NetBSD/dist/ntp/ntpd/ntp_resolver.c

992 lines
22 KiB
C

/* $NetBSD: ntp_resolver.c,v 1.1.1.1 2000/04/22 14:53:21 simonb Exp $ */
/*
** Ancestor was ripped off from ../ntpres/ntpres.c by Greg Troxel 4/2/92
**
** The previous resolver only needed to do forward lookups, and all names
** were known before we started the resolver process.
**
** The new code must be able to handle reverse lookups, and the requests can
** show up at any time.
**
** Here's the drill for the new logic.
**
** We want to be able to do forward or reverse lookups. Forward lookups
** require one set of information to be sent back to the daemon, reverse
** lookups require a different set of information. The caller knows this.
**
** The daemon must not block. This includes communicating with the resolver
** process (if the resolver process is a separate task).
**
** Current resolver code blocks waiting for the response, so the
** alternatives are:
**
** - Find a nonblocking resolver library
** - Do each (initial) lookup in a separate process
** - - subsequent lookups *could* be handled by a different process that has
** a queue of pending requests
**
** We could use nonblocking lookups in a separate process (just to help out
** with timers).
**
** If we don't have nonblocking resolver calls we have more opportunities
** for denial-of-service problems.
**
** - too many fork()s
** - communications path
**
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <stdio.h>
#include <ctype.h>
#include <sys/types.h>
#include <sys/time.h>
#include <netdb.h>
#include <signal.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include "ntpd.h"
#include "ntp_io.h"
#include "ntp_request.h"
#include "ntp_stdlib.h"
#include "ntp_syslog.h"
#define STREQ(a, b) (*(a) == *(b) && strcmp((a), (b)) == 0)
/*
* Each item we are to resolve and configure gets one of these
* structures defined for it.
*/
struct dns_entry {
int de_done;
#define DE_NAME 001
#define DE_ADDR 002
#define DE_NA (DE_NAME | DE_ADDR)
#define DE_PENDING 000
#define DE_GOT 010
#define DE_FAIL 020
#define DE_RESULT (DE_PENDING | DE_GOT | DE_FAIL)
struct dns_entry *de_next;
struct info_dns_assoc de_info; /* DNS info for peer */
};
#define de_associd de_info.associd
#define de_peeraddr de_info.peeraddr
#define de_hostname de_info.hostname
/*
* dns_entries is a pointer to the list of configuration entries
* we have left to do.
*/
static struct dns_entry *dns_entries = NULL;
/*
* We take an interrupt every thirty seconds, at which time we decrement
* config_timer and resolve_timer. The former is set to 2, so we retry
* unsucessful reconfigurations every minute. The latter is set to
* an exponentially increasing value which starts at 2 and increases to
* 32. When this expires we retry failed name resolutions.
*
* We sleep SLEEPTIME seconds before doing anything, to give the server
* time to arrange itself.
*/
#define MINRESOLVE 2
#define MAXRESOLVE 32
#define CONFIG_TIME 2
#define ALARM_TIME 30
#define SLEEPTIME 2
static volatile int config_timer = 0;
static volatile int resolve_timer = 0;
static int resolve_value; /* next value of resolve timer */
/*
* Big hack attack
*/
#define LOCALHOST 0x7f000001 /* 127.0.0.1, in hex, of course */
#define SKEWTIME 0x08000000 /* 0.03125 seconds as a l_fp fraction */
/*
* Select time out. Set to 2 seconds. The server is on the local machine,
* after all.
*/
#define TIMEOUT_SEC 2
#define TIMEOUT_USEC 0
/*
* File descriptor for ntp request code.
