1 /* 2 * Copyright (c) 1995, 1996 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 * $FreeBSD: src/usr.sbin/rpc.yppasswdd/yppasswdd_server.c,v 1.29 2003/06/15 21:24:45 mbr Exp $ 33 * $DragonFly: src/usr.sbin/rpc.yppasswdd/yppasswdd_server.c,v 1.7 2005/11/25 00:32:49 swildner Exp $ 34 */ 35 36 #include <sys/param.h> 37 #include <sys/fcntl.h> 38 #include <sys/socket.h> 39 #include <sys/stat.h> 40 #include <sys/wait.h> 41 42 #include <arpa/inet.h> 43 #include <netinet/in.h> 44 45 #include <ctype.h> 46 #include <db.h> 47 #include <dirent.h> 48 #include <errno.h> 49 #include <limits.h> 50 #include <pwd.h> 51 #include <signal.h> 52 #include <stdio.h> 53 #include <stdlib.h> 54 #include <string.h> 55 #include <unistd.h> 56 57 #include <libgen.h> 58 #include <libutil.h> 59 60 #include <rpc/rpc.h> 61 #include <rpcsvc/yp.h> 62 struct dom_binding; 63 #include <rpcsvc/ypclnt.h> 64 #include "yppasswdd_extern.h" 65 #include "yppasswd.h" 66 #include "yppasswd_private.h" 67 #include "ypxfr_extern.h" 68 #include "yp_extern.h" 69 70 static struct passwd yp_password; 71 72 static void 73 copy_yp_pass(char *p, int x, int m) 74 { 75 char *t, *s = p; 76 static char *buf; 77 78 yp_password.pw_fields = 0; 79 80 buf = realloc(buf, m + 10); 81 bzero(buf, m + 10); 82 83 /* Turn all colons into NULLs */ 84 while (strchr(s, ':')) { 85 s = (strchr(s, ':') + 1); 86 *(s - 1)= '\0'; 87 } 88 89 t = buf; 90 #define EXPAND(e) e = t; while ((*t++ = *p++)); 91 EXPAND(yp_password.pw_name); 92 yp_password.pw_fields |= _PWF_NAME; 93 EXPAND(yp_password.pw_passwd); 94 yp_password.pw_fields |= _PWF_PASSWD; 95 yp_password.pw_uid = atoi(p); 96 p += (strlen(p) + 1); 97 yp_password.pw_fields |= _PWF_UID; 98 yp_password.pw_gid = atoi(p); 99 p += (strlen(p) + 1); 100 yp_password.pw_fields |= _PWF_GID; 101 if (x) { 102 EXPAND(yp_password.pw_class); 103 yp_password.pw_fields |= _PWF_CLASS; 104 yp_password.pw_change = atol(p); 105 p += (strlen(p) + 1); 106 yp_password.pw_fields |= _PWF_CHANGE; 107 yp_password.pw_expire = atol(p); 108 p += (strlen(p) + 1); 109 yp_password.pw_fields |= _PWF_EXPIRE; 110 } 111 EXPAND(yp_password.pw_gecos); 112 yp_password.pw_fields |= _PWF_GECOS; 113 EXPAND(yp_password.pw_dir); 114 yp_password.pw_fields |= _PWF_DIR; 115 EXPAND(yp_password.pw_shell); 116 yp_password.pw_fields |= _PWF_SHELL; 117 118 return; 119 } 120 121 static int 122 validchars(char *arg) 123 { 124 size_t i; 125 126 for (i = 0; i < strlen(arg); i++) { 127 if (iscntrl(arg[i])) { 128 yp_error("string contains a control character"); 129 return(1); 130 } 131 if (arg[i] == ':') { 132 yp_error("string contains a colon"); 133 return(1); 134 } 135 /* Be evil: truncate strings with \n in them silently. */ 136 if (arg[i] == '\n') { 137 arg[i] = '\0'; 138 return(0); 139 } 140 } 141 return(0); 142 } 143 144 static int 145 validate_master(struct passwd *opw __unused, struct x_master_passwd *npw) 146 { 147 148 if (npw->pw_name[0] == '+' || npw->pw_name[0] == '-') { 149 yp_error("client tried to modify an NIS entry"); 150 return(1); 151 } 152 153 if (validchars(npw->pw_shell)) { 154 yp_error("specified shell contains invalid characters"); 155 return(1); 156 } 157 158 if (validchars(npw->pw_gecos)) { 159 yp_error("specified gecos field contains invalid characters"); 160 return(1); 161 } 162 163 if (validchars(npw->pw_passwd)) { 164 yp_error("specified password contains invalid characters"); 