sysext: support distribution-independent extensions using ID=_any

A sysext image that merely contains static binaries has no dependency
on the host distribution and should be able to be used anywhere.
Support the special '_any' value for the ID field in the extension to
opt-out of ID and VERSION_ID/SYSEXT_LEVEL matching.

See https://github.com/systemd/systemd/issues/24061
This commit is contained in:
Kai Lueke 2022-08-09 13:34:18 +02:00
parent 78fa2f91d2
commit ab4d43c54e
4 changed files with 21 additions and 4 deletions

View File

@ -115,8 +115,9 @@
<para>A simple mechanism for version compatibility is enforced: a system extension image must carry a
<filename>/usr/lib/extension-release.d/extension-release.<replaceable>$name</replaceable></filename>
file, which must match its image name, that is compared with the host <filename>os-release</filename>
file: the contained <varname>ID=</varname> fields have to match, as well as the
<varname>SYSEXT_LEVEL=</varname> field (if defined). If the latter is not defined, the
file: the contained <varname>ID=</varname> fields have to match unless <literal>_any</literal> is set
for the extension. If the extension <varname>ID=</varname> is not <literal>_any</literal>, the
<varname>SYSEXT_LEVEL=</varname> field (if defined) has to match. If the latter is not defined, the
<varname>VERSION_ID=</varname> field has to match instead. System extensions should not ship a
<filename>/usr/lib/os-release</filename> file (as that would be merged into the host
<filename>/usr/</filename> tree, overriding the host OS version data, which is not desirable). The

View File

@ -50,11 +50,18 @@ int extension_release_validate(
extension_release_id = strv_env_pairs_get(extension_release, "ID");
if (isempty(extension_release_id)) {
log_debug("Extension '%s' does not contain ID in extension-release but requested to match '%s'",
log_debug("Extension '%s' does not contain ID in extension-release but requested to match '%s' or be '_any'",
name, host_os_release_id);
return 0;
}
/* A sysext with no host OS dependency (static binaries or scripts) can match
* '_any' host OS, and VERSION_ID or SYSEXT_LEVEL are not required anywhere */
if (streq(extension_release_id, "_any")) {
log_debug("Extension '%s' matches '_any' OS.", name);
return 1;
}
if (!streq(host_os_release_id, extension_release_id)) {
log_debug("Extension '%s' is for OS '%s', but deployed on top of '%s'.",
name, extension_release_id, host_os_release_id);

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@ -712,6 +712,12 @@ EOF
chmod +x "$initdir/opt/script1.sh"
echo MARKER=1 >"$initdir/usr/lib/systemd/system/other_file"
mksquashfs "$initdir" "$oldinitdir/usr/share/app1.raw" -noappend
export initdir="$TESTDIR/app-nodistro"
mkdir -p "$initdir/usr/lib/extension-release.d" "$initdir/usr/lib/systemd/system"
( echo "ID=_any" ) >"$initdir/usr/lib/extension-release.d/extension-release.app-nodistro"
echo MARKER=1 >"$initdir/usr/lib/systemd/system/some_file"
mksquashfs "$initdir" "$oldinitdir/usr/share/app-nodistro.raw" -noappend
)
}

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@ -305,6 +305,7 @@ systemd-run -P --property ExtensionImages="/usr/share/app0.raw /usr/share/app1.r
systemd-run -P --property ExtensionImages="/usr/share/app0.raw /usr/share/app1.raw" --property RootImage="${image}.raw" cat /usr/lib/systemd/system/some_file | grep -q -F "MARKER=1"
systemd-run -P --property ExtensionImages="/usr/share/app0.raw /usr/share/app1.raw" --property RootImage="${image}.raw" cat /opt/script1.sh | grep -q -F "extension-release.app2"
systemd-run -P --property ExtensionImages="/usr/share/app0.raw /usr/share/app1.raw" --property RootImage="${image}.raw" cat /usr/lib/systemd/system/other_file | grep -q -F "MARKER=1"
systemd-run -P --property ExtensionImages=/usr/share/app-nodistro.raw --property RootImage="${image}.raw" cat /usr/lib/systemd/system/some_file | grep -q -F "MARKER=1"
cat >/run/systemd/system/testservice-50e.service <<EOF
[Service]
MountAPIVFS=yes
@ -323,17 +324,19 @@ systemctl start testservice-50e.service
systemctl is-active testservice-50e.service
# ExtensionDirectories will set up an overlay
mkdir -p "${image_dir}/app0" "${image_dir}/app1"
mkdir -p "${image_dir}/app0" "${image_dir}/app1" "${image_dir}/app-nodistro"
systemd-run -P --property ExtensionDirectories="${image_dir}/nonexistent" --property RootImage="${image}.raw" cat /opt/script0.sh && { echo 'unexpected success'; exit 1; }
systemd-run -P --property ExtensionDirectories="${image_dir}/app0" --property RootImage="${image}.raw" cat /opt/script0.sh && { echo 'unexpected success'; exit 1; }
systemd-dissect --mount /usr/share/app0.raw "${image_dir}/app0"
systemd-dissect --mount /usr/share/app1.raw "${image_dir}/app1"
systemd-dissect --mount /usr/share/app-nodistro.raw "${image_dir}/app-nodistro"
systemd-run -P --property ExtensionDirectories="${image_dir}/app0" --property RootImage="${image}.raw" cat /opt/script0.sh | grep -q -F "extension-release.app0"
systemd-run -P --property ExtensionDirectories="${image_dir}/app0" --property RootImage="${image}.raw" cat /usr/lib/systemd/system/some_file | grep -q -F "MARKER=1"
systemd-run -P --property ExtensionDirectories="${image_dir}/app0 ${image_dir}/app1" --property RootImage="${image}.raw" cat /opt/script0.sh | grep -q -F "extension-release.app0"
systemd-run -P --property ExtensionDirectories="${image_dir}/app0 ${image_dir}/app1" --property RootImage="${image}.raw" cat /usr/lib/systemd/system/some_file | grep -q -F "MARKER=1"
systemd-run -P --property ExtensionDirectories="${image_dir}/app0 ${image_dir}/app1" --property RootImage="${image}.raw" cat /opt/script1.sh | grep -q -F "extension-release.app2"
systemd-run -P --property ExtensionDirectories="${image_dir}/app0 ${image_dir}/app1" --property RootImage="${image}.raw" cat /usr/lib/systemd/system/other_file | grep -q -F "MARKER=1"
systemd-run -P --property ExtensionDirectories="${image_dir}/app-nodistro" --property RootImage="${image}.raw" cat /usr/lib/systemd/system/some_file | grep -q -F "MARKER=1"
cat >/run/systemd/system/testservice-50f.service <<EOF
[Service]
MountAPIVFS=yes