General :: File Encryption In A Bash Script Without Explicity Providing Password?

I want to automate the following manual process.Currently, I am encryptying a set of files using openssl as follows:Encrypt file.txt to file.out using 256-bit AES in CBC mode $ openssl enc -aes-256-cbc -salt -in file1 -out file1.enI am then prompted for a password, which is then used to encrypt the fileWhen decrypting, I type $ openssl enc -d -aes-256-cbc -infile1.enc -out fileI am then prompted for the password - which again, I manually type.I want to automate this process of en/decryption - so I need to find a way of providing openssh with the password.

My first thought is whether it is possible to read the password from a file (say)? Or is there a better way of doing this?Also, I suppose that I will have to place restriction on who can view the password file - otherwise, that defeats the whole objective of using a password. I am thinking to run the bash script as a specific user, and then give only that user read rights to the contents of that file.Is this the way its done - or is there a better way?Ofcourse all of this leads to yet another question - which is, how to run a bash script as another user - without having to type the user pwd at the terminal.