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 1.29 2008/02/03 17:39:37 matteo Exp $
  33  */
  34
  35 /*
  36  * ypserv startup function.
  37  * We need out own main() since we have to do some additional work
  38  * that rpcgen won't do for us. Most of this file was generated using
  39  * rpcgen.new, and later modified.
  40  */
  41
  42 #include "yp.h"
  43 #include <err.h>
  44 #include <errno.h>
  45 #include <memory.h>
  46 #include <stdio.h>
  47 #include <signal.h>
  48 #include <stdlib.h> /* getenv, exit */
  49 #include <string.h> /* strcmp */
  50 #include <syslog.h>
  51 #include <unistd.h>
  52 #include <rpc/pmap_clnt.h> /* for pmap_unset */
  53 #ifdef __cplusplus
  54 #include <sysent.h> /* getdtablesize, open */
  55 #endif /* __cplusplus */
  56 #include <sys/socket.h>
  57 #include <netinet/in.h>
  58 #include <sys/wait.h>
  59 #include "yp_extern.h"
  60 #include <rpc/rpc.h>
  61
  62 #ifndef SIG_PF
  63 #define SIG_PF void(*)(int)
  64 #endif
  65
  66 #define _RPCSVC_CLOSEDOWN 120
  67 int _rpcpmstart;                /* Started by a port monitor ? */
  68 static int _rpcfdtype;
  69                  /* Whether Stream or Datagram ? */
  70         /* States a server can be in wrt request */
  71
  72 #define _IDLE 0
  73 #define _SERVED 1
  74 #define _SERVING 2
  75
  76 extern void ypprog_1(struct svc_req *, SVCXPRT *);
  77 extern void ypprog_2(struct svc_req *, SVCXPRT *);
  78 extern int _rpc_dtablesize(void);
  79 extern int _rpcsvcstate;         /* Set when a request is serviced */
  80 char *progname = "ypserv";
  81 const char *yp_dir = _PATH_YP;
  82 int debug = 0;
  83 int do_dns = 0;
  84 int resfd;
  85
  86 struct socktype {
  87         const char *st_name;
  88         int        st_type;
  89 };
  90 static struct socktype stlist[] = {
  91         { "tcp", SOCK_STREAM },
  92         { "udp", SOCK_DGRAM },
  93         { NULL, 0 }
  94 };
  95
  96 static void
  97 _msgout(char *msg)
  98 {
  99         if (debug) {
 100                 if (_rpcpmstart)
 101                         syslog(LOG_ERR, "%s", msg);
 102                 else
 103                         warnx("%s", msg);
 104         } else
 105                 syslog(LOG_ERR, "%s", msg);
 106 }
 107
 108 pid_t   yp_pid;
 109
 110 static void
 111 yp_svc_run(void)
 112 {
 113 #ifdef FD_SETSIZE
 114         fd_set readfds;
 115 #else
 116         int readfds;
 117 #endif /* def FD_SETSIZE */
 118         int fd_setsize = _rpc_dtablesize();
 119         struct timeval timeout;
 120
 121         /* Establish the identity of the parent ypserv process. */
 122         yp_pid = getpid();
 123
 124         for (;;) {
 125 #ifdef FD_SETSIZE
 126                 readfds = svc_fdset;
 127 #else
 128                 readfds = svc_fds;
 129 #endif /* def FD_SETSIZE */
 130
 131                 FD_SET(resfd, &readfds);
 132
 133                 timeout.tv_sec = RESOLVER_TIMEOUT;
 134                 timeout.tv_usec = 0;
 135                 switch (select(fd_setsize, &readfds, NULL, NULL,
 136                                &timeout)) {
 137                 case -1:
 138                         if (errno == EINTR) {
 139                                 continue;
 140                         }
 141                         warn("svc_run: - select failed");
 142                         return;
 143                 case 0:
 144                         if (getpid() == yp_pid)
 145                                 yp_prune_dnsq();
 146                         break;
 147                 default:
 148                         if (getpid() == yp_pid) {
 149                                 if (FD_ISSET(resfd, &readfds)) {
 150                                         yp_run_dnsq();
 151                                         FD_CLR(resfd, &readfds);
 152                                 }
 153                                 svc_getreqset(&readfds);
 154                         }
 155                 }
 156                 if (yp_pid != getpid())
 157                         _exit(0);
 158         }
 159 }
 160
 161 static void
 162 unregister(void)
 163 {
 164         pmap_unset(YPPROG, YPVERS);
 165         pmap_unset(YPPROG, YPOLDVERS);
 166 }
 167
 168 static void
 169 reaper(int sig)
 170 {
 171         int status;
 172         int saved_errno;
