1 /*
2 * Copyright (c) 1992 Regents of the University of California.
3 * All rights reserved.
4 *
5 * This software was developed by the Computer Systems Engineering group
6 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
7 * contributed to Berkeley.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34 #include <sys/cdefs.h>
35
36 #include <stddef.h>
37 #include <sys/types.h>
38 #include <sys/limits.h>
39 #include <sys/endian.h>
40 #include <netinet/in.h>
41 #include <netinet/in_systm.h>
42
43 #include <string.h>
44
45 #define BOOTP_DEBUGxx
46 #define SUPPORT_DHCP
47
48 #define DHCP_ENV_NOVENDOR 1 /* do not parse vendor options */
49 #define DHCP_ENV_PXE 10 /* assume pxe vendor options */
50 #define DHCP_ENV_FREEBSD 11 /* assume freebsd vendor options */
51 /* set DHCP_ENV to one of the values above to export dhcp options to kenv */
52 #define DHCP_ENV DHCP_ENV_NO_VENDOR
53
54 #include "stand.h"
55 #include "net.h"
56 #include "netif.h"
57 #include "bootp.h"
58
59
60 struct in_addr servip;
61
62 static time_t bot;
63
64 static char vm_rfc1048[4] = VM_RFC1048;
65 #ifdef BOOTP_VEND_CMU
66 static char vm_cmu[4] = VM_CMU;
67 #endif
68
69 /* Local forwards */
70 static ssize_t bootpsend(struct iodesc *, void *, size_t);
71 static ssize_t bootprecv(struct iodesc *, void **, void **, time_t, void *);
72 static int vend_rfc1048(uchar_t *, uint_t);
73 #ifdef BOOTP_VEND_CMU
74 static void vend_cmu(uchar_t *);
75 #endif
76
77 #ifdef DHCP_ENV /* export the dhcp response to kenv */
78 struct dhcp_opt;
79 static void setenv_(uchar_t *cp, uchar_t *ep, struct dhcp_opt *opts);
80 #else
81 #define setenv_(a, b, c)
82 #endif
83
84 #ifdef SUPPORT_DHCP
85 static char expected_dhcpmsgtype = -1, dhcp_ok;
86 struct in_addr dhcp_serverip;
87 #endif
88 struct bootp *bootp_response;
89 size_t bootp_response_size;
90
91 static void
bootp_fill_request(unsigned char * bp_vend)92 bootp_fill_request(unsigned char *bp_vend)
93 {
94 /*
95 * We are booting from PXE, we want to send the string
96 * 'PXEClient' to the DHCP server so you have the option of
97 * only responding to PXE aware dhcp requests.
98 */
99 bp_vend[0] = TAG_CLASSID;
100 bp_vend[1] = 9;
101 bcopy("PXEClient", &bp_vend[2], 9);
102 bp_vend[11] = TAG_USER_CLASS;
103 /* len of each user class + number of user class */
104 bp_vend[12] = 8;
105 /* len of the first user class */
106 bp_vend[13] = 7;
107 bcopy("illumos", &bp_vend[14], 7);
108 bp_vend[21] = TAG_PARAM_REQ;
109 bp_vend[22] = 7;
110 bp_vend[23] = TAG_SUBNET_MASK;
111 bp_vend[24] = TAG_GATEWAY;
112 bp_vend[25] = TAG_HOSTNAME;
113 bp_vend[26] = TAG_SWAPSERVER;
114 bp_vend[27] = TAG_ROOTPATH;
115 bp_vend[28] = TAG_INTF_MTU;
116 bp_vend[29] = TAG_SERVERID;
117 bp_vend[30] = TAG_END;
118 }
119
120 /* Fetch required bootp infomation */
121 void
bootp(int sock)122 bootp(int sock)
123 {
124 void *pkt;
125 struct iodesc *d;
