1 /* $NetBSD: main.c,v 1.14 2016/01/08 21:35:40 christos Exp $ */ 2 3 #include <config.h> 4 5 #include <event2/util.h> 6 #include <event2/event.h> 7 8 #include "ntp_workimpl.h" 9 #ifdef WORK_THREAD 10 # include <event2/thread.h> 11 #endif 12 13 #include "main.h" 14 #include "ntp_libopts.h" 15 #include "kod_management.h" 16 #include "networking.h" 17 #include "utilities.h" 18 #include "log.h" 19 #include "libntp.h" 20 21 22 int shutting_down; 23 int time_derived; 24 int time_adjusted; 25 int n_pending_dns = 0; 26 int n_pending_ntp = 0; 27 int ai_fam_pref = AF_UNSPEC; 28 int ntpver = 4; 29 double steplimit = -1; 30 SOCKET sock4 = -1; /* Socket for IPv4 */ 31 SOCKET sock6 = -1; /* Socket for IPv6 */ 32 /* 33 ** BCAST *must* listen on port 123 (by default), so we can only 34 ** use the UCST sockets (above) if they too are using port 123 35 */ 36 SOCKET bsock4 = -1; /* Broadcast Socket for IPv4 */ 37 SOCKET bsock6 = -1; /* Broadcast Socket for IPv6 */ 38 struct event_base *base; 39 struct event *ev_sock4; 40 struct event *ev_sock6; 41 struct event *ev_worker_timeout; 42 struct event *ev_xmt_timer; 43 44 struct dns_ctx { 45 const char * name; 46 int flags; 47 #define CTX_BCST 0x0001 48 #define CTX_UCST 0x0002 49 #define CTX_xCST 0x0003 50 #define CTX_CONC 0x0004 51 #define CTX_unused 0xfffd 52 int key_id; 53 struct timeval timeout; 54 struct key * key; 55 }; 56 57 typedef struct sent_pkt_tag sent_pkt; 58 struct sent_pkt_tag { 59 sent_pkt * link; 60 struct dns_ctx * dctx; 61 sockaddr_u addr; 62 time_t stime; 63 int done; 64 struct pkt x_pkt; 65 }; 66 67 typedef struct xmt_ctx_tag xmt_ctx; 68 struct xmt_ctx_tag { 69 xmt_ctx * link; 70 SOCKET sock; 71 time_t sched; 72 sent_pkt * spkt; 73 }; 74 75 struct timeval gap; 76 xmt_ctx * xmt_q; 77 struct key * keys = NULL; 78 int response_timeout; 79 struct timeval response_tv; 80 struct timeval start_tv; 81 /* check the timeout at least once per second */ 82 struct timeval wakeup_tv = { 0, 888888 }; 83 84 sent_pkt * fam_listheads[2]; 85 #define v4_pkts_list (fam_listheads[0]) 86 #define v6_pkts_list (fam_listheads[1]) 87 88 static union { 89 struct pkt pkt; 90 char buf[LEN_PKT_NOMAC + NTP_MAXEXTEN + MAX_MAC_LEN]; 91 } rbuf; 92 93 #define r_pkt rbuf.pkt 94 95 #ifdef HAVE_DROPROOT 96 int droproot; /* intres imports these */ 97 int root_dropped; 98 #endif 99 u_long current_time; /* libntp/authkeys.c */ 100 101 void open_sockets(void); 102 void handle_lookup(const char *name, int flags); 103 void sntp_addremove_fd(int fd, int is_pipe, int remove_it); 104 void worker_timeout(evutil_socket_t, short, void *); 105 void worker_resp_cb(evutil_socket_t, short, void *); 106 void sntp_name_resolved(int, int, void *, const char *, const char *, 107 const struct addrinfo *, 108 const struct addrinfo *); 109 void queue_xmt(SOCKET sock, struct dns_ctx *dctx, sent_pkt *spkt, 110 u_int xmt_delay); 111 void xmt_timer_cb(evutil_socket_t, short, void *ptr); 112 void xmt(xmt_ctx *xctx); 113 int check_kod(const struct addrinfo *ai); 114 void timeout_query(sent_pkt *); 115 void timeout_queries(void); 116 void sock_cb(evutil_socket_t, short, void *); 117 void check_exit_conditions(void); 118 void sntp_libevent_log_cb(int, const char *); 119 void set_li_vn_mode(struct pkt *spkt, char leap, char version, char mode); 120 int set_time(double offset); 121 void dec_pending_ntp(const char *, sockaddr_u *); 122 int libevent_version_ok(void); 123 int gettimeofday_cached(struct event_base *b, struct timeval *tv); 124 125 126 /* 127 * The actual main function. 128 */ 129 int 130 sntp_main ( 131 int argc, 132 char **argv, 133 const char *sntpVersion 134 ) 135 { 136 int i; 137 int exitcode; 138 int optct; 139 struct event_config * evcfg; 140 141 /* Initialize logging system - sets up progname */ 142 sntp_init_logging(argv[0]); 143 144 if (!libevent_version_ok()) 145 exit(EX_SOFTWARE); 146 147 init_lib(); 148 init_auth(); 149 150 optct = ntpOptionProcess(&sntpOptions, argc, argv); 151 argc -= optct; 152 argv += optct; 153 154 155 debug = OPT_VALUE_SET_DEBUG_LEVEL; 156 157 TRACE(2, ("init_lib() done, %s%s\n", 158 (ipv4_works) 159 ? "ipv4_works " 160 : "", 161 (ipv6_works) 162 ? "ipv6_works " 163 : "")); 164 ntpver = OPT_VALUE_NTPVERSION; 165 steplimit = OPT_VALUE_STEPLIMIT / 1e3; 166 gap.tv_usec = max(0, OPT_VALUE_GAP * 1000); 167 gap.tv_usec = min(gap.tv_usec, 999999); 168 169 if (HAVE_OPT(LOGFILE)) 170 open_logfile(OPT_ARG(LOGFILE)); 171 172 msyslog(LOG_INFO, "%s", sntpVersion); 173 174 if (0 == argc && !HAVE_OPT(BROADCAST) && !HAVE_OPT(CONCURRENT)) { 175 printf("%s: Must supply at least one of -b hostname, -c hostname, or hostname.