freebsd-dev/usr.bin/chpass/pw_yp.c
Bill Paul c2dfe9fe01 Merge in changes to support the new rpc.yppasswdd(8) and fix a few bugs.
In passwd(1):

- Gut most of yp_passwd.c and leave only a few things that aren't common
  to pw_yp.c.

- Add support for -d and -h flags to select domains and NIS server hosts
  to use when updating NIS passwords. This allows passwd(1) to be used
  for changing NIS passwords from machines that aren't configured as
  NIS clients. (This is mostly to allow passwd(1) to work on NIS master
  servers that aren't configured as clients -- an NIS server need not
  necessarily be configured as a client itself.)

  NOTE: Realize that having the ability to specify a domain and hostname
  lets you use passwd(1) (and chpass(1) too) to submit update requests
  to yppasswd daemons running on remote servers in remote domains which
  you may not even be bound to. For example, my machine at home is not
  an NIS client of the servers on the network that I manage, yet I can
  easily change my password at work using my FreeBSD box at home by doing:
  'passwd -d work.net.domain -h any.nis.server.on.my.net wpaul'. (Yes,
  I do use securenets at work; temporarily modified my securenets file
  to give my home system access.) Some people may not be too thrilled
  with this idea. Those who don't like this feature can recompile passwd(1)
  and chpass(1) with -DPARANOID to restrict the use of these flags to
  the superuser.

  (Oh, I should be adding proper securenets support to ypserv(8) and
  rpc.yppasswdd(8) over the weekend.)

- Merge in changes to allow root on the NIS master server to bypass
  authentication and change any user's NIS password. (The super-user
  on the NIS master already has privileges to do this, but doing it
  through passwd(1) is much easier than updating the maps by hand.)
  Note that passwd(1) communicates with rpc.yppasswdd(8) via a UNIX
  domain socket instead of via standard RPC/IP in this case.

- Update man page.

In chpass(1):

- Fix pw_yp.c to work properly in environments where NIS client
  services aren't available.

- Use realloc() instead of malloc() in copy_yp_pass() and copy_local_pass().

- Fix silly bug in copy_yp_pass(); some of the members of the passwd
  structure weren't being filled in correctly. (This went unnoticed
  for a while since the old yppasswdd didn't allow changes to the
  fields that were being botched.)

- chpass(1) now also allows the superuser on the NIS master server to
  make unrestricted changes to any user's NIS password information.

- Use UNIX domain comm channel to rpc.yppasswdd(8) when run by the
  superuser on the NIS master. This allows several new things:

   o superuser can update an entire master.passwd.{byname,byuid} entry
   o superuser can update records in arbitrary domains using -d flag to
     select a domain (before you could only change the default domain)
   o superuser can _add_ records to the NIS master.passwd maps, provided
     rpc.yppasswdd(8) has been started with the -a flag (to do this,
     the superuser must force NIS operation by specifying the -y flag
     to chpass(1) along with -a, i.e. 'chpass -y -a 'foo:::::::::')

- Back out the 'chpass -a <new password entry> breaks with NIS' fix
  from the last revision and fix it properly this time. The previous
  revision fixed the immediate problem but broke NIS operation in
  some cases.

- In edit.c, be a little more reasonable about deciding when to
  prevent the shell field from being changed.

  Submitted by Charles Owens <owensc@enc.edu>, who said:

  "I made a minor (one-line) modification to chpass, with regards
   to whether or not it allows the changing of shells.  In the 2.0.5 code,
   field changing follows the settings specified in the "list" structure
   defined in table.c .  For the shell, though, this is ignored.  A quick
   look in edit.c showed me why, but I don't understand why it was written as
   such.  The logic was

        if shell is standard shell, allow changing

   I changed it to

        if shell changing is allowed (per table.c) and it is a standard shell
             OR if uid=0, then allow changing."

   Makes sense to me.

