Changes for page KerberosAndLDAP

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1		-{{toc/}}
2		-
3	3	= Debian =
4	4
5		-The guide I followed was https://wiki.debian.org/LDAP/OpenLDAPSetup#Kerberos which while it worked required some minor tweaks. I obtained edit privileges for the Debian Wiki and updated the guide with the fixes that I found. I however have a Synology NAS and that can run an LDAP Server. So this guide differs from the upstream Debian Guide.
	3	+The guide I followed was [[https:~~/~~/wiki.debian.org/LDAP/OpenLDAPSetup#Kerberos>>https://wiki.debian.org/LDAP/OpenLDAPSetup#Kerberos]] which while it worked required some minor tweaks. I obtained edit privileges for the Debian Wiki and updated the guide with the fixes that I found. I however have a Synology NAS and that can run an LDAP Server. So this guide differs a little from the upstream Debian Guide.
6	6
7		-Assumption is that you have installed the LDAP Server package on your NAS and gone through initial configuration steps, so it has a domain, there is a DN you can bind as and so forth. It is also assumed you have a Debian system (12.5 or later, though this guide should work with 11.x and likely 10.x as well) that will become your KDC and KAdmin server.
8	8
9		-Recommendation is that you create actual ##.ldif## files rather than use here-documents as used in this guide. It is far easier to make adjustments to things if you have a file to edit rather than having to type it all out again or paste it and then have to try and make edits to it without making mistakes.
	6	+First, install the packages containing the LDAP-enabled Kerberos servers ([[krb5-kdc-ldap>>url:https://packages.debian.org/krb5-kdc-ldap]] and [[krb5-admin-server>>url:https://packages.debian.org/krb5-admin-server]]) and the [[schema2ldif>>url:https://packages.debian.org/schema2ldif]] tool:
10	10
11		-**The guide is for illustration. Expectation is that you do not follow it verbatim but adapt it to your needs.**
	8	+##{{{$ sudo apt install krb5-kdc-ldap krb5-admin-server schema2ldif}}}##
12	12
13	13
14		-===== Install packages: =====
	11	+Then load the ##kerberos## schema:
15	15
16		-(% class="wikigeneratedid" %)
17		-The packages you need are [[krb5-kdc-ldap>>url:https://packages.debian.org/krb5-kdc-ldap]], [[krb5-admin-server>>url:https://packages.debian.org/krb5-admin-server]] for the actual KDC and [[schema2ldif>>url:https://packages.debian.org/schema2ldif]]  plus [[slapd>>https://packages.debian.org/search?keywords=slapd]] for adding the schema and ##slappasswd##. They are to be installed on your designated Debian host.
	13	+##{{{$ zcat /usr/share/doc/krb5-kdc-ldap/kerberos.openldap.ldif.gz | ldapadd -H ldap:~/~/nas.fqdn/ -D uid=root,cn=users,dc=example,dc=com}}}##
18	18
19		-(% style="color:#400" %)
20		-##{{{$ sudo apt install krb5-kdc-ldap krb5-admin-server schema2ldif}}}##
	15	+##{{{Password:}}}##
21	21
	17	+##{{{adding new entry "cn=kerberos,cn=schema,cn=config"}}}##
22	22
23		-===== Load ##kerberos LDAP## schema: =====
	19	+##{{{$}}}##
24	24
25		-Now you need to load the kerberos schema into the LDAP server on the Synology. And here you need to use the ##cn=config## DN.
26	26
27		-(% style="color:#400" %)
28		-##{{{$ zcat /usr/share/doc/krb5-kdc-ldap/kerberos.openldap.ldif.gz | ldapadd -H ldaps://nas.example.com/ -D cn=config -W}}}##
29		-##{{{Enter LDAP Password:}}}##
30		-##{{{adding new entry "cn=kerberos,cn=schema,cn=config"}}}##
31		-##{{{$}}}##
	22	+Having an index on the ##krbPrincipalName## improves performance and also suppresses some log messages if ##slapd## is configured to log more than default for the database(s) where you intend to store Kerberos data. As this is OpenLDAP on the Synology, it does not use mdb format, it uses bdb:
32	32
	24	+##{{{$ sudo ldapmodify -H ldap://nas.fqhn <<EOF
	25	+dn: olcDatabase={1}bdb,cn=config
	26	+add: olcDbIndex
	27	+olcDbIndex: krbPrincipalName eq,pres,sub
	28	+EOF
	29	+Password:
33	33
34		-===== Create Index on krbPrincipalName: =====
	31	+modifying entry "olcDatabase={1}bdb,cn=config"
	32	+$
	33	+}}}##
35	35
36		-Having an index on the ##krbPrincipalName## improves performance and also suppresses some log messages if ##slapd## is configured to log more than default for the database(s) where you intend to store Kerberos data. As this is OpenLDAP on the Synology, it does not use ##mdb## format, it uses ##bdb##. If you install ##slapd## on Debian, it uses ##mdb## format. It is different database format, but the principle is the same. Again, as you are modifying config, the DN is ##cn=config##. Interestingly, it is still the main password you set for the Synology LDAP server.
