【】Linux OpenLDAP集成sssd同步用户并集成SSH登录
前言
sssd服务是一个守护进程，该进程可以用来访问多种验证服务器，如LDAP，Kerberos等，并提供授权。SSSD是 介于本地用户和数据存储之间的进程，本地客户端首先连接SSSD，再由SSSD联系外部资源提供者(一台远程服务器)
(1)避免了本地每个客户端程序对认证服务器大量连接，所有本地程序仅联系SSSD，由SSSD连接认证服务器或SSSD缓存，有效的降低了负载。
(2)允许离线授权。SSSD可以缓存远程服务器的用户认证身份，这允许在远程认证服务器宕机是，继续成功授权用户访问必要的资源。
集成sssd
所有节点安装相关服务
yum -y install openldap-clients sssd authconfig nss-pam-ldapd
将OpenLDAP服务器的/etc/openldap/certs目录下的ldap.key和ldap.crt文件拷贝至OpenLDAP所有客户端节点/etc/openldap/cacerts目录下
[root@cdh1 ~]# scp ldap.key cdh2.macro.com:/etc/openldap/cacerts/
[root@cdh1 ~]# scp ldap.crt cdh3.macro.com:/etc/openldap/cacerts/
在所有客户端节点上执行如下命令
[root@cdh2 cacerts]# cacertdir_rehash /etc/openldap/cacerts/
3.所有节点执行如下命令启用sssd服务（在如下参数中–enableldaptls 如果OpenLDAP服务未启用TLS则将此参数修改为–disableldaptls）
[root@cdh2 cacerts]# authconfig --enablesssd --enablesssdauth --enablerfc2307bis --enableldap --enableldapauth --enableldaptls --disableforcelegacy --disablekrb5 --ldapserver ldap://cdh1.macro.com --ldapbasedn "dc=macro,dc=com" --enablemkhomedir --update
4.修改/etc/sssd/sssd.conf文件，在执行authconfig命令时会默认生成，如果文件不存在则新建，文件内容如下:
[root@cdh2 cacerts]# vim /etc/sssd/sssd.conf
[root@cdh1 home]# cat /etc/sssd/sssd.conf
[domain/default]
autofs_provider = ldap
ldap_schema = rfc2307bis
krb5_realm = MACRO.COM
ldap_search_base = dc=macro,dc=com
krb5_server = cdh1.macro.com
id_provider = ldap
auth_provider = ldap
chpass_provider = ldap
ldap_uri = ldap://cdh1.macro.com
ldap_id_use_start_tls = True
ldap_tls_reqcert = allow
cache_credentials = True
ldap_tls_cacertdir = /etc/openldap/cacerts
[sssd]
services = nss, pam, autofs
config_file_version = 2
domains = default
[nss]
homedir_substring = /home
[pam]
[sudo]
[autofs]
[ssh]
[pac]
[ifp]
修改sssd.conf文件权限
[root@cdh2 sssd]# chmod 600 /etc/sssd/sssd.conf
5.启动sssd服务并加入系统自启动
[root@cdh2 sssd]# systemctl start sssd
[root@cdh2 sssd]# systemctl enable sssd
[root@cdh2 sssd]# systemctl status sssd
6.至此完成sssd的配置，可以通过id查看用户OpenLDAP的用户
[user_w@cdh1 root]$ more /etc/passwd |grep etl_user
[user_w@cdh1 root]$ id etl_user
uid=50001(etl_user) gid=50001(etl_user) groups=50001(etl_user)
