scheduler/process.c

   1 /*
   2  * Process management routines for the CUPS scheduler.
   3  *
   4  * Copyright 2007-2015 by Apple Inc.
   5  * Copyright 1997-2007 by Easy Software Products, all rights reserved.
   6  *
   7  * These coded instructions, statements, and computer programs are the
   8  * property of Apple Inc. and are protected by Federal copyright
   9  * law.  Distribution and use rights are outlined in the file "LICENSE.txt"
  10  * which should have been included with this file.  If this file is
  11  * missing or damaged, see the license at "http://www.cups.org/".
  12  */
  13
  14 /*
  15  * Include necessary headers...
  16  */
  17
  18 #include "cupsd.h"
  19 #include <grp.h>
  20 #ifdef __APPLE__
  21 #  include <libgen.h>
  22 #endif /* __APPLE__ */
  23 #ifdef HAVE_POSIX_SPAWN
  24 #  include <spawn.h>
  25 extern char **environ;
  26 #endif /* HAVE_POSIX_SPAWN */
  27 #ifdef HAVE_POSIX_SPAWN
  28 #  if !defined(__OpenBSD__) || OpenBSD >= 201505
  29 #    define USE_POSIX_SPAWN 1
  30 #  else
  31 #    define USE_POSIX_SPAWN 0
  32 #  endif /* !__OpenBSD__ || */
  33 #else
  34 #  define USE_POSIX_SPAWN 0
  35 #endif /* HAVE_POSIX_SPAWN */
  36
  37
  38 /*
  39  * Process structure...
  40  */
  41
  42 typedef struct
  43 {
  44   int   pid,                            /* Process ID */
  45         job_id;                         /* Job associated with process */
  46   char  name[1];                        /* Name of process */
  47 } cupsd_proc_t;
  48
  49
  50 /*
  51  * Local globals...
  52  */
  53
  54 static cups_array_t     *process_array = NULL;
  55
  56
  57 /*
  58  * Local functions...
  59  */
  60
  61 static int      compare_procs(cupsd_proc_t *a, cupsd_proc_t *b);
  62 #ifdef HAVE_SANDBOX_H
  63 static char     *cupsd_requote(char *dst, const char *src, size_t dstsize);
  64 #endif /* HAVE_SANDBOX_H */
  65
  66
  67 /*
  68  * 'cupsdCreateProfile()' - Create an execution profile for a subprocess.
  69  */
  70
  71 void *                                  /* O - Profile or NULL on error */
  72 cupsdCreateProfile(int job_id,          /* I - Job ID or 0 for none */
  73                    int allow_networking)/* I - Allow networking off machine? */
  74 {
  75 #ifdef HAVE_SANDBOX_H
  76   cups_file_t           *fp;            /* File pointer */
  77   char                  profile[1024],  /* File containing the profile */
  78                         bin[1024],      /* Quoted ServerBin */
  79                         cache[1024],    /* Quoted CacheDir */
  80                         domain[1024],   /* Domain socket, if any */
  81                         request[1024],  /* Quoted RequestRoot */
  82                         root[1024],     /* Quoted ServerRoot */
  83                         state[1024],    /* Quoted StateDir */
  84                         temp[1024];     /* Quoted TempDir */
  85   const char            *nodebug;       /* " (with no-log)" for no debug */
  86   cupsd_listener_t      *lis;           /* Current listening socket */
  87
  88
  89   if (!UseSandboxing || Sandboxing == CUPSD_SANDBOXING_OFF)
  90   {
  91    /*
  92     * Only use sandbox profiles as root...