*/
static int sockfd = -1;
/*
* Pipe descriptors
*/
int p_fd[2] = { -1, -1 };
/* stuff to be filled in by caller */
extern keyid_t req_keyid; /* request keyid */
/* end stuff to be filled in */
void ntp_res P((void));
static RETSIGTYPE bong P((int));
static void checkparent P((void));
static void removeentry P((struct dns_entry *));
static void addentry P((char *, u_int32, u_short));
static void findhostaddr P((struct dns_entry *));
static void openntp P((void));
static int tell_ntpd P((struct info_dns_assoc *));
static void doconfigure P((int));
struct ntp_res_t_pkt { /* Tagged packet: */
void *tag; /* For the caller */
u_int32 paddr; /* IP to look up, or 0 */
char name[NTP_MAXHOSTNAME]; /* Name to look up (if 1st byte is not 0) */
};
struct ntp_res_c_pkt { /* Control packet: */
char name[NTP_MAXHOSTNAME];
u_int32 paddr;
int mode;
int version;
int minpoll;
int maxpoll;
int flags;
int ttl;
keyid_t keyid;
u_char keystr[MAXFILENAME];
};
/*
* ntp_res_name
*/
void
ntp_res_name(
u_int32 paddr, /* Address to resolve */
u_short associd /* Association ID */
)
{
pid_t pid;
/*
* fork.
* - parent returns
* - child stuffs data and calls ntp_res()
*/
for (pid = -1; pid == -1;) {
#ifdef RES_TEST
pid = 0;
#else
pid = fork();
#endif
if (pid == -1) {
msyslog(LOG_ERR, "ntp_res_name: fork() failed: %m");
sleep(2);
}
}
switch (pid) {
case -1: /* Error */
msyslog(LOG_INFO, "ntp_res_name: error...");
/* Can't happen */
break;
case 0: /* Child */
closelog();
kill_asyncio();
(void) signal_no_reset(SIGCHLD, SIG_DFL);
#ifndef LOG_DAEMON
openlog("ntp_res", LOG_PID);
# else /* LOG_DAEMON */
# ifndef LOG_NTP
# define LOG_NTP LOG_DAEMON
# endif
openlog("ntp_res_name", LOG_PID | LOG_NDELAY, LOG_NTP);
#endif
addentry(NULL, paddr, associd);
ntp_res();
break;
default: /* Parent */
/* Nothing to do. (In Real Life, this never happens.) */
return;
}
}
/*
* ntp_res needs;
*
* req_key(???), req_keyid valid
* syslog still open
*/
void
ntp_res(void)
{
#ifdef HAVE_SIGSUSPEND
sigset_t set;
sigemptyset(&set);
#endif /* HAVE_SIGSUSPEND */
#ifdef DEBUG
if (debug) {
msyslog(LOG_INFO, "NTP_RESOLVER running");
}
#endif
/* check out auth stuff */
if (sys_authenticate) {
if (!authistrusted(req_keyid)) {
msyslog(LOG_ERR, "invalid request keyid %08x",
req_keyid );
exit(1);
}
}
/*
* Make a first cut at resolving the bunch
*/
doconfigure(1);
if (dns_entries == NULL) {
if (debug) {
msyslog(LOG_INFO, "NTP_RESOLVER done!");
}
#if defined SYS_WINNT
ExitThread(0); /* Don't want to kill whole NT process */
#else
exit(0); /* done that quick */
#endif
}
/*
* Here we've got some problem children. Set up the timer
* and wait for it.
*/
resolve_value = resolve_timer = MINRESOLVE;
config_timer = CONFIG_TIME;
#ifndef SYS_WINNT
(void) signal_no_reset(SIGALRM, bong);
alarm(ALARM_TIME);
#endif /* SYS_WINNT */
for (;;) {
if (dns_entries == NULL)
exit(0);
checkparent();
if (resolve_timer == 0) {
if (resolve_value < MAXRESOLVE)
resolve_value <<= 1;
resolve_timer = resolve_value;
#ifdef DEBUG
msyslog(LOG_INFO, "resolve_timer: 0->%d", resolve_timer);
#endif
config_timer = CONFIG_TIME;
doconfigure(1);
continue;
} else if (config_timer == 0) {
config_timer = CONFIG_TIME;
#ifdef DEBUG
msyslog(LOG_INFO, "config_timer: 0->%d", config_timer);
#endif
doconfigure(0);
continue;
}
#ifndef SYS_WINNT
/*
* There is a race in here. Is okay, though, since
* all it does is delay things by 30 seconds.
