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/endian.h>
43 #include <netinet/in.h>
44 #include <netinet/in_systm.h>
51 #define DHCP_ENV_NOVENDOR 1 /* do not parse vendor options */
52 #define DHCP_ENV_PXE 10 /* assume pxe vendor options */
53 #define DHCP_ENV_FREEBSD 11 /* assume freebsd vendor options */
54 /* set DHCP_ENV to one of the values above to export dhcp options to kenv */
55 #define DHCP_ENV DHCP_ENV_NO_VENDOR
63 struct in_addr servip;
65 static n_long nmask, smask;
69 static char vm_rfc1048[4] = VM_RFC1048;
71 static char vm_cmu[4] = VM_CMU;
75 static ssize_t bootpsend(struct iodesc *, void *, size_t);
76 static ssize_t bootprecv(struct iodesc *, void *, size_t, time_t);
77 static int vend_rfc1048(u_char *, u_int);
79 static void vend_cmu(u_char *);
82 #ifdef DHCP_ENV /* export the dhcp response to kenv */
84 static void setenv_(u_char *cp, u_char *ep, struct dhcp_opt *opts);
86 #define setenv_(a, b, c)
90 static char expected_dhcpmsgtype = -1, dhcp_ok;
91 struct in_addr dhcp_serverip;
94 /* Fetch required bootp infomation */
103 u_char header[HEADER_SIZE];
107 u_char header[HEADER_SIZE];
113 printf("bootp: socket=%d\n", sock);
118 if (!(d = socktodesc(sock))) {
119 printf("bootp: bad socket. %d\n", sock);
124 printf("bootp: d=%lx\n", (long)d);
128 bzero(bp, sizeof(*bp));
130 bp->bp_op = BOOTREQUEST;
131 bp->bp_htype = 1; /* 10Mb Ethernet (48 bits) */
133 bp->bp_xid = htonl(d->xid);
134 MACPY(d->myea, bp->bp_chaddr);
135 strncpy(bp->bp_file, bootfile, sizeof(bp->bp_file));
136 bcopy(vm_rfc1048, bp->bp_vend, sizeof(vm_rfc1048));
138 bp->bp_vend[4] = TAG_DHCP_MSGTYPE;
140 bp->bp_vend[6] = DHCPDISCOVER;
143 * If we are booting from PXE, we want to send the string
144 * 'PXEClient' to the DHCP server so you have the option of
145 * only responding to PXE aware dhcp requests.
147 if (flag & BOOTP_PXE) {
148 bp->bp_vend[7] = TAG_CLASSID;
150 bcopy("PXEClient", &bp->bp_vend[9], 9);
151 bp->bp_vend[18] = TAG_PARAM_REQ;
153 bp->bp_vend[20] = TAG_ROOTPATH;
154 bp->bp_vend[21] = TAG_TFTP_SERVER;
155 bp->bp_vend[22] = TAG_HOSTNAME;
156 bp->bp_vend[23] = TAG_SWAPSERVER;
157 bp->bp_vend[24] = TAG_GATEWAY;
158 bp->bp_vend[25] = TAG_SUBNET_MASK;
159 bp->bp_vend[26] = TAG_INTF_MTU;
160 bp->bp_vend[27] = TAG_SERVERID;
161 bp->bp_vend[28] = TAG_END;
163 bp->bp_vend[7] = TAG_END;
165 bp->bp_vend[4] = TAG_END;
168 d->myip.s_addr = INADDR_ANY;
169 d->myport = htons(IPPORT_BOOTPC);
170 d->destip.s_addr = INADDR_BROADCAST;
171 d->destport = htons(IPPORT_BOOTPS);
174 expected_dhcpmsgtype = DHCPOFFER;
179 bootpsend, bp, sizeof(*bp),
180 bootprecv, &rbuf.rbootp, sizeof(rbuf.rbootp))
182 printf("bootp: no reply\n");
189 bp->bp_vend[6] = DHCPREQUEST;
190 bp->bp_vend[7] = TAG_REQ_ADDR;
192 bcopy(&rbuf.rbootp.bp_yiaddr, &bp->bp_vend[9], 4);
193 bp->bp_vend[13] = TAG_SERVERID;
195 bcopy(&dhcp_serverip.s_addr, &bp->bp_vend[15], 4);
196 bp->bp_vend[19] = TAG_LEASETIME;
198 leasetime = htonl(300);
199 bcopy(&leasetime, &bp->bp_vend[21], 4);