165 return(1); 166 } 167 return(0); 168 } 169 170 static int 171 validate(struct passwd *opw, struct x_passwd *npw) 172 { 173 174 if (npw->pw_name[0] == '+' || npw->pw_name[0] == '-') { 175 yp_error("client tried to modify an NIS entry"); 176 return(1); 177 } 178 179 if ((uid_t)npw->pw_uid != opw->pw_uid) { 180 yp_error("UID mismatch: client says user %s has UID %d", 181 npw->pw_name, npw->pw_uid); 182 yp_error("database says user %s has UID %d", opw->pw_name, 183 opw->pw_uid); 184 return(1); 185 } 186 187 if ((gid_t)npw->pw_gid != opw->pw_gid) { 188 yp_error("GID mismatch: client says user %s has GID %d", 189 npw->pw_name, npw->pw_gid); 190 yp_error("database says user %s has GID %d", opw->pw_name, 191 opw->pw_gid); 192 return(1); 193 } 194 195 /* 196 * Don't allow the user to shoot himself in the foot, 197 * even on purpose. 198 */ 199 if (!ok_shell(npw->pw_shell)) { 200 yp_error("%s is not a valid shell", npw->pw_shell); 201 return(1); 202 } 203 204 if (validchars(npw->pw_shell)) { 205 yp_error("specified shell contains invalid characters"); 206 return(1); 207 } 208 209 if (validchars(npw->pw_gecos)) { 210 yp_error("specified gecos field contains invalid characters"); 211 return(1); 212 } 213 214 if (validchars(npw->pw_passwd)) { 215 yp_error("specified password contains invalid characters"); 216 return(1); 217 } 218 return(0); 219 } 220 221 /* 222 * Kludge alert: 223 * In order to have one rpc.yppasswdd support multiple domains, 224 * we have to cheat: we search each directory under /var/yp 225 * and try to match the user in each master.passwd.byname 226 * map that we find. If the user matches (username, uid and gid 227 * all agree), then we use that domain. If we match the user in 228 * more than one database, we must abort. 229 */ 230 static char * 231 find_domain(struct x_passwd *pw) 232 { 233 struct stat statbuf; 234 struct dirent *dirp; 235 DIR *dird; 236 char yp_mapdir[MAXPATHLEN + 2]; 237 static char domain[YPMAXDOMAIN]; 238 char *tmp = NULL; 239 DBT key, data; 240 int hit = 0; 241 242 yp_error("performing multidomain lookup"); 243 244 if ((dird = opendir(yp_dir)) == NULL) { 245 yp_error("opendir(%s) failed: %s", yp_dir, strerror(errno)); 246 return(NULL); 247 } 248 249 while ((dirp = readdir(dird)) != NULL) { 250 snprintf(yp_mapdir, sizeof yp_mapdir, "%s/%s", 251 yp_dir, dirp->d_name); 252 if (stat(yp_mapdir, &statbuf) < 0) { 253 yp_error("stat(%s) failed: %s", yp_mapdir, 254 strerror(errno)); 255 closedir(dird); 256 return(NULL); 257 } 258 if (S_ISDIR(statbuf.st_mode)) { 259 tmp = (char *)dirp->d_name; 260 key.data = pw->pw_name; 261 key.size = strlen(pw->pw_name); 262 263 if (yp_get_record(tmp,"master.passwd.byname", 264 &key, &data, 0) != YP_TRUE) { 265 continue; 266 } 267 *((char *)data.data + data.size) = '\0'; 268 copy_yp_pass(data.data, 1, data.size); 269 if (yp_password.pw_uid == (uid_t)pw->pw_uid && 270 yp_password.pw_gid == (gid_t)pw->pw_gid) { 271 hit++; 272 snprintf(domain, YPMAXDOMAIN, "%s", tmp); 273 } 274 } 275 } 276 277 closedir(dird); 278 if (hit > 1) { 279 yp_error("found same user in two different domains"); 280 return(NULL); 281 } else 282 return((char *)&domain); 283 } 284 285 static const char *maps[] = { 286 "master.passwd.byname", 287 "master.passwd.byuid", 288 "passwd.byname", 289 "passwd.byuid" 290 }; 291 292 static const char *formats[] = { 293 "%s:%s:%d:%d:%s:%ld:%ld:%s:%s:%s", 