold

        results = []
        for peer_id in inputters:
            # Unique program counter per input.
            self.increment_pc()

            if peer_id == self.id:
                pc = tuple(self.program_counter)
                shares = shamir.share(field(number), threshold,
                                      self.num_players)
                for other_id, share in shares:
                    if other_id.value == self.id:
                        results.append(Share(self, share.field, share))
                    else:
                        self.protocols[other_id.value].sendShare(pc, share)
            else:
                results.append(self._expect_share(peer_id, field))

        # do actual communication
        self.activate_reactor()

        # Unpack a singleton list.
        if len(results) == 1:
            return results[0]
        else:
            return results