usr.bin/chpass/pw_yp.c

   1 /*
   2  * Copyright (c) 1995
   3  *      Bill Paul <wpaul@ctr.columbia.edu>.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by Bill Paul.
  16  * 4. Neither the name of the author nor the names of any co-contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  *
  32  * NIS interface routines for chpass
  33  *
  34  * Written by Bill Paul <wpaul@ctr.columbia.edu>
  35  * Center for Telecommunications Research
  36  * Columbia University, New York City
  37  *
  38  * $FreeBSD: src/usr.bin/chpass/pw_yp.c,v 1.16.2.1 2002/02/15 00:46:56 des Exp $
  39  * $DragonFly: src/usr.bin/chpass/pw_yp.c,v 1.5 2005/05/07 22:29:39 corecode Exp $
  40  */
  41
  42 #ifdef YP
  43 #include <stdio.h>
  44 #include <stdlib.h>
  45 #include <string.h>
  46 #include <netdb.h>
  47 #include <time.h>
  48 #include <sys/types.h>
  49 #include <sys/stat.h>
  50 #include <pwd.h>
  51 #include <errno.h>
  52 #include <err.h>
  53 #include <unistd.h>
  54 #include <db.h>
  55 #include <fcntl.h>
  56 #include <utmp.h>
  57 #include <sys/types.h>
  58 #include <sys/stat.h>
  59 #include <sys/param.h>
  60 #include <limits.h>
  61 #include <rpc/rpc.h>
  62 #include <rpcsvc/yp.h>
  63 struct dom_binding {};
  64 #include <rpcsvc/ypclnt.h>
  65 #include <rpcsvc/yppasswd.h>
  66 #include <pw_util.h>
  67 #include "pw_yp.h"
  68 #include "ypxfr_extern.h"
  69 #include "yppasswd_private.h"
  70
  71 #define PERM_SECURE (S_IRUSR|S_IWUSR)
  72 HASHINFO openinfo = {
  73         4096,           /* bsize */
  74         32,             /* ffactor */
  75         256,            /* nelem */
  76         2048 * 1024,    /* cachesize */
  77         NULL,           /* hash */
  78         0,              /* lorder */
  79 };
  80
  81 int force_old = 0;
  82 int _use_yp = 0;
  83 int suser_override = 0;
  84 int yp_in_pw_file = 0;
  85 char *yp_domain = NULL;
  86 char *yp_server = NULL;
  87
  88 extern char *tempname;
  89
  90 /* Save the local and NIS password information */
  91 struct passwd local_password;
  92 struct passwd yp_password;
  93
  94 void copy_yp_pass(char *p, int x, int m)
  95 {
  96         char *t, *s = p;
  97         static char *buf;
  98
  99         yp_password.pw_fields = 0;
 100
 101         buf = (char *)realloc(buf, m + 10);
 102         bzero(buf, m + 10);
 103
 104         /* Turn all colons into NULLs */
 105         while (strchr(s, ':')) {
 106                 s = (strchr(s, ':') + 1);
 107                 *(s - 1)= '\0';
 108         }
 109
 110         t = buf;
 111 #define EXPAND(e)       e = t; while ((*t++ = *p++));
 112         EXPAND(yp_password.pw_name);
 113         yp_password.pw_fields |= _PWF_NAME;
 114         EXPAND(yp_password.pw_passwd);
 115         yp_password.pw_fields |= _PWF_PASSWD;
 116         yp_password.pw_uid = atoi(p);
 117         p += (strlen(p) + 1);
 118         yp_password.pw_fields |= _PWF_UID;
 119         yp_password.pw_gid = atoi(p);
 120         p += (strlen(p) + 1);
 121         yp_password.pw_fields |= _PWF_GID;
 122         if (x) {
 123                 EXPAND(yp_password.pw_class);
 124                 yp_password.pw_fields |= _PWF_CLASS;
 125                 yp_password.pw_change = atol(p);
 126                 p += (strlen(p) + 1);
 127                 yp_password.pw_fields |= _PWF_CHANGE;
 128                 yp_password.pw_expire = atol(p);
 129                 p += (strlen(p) + 1);
 130                 yp_password.pw_fields |= _PWF_EXPIRE;
 131         }
 132         EXPAND(yp_password.pw_gecos);
 133         yp_password.pw_fields |= _PWF_GECOS;
 134         EXPAND(yp_password.pw_dir);
 135         yp_password.pw_fields |= _PWF_DIR;
 136         EXPAND(yp_password.pw_shell);
 137         yp_password.pw_fields |= _PWF_SHELL;
 138
 139         return;
 140 }
 141
 142 void copy_local_pass(char *p, int m)
 143 {
 144         char *t;
 145         static char *buf;
