1 /* $NetBSD: bootp.c,v 1.14 1998/02/16 11:10:54 drochner Exp $ */
4 * Copyright (c) 1992 Regents of the University of California.
7 * This software was developed by the Computer Systems Engineering group
8 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
9 * contributed to Berkeley.
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 4. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * @(#) Header: bootp.c,v 1.4 93/09/11 03:13:51 leres Exp (LBL)
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
41 #include <sys/types.h>
42 #include <sys/limits.h>
43 #include <sys/endian.h>
44 #include <netinet/in.h>
45 #include <netinet/in_systm.h>
52 #define DHCP_ENV_NOVENDOR 1 /* do not parse vendor options */
53 #define DHCP_ENV_PXE 10 /* assume pxe vendor options */
54 #define DHCP_ENV_FREEBSD 11 /* assume freebsd vendor options */
55 /* set DHCP_ENV to one of the values above to export dhcp options to kenv */
56 #define DHCP_ENV DHCP_ENV_NO_VENDOR
64 struct in_addr servip;
68 static char vm_rfc1048[4] = VM_RFC1048;
70 static char vm_cmu[4] = VM_CMU;
74 static ssize_t bootpsend(struct iodesc *, void *, size_t);
75 static ssize_t bootprecv(struct iodesc *, void *, size_t, time_t);
76 static int vend_rfc1048(u_char *, u_int);
78 static void vend_cmu(u_char *);
81 #ifdef DHCP_ENV /* export the dhcp response to kenv */
83 static void setenv_(u_char *cp, u_char *ep, struct dhcp_opt *opts);
85 #define setenv_(a, b, c)
89 static char expected_dhcpmsgtype = -1, dhcp_ok;
90 struct in_addr dhcp_serverip;
93 /* Fetch required bootp infomation */
102 u_char header[HEADER_SIZE];
106 u_char header[HEADER_SIZE];
112 printf("bootp: socket=%d\n", sock);
117 if (!(d = socktodesc(sock))) {
118 printf("bootp: bad socket. %d\n", sock);
123 printf("bootp: d=%lx\n", (long)d);
127 bzero(bp, sizeof(*bp));
129 bp->bp_op = BOOTREQUEST;
130 bp->bp_htype = 1; /* 10Mb Ethernet (48 bits) */
132 bp->bp_xid = htonl(d->xid);
133 MACPY(d->myea, bp->bp_chaddr);
134 strncpy(bp->bp_file, bootfile, sizeof(bp->bp_file));
135 bcopy(vm_rfc1048, bp->bp_vend, sizeof(vm_rfc1048));
137 bp->bp_vend[4] = TAG_DHCP_MSGTYPE;
139 bp->bp_vend[6] = DHCPDISCOVER;
142 * If we are booting from PXE, we want to send the string
143 * 'PXEClient' to the DHCP server so you have the option of
144 * only responding to PXE aware dhcp requests.
146 if (flag & BOOTP_PXE) {
147 bp->bp_vend[7] = TAG_CLASSID;
149 bcopy("PXEClient", &bp->bp_vend[9], 9);
150 bp->bp_vend[18] = TAG_PARAM_REQ;
152 bp->bp_vend[20] = TAG_ROOTPATH;
153 bp->bp_vend[21] = TAG_TFTP_SERVER;
154 bp->bp_vend[22] = TAG_HOSTNAME;
155 bp->bp_vend[23] = TAG_SWAPSERVER;
156 bp->bp_vend[24] = TAG_GATEWAY;
157 bp->bp_vend[25] = TAG_SUBNET_MASK;
