python/bls_ZZZ.py.in

#!/usr/bin/env python3

"""
Licensed to the Apache Software Foundation (ASF) under one
or more contributor license agreements.  See the NOTICE file
distributed with this work for additional information
regarding copyright ownership.  The ASF licenses this file
to you under the Apache License, Version 2.0 (the
"License"); you may not use this file except in compliance
with the License.  You may obtain a copy of the License at

  http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing,
software distributed under the License is distributed on an
"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
KIND, either express or implied.  See the License for the
specific language governing permissions and limitations
under the License.
"""


"""
bls

This module use cffi to access the c functions in the BLS library.

There is also an example usage program in this file.

"""

import cffi
import platform
import os
ffi = cffi.FFI()
ffi.cdef("""
typedef struct {
unsigned int ira[21];  /* random number...   */
int rndptr;   /* ...array & pointer */
unsigned int borrow;
int pool_ptr;
char pool[32];    /* random pool */
} csprng;

typedef struct
{
  int len;
  int max;
  char *val;
} octet;

extern void CREATE_CSPRNG(csprng *R,octet *S);
extern void KILL_CSPRNG(csprng *R);
extern void OCT_clear(octet *O);

extern int BLS_ZZZ_KEY_PAIR_GENERATE(csprng *RNG,octet* S,octet *W);
extern int BLS_ZZZ_SIGN(octet *SIG,octet *m,octet *S);
extern int BLS_ZZZ_VERIFY(octet *SIG,octet *m,octet *W);
extern int BLS_ZZZ_ADD_G1(octet *R1,octet *R2,octet *R);
extern int BLS_ZZZ_ADD_G2(octet *W1,octet *W2,octet *W);

""")

if (platform.system() == 'Windows'):
    libamcl_bls_ZZZ = ffi.dlopen("libamcl_bls_ZZZ.dll")
    libamcl_core = ffi.dlopen("libamcl_core.dll")
elif (platform.system() == 'Darwin'):
    libamcl_bls_ZZZ = ffi.dlopen("libamcl_bls_ZZZ.dylib")
    libamcl_core = ffi.dlopen("libamcl_core.dylib")
else:
    libamcl_bls_ZZZ = ffi.dlopen("libamcl_bls_ZZZ.so")
    libamcl_core = ffi.dlopen("libamcl_core.so")

# Group Size
BGS = @NB@
# Field Size
BFS = @NB@

CURVE_SECURITY = @CS@

G1LEN = BFS + 1

if CURVE_SECURITY == 128:
    G2LEN = 4 * BFS

if CURVE_SECURITY == 192:
    G2LEN = 8 * BFS

if CURVE_SECURITY == 256:
    G2LEN = 16 * BFS


def to_str(octet_value):
    """Converts an octet type into a string

    Add all the values in an octet into an array.

    Args::

        octet_value. An octet pointer type

    Returns::

        String

    Raises:
        Exception
    """
    i = 0
    val = []
    while i < octet_value.len:
        val.append(octet_value.val[i])
        i = i + 1
    out = b''
    for x in val:
        out = out + x
    return out


def make_octet(length, value=None):
    """Generates an octet pointer

    Generates an empty octet or one filled with the input value

    Args::

        length: Length of empty octet
        value:  Data to assign to octet

    Returns::

        oct_ptr: octet pointer
        val: data associated with octet to prevent garbage collection

    Raises:

    """
    oct_ptr = ffi.new("octet*")
    if value:
        val = ffi.new("char [%s]" % len(value), value)
        oct_ptr.val = val
        oct_ptr.max = len(value)
        oct_ptr.len = len(value)
    else:
        val = ffi.new("char []", length)
        oct_ptr.val = val
        oct_ptr.max = length
        oct_ptr.len = length
    return oct_ptr, val


def create_csprng(seed):
    """Make a Cryptographically secure pseudo-random number generator instance

    Make a Cryptographically secure pseudo-random number generator instance

    Args::

        seed:   random seed value

    Returns::

        rng: Pointer to cryptographically secure pseudo-random number generator instance

    Raises:

    """
    seed_oct, seed_val = make_octet(None, seed)

