nix/nix-daemon/guix-daemon.cc

   1 /* GNU Guix --- Functional package management for GNU
   2    Copyright (C) 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2021 Ludovic Courtès <ludo@gnu.org>
   3    Copyright (C) 2006, 2010, 2012, 2014 Eelco Dolstra <e.dolstra@tudelft.nl>
   4
   5    This file is part of GNU Guix.
   6
   7    GNU Guix is free software; you can redistribute it and/or modify it
   8    under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or (at
  10    your option) any later version.
  11
  12    GNU Guix is distributed in the hope that it will be useful, but
  13    WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include <config.h>
  21
  22 #include <types.hh>
  23 #include "shared.hh"
  24 #include <globals.hh>
  25 #include <util.hh>
  26
  27 #include <gcrypt.h>
  28
  29 #include <stdlib.h>
  30 #include <argp.h>
  31 #include <unistd.h>
  32 #include <sys/types.h>
  33 #include <sys/stat.h>
  34 #include <sys/socket.h>
  35 #include <sys/un.h>
  36 #include <netdb.h>
  37 #include <strings.h>
  38 #include <exception>
  39 #include <iostream>
  40
  41 #include <libintl.h>
  42 #include <locale.h>
  43
  44 /* Variables used by `nix-daemon.cc'.  */
  45 volatile ::sig_atomic_t blockInt;
  46 char **argvSaved;
  47
  48 using namespace nix;
  49
  50 /* Entry point in `nix-daemon.cc'.  */
  51 extern void run (const std::vector<int> &);
  52
  53 \f
  54 /* Command-line options.  */
  55
  56 #define n_(str)  str
  57 #define _(str)   gettext (str)
  58 static const char guix_textdomain[] = "guix";
  59
  60
  61 const char *argp_program_version =
  62   "guix-daemon (" PACKAGE_NAME ") " PACKAGE_VERSION;
  63 const char *argp_program_bug_address = PACKAGE_BUGREPORT;
  64
  65 static char doc[] =
  66   n_("guix-daemon -- perform derivation builds and store accesses")
  67   "\v\n"
  68   n_("This program is a daemon meant to run in the background.  It serves \
  69 requests sent over a Unix-domain socket.  It accesses the store, and \
  70 builds derivations on behalf of its clients.");
  71
  72 #define GUIX_OPT_SYSTEM 1
  73 #define GUIX_OPT_DISABLE_CHROOT 2
  74 #define GUIX_OPT_BUILD_USERS_GROUP 3
  75 #define GUIX_OPT_CACHE_FAILURES 4
  76 #define GUIX_OPT_LOSE_LOGS 5
  77 #define GUIX_OPT_DISABLE_LOG_COMPRESSION 6
  78 #define GUIX_OPT_DISABLE_DEDUPLICATION 7
  79 #define GUIX_OPT_IMPERSONATE_LINUX_26 8
  80 #define GUIX_OPT_DEBUG 9
  81 #define GUIX_OPT_CHROOT_DIR 10
  82 #define GUIX_OPT_LISTEN 11
  83 #define GUIX_OPT_NO_SUBSTITUTES 12
  84 #define GUIX_OPT_SUBSTITUTE_URLS 13
  85 #define GUIX_OPT_NO_BUILD_HOOK 14
  86 #define GUIX_OPT_GC_KEEP_OUTPUTS 15
  87 #define GUIX_OPT_GC_KEEP_DERIVATIONS 16
  88 #define GUIX_OPT_BUILD_ROUNDS 17
  89 #define GUIX_OPT_TIMEOUT 18
  90 #define GUIX_OPT_MAX_SILENT_TIME 19
  91 #define GUIX_OPT_LOG_COMPRESSION 20
  92 #define GUIX_OPT_DISCOVER 21
  93
  94 static const struct argp_option options[] =
  95   {
  96     { "system", GUIX_OPT_SYSTEM, n_("SYSTEM"), 0,
  97       n_("assume SYSTEM as the current system type") },
  98     { "cores", 'c', n_("N"), 0,
  99       n_("use N CPU cores to build each derivation; 0 means as many as available")
 100     },
 101     { "max-jobs", 'M', n_("N"), 0,
 102       n_("allow at most N build jobs") },
 103     { "timeout", GUIX_OPT_TIMEOUT, n_("SECONDS"), 0,
 104       n_("mark builds as failed after SECONDS of activity") },
 105     { "max-silent-time", GUIX_OPT_MAX_SILENT_TIME, n_("SECONDS"), 0,
 106       n_("mark builds as failed after SECONDS of silence") },
 107     { "disable-chroot", GUIX_OPT_DISABLE_CHROOT, 0, 0,
 108       n_("disable chroot builds") },
 109     { "chroot-directory", GUIX_OPT_CHROOT_DIR, n_("DIR"), 0,
 110       n_("add DIR to the build chroot") },
 111     { "build-users-group", GUIX_OPT_BUILD_USERS_GROUP, n_("GROUP"), 0,
 112       n_("perform builds as a user of GROUP") },
