libexec/rpc.rwalld/rwalld.c

   1 /* $NetBSD: rwalld.c,v 1.19 2003/07/26 19:32:09 salo Exp $ */
   2
   3 /*
   4  * Copyright (c) 1993 Christopher G. Demetriou
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgement:
  17  *          This product includes software developed for the
  18  *          NetBSD Project.  See http://www.NetBSD.org/ for
  19  *          information about NetBSD.
  20  * 4. The name of the author may not be used to endorse or promote products
  21  *    derived from this software without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  26  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  33  *
  34  * <<Id: LICENSE,v 1.2 2000/06/14 15:57:33 cgd Exp>>
  35  */
  36
  37 #include <sys/cdefs.h>
  38 #ifndef lint
  39 __RCSID("$NetBSD: rwalld.c,v 1.19 2003/07/26 19:32:09 salo Exp $");
  40 #endif /* not lint */
  41
  42 #include <unistd.h>
  43 #include <stdlib.h>
  44 #include <sys/types.h>
  45 #include <pwd.h>
  46 #include <stdio.h>
  47 #include <string.h>
  48 #include <syslog.h>
  49 #include <errno.h>
  50 #include <sys/socket.h>
  51 #include <signal.h>
  52 #include <sys/wait.h>
  53 #include <rpc/rpc.h>
  54 #include <rpcsvc/rwall.h>
  55
  56 #ifdef OSF
  57 #define WALL_CMD "/usr/sbin/wall"
  58 #else
  59 #define WALL_CMD "/usr/bin/wall -n"
  60 #endif
  61
  62 static int from_inetd = 1;
  63
  64 static void cleanup(int);
  65 static void wallprog_1(struct svc_req *, SVCXPRT *);
  66
  67 int main(int, char *[]);
  68
  69 static void
  70 cleanup(int n)
  71 {
  72
  73         (void)rpcb_unset(WALLPROG, WALLVERS, NULL);
  74         exit(0);
  75 }
  76
  77 int
  78 main(int argc, char *argv[])
  79 {
  80         SVCXPRT *transp;
  81         struct sockaddr_storage from;
  82         socklen_t fromlen;
  83
  84         if (geteuid() == 0) {
  85                 struct passwd *pep = getpwnam("nobody");
  86                 if (pep)
  87                         setuid(pep->pw_uid);
  88                 else
  89                         setuid(getuid());
  90         }
  91
  92         /*
  93          * See if inetd started us
  94          */
  95         fromlen = sizeof(from);
  96         if (getsockname(0, (struct sockaddr *)&from, &fromlen) < 0)
  97                 from_inetd = 0;
  98
  99         if (!from_inetd) {
 100                 daemon(0, 0);
 101
 102                 (void) rpcb_unset(WALLPROG, WALLVERS, NULL);
 103
 104                 (void) signal(SIGINT, cleanup);
 105                 (void) signal(SIGTERM, cleanup);
 106                 (void) signal(SIGHUP, cleanup);
 107         }
 108
 109         openlog("rpc.rwalld", LOG_PID, LOG_DAEMON);
 110
 111         if (from_inetd) {
 112                 transp = svc_dg_create(0, 0, 0);
 113                 if (transp == NULL) {
 114                         syslog(LOG_ERR, "cannot create udp service.");
 115                         exit(1);
 116                 }
 117                 if (!svc_reg(transp, WALLPROG, WALLVERS, wallprog_1, NULL)) {
 118                         syslog(LOG_ERR, "unable to register "
 119                             "(WALLPROG, WALLVERS).");
 120                         exit(1);
 121                 }
 122         } else {
 123                 if (!svc_create(wallprog_1, WALLPROG, WALLVERS, "udp")) {
 124                         syslog(LOG_ERR, "unable to create "
 125                             "(WALLPROG, WALLVERS.)");
 126                         exit(1);
 127                 }
 128         }
 129
 130         svc_run();
 131         syslog(LOG_ERR, "svc_run returned");
 132         exit(1);
 133
 134 }
 135
 136 void *
 137 wallproc_wall_1_svc(char **s, struct svc_req *rqstp)
 138 {
 139         FILE *pfp;
 140
 141         pfp = popen(WALL_CMD, "w");
 142         if (pfp != NULL) {
 143                 fprintf(pfp, "\007\007%s", *s);
 144                 pclose(pfp);
 145         }
 146
 147         return (*s);
 148 }
 149
 150 static void
 151 wallprog_1(struct svc_req *rqstp, SVCXPRT *transp)
 152 {
 153         union {
 154                 char *wallproc_wall_1_arg;
 155         } argument;
 156         char *result;
 157         xdrproc_t xdr_argument, xdr_result;
 158         char *(*local) __P((char **, struct svc_req *));
 159
 160         switch (rqstp->rq_proc) {
 161         case NULLPROC:
 162                 (void)svc_sendreply(transp, xdr_void, (char *)NULL);
 163                 goto leave;
 164
 165         case WALLPROC_WALL:
 166                 xdr_argument = (xdrproc_t)xdr_wrapstring;
 167                 xdr_result = (xdrproc_t)xdr_void;
 168                 local = (char *(*) __P((char **, struct svc_req *)))
 169                         wallproc_wall_1_svc;
 170                 break;
 171
 172         default:
 173                 svcerr_noproc(transp);
 174                 goto leave;
 175         }
 176         memset((char *)&argument, 0, sizeof(argument));
 177         if (!svc_getargs(transp, xdr_argument, (caddr_t)&argument)) {
 178                 svcerr_decode(transp);
 179                 goto leave;
 180         }
 181         result = (*local)((char **)&argument, rqstp);
 182         if (result != NULL && !svc_sendreply(transp, xdr_result, result)) {
 183                 svcerr_systemerr(transp);
 184         }
 185         if (!svc_freeargs(transp, xdr_argument, (caddr_t)&argument)) {
 186                 syslog(LOG_ERR, "unable to free arguments");
 187                 exit(1);
 188         }
 189 leave:
 190         if (from_inetd)
 191                 exit(0);
 192 }