Add global master password policy setting

Adds MASTER_PASSWORD_POLICY, an optional server-wide master password
policy in the same JSON format as SSO_MASTER_PASSWORD_POLICY. It is
merged with any organization policies (strictest wins) and returned
during login and SSO enrollment, so the clients enforce it for all
users, not only organization members or SSO users.

.env.template

@@ -244,6 +244,11 @@
 ## This setting applies globally to all users.
 # INCOMPLETE_2FA_TIME_LIMIT=3
 
+## Optional global master password policy, enforced for all users in addition to any
+## organization policies. Uses the same JSON format as SSO_MASTER_PASSWORD_POLICY.
+## Note that the Bitwarden clients do not allow a minimum length below 12 characters.
+# MASTER_PASSWORD_POLICY='{"enforceOnLogin":false,"minComplexity":3,"minLength":12,"requireLower":false,"requireNumbers":false,"requireSpecial":false,"requireUpper":false}'
+
 ## Disable icon downloading
 ## Set to true to disable icon downloading in the internal icon service.
 ## This still serves existing icons from $ICON_CACHE_FOLDER, without generating any external

src/api/core/organizations.rs

@@ -1974,8 +1974,8 @@ async fn list_policies_token(org_id: OrganizationId, token: &str, conn: DbConn)
 // Called during the SSO enrollment return the default policy
 #[get("/organizations/00000000-01DC-01DC-01DC-000000000000/policies/master-password", rank = 1)]
 fn get_dummy_master_password_policy() -> JsonResult {
-    let (enabled, data) = match CONFIG.sso_master_password_policy_value() {
-        Some(policy) if CONFIG.sso_enabled() => (true, policy.to_string()),
+    let (enabled, data) = match config_master_password_policy() {
+        Some(policy) => (true, policy.to_string()),
         _ => (false, "null".to_owned()),
     };
     let policy = OrgPolicy::new(FAKE_SSO_IDENTIFIER.into(), OrgPolicyType::MasterPassword, enabled, data);
@@ -1987,8 +1987,8 @@ fn get_dummy_master_password_policy() -> JsonResult {
 async fn get_master_password_policy(org_id: OrganizationId, _headers: OrgMemberHeaders, conn: DbConn) -> JsonResult {
     let policy =
         OrgPolicy::find_by_org_and_type(&org_id, OrgPolicyType::MasterPassword, &conn).await.unwrap_or_else(|| {
-            let (enabled, data) = match CONFIG.sso_master_password_policy_value() {
-                Some(policy) if CONFIG.sso_enabled() => (true, policy.to_string()),
+            let (enabled, data) = match config_master_password_policy() {
+                Some(policy) => (true, policy.to_string()),
                 _ => (false, "null".to_owned()),
             };
 
@@ -1998,6 +1998,17 @@ async fn get_master_password_policy(org_id: OrganizationId, _headers: OrgMemberH
     Ok(Json(policy.to_json()))
 }
 
+// The global policy wins over the SSO one since it applies to all users
+fn config_master_password_policy() -> Option<Value> {
+    CONFIG.master_password_policy_value().or_else(|| {
+        if CONFIG.sso_enabled() {
+            CONFIG.sso_master_password_policy_value()
+        } else {
+            None
+        }
+    })
+}
+
 #[get("/organizations/<org_id>/policies/<pol_type>", rank = 3)]
 async fn get_policy(org_id: OrganizationId, pol_type: i32, headers: AdminHeaders, conn: DbConn) -> JsonResult {
     if org_id != headers.org_id {

src/api/mod.rs

@@ -78,7 +78,7 @@ impl PasswordOrOtpData {
 
 #[expect(clippy::struct_excessive_bools, reason = "Bitwarden clients expect the data in this specific format")]
 #[derive(Debug, Default, Deserialize, Serialize)]
-#[serde(rename_all = "camelCase")]
+#[serde(rename_all = "camelCase", default)]
 pub struct MasterPasswordPolicy {
     min_complexity: Option<u8>,
     min_length: Option<u32>,
@@ -91,7 +91,7 @@ pub struct MasterPasswordPolicy {
 
 // Fetch all valid Master Password Policies and merge them into one with all trues and largest numbers as one policy
 async fn master_password_policy(user: &User, conn: &DbConn) -> Value {
-    let master_password_policies: Vec<MasterPasswordPolicy> =
+    let mut master_password_policies: Vec<MasterPasswordPolicy> =
         OrgPolicy::find_accepted_and_confirmed_by_user_and_active_policy(
             &user.uuid,
             OrgPolicyType::MasterPassword,
@@ -102,6 +102,13 @@ async fn master_password_policy(user: &User, conn: &DbConn) -> Value {
         .filter_map(|p| serde_json::from_str(&p.data).ok())
         .collect();
 
