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Objective-C

Send Signed Email using PFX File (long version)

Demonstrates how to send a signed email using a digital certificate w/ private key stored in a PFX file.

Chilkat Objective-C Downloads

Objective-C
#import <CkoMailMan.h>
#import <CkoEmail.h>
#import <CkoCertStore.h>
#import <CkoJsonObject.h>
#import <CkoCert.h>

BOOL success = NO;

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

// The mailman object is used for sending and receiving email.
CkoMailMan *mailman = [[CkoMailMan alloc] init];

// Set the SMTP server.
mailman.SmtpHost = @"smtp.mymailserver.com";

// Create a new email object
CkoEmail *email = [[CkoEmail alloc] init];

email.Subject = @"This email is signed";
email.Body = @"This is a digitally signed mail";
email.From = @"Chilkat Admin <admin@chilkatsoft.com>";
success = [email AddTo: @"Chilkat Support" emailAddress: @"support@chilkatsoft.com"];

// Indicate that the email should be sent signed.
email.SendSigned = YES;

// Load a PFX file into a certificate store object.
// Then locate the certificate matching the  sender's email address,
// and use it for signing.
// (a PFX file may contain more than one certificate.)
CkoCertStore *certStore = [[CkoCertStore alloc] init];
// The 1st argument is the path of the PFX file, the 2nd arg is the 
// PFX file's password:
success = [certStore LoadPfxFile: @"/pfx_files/chilkatsoft_secret.pfx" password: @"secret"];
if (success != YES) {
    NSLog(@"%@",certStore.LastErrorText);
    return;
}

// Find the certificate for the email address:
CkoJsonObject *jsonE = [[CkoJsonObject alloc] init];
[jsonE UpdateString: @"email" value: @"admin@chilkatsoft.com"];

CkoCert *cert = [[CkoCert alloc] init];
success = [certStore FindCert: jsonE cert: cert];
if (success == NO) {
    NSLog(@"%@",certStore.LastErrorText);
    return;
}

// Alternatively, if a PFX file is known to contain a single certificate,
// you may load it directly into a Chilkat certificate object.
// This snippet of source code shows how:
CkoCert *cert2 = [[CkoCert alloc] init];
// The 1st argument is the filename, the 2nd arg is the 
// PFX file's password:
success = [cert2 LoadPfxFile: @"/pfx_files/chilkatsoft_secret.pfx" password: @"secret"];
if (success != YES) {
    NSLog(@"%@",cert2.LastErrorText);
    return;
}

// This example will use the cert from the certStore...
success = [email SetSigningCert: cert];

// Signed email can be sent in two different ways.  
// In a multipart/signed email, the signature is attached as a separate MIME part.
// In an opaque email (signedData) the content of the email is encapsulated within the signature
// and the email is sent as "application/pkcs7-mime". 
// Either should be fine, but some receiving systems might require one or the other..
mailman.OpaqueSigning = NO;

// Send a signed email.
success = [mailman SendEmail: email];
if (success != YES) {
    NSLog(@"%@",mailman.LastErrorText);
}
else {
    // The LastErrorText property provides information
    // even when successful.
    NSLog(@"%@",mailman.LastErrorText);
    NSLog(@"%@",@"Mail Sent!");
}