feat: ajouter le Credential Vault (memorisation securisee optionnelle)

Par defaut, inchange : les mots de passe sont toujours redemandes a chaque
connexion. Nouvelle case a cocher optionnelle dans l'editeur de session,
visible seulement en authentification par mot de passe : "Memoriser le mot
de passe de maniere securisee".

- app/credentials.py : abstraction CredentialStore (set_secret/get_secret/
  delete_secret/is_available), pour supporter plus tard d'autres systemes que
  Windows. WindowsCredentialStore utilise Windows Credential Manager
  (CredWrite/CredRead/CredDelete) via pywin32-ctypes - deja present dans
  l'environnement (dependance de PyInstaller), mais pas encore declare comme
  dependance d'execution : ajoute a requirements.txt (marque sys_platform ==
  "win32"), sinon la fonctionnalite aurait silencieusement ete indisponible
  sur une installation propre. NullCredentialStore en repli si indisponible :
  jamais d'ecriture en clair a la place.
- Session.password_storage ("none" par defaut | "secure") : seulement le mode
  est stocke dans sessions.json, jamais le secret. Le mot de passe est ecrit/
  lu dans le trousseau via une cle applicative (session:<id>), et supprime
  automatiquement si l'utilisateur desactive la memorisation ou supprime la
  session.
- Un bastion en mode "session PySSH" reutilise un mot de passe deja memorise
  pour cette session (lecture seule depuis ce chemin : l'ecriture ne se fait
  que via l'ouverture directe de la session concernee).

tests/test_credentials.py : NullCredentialStore, aller-retour reel avec
Windows Credential Manager (nettoye et verifie apres coup, aucune entree
residuelle), integration ConnectionController (memorise puis reutilise sans
redemander), suppression en cascade, reutilisation par un bastion, et
verification que le secret n'apparait jamais dans la serialisation JSON de
la session.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

app/bastion.py

@@ -14,6 +14,7 @@ from app.session_manager import (
     BASTION_NONE, BASTION_SESSION, BASTION_OPENSSH, BASTION_MANUAL,
     AUTH_AUTO, AUTH_KEY,
 )
+from app.credentials import session_credential_key
 
 
 class BastionResolutionError(Exception):
@@ -29,6 +30,11 @@ class BastionTarget:
     username: str
     auth_type: str
     key_path: str = ""
+    # Non vide seulement pour un bastion en mode "session PySSH" : permet de
+    # reutiliser un mot de passe deja memorise pour cette session (voir
+    # app.credentials), sans que ce module ait besoin de connaitre le
+    # CredentialStore lui-meme.
+    credential_key: str = ""
 
     @property
     def label(self) -> str:
@@ -57,7 +63,10 @@ def resolve_bastion_target(
             raise BastionResolutionError(
                 "La session utilisee comme bastion est introuvable (supprimee ou renommee)."
             )
-        return BastionTarget(target.host, target.port, target.username, target.auth_type, target.key_path)
+        return BastionTarget(
+            target.host, target.port, target.username, target.auth_type, target.key_path,
+            credential_key=session_credential_key(target.id),
+        )
 
     if bastion.mode == BASTION_OPENSSH:
         from app.openssh.config import load_openssh_hosts

app/controllers/connection_controller.py

@@ -5,7 +5,7 @@ from __future__ import annotations
 from PySide6.QtCore import Qt, Signal, QObject
 from PySide6.QtWidgets import QTabWidget, QWidget, QMenu, QMessageBox, QInputDialog
 
