Verus is a Rust verification framework designed for low-level systems programming. It extends Rust with features like specifications (preconditions, postconditions, and invariants) and data-race freedom proofs, allowing developers to formally verify the correctness and safety of their code. Verus integrates with existing Rust tools and aims to be practical for real-world systems development, leveraging SMT solvers to automate the verification process. It specifically targets areas like cryptography, operating systems kernels, and concurrent data structures, where rigorous correctness is paramount.
A distributed computing project leveraging idle CPU time from volunteers' computers has set a new verification record for the Goldbach Conjecture. The project, utilizing a novel grid computing approach, has confirmed the conjecture – which states that every even number greater than 2 can be expressed as the sum of two primes – up to 4 * 10^18 + 7 * 10^13. This surpasses previous verification efforts by a significant margin and demonstrates the potential of harnessing distributed computing power for tackling complex mathematical problems.
Hacker News users discuss the computational resources used for the Goldbach conjecture verification, questioning the value and novelty of the achievement. Some commenters express skepticism about the significance of extending the verification limit, arguing that it doesn't contribute significantly to proving the conjecture itself. Others point out the inefficiency of the distributed grid computing approach compared to more optimized single-machine implementations. A few users discuss the specific hardware and software used in the project, including the use of BOINC and GPUs, while others debate the proper way to credit contributors in such distributed projects. Several commenters express concern about the lack of available source code and details on the verification methodology, hindering independent verification and analysis.
Jonathan Protzenko announced the release of Evercrypt 1.0 for Python, providing a high-assurance cryptography library with over 15,000 lines of formally verified code. This release leverages the HACL* cryptographic library, which has been mathematically proven correct, and makes it readily available for Python developers through a simple and performant interface. Evercrypt aims to bring robust, verified cryptographic primitives to a wider audience, improving security and trustworthiness for applications that depend on strong cryptography. It offers a drop-in replacement for existing libraries, significantly enhancing the security guarantees without requiring extensive code changes.
Hacker News users discussed the implications of having 15,000 lines of verified cryptography in Python, focusing on the trade-offs between verification and performance. Some expressed skepticism about the practical benefits of formal verification for cryptographic libraries, citing the difficulty of verifying real-world usage and the potential performance overhead. Others emphasized the importance of correctness in cryptography, arguing that verification offers valuable guarantees despite its limitations. The performance costs were debated, with some suggesting that the overhead might be acceptable or even negligible in certain scenarios. Several commenters also discussed the challenges of formal verification in general, including the expertise required and the limitations of existing tools. The choice of Python was also questioned, with some suggesting that a language like OCaml might be more suitable for this type of project.
The increasing reliance on AI tools in Open Source Intelligence (OSINT) is hindering the development and application of critical thinking skills. While AI can automate tedious tasks and quickly surface information, investigators are becoming overly dependent on these tools, accepting their output without sufficient scrutiny or corroboration. This leads to a decline in analytical skills, a decreased understanding of context, and an inability to effectively evaluate the reliability and biases inherent in AI-generated results. Ultimately, this over-reliance on AI risks undermining the core principles of OSINT, potentially leading to inaccurate conclusions and a diminished capacity for independent verification.
Hacker News users generally agreed with the article's premise about AI potentially hindering critical thinking in OSINT. Several pointed out the allure of quick answers from AI and the risk of over-reliance leading to confirmation bias and a decline in source verification. Some commenters highlighted the importance of treating AI as a tool to augment, not replace, human analysis. A few suggested AI could be beneficial for tedious tasks, freeing up analysts for higher-level thinking. Others debated the extent of the problem, arguing critical thinking skills were already lacking in OSINT. The role of education and training in mitigating these issues was also discussed, with suggestions for incorporating AI literacy and critical thinking principles into OSINT education.
