Add ostree admin post-copy command

This command will apply fs-verity on all objects that need it and
needs to be called when an ostree deployment has been copied on a
file-by-file basis, which would loose information such as fs-verity.

This is needed by osbuild which works by creating the final image in a
rootfs, and then separately copying that rootfs file-by-file to a
loopback mounted filesystem image.

Makefile-libostree.am

@@ -175,9 +175,9 @@ endif # USE_GPGME
 symbol_files = $(top_srcdir)/src/libostree/libostree-released.sym
 
 # Uncomment this include when adding new development symbols.
-#if BUILDOPT_IS_DEVEL_BUILD
-#symbol_files += $(top_srcdir)/src/libostree/libostree-devel.sym
-#endif
+if BUILDOPT_IS_DEVEL_BUILD
+symbol_files += $(top_srcdir)/src/libostree/libostree-devel.sym
+endif
 
 # http://blog.jgc.org/2007/06/escaping-comma-and-space-in-gnu-make.html
 wl_versionscript_arg = -Wl,--version-script=

Makefile-man.am

@@ -29,7 +29,7 @@ ostree-admin-config-diff.1 ostree-admin-deploy.1			\
 ostree-admin-init-fs.1 ostree-admin-instutil.1 ostree-admin-stateroot-init.1 ostree-admin-os-init.1	\
 ostree-admin-status.1 ostree-admin-set-origin.1 ostree-admin-switch.1	\
 ostree-admin-undeploy.1 ostree-admin-upgrade.1 ostree-admin-unlock.1	\
-ostree-admin-pin.1 ostree-admin-set-default.1 \
+ostree-admin-pin.1 ostree-admin-post-copy.1 ostree-admin-set-default.1 \
 ostree-admin.1 ostree-cat.1 ostree-checkout.1 ostree-checksum.1		\
 ostree-commit.1 ostree-create-usb.1 ostree-export.1 \
 ostree-config.1 ostree-diff.1 ostree-find-remotes.1 ostree-fsck.1 \

Makefile-ostree.am

@@ -81,6 +81,7 @@ ostree_SOURCES += \
 	src/ostree/ot-admin-builtin-status.c \
 	src/ostree/ot-admin-builtin-switch.c \
 	src/ostree/ot-admin-builtin-pin.c \
+	src/ostree/ot-admin-builtin-post-copy.c \
 	src/ostree/ot-admin-builtin-upgrade.c \
 	src/ostree/ot-admin-builtin-unlock.c \
 	src/ostree/ot-admin-builtins.h \

man/index.xml

@@ -56,6 +56,10 @@ License along with this library. If not, see <https://www.gnu.org/licenses/>.
         <refentrytitle>ostree-admin-pin</refentrytitle><manvolnum>1</manvolnum>
     </citerefentry></primaryie></indexentry>
 
+    <indexentry><primaryie><citerefentry>
+        <refentrytitle>ostree-admin-post-copy</refentrytitle><manvolnum>1</manvolnum>
+    </citerefentry></primaryie></indexentry>
+
     <indexentry><primaryie><citerefentry>
         <refentrytitle>ostree-admin-set-origin</refentrytitle><manvolnum>1</manvolnum>
     </citerefentry></primaryie></indexentry>

man/ostree-admin.xml

@@ -72,6 +72,7 @@ License along with this library. If not, see <https://www.gnu.org/licenses/>.
             <listitem><para><command>instutil</command></para></listitem>
             <listitem><para><command>os-init</command></para></listitem>
             <listitem><para><command>pin</command></para></listitem>
+            <listitem><para><command>post-copy</command></para></listitem>
             <listitem><para><command>set-origin</command></para></listitem>
             <listitem><para><command>status</command></para></listitem>
             <listitem><para><command>switch</command></para></listitem>