- Update man page.
1996-02-23 16:08:59 +00:00

505 lines
14 KiB
C

/*
* Copyright (c) 1995
* Bill Paul <wpaul@ctr.columbia.edu>. 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 Bill Paul.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY Bill Paul 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 Bill Paul 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.
*
* NIS interface routines for chpass
*
* Written by Bill Paul <wpaul@ctr.columbia.edu>
* Center for Telecommunications Research
* Columbia University, New York City
*
* $Id: pw_yp.c,v 1.9 1996/02/23 04:20:19 wpaul Exp $
*/
#ifdef YP
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <netdb.h>
#include <time.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <pwd.h>
#include <errno.h>
#include <err.h>
#include <unistd.h>
#include <db.h>
#include <fcntl.h>
#include <utmp.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/param.h>
#include <limits.h>
#include <rpc/rpc.h>
#include <rpcsvc/yp.h>
struct dom_binding {};
#include <rpcsvc/ypclnt.h>
#include <rpcsvc/yppasswd.h>
#include <pw_util.h>
#include "pw_yp.h"
#include "ypxfr_extern.h"
#include "yppasswd_comm.h"
#include "yppasswd_private.h"
#define PERM_SECURE (S_IRUSR|S_IWUSR)
static HASHINFO openinfo = {
4096, /* bsize */
32, /* ffactor */
256, /* nelem */
2048 * 1024, /* cachesize */
NULL, /* hash */
0, /* lorder */
};
int force_old = 0;
int _use_yp = 0;
int suser_override = 0;
char *yp_domain = NULL;
char *yp_server = NULL;
extern char *tempname;
/* Save the local and NIS password information */
struct passwd local_password;
struct passwd yp_password;
void copy_yp_pass(p, x, m)
char *p;
int x, m;
{
register char *t, *s = p;
static char *buf;
yp_password.pw_fields = 0;
buf = (char *)realloc(buf, m + 10);
bzero(buf, m + 10);
/* Turn all colons into NULLs */
while (strchr(s, ':')) {
s = (strchr(s, ':') + 1);
*(s - 1)= '\0';
}
t = buf;
#define EXPAND(e) e = t; while ((*t++ = *p++));
EXPAND(yp_password.pw_name);
yp_password.pw_fields |= _PWF_NAME;
EXPAND(yp_password.pw_passwd);
yp_password.pw_fields |= _PWF_PASSWD;
yp_password.pw_uid = atoi(p);
p += (strlen(p) + 1);
yp_password.pw_fields |= _PWF_UID;
yp_password.pw_gid = atoi(p);
p += (strlen(p) + 1);
yp_password.pw_fields |= _PWF_GID;
if (x) {
EXPAND(yp_password.pw_class);
yp_password.pw_fields |= _PWF_CLASS;
yp_password.pw_change = atol(p);
p += (strlen(p) + 1);
yp_password.pw_fields |= _PWF_CHANGE;
yp_password.pw_expire = atol(p);
p += (strlen(p) + 1);
yp_password.pw_fields |= _PWF_EXPIRE;
}
EXPAND(yp_password.pw_gecos);
yp_password.pw_fields |= _PWF_GECOS;
EXPAND(yp_password.pw_dir);
yp_password.pw_fields |= _PWF_DIR;
EXPAND(yp_password.pw_shell);
yp_password.pw_fields |= _PWF_SHELL;
return;
}
void copy_local_pass(p,m)
char *p;
int m;
{
register char *t;
static char *buf;
buf = (char *)realloc(buf, m + 10);
bzero(buf, m + 10);
t = buf;
EXPAND(local_password.pw_name);
EXPAND(local_password.pw_passwd);
bcopy(p, (char *)&local_password.pw_uid, sizeof(int));
p += sizeof(int);
bcopy(p, (char *)&local_password.pw_gid, sizeof(int));
p += sizeof(int);
bcopy(p, (char *)&local_password.pw_change, sizeof(time_t));
p += sizeof(time_t);
EXPAND(local_password.pw_class);
EXPAND(local_password.pw_gecos);
EXPAND(local_password.pw_dir);
EXPAND(local_password.pw_shell);
bcopy(p, (char *)&local_password.pw_expire, sizeof(time_t));
p += sizeof(time_t);
bcopy(p, (char *)&local_password.pw_fields, sizeof local_password.pw_fields);
p += sizeof local_password.pw_fields;
return;
}
/*
* It is not mandatory that an NIS master server also be a client.
* However, if the NIS master is not configured as a client, then the
* domain name will not be set and ypbind will not be running, so we
* will be unable to use the ypclnt routines inside libc. We therefore
* need our own magic version of yp_match() which we can use in any
* environment.
*/
static int my_yp_match(server, domain, map, key, keylen, result, resultlen)
char *server;
char *domain;
char *map;
char *key;
unsigned long keylen;
char **result;
