Monthly Archives: April 2012
Notice: This method will probably not work on all YouTube videos.
Remember the good old days when you could pause a flash video, let it buffer and play the video with the media player of your choice by opening the corresponding file from the /tmp directory?
Well that’s still possible. However the video-files are deleted from the /tmp directory. So you need to find the PID of the flash plugin-container to open the video from /proc/PID/fd/.
Read the rest of this entry
First you have to create a public, private key pair. For this you can use the command-line tool sshkey-gen.
Change the directory to “~/.ssh” (create it, if it does not exist).
Create key pair
Now let’s create the key pair. In this example I will use RSA with 4096 Bit
ssh-keygen -t rsa -b 4096
Enter a passphrase if you want but you don’t have to. I recommend to enter a passphrase.
Transfer public key to ssh server
To transfer the public key to the ssh server you can use ssh-copy-id.
ssh-copy-id -i ~/.ssh/id_rsa.pub HOST
Login with key
Now you should be able to login with the created key.
Linux saves the ssh host keys in ~/.ssh/known_hosts. You can manage these ssh host keys with the command ssh-keygen.
Search for a specific host (in known_hosts):
ssh-keygen -F HOSTNAME
Remove a specific host:
ssh-keygen -R HOSTNAME
To add a new ssh host key you can use ssh-keyscan. This command print the ssh host key on the stdout. So we have to append this key to the known_hosts file.
ssh-keyscan -H HOSTNAME >> ~/.ssh/known_hosts
Openssl comes with lots of cipher types. At the end of the post you can find a list of all cipher types.
We want to encrypt the file test.txt with AES 256 Bit CBC. The name of the encrypted file is test.enc:
openssl enc -aes-256-cbc -in test.txt -out test.enc
We want to decrypt the file test.enc with AES 256 Bit CBC:
openssl enc -d -aes-256-cbc -in test.enc -out test.txt
Openssl will ask you for the passphrase.
You can use the Linux command-line too pdftk to merge several PDF files into one.
You have two PDF file a.pdf and b.pdf and want to merge these two files into one file named c.pdf.
pdftk a.pdf b.pdf cat output c.pdf
Another way to do this, is to use handles:
pdftk A=a.pdf B=b.pdf cat A B output c.pdf
Last update: 14.06.2015