We evaluate two decades of proposals to replace text passwords for general-purpose user authentication on the web using a broad set of twenty-five usability, deployability and security benefits that an ideal scheme might provide. The scope of proposals we survey is also extensive, including password management software, federated login protocols, graphical password schemes, cognitive authentication schemes, one-time passwords, hardware tokens, phone-aided schemes and biometrics. Our comprehensive approach leads to key insights about the difficulty of replacing passwords. Not only does no known scheme come close to providing all desired benefits: none even retains the full set of benefits that legacy passwords already provide. In particular, there is a wide range from schemes offering minor security benefits beyond legacy passwords, to those offering significant security benefits in return for being more costly to deploy or more difficult to use. We conclude that many academic proposals have failed to gain traction because researchers rarely consider a sufficiently wide range of real-world constraints. Beyond our analysis of current schemes, our framework provides an evaluation methodology and benchmark for future web authentication proposals.

/pdf/the-quest-to-replace-passwords-a-framework-for-comparative-3ohujijx0b.pdf

The Quest to Replace Passwords: A Framework for Comparative Evaluation of Web Authentication Schemes

BSeIn: A blockchain-based secure mutual authentication with fine-grained access control system for industry 4.0

This document describes an extension of one-time password (OTP)
algorithm, namely the HAMC-Based One-Time Password (HOTP) Algorithm as
defined in RFC 4226, to support time-based moving factor. The HOTP
algorithm specifies an event based OTP algorithm where the moving
factor is an event counter. The present work bases the moving factor
on a time value. A time-based variant of the OTP algorithm provides
short-lived OTP values, which are desirable for enhanced security.
The proposed algorithm can be used across a wide range of network
applications ranging from remote Virtual Private Network (VPN) access,
Wi-Fi network logon to transaction-oriented Web applications. The
authors believe that a common and shared algorithm will facilitate
adoption of two-factor authentication on the Internet by enabling
interoperability across commercial and open-source implementations.

TOTP: Time-Based One-Time Password Algorithm

HMAC was proved in [3] to be a PRF assuming that (1) the underlying compression function is a PRF, and (2) the iterated hash function is weakly collision-resistant. However, recent attacks show that assumption (2) is false for MD5 and SHA-1, removing the proof-based support for HMAC in these cases. This paper proves that HMAC is a PRF under the sole assumption that the compression function is a PRF. This recovers a proof based guarantee since no known attacks compromise the pseudorandomness of the compression function, and it also helps explain the resistance-to-attack that HMAC has shown even when implemented with hash functions whose (weak) collision resistance is compromised. We also show that an even weaker-than-PRF condition on the compression function, namely that it is a privacy-preserving MAC, suffices to establish HMAC is a secure MAC as long as the hash function meets the very weak requirement of being computationally almost universal, where again the value lies in the fact that known attacks do not invalidate the assumptions made.

/pdf/new-proofs-for-nmac-and-hmac-security-without-collision-45cuw77mm7.pdf

New proofs for NMAC and HMAC: security without collision-resistance

HMAC was proved in Bellare et al. (Advances in Cryptology---CRYPTO'96, Springer, Berlin, Heidelberg, 1996) to be a PRF assuming that (1) the underlying compression function is a PRF, and (2) the iterated hash function is weakly collision resistant. However, subsequent attacks showed that assumption (2) is false for MD5 and SHA-1, removing the proof-based support for HMAC in these cases. This paper proves that HMAC is a PRF under the sole assumption that the compression function is a PRF. This recovers a proof-based guarantee since no known attacks compromise the pseudorandomness of the compression function, and it also helps explain the resistance to attack that HMAC has shown even when implemented with hash functions whose (weak) collision resistance is compromised. We also show that an even weaker than PRF condition on the compression function, namely that it is a privacy-preserving MAC, suffices to establish HMAC is a secure MAC as long as the hash function meets the very weak requirement of being computationally almost universal, where again the value lies in the fact that known attacks do not invalidate the assumptions made.

https://link.springer.com/content/pdf/10.1007%2F11818175_36.pdf

New Proofs for NMAC and HMAC: Security without Collision Resistance

This document describes an algorithm to generate one-time password
values, based on Hashed Message Authentication Code (HMAC). A security
analysis of the algorithm is presented, and important parameters
related to the secure deployment of the algorithm are discussed. The
proposed algorithm can be used across a wide range of network
applications ranging from remote Virtual Private Network (VPN) access,
Wi-Fi network logon to transaction-oriented Web applications. This
work is a joint effort by the OATH (Open AuTHentication) membership to
specify an algorithm that can be freely distributed to the technical
community. The authors believe that a common and shared algorithm will
facilitate adoption of two-factor authentication on the Internet by
enabling interoperability across commercial and open-source
implementations. This memo provides information for the Internet
community.

/pdf/hotp-an-hmac-based-one-time-password-algorithm-48i4kj9bla.pdf

Mihir Bellare

Papers

HOTP: An HMAC-Based One-Time Password Algorithm