Fuzz-Based Path Integrity

The problem

It is difficult to ensure that data remains accurate and consistent as it moves through a complex sequence of steps. Small unauthorized changes or errors can corrupt the entire path.

What it does

It checks a sequence of data steps by comparing the actual path against a set of expected changes while intentionally testing for errors. It flags any unauthorized changes or inconsistencies in the data flow.

Why it matters

It ensures that data remains reliable and untampered with as it moves through a system.

Validation

It was run in the sandbox and it failed. run output shows an error/traceback — the artifact does NOT run clean.

$ python3 fuzz_path_integrity_validator.py
Traceback (most recent call last):
  File "/work/fuzz_path_integrity_validator.py", line 41, in <module>
    states = create_hash_chain(states)
             ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/work/fuzz_path_integrity_validator.py", line 8, in create_hash_chain
    prev_hash = states[i]['path_metric'].encode()
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'int' object has no attribute 'encode'

No screenshot — there is nothing working to show. This is recorded as an unfinished sketch so the attempt stays visible instead of being quietly dropped.

The code

All of it — 52 lines, one file, standard library only.

import hashlib
import random


def create_hash_chain(states):
    for i in range(len(states)):
        if i == 0:
            prev_hash = states[i]['path_metric'].encode()
        else:
            prev_hash = states[i-1]['hash']
        current_data = states[i]['path_metric'].encode()
        combined = prev_hash + current_data
        states[i]['hash'] = hashlib.sha256(combined).hexdigest()
    return states

def inject_noise(states, probability=0.3):
    for i in range(1, len(states)):
        if random.random() < probability:
            states[i]['path_metric'] += random.randint(1, 50)
    return states

def validate_path(states):
    valid = True
    for i in range(len(states)):
        if i == 0:
            expected_hash = hashlib.sha256(str(states[i]['path_metric']).encode()).hexdigest()
        else:
            prev_hash = states[i-1]['hash']
            current_data = str(states[i]['path_metric']).encode()
        combined = prev_hash + current_data
        expected_hash = hashlib.sha256(combined).hexdigest()
        if expected_hash != states[i]['hash']:
            print(f"State {i} invalid. Expected {expected_hash}, got {states[i]['hash']}")
            valid = False
            break
    return valid

if __name__ == "__main__":
    # Create initial hash chain
    states = [{'path_metric': 100} for _ in range(10)]
    states = create_hash_chain(states)
    
    # Inject noise (unauthorized modifications)
    noisy_states = inject_noise(states)
    
    # Validate the noisy states
    is_valid = validate_path(noisy_states)
    
    if is_valid:
        print("Path integrity validated. No unauthorized modifications detected.")
    else:
        print("Path integrity check failed. Unauthorized modifications detected.")