\n", 176 progname); 177 exit(EX_USAGE); 178 } 179 180 181 /* 182 ** Eventually, we probably want: 183 ** - separate bcst and ucst timeouts (why?) 184 ** - multiple --timeout values in the commandline 185 */ 186 187 response_timeout = OPT_VALUE_TIMEOUT; 188 response_tv.tv_sec = response_timeout; 189 response_tv.tv_usec = 0; 190 191 /* IPv6 available? */ 192 if (isc_net_probeipv6() != ISC_R_SUCCESS) { 193 ai_fam_pref = AF_INET; 194 TRACE(1, ("No ipv6 support available, forcing ipv4\n")); 195 } else { 196 /* Check for options -4 and -6 */ 197 if (HAVE_OPT(IPV4)) 198 ai_fam_pref = AF_INET; 199 else if (HAVE_OPT(IPV6)) 200 ai_fam_pref = AF_INET6; 201 } 202 203 /* TODO: Parse config file if declared */ 204 205 /* 206 ** Init the KOD system. 207 ** For embedded systems with no writable filesystem, 208 ** -K /dev/null can be used to disable KoD storage. 209 */ 210 kod_init_kod_db(OPT_ARG(KOD), FALSE); 211 212 // HMS: Should we use arg-defalt for this too? 213 if (HAVE_OPT(KEYFILE)) 214 auth_init(OPT_ARG(KEYFILE), &keys); 215 216 /* 217 ** Considering employing a variable that prevents functions of doing 218 ** anything until everything is initialized properly 219 ** 220 ** HMS: What exactly does the above mean? 221 */ 222 event_set_log_callback(&sntp_libevent_log_cb); 223 if (debug > 0) 224 event_enable_debug_mode(); 225 #ifdef WORK_THREAD 226 evthread_use_pthreads(); 227 /* we use libevent from main thread only, locks should be academic */ 228 if (debug > 0) 229 evthread_enable_lock_debuging(); 230 #endif 231 evcfg = event_config_new(); 232 if (NULL == evcfg) { 233 printf("%s: event_config_new() failed!\n", progname); 234 return -1; 235 } 236 #ifndef HAVE_SOCKETPAIR 237 event_config_require_features(evcfg, EV_FEATURE_FDS); 238 #endif 239 /* all libevent calls are from main thread */ 240 /* event_config_set_flag(evcfg, EVENT_BASE_FLAG_NOLOCK); */ 241 base = event_base_new_with_config(evcfg); 242 event_config_free(evcfg); 243 if (NULL == base) { 244 printf("%s: event_base_new() failed!\n", progname); 245 return -1; 246 } 247 248 /* wire into intres resolver */ 249 worker_per_query = TRUE; 250 addremove_io_fd = &sntp_addremove_fd; 251 252 open_sockets(); 253 254 if (HAVE_OPT(BROADCAST)) { 255 int cn = STACKCT_OPT( BROADCAST ); 256 const char ** cp = STACKLST_OPT( BROADCAST ); 257 258 while (cn-- > 0) { 259 handle_lookup(*cp, CTX_BCST); 260 cp++; 261 } 262 } 263 264 if (HAVE_OPT(CONCURRENT)) { 265 int cn = STACKCT_OPT( CONCURRENT ); 266 const char ** cp = STACKLST_OPT( CONCURRENT ); 267 268 while (cn-- > 0) { 269 handle_lookup(*cp, CTX_UCST | CTX_CONC); 270 cp++; 271 } 272 } 273 274 for (i = 0; i < argc; ++i) 275 handle_lookup(argv[i], CTX_UCST); 276 277 gettimeofday_cached(base, &start_tv); 278 event_base_dispatch(base); 279 event_base_free(base); 280 281 if (!time_adjusted && 282 (ENABLED_OPT(STEP) || ENABLED_OPT(SLEW))) 283 exitcode = 1; 284 else 285 exitcode = 0; 286 287 return exitcode; 288 } 289 290 291 /* 292 ** open sockets and make them non-blocking 293 */ 294 void 295 open_sockets( 296 void 297 ) 298 { 299 sockaddr_u name; 300 301 if (-1 == sock4) { 302 sock4 = socket(PF_INET, SOCK_DGRAM, 0); 303 if (-1 == sock4) { 304 /* error getting a socket */ 305 msyslog(LOG_ERR, "open_sockets: socket(PF_INET) failed: %m"); 306 exit(1); 307 } 308 /* Make it non-blocking */ 309 make_socket_nonblocking(sock4); 310 311 /* Let's try using a wildcard... */ 312 ZERO(name); 313 AF(&name) = AF_INET; 314 SET_ADDR4N(&name, INADDR_ANY); 315 SET_PORT(&name, (HAVE_OPT(USERESERVEDPORT) ? 123 : 0)); 316 317 if (-1 == bind(sock4, &name.sa, 318 SOCKLEN(&name))) { 319 msyslog(LOG_ERR, "open_sockets: bind(sock4) failed: %m"); 320 exit(1); 321 } 322 323 /* Register an NTP callback for recv/timeout */ 324 ev_sock4 = event_new(base, sock4, 325 EV_TIMEOUT | EV_READ | EV_PERSIST, 326 &sock_cb, NULL); 327 if (NULL == ev_sock4) { 328 msyslog(LOG_ERR, 329 "open_sockets: event_new(base, sock4) failed!"); 330 } else { 331 event_add(ev_sock4, &wakeup_tv); 332 } 333 } 334 335 /* We may not always have IPv6... */ 336 if (-1 == sock6 && ipv6_works) { 337 sock6 = socket(PF_INET6, SOCK_DGRAM, 0); 338 if (-1 == sock6 && ipv6_works) { 339 /* error getting a socket */ 340 msyslog(LOG_ERR, "open_sockets: socket(PF_INET6) failed: %m"); 341 exit(1); 342 } 343 /* Make it non-blocking */ 344 make_socket_nonblocking(sock6); 345 346 /* Let's try using a wildcard... */ 347 ZERO(name); 348 AF(&name) = AF_INET6; 349 SET_ADDR6N(&name, in6addr_any); 350 SET_PORT(&name, (HAVE_OPT(USERESERVEDPORT) ? 