Objective-C

Duplicate OpensSSL to Create Signature using Cert and Key Files

See more OpenSSL Examples

This example duplicates the following:

openssl smime –sign -in something.xml -out something.der -signer mycert.crt -inkey cert.key -outform der –nodetach

Note: Although "smime" is the OpenSSL command, it's not actually producing S/MIME. The arguments "-outform der -binary" indicates that the output is binary DER (i.e. the PKCS7 binary signature). The input can be any type of file: XML, PDF, JPG, ... *anything*...

Objective-C

#import <CkoCrypt2.h>
#import <CkoCert.h>
#import <CkoBinData.h>
#import <CkoPrivateKey.h>

BOOL success = NO;

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

CkoCrypt2 *crypt = [[CkoCrypt2 alloc] init];

// Load the cert and private key from separate files.
CkoCert *cert = [[CkoCert alloc] init];
success = [cert LoadFromFile: @"myCert.crt"];
if (success != YES) {
    NSLog(@"%@",cert.LastErrorText);
    return;
}

CkoBinData *bd = [[CkoBinData alloc] init];
success = [bd LoadFile: @"cert.key"];
CkoPrivateKey *privkey = [[CkoPrivateKey alloc] init];
// Load from any format private key.
// If the file does not need a password, the 2nd arg is ignored.
success = [privkey LoadAnyFormat: bd password: @"password_if_needed"];
if (success != YES) {
    NSLog(@"%@",privkey.LastErrorText);
    return;
}

success = [crypt SetSigningCert2: cert key: privkey];
if (success != YES) {
    NSLog(@"%@",crypt.LastErrorText);
    return;
}

// Create the opaque signature (PKCS7 binary DER that contains both the signature and original file data).
success = [crypt CreateP7M: @"qa_data/infile.anything" p7mPath: @"qa_output/outfile.der"];
if (success != YES) {
    NSLog(@"%@",crypt.LastErrorText);
    return;
}

NSLog(@"%@",@"Success.");