Fabian Lee : Software Engineer

Linux: using openssl to encrypt and decrypt files and strings

January 25, 2023
Categories: Linux

If you need a way to simply encrypt and decrypt files or strings with a symmetric key (same password for encryption and decryption), openssl provides this functionality. Be sure to avoid weak ciphers such as 3DES, and employ salt as well as PBKDF2 iterations to reduce vulnerability to brute force attacks. Here is a simple … Linux: using openssl to encrypt and decrypt files and strings

Bash: Renaming files using shell parameter expansion

January 29, 2020
Categories: Scripting

Shell parameter expansion provides various ways to manipulate strings, and a convenient way to succinctly express renaming a set of files. In its simplest form, parameter expansion is simply ${parameter}. But look at these examples: $ mystr=”TheQuickBrownFox.jpg” # chop off last 4 digits $ echo ${mystr:0:-4} TheQuickBrownFox # truncate end of string ‘.jpg’ $ echo … Bash: Renaming files using shell parameter expansion