unsigned long *resultlen;
{
ypreq_key ypkey;
ypresp_val *ypval;
CLIENT *clnt;
static char buf[YPMAXRECORD + 2];
bzero((char *)buf, sizeof(buf));
if ((clnt = clnt_create(server, YPPROG,YPVERS,"udp")) == NULL) {
warnx("%s", clnt_spcreateerror("failed to create handle"));
pw_error(tempname, 0, 1);
}
ypkey.domain = domain;
ypkey.map = map;
ypkey.key.keydat_len = keylen;
ypkey.key.keydat_val = key;
if ((ypval = ypproc_match_2(&ypkey, clnt)) == NULL) {
clnt_destroy(clnt);
warnx("%s",clnt_sperror(clnt,"YPPROC_MATCH failed"));
pw_error(tempname, 0, 1);
}
clnt_destroy(clnt);
if (ypval->stat != YP_TRUE) {
int stat = ypval->stat;
xdr_free(xdr_ypresp_val, (char *)ypval);
if (stat == YP_NOMAP && strstr(map, "master.passwd"))
return(1);
if (stat == YP_NOKEY)
return(1);
warnx("ypmatch failed: %s", yperr_string(ypprot_err(stat)));
pw_error(tempname, 0, 1);
}
strncpy((char *)&buf, ypval->val.valdat_val, ypval->val.valdat_len);
*result = (char *)&buf;
*resultlen = ypval->val.valdat_len;
xdr_free(xdr_ypresp_val, (char *)ypval);
return(0);
}
/*
* Check if the user we're working with is local or in NIS.
*/
int use_yp (user, uid, which)
char *user;
uid_t uid;
int which; /* 0 = use username, 1 = use uid */
{
int user_local = 0, user_yp = 0, user_exists = 0;
DB *dbp;
DBT key,data;
char bf[UT_NAMESIZE + 2];
char *result;
char *server;
int resultlen;
char ubuf[UT_NAMESIZE + 2];
if (which) {
snprintf(ubuf, sizeof(ubuf), "%lu", uid);
user = (char *)&ubuf;
}
/* Grope around for the user in the usual way */
if (which) {
if (getpwuid(uid) != NULL)
user_exists = 1;
} else {
if (getpwnam(user) != NULL)
user_exists = 1;
}
/* Now grope directly through the user database */
if ((dbp = dbopen(_PATH_SMP_DB, O_RDONLY, PERM_SECURE,
DB_HASH, &openinfo)) == NULL) {
warn("error opening database: %s.", _PATH_MP_DB);
pw_error(tempname, 0, 1);
}
/* Is NIS turned on */
bf[0] = _PW_KEYYPENABLED;
key.data = (u_char *)bf;
key.size = 1;
if (!(dbp->get)(dbp,&key,&data,0) || (yp_domain && yp_server)) {
server = get_yp_master(0);
/* Is the user in the NIS passwd map */
if (!my_yp_match(server, yp_domain, which ? "passwd.byuid" :
"passwd.byname", user, strlen(user),
&result, &resultlen)) {
user_yp = user_exists = 1;
*(char *)(result + resultlen) = '\0';
copy_yp_pass(result, 0, resultlen);
}
/* Is the user in the NIS master.passwd map */
if (user_yp && !my_yp_match(server, yp_domain, which ?
"master.passwd.byuid" : "master.passwd.byname",
user, strlen(user),
&result, &resultlen)) {
*(char *)(result + resultlen) = '\0';
copy_yp_pass(result, 1, resultlen);
}
}
/* Is the user in the local password database */
bf[0] = which ? _PW_KEYBYUID : _PW_KEYBYNAME;
if (which)
bcopy((char *)&uid, bf + 1, sizeof(uid));
else
bcopy((char *)user, bf + 1, MIN(strlen(user), UT_NAMESIZE));
key.data = (u_char *)bf;
key.size = which ? sizeof(uid) + 1 : strlen(user) + 1;
if (!(dbp->get)(dbp,&key,&data,0)) {
user_local = 1;
copy_local_pass(data.data, data.size);
}
(dbp->close)(dbp);
if (user_local && user_yp && user_exists)
return(USER_YP_AND_LOCAL);
else if (!user_local && user_yp && user_exists)
return(USER_YP_ONLY);
else if (user_local && !user_yp && user_exists)
return(USER_LOCAL_ONLY);
else if (!user_exists)
return(USER_UNKNOWN);
return(-1);
}
/*
* Find the name of the NIS master server for this domain
* and make sure it's running yppasswdd.
*/
char *get_yp_master(getserver)
int getserver;
{
char *mastername;
int rval, localport;
struct stat st;
/* Get default NIS domain. */
if (yp_domain == NULL && (rval = yp_get_default_domain(&yp_domain))) {
warnx("can't get local NIS domain name: %s",yperr_string(rval));
pw_error(tempname, 0, 1);
}
/* Get master server of passwd map. */
if ((mastername = ypxfr_get_master(yp_domain, "passwd.byname",
yp_server, yp_server ? 0 : 1)) == NULL) {
warnx("can't get name of master NIS server");
pw_error(tempname, 0, 1);
}
if (!getserver)
return(mastername);
/* Check if yppasswdd is out there. */
if ((rval = getrpcport(mastername, YPPASSWDPROG, YPPASSWDPROC_UPDATE,
IPPROTO_UDP)) == 0) {
warnx("rpc.yppasswdd is not running on the NIS master server");