126 struct bootp *bp;
127 struct {
128 uchar_t header[HEADER_SIZE];
129 struct bootp wbootp;
130 } wbuf;
131 struct bootp *rbootp;
132
133 #ifdef BOOTP_DEBUG
134 if (debug)
135 printf("bootp: socket=%d\n", sock);
136 #endif
137 if (!bot)
138 bot = getsecs();
139
140 if (!(d = socktodesc(sock))) {
141 printf("bootp: bad socket. %d\n", sock);
142 return;
143 }
144 #ifdef BOOTP_DEBUG
145 if (debug)
146 printf("bootp: d=%lx\n", (long)d);
147 #endif
148
149 bp = &wbuf.wbootp;
150 bzero(bp, sizeof (*bp));
151
152 bp->bp_op = BOOTREQUEST;
153 bp->bp_htype = 1; /* 10Mb Ethernet (48 bits) */
154 bp->bp_hlen = 6;
155 bp->bp_xid = htonl(d->xid);
156 MACPY(d->myea, bp->bp_chaddr);
157 strncpy(bp->bp_file, bootfile, sizeof (bp->bp_file));
158 bcopy(vm_rfc1048, bp->bp_vend, sizeof (vm_rfc1048));
159 #ifdef SUPPORT_DHCP
160 bp->bp_vend[4] = TAG_DHCP_MSGTYPE;
161 bp->bp_vend[5] = 1;
162 bp->bp_vend[6] = DHCPDISCOVER;
163 bootp_fill_request(&bp->bp_vend[7]);
164 #else
165 bp->bp_vend[4] = TAG_END;
166 #endif
167
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);
172
173 #ifdef SUPPORT_DHCP
174 expected_dhcpmsgtype = DHCPOFFER;
175 dhcp_ok = 0;
176 #endif
177
178 if (sendrecv(d, bootpsend, bp, sizeof (*bp),
179 bootprecv, &pkt, (void **)&rbootp, NULL) == -1) {
180 printf("bootp: no reply\n");
181 return;
182 }
183
184 #ifdef SUPPORT_DHCP
185 if (dhcp_ok) {
186 uint32_t leasetime;
187 bp->bp_vend[6] = DHCPREQUEST;
188 bp->bp_vend[7] = TAG_REQ_ADDR;
189 bp->bp_vend[8] = 4;
190 bcopy(&rbootp->bp_yiaddr, &bp->bp_vend[9], 4);
191 bp->bp_vend[13] = TAG_SERVERID;
192 bp->bp_vend[14] = 4;
193 bcopy(&dhcp_serverip.s_addr, &bp->bp_vend[15], 4);
194 bp->bp_vend[19] = TAG_LEASETIME;
195 bp->bp_vend[20] = 4;
196 leasetime = htonl(300);
197 bcopy(&leasetime, &bp->bp_vend[21], 4);
198 bootp_fill_request(&bp->bp_vend[25]);
199
200 expected_dhcpmsgtype = DHCPACK;
201
202 free(pkt);
203 if (sendrecv(d, bootpsend, bp, sizeof (*bp),
204 bootprecv, &pkt, (void **)&rbootp, NULL) == -1) {
205 printf("DHCPREQUEST failed\n");
206 return;
207 }
208 }
209 #endif
210
211 myip = d->myip = rbootp->bp_yiaddr;
212 servip = rbootp->bp_siaddr;
213 if (rootip.s_addr == INADDR_ANY)
214 rootip = servip;
215 bcopy(rbootp->bp_file, bootfile, sizeof (bootfile));
216 bootfile[sizeof (bootfile) - 1] = '\0';
217
218 if (!netmask) {
219 if (IN_CLASSA(ntohl(myip.s_addr)))
220 netmask = htonl(IN_CLASSA_NET);
221 else if (IN_CLASSB(ntohl(myip.s_addr)))
222 netmask = htonl(IN_CLASSB_NET);
223 else
224 netmask = htonl(IN_CLASSC_NET);
225 #ifdef BOOTP_DEBUG
226 if (debug)
227 printf("'native netmask' is %s\n", intoa(netmask));
228 #endif
229 }
230
231 #ifdef BOOTP_DEBUG
232 if (debug)
233 printf("mask: %s\n", intoa(netmask));
234 #endif
235
236 /* We need a gateway if root is on a different net */
237 if (!SAMENET(myip, rootip, netmask)) {
238 #ifdef BOOTP_DEBUG
239 if (debug)
