/* $OpenBSD: rbootd.c,v 1.32 2019/06/28 13:32:50 deraadt Exp $ */ /* $NetBSD: rbootd.c,v 1.5 1995/10/06 05:12:17 thorpej Exp $ */ /* * 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 */ #include <sys/time.h> #include <err.h> #include <errno.h> #include <signal.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <syslog.h> #include <unistd.h> #include <limits.h> #include <pwd.h> #include <poll.h> #include "defs.h" extern char *__progname; /* from crt0.o */ volatile sig_atomic_t dodebugoff; volatile sig_atomic_t dodebugon; volatile sig_atomic_t doreconfig; void DebugOff(int); void DebugOn(int); void ReConfig(int); void Exit(int); void DoDebugOff(void); void DoDebugOn(void); void DoReConfig(void); void DoTimeout(void); CLIENT *FindClient(RMPCONN *); int main(int argc, char *argv[]) { int c, fd; struct passwd *pw; struct pollfd pfd[1]; closefrom(STDERR_FILENO + 1); if ((pw = getpwnam("_rbootd")) == NULL) err(1, "getpwnam"); while ((c = getopt(argc, argv, "adi:")) != -1) switch (c) { case 'a': BootAny++; break; case 'd': DebugFlg++; break; case 'i': IntfName = optarg; break; } 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); } /* * 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) { /* BpfGetIntfName() returns safe names, using %m */ syslog(LOG_ERR, "%s", errmsg); DoExit(); } } openlog(__progname, LOG_PID, LOG_DAEMON); fd = BpfOpen(); syslog(LOG_NOTICE, "restarted (%s)", IntfName); (void) signal(SIGHUP, ReConfig); (void) signal(SIGINT, Exit); (void) signal(SIGTERM, Exit); gethostname(MyHost, HOST_NAME_MAX+1); /* * All boot files are relative to the boot directory, we might * as well chdir() there to make life easier. */ if (chdir(BootDir) == -1) { syslog(LOG_ERR, "chdir: %m (%s)", BootDir); DoExit(); } /* * Initial configuration. */ if (GetBootFiles() == 0) /* get list of boot files */ DoExit(); if (ParseConfig() == 0) /* parse config file */ DoExit(); if (chroot(BootDir) == -1) { syslog(LOG_CRIT, "chroot %s: %m", BootDir); exit(1); } if (chdir("/") == -1) { syslog(LOG_CRIT, "chdir(\"/\"): %m"); exit(1); } if (setgroups(1, &pw->pw_gid) || setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) || setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid)) { syslog(LOG_CRIT, "can't drop privileges: %m"); exit(1); } endpwent(); /* * Main loop: receive a packet, determine where it came from, * and if we service this host, call routine to handle request. */ pfd[0].fd = fd; pfd[0].events = POLLIN; for (;;) { int nsel; /* * Check pending actions */ if (dodebugoff) { DoDebugOff(); dodebugoff = 0; } if (dodebugon) { DoDebugOn(); dodebugon = 0; } if (doreconfig) { DoReConfig(); doreconfig = 0; } nsel = poll(pfd, 1, RmpConns ? RMP_TIMEOUT * 100 : -1); if (nsel == -1) { if (errno == EINTR) continue; syslog(LOG_ERR, "poll: %m"); DoExit(); } else if (nsel == 0) { /* timeout */ DoTimeout(); /* clear stale conns */ continue; } if (pfd[0].revents & POLLIN) { RMPCONN rconn; CLIENT *client; int doread = 1; while (BpfRead(&rconn, doread)) { doread = 0; if (DbgFp != NULL) /* display packet */ DispPkt(&rconn,DIR_RCVD); /* * 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)); continue; } ProcessPacket(&rconn,client); } } } } /* ** 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; struct timeval now; (void) gettimeofday(&now, NULL); /* * For each active connection, if RMP_TIMEOUT seconds have passed * since the last packet was sent, delete the connection. */ for (rtmp = RmpConns; rtmp != NULL; rtmp = rtmp->next) if ((rtmp->tstamp.tv_sec + RMP_TIMEOUT) < now.tv_sec) { 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) { struct syslog_data sdata = SYSLOG_DATA_INIT; syslog_r(LOG_ERR, &sdata, "going down on signal %d", sig); _exit(1); } void DoExit(void) { syslog(LOG_ERR, "going down on fatal error"); 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 bootable files is changed. ** - List of clients is changed. ** ** Warnings: ** - This routine must be called with SIGHUP blocked. */ void ReConfig(int signo) { doreconfig = 1; } void DoReConfig(void) { syslog(LOG_NOTICE, "reconfiguring boot server"); FreeConns(); if (GetBootFiles() == 0) DoExit(); if (ParseConfig() == 0) DoExit(); } /* ** DebugOff -- Turn off debugging. ** ** Parameters: ** None. ** ** Returns: ** Nothing. ** ** Side Effects: ** - Debug file is closed. */ void DebugOff(int signo) { dodebugoff = 1; } void DoDebugOff(void) { 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) { dodebugon = 1; } void DoDebugOn(void) { if (DbgFp == NULL) { if ((DbgFp = fopen(DbgFile, "w")) == NULL) syslog(LOG_ERR, "can't open debug file (%s)", DbgFile); } }