  93     */
  94
  95     cupsdLogMessage(CUPSD_LOG_DEBUG2, "cupsdCreateProfile(job_id=%d, allow_networking=%d) = NULL", job_id, allow_networking);
  96
  97     return (NULL);
  98   }
  99
 100   if ((fp = cupsTempFile2(profile, sizeof(profile))) == NULL)
 101   {
 102     cupsdLogMessage(CUPSD_LOG_DEBUG2, "cupsdCreateProfile(job_id=%d, allow_networking=%d) = NULL", job_id, allow_networking);
 103     cupsdLogMessage(CUPSD_LOG_ERROR, "Unable to create security profile: %s",
 104                     strerror(errno));
 105     return (NULL);
 106   }
 107
 108   fchown(cupsFileNumber(fp), RunUser, Group);
 109   fchmod(cupsFileNumber(fp), 0640);
 110
 111   cupsd_requote(bin, ServerBin, sizeof(bin));
 112   cupsd_requote(cache, CacheDir, sizeof(cache));
 113   cupsd_requote(request, RequestRoot, sizeof(request));
 114   cupsd_requote(root, ServerRoot, sizeof(root));
 115   cupsd_requote(state, StateDir, sizeof(state));
 116   cupsd_requote(temp, TempDir, sizeof(temp));
 117
 118   nodebug = LogLevel < CUPSD_LOG_DEBUG ? " (with no-log)" : "";
 119
 120   cupsFilePuts(fp, "(version 1)\n");
 121   if (Sandboxing == CUPSD_SANDBOXING_STRICT)
 122     cupsFilePuts(fp, "(deny default)\n");
 123   else
 124     cupsFilePuts(fp, "(allow default)\n");
 125   if (LogLevel >= CUPSD_LOG_DEBUG)
 126     cupsFilePuts(fp, "(debug deny)\n");
 127   cupsFilePuts(fp, "(import \"system.sb\")\n");
 128   cupsFilePuts(fp, "(system-network)\n");
 129   cupsFilePuts(fp, "(allow mach-per-user-lookup)\n");
 130   cupsFilePuts(fp, "(allow ipc-posix-sem)\n");
 131   cupsFilePuts(fp, "(allow ipc-posix-shm)\n");
 132   cupsFilePuts(fp, "(allow ipc-sysv-shm)\n");
 133   cupsFilePuts(fp, "(allow mach-lookup)\n");
 134   if (!RunUser)
 135     cupsFilePrintf(fp,
 136                    "(deny file-write* file-read-data file-read-metadata\n"
 137                    "  (regex"
 138                    " #\"^/Users$\""
 139                    " #\"^/Users/\""
 140                    ")%s)\n", nodebug);
 141   cupsFilePrintf(fp,
 142                  "(deny file-write*\n"
 143                  "  (regex"
 144                  " #\"^%s$\""           /* ServerRoot */
 145                  " #\"^%s/\""           /* ServerRoot/... */
 146                  " #\"^/private/etc$\""
 147                  " #\"^/private/etc/\""
 148                  " #\"^/usr/local/etc$\""
 149                  " #\"^/usr/local/etc/\""
 150                  " #\"^/Library$\""
 151                  " #\"^/Library/\""
 152                  " #\"^/System$\""
 153                  " #\"^/System/\""
 154                  ")%s)\n",
 155                  root, root, nodebug);
 156   /* Specifically allow applications to stat RequestRoot and some other system folders */
 157   cupsFilePrintf(fp,
 158                  "(allow file-read-metadata\n"
 159                  "  (regex"
 160                  " #\"^/$\""            /* / */
 161                  " #\"^/usr$\""         /* /usr */
 162                  " #\"^/Library$\""     /* /Library */
 163                  " #\"^/Library/Printers$\""    /* /Library/Printers */
 164                  " #\"^%s$\""           /* RequestRoot */
 165                  "))\n",
 166                  request);
 167   /* Read and write TempDir, CacheDir, and other common folders */
 168   cupsFilePuts(fp,
 169                "(allow file-write* file-read-data file-read-metadata\n"
 170                "  (regex"
 171                " #\"^/private/var/db/\""
 172                " #\"^/private/var/folders/\""
 173                " #\"^/private/var/lib/\""
 174                " #\"^/private/var/log/\""
 175                " #\"^/private/var/mysql/\""
 176                " #\"^/private/var/run/\""
 177                " #\"^/private/var/spool/\""
 178                " #\"^/Library/Application Support/\""
 179                " #\"^/Library/Caches/\""
 180                " #\"^/Library/Logs/\""
 181                " #\"^/Library/Preferences/\""
 182                " #\"^/Library/WebServer/\""
 183                " #\"^/Users/Shared/\""
 184                "))\n");
 185   cupsFilePrintf(fp,
 186                  "(deny file-write*\n"
 187                  "       (regex #\"^%s$\")%s)\n",
 188                  request, nodebug);
 189   cupsFilePrintf(fp,