 173
 174         saved_errno = errno;
 175
 176         if (sig == SIGHUP) {
 177                 load_securenets();
 178 #ifdef DB_CACHE
 179                 yp_flush_all();
 180 #endif
 181                 errno = saved_errno;
 182                 return;
 183         }
 184
 185         if (sig == SIGCHLD) {
 186                 while (wait3(&status, WNOHANG, NULL) > 0)
 187                         children--;
 188         } else {
 189                 unregister();
 190                 exit(0);
 191         }
 192         errno = saved_errno;
 193         return;
 194 }
 195
 196 static void
 197 usage(void)
 198 {
 199         fprintf(stderr, "usage: ypserv [-h] [-d] [-n] [-p path] [-P port]\n");
 200         exit(1);
 201 }
 202
 203 static void
 204 closedown(int sig)
 205 {
 206         if (_rpcsvcstate == _IDLE) {
 207                 extern fd_set svc_fdset;
 208                 static int size;
 209                 int i, openfd;
 210
 211                 if (_rpcfdtype == SOCK_DGRAM) {
 212                         unregister();
 213                         exit(0);
 214                 }
 215                 if (size == 0) {
 216                         size = getdtablesize();
 217                 }
 218                 for (i = 0, openfd = 0; i < size && openfd < 2; i++)
 219                         if (FD_ISSET(i, &svc_fdset))
 220                                 openfd++;
 221                 if (openfd <= 1) {
 222                         unregister();
 223                         exit(0);
 224                 }
 225         }
 226         if (_rpcsvcstate == _SERVED)
 227                 _rpcsvcstate = _IDLE;
 228
 229         signal(SIGALRM, (SIG_PF)closedown);
 230         alarm(_RPCSVC_CLOSEDOWN / 2);
 231 }
 232
 233 int
 234 main(int argc, char *argv[])
 235 {
 236         SVCXPRT *transp = NULL;
 237         int sock;
 238         int proto = 0;
 239         struct sockaddr_in saddr;
 240         socklen_t asize = sizeof (saddr);
 241         int ch;
 242         in_port_t yp_port = 0;
 243         char *errstr;
 244         struct socktype *st;
 245
 246         while ((ch = getopt(argc, argv, "hdnp:P:")) != -1) {
 247                 switch (ch) {
 248                 case 'd':
 249                         debug = ypdb_debug = 1;
 250                         break;
 251                 case 'n':
 252                         do_dns = 1;
 253                         break;
 254                 case 'p':
 255                         yp_dir = optarg;
 256                         break;
 257                 case 'P':
 258                         yp_port = (in_port_t)strtonum(optarg, 1, 65535,
 259                             (const char **)&errstr);
 260                         if (yp_port == 0 && errstr != NULL) {
 261                                 _msgout("invalid port number provided");
 262                                 exit(1);
 263                         }
 264                         break;
 265                 case 'h':
 266                 default:
 267                         usage();
 268                 }
 269         }
 270
 271         load_securenets();
 272         yp_init_resolver();
 273 #ifdef DB_CACHE
 274         yp_init_dbs();
 275 #endif
 276         if (getsockname(0, (struct sockaddr *)&saddr, &asize) == 0) {
 277                 int ssize = sizeof (int);
 278
 279                 if (saddr.sin_family != AF_INET)
 280                         exit(1);
 281                 if (getsockopt(0, SOL_SOCKET, SO_TYPE,
 282                                 (char *)&_rpcfdtype, &ssize) == -1)
 283                         exit(1);
 284                 sock = 0;
 285                 _rpcpmstart = 1;
 286                 proto = 0;
 287                 openlog("ypserv", LOG_PID, LOG_DAEMON);
 288         } else {
 289                 if (!debug) {
 290                         if (daemon(0,0)) {
 291                                 err(1,"cannot fork");
 292                         }
 293                         openlog("ypserv", LOG_PID, LOG_DAEMON);
 294                 }
 295                 sock = RPC_ANYSOCK;
 296                 pmap_unset(YPPROG, YPVERS);
 297                 pmap_unset(YPPROG, 1);
 298         }
 299
 300         /*
 301          * Initialize TCP/UDP sockets.
