diff options
| -rw-r--r-- | include/usage.h | 3 | ||||
| -rw-r--r-- | networking/ntpd.c | 330 |
2 files changed, 157 insertions, 176 deletions
diff --git a/include/usage.h b/include/usage.h index 760e8545b..6978bb6e9 100644 --- a/include/usage.h +++ b/include/usage.h @@ -3217,9 +3217,8 @@ "\nOptions:" \ "\n -d Verbose" \ "\n -n Do not daemonize" \ - "\n -g Set system time even if offset is > 1000 sec" \ "\n -q Quit after clock is set" \ -/* -N exists for mostly compat reasons, thus Not essential to inform */ \ +/* -N exists for mostly compat reasons, thus not essential to inform */ \ /* the user that it exists: user may use nice as well */ \ /* "\n -N Run at high priority" */ \ "\n -l Run as server on port 123" \ diff --git a/networking/ntpd.c b/networking/ntpd.c index 320477c13..3bca69a4c 100644 --- a/networking/ntpd.c +++ b/networking/ntpd.c @@ -14,11 +14,14 @@ # error "Sorry, your kernel has to support IP_PKTINFO" #endif -#define INTERVAL_QUERY_NORMAL 30 /* sync to peers every n secs */ + +/* Sync to peers every N secs */ +#define INTERVAL_QUERY_NORMAL 30 #define INTERVAL_QUERY_PATHETIC 60 #define INTERVAL_QUERY_AGRESSIVE 5 -#define TRUSTLEVEL_BADPEER 6 /* bad if *less than* TRUSTLEVEL_BADPEER */ +/* Bad if *less than* TRUSTLEVEL_BADPEER */ +#define TRUSTLEVEL_BADPEER 6 #define TRUSTLEVEL_PATHETIC 2 #define TRUSTLEVEL_AGRESSIVE 8 #define TRUSTLEVEL_MAX 10 @@ -26,30 +29,11 @@ #define QSCALE_OFF_MIN 0.05 #define QSCALE_OFF_MAX 0.50 -#define QUERYTIME_MAX 15 /* single query might take n secs max */ -#define OFFSET_ARRAY_SIZE 8 -#define SETTIME_MIN_OFFSET 180 /* min offset for settime at start */ -#define SETTIME_TIMEOUT 15 /* max seconds to wait with -s */ - -/* Style borrowed from NTP ref/tcpdump and updated for SNTPv4 (RFC2030). */ +/* Single query might take n secs max */ +#define QUERYTIME_MAX 15 +/* Min offset for settime at start. "man ntpd" says it's 128 ms */ +#define STEPTIME_MIN_OFFSET 0.128 -/* - * RFC Section 3 - * - * 0 1 2 3 - * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 - * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - * | Integer Part | - * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - * | Fraction Part | - * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - * - * 0 1 2 3 - * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 - * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - * | Integer Part | Fraction Part | - * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -*/ typedef struct { uint32_t int_partl; uint32_t fractionl; @@ -85,7 +69,7 @@ typedef struct { enum { NTP_VERSION = 4, NTP_MAXSTRATUM = 15, - /* Leap Second Codes (high order two bits) */ + /* Leap Second Codes (high order two bits of m_status) */ LI_NOWARNING = (0 << 6), /* no warning */ LI_PLUSSEC = (1 << 6), /* add a second (61 seconds) */ LI_MINUSSEC = (2 << 6), /* minus a second (59 seconds) */ @@ -121,33 +105,28 @@ typedef struct { uint8_t o_good; } ntp_offset_t; +#define OFFSET_ARRAY_SIZE 8 typedef struct { -//TODO: periodically re-resolve DNS names? len_and_sockaddr *lsa; + char *hostname; char *dotted; - double xmttime; - time_t next; - time_t deadline; + /* When to send new query (if fd == -1) + * or when receive times out (if fd >= 0): */ + time_t next_action_time; int fd; - uint8_t state; uint8_t shift; uint8_t trustlevel; ntp_msg_t msg; + double xmttime; ntp_offset_t update; ntp_offset_t