Merge pull request #1885 from matrix-org/mauroromito/restore_create_k…

…ey_with_id

Restore `createKeyWithKeyId`

MatrixSDK/Crypto/SecretStorage/MXSecretStorage.m

@@ -18,12 +18,14 @@
 
 #import "MXSession.h"
 #import "MXTools.h"
+#import "MXKeyBackupPassword.h"
 #import "MXRecoveryKey.h"
 #import "MXHkdfSha256.h"
 #import "MXAesHmacSha2.h"
 #import "MXBase64Tools.h"
 #import "MXEncryptedSecretContent.h"
 
+#import <Security/Security.h>
 
 #pragma mark - Constants
 
@@ -126,6 +128,112 @@ - (MXHTTPOperation*)createKeyWithKeyId:(nullable NSString*)keyId
     return operation;
 }
 
+- (MXHTTPOperation*)createKeyWithKeyId:(nullable NSString*)keyId
+                               keyName:(nullable NSString*)keyName
+                            passphrase:(nullable NSString*)passphrase
+                               success:(void (^)(MXSecretStorageKeyCreationInfo *keyCreationInfo))success
+                               failure:(void (^)(NSError *error))failure
+{
+    MXLogDebug(@"[MXSecretStorage] createKeyWithKeyId: Creating new key with passphrase");
+    keyId = keyId ?: [[NSUUID UUID] UUIDString];
+
+    MXHTTPOperation *operation = [MXHTTPOperation new];
+
+    MXWeakify(self);
+    dispatch_async(processingQueue, ^{
+        MXStrongifyAndReturnIfNil(self);
+
+        NSError *error;
+
+        NSData *privateKey;
+        MXSecretStoragePassphrase *passphraseInfo;
+
+        if (passphrase)
+        {
+            // Generate a private key from the passphrase
+            NSString *salt;
+            NSUInteger iterations;
+            privateKey = [MXKeyBackupPassword generatePrivateKeyWithPassword:passphrase
+                                                                        salt:&salt
+                                                                  iterations:&iterations
+                                                                       error:&error];
+            if (!error)
+            {
+                passphraseInfo = [MXSecretStoragePassphrase new];
+                passphraseInfo.algorithm = @"m.pbkdf2";
+                passphraseInfo.salt = salt;
+                passphraseInfo.iterations = iterations;
+            }
+        }
+        else
+        {
+            uint8_t randomBytes[32];
+            OSStatus status = SecRandomCopyBytes(kSecRandomDefault, sizeof(randomBytes), randomBytes);
+
+            if (status == errSecSuccess)
+            {
+                privateKey = [NSData dataWithBytes:randomBytes length:sizeof(randomBytes)];
+            }
+            else
+            {
+                MXLogDebug(@"Failed to generate random bytes with error: %d", (int)status);
+            }
+        }
+
+        if (error)
+        {
+            dispatch_async(dispatch_get_main_queue(), ^{
+                MXLogDebug(@"[MXSecretStorage] createKeyWithKeyId: Failed to create a new key - %@", error);
+                failure(error);
+            });
+            return;
+        }
+
+        // Build iv and mac
+        MXEncryptedSecretContent *encryptedZeroString = [self encryptedZeroStringWithPrivateKey:privateKey iv:nil error:&error];
+        if (error)
+        {
+            dispatch_async(dispatch_get_main_queue(), ^{
+                MXLogDebug(@"[MXSecretStorage] createKeyWithKeyId: Failed to create a new key - %@", error);
+                failure(error);
+            });
+            return;
+        }
+
+        MXSecretStorageKeyContent *ssssKeyContent = [MXSecretStorageKeyContent new];
+        ssssKeyContent.name = keyName;
+        ssssKeyContent.algorithm = MXSecretStorageKeyAlgorithm.aesHmacSha2;
+        ssssKeyContent.passphrase = passphraseInfo;
+        ssssKeyContent.iv = encryptedZeroString.iv;
+        ssssKeyContent.mac = encryptedZeroString.mac;
+
+        NSString *accountDataId = [self storageKeyIdForKey:keyId];
+        MXHTTPOperation *operation2 = [self setAccountData:ssssKeyContent.JSONDictionary forType:accountDataId success:^{
+
+            MXSecretStorageKeyCreationInfo *keyCreationInfo = [MXSecretStorageKeyCreationInfo new];
+            keyCreationInfo.keyId = keyId;
+            keyCreationInfo.content = ssssKeyContent;
+            keyCreationInfo.privateKey = privateKey;
+            keyCreationInfo.recoveryKey = [MXRecoveryKey encode:privateKey];
+
+            dispatch_async(dispatch_get_main_queue(), ^{
+                MXLogDebug(@"[MXSecretStorage] createKeyWithKeyId: Successfully created a new key");
+                success(keyCreationInfo);
+            });
+
+        } failure:^(NSError *error) {
+            dispatch_async(dispatch_get_main_queue(), ^{
+                MXLogDebug(@"[MXSecretStorage] createKeyWithKeyId: Failed to create a new key - %@", error);
+                failure(error);
+            });
+        }];
+
+        [operation mutateTo:operation2];
+    });
+
+    return operation;
+}
+
 - (MXHTTPOperation*)deleteKeyWithKeyId:(nullable NSString*)keyId
                                success:(void (^)(void))success
                                failure:(void (^)(NSError *error))failure