diff options
Diffstat (limited to 'libexec/bootpd/bootpd.c')
| -rw-r--r-- | libexec/bootpd/bootpd.c | 1396 |
1 files changed, 1396 insertions, 0 deletions
diff --git a/libexec/bootpd/bootpd.c b/libexec/bootpd/bootpd.c new file mode 100644 index 000000000000..f73671dab074 --- /dev/null +++ b/libexec/bootpd/bootpd.c @@ -0,0 +1,1396 @@ +/************************************************************************ + Copyright 1988, 1991 by Carnegie Mellon University + + All Rights Reserved + +Permission to use, copy, modify, and distribute this software and its +documentation for any purpose and without fee is hereby granted, provided +that the above copyright notice appear in all copies and that both that +copyright notice and this permission notice appear in supporting +documentation, and that the name of Carnegie Mellon University not be used +in advertising or publicity pertaining to distribution of the software +without specific, written prior permission. + +CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS +SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. +IN NO EVENT SHALL CMU BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL +DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR +PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS +ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS +SOFTWARE. + +************************************************************************/ + +/* + * BOOTP (bootstrap protocol) server daemon. + * + * Answers BOOTP request packets from booting client machines. + * See [SRI-NIC]<RFC>RFC951.TXT for a description of the protocol. + * See [SRI-NIC]<RFC>RFC1048.TXT for vendor-information extensions. + * See RFC 1395 for option tags 14-17. + * See accompanying man page -- bootpd.8 + * + * HISTORY + * See ./Changes + * + * BUGS + * See ./ToDo + */ + +#include <sys/types.h> +#include <sys/param.h> +#include <sys/socket.h> +#include <sys/ioctl.h> +#include <sys/file.h> +#include <sys/time.h> +#include <sys/stat.h> +#include <sys/utsname.h> + +#include <net/if.h> +#include <netinet/in.h> +#include <arpa/inet.h> /* inet_ntoa */ + +#ifndef NO_UNISTD +#include <unistd.h> +#endif + +#include <stdlib.h> +#include <signal.h> +#include <stdio.h> +#include <string.h> +#include <errno.h> +#include <ctype.h> +#include <netdb.h> +#include <paths.h> +#include <syslog.h> +#include <assert.h> +#include <inttypes.h> + +#ifdef NO_SETSID +# include <fcntl.h> /* for O_RDONLY, etc */ +#endif + +#include "bootp.h" +#include "hash.h" +#include "hwaddr.h" +#include "bootpd.h" +#include "dovend.h" +#include "getif.h" +#include "readfile.h" +#include "report.h" +#include "tzone.h" +#include "patchlevel.h" + +#ifndef CONFIG_FILE +#define CONFIG_FILE "/etc/bootptab" +#endif +#ifndef DUMPTAB_FILE +#define DUMPTAB_FILE "/tmp/bootpd.dump" +#endif + + + +/* + * Externals, forward declarations, and global variables + */ + +extern void dumptab(char *); + +PRIVATE void catcher(int); +PRIVATE int chk_access(char *, int32 *); +#ifdef VEND_CMU +PRIVATE void dovend_cmu(struct bootp *, struct host *); +#endif +PRIVATE void dovend_rfc1048(struct bootp *, struct host *, int32); +PRIVATE void handle_reply(void); +PRIVATE void handle_request(void); +PRIVATE void sendreply(int forward, int32 dest_override); +PRIVATE void usage(void); + +/* + * IP port numbers for client and server obtained from /etc/services + */ + +u_short bootps_port, bootpc_port; + + +/* + * Internet socket and interface config structures + */ + +struct sockaddr_in bind_addr; /* Listening */ +struct sockaddr_in recv_addr; /* Packet source */ +struct sockaddr_in send_addr; /* destination */ + + +/* + * option defaults + */ +int debug = 0; /* Debugging flag (level) */ +struct timeval actualtimeout = +{ /* fifteen minutes */ + 15 * 60L, /* tv_sec */ + 0 /* tv_usec */ +}; +int arpmod = TRUE; /* modify the ARP table */ + +/* + * General + */ + +int s; /* Socket file descriptor */ +char *pktbuf; /* Receive packet buffer */ +int pktlen; +char *progname; +char *chdir_path; +struct in_addr my_ip_addr; + +static const char *hostname; +static char default_hostname[MAXHOSTNAMELEN]; + +/* Flags set by signal catcher. */ +PRIVATE int do_readtab = 0; +PRIVATE int do_dumptab = 0; + +/* + * Globals below are associated