158 bp->bp_vend[26] = TAG_INTF_MTU;
159 bp->bp_vend[27] = TAG_SERVERID;
160 bp->bp_vend[28] = TAG_END;
162 bp->bp_vend[7] = TAG_END;
164 bp->bp_vend[4] = TAG_END;
167 d->myip.s_addr = INADDR_ANY;
168 d->myport = htons(IPPORT_BOOTPC);
169 d->destip.s_addr = INADDR_BROADCAST;
170 d->destport = htons(IPPORT_BOOTPS);
173 expected_dhcpmsgtype = DHCPOFFER;
178 bootpsend, bp, sizeof(*bp),
179 bootprecv, &rbuf.rbootp, sizeof(rbuf.rbootp))
181 printf("bootp: no reply\n");
188 bp->bp_vend[6] = DHCPREQUEST;
189 bp->bp_vend[7] = TAG_REQ_ADDR;
191 bcopy(&rbuf.rbootp.bp_yiaddr, &bp->bp_vend[9], 4);
192 bp->bp_vend[13] = TAG_SERVERID;
194 bcopy(&dhcp_serverip.s_addr, &bp->bp_vend[15], 4);
195 bp->bp_vend[19] = TAG_LEASETIME;
197 leasetime = htonl(300);
198 bcopy(&leasetime, &bp->bp_vend[21], 4);
199 if (flag & BOOTP_PXE) {
200 bp->bp_vend[25] = TAG_CLASSID;
202 bcopy("PXEClient", &bp->bp_vend[27], 9);
203 bp->bp_vend[36] = TAG_END;
205 bp->bp_vend[25] = TAG_END;
207 expected_dhcpmsgtype = DHCPACK;
210 bootpsend, bp, sizeof(*bp),
211 bootprecv, &rbuf.rbootp, sizeof(rbuf.rbootp))
213 printf("DHCPREQUEST failed\n");
219 myip = d->myip = rbuf.rbootp.bp_yiaddr;
220 servip = rbuf.rbootp.bp_siaddr;
221 if(rootip.s_addr == INADDR_ANY) rootip = servip;
222 bcopy(rbuf.rbootp.bp_file, bootfile, sizeof(bootfile));
223 bootfile[sizeof(bootfile) - 1] = '\0';
226 if (IN_CLASSA(ntohl(myip.s_addr)))
227 netmask = htonl(IN_CLASSA_NET);
228 else if (IN_CLASSB(ntohl(myip.s_addr)))
229 netmask = htonl(IN_CLASSB_NET);
231 netmask = htonl(IN_CLASSC_NET);
234 printf("'native netmask' is %s\n", intoa(netmask));
240 printf("mask: %s\n", intoa(netmask));
243 /* We need a gateway if root is on a different net */
244 if (!SAMENET(myip, rootip, netmask)) {
247 printf("need gateway for root ip\n");
251 /* Toss gateway if on a different net */
252 if (!SAMENET(myip, gateip, netmask)) {
255 printf("gateway ip (%s) bad\n", inet_ntoa(gateip));
260 /* Bump xid so next request will be unique. */
264 /* Transmit a bootp request */
266 bootpsend(d, pkt, len)
275 printf("bootpsend: d=%lx called.\n", (long)d);
279 bp->bp_secs = htons((u_short)(getsecs() - bot));
283 printf("bootpsend: calling sendudp\n");
286 return (sendudp(d, pkt, len));
290 bootprecv(d, pkt, len, tleft)
301 printf("bootp_recvoffer: called\n");
304 n = readudp(d, pkt, len, tleft);
305 if (n == -1 || n < sizeof(struct bootp) - BOOTP_VENDSIZE)
308 bp = (struct bootp *)pkt;
312 printf("bootprecv: checked. bp = 0x%lx, n = %d\n",
315 if (bp->bp_xid != htonl(d->xid)) {
318 printf("bootprecv: expected xid 0x%lx, got 0x%x\n",
319 d->xid, ntohl(bp->bp_xid));
327 printf("bootprecv: got one!\n");
330 /* Suck out vendor info */