-from app.session_manager import SessionStore, Session, AUTH_PASSWORD
+from app.session_manager import SessionStore, Session, AUTH_PASSWORD, PASSWORD_STORAGE_SECURE
 from app.key_manager import KeyManager
 from app.local_terminal import DEFAULT_SHELL, SHELL_LABELS
 from app.dialogs.session_dialog import SessionDialog
@@ -13,6 +13,7 @@ from app.dialogs.connect_prompt import ask_secret
 from app.services.ssh_target import detect_ssh_target
 from app.openssh.config import OpenSSHHost, session_from_openssh_host
 from app.bastion import BastionTarget, resolve_bastion_target, BastionResolutionError
+from app.credentials import CredentialStore, NullCredentialStore, session_credential_key
 from app.controllers.broadcast_manager import BroadcastManager
 from app.ui.tabs import BaseTerminalTab, SessionTabWidget, SFTPTabWidget, LocalTerminalTabWidget
 from app.ui.split_pane import SplitContainer, PaneSlot, LAYOUT_LABELS
@@ -31,6 +32,7 @@ class ConnectionController(QObject):
         key_manager: KeyManager,
         broadcast: BroadcastManager,
         snippet_store=None,
+        credential_store: CredentialStore | None = None,
         parent_widget: QWidget | None = None,
     ):
         super().__init__(parent_widget)
@@ -38,6 +40,7 @@ class ConnectionController(QObject):
         self.key_manager = key_manager
         self.broadcast = broadcast
         self.snippet_store = snippet_store
+        self.credential_store = credential_store or NullCredentialStore()
         self._parent_widget = parent_widget
 
         self.tabs = QTabWidget(parent_widget)
@@ -62,6 +65,13 @@ class ConnectionController(QObject):
             return True, None, ""
         if target.auth_type != AUTH_PASSWORD:
             return True, target, ""
+        # Un bastion "session PySSH" reutilise un mot de passe deja memorise pour
+        # cette session (s'il en existe un) : jamais ecrit depuis ce chemin, on ne
+        # fait que lire ce que l'ouverture directe de cette session aurait memorise.
+        if target.credential_key:
+            stored = self.credential_store.get_secret(target.credential_key)
+            if stored is not None:
+                return True, target, stored
         text, ok = ask_secret(
             self._parent_widget, "Mot de passe du bastion", f"Mot de passe pour {target.label} (bastion) :",
         )
@@ -72,9 +82,17 @@ class ConnectionController(QObject):
     def _ask_session_password(self, session: Session) -> tuple[bool, str]:
         if session.auth_type != AUTH_PASSWORD:
             return True, ""
+        remember = session.password_storage == PASSWORD_STORAGE_SECURE
+        key = session_credential_key(session.id)
+        if remember:
+            stored = self.credential_store.get_secret(key)
+            if stored is not None:
+                return True, stored
         text, ok = ask_secret(
             self._parent_widget, "Mot de passe", f"Mot de passe pour {session.username}@{session.host} :"
         )
+        if ok and remember:
+            self.credential_store.set_secret(key, text)
         return ok, (text if ok else "")
 
     def build_session_tab(self, session: Session) -> SessionTabWidget | None:
@@ -176,6 +194,7 @@ class ConnectionController(QObject):
             connect_label="Se connecter",
             title="Connexion SFTP" if sftp else "Connexion SSH",
             session_store=self.session_store,
+            credential_store=self.credential_store,
         )
         if not dialog.exec():
             return

app/controllers/session_controller.py

@@ -15,6 +15,7 @@ from PySide6.QtWidgets import (
 from app.session_manager import SessionStore, Session
 from app.key_manager import KeyManager
 from app.groups import GroupSettingsStore
+from app.credentials import CredentialStore, NullCredentialStore, session_credential_key
 from app.local_terminal import SHELL_LABELS
 from app.dialogs.session_dialog import SessionDialog
 from app.dialogs.group_settings_dialog import GroupSettingsDialog
@@ -45,11 +46,13 @@ class SessionController(QObject):
         parent_widget: QWidget | None = None,
         openssh_config_path=None,
         group_store: GroupSettingsStore | None = None,
+        credential_store: CredentialStore | None = None,
     ):
         super().__init__(parent_widget)
         self.session_store = session_store
         self.key_manager = key_manager
         self.group_store = group_store
+        self.credential_store = credential_store or NullCredentialStore()
         self._parent_widget = parent_widget
         self._openssh_config_path = openssh_config_path or default_config_path()
 
@@ -322,6 +325,7 @@ class SessionController(QObject):
         dialog = SessionDialog(
             self.key_manager, session=prefill, parent=self._parent_widget,
             session_store=self.session_store, group_store=self.group_store,
+            credential_store=self.credential_store,
         )
         if dialog.exec():
             self.session_store.add(dialog.result_session())
@@ -331,6 +335,7 @@ class SessionController(QObject):
         dialog = SessionDialog(
             self.key_manager, session=session, parent=self._parent_widget,
             session_store=self.session_store, group_store=self.group_store,
+            credential_store=self.credential_store,
         )
         if dialog.exec():
             self.session_store.update(dialog.result_session())
@@ -348,6 +353,7 @@ class SessionController(QObject):
             self._parent_widget, "Supprimer", f"Supprimer la session '{session.name}' ?"
         ) == QMessageBox.Yes:
             self.session_store.delete(session.id)
+            self.credential_store.delete_secret(session_credential_key(session.id))
             self.reload()
 
