Encrypting and decrypting files using OpenSSL

If you need to just encrypt file without additional tool on Linux box, you can use OpenSSL for this task. It may help you sent sensitive information trough unsecure channels.

You can use varios encryption algorithms ( I'm using AES 128 in this example): 

root@vo:~# cat test.txt
test test test
root@vo:~# openssl enc -aes-128-cbc -in test.txt -out test.txt.enc 
enter aes-128-cbc encryption password: 
Verifying - enter aes-128-cbc encryption password: 
root@vo:~# rm test.txt

 And after use "-d" option for decrypting:

root@vo:~# openssl enc -d -aes-128-cbc -in test.txt.enc -out test.txt 
enter aes-128-cbc decryption password: 
root@vo:~# cat test.txt 
test test test 

 And thats all :)