240 printf("need gateway for root ip\n");
241 #endif
242 }
243
244 /* Toss gateway if on a different net */
245 if (!SAMENET(myip, gateip, netmask)) {
246 #ifdef BOOTP_DEBUG
247 if (debug)
248 printf("gateway ip (%s) bad\n", inet_ntoa(gateip));
249 #endif
250 gateip.s_addr = 0;
251 }
252
253 /* Bump xid so next request will be unique. */
254 ++d->xid;
255 free(pkt);
256 }
257
258 /* Transmit a bootp request */
259 static ssize_t
bootpsend(struct iodesc * d,void * pkt,size_t len)260 bootpsend(struct iodesc *d, void *pkt, size_t len)
261 {
262 struct bootp *bp;
263
264 #ifdef BOOTP_DEBUG
265 if (debug)
266 printf("bootpsend: d=%lx called.\n", (long)d);
267 #endif
268
269 bp = pkt;
270 bp->bp_secs = htons((ushort_t)(getsecs() - bot));
271
272 #ifdef BOOTP_DEBUG
273 if (debug)
274 printf("bootpsend: calling sendudp\n");
275 #endif
276
277 return (sendudp(d, pkt, len));
278 }
279
280 static ssize_t
bootprecv(struct iodesc * d,void ** pkt,void ** payload,time_t tleft,void * extra __unused)281 bootprecv(struct iodesc *d, void **pkt, void **payload, time_t tleft,
282 void *extra __unused)
283 {
284 ssize_t n;
285 struct bootp *bp;
286 void *ptr;
287
288 #ifdef BOOTP_DEBUG
289 if (debug)
290 printf("bootp_recvoffer: called\n");
291 #endif
292
293 ptr = NULL;
294 n = readudp(d, &ptr, (void **)&bp, tleft);
295 if (n == -1 || n < sizeof (struct bootp) - BOOTP_VENDSIZE)
296 goto bad;
297
298 #ifdef BOOTP_DEBUG
299 if (debug)
300 printf("bootprecv: checked. bp = %p, n = %zd\n", bp, n);
301 #endif
302 if (bp->bp_xid != htonl(d->xid)) {
303 #ifdef BOOTP_DEBUG
304 if (debug) {
305 printf("bootprecv: expected xid 0x%lx, got 0x%x\n",
306 d->xid, ntohl(bp->bp_xid));
307 }
308 #endif
309 goto bad;
310 }
311
312 #ifdef BOOTP_DEBUG
313 if (debug)
314 printf("bootprecv: got one!\n");
315 #endif
316
317 /* Suck out vendor info */
318 if (bcmp(vm_rfc1048, bp->bp_vend, sizeof (vm_rfc1048)) == 0) {
319 int vsize = n - offsetof(struct bootp, bp_vend);
320 if (vend_rfc1048(bp->bp_vend, vsize) != 0)
321 goto bad;
322
323 /* Save copy of bootp reply or DHCP ACK message */
324 if (bp->bp_op == BOOTREPLY &&
325 ((dhcp_ok == 1 && expected_dhcpmsgtype == DHCPACK) ||
326 dhcp_ok == 0)) {
327 free(bootp_response);
328 bootp_response = malloc(n);
329 if (bootp_response != NULL) {
330 bootp_response_size = n;
331 bcopy(bp, bootp_response, bootp_response_size);
332 }
333 }
334 }
335 #ifdef BOOTP_VEND_CMU
336 else if (bcmp(vm_cmu, bp->bp_vend, sizeof (vm_cmu)) == 0)
337 vend_cmu(bp->bp_vend);
338 #endif
339 else
340 printf("bootprecv: unknown vendor 0x%lx\n", (long)bp->bp_vend);
341
342 *pkt = ptr;
343 *payload = bp;
344 return (n);
345 bad:
346 free(ptr);
347 errno = 0;
348 return (-1);
349 }
350
351 static int
vend_rfc1048(uchar_t * cp,uint_t len)352 vend_rfc1048(uchar_t *cp, uint_t len)
353 {
354 uchar_t *ep;
355 int size;
356 uchar_t tag;
357 const char *val;