 302          */
 303         memset((char *)&saddr, 0, sizeof(saddr));
 304         saddr.sin_family = AF_INET;
 305         saddr.sin_addr.s_addr = htonl(INADDR_ANY);
 306         saddr.sin_port = htons(yp_port);
 307         for (st = stlist; st->st_name != NULL; st++) {
 308                 /* Do not bind the socket if the user didn't specify a port */
 309                 if (yp_port == 0)
 310                         break;
 311
 312                 sock = socket(AF_INET, st->st_type, 0);
 313                 if (sock == -1) {
 314                         if ((asprintf(&errstr, "cannot create a %s socket",
 315                             st->st_name)) == -1)
 316                                 err(1, "unexpected failure in asprintf()");
 317                         _msgout(errstr);
 318                         free((void *)errstr);
 319                         exit(1);
 320                 }
 321                 if (bind(sock, (struct sockaddr *) &saddr, sizeof(saddr))
 322                     == -1) {
 323                         if ((asprintf(&errstr, "cannot bind %s socket",
 324                             st->st_name)) == -1)
 325                                 err(1, "unexpected failure in asprintf()");
 326                         _msgout(errstr);
 327                         free((void *)errstr);
 328                         exit(1);
 329                 }
 330                 errstr = NULL;
 331         }
 332
 333         if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_DGRAM)) {
 334                 transp = svcudp_create(sock);
 335                 if (transp == NULL) {
 336                         _msgout("cannot create udp service");
 337                         exit(1);
 338                 }
 339                 if (!_rpcpmstart)
 340                         proto = IPPROTO_UDP;
 341                 if (!svc_register(transp, YPPROG, YPOLDVERS, ypprog_1, proto)) {
 342                         _msgout("unable to register (YPPROG, YPOLDVERS, udp)");
 343                         exit(1);
 344                 }
 345                 if (!svc_register(transp, YPPROG, YPVERS, ypprog_2, proto)) {
 346                         _msgout("unable to register (YPPROG, YPVERS, udp)");
 347                         exit(1);
 348                 }
 349         }
 350
 351         if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_STREAM)) {
 352                 transp = svctcp_create(sock, 0, 0);
 353                 if (transp == NULL) {
 354                         _msgout("cannot create tcp service");
 355                         exit(1);
 356                 }
 357                 if (!_rpcpmstart)
 358                         proto = IPPROTO_TCP;
 359                 if (!svc_register(transp, YPPROG, YPOLDVERS, ypprog_1, proto)) {
 360                         _msgout("unable to register (YPPROG, YPOLDVERS, tcp)");
 361                         exit(1);
 362                 }
 363                 if (!svc_register(transp, YPPROG, YPVERS, ypprog_2, proto)) {
 364                         _msgout("unable to register (YPPROG, YPVERS, tcp)");
 365                         exit(1);
 366                 }
 367         }
 368
 369         if (transp == NULL) {
 370                 _msgout("could not create a handle");
 371                 exit(1);
 372         }
 373         if (_rpcpmstart) {
 374                 signal(SIGALRM, (SIG_PF)closedown);
 375                 alarm(_RPCSVC_CLOSEDOWN / 2);
 376         }
 377 /*
 378  * Make sure SIGPIPE doesn't blow us away while servicing TCP
 379  * connections.
 380  */
 381         signal(SIGPIPE, SIG_IGN);
 382         signal(SIGCHLD, (SIG_PF) reaper);
 383         signal(SIGTERM, (SIG_PF) reaper);
 384         signal(SIGINT, (SIG_PF) reaper);
 385         signal(SIGHUP, (SIG_PF) reaper);
 386         yp_svc_run();
 387         _msgout("svc_run returned");
 388         exit(1);
 389         /* NOTREACHED */
 390 }