misc/uuidd.c

   1 /*
   2  * uuidd.c --- UUID-generation daemon
   3  *
   4  * Copyright (C) 2007  Theodore Ts'o
   5  *
   6  * %Begin-Header%
   7  * This file may be redistributed under the terms of the GNU Public
   8  * License.
   9  * %End-Header%
  10  */
  11
  12 #define _GNU_SOURCE /* for setres[ug]id() */
  13
  14 #include <stdio.h>
  15 #ifdef HAVE_STDLIB_H
  16 #include <stdlib.h>
  17 #endif
  18 #include <unistd.h>
  19 #include <inttypes.h>
  20 #include <errno.h>
  21 #include <sys/types.h>
  22 #include <sys/stat.h>
  23 #include <sys/socket.h>
  24 #include <sys/un.h>
  25 #include <fcntl.h>
  26 #include <signal.h>
  27 #include <string.h>
  28 #ifdef HAVE_GETOPT_H
  29 #include <getopt.h>
  30 #else
  31 extern int getopt(int argc, char * const argv[], const char *optstring);
  32 extern char *optarg;
  33 extern int optind;
  34 #endif
  35 #include "uuid/uuid.h"
  36 #include "uuid/uuidd.h"
  37 #include "nls-enable.h"
  38
  39 #ifdef __GNUC__
  40 #define CODE_ATTR(x) __attribute__(x)
  41 #else
  42 #define CODE_ATTR(x)
  43 #endif
  44
  45 static void usage(const char *progname)
  46 {
  47         fprintf(stderr, _("Usage: %s [-d] [-p pidfile] [-s socketpath] "
  48                           "[-T timeout]\n"), progname);
  49         fprintf(stderr, _("       %s [-r|t] [-n num] [-s socketpath]\n"),
  50                 progname);
  51         fprintf(stderr, _("       %s -k\n"), progname);
  52         exit(1);
  53 }
  54
  55 static void die(const char *msg)
  56 {
  57         perror(msg);
  58         exit(1);
  59 }
  60
  61 static void create_daemon(void)
  62 {
  63         pid_t pid;
  64         uid_t euid;
  65
  66         pid = fork();
  67         if (pid == -1) {
  68                 perror("fork");
  69                 exit(1);
  70         } else if (pid != 0) {
  71             exit(0);
  72         }
  73
  74         close(0);
  75         close(1);
  76         close(2);
  77         open("/dev/null", O_RDWR);
  78         open("/dev/null", O_RDWR);
  79         open("/dev/null", O_RDWR);
  80
  81         chdir("/");
  82         (void) setsid();
  83         euid = geteuid();
  84         if (setreuid(euid, euid) < 0)
  85                 die("setreuid");
  86 }
  87
  88 static int read_all(int fd, char *buf, size_t count)
  89 {
  90         ssize_t ret;
  91         int c = 0;
  92
  93         memset(buf, 0, count);
  94         while (count > 0) {
  95                 ret = read(fd, buf, count);
  96                 if (ret < 0) {
  97                         if ((errno == EAGAIN) || (errno == EINTR))
  98                                 continue;
  99                         return -1;
 100                 }
 101                 count -= ret;
 102                 buf += ret;
 103                 c += ret;
 104         }
 105         return c;
 106 }
 107
 108 static const char *cleanup_pidfile, *cleanup_socket;
 109
 110 static void terminate_intr(int signo CODE_ATTR((unused)))
 111 {
 112         (void) unlink(cleanup_pidfile);
 113         if (cleanup_socket)
 114                 (void) unlink(cleanup_socket);
 115         exit(0);
 116 }
 117
 118 static int call_daemon(const char *socket_path, int op, char *buf,
 119                        int buflen, int *num, const char **err_context)
 120 {
 121         char op_buf[8];
 122         int op_len;
 123         int s;
 124         ssize_t ret;
 125         int32_t reply_len = 0;
 126         struct sockaddr_un srv_addr;
 127
 128         if (((op == 4) || (op == 5)) && !num) {
 129                 if (err_context)
 130                         *err_context = _("bad arguments");
 131                 errno = EINVAL;
 132                 return -1;
 133         }
 134
 135         if ((s = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
 136                 if (err_context)
 137                         *err_context = _("socket");
 138                 return -1;
 139         }
 140
 141         srv_addr.sun_family = AF_UNIX;
 142         strncpy(srv_addr.sun_path, socket_path, sizeof(srv_addr.sun_path));
 143         srv_addr.sun_path[sizeof(srv_addr.sun_path)-1] = '\0';
 144
 145         if (connect(s, (const struct sockaddr *) &srv_addr,
 146                     sizeof(struct sockaddr_un)) < 0) {
 147                 if (err_context)