 146
 147         buf = (char *)realloc(buf, m + 10);
 148         bzero(buf, m + 10);
 149
 150         t = buf;
 151         EXPAND(local_password.pw_name);
 152         EXPAND(local_password.pw_passwd);
 153         bcopy(p, (char *)&local_password.pw_uid, sizeof(int));
 154         p += sizeof(int);
 155         bcopy(p, (char *)&local_password.pw_gid, sizeof(int));
 156         p += sizeof(int);
 157         bcopy(p, (char *)&local_password.pw_change, sizeof(time_t));
 158         p += sizeof(time_t);
 159         EXPAND(local_password.pw_class);
 160         EXPAND(local_password.pw_gecos);
 161         EXPAND(local_password.pw_dir);
 162         EXPAND(local_password.pw_shell);
 163         bcopy(p, (char *)&local_password.pw_expire, sizeof(time_t));
 164         p += sizeof(time_t);
 165         bcopy(p, (char *)&local_password.pw_fields, sizeof local_password.pw_fields);
 166         p += sizeof local_password.pw_fields;
 167
 168         return;
 169 }
 170
 171 /*
 172  * It is not mandatory that an NIS master server also be a client.
 173  * However, if the NIS master is not configured as a client, then the
 174  * domain name will not be set and ypbind will not be running, so we
 175  * will be unable to use the ypclnt routines inside libc. We therefore
 176  * need our own magic version of yp_match() which we can use in any
 177  * environment.
 178  */
 179 static int my_yp_match(char *server, char *domain, char *map, char *key,
 180                        unsigned long keylen, char **result, unsigned long *resultlen)
 181 {
 182         ypreq_key ypkey;
 183         ypresp_val *ypval;
 184         CLIENT *clnt;
 185         static char buf[YPMAXRECORD + 2];
 186
 187         bzero((char *)buf, sizeof(buf));
 188
 189         /*
 190          * Don't make this a fatal error. The inability to contact
 191          * a server is, for our purposes, equivalent to not finding
 192          * the record we were looking for. Letting use_yp() know
 193          * that the lookup failed is sufficient.
 194          */
 195         if ((clnt = clnt_create(server, YPPROG,YPVERS,"udp")) == NULL) {
 196                 return(1);
 197 #ifdef notdef
 198                 warnx("failed to create UDP handle: %s",
 199                                         clnt_spcreateerror(server));
 200                 pw_error(tempname, 0, 1);
 201 #endif
 202         }
 203
 204         ypkey.domain = domain;
 205         ypkey.map = map;
 206         ypkey.key.keydat_len = keylen;
 207         ypkey.key.keydat_val = key;
 208
 209         if ((ypval = ypproc_match_2(&ypkey, clnt)) == NULL) {
 210                 clnt_destroy(clnt);
 211                 return(1);
 212 #ifdef notdef
 213                 warnx("%s",clnt_sperror(clnt,"YPPROC_MATCH failed"));
 214                 pw_error(tempname, 0, 1);
 215 #endif
 216         }
 217
 218         clnt_destroy(clnt);
 219
 220         if (ypval->stat != YP_TRUE) {
 221                 xdr_free(xdr_ypresp_val, (char *)ypval);
 222                 return(1);
 223 #ifdef notdef
 224                 int stat = ypval->stat;
 225                 xdr_free(xdr_ypresp_val, (char *)ypval);
 226                 if (stat == YP_NOMAP && strstr(map, "master.passwd"))
 227                         return(1);
 228                 if (stat == YP_NOKEY)
 229                         return(1);
 230                 warnx("ypmatch failed: %s", yperr_string(ypprot_err(stat)));
 231                 pw_error(tempname, 0, 1);
 232 #endif
 233         }
 234
 235
 236         strncpy((char *)&buf, ypval->val.valdat_val, ypval->val.valdat_len);
 237
 238         *result = (char *)&buf;
 239         *resultlen = ypval->val.valdat_len;
 240
 241         xdr_free(xdr_ypresp_val, (char *)ypval);
 242
 243         return(0);
 244 }
 245
 246 /*
 247  * Check if the user we're working with is local or in NIS.