 190                  "(deny file-write* file-read-data file-read-metadata\n"
 191                  "       (regex #\"^%s/\")%s)\n",
 192                  request, nodebug);
 193   cupsFilePrintf(fp,
 194                  "(allow file-write* file-read-data file-read-metadata\n"
 195                  "  (regex"
 196                  " #\"^%s$\""           /* TempDir */
 197                  " #\"^%s/\""           /* TempDir/... */
 198                  " #\"^%s$\""           /* CacheDir */
 199                  " #\"^%s/\""           /* CacheDir/... */
 200                  " #\"^%s$\""           /* StateDir */
 201                  " #\"^%s/\""           /* StateDir/... */
 202                  "))\n",
 203                  temp, temp, cache, cache, state, state);
 204   /* Read common folders */
 205   cupsFilePrintf(fp,
 206                  "(allow file-read-data file-read-metadata\n"
 207                  "  (regex"
 208                  " #\"^/AppleInternal$\""
 209                  " #\"^/AppleInternal/\""
 210                  " #\"^/bin$\""         /* /bin */
 211                  " #\"^/bin/\""         /* /bin/... */
 212                  " #\"^/private$\""
 213                  " #\"^/private/etc$\""
 214                  " #\"^/private/etc/\""
 215                  " #\"^/private/tmp$\""
 216                  " #\"^/private/tmp/\""
 217                  " #\"^/private/var$\""
 218                  " #\"^/private/var/db$\""
 219                  " #\"^/private/var/folders$\""
 220                  " #\"^/private/var/lib$\""
 221                  " #\"^/private/var/log$\""
 222                  " #\"^/private/var/mysql$\""
 223                  " #\"^/private/var/run$\""
 224                  " #\"^/private/var/spool$\""
 225                  " #\"^/private/var/tmp$\""
 226                  " #\"^/private/var/tmp/\""
 227                  " #\"^/usr/bin$\""     /* /usr/bin */
 228                  " #\"^/usr/bin/\""     /* /usr/bin/... */
 229                  " #\"^/usr/libexec/cups$\""    /* /usr/libexec/cups */
 230                  " #\"^/usr/libexec/cups/\""    /* /usr/libexec/cups/... */
 231                  " #\"^/usr/libexec/fax$\""     /* /usr/libexec/fax */
 232                  " #\"^/usr/libexec/fax/\""     /* /usr/libexec/fax/... */
 233                  " #\"^/usr/sbin$\""    /* /usr/sbin */
 234                  " #\"^/usr/sbin/\""    /* /usr/sbin/... */
 235                  " #\"^/Library$\""     /* /Library */
 236                  " #\"^/Library/\""     /* /Library/... */
 237                  " #\"^/System$\""      /* /System */
 238                  " #\"^/System/\""      /* /System/... */
 239                  " #\"^%s/Library$\""   /* RequestRoot/Library */
 240                  " #\"^%s/Library/\""   /* RequestRoot/Library/... */
 241                  " #\"^%s$\""           /* ServerBin */
 242                  " #\"^%s/\""           /* ServerBin/... */
 243                  " #\"^%s$\""           /* ServerRoot */
 244                  " #\"^%s/\""           /* ServerRoot/... */
 245                  "))\n",
 246                  request, request, bin, bin, root, root);
 247   if (Sandboxing == CUPSD_SANDBOXING_RELAXED)
 248   {
 249     /* Limited write access to /Library/Printers/... */
 250     cupsFilePuts(fp,
 251                  "(allow file-write*\n"
 252                  "  (regex"
 253                  " #\"^/Library/Printers/.*/\""
 254                  "))\n");
 255     cupsFilePrintf(fp,
 256                    "(deny file-write*\n"
 257                    "  (regex"
 258                    " #\"^/Library/Printers/PPDs$\""
 259                    " #\"^/Library/Printers/PPDs/\""
 260                    " #\"^/Library/Printers/PPD Plugins$\""
 261                    " #\"^/Library/Printers/PPD Plugins/\""
 262                    ")%s)\n", nodebug);
 263   }
 264   /* Allow execution of child processes as long as the programs are not in a user directory */
 265   cupsFilePuts(fp, "(allow process*)\n");
 266   cupsFilePuts(fp, "(deny process-exec (regex #\"^/Users/\"))\n");
 267   if (RunUser && getenv("CUPS_TESTROOT"))
 268   {
 269     /* Allow source directory access in "make test" environment */
 270     char        testroot[1024];         /* Root directory of test files */
