Objective-C

RSA Encrypt RSA/ECB/OAEPWithSHA1AndMGF1Padding

See more RSA Examples

Demonstrates how to RSA encrypt using RSA/ECB/OAEPWithSHA1AndMGF1Padding. Also demonstrates RSA/ECB/OAEPWithSHA-256AndMGF1Padding. Both of these terms are from Java's JCE. Note: In this context, "ECB" doesn't actually mean anything. It's a symmetric cipher mode that doesn't apply (or make sense) in this context. Objective-C

#import <CkoRsa.h>
#import <CkoPublicKey.h>
#import <NSString.h>
#import <CkoPrivateKey.h>

BOOL success = NO;

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

CkoRsa *rsa = [[CkoRsa alloc] init];

//  First load a public key object with a public key.
//  In this case, we'll load it from a file.
CkoPublicKey *pubkey = [[CkoPublicKey alloc] init];
success = [pubkey LoadFromFile: @"qa_data/pem/rsa_public.pem"];
if (success == NO) {
    NSLog(@"%@",pubkey.LastErrorText);
    return;
}

//  RSA encryption is limited to small amounts of data. The limit
//  is typically a few hundred bytes and is based on the key size and
//  padding (OAEP vs. PKCS1_5).  RSA encryption is typically used for
//  encrypting hashes or symmetric (bulk encryption algorithm) secret keys.
NSString *plainText = @"Time is an illusion. Lunchtime doubly so.";

//  Import the public key to be used for encrypting.
success = [rsa UsePublicKey: pubkey];

//  To get OAEP padding, set the PkcsPadding property equal to false
rsa.PkcsPadding = NO;
rsa.OaepHash = @"sha256";

//  Indicate we'll want hex output
rsa.EncodingMode = @"hex";

//  Encrypt..
BOOL usePrivateKey = NO;
NSString *encryptedStr = [rsa EncryptStringENC: plainText bUsePrivateKey: usePrivateKey];
NSLog(@"%@",encryptedStr);

//  -------------------------------------------------
//  Now decrypt with the matching private key.
CkoRsa *rsa2 = [[CkoRsa alloc] init];

CkoPrivateKey *privKey = [[CkoPrivateKey alloc] init];
success = [privKey LoadEncryptedPem: @"qa_data/pem/rsa_passwd.pem" password: @"passwd"];
if (success == NO) {
    NSLog(@"%@",privKey.LastErrorText);
    return;
}

success = [rsa2 UsePrivateKey: privKey];

//  Make sure we have the same settings used for encryption.
rsa2.PkcsPadding = NO;
rsa2.EncodingMode = @"hex";
rsa2.OaepHash = @"sha256";

NSString *originalStr = [rsa2 DecryptStringENC: encryptedStr bUsePrivateKey: YES];

NSLog(@"%@",originalStr);