294 "%s:%s:%d:%d:%s:%ld:%ld:%s:%s:%s", 295 "%s:%s:%d:%d:%s:%s:%s", 296 "%s:%s:%d:%d:%s:%s:%s" 297 }; 298 299 static int 300 update_inplace(struct passwd *pw, char *domain) 301 { 302 DB *dbp = NULL; 303 DBT key = { NULL, 0 }; 304 DBT data = { NULL, 0 }; 305 char pwbuf[YPMAXRECORD]; 306 char keybuf[20]; 307 int i; 308 char *ptr = NULL; 309 static char yp_last[] = "YP_LAST_MODIFIED"; 310 char yplastbuf[YPMAXRECORD]; 311 312 snprintf(yplastbuf, sizeof yplastbuf, "%llu", 313 (unsigned long long)time(NULL)); 314 315 for (i = 0; i < 4; i++) { 316 317 if (i % 2) { 318 snprintf(keybuf, sizeof keybuf, 319 "%llu", (unsigned long long)pw->pw_uid); 320 key.data = &keybuf; 321 key.size = strlen(keybuf); 322 } else { 323 key.data = pw->pw_name; 324 key.size = strlen(pw->pw_name); 325 } 326 327 /* 328 * XXX The passwd.byname and passwd.byuid maps come in 329 * two flavors: secure and insecure. The secure version 330 * has a '*' in the password field whereas the insecure one 331 * has a real crypted password. The maps will be insecure 332 * if they were built with 'unsecure = TRUE' enabled in 333 * /var/yp/Makefile, but we'd have no way of knowing if 334 * this has been done unless we were to try parsing the 335 * Makefile, which is a disgusting thought. Instead, we 336 * read the records from the maps, skip to the first ':' 337 * in them, and then look at the character immediately 338 * following it. If it's an '*' then the map is 'secure' 339 * and we must not insert a real password into the pw_passwd 340 * field. If it's not an '*', then we put the real crypted 341 * password in. 342 */ 343 if (yp_get_record(domain,maps[i],&key,&data,1) != YP_TRUE) { 344 yp_error("couldn't read %s/%s: %s", domain, 345 maps[i], strerror(errno)); 346 return(1); 347 } 348 349 if ((ptr = strchr(data.data, ':')) == NULL) { 350 yp_error("no colon in passwd record?!"); 351 return(1); 352 } 353 354 /* 355 * XXX Supposing we have more than one user with the same 356 * UID? (Or more than one user with the same name?) We could 357 * end up modifying the wrong record if were not careful. 358 */ 359 if (i % 2) { 360 if (strncmp(data.data, pw->pw_name, 361 strlen(pw->pw_name))) { 362 yp_error("warning: found entry for UID %d " 363 "in map %s@%s with wrong name (%.*s)", 364 pw->pw_uid, maps[i], domain, 365 (int)(ptr - (char *)data.data), 366 (char *)data.data); 367 yp_error("there may be more than one user " 368 "with the same UID - continuing"); 369 continue; 370 } 371 } else { 372 /* 373 * We're really being ultra-paranoid here. 374 * This is generally a 'can't happen' condition. 375 */ 376 snprintf(pwbuf, sizeof pwbuf, ":%d:%d:", pw->pw_uid, 377 pw->pw_gid); 378 if (!strstr(data.data, pwbuf)) { 379 yp_error("warning: found entry for user %s \ 380 in map %s@%s with wrong UID", pw->pw_name, maps[i], domain); 381 yp_error("there may be more than one user \ 382 with the same name - continuing"); 383 continue; 384 } 385 } 386 387 if (i < 2) { 388 snprintf(pwbuf, sizeof pwbuf, formats[i], 389 pw->pw_name, pw->pw_passwd, pw->pw_uid, 390 pw->pw_gid, pw->pw_class, pw->pw_change, 391 pw->pw_expire, pw->pw_gecos, pw->pw_dir, 392 pw->pw_shell); 393 } else { 394 snprintf(pwbuf, sizeof pwbuf, formats[i], 395 pw->pw_name, *(ptr+1) == '*' ? "*" : pw->pw_passwd, 396 pw->pw_uid, pw->pw_gid, pw->pw_gecos, pw->pw_dir, 397 pw->pw_shell); 398 } 399 400 #define FLAGS O_RDWR|O_CREAT 