 248  */
 249 /* which: 0 = use username, 1 = use uid */
 250 int use_yp (char *user, uid_t uid, int which)
 251 {
 252         int user_local = 0, user_yp = 0, user_exists = 0;
 253         DB *dbp;
 254         DBT key,data;
 255         char bf[UT_NAMESIZE + 2];
 256         char *result;
 257         char *server;
 258         long resultlen;
 259         char ubuf[UT_NAMESIZE + 2];
 260
 261         if (which) {
 262                 snprintf(ubuf, sizeof(ubuf), "%lu", (unsigned long)uid);
 263                 user = (char *)&ubuf;
 264         }
 265
 266         /* Grope around for the user in the usual way */
 267         if (which) {
 268                 if (getpwuid(uid) != NULL)
 269                         user_exists = 1;
 270         } else {
 271                 if (getpwnam(user) != NULL)
 272                         user_exists = 1;
 273         }
 274
 275         /* Now grope directly through the user database */
 276         if ((dbp = dbopen(_PATH_SMP_DB, O_RDONLY, PERM_SECURE,
 277                         DB_HASH, &openinfo)) == NULL) {
 278                         warn("error opening database: %s.", _PATH_MP_DB);
 279                         pw_error(tempname, 0, 1);
 280         }
 281
 282         /* Is NIS turned on */
 283         bf[0] = _PW_KEYYPENABLED;
 284         key.data = (u_char *)bf;
 285         key.size = 1;
 286         yp_in_pw_file = !(dbp->get)(dbp,&key,&data,0);
 287         if (_yp_check(NULL) || (yp_domain && yp_server)) {
 288                 server = get_yp_master(0);
 289
 290                 /* Is the user in the NIS passwd map */
 291                 if (!my_yp_match(server, yp_domain, which ? "passwd.byuid" :
 292                                         "passwd.byname", user, strlen(user),
 293                     &result, &resultlen)) {
 294                         user_yp = user_exists = 1;
 295                         *(char *)(result + resultlen) = '\0';
 296                         copy_yp_pass(result, 0, resultlen);
 297                 }
 298                 /* Is the user in the NIS master.passwd map */
 299                 if (user_yp && !my_yp_match(server, yp_domain, which ?
 300                         "master.passwd.byuid" : "master.passwd.byname",
 301                     user, strlen(user),
 302                     &result, &resultlen)) {
 303                         *(char *)(result + resultlen) = '\0';
 304                         copy_yp_pass(result, 1, resultlen);
 305                 }
 306         }
 307
 308         /* Is the user in the local password database */
 309
 310         bf[0] = which ? _PW_KEYBYUID : _PW_KEYBYNAME;
 311         if (which)
 312                 bcopy((char *)&uid, bf + 1, sizeof(uid));
 313         else
 314                 bcopy((char *)user, bf + 1, MIN(strlen(user), UT_NAMESIZE));
 315         key.data = (u_char *)bf;
 316         key.size = which ? sizeof(uid) + 1 : strlen(user) + 1;
 317         if (!(dbp->get)(dbp,&key,&data,0)) {
 318                 user_local = 1;
 319                 copy_local_pass(data.data, data.size);
 320         }
 321
 322         (dbp->close)(dbp);
 323
 324         if (user_local && user_yp && user_exists)
 325                 return(USER_YP_AND_LOCAL);
 326         else if (!user_local && user_yp && user_exists)
 327                 return(USER_YP_ONLY);
 328         else if (user_local && !user_yp && user_exists)
 329                 return(USER_LOCAL_ONLY);
 330         else if (!user_exists)
 331                 return(USER_UNKNOWN);
 332
 333         return(-1);
 334 }
 335
 336 /*
 337  * Find the name of the NIS master server for this domain
 338  * and make sure it's running yppasswdd.