*/
# ifdef HAVE_SIGSUSPEND
sigsuspend(&set);
# else
sigpause(0);
# endif /* HAVE_SIGSUSPEND */
#else
if (config_timer > 0)
config_timer--;
if (resolve_timer > 0)
resolve_timer--;
sleep(ALARM_TIME);
#endif /* SYS_WINNT */
}
}
#ifndef SYS_WINNT
/*
* bong - service and reschedule an alarm() interrupt
*/
static RETSIGTYPE
bong(
int sig
)
{
if (config_timer > 0)
config_timer--;
if (resolve_timer > 0)
resolve_timer--;
alarm(ALARM_TIME);
}
#endif /* SYS_WINNT */
/*
* checkparent - see if our parent process is still running
*
* No need to worry in the Windows NT environment whether the
* main thread is still running, because if it goes
* down it takes the whole process down with it (in
* which case we won't be running this thread either)
* Turn function into NOP;
*/
static void
checkparent(void)
{
#if !defined (SYS_WINNT) && !defined (SYS_VXWORKS)
/*
* If our parent (the server) has died we will have been
* inherited by init. If so, exit.
*/
if (getppid() == 1) {
msyslog(LOG_INFO, "parent died before we finished, exiting");
exit(0);
}
#endif /* SYS_WINNT && SYS_VXWORKS*/
}
/*
* removeentry - we are done with an entry, remove it from the list
*/
static void
removeentry(
struct dns_entry *entry
)
{
register struct dns_entry *de;
de = dns_entries;
if (de == entry) {
dns_entries = de->de_next;
return;
}
while (de != NULL) {
if (de->de_next == entry) {
de->de_next = entry->de_next;
return;
}
de = de->de_next;
}
}
/*
* addentry - add an entry to the configuration list
*/
static void
addentry(
char *name,
u_int32 paddr,
u_short associd
)
{
register struct dns_entry *de;
#ifdef DEBUG
if (debug > 1) {
struct in_addr si;
si.s_addr = paddr;
msyslog(LOG_INFO,
"ntp_res_name: <%s> %s associd %d\n",
(name) ? name : "", inet_ntoa(si), associd);
}
#endif
de = (struct dns_entry *)emalloc(sizeof(struct dns_entry));
if (name) {
strncpy(de->de_hostname, name, sizeof de->de_hostname);
de->de_done = DE_PENDING | DE_ADDR;
} else {
de->de_hostname[0] = 0;
de->de_done = DE_PENDING | DE_NAME;
}
de->de_peeraddr = paddr;
de->de_associd = associd;
de->de_next = NULL;
if (dns_entries == NULL) {
dns_entries = de;
} else {
register struct dns_entry *dep;
for (dep = dns_entries; dep->de_next != NULL;
dep = dep->de_next)
/* nothing */;
dep->de_next = de;
}
}
/*
* findhostaddr - resolve a host name into an address (Or vice-versa)
*
* sets entry->de_done appropriately when we're finished. We're finished if
* we either successfully look up the missing name or address, or if we get a
* "permanent" failure on the lookup.
*
*/
static void
findhostaddr(
struct dns_entry *entry
)
{
struct hostent *hp;
checkparent(); /* make sure our guy is still running */
/*
* The following should never trip - this subroutine isn't
* called if hostname and peeraddr are "filled".
*/
if (entry->de_hostname[0] && entry->de_peeraddr) {
struct in_addr si;
si.s_addr = entry->de_peeraddr;
msyslog(LOG_ERR, "findhostaddr: both de_hostname and de_peeraddr are defined: <%s>/%s: state %#x",
&entry->de_hostname[0], inet_ntoa(si), entry->de_done);
return;
}
/*
* The following should never trip.
