Add prompt implementation for service method lock

Even though gnome-keyring-daemon doesn't implement/show a prompt during
the service method lock. The secret service spec says a prompt can be
used during lock. So, we're adding this to the new daemon.

Signed-off-by: Dhanuka Warusadura <dhanuka@gnome.org>

Author: warusadura

server/src/gnome/mod.rs

@@ -1 +1,2 @@
-mod secret_exchange;
+pub mod prompter;
+pub mod secret_exchange;

server/src/gnome/prompter.rs

@@ -0,0 +1,291 @@
+// org.gnome.keyring.Prompter
+// https://gitlab.gnome.org/GNOME/gcr/-/blob/main/gcr/org.gnome.keyring.Prompter.xml
+
+use clap::error::Result;
+use oo7::dbus::ServiceError;
+use serde::{Deserialize, Serialize};
+use zbus::{
+    interface, proxy,
+    zvariant::{DeserializeDict, OwnedObjectPath, OwnedValue, SerializeDict, Type, Value},
+};
+
+use crate::{
+    gnome::secret_exchange::SecretExchange,
+    prompt::{Prompt, PromptRole},
+    service::Service,
+};
+
+#[derive(Debug, DeserializeDict, SerializeDict, Type)]
+#[zvariant(signature = "a{sv}")]
+// System prompt properties
+pub struct Properties {
+    title: Option<String>,
+    #[zvariant(rename = "choice-label")]
+    choice_label: Option<String>,
+    description: Option<String>,
+    message: Option<String>,
+    #[zvariant(rename = "caller-window")]
+    caller_window: Option<String>,
+    warning: Option<String>,
+    #[zvariant(rename = "password-new")]
+    password_new: Option<bool>,
+    #[zvariant(rename = "password-strength")]
+    password_strength: Option<u32>,
+    #[zvariant(rename = "choice-chosen")]
+    choice_chosen: Option<bool>,
+    #[zvariant(rename = "continue-label")]
+    continue_label: Option<String>,
+    #[zvariant(rename = "cancel-label")]
+    cancel_label: Option<String>,
+}
+
+impl Properties {
+    fn for_lock() -> Self {
+        Self {
+            title: Some("Lock Keyring".to_string()),
+            choice_label: None,
+            description: Some("Confirm locking 'login' Keyring".to_string()),
+            message: Some("Lock Keyring".to_string()),
+            caller_window: None,
+            warning: None,
+            password_new: Some(false),
+            password_strength: Some(0),
+            choice_chosen: Some(false),
+            continue_label: Some("Lock".to_string()),
+            cancel_label: Some("Cancel".to_string()),
+        }
+    }
+}
+
+#[derive(Debug, Type)]
+#[zvariant(signature = "s")]
+// Possible values for PromptReady reply parameter
+pub enum Reply {
+    No,
+    Yes,
+    Empty,
+}
+
+const NO: &str = "no";
+const YES: &str = "yes";
+const EMPTY: &str = "";
+
+impl Serialize for Reply {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        match self {
+            Self::No => str::serialize(NO, serializer),
+            Self::Yes => str::serialize(YES, serializer),
+            Self::Empty => str::serialize(EMPTY, serializer),
+        }
+    }
+}
+
+impl<'de> Deserialize<'de> for Reply {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        match String::deserialize(deserializer)?.as_str() {
+            NO => Ok(Self::No),
+            YES => Ok(Self::Yes),
+            EMPTY => Ok(Self::Empty),
+            err => Err(serde::de::Error::custom(format!("Invalid reply {err}"))),
+        }
+    }
+}
+
+#[derive(Deserialize, Serialize, Debug, Type)]
+#[serde(rename_all = "lowercase")]
+#[zvariant(signature = "s")]
+// Possible values for PerformPrompt type parameter
+pub enum PromptType {
+    Confirm,
+    Password,
+}
+
+// org.gnome.keyring.internal.Prompter
+
+#[proxy(
+    default_service = "org.gnome.keyring.SystemPrompter",
+    interface = "org.gnome.keyring.internal.Prompter",
+    default_path = "/org/gnome/keyring/Prompter"
+)]
+pub trait Prompter {
+    fn begin_prompting(&self, callback: &OwnedObjectPath) -> Result<(), ServiceError>;
+
+    fn perform_prompt(
+        &self,
+        callback: OwnedObjectPath,
+        type_: PromptType,
+        properties: Properties,
+        exchange: &str,
+    ) -> Result<(), ServiceError>;
+
+    fn stop_prompting(&self, callback: OwnedObjectPath) -> Result<(), ServiceError>;
+}
+
+// org.gnome.keyring.internal.Prompter.Callback
+
+pub struct PrompterCallback {
+    service: Service,
+    path: OwnedObjectPath,
+}
+
+#[interface(name = "org.gnome.keyring.internal.Prompter.Callback")]
+impl PrompterCallback {
+    pub async fn prompt_ready(
+        &self,
+        reply: Reply,
+        _properties: Properties,
+        exchange: &str,
+        #[zbus(connection)] connection: &zbus::Connection,
+    ) -> Result<(), ServiceError> {
+        let Some(prompt) = self.service.prompt().await else {
+            return Err(ServiceError::NoSuchObject(
+                "Prompt does not exist.".to_string(),
+            ));
+        };
+
+        match prompt.role() {
+            PromptRole::Lock => {
+                match reply {
+                    Reply::Empty => {