 113     { "no-substitutes", GUIX_OPT_NO_SUBSTITUTES, 0, 0,
 114       n_("do not use substitutes") },
 115     { "substitute-urls", GUIX_OPT_SUBSTITUTE_URLS, n_("URLS"), 0,
 116       n_("use URLS as the default list of substitute providers") },
 117     { "no-offload", GUIX_OPT_NO_BUILD_HOOK, 0, 0,
 118       n_("do not attempt to offload builds") },
 119     { "no-build-hook", GUIX_OPT_NO_BUILD_HOOK, 0,
 120       OPTION_HIDDEN,                              // deprecated
 121       n_("do not attempt to offload builds") },
 122     { "cache-failures", GUIX_OPT_CACHE_FAILURES, 0, 0,
 123       n_("cache build failures") },
 124     { "rounds", GUIX_OPT_BUILD_ROUNDS, "N", 0,
 125       n_("build each derivation N times in a row") },
 126     { "lose-logs", GUIX_OPT_LOSE_LOGS, 0, 0,
 127       n_("do not keep build logs") },
 128     { "disable-log-compression", GUIX_OPT_DISABLE_LOG_COMPRESSION, 0,
 129       OPTION_HIDDEN,                              // deprecated
 130       n_("disable compression of the build logs") },
 131     { "log-compression", GUIX_OPT_LOG_COMPRESSION, "TYPE", 0,
 132       n_("use the specified compression type for build logs") },
 133     { "discover", GUIX_OPT_DISCOVER, "yes/no", OPTION_ARG_OPTIONAL,
 134       n_("use substitute servers discovered on the local network") },
 135
 136     /* '--disable-deduplication' was known as '--disable-store-optimization'
 137        up to Guix 0.7 included, so keep the alias around.  */
 138     { "disable-deduplication", GUIX_OPT_DISABLE_DEDUPLICATION, 0, 0,
 139       n_("disable automatic file \"deduplication\" in the store") },
 140     { "disable-store-optimization", GUIX_OPT_DISABLE_DEDUPLICATION, 0,
 141       OPTION_ALIAS | OPTION_HIDDEN, NULL },
 142
 143     { "impersonate-linux-2.6", GUIX_OPT_IMPERSONATE_LINUX_26, 0,
 144 #ifdef HAVE_SYS_PERSONALITY_H
 145       0,
 146 #else
 147       OPTION_HIDDEN,
 148 #endif
 149       n_("impersonate Linux 2.6")
 150     },
 151     { "gc-keep-outputs", GUIX_OPT_GC_KEEP_OUTPUTS,
 152       "yes/no", OPTION_ARG_OPTIONAL,
 153       n_("tell whether the GC must keep outputs of live derivations") },
 154     { "gc-keep-derivations", GUIX_OPT_GC_KEEP_DERIVATIONS,
 155       "yes/no", OPTION_ARG_OPTIONAL,
 156       n_("tell whether the GC must keep derivations corresponding \
 157 to live outputs") },
 158
 159     { "listen", GUIX_OPT_LISTEN, n_("SOCKET"), 0,
 160       n_("listen for connections on SOCKET") },
 161     { "debug", GUIX_OPT_DEBUG, 0, 0,
 162       n_("produce debugging output") },
 163     { 0, 0, 0, 0, 0 }
 164   };
 165
 166
 167 /* Default port for '--listen' on TCP/IP.  */
 168 #define DEFAULT_GUIX_PORT "44146"
 169
 170 /* List of '--listen' options.  */
 171 static std::list<std::string> listen_options;
 172
 173 static bool useDiscover = false;
 174
 175 /* Convert ARG to a Boolean value, or throw an error if it does not denote a
 176    Boolean.  */
 177 static bool
 178 string_to_bool (const char *arg, bool dflt = true)
 179 {
 180   if (arg == NULL)
 181     return dflt;
 182   else if (strcasecmp (arg, "yes") == 0)
 183     return true;
 184   else if (strcasecmp (arg, "no") == 0)
 185     return false;
 186   else
 187     throw nix::Error (format ("'%1%': invalid Boolean value") % arg);
 188 }
 189
 190 /* Parse a single option. */
 191 static error_t
 192 parse_opt (int key, char *arg, struct argp_state *state)
 193 {
 194   switch (key)
 195     {
 196     case GUIX_OPT_DISABLE_CHROOT:
 197       settings.useChroot = false;
 198       break;
 199     case GUIX_OPT_CHROOT_DIR:
 200       {
 201         std::string chroot_dirs;
 202
 203         chroot_dirs = settings.get ("build-extra-chroot-dirs",
 204                                     (std::string) "");
 205         if (chroot_dirs == "")
 206           chroot_dirs = arg;
 207         else
 208           chroot_dirs = chroot_dirs + " " + arg;
