Purpose:
This how-to is for the users who want to setup an environment with CAS in front and OpenLDAP, GSSAPI, Kerberos as the authorization engine.
Environment:
Server: Fedora Core 6 + CAS 3.1 + Tomcat 5.5.20 + OpenLDAP 2.3.30 + Cyrus SASL 2.1.22 + Kerboeros 1.5-23
Client: Fedora Core 6 + Firefox 2
Windows XP + IE6 SP2
Config DNS:
To make SSL and Kerberos work, I have to config DNS at the very beginning.
1. Edit /etc/named.conf, add langhua zone:
zone "1.168.192.IN-ADDR.ARPA." IN {
type master;
file "192.168.1.db";
};
zone "langhua." IN {
type master;
file "named.langhua";
};
2. Create /var/named/named.langhua
$TTL 1H @ SOA localhost. root.localhost. ( 2 3H 1H 1W 1H ) NS localhost. auth.langhua. IN 1H A 192.168.1.110 _kerberos IN TXT "AUTH.LANGHUA" _kerberos._udp.auth.langhua. IN SRV 0 0 88 auth.langhua. _kerberos-master._udp.auth.langhua. IN SRV 0 0 88 auth.langhua. _kerberos-adm._tcp.auth.langhua. IN SRV 0 0 749 auth.langhua. _kpasswd._udp.auth.langhua. IN SRV 0 0 464 auth.langhua. _ldap._tcp.auth.langhua. IN SRV 0 0 389 auth.langhua. _ldap._tcp.dc._msdcs.auth.langhua. IN SRV 0 0 389 auth.langhua. _kerberos._tcp.dc._msdcs.auth.langhua. IN SRV 0 0 88 auth.langhua.
3. Create /var/name/192.168.1.db
$TTL 1H @ SOA localhost. root.localhost. ( 2 3H 1H 1W 1H ) NS localhost. 110 PTR auth.langhua.
4. nslookup auth.langhua
Server: 192.168.1.110
Address: 192.168.1.110#53
Name: auth.langhua
Address: 192.168.1.110
5. dig -x 192.168.1.110
; <<>> DiG 9.3.4-P1 <<>> -x 192.168.1.110
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 3829
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 2
;; QUESTION SECTION:
;110.1.168.192.in-addr.arpa. IN PTR
;; ANSWER SECTION:
110.1.168.192.in-addr.arpa. 3600 IN PTR auth.langhua.
;; AUTHORITY SECTION:
1.168.192.in-addr.arpa. 3600 IN NS localhost.
;; ADDITIONAL SECTION:
localhost. 86400 IN A 127.0.0.1
localhost. 86400 IN AAAA ::1
;; Query time: 1 msec
;; SERVER: 192.168.1.110#53(192.168.1.110)
;; WHEN: Thu Nov 29 04:53:02 2007
;; MSG SIZE rcvd: 137
Config Kerberos:
1. Config /etc/krb5.conf
[logging]
default = FILE:/var/log/krb5libs.log
kdc = FILE:/var/log/krb5kdc.log
admin_server = FILE:/var/log/kadmind.log
[libdefaults]
default_realm = AUTH.LANGHUA
dns_lookup_realm = false
dns_lookup_kdc = false
ticket_lifetime = 24h
forwardable = true
[realms]
AUTH.LANGHUA = {
kdc = auth.langhua:88
admin_server = auth.langhua:749
default_domain = langhua
}
[domain_realm]
.langhua = AUTH.LANGHUA
[kdc]
profile = /var/kerberos/krb5kdc/kdc.conf
[appdefaults]
pam = {
debug = false
ticket_lifetime = 36000
renew_lifetime = 36000
forwardable = true
krb4_convert = false
}
2. kdb5_util create -s
3. Add users to Kerberos
kadmin.local -q "addprinc krbadm@AUTH.LANGHUA"
kadmin.local -q "addprinc ldapadm@AUTH.LANGHUA"
kadmin.local -q "addprinc host/auth.langhua@AUTH.LANGHUA"
kadmin.local -q "addprinc ldap/auth.langhua@AUTH.LANGHUA"
If you face this error in this step, delete the files under /var/kerberos/krb5kdc/ and redo the above step 2 and 3:
kadmin.local: Cannot find/read stored master key while initializing kadmin.local interface
4. Edit /var/kerberos/krb5kdc/kdc.conf
This file is configed in /etc/krb5.conf.