src/libostree/libostree-devel.sym

@@ -29,3 +29,8 @@ global:
   someostree_symbol_deleteme;
 } LIBOSTREE_2021.$LASTSTABLE;
 */
+
+LIBOSTREE_2023.11 {
+global:
+  ostree_sysroot_update_post_copy;
+} LIBOSTREE_2023.4;

src/libostree/ostree-repo-private.h

@@ -412,6 +412,9 @@ gboolean _ostree_tmpf_fsverity_core (GLnxTmpfile *tmpf, _OstreeFeatureSupport fs
 gboolean _ostree_tmpf_fsverity (OstreeRepo *self, GLnxTmpfile *tmpf, GBytes *signature,
                                 GError **error);
 
+gboolean _ostree_ensure_fsverity (OstreeRepo *self, gboolean allow_enoent, int dirfd,
+                                  const char *path, gboolean *supported, GError **error);
+
 gboolean _ostree_repo_verify_bindings (const char *collection_id, const char *ref_name,
                                        GVariant *commit, GError **error);
 

src/libostree/ostree-repo-verity.c

@@ -102,28 +102,14 @@ _ostree_repo_parse_fsverity_config (OstreeRepo *self, GError **error)
   return TRUE;
 }
 
-/* Wrapper around the fsverity ioctl, compressing the result to
- * "success, unsupported or error".  This is used for /boot where
- * we enable verity if supported.
- * */
-gboolean
-_ostree_tmpf_fsverity_core (GLnxTmpfile *tmpf, _OstreeFeatureSupport fsverity_requested,
-                            GBytes *signature, gboolean *supported, GError **error)
+static gboolean
+_ostree_fsverity_enable (int fd, gboolean allow_existing, gboolean *supported, GBytes *signature,
+                         GError **error)
 {
-  /* Set this by default to simplify the code below */
   if (supported)
     *supported = FALSE;
 
-  if (fsverity_requested == _OSTREE_FEATURE_NO)
-    return TRUE;
-
 #ifdef HAVE_LINUX_FSVERITY_H
-  GLNX_AUTO_PREFIX_ERROR ("fsverity", error);
-
-  /* fs-verity requires a read-only file descriptor */
-  if (!glnx_tmpfile_reopen_rdonly (tmpf, error))
-    return FALSE;
-
   struct fsverity_enable_arg arg = {
     0,
   };
@@ -135,21 +121,50 @@ _ostree_tmpf_fsverity_core (GLnxTmpfile *tmpf, _OstreeFeatureSupport fsverity_re
   arg.sig_size = signature ? g_bytes_get_size (signature) : 0;
   arg.sig_ptr = signature ? (guint64)g_bytes_get_data (signature, NULL) : 0;
 
-  if (ioctl (tmpf->fd, FS_IOC_ENABLE_VERITY, &arg) < 0)
+  if (ioctl (fd, FS_IOC_ENABLE_VERITY, &arg) < 0)
     {
       switch (errno)
         {
         case ENOTTY:
         case EOPNOTSUPP:
           return TRUE;
         default:
-          return glnx_throw_errno_prefix (error, "ioctl(FS_IOC_ENABLE_VERITY)");
+          if (errno != EEXIST || !allow_existing)
+            return glnx_throw_errno_prefix (error, "ioctl(FS_IOC_ENABLE_VERITY)");
         }
     }
 
   if (supported)
     *supported = TRUE;
 #endif
+
+  return TRUE;
+}
+
+/* Wrapper around the fsverity ioctl, compressing the result to
+ * "success, unsupported or error".  This is used for /boot where
+ * we enable verity if supported.
+ * */
+gboolean
+_ostree_tmpf_fsverity_core (GLnxTmpfile *tmpf, _OstreeFeatureSupport fsverity_requested,
+                            GBytes *signature, gboolean *supported, GError **error)
+{
+  if (fsverity_requested == _OSTREE_FEATURE_NO)
+    {
+      if (supported)
+        *supported = FALSE;
+      return TRUE;
+    }
+
+  GLNX_AUTO_PREFIX_ERROR ("fsverity", error);
+
+  /* fs-verity requires a read-only file descriptor */
+  if (!glnx_tmpfile_reopen_rdonly (tmpf, error))
+    return FALSE;
+
+  if (!_ostree_fsverity_enable (tmpf->fd, FALSE, supported, signature, error))
+    return FALSE;
+
   return TRUE;
 }
 
