I’ve been automating a login that encrypts the password on the client with the WebCrypto API before it is sent out.

Specifically, it’s using RSA-OAEP and basically follows the examples from the MDN github:

let key = window.crypto.subtle.importKey(
    "spki", binaryDer,
    { name: "RSA-OAEP", hash: "SHA-256" },
    true, ["encrypt"]
);

let ciphertext = window.crypto.subtle.encrypt(
    { name: "RSA-OAEP" },
    key, cleartext
);

I would have liked to do this in perl, but Crypt::OpenSSL::RSA only supports

EME-OAEP padding as defined in PKCS #1 v2.0 with SHA-1, MGF1

…and I neither see a way to change the hash function for the padding, nor did I find another module for the job.

So I had to resort to calling the openssl binary and encrypt the password like so:

openssl pkeyutl -in cleartext.txt -encrypt -pubin -inkey key.pem 
    -pkeyopt rsa_padding_mode:oaep -pkeyopt rsa_oaep_md:sha256 
    -pkeyopt rsa_mgf1_md:sha256

This works, however I was wondering if there is a way to achieve this with perl only.