From owner-freebsd-security@FreeBSD.ORG Mon Jun 25 10:36:02 2012 Return-Path: Delivered-To: freebsd-security@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 8AAFC106564A for ; Mon, 25 Jun 2012 10:36:02 +0000 (UTC) (envelope-from azet@azet.org) Received: from mail-wg0-f50.google.com (mail-wg0-f50.google.com [74.125.82.50]) by mx1.freebsd.org (Postfix) with ESMTP id 1755B8FC19 for ; Mon, 25 Jun 2012 10:36:01 +0000 (UTC) Received: by wgbds11 with SMTP id ds11so3731608wgb.31 for ; Mon, 25 Jun 2012 03:36:01 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:content-transfer-encoding:x-gm-message-state; bh=mEP6kVM6RFBp2mDXMTdtGNQ6VrmzMcvQLbjx/n3DTxk=; b=CLbI8gd+w7YfMuKgBFFEDoLJFVeepiLq/cXzvXbI6BAdalV0OleGBsnUfBwBBkgYLH KkWvy/XNRXyHRUEq9FDSrEmkP3uoVOE5Z4Pooz3kw4bAKdLKQoc6z2mTduHjk3MxS/jr X4Jk7gRPnPq0/FHoGeh234QJW2DYFr6ZyNL/wqnrcAJP/Y4TQS5EoipXt2S+NV945faS y/HfV9QPK6Cs2cNy6b+RVq1AoQOl3CfPrNgFaJ+LEoEPMXFTLHg1AMGDO9vBbmHWYlNG 0syNdi9kVPuqREEW1kBURhupKGooX9B4WXmJ9ENhDM6fLMegMFt2nKWcywfEcHCnN3ja mHFw== MIME-Version: 1.0 Received: by 10.180.79.229 with SMTP id m5mr23536033wix.13.1340620560903; Mon, 25 Jun 2012 03:36:00 -0700 (PDT) Received: by 10.194.32.6 with HTTP; Mon, 25 Jun 2012 03:36:00 -0700 (PDT) In-Reply-To: References: Date: Mon, 25 Jun 2012 10:36:00 +0000 Message-ID: From: Aaron Zauner To: freebsd-security@freebsd.org Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Gm-Message-State: ALoCoQml4NHyIJ5bDg5rbdsX4v2uw3NTVT+Xifr3xorI+F59Dt+t3JOlYj5SY704516m8d8av3Nu Subject: Fwd: Default password encryption method. X-BeenThere: freebsd-security@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Security issues \[members-only posting\]" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 25 Jun 2012 10:36:02 -0000 so what about bcrypt? http://en.wikipedia.org/wiki/Bcrypt On Thu, Jun 21, 2012 at 7:38 PM, Aaron D. Gifford wr= ote: > On Tue, Jun 19, 2012 at 12:14 PM, Simon L. B. Nielsen = wrote: > ..snip... >> The FreeBSD Security Team is also looking at (/poking people to look at) >> solutions which will improve the the time it takes to brute force passwo= rds >> significantly more. >> >> -- >> Simon > > I'd love to see PBKDF2 as a password hashing method. Yes, it's meant > for deriving key material, but it can function similarly. =C2=A0It has th= e > flexibility of allowing different hashes being used for the HMAC PRNG > portion, and the ability to vary/specify the number of iterations. > No, it's not memory complex like scrypt, but personally I prefer to > not yet have memory usage involved. =C2=A0I could foresee PBKDF-HMAC-SHA5= 12 > or PBKDF-HMAC-SHA256. =C2=A0I would select the quantity of output to matc= h > the hash size selected (i.e. if I use HMAC-SHA512 for the PRNG portion > of PBKDF2, I would have PBKDF2 generate 512 bits of output to store in > my password database). > > PBKDF2(pseudo-random-function, password, salt, iterations, output-size) > > I'd offer HMAC-SHA256 and HMAC-SHA512 initially for the > pseudo-random-function parameter. > > And I'd select output-size as mentioned above, 256 bits for HMAC-SHA256, = etc. > > As for iterations, how hard would it be to allow for more variation in > the base-64 encoded salt field in the master password database such > that for a PBKDF2 scheme, the field used as salt would actually be > three fields, an 4-bit pseudo-random-function selector and a 32-bit > unsigned integer number of iterations (or 36 bits, which base-64 > encoded would be 6 characters) followed by a variable length salt > (i.e. any length permitted by the master password database structure > up to the '$' character delimiter)? > > Or one could simply define separate algorithms for each PRF > (pseudo-random-function) available. > > But, storing the number of iterations with the stored salt has the > benefit of not requiring a new algorithm be defined when one wants to > increase the default security level of hashed passwords. =C2=A0One merely > need to change a system setting to default to use more iterations. > And password databases from other systems with a higher or lower > setting would still be readable and usable. > > Brainstorming session over... for now. > > Aaron out. > _______________________________________________ > freebsd-security@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-security > To unsubscribe, send any mail to "freebsd-security-unsubscribe@freebsd.or= g"