 271
 272     cupsd_requote(testroot, getenv("CUPS_TESTROOT"), sizeof(testroot));
 273
 274     cupsFilePrintf(fp,
 275                    "(allow file-write* file-read-data file-read-metadata\n"
 276                    "  (regex"
 277                    " #\"^%s$\""         /* CUPS_TESTROOT */
 278                    " #\"^%s/\""         /* CUPS_TESTROOT/... */
 279                    "))\n",
 280                    testroot, testroot);
 281     cupsFilePrintf(fp,
 282                    "(allow process-exec\n"
 283                    "  (regex"
 284                    " #\"^%s/\""         /* CUPS_TESTROOT/... */
 285                    "))\n",
 286                    testroot);
 287     cupsFilePrintf(fp, "(allow sysctl*)\n");
 288   }
 289   if (job_id)
 290   {
 291     /* Allow job filters to read the current job files... */
 292     cupsFilePrintf(fp,
 293                    "(allow file-read-data file-read-metadata\n"
 294                    "       (regex #\"^%s/([ac]%05d|d%05d-[0-9][0-9][0-9])$\"))\n",
 295                    request, job_id, job_id);
 296   }
 297   else
 298   {
 299     /* Allow email notifications from notifiers... */
 300     cupsFilePuts(fp,
 301                  "(allow process-exec\n"
 302                  "  (literal \"/usr/sbin/sendmail\")\n"
 303                  "  (with no-sandbox))\n");
 304   }
 305   /* Allow access to Bluetooth, USB, and notify_post. */
 306   cupsFilePuts(fp, "(allow iokit*)\n");
 307   cupsFilePuts(fp, "(allow distributed-notification-post)\n");
 308   /* Allow outbound networking to local services */
 309   cupsFilePuts(fp, "(allow network-outbound"
 310                    "\n       (regex #\"^/private/var/run/\" #\"^/private/tmp/\" #\"^/private/var/tmp/\")");
 311   for (lis = (cupsd_listener_t *)cupsArrayFirst(Listeners);
 312        lis;
 313        lis = (cupsd_listener_t *)cupsArrayNext(Listeners))
 314   {
 315     if (httpAddrFamily(&(lis->address)) == AF_LOCAL)
 316     {
 317       httpAddrString(&(lis->address), domain, sizeof(domain));
 318       cupsFilePrintf(fp, "\n       (literal \"%s\")", domain);
 319     }
 320   }
 321   if (allow_networking)
 322   {
 323     /* Allow TCP and UDP networking off the machine... */
 324     cupsFilePuts(fp, "\n       (remote tcp))\n");
 325     cupsFilePuts(fp, "(allow network-bind)\n"); /* for LPD resvport */
 326     cupsFilePuts(fp, "(allow network*\n"
 327                      "       (local udp \"*:*\")\n"
 328                      "       (remote udp \"*:*\"))\n");
 329
 330     /* Also allow access to device files... */
 331     cupsFilePuts(fp, "(allow file-write* file-read-data file-read-metadata file-ioctl\n"
 332                      "       (regex #\"^/dev/\"))\n");
 333
 334     /* And allow kernel extensions to be loaded, e.g., SMB */
 335     cupsFilePuts(fp, "(allow system-kext-load)\n");
 336   }
 337   else
 338   {
 339     /* Only allow SNMP (UDP) and LPD (TCP) off the machine... */
 340     cupsFilePuts(fp, ")\n");
 341     cupsFilePuts(fp, "(allow network-outbound\n"
 342                      "       (remote udp \"*:161\")\n"
 343                      "       (remote tcp \"*:515\"))\n");
 344     cupsFilePuts(fp, "(allow network-inbound\n"
 345                      "       (local udp \"localhost:*\"))\n");
 346   }
 347   cupsFileClose(fp);
 348
 349   cupsdLogMessage(CUPSD_LOG_DEBUG2, "cupsdCreateProfile(job_id=%d,allow_networking=%d) = \"%s\"", job_id, allow_networking, profile);
 350   return ((void *)strdup(profile));
 351
 352 #else
 353   cupsdLogMessage(CUPSD_LOG_DEBUG2, "cupsdCreateProfile(job_id=%d, allow_networking=%d) = NULL", job_id, allow_networking);
 354
 355   return (NULL);
 356 #endif /* HAVE_SANDBOX_H */
 357 }
 358
 359
 360 /*
 361  * 'cupsdDestroyProfile()' - Delete an execution profile.
 362  */
 363
 364 void
 365 cupsdDestroyProfile(void *profile)      /* I - Profile */
 366 {
 367   cupsdLogMessage(CUPSD_LOG_DEBUG2, "cupsdDeleteProfile(profile=\"%s\")",
 368                   profile ? (char *)profile : "(null)");
 369
 370 #ifdef HAVE_SANDBOX_H
 371   if (profile)
 372   {
 373     unlink((char *)profile);
 374     free(profile);
 375   }
 376 #endif /* HAVE_SANDBOX_H */
 377 }
 378
 379
 380 /*
 381  * 'cupsdEndProcess()' - End a process.
