[src/trunk]: src/etc/pam.d pam: Disable pam_krb5, pam_ksu by default.

[riastradh <riastradh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/4fbc97727f37
branches:  trunk
changeset: 376495:4fbc97727f37
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Tue Jun 20 22:00:00 2023 +0000

description:
pam: Disable pam_krb5, pam_ksu by default.

These are not useful unless you also set up /etc/krb5.conf and a
keytab for the host from the Kerberos KDC.  But having them enabled
by default means that creating /etc/krb5.conf just to enable use of
Kerberos for _client-side_ single sign-on creates usability issues.

As proposed on tech-security:
https://mail-index.netbsd.org/tech-security/2023/06/16/msg001160.html

diffstat:

 etc/pam.d/display_manager |  6 +++---
 etc/pam.d/ftpd            |  6 +++---
 etc/pam.d/sshd            |  8 ++++----
 etc/pam.d/su              |  4 ++--
 etc/pam.d/system          |  8 ++++----
 5 files changed, 16 insertions(+), 16 deletions(-)

diffs (132 lines):

diff -r a7c715f50577 -r 4fbc97727f37 etc/pam.d/display_manager
--- a/etc/pam.d/display_manager Tue Jun 20 17:23:01 2023 +0000
+++ b/etc/pam.d/display_manager Tue Jun 20 22:00:00 2023 +0000
@@ -1,4 +1,4 @@
-# $NetBSD: display_manager,v 1.5 2010/11/13 19:19:40 christos Exp $
+# $NetBSD: display_manager,v 1.6 2023/06/20 22:00:00 riastradh Exp $
 #
 # PAM configuration for the display manager services.  Specific display
 # manager service configurations can include this one.
@@ -7,14 +7,14 @@
 # auth
 auth           required        pam_nologin.so          no_warn
 auth           sufficient      pam_skey.so             no_warn try_first_pass
-auth           sufficient      pam_krb5.so             no_warn try_first_pass
+#auth          sufficient      pam_krb5.so             no_warn try_first_pass
 auth           optional        pam_afslog.so           no_warn try_first_pass
 # pam_ssh has potential security risks.  See pam_ssh(8).
 #auth          sufficient      pam_ssh.so              no_warn try_first_pass
 auth           required        pam_unix.so             no_warn try_first_pass
 
 # account
-account        required        pam_krb5.so
+#account       required        pam_krb5.so
 account                required        pam_unix.so
 
 # session
diff -r a7c715f50577 -r 4fbc97727f37 etc/pam.d/ftpd
--- a/etc/pam.d/ftpd    Tue Jun 20 17:23:01 2023 +0000
+++ b/etc/pam.d/ftpd    Tue Jun 20 22:00:00 2023 +0000
@@ -1,4 +1,4 @@
-# $NetBSD: ftpd,v 1.7 2008/03/26 11:31:17 lukem Exp $
+# $NetBSD: ftpd,v 1.8 2023/06/20 22:00:00 riastradh Exp $
 #
 # PAM configuration for the "ftpd" service
 #
@@ -8,14 +8,14 @@
 # pam_unix.
 auth           required        pam_nologin.so          no_warn
 auth           sufficient      pam_skey.so             no_warn try_first_pass
-auth           sufficient      pam_krb5.so             no_warn try_first_pass
+#auth          sufficient      pam_krb5.so             no_warn try_first_pass
 auth           optional        pam_afslog.so           no_warn try_first_pass
 auth           required        pam_unix.so             no_warn try_first_pass
 
 # account
 # Even though this is identical to "system", we open code it here because
 # we open code the auth stack.
-account                required        pam_krb5.so
+#account       required        pam_krb5.so
 account                required        pam_unix.so
 