123 : 0)); 351 352 if (-1 == bind(sock6, &name.sa, 353 SOCKLEN(&name))) { 354 msyslog(LOG_ERR, "open_sockets: bind(sock6) failed: %m"); 355 exit(1); 356 } 357 /* Register an NTP callback for recv/timeout */ 358 ev_sock6 = event_new(base, sock6, 359 EV_TIMEOUT | EV_READ | EV_PERSIST, 360 &sock_cb, NULL); 361 if (NULL == ev_sock6) { 362 msyslog(LOG_ERR, 363 "open_sockets: event_new(base, sock6) failed!"); 364 } else { 365 event_add(ev_sock6, &wakeup_tv); 366 } 367 } 368 369 return; 370 } 371 372 373 /* 374 ** handle_lookup 375 */ 376 void 377 handle_lookup( 378 const char *name, 379 int flags 380 ) 381 { 382 struct addrinfo hints; /* Local copy is OK */ 383 struct dns_ctx *ctx; 384 long l; 385 char * name_copy; 386 size_t name_sz; 387 size_t octets; 388 389 TRACE(1, ("handle_lookup(%s,%#x)\n", name, flags)); 390 391 ZERO(hints); 392 hints.ai_family = ai_fam_pref; 393 hints.ai_flags = AI_CANONNAME | Z_AI_NUMERICSERV; 394 /* 395 ** Unless we specify a socktype, we'll get at least two 396 ** entries for each address: one for TCP and one for 397 ** UDP. That's not what we want. 398 */ 399 hints.ai_socktype = SOCK_DGRAM; 400 hints.ai_protocol = IPPROTO_UDP; 401 402 name_sz = 1 + strlen(name); 403 octets = sizeof(*ctx) + name_sz; // Space for a ctx and the name 404 ctx = emalloc_zero(octets); // ctx at ctx[0] 405 name_copy = (char *)(ctx + 1); // Put the name at ctx[1] 406 memcpy(name_copy, name, name_sz); // copy the name to ctx[1] 407 ctx->name = name_copy; // point to it... 408 ctx->flags = flags; 409 ctx->timeout = response_tv; 410 411 /* The following should arguably be passed in... */ 412 if (ENABLED_OPT(AUTHENTICATION) && 413 atoint(OPT_ARG(AUTHENTICATION), &l)) { 414 ctx->key_id = l; 415 get_key(ctx->key_id, &ctx->key); 416 } else { 417 ctx->key_id = -1; 418 ctx->key = NULL; 419 } 420 421 ++n_pending_dns; 422 getaddrinfo_sometime(name, "123", &hints, 0, 423 &sntp_name_resolved, ctx); 424 } 425 426 427 /* 428 ** DNS Callback: 429 ** - For each IP: 430 ** - - open a socket 431 ** - - increment n_pending_ntp 432 ** - - send a request if this is a Unicast callback 433 ** - - queue wait for response 434 ** - decrement n_pending_dns 435 */ 436 void 437 sntp_name_resolved( 438 int rescode, 439 int gai_errno, 440 void * context, 441 const char * name, 442 const char * service, 443 const struct addrinfo * hints, 444 const struct addrinfo * addr 445 ) 446 { 447 struct dns_ctx * dctx; 448 sent_pkt * spkt; 449 const struct addrinfo * ai; 450 SOCKET sock; 451 u_int xmt_delay_v4; 452 u_int xmt_delay_v6; 453 u_int xmt_delay; 454 size_t octets; 455 456 xmt_delay_v4 = 0; 457 xmt_delay_v6 = 0; 458 dctx = context; 459 if (rescode) { 460 #ifdef EAI_SYSTEM 461 if (EAI_SYSTEM == rescode) { 462 errno = gai_errno; 463 mfprintf(stderr, "%s lookup error %m\n", 464 dctx->name); 465 } else 466 #endif 467 fprintf(stderr, "%s lookup error %s\n", 468 dctx->name, gai_strerror(rescode)); 469 } else { 470 TRACE(3, ("%s [%s]\n", dctx->name, 471 (addr->ai_canonname != NULL) 472 ? addr->ai_canonname 473 : "")); 474 475 for (ai = addr; ai != NULL; ai = ai->ai_next) { 476 477 if (check_kod(ai)) 478 continue; 479 480 switch (ai->ai_family) { 481 482 case AF_INET: 483 sock = sock4; 484 xmt_delay = xmt_delay_v4; 485 xmt_delay_v4++; 486 break; 487 488 case AF_INET6: 489 if (!ipv6_works) 490 continue; 491 492 sock = sock6; 493 xmt_delay = xmt_delay_v6; 494 xmt_delay_v6++; 495 break; 496 497 default: 498 msyslog(LOG_ERR, "sntp_name_resolved: unexpected ai_family: %d", 499 ai->ai_family); 500 exit(1); 501 break; 502 } 503 504 /* 505 ** We're waiting for a response for either unicast 506 ** or broadcast, so... 507 */ 508 ++n_pending_ntp; 509 510 /* If this is for a unicast IP, queue a request */ 511 if (dctx->flags & CTX_UCST) { 512 spkt = emalloc_zero(sizeof(*spkt)); 513 spkt->dctx = dctx; 514 octets = min(ai->ai_addrlen, sizeof(spkt->addr)); 515 memcpy(&spkt->addr, ai->ai_addr, octets); 516 queue_xmt(sock, dctx, spkt, xmt_delay); 517 } 518 } 519 } 520 /* n_pending_dns really should be >0 here... */ 521 --n_pending_dns; 522 check_exit_conditions(); 523 } 524 525 526 /* 527 ** queue_xmt 528 */ 529 void 530 queue_xmt( 531 SOCKET sock, 532 struct dns_ctx * dctx, 533 sent_pkt * spkt, 534 u_int xmt_delay 535 ) 536 { 537 sockaddr_u * dest; 538 sent_pkt ** pkt_listp; 539 sent_pkt * match; 540 xmt_ctx * xctx; 541 struct timeval start_cb; 542 struct timeval delay; 543 544 dest = &spkt->addr; 545 if (IS_IPV6(dest)) 546 pkt_listp = &v6_pkts_list; 547 else 548 pkt_listp = &v4_pkts_list; 549 550 /* reject attempts to add address already listed */ 551 for (match = *pkt_listp; match != NULL; match = match->link) { 552 if (ADDR_PORT_EQ(&spkt->addr, &match->addr)) { 553 if (strcasecmp(spkt->dctx->name, 554 match->dctx->name)) 555 printf("%s %s duplicate address from %s ignored.\n", 556 sptoa(&match->addr), 557 match->dctx->name, 558 spkt->dctx->name); 559 else 560 printf("%s %s, duplicate address ignored.