@@ -206,3 +221,27 @@ _ostree_tmpf_fsverity (OstreeRepo *self, GLnxTmpfile *tmpf, GBytes *signature, G
 #endif
   return TRUE;
 }
+
+gboolean
+_ostree_ensure_fsverity (OstreeRepo *self, gboolean allow_enoent, int dirfd, const char *path,
+                         gboolean *supported, GError **error)
+{
+  glnx_autofd int fd = -1;
+
+  if (!ot_openat_ignore_enoent (dirfd, path, &fd, error))
+    return FALSE;
+
+  if (fd == -1 && !allow_enoent)
+    return glnx_throw (error, "Unexpectedly missing file '%s', can't enable fs-verity", path);
+
+  if (fd != -1)
+    {
+      if (!_ostree_fsverity_enable (fd, TRUE, supported, NULL, error))
+        return FALSE;
+
+      if (!supported && self->fs_verity_wanted == _OSTREE_FEATURE_YES)
+        return glnx_throw (error, "fsverity required but filesystem does not support it");
+    }
+
+  return TRUE;
+}

src/libostree/ostree-sysroot-cleanup.c

@@ -19,8 +19,10 @@
 
 #include "config.h"
 
+#include "ostree-core-private.h"
 #include "ostree-linuxfsutil.h"
 #include "ostree-repo-private.h"
+#include "otcore.h"
 #include "otutil.h"
 
 #include "ostree-sysroot-private.h"
@@ -573,3 +575,70 @@ _ostree_sysroot_cleanup_internal (OstreeSysroot *self, gboolean do_prune_repo,
 
   return TRUE;
 }
+
+/**
+ * ostree_sysroot_update_post_copy:
+ * @self: Sysroot
+ * @error: Error
+ *
+ * Update a sysroot as needed after having copied it into place using file-level
+ * operations. This enables options like fs-verity on the required files that may
+ * have been lost during the copy.
+ *
+ * Since: 2023.11
+ */
+gboolean
+ostree_sysroot_update_post_copy (OstreeSysroot *self, GCancellable *cancellable, GError **error)
+{
+  OstreeRepo *repo = ostree_sysroot_repo (self);
+
+  if (repo->fs_verity_wanted != _OSTREE_FEATURE_NO)
+    {
+      g_autoptr (GHashTable) objects
+          = ostree_repo_list_objects_set (repo, OSTREE_REPO_LIST_OBJECTS_LOOSE, cancellable, error);
+      if (objects == NULL)
+        return FALSE;
+
+      GLNX_HASH_TABLE_FOREACH (objects, GVariant *, key)
+        {
+          const char *checksum;
+          OstreeObjectType objtype;
+
+          ostree_object_name_deserialize (key, &checksum, &objtype);
+
+          char loose_path_buf[_OSTREE_LOOSE_PATH_MAX];
+          _ostree_loose_path (loose_path_buf, checksum, objtype, repo->mode);
+
+          gboolean supported;
+          if (!_ostree_ensure_fsverity (repo, FALSE, repo->objects_dir_fd, loose_path_buf,
+                                        &supported, error))
+            return FALSE;
+
+          if (!supported)
+            break; /* If not supported, skip rest */
+        }
+
+      g_autoptr (GPtrArray) all_deployment_dirs = NULL;
+      if (!list_all_deployment_directories (self, &all_deployment_dirs, cancellable, error))
+        return FALSE;
+      g_assert (all_deployment_dirs); /* Pacify static analysis */
+      for (guint i = 0; i < all_deployment_dirs->len; i++)
+        {
+          OstreeDeployment *deployment = all_deployment_dirs->pdata[i];
+          g_autofree char *deployment_path
+              = ostree_sysroot_get_deployment_dirpath (self, deployment);
+
+          g_autofree char *cfs_file
+              = g_build_filename (deployment_path, OSTREE_COMPOSEFS_NAME, NULL);
+
+          gboolean supported;
+          if (!_ostree_ensure_fsverity (repo, TRUE, self->sysroot_fd, cfs_file, &supported, error))
+            return FALSE;
+
+          if (!supported)
+            break; /* If not supported, skip rest */
+        }
+    }
+
+  return TRUE;
+}

