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Objective-C

Duplicate openssl smime -encrypt -binary -aes-256-cbc -in some_file.dat -out some_file.dat.enc -outform DER cert.crt

See more OpenSSL Examples

Demonstrates how to encrypt to binary DER using 256-bit AES (CBC mode) as the underlying symmetric encryption algorithm, to produce PKCS7 enveloped data (binary DER).

Duplicates the following openssl command:

openssl smime -encrypt -binary -aes-256-cbc -in some_file.dat -out some_file.dat.enc -outform DER cert.crt

Chilkat Objective-C Downloads

Objective-C
#import <CkoCert.h>
#import <CkoBinData.h>
#import <CkoCrypt2.h>

BOOL success = NO;

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

CkoCert *cert = [[CkoCert alloc] init];
success = [cert LoadFromFile: @"qa_data/openssl/EE.cer"];
if (success == NO) {
    NSLog(@"%@",cert.LastErrorText);
    return;
}

CkoBinData *bd = [[CkoBinData alloc] init];
success = [bd LoadFile: @"qa_data/openssl/hello.txt"];
// Assuming success..

CkoCrypt2 *crypt = [[CkoCrypt2 alloc] init];
success = [crypt SetEncryptCert: cert];
if (success == NO) {
    NSLog(@"%@",crypt.LastErrorText);
    return;
}

crypt.CryptAlgorithm = @"PKI";

// Indicate the underlying symmetric encryption to be used:
crypt.Pkcs7CryptAlg = @"aes";
crypt.KeyLength = [NSNumber numberWithInt:256];
crypt.CipherMode = @"cbc";

success = [crypt CkEncryptFile: @"qa_data/openssl/hello.txt" destFile: @"qa_output/hello.txt.enc"];
if (success == NO) {
    NSLog(@"%@",crypt.LastErrorText);
    return;
}

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