200 if (flag & BOOTP_PXE) {
201 bp->bp_vend[25] = TAG_CLASSID;
203 bcopy("PXEClient", &bp->bp_vend[27], 9);
204 bp->bp_vend[36] = TAG_END;
206 bp->bp_vend[25] = TAG_END;
208 expected_dhcpmsgtype = DHCPACK;
211 bootpsend, bp, sizeof(*bp),
212 bootprecv, &rbuf.rbootp, sizeof(rbuf.rbootp))
214 printf("DHCPREQUEST failed\n");
220 myip = d->myip = rbuf.rbootp.bp_yiaddr;
221 servip = rbuf.rbootp.bp_siaddr;
222 if(rootip.s_addr == INADDR_ANY) rootip = servip;
223 bcopy(rbuf.rbootp.bp_file, bootfile, sizeof(bootfile));
224 bootfile[sizeof(bootfile) - 1] = '\0';
226 if (IN_CLASSA(ntohl(myip.s_addr)))
227 nmask = htonl(IN_CLASSA_NET);
228 else if (IN_CLASSB(ntohl(myip.s_addr)))
229 nmask = htonl(IN_CLASSB_NET);
231 nmask = htonl(IN_CLASSC_NET);
234 printf("'native netmask' is %s\n", intoa(nmask));
237 /* Check subnet mask against net mask; toss if bogus */
238 if ((nmask & smask) != nmask) {
241 printf("subnet mask (%s) bad\n", intoa(smask));
246 /* Get subnet (or natural net) mask */
252 printf("mask: %s\n", intoa(netmask));
255 /* We need a gateway if root is on a different net */
256 if (!SAMENET(myip, rootip, netmask)) {
259 printf("need gateway for root ip\n");
263 /* Toss gateway if on a different net */
264 if (!SAMENET(myip, gateip, netmask)) {
267 printf("gateway ip (%s) bad\n", inet_ntoa(gateip));
272 /* Bump xid so next request will be unique. */
276 /* Transmit a bootp request */
278 bootpsend(d, pkt, len)
287 printf("bootpsend: d=%lx called.\n", (long)d);
291 bp->bp_secs = htons((u_short)(getsecs() - bot));
295 printf("bootpsend: calling sendudp\n");
298 return (sendudp(d, pkt, len));
302 bootprecv(d, pkt, len, tleft)
313 printf("bootp_recvoffer: called\n");
316 n = readudp(d, pkt, len, tleft);
317 if (n == -1 || n < sizeof(struct bootp) - BOOTP_VENDSIZE)
320 bp = (struct bootp *)pkt;
324 printf("bootprecv: checked. bp = 0x%lx, n = %d\n",
327 if (bp->bp_xid != htonl(d->xid)) {
330 printf("bootprecv: expected xid 0x%lx, got 0x%x\n",
331 d->xid, ntohl(bp->bp_xid));
339 printf("bootprecv: got one!\n");
342 /* Suck out vendor info */
343 if (bcmp(vm_rfc1048, bp->bp_vend, sizeof(vm_rfc1048)) == 0) {
344 if(vend_rfc1048(bp->bp_vend, sizeof(bp->bp_vend)) != 0)
347 #ifdef BOOTP_VEND_CMU
348 else if (bcmp(vm_cmu, bp->bp_vend, sizeof(vm_cmu)) == 0)
349 vend_cmu(bp->bp_vend);
352 printf("bootprecv: unknown vendor 0x%lx\n", (long)bp->bp_vend);
361 vend_rfc1048(cp, len)
372 printf("vend_rfc1048 bootp info. len=%d\n", len);
376 /* Step over magic cookie */
379 setenv_(cp, ep, NULL);
387 if (tag == TAG_SUBNET_MASK) {
388 bcopy(cp, &smask, sizeof(smask));
390 if (tag == TAG_GATEWAY) {
391 bcopy(cp, &gateip.s_addr, sizeof(gateip.s_addr));
393 if (tag == TAG_SWAPSERVER) {
394 /* let it override bp_siaddr */
395 bcopy(cp, &rootip.s_addr, sizeof(rootip.s_addr));
397 if (tag == TAG_ROOTPATH) {
398 if ((val = getenv("dhcp.root-path")) == NULL)
399 val = (const char *)cp;
400 strlcpy(rootpath, val, sizeof(rootpath));