401 402 if ((dbp = yp_open_db_rw(domain, maps[i], FLAGS)) == NULL) { 403 yp_error("couldn't open %s/%s r/w: %s",domain, 404 maps[i],strerror(errno)); 405 return(1); 406 } 407 408 data.data = pwbuf; 409 data.size = strlen(pwbuf); 410 411 if (yp_put_record(dbp, &key, &data, 1) != YP_TRUE) { 412 yp_error("failed to update record in %s/%s", domain, 413 maps[i]); 414 (dbp->close)(dbp); 415 return(1); 416 } 417 418 key.data = yp_last; 419 key.size = strlen(yp_last); 420 data.data = (char *)&yplastbuf; 421 data.size = strlen(yplastbuf); 422 423 if (yp_put_record(dbp, &key, &data, 1) != YP_TRUE) { 424 yp_error("failed to update timestamp in %s/%s", domain, 425 maps[i]); 426 (dbp->close)(dbp); 427 return(1); 428 } 429 430 (dbp->close)(dbp); 431 } 432 433 return(0); 434 } 435 436 int * 437 yppasswdproc_update_1_svc(yppasswd *argp, struct svc_req *rqstp) 438 { 439 static int result; 440 struct sockaddr_in *rqhost; 441 DBT key, data; 442 int rval = 0; 443 int pfd, tfd; 444 int pid; 445 int passwd_changed = 0; 446 int shell_changed = 0; 447 int gecos_changed = 0; 448 char *oldshell = NULL; 449 char *oldgecos = NULL; 450 char *passfile_hold; 451 char passfile_buf[MAXPATHLEN + 2]; 452 char passfile_hold_buf[MAXPATHLEN + 2]; 453 char *domain = yppasswd_domain; 454 static struct sockaddr_in clntaddr; 455 static struct timeval t_saved, t_test; 456 457 /* 458 * Normal user updates always use the 'default' master.passwd file. 459 */ 460 461 passfile = passfile_default; 462 result = 1; 463 464 rqhost = svc_getcaller(rqstp->rq_xprt); 465 466 gettimeofday(&t_test, NULL); 467 if (!bcmp(rqhost, &clntaddr, sizeof *rqhost) && 468 t_test.tv_sec > t_saved.tv_sec && 469 t_test.tv_sec - t_saved.tv_sec < 300) { 470 471 bzero(&clntaddr, sizeof clntaddr); 472 bzero(&t_saved, sizeof t_saved); 473 return(NULL); 474 } 475 476 bcopy(rqhost, &clntaddr, sizeof clntaddr); 477 gettimeofday(&t_saved, NULL); 478 479 if (yp_access(resvport ? "master.passwd.byname" : NULL, rqstp)) { 480 yp_error("rejected update request from unauthorized host"); 481 svcerr_auth(rqstp->rq_xprt, AUTH_BADCRED); 482 return(&result); 483 } 484 485 /* 486 * Step one: find the user. (It's kinda pointless to 487 * proceed if the user doesn't exist.) We look for the 488 * user in the master.passwd.byname database, _NOT_ by 489 * using getpwent() and friends! We can't use getpwent() 490 * since the NIS master server is not guaranteed to be 491 * configured as an NIS client. 492 */ 493 494 if (multidomain) { 495 if ((domain = find_domain(&argp->newpw)) == NULL) { 496 yp_error("multidomain lookup failed - aborting update"); 497 return(&result); 498 } else 499 yp_error("updating user %s in domain %s", 500 argp->newpw.pw_name, domain); 501 } 502 503 key.data = argp->newpw.pw_name; 504 key.size = strlen(argp->newpw.pw_name); 505 506 if ((rval = yp_get_record(domain,"master.passwd.byname", 507 &key, &data, 0)) != YP_TRUE) { 508 if (rval == YP_NOKEY) { 509 yp_error("user %s not found in passwd database", 510 argp->newpw.pw_name); 511 } else { 512 yp_error("database access error: %s", 513 yperr_string(rval)); 514 } 515 return(&result); 516 } 517 518 /* Nul terminate, please. */ 519 *((char *)data.data + data.size) = '\0'; 520 521 copy_yp_pass(data.data, 1, data.size); 522 523 /* Step 2: check that the supplied oldpass is valid. */ 524 525 if (strcmp(crypt(argp->oldpass, yp_password.pw_passwd), 526 