 209         settings.set("build-extra-chroot-dirs", chroot_dirs);
 210         break;
 211       }
 212     case GUIX_OPT_LOG_COMPRESSION:
 213       if (strcmp (arg, "none") == 0)
 214         settings.logCompression = COMPRESSION_NONE;
 215       else if (strcmp (arg, "gzip") == 0)
 216         settings.logCompression = COMPRESSION_GZIP;
 217 #if HAVE_BZLIB_H
 218       else if (strcmp (arg, "bzip2") == 0)
 219         settings.logCompression = COMPRESSION_BZIP2;
 220 #endif
 221       else
 222         {
 223           fprintf (stderr, _("error: %s: unknown compression type\n"), arg);
 224           exit (EXIT_FAILURE);
 225         }
 226       break;
 227     case GUIX_OPT_DISABLE_LOG_COMPRESSION:
 228       settings.logCompression = COMPRESSION_NONE;
 229       break;
 230     case GUIX_OPT_BUILD_USERS_GROUP:
 231       settings.buildUsersGroup = arg;
 232       break;
 233     case GUIX_OPT_DISABLE_DEDUPLICATION:
 234       settings.autoOptimiseStore = false;
 235       break;
 236     case GUIX_OPT_CACHE_FAILURES:
 237       settings.cacheFailure = true;
 238       break;
 239     case GUIX_OPT_BUILD_ROUNDS:
 240       {
 241         char *end;
 242         unsigned long n = strtoul (arg, &end, 10);
 243         if (end != arg + strlen (arg))
 244           {
 245             fprintf (stderr, _("error: %s: invalid number of rounds\n"), arg);
 246             exit (EXIT_FAILURE);
 247           }
 248         settings.set ("build-repeat", std::to_string (std::max (0UL, n - 1)));
 249         break;
 250       }
 251     case GUIX_OPT_IMPERSONATE_LINUX_26:
 252       settings.impersonateLinux26 = true;
 253       break;
 254     case GUIX_OPT_LOSE_LOGS:
 255       settings.keepLog = false;
 256       break;
 257     case GUIX_OPT_LISTEN:
 258       listen_options.push_back (arg);
 259       break;
 260     case GUIX_OPT_SUBSTITUTE_URLS:
 261       settings.set ("substitute-urls", arg);
 262       break;
 263     case GUIX_OPT_NO_SUBSTITUTES:
 264       settings.set ("build-use-substitutes", "false");
 265       break;
 266     case GUIX_OPT_NO_BUILD_HOOK:
 267       settings.useBuildHook = false;
 268       break;
 269     case GUIX_OPT_DISCOVER:
 270       useDiscover = string_to_bool (arg);
 271       settings.set ("discover", useDiscover ? "true" : "false");
 272       break;
 273     case GUIX_OPT_DEBUG:
 274       verbosity = lvlDebug;
 275       break;
 276     case GUIX_OPT_GC_KEEP_OUTPUTS:
 277       settings.gcKeepOutputs = string_to_bool (arg);
 278       break;
 279     case GUIX_OPT_GC_KEEP_DERIVATIONS:
 280       settings.gcKeepDerivations = string_to_bool (arg);
 281       break;
 282     case 'c':
 283       settings.set ("build-cores", arg);
 284       break;
 285     case 'M':
 286       settings.set ("build-max-jobs", arg);
 287       break;
 288     case GUIX_OPT_TIMEOUT:
 289       settings.set ("build-timeout", arg);
 290       break;
 291     case GUIX_OPT_MAX_SILENT_TIME:
 292       settings.set ("build-max-silent-time", arg);
 293       break;
 294     case GUIX_OPT_SYSTEM:
 295       settings.thisSystem = arg;
 296       break;
 297     default:
 298       return (error_t) ARGP_ERR_UNKNOWN;
 299     }
 300
 301   return (error_t) 0;
 302 }
 303
 304 /* Argument parsing.  */
 305 static const struct argp argp =
 306   {
 307     options, parse_opt,
 308     NULL, doc,
 309     NULL, NULL,                                   // children and help_filter
 310     guix_textdomain
 311   };
 312
 313 \f
 314 static int
 315 open_unix_domain_socket (const char *file)
 316 {
 317   /* Create and bind to a Unix domain socket. */
 318   AutoCloseFD fdSocket = socket (PF_UNIX, SOCK_STREAM, 0);
 319   if (fdSocket == -1)
 320     throw SysError (_("cannot create Unix domain socket"));
 321
 322   createDirs (dirOf (file));
 323
 324   /* Urgh, sockaddr_un allows path names of only 108 characters.
