配置Linux使用LDAP用户认证的方法

mkdir /root/back
tar -Jcvf /root/back/yum.repos.d-`date '+(%Y.%m.%d_%H:%M:%S)'`.tar.xz /etc/yum.repos.d/
rm -rf /etc/yum.repos.d/*
curl -o /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
curl -o /etc/yum,repos.d/CentOS-epel.repo http://mirrors.aliyun.com/repo/epel-7.repo
yum makecache

yum -y install vim bash-completion openldap-servers openldap-clients nss-pam-ldapd sssd

# 首先备份文件，以免无法复原
mkdir /root/back
tar -Jcvf /root/back/slapd.config-`date '+(%Y.%m.%d_%H:%M:%S)'`.tar.xz /etc/openldap/slapd.d/
tar -Jcvf /root/back/slapd.data-`date '+(%Y.%m.%d_%H:%M:%S)'`.tar.xz /var/lib/ldap/
# 然后再删除配置文件
rm -rf /etc/openldap/slapd.d/*
rm -rf /var/lib/ldap/*
# 复制配置文件到临时目录
mkdir /root/ldap
cd /root/ldap

# file: /root/ldap/slapd.ldif
dn: cn=config
objectClass: olcGlobal
cn: config
olcArgsFile: /var/run/openldap/slapd.args
olcPidFile: /var/run/openldap/slapd.pid
olcTLSCertificateFile: /etc/openldap/certs/server.crt
olcTLSCertificateKeyFile: /etc/openldap/certs/server.key
olcTLSCACertificateFile: /etc/openldap/cacerts/cacert.pem
dn: cn=schema,cn=config
objectClass: olcSchemaConfig
cn: schema
include: file:///etc/openldap/schema/core.ldif
include: file:///etc/openldap/schema/cosine.ldif
include: file:///etc/openldap/schema/nis.ldif
include: file:///etc/openldap/schema/inetorgperson.ldif
dn: olcDatabase=frontend,cn=config
objectClass: olcDatabaseConfig
objectClass: olcFrontendConfig
olcDatabase: frontend
dn: olcDatabase=config,cn=config
objectClass: olcDatabaseConfig
olcDatabase: config
olcAccess: to * 
 by dn.base="gidNumber=0+uidNumber=0,cn=peercred,cn=external,cn=auth" manage 
 by * none
dn: olcDatabase=monitor,cn=config
objectClass: olcDatabaseConfig
olcDatabase: monitor
olcAccess: to * 
 by dn.base="gidNumber=0+uidNumber=0,cn=peercred,cn=external,cn=auth" read 
 by dn.base="cn=Manager,dc=black,dc=com" read 
 by * none
dn: olcDatabase=hdb,cn=config
objectClass: olcDatabaseConfig
objectClass: olcHdbConfig
olcDatabase: hdb
olcSuffix: dc=black,dc=com
olcRootDN: cn=Manager,dc=black,dc=com
olcRootPW: {SSHA}l1vBI/HOMKLEiQZgcm3Co+hFQI68rH1Q
olcDbDirectory: /var/lib/ldap
olcDbIndex: objectClass eq,pres
olcDbIndex: ou,cn,mail,surname,givenname eq,pres,sub

# 首先是创建CA服务的证书文件
cd /etc/pki/CA
openssl genrsa -out private/cakey.pem 2048
openssl req -new -x509 -key private/cakey.pem -out cacert.pem # 这里的证书创建过程就省略不写了。
# 不过需要注意的是，必须要保证后面服务器证书申请的开头部分必须与证书开头相同，否则无法通过CA签发证书。
touch index.txt
echo "01" > serial
# 然后申请签发服务器证书
cd /etc/openldap/certs/
openssl genrsa -out server.key 2048
openssl ca -in server.csr -out server.crt -days 365
# 复制CA证书到指定位置
mkdir /etc/openldap/cacerts
cp /etc/pki/CA/cacert.pem /etc/openldap/cacerts/

slapadd -F "/etc/openldap/slapd.d/" -b "cn=config" -l slapd.ldif
# 这里还需要注意文件属主还是root的，需要改回为openldap
chown -R ldap:ldap /etc/openldap/slapd.d/*
# 然后再开启服务即可
systemctl start slapd

_#################### 100.00% eta none elapsed none fast!
 Closing DB...

1.初始化数据库

dn: dc=black,dc=com
dc: black
objectClass: top
objectClass: domain

dn: cn=Manager,dc=black,dc=com
objectClass: organizationalRole
cn: Manager
description: LDAP Manager

dn: ou=People,dc=black,dc=com
ou: People
objectClass: top
objectClass: organizationalUnit
objectClass: domainRelatedObject
associatedDomain: black.com

dn: ou=Group,dc=black,dc=com
ou: Group
objectClass: top
objectClass: organizationalUnit
objectClass: domainRelatedObject
associatedDomain: black.com

ldapadd -x -D "cn=Manager,dc=black,dc=com" -w 123456 -f base.ldif # 将基础信息导入数据库。
adding new entry "dc=black,dc=com"
 adding new entry "cn=root,dc=black,dc=com"
 adding new entry "ou=People,dc=black,dc=com"
 adding new entry "ou=Group,dc=black,dc=com"

# file: /etc/nslcd.conf
uid nslcd
gid ldap
uri ldap://127.0.0.1/
base dc=black,dc=com
binddn cn=Manager,dc=black,dc=com
bindpw 123456
ssl no
tls_cacertdir /etc/openldap/cacerts

chmod 600 /etc/nslcd.conf
systemctl start nslcd
systemctl enable nslcd

# file: /etc/nsswitch.conf

passwd: files ldap  # 主要就是 passwd、shadow 和 group 这3行需要后面添加ldap
shadow: files ldap
group: files ldap
hosts: files dns myhostname
bootparams: nisplus [NOTFOUND=return] files
ethers: files
netmasks: files
networks: files
protocols: files
rpc: files
services: files sss
netgroup: nisplus sss
publickey: nisplus
automount: files nisplus sss
aliases: files nisplus

getent passwd | grep black
black​:x:1001:1001:black:/home/black:/bin/bash

cd /etc/pam.d/
 mv system-auth{,.bak}
 ln -s system-auth-ac system-auth

# file: /etc/sssd/sssd.conf
[domain/black.com]
autofs_provider = ldap # 配置 autofs 的提供程序为 ldap
id_provider = ldap  # id 的提供程序为 ldap
auth_provider = ldap # 配置 auth 认证的提供程序为 ldap
chpass_provider = ldap # 更改密码 操作时的对用应用
cache_credentials = True # 开启缓存
ldap_search_base = dc=black,dc=com # ldap 查询的base dn
ldap_uri = ldap://127.0.0.1/ # ldap 的 URL 路径
ldap_id_use_start_tls = True # 开启 ldap 的 tls 加密。
ldap_tls_reqcert = never # 不强制要求 tls 加密(这里可以设置为 hard 强制 TLS 加密，如果 tls 无法使用则可能导致服务失败； 由于ldap 与 sssd在同一台，所以不需要 tls 加密)
ldap_tls_cacertdir = /etc/openldap/cacerts # ldap 服务 tls 加密信任证书(CA根证书)。
[sssd]
services = nss, pam, autofs # 提供的服务
domains = black.com # 设置启用的域
[nss]
homedir_substring = /home
[pam]
[sudo]
[autofs]
[ssh]
[pac]
[ifp]
[secrets]
[session_recording]

chmod 600 /etc/sssd/sssd.conf # 注意权限的配置，否则无法启动。
systemctl start sssd
systmctl enable sssd