fix: ensure landscape homedir and broker.bpickle are owned by landscape (LP: #2065879)

[Perfect5th]

This addresses an issue where setting umask 027 would not allow for registration.

[Perfect5th]

Testing steps are pretty clearly laid out in the body of https://bugs.launchpad.net/landscape-client/+bug/2065879 but I'll copy them here to be safe.

How to reproduce:

# umask 027
# landscape-config --computer-title test--account-name standalone --url https://test.net/message-system --ping-url http://test.net/> ping --ssl-public-key /etc/landscape/test.pem

Fails with:

Traceback (most recent call last):

Failure: twisted.internet.error.ConnectError: An error occurred while connecting: 2: No such file or directory.

# ls -l /var/lib/landscape/client/
total 52
drwxr-xr-x 2 landscape landscape 4096 May 16 13:53 annotations.d
-rw-r----- 1 root root 33 May 16 13:54 broker.bpickle
-rw-r----- 1 root root 47 May 16 13:53 broker.bpickle.old
drwxr-xr-x 2 landscape root 4096 May 16 13:53 custom-graph-scripts
-rw-r--r-- 1 root root 12288 May 16 13:53 manager.database
drwxr-xr-x 2 landscape root 4096 May 16 13:53 messages
-rw-r--r-- 1 landscape landscape 23 May 16 13:53 monitor.bpickle
-rw-r--r-- 1 landscape landscape 23 May 16 13:53 monitor.bpickle.old
drwxr-xr-x 5 landscape root 4096 May 16 13:53 package
drwxr-x--- 2 landscape root 4096 May 16 13:53 sockets
-rwxr-xr-x 1 landscape root 100 May 16 13:52 user-update-flag

I'll add that normal functionality should work - registration and regular message exchange.

[astok]

Here is the process I followed to try to reproduce the original issue:

1. Clone my fork of the repo which does not contain the fix in this PR
2. $ cd landscape-client
3. $ dev_lxc create --config ./.dev-lxc/config.yaml jammy
4. Edit landscape-client.conf to remove the data_path and log_dir lines
5. $ dev_lxc shell jammy
6. ubuntu$ sudo pro attach <guid>
7. ubuntu$ sudo apt update && sudo apt install -y landscape-client
8. exit
9. lxc exec landscape-client-jammy -- bash
10. cd /home/ubuntu/landscape-client
11. # umask 027
12. # ./scripts/landscape-config --computer-title test-lndeng-1111-fail --account-name onward --url http://10.112.115.46:8080/message-system --ping-url http://10.112.115.46:8081/ping

I see the message "Registration request sent successfully".

ls -l /var/lib/landscape/ shows:
drwxr-xr-x 7 landscape root 4096 Aug 28 20:16 client
and the contents of the directory are:

drwxr-xr-x 2 landscape landscape  4096 Aug 28 20:15 annotations.d
-rw-r----- 1 root      root        100 Aug 28 20:15 broker.bpickle
drwxr-xr-x 2 landscape root       4096 Aug 28 20:15 custom-graph-scripts
-rw-r--r-- 1 root      root      12288 Aug 28 20:16 manager.database
drwxr-xr-x 2 landscape root       4096 Aug 28 20:15 messages
-rw-r--r-- 1 landscape landscape    23 Aug 28 20:16 monitor.bpickle
-rw-r--r-- 1 landscape landscape    23 Aug 28 20:16 monitor.bpickle.old
drwxr-xr-x 5 landscape root       4096 Aug 28 20:15 package
drwxr-x--- 2 landscape root       4096 Aug 28 20:16 sockets
-rwxr-xr-x 1 landscape root        100 Aug 28 20:06 user-update-flag

Running # journalctl shows me the errors:
Aug 28 20:16:00 landscape-client-jammy landscape-client[5181]: PermissionError: [Errno 13] Permission denied: '/var/lib/landscape/client/broker.bpickle' and ultimately...
Aug 28 20:16:02 landscape-client-jammy systemd[1]: landscape-client.service: Deactivated successfully.

I believe this gives me a tight repro of the original problem.

[astok]

With the PR applied, the contents of the /var/lib/landscape/client directory are:

drwxr-xr-x 2 landscape landscape  4096 Aug 29 13:00 annotations.d
-rw-r--r-- 1 landscape landscape   121 Aug 29 13:00 broker.bpickle
-rw-r----- 1 landscape landscape   100 Aug 29 13:00 broker.bpickle.old
drwxr-xr-x 2 landscape root       4096 Aug 29 13:00 custom-graph-scripts
-rw-r--r-- 1 root      root      12288 Aug 29 13:00 manager.database
drwxr-xr-x 2 landscape root       4096 Aug 29 13:00 messages
-rw-r--r-- 1 landscape landscape   725 Aug 29 13:01 monitor.bpickle
-rw-r--r-- 1 landscape landscape    23 Aug 29 13:00 monitor.bpickle.old
drwxr-xr-x 5 landscape root       4096 Aug 29 13:00 package
drwxr-x--- 2 landscape root       4096 Aug 29 13:00 sockets
-rwxr-xr-x 1 landscape root        100 Aug 29 12:57 user-update-flag

which is correct.

Running # journalctl shows Broker started with config /etc/landscape/client.conf with none of the permissions errors seen previously.

[astok]

LGTM.