src/libostree/ostree-sysroot.h

@@ -237,6 +237,10 @@ void ostree_sysroot_query_deployments_for (OstreeSysroot *self, const char *osna
 _OSTREE_PUBLIC
 OstreeDeployment *ostree_sysroot_get_merge_deployment (OstreeSysroot *self, const char *osname);
 
+_OSTREE_PUBLIC
+gboolean ostree_sysroot_update_post_copy (OstreeSysroot *self, GCancellable *cancellable,
+                                          GError **error);
+
 _OSTREE_PUBLIC
 GKeyFile *ostree_sysroot_origin_new_from_refspec (OstreeSysroot *self, const char *refspec);
 

src/ostree/ot-admin-builtin-post-copy.c

@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2012,2013 Colin Walters <[email protected]>
+ *
+ * SPDX-License-Identifier: LGPL-2.0+
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * Author: Colin Walters <[email protected]>
+ */
+
+#include "config.h"
+
+#include "ostree-sysroot-private.h"
+
+#include "ostree.h"
+#include "ot-admin-builtins.h"
+#include "ot-admin-functions.h"
+#include "ot-main.h"
+#include "otutil.h"
+
+#include <glib/gi18n.h>
+
+static GOptionEntry options[] = { { NULL } };
+
+gboolean
+ot_admin_builtin_post_copy (int argc, char **argv, OstreeCommandInvocation *invocation,
+                            GCancellable *cancellable, GError **error)
+{
+  g_autoptr (GOptionContext) context = g_option_context_new ("");
+
+  g_autoptr (OstreeSysroot) sysroot = NULL;
+  if (!ostree_admin_option_context_parse (context, options, &argc, &argv,
+                                          OSTREE_ADMIN_BUILTIN_FLAG_SUPERUSER, invocation, &sysroot,
+                                          cancellable, error))
+    return FALSE;
+
+  if (!ostree_sysroot_update_post_copy (sysroot, cancellable, error))
+    return FALSE;
+
+  return TRUE;
+}

src/ostree/ot-admin-builtins.h

@@ -48,6 +48,7 @@ BUILTINPROTO (diff);
 BUILTINPROTO (switch);
 BUILTINPROTO (upgrade);
 BUILTINPROTO (kargs);
+BUILTINPROTO (post_copy);
 
 #undef BUILTINPROTO
 

src/ostree/ot-builtin-admin.c

@@ -51,6 +51,8 @@ static OstreeCommand admin_subcommands[] = {
     "Initialize empty state for given operating system" },
   { "pin", OSTREE_BUILTIN_FLAG_NO_REPO, ot_admin_builtin_pin,
     "Change the \"pinning\" state of a deployment" },
+  { "post-copy", OSTREE_BUILTIN_FLAG_NO_REPO, ot_admin_builtin_post_copy,
+    "Update the repo and deployments as needed after a copy" },
   { "set-origin", OSTREE_BUILTIN_FLAG_NO_REPO, ot_admin_builtin_set_origin,
     "Set Origin and create a new origin file" },
   { "status", OSTREE_BUILTIN_FLAG_NO_REPO, ot_admin_builtin_status, "List deployments" },