/**
* Start a KDC server: - create a KDC instance - create Kerberos principals - save Kerberos
* configuration - save keys to keytab file - no pre-auth is required
*/
private static void startKDC(String realm, Map<String, String> principals, String ktab) {
try {
KDC kdc = KDC.create(realm, HOST, 0, true);
kdc.setOption(KDC.Option.PREAUTH_REQUIRED, Boolean.FALSE);
if (principals != null) {
principals
.entrySet()
.stream()
.forEach(
(entry) -> {
String name = entry.getKey();
String password = entry.getValue();
if (password == null || password.isEmpty()) {
System.out.println(
"KDC: add a principal '" + name + "' with a random password");
kdc.addPrincipalRandKey(name);
} else {
System.out.println(
"KDC: add a principal '" + name + "' with '" + password + "' password");
kdc.addPrincipal(name, password.toCharArray());
}
});
}
KDC.saveConfig(KRB5_CONF_FILENAME, kdc);
if (ktab != null) {
File ktabFile = new File(ktab);
if (ktabFile.exists()) {
System.out.println("KDC: append keys to an exising " + "keytab file " + ktab);
kdc.appendKtab(ktab);
} else {
System.out.println("KDC: create a new keytab file " + ktab);
kdc.writeKtab(ktab);
}
}
System.out.println(
"KDC: started on " + HOST + ":" + kdc.getPort() + " with '" + realm + "' realm");
} catch (Exception e) {
throw new RuntimeException("KDC: unexpected exception", e);
}
}
void go() throws Exception {
OneKDC k = new OneKDC(null);
k.writeJAASConf();
Files.delete(Paths.get(OneKDC.KTAB));
// Starts with no keytab
c = Context.fromJAAS("client");
s = Context.fromJAAS("com.sun.security.jgss.krb5.accept");
// Test 1: read new key 1 from keytab
k.addPrincipal(OneKDC.SERVER, "pass1".toCharArray());
k.writeKtab(OneKDC.KTAB);
connect();
// Test 2: service key cached, find 1 in keytab (now contains 1 and 2)
k.addPrincipal(OneKDC.SERVER, "pass2".toCharArray());
k.appendKtab(OneKDC.KTAB);
connect();
// Test 3: re-login. Now find 2 in keytab
c = Context.fromJAAS("client");
connect();
// Test 4: re-login, KDC use 3 this time.
c = Context.fromJAAS("client");
// Put 3 and 4 into keytab but keep the real key back to 3.
k.addPrincipal(OneKDC.SERVER, "pass3".toCharArray());
k.appendKtab(OneKDC.KTAB);
k.addPrincipal(OneKDC.SERVER, "pass4".toCharArray());
k.appendKtab(OneKDC.KTAB);
k.addPrincipal(OneKDC.SERVER, "pass3".toCharArray());
connect();
// Test 5: invalid keytab file, should ignore
try (FileOutputStream fos = new FileOutputStream(OneKDC.KTAB)) {
fos.write("BADBADBAD".getBytes());
}
connect();
// Test 6: delete keytab file, identical to revoke all
Files.delete(Paths.get(OneKDC.KTAB));
try {
connect();
throw new Exception("Should not success");
} catch (GSSException gsse) {
System.out.println(gsse);
KrbException ke = (KrbException) gsse.getCause();
// KrbApReq.authenticate(*) if (dkey == null)...
// This should have been Krb5.KRB_AP_ERR_NOKEY
if (ke.returnCode() != Krb5.API_INVALID_ARG) {
throw new Exception("Not expected failure code: " + ke.returnCode());
}
}
// Test 7: 3 revoked, should fail (now contains only 5)
k.addPrincipal(OneKDC.SERVER, "pass5".toCharArray());
k.writeKtab(OneKDC.KTAB); // overwrite keytab, which means
// old key is revoked
try {
connect();
throw new Exception("Should not success");
} catch (GSSException gsse) {
System.out.println(gsse);
// Since 7197159, different kvno is accepted, this return code
// will never be thrown out again.
// KrbException ke = (KrbException)gsse.getCause();
// if (ke.returnCode() != Krb5.KRB_AP_ERR_BADKEYVER) {
// throw new Exception("Not expected failure code: " +
// ke.returnCode());
// }
}
// Test 8: an empty KDC means revoke all
KDC.create("EMPTY.REALM").writeKtab(OneKDC.KTAB);
try {
connect();
throw new Exception("Should not success");
} catch (GSSException gsse) {
System.out.println(gsse);
KrbException ke = (KrbException) gsse.getCause();
// KrbApReq.authenticate(*) if (dkey == null)...
// This should have been Krb5.KRB_AP_ERR_NOKEY
if (ke.returnCode() != Krb5.API_INVALID_ARG) {
throw new Exception("Not expected failure code: " + ke.returnCode());
}
}
}