[kdcdefaults]
acl_file = /var/kerberos/krb5kdc/kadm5.acl
dict_file = /usr/share/dict/words
admin_keytab = /var/kerberos/krb5kdc/kadm5.keytab
v4_mode = nopreauth
[realms]
AUTH.LANGHUA = {
master_key_type = des3-hmac-sha1
supported_enctypes = des3-hmac-sha1:normal des-cbc-crc:normal
}
5. Edit /var/kerberos/krb5kdc/kadm5.acl
This file is configed in /var/kerberos/krb5kdc/kdc.conf.
kadmin/admin@AUTH.LANGHUA * ldap/auth.langhua@AUTH.LANGHUA * krbadm@AUTH.LANGHUA * */*@AUTH.LANGHUA i host/auth.langhua@AUTH.LANGHUA *
6. Config /var/kerberos/krb5kdc/kadm5.keytab
This file is configed in /var/kerberos/krb5kdc/kdc.conf.
kadmin.local -q "ktadd -k /var/kerberos/krb5kdc/kadm5.keytab kadmin/admin"
kadmin.local -q "ktadd -k /var/kerberos/krb5kdc/kadm5.keytab kadmin/changepw"
7. Edit /etc/krb.realms
auth.langhua AUTH.LANGHUA .langhua AUTH.LANGHUA
8. Edit /etc/krb.conf
AUTH.LANGHUA AUTH.LANGHUA auth.langhua:88 AUTH.LANGHUA auth.langhua:749 admin server
9. Start Kerberos
/etc/init.d/kadmin start
/etc/init.d/krb5kdc start
Test Kerberos
1. kadmin.local -q "ktadd -k /etc/krb5.keytab host/auth.langhua"
2. kinit -k host/auth.langhua
If the error "kinit(v5): Password incorrect while getting initial credentials" found, delete /etc/krb5.keytab, and redo step 1 and 2.
3. klist
Ticket cache: FILE:/tmp/krb5cc_0
Default principal: host/auth.langhua@AUTH.LANGHUA
Valid starting Expires Service principal
11/29/07 02:44:44 11/30/07 02:44:44 krbtgt/AUTH.LANGHUA@AUTH.LANGHUA
Kerberos 4 ticket cache: /tmp/tkt0
klist: You have no tickets cached
4. Make sure kvno numbers are the same
4.1 kvno host/auth.langhua
host/auth.langhua@AUTH.LANGHUA: kvno = 5
4.2 klist -k /etc/krb5.keytab
Keytab name: FILE:/etc/krb5.keytab
KVNO Principal
--- -------------------------------------------------------------------------
5 host/auth.langhua@AUTH.LANGHUA
5 host/auth.langhua@AUTH.LANGHUA
If the numbers are not same, redo step 1, 2, 3.
5. Test ktelnetd, krlogind, krshd
5.1 Edit ~/.k5login
host/auth.langhua@AUTH.LANGHUA
5.2 Start xinetd
chkconfig klogin on
chkconfig kshell on
chkconfig eklogin on
chkconfig krb5-telnet on
/etc/init.d/xinetd restart
5.3 krlogin auth.langhua -k AUTH.LANGHUA
This rlogin session is encrypting all data transmissions.
Last login: Thu Nov 29 04:46:08 from auth.langhua
You have new mail.
5.4 telnet -x 192.168.1.110 -k AUTH.LANGHUA
Trying 192.168.1.110...
Connected to auth.langhua (192.168.1.110).
Escape character is '^]'.
Waiting for encryption to be negotiated...
[ Kerberos V5 accepts you as ``host/auth.langhua@AUTH.LANGHUA'' ]
done.
Last login: Thu Nov 29 04:46:23 from auth.langhua
You have new mail.
5.5 rsh 192.168.1.110 -k AUTH.LANGHUA
Last login: Thu Nov 29 04:47:00 from auth.langhua
You have new mail.
Kerberos configuration is OK now.
