diff --git a/src/lib.rs b/src/lib.rs
index 0a1239b..ed94c9c 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -8,7 +8,7 @@ use std::sync::{Arc, Condvar, Mutex};
 
 use proxmox_lang::try_block;
 
-use pbs_api_types::{Authid, BackupDir, BackupNamespace, BackupType, CryptMode};
+use pbs_api_types::{Authid, BackupArchiveName, BackupDir, BackupNamespace, BackupType, CryptMode};
 use pbs_client::BackupRepository;
 
 pub mod capi_types;
@@ -979,6 +979,7 @@ pub extern "C" fn proxmox_restore_image(
     let result: Result<_, Error> = try_block!({
         let archive_name = tools::utf8_c_string(archive_name)?
             .ok_or_else(|| format_err!("archive_name must not be NULL"))?;
+        let archive_name: BackupArchiveName = archive_name.parse()?;
 
         let write_data_callback = move |offset: u64, data: &[u8]| {
             callback(callback_data, offset, data.as_ptr(), data.len() as u64)
@@ -988,7 +989,7 @@ pub extern "C" fn proxmox_restore_image(
             move |offset: u64, len: u64| callback(callback_data, offset, std::ptr::null(), len);
 
         proxmox_async::runtime::block_on(restore_task.restore_image(
-            archive_name,
+            &archive_name,
             write_data_callback,
             write_zero_callback,
             verbose,
@@ -1051,9 +1052,16 @@ pub extern "C" fn proxmox_restore_open_image_async(
 
     param_not_null!(archive_name, callback_info);
     let archive_name = unsafe { tools::utf8_c_string_lossy_non_null(archive_name) };
+    let archive_name = match archive_name.parse() {
+        Ok(archive_name) => archive_name,
+        Err(err) => {
+            callback_info.send_result(Err(err));
+            return;
+        }
+    };
 
     restore_task.runtime().spawn(async move {
-        let result = match restore_task.open_image(archive_name).await {
+        let result = match restore_task.open_image(&archive_name).await {
             Ok(res) => Ok(res as i32),
             Err(err) => Err(err),
         };
diff --git a/src/restore.rs b/src/restore.rs
index d3818e9..a879b99 100644
--- a/src/restore.rs
+++ b/src/restore.rs
@@ -3,6 +3,7 @@ use std::sync::{Arc, Mutex};
 
 use anyhow::{bail, format_err, Error};
 use once_cell::sync::OnceCell;
+use pbs_api_types::BackupArchiveName;
 use tokio::runtime::Runtime;
 
 use proxmox_async::runtime::get_runtime_with_builder;
@@ -19,7 +20,6 @@ use pbs_tools::crypt_config::CryptConfig;
 
 use super::BackupSetup;
 use crate::capi_types::DataPointer;
-use crate::commands::archive_name;
 use crate::registry::Registry;
 use crate::shared_cache::get_shared_chunk_cache;
 
@@ -119,12 +119,11 @@ impl RestoreTask {
 
     pub async fn restore_image(
         &self,
-        archive_str: String,
+        archive_name: &BackupArchiveName,
         write_data_callback: impl Fn(u64, &[u8]) -> i32,
         write_zero_callback: impl Fn(u64, u64) -> i32,
         verbose: bool,
     ) -> Result<(), Error> {
-        let archive_name = archive_name(&archive_str)?;
         if verbose {
             eprintln!("download and verify backup index");
         }
@@ -218,8 +217,7 @@ impl RestoreTask {
         Ok(info.archive_size)
     }
 
-    pub async fn open_image(&self, archive_str: String) -> Result<u8, Error> {
-        let archive_name = archive_name(&archive_str)?;
+    pub async fn open_image(&self, archive_name: &BackupArchiveName) -> Result<u8, Error> {
         let client = match self.client.get() {
             Some(reader) => Arc::clone(reader),
             None => bail!("not connected"),
@@ -254,7 +252,7 @@ impl RestoreTask {
 
         let info = ImageAccessInfo {
             archive_size,
-            _archive_name: archive_str,
+            _archive_name: archive_name.to_string(),
             // useful to debug
             reader,
         };