+                        // First PromptReady call
+                        let secret_exchange = SecretExchange::new().map_err(|err| {
+                            ServiceError::ZBus(zbus::Error::FDO(Box::new(
+                                zbus::fdo::Error::Failed(format!(
+                                    "Failed to generate SecretExchange {err}."
+                                )),
+                            )))
+                        })?;
+                        let exchange = secret_exchange.begin();
+
+                        let properties = Properties::for_lock();
+                        let path = self.path.clone();
+
+                        tokio::spawn(PrompterCallback::perform_prompt(
+                            connection.clone(),
+                            path,
+                            PromptType::Confirm,
+                            properties,
+                            exchange,
+                        ));
+                    }
+                    Reply::No => {
+                        // Second PromptReady call and the prompt is dismissed
+                        tracing::debug!("Prompt is being dismissed.");
+
+                        tokio::spawn(PrompterCallback::stop_prompting(
+                            connection.clone(),
+                            self.path.clone(),
+                        ));
+
+                        let signal_emitter = self.service.signal_emitter(prompt.path().clone())?;
+                        let result = Value::new::<Vec<OwnedObjectPath>>(vec![])
+                            .try_to_owned()
+                            .unwrap();
+
+                        tokio::spawn(PrompterCallback::prompt_completed(
+                            signal_emitter,
+                            true,
+                            result,
+                        ));
+                    }
+                    Reply::Yes => {
+                        // Second PromptReady call with the final exchange
+                        let service = self.service.clone();
+                        let objects = prompt.objects().clone();
+                        let result = Value::new(&objects).try_to_owned().unwrap();
+
+                        tokio::spawn(async move {
+                            let _ = service.set_locked(true, &objects, true).await;
+                        });
+
+                        tokio::spawn(PrompterCallback::stop_prompting(
+                            connection.clone(),
+                            self.path.clone(),
+                        ));
+
+                        let signal_emitter = self.service.signal_emitter(prompt.path().clone())?;
+
+                        tokio::spawn(PrompterCallback::prompt_completed(
+                            signal_emitter,
+                            false,
+                            result,
+                        ));
+                    }
+                }
+            }
+            PromptRole::Unlock => todo!(),
+            PromptRole::CreateCollection => todo!(),
+        };
+
+        Ok(())
+    }
+
+    pub async fn prompt_done(
+        &self,
+        #[zbus(object_server)] object_server: &zbus::ObjectServer,
+    ) -> Result<(), ServiceError> {
+        if let Some(prompt) = self.service.prompt().await {
+            object_server.remove::<Prompt, _>(prompt.path()).await?;
+            self.service.remove_prompt().await;
+        }
+        object_server.remove::<Self, _>(&self.path).await?;
+
+        Ok(())
+    }
+}
+
+impl PrompterCallback {
+    pub async fn new(service: Service) -> Self {
+        let index = service.prompt_index().await;
+        Self {
+            path: OwnedObjectPath::try_from(format!("/org/gnome/keyring/Prompt/p{index}")).unwrap(),
+            service,
+        }
+    }
+
+    pub fn path(&self) -> &OwnedObjectPath {
+        &self.path
+    }
+
+    pub async fn perform_prompt(
+        connection: zbus::Connection,
+        path: OwnedObjectPath,
+        prompt_type: PromptType,
+        properties: Properties,
+        exchange: String,
+    ) -> Result<(), ServiceError> {
+        let prompter = PrompterProxy::new(&connection).await?;
+        prompter
+            .perform_prompt(path, prompt_type, properties, &exchange)
+            .await?;
+
+        Ok(())
+    }
+
+    pub async fn stop_prompting(
+        connection: zbus::Connection,
+        path: OwnedObjectPath,
+    ) -> Result<(), ServiceError> {
+        let prompter = PrompterProxy::new(&connection).await?;
+        prompter.stop_prompting(path).await?;
+
+        Ok(())
+    }
+
+    pub async fn prompt_completed(
+        signal_emitter: zbus::object_server::SignalEmitter<'_>,
+        dismissed: bool,
+        result: OwnedValue,
+    ) -> Result<(), ServiceError> {
+        Prompt::completed(&signal_emitter, dismissed, result).await?;
+        tracing::debug!("Prompt completed.");
+
+        Ok(())
+    }
+}

