Digests using OpenSSL. Shell and perl editions,

Here's a small snippet that allows one to generate a digest.
Short of it: Perl

my $key_string = read_file("secretkey.pem");
my $key = Crypt::OpenSSL::RSA->new_private_key($key_string);
my $filestring = read_file("somefile");
$key->use_md5_hash();
my $signature = $key->sign($filestring);
print encode_base64($signature)."\n";

Short of it: shell

openssl dgst -md5 -sign secretkey.pem  <  somefile |base64 | tee somefile.sig_from_shell
cat somefile.sig_from_shell | base64 -d > somefile.sig_from_shell.raw
openssl dgst -md5 -verify public.pem  -signature somefile.sig_from_perl.raw <  somefile

In it's goriness:

OpenSSL compatible encryption

I wanted to have a Perl program that encrypted a file using perl's Crypt::CBC and be able to decrypt it using the OpenSSL enc application. It took me awhile to figure this one out.

my $cipher = Crypt::CBC->new(
-key => "123",
-cipher => 'Blowfish',
-keysize => 128/8,
-header => 'salt'
);

This works with

openssl enc -bf-cbc -d -in /tmp/staging/passwd.gz.enc -out ah -pass pass:123

The same applies for other ciphers e.g

my $cipher = Crypt::CBC->new(
-key => "123",
-cipher => 'Rijndael',
-keysize => 128/8,
-header => 'salt'
);

This works with

openssl enc -aes-128-cbc -d -in /tmp/staging/passwd.gz.enc -out ah -pass pass:123

Inspiration from stackoverflow