     # ---------- OpenSSH config ----------
@@ -357,7 +363,7 @@ class SessionController(QObject):
         dialog = SessionDialog(
             self.key_manager, session=session_from_openssh_host(host), parent=self._parent_widget,
             title=f"Importer « {host.alias} » comme session", session_store=self.session_store,
-            group_store=self.group_store,
+            group_store=self.group_store, credential_store=self.credential_store,
         )
         if dialog.exec():
             self.session_store.add(dialog.result_session())

app/credentials.py

@@ -0,0 +1,128 @@
+"""Stockage securise optionnel des secrets (mots de passe de session, cles API
+de l'assistant IA...).
+
+Par defaut, PySSH ne memorise aucun secret : ils sont redemandes a chaque
+usage. CredentialStore permet d'activer, au cas par cas, une memorisation via
+le trousseau du systeme - jamais en clair dans un fichier JSON, jamais logue.
+
+Sous Windows : Windows Credential Manager, via les fonctions CredWrite/
+CredRead/CredDelete exposees par pywin32-ctypes (deja une dependance
+existante de l'application - inutile d'ajouter pywin32 ou keyring rien que
+pour ceci). Le secret est protege par DPAPI au niveau du systeme
+d'exploitation ; PySSH ne manipule jamais la cle de chiffrement elle-meme.
+
+Ailleurs (Linux/macOS) : aucun trousseau integre equivalent sans dependance
+supplementaire pour l'instant. NullCredentialStore signale simplement
+l'indisponibilite plutot que d'ecrire un secret en clair, pour ne jamais
+donner une fausse impression de securite. C'est le point d'extension prevu
+pour un futur backend (ex: Secret Service / Keychain).
+"""
+from __future__ import annotations
+
+import abc
+import os
+
+_TARGET_PREFIX = "PySSHClient/"
+
+
+def session_credential_key(session_id: str) -> str:
+    return f"session:{session_id}"
+
+
+class CredentialStore(abc.ABC):
+    """Une `key` est un identifiant applicatif (ex: "session:<id>",
+    "ai:api_key") : jamais le secret lui-meme."""
+
+    @abc.abstractmethod
+    def is_available(self) -> bool:
+        """False si aucun trousseau securise n'est utilisable sur ce poste."""
+
+    @abc.abstractmethod
+    def set_secret(self, key: str, secret: str) -> bool:
+        """Memorise `secret`. Renvoie False en cas d'echec (jamais d'exception)."""
+
+    @abc.abstractmethod
+    def get_secret(self, key: str) -> str | None:
+        """None si absent ou si le trousseau est indisponible."""
+
+    @abc.abstractmethod
+    def delete_secret(self, key: str) -> None:
+        """Ne leve jamais si la cle est deja absente."""
+
+
+class NullCredentialStore(CredentialStore):
+    """Repli quand aucun trousseau securise n'est disponible."""
+
+    def is_available(self) -> bool:
+        return False
+
+    def set_secret(self, key: str, secret: str) -> bool:
+        return False
+
+    def get_secret(self, key: str) -> str | None:
+        return None
+
+    def delete_secret(self, key: str) -> None:
+        pass
+
+
+class WindowsCredentialStore(CredentialStore):
+    """Windows Credential Manager (CRED_TYPE_GENERIC)."""
+
+    def __init__(self):
+        try:
+            import win32ctypes.pywin32.win32cred as win32cred
+            self._win32cred = win32cred
+        except ImportError:
+            self._win32cred = None
+
+    def is_available(self) -> bool:
+        return self._win32cred is not None
+
+    def _target(self, key: str) -> str:
+        return _TARGET_PREFIX + key
+
+    def set_secret(self, key: str, secret: str) -> bool:
+        if self._win32cred is None:
+            return False
+        try:
+            self._win32cred.CredWrite({
+                "Type": self._win32cred.CRED_TYPE_GENERIC,
+                "TargetName": self._target(key),
+                "UserName": os.environ.get("USERNAME", "pyssh"),
+                "CredentialBlob": secret,
+                "Comment": "PySSH Client",
+                "Persist": self._win32cred.CRED_PERSIST_LOCAL_MACHINE,
+            }, 0)
+            return True
+        except Exception:  # noqa: BLE001 - jamais bloquant : au pire, on redemandera le secret
+            return False
+
+    def get_secret(self, key: str) -> str | None:
+        if self._win32cred is None:
+            return None
+        try:
+            cred = self._win32cred.CredRead(self._target(key), self._win32cred.CRED_TYPE_GENERIC, 0)
+        except Exception:  # noqa: BLE001 - absent ou illisible : redemander est le repli correct
+            return None
+        blob = cred.get("CredentialBlob") or b""
+        try:
+            return blob.decode("utf-16-le")
+        except UnicodeDecodeError:
+            return None
+
+    def delete_secret(self, key: str) -> None:
+        if self._win32cred is None:
+            return
+        try:
+            self._win32cred.CredDelete(self._target(key), self._win32cred.CRED_TYPE_GENERIC, 0)
+        except Exception:  # noqa: BLE001 - deja absent, ou trousseau indisponible : rien a faire
+            pass
+
+
+def default_credential_store() -> CredentialStore:
+    if os.name == "nt":
+        store = WindowsCredentialStore()
+        if store.is_available():
+            return store
+    return NullCredentialStore()