 382  */
 383
 384 int                                     /* O - 0 on success, -1 on failure */
 385 cupsdEndProcess(int pid,                /* I - Process ID */
 386                 int force)              /* I - Force child to die */
 387 {
 388   cupsdLogMessage(CUPSD_LOG_DEBUG2, "cupsdEndProcess(pid=%d, force=%d)", pid,
 389                   force);
 390
 391   if (!pid)
 392     return (0);
 393
 394   if (!RunUser)
 395   {
 396    /*
 397     * When running as root, cupsd puts child processes in their own process
 398     * group.  Using "-pid" sends a signal to all processes in the group.
 399     */
 400
 401     pid = -pid;
 402   }
 403
 404   if (force)
 405     return (kill(pid, SIGKILL));
 406   else
 407     return (kill(pid, SIGTERM));
 408 }
 409
 410
 411 /*
 412  * 'cupsdFinishProcess()' - Finish a process and get its name.
 413  */
 414
 415 const char *                            /* O - Process name */
 416 cupsdFinishProcess(int    pid,          /* I - Process ID */
 417                    char   *name,        /* I - Name buffer */
 418                    size_t namelen,      /* I - Size of name buffer */
 419                    int    *job_id)      /* O - Job ID pointer or NULL */
 420 {
 421   cupsd_proc_t  key,                    /* Search key */
 422                 *proc;                  /* Matching process */
 423
 424
 425   key.pid = pid;
 426
 427   if ((proc = (cupsd_proc_t *)cupsArrayFind(process_array, &key)) != NULL)
 428   {
 429     if (job_id)
 430       *job_id = proc->job_id;
 431
 432     strlcpy(name, proc->name, namelen);
 433     cupsArrayRemove(process_array, proc);
 434     free(proc);
 435   }
 436   else
 437   {
 438     if (job_id)
 439       *job_id = 0;
 440
 441     strlcpy(name, "unknown", namelen);
 442   }
 443
 444   cupsdLogMessage(CUPSD_LOG_DEBUG2, "cupsdFinishProcess(pid=%d, name=%p, namelen=" CUPS_LLFMT ", job_id=%p(%d)) = \"%s\"", pid, name, CUPS_LLCAST namelen, job_id, job_id ? *job_id : 0, name);
 445
 446   return (name);
 447 }
 448
 449
 450 /*
 451  * 'cupsdStartProcess()' - Start a process.
 452  */
 453
 454 int                                     /* O - Process ID or 0 */
 455 cupsdStartProcess(
 456     const char  *command,               /* I - Full path to command */
 457     char        *argv[],                /* I - Command-line arguments */
 458     char        *envp[],                /* I - Environment */
 459     int         infd,                   /* I - Standard input file descriptor */
 460     int         outfd,                  /* I - Standard output file descriptor */
 461     int         errfd,                  /* I - Standard error file descriptor */
 462     int         backfd,                 /* I - Backchannel file descriptor */
 463     int         sidefd,                 /* I - Sidechannel file descriptor */
 464     int         root,                   /* I - Run as root? */
 465     void        *profile,               /* I - Security profile to use */
 466     cupsd_job_t *job,                   /* I - Job associated with process */
 467     int         *pid)                   /* O - Process ID */
 468 {
 469   int           i;                      /* Looping var */
 470   const char    *exec_path = command;   /* Command to be exec'd */
 471   char          *real_argv[110],        /* Real command-line arguments */
 472                 cups_exec[1024],        /* Path to "cups-exec" program */
 473                 user_str[16],           /* User string */
 474                 group_str[16],          /* Group string */
 475                 nice_str[16];           /* FilterNice string */
 476   uid_t         user;                   /* Command UID */
 477   cupsd_proc_t  *proc;                  /* New process record */
 478 #if USE_POSIX_SPAWN
 479   posix_spawn_file_actions_t actions;   /* Spawn file actions */
 480   posix_spawnattr_t attrs;              /* Spawn attributes */
 481   sigset_t      defsignals;             /* Default signals */
 482 #elif defined(HAVE_SIGACTION) && !defined(HAVE_SIGSET)
 483   struct sigaction action;              /* POSIX signal handler */
 484 #endif /* USE_POSIX_SPAWN */
 485 #if defined(__APPLE__)
 486   char          processPath[1024],      /* CFProcessPath environment variable */
 487                 linkpath[1024];         /* Link path for symlinks... */
 488   int           linkbytes;              /* Bytes for link path */
 489 #endif /* __APPLE__ */
 490
 491
 492   *pid = 0;
 493
 494  /*
 495   * Figure out the UID for the child process...