with the bootp database file (bootptab). + */ + +char *bootptab = CONFIG_FILE; +char *bootpd_dump = DUMPTAB_FILE; + + + +/* + * Initialization such as command-line processing is done and then the + * main server loop is started. + */ + +int +main(int argc, char **argv) +{ + struct timeval *timeout; + struct bootp *bp; + struct servent *servp; + struct hostent *hep; + char *stmp; + socklen_t ba_len, ra_len; + int n; + int nfound; + fd_set readfds; + int standalone; +#ifdef SA_NOCLDSTOP /* Have POSIX sigaction(2). */ + struct sigaction sa; +#endif + + progname = strrchr(argv[0], '/'); + if (progname) progname++; + else progname = argv[0]; + + /* + * Initialize logging. + */ + report_init(0); /* uses progname */ + + /* + * Log startup + */ + report(LOG_INFO, "version %s.%d", VERSION, PATCHLEVEL); + + /* Debugging for compilers with struct padding. */ + assert(sizeof(struct bootp) == BP_MINPKTSZ); + + /* Get space for receiving packets and composing replies. */ + pktbuf = malloc(MAX_MSG_SIZE); + if (!pktbuf) { + report(LOG_ERR, "malloc failed"); + exit(1); + } + bp = (struct bootp *) pktbuf; + + /* + * Check to see if a socket was passed to us from inetd. + * + * Use getsockname() to determine if descriptor 0 is indeed a socket + * (and thus we are probably a child of inetd) or if it is instead + * something else and we are running standalone. + */ + s = 0; + ba_len = sizeof(bind_addr); + bzero((char *) &bind_addr, ba_len); + errno = 0; + standalone = TRUE; + if (getsockname(s, (struct sockaddr *) &bind_addr, &ba_len) == 0) { + /* + * Descriptor 0 is a socket. Assume we are a child of inetd. + */ + if (bind_addr.sin_family == AF_INET) { + standalone = FALSE; + bootps_port = ntohs(bind_addr.sin_port); + } else { + /* Some other type of socket? */ + report(LOG_ERR, "getsockname: not an INET socket"); + } + } + + /* + * Set defaults that might be changed by option switches. + */ + stmp = NULL; + timeout = &actualtimeout; + + if (gethostname(default_hostname, sizeof(default_hostname) - 1) < 0) { + report(LOG_ERR, "bootpd: can't get hostname\n"); + exit(1); + } + default_hostname[sizeof(default_hostname) - 1] = '\0'; + hostname = default_hostname; + + /* + * Read switches. + */ + for (argc--, argv++; argc > 0; argc--, argv++) { + if (argv[0][0] != '-') + break; + switch (argv[0][1]) { + + case 'a': /* don't modify the ARP table */ + arpmod = FALSE; + break; + case 'c': /* chdir_path */ + if (argv[0][2]) { + stmp = &(argv[0][2]); + } else { + argc--; + argv++; + stmp = argv[0]; + } + if (!stmp || (stmp[0] != '/')) { + report(LOG_ERR, + "bootpd: invalid chdir specification\n"); + break; + } + chdir_path = stmp; + break; + + case 'd': /* debug level */ + if (argv[0][2]) { + stmp = &(argv[0][2]); + } else if (argv[1] && argv[1][0] == '-') { + /* + * Backwards-compatible behavior: + * no parameter, so just increment the debug flag. + */ + debug++; + break; + } else { + argc--; + argv++; + stmp = argv[0]; + } + if (!stmp || (sscanf(stmp, "%d", &n) != 1) || (n < 0)) { + report(LOG_ERR, + "%s: invalid debug level\n", progname); + break; + } + debug = n; + break; + + case 'h': /* override hostname */ + if (argv[0][2]) { + stmp = &(argv[0][2]); + } else { + argc--; + argv++; + stmp = argv[0]; + } + if (!stmp) { + report(LOG_ERR, + "bootpd: missing hostname\n"); + break; + } + hostname = stmp; + break; + + case 'i': /* inetd mode */ + standalone = FALSE; + break; + + case 's': /* standalone mode */ + standalone = TRUE; + break; + + case 't': /* timeout */ + if (argv[0][2]) { + stmp = &(argv[0][2]); + } else { + argc--; + argv++; + stmp = argv[0]; + } + if (!stmp || (sscanf(stmp, "%d", &n) != 1) || (n < 0)) { + report(LOG_ERR, + "%s: invalid timeout specification\n", progname); + break; + } + actualtimeout.tv_sec = (int32) (60 * n); + /* + * If the actual timeout is zero, pass a NULL pointer + * to select so it blocks indefinitely, otherwise, + * point to the actual timeout value. + */ + timeout = (n > 0) ? &actualtimeout : NULL; + break; + + default: + report(LOG_ERR, "%s: unknown switch: -%c\n", + progname, argv[0][1]); + usage(); + break; + + } /* switch */ + } /* for args */ + + /* + * Override default file names if specified on the command line. + */ + if (argc > 0) + bootptab = argv[0]; + + if (argc > 1) + bootpd_dump = argv[1]; + + /* + * Get my hostname and IP address. + */ + + hep = gethostbyname(hostname); + if (!hep) { + report(LOG_ERR, "Can not get my IP address\n"); + exit(1); + } + bcopy(hep->h_addr, (char *)&my_ip_addr, sizeof(my_ip_addr)); + + if (standalone) { + /* + * Go into background and disassociate from controlling terminal. + */ + if (debug < 3) { + if (fork()) + exit(0); +#ifdef NO_SETSID + setpgrp(0,0); +#ifdef TIOCNOTTY + n = open(_PATH_TTY, O_RDWR); + if (n >= 0) { + ioctl(n, TIOCNOTTY, (char *) 0); + (void) close(n); + } +#endif /* TIOCNOTTY */ +#else /* SETSID */ + if (setsid() < 0) + perror("setsid"); +#endif /* SETSID */ + } /* if debug < 3 */ + + /* + * Nuke any timeout value + */ + timeout = NULL; + + } /* if standalone (1st) */ + + /* Set the cwd (i.e. to /tftpboot) */ + if (chdir_path) { + if (chdir(chdir_path) < 0) + report(LOG_ERR, "%s: chdir failed", chdir_path); + } + + /* Get the timezone. */ + tzone_init(); + + /* Allocate hash tables. */ + rdtab_init(); + + /* + * Read the bootptab file. + */ + readtab(1); /* force read */ + + if (standalone) { + + /* + * Create a socket. + */ + if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { + report(LOG_ERR, "socket: %s", get_network_errmsg()); + exit(1); + } + + /* + * Get server's listening port number + */ + servp = getservbyname("bootps", "udp"); + if (servp) { + bootps_port = ntohs((u_short) servp->s_port); + } else { + bootps_port = (u_short) IPPORT_BOOTPS; + report(LOG_ERR, + "bootps/udp: unknown service -- using port %d", + bootps_port); + } + + /* + * Bind socket to BOOTPS port. + */ + bind_addr.sin_family = AF_INET; + bind_addr.sin_addr.s_addr = INADDR_ANY; + bind_addr.sin_port = htons(bootps_port); + if (bind(s, (struct sockaddr *) &bind_addr, + sizeof(bind_addr)) < 0) + { + report(LOG_ERR, "bind: %s", get_network_errmsg()); + exit(1); + } + } /* if standalone (2nd)*/ + + /* + * Get destination port number so we can reply to client + */ + servp = getservbyname("bootpc", "udp"); + if (servp) { + bootpc_port = ntohs(servp->s_port); + } else { + report(LOG_ERR, + "bootpc/udp: unknown service -- using port %d", + IPPORT_BOOTPC); + bootpc_port = (u_short) IPPORT_BOOTPC; + } + + /* + * Set up signals to read or dump the table. + */ +#ifdef SA_NOCLDSTOP /* Have POSIX sigaction(2). */ + sa.sa_handler = catcher; + sigemptyset(&sa.sa_mask); + sa.sa_flags = 0; + if (sigaction(SIGHUP, &sa, NULL) < 0) { + report(LOG_ERR, "sigaction: %s", get_errmsg()); + exit(1); + } + if (sigaction(SIGUSR1, &sa, NULL) < 0) { + report(LOG_ERR, "sigaction: %s", get_errmsg()); + exit(1); + } +#else /* SA_NOCLDSTOP */ + /* Old-fashioned UNIX signals */ + if ((int) signal(SIGHUP, catcher) < 0) { + report(LOG_ERR, "signal: %s", get_errmsg()); + exit(1); + } + if ((int) signal(SIGUSR1, catcher) < 0) { + report(LOG_ERR, "signal: %s", get_errmsg()); + exit(1); + } +#endif /* SA_NOCLDSTOP */ + + /* + * Process incoming requests. + */ + FD_ZERO(&readfds); + for (;;) { + struct timeval tv; + + FD_SET(s, &readfds); + if (timeout) + tv = *timeout; + + nfound = select(s + 1, &readfds, NULL, NULL, + (timeout) ? &tv : NULL); + if (nfound < 0) { + if (errno != EINTR) { + report(LOG_ERR, "select: %s", get_errmsg()); + } + /* + * Call readtab() or dumptab() here to avoid the + * dangers of doing I/O from a signal handler. + */ + if (do_readtab) { + do_readtab = 0; + readtab(1); /* force read */ + } + if (do_dumptab) { + do_dumptab = 0; + dumptab(bootpd_dump); + } + continue; + } + if (!FD_ISSET(s, &readfds)) { + if (debug > 1) + report(LOG_INFO, "exiting after %jd minutes of inactivity", + (intmax_t)actualtimeout.tv_sec / 60); + exit(0); + } + ra_len = sizeof(recv_addr); + n = recvfrom(s, pktbuf, MAX_MSG_SIZE, 0, + (struct sockaddr *) &recv_addr, &ra_len); + if (n <= 0) { + continue; + } + if (debug > 1) { + report(LOG_INFO, "recvd pkt from IP addr %s", + inet_ntoa(recv_addr.sin_addr)); + } + if (n < sizeof(struct bootp)) { + if (debug) { + report(LOG_NOTICE, "received short packet"); + } + continue; + } + pktlen = n; + + readtab(0); /* maybe re-read bootptab */ + + switch (bp->bp_op) { + case BOOTREQUEST: + handle_request(); + break; + case BOOTREPLY: + handle_reply(); + break; + } + } + return 