Decrypt a JWE into BinData

See more JSON Web Encryption (JWE) Examples

Demonstrates Jwe.DecryptBd, which decrypts a recipient of a loaded JWE and writes the plaintext bytes into a BinData.

#import <CkoJwe.h>
#import <NSString.h>
#import <CkoBinData.h>

BOOL success = NO;

CkoJwe *jwe = [[CkoJwe alloc] init];

//  Load the JWE compact serialization to be decrypted.
NSString *jweCompact = @"eyJhbGciOiJBMjU2S1ciLCJlbmMiOiJBMjU2R0NNIn0.<...>.<iv>.<ciphertext>.<tag>";
success = [jwe LoadJwe: jweCompact];
if (success == NO) {
    NSLog(@"%@",jwe.LastErrorText);
    return;
}

//  The 256-bit key-wrapping key (base64) for recipient index 0.  In production, obtain the key
//  from a secure source rather than hard-coding it.
NSString *base64Key = @"YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXowMTIzNDU=";
success = [jwe SetWrappingKey: [NSNumber numberWithInt: 0] encodedKey: base64Key encoding: @"base64"];
if (success == NO) {
    NSLog(@"%@",jwe.LastErrorText);
    return;
}

//  Decrypt recipient index 0, writing the plaintext bytes into a BinData.
CkoBinData *bd = [[CkoBinData alloc] init];
success = [jwe DecryptBd: [NSNumber numberWithInt: 0] bd: bd];
if (success == NO) {
    NSLog(@"%@",jwe.LastErrorText);
    return;
}

NSLog(@"%@%d%@",@"Decrypted ",[bd.NumBytes intValue],@" bytes.");