    # random number generator
    rng = ffi.new('csprng*')
    libamcl_core.CREATE_CSPRNG(rng, seed_oct)
    libamcl_core.OCT_clear(seed_oct)

    return rng


def kill_csprng(rng):
    """Kill a random number generator

    Deletes all internal state

    Args::

        rng: Pointer to cryptographically secure pseudo-random number generator instance

    Returns::



    Raises:

    """
    libamcl_core.KILL_CSPRNG(rng)

    return 0


def key_pair_generate(rng, sk=None):
    """Generate key pair

    Generate key pair

    Args::

        rng: Pointer to cryptographically secure pseudo-random number generator instance
        sk: secret key. Externally generated

    Returns::

        error_code: error from the C function
        sk: secret key
        pk: public key

    Raises:

    """
    if sk:
        sk1, sk1_val = make_octet(None, sk)
        rng = ffi.NULL
    else:
        sk1, sk1val = make_octet(BGS)

    pk1, pk1val = make_octet(G2LEN)
    error_code = libamcl_bls_ZZZ.BLS_ZZZ_KEY_PAIR_GENERATE(rng, sk1, pk1)

    sk = to_str(sk1)
    pk = to_str(pk1)

    # clear memory
    libamcl_core.OCT_clear(sk1)
    libamcl_core.OCT_clear(pk1)

    return error_code, sk, pk


def sign(message, sk):
    """Calculate a signature

    Generate key pair

    Args::

        message: Message to sign
        sk: BLS secret key

    Returns::

        error_code: Zero for success or else an error code
        signature: BLS signature

    Raises:

    """
    m, m_val = make_octet(None, message)
    sk1, sk1_val = make_octet(None, sk)
    signature1, signature1_val = make_octet(G1LEN)
    error_code = libamcl_bls_ZZZ.BLS_ZZZ_SIGN(signature1, m, sk1)

    signature = to_str(signature1)

    # clear memory
    libamcl_core.OCT_clear(sk1)
    libamcl_core.OCT_clear(signature1)

    return error_code, signature


def verify(signature, message, pk):
    """Verify a signature

    Verify a signature

    Args::

        message: Message to verify
        signature: BLS signature
        pk: BLS public key

    Returns::

        error_code: Zero for success or else an error code

    Raises:

    """
    m, m_val = make_octet(None, message)
    pk1, pk1_val = make_octet(None, pk)
    signature1, signature1_val = make_octet(None, signature)
    error_code = libamcl_bls_ZZZ.BLS_ZZZ_VERIFY(signature1, m, pk1)

    # clear memory
    libamcl_core.OCT_clear(pk1)
    libamcl_core.OCT_clear(signature1)

    return error_code


def add_G1(R1, R2):
    """Add two members from the group G1

    Add two members from the group G1

    Args::

        R1:   member of G1
        R2:   member of G1

    Returns::

        R:          member of G1. R = R1+R2
        error_code: Zero for success or else an error code

    Raises:

    """
    R11, R11_val = make_octet(None, R1)
    R21, R21_val = make_octet(None, R2)
    R1, R1_val = make_octet(G1LEN)
    error_code = libamcl_bls_ZZZ.BLS_ZZZ_ADD_G1(R11, R21, R1)

    R = to_str(R1)

    # clear memory
    libamcl_core.OCT_clear(R11)
    libamcl_core.OCT_clear(R21)
    libamcl_core.OCT_clear(R1)

    return error_code, R


def add_G2(R1, R2):
    """Add two members from the group G2

    Add two members from the group G2

    Args::

        R1:   member of G2
        R2:   member of G2

    Returns::

        R:          member of G2. R = R1+R2
        error_code: Zero for success or else an error code

    Raises:

    """
    R11, R11_val = make_octet(None, R1)
    R21, R21_val = make_octet(None, R2)
    R1, R1_val = make_octet(G2LEN)
    error_code = libamcl_bls_ZZZ.BLS_ZZZ_ADD_G2(R11, R21, R1)

    R = to_str(R1)

