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/*-
* Copyright (c) 1990, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "bsd_locl.h"
RCSID("$Id: klogin.c,v 1.27 1999/10/04 16:11:48 bg Exp $");
#ifdef KERBEROS
#define VERIFY_SERVICE "rcmd"
extern int notickets;
extern char *krbtkfile_env;
static char tkt_location[MaxPathLen];
static int
multiple_get_tkt(char *name,
char *instance,
char *realm,
char *service,
char *sinstance,
int life,
char *password)
{
int ret;
int n;
char rlm[256];
/* First try to verify against the supplied realm. */
ret = krb_get_pw_in_tkt(name, instance, realm, service, realm, life,
password);
if(ret == KSUCCESS)
return KSUCCESS;
/* Verify all local realms, except the supplied realm. */
for (n = 1; krb_get_lrealm(rlm, n) == KSUCCESS; n++)
if (strcmp(rlm, realm) != 0) {
ret = krb_get_pw_in_tkt(name, instance, rlm,service, rlm,life, password);
if (ret == KSUCCESS)
return KSUCCESS;
}
return ret;
}
/*
* Attempt to log the user in using Kerberos authentication
*
* return 0 on success (will be logged in)
* 1 if Kerberos failed (try local password in login)
*/
int
klogin(struct passwd *pw, char *instance, char *localhost, char *password)
{
int kerror;
AUTH_DAT authdata;
KTEXT_ST ticket;
struct hostent *hp;
u_int32_t faddr;
char realm[REALM_SZ], savehost[MaxHostNameLen];
extern int noticketsdontcomplain;
#ifdef KLOGIN_PARANOID
noticketsdontcomplain = 0; /* enable warning message */
#endif
/*
* Root logins don't use Kerberos.
* If we have a realm, try getting a ticket-granting ticket
* and using it to authenticate. Otherwise, return
* failure so that we can try the normal passwd file
* for a password. If that's ok, log the user in
* without issuing any tickets.
*/
if (strcmp(pw->pw_name, "root") == 0 ||
krb_get_lrealm(realm, 1) != KSUCCESS)
return (1);
noticketsdontcomplain = 0; /* enable warning message */
/*
* get TGT for local realm
* tickets are stored in a file named TKT_ROOT plus uid
* except for user.root tickets.
*/
if (strcmp(instance, "root") != 0)
snprintf(tkt_location, sizeof(tkt_location),
"%s%u_%u",
TKT_ROOT, (unsigned)pw->pw_uid, (unsigned)getpid());
else {
snprintf(tkt_location, sizeof(tkt_location),
"%s_root_%d", TKT_ROOT,
(unsigned)pw->pw_uid);
}
krbtkfile_env = tkt_location;
krb_set_tkt_string(tkt_location);
/*
* Set real as well as effective ID to 0 for the moment,
* to make the kerberos library do the right thing.
*/
if (setuid(0) < 0) {
warnx("setuid");
return (1);
}
/*
* Get ticket
*/
kerror = multiple_get_tkt(pw->pw_name,
instance,
realm,
KRB_TICKET_GRANTING_TICKET,
realm,
DEFAULT_TKT_LIFE,
password);
/*
* If we got a TGT, get a local "rcmd" ticket and check it so as to
* ensure that we are not talking to a bogus Kerberos server.
*
* There are 2 cases where we still allow a login:
* 1: the VERIFY_SERVICE doesn't exist in the KDC
* 2: local host has no srvtab, as (hopefully) indicated by a
* return value of RD_AP_UNDEC from krb_rd_req().
*/
if (kerror != INTK_OK) {
if (kerror != INTK_BADPW && kerror != KDC_PR_UNKNOWN) {
syslog(LOG_ERR, "Kerberos intkt error: %s",
krb_get_err_text(kerror));
dest_tkt();
}
return (1);
}
if (chown(TKT_FILE, pw->pw_uid, pw->pw_gid) < 0)
syslog(LOG_ERR, "chown tkfile (%s): %m", TKT_FILE);
strlcpy(savehost, krb_get_phost(localhost), sizeof(savehost));
#ifdef KLOGIN_PARANOID
/*
* if the "VERIFY_SERVICE" doesn't exist in the KDC for this host,
* don't allow kerberos login, also log the error condition.
*/
kerror = krb_mk_req(&ticket, VERIFY_SERVICE, savehost, realm, 33);
if (kerror == KDC_PR_UNKNOWN) {
syslog(LOG_NOTICE,
"warning: TGT not verified (%s); %s.%s not registered, or srvtab is wrong?",
krb_get_err_text(kerror), VERIFY_SERVICE, savehost);
notickets = 0;
return (1);
}
if (kerror != KSUCCESS) {
warnx("unable to use TGT: (%s)", krb_get_err_text(kerror));
syslog(LOG_NOTICE, "unable to use TGT: (%s)",
krb_get_err_text(kerror));
dest_tkt();
return (1);
}
if (!(hp = gethostbyname(localhost))) {
syslog(LOG_ERR, "couldn't get local host address");
dest_tkt();
return (1);
}
memcpy(&faddr, hp->h_addr, sizeof(faddr));
kerror = krb_rd_req(&ticket, VERIFY_SERVICE, savehost, faddr,
&authdata, "");
if (kerror == KSUCCESS) {
notickets = 0;
return (0);
}
/* undecipherable: probably didn't have a srvtab on the local host */
if (kerror == RD_AP_UNDEC) {
syslog(LOG_NOTICE, "krb_rd_req: (%s)\n", krb_get_err_text(kerror));
dest_tkt();
return (1);
}
/* failed for some other reason */
warnx("unable to verify %s ticket: (%s)", VERIFY_SERVICE,
krb_get_err_text(kerror));
syslog(LOG_NOTICE, "couldn't verify %s ticket: %s", VERIFY_SERVICE,
krb_get_err_text(kerror));
dest_tkt();
return (1);
#else
notickets = 0;
return (0);
#endif
}
#endif
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