# Asymmetric File Encrypt and Decrypt

* Let’s generate some public/private keys and encrypt/decrypt a message!
* To generate a private key we use the following command (8912 creates the key 8912 bits long):

```
openssl genrsa -aes256 -out private.key 8912
```

* To generate a public key we use our previously generated private key:

```
openssl rsa -in private.key -pubout -out public.key
```

* Lets now encrypt a file (plaintext.txt) using our public key:

```
openssl rsautl -encrypt -pubin -inkey public.key -in plaintext.txt -out encrypted.txt
```

* Now, if we use our private key, we can decrypt the file and get the original message:

```
openssl rsautl -decrypt -inkey private.key -in encrypted.txt -out plaintext.txt
```