Config Cyrus SASL GSSAPI
1. Add ldap service
1.1 kadmin.local -q "addprinc -randkey ldap/auth.langhua@AUTH.LANGHUA"
1.2 check /var/kerberos/krb5kdc/kadm5.acl has ldap service configed
1.3 kadmin.local -q "ktadd -k /etc/krb5.keytab ldap/auth.langhua"
2. Add a test user
2.1 kadmin.local -q "addprinc test@AUTH.LANGHUA"
2.2 kadmin.local -q "ktadd -k /etc/krb5.keytab test"
2.3 Edit ~/.k5login
test@AUTH.LANGHUA
3. Verify GSSAPI works on your system
3.1 sasl2-sample-server -s ldap -m GSSAPI
trying 10, 1, 6
trying 2, 1, 6
bind: Address already in use
3.2 sasl2-sample-client -s ldap -m GSSAPI auth.langhua
receiving capability list... recv:
GSSAPI
GSSAPI
please enter an authorization id: test
send:
GSSAPI
send:
Y
send:
`[82][2][9][6][9]*[86]H[86][F7][12][1][2][2][1][0]n[82][1][F8]0[82][1][F4][A0][3][2][1][5][A1][3][2][1][E][A2][7][3][5][0] [0][0][0][A3][82][1][10]a[82][1][C]0[82][1][8][A0][3][2][1][5][A1][E][1B][C]AUTH.LANGHUA[A2][1F]0[1D][A0][3][2][1][3][A1][16]0[14][1B][4]ldap[1B][C]auth.langhua[A3][81][CF]0[81][CC][A0][3][2][1][10][A1][3][2][1][4][A2][81][BF][4][81][BC].[A3],FO[CC][12]P
[97]V[A9]g[B5][F6][D0][C4][C9],![DF][F8][8E][A3][16][7][E5])N[E6][11] [8]+[85][FD][1B][11][C3][96][98][80]}g<[A3]5[1E][BC]si[8A]c9[8A][1A]w[13][1E][18][87]([98][E5][E7][89][85]W[AC]s[A5]v[D6]5v[80][A3][FA][A4][81][CA]0[81][C7][A0][3][2][1][10][A2][81][BF][4][81][BC][15]>[D6][CB]h[1B][9]Y[AC][C8]hh[F1][D4][82]GD[FD]4[AA]"$[EC][7F]&[B8][F]D[7][97][82][D][A7][D][A2]9[8C][88][C0]-[DC][E6][A][EB]D6[1F][A4][E2][EE][D1][6]x[15][D1][EE]4d[86][84][99][16][AC][F5]C[E8][A9]u#[CE][C5][E1][9B][E8][B4][93]z[E9])[15][D]L/E[BD][E6]`[1F][F2][BC][1A][D7]1[BF][C1][2]O[8C][1D][A0][C][AB][8B][AB][F5][DB][D4][B1][ED][A][AF][9][B]s[E9][10][FB]u[11][E]N[1F][15][AE]h[F5][1C][8E][92][AA]6|0[F4][FE][CB][9A][9D]c^o4[CB][8C][B8][99][89][A5][18][EA]pE[B1][C7][E8][90][82][EE][A6]([1A]1Q[D0][81]X[C6]q[9B][EA]v[C][FA][E9]jd[84][BD][CF][90]S[8E]P
recv:
`[81][96][6][9][86]H[86][F7][12][1][2][2][2][0]o[81][86]0[81][83][A0][3][2][1][5][A1][3][2][1][F][A2]w0u[A0][3][2][1][10][A2]n[4]l[5],[B7][F6][CD][C][BF][1]{[E0][1F][92][FC][10][94]U[DF][9E][BA]k_[A4]G&[EC]g:[BA]J[C6][C1]sQ:'[87]/[95][C8]W[C5]^47N[9B]im`[BB][B4][C5][EB][BC]w[80][A7][1D]Q[89][8B]L[8D]N[E7][87][C2][EB][D9]k
[95][F1][5][C2]s[16][1][0][0][0]test[8][8][8][8][8][8][8][8]
successful authentication
closing connection
GSSAPI is OK now.
If the server and client can communicate but cannot authen successfully, perhaps it's caused by the driver of your ethernet card.
Config OpenLDAP GSSAPI
1. ldapsearch -Y GSSAPI -b 'o=langhua,c=cn' '(ou=worldwide)'