 496   */
 497
 498   if (RunUser)
 499     user = RunUser;
 500   else if (root)
 501     user = 0;
 502   else
 503     user = User;
 504
 505  /*
 506   * Check the permissions of the command we are running...
 507   */
 508
 509   if (_cupsFileCheck(command, _CUPS_FILE_CHECK_PROGRAM, !RunUser,
 510                      cupsdLogFCMessage, job ? job->printer : NULL))
 511     return (0);
 512
 513 #if defined(__APPLE__)
 514   if (envp)
 515   {
 516    /*
 517     * Add special voodoo magic for macOS - this allows macOS programs to access
 518     * their bundle resources properly...
 519     */
 520
 521     if ((linkbytes = readlink(command, linkpath, sizeof(linkpath) - 1)) > 0)
 522     {
 523      /*
 524       * Yes, this is a symlink to the actual program, nul-terminate and
 525       * use it...
 526       */
 527
 528       linkpath[linkbytes] = '\0';
 529
 530       if (linkpath[0] == '/')
 531         snprintf(processPath, sizeof(processPath), "CFProcessPath=%s",
 532                  linkpath);
 533       else
 534         snprintf(processPath, sizeof(processPath), "CFProcessPath=%s/%s",
 535                  dirname((char *)command), linkpath);
 536     }
 537     else
 538       snprintf(processPath, sizeof(processPath), "CFProcessPath=%s", command);
 539
 540     envp[0] = processPath;              /* Replace <CFProcessPath> string */
 541   }
 542 #endif  /* __APPLE__ */
 543
 544  /*
 545   * Use helper program when we have a sandbox profile...
 546   */
 547
 548 #if !USE_POSIX_SPAWN
 549   if (profile)
 550 #endif /* !USE_POSIX_SPAWN */
 551   {
 552     snprintf(cups_exec, sizeof(cups_exec), "%s/daemon/cups-exec", ServerBin);
 553     snprintf(user_str, sizeof(user_str), "%d", user);
 554     snprintf(group_str, sizeof(group_str), "%d", Group);
 555     snprintf(nice_str, sizeof(nice_str), "%d", FilterNice);
 556
 557     real_argv[0] = cups_exec;
 558     real_argv[1] = (char *)"-g";
 559     real_argv[2] = group_str;
 560     real_argv[3] = (char *)"-n";
 561     real_argv[4] = nice_str;
 562     real_argv[5] = (char *)"-u";
 563     real_argv[6] = user_str;
 564     real_argv[7] = profile ? profile : "none";
 565     real_argv[8] = (char *)command;
 566
 567     for (i = 0;
 568          i < (int)(sizeof(real_argv) / sizeof(real_argv[0]) - 10) && argv[i];
 569          i ++)
 570       real_argv[i + 9] = argv[i];
 571
 572     real_argv[i + 9] = NULL;
 573
 574     argv      = real_argv;
 575     exec_path = cups_exec;
 576   }
 577
 578   if (LogLevel == CUPSD_LOG_DEBUG2)
 579   {
 580     cupsdLogMessage(CUPSD_LOG_DEBUG2, "cupsdStartProcess: Preparing to start \"%s\", arguments:", command);
 581
 582     for (i = 0; argv[i]; i ++)
 583       cupsdLogMessage(CUPSD_LOG_DEBUG2, "cupsdStartProcess: argv[%d] = \"%s\"", i, argv[i]);
 584   }
 585
 586 #if USE_POSIX_SPAWN
 587  /*
 588   * Setup attributes and file actions for the spawn...