0; +} + + + + +/* + * Print "usage" message and exit + */ + +PRIVATE void +usage() +{ + fprintf(stderr, + "usage: bootpd [-a] [-i | -s] [-c chdir-path] [-d level] [-h hostname]\n" + " [-t timeout] [bootptab [dumpfile]]\n"); + fprintf(stderr, " -a\tdon't modify ARP table\n"); + fprintf(stderr, " -c n\tset current directory\n"); + fprintf(stderr, " -d n\tset debug level\n"); + fprintf(stderr, " -h n\tset the hostname to listen on\n"); + fprintf(stderr, " -i\tforce inetd mode (run as child of inetd)\n"); + fprintf(stderr, " -s\tforce standalone mode (run without inetd)\n"); + fprintf(stderr, " -t n\tset inetd exit timeout to n minutes\n"); + exit(1); +} + +/* Signal catchers */ +PRIVATE void +catcher(int sig) +{ + if (sig == SIGHUP) + do_readtab = 1; + if (sig == SIGUSR1) + do_dumptab = 1; +#if !defined(SA_NOCLDSTOP) && defined(SYSV) + /* For older "System V" derivatives with no sigaction(). */ + signal(sig, catcher); +#endif +} + + + +/* + * Process BOOTREQUEST packet. + * + * Note: This version of the bootpd.c server never forwards + * a request to another server. That is the job of a gateway + * program such as the "bootpgw" program included here. + * + * (Also this version does not interpret the hostname field of + * the request packet; it COULD do a name->address lookup and + * forward the request there.) + */ +PRIVATE void +handle_request(void) +{ + struct bootp *bp = (struct bootp *) pktbuf; + struct host *hp = NULL; + struct host dummyhost; + int32 bootsize = 0; + unsigned hlen, hashcode; + int32 dest; + char realpath[1024]; + char *clntpath; + char *homedir, *bootfile; + int n; + + if (bp->bp_htype >= hwinfocnt) { + report(LOG_NOTICE, "bad hw addr type %u", bp->bp_htype); + return; + } + bp->bp_file[sizeof(bp->bp_file)-1] = '\0'; + + /* XXX - SLIP init: Set bp_ciaddr = recv_addr here? */ + + /* + * If the servername field is set, compare it against us. + * If we're not being addressed, ignore this request. + * If the server name field is null, throw in our name. + */ + if (strlen(bp->bp_sname)) { + if (strcmp(bp->bp_sname, hostname)) { + if (debug) + report(LOG_INFO, "\ +ignoring request for server %s from client at %s address %s", + bp->bp_sname, netname(bp->bp_htype), + haddrtoa(bp->bp_chaddr, bp->bp_hlen)); + /* XXX - Is it correct to ignore such a request? -gwr */ + return; + } + } else { + strcpy(bp->bp_sname, hostname); + } + + /* Convert the request into a reply. */ + bp->bp_op = BOOTREPLY; + if (bp->bp_ciaddr.s_addr == 0) { + /* + * client doesn't know his IP address, + * search by hardware address. + */ + if (debug > 1) { + report(LOG_INFO, "request from %s address %s", + netname(bp->bp_htype), + haddrtoa(bp->bp_chaddr, bp->bp_hlen)); + } + hlen = haddrlength(bp->bp_htype); + if (hlen != bp->bp_hlen) { + report(LOG_NOTICE, "bad addr len from %s address %s", + netname(bp->bp_htype), + haddrtoa(bp->bp_chaddr, hlen)); + } + dummyhost.htype = bp->bp_htype; + bcopy(bp->bp_chaddr, dummyhost.haddr, hlen); + hashcode = hash_HashFunction(bp->bp_chaddr, hlen); + hp = (struct host *) hash_Lookup(hwhashtable, hashcode, hwlookcmp, + &dummyhost); + if (hp == NULL && + bp->bp_htype == HTYPE_IEEE802) + { + /* Try again with address in "canonical" form. */ + haddr_conv802(bp->bp_chaddr, dummyhost.haddr, hlen); + if (debug > 1) { + report(LOG_INFO, "\ +HW addr type is IEEE 802. convert to %s and check again\n", + haddrtoa(dummyhost.haddr, bp->bp_hlen)); + } + hashcode = hash_HashFunction(dummyhost.haddr, hlen); + hp = (struct host *) hash_Lookup(hwhashtable, hashcode, + hwlookcmp, &dummyhost); + } + if (hp == NULL) { + /* + * XXX - Add dynamic IP address assignment? + */ + if (debug) + report(LOG_NOTICE, "unknown client %s address %s", + netname(bp->bp_htype), + haddrtoa(bp->bp_chaddr, bp->bp_hlen)); + return; /* not found */ + } + (bp->bp_yiaddr).s_addr = hp->iaddr.s_addr; + + } else { + + /* + * search by IP address. + */ + if (debug > 1) { + report(LOG_INFO, "request from IP addr %s", + inet_ntoa(bp->bp_ciaddr)); + } + dummyhost.iaddr.s_addr = bp->bp_ciaddr.s_addr; + hashcode = hash_HashFunction((u_char *) &(bp->bp_ciaddr.s_addr), 4); + hp = (struct host *) hash_Lookup(iphashtable, hashcode, iplookcmp, + &dummyhost); + if (hp == NULL) { + if (debug) { + report(LOG_NOTICE, "IP address