sha256.py Numba njit implementation

sha256.py

"""This Python module is an implementation of the SHA-256 algorithm.
From https://github.com/keanemind/Python-SHA-256"""

'''
MIT License

Copyright (c) 2018 Keane Nguyen

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
'''

'''
Pure Numba njit implementation: ysdede
'''

# import logging
# numba_logger = logging.getLogger('numba')
# numba_logger.setLevel(logging.WARNING)




import numba
@numba.njit(fastmath=True)
def generate_hash(message_block):

    K = [
        0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
        0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
        0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
        0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
        0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
        0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
        0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
        0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
    ]

    # Prepare message schedule
    message_schedule = []
    mss_int = []

    for t in range(64):
        if t <= 15:
            # adds the t'th 32 bit word of the block,
            # starting from leftmost word
            # 4 bytes at a time
            # message_schedule.append(bytes(message_block[t * 4:(t * 4) + 4]))

            message_schedule.append(message_block[t * 4:(t * 4) + 4])

            dmmy = 0
            for nbytes in message_schedule[t]:
                dmmy <<= 8
                dmmy += nbytes
            mss_int.append(dmmy)

        else:

            num1 = mss_int[t - 2]
            n1a = num1
            n1a = (n1a >> 17) | (n1a << 32 - 17)
            n1b = num1
            n1b = (n1b >> 19) | (n1b << 32 - 19)

            term1 = (n1a ^ n1b ^ (num1 >> 10))

            term2 = mss_int[t - 7]
            num3 = mss_int[t - 15]

            n3a = num3
            n3b = num3
            n3a = (n3a >> 7) | (n3a << 32 - 7)
            n3b = (n3b >> 18) | (n3b << 32 - 18)

            term3 = (n3a ^ n3b ^ (num3 >> 3))

            term4 = mss_int[t - 16]

            sch_int = ((term1 + term2 + term3 + term4) % 2**32)

            mss_int.append(sch_int)

    assert len(mss_int) == 64

    # Setting Initial Hash Value
    h0 = 0x6a09e667
    h1 = 0xbb67ae85
    h2 = 0x3c6ef372
    h3 = 0xa54ff53a
    h5 = 0x9b05688c
    h4 = 0x510e527f
    h6 = 0x1f83d9ab
    h7 = 0x5be0cd19

    # Initialize working variables
    a = h0
    b = h1
    c = h2
    d = h3
    e = h4
    f = h5
    g = h6
    h = h7

    # Iterate for t=0 to 63
    for t in range(64):
        ea = e
        ea = (ea >> 6) | (ea << 32 - 6)
        eb = e
        eb = (eb >> 11) | (eb << 32 - 11)
        ec = e
        ec = (ec >> 25) | (ec << 32 - 25)

        cs1 = (ea ^ eb ^ ec)
        ch = (e & f) ^ ((~e) & g)

        t_int = mss_int[t]

        t1 = ((h + cs1 + ch + K[t] + t_int) % 2**32)

        aa = a
        ab = a
        ac = a
        aa = (aa >> 2) | (aa << 32 - 2)
        ab = (ab >> 13) | (ab << 32 - 13)
        ac = (ac >> 22) | (ac << 32 - 22)

        cs0 = (aa ^ ab ^ ac)
        maj = (a & b) ^ (a & c) ^ (b & c)
        t2 = (cs0 + maj) % 2**32

        h = g
        g = f
        f = e
        e = (d + t1) % 2**32
        d = c
        c = b
        b = a
        a = (t1 + t2) % 2**32

    # Compute intermediate hash value
    h0 = (h0 + a) % 2**32
    h1 = (h1 + b) % 2**32
    h2 = (h2 + c) % 2**32
    h3 = (h3 + d) % 2**32
    h4 = (h4 + e) % 2**32
    h5 = (h5 + f) % 2**32
    h6 = (h6 + g) % 2**32
    h7 = (h7 + h) % 2**32

    return [h0, h1, h2, h3, h4, h5, h6, h7]


if __name__ == "__main__":
    print(generate_hash("Hello").hex())