 148                         *err_context = _("connect");
 149                 close(s);
 150                 return -1;
 151         }
 152
 153         if (op == 5) {
 154                 if ((*num)*16 > buflen-4)
 155                         *num = (buflen-4) / 16;
 156         }
 157         op_buf[0] = op;
 158         op_len = 1;
 159         if ((op == 4) || (op == 5)) {
 160                 memcpy(op_buf+1, num, sizeof(int));
 161                 op_len += sizeof(int);
 162         }
 163
 164         ret = write(s, op_buf, op_len);
 165         if (ret < op_len) {
 166                 if (err_context)
 167                         *err_context = _("write");
 168                 close(s);
 169                 return -1;
 170         }
 171
 172         ret = read_all(s, (char *) &reply_len, sizeof(reply_len));
 173         if (ret < 0) {
 174                 if (err_context)
 175                         *err_context = _("read count");
 176                 close(s);
 177                 return -1;
 178         }
 179         if (reply_len < 0 || reply_len > buflen) {
 180                 if (err_context)
 181                         *err_context = _("bad response length");
 182                 close(s);
 183                 return -1;
 184         }
 185         ret = read_all(s, (char *) buf, reply_len);
 186
 187         if ((ret > 0) && (op == 4)) {
 188                 if (reply_len >= (int) (16+sizeof(int)))
 189                         memcpy(buf+16, num, sizeof(int));
 190                 else
 191                         *num = -1;
 192         }
 193         if ((ret > 0) && (op == 5)) {
 194                 if (*num >= (int) sizeof(int))
 195                         memcpy(buf, num, sizeof(int));
 196                 else
 197                         *num = -1;
 198         }
 199
 200         close(s);
 201
 202         return ret;
 203 }
 204
 205 static void server_loop(const char *socket_path, const char *pidfile_path,
 206                         int debug, int timeout, int quiet)
 207 {
 208         struct sockaddr_un      my_addr, from_addr;
 209         struct flock            fl;
 210         socklen_t               fromlen;
 211         int32_t                 reply_len = 0;
 212         uuid_t                  uu;
 213         mode_t                  save_umask;
 214         char                    reply_buf[1024], *cp;
 215         char                    op, str[37];
 216         int                     i, s, ns, len, num;
 217         int                     fd_pidfile, ret;
 218
 219         fd_pidfile = open(pidfile_path, O_CREAT | O_RDWR, 0664);
 220         if (fd_pidfile < 0) {
 221                 if (!quiet)
 222                         fprintf(stderr, "Failed to open/create %s: %s\n",
 223                                 pidfile_path, strerror(errno));
 224                 exit(1);
 225         }
 226         cleanup_pidfile = pidfile_path;
 227         cleanup_socket = 0;
 228         signal(SIGALRM, terminate_intr);
 229         alarm(30);
 230         fl.l_type = F_WRLCK;
 231         fl.l_whence = SEEK_SET;
 232         fl.l_start = 0;
 233         fl.l_len = 0;
 234         fl.l_pid = 0;
 235         while (fcntl(fd_pidfile, F_SETLKW, &fl) < 0) {
 236                 if ((errno == EAGAIN) || (errno == EINTR))
 237                         continue;
 238                 if (!quiet)
 239                         fprintf(stderr, "Failed to lock %s: %s\n",
 240                                 pidfile_path, strerror(errno));
 241                 exit(1);
 242         }
 243         ret = call_daemon(socket_path, 0, reply_buf, sizeof(reply_buf), 0, 0);
 244         if (ret > 0) {
 245                 if (!quiet)
 246                         printf(_("uuidd daemon already running at pid %s\n"),
 247                                reply_buf);
 248                 exit(1);
 249         }
 250         alarm(0);
 251
 252         if ((s = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
 253                 if (!quiet)
 254                         fprintf(stderr, _("Couldn't create unix stream "
 255                                           "socket: %s"), strerror(errno));
 256                 exit(1);
 257         }
 258
 259         /*
 260          * Create the address we will be binding to.