358
359 #ifdef BOOTP_DEBUG
360 if (debug)
361 printf("vend_rfc1048 bootp info. len=%d\n", len);
362 #endif
363 ep = cp + len;
364
365 /* Step over magic cookie */
366 cp += sizeof (int);
367
368 setenv_(cp, ep, NULL);
369
370 while (cp < ep) {
371 tag = *cp++;
372 size = *cp++;
373 if (tag == TAG_END)
374 break;
375
376 if (tag == TAG_SUBNET_MASK) {
377 bcopy(cp, &netmask, sizeof (netmask));
378 }
379 if (tag == TAG_GATEWAY) {
380 bcopy(cp, &gateip.s_addr, sizeof (gateip.s_addr));
381 }
382 if (tag == TAG_SWAPSERVER) {
383 /* let it override bp_siaddr */
384 bcopy(cp, &rootip.s_addr, sizeof (rootip.s_addr));
385 }
386 if (tag == TAG_ROOTPATH) {
387 if ((val = getenv("dhcp.root-path")) == NULL)
388 val = (const char *)cp;
389 strlcpy(rootpath, val, sizeof (rootpath));
390 }
391 if (tag == TAG_HOSTNAME) {
392 if ((val = getenv("dhcp.host-name")) == NULL)
393 val = (const char *)cp;
394 strlcpy(hostname, val, sizeof (hostname));
395 }
396 if (tag == TAG_INTF_MTU) {
397 intf_mtu = 0;
398 if ((val = getenv("dhcp.interface-mtu")) != NULL) {
399 unsigned long tmp;
400 char *end;
401
402 errno = 0;
403 /*
404 * Do not allow MTU to exceed max IPv4 packet
405 * size, max value of 16-bit word.
406 */
407 tmp = strtoul(val, &end, 0);
408 if (errno != 0 ||
409 *val == '\0' || *end != '\0' ||
410 tmp > USHRT_MAX) {
411 printf("%s: bad value: \"%s\", "
412 "ignoring\n",
413 "dhcp.interface-mtu", val);
414 } else {
415 intf_mtu = (uint_t)tmp;
416 }
417 }
418 if (intf_mtu == 0)
419 intf_mtu = be16dec(cp);
420 }
421 #ifdef SUPPORT_DHCP
422 if (tag == TAG_DHCP_MSGTYPE) {
423 if (*cp != expected_dhcpmsgtype)
424 return (-1);
425 dhcp_ok = 1;
426 }
427 if (tag == TAG_SERVERID) {
428 bcopy(cp, &dhcp_serverip.s_addr,
429 sizeof (dhcp_serverip.s_addr));
430 }
431 #endif
432 cp += size;
433 }
434 return (0);
435 }
436
437 #ifdef BOOTP_VEND_CMU
438 static void
vend_cmu(uchar_t * cp)439 vend_cmu(uchar_t *cp)
440 {
441 struct cmu_vend *vp;
442
443 #ifdef BOOTP_DEBUG
444 if (debug)
445 printf("vend_cmu bootp info.\n");
446 #endif
447 vp = (struct cmu_vend *)cp;
448
449 if (vp->v_smask.s_addr != 0) {
450 netmask = vp->v_smask.s_addr;
451 }
452 if (vp->v_dgate.s_addr != 0) {
453 gateip = vp->v_dgate;
454 }
455 }
456 #endif
457
458 #ifdef DHCP_ENV
459 /*
460 * Parse DHCP options and store them into kenv variables.
461 * Original code from Danny Braniss, modifications by Luigi Rizzo.
462 *
463 * The parser is driven by tables which specify the type and name of
464 * each dhcp option and how it appears in kenv.
465 * The first entry in the list contains the prefix used to set the kenv
466 * name (including the . if needed), the last entry must have a 0 tag.
467 * Entries do not need to be sorted though it helps for readability.
468 *
469 * Certain vendor-specific tables can be enabled according to DHCP_ENV.
470 * Set it to 0 if you don't want any.