OpenLDAP与SSH集成
1.修改配置文件/etc/ssh/sshd_config，使ssh通过pam认证账户
#PasswordAuthentication yes
#PermitEmptyPasswords no
PasswordAuthentication yes
# and ChallengeResponseAuthentication to 'no'.
# WARNING: 'UsePAM no' is not supported in Red Hat Enterprise Linux and may cause several
# problems.
UsePAM yes
2.修改配置文件/etc/pam.d/sshd，以确认调用pam认证文件
# pam_selinux.so open should only be followed by sessions to be executed in the user context
session required pam_selinux.so open env_params
session required pam_namespace.so
session optional pam_keyinit.so force revoke
session include password-auth
session include postlogin
session required pam_mkhomedir.so
# Used with polkit to reauthorize users in remote sessions
-session optional pam_reauthorize.so prepare
3.修改配置文件
[root@cdh2 sssd]# vim /etc/pam.d/password-auth
#%PAM-1.0
# This file is auto-generated.
# User changes will be destroyed the next time authconfig is run.
auth required pam_env.so
auth [default=1 success=ok] pam_localuser.so
auth [success=done ignore=ignore default=die] pam_unix.so nullok try_first_pass
auth requisite pam_succeed_if.so uid >= 1000 quiet_success
auth sufficient pam_sss.so forward_pass
#auth sufficient pam_ldap.so forward_pass
auth required pam_deny.so
account required pam_unix.so broken_shadow
account sufficient pam_localuser.so
account sufficient pam_succeed_if.so uid < 1000 quiet
account [default=bad success=ok user_unknown=ignore] pam_sss.so
#account [default=bad success=ok user_unknown=ignore] pam_ldap.so
account required pam_permit.so
password requisite pam_pwquality.so try_first_pass local_users_only retry=3 authtok_type=
password sufficient pam_unix.so sha512 shadow nullok try_first_pass use_authtok
password sufficient pam_sss.so use_authtok
#password sufficient pam_ldap.so use_authtok
password required pam_deny.so
session optional pam_keyinit.so revoke
session required pam_limits.so
-session optional pam_systemd.so
session optional pam_mkhomedir.so umask=0077
session [success=1 default=ignore] pam_succeed_if.so service in crond quiet use_uid
session required pam_unix.so
session optional pam_sss.so
#session optional pam_ldap.so
4.修改/etc/pam.d/system-auth配置文件
[root@cdh1 ~]# cat /etc/pam.d/system-auth
#%PAM-1.0
# This file is auto-generated.
# User changes will be destroyed the next time authconfig is run.
auth required pam_env.so
auth [default=1 success=ok] pam_localuser.so
auth [success=done ignore=ignore default=die] pam_unix.so nullok try_first_pass
auth requisite pam_succeed_if.so uid >= 1000 quiet_success
auth sufficient pam_sss.so forward_pass
#auth sufficient pam_ldap.so forward_pass
auth required pam_deny.so
account required pam_unix.so broken_shadow
account sufficient pam_localuser.so
account sufficient pam_succeed_if.so uid < 1000 quiet
account [default=bad success=ok user_unknown=ignore] pam_sss.so
#account [default=bad success=ok user_unknown=ignore] pam_ldap.so
account required pam_permit.so
password requisite pam_pwquality.so try_first_pass local_users_only retry=3 authtok_type=
password sufficient pam_unix.so sha512 shadow nullok try_first_pass use_authtok
password sufficient pam_sss.so use_authtok
#password sufficient pam_ldap.so use_authtok
password required pam_deny.so
session optional pam_keyinit.so revoke
session required pam_limits.so
-session optional pam_systemd.so
session optional pam_mkhomedir.so umask=0077
session [success=1 default=ignore] pam_succeed_if.so service in crond quiet use_uid
session required pam_unix.so
#session optional pam_sss.so
session optional pam_ldap.so
5.重启sshd服务
systemctl restart sshd
至此就完成了OpenLDAP与SSH的集成。
验证SSH登录
1.确认etl_user用户只存在于OpenLDAP
[root@cdh1 ~]# more /etc/passwd |grep etl_user
[root@cdh1 ~]# id etl_user
uid=50001(etl_user) gid=50001(etl_user) groups=50001(etl_user)
2.su切换到etl_user用户
[root@cdh1 ~]# su etl_user
[etl_user@cdh1 root]$ cd ~
[etl_user@cdh1 ~]$ pwd
/home/etl_user
[etl_user@cdh1 ~]$ id
uid=50001(etl_user) gid=50001(etl_user) groups=50001(etl_user)
3.ssh登录本机
[root@cdh1 ~]# ssh etl_user@localhost
etl_user@localhost's password:
Last login: Thu Oct 1 22:20:08 2020
[etl_user@cdh1 ~]$ pwd
/home/etl_user
[etl_user@cdh1 ~]$ id
uid=50001(etl_user) gid=50001(etl_user) groups=50001(etl_user)
4.ssh远程登录
[root@cdh1 ~]# ssh etl_user@cdh2.macro.com
etl_user@cdh2.macro.com's password:
Last login: Thu Oct 1 21:41:19 2020 from 192.168.0.171
[etl_user@cdh2 ~]$ pwd
/home/etl_user
[etl_user@cdh2 ~]$ id
uid=50001(etl_user) gid=50001(etl_user) groups=50001(etl_user)
转载连接：https://cloud.tencent.com/developer/article/1719640?from=15425