*/
if (!entry->de_hostname[0] && !entry->de_peeraddr) {
msyslog(LOG_ERR, "findhostaddr: both de_hostname and de_peeraddr are undefined!");
entry->de_done |= DE_FAIL;
return;
}
if (entry->de_hostname[0]) {
#ifdef DEBUG
if (debug > 2)
msyslog(LOG_INFO, "findhostaddr: Resolving <%s>",
&entry->de_hostname[0]);
#endif DEBUG
hp = gethostbyname(&entry->de_hostname[0]);
} else {
#ifdef DEBUG
if (debug > 2) {
struct in_addr si;
si.s_addr = entry->de_peeraddr;
msyslog(LOG_INFO, "findhostaddr: Resolving %s",
inet_ntoa(si));
}
#endif
hp = gethostbyaddr((const char *)&entry->de_peeraddr,
sizeof entry->de_peeraddr,
AF_INET);
}
if (hp == NULL) {
/*
* Bail if we should TRY_AGAIN.
* Otherwise, we have a permanent failure.
*/
if (h_errno == TRY_AGAIN)
return;
entry->de_done |= DE_FAIL;
} else {
entry->de_done |= DE_GOT;
}
if (entry->de_done & DE_GOT) {
switch (entry->de_done & DE_NA) {
case DE_NAME:
#ifdef DEBUG
if (debug > 2)
msyslog(LOG_INFO,
"findhostaddr: name resolved.");
#endif
/*
* Use the first address. We don't have any way to
* tell preferences and older gethostbyname()
* implementations only return one.
*/
memmove((char *)&(entry->de_peeraddr),
(char *)hp->h_addr,
sizeof(struct in_addr));
break;
case DE_ADDR:
#ifdef DEBUG
if (debug > 2)
msyslog(LOG_INFO,
"findhostaddr: address resolved.");
#endif
strncpy(&entry->de_hostname[0], hp->h_name,
sizeof entry->de_hostname);
break;
default:
msyslog(LOG_ERR, "findhostaddr: Bogus de_done: %#x",
entry->de_done);
break;
}
} else {
#ifdef DEBUG
if (debug > 2) {
struct in_addr si;
char *hes;
#ifndef HAVE_HSTRERROR
char hnum[20];
switch (h_errno) {
case HOST_NOT_FOUND:
hes = "Authoritive Answer Host not found";
break;
case TRY_AGAIN:
hes = "Non-Authoritative Host not found, or SERVERFAIL";
break;
case NO_RECOVERY:
hes = "Non recoverable errors, FORMERR, REFUSED, NOTIMP";
break;
case NO_DATA:
hes = "Valid name, no data record of requested type";
break;
default:
snprintf(hnum, sizeof hnum, "%d", h_errno);
hes = hnum;
break;
}
#else
hes = hstrerror(h_errno);
#endif
si.s_addr = entry->de_peeraddr;
msyslog(LOG_INFO,
"findhostaddr: Failed resolution on <%s>/%s: %s",
entry->de_hostname, inet_ntoa(si), hes);
}
#endif
/* Send a NAK message back to the daemon */
}
return;
}
/*
* openntp - open a socket to the ntp server
*/
static void
openntp(void)
{
struct sockaddr_in saddr;
if (sockfd >= 0)
return;
sockfd = socket(AF_INET, SOCK_DGRAM, 0);
if (sockfd == -1) {
msyslog(LOG_ERR, "socket() failed: %m");
exit(1);
}
memset((char *)&saddr, 0, sizeof(saddr));
saddr.sin_family = AF_INET;
saddr.sin_port = htons(NTP_PORT); /* trash */
saddr.sin_addr.s_addr = htonl(LOCALHOST); /* garbage */
/*
* Make the socket non-blocking. We'll wait with select()
*/
#ifndef SYS_WINNT
# if defined(O_NONBLOCK)
if (fcntl(sockfd, F_SETFL, O_NONBLOCK) == -1) {
msyslog(LOG_ERR, "fcntl(O_NONBLOCK) failed: %m");
exit(1);
}
# else
# if defined(FNDELAY)
if (fcntl(sockfd, F_SETFL, FNDELAY) == -1) {
msyslog(LOG_ERR, "fcntl(FNDELAY) failed: %m");
exit(1);
}
# else
# include "Bletch: NEED NON BLOCKING IO"
# endif /* FNDDELAY */
# endif /* O_NONBLOCK */
#else /* SYS_WINNT */
{
int on = 1;
if (ioctlsocket(sockfd,FIONBIO,(u_long *) &on) == SOCKET_ERROR) {
msyslog(LOG_ERR, "ioctlsocket(FIONBIO) fails: %m");
exit(1); /* Windows NT - set socket in non-blocking mode */
}
}
#endif /* SYS_WINNT */
if (connect(sockfd, (struct sockaddr *)&saddr, sizeof(saddr)) == -1) {
msyslog(LOG_ERR, "openntp: connect() failed: %m");
exit(1);
}
}
/*
* tell_ntpd: Tell ntpd what we discovered.