471 */
472 enum opt_fmt { __NONE = 0,
473 __8 = 1, __16 = 2, __32 = 4, /* Unsigned fields, value=size */
474 __IP, /* IPv4 address */
475 __TXT, /* C string */
476 __BYTES, /* byte sequence, printed %02x */
477 __INDIR, /* name=value */
478 __ILIST, /* name=value;name=value ... */
479 __VE, /* vendor specific, recurse */
480 };
481
482 struct dhcp_opt {
483 uint8_t tag;
484 uint8_t fmt;
485 const char *desc;
486 };
487
488 static struct dhcp_opt vndr_opt[] = { /* Vendor Specific Options */
489 #if DHCP_ENV == DHCP_ENV_FREEBSD /* FreeBSD table in the original code */
490 {0, 0, "FreeBSD"}, /* prefix */
491 {1, __TXT, "kernel"},
492 {2, __TXT, "kernelname"},
493 {3, __TXT, "kernel_options"},
494 {4, __IP, "usr-ip"},
495 {5, __TXT, "conf-path"},
496 {6, __TXT, "rc.conf0"},
497 {7, __TXT, "rc.conf1"},
498 {8, __TXT, "rc.conf2"},
499 {9, __TXT, "rc.conf3"},
500 {10, __TXT, "rc.conf4"},
501 {11, __TXT, "rc.conf5"},
502 {12, __TXT, "rc.conf6"},
503 {13, __TXT, "rc.conf7"},
504 {14, __TXT, "rc.conf8"},
505 {15, __TXT, "rc.conf9"},
506
507 {20, __TXT, "boot.nfsroot.options"},
508
509 {245, __INDIR, ""},
510 {246, __INDIR, ""},
511 {247, __INDIR, ""},
512 {248, __INDIR, ""},
513 {249, __INDIR, ""},
514 {250, __INDIR, ""},
515 {251, __INDIR, ""},
516 {252, __INDIR, ""},
517 {253, __INDIR, ""},
518 {254, __INDIR, ""},
519
520 #elif DHCP_ENV == DHCP_ENV_PXE /* some pxe options, RFC4578 */
521 {0, 0, "pxe"}, /* prefix */
522 {93, __16, "system-architecture"},
523 {94, __BYTES, "network-interface"},
524 {97, __BYTES, "machine-identifier"},
525 #else /* default (empty) table */
526 {0, 0, "dhcp.vendor."}, /* prefix */
527 #endif
528 {0, __TXT, "%soption-%d"}
529 };
530
531 static struct dhcp_opt dhcp_opt[] = {
532 /* DHCP Option names, formats and codes, from RFC2132. */
533 {0, 0, "dhcp."}, // prefix
534 {1, __IP, "subnet-mask"},
535 {2, __32, "time-offset"}, /* this is signed */
536 {3, __IP, "routers"},
537 {4, __IP, "time-servers"},
538 {5, __IP, "ien116-name-servers"},
539 {6, __IP, "domain-name-servers"},
540 {7, __IP, "log-servers"},
541 {8, __IP, "cookie-servers"},
542 {9, __IP, "lpr-servers"},
543 {10, __IP, "impress-servers"},
544 {11, __IP, "resource-location-servers"},
545 {12, __TXT, "host-name"},
546 {13, __16, "boot-size"},
547 {14, __TXT, "merit-dump"},
548 {15, __TXT, "domain-name"},
549 {16, __IP, "swap-server"},
550 {17, __TXT, "root-path"},
551 {18, __TXT, "extensions-path"},
552 {19, __8, "ip-forwarding"},
553 {20, __8, "non-local-source-routing"},
554 {21, __IP, "policy-filter"},
555 {22, __16, "max-dgram-reassembly"},
556 {23, __8, "default-ip-ttl"},
557 {24, __32, "path-mtu-aging-timeout"},
558 {25, __16, "path-mtu-plateau-table"},
559 {26, __16, "interface-mtu"},
560 {27, __8, "all-subnets-local"},
561 {28, __IP, "broadcast-address"},
562 {29, __8, "perform-mask-discovery"},
563 {30, __8, "mask-supplier"},
564 {31, __8, "perform-router-discovery"},
565 {32, __IP, "router-solicitation-address"},
566 {33, __IP, "static-routes"},
567 {34, __8, "trailer-encapsulation"},
568 {35, __32, "arp-cache-timeout"},
569 {36, __8, "ieee802-3-encapsulation"},
570 {37, __8, "default-tcp-ttl"},
571 {38, __32, "tcp-keepalive-interval"},
572 {39, __8, "tcp-keepalive-garbage"},
