Australian Gov't Offers $560k Cryptographic Protocol For Free

mask.of.sanity writes "Australia's national welfare agency will release its 'unbreakable' AU$560,000 smart card identification protocol for free. The government agency wants other departments and commercial businesses to adopt the Protocol for Lightweight Authentication of ID (PLAID), which withstood three years of design and testing by Australian and American security agencies. The agency has one of Australia's most advanced physical and logical converged security systems: staff can access doors and computers with a single centrally-managed identity card, and user identities can be automatically updated as employees leave, are recruited or move to new departments. PLAID, which will be available soon, is to be used in the agency's incoming fleet of contact-less smartcards that are currently under trial by staff. It will replace existing identity cards that operate on PKI encryption."

Comments

A little more info

[explosivejared]

Here is a briefing on the PLAID 6 protocol with more specifics on the actual algorithms and cryptography in general involved. PDF link if the first one doesn't work for you.

Re:A little more info

[TechyImmigrant]

The protocol looks unremarkable. They pass some entropy and IDs back and forth, using conventional standards based encryption and hash algorithms.

Their problem is keeping the cards secure and they state clearly that they are using commercially available smart cards.

There are secrets in the cards, an RSA private key and an AES master key. The bigger problem is keeping these secrets in the cards and distributing the keys to cards. The PLAID protocol has no bearing on these matters.

Re:A little more info

[swillden]

There are secrets in the cards, an RSA private key and an AES master key. The bigger problem is keeping these secrets in the cards and distributing the keys to cards. The PLAID protocol has no bearing on these matters.

Which is fine, because those problems are easily solved.

Commercially-available smart cards provide a rather high degree of security. Extracting keys from them isn't impossible (nothing is), but it is very difficult and expensive. I design high security systems for a living, and we have no concerns about the security of the cards themselves, because experience shows it's just not an issue.

What we do focus on is the security of the issuance process, because that's where those keys get injected. That problem is also solvable, mainly by performing the key injection in secure facilities using highly secure devices (FIPS 140-2 level 4 certified hardware security modules). It's expensive and complex (from a management and process perspective, not a technical perspective), but a high degree of security is achievable.

The protocol looks unremarkable. They pass some entropy and IDs back and forth, using conventional standards based encryption and hash algorithms.

It is unremarkable, which is one of its most significant strengths. It's just a lighter-weight approach to the problem, one that can be implemented efficiently on current-generation hardware. Previously, PK authentication on smart cards was considered too slow to use for physical access control and other applications where sub-second authentication was required. Faster smart cards coupled with a lightweight authentication protocol mean that PK authentication can be completed reliably in as little as 200 ms. That's fast enough to use it for transit applications.

PLAID 6 Protocol

[Anonymous Coward]

* Uses existing off-the-shelf symmetric and asymmetric crypto algorithms (SHA1, AES 256, RSA 1024, RSA 1984) tied together via the PLAID protocol
- Note - Neither SHA256 nor ECC are used at this time because production cards are either not obtainable from all vendors nor do they achieve the required performance, (in spite of theoretical advantage of ECC)
- Note - RSA 1984 is a trade off between performance and security, and ensuring the transaction fits in one APDU command.
* Fast & simple - less than 1/2 second (400ms) and the Java Card - applet is extremely small (about 4 Kb)
* Not clone-able, re-playable or subject to privacy or identity leakage
* Same protocol can be used for PACS/LACS & contact/contactless
* PIN can be verified when card-not-present by comparing PIN hash
- Saves user having to hold contactless card to reader during typical PKI session
* Mutual authentication Protocol
* Algorithms used are commercially available on virtually all modern smartcards including Java
Card, MULTOS, most SIMs and many proprietary cards
* Algorithms and their selected key lengths have been tested on production cards and devices to ensure speeds are real, not theoretical

* No IP issues - IP was developed solely by the Australian Government by its agency, Centrelink, and will be openly and freely licensed
* Designed to be used either stand-alone or as a bootstrap into other specifications like Australian IMAGE, US PIV, ICAO Passports etc.
* Supports multiple concurrent specs dependant on device request to card
- i.e. Card could supply Weigand number or CHUID or Centrelink CSIC or Passport MRZ etc etc dependant on use case
* Supports multiple (256) key sets dependant on device request to card
- i.e. there might be a "perimeter key set" and a "high security key set" and a "LACS key set" and an "administrative key set" etc etc and the terminal device only requests the one it requires, reducing the possibility of compromise of the others.
- The key sets can be rolled, by loading spare unused key sets (up to 255) in case of compromise (memory is the limitation)
* Optionally provides session keys for higher level specs
* Protocol can be registered and implemented under ISO/IEC 24727-3 and 6, and either used under ISO/IEC 24727or implemented separately

However:
Slightly slower than existing physical access Tag and proprietary solutions (by 0.2 to 0.3 seconds)
- Keys MUST be distributed & managed
* Vendors need to build key management for PLAID into existing or new key management systems. (Centrelink vendor is doing this for LACS)
* PACS using older Weigand technologies need secure SAM devices in the readers
* Newer PACS can utilise back end HSM devices/SAMs on the network or in distribution frames

Re:I laugh ...

[smallfries]

That looks familiar but I can't remember the name, what scheme is it?

The likelihood of breaking it is genuinely 1 in 2^n and can only be broken by brute force attack.

That's not strictly true. Although the discrete log problem is hard it is still a computational assumption. Proving that 2^n is a lower bound would be a significant achievement. This scheme is only "unbreakable" in the sense that RSA is - breaking it requires solving a problem that we suspect, but are unable to prove, is very hard.

Re:Yeah Right...

[swillden]

Given Australian government's views on privacy, I wonder when the back door will be discouvered? Or is looking for it agianst the law?

Look at the protocol. It's so simple that there's virtually no way for a back door to exist.

Implementations can have back doors, of course, but that's a separate issue.