    # clear memory
    libamcl_core.OCT_clear(R11)
    libamcl_core.OCT_clear(R21)
    libamcl_core.OCT_clear(R1)

    return error_code, R


if __name__ == "__main__":
    # Print hex values
    DEBUG = False

    # Seed
    seed_hex = "78d0fb6705ce77dee47d03eb5b9c5d30"
    seed = bytes.fromhex(seed_hex)

    # Message
    message = b"test message"

    # random number generator
    rng = create_csprng(seed)

    # Generate key pairs
    rtn, sk1, pktmp = key_pair_generate(rng)
    if rtn != 0:
        print("Error: key_pair_generate {}".format(rtn))
        raise SystemExit(0)
    print("sk1: {}".format(sk1.hex()))
    print("pktmp: {}".format(pktmp.hex()))

    rtn, sk1, pk1 = key_pair_generate(rng, sk1)
    if rtn != 0:
        print("Error: key_pair_generate {}".format(rtn))
        raise SystemExit(0)
    print("sk1: {}".format(sk1.hex()))
    print("pk1: {}".format(pk1.hex()))

    rtn, sk2, pk2 = key_pair_generate(rng)
    if rtn != 0:
        print("Error: key_pair_generate {}".format(rtn))
        raise SystemExit(0)
    print("sk2: {}".format(sk2.hex()))
    print("pk2: {}".format(pk2.hex()))

    rtn, sk3, pk3 = key_pair_generate(rng)
    if rtn != 0:
        print("Error: key_pair_generate {}".format(rtn))
        raise SystemExit(0)
    print("sk3: {}".format(sk3.hex()))
    print("pk3: {}".format(pk3.hex()))

    # Sign and verify
    rtn, sig1 = sign(message, sk1)
    if rtn != 0:
        print("Error: sign {}".format(rtn))
        raise SystemExit(0)
    print("sig1: {}".format(sig1.hex()))

    rtn = verify(sig1, message, pk1)
    if rtn != 0:
        print("Error: Invalid signature {}".format(rtn))
        raise SystemExit(0)
    print("Success: Signature is valid")

    rtn, sig2 = sign(message, sk2)
    if rtn != 0:
        print("Error: sign {}".format(rtn))
        raise SystemExit(0)
    print("sig2: {}".format(sig2.hex()))

    rtn = verify(sig2, message, pk2)
    if rtn != 0:
        print("Error: Invalid signature {}".format(rtn))
        raise SystemExit(0)
    print("Success: Signature is valid")

    rtn, sig3 = sign(message, sk3)
    if rtn != 0:
        print("Error: sign {}".format(rtn))
        raise SystemExit(0)
    print("sig3: {}".format(sig3.hex()))

    rtn = verify(sig3, message, pk3)
    if rtn != 0:
        print("Error: Invalid signature {}".format(rtn))
        raise SystemExit(0)
    print("Success: Signature is valid")

    # Add Signatures
    rtn, sig12 = add_G1(sig1, sig2)
    if rtn != 0:
        print("Error: add_G1 {}".format(rtn))
        raise SystemExit(0)
    print("sig12: {}".format(sig12.hex()))

    rtn, sig123 = add_G1(sig12, sig3)
    if rtn != 0:
        print("Error: add_G1 {}".format(rtn))
        raise SystemExit(0)
    print("sig123: {}".format(sig123.hex()))

    # Add Public keys
    rtn, pk12 = add_G2(pk1, pk2)
    if rtn != 0:
        print("Error: add_G2 {}".format(rtn))
        raise SystemExit(0)
    print("pk12: {}".format(pk12.hex()))

    rtn, pk123 = add_G2(pk12, pk3)
    if rtn != 0:
        print("Error: add_G2 {}".format(rtn))
        raise SystemExit(0)
    print("pk123: {}".format(pk123.hex()))

    # Verify aggretated values
    rtn = verify(sig123, message, pk123)
    if rtn != 0:
        print("Error: Invalid aggregated signature {}".format(rtn))
        raise SystemExit(0)
    print("Success: Aggregated signature is valid")

    # Clear memory
    kill_csprng(rng)
    del sk1
    del pk1
    del sk2
    del pk2
    del sk3
    del pk3