*/
static int
tell_ntpd(
struct info_dns_assoc *conf
)
{
fd_set fdset;
struct timeval tvout;
struct req_pkt reqpkt;
l_fp ts;
int n;
#ifdef SYS_WINNT
HANDLE hReadWriteEvent = NULL;
BOOL ret;
DWORD NumberOfBytesWritten, NumberOfBytesRead, dwWait;
OVERLAPPED overlap;
#endif /* SYS_WINNT */
checkparent(); /* make sure our guy is still running */
if (sockfd < 0)
openntp();
#ifdef SYS_WINNT
hReadWriteEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
#endif /* SYS_WINNT */
/*
* Try to clear out any previously received traffic so it
* doesn't fool us. Note the socket is nonblocking.
*/
tvout.tv_sec = 0;
tvout.tv_usec = 0;
FD_ZERO(&fdset);
FD_SET(sockfd, &fdset);
while (select(sockfd + 1, &fdset, (fd_set *)0, (fd_set *)0, &tvout) >
0) {
recv(sockfd, (char *)&reqpkt, REQ_LEN_MAC, 0);
FD_ZERO(&fdset);
FD_SET(sockfd, &fdset);
}
/*
* Make up a request packet with the configuration info
*/
memset((char *)&reqpkt, 0, sizeof(reqpkt));
reqpkt.rm_vn_mode = RM_VN_MODE(0, 0, 0);
reqpkt.auth_seq = AUTH_SEQ(1, 0); /* authenticated, no seq */
reqpkt.implementation = IMPL_XNTPD; /* local implementation */
reqpkt.request = REQ_HOSTNAME_ASSOCID; /* Hostname for associd */
reqpkt.err_nitems = ERR_NITEMS(0, 1); /* one item */
reqpkt.mbz_itemsize = MBZ_ITEMSIZE(sizeof(struct info_dns_assoc));
memmove(reqpkt.data, (char *)conf, sizeof(struct info_dns_assoc));
reqpkt.keyid = htonl(req_keyid);
get_systime(&ts);
L_ADDUF(&ts, SKEWTIME);
HTONL_FP(&ts, &reqpkt.tstamp);
n = 0;
if (sys_authenticate)
n = authencrypt(req_keyid, (u_int32 *)&reqpkt, REQ_LEN_NOMAC);
/*
* Done. Send it.
*/
#ifndef SYS_WINNT
n = send(sockfd, (char *)&reqpkt, (unsigned)(REQ_LEN_NOMAC + n), 0);
if (n < 0) {
msyslog(LOG_ERR, "send to NTP server failed: %m");
return 0; /* maybe should exit */
}
#else
/* In the NT world, documentation seems to indicate that there
* exist _write and _read routines that can be used to do blocking
* I/O on sockets. Problem is these routines require a socket
* handle obtained through the _open_osf_handle C run-time API
* of which there is no explanation in the documentation. We need
* nonblocking write's and read's anyway for our purpose here.