331 if (bcmp(vm_rfc1048, bp->bp_vend, sizeof(vm_rfc1048)) == 0) {
332 if(vend_rfc1048(bp->bp_vend, sizeof(bp->bp_vend)) != 0)
335 #ifdef BOOTP_VEND_CMU
336 else if (bcmp(vm_cmu, bp->bp_vend, sizeof(vm_cmu)) == 0)
337 vend_cmu(bp->bp_vend);
340 printf("bootprecv: unknown vendor 0x%lx\n", (long)bp->bp_vend);
349 dhcp_try_rfc1048(u_char *cp, u_int len)
352 expected_dhcpmsgtype = DHCPACK;
353 if (bcmp(vm_rfc1048, cp, sizeof(vm_rfc1048)) == 0) {
354 return (vend_rfc1048(cp, len));
360 vend_rfc1048(cp, len)
371 printf("vend_rfc1048 bootp info. len=%d\n", len);
375 /* Step over magic cookie */
378 setenv_(cp, ep, NULL);
386 if (tag == TAG_SUBNET_MASK) {
387 bcopy(cp, &netmask, sizeof(netmask));
389 if (tag == TAG_GATEWAY) {
390 bcopy(cp, &gateip.s_addr, sizeof(gateip.s_addr));
392 if (tag == TAG_SWAPSERVER) {
393 /* let it override bp_siaddr */
394 bcopy(cp, &rootip.s_addr, sizeof(rootip.s_addr));
396 if (tag == TAG_ROOTPATH) {
397 if ((val = getenv("dhcp.root-path")) == NULL)
398 val = (const char *)cp;
399 strlcpy(rootpath, val, sizeof(rootpath));
401 if (tag == TAG_HOSTNAME) {
402 if ((val = getenv("dhcp.host-name")) == NULL)
403 val = (const char *)cp;
404 strlcpy(hostname, val, sizeof(hostname));
406 if (tag == TAG_INTF_MTU) {
408 if ((val = getenv("dhcp.interface-mtu")) != NULL) {
414 * Do not allow MTU to exceed max IPv4 packet
415 * size, max value of 16-bit word.
417 tmp = strtoul(val, &end, 0);
419 *val == '\0' || *end != '\0' ||
421 printf("%s: bad value: \"%s\", "
423 "dhcp.interface-mtu", val);
425 intf_mtu = (u_int)tmp;
429 intf_mtu = be16dec(cp);
432 if (tag == TAG_DHCP_MSGTYPE) {
433 if(*cp != expected_dhcpmsgtype)
437 if (tag == TAG_SERVERID) {
438 bcopy(cp, &dhcp_serverip.s_addr,
439 sizeof(dhcp_serverip.s_addr));
441 if (tag == TAG_TFTP_SERVER) {
442 bcopy(cp, &tftpip.s_addr,
443 sizeof(tftpip.s_addr));
451 #ifdef BOOTP_VEND_CMU
460 printf("vend_cmu bootp info.\n");
462 vp = (struct cmu_vend *)cp;
464 if (vp->v_smask.s_addr != 0) {
465 netmask = vp->v_smask.s_addr;
467 if (vp->v_dgate.s_addr != 0) {
468 gateip = vp->v_dgate;
475 * Parse DHCP options and store them into kenv variables.
476 * Original code from Danny Braniss, modifications by Luigi Rizzo.
478 * The parser is driven by tables which specify the type and name of
479 * each dhcp option and how it appears in kenv.
480 * The first entry in the list contains the prefix used to set the kenv
481 * name (including the . if needed), the last entry must have a 0 tag.
482 * Entries do not need to be sorted though it helps for readability.
484 * Certain vendor-specific tables can be enabled according to DHCP_ENV.
485 * Set it to 0 if you don't want any.