yp_password.pw_passwd)) { 527 yp_error("rejected change attempt -- bad password"); 528 yp_error("client address: %s username: %s", 529 inet_ntoa(rqhost->sin_addr), 530 argp->newpw.pw_name); 531 return(&result); 532 } 533 534 /* Step 3: validate the arguments passed to us by the client. */ 535 536 if (validate(&yp_password, &argp->newpw)) { 537 yp_error("rejecting change attempt: bad arguments"); 538 yp_error("client address: %s username: %s", 539 inet_ntoa(rqhost->sin_addr), 540 argp->newpw.pw_name); 541 svcerr_decode(rqstp->rq_xprt); 542 return(&result); 543 } 544 545 /* Step 4: update the user's passwd structure. */ 546 547 if (!no_chsh && strcmp(argp->newpw.pw_shell, yp_password.pw_shell)) { 548 oldshell = yp_password.pw_shell; 549 yp_password.pw_shell = argp->newpw.pw_shell; 550 shell_changed++; 551 } 552 553 554 if (!no_chfn && strcmp(argp->newpw.pw_gecos, yp_password.pw_gecos)) { 555 oldgecos = yp_password.pw_gecos; 556 yp_password.pw_gecos = argp->newpw.pw_gecos; 557 gecos_changed++; 558 } 559 560 if (strcmp(argp->newpw.pw_passwd, yp_password.pw_passwd)) { 561 yp_password.pw_passwd = argp->newpw.pw_passwd; 562 yp_password.pw_change = 0; 563 passwd_changed++; 564 } 565 566 /* 567 * If the caller specified a domain other than our 'default' 568 * domain, change the path to master.passwd accordingly. 569 */ 570 571 if (strcmp(domain, yppasswd_domain)) { 572 snprintf(passfile_buf, sizeof(passfile_buf), 573 "%s/%s/master.passwd", yp_dir, domain); 574 passfile = (char *)&passfile_buf; 575 } 576 577 /* 578 * Create a filename to hold the original master.passwd 579 * so if our call to yppwupdate fails we can roll back 580 */ 581 snprintf(passfile_hold_buf, sizeof(passfile_hold_buf), 582 "%s.hold", passfile); 583 passfile_hold = (char *)&passfile_hold_buf; 584 585 586 /* Step 5: make a new password file with the updated info. */ 587 588 if (pw_init(dirname(passfile), passfile)) { 589 yp_error("pw_init() failed"); 590 return &result; 591 } 592 if ((pfd = pw_lock()) == -1) { 593 pw_fini(); 594 yp_error("pw_lock() failed"); 595 return &result; 596 } 597 if ((tfd = pw_tmp(-1)) == -1) { 598 pw_fini(); 599 yp_error("pw_tmp() failed"); 600 return &result; 601 } 602 if (pw_copy(pfd, tfd, &yp_password, NULL) == -1) { 603 pw_fini(); 604 yp_error("pw_copy() failed"); 605 return &result; 606 } 607 if (rename(passfile, passfile_hold) == -1) { 608 pw_fini(); 609 yp_error("rename of %s to %s failed", passfile, 610 passfile_hold); 611 return &result; 612 } 613 614 if (strcmp(passfile, _PATH_MASTERPASSWD) == 0) { 615 /* 616 * NIS server is exporting the system's master.passwd. 617 * Call pw_mkdb to rebuild passwd and the .db files 618 */ 619 if (pw_mkdb(yp_password.pw_name) == -1) { 620 pw_fini(); 621 yp_error("pw_mkdb() failed"); 622 rename(passfile_hold, passfile); 623 return &result; 624 } 625 } else { 626 /* 627 * NIS server is exporting a private master.passwd. 