 261          */
 262         my_addr.sun_family = AF_UNIX;
 263         strncpy(my_addr.sun_path, socket_path, sizeof(my_addr.sun_path));
 264         my_addr.sun_path[sizeof(my_addr.sun_path)-1] = '\0';
 265         (void) unlink(socket_path);
 266         save_umask = umask(0);
 267         if (bind(s, (const struct sockaddr *) &my_addr,
 268                  sizeof(struct sockaddr_un)) < 0) {
 269                 if (!quiet)
 270                         fprintf(stderr,
 271                                 _("Couldn't bind unix socket %s: %s\n"),
 272                                 socket_path, strerror(errno));
 273                 exit(1);
 274         }
 275         (void) umask(save_umask);
 276
 277         if (listen(s, 5) < 0) {
 278                 if (!quiet)
 279                         fprintf(stderr, _("Couldn't listen on unix "
 280                                           "socket %s: %s\n"), socket_path,
 281                                 strerror(errno));
 282                 exit(1);
 283         }
 284
 285         cleanup_socket = socket_path;
 286         if (!debug)
 287                 create_daemon();
 288         signal(SIGHUP, terminate_intr);
 289         signal(SIGINT, terminate_intr);
 290         signal(SIGTERM, terminate_intr);
 291         signal(SIGALRM, terminate_intr);
 292         signal(SIGPIPE, SIG_IGN);
 293
 294         sprintf(reply_buf, "%d\n", getpid());
 295         ftruncate(fd_pidfile, 0);
 296         write(fd_pidfile, reply_buf, strlen(reply_buf));
 297         if (fd_pidfile > 1)
 298                 close(fd_pidfile); /* Unlock the pid file */
 299
 300         while (1) {
 301                 fromlen = sizeof(from_addr);
 302                 if (timeout > 0)
 303                         alarm(timeout);
 304                 ns = accept(s, (struct sockaddr *) &from_addr, &fromlen);
 305                 alarm(0);
 306                 if (ns < 0) {
 307                         if ((errno == EAGAIN) || (errno == EINTR))
 308                                 continue;
 309                         perror("accept");
 310                         exit(1);
 311                 }
 312                 len = read(ns, &op, 1);
 313                 if (len != 1) {
 314                         if (len < 0)
 315                                 perror("read");
 316                         else
 317                                 printf(_("Error reading from client, "
 318                                          "len = %d\n"), len);
 319                         goto shutdown_socket;
 320                 }
 321                 if ((op == 4) || (op == 5)) {
 322                         if (read_all(ns, (char *) &num, sizeof(num)) != 4)
 323                                 goto shutdown_socket;
 324                         if (debug)
 325                                 printf(_("operation %d, incoming num = %d\n"),
 326                                        op, num);
 327                 } else if (debug)
 328                         printf("operation %d\n", op);
 329
 330                 switch(op) {
 331                 case UUIDD_OP_GETPID:
 332                         sprintf(reply_buf, "%d", getpid());
 333                         reply_len = strlen(reply_buf)+1;
 334                         break;
 335                 case UUIDD_OP_GET_MAXOP:
 336                         sprintf(reply_buf, "%d", UUIDD_MAX_OP);
 337                         reply_len = strlen(reply_buf)+1;
 338                         break;
 339                 case UUIDD_OP_TIME_UUID:
 340                         num = 1;
 341                         uuid__generate_time(uu, &num);
 342                         if (debug) {
 343                                 uuid_unparse(uu, str);
 344                                 printf(_("Generated time UUID: %s\n"), str);
 345                         }
 346                         memcpy(reply_buf, uu, sizeof(uu));
 347                         reply_len = sizeof(uu);
 348                         break;
 349                 case UUIDD_OP_RANDOM_UUID:
 350                         num = 1;
 351                         uuid__generate_random(uu, &num);
 352                         if (debug) {
 353                                 uuid_unparse(uu, str);
 354                                 printf(_("Generated random UUID: %s\n"), str);
 355                         }
 356                         memcpy(reply_buf, uu, sizeof(uu));
 357                         reply_len = sizeof(uu);
