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 1.4 2004/12/18 22:48:15 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 reaper(int sig)
 161 {
 162         int status;
 163         int saved_errno;
 164
 165         saved_errno = errno;
 166
 167         if (sig == SIGHUP) {
 168                 load_securenets();
 169 #ifdef DB_CACHE
 170                 yp_flush_all();
 171 #endif
 172                 errno = saved_errno;
 173                 return;
 174         }
 175
 176         if (sig == SIGCHLD) {
 177                 while (wait3(&status, WNOHANG, NULL) > 0)
 178                         children--;
 179         } else {
 180                 unregister();
 181                 exit(0);
 182         }
 183         errno = saved_errno;
 184         return;
 185 }
 186
 187 static void
 188 usage(void)
 189 {
 190         fprintf(stderr, "usage: ypserv [-h] [-d] [-n] [-p path]\n");
 191         exit(1);
 192 }
 193
 194 static void
 195 closedown(int sig)
 196 {
 197         if (_rpcsvcstate == _IDLE) {
 198                 extern fd_set svc_fdset;
 199                 static int size;
 200                 int i, openfd;
 201
 202                 if (_rpcfdtype == SOCK_DGRAM) {
 203                         unregister();
 204                         exit(0);
 205                 }
 206                 if (size == 0) {
 207                         size = getdtablesize();
 208                 }
 209                 for (i = 0, openfd = 0; i < size && openfd < 2; i++)
 210                         if (FD_ISSET(i, &svc_fdset))
 211                                 openfd++;
 212                 if (openfd <= 1) {
 213                         unregister();
 214                         exit(0);
 215                 }
 216         }
 217         if (_rpcsvcstate == _SERVED)
 218                 _rpcsvcstate = _IDLE;
 219
 220         signal(SIGALRM, (SIG_PF)closedown);
 221         alarm(_RPCSVC_CLOSEDOWN / 2);
 222 }
 223
 224 int
 225 main(int argc, char **argv)
 226 {
 227         SVCXPRT *transp = NULL;
 228         int sock;
 229         int proto = 0;
 230         struct sockaddr_in saddr;
 231         int asize = sizeof(saddr);
 232         int ch;
 233
 234         while ((ch = getopt(argc, argv, "hdnp:")) != -1) {
 235                 switch (ch) {
 236                 case 'd':
 237                         debug = ypdb_debug = 1;
 238                         break;
 239                 case 'n':
 240                         do_dns = 1;
 241                         break;
 242                 case 'p':
 243                         yp_dir = optarg;
 244                         break;
 245                 case 'h':
 246                 default:
 247                         usage();
 248                 }
 249         }
 250
 251         load_securenets();
 252         yp_init_resolver();
 253 #ifdef DB_CACHE
 254         yp_init_dbs();
 255 #endif
 256         if (getsockname(0, (struct sockaddr *)&saddr, &asize) == 0) {
 257                 int ssize = sizeof (int);
 258
 259                 if (saddr.sin_family != AF_INET)
 260                         exit(1);
 261                 if (getsockopt(0, SOL_SOCKET, SO_TYPE,
 262                                 (char *)&_rpcfdtype, &ssize) == -1)
 263                         exit(1);
 264                 sock = 0;
 265                 _rpcpmstart = 1;
 266                 proto = 0;
 267                 openlog("ypserv", LOG_PID, LOG_DAEMON);
 268         } else {
 269                 if (!debug) {
 270                         if (daemon(0,0)) {
 271                                 err(1,"cannot fork");
 272                         }
 273                         openlog("ypserv", LOG_PID, LOG_DAEMON);
 274                 }
 275                 sock = RPC_ANYSOCK;
 276                 pmap_unset(YPPROG, YPVERS);
 277                 pmap_unset(YPPROG, 1);
 278         }
 279
 280         if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_DGRAM)) {
 281                 transp = svcudp_create(sock);
 282                 if (transp == NULL) {
 283                         _msgout("cannot create udp service");
 284                         exit(1);
 285                 }
 286                 if (!_rpcpmstart)
 287                         proto = IPPROTO_UDP;
 288                 if (!svc_register(transp, YPPROG, YPOLDVERS, ypprog_1, proto)) {
 289                         _msgout("unable to register (YPPROG, YPOLDVERS, udp)");
 290                         exit(1);
 291                 }
 292                 if (!svc_register(transp, YPPROG, YPVERS, ypprog_2, proto)) {
 293                         _msgout("unable to register (YPPROG, YPVERS, udp)");
 294                         exit(1);
 295                 }
 296         }
 297
 298         if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_STREAM)) {
 299                 transp = svctcp_create(sock, 0, 0);
 300                 if (transp == NULL) {
 301                         _msgout("cannot create tcp service");
 302                         exit(1);
 303                 }
 304                 if (!_rpcpmstart)
 305                         proto = IPPROTO_TCP;
 306                 if (!svc_register(transp, YPPROG, YPOLDVERS, ypprog_1, proto)) {
 307                         _msgout("unable to register (YPPROG, YPOLDVERS, tcp)");
 308                         exit(1);
 309                 }
 310                 if (!svc_register(transp, YPPROG, YPVERS, ypprog_2, proto)) {
 311                         _msgout("unable to register (YPPROG, YPVERS, tcp)");
 312                         exit(1);
 313                 }
 314         }
 315
 316         if (transp == (SVCXPRT *)NULL) {
 317                 _msgout("could not create a handle");
 318                 exit(1);
 319         }
 320         if (_rpcpmstart) {
 321                 signal(SIGALRM, (SIG_PF)closedown);
 322                 alarm(_RPCSVC_CLOSEDOWN / 2);
 323         }
 324 /*
 325  * Make sure SIGPIPE doesn't blow us away while servicing TCP
 326  * connections.
 327  */
 328         signal(SIGPIPE, SIG_IGN);
 329         signal(SIGCHLD, (SIG_PF) reaper);
 330         signal(SIGTERM, (SIG_PF) reaper);
 331         signal(SIGINT, (SIG_PF) reaper);
 332         signal(SIGHUP, (SIG_PF) reaper);
 333         yp_svc_run();
 334         _msgout("svc_run returned");
 335         exit(1);
 336         /* NOTREACHED */
 337 }