573 {40, __TXT, "nis-domain"},
574 {41, __IP, "nis-servers"},
575 {42, __IP, "ntp-servers"},
576 {43, __VE, "vendor-encapsulated-options"},
577 {44, __IP, "netbios-name-servers"},
578 {45, __IP, "netbios-dd-server"},
579 {46, __8, "netbios-node-type"},
580 {47, __TXT, "netbios-scope"},
581 {48, __IP, "x-font-servers"},
582 {49, __IP, "x-display-managers"},
583 {50, __IP, "dhcp-requested-address"},
584 {51, __32, "dhcp-lease-time"},
585 {52, __8, "dhcp-option-overload"},
586 {53, __8, "dhcp-message-type"},
587 {54, __IP, "dhcp-server-identifier"},
588 {55, __8, "dhcp-parameter-request-list"},
589 {56, __TXT, "dhcp-message"},
590 {57, __16, "dhcp-max-message-size"},
591 {58, __32, "dhcp-renewal-time"},
592 {59, __32, "dhcp-rebinding-time"},
593 {60, __TXT, "vendor-class-identifier"},
594 {61, __TXT, "dhcp-client-identifier"},
595 {64, __TXT, "nisplus-domain"},
596 {65, __IP, "nisplus-servers"},
597 {66, __TXT, "tftp-server-name"},
598 {67, __TXT, "bootfile-name"},
599 {68, __IP, "mobile-ip-home-agent"},
600 {69, __IP, "smtp-server"},
601 {70, __IP, "pop-server"},
602 {71, __IP, "nntp-server"},
603 {72, __IP, "www-server"},
604 {73, __IP, "finger-server"},
605 {74, __IP, "irc-server"},
606 {75, __IP, "streettalk-server"},
607 {76, __IP, "streettalk-directory-assistance-server"},
608 {77, __TXT, "user-class"},
609 {85, __IP, "nds-servers"},
610 {86, __TXT, "nds-tree-name"},
611 {87, __TXT, "nds-context"},
612 {210, __TXT, "authenticate"},
613
614 /* use the following entries for arbitrary variables */
615 {246, __ILIST, ""},
616 {247, __ILIST, ""},
617 {248, __ILIST, ""},
618 {249, __ILIST, ""},
619 {250, __INDIR, ""},
620 {251, __INDIR, ""},
621 {252, __INDIR, ""},
622 {253, __INDIR, ""},
623 {254, __INDIR, ""},
624 {0, __TXT, "%soption-%d"}
625 };
626
627 /*
628 * parse a dhcp response, set environment variables translating options
629 * names and values according to the tables above. Also set dhcp.tags
630 * to the list of selected tags.
631 */
632 static void
setenv_(uchar_t * cp,uchar_t * ep,struct dhcp_opt * opts)633 setenv_(uchar_t *cp, uchar_t *ep, struct dhcp_opt *opts)
634 {
635 uchar_t *ncp;
636 uchar_t tag;
637 char tags[512], *tp; /* the list of tags */
638
639 #define FLD_SEP ',' /* separator in list of elements */
640 ncp = cp;
641 tp = tags;
642 if (opts == NULL)
643 opts = dhcp_opt;
644
645 while (ncp < ep) {
646 unsigned int size; /* option size */
647 char *vp, *endv, buf[256]; /* the value buffer */
648 struct dhcp_opt *op;
649
650 tag = *ncp++; /* extract tag and size */
651 size = *ncp++;
652 cp = ncp; /* current payload */
653 ncp += size; /* point to the next option */
654
655 if (tag == TAG_END)
656 break;
657 if (tag == 0)
658 continue;
659
660 for (op = opts+1; op->tag && op->tag != tag; op++)
661 ;
662 /* if not found we end up on the default entry */
663
664 /*
665 * Copy data into the buffer. libstand does not have snprintf
666 * so we need to be careful with sprintf(). With strings, the
667 * source is always <256 char so shorter than the buffer so we
668 * are safe; with other arguments, the longest string is
669 * inet_ntoa which is 16 bytes so we make sure to have always
670 * enough room in the string before trying an sprint.