SASL/GSSAPI authentication started
SASL username: test@AUTH.LANGHUA
SASL SSF: 56
SASL installing layers
# extended LDIF
#
# LDAPv3
# base <o=langhua,c=cn> with scope subtree
# filter: (ou=worldwide)
# requesting: ALL
#
# worldwide, langhua, cn
dn: ou=worldwide,o=langhua,c=cn
objectClass: organizationalUnit
objectClass: top
ou: worldwide
# martin.peschke, worldwide, langhua, cn
dn: uid=martin.peschke,ou=worldwide,o=langhua,c=cn
uid: martin.peschke
ou: worldwide
objectClass: organizationalPerson
objectClass: uidObject
objectClass: person
objectClass: top
sn: Martin Peschke
cn: Martin Peschke
# search result
search: 4
result: 0 Success
# numResponses: 3
# numEntries: 2
2. Edit /etc/slapd.conf
#
# See slapd.conf(5) for details on configuration options.
# This file should NOT be world readable.
#
include /etc/openldap/schema/core.schema
include /etc/openldap/schema/cosine.schema
include /etc/openldap/schema/inetorgperson.schema
include /etc/openldap/schema/nis.schema
include /etc/openldap/schema/krb5-kdc.schema
# Allow LDAPv2 client connections. This is NOT the default.
allow bind_v2
# Do not enable referrals until AFTER you have a working directory
# service AND an understanding of referrals.
#referral ldap://root.openldap.org
pidfile /var/run/openldap/slapd.pid
argsfile /var/run/openldap/slapd.args
# Load dynamic backend modules:
# modulepath /usr/lib/openldap
# moduleload back_bdb.la
# moduleload back_ldap.la
# moduleload back_ldbm.la
# moduleload back_passwd.la
# moduleload back_shell.la
# The next three lines allow use of TLS for encrypting connections using a
# dummy test certificate which you can generate by changing to
# /etc/pki/tls/certs, running "make slapd.pem", and fixing permissions on
# slapd.pem so that the ldap user or group can read it. Your client software
# may balk at self-signed certificates, however.
# TLSCACertificateFile /etc/pki/tls/certs/ca-bundle.crt
# TLSCertificateFile /etc/openldap/slapd.pem
# TLSCertificateKeyFile /etc/pki/tls/certs/slapd.pem
TLSCACertificateFile /etc/pki/demoCA/cacert.pem
TLSCertificateFile /etc/pki/demoCA/certs/ldap-cert.pem
TLSCertificateKeyFile /etc/pki/demoCA/certs/ldap-key.pem
# TLSVerifyClient demand
# Sample security restrictions
# Require integrity protection (prevent hijacking)
# Require 112-bit (3DES or better) encryption for updates
# Require 63-bit encryption for simple bind
# security ssf=1 update_ssf=112 simple_bind=64
# disallow bind_simple
# Sample access control policy:
# Root DSE: allow anyone to read it
# Subschema (sub)entry DSE: allow anyone to read it
# Other DSEs:
# Allow self write access
# Allow authenticated users read access
# Allow anonymous users to authenticate
# Directives needed to implement policy:
# access to dn.base="" by * read
# access to dn.base="cn=Subschema" by * read
#
# if no access controls are present, the default policy
# allows anyone and everyone to read anything but restricts
# updates to rootdn. (e.g., "access to * by * read")
#
# rootdn can always read and write EVERYTHING!
# access to * by * read
#######################################################################
# ldbm and/or bdb database definitions
#######################################################################
database bdb
suffix "o=langhua,c=cn"
# rootdn "uid=root,o=langhua,c=cn"
# Cleartext passwords, especially for the rootdn, should
# be avoided. See slappasswd(8) and slapd.conf(5) for details.
# Use of strong authentication encouraged.
# rootpw {SSHA}mpfjTVX6cJ+oMgoB1wIjJ8HTR/2kyBga
# The database directory MUST exist prior to running slapd AND
# should only be accessible by the slapd and slap tools.
# Mode 700 recommended.
directory /var/lib/ldap
# Indices to maintain for this database
index objectClass eq,pres
index ou,cn,mail,surname,givenname eq,pres,sub
index uidNumber,gidNumber,loginShell eq,pres
index uid,memberUid eq,pres,sub
index nisMapName,nisMapEntry eq,pres,sub
# Replicas of this database
# replogfile /var/lib/ldap/openldap-master-replog
# replica host=ldap-1.example.com:389 starttls=critical
# bindmethod=sasl saslmech=GSSAPI
# authcId=host/ldap-master.example.com@EXAMPLE.COM
# authzTo: uid=[^,]*,o=langhua,c=cn
sasl-realm AUTH.LANGHUA
sasl-host auth.langhua
access to attrs=userPassword
by self write
by dn="uid=test,cn=auth.langhua,cn=gssapi,cn=auth" write
by anonymous auth
by * none
access to *
by dn="uid=test,cn=auth.langhua,cn=gssapi,cn=auth" write
by self write
by * read