keyd.c

   1 /*
   2  * keyd.c - key retrieval daemon
   3  *
   4  * Copyright 2004,2011 Jonathan McDowell <noodles@earth.li>
   5  *
   6  * This program is free software: you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the Free
   8  * Software Foundation; version 2 of the License.
   9  *
  10  * This program is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  13  * more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along with
  16  * this program; if not, write to the Free Software Foundation, Inc., 51
  17  * Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  */
  19
  20 #include <errno.h>
  21 #include <fcntl.h>
  22 #include <getopt.h>
  23 #include <signal.h>
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <sys/select.h>
  28 #include <sys/socket.h>
  29 #include <sys/types.h>
  30 #include <sys/un.h>
  31 #include <time.h>
  32 #include <unistd.h>
  33
  34 #include "charfuncs.h"
  35 #include "cleanup.h"
  36 #include "keyd.h"
  37 #include "keydb.h"
  38 #include "keyid.h"
  39 #include "keystructs.h"
  40 #include "log.h"
  41 #include "mem.h"
  42 #include "onak-conf.h"
  43 #include "parsekey.h"
  44 #include "version.h"
  45
  46 /* Maximum number of clients we're prepared to accept at once */
  47 #define MAX_CLIENTS 16
  48
  49 static struct keyd_stats *stats;
  50
  51 static void daemonize(void)
  52 {
  53         pid_t pid;
  54
  55         pid = fork();
  56
  57         if (pid < 0) {
  58                 logthing(LOGTHING_CRITICAL,
  59                         "Failed to fork into background: %d (%s)",
  60                         errno,
  61                         strerror(errno));
  62                 exit(EXIT_FAILURE);
  63         } else if (pid > 0) {
  64                 logthing(LOGTHING_INFO, "Backgrounded as pid %d.", pid);
  65                 exit(EXIT_SUCCESS);
  66         }
  67
  68         if (setsid() == -1) {
  69                 logthing(LOGTHING_CRITICAL,
  70                         "Couldn't set process group leader: %d (%s)",
  71                         errno,
  72                         strerror(errno));
  73                 exit(EXIT_FAILURE);
  74         }
  75
  76         if (!freopen("/dev/null", "r", stdin)) {
  77                 logthing(LOGTHING_CRITICAL,
  78                         "Couldn't reopen stdin to NULL: %d (%s)",
  79                         errno,
  80                         strerror(errno));
  81                 exit(EXIT_FAILURE);
  82         }
  83         if (!freopen("/dev/null", "w", stdout)) {
  84                 logthing(LOGTHING_CRITICAL,
  85                         "Couldn't reopen stdout to NULL: %d (%s)",
  86                         errno,
  87                         strerror(errno));
  88                 exit(EXIT_FAILURE);
  89         }
  90         if (!freopen("/dev/null", "w", stderr)) {
  91                 logthing(LOGTHING_CRITICAL,
  92                         "Couldn't reopen stderr to NULL: %d (%s)",
  93                         errno,
  94                         strerror(errno));
  95                 exit(EXIT_FAILURE);
  96         }
  97
  98         return;
  99 }
 100
 101 static bool keyd_write_key(int fd, struct openpgp_publickey *key)
 102 {
 103         struct openpgp_packet_list *packets = NULL;
 104         struct openpgp_packet_list *list_end = NULL;
 105         struct buffer_ctx           storebuf;
 106         ssize_t written;
 107         bool    ok = true;
 108
 109         storebuf.offset = 0;
 110         storebuf.size = 8192;
 111         storebuf.buffer = malloc(8192);
 112
 113         flatten_publickey(key,
 114                                 &packets,
