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Perl

Duplicate openssl dgst -md5 -sign myKey.pem something.txt | openssl enc -base64 -A

See more RSA Examples

Demonstrates how to duplicate the creation of an RSA signature produced by this OpenSSL command:
openssl dgst -md5 -sign myKey.pem something.txt | openssl enc -base64 -A

Chilkat Perl Downloads

Perl
use chilkat();

$success = 0;

# This example assumes the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

$pkey = chilkat::CkPrivateKey->new();

# Load the private key from an RSA PEM file:
$success = $pkey->LoadPemFile("myKey.pem");

$rsa = chilkat::CkRsa->new();

# Import the private key into the RSA component:
$success = $rsa->UsePrivateKey($pkey);
if ($success == 0) {
    print $rsa->lastErrorText() . "\r\n";
    exit;
}

# OpenSSL uses BigEndian byte ordering:
$rsa->put_LittleEndian(0);

# The resulting signature will be a Base64 string:
$rsa->put_EncodingMode("base64");

# For simplicity, we're not loading
# the data to be signed from a file.  We are instead simply
# using a literal string value.  
$strData = "This is the text to be signed.";

# Hash the input using MD5, and then sign the hash:
# Other valid hash algorithm choices are "md2" and "sha-1".
$base64Sig = $rsa->signStringENC($strData,"md5");

print $base64Sig . "\r\n";

print "Success!" . "\r\n";