Jak nainstalovat a nakonfigurovat Kerberos v CentOS/RHEL 7

Konfgurace Kerberos V5

1. Nainstalujte balíčky krb5-libs, krb5-server a krb5-workstation

2. Upravte soubor /etc/krb5.conf a /var/kerberos/krb5kdc/kdc.conf aby odrážely váš název sféry a doménu k mapování sfér. Jednoduchý realm lze sestavit nahrazením instancí EXAMPLE.COM a example.com vaším názvem domény (ujistěte se, že zachováte stejná velká a malá písmena) a změnou kerberos.example.com na plně kvalifikovaný název hostitele serveru.

Například:

# cat /etc/krb5.conf
[logging]                                  
 default = FILE:/var/log/krb5libs.log      
 kdc = FILE:/var/log/krb5kdc.log           
 admin_server = FILE:/var/log/kadmind.log  
                                           
[libdefaults]                              
 ticket_lifetime = 24000                   
 default_realm = UK.ORACLE.COM             
                                           
[realms]                                   
 UK.ORACLE.COM = {                         
  kdc = ukp9174.uk.oracle.com:88           
  admin_server = ukp9174.uk.oracle.com:749 
  default_domain = uk.oracle.com           
 }                                         
                                           
[domain_realm]                             
 .uk.oracle.com = UK.ORACLE.COM            
 uk.oracle.com = UK.ORACLE.COM             
                                           
[kdc]                                      
 profile = /var/kerberos/krb5kdc/kdc.conf  

[pam]
 debug = false
 ticket_lifetime = 36000
 renew_lifetime = 36000
 forwardable = true
 krb4_convert = false

# cat /var/kerberos/krb5kdc/kdc.conf
[kdcdefaults]                                                                   
 kdc_ports = 88                                                                 
 acl_file = /var/kerberos/krb5kdc/kadm5.acl                                     
 dict_file = /usr/dict/words                                                    
 admin_keytab = /var/kerberos/krb5kdc/kadm5.keytab                              
                                                                                
[realms]                                                                        
 UK.ORACLE.COM = {                                                              
  master_key_type = des-cbc-crc                                                 
  database_name = /var/kerberos/krb5kdc/principal                               
  admin_keytab = /var/kerberos/krb5kdc/kadm5.keytab                             
  supported_enctypes = des-cbc-crc:normal des3-cbc-raw:normal des3-cbc-sha1:norm
al des-cbc-crc:v4 des-cbc-crc:afs3                                              
  kadmind_port = 749                                                            
  acl_file = /var/kerberos/krb5kdc/kadm5.acl                                    
  dict_file = /usr/dict/words                                                   
 }

3. Upravte soubor /var/kerberos/krb5kdc/kadm5.acl určit, kteří principálové mají přístup k databázi Kerberos

# vi /var/kerberos/krb5kdc/kadm5.acl
*/admin@UK.ORACLE.COM *

4. Vytvořte databázi kerberos pomocí příkazu kdb5_util:

# kdb5_util create -s 
 
Initializing database '/var/kerberos/krb5kdc/principal' for realm 'UK.ORACLE.COM', 
 master key name 'K/M@UK.ORACLE.COM' 
 You will be prompted for the database Master Password. 
 It is important that you NOT FORGET this password. 
 Enter KDC database master key: admin 
 Re-enter KDC database master key to verify: admin

5. Spusťte služby Kerberos:

# service krb5kdc start 

 Starting Kerberos 5 KDC:                                   [  OK  ] 

# service kadmin start 
  Extracting kadm5 Service Keys 
  Authenticating as principal root/admin@UK.ORACLE.COM with password. 
  Entry for principal kadmin/admin with kvno 3, encryption type DES cbc mode with CRC-32 added to 
  keytab WRFILE:/var/kerberos/krb5kdc/kadm5.keytab. 
  Entry for principal kadmin/admin with kvno 3, encryption type Triple DES cbc mode raw added to 
  keytab WRFILE:/var/kerberos/krb5kdc/kadm5.keytab. 
  Entry for principal kadmin/changepw with kvno 3, encryption type DES cbc mode with CRC-32 added 
  to keytab WRFILE:/var/kerberos/krb5kdc/kadm5.keytab. 
  Entry for principal kadmin/changepw with kvno 3, encryption type Triple DES cbc mode raw added 
  to keytab WRFILE:/var/kerberos/krb5kdc/kadm5.keytab. 
                                                             [  OK  ] 
  Starting Kerberos 5 Admin Server                           [  OK  ] 

# service krb524 start 
  Starting Kerberos 5-to-4 Server:                           [  OK  ] 

6. Přidejte principy Kerberos:

# kadmin.local 
  Authenticating as principal root/admin@UK.ORACLE.COM with password. 
> kadmin.local:  addprinc host/ukp9174.uk.oracle.com 
  WARNING: no policy specified for host/ukp9174.uk.oracle.com@UK.ORACLE.COM; defaulting to no policy 
  Enter password for principal "host/ukp9174.uk.oracle.com@UK.ORACLE.COM":    admin 
  Re-enter password for principal "host/ukp9174.uk.oracle.com@UK.ORACLE.COM":  admin 
  Principal "host/ukp9174.uk.oracle.com@UK.ORACLE.COM" created. 

Všimněte si, že hostitel je slovo „hostitel“, nikoli název hostitele serveru a ukp9174.uk.oracle.com je plně kvalifikovaný název hostitele serveru.

> kadmin.local: addprinc root
WARNING: no policy specified for root@UK.ORACLE.COM; defaulting to no policy 
  Enter password for principal "root@UK.ORACLE.COM":    admin 
  Re-enter password for principal "root@UK.ORACLE.COM":  admin 
  Principal "root@UK.ORACLE.COM" created. 

7. Přidejte hostitele do záložky klíčů:

# kadmin.local:  ktadd -k /etc/krb5.keytab host/ukp9174.uk.oracle.com 
  Entry for principal host/ukp9174.uk.oracle.com with kvno 2, encryption type DES cbc mode with CRC-32 
  added to keytab WRFILE:/etc/krb5.keytab. 
  Entry for principal host/ukp9174.uk.oracle.com with kvno 2, encryption type Triple DES cbc mode raw 
  added to keytab WRFILE:/etc/krb5.keytab. 
>  kadmin.local:  exit

8. Otestujte, zda můžete získat lístek:

# kinit 
Password for root@UK.ORACLE.COM: admin

9. Prokažte, že máte lístek:

# klist
Ticket cache: FILE:/tmp/krb5cc_0
Default principal: root@UK.ORACLE.COM

Valid starting     Expires            Service principal
01/02/01 11:14:15  01/02/01 21:14:15  krbtgt/UK.ORACLE.COM@UK.ORACLE.COM

Kerberos 4 ticket cache: /tmp/tkt0

Jakmile to funguje, máte to správně nastavené.