 115                                 &list_end);
 116         write_openpgp_stream(buffer_putchar,
 117                                 &storebuf,
 118                                 packets);
 119         logthing(LOGTHING_TRACE,
 120                                 "Sending %d bytes.",
 121                                 storebuf.offset);
 122         written = write(fd, &storebuf.offset,
 123                         sizeof(storebuf.offset));
 124         if (written == 0) {
 125                 ok = false;
 126         } else {
 127                 written = write(fd, storebuf.buffer,
 128                         storebuf.offset);
 129                 if (written != storebuf.offset) {
 130                         ok = false;
 131                 }
 132         }
 133
 134         free(storebuf.buffer);
 135         storebuf.buffer = NULL;
 136         storebuf.size = storebuf.offset = 0;
 137         free_packet_list(packets);
 138         packets = list_end = NULL;
 139
 140         return (ok);
 141 }
 142
 143 static bool keyd_write_reply(int fd, enum keyd_reply _reply)
 144 {
 145         uint32_t reply = _reply;
 146         ssize_t written;
 147         bool ok = true;
 148
 149         written = write(fd, &reply, sizeof(reply));
 150         if (written != sizeof(reply)) {
 151                 ok = false;
 152         }
 153
 154         return (ok);
 155 }
 156
 157 static bool keyd_write_size(int fd, size_t size)
 158 {
 159         ssize_t written;
 160         bool ok = true;
 161
 162         written = write(fd, &size, sizeof(size));
 163         if (written != sizeof(size)) {
 164                 ok = false;
 165         }
 166
 167         return (ok);
 168 }
 169
 170 static void iteratefunc(void *ctx, struct openpgp_publickey *key)
 171 {
 172         int      *fd = (int *) ctx;
 173         uint64_t  keyid;
 174
 175         if (key != NULL) {
 176                 get_keyid(key, &keyid);
 177                 logthing(LOGTHING_TRACE,
 178                                 "Iterating over 0x%016" PRIX64 ".",
 179                                 keyid);
 180
 181                 keyd_write_key(*fd, key);
 182         }
 183
 184         return;
 185 }
 186
 187 static int sock_init(const char *sockname)
 188 {
 189         struct sockaddr_un sock;
 190         int                fd = -1;
 191         int                ret = -1;
 192
 193         fd = socket(PF_UNIX, SOCK_STREAM, 0);
 194         if (fd != -1) {
 195                 ret = fcntl(fd, F_SETFD, FD_CLOEXEC);
 196         }
 197
 198         if (ret != -1) {
 199                 sock.sun_family = AF_UNIX;
 200                 strncpy(sock.sun_path, sockname, sizeof(sock.sun_path) - 1);
 201                 unlink(sockname);
 202                 ret = bind(fd, (struct sockaddr *) &sock, sizeof(sock));
 203         }
 204
 205         if (ret != -1) {
 206                 ret = listen(fd, 5);
 207                 if (ret == -1) {
 208                         close(fd);
 209                         fd = -1;
 210                 }
 211         }
 212
 213         return fd;
 214 }
 215
 216 static int sock_do(struct onak_dbctx *dbctx, int fd)
 217 {
 218         uint32_t cmd = KEYD_CMD_UNKNOWN;
 219         ssize_t  bytes = 0;
 220         ssize_t  count = 0;
 221         int      ret = 0;
 222         uint64_t keyid = 0;
 223         char     *search = NULL;
 224         struct openpgp_publickey *key = NULL;
 225         struct openpgp_packet_list *packets = NULL;
 226         struct buffer_ctx storebuf;
 227         struct skshash hash;
 228         struct openpgp_fingerprint fingerprint;
 229
 230         /*
 231          * Get the command from the client.
