mirror of
https://github.com/trezor/trezor-firmware.git
synced 2024-12-30 01:58:11 +00:00
35 lines
705 B
Python
35 lines
705 B
Python
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import sys
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seed = 0
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def random_buffer(length: int) -> bytes:
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length = length
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if length % 4 != 0:
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raise ValueError("Use only for whole words (multiples of 4 bytes)")
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b = bytearray(length)
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for i in range(length):
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if i % 4 == 0:
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rand = random32().to_bytes(4, sys.byteorder)
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b[i] = rand[i % 4]
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return bytes(b)
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def random_reseed(reseed: int = 0):
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global seed
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seed = reseed
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def random32():
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global seed
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seed = (1664525 * seed + 1013904223) & 0xFFFFFFFF
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return seed
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def random_uniform(n: int):
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max = 0xFFFFFFFF - (0xFFFFFFFF % n)
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while True:
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x = random32()
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if x < max:
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return x // (max // n)
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