usr.sbin/ypserv/yp_main.c

   1 /*
   2  * Copyright (c) 1995
   3  *      Bill Paul <wpaul@ctr.columbia.edu>.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by Bill Paul.
  16  * 4. Neither the name of the author nor the names of any co-contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  *
  32  * $FreeBSD: src/usr.sbin/ypserv/yp_main.c,v 1.21.2.3 2002/02/15 00:47:00 des Exp $
  33  * $DragonFly: src/usr.sbin/ypserv/yp_main.c,v 1.5 2005/11/24 22:23:02 swildner Exp $
  34  */
  35
  36 /*
  37  * ypserv startup function.
  38  * We need out own main() since we have to do some additional work
  39  * that rpcgen won't do for us. Most of this file was generated using
  40  * rpcgen.new, and later modified.
  41  */
  42
  43 #include "yp.h"
  44 #include <err.h>
  45 #include <errno.h>
  46 #include <memory.h>
  47 #include <stdio.h>
  48 #include <signal.h>
  49 #include <stdlib.h> /* getenv, exit */
  50 #include <string.h> /* strcmp */
  51 #include <syslog.h>
  52 #include <unistd.h>
  53 #include <rpc/pmap_clnt.h> /* for pmap_unset */
  54 #ifdef __cplusplus
  55 #include <sysent.h> /* getdtablesize, open */
  56 #endif /* __cplusplus */
  57 #include <sys/socket.h>
  58 #include <netinet/in.h>
  59 #include <sys/wait.h>
  60 #include "yp_extern.h"
  61 #include <rpc/rpc.h>
  62
  63 #ifndef SIG_PF
  64 #define SIG_PF void(*)(int)
  65 #endif
  66
  67 #define _RPCSVC_CLOSEDOWN 120
  68 int _rpcpmstart;                /* Started by a port monitor ? */
  69 static int _rpcfdtype;
  70                  /* Whether Stream or Datagram ? */
  71         /* States a server can be in wrt request */
  72
  73 #define _IDLE 0
  74 #define _SERVED 1
  75 #define _SERVING 2
  76
  77 extern void ypprog_1(struct svc_req *, SVCXPRT *);
  78 extern void ypprog_2(struct svc_req *, SVCXPRT *);
  79 extern int _rpc_dtablesize(void);
  80 extern int _rpcsvcstate;         /* Set when a request is serviced */
  81 char *progname = "ypserv";
  82 char *yp_dir = _PATH_YP;
  83 /*int debug = 0;*/
  84 int do_dns = 0;
  85 int resfd;
  86
  87 static void
  88 _msgout(char *msg)
  89 {
  90         if (debug) {
  91                 if (_rpcpmstart)
  92                         syslog(LOG_ERR, "%s", msg);
  93                 else
  94                         warnx("%s", msg);
  95         } else
  96                 syslog(LOG_ERR, "%s", msg);
  97 }
  98
  99 pid_t   yp_pid;
 100
 101 static void
 102 yp_svc_run(void)
 103 {
 104 #ifdef FD_SETSIZE
 105         fd_set readfds;
 106 #else
 107         int readfds;
 108 #endif /* def FD_SETSIZE */
 109         extern int forked;
 110         int fd_setsize = _rpc_dtablesize();
 111         struct timeval timeout;
 112
 113         /* Establish the identity of the parent ypserv process. */
 114         yp_pid = getpid();
 115
 116         for (;;) {
 117 #ifdef FD_SETSIZE
 118                 readfds = svc_fdset;
 119 #else
 120                 readfds = svc_fds;
 121 #endif /* def FD_SETSIZE */
 122
 123                 FD_SET(resfd, &readfds);
 124
 125                 timeout.tv_sec = RESOLVER_TIMEOUT;
 126                 timeout.tv_usec = 0;
 127                 switch (select(fd_setsize, &readfds, NULL, NULL,
 128                                &timeout)) {
 129                 case -1:
 130                         if (errno == EINTR) {
 131                                 continue;
 132                         }
 133                         warn("svc_run: - select failed");
 134                         return;
 135                 case 0:
 136                         if (getpid() == yp_pid)
 137                                 yp_prune_dnsq();
 138                         break;
 139                 default:
 140                         if (getpid() == yp_pid) {
 141                                 if (FD_ISSET(resfd, &readfds)) {
 142                                         yp_run_dnsq();
 143                                         FD_CLR(resfd, &readfds);
 144                                 }
 145                                 svc_getreqset(&readfds);
 146                         }
 147                 }
 148                 if (yp_pid != getpid())
 149                         _exit(0);
 150         }
 151 }
 152
 153 static void
 154 unregister(void)
 155 {
 156         pmap_unset(YPPROG, YPVERS);
 157         pmap_unset(YPPROG, YPOLDVERS);
 158 }
 159
 160 static void
 161 reaper(int sig)
 162 {
 163         int status;
 164         int saved_errno;
 165
 166         saved_errno = errno;
 167
 168         if (sig == SIGHUP) {
 169                 load_securenets();
 170 #ifdef DB_CACHE
 171                 yp_flush_all();
 172 #endif
 173                 errno = saved_errno;
 174                 return;
 175         }
 176
 177         if (sig == SIGCHLD) {
 178                 while (wait3(&status, WNOHANG, NULL) > 0)
 179                         children--;
 180         } else {
 181                 unregister();
 182                 exit(0);
 183         }
 184         errno = saved_errno;
 185         return;
 186 }
 187
 188 static void
 189 usage(void)
 190 {
 191         fprintf(stderr, "usage: ypserv [-h] [-d] [-n] [-p path]\n");
 192         exit(1);
 193 }
 194
 195 static void
 196 closedown(int sig)
 197 {
 198         if (_rpcsvcstate == _IDLE) {
 199                 extern fd_set svc_fdset;
