[Web 2026.9.0] Support new Emergency Access password payload (#7746)

* Support new emergency access password payload

* Apply PR 7747 review changes to emergency access

* Add Playwright test for emergency access takeover

src/api/core/emergency_access.rs

@@ -6,7 +6,10 @@ use crate::{
     CONFIG,
     api::{
         EmptyResult, JsonResult,
-        core::{CipherSyncData, CipherSyncType},
+        core::{
+            CipherSyncData, CipherSyncType,
+            accounts::{AuthenticationData, UnlockData},
+        },
     },
     auth::{Headers, decode_emergency_access_invite},
     db::{
@@ -615,6 +618,7 @@ async fn takeover_emergency_access(emer_id: EmergencyAccessId, headers: Headers,
         "kdfMemory": grantor_user.client_kdf_memory,
         "kdfParallelism": grantor_user.client_kdf_parallelism,
         "keyEncrypted": &emergency_access.key_encrypted,
+        "salt": grantor_user.master_password_salt(),
         "object": "emergencyAccessTakeover",
     });
 
@@ -624,8 +628,13 @@ async fn takeover_emergency_access(emer_id: EmergencyAccessId, headers: Headers,
 #[derive(Deserialize)]
 #[serde(rename_all = "camelCase")]
 struct EmergencyAccessPasswordData {
-    new_master_password_hash: String,
-    key: String,
+    // Legacy payload
+    new_master_password_hash: Option<String>,
+    key: Option<String>,
+
+    // Current payload
+    authentication_data: Option<AuthenticationData>,
+    unlock_data: Option<UnlockData>,
 }
 
 #[post("/emergency-access/<emer_id>/password", data = "<data>")]
@@ -638,8 +647,6 @@ async fn password_emergency_access(
     check_emergency_access_enabled()?;
 
     let data: EmergencyAccessPasswordData = data.into_inner();
-    let new_master_password_hash = &data.new_master_password_hash;
-    //let key = &data.Key;
 
     let requesting_user = headers.user;
     let Some(emergency_access) =
@@ -656,8 +663,23 @@ async fn password_emergency_access(
         err!("Grantor user not found.")
     };
 
+    let (new_master_password_hash, new_key) =
+        if let (Some(authentication_data), Some(unlock_data)) = (data.authentication_data, data.unlock_data) {
+            authentication_data.check(&grantor_user, &unlock_data)?;
+
+            if !authentication_data.kdf.matches_user(&grantor_user) {
+                err!("KDF settings do not match the grantor account")
+            }
+
+            (authentication_data.master_password_authentication_hash, unlock_data.master_key_wrapped_user_key)
+        } else if let (Some(new_master_password_hash), Some(new_key)) = (data.new_master_password_hash, data.key) {
+            (new_master_password_hash, new_key)
+        } else {
+            err!("Invalid request!")
+        };
+
     // change grantor_user password
-    grantor_user.set_password(new_master_password_hash, Some(data.key), true, None, &conn).await?;
+    grantor_user.set_password(&new_master_password_hash, Some(new_key), true, None, &conn).await?;
     grantor_user.save(&conn).await?;
 
     // Disable TwoFactor providers since they will otherwise block logins