 232          */
 233         bytes = read(fd, &cmd, sizeof(cmd));
 234
 235         logthing(LOGTHING_DEBUG, "Read %d bytes, command: %d", bytes, cmd);
 236
 237         if (bytes != sizeof(cmd)) {
 238                 ret = 1;
 239         }
 240
 241         if (ret == 0) {
 242                 if (cmd < KEYD_CMD_LAST) {
 243                         stats->command_stats[cmd]++;
 244                 } else {
 245                         stats->command_stats[KEYD_CMD_UNKNOWN]++;
 246                 }
 247                 switch (cmd) {
 248                 case KEYD_CMD_VERSION:
 249                         if (!keyd_write_reply(fd, KEYD_REPLY_OK)) {
 250                                 ret = 1;
 251                         }
 252                         if (ret == 0) {
 253                                 cmd = sizeof(keyd_version);
 254                                 bytes = write(fd, &cmd, sizeof(cmd));
 255                                 if (bytes != sizeof(cmd)) {
 256                                         ret = 1;
 257                                 }
 258                         }
 259                         if (ret == 0) {
 260                                 bytes = write(fd, &keyd_version,
 261                                         sizeof(keyd_version));
 262                                 if (bytes != sizeof(keyd_version)) {
 263                                         ret = 1;
 264                                 }
 265                         }
 266                         break;
 267                 case KEYD_CMD_GET_ID:
 268                         if (!keyd_write_reply(fd, KEYD_REPLY_OK)) {
 269                                 ret = 1;
 270                         }
 271                         if (ret == 0) {
 272                                 bytes = read(fd, &keyid, sizeof(keyid));
 273                                 if (bytes != sizeof(keyid)) {
 274                                         ret = 1;
 275                                 }
 276                         }
 277                         if (ret == 0) {
 278                                 logthing(LOGTHING_INFO,
 279                                                 "Fetching 0x%" PRIX64
 280                                                 ", result: %d",
 281                                                 keyid,
 282                                                 dbctx->fetch_key_id(dbctx,
 283                                                         keyid,
 284                                                         &key, false));
 285                                 if (key != NULL) {
 286                                         keyd_write_key(fd, key);
 287                                         free_publickey(key);
 288                                         key = NULL;
 289                                 } else {
 290                                         if (!keyd_write_size(fd, 0)) {
 291                                                 ret = 1;
 292                                         }
 293                                 }
 294                         }
 295                         break;
 296                 case KEYD_CMD_GET_FP:
 297                         if (!keyd_write_reply(fd, KEYD_REPLY_OK)) {
 298                                 ret = 1;
 299                         }
 300                         if (ret == 0) {
 301                                 if ((read(fd, &bytes, 1) != 1) ||
 302                                                 (bytes > MAX_FINGERPRINT_LEN)) {
 303                                         ret = 1;
 304                                 } else {
 305                                         fingerprint.length = bytes;
 306                                         bytes = read(fd, fingerprint.fp,
 307                                                 fingerprint.length);
 308                                         if (bytes != fingerprint.length) {
 309                                                 ret = 1;
 310                                         }
 311                                 }
 312                         }
 313                         if (ret == 0) {
 314                                 logthing(LOGTHING_INFO,
 315                                                 "Fetching by fingerprint"
 316                                                 ", result: %d",
 317                                                 dbctx->fetch_key_fp(dbctx,
 318                                                         &fingerprint,
 319                                                         &key, false));
 320                                 if (key != NULL) {
 321                                         keyd_write_key(fd, key);
 322                                         free_publickey(key);
 323                                         key = NULL;
 324                                 } else {
 325                                         if (!keyd_write_size(fd, 0)) {
 326                                                 ret = 1;
 327                                         }
 328                                 }
 329                         }
 330                         break;
 331
 332                 case KEYD_CMD_GET_TEXT:
 333                         if (!keyd_write_reply(fd, KEYD_REPLY_OK)) {
 334                                 ret = 1;
 335                         }
 336                         if (ret == 0) {
 337                                 bytes = read(fd, &count, sizeof(count));
 338                                 if (bytes != sizeof(count)) {