\n", 561 sptoa(&match->addr), 562 match->dctx->name); 563 dec_pending_ntp(spkt->dctx->name, &spkt->addr); 564 free(spkt); 565 return; 566 } 567 } 568 569 LINK_SLIST(*pkt_listp, spkt, link); 570 571 xctx = emalloc_zero(sizeof(*xctx)); 572 xctx->sock = sock; 573 xctx->spkt = spkt; 574 gettimeofday_cached(base, &start_cb); 575 xctx->sched = start_cb.tv_sec + (2 * xmt_delay); 576 577 LINK_SORT_SLIST(xmt_q, xctx, (xctx->sched < L_S_S_CUR()->sched), 578 link, xmt_ctx); 579 if (xmt_q == xctx) { 580 /* 581 * The new entry is the first scheduled. The timer is 582 * either not active or is set for the second xmt 583 * context in xmt_q. 584 */ 585 if (NULL == ev_xmt_timer) 586 ev_xmt_timer = event_new(base, INVALID_SOCKET, 587 EV_TIMEOUT, 588 &xmt_timer_cb, NULL); 589 if (NULL == ev_xmt_timer) { 590 msyslog(LOG_ERR, 591 "queue_xmt: event_new(base, -1, EV_TIMEOUT) failed!"); 592 exit(1); 593 } 594 ZERO(delay); 595 if (xctx->sched > start_cb.tv_sec) 596 delay.tv_sec = xctx->sched - start_cb.tv_sec; 597 event_add(ev_xmt_timer, &delay); 598 TRACE(2, ("queue_xmt: xmt timer for %u usec\n", 599 (u_int)delay.tv_usec)); 600 } 601 } 602 603 604 /* 605 ** xmt_timer_cb 606 */ 607 void 608 xmt_timer_cb( 609 evutil_socket_t fd, 610 short what, 611 void * ctx 612 ) 613 { 614 struct timeval start_cb; 615 struct timeval delay; 616 xmt_ctx * x; 617 618 UNUSED_ARG(fd); 619 UNUSED_ARG(ctx); 620 DEBUG_INSIST(EV_TIMEOUT == what); 621 622 if (NULL == xmt_q || shutting_down) 623 return; 624 gettimeofday_cached(base, &start_cb); 625 if (xmt_q->sched <= start_cb.tv_sec) { 626 UNLINK_HEAD_SLIST(x, xmt_q, link); 627 TRACE(2, ("xmt_timer_cb: at .%6.6u -> %s\n", 628 (u_int)start_cb.tv_usec, stoa(&x->spkt->addr))); 629 xmt(x); 630 free(x); 631 if (NULL == xmt_q) 632 return; 633 } 634 if (xmt_q->sched <= start_cb.tv_sec) { 635 event_add(ev_xmt_timer, &gap); 636 TRACE(2, ("xmt_timer_cb: at .%6.6u gap %6.6u\n", 637 (u_int)start_cb.tv_usec, 638 (u_int)gap.tv_usec)); 639 } else { 640 delay.tv_sec = xmt_q->sched - start_cb.tv_sec; 641 delay.tv_usec = 0; 642 event_add(ev_xmt_timer, &delay); 643 TRACE(2, ("xmt_timer_cb: at .%6.6u next %ld seconds\n", 644 (u_int)start_cb.tv_usec, 645 (long)delay.tv_sec)); 646 } 647 } 648 649 650 /* 651 ** xmt() 652 */ 653 void 654 xmt( 655 xmt_ctx * xctx 656 ) 657 { 658 SOCKET sock = xctx->sock; 659 struct dns_ctx *dctx = xctx->spkt->dctx; 660 sent_pkt * spkt = xctx->spkt; 661 sockaddr_u * dst = &spkt->addr; 662 struct timeval tv_xmt; 663 struct pkt x_pkt; 664 size_t pkt_len; 665 int sent; 666 667 if (0 != gettimeofday(&tv_xmt, NULL)) { 668 msyslog(LOG_ERR, 669 "xmt: gettimeofday() failed: %m"); 670 exit(1); 671 } 672 tv_xmt.tv_sec += JAN_1970; 673 674 pkt_len = generate_pkt(&x_pkt, &tv_xmt, dctx->key_id, 675 dctx->key); 676 677 sent = sendpkt(sock, dst, &x_pkt, pkt_len); 678 if (sent) { 679 /* Save the packet we sent... */ 680 memcpy(&spkt->x_pkt, &x_pkt, min(sizeof(spkt->x_pkt), 681 pkt_len)); 682 spkt->stime = tv_xmt.tv_sec - JAN_1970; 683 684 TRACE(2, ("xmt: %lx.%6.6u %s %s\n", (u_long)tv_xmt.tv_sec, 685 (u_int)tv_xmt.tv_usec, dctx->name, stoa(dst))); 686 } else { 687 dec_pending_ntp(dctx->name, dst); 688 } 689 690 return; 691 } 692 693 694 /* 695 * timeout_queries() -- give up on unrequited NTP queries 696 */ 697 void 698 timeout_queries(void) 699 { 700 struct timeval start_cb; 701 u_int idx; 702 sent_pkt * head; 703 sent_pkt * spkt; 704 sent_pkt * spkt_next; 705 long age; 706 int didsomething = 0; 707 708 TRACE(3, ("timeout_queries: called to check %u items\n", 709 (unsigned)COUNTOF(fam_listheads))); 710 711 gettimeofday_cached(base, &start_cb); 712 for (idx = 0; idx < COUNTOF(fam_listheads); idx++) { 713 head = fam_listheads[idx]; 714 for (spkt = head; spkt != NULL; spkt = spkt_next) { 715 char xcst; 716 717 didsomething = 1; 718 switch (spkt->dctx->flags & CTX_xCST) { 719 case CTX_BCST: 720 xcst = 'B'; 721 break; 722 723 case CTX_UCST: 724 xcst = 'U'; 725 break; 726 727 default: 728 INSIST(!"spkt->dctx->flags neither UCST nor BCST"); 729 break; 730 } 731 732 spkt_next = spkt->link; 733 if (0 == spkt->stime || spkt->done) 734 continue; 735 age = start_cb.tv_sec - spkt->stime; 736 TRACE(3, ("%s %s %cCST age %ld\n", 737 stoa(&spkt->addr), 738 spkt->dctx->name, xcst, age)); 739 if (age > response_timeout) 740 timeout_query(spkt); 741 } 742 } 743 // Do we care about didsomething? 744 TRACE(3, ("timeout_queries: didsomething is %d, age is %ld\n", 745 didsomething, (long) (start_cb.tv_sec - start_tv.tv_sec))); 746 if (start_cb.tv_sec - start_tv.tv_sec > response_timeout) { 747 TRACE(3, ("timeout_queries: bail!\n")); 748 event_base_loopexit(base, NULL); 749 shutting_down = TRUE; 750 } 751 } 752 753 754 void dec_pending_ntp( 755 const char * name, 756 sockaddr_u * server 757 ) 758 { 759 if (n_pending_ntp > 0) { 760 --n_pending_ntp; 761 check_exit_conditions(); 762 } else { 763 INSIST(0 == n_pending_ntp); 764 TRACE(1, ("n_pending_ntp was zero before decrement for %s\n", 765 hostnameaddr(name, server))); 766 } 767 } 768 769 770 void timeout_query( 771 sent_pkt * spkt 772 ) 773 { 774 sockaddr_u * server; 775 char xcst; 776 777 778 switch (spkt->dctx->flags & CTX_xCST) { 779 case CTX_BCST: 780 xcst = 'B'; 781 break; 782 783 case CTX_UCST: 784 xcst = 'U'; 785 break; 786 787 default: 788 INSIST(!"spkt->dctx->flags neither UCST nor BCST"); 789 break; 790 } 791 spkt->done = TRUE; 792 server = &spkt->addr; 793 msyslog(LOG_INFO, "%s no %cCST response after %d seconds", 794 hostnameaddr(spkt->dctx->name, server), xcst, 795 response_timeout); 796 dec_pending_ntp(spkt->dctx->name, server); 797 return; 798 } 799 800 801 /* 802 ** check_kod 803 */ 804 int 805 check_kod( 806 const struct addrinfo * ai 807 ) 808 { 809 char *hostname; 810 struct kod_entry *reason; 811 812 /* Is there a KoD on file for this address? */ 813 hostname = addrinfo_to_str(ai); 814 TRACE(2, ("check_kod: checking <%s>\n", hostname)); 815 if (search_entry(hostname, &reason)) { 816 printf("prior KoD for %s, skipping.