session-ios/SignalServiceKit/src/Util/Cryptography.h

105 lines
3.6 KiB
Objective-C
Executable File

//
// Copyright (c) 2018 Open Whisper Systems. All rights reserved.
//
NS_ASSUME_NONNULL_BEGIN
extern const NSUInteger kAES256_KeyByteLength;
/// Key appropriate for use in AES256-GCM
@interface OWSAES256Key : NSObject <NSSecureCoding>
/// Generates new secure random key
- (instancetype)init;
+ (instancetype)generateRandomKey;
/**
* @param data representing the raw key bytes
*
* @returns a new instance if key is of appropriate length for AES256-GCM
* else returns nil.
*/
+ (nullable instancetype)keyWithData:(NSData *)data;
/// The raw key material
@property (nonatomic, readonly) NSData *keyData;
@end
#pragma mark -
@interface AES25GCMEncryptionResult : NSObject
@property (nonatomic, readonly) NSData *ciphertext;
@property (nonatomic, readonly) NSData *initializationVector;
@property (nonatomic, readonly) NSData *authTag;
- (instancetype)init NS_UNAVAILABLE;
- (nullable instancetype)initWithCipherText:(NSData *)cipherText
initializationVector:(NSData *)initializationVector
authTag:(NSData *)authTag NS_DESIGNATED_INITIALIZER;
@end
#pragma mark -
@interface Cryptography : NSObject
typedef NS_ENUM(NSInteger, TSMACType) {
TSHMACSHA256Truncated10Bytes = 2,
TSHMACSHA256AttachementType = 3
};
+ (NSData *)generateRandomBytes:(NSUInteger)numberBytes;
+ (uint32_t)randomUInt32;
+ (uint64_t)randomUInt64;
+ (unsigned)randomUnsigned;
#pragma mark - SHA and HMAC methods
// Full length SHA256 digest for `data`
+ (nullable NSData *)computeSHA256Digest:(NSData *)data;
// Truncated SHA256 digest for `data`
+ (nullable NSData *)computeSHA256Digest:(NSData *)data truncatedToBytes:(NSUInteger)truncatedBytes;
+ (nullable NSString *)truncatedSHA1Base64EncodedWithoutPadding:(NSString *)string;
+ (nullable NSData *)decryptAppleMessagePayload:(NSData *)payload withSignalingKey:(NSString *)signalingKeyString;
+ (nullable NSData *)computeSHA256HMAC:(NSData *)data withHMACKey:(NSData *)HMACKey;
#pragma mark encrypt and decrypt attachment data
// Though digest can and will be nil for legacy clients, we now reject attachments lacking a digest.
+ (nullable NSData *)decryptAttachment:(NSData *)dataToDecrypt
withKey:(NSData *)key
digest:(nullable NSData *)digest
unpaddedSize:(UInt32)unpaddedSize
error:(NSError **)error;
+ (nullable NSData *)encryptAttachmentData:(NSData *)attachmentData
outKey:(NSData *_Nonnull *_Nullable)outKey
outDigest:(NSData *_Nonnull *_Nullable)outDigest;
+ (nullable AES25GCMEncryptionResult *)encryptAESGCMWithData:(NSData *)plaintext
additionalAuthenticatedData:(nullable NSData *)additionalAuthenticatedData
key:(OWSAES256Key *)key
NS_SWIFT_NAME(encryptAESGCM(plainTextData:additionalAuthenticatedData:key:));
+ (nullable NSData *)decryptAESGCMWithInitializationVector:(NSData *)initializationVector
ciphertext:(NSData *)ciphertext
additionalAuthenticatedData:(nullable NSData *)additionalAuthenticatedData
authTag:(NSData *)authTagFromEncrypt
key:(OWSAES256Key *)key;
+ (nullable NSData *)encryptAESGCMWithProfileData:(NSData *)plaintextData key:(OWSAES256Key *)key;
+ (nullable NSData *)decryptAESGCMWithProfileData:(NSData *)encryptedData key:(OWSAES256Key *)key;
+ (void)seedRandom;
@end
NS_ASSUME_NONNULL_END