 358                         break;
 359                 case UUIDD_OP_BULK_TIME_UUID:
 360                         uuid__generate_time(uu, &num);
 361                         if (debug) {
 362                                 uuid_unparse(uu, str);
 363                                 printf(_("Generated time UUID %s and %d "
 364                                          "following\n"), str, num);
 365                         }
 366                         memcpy(reply_buf, uu, sizeof(uu));
 367                         reply_len = sizeof(uu);
 368                         memcpy(reply_buf+reply_len, &num, sizeof(num));
 369                         reply_len += sizeof(num);
 370                         break;
 371                 case UUIDD_OP_BULK_RANDOM_UUID:
 372                         if (num < 0)
 373                                 num = 1;
 374                         if (num > 1000)
 375                                 num = 1000;
 376                         if (num*16 > (int) (sizeof(reply_buf)-sizeof(num)))
 377                                 num = (sizeof(reply_buf)-sizeof(num)) / 16;
 378                         uuid__generate_random((unsigned char *) reply_buf +
 379                                               sizeof(num), &num);
 380                         if (debug) {
 381                                 printf(_("Generated %d UUID's:\n"), num);
 382                                 for (i=0, cp=reply_buf+sizeof(num);
 383                                      i < num; i++, cp+=16) {
 384                                         uuid_unparse((unsigned char *)cp, str);
 385                                         printf("\t%s\n", str);
 386                                 }
 387                         }
 388                         reply_len = (num*16) + sizeof(num);
 389                         memcpy(reply_buf, &num, sizeof(num));
 390                         break;
 391                 default:
 392                         if (debug)
 393                                 printf(_("Invalid operation %d\n"), op);
 394                         goto shutdown_socket;
 395                 }
 396                 write(ns, &reply_len, sizeof(reply_len));
 397                 write(ns, reply_buf, reply_len);
 398         shutdown_socket:
 399                 close(ns);
 400         }
 401 }
 402
 403 int main(int argc, char **argv)
 404 {
 405         const char      *socket_path = UUIDD_SOCKET_PATH;
 406         const char      *pidfile_path = UUIDD_PIDFILE_PATH;
 407         const char      *err_context;
 408         char            buf[1024], *cp;
 409         char            str[37], *tmp;
 410         uuid_t          uu;
 411         uid_t           uid;
 412         gid_t           gid;
 413         int             i, c, ret;
 414         int             debug = 0, do_type = 0, do_kill = 0, num = 0;
 415         int             timeout = 0, quiet = 0, drop_privs = 0;
 416
 417 #ifdef ENABLE_NLS
 418         setlocale(LC_MESSAGES, "");
 419         setlocale(LC_CTYPE, "");
 420         bindtextdomain(NLS_CAT_NAME, LOCALEDIR);
 421         textdomain(NLS_CAT_NAME);
 422 #endif
 423
 424         while ((c = getopt (argc, argv, "dkn:qp:s:tT:r")) != EOF) {
 425                 switch (c) {
 426                 case 'd':
 427                         debug++;
 428                         drop_privs = 1;
 429                         break;
 430                 case 'k':
 431                         do_kill++;
 432                         drop_privs = 1;
 433                         break;
 434                 case 'n':
 435                         num = strtol(optarg, &tmp, 0);
 436                         if ((num < 0) || *tmp) {
 437                                 fprintf(stderr, _("Bad number: %s\n"), optarg);
 438                                 exit(1);
 439                         }
 440                 case 'p':
 441                         pidfile_path = optarg;
 442                         drop_privs = 1;
 443                         break;
 444                 case 'q':
 445                         quiet++;
 446                         break;
 447                 case 's':
 448                         socket_path = optarg;
 449                         drop_privs = 1;
 450                         break;
 451                 case 't':
 452                         do_type = UUIDD_OP_TIME_UUID;
 453                         drop_privs = 1;
 454                         break;