37	37
38		-(% style="color:#400" %)
39		-##{{{$ ldapmodify -H ldaps://nas.example.com/ -D cn=config -W <<EOF}}}##
40		-##{{{dn: olcDatabase={1}bdb,cn=config}}}##
41		-##{{{add: olcDbIndex}}}##
42		-##{{{olcDbIndex: krbPrincipalName eq,pres,sub}}}##
43		-##{{{EOF}}}##
44		-##{{{Enter LDAP Password:}}}##
45		-##{{{modifying entry "olcDatabase={1}bdb,cn=config"}}}##
46		-##{{{$}}}##
47	47
	37	+Next, you need to create and configure two entries which will be used by the Kerberos servers to connect to OpenLDAP. If you are running Kerberos and OpenLDAP on the same system, these steps are optional, but recommended. In order to keep things nicely separated, everything will be created under a separate ##organizationalUnit##. Note that a simple bind (##-x -D##) is used instead of an ##EXTERNAL## bind since write access to the dc=example,dc=com DIT is necessary:
48	48
49		-===== Create principals kadmin and kdc: =====
50	50
51		-Next, you create and configure two entries which will be used by the Kerberos servers to connect to OpenLDAP. As you will not run the Kerberos KDC and Admin Server on the same host as OpenLDAP, these steps are required. In order to keep things nicely separated, everything will be created under a separate ##organizationalUnit##. I diverge from the official Debian guide here as I do not agree with the DN they use. I also had to make changes to the DNs of ##kdc## and ##kadmin## due to ##pwdPolicy## applied by Synology to their LDAP server. The official guide will have you use placeholder passwords and that does not work with the Synology LDAP server. You need to generate them upfront with ##slappasswd -h {SSHA}##.
	40	+{{{# ldapadd -x -D cn=admin,dc=example,dc=com -W <<EOF
	41	+dn: ou=Services,dc=example,dc=com
	42	+objectClass: organizationalUnit
	43	+objectClass: top
	44	+ou: Services
52	52
53		-(% style="color:#400" %)
54		-##{{{$ ldapadd -H ldap://nas.example.com/ -D uid=root,cn=users,dc=example,dc=com -W <<EOF}}}##
55		-##{{{dn: ou=kerberos,dc=example,dc=com}}}##
56		-##{{{objectClass: organizationalUnit}}}##
57		-##{{{objectClass: top}}}##
58		-##{{{ou: kerberos}}}##
	46	+dn: ou=kerberos,ou=Services,dc=example,dc=com
	47	+objectClass: organizationalUnit
	48	+objectClass: top
	49	+ou: kerberos
59	59
60		-(% style="color:#400" %)
61		-##{{{dn: cn=kdc,ou=kerberos,dc=example,dc=com}}}##
62		-##{{{cn: kdc}}}##
63		-##{{{sn: kdc}}}##
64		-##{{{objectClass: person}}}##
65		-##{{{objectClass: pwdPolicy}}}##
66		-##{{{pwdAttribute: userPassword}}}##
67		-##{{{pwdMinLength: 8}}}##
68		-##{{{pwdCheckQuality: 2}}}##
69		-##{{{pwdPolicySubentry: cn=kdc,ou=kerberos,dc=example,dc=com}}}##
70		-##{{{userPassword: {SSHA}<password-hash>}}}##
71		-##{{{description: Kerberos KDC Account}}}##
	51	+dn: uid=kdc,ou=kerberos,ou=Services,dc=example,dc=com
	52	+uid: kdc
	53	+objectClass: account
	54	+objectClass: simpleSecurityObject
	55	+userPassword: {CRYPT}x
	56	+description: Kerberos KDC Account
72	72
73		-(% style="color:#400" %)
74		-##{{{dn: cn=kadmin,ou=kerberos,dc=example,dc=com}}}##
75		-##{{{cn: kadmin}}}##
76		-##{{{sn: kadmin}}}##
77		-##{{{objectClass: person}}}##
78		-##{{{objectClass: pwdPolicy}}}##
79		-##{{{pwdAttribute: userPassword}}}##
80		-##{{{pwdMinLength: 8}}}##
81		-##{{{pwdCheckQuality: 2}}}##
82		-##{{{pwdPolicySubentry: cn=kadmin,ou=kerberos,dc=example,dc=com}}}##
83		-##{{{userPassword: {SSHA}<password-hash>}}}##
84		-##{{{description: Kerberos KDC Account}}}##
85		-##{{{EOF}}}##
86		-##{{{Enter LDAP Password:}}}##
	58	+dn: uid=kadmin,ou=kerberos,ou=Services,dc=example,dc=com
	59	+uid: kadmin
	60	+objectClass: account
	61	+objectClass: simpleSecurityObject
	62	+userPassword: {CRYPT}x
	63	+description: Kerberos Admin Server Account
	64	+EOF
	65	+Enter LDAP Password: SECRET
87	87
88		-(% style="color:#400" %)
89		-##{{{adding new entry "ou=kerberos,dc=example,dc=com"}}}##
	67	+adding new entry "ou=Services,dc=example,dc=com"
90	90
91		-(% style="color:#400" %)
92		-##{{{adding new entry "cn=kdc,ou=kerberos,dc=example,dc=com"}}}##
	69	+adding new entry "ou=kerberos,ou=Services,dc=example,dc=com"
93	93
94		-(% style="color:#400" %)
95		-##{{{adding new entry "cn=kadmin,ou=kerberos,dc=example,dc=com"}}}##
	71	+adding new entry "uid=kdc,ou=kerberos,ou=Services,dc=example,dc=com"
96	96
97		-Synology LDAP server did not like adding users with placeholder passwords, because Synology puts in place password policies. Hence changing this to a ##cn## instead of a ##uid##. It seems to have worked out fine as my KDC is fully functioning.
	73	+adding new entry "uid=kadmin,ou=kerberos,ou=Services,dc=example,dc=com"}}}
98	98
	75	+
	76	+