No message error/Give up on "Input encryption key" dialog

[eduardomozart]

Describe the bug

In the "Input encryption key" dialog set to "Always" on program settings, it requests the password every time the program starts and is only dismissed when the user types the correct password, as intended.

Also, I couldn't figure out the difference between "Input encryption key" and "Input password", as the UI to encrypt the connection password only offers a password option, and for it to work, I have to select "Input password" and type the password I set up on the application; otherwise, it reopens the dialog again.

To Reproduce
Steps to reproduce the behavior:

1. Go to 'Settings'
2. Click on 'Plugin'
3. "Enable save password", type an "Encryption key" and select to "Always" ask password.
4. Close the program and reopen it.

Expected behavior

• When pressing ESC, the program should stop attempting to ask the password the same way it does when the user clicks on "No", and only ask again when starting a connection with an encrypted password.
• When typing the wrong password, the program should state that the password is wrong instead of simply opening "Input encryption key" dialog again.
• I believe the issue is related to the number of operations you have connected and saved passwords - if I'm not wrong, I had filled two RDP connections with saved passwords.

Application details

• The application version: 0.0.36-316-g67f307d9 (From revision: 67f307d9) Arch: x86_64
• Compile date: Aug 29 2025/04:29:05

Qt
Version: 6.9.1

System information

Desktop (please complete the following information):

• OS: macOS Sequoia
• Version: 15.6.1

Additional context
Add any other context about the problem here.

[KangLin]

@eduardomozart

When typing the wrong password, the program should state that the password is wrong instead of simply opening "Input encryption key" dialog again.

This only checks whether the encryption key is correct. can't check password.
Currently, it is possible to support each operation corresponding to a different encryption key.
So it will be relatively complicated. The prompt dialog box may appear multiple times.
I think it can be limited to using the same encryption key for all operations.
Do you have a better idea?

[eduardomozart]

Is it currently possible to use multiple encryption keys?

I do believe a better approach would be to decrypt the keys using the current encryption key to decrypt the current passwords and use the latest one to reencrypt all passwords, because if we're changing the encryption key, it's because we believe it may have been compromised, and we want to protect our data. Also, implementing QtKeychain reinforces security since only if the user knows the current system user password can decrypt the saved encryption key, instead of saving it inside the config file - if the user password is reseted using tools like Chntpw, Windows wouldn't be able to decrypt the password and ask it again with the 'Input encryption key' dialog.

Having multiple encryption keys may also create issues while decrypting the keys, which would require an approach similar to DPAPI (image below): the user should know the current key to decrypt the previous key, etc., until decrypting all passwords. DPAPI handles decrypting data using multiple encryption keys, but it doesn't seem feasible to implement such a feature, as there's no open source implementation of DPAPI available for other operating systems than Windows.

A workaround would be using QtKeychain to keep track of all encryption keys and attempting to use them to decrypt the password of an entry, using the current system user password. But it would create multiple entries on the operating system Vault, and if the user deletes one because he/she think it's duplicated, it would break all the keychains, or if he/she format the operating system, the other keys are lost, which would make it very difficult for the user to remember all the encryption keys to be able to decrypt all the password data.

[KangLin]

#78 is finished.
I want to keep this feature for #53. When using it on different machines, you just need to copy the configuration files to use it. Of course, it can also be accessed over the network. For example: SMB.

Use case1: The user uses an encryption key.
Use case2: The user forget the encyption key.
Use case3: Other user has other enctyption key.

When restore the password, if the encryption key is incorrect, Password is set to empty. it proceeds to the normal password entry.

When store the password, remove Always prompt. Because if the encryption key is empty, it is considered as not using encryption.

After the above modifications, prompt dialog interruptions can be reduced.