ssh pubkey auth only with libpam

sshd_config.diff

--- /etc/ssh/sshd_config.orig	2021-04-10 05:50:44.673514864 +0000
+++ /etc/ssh/sshd_config	2021-04-10 05:59:56.316912290 +0000
@@ -31,7 +31,7 @@
 # Authentication:
 
 #LoginGraceTime 2m
-#PermitRootLogin prohibit-password
+PermitRootLogin prohibit-password
 #StrictModes yes
 #MaxAuthTries 6
 #MaxSessions 10
@@ -55,12 +55,13 @@
 #IgnoreRhosts yes
 
 # To disable tunneled clear text passwords, change to no here!
-#PasswordAuthentication yes
+PasswordAuthentication no 
 #PermitEmptyPasswords no
+AuthenticationMethods publickey
 
 # Change to yes to enable challenge-response passwords (beware issues with
 # some PAM modules and threads)
-ChallengeResponseAuthentication no
+ChallengeResponseAuthentication yes
 
 # Kerberos options
 #KerberosAuthentication no
@@ -121,4 +122,4 @@
 #	AllowTcpForwarding no
 #	PermitTTY no
 #	ForceCommand cvs server
-PasswordAuthentication yes
+PasswordAuthentication no