Build MtProtoKit

submodules/MtProtoKit/Sources/MTMessageEncryptionKey.m

@@ -0,0 +1,121 @@
+#import <MtProtoKit/MTMessageEncryptionKey.h>
+
+#import <MtProtoKit/MTEncryption.h>
+
+@implementation MTMessageEncryptionKey
+
++ (instancetype)messageEncryptionKeyForAuthKey:(NSData *)authKey messageKey:(NSData *)messageKey toClient:(bool)toClient
+{
+#ifdef DEBUG
+    NSAssert(authKey != nil, @"authKey should not be nil");
+    NSAssert(messageKey != nil, @"message key should not be nil");
+#endif
+    
+    if (authKey == nil || authKey.length == 0 || messageKey == nil || messageKey.length == 0)
+        return nil;
+
+    int x = toClient ? 8 : 0;
+    
+    NSData *sha1_a = nil;
+    {
+        NSMutableData *data = [[NSMutableData alloc] init];
+        [data appendData:messageKey];
+        [data appendBytes:(((int8_t *)authKey.bytes) + x) length:32];
+        sha1_a = MTSha1(data);
+    }
+    
+    NSData *sha1_b = nil;
+    {
+        NSMutableData *data = [[NSMutableData alloc] init];
+        [data appendBytes:(((int8_t *)authKey.bytes) + 32 + x) length:16];
+        [data appendData:messageKey];
+        [data appendBytes:(((int8_t *)authKey.bytes) + 48 + x) length:16];
+        sha1_b = MTSha1(data);
+    }
+    
+    NSData *sha1_c = nil;
+    {
+        NSMutableData *data = [[NSMutableData alloc] init];
+        [data appendBytes:(((int8_t *)authKey.bytes) + 64 + x) length:32];
+        [data appendData:messageKey];
+        sha1_c = MTSha1(data);
+    }
+    
+    NSData *sha1_d = nil;
+    {
+        NSMutableData *data = [[NSMutableData alloc] init];
+        [data appendData:messageKey];
+        [data appendBytes:(((int8_t *)authKey.bytes) + 96 + x) length:32];
+        sha1_d = MTSha1(data);
+    }
+    
+    NSMutableData *aesKey = [[NSMutableData alloc] init];
+    [aesKey appendBytes:(((int8_t *)sha1_a.bytes)) length:8];
+    [aesKey appendBytes:(((int8_t *)sha1_b.bytes) + 8) length:12];
+    [aesKey appendBytes:(((int8_t *)sha1_c.bytes) + 4) length:12];
+    
+    NSMutableData *aesIv = [[NSMutableData alloc] init];
+    [aesIv appendBytes:(((int8_t *)sha1_a.bytes) + 8) length:12];
+    [aesIv appendBytes:(((int8_t *)sha1_b.bytes)) length:8];
+    [aesIv appendBytes:(((int8_t *)sha1_c.bytes) + 16) length:4];
+    [aesIv appendBytes:(((int8_t *)sha1_d.bytes)) length:8];
+    
+    MTMessageEncryptionKey *result = [[MTMessageEncryptionKey alloc] init];
+    result->_key = [[NSData alloc] initWithData:aesKey];
+    result->_iv = [[NSData alloc] initWithData:aesIv];
+    
+    return result;
+}
+
++ (instancetype)messageEncryptionKeyV2ForAuthKey:(NSData *)authKey messageKey:(NSData *)messageKey toClient:(bool)toClient {
+#ifdef DEBUG
+    NSAssert(authKey != nil, @"authKey should not be nil");
+    NSAssert(messageKey != nil, @"message key should not be nil");
+#endif
+    
+    if (authKey == nil || authKey.length == 0 || messageKey == nil || messageKey.length == 0)
+        return nil;
+    
+    int xValue = toClient ? 8 : 0;
+    
+    NSMutableData *sha256_a_data = [[NSMutableData alloc] init];
+    [sha256_a_data appendData:messageKey];
+    [sha256_a_data appendBytes:authKey.bytes + xValue length:36];
+    
+    NSData *sha256_a = MTSha256(sha256_a_data);
+    
+    NSMutableData *sha256_b_data = [[NSMutableData alloc] init];
+    [sha256_b_data appendBytes:authKey.bytes + 40 + xValue length:36];
+    [sha256_b_data appendData:messageKey];
+    
+    NSData *sha256_b = MTSha256(sha256_b_data);
+    
+    NSMutableData *aesKey = [[NSMutableData alloc] init];
+    [aesKey appendBytes:sha256_a.bytes + 0 length:8];
+    [aesKey appendBytes:sha256_b.bytes + 8 length:16];
+    [aesKey appendBytes:sha256_a.bytes + 24 length:8];
+    
+    NSMutableData *aesIv = [[NSMutableData alloc] init];
+    [aesIv appendBytes:sha256_b.bytes + 0 length:8];
+    [aesIv appendBytes:sha256_a.bytes + 8 length:16];
+    [aesIv appendBytes:sha256_b.bytes + 24 length:8];
+    
+    MTMessageEncryptionKey *result = [[MTMessageEncryptionKey alloc] init];
+    result->_key = [[NSData alloc] initWithData:aesKey];
+    result->_iv = [[NSData alloc] initWithData:aesIv];
+    
+    return result;
+}
+
+- (instancetype)initWithKey:(NSData *)key iv:(NSData *)iv
+{
+    self = [super init];
+    if (self != nil)
+    {
+        _key = key;
+        _iv = iv;
+    }
+    return self;
+}
+
+@end