MYMockKeys.m

//
//  MYMockKeys.m
//  MYCrypto
//
//  Created by Jens Alfke on 11/25/10.
//  Copyright 2010 Jens Alfke. All rights reserved.
//

#import "MYMockKeys.h"
#import "Test.h"
#import "MYDigest.h"


#if DEBUG


@implementation MYMockKey


@synthesize keyData=_keyData;


- (id) initWithKeyData: (NSData*)keyData {
    Assert(keyData);
    self = [super init];
    if (self != nil) {
        _keyData = [keyData copy];
    }
    return self;
}


- (NSString*) description {
    NSString* keyStr = [[NSString alloc] initWithData: _keyData encoding: NSUTF8StringEncoding];
    return $sprintf(@"%@[%@]", [self class], keyStr);
}


@end



@implementation MYMockPrivateKey


@synthesize publicKey=_publicKey;


+ (MYMockPrivateKey*) createKeyPair {
    return [[MYMockPrivateKey alloc] init];
}


- (id) initWithKeyData: (NSData*)keyData {
    self = [super initWithKeyData:keyData];
    if (self != nil) {
        _publicKey = [[MYMockPublicKey alloc] initWithKeyData:_keyData];
    }
    return self;
}


- (id) init
{
    NSString *key = [NSString stringWithFormat: @"MOCK_%08lX:", random()];
    return [self initWithKeyData: [key dataUsingEncoding:NSUTF8StringEncoding]];
}


- (MYSHA1Digest*) publicKeyDigest {
    return _publicKey.publicKeyDigest;
}


- (NSData*) signData: (NSData*)data {
    Assert(data);
    const RawSHA1Digest *digest = [[MYSHA1Digest digestOfData:data] rawSHA1Digest];
    NSMutableData* result = [NSMutableData dataWithData: _keyData];
    [result appendBytes: digest length: sizeof(*digest)];
    return result;
}


@end




@implementation MYMockPublicKey


- (MYSHA1Digest*) publicKeyDigest {
    return _keyData.my_SHA1Digest;
}


- (BOOL) verifySignature: (NSData*)signature ofData: (NSData*)data {
    Assert(data);
    const RawSHA1Digest *digest = [[MYSHA1Digest digestOfData:data] rawSHA1Digest];
    size_t keyLength = _keyData.length;
    if (signature.length != keyLength + sizeof(*digest))
        return NO;
    if (memcmp(signature.bytes, _keyData.bytes, keyLength) != 0)
        return NO;
    if (memcmp(signature.bytes + keyLength, digest, sizeof(*digest) - keyLength) != 0)
        return NO;
    return YES;
}


@end




TestCase(MYMockPrivateKey) {
    MYMockPrivateKey* privateKey = [MYMockPrivateKey createKeyPair];
    MYMockPublicKey* publicKey = privateKey.publicKey;
    Log(@"privateKey = %@; publicKey = %@", privateKey, publicKey);
    NSData *pubKeyData = publicKey.keyData;
    CAssertEq(pubKeyData.length, 14u);
    CAssertEqual(privateKey.keyData, pubKeyData);
    
    MYSHA1Digest *pubKeyDigest = publicKey.publicKeyDigest;
    Log(@"Public key digest = %@",pubKeyDigest);
    CAssertEqual(privateKey.publicKeyDigest, pubKeyDigest);
    
    // Let's sign data:
    NSData *data = [@"This is a test. This is only a test!" dataUsingEncoding: NSUTF8StringEncoding];
    NSData *sig = [privateKey signData: data];
    Log(@"Signature = %@ (%lu bytes)",sig,sig.length);
    CAssert(sig);
    CAssert( [publicKey verifySignature: sig ofData: data] );    

    // Test creating a public key from data:
    Log(@"Reconstituting public key from data...");
    MYMockPublicKey* pub = [[MYMockPublicKey alloc] initWithKeyData: pubKeyData];
    CAssert(pub);
    CAssertEqual(pub.keyData, pubKeyData);
    CAssertEqual(pub.publicKeyDigest, pubKeyDigest);
    CAssert( [pub verifySignature: sig ofData: data] );
    Log(@"Verified signature from reconstituted key.");
}

#endif //DEBUG



/*
 Copyright (c) 2010, Jens Alfke <jens@mooseyard.com>. All rights reserved.
 
 Redistribution and use in source and binary forms, with or without modification, are permitted
 provided that the following conditions are met:
 
 * Redistributions of source code must retain the above copyright notice, this list of conditions
 and the following disclaimer.
 * Redistributions in binary form must reproduce the above copyright notice, this list of conditions
 and the following disclaimer in the documentation and/or other materials provided with the
 distribution.
 
 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR
 IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 
 FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRI-
 BUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 
  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 
 THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */