Google DeepMind melds humans and AI agents to vet Signal's secure messaging techniques
Google DeepMind researchers have completed a formal verification of Signal's messaging security, marking what they claim is the first time AI has helped devise a proof that links protocol-level security guarantees to a widely used cryptographic implementation.
Key points
- DeepMind researchers were able to formally verify that the widely used encryption protocol works as intended.
- In so doing, the Google/DeepMind team – Swarat Chaudhuri, Andrew Ferraiuolo, Anton Kovsharov, Tej Chajed, Sam Schlesinger, Karn Seth, Jonathan Katz, Charles Sutton, and Pushmeet Kohli – has taken a step toward a challenge the Beneficial AI Foundation issued in April to formally verify the Signal protocol and Signal app with Lean.
- That's going to be super important, but we have to figure that out." Pointing to a related DeepMind project, AlphaProof Nexus, which is focused on mathematics, Chaudhuri said the next step is to apply this technology during the software design process – not just to cryptographic protocols but code in general.
"It's a system that is fundamentally built for human AI collaboration," said Swarat Chaudhuri, research scientist at Google DeepMind and a professor at the University of Texas at Austin, in an interview with The Register.
Additional details
- Based on this spec, the researchers assigned Gemini Carbon agents to generate Lean code proving the correctness of the libsignal implementation.
- After the agents generated 6.5 million lines of Lean code, they undertook an auditing pass and flagged bits that required human review.
- AlphaProof Code relies on a human-guided agent that writes a Lean specification, assesses machine code semantics, and crafts an agent-authored proof that the Lean kernel checks against the specification.
- In this instance, AlphaProof Code verified Signal’s post-quantum PQXDH handshake and Triple Ratchet, thereby validating the design of libsignal 's forward secrecy, authentication, post-compromise security, and handshake secrecy.
- AlphaProof Code, they believe, can drastically reduce the cost of formal verification, though their Signal work still took four weeks for a team of five people and "quite a few tokens." "The dream is definitely to scale this up," said Chaudhuri.
How this summary was made: extractive summary — built from the sources' own reporting. It is drawn only from the reporting of the sources listed below — read the originals for full detail. How we summarize →
Advertisement
Every article behind this summary — 2 articles from 2 outlets
Get stories like this in your inbox.
Subscribe — it's freeOne free email at 6am — your topics, deduplicated, five minutes. No account, no paywall.