\n", 817 hostname); 818 free(reason); 819 free(hostname); 820 821 return 1; 822 } 823 free(hostname); 824 825 return 0; 826 } 827 828 829 /* 830 ** Socket readable/timeout Callback: 831 ** Read in the packet 832 ** Unicast: 833 ** - close socket 834 ** - decrement n_pending_ntp 835 ** - If packet is good, set the time and "exit" 836 ** Broadcast: 837 ** - If packet is good, set the time and "exit" 838 */ 839 void 840 sock_cb( 841 evutil_socket_t fd, 842 short what, 843 void *ptr 844 ) 845 { 846 sockaddr_u sender; 847 sockaddr_u * psau; 848 sent_pkt ** p_pktlist; 849 sent_pkt * spkt; 850 int rpktl; 851 int rc; 852 853 INSIST(sock4 == fd || sock6 == fd); 854 855 TRACE(3, ("sock_cb: event on sock%s:%s%s%s%s\n", 856 (fd == sock6) 857 ? "6" 858 : "4", 859 (what & EV_TIMEOUT) ? " timeout" : "", 860 (what & EV_READ) ? " read" : "", 861 (what & EV_WRITE) ? " write" : "", 862 (what & EV_SIGNAL) ? " signal" : "")); 863 864 if (!(EV_READ & what)) { 865 if (EV_TIMEOUT & what) 866 timeout_queries(); 867 868 return; 869 } 870 871 /* Read in the packet */ 872 rpktl = recvdata(fd, &sender, &rbuf, sizeof(rbuf)); 873 if (rpktl < 0) { 874 msyslog(LOG_DEBUG, "recvfrom error %m"); 875 return; 876 } 877 878 if (sock6 == fd) 879 p_pktlist = &v6_pkts_list; 880 else 881 p_pktlist = &v4_pkts_list; 882 883 for (spkt = *p_pktlist; spkt != NULL; spkt = spkt->link) { 884 psau = &spkt->addr; 885 if (SOCK_EQ(&sender, psau)) 886 break; 887 } 888 if (NULL == spkt) { 889 msyslog(LOG_WARNING, 890 "Packet from unexpected source %s dropped", 891 sptoa(&sender)); 892 return; 893 } 894 895 TRACE(1, ("sock_cb: %s %s\n", spkt->dctx->name, 896 sptoa(&sender))); 897 898 rpktl = process_pkt(&r_pkt, &sender, rpktl, MODE_SERVER, 899 &spkt->x_pkt, "sock_cb"); 900 901 TRACE(2, ("sock_cb: process_pkt returned %d\n", rpktl)); 902 903 /* If this is a Unicast packet, one down ... */ 904 if (!spkt->done && (CTX_UCST & spkt->dctx->flags)) { 905 dec_pending_ntp(spkt->dctx->name, &spkt->addr); 906 spkt->done = TRUE; 907 } 908 909 910 /* If the packet is good, set the time and we're all done */ 911 rc = handle_pkt(rpktl, &r_pkt, &spkt->addr, spkt->dctx->name); 912 if (0 != rc) 913 TRACE(1, ("sock_cb: handle_pkt() returned %d\n", rc)); 914 check_exit_conditions(); 915 } 916 917 918 /* 919 * check_exit_conditions() 920 * 921 * If sntp has a reply, ask the event loop to stop after this round of 922 * callbacks, unless --wait was used. 923 */ 924 void 925 check_exit_conditions(void) 926 { 927 if ((0 == n_pending_ntp && 0 == n_pending_dns) || 928 (time_derived && !HAVE_OPT(WAIT))) { 929 event_base_loopexit(base, NULL); 930 shutting_down = TRUE; 931 } else { 932 TRACE(2, ("%d NTP and %d name queries pending\n", 933 n_pending_ntp, n_pending_dns)); 934 } 935 } 936 937 938 /* 939 * sntp_addremove_fd() is invoked by the intres blocking worker code 940 * to read from a pipe, or to stop same. 941 */ 942 void sntp_addremove_fd( 943 int fd, 944 int is_pipe, 945 int remove_it 946 ) 947 { 948 u_int idx; 949 blocking_child *c; 950 struct event * ev; 951 952 #ifdef HAVE_SOCKETPAIR 953 if (is_pipe) { 954 /* sntp only asks for EV_FEATURE_FDS without HAVE_SOCKETPAIR */ 955 msyslog(LOG_ERR, "fatal: pipes not supported on systems with socketpair()"); 956 exit(1); 957 } 958 #endif 959 960 c = NULL; 961 for (idx = 0; idx < blocking_children_alloc; idx++) { 962 c = blocking_children[idx]; 963 if (NULL == c) 964 continue; 965 if (fd == c->resp_read_pipe) 966 break; 967 } 968 if (idx == blocking_children_alloc) 969 return; 970 971 if (remove_it) { 972 ev = c->resp_read_ctx; 973 c->resp_read_ctx = NULL; 974 event_del(ev); 975 event_free(ev); 976 977 return; 978 } 979 980 ev = event_new(base, fd, EV_READ | EV_PERSIST, 981 &worker_resp_cb, c); 982 if (NULL == ev) { 983 msyslog(LOG_ERR, 984 "sntp_addremove_fd: event_new(base, fd) failed!"); 985 return; 986 } 987 c->resp_read_ctx = ev; 988 event_add(ev, NULL); 989 } 990 991 992 /* called by forked intres child to close open descriptors */ 993 #ifdef WORK_FORK 994 void 995 kill_asyncio( 996 int startfd 997 ) 998 { 999 if (INVALID_SOCKET != sock4) { 1000 closesocket(sock4); 1001 sock4 = INVALID_SOCKET; 1002 } 1003 if (INVALID_SOCKET != sock6) { 1004 closesocket(sock6); 1005 sock6 = INVALID_SOCKET; 1006 } 1007 if (INVALID_SOCKET != bsock4) { 1008 closesocket(sock4); 1009 sock4 = INVALID_SOCKET; 1010 } 1011 if (INVALID_SOCKET != bsock6) { 1012 closesocket(sock6); 1013 sock6 = INVALID_SOCKET; 1014 } 1015 } 1016 #endif 1017 1018 1019 /* 1020 * worker_resp_cb() is invoked when resp_read_pipe is readable. 