Sellar un archivo para que nadie pueda discutir que no lo tocaste
Una discusión sobre un archivo digital casi nunca se pierde por lo que el archivo dice. Se pierde una pregunta antes: ¿Cómo sabemos que ese es el archivo que usted recibió, y no el que editó anoche? Si la respuesta es "confíe en mí", ya perdiste. Y da igual cuánta razón tengas en el fondo. Este problema no es exclusivo de un juzgado. Lo tiene el auditor que recibe un volcado de logs, el equipo…
To prevent any accusations that a digital file has been tampered with, a tool named Tunjo has been developed. This tool works with read-only material, calculates a hash, and signs an acta that can be verified by anyone. The reason for using a Merkle tree instead of a single hash is to avoid exposing unnecessary material or relying on an unverified reconstruction.
The Merkle tree structure separates the domain by not allowing a leaf to appear as an internal node, ensuring the hash of a leaf cannot be presented as a node in the tree. Additionally, the tree includes the number of leaves, preventing ambiguity in trees with an odd number of leaves. The hash covers the state of the file, not just its content, which is essential as moving a file between folders, renaming it, or replacing it with a link to the same content would change its meaning.
The signing process uses a triple-hybrid signature of Quipu: Ed25519, ML-DSA-87 (FIPS 204), and SLH-DSA-SHA2-256s (FIPS 205), all of which must validate. This ensures the seal remains valid even after many years. Each element in the collection, including its content, size, date, state, and hash, must be included in the hash to accurately represent its meaning. A verified signature is required because a signature alone cannot guarantee the integrity of the data.
When verifying a file's integrity, it is crucial to recalculate the tree and then check the signature. A verified signature alone is not enough, as someone with the private key could generate a new acta with a different hash. The tool should also handle unreadable files explicitly, recording them as errors in the acta. The timestamp should be declared, indicating whether the verification is relative or based on a specific date.
Symbolic links should not be followed, and their destination should be recorded. The tool should not attempt to detect intrusions or attribute authorship, as these are beyond its scope. Lastly, the tool does not conclude the verification process, leaving it to the user to interpret the results.
Written by urgent.news from Dev.to's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