 455                 case 'T':
 456                         timeout = strtol(optarg, &tmp, 0);
 457                         if ((timeout < 0) || *tmp) {
 458                                 fprintf(stderr, _("Bad number: %s\n"), optarg);
 459                                 exit(1);
 460                         }
 461                         break;
 462                 case 'r':
 463                         do_type = UUIDD_OP_RANDOM_UUID;
 464                         drop_privs = 1;
 465                         break;
 466                 default:
 467                         usage(argv[0]);
 468                 }
 469         }
 470         uid = getuid();
 471         if (uid && drop_privs) {
 472                 gid = getgid();
 473 #ifdef HAVE_SETRESGID
 474                 if (setresgid(gid, gid, gid) < 0)
 475                         die("setresgid");
 476 #else
 477                 if (setregid(gid, gid) < 0)
 478                         die("setregid");
 479 #endif
 480
 481 #ifdef HAVE_SETRESUID
 482                 if (setresuid(uid, uid, uid) < 0)
 483                         die("setresuid");
 484 #else
 485                 if (setreuid(uid, uid) < 0)
 486                         die("setreuid");
 487 #endif
 488         }
 489         if (num && do_type) {
 490                 ret = call_daemon(socket_path, do_type+2, buf,
 491                                   sizeof(buf), &num, &err_context);
 492                 if (ret < 0) {
 493                         printf(_("Error calling uuidd daemon (%s): %s\n"),
 494                                err_context, strerror(errno));
 495                         exit(1);
 496                 }
 497                 if (do_type == UUIDD_OP_TIME_UUID) {
 498                         if (ret != sizeof(uu) + sizeof(num))
 499                                 goto unexpected_size;
 500
 501                         uuid_unparse((unsigned char *) buf, str);
 502
 503                         printf(_("%s and subsequent %d UUID's\n"), str, num);
 504                 } else {
 505                         printf(_("List of UUID's:\n"));
 506                         cp = buf + 4;
 507                         if (ret != (int) (sizeof(num) + num*sizeof(uu)))
 508                                 goto unexpected_size;
 509                         for (i=0; i < num; i++, cp+=16) {
 510                                 uuid_unparse((unsigned char *) cp, str);
 511                                 printf("\t%s\n", str);
 512                         }
 513                 }
 514                 exit(0);
 515         }
 516         if (do_type) {
 517                 ret = call_daemon(socket_path, do_type, (char *) &uu,
 518                                   sizeof(uu), 0, &err_context);
 519                 if (ret < 0) {
 520                         printf(_("Error calling uuidd daemon (%s): %s\n"),
 521                                err_context, strerror(errno));
 522                         exit(1);
 523                 }
 524                 if (ret != sizeof(uu)) {
 525                 unexpected_size:
 526                         printf(_("Unexpected reply length from server %d\n"),
 527                                ret);
 528                         exit(1);
 529                 }
 530                 uuid_unparse(uu, str);
 531
 532                 printf("%s\n", str);
 533                 exit(0);
 534         }
 535
 536         if (do_kill) {
 537                 ret = call_daemon(socket_path, 0, buf, sizeof(buf), 0, 0);
 538                 if ((ret > 0) && ((do_kill = atoi((char *) buf)) > 0)) {
 539                         ret = kill(do_kill, SIGTERM);
 540                         if (ret < 0) {
 541                                 if (!quiet)
 542                                         fprintf(stderr,
 543                                                 _("Couldn't kill uuidd running "
 544                                                   "at pid %d: %s\n"), do_kill,
 545                                                 strerror(errno));
 546                                 exit(1);
 547                         }
 548                         if (!quiet)
 549                                 printf(_("Killed uuidd running at pid %d\n"),
 550                                        do_kill);
 551                 }
 552                 exit(0);
 553         }
 554
 555         server_loop(socket_path, pidfile_path, debug, timeout, quiet);
 556         return 0;
 557 }