diff options
Diffstat (limited to 'libexec/rpc.rwalld/rwalld.c')
| -rw-r--r-- | libexec/rpc.rwalld/rwalld.c | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/libexec/rpc.rwalld/rwalld.c b/libexec/rpc.rwalld/rwalld.c new file mode 100644 index 000000000000..f265ff034e9c --- /dev/null +++ b/libexec/rpc.rwalld/rwalld.c @@ -0,0 +1,205 @@ +/*- + * SPDX-License-Identifier: BSD-3-Clause + * + * Copyright (c) 1993 Christopher G. Demetriou + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote + * products derived from this software without specific prior written + * permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS + * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED + * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY + * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +#include <err.h> +#include <pwd.h> +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <syslog.h> +#include <arpa/inet.h> +#include <rpc/rpc.h> +#include <rpcsvc/rwall.h> +#include <sys/socket.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <unistd.h> + +#ifdef OSF +#define WALL_CMD "/usr/sbin/wall" +#else +#define WALL_CMD "/usr/bin/wall -n" +#endif + +void wallprog_1(struct svc_req *rqstp, SVCXPRT *transp); +void possess(void); +void killkids(int sig); +static void usage(void) __dead2; + +int nodaemon = 0; +int from_inetd = 1; + +int +main(int argc, char *argv[]) +{ + SVCXPRT *transp; + socklen_t salen; + int ok; + struct sockaddr_storage sa; + + if (argc == 2 && !strcmp(argv[1], "-n")) + nodaemon = 1; + if (argc != 1 && !nodaemon) + usage(); + + if (geteuid() == 0) { + struct passwd *pep = getpwnam("nobody"); + if (pep) + setuid(pep->pw_uid); + else + setuid(getuid()); + } + + /* + * See if inetd started us + */ + salen = sizeof(sa); + if (getsockname(0, (struct sockaddr *)&sa, &salen) < 0) { + from_inetd = 0; + } + + if (!from_inetd) { + if (!nodaemon) + possess(); + + (void)rpcb_unset(WALLPROG, WALLVERS, NULL); + } + + (void)signal(SIGCHLD, killkids); + + openlog("rpc.rwalld", LOG_CONS|LOG_PID, LOG_DAEMON); + + /* create and register the service */ + if (from_inetd) { + transp = svc_tli_create(0, NULL, NULL, 0, 0); + if (transp == NULL) { + syslog(LOG_ERR, "couldn't create udp service."); + exit(1); + } + ok = svc_reg(transp, WALLPROG, WALLVERS, + wallprog_1, NULL); + } else + ok = svc_create(wallprog_1, + WALLPROG, WALLVERS, "udp"); + if (!ok) { + syslog(LOG_ERR, "unable to register (WALLPROG, WALLVERS, %s)", (!from_inetd)?"udp":"(inetd)"); + exit(1); + } + svc_run(); + syslog(LOG_ERR, "svc_run returned"); + exit(1); +} + +static void +usage(void) +{ + fprintf(stderr, "usage: rpc.rwalld [-n]\n"); + exit(1); +} + +void +possess(void) +{ + daemon(0, 0); +} + +void +killkids(int sig __unused) +{ + while(wait4(-1, NULL, WNOHANG, NULL) > 0) + ; +} + +void * +wallproc_wall_1_svc(wrapstring *s, struct svc_req *rqstp __unused) +{ + static void *dummy = NULL; + + /* fork, popen wall with special option, and send the message */ + if (fork() == 0) { + FILE *pfp; + + pfp = popen(WALL_CMD, "w"); + if (pfp != NULL) { + fprintf(pfp, "\007\007%s", *s); + pclose(pfp); + exit(0); + } + } + return(&dummy); +} + +void +wallprog_1(struct svc_req *rqstp, SVCXPRT *transp) +{ + union { + char *wallproc_wall_1_arg; + } argument; + void *result; + xdrproc_t xdr_argument, xdr_result; + typedef void *(svc_cb)(void *arg, struct svc_req *rqstp); + svc_cb *local; + + switch (rqstp->rq_proc) { + case NULLPROC: + (void)svc_sendreply(transp, (xdrproc_t)xdr_void, NULL); + goto leave; + + case WALLPROC_WALL: + xdr_argument = (xdrproc_t)xdr_wrapstring; + xdr_result = (xdrproc_t)xdr_void; + local = (svc_cb *)wallproc_wall_1_svc; + break; + + default: + svcerr_noproc(transp); + goto leave; + } + bzero(&argument, sizeof(argument)); + if (!svc_getargs(transp, xdr_argument, &argument)) { + svcerr_decode(transp); + goto leave; + } + result = (*local)(&argument, rqstp); + if (result != NULL && + !svc_sendreply(transp, xdr_result, result)) { + svcerr_systemerr(transp); + } + if (!svc_freeargs(transp, xdr_argument, &argument)) { + syslog(LOG_ERR, "unable to free arguments"); + exit(1); + } +leave: + if (from_inetd) + exit(0); +} |