Kestrel prompts

Interfaces that let Luft Keyring and GnuPG ask through Kestrel’s own dialogs. Both are exported by com.lantharos.Kestrel on the session bus. Secrets never cross the bus: they travel through a file descriptor.

Keyring prompter

com.lantharos.Kestrel.KeyringPrompter at /com/lantharos/Kestrel/KeyringPrompter. Only the owner of org.freedesktop.secrets may call it.

Method	Arguments	Returns	Asks
`Access`	`s` handle, `a{sv}` request	`u` response, `a{sv}` results	Whether an app may use something
`Password`	`s` handle, `a{sv}` request, `h` secret	`u` response	A password or PIN, written to the pipe `secret`
`Close`	`s` handle		Closes that prompt

Request keys:

Key	Type	Used by	Meaning
`title`, `body`	`s`	both	Text
`app`	`s`	both	Desktop ID whose icon is shown
`icon`	`s`	both	Symbolic icon when there is no app
`allow`, `deny`	`s`	`Access`	Button labels
`remember`	`b`	`Access`	Offers Remember for this app; returned in the results
`fingerprint`	`b`	both	A fingerprint decides (`Access`), or is offered as an alternative (`Password`)
`label`	`s`	`Password`	Field name
`warning`	`s`	`Password`	Shown above the field, such as after a wrong password
`numeric`	`b`	`Password`	A PIN
`confirm`	`b`	`Password`	Second field that must match
`continue`	`s`	`Password`	Button label

Responses: 0 allowed or entered, 1 declined, 2 closed (by Close, the screen locking, or a newer prompt with the same handle).
After Password returns, the dialog stays open until Close; calling Password again with the same handle and a warning asks again in the same dialog.
One prompt shows at a time, prompts wait while the screen is locked, and handles are separate per caller.

Pinentry

com.lantharos.Kestrel.Pinentry at /com/lantharos/Kestrel/Pinentry, used by luft-pinentry.

Method	Arguments	Returns
`Password`	`s` handle, `a{sv}` request, `h` channel	`u` response, `a{sv}` results (`remember`)
`Confirm`	`s` handle, `a{sv}` request	`u` response
`Close`	`s` handle

Password requests can also carry cancel, mismatch (warning when two entries differ), remember (offers Save in your keyring) and quality (shows GnuPG’s passphrase rating while typing).
Confirmations can carry alternative, a third button answered with 3, and single, for a message with one button.
The channel is a socket: Kestrel writes Q<length> and the passphrase so far when it needs a rating and reads the rating back as a line, then writes P<length> and the passphrase once entered.