Last week I added a new experience to my list. Our company purchased a domain (smpp.com) from buydomains.com. I must say I was a little skeptical about paying a “horrendous” amount of money, using a credit card, for a domain. However, I must say the process was very swift and completed within 36 hours. Kudos to buydomain.com for that.

When the purchase completed the domain can be maintained via a control panel at domaindiscovery.com. From there DNS servers could be changed and possibly a transfer to another registrar initiated. Simple enough.

So, if you find a domain that you want badly, it is for sale from buydomains.com and you can agree on a price, then I think you can safely go ahead and acquire the domain.

Our mail server receives around 10.000 e-mails per day. On weeekdays around 70% is spam, during weekends more than 90% is spam. Lately our mailserver load has been very high leading to poor reponse times. As a result we decided to implement greylisting.

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Now I have finished a PAM module for sending One-Time Passwords (OTPs) via SMS when using Pluggable Authentication Module (PAM) in Linux.

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We have experienced high load on one of our web servers lately (Apache 2.0.59 on Linux). So, I started thinking about how to analyze this in a bit more detail. We are running multiple virtual hosts (around 60) so when using tcpdump it is not easy to see which URLs are requested, therefore I looked around for some HTTP-oriented sniffer. My search ended with “urlsnarf” from the “dsniff” package.

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I have just started writing a PAM module for authentication using One Time Passwords (OTP) sent to the user’s mobile phone via SMS.

The idea is adding a PAM module to the stack for sshd (or other services) with the following functionality:

• First use “normal” authentication of type “requisite”. That is if the normal username/password combination is not entered correctly by the user, the user is rejected.
• Check if the user originates from an IP address configured as trusted. If yes, approve authentication without further action.
• For non-trusted IP addresses check if the user is configured in the “OTP database” and if yes, generate an OTP and send to the user’s mobile phone.
• The user is prompted for the OTP and if entered correctly authectication is approved. For incorrect password start the authentication process all over again.

The PAM module will send the password using a HTTP POST on the format used by our own SMS Submit service. However, letting the URL be configurable the module can be configured to use any SMS service that can use the parameters sent.

First objective is to make it run in Linux, but then it would be nice to be able to support other operating systems as well.