T8344: Preserve symlinks when copying config to/from TPM encrypted volume

shutil.copytree() defaults to symlinks=False, so it recurses into
symlinked directories and recreates them as real directories instead
of preserving the symlink.
cloud-init creates /opt/vyatta/etc/config/cloud/instance as a symlink
to instances/i-<id>. Enabling/disabling config encryption copied this
tree with copytree() and silently turned that symlink into a real
directory, causing cloud-init to fail on later runs with:
    IsADirectoryError: [Errno 21] Is a directory: '.../cloud/instance'
Pass symlinks=True to preserve symlinks during the copy.

1 files changed, 6 insertions, 2 deletions

diff --git a/src/helpers/vyos-config-encrypt.py b/src/helpers/vyos-config-encrypt.py
index e035040e1..876a835ec 100755
--- a/src/helpers/vyos-config-encrypt.py
+++ b/src/helpers/vyos-config-encrypt.py
@@ -122,7 +122,9 @@ def encrypt_config(key, recovery_key=None, is_tpm=True):
         cmd(f'mount /dev/mapper/vyos_config {d}')
 
         # Move mount_path to encrypted volume
-        shutil.copytree(mount_path, d, copy_function=shutil.move, dirs_exist_ok=True)
+        shutil.copytree(
+            mount_path, d, symlinks=True, copy_function=shutil.move, dirs_exist_ok=True
+        )
         cmd(f'chgrp -R vyattacfg {d}')
         cmd(f'umount {d}')
 
@@ -207,7 +209,9 @@ def decrypt_config(key):
         cmd(f'mount /dev/mapper/vyos_config {d}')
 
         # Move encrypted volume to /opt/vyatta/etc/config
-        shutil.copytree(d, mount_path, copy_function=shutil.move, dirs_exist_ok=True)
+        shutil.copytree(
+            d, mount_path, symlinks=True, copy_function=shutil.move, dirs_exist_ok=True
+        )
         cmd(f'chgrp -R vyattacfg {mount_path}')
 
         cmd(f'umount {d}')