Initial version

Kind of slow, but works.

.gitignore

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+__pycache__
+*.egg-info

examples/test_mux.py

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+import numpy
+import time
+
+from tfhe import *
+
+
+def int_to_bitarray(x):
+    return numpy.array([((x >> i) & 1 != 0) for i in range(16)])
+
+
+def bitarray_to_int(x):
+    int_answer = 0
+    for i in range(16):
+        int_answer = int_answer | (x[i] << i)
+    return int_answer
+
+
+def reference_mux(bits1, bits2, bits3):
+    numpy.array([b if a else c for a, b, c in zip(bits1, bits2, bits3)])
+
+
+def encrypt():
+
+    rng = numpy.random.RandomState(123)
+
+    print("Key generation:")
+    t = time.time()
+    secret_key, cloud_key = tfhe_key_pair(rng)
+    print(time.time() - t)
+
+    bits1 = int_to_bitarray(2017)
+    bits2 = int_to_bitarray(42)
+    bits3 = int_to_bitarray(12345)
+
+    print("Encryption:")
+    t = time.time()
+    ciphertext1 = tfhe_encrypt(rng, secret_key, bits1)
+    ciphertext2 = tfhe_encrypt(rng, secret_key, bits2)
+    ciphertext3 = tfhe_encrypt(rng, secret_key, bits3)
+    print(time.time() - t)
+
+    return secret_key, cloud_key, ciphertext1, ciphertext2, ciphertext3
+
+
+def process(cloud_key, ciphertext1, ciphertext2, ciphertext3):
+    params = tfhe_parameters(cloud_key)
+    result = empty_ciphertext(params, ciphertext1.shape)
+
+    print("Processing:")
+    t = time.time()
+    tfhe_gate_MUX_(cloud_key, result, ciphertext1, ciphertext2, ciphertext3)
+    print(time.time() - t)
+
+    return result
+
+
+def verify(secret_key, answer):
+    print("Decryption:")
+    t = time.time()
+    answer_bits = tfhe_decrypt(secret_key, answer)
+    print(time.time() - t)
+
+    int_answer = bitarray_to_int(answer_bits)
+    print("Answer:", int_answer)
+
+
+secret_key, cloud_key, ciphertext1, ciphertext2, ciphertext3 = encrypt()
+answer = process(cloud_key, ciphertext1, ciphertext2, ciphertext3)
+verify(secret_key, answer)

examples/tutorial.py

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+import numpy
+import time
+
+from tfhe import *
+
+
+def int_to_bitarray(x):
+    return numpy.array([((x >> i) & 1 != 0) for i in range(16)])
+
+
+def bitarray_to_int(x):
+    int_answer = 0
+    for i in range(16):
+        int_answer = int_answer | (x[i] << i)
+    return int_answer
+
+
+def reference_mux(bits1, bits2, bits3):
+    numpy.array([b if a else c for a, b, c in zip(bits1, bits2, bits3)])
+
+
+def encrypt():
+
+    rng = numpy.random.RandomState(123)
+
+    secret_key, cloud_key = tfhe_key_pair(rng)
+
+    bits1 = int_to_bitarray(2017)
+    bits2 = int_to_bitarray(42)
+
+    ciphertext1 = tfhe_encrypt(rng, secret_key, bits1)
+    ciphertext2 = tfhe_encrypt(rng, secret_key, bits2)
+
+    return secret_key, cloud_key, ciphertext1, ciphertext2
+
+
+# elementary full comparator gate that is used to compare the i-th bit:
+#   input: ai and bi the i-th bit of a and b
+#          lsb_carry: the result of the comparison on the lowest bits
+#   algo: if (a==b) return lsb_carry else return b
+def encrypted_compare_bit_(cloud_key, result, a, b, lsb_carry, tmp):
+    tfhe_gate_XNOR_(cloud_key, tmp, a, b)
+    tfhe_gate_MUX_(cloud_key, result, tmp, lsb_carry, a)
+
+
+# this function compares two multibit words, and puts the max in result
+def encrypted_minimum_(cloud_key, result, a, b):
+
+    nb_bits = result.shape[0]
+
+    params = tfhe_parameters(cloud_key)
+
+    tmp1 = empty_ciphertext(params, (1,))
+    tmp2 = empty_ciphertext(params, (1,))
+
+    # initialize the carry to 0
+    tfhe_gate_CONSTANT_(cloud_key, tmp1, False)
+
+    # run the elementary comparator gate n times
+    for i in range(nb_bits):
+        encrypted_compare_bit_(cloud_key, tmp1, a[i:i+1], b[i:i+1], tmp1, tmp2)
+
+    # tmp1 is the result of the comparaison: 0 if a is larger, 1 if b is larger
+    # select the max and copy it to the result
+    tfhe_gate_MUX_(cloud_key, result, tmp1, b, a)
+
+
+
+def process(cloud_key, ciphertext1, ciphertext2):
+
+    # if necessary, the params are inside the key
+    params = tfhe_parameters(cloud_key)
+
+    # do some operations on the ciphertexts: here, we will compute the
+    # minimum of the two
+    result = empty_ciphertext(params, ciphertext1.shape)
+    encrypted_minimum_(cloud_key, result, ciphertext1, ciphertext2)
+
+    return result
+
+
+def verify(secret_key, answer):
+    answer_bits = tfhe_decrypt(secret_key, answer)
+    int_answer = bitarray_to_int(answer_bits)
+    print("Answer:", int_answer)
+
+
+secret_key, cloud_key, ciphertext1, ciphertext2 = encrypt()
+answer = process(cloud_key, ciphertext1, ciphertext2)
+verify(secret_key, answer)

setup.py

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+from setuptools import setup
+
+setup(
+    name='tfhe',
+    version='0.0.1',
+    description='TFHE port in Python',
+    url='http://github.com/nucypher/tfhe.py',
+    author='Bogdan Opanchuk',
+    author_email='bogdan@nucypher.com',
+    license='MIT',
+    packages=['tfhe'],
+    install_requires=['numpy'],
+    zip_safe=True)

tfhe/__init__.py

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+from .keys import (
+    tfhe_key_pair,
+    tfhe_parameters,
+    tfhe_encrypt,
+    tfhe_decrypt,
+    empty_ciphertext
+    )
+
+from .boot_gates import tfhe_gate_MUX_, tfhe_gate_CONSTANT_, tfhe_gate_XNOR_