session-ios/SessionProtocolKit/Signal/Utility/SerializationUtilities.m

82 lines
2.9 KiB
Objective-C

//
// Copyright (c) 2018 Open Whisper Systems. All rights reserved.
//
#import "SerializationUtilities.h"
#import <CommonCrypto/CommonCrypto.h>
#import <SessionProtocolKit/OWSAsserts.h>
NS_ASSUME_NONNULL_BEGIN
@implementation SerializationUtilities
+ (int)highBitsToIntFromByte:(Byte)byte
{
return (byte & 0xFF) >> 4;
}
+ (int)lowBitsToIntFromByte:(Byte)byte
{
return (byte & 0xF);
}
+ (Byte)intsToByteHigh:(int)highValue low:(int)lowValue
{
return (Byte)((highValue << 4 | lowValue) & 0xFF);
}
+ (NSData *)throws_macWithVersion:(int)version
identityKey:(NSData *)senderIdentityKey
receiverIdentityKey:(NSData *)receiverIdentityKey
macKey:(NSData *)macKey
serialized:(NSData *)serialized
{
if (!macKey) {
@throw [NSException exceptionWithName:NSInvalidArgumentException reason:@"Missing macKey." userInfo:nil];
}
if (macKey.length >= SIZE_MAX) {
@throw [NSException exceptionWithName:NSInvalidArgumentException reason:@"Oversize macKey." userInfo:nil];
}
if (!senderIdentityKey) {
@throw
[NSException exceptionWithName:NSInvalidArgumentException reason:@"Missing senderIdentityKey" userInfo:nil];
}
if (senderIdentityKey.length >= SIZE_MAX) {
@throw [NSException exceptionWithName:NSInvalidArgumentException
reason:@"Oversize senderIdentityKey"
userInfo:nil];
}
if (!receiverIdentityKey) {
@throw [NSException exceptionWithName:NSInvalidArgumentException
reason:@"Missing receiverIdentityKey"
userInfo:nil];
}
if (receiverIdentityKey.length >= SIZE_MAX) {
@throw [NSException exceptionWithName:NSInvalidArgumentException
reason:@"Oversize receiverIdentityKey"
userInfo:nil];
}
if (!serialized) {
@throw [NSException exceptionWithName:NSInvalidArgumentException reason:@"Missing serialized." userInfo:nil];
}
if (serialized.length >= SIZE_MAX) {
@throw [NSException exceptionWithName:NSInvalidArgumentException reason:@"Oversize serialized." userInfo:nil];
}
NSMutableData *_Nullable bufferData = [NSMutableData dataWithLength:CC_SHA256_DIGEST_LENGTH];
OWSAssert(bufferData);
CCHmacContext context;
CCHmacInit(&context, kCCHmacAlgSHA256, [macKey bytes], [macKey length]);
CCHmacUpdate(&context, [senderIdentityKey bytes], [senderIdentityKey length]);
CCHmacUpdate(&context, [receiverIdentityKey bytes], [receiverIdentityKey length]);
CCHmacUpdate(&context, [serialized bytes], [serialized length]);
CCHmacFinal(&context, bufferData.mutableBytes);
return [bufferData subdataWithRange:NSMakeRange(0, MAC_LENGTH)];
}
@end
NS_ASSUME_NONNULL_END