The Password Hashing Competition (PHC) is an effort organized to
identify new password hashing schemes in order to improve on the
state-of-the-art (PBKDF2, scrypt, etc.), and to encourage the use of strong password protection.
Applications include for example authentication to web services, PIN
authentication on mobile devices, key derivation for full disk
encryption, or private keys encryption.
Motivations behind the PHC include:
The poor state of passwords protection in web services: passwords are too
often either stored in clear (these are the services that send you your
password by email after hitting "I forgot my password"), or just hashed
with a cryptographic hash function (like MD5 or SHA-1), which exposes
users' passwords to efficient brute force cracking methods.
The low variety of methods available: the only standardized construction
is PBKDF2 (PKCS#5,
NIST SP 800-132), and there are mainly just two alternatives: bcrypt and scrypt.
A number of new ideas discussed within the security and cryptography
communities, but which have not yet led to a concrete proposal.
(For more information on the topic of password hashing, a quick and
comprehensive introduction is this presentation.)
To identify new password hashing schemes suitable for widespread
adoption, the PHC follows the model of focused cryptographic
competitions such as AES, eSTREAM, or SHA-3 (see the Cryptographic competitions
The PHC is organized by a panel of experts consisting of
Tony Arcieri (@bascule, Square)
Jean-Philippe Aumasson (@veorq, Kudelski Security)
Dmitry Chestnykh (@dchest, Coding Robots)
Jeremi Gosney (@jmgosney, Stricture Consulting Group)
Russell Graves (@bitweasil, Cryptohaze)
Matthew Green (@matthew_d_green, Johns Hopkins University)
Peter Gutmann (University of Auckland)
Pascal Junod (@cryptopathe, HEIG-VD)
Poul-Henning Kamp (FreeBSD)
Stefan Lucks (Bauhaus-Universität Weimar)
Samuel Neves (@sevenps, University of Coimbra)
Colin Percival (@cperciva, Tarsnap)
Alexander Peslyak (@solardiz, Openwall)
Marsh Ray (@marshray, Microsoft)
Jens Steube (@hashcat, Hashcat project)
Steve Thomas (@Sc00bzT, TobTu)
Meltem Sonmez Turan (NIST)
Zooko Wilcox-O'Hearn (@zooko, Least Authority Enterprises)
Christian Winnerlein (@codesinchaos, Pactas)
Elias Yarrkov (@yarrkov)
These experts are responsible for the selection of a portfolio
of schemes, based on the public contribution and on their assessment of
the submissions received. They will be permitted to submit schemes.
The PHC is organized by a group of individuals, not by a standardization
body. However this does not exclude the future standardization of one or
more of the schemes selected.
The PHC is expected to rely in great part on contributions from the
public, including for third-party implementations, cryptanalytic
attacks, and optimized GPU or hardware crackers.