1021 */ 1022 void 1023 worker_resp_cb( 1024 evutil_socket_t fd, 1025 short what, 1026 void * ctx /* blocking_child * */ 1027 ) 1028 { 1029 blocking_child * c; 1030 1031 DEBUG_INSIST(EV_READ & what); 1032 c = ctx; 1033 DEBUG_INSIST(fd == c->resp_read_pipe); 1034 process_blocking_resp(c); 1035 } 1036 1037 1038 /* 1039 * intres_timeout_req(s) is invoked in the parent to schedule an idle 1040 * timeout to fire in s seconds, if not reset earlier by a call to 1041 * intres_timeout_req(0), which clears any pending timeout. When the 1042 * timeout expires, worker_idle_timer_fired() is invoked (again, in the 1043 * parent). 1044 * 1045 * sntp and ntpd each provide implementations adapted to their timers. 1046 */ 1047 void 1048 intres_timeout_req( 1049 u_int seconds /* 0 cancels */ 1050 ) 1051 { 1052 struct timeval tv_to; 1053 1054 if (NULL == ev_worker_timeout) { 1055 ev_worker_timeout = event_new(base, -1, 1056 EV_TIMEOUT | EV_PERSIST, 1057 &worker_timeout, NULL); 1058 DEBUG_INSIST(NULL != ev_worker_timeout); 1059 } else { 1060 event_del(ev_worker_timeout); 1061 } 1062 if (0 == seconds) 1063 return; 1064 tv_to.tv_sec = seconds; 1065 tv_to.tv_usec = 0; 1066 event_add(ev_worker_timeout, &tv_to); 1067 } 1068 1069 1070 void 1071 worker_timeout( 1072 evutil_socket_t fd, 1073 short what, 1074 void * ctx 1075 ) 1076 { 1077 UNUSED_ARG(fd); 1078 UNUSED_ARG(ctx); 1079 1080 DEBUG_REQUIRE(EV_TIMEOUT & what); 1081 worker_idle_timer_fired(); 1082 } 1083 1084 1085 void 1086 sntp_libevent_log_cb( 1087 int severity, 1088 const char * msg 1089 ) 1090 { 1091 int level; 1092 1093 switch (severity) { 1094 1095 default: 1096 case _EVENT_LOG_DEBUG: 1097 level = LOG_DEBUG; 1098 break; 1099 1100 case _EVENT_LOG_MSG: 1101 level = LOG_NOTICE; 1102 break; 1103 1104 case _EVENT_LOG_WARN: 1105 level = LOG_WARNING; 1106 break; 1107 1108 case _EVENT_LOG_ERR: 1109 level = LOG_ERR; 1110 break; 1111 } 1112 1113 msyslog(level, "%s", msg); 1114 } 1115 1116 1117 int 1118 generate_pkt ( 1119 struct pkt *x_pkt, 1120 const struct timeval *tv_xmt, 1121 int key_id, 1122 struct key *pkt_key 1123 ) 1124 { 1125 l_fp xmt_fp; 1126 int pkt_len; 1127 int mac_size; 1128 1129 pkt_len = LEN_PKT_NOMAC; 1130 ZERO(*x_pkt); 1131 TVTOTS(tv_xmt, &xmt_fp); 1132 HTONL_FP(&xmt_fp, &x_pkt->xmt); 1133 x_pkt->stratum = STRATUM_TO_PKT(STRATUM_UNSPEC); 1134 x_pkt->ppoll = 8; 1135 /* FIXME! Modus broadcast + adr. check -> bdr. pkt */ 1136 set_li_vn_mode(x_pkt, LEAP_NOTINSYNC, ntpver, 3); 1137 if (pkt_key != NULL) { 1138 x_pkt->exten[0] = htonl(key_id); 1139 mac_size = 20; /* max room for MAC */ 1140 mac_size = make_mac((char *)x_pkt, pkt_len, mac_size, 1141 pkt_key, (char *)&x_pkt->exten[1]); 1142 if (mac_size > 0) 1143 pkt_len += mac_size + 4; 1144 } 1145 return pkt_len; 1146 } 1147 1148 1149 int 1150 handle_pkt( 1151 int rpktl, 1152 struct pkt * rpkt, 1153 sockaddr_u * host, 1154 const char * hostname 1155 ) 1156 { 1157 char disptxt[32]; 1158 const char * addrtxt; 1159 struct timeval tv_dst; 1160 int cnt; 1161 int sw_case; 1162 int digits; 1163 int stratum; 1164 char * ref; 1165 char * ts_str; 1166 const char * leaptxt; 1167 double offset; 1168 double precision; 1169 double synch_distance; 1170 char * p_SNTP_PRETEND_TIME; 1171 time_t pretend_time; 1172 #if SIZEOF_TIME_T == 8 1173 long long ll; 1174 #else 1175 long l; 1176 #endif 1177 1178 ts_str = NULL; 1179 1180 if (rpktl > 0) 1181 sw_case = 1; 1182 else 1183 sw_case = rpktl; 1184 1185 switch (sw_case) { 1186 1187 case SERVER_UNUSEABLE: 1188 return -1; 1189 break; 1190 1191 case PACKET_UNUSEABLE: 1192 break; 1193 1194 case SERVER_AUTH_FAIL: 1195 break; 1196 1197 case KOD_DEMOBILIZE: 1198 /* Received a DENY or RESTR KOD packet */ 1199 addrtxt = stoa(host); 1200 ref = (char *)&rpkt->refid; 1201 add_entry(addrtxt, ref); 1202 msyslog(LOG_WARNING, "KOD code %c%c%c%c from %s %s", 1203 ref[0], ref[1], ref[2], ref[3], addrtxt, hostname); 1204 break; 1205 1206 case KOD_RATE: 1207 /* 1208 ** Hmm... 1209 ** We should probably call add_entry() with an 1210 ** expiration timestamp of several seconds in the future, 1211 ** and back-off even more if we get more RATE responses. 1212 */ 1213 break; 1214 1215 case 1: 1216 TRACE(3, ("handle_pkt: %d bytes from %s %s\n", 1217 rpktl, stoa(host), hostname)); 1218 1219 gettimeofday_cached(base, &tv_dst); 1220 1221 p_SNTP_PRETEND_TIME = getenv("SNTP_PRETEND_TIME"); 1222 if (p_SNTP_PRETEND_TIME) { 1223 pretend_time = 0; 1224 #if SIZEOF_TIME_T == 4 1225 if (1 == sscanf(p_SNTP_PRETEND_TIME, "%ld", &l)) 1226 pretend_time = (time_t)l; 1227 #elif SIZEOF_TIME_T == 8 1228 if (1 == sscanf(p_SNTP_PRETEND_TIME, "%lld", &ll)) 1229 pretend_time = (time_t)ll; 1230 #else 1231 # include "GRONK: unexpected value for SIZEOF_TIME_T" 1232 #endif 1233 if (0 != pretend_time) 1234 tv_dst.tv_sec = pretend_time; 1235 } 1236 1237 offset_calculation(rpkt, rpktl, &tv_dst, &offset, 1238 &precision, &synch_distance); 1239 time_derived = TRUE; 1240 1241 for (digits = 0; (precision *= 10.) < 1.; ++digits) 1242 /* empty */ ; 1243 if (digits > 6) 1244 digits = 6; 1245 1246 ts_str = tv_to_str(&tv_dst); 1247 stratum = rpkt->stratum; 1248 if (0 == stratum) 1249 stratum = 16; 1250 1251 if (synch_distance > 0.) { 1252 cnt = snprintf(disptxt, sizeof(disptxt), 1253 " +/- %f", synch_distance); 1254 if ((size_t)cnt >= sizeof(disptxt)) 1255 snprintf(disptxt, sizeof(disptxt), 1256 "ERROR %d >= %d", cnt, 1257 (int)sizeof(disptxt)); 1258 } else { 1259 disptxt[0] = '\0'; 1260 } 1261 1262 switch (PKT_LEAP(rpkt->li_vn_mode)) { 1263 case LEAP_NOWARNING: 1264 leaptxt = "no-leap"; 1265 break; 1266 case LEAP_ADDSECOND: 1267 leaptxt = "add-leap"; 1268 break; 1269 case LEAP_DELSECOND: 1270 leaptxt = "del-leap"; 1271 break; 1272 case LEAP_NOTINSYNC: 1273 leaptxt = "unsync"; 1274 break; 1275 default: 1276 leaptxt = "LEAP-ERROR"; 1277 break; 1278 } 1279 1280 msyslog(LOG_INFO, "%s %+.*f%s %s s%d %s%s", ts_str, 1281 digits, offset, disptxt, 1282 hostnameaddr(hostname, host), stratum, 1283 leaptxt, 1284 (time_adjusted) 1285 ? " [excess]" 1286 : ""); 1287 free(ts_str); 1288 1289 if (p_SNTP_PRETEND_TIME) 1290 return 0; 1291 1292 if (!time_adjusted && 1293 (ENABLED_OPT(STEP) || ENABLED_OPT(SLEW))) 1294 return set_time(offset); 1295 1296 return EX_OK; 1297 } 1298 1299 return 1; 1300 } 1301 1302 1303 void 1304 offset_calculation( 1305 struct pkt *rpkt, 1306 int rpktl, 1307 struct timeval *tv_dst, 1308 double *offset, 1309 double *precision, 1310 double *synch_distance 1311 ) 1312 { 1313 l_fp p_rec, p_xmt, p_ref, p_org, tmp, dst; 1314 u_fp p_rdly, p_rdsp; 1315 double t21, t34, delta; 1316 1317 /* Convert timestamps from network to host byte order */ 1318 p_rdly = NTOHS_FP(rpkt->rootdelay); 1319 p_rdsp = NTOHS_FP(rpkt->rootdisp); 1320 NTOHL_FP(&rpkt->reftime, &p_ref); 1321 NTOHL_FP(&rpkt->org, &p_org); 1322 NTOHL_FP(&rpkt->rec, &p_rec); 1323 NTOHL_FP(&rpkt->xmt, &p_xmt); 1324 1325 *precision = LOGTOD(rpkt->precision); 1326 1327 TRACE(3, ("offset_calculation: LOGTOD(rpkt->precision): %f\n", *precision)); 1328 1329 /* Compute offset etc. */ 1330 tmp = p_rec; 1331 L_SUB(&tmp, &p_org); 1332 LFPTOD(&tmp, t21); 1333 TVTOTS(tv_dst, &dst); 1334 dst.l_ui += JAN_1970; 1335 tmp = p_xmt; 1336 L_SUB(&tmp, &dst); 1337 LFPTOD(&tmp, t34); 1338 *offset = (t21 + t34) / 2.; 1339 delta = t21 - t34; 1340 1341 // synch_distance is: 1342 // (peer->delay + peer->rootdelay) / 2 + peer->disp 1343 // + peer->rootdisp + clock_phi * (current_time - peer->update) 1344 // + peer->jitter; 1345 // 1346 // and peer->delay = fabs(peer->offset - p_offset) * 2; 1347 // and peer->offset needs history, so we're left with 1348 // p_offset = (t21 + t34) / 2.; 1349 // peer->disp = 0; (we have no history to augment this) 1350 // clock_phi = 15e-6; 1351 // peer->jitter = LOGTOD(sys_precision); (we have no history to augment this) 1352 // and ntp_proto.c:set_sys_tick_precision() should get us sys_precision. 1353 // 1354 // so our answer seems to be: 1355 // 1356 // (fabs(t21 + t34) + peer->rootdelay) / 3. 1357 // + 0 (peer->disp) 1358 // + peer->rootdisp 1359 // + 15e-6 (clock_phi) 1360 // + LOGTOD(sys_precision) 1361 1362 INSIST( FPTOD(p_rdly) >= 0. ); 1363 #if 1 1364 *synch_distance = (fabs(t21 + t34) + FPTOD(p_rdly)) / 3. 1365 + 0. 1366 + FPTOD(p_rdsp) 1367 + 15e-6 1368 + 0. /* LOGTOD(sys_precision) when we can get it */ 1369 ; 1370 INSIST( *synch_distance >= 0. ); 1371 #else 1372 *synch_distance = (FPTOD(p_rdly) + FPTOD(p_rdsp))/2.0; 1373 #endif 1374 1375 #ifdef DEBUG 1376 if (debug > 3) { 1377 printf("sntp rootdelay: %f\n", FPTOD(p_rdly)); 1378 printf("sntp rootdisp: %f\n", FPTOD(p_rdsp)); 1379 printf("sntp syncdist: %f\n", *synch_distance); 1380 1381 pkt_output(rpkt, rpktl, stdout); 1382 1383 printf("sntp offset_calculation: rpkt->reftime:\n"); 1384 l_fp_output(&p_ref, stdout); 1385 printf("sntp offset_calculation: rpkt->org:\n"); 1386 l_fp_output(&p_org, stdout); 1387 printf("sntp offset_calculation: rpkt->rec:\n"); 1388 l_fp_output(&p_rec, stdout); 1389 printf("sntp offset_calculation: rpkt->xmt:\n"); 1390 l_fp_output(&p_xmt, stdout); 1391 } 1392 #endif 1393 1394 TRACE(3, ("sntp offset_calculation:\trec - org t21: %.6f\n" 1395 "\txmt - dst t34: %.6f\tdelta: %.6f\toffset: %.6f\n", 1396 t21, t34, delta, *offset)); 1397 1398 return; 1399 } 1400 1401 1402 1403 /* Compute the 8 bits for li_vn_mode */ 1404 void 1405 set_li_vn_mode ( 1406 struct pkt *spkt, 1407 char leap, 1408 char version, 1409 char mode 1410 ) 1411 { 1412 if (leap > 3) { 1413 msyslog(LOG_DEBUG, "set_li_vn_mode: leap > 3, using max. 3"); 1414 leap = 3; 1415 } 1416 1417 if ((unsigned char)version > 7) { 1418 msyslog(LOG_DEBUG, "set_li_vn_mode: version < 0 or > 7, using 4"); 1419 version = 4; 1420 } 1421 1422 if (mode > 7) { 1423 msyslog(LOG_DEBUG, "set_li_vn_mode: mode > 7, using client mode 3"); 1424 mode = 3; 1425 } 1426 1427 spkt->li_vn_mode = leap << 6; 1428 spkt->li_vn_mode |= version << 3; 1429 spkt->li_vn_mode |= mode; 1430 } 1431 1432 1433 /* 1434 ** set_time applies 'offset' to the local clock. 