app/dialogs/session_dialog.py

@@ -11,10 +11,12 @@ from PySide6.QtWidgets import (
 from app.session_manager import (
     Session, SessionStore, BastionConfig, AUTH_AUTO, AUTH_KEY, AUTH_PASSWORD, AUTH_AGENT,
     BASTION_NONE, BASTION_SESSION, BASTION_OPENSSH, BASTION_MANUAL,
+    PASSWORD_STORAGE_NONE, PASSWORD_STORAGE_SECURE,
 )
 from app.key_manager import KeyManager
 from app.openssh.config import load_openssh_hosts
 from app.groups import GroupSettingsStore
+from app.credentials import CredentialStore, NullCredentialStore, session_credential_key
 
 
 class SessionDialog(QDialog):
@@ -25,11 +27,13 @@ class SessionDialog(QDialog):
         self, key_manager: KeyManager, session: Session | None = None,
         parent=None, connect_label: str = "", title: str = "",
         session_store: SessionStore | None = None, group_store: GroupSettingsStore | None = None,
+        credential_store: CredentialStore | None = None,
     ):
         super().__init__(parent)
         self.key_manager = key_manager
         self.session_store = session_store
         self.group_store = group_store
+        self.credential_store = credential_store or NullCredentialStore()
         self.session = session or Session()
         self.quick_mode = bool(connect_label)
         self.setWindowTitle(title or ("Nouvelle session" if session is None else "Modifier la session"))
@@ -94,13 +98,30 @@ class SessionDialog(QDialog):
         form.addRow("Nom :", self.name_edit)
         form.addRow("Dossier :", group_row)
         form.addRow("Tags :", self.tags_edit)
+        self.remember_password_check = QCheckBox("Memoriser le mot de passe de maniere securisee")
+        self.remember_password_check.setChecked(self.session.password_storage == PASSWORD_STORAGE_SECURE)
+        if self.credential_store.is_available():
+            self.remember_password_check.setToolTip(
+                "Stocke dans le trousseau securise du systeme (Windows Credential Manager), "
+                "jamais en clair dans les fichiers de PySSH."
+            )
+        else:
+            self.remember_password_check.setEnabled(False)
+            self.remember_password_check.setChecked(False)
+            self.remember_password_check.setToolTip(
+                "Aucun trousseau securise disponible sur ce systeme : le mot de passe sera "
+                "toujours redemande a la connexion."
+            )
+
         form.addRow("Hote :", self.host_edit)
         form.addRow("Port :", self.port_spin)
         form.addRow("Utilisateur :", self.user_edit)
         form.addRow("Authentification :", self.auth_combo)
         form.addRow("Cle privee :", key_row)
+        form.addRow("", self.remember_password_check)
         form.addRow("Notes :", self.notes_edit)
 