402 if (tag == TAG_HOSTNAME) {
403 if ((val = getenv("dhcp.host-name")) == NULL)
404 val = (const char *)cp;
405 strlcpy(hostname, val, sizeof(hostname));
407 if (tag == TAG_INTF_MTU) {
408 if ((val = getenv("dhcp.interface-mtu")) != NULL) {
409 intf_mtu = (u_int)strtoul(val, NULL, 0);
411 intf_mtu = be16dec(cp);
415 if (tag == TAG_DHCP_MSGTYPE) {
416 if(*cp != expected_dhcpmsgtype)
420 if (tag == TAG_SERVERID) {
421 bcopy(cp, &dhcp_serverip.s_addr,
422 sizeof(dhcp_serverip.s_addr));
424 if (tag == TAG_TFTP_SERVER) {
425 bcopy(cp, &tftpip.s_addr,
426 sizeof(tftpip.s_addr));
434 #ifdef BOOTP_VEND_CMU
443 printf("vend_cmu bootp info.\n");
445 vp = (struct cmu_vend *)cp;
447 if (vp->v_smask.s_addr != 0) {
448 smask = vp->v_smask.s_addr;
450 if (vp->v_dgate.s_addr != 0) {
451 gateip = vp->v_dgate;
458 * Parse DHCP options and store them into kenv variables.
459 * Original code from Danny Braniss, modifications by Luigi Rizzo.
461 * The parser is driven by tables which specify the type and name of
462 * each dhcp option and how it appears in kenv.
463 * The first entry in the list contains the prefix used to set the kenv
464 * name (including the . if needed), the last entry must have a 0 tag.
465 * Entries do not need to be sorted though it helps for readability.
467 * Certain vendor-specific tables can be enabled according to DHCP_ENV.
468 * Set it to 0 if you don't want any.
470 enum opt_fmt { __NONE = 0,
471 __8 = 1, __16 = 2, __32 = 4, /* Unsigned fields, value=size */
472 __IP, /* IPv4 address */
473 __TXT, /* C string */
474 __BYTES, /* byte sequence, printed %02x */
475 __INDIR, /* name=value */
476 __ILIST, /* name=value;name=value ... */
477 __VE, /* vendor specific, recurse */
486 static struct dhcp_opt vndr_opt[] = { /* Vendor Specific Options */
487 #if DHCP_ENV == DHCP_ENV_FREEBSD /* FreeBSD table in the original code */
488 {0, 0, "FreeBSD"}, /* prefix */
489 {1, __TXT, "kernel"},
490 {2, __TXT, "kernelname"},
491 {3, __TXT, "kernel_options"},
493 {5, __TXT, "conf-path"},
494 {6, __TXT, "rc.conf0"},
495 {7, __TXT, "rc.conf1"},
496 {8, __TXT, "rc.conf2"},
497 {9, __TXT, "rc.conf3"},
498 {10, __TXT, "rc.conf4"},
499 {11, __TXT, "rc.conf5"},
500 {12, __TXT, "rc.conf6"},
501 {13, __TXT, "rc.conf7"},
502 {14, __TXT, "rc.conf8"},
503 {15, __TXT, "rc.conf9"},
505 {20, __TXT, "boot.nfsroot.options"},
518 #elif DHCP_ENV == DHCP_ENV_PXE /* some pxe options, RFC4578 */
519 {0, 0, "pxe"}, /* prefix */
520 {93, __16, "system-architecture"},
521 {94, __BYTES, "network-interface"},
522 {97, __BYTES, "machine-identifier"},
523 #else /* default (empty) table */
524 {0, 0, "dhcp.vendor."}, /* prefix */
526 {0, __TXT, "%soption-%d"}
529 static struct dhcp_opt dhcp_opt[] = {
530 /* DHCP Option names, formats and codes, from RFC2132. */
531 {0, 0, "dhcp."}, // prefix
532 {1, __IP, "subnet-mask"},
533 {2, __32, "time-offset"}, /* this is signed */
534 {3, __IP, "routers"},
535 {4, __IP, "time-servers"},
536 {5, __IP, "ien116-name-servers"},
