sam.hadow/tea3-py
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

linear and differential bias change

Browse Source
This commit is contained in:
Sam Hadow
2026-05-11 10:36:32 +02:00
parent 0f13b2fbfb
commit 3f2f45c47b
3 changed files with 57 additions and 31 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/tea3/constants.py
+19
View File
@@ -17,6 +17,25 @@ TEA3_SBOX = [
0x52, 0x8C, 0x5D, 0x29, 0x6D, 0x04, 0xBC, 0x25, 0x15, 0x8B, 0x12, 0x9B, 0xD6, 0x75, 0xA3, 0x97,
]
AES_SBOX = [
0x63, 0x7C, 0x77, 0x7B, 0xF2, 0x6B, 0x6F, 0xC5, 0x30, 0x01, 0x67, 0x2B, 0xFE, 0xD7, 0xAB, 0x76,
0xCA, 0x82, 0xC9, 0x7D, 0xFA, 0x59, 0x47, 0xF0, 0xAD, 0xD4, 0xA2, 0xAF, 0x9C, 0xA4, 0x72, 0xC0,
0xB7, 0xFD, 0x93, 0x26, 0x36, 0x3F, 0xF7, 0xCC, 0x34, 0xA5, 0xE5, 0xF1, 0x71, 0xD8, 0x31, 0x15,
0x04, 0xC7, 0x23, 0xC3, 0x18, 0x96, 0x05, 0x9A, 0x07, 0x12, 0x80, 0xE2, 0xEB, 0x27, 0xB2, 0x75,
0x09, 0x83, 0x2C, 0x1A, 0x1B, 0x6E, 0x5A, 0xA0, 0x52, 0x3B, 0xD6, 0xB3, 0x29, 0xE3, 0x2F, 0x84,
0x53, 0xD1, 0x00, 0xED, 0x20, 0xFC, 0xB1, 0x5B, 0x6A, 0xCB, 0xBE, 0x39, 0x4A, 0x4C, 0x58, 0xCF,
0xD0, 0xEF, 0xAA, 0xFB, 0x43, 0x4D, 0x33, 0x85, 0x45, 0xF9, 0x02, 0x7F, 0x50, 0x3C, 0x9F, 0xA8,
0x51, 0xA3, 0x40, 0x8F, 0x92, 0x9D, 0x38, 0xF5, 0xBC, 0xB6, 0xDA, 0x21, 0x10, 0xFF, 0xF3, 0xD2,
0xCD, 0x0C, 0x13, 0xEC, 0x5F, 0x97, 0x44, 0x17, 0xC4, 0xA7, 0x7E, 0x3D, 0x64, 0x5D, 0x19, 0x73,
0x60, 0x81, 0x4F, 0xDC, 0x22, 0x2A, 0x90, 0x88, 0x46, 0xEE, 0xB8, 0x14, 0xDE, 0x5E, 0x0B, 0xDB,
0xE0, 0x32, 0x3A, 0x0A, 0x49, 0x06, 0x24, 0x5C, 0xC2, 0xD3, 0xAC, 0x62, 0x91, 0x95, 0xE4, 0x79,
0xE7, 0xC8, 0x37, 0x6D, 0x8D, 0xD5, 0x4E, 0xA9, 0x6C, 0x56, 0xF4, 0xEA, 0x65, 0x7A, 0xAE, 0x08,
0xBA, 0x78, 0x25, 0x2E, 0x1C, 0xA6, 0xB4, 0xC6, 0xE8, 0xDD, 0x74, 0x1F, 0x4B, 0xBD, 0x8B, 0x8A,
0x70, 0x3E, 0xB5, 0x66, 0x48, 0x03, 0xF6, 0x0E, 0x61, 0x35, 0x57, 0xB9, 0x86, 0xC1, 0x1D, 0x9E,
0xE1, 0xF8, 0x98, 0x11, 0x69, 0xD9, 0x8E, 0x94, 0x9B, 0x1E, 0x87, 0xE9, 0xCE, 0x55, 0x28, 0xDF,
0x8C, 0xA1, 0x89, 0x0D, 0xBF, 0xE6, 0x42, 0x68, 0x41, 0x99, 0x2D, 0x0F, 0xB0, 0x54, 0xBB, 0x16,
]
TEA3_LUT_A = [
0x92A7, 0xA761, 0x974C, 0x6B8C, 0x29CE, 0x176C, 0x39D4, 0x7463
]
src/tea3/tea3differentialbias.py
+19 -25
View File
@@ -10,17 +10,12 @@ def rand_key(rng: Random) -> list[int]:
return [rng.getrandbits(8) for _ in range(10)]
def xor_key_with_delta(key: list[int], delta: bytes | list[int], offset: int = 0) -> list[int]:
"""
XOR a delta into a key starting at offset.