* We're therefore forced to deviate a little bit from the Unix
* model here and use the ReadFile and WriteFile Win32 I/O API's
* on the socket
*/
overlap.Offset = overlap.OffsetHigh = (DWORD)0;
overlap.hEvent = hReadWriteEvent;
ret = WriteFile((HANDLE)sockfd, (char *)&reqpkt, REQ_LEN_NOMAC + n,
(LPDWORD)&NumberOfBytesWritten, (LPOVERLAPPED)&overlap);
if ((ret == FALSE) && (GetLastError() != ERROR_IO_PENDING)) {
msyslog(LOG_ERR, "send to NTP server failed: %m");
return 0;
}
dwWait = WaitForSingleObject(hReadWriteEvent, (DWORD) TIMEOUT_SEC * 1000);
if ((dwWait == WAIT_FAILED) || (dwWait == WAIT_TIMEOUT)) {
if (dwWait == WAIT_FAILED)
msyslog(LOG_ERR, "WaitForSingleObject failed: %m");
return 0;
}
#endif /* SYS_WINNT */
/*
* Wait for a response. A weakness of the mode 7 protocol used
* is that there is no way to associate a response with a
* particular request, i.e. the response to this configuration
* request is indistinguishable from that to any other. I should
* fix this some day. In any event, the time out is fairly
* pessimistic to make sure that if an answer is coming back
* at all, we get it.
*/
for (;;) {
FD_ZERO(&fdset);
FD_SET(sockfd, &fdset);
tvout.tv_sec = TIMEOUT_SEC;
tvout.tv_usec = TIMEOUT_USEC;
n = select(sockfd + 1, &fdset, (fd_set *)0,
(fd_set *)0, &tvout);
if (n < 0)
{
msyslog(LOG_ERR, "select() fails: %m");
return 0;
}
else if (n == 0)
{
if(debug)
msyslog(LOG_INFO, "select() returned 0.");
return 0;
}
#ifndef SYS_WINNT
n = recv(sockfd, (char *)&reqpkt, REQ_LEN_MAC, 0);
if (n <= 0) {
if (n < 0) {
msyslog(LOG_ERR, "recv() fails: %m");
return 0;
}
continue;
}
#else /* Overlapped I/O used on non-blocking sockets on Windows NT */
ret = ReadFile((HANDLE)sockfd, (char *)&reqpkt, (DWORD)REQ_LEN_MAC,
(LPDWORD)&NumberOfBytesRead, (LPOVERLAPPED)&overlap);
if ((ret == FALSE) && (GetLastError() != ERROR_IO_PENDING)) {
msyslog(LOG_ERR, "ReadFile() fails: %m");
return 0;
}
dwWait = WaitForSingleObject(hReadWriteEvent, (DWORD) TIMEOUT_SEC * 1000);
if ((dwWait == WAIT_FAILED) || (dwWait == WAIT_TIMEOUT)) {
if (dwWait == WAIT_FAILED) {
msyslog(LOG_ERR, "WaitForSingleObject fails: %m");
return 0;
}
continue;
}
n = NumberOfBytesRead;
#endif /* SYS_WINNT */
/*
* Got one. Check through to make sure it is what
* we expect.