1435 */ 1436 int 1437 set_time( 1438 double offset 1439 ) 1440 { 1441 int rc; 1442 1443 if (time_adjusted) 1444 return EX_OK; 1445 1446 /* 1447 ** If we can step but we cannot slew, then step. 1448 ** If we can step or slew and and |offset| > steplimit, then step. 1449 */ 1450 if (ENABLED_OPT(STEP) && 1451 ( !ENABLED_OPT(SLEW) 1452 || (ENABLED_OPT(SLEW) && (fabs(offset) > steplimit)) 1453 )) { 1454 rc = step_systime(offset); 1455 1456 /* If there was a problem, can we rely on errno? */ 1457 if (1 == rc) 1458 time_adjusted = TRUE; 1459 return (time_adjusted) 1460 ? EX_OK 1461 : 1; 1462 /* 1463 ** In case of error, what should we use? 1464 ** EX_UNAVAILABLE? 1465 ** EX_OSERR? 1466 ** EX_NOPERM? 1467 */ 1468 } 1469 1470 if (ENABLED_OPT(SLEW)) { 1471 rc = adj_systime(offset); 1472 1473 /* If there was a problem, can we rely on errno? */ 1474 if (1 == rc) 1475 time_adjusted = TRUE; 1476 return (time_adjusted) 1477 ? EX_OK 1478 : 1; 1479 /* 1480 ** In case of error, what should we use? 1481 ** EX_UNAVAILABLE? 1482 ** EX_OSERR? 1483 ** EX_NOPERM? 1484 */ 1485 } 1486 1487 return EX_SOFTWARE; 1488 } 1489 1490 1491 int 1492 libevent_version_ok(void) 1493 { 1494 ev_uint32_t v_compile_maj; 1495 ev_uint32_t v_run_maj; 1496 1497 v_compile_maj = LIBEVENT_VERSION_NUMBER & 0xffff0000; 1498 v_run_maj = event_get_version_number() & 0xffff0000; 1499 if (v_compile_maj != v_run_maj) { 1500 fprintf(stderr, 1501 "Incompatible libevent versions: have %s, built with %s\n", 1502 event_get_version(), 1503 LIBEVENT_VERSION); 1504 return 0; 1505 } 1506 return 1; 1507 } 1508 1509 /* 1510 * gettimeofday_cached() 1511 * 1512 * Clones the event_base_gettimeofday_cached() interface but ensures the 1513 * times are always on the gettimeofday() 1970 scale. Older libevent 2 1514 * sometimes used gettimeofday(), sometimes the since-system-start 1515 * clock_gettime(CLOCK_MONOTONIC), depending on the platform. 1516 * 1517 * It is not cleanly possible to tell which timescale older libevent is 1518 * using. 1519 * 1520 * The strategy involves 1 hour thresholds chosen to be far longer than 1521 * the duration of a round of libevent callbacks, which share a cached 1522 * start-of-round time. First compare the last cached time with the 1523 * current gettimeofday() time. If they are within one hour, libevent 1524 * is using the proper timescale so leave the offset 0. Otherwise, 1525 * compare libevent's cached time and the current time on the monotonic 1526 * scale. If they are within an hour, libevent is using the monotonic 1527 * scale so calculate the offset to add to such times to bring them to 1528 * gettimeofday()'s scale. 1529 */ 1530 int 1531 gettimeofday_cached( 1532 struct event_base * b, 1533 struct timeval * caller_tv 1534 ) 1535 { 1536 #if defined(_EVENT_HAVE_CLOCK_GETTIME) && defined(CLOCK_MONOTONIC) 1537 static struct event_base * cached_b; 1538 static struct timeval cached; 1539 static struct timeval adj_cached; 1540 static struct timeval offset; 1541 static int offset_ready; 1542 struct timeval latest; 1543 struct timeval systemt; 1544 struct timespec ts; 1545 struct timeval mono; 1546 struct timeval diff; 1547 int cgt_rc; 1548 int gtod_rc; 1549 1550 event_base_gettimeofday_cached(b, &latest); 1551 if (b == cached_b && 1552 !memcmp(&latest, &cached, sizeof(latest))) { 1553 *caller_tv = adj_cached; 1554 return 0; 1555 } 1556 cached = latest; 1557 cached_b = b; 1558 if (!offset_ready) { 1559 cgt_rc = clock_gettime(CLOCK_MONOTONIC, &ts); 1560 gtod_rc = gettimeofday(&systemt, NULL); 1561 if (0 != gtod_rc) { 1562 msyslog(LOG_ERR, 1563 "%s: gettimeofday() error %m", 1564 progname); 1565 exit(1); 1566 } 1567 diff = sub_tval(systemt, latest); 1568 if (debug > 1) 1569 printf("system minus cached %+ld.%06ld\n", 1570 (long)diff.tv_sec, (long)diff.tv_usec); 1571 if (0 != cgt_rc || labs((long)diff.tv_sec) < 3600) { 1572 /* 1573 * Either use_monotonic == 0, or this libevent 1574 * has been repaired. Leave offset at zero. 1575 */ 1576 } else { 1577 mono.tv_sec = ts.tv_sec; 1578 mono.tv_usec = ts.tv_nsec / 1000; 1579 diff = sub_tval(latest, mono); 1580 if (debug > 1) 1581 printf("cached minus monotonic %+ld.%06ld\n", 1582 (long)diff.tv_sec, (long)diff.tv_usec); 1583 if (labs((long)diff.tv_sec) < 3600) { 1584 /* older libevent2 using monotonic */ 1585 offset = sub_tval(systemt, mono); 1586 TRACE(1, ("%s: Offsetting libevent CLOCK_MONOTONIC times by %+ld.%06ld\n", 1587 "gettimeofday_cached", 1588 (long)offset.tv_sec, 1589 (long)offset.tv_usec)); 1590 } 1591 } 1592 offset_ready = TRUE; 1593 } 1594 adj_cached = add_tval(cached, offset); 1595 *caller_tv = adj_cached; 1596 1597 return 0; 1598 #else 1599 return event_base_gettimeofday_cached(b, caller_tv); 1600 #endif 1601 } 1602 1603