"""
out = list(key)
for i, d in enumerate(delta):
j = offset + i
if j >= len(out):
break
out[j] ^= d & 0xFF
return out
def rand_frame_number(rng: Random) -> int:
return rng.getrandbits(32)
def xor_frame_with_delta(frame_number: int, delta: int) -> int:
return (frame_number ^ delta) & 0xFFFFFFFF
@dataclass
@@ -34,9 +29,8 @@ class DiffBiasResult:
def estimate_black_box_differential_bias(
*,
frame_number: int,
key_delta: bytes | list[int],
key_delta_offset: int = 0,
key: list[int],
frame_number_delta: int,
output_byte_index: int = 0,
target_diff: int = 0x00,
samples: int = 10000,
@@ -47,11 +41,11 @@ def estimate_black_box_differential_bias(
target_diff &= 0xFF
for _ in range(samples):
key1 = rand_key(rng)
key2 = xor_key_with_delta(key1, key_delta, key_delta_offset)
frame1 = rand_frame_number(rng)
frame2 = xor_frame_with_delta(frame1, frame_number_delta)
tea1 = Tea3(frame_number, key1)
tea2 = Tea3(frame_number, key2)
tea1 = Tea3(frame1, key)
tea2 = Tea3(frame2, key)
out1 = 0
out2 = 0
@@ -66,7 +60,6 @@ def estimate_black_box_differential_bias(
p_match = matches / samples
random_baseline = 1.0 / 256.0
bias = abs(p_match - random_baseline)
needed = float("inf") if bias == 0 else 1.0 / (bias * bias)
return DiffBiasResult(
@@ -79,19 +72,20 @@ def estimate_black_box_differential_bias(
def main() -> None:
frame = 0x12345678
rng = Random(123)
key = rand_key(rng)
key_delta = [0x01]
frame_number_delta = 0x00000001
res = estimate_black_box_differential_bias(
frame_number=frame,
key_delta=key_delta,
key_delta_offset=0,
key=key,
frame_number_delta=frame_number_delta,
output_byte_index=0,
target_diff=0x00,
samples=20000,
seed=123,
)
print("black-box differential bias")
print("expected non-biased p_match: 1/256 = 0.00390625") # 256 possibilities for 1 Byte
print("expected non-biased p_match: 1/256 = 0.00390625")
print(res)
src/tea3/tea3linearbias.py
+19 -6
View File
@@ -5,9 +5,15 @@ from random import Random
from .tea3 import Tea3
def rand_key(rng: Random) -> list[int]:
return [rng.getrandbits(8) for _ in range(10)]
def rand_frame_number(rng: Random) -> int:
return rng.getrandbits(32)
@dataclass
class BiasResult:
samples: int
@@ -16,9 +22,10 @@ class BiasResult:
bias: float
estimated_needed_samples: float
def estimate_black_box_output_bias(
*,
frame_number: int,
key: list[int],
output_byte_index: int = 0,
output_bit: int = 0,
samples: int = 10000,
@@ -28,12 +35,12 @@ def estimate_black_box_output_bias(
matches = 0
for _ in range(samples):
key = rand_key(rng)
frame_number = rand_frame_number(rng)
tea = Tea3(frame_number, key)
out_byte = 0
for _ in range(output_byte_index + 1):
tea.next_byte()
out_byte = tea.iv_view() >> 56
bit = (out_byte >> output_bit) & 1
@@ -52,16 +59,22 @@ def estimate_black_box_output_bias(
estimated_needed_samples=needed,
)
def main():
frame = 0x12345678
rng = Random(123)
key = rand_key(rng)
res = estimate_black_box_output_bias(
frame_number=frame,
key=key,
output_byte_index=0,
output_bit=0,
samples=20000,
seed=123,
)
print("black-box output bias")
print("expected non-biased p_match: 1/2") # 2 possibilities for 1 bit
print("expected non-biased p_match: 1/2")
print(res)
if __name__ == "__main__":
main()