How to use 3DES in a micro?

ElderUberGeek escribió:

Yes.

Try googling OpenSSL.

In symmetric crypto (like 3DES), the key must be known by both units. This can be done installing the key at production time in both units. Or, you can install the key in a unit, and deliver it to the other unit via asymmetric crypto. Or, you can _generate_ the key in a unit as needed, and deliver it to the other unit via asymmetric crypto. Other scenarios are possible as well.

IMHO, a look at

Start with "Applied Cryptography" by Bruce Schnauer. Excellent book, a must for anyone implementing security algorithms.

Yes. However the encryption/decryption speed may be the issue. Depending on the algorithm and CPU, you can expect something like 1 kbyte/sec per one MIPS.

Avoid using anyone's code until you yourself realize the main concepts. You can seriously compromise the security. There are countless examples of the security flaws because someone used the code of the shelf brainlesly.

Keyword: "public key cryptography"

Vladimir Vassilevsky DSP and Mixed Signal Design Consultant

The name's Schneier.

"ElderUberGeek" skrev i meddelandet news: snipped-for-privacy@k79g2000hse.googlegroups.com...

There is a 3DES H/W block in the AT91SAM7XC128/256. These parts cannot be exported outside E.U, US/Canada, Austrealia,New Zealand or Japan without applying for an export license though.

Here's an implementation of DES and SKIPJACK on Microchip PIC:

The DES code is about 700 instructions and SKIPJACK is around 300 instructions so they can easily be implemented on even the low end PICs.

Actually, as far as I have been looking in to it, AES is the way to go.

Any idea about libraries or maybe an external chip?

You can always implement it into an FPGA or another controller.

Rene

ElderUberGeek wrote:

No. XTEA is the way to go.

The AES standard description with the reference C code is available from NIST web site.

Vladimir Vassilevsky DSP and Mixed Signal Design Consultant

"ElderUberGeek" skrev i meddelandet news: snipped-for-privacy@r29g2000hsg.googlegroups.com...

AT91SAM7XC128/256 has AES as well as 3DES. (Should have been in the first mail)

This will give you a single chip solution with ARM7TDMI

What else do you need?