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Diffstat (limited to 'xcode/OLMKit/OLMInboundGroupSession.m')
| -rw-r--r-- | xcode/OLMKit/OLMInboundGroupSession.m | 244 |
1 files changed, 244 insertions, 0 deletions
diff --git a/xcode/OLMKit/OLMInboundGroupSession.m b/xcode/OLMKit/OLMInboundGroupSession.m new file mode 100644 index 0000000..6ef51c3 --- /dev/null +++ b/xcode/OLMKit/OLMInboundGroupSession.m @@ -0,0 +1,244 @@ +/* + Copyright 2016 OpenMarket Ltd + Copyright 2016 Vector Creations Ltd + + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. + */ + +#import "OLMInboundGroupSession.h" + +#import "OLMUtility.h" +#include "olm/olm.h" + +@interface OLMInboundGroupSession () +{ + OlmInboundGroupSession *session; +} +@end + + +@implementation OLMInboundGroupSession + +- (void)dealloc { + olm_clear_inbound_group_session(session); + free(session); +} + +- (instancetype)init { + self = [super init]; + if (self) + { + session = malloc(olm_inbound_group_session_size()); + if (session) { + session = olm_inbound_group_session(session); + } + + if (!session) { + return nil; + } + } + return self; +} + +- (instancetype)initInboundGroupSessionWithSessionKey:(NSString *)sessionKey error:(NSError**)error { + self = [self init]; + if (self) { + NSData *sessionKeyData = [sessionKey dataUsingEncoding:NSUTF8StringEncoding]; + size_t result = olm_init_inbound_group_session(session, sessionKeyData.bytes, sessionKeyData.length); + if (result == olm_error()) { + const char *olm_error = olm_inbound_group_session_last_error(session); + + NSString *errorString = [NSString stringWithUTF8String:olm_error]; + NSLog(@"olm_init_inbound_group_session error: %@", errorString); + + if (error && olm_error && errorString) { + *error = [NSError errorWithDomain:OLMErrorDomain + code:0 + userInfo:@{ + NSLocalizedDescriptionKey: errorString, + NSLocalizedFailureReasonErrorKey: [NSString stringWithFormat:@"olm_init_inbound_group_session error: %@", errorString] + }]; + } + + return nil; + } + } + return self; +} + +- (NSString *)sessionIdentifier { + size_t length = olm_inbound_group_session_id_length(session); + NSMutableData *idData = [NSMutableData dataWithLength:length]; + if (!idData) { + return nil; + } + size_t result = olm_inbound_group_session_id(session, idData.mutableBytes, idData.length); + if (result == olm_error()) { + const char *error = olm_inbound_group_session_last_error(session); + NSLog(@"olm_inbound_group_session_id error: %s", error); + return nil; + } + NSString *idString = [[NSString alloc] initWithData:idData encoding:NSUTF8StringEncoding]; + return idString; +} + +- (NSString *)decryptMessage:(NSString *)message messageIndex:(NSUInteger*)messageIndex error:(NSError**)error +{ + NSParameterAssert(message != nil); + NSData *messageData = [message dataUsingEncoding:NSUTF8StringEncoding]; + if (!messageData) { + return nil; + } + NSMutableData *mutMessage = messageData.mutableCopy; + size_t maxPlaintextLength = olm_group_decrypt_max_plaintext_length(session, mutMessage.mutableBytes, mutMessage.length); + if (maxPlaintextLength == olm_error()) { + const char *olm_error = olm_inbound_group_session_last_error(session); + + NSString *errorString = [NSString stringWithUTF8String:olm_error]; + NSLog(@"olm_group_decrypt_max_plaintext_length error: %@", errorString); + + if (error && olm_error && errorString) { + *error = [NSError errorWithDomain:OLMErrorDomain + code:0 + userInfo:@{ + NSLocalizedDescriptionKey: errorString, + NSLocalizedFailureReasonErrorKey: [NSString stringWithFormat:@"olm_group_decrypt_max_plaintext_length error: %@", errorString] + }]; + } + + return nil; + } + // message buffer is destroyed by olm_group_decrypt_max_plaintext_length + mutMessage = messageData.mutableCopy; + NSMutableData *plaintextData = [NSMutableData dataWithLength:maxPlaintextLength]; + + uint32_t message_index; + size_t plaintextLength = olm_group_decrypt(session, mutMessage.mutableBytes, mutMessage.length, plaintextData.mutableBytes, plaintextData.length, &message_index); + if (plaintextLength == olm_error()) { + const char *olm_error = olm_inbound_group_session_last_error(session); + + NSString *errorString = [NSString stringWithUTF8String:olm_error]; + NSLog(@"olm_group_decrypt error: %@", errorString); + + if (error && olm_error && errorString) { + *error = [NSError errorWithDomain:OLMErrorDomain + code:0 + userInfo:@{ + NSLocalizedDescriptionKey: errorString, + NSLocalizedFailureReasonErrorKey: [NSString stringWithFormat:@"olm_group_decrypt error: %@", errorString] + }]; + } + + return nil; + } + plaintextData.length = plaintextLength; + NSString *plaintext = [[NSString alloc] initWithData:plaintextData encoding:NSUTF8StringEncoding]; + [plaintextData resetBytesInRange:NSMakeRange(0, plaintextData.length)]; + + if (messageIndex) + { + *messageIndex = message_index; + } + + return plaintext; +} + + +#pragma mark OLMSerializable + +/** Initializes from encrypted serialized data. Will throw error if invalid key or invalid base64. */ +- (instancetype) initWithSerializedData:(NSString *)serializedData key:(NSData *)key error:(NSError *__autoreleasing *)error { + self = [self init]; + if (!self) { + return nil; + } + NSParameterAssert(key.length > 0); + NSParameterAssert(serializedData.length > 0); + if (key.length == 0 || serializedData.length == 0) { + if (error) { + *error = [NSError errorWithDomain:OLMErrorDomain code:0 userInfo:@{NSLocalizedDescriptionKey: @"Bad length."}]; + } + return nil; + } + NSMutableData *pickle = [serializedData dataUsingEncoding:NSUTF8StringEncoding].mutableCopy; + size_t result = olm_unpickle_inbound_group_session(session, key.bytes, key.length, pickle.mutableBytes, pickle.length); + if (result == olm_error()) { + const char *olm_error = olm_inbound_group_session_last_error(session); + NSString *errorString = [NSString stringWithUTF8String:olm_error]; + if (error && errorString) { + *error = [NSError errorWithDomain:OLMErrorDomain code:0 userInfo:@{NSLocalizedDescriptionKey: errorString}]; + } + return nil; + } + return self; +} + +/** Serializes and encrypts object data, outputs base64 blob */ +- (NSString*) serializeDataWithKey:(NSData*)key error:(NSError**)error { + NSParameterAssert(key.length > 0); + size_t length = olm_pickle_inbound_group_session_length(session); + NSMutableData *pickled = [NSMutableData dataWithLength:length]; + size_t result = olm_pickle_inbound_group_session(session, key.bytes, key.length, pickled.mutableBytes, pickled.length); + if (result == olm_error()) { + const char *olm_error = olm_inbound_group_session_last_error(session); + NSString *errorString = [NSString stringWithUTF8String:olm_error]; + if (error && errorString) { + *error = [NSError errorWithDomain:OLMErrorDomain code:0 userInfo:@{NSLocalizedDescriptionKey: errorString}]; + } + return nil; + } + NSString *pickleString = [[NSString alloc] initWithData:pickled encoding:NSUTF8StringEncoding]; + return pickleString; +} + +#pragma mark NSSecureCoding + ++ (BOOL) supportsSecureCoding { + return YES; +} + +#pragma mark NSCoding + +- (id)initWithCoder:(NSCoder *)decoder { + NSString *version = [decoder decodeObjectOfClass:[NSString class] forKey:@"version"]; + + NSError *error = nil; + + if ([version isEqualToString:@"1"]) { + NSString *pickle = [decoder decodeObjectOfClass:[NSString class] forKey:@"pickle"]; + NSData *key = [decoder decodeObjectOfClass:[NSData class] forKey:@"key"]; + + self = [self initWithSerializedData:pickle key:key error:&error]; + } + + NSParameterAssert(error == nil); + NSParameterAssert(self != nil); + if (!self) { + return nil; + } + + return self; +} + +- (void)encodeWithCoder:(NSCoder *)encoder { + NSData *key = [OLMUtility randomBytesOfLength:32]; + NSError *error = nil; + NSString *pickle = [self serializeDataWithKey:key error:&error]; + NSParameterAssert(pickle.length > 0 && error == nil); + + [encoder encodeObject:pickle forKey:@"pickle"]; + [encoder encodeObject:key forKey:@"key"]; + [encoder encodeObject:@"1" forKey:@"version"]; +} + +@end |