487 enum opt_fmt { __NONE = 0,
488 __8 = 1, __16 = 2, __32 = 4, /* Unsigned fields, value=size */
489 __IP, /* IPv4 address */
490 __TXT, /* C string */
491 __BYTES, /* byte sequence, printed %02x */
492 __INDIR, /* name=value */
493 __ILIST, /* name=value;name=value ... */
494 __VE, /* vendor specific, recurse */
503 static struct dhcp_opt vndr_opt[] = { /* Vendor Specific Options */
504 #if DHCP_ENV == DHCP_ENV_FREEBSD /* FreeBSD table in the original code */
505 {0, 0, "FreeBSD"}, /* prefix */
506 {1, __TXT, "kernel"},
507 {2, __TXT, "kernelname"},
508 {3, __TXT, "kernel_options"},
510 {5, __TXT, "conf-path"},
511 {6, __TXT, "rc.conf0"},
512 {7, __TXT, "rc.conf1"},
513 {8, __TXT, "rc.conf2"},
514 {9, __TXT, "rc.conf3"},
515 {10, __TXT, "rc.conf4"},
516 {11, __TXT, "rc.conf5"},
517 {12, __TXT, "rc.conf6"},
518 {13, __TXT, "rc.conf7"},
519 {14, __TXT, "rc.conf8"},
520 {15, __TXT, "rc.conf9"},
522 {20, __TXT, "boot.nfsroot.options"},
535 #elif DHCP_ENV == DHCP_ENV_PXE /* some pxe options, RFC4578 */
536 {0, 0, "pxe"}, /* prefix */
537 {93, __16, "system-architecture"},
538 {94, __BYTES, "network-interface"},
539 {97, __BYTES, "machine-identifier"},
540 #else /* default (empty) table */
541 {0, 0, "dhcp.vendor."}, /* prefix */
543 {0, __TXT, "%soption-%d"}
546 static struct dhcp_opt dhcp_opt[] = {
547 /* DHCP Option names, formats and codes, from RFC2132. */
548 {0, 0, "dhcp."}, // prefix
549 {1, __IP, "subnet-mask"},
550 {2, __32, "time-offset"}, /* this is signed */
551 {3, __IP, "routers"},
552 {4, __IP, "time-servers"},
553 {5, __IP, "ien116-name-servers"},
554 {6, __IP, "domain-name-servers"},
555 {7, __IP, "log-servers"},
556 {8, __IP, "cookie-servers"},
557 {9, __IP, "lpr-servers"},
558 {10, __IP, "impress-servers"},
559 {11, __IP, "resource-location-servers"},
560 {12, __TXT, "host-name"},
561 {13, __16, "boot-size"},
562 {14, __TXT, "merit-dump"},
563 {15, __TXT, "domain-name"},
564 {16, __IP, "swap-server"},
565 {17, __TXT, "root-path"},
566 {18, __TXT, "extensions-path"},
567 {19, __8, "ip-forwarding"},
568 {20, __8, "non-local-source-routing"},
569 {21, __IP, "policy-filter"},
570 {22, __16, "max-dgram-reassembly"},
571 {23, __8, "default-ip-ttl"},
572 {24, __32, "path-mtu-aging-timeout"},
573 {25, __16, "path-mtu-plateau-table"},
574 {26, __16, "interface-mtu"},
575 {27, __8, "all-subnets-local"},
576 {28, __IP, "broadcast-address"},
577 {29, __8, "perform-mask-discovery"},
578 {30, __8, "mask-supplier"},
579 {31, __8, "perform-router-discovery"},
580 {32, __IP, "router-solicitation-address"},
581 {33, __IP, "static-routes"},
582 {34, __8, "trailer-encapsulation"},
583 {35, __32, "arp-cache-timeout"},
584 {36, __8, "ieee802-3-encapsulation"},
585 {37, __8, "default-tcp-ttl"},
586 {38, __32, "tcp-keepalive-interval"},
587 {39, __8, "tcp-keepalive-garbage"},
588 {40, __TXT, "nis-domain"},
589 {41, __IP, "nis-servers"},
590 {42, __IP, "ntp-servers"},
591 {43, __VE, "vendor-encapsulated-options"},
592 {44, __IP, "netbios-name-servers"},
593 {45, __IP, "netbios-dd-server"},
594 {46, __8, "netbios-node-type"},
595 {47, __TXT, "netbios-scope"},
596 {48, __IP, "x-font-servers"},
597 {49, __IP, "x-display-managers"},
598 {50, __IP, "dhcp-requested-address"},
599 {51, __32, "dhcp-lease-time"},
600 {52, __8, "dhcp-option-overload"},
601 {53, __8, "dhcp-message-type"},
602 {54, __IP, "dhcp-server-identifier"},
603 {55, __8, "dhcp-parameter-request-list"},
604 {56, __TXT, "dhcp-message"},
605 {57, __16, "dhcp-max-message-size"},
606 {58, __32, "dhcp-renewal-time"},
607 {59, __32, "dhcp-rebinding-time"},
608 {60, __TXT, "vendor-class-identifier"},
609 {61, __TXT, "dhcp-client-identifier"},
610 {64, __TXT, "nisplus-domain"},
611 {65, __IP, "nisplus-servers"},
612 {66, __TXT, "tftp-server-name"},
613 {67, __TXT, "bootfile-name"},
614 {68, __IP, "mobile-ip-home-agent"},
615 {69, __IP, "smtp-server"},
616 {70, __IP, "pop-server"},
617 {71, __IP, "nntp-server"},
618 {72, __IP, "www-server"},
619 {73, __IP, "finger-server"},
620 {74, __IP, "irc-server"},
621 {75, __IP, "streettalk-server"},
622 {76, __IP, "streettalk-directory-assistance-server"},
623 {77, __TXT, "user-class"},
624 {85, __IP, "nds-servers"},
625 {86, __TXT, "nds-tree-name"},
626 {87, __TXT, "nds-context"},
627 {210, __TXT, "authenticate"},
629 /* use the following entries for arbitrary variables */
639 {0, __TXT, "%soption-%d"}
643 * parse a dhcp response, set environment variables translating options
644 * names and values according to the tables above. Also set dhcp.tags
645 * to the list of selected tags.
