freebsd-skq/usr.bin/chpass/pw_yp.c
gallatin d94d9af9ee fix a serious bug where, on alpha, due to a an int/long type mismatch,
the uid arg to use_yp() was getting clobbered by the call to my_yp_match().
This led to a problem where a NIS user could edit root's passwd information.
1999-10-20 15:20:00 +00:00

541 lines
15 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
*
* $FreeBSD$
*/
#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_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;
int yp_in_pw_file = 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));
/*
* Don't make this a fatal error. The inability to contact
* a server is, for our purposes, equivalent to not finding
* the record we were looking for. Letting use_yp() know
* that the lookup failed is sufficient.
*/
if ((clnt = clnt_create(server, YPPROG,YPVERS,"udp")) == NULL) {
return(1);
#ifdef notdef
warnx("failed to create UDP handle: %s",
clnt_spcreateerror(server));
pw_error(tempname, 0, 1);
#endif
}
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);
return(1);
#ifdef notdef
warnx("%s",clnt_sperror(clnt,"YPPROC_MATCH failed"));
pw_error(tempname, 0, 1);
#endif
}
clnt_destroy(clnt);
if (ypval->stat != YP_TRUE) {
xdr_free(xdr_ypresp_val, (char *)ypval);
return(1);
#ifdef notdef
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);
#endif
}
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;
long resultlen;
char ubuf[UT_NAMESIZE + 2];
if (which) {
snprintf(ubuf, sizeof(ubuf), "%lu", (unsigned long)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;
yp_in_pw_file = !(dbp->get)(dbp,&key,&data,0);
if (_yp_check(NULL) || (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;
char *sockname = YP_SOCKNAME;
/*
* Sometimes we are called just to probe for rpc.yppasswdd and
* set the suser_override flag. Just return NULL and leave
* suser_override at 0 if _use_yp doesn't indicate that NIS is
* in use and we weren't called from use_yp() itself.
* Without this check, we might try probing and fail with an NIS
* error in non-NIS environments.
*/
if ((_use_yp == USER_UNKNOWN || _use_yp == USER_LOCAL_ONLY) &&
getserver)
return(NULL);
/* 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;
char *sockname = YP_SOCKNAME;
_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 = pw->pw_class != NULL ?
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. */
clnt = clnt_create(sockname, MASTER_YPPASSWDPROG,
MASTER_YPPASSWDVERS, "unix");
if (clnt == NULL) {
warnx("failed to contact rpc.yppasswdd: %s",
clnt_spcreateerror(master));
pw_error(tempname, 0, 1);
}
} else {
/* Create a handle to yppasswdd. */
if ((clnt = clnt_create(master, YPPASSWDPROG,
YPPASSWDVERS, "udp")) == NULL) {
warnx("failed to contact rpc.yppasswdd: %s",
clnt_spcreateerror(master));
pw_error(tempname, 0, 1);
}
}
clnt->cl_auth = authunix_create_default();
if (suser_override)
status = yppasswdproc_update_master_1(&master_yppasswd, clnt);
else
status = yppasswdproc_update_1(&yppasswd, clnt);
clnt_geterr(clnt, &err);
auth_destroy(clnt->cl_auth);
clnt_destroy(clnt);
/* Call failed: signal the error. */
if (err.re_status != RPC_SUCCESS || status == NULL || *status) {
warnx("NIS update failed: %s", clnt_sperrno(err.re_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 */