composefs-backend: Fix image pull from registry

skopeo (in composefs-rs) doesn't understand the transport "registry:",
so we convert it to "docker://" when passing it to skopeo

Signed-off-by: Pragyan Poudyal <[email protected]>

Author: Johan-Liebert1

crates/lib/src/bootc_composefs/repo.rs

@@ -54,6 +54,25 @@ pub(crate) async fn initialize_composefs_repository(
     .await
 }
 
+/// skopeo (in composefs-rs) doesn't understand "registry:"
+/// This function will convert it to "docker://" and return the image ref
+///
+/// Ex
+/// docker://quay.io/some-image
+/// containers-storage:some-image
+pub(crate) fn get_imgref(transport: &String, image: &String) -> String {
+    let img = image.strip_prefix(":").unwrap_or(&image);
+    let transport = transport.strip_suffix(":").unwrap_or(&transport);
+
+    let final_imgref = if transport == "registry" {
+        format!("docker://{img}")
+    } else {
+        format!("{transport}:{img}")
+    };
+
+    final_imgref
+}
+
 /// Pulls the `image` from `transport` into a composefs repository at /sysroot
 /// Checks for boot entries in the image and returns them
 #[context("Pulling composefs repository")]
@@ -70,10 +89,13 @@ pub(crate) async fn pull_composefs_repo(
 
     let repo = open_composefs_repo(&rootfs_dir).context("Opening compoesfs repo")?;
 
-    let (id, verity) =
-        composefs_oci_pull(&Arc::new(repo), &format!("{transport}:{image}"), None, None)
-            .await
-            .context("Pulling composefs repo")?;
+    let final_imgref = get_imgref(transport, image);
+
+    tracing::debug!("Image to pull {final_imgref}");
+
+    let (id, verity) = composefs_oci_pull(&Arc::new(repo), &final_imgref, None, None)
+        .await
+        .context("Pulling composefs repo")?;
 
     tracing::info!("id: {}, verity: {}", hex::encode(id), verity.to_hex());
 

crates/lib/src/bootc_composefs/state.rs

@@ -18,6 +18,7 @@ use rustix::{
 };
 
 use crate::bootc_composefs::boot::BootType;
+use crate::bootc_composefs::repo::get_imgref;
 use crate::bootc_composefs::status::get_sorted_type1_boot_entries;
 use crate::parsers::bls_config::BLSConfigType;
 use crate::{
@@ -132,9 +133,12 @@ pub(crate) fn write_composefs_state(
         ..
     } = &imgref;
 
+    let imgref = get_imgref(&transport, &image_name);
+
     let mut config = tini::Ini::new().section("origin").item(
         ORIGIN_CONTAINER,
-        format!("ostree-unverified-image:{transport}{image_name}"),
+        // TODO (Johan-Liebert1): The image won't always be unverified
+        format!("ostree-unverified-image:{imgref}"),
     );
 
     config = config