628 * Rename tempfile into final location 629 */ 630 if (rename(pw_tempname(), passfile) == -1) { 631 pw_fini(); 632 yp_error("rename of %s to %s failed", 633 pw_tempname(), passfile); 634 rename(passfile_hold, passfile); 635 return &result; 636 } 637 } 638 639 pw_fini(); 640 641 if (inplace) { 642 if ((rval = update_inplace(&yp_password, domain))) { 643 yp_error("inplace update failed -- rebuilding maps"); 644 } 645 } 646 647 switch ((pid = fork())) { 648 case 0: 649 if (inplace && !rval) { 650 execlp(MAP_UPDATE_PATH, MAP_UPDATE, passfile, 651 yppasswd_domain, "pushpw", NULL); 652 } else { 653 execlp(MAP_UPDATE_PATH, MAP_UPDATE, passfile, 654 yppasswd_domain, NULL); 655 } 656 yp_error("couldn't exec map update process: %s", 657 strerror(errno)); 658 unlink(passfile); 659 rename(passfile_hold, passfile); 660 exit(1); 661 break; 662 case -1: 663 yp_error("fork() failed: %s", strerror(errno)); 664 unlink(passfile); 665 rename(passfile_hold, passfile); 666 return(&result); 667 break; 668 default: 669 unlink(passfile_hold); 670 break; 671 } 672 673 if (verbose) { 674 yp_error("update completed for user %s (uid %d) in %s:", 675 argp->newpw.pw_name, argp->newpw.pw_uid, passfile); 676 677 if (passwd_changed) 678 yp_error("password changed"); 679 680 if (gecos_changed) 681 yp_error("gecos changed ('%s' -> '%s')", 682 oldgecos, argp->newpw.pw_gecos); 683 684 if (shell_changed) 685 yp_error("shell changed ('%s' -> '%s')", 686 oldshell, argp->newpw.pw_shell); 687 } 688 689 result = 0; 690 return (&result); 691 } 692 693 /* 694 * Note that this function performs a little less sanity checking 695 * than the last one. Since only the superuser is allowed to use it, 696 * it is assumed that the caller knows what he's doing. 697 */ 698 int * 699 yppasswdproc_update_master_1_svc(master_yppasswd *argp, struct svc_req *rqstp) 700 { 701 static int result; 702 int pfd, tfd; 703 int pid; 704 uid_t uid; 705 int rval = 0; 706 DBT key, data; 707 char *passfile_hold; 708 char passfile_buf[MAXPATHLEN + 2]; 709 char passfile_hold_buf[MAXPATHLEN + 2]; 710 struct sockaddr_in *rqhost; 711 SVCXPRT *transp; 712 713 result = 1; 714 transp = rqstp->rq_xprt; 715 716 /* 717 * NO AF_INET CONNETCIONS ALLOWED! 718 */ 719 rqhost = svc_getcaller(transp); 720 if (rqhost->sin_family != AF_UNIX) { 721 yp_error("Alert! %s/%d attempted to use superuser-only \ 722 procedure!\n", inet_ntoa(rqhost->sin_addr), rqhost->sin_port); 723 svcerr_auth(transp, AUTH_BADCRED); 724 return(&result); 725 } 726 727 if (rqstp->rq_cred.oa_flavor != AUTH_SYS) { 728 yp_error("caller didn't send proper credentials"); 729 svcerr_auth(transp, AUTH_BADCRED); 730 return(&result); 731 } 732 733 if (__rpc_get_local_uid(transp, &uid) < 0) { 734 yp_error("caller didn't send proper credentials"); 735 svcerr_auth(transp, AUTH_BADCRED); 736 return(&result); 737 } 738 739 if (uid) { 740 yp_error("caller euid is %d, expecting 0 -- rejecting request", 741 uid); 742 svcerr_auth(rqstp->rq_xprt, AUTH_BADCRED); 743 return(&result); 744 } 745 746 passfile = passfile_default; 747 748 key.data = argp->newpw.pw_name; 749 key.size = strlen(argp->newpw.pw_name); 750 751 /* 752 * The superuser may add entries to the passwd maps if 753 * rpc.yppasswdd is started with the -a flag. Paranoia 754 * prevents me from allowing additions by default. 755 */ 756 if ((rval = yp_get_record(argp->domain, "master.passwd.byname", 757 &key, &data, 0)) != YP_TRUE) { 758 if (rval == YP_NOKEY) { 759 yp_error("user %s not found in passwd database", 760 argp->newpw.pw_name); 761 if (allow_additions) 762 yp_error("notice: adding user %s to \ 763 master.passwd database for domain %s", argp->newpw.pw_name, argp->domain); 764 else 765 yp_error("restart rpc.yppasswdd with the -a flag to \ 766 allow additions to be made to the password database"); 767 } else { 768 yp_error("database access error: %s", 769 yperr_string(rval)); 770 } 771 if (!allow_additions) 772 return(&result); 773 } else { 774 775 /* Nul terminate, please. */ 776 *((char *)data.data + data.size) = '\0'; 777 778 copy_yp_pass(data.data, 1, data.size); 779 } 780 781 /* 782 * Perform a small bit of sanity checking. 