537 {6, __IP, "domain-name-servers"},
538 {7, __IP, "log-servers"},
539 {8, __IP, "cookie-servers"},
540 {9, __IP, "lpr-servers"},
541 {10, __IP, "impress-servers"},
542 {11, __IP, "resource-location-servers"},
543 {12, __TXT, "host-name"},
544 {13, __16, "boot-size"},
545 {14, __TXT, "merit-dump"},
546 {15, __TXT, "domain-name"},
547 {16, __IP, "swap-server"},
548 {17, __TXT, "root-path"},
549 {18, __TXT, "extensions-path"},
550 {19, __8, "ip-forwarding"},
551 {20, __8, "non-local-source-routing"},
552 {21, __IP, "policy-filter"},
553 {22, __16, "max-dgram-reassembly"},
554 {23, __8, "default-ip-ttl"},
555 {24, __32, "path-mtu-aging-timeout"},
556 {25, __16, "path-mtu-plateau-table"},
557 {26, __16, "interface-mtu"},
558 {27, __8, "all-subnets-local"},
559 {28, __IP, "broadcast-address"},
560 {29, __8, "perform-mask-discovery"},
561 {30, __8, "mask-supplier"},
562 {31, __8, "perform-router-discovery"},
563 {32, __IP, "router-solicitation-address"},
564 {33, __IP, "static-routes"},
565 {34, __8, "trailer-encapsulation"},
566 {35, __32, "arp-cache-timeout"},
567 {36, __8, "ieee802-3-encapsulation"},
568 {37, __8, "default-tcp-ttl"},
569 {38, __32, "tcp-keepalive-interval"},
570 {39, __8, "tcp-keepalive-garbage"},
571 {40, __TXT, "nis-domain"},
572 {41, __IP, "nis-servers"},
573 {42, __IP, "ntp-servers"},
574 {43, __VE, "vendor-encapsulated-options"},
575 {44, __IP, "netbios-name-servers"},
576 {45, __IP, "netbios-dd-server"},
577 {46, __8, "netbios-node-type"},
578 {47, __TXT, "netbios-scope"},
579 {48, __IP, "x-font-servers"},
580 {49, __IP, "x-display-managers"},
581 {50, __IP, "dhcp-requested-address"},
582 {51, __32, "dhcp-lease-time"},
583 {52, __8, "dhcp-option-overload"},
584 {53, __8, "dhcp-message-type"},
585 {54, __IP, "dhcp-server-identifier"},
586 {55, __8, "dhcp-parameter-request-list"},
587 {56, __TXT, "dhcp-message"},
588 {57, __16, "dhcp-max-message-size"},
589 {58, __32, "dhcp-renewal-time"},
590 {59, __32, "dhcp-rebinding-time"},
591 {60, __TXT, "vendor-class-identifier"},
592 {61, __TXT, "dhcp-client-identifier"},
593 {64, __TXT, "nisplus-domain"},
594 {65, __IP, "nisplus-servers"},
595 {66, __TXT, "tftp-server-name"},
596 {67, __TXT, "bootfile-name"},
597 {68, __IP, "mobile-ip-home-agent"},
598 {69, __IP, "smtp-server"},
599 {70, __IP, "pop-server"},
600 {71, __IP, "nntp-server"},
601 {72, __IP, "www-server"},
602 {73, __IP, "finger-server"},
603 {74, __IP, "irc-server"},
604 {75, __IP, "streettalk-server"},
605 {76, __IP, "streettalk-directory-assistance-server"},
606 {77, __TXT, "user-class"},
607 {85, __IP, "nds-servers"},
608 {86, __TXT, "nds-tree-name"},
609 {87, __TXT, "nds-context"},
610 {210, __TXT, "authenticate"},
612 /* use the following entries for arbitrary variables */
622 {0, __TXT, "%soption-%d"}
626 * parse a dhcp response, set environment variables translating options
627 * names and values according to the tables above. Also set dhcp.tags
628 * to the list of selected tags.