 339                                         ret = 1;
 340                                 }
 341                         }
 342                         if (ret == 0) {
 343                                 search = malloc(count+1);
 344                                 bytes = read(fd, search, count);
 345                                 if (bytes != count) {
 346                                         ret = 1;
 347                                         break;
 348                                 }
 349                                 search[count] = 0;
 350                                 logthing(LOGTHING_INFO,
 351                                                 "Fetching %s, result: %d",
 352                                                 search,
 353                                                 dbctx->fetch_key_text(dbctx,
 354                                                         search, &key));
 355                                 if (key != NULL) {
 356                                         keyd_write_key(fd, key);
 357                                         free_publickey(key);
 358                                         key = NULL;
 359                                 } else {
 360                                         if (!keyd_write_size(fd, 0)) {
 361                                                 ret = 1;
 362                                         }
 363                                 }
 364                                 free(search);
 365                         }
 366                         break;
 367                 case KEYD_CMD_STORE:
 368                         if (!keyd_write_reply(fd, KEYD_REPLY_OK)) {
 369                                 ret = 1;
 370                         }
 371                         if (ret == 0) {
 372                                 bytes = read(fd, &storebuf.size,
 373                                         sizeof(storebuf.size));
 374                                 logthing(LOGTHING_TRACE, "Reading %d bytes.",
 375                                         storebuf.size);
 376                                 if (bytes != sizeof(storebuf.size)) {
 377                                         ret = 1;
 378                                 }
 379                         }
 380                         if (ret == 0 && storebuf.size > 0) {
 381                                 storebuf.buffer = malloc(storebuf.size);
 382                                 storebuf.offset = 0;
 383                                 bytes = count = 0;
 384                                 while (bytes >= 0 && count < storebuf.size) {
 385                                         bytes = read(fd,
 386                                                 &storebuf.buffer[count],
 387                                                 storebuf.size - count);
 388                                         logthing(LOGTHING_TRACE,
 389                                                         "Read %d bytes.",
 390                                                         bytes);
 391                                         count += bytes;
 392                                 }
 393                                 read_openpgp_stream(buffer_fetchchar,
 394                                                 &storebuf,
 395                                                 &packets,
 396                                                 0);
 397                                 parse_keys(packets, &key);
 398                                 dbctx->store_key(dbctx, key, false, false);
 399                                 free_packet_list(packets);
 400                                 packets = NULL;
 401                                 free_publickey(key);
 402                                 key = NULL;
 403                                 free(storebuf.buffer);
 404                                 storebuf.buffer = NULL;
 405                                 storebuf.size = storebuf.offset = 0;
 406                         }
 407                         break;
 408                 case KEYD_CMD_DELETE:
 409                         if (!keyd_write_reply(fd, KEYD_REPLY_OK)) {
 410                                 ret = 1;
 411                         }
 412                         if (ret == 0) {
 413                                 bytes = read(fd, &keyid, sizeof(keyid));
 414                                 if (bytes != sizeof(keyid)) {
 415                                         ret = 1;
 416                                 }
 417                         }
 418                         if (ret == 0) {
 419                                 logthing(LOGTHING_INFO,
 420                                                 "Deleting 0x%" PRIX64
 421                                                 ", result: %d",
 422                                                 keyid,
 423                                                 dbctx->delete_key(dbctx,
 424                                                         keyid, false));
 425                         }
 426                         break;
 427                 case KEYD_CMD_GETFULLKEYID:
 428                         if (!keyd_write_reply(fd, KEYD_REPLY_OK)) {
 429                                 ret = 1;
 430                         }
 431                         if (ret == 0) {
 432                                 bytes = read(fd, &keyid, sizeof(keyid));
 433                                 if (bytes != sizeof(keyid)) {
 434                                         ret = 1;
 435                                 }
 436                         }