 200                 static int size;
 201                 int i, openfd;
 202
 203                 if (_rpcfdtype == SOCK_DGRAM) {
 204                         unregister();
 205                         exit(0);
 206                 }
 207                 if (size == 0) {
 208                         size = getdtablesize();
 209                 }
 210                 for (i = 0, openfd = 0; i < size && openfd < 2; i++)
 211                         if (FD_ISSET(i, &svc_fdset))
 212                                 openfd++;
 213                 if (openfd <= 1) {
 214                         unregister();
 215                         exit(0);
 216                 }
 217         }
 218         if (_rpcsvcstate == _SERVED)
 219                 _rpcsvcstate = _IDLE;
 220
 221         signal(SIGALRM, (SIG_PF)closedown);
 222         alarm(_RPCSVC_CLOSEDOWN / 2);
 223 }
 224
 225 int
 226 main(int argc, char **argv)
 227 {
 228         SVCXPRT *transp = NULL;
 229         int sock;
 230         int proto = 0;
 231         struct sockaddr_in saddr;
 232         int asize = sizeof(saddr);
 233         int ch;
 234
 235         while ((ch = getopt(argc, argv, "hdnp:")) != -1) {
 236                 switch (ch) {
 237                 case 'd':
 238                         debug = ypdb_debug = 1;
 239                         break;
 240                 case 'n':
 241                         do_dns = 1;
 242                         break;
 243                 case 'p':
 244                         yp_dir = optarg;
 245                         break;
 246                 case 'h':
 247                 default:
 248                         usage();
 249                 }
 250         }
 251
 252         load_securenets();
 253         yp_init_resolver();
 254 #ifdef DB_CACHE
 255         yp_init_dbs();
 256 #endif
 257         if (getsockname(0, (struct sockaddr *)&saddr, &asize) == 0) {
 258                 int ssize = sizeof (int);
 259
 260                 if (saddr.sin_family != AF_INET)
 261                         exit(1);
 262                 if (getsockopt(0, SOL_SOCKET, SO_TYPE,
 263                                 (char *)&_rpcfdtype, &ssize) == -1)
 264                         exit(1);
 265                 sock = 0;
 266                 _rpcpmstart = 1;
 267                 proto = 0;
 268                 openlog("ypserv", LOG_PID, LOG_DAEMON);
 269         } else {
 270                 if (!debug) {
 271                         if (daemon(0,0)) {
 272                                 err(1,"cannot fork");
 273                         }
 274                         openlog("ypserv", LOG_PID, LOG_DAEMON);
 275                 }
 276                 sock = RPC_ANYSOCK;
 277                 pmap_unset(YPPROG, YPVERS);
 278                 pmap_unset(YPPROG, 1);
 279         }
 280
 281         if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_DGRAM)) {
 282                 transp = svcudp_create(sock);
 283                 if (transp == NULL) {
 284                         _msgout("cannot create udp service");
 285                         exit(1);
 286                 }
 287                 if (!_rpcpmstart)
 288                         proto = IPPROTO_UDP;
 289                 if (!svc_register(transp, YPPROG, YPOLDVERS, ypprog_1, proto)) {
 290                         _msgout("unable to register (YPPROG, YPOLDVERS, udp)");
 291                         exit(1);
 292                 }
 293                 if (!svc_register(transp, YPPROG, YPVERS, ypprog_2, proto)) {
 294                         _msgout("unable to register (YPPROG, YPVERS, udp)");
 295                         exit(1);
 296                 }
 297         }
 298
 299         if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_STREAM)) {
 300                 transp = svctcp_create(sock, 0, 0);
 301                 if (transp == NULL) {
 302                         _msgout("cannot create tcp service");
 303                         exit(1);
 304                 }
 305                 if (!_rpcpmstart)
 306                         proto = IPPROTO_TCP;
 307                 if (!svc_register(transp, YPPROG, YPOLDVERS, ypprog_1, proto)) {
 308                         _msgout("unable to register (YPPROG, YPOLDVERS, tcp)");
 309                         exit(1);
 310                 }
 311                 if (!svc_register(transp, YPPROG, YPVERS, ypprog_2, proto)) {
 312                         _msgout("unable to register (YPPROG, YPVERS, tcp)");
 313                         exit(1);
 314                 }
 315         }
 316
 317         if (transp == (SVCXPRT *)NULL) {
 318                 _msgout("could not create a handle");
 319                 exit(1);
 320         }
 321         if (_rpcpmstart) {
 322                 signal(SIGALRM, (SIG_PF)closedown);
 323                 alarm(_RPCSVC_CLOSEDOWN / 2);
 324         }
 325 /*
 326  * Make sure SIGPIPE doesn't blow us away while servicing TCP
 327  * connections.
 328  */
 329         signal(SIGPIPE, SIG_IGN);
 330         signal(SIGCHLD, (SIG_PF) reaper);
 331         signal(SIGTERM, (SIG_PF) reaper);
 332         signal(SIGINT, (SIG_PF) reaper);
 333         signal(SIGHUP, (SIG_PF) reaper);
 334         yp_svc_run();
 335         _msgout("svc_run returned");
 336         exit(1);
 337         /* NOTREACHED */
 338 }