Verification-first development (VFD) prioritizes writing formal specifications and proofs before writing implementation code. This approach, while seemingly counterintuitive, aims to clarify requirements and design upfront, leading to more robust and correct software. By starting with a rigorous specification, developers gain a deeper understanding of the problem and potential edge cases. Subsequently, the code becomes a mere exercise in fulfilling the already-proven specification, akin to filling in the blanks. While potentially requiring more upfront investment, VFD ultimately reduces debugging time and leads to higher quality code by catching errors early in the development process, before they become costly to fix.
Hacker News users discussed the practicality and benefits of verification-first development (VFD). Some commenters questioned its applicability beyond simple examples, expressing skepticism about its effectiveness in complex, real-world projects. Others highlighted potential drawbacks like the added time investment for writing specifications and the difficulty of verifying emergent behavior. However, several users defended VFD, arguing that the upfront effort pays off through reduced debugging time and improved code quality, particularly when dealing with complex logic. Some suggested integrating VFD gradually, starting with critical components, while others mentioned tools and languages specifically designed to support this approach, like TLA+ and Idris. A key point of discussion revolved around finding the right balance between formal verification and traditional testing.
While implementing algorithms from Donald Knuth's "The Art of Computer Programming" (TAOCP), the author uncovered a few discrepancies. One involved an incorrect formula for calculating index values in a tree-like structure, leading to crashes when implemented directly. Another error related to the analysis of an algorithm's performance, where a specific case was overlooked, potentially impacting the efficiency calculations. The author reported these findings to Knuth, who confirmed the issues and issued corrections, highlighting the ongoing evolution and collaborative nature of perfecting even such a revered work. The experience underscores the value of practical implementation in verifying theoretical computer science concepts.
Hacker News commenters generally express admiration for both Knuth and the detailed errata-finding process described in the linked article. Several discuss the value of meticulous proofreading and the inevitability of errors, even in highly regarded works like The Art of Computer Programming. Some commenters point out the impressive depth of analysis involved in uncovering these errors, noting the specialized knowledge and effort required. A few lament the declining emphasis on rigorous proofreading in modern publishing, contrasting it with Knuth's dedication to accuracy and his reward system for finding errors. The overall tone is one of respect for Knuth's work and appreciation for the effort put into maintaining its quality.
This blog post explores how a Certificate Authority (CA) could maliciously issue a certificate with a valid signature but an impossibly distant expiration date, far beyond the CA's own validity period. This "fake future" certificate wouldn't trigger typical browser warnings because the signature checks out. However, by comparing the certificate's notAfter date with Signed Certificate Timestamps (SCTs) from publicly auditable logs, inconsistencies can be detected. These SCTs provide proof of inclusion in a log at a specific time, effectively acting as a timestamp for when the certificate was issued. If the SCT is newer than the CA's validity period but the certificate claims an older issuance date within that validity period, it indicates potential foul play. The post further demonstrates how this discrepancy can be checked programmatically using open-source tools.
Hacker News users discuss the practicality and implications of the blog post's method for detecting malicious Sub-CAs. Several commenters point out the difficulty of implementing this at scale due to the computational cost and potential performance impact of checking every certificate against a large CRL set. Others express concerns about the feasibility of maintaining an up-to-date list of suspect CAs, given their dynamic nature. Some question the overall effectiveness, arguing that sophisticated attackers could circumvent such checks. A few users suggest alternative approaches like using DNSSEC and DANE, or relying on operating system trust stores. The overall sentiment leans toward acknowledging the validity of the author's points while remaining skeptical of the proposed solution's real-world applicability.
The blog post details a formal verification of the standard long division algorithm using the Dafny programming language and its built-in Hoare logic capabilities. It walks through the challenges of representing and reasoning about the algorithm within this formal system, including defining loop invariants and handling edge cases like division by zero. The core difficulty lies in proving that the quotient and remainder produced by the algorithm are indeed correct according to the mathematical definition of division. The author meticulously constructs the necessary pre- and post-conditions, and elaborates on the specific insights and techniques required to guide the verifier to a successful proof. Ultimately, the post demonstrates the power of formal methods to rigorously verify even relatively simple, yet subtly complex, algorithms.