 437                         if (ret == 0) {
 438                                 keyid = dbctx->getfullkeyid(dbctx, keyid);
 439                                 cmd = sizeof(keyid);
 440                                 bytes = write(fd, &cmd, sizeof(cmd));
 441                                 if (bytes != sizeof(cmd)) {
 442                                         ret = 1;
 443                                 }
 444                         }
 445                         if (ret == 0) {
 446                                 bytes = write(fd, &keyid, sizeof(keyid));
 447                                 if (bytes != sizeof(keyid)) {
 448                                         ret = 1;
 449                                 }
 450                         }
 451                         break;
 452                 case KEYD_CMD_KEYITER:
 453                         if (!keyd_write_reply(fd, KEYD_REPLY_OK)) {
 454                                 ret = 1;
 455                         }
 456                         if (ret == 0) {
 457                                 dbctx->iterate_keys(dbctx, iteratefunc,
 458                                         &fd);
 459                                 if (!keyd_write_size(fd, 0)) {
 460                                         ret = 1;
 461                                 }
 462                         }
 463                         break;
 464                 case KEYD_CMD_CLOSE:
 465                         /* We're going to close the FD even if this fails */
 466                         (void) keyd_write_reply(fd, KEYD_REPLY_OK);
 467                         ret = 1;
 468                         break;
 469                 case KEYD_CMD_QUIT:
 470                         /* We're going to quit even if this fails */
 471                         (void) keyd_write_reply(fd, KEYD_REPLY_OK);
 472                         logthing(LOGTHING_NOTICE,
 473                                 "Exiting due to quit request.");
 474                         ret = 1;
 475                         trytocleanup();
 476                         break;
 477                 case KEYD_CMD_STATS:
 478                         if (!keyd_write_reply(fd, KEYD_REPLY_OK)) {
 479                                 ret = 1;
 480                         }
 481                         if (ret == 0) {
 482                                 cmd = sizeof(*stats);
 483                                 bytes = write(fd, &cmd, sizeof(cmd));
 484                                 if (bytes != sizeof(cmd)) {
 485                                         ret = 1;
 486                                 }
 487                         }
 488                         if (ret == 0) {
 489                                 bytes = write(fd, stats, sizeof(*stats));
 490                                 if (bytes != sizeof(*stats)) {
 491                                         ret = 1;
 492                                 }
 493                         }
 494                         break;
 495                 case KEYD_CMD_GET_SKSHASH:
 496                         if (!keyd_write_reply(fd, KEYD_REPLY_OK)) {
 497                                 ret = 1;
 498                         }
 499                         if (ret == 0) {
 500                                 bytes = read(fd, hash.hash, sizeof(hash.hash));
 501                                 if (bytes != sizeof(hash.hash)) {
 502                                         ret = 1;
 503                                 }
 504                         }
 505                         if (ret == 0) {
 506                                 logthing(LOGTHING_INFO,
 507                                                 "Fetching by hash"
 508                                                 ", result: %d",
 509                                                 dbctx->fetch_key_skshash(dbctx,
 510                                                         &hash, &key));
 511                                 if (key != NULL) {
 512                                         keyd_write_key(fd, key);
 513                                         free_publickey(key);
 514                                         key = NULL;
 515                                 } else {
 516                                         if (!keyd_write_size(fd, 0)) {
 517                                                 ret = 1;
 518                                         }
 519                                 }
 520                         }
 521                         break;
 522
 523                 default:
 524                         logthing(LOGTHING_ERROR, "Got unknown command: %d",
 525                                         cmd);
 526                         if (!keyd_write_reply(fd, KEYD_REPLY_UNKNOWN_CMD)) {
 527                                 ret = 1;
 528                         }
 529                 }
 530         }
 531
 532         return(ret);
 533 }
 534
 535 static int sock_close(int fd)
 536 {
 537         shutdown(fd, SHUT_RDWR);
 538         return close(fd);
 539 }
 540
 541 static int sock_accept(int fd)
 542 {
 543         struct sockaddr_un sock;
 544         socklen_t          socklen;
 545         int    srv = -1;
 546         int    ret = -1;
 547
 548         socklen = sizeof(sock);
 549         srv = accept(fd, (struct sockaddr *) &sock, &socklen);
 550         if (srv != -1) {
 551                 ret = fcntl(srv, F_SETFD, FD_CLOEXEC);
 552         }
 553
 554         if (ret != -1) {
 555                 stats->connects++;
 556         }
 557
 558         return (srv);
 559 }
 560