not found: %s", + inet_ntoa(bp->bp_ciaddr)); + } + return; + } + } + + if (debug) { + report(LOG_INFO, "found %s (%s)", inet_ntoa(hp->iaddr), + hp->hostname->string); + } + + /* + * If there is a response delay threshold, ignore requests + * with a timestamp lower than the threshold. + */ + if (hp->flags.min_wait) { + u_int32 t = (u_int32) ntohs(bp->bp_secs); + if (t < hp->min_wait) { + if (debug > 1) + report(LOG_INFO, + "ignoring request due to timestamp (%d < %d)", + t, hp->min_wait); + return; + } + } + +#ifdef YORK_EX_OPTION + /* + * The need for the "ex" tag arose out of the need to empty + * shared networked drives on diskless PCs. This solution is + * not very clean but it does work fairly well. + * Written by Edmund J. Sutcliffe <edmund@york.ac.uk> + * + * XXX - This could compromise security if a non-trusted user + * managed to write an entry in the bootptab with :ex=trojan: + * so I would leave this turned off unless you need it. -gwr + */ + /* Run a program, passing the client name as a parameter. */ + if (hp->flags.exec_file) { + char tst[100]; + /* XXX - Check string lengths? -gwr */ + strcpy (tst, hp->exec_file->string); + strcat (tst, " "); + strcat (tst, hp->hostname->string); + strcat (tst, " &"); + if (debug) + report(LOG_INFO, "executing %s", tst); + system(tst); /* Hope this finishes soon... */ + } +#endif /* YORK_EX_OPTION */ + + /* + * If a specific TFTP server address was specified in the bootptab file, + * fill it in, otherwise zero it. + * XXX - Rather than zero it, should it be the bootpd address? -gwr + */ + (bp->bp_siaddr).s_addr = (hp->flags.bootserver) ? + hp->bootserver.s_addr : 0L; + +#ifdef STANFORD_PROM_COMPAT + /* + * Stanford bootp PROMs (for a Sun?) have no way to leave + * the boot file name field blank (because the boot file + * name is automatically generated from some index). + * As a work-around, this little hack allows those PROMs to + * specify "sunboot14" with the same effect as a NULL name. + * (The user specifies boot device 14 or some such magic.) + */ + if (strcmp(bp->bp_file, "sunboot14") == 0) + bp->bp_file[0] = '\0'; /* treat it as unspecified */ +#endif + + /* + * Fill in the client's proper bootfile. + * + * If the client specifies an absolute path, try that file with a + * ".host" suffix and then without. If the file cannot be found, no + * reply is made at all. + * + * If the client specifies a null or relative file, use the following + * table to determine the appropriate action: + * + * Homedir Bootfile Client's file + * specified? specified? specification Action + * ------------------------------------------------------------------- + * No No Null Send null filename + * No No Relative Discard request + * No Yes Null Send if absolute else null + * No Yes Relative Discard request *XXX + * Yes No Null Send null filename + * Yes No Relative Lookup with ".host" + * Yes Yes Null Send home/boot or bootfile + * Yes Yes Relative Lookup with ".host" *XXX + * + */ + + /* + * XXX - I don't like the policy of ignoring a client when the + * boot file is not accessible. The TFTP server might not be + * running on the same machine as the BOOTP server, in which + * case checking accessibility of the boot file is pointless. + * + * Therefore, file accessibility is now demanded ONLY if you + * define CHECK_FILE_ACCESS in the Makefile options. -gwr + */ + + /* + * The "real" path is as seen by the BOOTP daemon on this + * machine, while the client path is relative to the TFTP + * daemon chroot directory (i.e. /tftpboot). + */ + if (hp->flags.tftpdir) { + snprintf(realpath, sizeof(realpath), "%s", hp->tftpdir->string); + clntpath = &realpath[strlen(realpath)]; + } else { + realpath[0] = '\0'; + clntpath = realpath; + } + + /* + * Determine client's requested homedir and bootfile. + */ + homedir = NULL; + bootfile = NULL; + if (bp->bp_file[0]) { + homedir = bp->bp_file; + bootfile = strrchr(homedir, '/'); + if (bootfile) { + if (homedir == bootfile) + homedir = NULL; + *bootfile++ = '\0'; + } else { + /* no "/" in the string */ + bootfile = homedir; + homedir = NULL; + } + if (debug > 2) { + report(LOG_INFO, "requested path=\"%s\" file=\"%s\"", + (homedir) ? homedir : "", + (bootfile) ? bootfile : ""); + } + } + + /* + * Specifications