 325      So chdir to the socket directory so that we can pass a
 326      relative path name. */
 327   if (chdir (dirOf (file).c_str ()) == -1)
 328     throw SysError (_("cannot change current directory"));
 329   Path fileRel = "./" + baseNameOf (file);
 330
 331   struct sockaddr_un addr;
 332   addr.sun_family = AF_UNIX;
 333   if (fileRel.size () >= sizeof (addr.sun_path))
 334     throw Error (format (_("socket file name '%1%' is too long")) % fileRel);
 335   strcpy (addr.sun_path, fileRel.c_str ());
 336
 337   unlink (file);
 338
 339   /* Make sure that the socket is created with 0666 permission
 340      (everybody can connect --- provided they have access to the
 341      directory containing the socket). */
 342   mode_t oldMode = umask (0111);
 343   int res = bind (fdSocket, (struct sockaddr *) &addr, sizeof addr);
 344   umask (oldMode);
 345   if (res == -1)
 346     throw SysError (format (_("cannot bind to socket '%1%'")) % file);
 347
 348   if (chdir ("/") == -1) /* back to the root */
 349     throw SysError (_("cannot change current directory"));
 350
 351   if (listen (fdSocket, 5) == -1)
 352     throw SysError (format (_("cannot listen on socket '%1%'")) % file);
 353
 354   return fdSocket.borrow ();
 355 }
 356
 357 /* Return a listening socket for ADDRESS, which has the given LENGTH.  */
 358 static int
 359 open_inet_socket (const struct sockaddr *address, socklen_t length)
 360 {
 361   AutoCloseFD fd = socket (address->sa_family, SOCK_STREAM, 0);
 362   if (fd == -1)
 363     throw SysError (_("cannot create TCP socket"));
 364
 365   int res = bind (fd, address, length);
 366   if (res == -1)
 367     throw SysError (_("cannot bind TCP socket"));
 368
 369   if (listen (fd, 5) == -1)
 370     throw SysError (format (_("cannot listen on TCP socket")));
 371
 372   return fd.borrow ();
 373 }
 374
 375 /* Return a list of file descriptors of listening sockets.  */
 376 static std::vector<int>
 377 listening_sockets (const std::list<std::string> &options)
 378 {
 379   std::vector<int> result;
 380
 381   if (options.empty ())
 382     {
 383       /* Open the default Unix-domain socket.  */
 384       auto fd = open_unix_domain_socket (settings.nixDaemonSocketFile.c_str ());
 385       result.push_back (fd);
 386       return result;
 387     }
 388
 389   /* Open the user-specified sockets.  */
 390   for (const std::string& option: options)
 391     {
 392       if (option[0] == '/')
 393         {
 394           /* Assume OPTION is the file name of a Unix-domain socket.  */
 395           settings.nixDaemonSocketFile = canonPath (option);
 396           int fd =
 397             open_unix_domain_socket (settings.nixDaemonSocketFile.c_str ());
 398           result.push_back (fd);
 399         }
 400       else
 401         {
 402           /* Assume OPTIONS has the form "HOST" or "HOST:PORT".  */
 403           auto colon = option.find_last_of (":");
 404           auto host = colon == std::string::npos
 405             ? option : option.substr (0, colon);
 406           auto port = colon == std::string::npos
 407             ? DEFAULT_GUIX_PORT
 408             : option.substr (colon + 1, option.size () - colon - 1);
 409
 410           struct addrinfo *res, hints;
 411
 412           memset (&hints, '\0', sizeof hints);
 413           hints.ai_socktype = SOCK_STREAM;
 414           hints.ai_flags = AI_NUMERICSERV | AI_ADDRCONFIG;
 415
 416           int err = getaddrinfo (host.c_str(), port.c_str (),
 417                                  &hints, &res);
 418
 419           if (err != 0)
 420             throw Error(format ("failed to look up '%1%': %2%")
 421                         % option % gai_strerror (err));
 422
 423           printMsg (lvlDebug, format ("listening on '%1%', port '%2%'")
 424                     % host % port);
 425
 426           /* XXX: Pick the first result, RES.  */
 427           result.push_back (open_inet_socket (res->ai_addr,