 561 static void usage(void)
 562 {
 563         puts("keyd " ONAK_VERSION " - backend key serving daemon for the "
 564                 "onak PGP keyserver.\n");
 565         puts("Usage:\n");
 566         puts("\tkeyd [options]\n");
 567         puts("\tOptions:\n:");
 568         puts("-c <file> - use <file> as the config file");
 569         puts("-f        - run in the foreground");
 570         puts("-h        - show this help text");
 571         exit(EXIT_FAILURE);
 572 }
 573
 574 int main(int argc, char *argv[])
 575 {
 576         int fd = -1, maxfd, i, clients[MAX_CLIENTS];
 577         fd_set rfds;
 578         char sockname[1024];
 579         char *configfile = NULL;
 580         bool foreground = false;
 581         int optchar;
 582         struct onak_dbctx *dbctx;
 583
 584         while ((optchar = getopt(argc, argv, "c:fh")) != -1 ) {
 585                 switch (optchar) {
 586                 case 'c':
 587                         if (configfile != NULL) {
 588                                 free(configfile);
 589                         }
 590                         configfile = strdup(optarg);
 591                         break;
 592                 case 'f':
 593                         foreground = true;
 594                         break;
 595                 case 'h':
 596                 default:
 597                         usage();
 598                         break;
 599                 }
 600         }
 601
 602         readconfig(configfile);
 603         free(configfile);
 604         configfile = NULL;
 605         initlogthing("keyd", config.logfile);
 606         config.use_keyd = false;
 607
 608         if (!foreground) {
 609                 daemonize();
 610         }
 611
 612         catchsignals();
 613         signal(SIGPIPE, SIG_IGN);
 614
 615
 616         stats = calloc(1, sizeof(*stats));
 617         if (!stats) {
 618                 logthing(LOGTHING_ERROR,
 619                         "Couldn't allocate memory for stats structure.");
 620                 exit(EXIT_FAILURE);
 621         }
 622         stats->started = time(NULL);
 623
 624         snprintf(sockname, 1023, "%s/%s", config.db_dir, KEYD_SOCKET);
 625         fd = sock_init(sockname);
 626
 627         if (fd != -1) {
 628                 FD_ZERO(&rfds);
 629                 FD_SET(fd, &rfds);
 630                 maxfd = fd;
 631                 memset(clients, -1, sizeof (clients));
 632
 633                 dbctx = config.dbinit(false);
 634
 635                 logthing(LOGTHING_NOTICE, "Accepting connections.");
 636                 while (!cleanup() && select(maxfd + 1, &rfds, NULL, NULL, NULL) != -1) {
 637                         /*
 638                          * Deal with existing clients first; if we're at our
 639                          * connection limit then processing them might free
 640                          * things up and let us accept the next client below.
 641                          */
 642                         for (i = 0; i < MAX_CLIENTS; i++) {
 643                                 if (clients[i] != -1 &&
 644                                                 FD_ISSET(clients[i], &rfds)) {
 645                                         logthing(LOGTHING_DEBUG,
 646                                                 "Handling connection for client %d.", i);
 647                                         if (sock_do(dbctx, clients[i])) {
 648                                                 sock_close(clients[i]);
 649                                                 clients[i] = -1;
 650                                                 logthing(LOGTHING_DEBUG,
 651                                                         "Closed connection for client %d.", i);
 652                                         }
 653                                 }
 654                         }
 655                         /*
 656                          * Check if we have a new incoming connection to accept.
 657                          */
 658                         if (FD_ISSET(fd, &rfds)) {
 659                                 for (i = 0; i < MAX_CLIENTS; i++) {
 660                                         if (clients[i] == -1) {
 661                                                 break;
 662                                         }
 663                                 }
 664                                 if (i < MAX_CLIENTS) {
 665                                         logthing(LOGTHING_INFO,
 666                                                 "Accepted connection %d.", i);
 667                                         clients[i] = sock_accept(fd);
 668                                 }
 669                         }
 670                         FD_ZERO(&rfds);
 671                         FD_SET(fd, &rfds);
 672                         maxfd = fd;
 673                         for (i = 0; i < MAX_CLIENTS; i++) {
 674                                 if (clients[i] != -1) {
 675                                         FD_SET(clients[i], &rfds);
 676                                         maxfd = (maxfd > clients[i]) ?
 677                                                         maxfd : clients[i];
 678                                 }
 679                         }
 680                 }
 681                 dbctx->cleanupdb(dbctx);
 682                 sock_close(fd);
 683                 unlink(sockname);
 684         }
 685
 686         free(stats);
 687
 688         cleanuplogthing();
 689         cleanupconfig();
 690
 691         return(EXIT_SUCCESS);
 692 }