in bootptab override client requested values. + */ + if (hp->flags.homedir) + homedir = hp->homedir->string; + if (hp->flags.bootfile) + bootfile = hp->bootfile->string; + + /* + * Construct bootfile path. + */ + if (homedir) { + if (homedir[0] != '/') + strcat(clntpath, "/"); + strcat(clntpath, homedir); + homedir = NULL; + } + if (bootfile) { + if (bootfile[0] != '/') + strcat(clntpath, "/"); + strcat(clntpath, bootfile); + bootfile = NULL; + } + + /* + * First try to find the file with a ".host" suffix + */ + n = strlen(clntpath); + strcat(clntpath, "."); + strcat(clntpath, hp->hostname->string); + if (chk_access(realpath, &bootsize) < 0) { + clntpath[n] = 0; /* Try it without the suffix */ + if (chk_access(realpath, &bootsize) < 0) { + /* neither "file.host" nor "file" was found */ +#ifdef CHECK_FILE_ACCESS + + if (bp->bp_file[0]) { + /* + * Client wanted specific file + * and we didn't have it. + */ + report(LOG_NOTICE, + "requested file not found: \"%s\"", clntpath); + return; + } + /* + * Client didn't ask for a specific file and we couldn't + * access the default file, so just zero-out the bootfile + * field in the packet and continue processing the reply. + */ + bzero(bp->bp_file, sizeof(bp->bp_file)); + goto null_file_name; + +#else /* CHECK_FILE_ACCESS */ + + /* Complain only if boot file size was needed. */ + if (hp->flags.bootsize_auto) { + report(LOG_ERR, "can not determine size of file \"%s\"", + clntpath); + } + +#endif /* CHECK_FILE_ACCESS */ + } + } + strncpy(bp->bp_file, clntpath, BP_FILE_LEN); + if (debug > 2) + report(LOG_INFO, "bootfile=\"%s\"", clntpath); + +#ifdef CHECK_FILE_ACCESS +null_file_name: +#endif /* CHECK_FILE_ACCESS */ + + + /* + * Handle vendor options based on magic number. + */ + + if (debug > 1) { + report(LOG_INFO, "vendor magic field is %d.%d.%d.%d", + (int) ((bp->bp_vend)[0]), + (int) ((bp->bp_vend)[1]), + (int) ((bp->bp_vend)[2]), + (int) ((bp->bp_vend)[3])); + } + /* + * If this host isn't set for automatic vendor info then copy the + * specific cookie into the bootp packet, thus forcing a certain + * reply format. Only force reply format if user specified it. + */ + if (hp->flags.vm_cookie) { + /* Slam in the user specified magic number. */ + bcopy(hp->vm_cookie, bp->bp_vend, 4); + } + /* + * Figure out the format for the vendor-specific info. + * Note that bp->bp_vend may have been set above. + */ + if (!bcmp(bp->bp_vend, vm_rfc1048, 4)) { + /* RFC1048 conformant bootp client */ + dovend_rfc1048(bp, hp, bootsize); + if (debug > 1) { + report(LOG_INFO, "sending reply (with RFC1048 options)"); + } + } +#ifdef VEND_CMU + else if (!bcmp(bp->bp_vend, vm_cmu, 4)) { + dovend_cmu(bp, hp); + if (debug > 1) { + report(LOG_INFO, "sending reply (with CMU options)"); + } + } +#endif + else { + if (debug > 1) { + report(LOG_INFO, "sending reply (with no options)"); + } + } + + dest = (hp->flags.reply_addr) ? + hp->reply_addr.s_addr : 0L; + + /* not forwarded */ + sendreply(0, dest); +} + + +/* + * Process BOOTREPLY packet. + */ +PRIVATE void +handle_reply(void) +{ + if (debug) { + report(LOG_INFO, "processing boot reply"); + } + /* forwarded, no destination override */ + sendreply(1, 0); +} + + +/* + * Send a reply packet to the client. 'forward' flag is set if we are + * not the originator of this reply packet. + */ +PRIVATE void +sendreply(int forward, int32 dst_override) +{ + struct bootp *bp = (struct bootp *) pktbuf; + struct in_addr dst; + u_short port = bootpc_port; + unsigned char *ha; + int len, haf; + + /* + * XXX - Should honor bp_flags "broadcast" bit here. + * Temporary workaround: use the :ra=ADDR: option to + * set the reply address to the broadcast address. + */ + + /* + * If the destination address was specified explicitly + * (i.e. the broadcast address for HP compatibility) + * then send the response to that address. Otherwise, + * act in accordance with RFC951: + * If the client IP address is specified, use that + * else if gateway IP address is specified, use that + * else make a temporary arp cache entry for the client's + * NEW IP/hardware address and use that. + */ + if (dst_override) { + dst.s_addr = dst_override; + if (debug > 1) { + report(LOG_INFO, "reply address override: %s", + inet_ntoa(dst)); + } + } else