netmgr should validate dns_domains input character limit (if given more than 256 character , systemd will reject)

[suezzelur]

Two validations to be done.

1. total character limit , (not more 256) . netmgr does not validate the limit and add directly into .network file , but systemd reject this.

   root@appcheck-vm [ /etc/systemd/network ]# netmgr dns_domains --set --domains abcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsd.qe.local
   root@appcheck-vm [ /etc/systemd/network ]# netmgr dns_domains --get
   Error: value not found
   root@appcheck-vm [ /etc/systemd/network ]# cat /etc/systemd/network/00-eth0.network

[Match]
Name=eth0

[Network]
DHCP=yes
Domains=abcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsdabcdefoghijklimsgshsd.qe.local

2. total number of entries , (not more 6) , netmgr does not validates the limit and add directly into .network file , but systemd rejects all remaining .

root@appcheck-vm [ /etc/systemd/network ]# netmgr dns_domains --set --domains netmgmtqe1.local,netmgmtqe2.local,netmgmtqe3.local,netmgmtqe4.local,netmgmtqe5.local,netmgmtqe6.local,netmgmtqe7.local
root@appcheck-vm [ /etc/systemd/network ]# echo $?
0
root@appcheck-vm [ /etc/systemd/network ]# netmgr dns_domains --get
Domains=netmgmtqe1.local netmgmtqe2.local netmgmtqe3.local netmgmtqe4.local netmgmtqe5.local netmgmtqe6.local # Too many search domains configured, remaining ones ignored. # Total length of all search domains is too long, remaining ones ignored.