*/
if (n < RESP_HEADER_SIZE) {
msyslog(LOG_ERR, "received runt response (%d octets)",
n);
continue;
}
if (!ISRESPONSE(reqpkt.rm_vn_mode)) {
#ifdef DEBUG
if (debug > 1)
msyslog(LOG_INFO, "received non-response packet");
#endif
continue;
}
if (ISMORE(reqpkt.rm_vn_mode)) {
#ifdef DEBUG
if (debug > 1)
msyslog(LOG_INFO, "received fragmented packet");
#endif
continue;
}
if ( ( (INFO_VERSION(reqpkt.rm_vn_mode) < 2)
|| (INFO_VERSION(reqpkt.rm_vn_mode) > NTP_VERSION))
|| INFO_MODE(reqpkt.rm_vn_mode) != MODE_PRIVATE) {
#ifdef DEBUG
if (debug > 1)
msyslog(LOG_INFO,
"version (%d/%d) or mode (%d/%d) incorrect",
INFO_VERSION(reqpkt.rm_vn_mode),
NTP_VERSION,
INFO_MODE(reqpkt.rm_vn_mode),
MODE_PRIVATE);
#endif
continue;
}
if (INFO_SEQ(reqpkt.auth_seq) != 0) {
#ifdef DEBUG
if (debug > 1)
msyslog(LOG_INFO,
"nonzero sequence number (%d)",
INFO_SEQ(reqpkt.auth_seq));
#endif
continue;
}
if (reqpkt.implementation != IMPL_XNTPD ||
reqpkt.request != REQ_HOSTNAME_ASSOCID) {
#ifdef DEBUG
if (debug > 1)
msyslog(LOG_INFO,
"implementation (%d/%d) or request (%d/%d) incorrect",
reqpkt.implementation, IMPL_XNTPD,
reqpkt.request, REQ_HOSTNAME_ASSOCID);
#endif
continue;
}
if (INFO_NITEMS(reqpkt.err_nitems) != 0 ||
INFO_MBZ(reqpkt.mbz_itemsize) != 0 ||
INFO_ITEMSIZE(reqpkt.mbz_itemsize) != 0) {
#ifdef DEBUG
if (debug > 1)
msyslog(LOG_INFO,
"nitems (%d) mbz (%d) or itemsize (%d) nonzero",
INFO_NITEMS(reqpkt.err_nitems),
INFO_MBZ(reqpkt.mbz_itemsize),
INFO_ITEMSIZE(reqpkt.mbz_itemsize));
#endif
continue;
}
n = INFO_ERR(reqpkt.err_nitems);
switch (n) {
case INFO_OKAY:
/* success */
return 1;
case INFO_ERR_IMPL:
msyslog(LOG_ERR,
"server reports implementation mismatch!!");
return 0;
case INFO_ERR_REQ:
msyslog(LOG_ERR,
"server claims configuration request is unknown");
return 0;
case INFO_ERR_FMT:
msyslog(LOG_ERR,
"server indicates a format error occurred(!!)");
return 0;
case INFO_ERR_NODATA:
msyslog(LOG_ERR,
"server indicates no data available (shouldn't happen)");
return 0;
case INFO_ERR_AUTH:
msyslog(LOG_ERR,
"server returns a permission denied error");
return 0;
default:
msyslog(LOG_ERR,
"server returns unknown error code %d", n);
return 0;
}
}
}
/*
* doconfigure - attempt to resolve names/addresses
*/
static void
doconfigure(
int dores
)
{
register struct dns_entry *de;
register struct dns_entry *deremove;
char *done_msg = "";
de = dns_entries;
while (de != NULL) {
#ifdef DEBUG
if (debug > 1) {
struct in_addr si;
si.s_addr = de->de_peeraddr;
msyslog(LOG_INFO,
"doconfigure: name: <%s> peeraddr: %s",
de->de_hostname, inet_ntoa(si));
}
#endif
if (dores && (de->de_hostname[0] == 0 || de->de_peeraddr == 0)) {
findhostaddr(de);
}
switch (de->de_done & DE_RESULT) {
case DE_PENDING:
done_msg = "";
break;
case DE_GOT:
done_msg = "succeeded";
break;
case DE_FAIL:
done_msg = "failed";
break;
default:
done_msg = "(error - shouldn't happen)";
break;
}
if (done_msg[0]) {
/* Send the answer */
if (tell_ntpd(&de->de_info)) {
struct in_addr si;
si.s_addr = de->de_peeraddr;
#ifdef DEBUG
if (debug > 1) {
msyslog(LOG_INFO,
"DNS resolution on <%s>/%s %s",
de->de_hostname, inet_ntoa(si),
done_msg);
}
#endif
deremove = de;
de = deremove->de_next;
removeentry(deremove);
}
} else {
de = de->de_next;
}
}
}