 589   */
 590
 591   cupsdLogMessage(CUPSD_LOG_DEBUG2, "cupsdStartProcess: Setting spawn attributes.");
 592   sigemptyset(&defsignals);
 593   sigaddset(&defsignals, SIGTERM);
 594   sigaddset(&defsignals, SIGCHLD);
 595   sigaddset(&defsignals, SIGPIPE);
 596
 597   posix_spawnattr_init(&attrs);
 598   posix_spawnattr_setflags(&attrs, POSIX_SPAWN_SETPGROUP | POSIX_SPAWN_SETSIGDEF);
 599   posix_spawnattr_setpgroup(&attrs, 0);
 600   posix_spawnattr_setsigdefault(&attrs, &defsignals);
 601
 602   cupsdLogMessage(CUPSD_LOG_DEBUG2, "cupsdStartProcess: Setting file actions.");
 603   posix_spawn_file_actions_init(&actions);
 604   if (infd != 0)
 605   {
 606     if (infd < 0)
 607       posix_spawn_file_actions_addopen(&actions, 0, "/dev/null", O_RDONLY, 0);
 608     else
 609       posix_spawn_file_actions_adddup2(&actions, infd, 0);
 610   }
 611
 612   if (outfd != 1)
 613   {
 614     if (outfd < 0)
 615       posix_spawn_file_actions_addopen(&actions, 1, "/dev/null", O_WRONLY, 0);
 616     else
 617       posix_spawn_file_actions_adddup2(&actions, outfd, 1);
 618   }
 619
 620   if (errfd != 2)
 621   {
 622     if (errfd < 0)
 623       posix_spawn_file_actions_addopen(&actions, 2, "/dev/null", O_WRONLY, 0);
 624     else
 625       posix_spawn_file_actions_adddup2(&actions, errfd, 2);
 626   }
 627
 628   if (backfd != 3 && backfd >= 0)
 629     posix_spawn_file_actions_adddup2(&actions, backfd, 3);
 630
 631   if (sidefd != 4 && sidefd >= 0)
 632     posix_spawn_file_actions_adddup2(&actions, sidefd, 4);
 633
 634   cupsdLogMessage(CUPSD_LOG_DEBUG2, "cupsdStartProcess: Calling posix_spawn.");
 635
 636   if (posix_spawn(pid, exec_path, &actions, &attrs, argv, envp ? envp : environ))
 637   {
 638     cupsdLogMessage(CUPSD_LOG_ERROR, "Unable to fork %s - %s.", command, strerror(errno));
 639
 640     *pid = 0;
 641   }
 642   else
 643     cupsdLogMessage(CUPSD_LOG_DEBUG2, "cupsdStartProcess: pid=%d", (int)*pid);
 644
 645   posix_spawn_file_actions_destroy(&actions);
 646   posix_spawnattr_destroy(&attrs);
 647
 648 #else
 649  /*
 650   * Block signals before forking...
 651   */
 652
 653   cupsdHoldSignals();
 654
 655   if ((*pid = fork()) == 0)
 656   {
 657    /*
 658     * Child process goes here; update stderr as needed...
 659     */
 660
 661     if (errfd != 2)
 662     {
 663       if (errfd < 0)
 664         errfd = open("/dev/null", O_WRONLY);
 665
 666       if (errfd != 2)
 667       {
 668         dup2(errfd, 2);
 669         close(errfd);
 670       }
 671     }
 672
 673    /*
 674     * Put this process in its own process group so that we can kill any child
 675     * processes it creates.
 676     */
 677
 678 #  ifdef HAVE_SETPGID
 679     if (!RunUser && setpgid(0, 0))
 680       exit(errno + 100);
 681 #  else
 682     if (!RunUser && setpgrp())
 683       exit(errno + 100);
 684 #  endif /* HAVE_SETPGID */
 685
 686    /*
 687     * Update the remaining file descriptors as needed...
 688     */
 689
 690     if (infd != 0)
 691     {
 692       if (infd < 0)
 693         infd = open("/dev/null", O_RDONLY);
 694
 695       if (infd != 0)
 696       {
 697         dup2(infd, 0);
 698         close(infd);
 699       }
 700     }
 701
 702     if (outfd != 1)
 703     {
 704       if (outfd < 0)
 705         outfd = open("/dev/null", O_WRONLY);
 706
 707       if (outfd != 1)
 708       {
 709         dup2(outfd, 1);
 710         close(outfd);
 711       }
 712     }
 713
 714     if (backfd != 3 && backfd >= 0)
 715     {
 716       dup2(backfd, 3);
 717       close(backfd);
 718       fcntl(3, F_SETFL, O_NDELAY);
 719     }
 720
 721     if (sidefd != 4 && sidefd >= 0)
 722     {
 723       dup2(sidefd, 4);
 724       close(sidefd);
 725       fcntl(4, F_SETFL, O_NDELAY);
 726     }
 727
 728    /*
 729     * Change the priority of the process based on the FilterNice setting.
 730     * (this is not done for root processes...)
 731     */
 732
 733     if (!root)
 734       nice(FilterNice);
 735
 736    /*
 737     * Reset group membership to just the main one we belong to.
 738     */
 739
 740     if (!RunUser && setgid(Group))
 741       exit(errno + 100);
 742
 743     if (!RunUser && setgroups(1, &Group))
 744       exit(errno + 100);
 745
 746    /*
 747     * Change user to something "safe"...
 748     */
 749
 750     if (!RunUser && user && setuid(user))
 751       exit(errno + 100);
 752
 753    /*
 754     * Change umask to restrict permissions on created files...