+        self.form = form
         layout.addLayout(form)
         layout.addWidget(self._build_bastion_group())
         layout.addWidget(self._build_keepalive_group())
@@ -141,6 +162,7 @@ class SessionDialog(QDialog):
         is_key_auth = self.auth_combo.currentData() == AUTH_KEY
         self.key_combo.setEnabled(is_key_auth)
         self.browse_key_btn.setEnabled(is_key_auth)
+        self.form.setRowVisible(self.remember_password_check, self.auth_combo.currentData() == AUTH_PASSWORD)
 
     def _browse_key(self) -> None:
         path, _ = QFileDialog.getOpenFileName(self, "Choisir une cle privee")
@@ -439,6 +461,13 @@ class SessionDialog(QDialog):
                 seen.add(tag.lower())
                 tags.append(tag)
         self.session.tags = tags
+        remember = self.auth_combo.currentData() == AUTH_PASSWORD and self.remember_password_check.isChecked()
+        new_storage = PASSWORD_STORAGE_SECURE if remember else PASSWORD_STORAGE_NONE
+        if self.session.password_storage == PASSWORD_STORAGE_SECURE and new_storage == PASSWORD_STORAGE_NONE:
+            # la memorisation vient d'etre desactivee (ou l'authentification changee) :
+            # ne pas laisser un secret perimer dans le trousseau
+            self.credential_store.delete_secret(session_credential_key(self.session.id))
+        self.session.password_storage = new_storage
         self.session.bastion = self._result_bastion()
         self.session.keepalive_enabled = self.keepalive_check.isChecked()
         self.session.keepalive_interval = self.keepalive_interval_spin.value()

app/main_window.py

@@ -25,6 +25,7 @@ from app.theme import THEME_LABELS, apply_theme, current_theme, save_theme
 from app.workspace import WorkspaceStore
 from app.snippets import SnippetStore
 from app.groups import GroupSettingsStore
+from app.credentials import default_credential_store
 from app.controllers.broadcast_manager import BroadcastManager
 from app.controllers.session_controller import SessionController
 from app.controllers.connection_controller import ConnectionController
@@ -46,15 +47,16 @@ class MainWindow(QMainWindow):
         self.workspace_store = WorkspaceStore()
         self.snippet_store = SnippetStore()
         self.group_store = GroupSettingsStore()
+        self.credential_store = default_credential_store()
 
         self.broadcast = BroadcastManager(self._iter_tabs, self)
         self.connection_controller = ConnectionController(
             self.session_store, self.key_manager, self.broadcast,
-            snippet_store=self.snippet_store, parent_widget=self,
+            snippet_store=self.snippet_store, credential_store=self.credential_store, parent_widget=self,
         )
         self.session_controller = SessionController(
             self.session_store, self.key_manager, self.broadcast.button, parent_widget=self,
-            group_store=self.group_store,
+            group_store=self.group_store, credential_store=self.credential_store,
         )
         self.workspace_manager = WorkspaceManager(
             self.workspace_store, self.session_store, self.connection_controller, parent_widget=self,

app/session_manager.py

@@ -16,6 +16,11 @@ AUTH_KEY = "key"         # cle privee explicitement choisie
 AUTH_PASSWORD = "password"
 AUTH_AGENT = "agent"
 
+# Memorisation du mot de passe : jamais dans sessions.json (voir app.credentials),
+# uniquement dans le trousseau securise du systeme, et seulement si demande.
+PASSWORD_STORAGE_NONE = "none"
+PASSWORD_STORAGE_SECURE = "secure"
+
 # Sources possibles d'un jump host (ProxyJump / bastion) - voir BastionConfig.
 BASTION_NONE = "none"        # connexion directe, sans bastion
 BASTION_SESSION = "session"  # reutilise une session PySSH existante (par id)
@@ -81,6 +86,11 @@ class Session:
 
     tags: list[str] = field(default_factory=list)  # ex: ["prod", "docker"]
 
+    # "none" (defaut) : jamais memorise, redemande a chaque connexion.
+    # "secure" : memorise dans le trousseau securise du systeme (voir app.credentials) -
+    # jamais dans ce fichier JSON.
+    password_storage: str = PASSWORD_STORAGE_NONE
+
     def to_dict(self) -> dict:
         return asdict(self)