Home | History | Annotate | Line # | Download | only in rpc.rwalld
rwalld.c revision 1.5 
      1 /*
      2  * Copyright (c) 1993 Christopher G. Demetriou
      3  * 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. The name of the author may not be used to endorse or promote
     14  *    products derived from this software without specific prior written
     15  *    permission.
     16  *
     17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
     18  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
     19  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
     21  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     27  * SUCH DAMAGE.
     28  */
     29 
     30 #ifndef lint
     31 static char rcsid[] = "$Id: rwalld.c,v 1.5 1995/01/13 18:51:39 mycroft Exp $";
     32 #endif /* not lint */
     33 
     34 #include <unistd.h>
     35 #include <sys/types.h>
     36 #include <pwd.h>
     37 #include <stdio.h>
     38 #include <string.h>
     39 #include <errno.h>
     40 #include <sys/socket.h>
     41 #include <signal.h>
     42 #include <sys/wait.h>
     43 #include <rpc/rpc.h>
     44 #include <rpcsvc/rwall.h>
     45 
     46 #ifdef OSF
     47 #define WALL_CMD "/usr/sbin/wall"
     48 #else
     49 #define WALL_CMD "/usr/bin/wall -n"
     50 #endif
     51 
     52 void wallprog_1();
     53 
     54 int from_inetd = 1;
     55 
     56 void
     57 cleanup()
     58 {
     59 	(void) pmap_unset(WALLPROG, WALLVERS);
     60 	exit(0);
     61 }
     62 
     63 main(argc, argv)
     64 	int argc;
     65 	char *argv[];
     66 {
     67 	SVCXPRT *transp;
     68 	int sock = 0;
     69 	int proto = 0;
     70 	struct sockaddr_in from;
     71 	int fromlen;
     72 
     73 	if (geteuid() == 0) {
     74 		struct passwd *pep = getpwnam("nobody");
     75 		if (pep)
     76 			setuid(pep->pw_uid);
     77 		else
     78 			setuid(getuid());
     79 	}
     80 
     81 	/*
     82 	 * See if inetd started us
     83 	 */
     84 	fromlen = sizeof(from);
     85 	if (getsockname(0, (struct sockaddr *)&from, &fromlen) < 0) {
     86 		from_inetd = 0;
     87 		sock = RPC_ANYSOCK;
     88 		proto = IPPROTO_UDP;
     89 	}
     90 
     91 	if (!from_inetd) {
     92 		daemon(0, 0);
     93 
     94 		(void) pmap_unset(WALLPROG, WALLVERS);
     95 
     96 		(void) signal(SIGINT, cleanup);
     97 		(void) signal(SIGTERM, cleanup);
     98 		(void) signal(SIGHUP, cleanup);
     99 	}
    100 
    101 	openlog("rpc.rwalld", LOG_CONS|LOG_PID, LOG_DAEMON);
    102 
    103 	transp = svcudp_create(sock);
    104 	if (transp == NULL) {
    105 		syslog(LOG_ERR, "cannot create udp service.");
    106 		exit(1);
    107 	}
    108 	if (!svc_register(transp, WALLPROG, WALLVERS, wallprog_1, proto)) {
    109 		syslog(LOG_ERR, "unable to register (WALLPROG, WALLVERS, %s).", proto?"udp":"(inetd)");
    110 		exit(1);
    111 	}
    112 
    113 	svc_run();
    114 	syslog(LOG_ERR, "svc_run returned");
    115 	exit(1);
    116 
    117 }
    118 
    119 void *
    120 wallproc_wall_1(s)
    121 	char **s;
    122 {
    123 	FILE *pfp;
    124 
    125 	pfp = popen(WALL_CMD, "w");
    126 	if (pfp != NULL) {
    127 		fprintf(pfp, "\007\007%s", *s);
    128 		pclose(pfp);
    129 	}
    130 
    131 	return (NULL);
    132 }
    133 
    134 void
    135 wallprog_1(rqstp, transp)
    136 	struct svc_req *rqstp;
    137 	SVCXPRT *transp;
    138 {
    139 	union {
    140 		char *wallproc_wall_1_arg;
    141 	} argument;
    142 	char *result;
    143 	bool_t (*xdr_argument)(), (*xdr_result)();
    144 	char *(*local)();
    145 
    146 	switch (rqstp->rq_proc) {
    147 	case NULLPROC:
    148 		(void)svc_sendreply(transp, xdr_void, (char *)NULL);
    149 		goto leave;
    150 
    151 	case WALLPROC_WALL:
    152 		xdr_argument = xdr_wrapstring;
    153 		xdr_result = xdr_void;
    154 		local = (char *(*)()) wallproc_wall_1;
    155 		break;
    156 
    157 	default:
    158 		svcerr_noproc(transp);
    159 		goto leave;
    160 	}
    161 	bzero((char *)&argument, sizeof(argument));
    162 	if (!svc_getargs(transp, xdr_argument, (caddr_t)&argument)) {
    163 		svcerr_decode(transp);
    164 		goto leave;
    165 	}
    166 	result = (*local)(&argument, rqstp);
    167 	if (result != NULL && !svc_sendreply(transp, xdr_result, result)) {
    168 		svcerr_systemerr(transp);
    169 	}
    170 	if (!svc_freeargs(transp, xdr_argument, (caddr_t)&argument)) {
    171 		log(LOG_ERR, "unable to free arguments");
    172 		exit(1);
    173 	}
    174 leave:
    175 	if (from_inetd)
    176 		exit(0);
    177 }
    178