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PHP Extension

openssl smime -encrypt -des3 -in <file> <pem file>

See more OpenSSL Examples

OpenSSL SMIME encrypt file using PEM containing a certificate.

Chilkat PHP Extension Downloads

PHP Extension
<?php

include("chilkat.php");

$success = false;

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

// Load the cert from a PEM file.

$pem = new CkPem();
// Our particular PEM was not encrypted, so we pass an empty password.
// Also, a private key is not needed for encryption.  The PEM used to test this example
// happens to have a private key, but it's not actually used.
$success = $pem->LoadPemFile('qa_data/openssl/rsaCertAndKey.pem','');
if ($success == false) {
    print $pem->lastErrorText() . "\n";
    exit;
}

if ($pem->get_NumCerts() == 0) {
    print 'PEM does not contain any certificates.' . "\n";
    exit;
}

// cert is a CkCert
$cert = $pem->GetCert(0);
if ($pem->get_LastMethodSuccess() == false) {
    print $pem->lastErrorText() . "\n";
    exit;
}

// -------------------------------------------------------------------------------------
// Duplicate this OpenSSL command:   openssl smime -encrypt -des3 -in <file> <pem file>
// -------------------------------------------------------------------------------------
$crypt = new CkCrypt2();
$success = $crypt->SetEncryptCert($cert);
if ($success == false) {
    print $crypt->lastErrorText() . "\n";

    exit;
}

$crypt->put_CryptAlgorithm('PKI');
$crypt->put_Pkcs7CryptAlg('3des');
$crypt->put_KeyLength(168);

// Load the file to be encrypted.
$bd = new CkBinData();
$success = $bd->LoadFile('qa_data/openssl/hello.txt');
if ($success == false) {
    print 'Failed to load the input file.' . "\n";
    exit;
}

// Encrypt.
$success = $crypt->EncryptBd($bd);
if ($success == false) {
    print $crypt->lastErrorText() . "\n";
    exit;
}

// The openssl smime -encrypt command produces encrypte MIME such as this:

// MIME-Version: 1.0
// Content-Disposition: attachment; filename="smime.p7m"
// Content-Type: application/x-pkcs7-mime; smime-type=enveloped-data; name="smime.p7m"
// Content-Transfer-Encoding: base64
// 
// MIICzwYJKoZIhvcNAQcDoIICwDCCArwCAQAxggF8MIIBeAIBADBgMEoxCzAJBgNVBAYTAlVTMRYw
// FAYDVQQKEw1MZXQncyBFbmNyeXB0MSMwIQYDVQQDExpMZXQncyBFbmNyeXB0IEF1dGhvcml0eSBY
// MwISA9Nqgb1dH/XTDNeKzN1nR85iMA0GCSqGSIb3DQEBAQUABIIBAIQqPexjxWovgxwKV/r3HL/U
// EP9Yozvz5hBeX5VvRZjKSi4FRw5wapElPK+4FB82hiAR9Mi3c16PvPSVkJv3l78Mv5uaaOs/OmUz
// mIHFB6Z+l2E52BDmUVWJZTQ09vdWy6+NIRlg2R9Z1NkmZ4BZCJk6mHB/Yx03IaOxK8LnwieDMthM
// SvxbhJnIOISN7k7ofs+/0vTXUpdQ+tlmwyVySMGQ6VMk+z4sqZJ2stacqCPtt/aiSwJ9p0OKmihf
// 3KDJceXJtavIQeA97yz1LqPvle35mmd5sBhV9qQYdTV/KJ+YM5uEZ9BHYbvMJbADFHwKzhcEY3qA
// 7T9acmEsb7NycOIwggE1BgkqhkiG9w0BBwEwFAYIKoZIhvcNAwcECERX/ZoHweSkgIIBEMmCMx49
// zjVAnGqRaBbvzQT1hg0uQSxIJjxMxC+HSuM+eY9oSOsbrw4uIijHKH9NdOpeDsdRzg2z5EBM7AlP
// Ht9DyPW5C2deV6RPX4F8gyExz+JUXrd+3Yb3AKTdpDkTWDmNCeO0r/YSqp518+mfU5hG8e336u51
// HAM44FeknA8oThWsD/wUB1e8vzsatK4UXW/KSu/166V7z+VT86kd+IHa7t60U9Yp0ZXgcM5Pb5Ni
// 69Qc5MKPzom2801H5UR/WjCgsxOIjOj49sKisjRy79skrJzxY5ZG05T0dKn6KC3TjRpIEEeOyhCd
// Nm2Y7dcW8GLMepdhWay5vePmQxmvmhbAtBprIem14NcrYeG6D5wP

// We have the body in bd
// Construct the header and base64 body...
$sbEncryptedMime = new CkStringBuilder();

$sbEncryptedMime->AppendLine('MIME-Version: 1.0',true);
$sbEncryptedMime->AppendLine('Content-Disposition: attachment; filename=\'smime.p7m\'',true);
$sbEncryptedMime->AppendLine('Content-Type: application/x-pkcs7-mime; smime-type=enveloped-data; name=\'smime.p7m\'',true);
$sbEncryptedMime->AppendLine('Content-Transfer-Encoding: base64',true);
$sbEncryptedMime->AppendLine('',true);
$sbEncryptedMime->AppendLine($bd->getEncoded('base64_mime'),true);

// Show the result.
print $sbEncryptedMime->getAsString() . "\n";

// or save to a file..
$success = $sbEncryptedMime->WriteFile('qa_output/encryptedMime.txt','utf-8',false);

?>