pw_error(tempname, 0, 1);
}
/*
* Make sure it's on a reserved port.
* XXX Might break with yppasswdd servers running on Solaris 2.x.
*/
if (rval >= IPPORT_RESERVED) {
warnx("rpc.yppasswdd server not running on reserved port");
pw_error(tempname, 0, 1);
}
/* See if _we_ are the master server. */
if (!force_old && !getuid() && (localport = getrpcport("localhost",
YPPASSWDPROG, YPPASSWDPROC_UPDATE, IPPROTO_UDP)) != 0) {
if (localport == rval && stat(sockname, &st) != -1) {
suser_override = 1;
mastername = "localhost";
}
}
/* Everything checks out: return the name of the server. */
return (mastername);
}
/*
* Ask the user for his NIS password and submit the new information
* to yppasswdd. Note that rpc.yppasswdd requires password authentication
* and only allows changes to existing records rather than the addition
* of new records. (To do actual updates we would need something like
* secure RPC and ypupdated, which FreeBSD doesn't have yet.) The FreeBSD
* rpc.yppasswdd has some special hooks to allow the superuser update
* information without specifying a password, however this only works
* for the superuser on the NIS master server.
*/
void yp_submit(pw)
struct passwd *pw;
{
struct yppasswd yppasswd;
struct master_yppasswd master_yppasswd;
CLIENT *clnt;
char *master, *password;
int *status = NULL;
struct rpc_err err;
_use_yp = 1;
/* Get NIS master server name */
master = get_yp_master(1);
/* Populate the yppasswd structure that gets handed to yppasswdd. */
if (suser_override) {
master_yppasswd.newpw.pw_passwd = strdup(pw->pw_passwd);
master_yppasswd.newpw.pw_name = strdup(pw->pw_name);
master_yppasswd.newpw.pw_uid = pw->pw_uid;
master_yppasswd.newpw.pw_gid = pw->pw_gid;
master_yppasswd.newpw.pw_expire = pw->pw_expire;
master_yppasswd.newpw.pw_change = pw->pw_change;
master_yppasswd.newpw.pw_fields = pw->pw_fields;
master_yppasswd.newpw.pw_gecos = strdup(pw->pw_gecos);
master_yppasswd.newpw.pw_dir = strdup(pw->pw_dir);
master_yppasswd.newpw.pw_shell = strdup(pw->pw_shell);
master_yppasswd.newpw.pw_class = strdup(pw->pw_class);
master_yppasswd.oldpass = ""; /* not really needed */
master_yppasswd.domain = yp_domain;
} else {
yppasswd.newpw.pw_passwd = strdup(pw->pw_passwd);
yppasswd.newpw.pw_name = strdup(pw->pw_name);
yppasswd.newpw.pw_uid = pw->pw_uid;
yppasswd.newpw.pw_gid = pw->pw_gid;
yppasswd.newpw.pw_gecos = strdup(pw->pw_gecos);
yppasswd.newpw.pw_dir = strdup(pw->pw_dir);
yppasswd.newpw.pw_shell = strdup(pw->pw_shell);
yppasswd.oldpass = "";
}
/* Get the user's password for authentication purposes. */
printf ("Changing NIS information for %s on %s\n",
pw->pw_name, master);
if (pw->pw_passwd[0] && !suser_override) {
password = getpass("Please enter password: ");
if (strncmp(crypt(password,pw->pw_passwd),
pw->pw_passwd,strlen(pw->pw_passwd))) {
warnx("Password incorrect.");
pw_error(tempname, 0, 1);
}
yppasswd.oldpass = password; /* XXX */
}
if (suser_override) {
/* Talk to server via AF_UNIX socket. */
if (senddat(&master_yppasswd)) {
warnx("failed to contact local rpc.yppasswdd");
pw_error(tempname, 0, 1);
}
/* Get return code. */
status = getresp();
} else {
/* Create a handle to yppasswdd. */
if ((clnt = clnt_create(master, YPPASSWDPROG,
YPPASSWDVERS, "udp")) == NULL) {
warnx("failed to contact rpc.yppasswdd on %s: %s",
master, clnt_spcreateerror(""));
pw_error(tempname, 0, 1);
}
clnt->cl_auth = authunix_create_default();
status = yppasswdproc_update_1(&yppasswd, clnt);
clnt_geterr(clnt, &err);
auth_destroy(clnt->cl_auth);
clnt_destroy(clnt);
}
/* Call failed: signal the error. */
if ((!suser_override && err.re_status) != RPC_SUCCESS || status == NULL || *status) {
warnx("NIS update failed: %s", (err.re_status != RPC_SUCCESS &&
!suser_override) ? clnt_sperrno(err.re_status) :
"rpc.yppasswdd returned error status");
pw_error(NULL, 0, 1);
}
/* Success. */
if (suser_override)
warnx("NIS information changed on host %s, domain %s",
master, yp_domain);
else
warnx("NIS information changed on host %s", master);
return;
}
#endif /* YP */