 755     */
 756
 757     umask(077);
 758
 759    /*
 760     * Unblock signals before doing the exec...
 761     */
 762
 763 #  ifdef HAVE_SIGSET
 764     sigset(SIGTERM, SIG_DFL);
 765     sigset(SIGCHLD, SIG_DFL);
 766     sigset(SIGPIPE, SIG_DFL);
 767 #  elif defined(HAVE_SIGACTION)
 768     memset(&action, 0, sizeof(action));
 769
 770     sigemptyset(&action.sa_mask);
 771     action.sa_handler = SIG_DFL;
 772
 773     sigaction(SIGTERM, &action, NULL);
 774     sigaction(SIGCHLD, &action, NULL);
 775     sigaction(SIGPIPE, &action, NULL);
 776 #  else
 777     signal(SIGTERM, SIG_DFL);
 778     signal(SIGCHLD, SIG_DFL);
 779     signal(SIGPIPE, SIG_DFL);
 780 #  endif /* HAVE_SIGSET */
 781
 782     cupsdReleaseSignals();
 783
 784    /*
 785     * Execute the command; if for some reason this doesn't work, log an error
 786     * exit with a non-zero value...
 787     */
 788
 789     if (envp)
 790       execve(exec_path, argv, envp);
 791     else
 792       execv(exec_path, argv);
 793
 794     exit(errno + 100);
 795   }
 796   else if (*pid < 0)
 797   {
 798    /*
 799     * Error - couldn't fork a new process!
 800     */
 801
 802     cupsdLogMessage(CUPSD_LOG_ERROR, "Unable to fork %s - %s.", command,
 803                     strerror(errno));
 804
 805     *pid = 0;
 806   }
 807
 808   cupsdReleaseSignals();
 809 #endif /* USE_POSIX_SPAWN */
 810
 811   if (*pid)
 812   {
 813     if (!process_array)
 814       process_array = cupsArrayNew((cups_array_func_t)compare_procs, NULL);
 815
 816     if (process_array)
 817     {
 818       if ((proc = calloc(1, sizeof(cupsd_proc_t) + strlen(command))) != NULL)
 819       {
 820         proc->pid    = *pid;
 821         proc->job_id = job ? job->id : 0;
 822         _cups_strcpy(proc->name, command);
 823
 824         cupsArrayAdd(process_array, proc);
 825       }
 826     }
 827   }
 828
 829   cupsdLogMessage(CUPSD_LOG_DEBUG2,
 830                   "cupsdStartProcess(command=\"%s\", argv=%p, envp=%p, "
 831                   "infd=%d, outfd=%d, errfd=%d, backfd=%d, sidefd=%d, root=%d, "
 832                   "profile=%p, job=%p(%d), pid=%p) = %d",
 833                   command, argv, envp, infd, outfd, errfd, backfd, sidefd,
 834                   root, profile, job, job ? job->id : 0, pid, *pid);
 835
 836   return (*pid);
 837 }
 838
 839
 840 /*
 841  * 'compare_procs()' - Compare two processes.
 842  */
 843
 844 static int                              /* O - Result of comparison */
 845 compare_procs(cupsd_proc_t *a,          /* I - First process */
 846               cupsd_proc_t *b)          /* I - Second process */
 847 {
 848   return (a->pid - b->pid);
 849 }
 850
 851
 852 #ifdef HAVE_SANDBOX_H
 853 /*
 854  * 'cupsd_requote()' - Make a regular-expression version of a string.
 855  */
 856
 857 static char *                           /* O - Quoted string */
 858 cupsd_requote(char       *dst,          /* I - Destination buffer */
 859               const char *src,          /* I - Source string */
 860               size_t     dstsize)       /* I - Size of destination buffer */
 861 {
 862   int   ch;                             /* Current character */
 863   char  *dstptr,                        /* Current position in buffer */
 864         *dstend;                        /* End of destination buffer */
 865
 866
 867   dstptr = dst;
 868   dstend = dst + dstsize - 2;
 869
 870   while (*src && dstptr < dstend)
 871   {
 872     ch = *src++;
 873
 874     if (ch == '/' && !*src)
 875       break;                            /* Don't add trailing slash */
 876
 877     if (strchr(".?*()[]^$\\", ch))
 878       *dstptr++ = '\\';
 879
 880     *dstptr++ = (char)ch;
 881   }
 882
 883   *dstptr = '\0';
 884
 885   return (dst);
 886 }
 887 #endif /* HAVE_SANDBOX_H */