It appears to be a problem* with the key you've provided. Adding die "invalid key" unless $rsa->check_key; causes the script to die. The following works for me:

use warnings;
use strict;
use Crypt::OpenSSL::RSA;
use Crypt::OpenSSL::Bignum;
use Data::Dump;

my $rsa = Crypt::OpenSSL::RSA->generate_key(1024);
my $priv = $rsa->get_private_key_string;
my $ciphertext = $rsa->encrypt("Hello");

my $rsa2 = Crypt::OpenSSL::RSA->new_private_key($priv);
my $plaintext = $rsa2->decrypt($ciphertext);
dd $plaintext;

my %params;
@params{qw/n e d p q/, 'd mod (p-1)', 'd mod (q-1)', '1/q mod p'}
    = map { $_->to_hex } $rsa->get_key_parameters;
dd \%params;

[download]

* Update: Specifically, when I replace your d and n parameters with newly generated ones, your code works for me (as long as both sides use pkcs1_padding or pkcs1_oaep_padding, the latter being the default). Note that $rsa->check_key checks for the presence of the parameters n, e, d, p, and q, you're not giving it p and q (though the decryption still works). If you were to provide Crypt::OpenSSL::RSA with only n and e, that would tell the module it's a public key only. I'm not sure why you're working with keys the way you've shown in your post?

In reply to Re: RSA encrypt but no decrypt. What is the problem? (updated) by haukex
in thread RSA encrypt but no decrypt. What is the problem? by Forb

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