Hacker News users discussed the application of Hoare logic to verify long division, with several expressing appreciation for the clear explanation and visualization of the algorithm. Some commenters debated the practical benefits of formal verification for such a well-established algorithm, questioning the likelihood of uncovering unknown bugs. Others highlighted the educational value of the exercise, emphasizing the importance of understanding foundational algorithms. A few users delved into the specifics of the chosen proof method and its implications. One commenter suggested exploring alternative verification approaches, while another pointed out the potential for applying similar techniques to other arithmetic operations.
A VTuber's YouTube channel, linked to a Brand Account, was requested to verify ownership via phone number. Upon doing so, the channel's name and icon were permanently changed to match the Google account associated with the phone number, completely overwriting the VTuber's branding. YouTube support has been unhelpful, claiming this is intended behavior. The VTuber is seeking community support and attention to the issue, warning others with Brand Accounts to avoid phone verification, as it risks irreversible damage to their channel identity.
HN commenters were largely skeptical of the YouTuber's claims, suspecting they had misunderstood or misrepresented the situation. Several pointed out that YouTube likely wouldn't overwrite an existing Google account with a brand account's information and suggested the user had accidentally created a new account or merged accounts unintentionally. Some offered technical explanations of how brand accounts function, highlighting the separation between personal and brand channel data. Others criticized the YouTuber for not contacting YouTube support directly and relying on Reddit for technical assistance. A few commenters expressed general frustration with YouTube's account management system, but most focused on the plausibility of the original poster's story.
Summary of Comments ( 30 )
https://news.ycombinator.com/item?id=43745987
Hacker News users discussed Verus's potential and limitations. Some expressed excitement about its ability to verify low-level code, seeing it as a valuable tool for critical systems. Others questioned its practicality, citing the complexity of verification and the potential for performance overhead. The discussion also touched on the trade-offs between verification and traditional testing, with some arguing that testing remains essential even with formal verification. Several comments highlighted the challenge of balancing the strictness of verification with the flexibility needed for practical systems programming. Finally, some users were curious about Verus's performance characteristics and its suitability for real-world projects.
The Hacker News post "Verus: Verified Rust for low-level systems code" (https://news.ycombinator.com/item?id=43745987) has generated several comments discussing various aspects of the Verus verification system for Rust.
Several commenters express interest in the project and its potential. One notes the significance of bringing verification tools to a language like Rust, which is gaining traction in systems programming, suggesting it could lead to more robust and reliable systems. Another appreciates the focus on low-level code, acknowledging the challenge of verification in this domain and hoping for positive outcomes. Someone also mentions the potential of combining Verus with other Rust-based verification efforts for a comprehensive solution.
Some discussion revolves around the practicality and usability of formal verification tools. One commenter highlights the steep learning curve associated with formal verification, suggesting that broader adoption hinges on simplifying the process. Another expresses concern about the potential for proofs to become overly complex and difficult to manage, particularly in large projects. There's also a question about the performance overhead introduced by verification and whether it's acceptable for performance-sensitive applications.
The integration of Verus with existing Rust development workflows is another topic of discussion. A commenter inquires about IDE support for Verus, specifically within Visual Studio Code, emphasizing the importance of tooling for practical use. Another raises the point that effective verification often requires significant changes to coding style and project structure, potentially impacting development practices.
A few comments delve into the technical details of Verus. One commenter mentions the use of SMT solvers (Satisfiability Modulo Theories) and their role in the verification process. Another asks about the specific logic used by Verus, such as higher-order logic or separation logic. There's also a comment inquiring about the handling of concurrency and parallelism in Verus, recognizing the challenges of verifying concurrent code.
Finally, a commenter points out the connection between Verus and the Dafny verification system, suggesting that Verus builds upon some of the concepts and ideas from Dafny. They express curiosity about the differences and improvements introduced by Verus.
In summary, the comments reflect a mixture of enthusiasm, cautious optimism, and pragmatic concerns about the challenges of integrating formal verification into real-world Rust projects. They touch upon topics ranging from usability and tooling to technical aspects of the verification process and its potential impact on performance and development workflows.