648 setenv_(u_char *cp, u_char *ep, struct dhcp_opt *opts)
652 char tags[512], *tp; /* the list of tags */
654 #define FLD_SEP ',' /* separator in list of elements */
661 unsigned int size; /* option size */
662 char *vp, *endv, buf[256]; /* the value buffer */
665 tag = *ncp++; /* extract tag and size */
667 cp = ncp; /* current payload */
668 ncp += size; /* point to the next option */
675 for (op = opts+1; op->tag && op->tag != tag; op++)
677 /* if not found we end up on the default entry */
680 * Copy data into the buffer. libstand does not have snprintf so we
681 * need to be careful with sprintf(). With strings, the source is
682 * always <256 char so shorter than the buffer so we are safe; with
683 * other arguments, the longest string is inet_ntoa which is 16 bytes
684 * so we make sure to have always enough room in the string before
689 endv = buf + sizeof(buf) - 1 - 16; /* last valid write position */
693 break; /* should not happen */
695 case __VE: /* recurse, vendor specific */
696 setenv_(cp, cp+size, vndr_opt);
699 case __IP: /* ip address */
700 for (; size > 0 && vp < endv; size -= 4, cp += 4) {
701 struct in_addr in_ip; /* ip addresses */
704 bcopy(cp, &in_ip.s_addr, sizeof(in_ip.s_addr));
705 sprintf(vp, "%s", inet_ntoa(in_ip));
710 case __BYTES: /* opaque byte string */
711 for (; size > 0 && vp < endv; size -= 1, cp += 1) {
712 sprintf(vp, "%02x", *cp);
718 bcopy(cp, buf, size); /* cannot overflow */
724 case __8: /* op->fmt is also the length of each field */
725 for (; size > 0 && vp < endv; size -= op->fmt, cp += op->fmt) {
728 v = (cp[0]<<24) + (cp[1]<<16) + (cp[2]<<8) + cp[3];
729 else if (op->fmt == __16)
730 v = (cp[0]<<8) + cp[1];
735 sprintf(vp, "%u", v);
740 case __INDIR: /* name=value */
741 case __ILIST: /* name=value;name=value... */
742 bcopy(cp, buf, size); /* cannot overflow */
744 for (endv = buf; endv; endv = vp) {
745 u_char *s = NULL; /* semicolon ? */
747 /* skip leading whitespace */
748 while (*endv && strchr(" \t\n\r", *endv))
750 vp = strchr(endv, '='); /* find name=value separator */
754 if (op->fmt == __ILIST && (s = strchr(vp, ';')))
757 vp = s; /* prepare for next round */
759 buf[0] = '\0'; /* option already done */
762 if (tp - tags < sizeof(tags) - 5) { /* add tag to the list */
765 sprintf(tp, "%d", tag);
769 char env[128]; /* the string name */
772 sprintf(env, op->desc, opts[0].desc, tag);
774 sprintf(env, "%s%s", opts[0].desc, op->desc);
776 * Do not replace existing values in the environment, so that
777 * locally-obtained values can override server-provided values.
783 char env[128]; /* the string name */
784 sprintf(env, "%stags", opts[0].desc);
785 setenv(env, tags, 1);
788 #endif /* additional dhcp */