This post briefly describes how to utilise AES to encrypt and decrypt files with OpenSSL.
- Generate 256 Bit Key Online
- Generate 256 Bit Key From Passphrase Windows 10
- Generate 256 Bit Key
- Generate 256 Bit Key From Passphrase Windows 7
“secret” is a passphrase for generating the key. The output from the command is similar to: 128-bit: salt=92AE31A79FEEB2A3 key=770A8A65DA156D24EE2A42 iv=F55037B8DAEF761B189D12; 192-bit: salt=D495560961CCCFE0 key=4D92199549E0F2EF009B4160F3582E557F3EF8 iv =35B2FF0795FB84BBD666DB8430CA214E; 256-bit. WEP Key Generator. To generate a random WEP key, select the bit key length to generate and press the corresponding button; the ASCII or HEX key can then be copied to your clipboard manually or via the copy to clipboard button to the right of the generated key text field. You can also generate a custom WEP key based on your own pass phrase or other input.
AES - Advanced Encryption Standard (also known as Rijndael).
OpenSSL - Cryptography and SSL/TLS Toolkit
![Generate 256 Bit Key From Passphrase Generate 256 Bit Key From Passphrase](/uploads/1/2/6/0/126066162/269851488.jpg)
We’ll walk through the following steps:
- Generate an AES key plus Initialization vector (iv) with
openssl
and - how to encode/decode a file with the generated key/iv pair
Note: AES is a symmetric-key algorithm which means it uses the same key during encryption/decryption.
Generating key/iv pair
We want to generate a
256
-bit key and use Cipher Block Chaining (CBC).The basic command to use is
openssl enc
plus some options:-P
— Print out the salt, key and IV used, then exit-k <secret>
or-pass pass:<secret>
— to specify the password to use-aes-256-cbc
— the cipher name
Note: We decided to use no salt to keep the example simple.
Issue
openssl enc --help
for more details and options (e.g. other ciphernames, how to specify a salt, …).Encoding
Generate 256 Bit Key Online
Let's start with encoding
Hello, AES!
contained in the text file message.txt
:Generate 256 Bit Key From Passphrase Windows 10
Decoding
Generate 256 Bit Key
Decoding is almost the same command line - just an additional
-d
for decrypting:Note: Beware of the line breaks
While working with AES encryption I encountered the situation where the encoder sometimes produces base 64 encoded data with or without line breaks...
Generate 256 Bit Key From Passphrase Windows 7
Short answer: Yes, use the OpenSSL
-A
option.