objective-c - 如何在 OS X 中成功删除钥匙串(keychain)中的项目？

Question

如何在 OS X 中成功删除钥匙串(keychain)中的项目？这是我到目前为止所拥有的，但它在 SecItemDelete 调用时失败。我需要在查询字典中指定一些额外的属性吗？我可以通过执行类似的操作成功地将键值对插入到钥匙串(keychain)中。

#define DELETE_SIZE 3
bool delete_key_keychain( const char *cKeyValue, SecKeychainRef keychain) {
    if ( !keychain)
        return false;

    // Convert to CFString.
    CFStringRef keyValue = CFStringCreateWithCString( NULL, cKeyValue, kCFStringEncodingUTF8);
    if ( !keyValue)
        return false;

    // Specify query parameters.
    const void *keys[DELETE_SIZE] = {
        kSecClass,
        kSecUseKeychain,
        kSecAttrAccount
    };
    const void *values[DELETE_SIZE] = {
        kSecClassGenericPassword,
        keychain,
        keyValue
    };

    // Create query.
    CFDictionaryRef query = CFDictionaryCreate( NULL, keys, values, GET_SIZE, NULL, NULL);
    if ( !query) {
        CFRelease( keyValue);
        return false;
    }

    // Run query.
    OSStatus status = SecItemDelete( query);
    CFRelease( query);
    CFRelease( keyValue);

    return status == errSecSuccess;
}

更新:根据此link ，我需要在查询中设置 kSecAttrService 属性。因此，我开始使用 SecKeychainFindGenericPassword 和 SecKeychainItemDelete。这将成功删除密码，但是随后为同一帐户添加不同的密码可能会导致崩溃。因此，我开始使用 SecKeychainItemModifyAttributesAndData 来修改密码并且不删除密码。我认为这种不稳定可能是由于 API 执行的缓存造成的。

Answer 1

过去，我曾使用此功能从我的 Mac OS 钥匙串(keychain)中删除特定的公钥/私钥对项目

// remove keypair from keychain
- (BOOL)deleteKeysFromKeychain {
    OSStatus sanityCheck1 = noErr;
    OSStatus sanityCheck2 = noErr;

    NSMutableDictionary * queryPublicKey = [[NSMutableDictionary alloc] init];
    NSMutableDictionary * queryPrivateKey = [[NSMutableDictionary alloc] init];

    // Set the public key query dictionary.
    [queryPublicKey setObject:(__bridge id)kSecClassKey forKey:(__bridge id)kSecClass];
    [queryPublicKey setObject:self.myPublicTag forKey:(__bridge id)kSecAttrApplicationTag];
    [queryPublicKey setObject:(__bridge id)kSecAttrKeyTypeRSA forKey:(__bridge id)kSecAttrKeyType];

    // Set the private key query dictionary.
    [queryPrivateKey setObject:(__bridge id)kSecClassKey forKey:(__bridge id)kSecClass];
    [queryPrivateKey setObject:self.myPrivateTag forKey:(__bridge id)kSecAttrApplicationTag];
    [queryPrivateKey setObject:(__bridge id)kSecAttrKeyTypeRSA forKey:(__bridge id)kSecAttrKeyType];

    // Delete the private key.
    sanityCheck1 = SecItemDelete((__bridge CFDictionaryRef)queryPrivateKey);

    // Delete the public key.
    sanityCheck2 = SecItemDelete((__bridge CFDictionaryRef)queryPublicKey);

    @autoreleasepool {
        queryPrivateKey = nil;
        queryPublicKey = nil;
    }

    return ( sanityCheck1 == sanityCheck2  && sanityCheck2 == noErr ? YES : NO );    
}

其中 myPublicTag 类似于 'com.yourAppName.publickey'

其中 myPrivateTag 类似于 'com.yourAppName.privatekey'

也许这会有用