 339  */
 340 char *get_yp_master(int getserver)
 341 {
 342         char *mastername;
 343         int rval, localport;
 344         struct stat st;
 345         char                    *sockname = YP_SOCKNAME;
 346
 347         /*
 348          * Sometimes we are called just to probe for rpc.yppasswdd and
 349          * set the suser_override flag. Just return NULL and leave
 350          * suser_override at 0 if _use_yp doesn't indicate that NIS is
 351          * in use and we weren't called from use_yp() itself.
 352          * Without this check, we might try probing and fail with an NIS
 353          * error in non-NIS environments.
 354          */
 355         if ((_use_yp == USER_UNKNOWN || _use_yp == USER_LOCAL_ONLY) &&
 356                                                                 getserver)
 357                 return(NULL);
 358
 359         /* Get default NIS domain. */
 360
 361         if (yp_domain == NULL && (rval = yp_get_default_domain(&yp_domain))) {
 362                 warnx("can't get local NIS domain name: %s",yperr_string(rval));
 363                 pw_error(tempname, 0, 1);
 364         }
 365
 366         /* Get master server of passwd map. */
 367
 368         if ((mastername = ypxfr_get_master(yp_domain, "passwd.byname",
 369                                 yp_server, yp_server ? 0 : 1)) == NULL) {
 370                 warnx("can't get name of master NIS server");
 371                 pw_error(tempname, 0, 1);
 372         }
 373
 374         if (!getserver)
 375                 return(mastername);
 376
 377         /* Check if yppasswdd is out there. */
 378
 379         if ((rval = getrpcport(mastername, YPPASSWDPROG, YPPASSWDPROC_UPDATE,
 380                 IPPROTO_UDP)) == 0) {
 381                 warnx("rpc.yppasswdd is not running on the NIS master server");
 382                 pw_error(tempname, 0, 1);
 383         }
 384
 385         /*
 386          * Make sure it's on a reserved port.
 387          * XXX Might break with yppasswdd servers running on Solaris 2.x.
 388          */
 389
 390         if (rval >= IPPORT_RESERVED) {
 391                 warnx("rpc.yppasswdd server not running on reserved port");
 392                 pw_error(tempname, 0, 1);
 393         }
 394
 395         /* See if _we_ are the master server. */
 396         if (!force_old && !getuid() && (localport = getrpcport("localhost",
 397                 YPPASSWDPROG, YPPASSWDPROC_UPDATE, IPPROTO_UDP)) != 0) {
 398                 if (localport == rval && stat(sockname, &st) != -1) {
 399                         suser_override = 1;
 400                         mastername = "localhost";
 401                 }
 402         }
 403
 404         /* Everything checks out: return the name of the server. */
 405
 406         return (mastername);
 407 }
 408
 409 /*
 410  * Ask the user for his NIS password and submit the new information
 411  * to yppasswdd. Note that rpc.yppasswdd requires password authentication
 412  * and only allows changes to existing records rather than the addition
 413  * of new records. (To do actual updates we would need something like
 414  * secure RPC and ypupdated, which FreeBSD doesn't have yet.) The FreeBSD
 415  * rpc.yppasswdd has some special hooks to allow the superuser update
 416  * information without specifying a password, however this only works
 417  * for the superuser on the NIS master server.
