Decrypt P7M using PFX to get MIME

Demonstrates how to decrypt a .p7m (PKCS7) binary file using a certificate and private key from a PFX file. The result of the decryption (in this case) is MIME text that may be loaded into a Chilkat MIME object.

Note: Any type of file or data may be encrypted to produce a .p7m (PKCS7) encrypted file. This example was prompted by a customer needing to decrypt a MIME message. The final step of loading the decrypted text into a MIME object would be skipped if decrypting something other than MIME..

Download Chilkat Crypt ActiveX

Download Chilkat MIME ActiveX

<?php


$crypt = new COM("Chilkat.Crypt2");

//  Any string argument automatically begins the 30-day trial.
$success = $crypt->UnlockComponent('30-day trial');
if ($success != true) {
    print $crypt->lastErrorText() . "\n";
    exit;
}

//  Read the P7M file into memory.
$p7mData = $crypt->ReadFile('encrypted.p7m');

//  Setup the crypt object:

//  Indicate that public-key decryption is to be used.
$crypt->CryptAlgorithm = 'pki';

//  Add a PFX file to allow the crypt object to find
//  the certificate and private key needed for decryption
$pfxFilePath = 'myPfx.pfx';
$pfxPassword = 'secret';
$success = $crypt->AddPfxSourceFile($pfxFilePath,$pfxPassword);
if ($success != true) {
    print $crypt->lastErrorText() . "\n";
    exit;
}

//  Assuming the decrypted data will be text, decrypt to
//  a string.
$mimeText = $crypt->decryptString($p7mData);
if (is_null($mimeText)) {
    print $crypt->lastErrorText() . "\n";
    exit;
}

//  Note: Chilkat Crypt and Chilkat MIME are separate products.
//  To use both objects, one would license the "Chilkat Bundle",
//  which provides licenses to all existing Chilkat products.
//  This is less expensive than licensing each of the two products separately.

$mime = new COM("Chilkat.Mime");

$success = $mime->UnlockComponent('Anyting for 30-day trial');
if ($success != true) {
    print $mime->lastErrorText() . "\n";
    exit;
}

//  Load the MIME text into the MIME object.
$success = $mime->LoadMime($mimeText);
if ($success != true) {
    print $mime->lastErrorText() . "\n";
    exit;
}

//  Save the MIME to a file:
$success = $mime->SaveMime('outMime.txt');
if ($success != true) {
    print $mime->lastErrorText() . "\n";
    exit;
}

//  Success!  Output the MIME text:
print $mime->getMime() . "\n";


?>