freebsd-skq/libexec/rbootd/rbootd.c
pfg 872b698bd4 General further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:49:47 +00:00

452 lines
10 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1988, 1992 The University of Utah and the Center
* for Software Science (CSS).
* Copyright (c) 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Center for Software Science of the University of Utah Computer
* Science Department. CSS requests users of this software to return
* to css-dist@cs.utah.edu any improvements that they make and grant
* CSS redistribution rights.
*
* 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. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
*
* from: @(#)rbootd.c 8.1 (Berkeley) 6/4/93
*
* From: Utah Hdr: rbootd.c 3.1 92/07/06
* Author: Jeff Forys, University of Utah CSS
*/
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1992, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
#if 0
static const char sccsid[] = "@(#)rbootd.c 8.1 (Berkeley) 6/4/93";
#endif
#endif /* not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/time.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#include "defs.h"
static void usage(void);
int
main(int argc, char *argv[])
{
int c, fd, omask, maxfds;
fd_set rset;
/*
* Close any open file descriptors.
* Temporarily leave stdin & stdout open for `-d',
* and stderr open for any pre-syslog error messages.
*/
{
int i, nfds = getdtablesize();
for (i = 0; i < nfds; i++)
if (i != fileno(stdin) && i != fileno(stdout) &&
i != fileno(stderr))
(void) close(i);
}
/*
* Parse any arguments.
*/
while ((c = getopt(argc, argv, "adi:")) != -1)
switch(c) {
case 'a':
BootAny++;
break;
case 'd':
DebugFlg++;
break;
case 'i':
IntfName = optarg;
break;
default:
usage();
}
for (; optind < argc; optind++) {
if (ConfigFile == NULL)
ConfigFile = argv[optind];
else {
warnx("too many config files (`%s' ignored)",
argv[optind]);
}
}
if (ConfigFile == NULL) /* use default config file */
ConfigFile = DfltConfig;
if (DebugFlg) {
DbgFp = stdout; /* output to stdout */
(void) signal(SIGUSR1, SIG_IGN); /* dont muck w/DbgFp */
(void) signal(SIGUSR2, SIG_IGN);
(void) fclose(stderr); /* finished with it */
} else {
if (daemon(0, 0))
err(1, "can't detach from terminal");
(void) signal(SIGUSR1, DebugOn);
(void) signal(SIGUSR2, DebugOff);
}
openlog("rbootd", LOG_PID, LOG_DAEMON);
/*
* If no interface was specified, get one now.
*
* This is convoluted because we want to get the default interface
* name for the syslog("restarted") message. If BpfGetIntfName()
* runs into an error, it will return a syslog-able error message
* (in `errmsg') which will be displayed here.
*/
if (IntfName == NULL) {
char *errmsg;
if ((IntfName = BpfGetIntfName(&errmsg)) == NULL) {
/* Backslash to avoid trigraph '??)'. */
syslog(LOG_NOTICE, "restarted (?\?)");
/* BpfGetIntfName() returns safe names, using %m */
syslog(LOG_ERR, "%s", errmsg);
Exit(0);
}
}
syslog(LOG_NOTICE, "restarted (%s)", IntfName);
(void) signal(SIGHUP, ReConfig);
(void) signal(SIGINT, Exit);
(void) signal(SIGTERM, Exit);
/*
* Grab our host name and pid.
*/
if (gethostname(MyHost, MAXHOSTNAMELEN - 1) < 0) {
syslog(LOG_ERR, "gethostname: %m");
Exit(0);
}
MyHost[MAXHOSTNAMELEN - 1] = '\0';
MyPid = getpid();
/*
* Write proc's pid to a file.
*/
{
FILE *fp;
if ((fp = fopen(PidFile, "w")) != NULL) {
(void) fprintf(fp, "%d\n", (int) MyPid);
(void) fclose(fp);
} else {
syslog(LOG_WARNING, "fopen: failed (%s)", PidFile);
}
}
/*
* All boot files are relative to the boot directory, we might
* as well chdir() there to make life easier.
*/
if (chdir(BootDir) < 0) {
syslog(LOG_ERR, "chdir: %m (%s)", BootDir);
Exit(0);
}
/*
* Initial configuration.
*/
omask = sigblock(sigmask(SIGHUP)); /* prevent reconfig's */
if (GetBootFiles() == 0) /* get list of boot files */
Exit(0);
if (ParseConfig() == 0) /* parse config file */
Exit(0);
/*
* Open and initialize a BPF device for the appropriate interface.
* If an error is encountered, a message is displayed and Exit()
* is called.
*/
fd = BpfOpen();
(void) sigsetmask(omask); /* allow reconfig's */
/*
* Main loop: receive a packet, determine where it came from,
* and if we service this host, call routine to handle request.