 # session
diff -r a7c715f50577 -r 4fbc97727f37 etc/pam.d/sshd
--- a/etc/pam.d/sshd    Tue Jun 20 17:23:01 2023 +0000
+++ b/etc/pam.d/sshd    Tue Jun 20 22:00:00 2023 +0000
@@ -1,4 +1,4 @@
-# $NetBSD: sshd,v 1.9 2008/03/26 11:31:17 lukem Exp $
+# $NetBSD: sshd,v 1.10 2023/06/20 22:00:00 riastradh Exp $
 #
 # PAM configuration for the "sshd" service
 #
@@ -6,14 +6,14 @@
 # auth
 auth           required        pam_nologin.so  no_warn
 auth           sufficient      pam_skey.so     no_warn try_first_pass
-auth           sufficient      pam_krb5.so     no_warn try_first_pass
+#auth          sufficient      pam_krb5.so     no_warn try_first_pass
 auth           optional        pam_afslog.so   no_warn try_first_pass
 # pam_ssh has potential security risks.  See pam_ssh(8).
 #auth          sufficient      pam_ssh.so      no_warn try_first_pass
 auth           required        pam_unix.so     no_warn try_first_pass
 
 # account
-account                required        pam_krb5.so
+#account       required        pam_krb5.so
 account                required        pam_login_access.so
 account                required        pam_unix.so
 
@@ -23,5 +23,5 @@ account               required        pam_unix.so
 session                required        pam_permit.so
 
 # password
-password       sufficient      pam_krb5.so     no_warn try_first_pass
+#password      sufficient      pam_krb5.so     no_warn try_first_pass
 password       required        pam_unix.so     no_warn try_first_pass
diff -r a7c715f50577 -r 4fbc97727f37 etc/pam.d/su
--- a/etc/pam.d/su      Tue Jun 20 17:23:01 2023 +0000
+++ b/etc/pam.d/su      Tue Jun 20 22:00:00 2023 +0000
@@ -1,4 +1,4 @@
-# $NetBSD: su,v 1.8 2020/03/03 00:47:33 christos Exp $
+# $NetBSD: su,v 1.9 2023/06/20 22:00:00 riastradh Exp $
 #
 # PAM configuration for the "su" service
 #
@@ -8,7 +8,7 @@ auth            sufficient      pam_rootok.so           no_warn
 auth           sufficient      pam_self.so             no_warn
 auth           sufficient      pam_skey.so             no_warn try_first_pass
 #auth          sufficient      pam_u2f.so              authfile=/etc/u2f_mappings cue
-auth           sufficient      pam_ksu.so              no_warn try_first_pass
+#auth          sufficient      pam_ksu.so              no_warn try_first_pass
 #auth          sufficient      pam_group.so            no_warn group=rootauth root_only authenticate
 auth           requisite       pam_group.so            no_warn group=wheel root_only fail_safe
 auth           required        pam_unix.so             no_warn try_first_pass nullok
diff -r a7c715f50577 -r 4fbc97727f37 etc/pam.d/system
--- a/etc/pam.d/system  Tue Jun 20 17:23:01 2023 +0000
+++ b/etc/pam.d/system  Tue Jun 20 22:00:00 2023 +0000
@@ -1,21 +1,21 @@
-# $NetBSD: system,v 1.8 2008/03/26 11:31:17 lukem Exp $
+# $NetBSD: system,v 1.9 2023/06/20 22:00:00 riastradh Exp $
 #
 # System-wide defaults
 #
 
 # auth
 auth           sufficient      pam_skey.so             no_warn try_first_pass
-auth           sufficient      pam_krb5.so             no_warn try_first_pass
+#auth          sufficient      pam_krb5.so             no_warn try_first_pass
 auth           optional        pam_afslog.so           no_warn try_first_pass
 auth           required        pam_unix.so             no_warn try_first_pass nullok
 
 # account
-account        required        pam_krb5.so
+#account       required        pam_krb5.so
 account                required        pam_unix.so
 
 # session
 session                required        pam_lastlog.so          no_fail no_nested
 
 # password
-password       sufficient      pam_krb5.so             no_warn try_first_pass
+#password      sufficient      pam_krb5.so             no_warn try_first_pass
 password       required        pam_unix.so             no_warn try_first_pass