631 setenv_(u_char *cp, u_char *ep, struct dhcp_opt *opts)
635 char tags[512], *tp; /* the list of tags */
637 #define FLD_SEP ',' /* separator in list of elements */
644 unsigned int size; /* option size */
645 char *vp, *endv, buf[256]; /* the value buffer */
648 tag = *ncp++; /* extract tag and size */
650 cp = ncp; /* current payload */
651 ncp += size; /* point to the next option */
658 for (op = opts+1; op->tag && op->tag != tag; op++)
660 /* if not found we end up on the default entry */
663 * Copy data into the buffer. libstand does not have snprintf so we
664 * need to be careful with sprintf(). With strings, the source is
665 * always <256 char so shorter than the buffer so we are safe; with
666 * other arguments, the longest string is inet_ntoa which is 16 bytes
667 * so we make sure to have always enough room in the string before
672 endv = buf + sizeof(buf) - 1 - 16; /* last valid write position */
676 break; /* should not happen */
678 case __VE: /* recurse, vendor specific */
679 setenv_(cp, cp+size, vndr_opt);
682 case __IP: /* ip address */
683 for (; size > 0 && vp < endv; size -= 4, cp += 4) {
684 struct in_addr in_ip; /* ip addresses */
687 bcopy(cp, &in_ip.s_addr, sizeof(in_ip.s_addr));
688 sprintf(vp, "%s", inet_ntoa(in_ip));
693 case __BYTES: /* opaque byte string */
694 for (; size > 0 && vp < endv; size -= 1, cp += 1) {
695 sprintf(vp, "%02x", *cp);
701 bcopy(cp, buf, size); /* cannot overflow */
707 case __8: /* op->fmt is also the length of each field */
708 for (; size > 0 && vp < endv; size -= op->fmt, cp += op->fmt) {
711 v = (cp[0]<<24) + (cp[1]<<16) + (cp[2]<<8) + cp[3];
712 else if (op->fmt == __16)
713 v = (cp[0]<<8) + cp[1];
718 sprintf(vp, "%u", v);
723 case __INDIR: /* name=value */
724 case __ILIST: /* name=value;name=value... */
725 bcopy(cp, buf, size); /* cannot overflow */
727 for (endv = buf; endv; endv = vp) {
728 u_char *s = NULL; /* semicolon ? */
730 /* skip leading whitespace */
731 while (*endv && strchr(" \t\n\r", *endv))
733 vp = strchr(endv, '='); /* find name=value separator */
737 if (op->fmt == __ILIST && (s = strchr(vp, ';')))
740 vp = s; /* prepare for next round */
742 buf[0] = '\0'; /* option already done */
745 if (tp - tags < sizeof(tags) - 5) { /* add tag to the list */
748 sprintf(tp, "%d", tag);
752 char env[128]; /* the string name */
755 sprintf(env, op->desc, opts[0].desc, tag);
757 sprintf(env, "%s%s", opts[0].desc, op->desc);
759 * Do not replace existing values in the environment, so that
760 * locally-obtained values can override server-provided values.
766 char env[128]; /* the string name */
767 sprintf(env, "%stags", opts[0].desc);
768 setenv(env, tags, 1);
771 #endif /* additional dhcp */