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@mazgi
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LDAP Auth for SSSD, SSH, SUDO
# uname -a
Linux base 4.0.5-gentoo #1 SMP Wed Jul 1 02:23:16 JST 2015 x86_64 Intel(R) Xeon(R) CPU E5-2640 0 @ 2.50GHz GenuineIntel GNU/Linux

Packages

# emerge -pvq openldap openssh sssd sudo
[ebuild   R   ] net-nds/openldap-2.4.38-r2  USE="berkdb crypt gnutls ipv6 minimal sasl ssl syslog tcpd -cxx -debug -experimental -icu -iodbc -kerberos -odbc -overlays -perl -samba (-selinux) -slp -smbkrb5passwd" ABI_X86="(64) -32 (-x32)" 
[ebuild   R   ] net-misc/openssh-6.9_p1-r2  USE="hpn pam pie ssl -X -X509 -bindist -debug -kerberos -ldap -ldns -libedit -sctp (-selinux) -skey -ssh1 -static" 
[ebuild   R   ] sys-auth/sssd-1.12.4  USE="manpages nls ssh sudo -acl -augeas -autofs -locator -netlink -nfsv4 -python -samba (-selinux) {-test}" ABI_X86="(64) -32 (-x32)" PYTHON_SINGLE_TARGET="python2_7 -python3_3 -python3_4" PYTHON_TARGETS="python2_7 python3_3 -python3_4" 
[ebuild   R   ] app-admin/sudo-1.8.12  USE="ldap nls pam sendmail -offensive (-selinux) -skey" 

LDAP Client configuration

# grep -vE '^\s*($|#)' /etc/openldap/ldap.conf
BASE dc=example,dc=co,dc=jp
URI ldap://ldap1.example.co.jp ldap://ldap2.example.co.jp
tls_reqcert never
sudoers_base ou=SUDOers,dc=example,dc=co,dc=jp
nss_initgroups backlink
binddn cn=Authenticator,dc=example,dc=co,dc=jp
bindpw P@ssw0rd!
# ls -l /etc/openldap/ldap.conf /etc/ldap.conf.sudo
lrwxrwxrwx 1 root root  18 Jul 19 16:35 /etc/ldap.conf.sudo -> openldap/ldap.conf
-rw-r--r-- 1 root root 250 Jul 19 16:36 /etc/openldap/ldap.conf

SSS Configuration

# grep -vE '^\s*($|#)' /etc/sssd/sssd.conf
[sssd]
config_file_version = 2
services = nss,pam,sudo,ssh
domains = example
debug_level = 1
[nss]
filter_users = root,ldap,named,avahi,haldaemon,dbus,radiusd,news,nscd
[pam]
[sudo]
subdomain_enumerate = true
debug_level = 9
[domain/example]
id_provider = ldap
auth_provider = ldap
sudo_provider = ldap
ldap_search_base = dc=example,dc=co,dc=jp
ldap_sudo_search_base = ou=SUDOers,dc=example,dc=co,dc=jp
ldap_tls_reqcert = never
ldap_uri = ldap://ldap1.example.co.jp
ldap_schema = rfc2307
debug_level = 1
enumerate = true
ldap_default_bind_dn = cn=Authenticator,dc=example,dc=co,dc=jp
ldap_default_authtok = P@ssw0rd!
ldap_group_object_class = posixGroup
ldap_group_search_base = ou=Group,dc=example,dc=co,dc=jp
ldap_group_name = cn
ldap_group_member = memberUid
ldap_id_use_start_tls = false
chpass_provider = ldap
cache_credentials = true

Name Service Switch configuration

# grep -vE '^\s*($|#)' /etc/nsswitch.conf
passwd:      compat sss
shadow:      compat sss
group:       compat sss
hosts:       files dns
networks:    files dns
services:    db files
protocols:   db files
rpc:         db files
ethers:      db files
netmasks:    files
netgroup:    files
bootparams:  files
automount:   files
aliases:     files
sudoers:     files ldap sss

PAM configuration

# grep -vE '^\s*($|#)' /etc/pam.d/system-auth
auth            required        pam_env.so 
auth            sufficient      pam_unix.so try_first_pass likeauth nullok 
auth            sufficient      pam_sss.so use_first_pass
auth            optional        pam_permit.so
account required        pam_unix.so 
account [default=bad success=ok user_unknown=ignore]            pam_sss.so
account optional        pam_permit.so
password        required        pam_cracklib.so difok=2 minlen=8 dcredit=2 ocredit=2 retry=3 
password        sufficient      pam_unix.so try_first_pass use_authtok nullok sha512 shadow 
password        sufficient      pam_sss.so use_authtok
password        optional        pam_permit.so
session         required        pam_limits.so 
session         required        pam_env.so 
session         required        pam_unix.so 
session         optional        pam_mkhomedir.so skel=/etc/skel/ umask=0077
session         optional        pam_sss.so
session         optional        pam_permit.so

OpenSSH configuration

# grep -vE '^\s*($|#)' /etc/ssh/sshd_config
PubkeyAuthentication yes
AuthorizedKeysCommand /usr/bin/sss_ssh_authorizedkeys
AuthorizedKeysCommandUser nobody
PasswordAuthentication no
ChallengeResponseAuthentication no
UsePAM yes
PrintMotd no
PrintLastLog no
UsePrivilegeSeparation sandbox          # Default for new installations.
Subsystem       sftp    /usr/lib64/misc/sftp-server
AcceptEnv LANG LC_*
@saqib-ali
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Any recommendations for a GUI to manager Sudoers rules in LDAP or AD?

@auth-day
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@saqib-ali
Red Hat Identity Management
or free version FreeIPA

@KroniK907
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KroniK907 commented May 4, 2017

FusionDirectory is a great tool for managing an openLDAP system in general. It includes a plugin for managing Sudo.

@hdkiller
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there is a typo:

tls_reqcert naver

@mazgi
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Author

mazgi commented May 21, 2020

tls_reqcert naver

thanks, I've fixed it

@pratikbin
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pratikbin commented Sep 20, 2021

why LDAP client config if we are already configuring sssd ? @mazgi

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