 428                                               res->ai_addrlen));
 429
 430           freeaddrinfo (res);
 431         }
 432     }
 433
 434   return result;
 435 }
 436
 437 \f
 438 int
 439 main (int argc, char *argv[])
 440 {
 441   setlocale (LC_ALL, "");
 442   bindtextdomain (guix_textdomain, LOCALEDIR);
 443   textdomain (guix_textdomain);
 444
 445   /* Initialize libgcrypt.  */
 446   if (!gcry_check_version (GCRYPT_VERSION))
 447     {
 448       fprintf (stderr, _("error: libgcrypt version mismatch\n"));
 449       exit (EXIT_FAILURE);
 450     }
 451
 452   /* Tell Libgcrypt that initialization has completed, as per the Libgcrypt
 453      1.6.0 manual (although this does not appear to be strictly needed.)  */
 454   gcry_control (GCRYCTL_INITIALIZATION_FINISHED, 0);
 455
 456   /* Set the umask so that the daemon does not end up creating group-writable
 457      files, which would lead to "suspicious ownership or permission" errors.
 458      See <http://lists.gnu.org/archive/html/bug-guix/2013-07/msg00033.html>.  */
 459   umask (S_IWGRP | S_IWOTH);
 460
 461 #ifndef HAVE_CHROOT
 462 # error chroot is assumed to be available
 463 #endif
 464
 465   /* Always use chroots by default.  */
 466   settings.useChroot = true;
 467
 468   /* Turn automatic deduplication on by default.  */
 469   settings.autoOptimiseStore = true;
 470
 471   /* Default to using as many cores as possible and one job at a time.  */
 472   settings.buildCores = 0;
 473   settings.maxBuildJobs = 1;
 474
 475   argvSaved = argv;
 476
 477   try
 478     {
 479       settings.processEnvironment ();
 480
 481       /* Enable substitutes by default.  */
 482       settings.set ("build-use-substitutes", "true");
 483
 484       /* Use our substitute server by default.  */
 485       settings.set ("substitute-urls", GUIX_SUBSTITUTE_URLS);
 486
 487 #ifdef HAVE_DAEMON_OFFLOAD_HOOK
 488       /* Use 'guix offload' for distributed builds by default.  */
 489       settings.useBuildHook = true;
 490 #else
 491       /* We are not installing any build hook, so disable it.  */
 492       settings.useBuildHook = false;
 493 #endif
 494
 495       argp_parse (&argp, argc, argv, 0, 0, 0);
 496
 497       auto sockets = listening_sockets (listen_options);
 498
 499       /* Effect all the changes made via 'settings.set'.  */
 500       settings.update ();
 501       printMsg(lvlDebug,
 502                format ("build log compression: %1%") % settings.logCompression);
 503
 504       if (geteuid () == 0 && settings.buildUsersGroup.empty ())
 505         fprintf (stderr, _("warning: daemon is running as root, so \
 506 using `--build-users-group' is highly recommended\n"));
 507
 508       if (settings.useChroot)
 509         {
 510           std::string chroot_dirs;
 511
 512           chroot_dirs = settings.get ("build-extra-chroot-dirs",
 513                                       (std::string) "");
 514           printMsg (lvlDebug,
 515                     format ("extra chroot directories: '%1%'") % chroot_dirs);
 516         }
 517
 518       if (useDiscover)
 519       {
 520         Strings args;
 521
 522         args.push_back("guix");
 523         args.push_back("discover");
 524
 525         startProcess([&]() {
 526           execv(settings.guixProgram.c_str(), stringsToCharPtrs(args).data());
 527         });
 528       }
 529
 530       printMsg (lvlDebug,
 531                 format ("automatic deduplication set to %1%")
 532                 % settings.autoOptimiseStore);
 533
 534       printMsg (lvlDebug,
 535                 format ("listening on `%1%'") % settings.nixDaemonSocketFile);
 536
 537       run (sockets);
 538     }
 539   catch (std::exception &e)
 540     {
 541       fprintf (stderr, _("error: %s\n"), e.what ());
 542       return EXIT_FAILURE;
 543     }
 544
 545   return EXIT_SUCCESS;                            /* never reached */
 546 }