if (bp->bp_ciaddr.s_addr) { + dst = bp->bp_ciaddr; + } else if (bp->bp_giaddr.s_addr && forward == 0) { + dst = bp->bp_giaddr; + port = bootps_port; + if (debug > 1) { + report(LOG_INFO, "sending reply to gateway %s", + inet_ntoa(dst)); + } + } else { + dst = bp->bp_yiaddr; + ha = bp->bp_chaddr; + len = bp->bp_hlen; + if (len > MAXHADDRLEN) + len = MAXHADDRLEN; + haf = (int) bp->bp_htype; + if (haf == 0) + haf = HTYPE_ETHERNET; + + if (arpmod) { + if (debug > 1) + report(LOG_INFO, "setarp %s - %s", + inet_ntoa(dst), haddrtoa(ha, len)); + setarp(s, &dst, haf, ha, len); + } + } + + if ((forward == 0) && + (bp->bp_siaddr.s_addr == 0)) + { + struct ifreq *ifr; + struct in_addr siaddr; + /* + * If we are originating this reply, we + * need to find our own interface address to + * put in the bp_siaddr field of the reply. + * If this server is multi-homed, pick the + * 'best' interface (the one on the same net + * as the client). Of course, the client may + * be on the other side of a BOOTP gateway... + */ + ifr = getif(s, &dst); + if (ifr) { + struct sockaddr_in *sip; + sip = (struct sockaddr_in *) &(ifr->ifr_addr); + siaddr = sip->sin_addr; + } else { + /* Just use my "official" IP address. */ + siaddr = my_ip_addr; + } + + /* XXX - No need to set bp_giaddr here. */ + + /* Finally, set the server address field. */ + bp->bp_siaddr = siaddr; + } + /* Set up socket address for send. */ + send_addr.sin_family = AF_INET; + send_addr.sin_port = htons(port); + send_addr.sin_addr = dst; + + /* Send reply with same size packet as request used. */ + if (sendto(s, pktbuf, pktlen, 0, + (struct sockaddr *) &send_addr, + sizeof(send_addr)) < 0) + { + report(LOG_ERR, "sendto: %s", get_network_errmsg()); + } +} /* sendreply */ + + +/* nmatch() - now in getif.c */ +/* setarp() - now in hwaddr.c */ + + +/* + * This call checks read access to a file. It returns 0 if the file given + * by "path" exists and is publicly readable. A value of -1 is returned if + * access is not permitted or an error occurs. Successful calls also + * return the file size in bytes using the long pointer "filesize". + * + * The read permission bit for "other" users is checked. This bit must be + * set for tftpd(8) to allow clients to read the file. + */ + +PRIVATE int +chk_access(char *path, int32 *filesize) +{ + struct stat st; + + if ((stat(path, &st) == 0) && (st.st_mode & (S_IREAD >> 6))) { + *filesize = (int32) st.st_size; + return 0; + } else { + return -1; + } +} + + +/* + * Now in dumptab.c : + * dumptab() + * dump_host() + * list_ipaddresses() + */ + +#ifdef VEND_CMU + +/* + * Insert the CMU "vendor" data for the host pointed to by "hp" into the + * bootp packet pointed to by "bp". + */ + +PRIVATE void +dovend_cmu(struct bootp *bp, struct host *hp) +{ + struct cmu_vend *vendp; + struct in_addr_list *taddr; + + /* + * Initialize the entire vendor field to zeroes. + */ + bzero(bp->bp_vend, sizeof(bp->bp_vend)); + + /* + * Fill in vendor information. Subnet mask, default gateway, + * domain name server, ien name server, time server + */ + vendp = (struct cmu_vend *) bp->bp_vend; + strcpy(vendp->v_magic, (char *)vm_cmu); + if (hp->flags.subnet_mask) { + (vendp->v_smask).s_addr = hp->subnet_mask.s_addr; + (vendp->v_flags) |= VF_SMASK; + if (hp->flags.gateway) { + (vendp->v_dgate).s_addr = hp->gateway->addr->s_addr; + } + } + if (hp->flags.domain_server) { + taddr = hp->domain_server; + if (taddr->addrcount > 0) { + (vendp->v_dns1).s_addr = (taddr->addr)[0].s_addr; + if (taddr->addrcount > 1) { + (vendp->v_dns2).s_addr = (taddr->addr)[1].s_addr; + } + } + } + if (hp->flags.name_server) { + taddr = hp->name_server; + if (taddr->addrcount > 0) { + (vendp->v_ins1).s_addr = (taddr->addr)[0].s_addr; + if (taddr->addrcount > 1) { + (vendp->v_ins2).s_addr = (taddr->addr)[1].s_addr; + } + } + } + if (hp->flags.time_server) { + taddr = hp->time_server; + if (taddr->addrcount > 0) { + (vendp->v_ts1).s_addr = (taddr->addr)[0].s_addr; + if (taddr->addrcount > 1) { + (vendp->v_ts2).s_addr = (taddr->addr)[1].s_addr; + } + } + } + /* Log message now done by caller. */ +} /* dovend_cmu */ + +#endif /* VEND_CMU */ + + + +/* + * Insert the RFC1048 vendor data for the host pointed to by "hp" into the + * bootp packet pointed to by "bp". + */ +#define NEED(LEN, MSG) do \ + if (bytesleft < (LEN)) { \ + report(LOG_NOTICE, noroom, \ + hp->hostname->string, MSG); \ + return; \ + } while (0) +PRIVATE void +dovend_rfc1048(struct bootp *bp, struct host *hp, int32 bootsize) +{ + int bytesleft, len; + byte *vp; + + static const char noroom[] = "%s: No room for \"%s\" option"; + + vp = bp->bp_vend; + + if (hp->flags.msg_size) { + pktlen = hp->msg_size; + } else { + /* + * If the request was longer than the official length, build + * a response of that same length where the additional length + * is assumed to be part of the bp_vend (options) area. + */ + if (pktlen > sizeof(*bp)) { + if (debug > 1) + report(LOG_INFO, "request message length=%d", pktlen); + } + /* + * Check whether the request contains the option: + * Maximum DHCP Message Size (RFC1533 sec. 9.8) + * and if so, override the response length with its value. + * This request must lie within the first BP_VEND_LEN + * bytes of the option space. + */ + { + byte *p, *ep; + byte tag, len; + short msgsz = 0; + + p = vp + 4; + ep = p + BP_VEND_LEN - 4; + while (p < ep) { + tag = *p++; + /* Check for tags with no data first. */ + if (tag == TAG_PAD) + continue; + if (tag == TAG_END) + break; + /* Now scan the length byte. */ + len = *p++; + switch (tag) { + case TAG_MAX_MSGSZ: + if (len == 2) { + bcopy(p, (char*)&msgsz, 2); + msgsz = ntohs(msgsz); + } + break; + case TAG_SUBNET_MASK: + /* XXX - Should preserve this if given... */ + break; + } /* swtich */ + p += len; + } + + if (msgsz > sizeof(*bp) + BP_MSG_OVERHEAD) { + if (debug > 1) + report(LOG_INFO, "request has DHCP msglen=%d", msgsz); + pktlen = msgsz - BP_MSG_OVERHEAD; + } + } + } + + if (pktlen < sizeof(*bp)) { + report(LOG_ERR, "invalid response length=%d", pktlen); + pktlen = sizeof(*bp); + } + bytesleft = ((byte*)bp + pktlen) - vp; + if (pktlen > sizeof(*bp)) { + if (debug > 1) + report(LOG_INFO, "extended reply, length=%d, options=%d", + pktlen, bytesleft); + } + + /* Copy in the magic cookie */ + bcopy(vm_rfc1048, vp, 4); + vp += 4; + bytesleft -= 4; + + if (hp->flags.subnet_mask) { + /* always enough room here. */ + *vp++ = TAG_SUBNET_MASK;/* -1 byte */ + *vp++ = 4; /* -1 byte */ + insert_u_long(hp->subnet_mask.s_addr, &vp); /* -4 bytes */ + bytesleft -= 6; /* Fix real count */ + if (hp->flags.gateway) { + (void) insert_ip(TAG_GATEWAY, + hp->gateway, + &vp, &bytesleft); + } + } + if (hp->flags.bootsize) { + /* always enough room here */ + bootsize = (hp->flags.bootsize_auto) ? + ((bootsize + 511) / 512) : (hp->bootsize); /* Round up */ + *vp++ = TAG_BOOT_SIZE; + *vp++ = 2; + *vp++ = (byte) ((bootsize >> 8) & 0xFF); + *vp++ = (byte) (bootsize & 0xFF); + bytesleft -= 4; /* Tag, length, and 16 bit blocksize */ + } + /* + * This one is special: Remaining options go in the ext file. + * Only the subnet_mask, bootsize, and gateway should precede. + */ + if (hp->flags.exten_file) { + /* + * Check for room for exten_file. Add 3 to account for + * TAG_EXTEN_FILE, length, and TAG_END. + */ + len = strlen(hp->exten_file->string); + NEED((len + 3), "ef"); + *vp++ = TAG_EXTEN_FILE; + *vp++ = (byte) (len & 0xFF); + bcopy(hp->exten_file->string, vp, len); + vp += len; + *vp++ = TAG_END; + bytesleft -= len + 3; + return; /* no more options here. */ + } + /* + * The remaining options are inserted by the following + * function (which is shared with bootpef.c). + * Keep back one byte for the TAG_END. + */ + len = dovend_rfc1497(hp, vp, bytesleft - 1); + vp += len; + bytesleft -= len; + + /* There should be at least one byte left. */ + NEED(1, "(end)"); + *vp++ = TAG_END; + bytesleft--; + + /* Log message done by caller. */ + if (bytesleft > 0) { + /* + * Zero out any remaining part of the vendor area. + */ + bzero(vp, bytesleft); + } +} /* dovend_rfc1048 */ +#undef NEED + + +/* + * Now in readfile.c: + * hwlookcmp() + * iplookcmp() + */ + +/* haddrtoa() - now in hwaddr.c */ +/* + * Now in dovend.c: + * insert_ip() + * insert_generic() + * insert_u_long() + */ + +/* get_errmsg() - now in report.c */ + +/* + * Local Variables: + * tab-width: 4 + * c-indent-level: 4 + * c-argdecl-indent: 4 + * c-continued-statement-offset: 4 + * c-continued-brace-offset: -4 + * c-label-offset: -4 + * c-brace-offset: 0 + * End: + */ |