783 */ 784 if (validate_master(rval == YP_TRUE ? &yp_password:NULL,&argp->newpw)){ 785 yp_error("rejecting update attempt for %s: bad arguments", 786 argp->newpw.pw_name); 787 return(&result); 788 } 789 790 /* 791 * If the caller specified a domain other than our 'default' 792 * domain, change the path to master.passwd accordingly. 793 */ 794 795 if (strcmp(argp->domain, yppasswd_domain)) { 796 snprintf(passfile_buf, sizeof(passfile_buf), 797 "%s/%s/master.passwd", yp_dir, argp->domain); 798 passfile = (char *)&passfile_buf; 799 } 800 801 /* 802 * Create a filename to hold the original master.passwd 803 * so if our call to yppwupdate fails we can roll back 804 */ 805 snprintf(passfile_hold_buf, sizeof(passfile_hold_buf), 806 "%s.hold", passfile); 807 passfile_hold = (char *)&passfile_hold_buf; 808 809 if (pw_init(dirname(passfile), passfile)) { 810 yp_error("pw_init() failed"); 811 return &result; 812 } 813 if ((pfd = pw_lock()) == -1) { 814 pw_fini(); 815 yp_error("pw_lock() failed"); 816 return &result; 817 } 818 if ((tfd = pw_tmp(-1)) == -1) { 819 pw_fini(); 820 yp_error("pw_tmp() failed"); 821 return &result; 822 } 823 if (pw_copy(pfd, tfd, (struct passwd *)&argp->newpw, NULL) == -1) { 824 pw_fini(); 825 yp_error("pw_copy() failed"); 826 return &result; 827 } 828 if (rename(passfile, passfile_hold) == -1) { 829 pw_fini(); 830 yp_error("rename of %s to %s failed", passfile, 831 passfile_hold); 832 return &result; 833 } 834 if (strcmp(passfile, _PATH_MASTERPASSWD) == 0) { 835 /* 836 * NIS server is exporting the system's master.passwd. 837 * Call pw_mkdb to rebuild passwd and the .db files 838 */ 839 if (pw_mkdb(argp->newpw.pw_name) == -1) { 840 pw_fini(); 841 yp_error("pw_mkdb() failed"); 842 rename(passfile_hold, passfile); 843 return &result; 844 } 845 } else { 846 /* 847 * NIS server is exporting a private master.passwd. 848 * Rename tempfile into final location 849 */ 850 if (rename(pw_tempname(), passfile) == -1) { 851 pw_fini(); 852 yp_error("rename of %s to %s failed", 853 pw_tempname(), passfile); 854 rename(passfile_hold, passfile); 855 return &result; 856 } 857 } 858 pw_fini(); 859 860 if (inplace) { 861 if ((rval = update_inplace((struct passwd *)&argp->newpw, 862 argp->domain))) { 863 yp_error("inplace update failed -- rebuilding maps"); 864 } 865 } 866 867 switch ((pid = fork())) { 868 case 0: 869 if (inplace && !rval) { 870 execlp(MAP_UPDATE_PATH, MAP_UPDATE, passfile, 871 argp->domain, "pushpw", NULL); 872 } else { 873 execlp(MAP_UPDATE_PATH, MAP_UPDATE, passfile, 874 argp->domain, NULL); 875 } 876 yp_error("couldn't exec map update process: %s", 877 strerror(errno)); 878 unlink(passfile); 879 rename(passfile_hold, passfile); 880 exit(1); 881 break; 882 case -1: 883 yp_error("fork() failed: %s", strerror(errno)); 884 unlink(passfile); 885 rename(passfile_hold, passfile); 886 return(&result); 887 break; 888 default: 889 unlink(passfile_hold); 890 break; 891 } 892 893 yp_error("performed update of user %s (uid %d) domain %s", 894 argp->newpw.pw_name, 895 argp->newpw.pw_uid, 896 argp->domain); 897 898 result = 0; 899 return(&result); 900 } 901