 418  */
 419 void yp_submit(struct passwd *pw)
 420 {
 421         struct yppasswd yppasswd;
 422         struct master_yppasswd master_yppasswd;
 423         CLIENT *clnt;
 424         char *master, *password;
 425         int *status = NULL;
 426         struct rpc_err err;
 427         char                    *sockname = YP_SOCKNAME;
 428
 429         _use_yp = 1;
 430
 431         /* Get NIS master server name */
 432
 433         master = get_yp_master(1);
 434
 435         /* Populate the yppasswd structure that gets handed to yppasswdd. */
 436
 437         if (suser_override) {
 438                 master_yppasswd.newpw.pw_passwd = strdup(pw->pw_passwd);
 439                 master_yppasswd.newpw.pw_name = strdup(pw->pw_name);
 440                 master_yppasswd.newpw.pw_uid = pw->pw_uid;
 441                 master_yppasswd.newpw.pw_gid = pw->pw_gid;
 442                 master_yppasswd.newpw.pw_expire = pw->pw_expire;
 443                 master_yppasswd.newpw.pw_change = pw->pw_change;
 444                 master_yppasswd.newpw.pw_fields = pw->pw_fields;
 445                 master_yppasswd.newpw.pw_gecos = strdup(pw->pw_gecos);
 446                 master_yppasswd.newpw.pw_dir = strdup(pw->pw_dir);
 447                 master_yppasswd.newpw.pw_shell = strdup(pw->pw_shell);
 448                 master_yppasswd.newpw.pw_class = pw->pw_class != NULL ?
 449                                                 strdup(pw->pw_class) : "";
 450                 master_yppasswd.oldpass = ""; /* not really needed */
 451                 master_yppasswd.domain = yp_domain;
 452         } else {
 453                 yppasswd.newpw.pw_passwd = strdup(pw->pw_passwd);
 454                 yppasswd.newpw.pw_name = strdup(pw->pw_name);
 455                 yppasswd.newpw.pw_uid = pw->pw_uid;
 456                 yppasswd.newpw.pw_gid = pw->pw_gid;
 457                 yppasswd.newpw.pw_gecos = strdup(pw->pw_gecos);
 458                 yppasswd.newpw.pw_dir = strdup(pw->pw_dir);
 459                 yppasswd.newpw.pw_shell = strdup(pw->pw_shell);
 460                 yppasswd.oldpass = "";
 461         }
 462
 463         /* Get the user's password for authentication purposes. */
 464
 465         printf ("Changing NIS information for %s on %s\n",
 466                                         pw->pw_name, master);
 467
 468         if (pw->pw_passwd[0] && !suser_override) {
 469                 password = getpass("Please enter password: ");
 470                 if (strncmp(crypt(password,pw->pw_passwd),
 471                                 pw->pw_passwd,strlen(pw->pw_passwd))) {
 472                         warnx("Password incorrect.");
 473                         pw_error(tempname, 0, 1);
 474                 }
 475                 yppasswd.oldpass = password;    /* XXX */
 476         }
 477
 478         if (suser_override) {
 479                 /* Talk to server via AF_UNIX socket. */
 480                 clnt = clnt_create(sockname, MASTER_YPPASSWDPROG,
 481                                         MASTER_YPPASSWDVERS, "unix");
 482                 if (clnt == NULL) {
 483                         warnx("failed to contact rpc.yppasswdd: %s",
 484                                 clnt_spcreateerror(master));
 485                         pw_error(tempname, 0, 1);
 486                 }
 487         } else {
 488                 /* Create a handle to yppasswdd. */
 489
 490                 if ((clnt = clnt_create(master, YPPASSWDPROG,
 491                                         YPPASSWDVERS, "udp")) == NULL) {
 492                         warnx("failed to contact rpc.yppasswdd: %s",
 493                                 clnt_spcreateerror(master));
 494                         pw_error(tempname, 0, 1);
 495                 }
 496         }
 497
 498         clnt->cl_auth = authunix_create_default();
 499
 500         if (suser_override)
 501                 status = yppasswdproc_update_master_1(&master_yppasswd, clnt);
 502         else
 503                 status = yppasswdproc_update_1(&yppasswd, clnt);
 504
 505         clnt_geterr(clnt, &err);
 506
 507         auth_destroy(clnt->cl_auth);
 508         clnt_destroy(clnt);
 509
 510         /* Call failed: signal the error. */
 511
 512         if (err.re_status != RPC_SUCCESS || status == NULL || *status) {
 513                 warnx("NIS update failed: %s", clnt_sperrno(err.re_status));
 514                 pw_error(NULL, 0, 1);
 515         }
 516
 517         /* Success. */
 518
 519         if (suser_override)
 520                 warnx("NIS information changed on host %s, domain %s",
 521                         master, yp_domain);
 522         else
 523                 warnx("NIS information changed on host %s", master);
 524
 525         return;
 526 }
 527 #endif /* YP */