reply[OFFSET_ARRAY_SIZE]; } ntp_peer_t; -/* for ntp_peer_t::state */ -enum { - STATE_NONE, - STATE_QUERY_SENT, - STATE_REPLY_RECEIVED, -}; enum { OPT_n = (1 << 0), - OPT_g = (1 << 1), - OPT_q = (1 << 2), - OPT_N = (1 << 3), + OPT_q = (1 << 1), + OPT_N = (1 << 2), + OPT_x = (1 << 3), /* Insert new options above this line. */ /* Non-compat options: */ OPT_p = (1 << 4), @@ -164,12 +143,13 @@ struct globals { #endif unsigned verbose; unsigned peer_cnt; + unsigned scale; uint32_t refid; uint32_t refid4; - uint32_t scale; uint8_t synced; uint8_t leap; - int8_t precision; +#define G_precision -6 +// int8_t precision; uint8_t stratum; uint8_t time_is_stepped; uint8_t first_adj_done; @@ -183,32 +163,28 @@ static const int const_IPTOS_LOWDELAY = IPTOS_LOWDELAY; static void set_next(ntp_peer_t *p, unsigned t) { - p->next = time(NULL) + t; - p->deadline = 0; + p->next_action_time = time(NULL) + t; } static void -add_peers(const char *s) +add_peers(char *s) { ntp_peer_t *p; p = xzalloc(sizeof(*p)); -//TODO: big ntpd uses all IPs, not just 1st, do we need to mimic that? - p->lsa = xhost2sockaddr(s, 123); - p->dotted = xmalloc_sockaddr2dotted_noport(&p->lsa->u.sa); + p->hostname = s; + p->dotted = s; p->fd = -1; p->msg.m_status = MODE_CLIENT | (NTP_VERSION << 3); - if (STATE_NONE != 0) - p->state = STATE_NONE; p->trustlevel = TRUSTLEVEL_PATHETIC; - set_next(p, 0); + p->next_action_time = time(NULL); /* = set_next(p, 0); */ llist_add_to(&G.ntp_peers, p); G.peer_cnt++; } static double -gettime1900fp(void) +gettime1900d(void) { struct timeval tv; gettimeofday(&tv, NULL); /* never fails */ @@ -268,13 +244,6 @@ d_to_sfp(double d) } #endif -static void -set_deadline(ntp_peer_t *p, time_t t) -{ - p->deadline = time(NULL) + t; - p->next = 0; -} - static unsigned error_interval(void) { @@ -328,8 +297,18 @@ send_query_to_peer(ntp_peer_t *p) int fd, family; len_and_sockaddr *local_lsa; +//TODO: big ntpd uses all IPs, not just 1st, do we need to mimic that? +//TODO: periodically re-resolve DNS names? + if (!p->lsa) { + p->lsa = host2sockaddr(p->hostname, 123); + if (!p->lsa) { + set_next(p, INTERVAL_QUERY_PATHETIC); + return -1; + } + p->dotted = xmalloc_sockaddr2dotted_noport(&p->lsa->u.sa); + } + family = p->lsa->u.sa.sa_family; - //was: p->fd = xsocket(family, SOCK_DGRAM, 0); p->fd = fd = xsocket_type(&local_lsa, family, SOCK_DGRAM); /* local_lsa has "null" address and port 0 now. * bind() ensures we have a *particular port* selected by kernel @@ -362,23 +341,70 @@ send_query_to_peer(ntp_peer_t *p) p->msg.m_xmttime.int_partl = random(); p->msg.m_xmttime.fractionl = random(); - p->xmttime = gettime1900fp(); + p->xmttime = gettime1900d(); if (do_sendto(p->fd, /*from:*/ NULL, /*to:*/ &p->lsa->u.sa, /*addrlen:*/ p->lsa->len, &p->msg, NTP_MSGSIZE_NOAUTH) == -1 ) { + close(p->fd); + p->fd = -1; set_next(p, INTERVAL_QUERY_PATHETIC); return -1; } if (G.verbose) bb_error_msg("sent query to %s", p->dotted); - p->state = STATE_QUERY_SENT; - set_deadline(p, QUERYTIME_MAX); + set_next(p, QUERYTIME_MAX); return 0; } + +/* Time is stepped only once, when the first packet from a peer is received. + */ +static void +step_time_once(double offset) +{ + llist_t *item; + struct timeval tv; + char buf[80]; + time_t tval; + + if (G.time_is_stepped) + goto bail; + G.time_is_stepped = 1; + + /* if the offset is small, don't step, slew (later) */ + if (offset < STEPTIME_MIN_OFFSET && offset > -STEPTIME_MIN_OFFSET) + goto bail; + + gettimeofday(&tv, NULL); /* never fails */ + offset += tv.tv_sec; + offset += 1.0e-6 * tv.tv_usec; + d_to_tv(offset, &tv); + + if (settimeofday(&tv, NULL) == -1) + bb_perror_msg_and_die("settimeofday"); + + tval = tv.tv_sec; + strftime(buf, sizeof(buf), "%a %b %e %H:%M:%S %Z %Y", localtime(&tval)); + + bb_error_msg("setting clock to %s (offset %fs)", buf, offset); + + for (item = G.ntp_peers; item != NULL; item = item->link) { + ntp_peer_t *p = (ntp_peer_t *) item->data; + p->next_action_time -= offset; + } + + bail: + if (option_mask32 & OPT_q) + exit(0); +} + + +/* Time is periodically slewed when we collect enough + * good data points. + */ static int compare_offsets(const void *aa, const void *bb) { @@ -388,8 +414,7 @@ compare_offsets(const void *aa, const void *bb) return -1; return ((*a)->update.o_offset > (*b)->update.o_offset); } - -static uint32_t +static unsigned updated_scale(double offset) { if (offset < 0) @@ -400,7 +425,6 @@ updated_scale(double offset) return QSCALE_OFF_MAX / QSCALE_OFF_MIN; return QSCALE_OFF_MAX / offset; } - static void slew_time(void) { @@ -409,7 +433,6 @@ slew_time(void) struct timeval tv; { - len_and_sockaddr *lsa; ntp_peer_t **peers = xzalloc(sizeof(peers[0]) * G.peer_cnt); unsigned goodpeer_cnt = 0; unsigned middle; @@ -418,8 +441,10 @@ slew_time(void) ntp_peer_t *p = (ntp_peer_t *) item->data; if (p->trustlevel < TRUSTLEVEL_BADPEER) continue; - if (!p->update.o_good) + if (!p->update.o_good) { + free(peers); return; + } peers[goodpeer_cnt++] = p; } @@ -442,38 +467,38 @@ slew_time(void) } G.leap = peers[middle]->update.o_leap; G.refid4 = peers[middle]->update.o_refid4; - lsa = peers[middle]->lsa; G.refid = #if ENABLE_FEATURE_IPV6 - lsa->u.sa.sa_family != AF_INET ? + peers[middle]->lsa->u.sa.sa_family != AF_INET ? G.refid4 : #endif - lsa->u.sin.sin_addr.s_addr; + peers[middle]->lsa->u.sin.sin_addr.s_addr; free(peers); } +//TODO: if (offset_median > BIG) step_time(offset_median)? - bb_error_msg("adjusting clock by %fs, our stratum is %u", offset_median, G.stratum); + G.scale = updated_scale(offset_median); + + bb_error_msg("adjusting clock by %fs, our stratum is %u, time scale %u", + offset_median, G.stratum, G.scale); errno = 0; d_to_tv(offset_median, &tv); - if (adjtime(&tv, &tv) == -1) { - bb_perror_msg("adjtime failed"); //TODO: maybe _and_die? - } else { - if (G.verbose >= 2) - bb_error_msg("old adjust: %d.%06u", (int)tv.tv_sec, (unsigned)tv.tv_usec); - if (G.first_adj_done) { - uint8_t synced = (tv.tv_sec == 0 && tv.tv_usec == 0); - if (synced != G.synced) { - G.synced = synced; - bb_error_msg("clock is %ssynced", synced ? "" : "un"); - } + if (adjtime(&tv, &tv) == -1) + bb_perror_msg_and_die("adjtime failed"); + if (G.verbose >= 2) + bb_error_msg("old adjust: %d.%06u", (int)tv.tv_sec, (unsigned)tv.tv_usec); + + if (G.first_adj_done) { + uint8_t synced = (tv.tv_sec == 0 && tv.tv_usec == 0); + if (synced != G.synced) { + G.synced = synced; + bb_error_msg("clock is %ssynced", synced ? "" : "un"); } - G.first_adj_done = 1; } + G.first_adj_done = 1; - G.reftime = gettime1900fp(); -//TODO: log if G.scale changed? - G.scale = updated_scale(offset_median); + G.reftime = gettime1900d(); clear_good: for (item = G.ntp_peers; item != NULL; item = item->link) { @@ -483,52 +508,6 @@ slew_time(void) } static void -step_time_once(double offset) -{ - ntp_peer_t *p; - llist_t *item; - struct timeval tv; - char buf[80]; - time_t tval; - - if (G.time_is_stepped) - goto bail; - G.time_is_stepped = 1; - - /* if the offset is small, don't call settimeofday */ - if (offset < SETTIME_MIN_OFFSET && offset > -SETTIME_MIN_OFFSET) - goto bail; - - gettimeofday(&tv, NULL); /* never fails */ - offset += tv.tv_sec; - offset += 1.0e-6 * tv.tv_usec; - d_to_tv(offset, &tv); - - if (settimeofday(&tv, NULL) == -1) { - bb_perror_msg("settimeofday"); - goto bail; - } - - tval = tv.tv_sec; - strftime(buf, sizeof(buf), "%a %b %e %H:%M:%S %Z %Y", localtime(&tval)); - -// Do we want to print message below to system log when daemonized? - bb_error_msg("setting clock to %s (offset %fs)", buf, offset); - - for (item = G.ntp_peers; item != NULL; item = item->link) { - p = (ntp_peer_t *) item->data; - if (p->next) - p->next -= offset; - if (p->deadline) - p->deadline -= offset; - } - - bail: - if (option_mask32 & OPT_q) - exit(0); -} - -static void update_peer_data(ntp_peer_t *p) { /* Clock filter. @@ -567,7 +546,6 @@ scale_interval(unsigned requested) r = (unsigned)random() % (unsigned)(MAX(5, interval / 10)); return (interval + r); } - static void recv_and_process_peer_pkt(ntp_peer_t *p) { @@ -631,7 +609,7 @@ recv_and_process_peer_pkt(ntp_peer_t *p) * d = (T4 - T1) - (T3 - T2) t = ((T2 - T1) + (T3 - T4)) / 2. */ - T4 = gettime1900fp(); + T4 = gettime1900d(); T1 = p->xmttime; T2 = lfp_to_d(msg.m_rectime); T3 = lfp_to_d(msg.m_xmttime); @@ -668,7 +646,6 @@ recv_and_process_peer_pkt(ntp_peer_t *p) interval = scale_interval(INTERVAL_QUERY_NORMAL); set_next(p, interval); - p->state = STATE_REPLY_RECEIVED; /* every received reply which we do not discard increases trust */ if (p->trustlevel < TRUSTLEVEL_MAX) { @@ -690,7 +667,7 @@ recv_and_process_peer_pkt(ntp_peer_t *p) p->shift = 0; close_sock: - /* We do not expect any more packets for now. + /* We do not expect any more packets from this peer for now. * Closing the socket informs kernel about it. * We open a new socket when we send a new query. */ @@ -723,10 +700,10 @@ recv_and_process_client_pkt(void /*int fd*/) if (size < 0) { if (errno == EAGAIN) goto bail; - bb_perror_msg_and_die("recv_from_to"); + bb_perror_msg_and_die("recv"); } addr = xmalloc_sockaddr2dotted_noport(from); - bb_error_msg("malformed packet received from %s", addr); + bb_error_msg("malformed packet received from %s: size %u", addr, (int)size); free(addr); goto bail; } @@ -743,11 +720,11 @@ recv_and_process_client_pkt(void /*int fd*/) MODE_SERVER : MODE_SYM_PAS; msg.m_stratum = G.stratum; msg.m_ppoll = query_ppoll; - msg.m_precision = G.precision; - rectime = gettime1900fp(); + msg.m_precision = G_precision; + rectime = gettime1900d(); msg.m_xmttime = msg.m_rectime = d_to_lfp(rectime); msg.m_reftime = d_to_lfp(G.reftime); - //msg.m_xmttime = d_to_lfp(gettime1900fp()); // = msg.m_rectime + //msg.m_xmttime = d_to_lfp(gettime1900d()); // = msg.m_rectime msg.m_orgtime = query_xmttime; msg.m_rootdelay = d_to_sfp(G.rootdelay); version = (query_status & VERSION_MASK); /* ... >> VERSION_SHIFT - done below instead */ @@ -859,7 +836,6 @@ static NOINLINE void ntp_init(char **argv) llist_t *peers; srandom(getpid()); - /* tzset(); - why? it's called automatically when needed, no? */ if (getuid()) bb_error_msg_and_die(bb_msg_you_must_be_root); @@ -867,16 +843,15 @@ static NOINLINE void ntp_init(char **argv) peers = NULL; opt_complementary = "dd:p::"; /* d: counter, p: list */ opts = getopt32(argv, - "ngqN" /* compat */ + "nqNx" /* compat */ "p:"IF_FEATURE_NTPD_SERVER("l") /* NOT compat */ "d" /* compat */ - "46aAbLx", /* compat, ignored */ + "46aAbgL", /* compat, ignored */ &peers, &G.verbose); if (!