671 */
672 vp = buf;
673 *vp = '\0';
674 /* last valid write position */
675 endv = buf + sizeof (buf) - 1 - 16;
676
677 switch (op->fmt) {
678 case __NONE:
679 break; /* should not happen */
680
681 case __VE: /* recurse, vendor specific */
682 setenv_(cp, cp+size, vndr_opt);
683 break;
684
685 case __IP: /* ip address */
686 for (; size > 0 && vp < endv; size -= 4, cp += 4) {
687 struct in_addr in_ip; /* ip addresses */
688 if (vp != buf)
689 *vp++ = FLD_SEP;
690 bcopy(cp, &in_ip.s_addr, sizeof (in_ip.s_addr));
691 sprintf(vp, "%s", inet_ntoa(in_ip));
692 vp += strlen(vp);
693 }
694 break;
695
696 case __BYTES: /* opaque byte string */
697 for (; size > 0 && vp < endv; size -= 1, cp += 1) {
698 sprintf(vp, "%02x", *cp);
699 vp += strlen(vp);
700 }
701 break;
702
703 case __TXT:
704 bcopy(cp, buf, size); /* cannot overflow */
705 buf[size] = 0;
706 break;
707
708 case __32:
709 case __16:
710 case __8: /* op->fmt is also the length of each field */
711 for (; size > 0 && vp < endv;
712 size -= op->fmt, cp += op->fmt) {
713 uint32_t v;
714 if (op->fmt == __32)
715 v = (cp[0]<<24) + (cp[1]<<16) +
716 (cp[2]<<8) + cp[3];
717 else if (op->fmt == __16)
718 v = (cp[0]<<8) + cp[1];
719 else
720 v = cp[0];
721 if (vp != buf)
722 *vp++ = FLD_SEP;
723 sprintf(vp, "%u", v);
724 vp += strlen(vp);
725 }
726 break;
727
728 case __INDIR: /* name=value */
729 case __ILIST: /* name=value;name=value... */
730 bcopy(cp, buf, size); /* cannot overflow */
731 buf[size] = '\0';
732 for (endv = buf; endv; endv = vp) {
733 char *s = NULL; /* semicolon ? */
734
735 /* skip leading whitespace */
736 while (*endv && strchr(" \t\n\r", *endv))
737 endv++;
738 /* find name=value separator */
739 vp = strchr(endv, '=');
740 if (!vp)
741 break;
742 *vp++ = 0;
743 if (op->fmt == __ILIST && (s = strchr(vp, ';')))
744 *s++ = '\0';
745 setenv(endv, vp, 1);
746 vp = s; /* prepare for next round */
747 }
748 buf[0] = '\0'; /* option already done */
749 }
750
751 if (tp - tags < sizeof (tags) - 5) {
752 /* add tag to the list */
753 if (tp != tags)
754 *tp++ = FLD_SEP;
755 sprintf(tp, "%d", tag);
756 tp += strlen(tp);
757 }
758 if (buf[0]) {
759 char env[128]; /* the string name */
760
761 if (op->tag == 0)
762 sprintf(env, op->desc, opts[0].desc, tag);
763 else
764 sprintf(env, "%s%s", opts[0].desc, op->desc);
765 /*
766 * Do not replace existing values in the environment,
767 * so that locally-obtained values can override
768 * server-provided values.
769 */
770 setenv(env, buf, 0);
771 }
772 }
773 if (tp != tags) {
774 char env[128]; /* the string name */
775 sprintf(env, "%stags", opts[0].desc);
776 setenv(env, tags, 1);
777 }
778 }
779 #endif /* additional dhcp */
780