*/
maxfds = fd + 1;
FD_ZERO(&rset);
FD_SET(fd, &rset);
for (;;) {
struct timeval timeout;
fd_set r;
int nsel;
r = rset;
if (RmpConns == NULL) { /* timeout isn't necessary */
nsel = select(maxfds, &r, NULL, NULL, NULL);
} else {
timeout.tv_sec = RMP_TIMEOUT;
timeout.tv_usec = 0;
nsel = select(maxfds, &r, NULL, NULL, &timeout);
}
if (nsel < 0) {
if (errno == EINTR)
continue;
syslog(LOG_ERR, "select: %m");
Exit(0);
} else if (nsel == 0) { /* timeout */
DoTimeout(); /* clear stale conns */
continue;
}
if (FD_ISSET(fd, &r)) {
RMPCONN rconn;
CLIENT *client, *FindClient();
int doread = 1;
while (BpfRead(&rconn, doread)) {
doread = 0;
if (DbgFp != NULL) /* display packet */
DispPkt(&rconn,DIR_RCVD);
omask = sigblock(sigmask(SIGHUP));
/*
* If we do not restrict service, set the
* client to NULL (ProcessPacket() handles
* this). Otherwise, check that we can
* service this host; if not, log a message
* and ignore the packet.
*/
if (BootAny) {
client = NULL;
} else if ((client=FindClient(&rconn))==NULL) {
syslog(LOG_INFO,
"%s: boot packet ignored",
EnetStr(&rconn));
(void) sigsetmask(omask);
continue;
}
ProcessPacket(&rconn,client);
(void) sigsetmask(omask);
}
}
}
}
static void
usage(void)
{
fprintf(stderr, "usage: rbootd [-ad] [-i interface] [config_file]\n");
exit (1);
}
/*
** DoTimeout -- Free any connections that have timed out.
**
** Parameters:
** None.
**
** Returns:
** Nothing.
**
** Side Effects:
** - Timed out connections in `RmpConns' will be freed.
*/
void
DoTimeout(void)
{
RMPCONN *rtmp;
time_t now;
/*
* For each active connection, if RMP_TIMEOUT seconds have passed
* since the last packet was sent, delete the connection.
*/
now = time(NULL);
for (rtmp = RmpConns; rtmp != NULL; rtmp = rtmp->next)
if ((rtmp->tstamp.tv_sec + RMP_TIMEOUT) < now) {
syslog(LOG_WARNING, "%s: connection timed out (%u)",
EnetStr(rtmp), rtmp->rmp.r_type);
RemoveConn(rtmp);
}
}
/*
** FindClient -- Find client associated with a packet.
**
** Parameters:
** rconn - the new packet.
**
** Returns:
** Pointer to client info if found, NULL otherwise.
**
** Side Effects:
** None.
**
** Warnings:
** - This routine must be called with SIGHUP blocked since
** a reconfigure can invalidate the information returned.
*/
CLIENT *
FindClient(RMPCONN *rconn)
{
CLIENT *ctmp;
for (ctmp = Clients; ctmp != NULL; ctmp = ctmp->next)
if (bcmp((char *)&rconn->rmp.hp_hdr.saddr[0],
(char *)&ctmp->addr[0], RMP_ADDRLEN) == 0)
break;
return(ctmp);
}
/*
** Exit -- Log an error message and exit.
**
** Parameters:
** sig - caught signal (or zero if not dying on a signal).
**
** Returns:
** Does not return.
**
** Side Effects:
** - This process ceases to exist.
*/
void
Exit(int sig)
{
if (sig > 0)
syslog(LOG_ERR, "going down on signal %d", sig);
else
syslog(LOG_ERR, "going down with fatal error");
BpfClose();
exit(1);
}
/*
** ReConfig -- Get new list of boot files and reread config files.
**
** Parameters:
** None.
**
** Returns:
** Nothing.
**
** Side Effects:
** - All active connections are dropped.
** - List of boot-able files is changed.
** - List of clients is changed.
**
** Warnings:
** - This routine must be called with SIGHUP blocked.
*/
void
ReConfig(int signo __unused)
{
syslog(LOG_NOTICE, "reconfiguring boot server");
FreeConns();
if (GetBootFiles() == 0)
Exit(0);
if (ParseConfig() == 0)
Exit(0);
}
/*
** DebugOff -- Turn off debugging.
**
** Parameters:
** None.
**
** Returns:
** Nothing.
**
** Side Effects:
** - Debug file is closed.
*/
void
DebugOff(int signo __unused)
{
if (DbgFp != NULL)
(void) fclose(DbgFp);
DbgFp = NULL;
}
/*
** DebugOn -- Turn on debugging.
**
** Parameters:
** None.
**
** Returns:
** Nothing.
**
** Side Effects:
** - Debug file is opened/truncated if not already opened,
** otherwise do nothing.
*/
void
DebugOn(int signo __unused)
{
if (DbgFp == NULL) {
if ((DbgFp = fopen(DbgFile, "w")) == NULL)
syslog(LOG_ERR, "can't open debug file (%s)", DbgFile);
}
}