+    // The global policy applies to all users, on top of whatever their organizations require
+    if let Some(global_policy) = CONFIG.master_password_policy_value()
+        && let Ok(global_policy) = serde_json::from_value::<MasterPasswordPolicy>(global_policy)
+    {
+        master_password_policies.push(global_policy);
+    }
+
     let mut mpp_json = if !master_password_policies.is_empty() {
         json!(master_password_policies.into_iter().reduce(|acc, policy| {
             MasterPasswordPolicy {

src/config.rs

@@ -628,6 +628,11 @@ make_config! {
         /// This setting applies globally to all users.
         incomplete_2fa_time_limit: u16, true,   def,    3;
 
+        /// Master password policy |> Optional global master password policy, enforced for all users
+        /// in addition to any organization policies. Uses the same JSON format as the SSO master
+        /// password policy. Ex format: '{"enforceOnLogin":false,"minComplexity":3,"minLength":12,"requireLower":false,"requireNumbers":false,"requireSpecial":false,"requireUpper":false}'
+        master_password_policy: String, true,   option;
+
         /// Disable icon downloads |> Set to true to disable icon downloading in the internal icon service.
         /// This still serves existing icons from $ICON_CACHE_FOLDER, without generating any external
         /// network requests. $ICON_CACHE_TTL must also be set to 0; otherwise, the existing icons
@@ -1154,9 +1159,11 @@ fn validate_config(cfg: &ConfigItems, on_update: bool) -> Result<(), Error> {
 
         validate_internal_sso_issuer_url(&cfg.sso_authority)?;
         validate_internal_sso_redirect_url(&cfg.sso_callback_path)?;
-        validate_sso_master_password_policy(cfg.sso_master_password_policy.as_ref())?;
+        validate_master_password_policy("sso_master_password_policy", cfg.sso_master_password_policy.as_ref())?;
     }
 
+    validate_master_password_policy("master_password_policy", cfg.master_password_policy.as_ref())?;
+
     if cfg._enable_yubico {
         if cfg.yubico_client_id.is_some() != cfg.yubico_secret_key.is_some() {
             err!("Both `YUBICO_CLIENT_ID` and `YUBICO_SECRET_KEY` must be set for Yubikey OTP support")
@@ -1385,17 +1392,18 @@ fn validate_internal_sso_redirect_url(sso_callback_path: &String) -> Result<open
     }
 }
 
-fn validate_sso_master_password_policy(
-    sso_master_password_policy: Option<&String>,
+fn validate_master_password_policy(
+    setting_name: &str,
+    master_password_policy: Option<&String>,
 ) -> Result<Option<serde_json::Value>, Error> {
-    let policy = sso_master_password_policy.as_ref().map(|mpp| serde_json::from_str::<serde_json::Value>(mpp));
+    let policy = master_password_policy.as_ref().map(|mpp| serde_json::from_str::<serde_json::Value>(mpp));
 
     match policy {
         None => Ok(None),
         Some(Ok(jsobject @ serde_json::Value::Object(_))) => Ok(Some(jsobject)),
-        Some(Ok(_)) => err!("Invalid sso_master_password_policy: parsed value is not a JSON object"),
+        Some(Ok(_)) => err!(format!("Invalid {setting_name}: parsed value is not a JSON object")),
         Some(Err(error)) => {
-            err!(format!("Invalid sso_master_password_policy ({error}), Ensure that it's correctly escaped with ''"))
+            err!(format!("Invalid {setting_name} ({error}), Ensure that it's correctly escaped with ''"))
         }
     }
 }
@@ -1767,7 +1775,13 @@ impl Config {
     }
 
     pub fn sso_master_password_policy_value(&self) -> Option<serde_json::Value> {
-        validate_sso_master_password_policy(self.sso_master_password_policy().as_ref()).ok().flatten()
+        validate_master_password_policy("sso_master_password_policy", self.sso_master_password_policy().as_ref())
+            .ok()
+            .flatten()
+    }
+
+    pub fn master_password_policy_value(&self) -> Option<serde_json::Value> {
+        validate_master_password_policy("master_password_policy", self.master_password_policy().as_ref()).ok().flatten()
     }
 
     pub fn sso_scopes_vec(&self) -> Vec<String> {