server/src/prompt.rs

@@ -1,25 +1,95 @@
 // org.freedesktop.Secret.Prompt
 
 use oo7::dbus::ServiceError;
-use zbus::{interface, object_server::SignalEmitter, zvariant::OwnedValue};
+use zbus::{
+    interface,
+    object_server::SignalEmitter,
+    zvariant::{OwnedObjectPath, OwnedValue},
+};
 
-#[derive(Debug)]
-pub struct Prompt {}
+use crate::{
+    gnome::prompter::{PrompterCallback, PrompterProxy},
+    service::Service,
+};
+
+#[derive(Debug, Clone)]
+#[allow(unused)]
+pub enum PromptRole {
+    Lock,
+    Unlock,
+    CreateCollection,
+}
+
+#[derive(Debug, Clone)]
+pub struct Prompt {
+    service: Service,
+    objects: Vec<OwnedObjectPath>,
+    role: PromptRole,
+    path: OwnedObjectPath,
+}
 
 #[interface(name = "org.freedesktop.Secret.Prompt")]
 impl Prompt {
-    pub async fn prompt(&self, _window_id: &str) -> Result<(), ServiceError> {
-        todo!()
+    pub async fn prompt(
+        &self,
+        _window_id: &str,
+        #[zbus(connection)] connection: &zbus::Connection,
+        #[zbus(object_server)] object_server: &zbus::ObjectServer,
+    ) -> Result<(), ServiceError> {
+        let callback = PrompterCallback::new(self.service.clone()).await;
+        let path = callback.path().clone();
+        let connection = connection.clone();
+
+        object_server.at(&path, callback).await?;
+        tracing::debug!("Prompt `{}` created.", self.path);
+
+        tokio::spawn(async move {
+            let prompter = PrompterProxy::new(&connection).await.unwrap();
+            prompter.begin_prompting(&path).await.unwrap();
+        });
+
+        Ok(())
     }
 
-    pub async fn dismiss(&self) -> Result<(), ServiceError> {
-        todo!()
+    pub async fn dismiss(
+        &self,
+        #[zbus(object_server)] object_server: &zbus::ObjectServer,
+    ) -> Result<(), ServiceError> {
+        object_server.remove::<Self, _>(&self.path).await?;
+        self.service.remove_prompt().await;
+
+        Ok(())
     }
 
     #[zbus(signal, name = "Completed")]
-    async fn completed(
+    pub async fn completed(
         signal_emitter: &SignalEmitter<'_>,
         dismissed: bool,
         result: OwnedValue,
     ) -> zbus::Result<()>;
 }
+
+impl Prompt {
+    pub async fn new(service: Service, objects: Vec<OwnedObjectPath>, role: PromptRole) -> Self {
+        let index = service.prompt_index().await;
+        Self {
+            path: OwnedObjectPath::try_from(format!("/org/freedesktop/secrets/prompt/p{index}"))
+                .unwrap(),
+            service,
+            objects,
+            role,
+        }
+    }
+
+    pub fn path(&self) -> &OwnedObjectPath {
+        &self.path
+    }
+
+    pub fn role(&self) -> &PromptRole {
+        &self.role
+    }
+
+    pub fn objects(&self) -> &Vec<OwnedObjectPath> {
+        &self.objects
+    }
+}