cryptolinguistics - well said!

From Matt Blaze’s blog:
We often say that researchers break poor security systems and that feats of cryptanalysis involve cracking codes. As natural and dramatic as this shorthand may be, it propagates a subtle and insidious fallacy that confuses discovery with causation. Unsound security systems are “broken” from the start, whether we happen to know about [...]

useful analysis tools - usage reminder

How to obtain multiple files during a capture:
$ tethereal -i <interface> -a filesize:3000 -b 14 -s 96 -w <capture_file>
(3MB files of 96 bytes length)
NOTE: tcpdump defaults to 96 bytes length, also, but I am not sure if it supports ring buffer?!?
******
If multiple files matching the regexp FOOBAR are to be merged :
$ mergecap -w bigfile.cap [...]

tunneling over SSH

Generic:
$ ssh -N -f -L <local_port>:<end_server>:<end_port> user@ssh_intermediary_server
NOTE: if using auth. w/keys and no passwd, the last part (user@… is not needed
Example:
$ ssh -f -N -L 8025:smtp.comcast.net:25 my_home_machine -L 8110:mail.comcast.net:110 my_home_machine
allows me to use the email client on a laptop, pointing to localhost:8025 for SMTP services, and localhost:8110 for POP3 services associated with my Comcast account, [...]

SSH with keys

Execute on local host, under user’s pwd:
$ mkdir -p ~/.ssh
$ chmod 700 ~/.ssh
$ cd ~/.ssh
$ ssh-keygen -t dsa
Copy the public key to the remote host
$ scp -p id_dsa.pub remoteuser@remotehost:
Password: *********
Log into remote host and install public key
$ ssh remoteuser@remotehost
Password: ********
remotehost$ mkdir -p ~/.ssh
remotehost$ chmod 700 ~/.ssh
remotehost$ cat ida_dsa.pub >> ~/.ssh/authorized_keys
remotehost$ chmod 600 ~/.ssh/authorized_keys
remotehost$ mv id_dsa.pub [...]