(opts & (OPT_p|OPT_l))) bb_show_usage(); -//WRONG -// if (opts & OPT_g) -// G.time_is_stepped = 1; + if (opts & OPT_x) /* disable stepping, only slew is allowed */ + G.time_is_stepped = 1; while (peers) add_peers(llist_pop(&peers)); if (!(opts & OPT_n)) { @@ -896,23 +871,28 @@ static NOINLINE void ntp_init(char **argv) setpriority(PRIO_PROCESS, 0, -15); /* Set some globals */ +#if 0 + /* With constant b = 100, G.precision is also constant -6. + * Uncomment this and you'll see */ { int prec = 0; int b; -#if 0 +# if 0 struct timespec tp; /* We can use sys_clock_getres but assuming 10ms tick should be fine */ clock_getres(CLOCK_REALTIME, &tp); tp.tv_sec = 0; tp.tv_nsec = 10000000; b = 1000000000 / tp.tv_nsec; /* convert to Hz */ -#else +# else b = 100; /* b = 1000000000/10000000 = 100 */ -#endif +# endif while (b > 1) prec--, b >>= 1; - G.precision = prec; + //G.precision = prec; + bb_error_msg("G.precision:%d", prec); /* -6 */ } +#endif G.scale = 1; bb_signals((1 << SIGTERM) | (1 << SIGINT), record_signo); @@ -963,31 +943,33 @@ int ntpd_main(int argc UNUSED_PARAM, char **argv) for (item = g.ntp_peers; item != NULL; item = item->link) { ntp_peer_t *p = (ntp_peer_t *) item->data; - if (p->next != 0 && p->next <= cur_time) { - /* Time to send new req */ - trial_cnt++; - if (send_query_to_peer(p) == 0) - sent_cnt++; - } - if (p->deadline != 0 && p->deadline <= cur_time) { - /* Timed out waiting for reply */ - timeout = error_interval(); - bb_error_msg("timed out waiting for %s, " - "next query in %us", p->dotted, timeout); - if (p->trustlevel >= TRUSTLEVEL_BADPEER) { - p->trustlevel /= 2; - if (p->trustlevel < TRUSTLEVEL_BADPEER) - bb_error_msg("peer %s now invalid", p->dotted); + /* Overflow-safe "if (p->next_action_time <= cur_time) ..." */ + if ((int)(cur_time - p->next_action_time) >= 0) { + if (p->fd == -1) { + /* Time to send new req */ + trial_cnt++; + if (send_query_to_peer(p) == 0) + sent_cnt++; + } else { + /* Timed out waiting for reply */ + close(p->fd); + p->fd = -1; + timeout = error_interval(); + bb_error_msg("timed out waiting for %s, " + "next query in %us", p->dotted, timeout); + if (p->trustlevel >= TRUSTLEVEL_BADPEER) { + p->trustlevel /= 2; + if (p->trustlevel < TRUSTLEVEL_BADPEER) + bb_error_msg("peer %s now invalid", p->dotted); + } + set_next(p, timeout); } - set_next(p, timeout); } - if (p->next != 0 && p->next < nextaction) - nextaction = p->next; - if (p->deadline != 0 && p->deadline < nextaction) - nextaction = p->deadline; + if (p->next_action_time < nextaction) + nextaction = p->next_action_time; - if (p->state == STATE_QUERY_SENT) { + if (p->fd >= 0) { /* Wait for reply from this peer */ pfd[i].fd = p->fd; pfd[i].events = POLLIN; @@ -1005,7 +987,7 @@ int ntpd_main(int argc UNUSED_PARAM, char **argv) /* Here we may block */ if (g.verbose >= 2) - bb_error_msg("poll %u sec, sockets:%u", timeout, i); + bb_error_msg("poll %us, sockets:%u", timeout, i); nfds = poll(pfd, i, timeout * 1000); if (nfds <= 0) continue; |