crypto_cmds

#############################
# GNUPG
#############################

# generate a keypair
gpg --gen-key
# export ones public key
gpg --armor --output pubkey.txt --export 'My name'
# send the key on the server (easier with kgpg)
gpg --send-keys 'My name' --keyserver hkp://subkeys.pgp.net

# import someone else's key
gpg --import key.asc
gpg --search-keys 'tnagy1024@gmail.com' --keyserver hkp://subkeys.pgp.net
# encrypt a file
gpg --encrypt --recipient 'tnagy1024@gmail.com' foo.txt
# decrypt a file
gpg --output foo.txt --decrypt foo.txt.gpg

#############################
# LINUX
#############################

# partition creation using ‘dd’
dd if=/dev/urandom of=/root/linux.bin bs=1024k count=278
dd if=/dev/zero of=/root/linux.bin bs=1024k count=4489 (dvd R)
dd if=/dev/zero of=/root/linux.bin bs=1024k count=4450 (dvd RW)
dd if=/dev/zero of=/root/linux.bin bs=1024k count=700 (cdrom de 700 Mb)

# filesystem creation
mkfs -t ext2 /dev/loop0
tune2fs -m0 -c0 -i0 /dev/loop0

# script for mounting the volume
#! /bin/sh
DEVICE=/root/linux.bin
sudo /sbin/modprobe cryptoloop
sudo /sbin/modprobe aes
sudo /sbin/losetup -eaes256 -C7 /dev/loop0 $DEVICE
sleep 1
sudo mount /dev/loop0 /crypt

# script for unmounting
#! /bin/sh
sudo umount /crypt
sudo /sbin/losetup -d /dev/loop0

#############################
# SSH
#############################

# Key creation
ssh-keygen -t rsa

then copy ~/.ssh/id_rsa.pub on the remote server

# To avoid retyping the password over and over again, edit ~/.profile
SSHAGENT=/usr/bin/ssh-agent
SSHAGENTARGS="-s"
if [ -z "$SSH_AUTH_SOCK" -a -x "$SSHAGENT" ]; then
eval `$SSHAGENT $SSHAGENTARGS`
trap "kill $SSH_AGENT_PID" 0
fi

# for the fist time, call:
ssh-add ~/.ssh/id_dsa