2012-02-07

Be careful with hashmaps

Categories: coding, security

As you remember from long ago hashes are O(1) best case, but can be O(n) if you get hash collisions. And if you're adding n new entries that means O(n^2).

I thought I'd take a look at the hash_set/hash_map GNU C++ extension.

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2012-02-05

Benchmarking TPM-backed SSL

Categories: hsm, network, security, tpm


As you can plainly see from this graph, my TPM chip can do approximately 1.4 SSL handshakes per second. A handshake takes about 0.7 seconds of TPM time, so when two clients are connecting the average connect time is 1.4 seconds. This means probably not useful on server side, but should be good for some client side applications.

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2012-02-04

TPM-backed SSL

Categories: coding, hsm, network, security, tpm

This is a short howto on setting up TPM-backed SSL. This means that the secret key belonging to an SSL cert is protected by the TPM and cannot be copied off of the machine or otherwise inspected.

Meaning even if you get hacked the attackers cannot impersonate you, if you manage to kick them off or just shut down the server. The secret key is safe. It has never been outside the TPM and never will be.

This can be used for both client and server certs.

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