1 /* $NetBSD: tftp.c,v 1.4 1997/09/17 16:57:07 drochner Exp $ */
5 * Matthias Drochner. All rights reserved.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed for the NetBSD Project
18 * by Matthias Drochner.
19 * 4. The name of the author may not be used to endorse or promote products
20 * derived from this software without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
38 * Simple TFTP implementation for libsa.
40 * - socket descriptor (int) at open_file->f_devdata
41 * - server host IP in global servip
44 * - lseek only with SEEK_SET or SEEK_CUR
45 * - no big time differences between transfers (<tftp timeout)
48 #include <sys/types.h>
50 #include <netinet/in.h>
51 #include <netinet/udp.h>
52 #include <netinet/in_systm.h>
53 #include <arpa/tftp.h>
64 struct tftprecv_extra;
66 static ssize_t recvtftp(struct iodesc *d, void **pkt, void **payload,
67 time_t tleft, void *recv_extra);
68 static int tftp_open(const char *path, struct open_file *f);
69 static int tftp_close(struct open_file *f);
70 static int tftp_parse_oack(struct tftp_handle *h, char *buf, size_t len);
71 static int tftp_read(struct open_file *f, void *buf, size_t size, size_t *resid);
72 static off_t tftp_seek(struct open_file *f, off_t offset, int where);
73 static int tftp_set_blksize(struct tftp_handle *h, const char *str);
74 static int tftp_stat(struct open_file *f, struct stat *sb);
76 struct fs_ops tftp_fsops = {
87 extern struct in_addr servip;
89 static int tftpport = 2000;
90 static int is_open = 0;
93 * The legacy TFTP_BLKSIZE value was SEGSIZE(512).
94 * TFTP_REQUESTED_BLKSIZE of 1428 is (Ethernet MTU, less the TFTP, UDP and
97 #define TFTP_REQUESTED_BLKSIZE 1428
100 * Choose a blksize big enough so we can test with Ethernet
101 * Jumbo frames in the future.
103 #define TFTP_MAX_BLKSIZE 9008
106 struct iodesc *iodesc;
107 int currblock; /* contents of lastdata */
108 int islastblock; /* flag */
111 char *path; /* saved for re-requests */
112 unsigned int tftp_blksize;
113 unsigned long tftp_tsize;
115 struct tftphdr *tftp_hdr;
118 struct tftprecv_extra {
119 struct tftp_handle *tftp_handle;
120 unsigned short rtype; /* Received type */
123 #define TFTP_MAX_ERRCODE EOPTNEG
124 static const int tftperrors[TFTP_MAX_ERRCODE + 1] = {
133 EINVAL, /* Option negotiation failed. */
136 static int tftp_getnextblock(struct tftp_handle *h);
138 /* send error message back. */
140 tftp_senderr(struct tftp_handle *h, u_short errcode, const char *msg)
143 u_char header[HEADER_SIZE];
145 u_char space[63]; /* +1 from t */
146 } __packed __aligned(4) wbuf;
151 if (len > sizeof(wbuf.space))
152 len = sizeof(wbuf.space);
154 wbuf.t.th_opcode = htons((u_short) ERROR);
155 wbuf.t.th_code = htons(errcode);
157 wtail = wbuf.t.th_msg;
158 bcopy(msg, wtail, len);
162 sendudp(h->iodesc, &wbuf.t, wtail - (char *) &wbuf.t);
166 tftp_sendack(struct tftp_handle *h)
169 u_char header[HEADER_SIZE];
171 } __packed __aligned(4) wbuf;
174 wbuf.t.th_opcode = htons((u_short) ACK);
175 wtail = (char *) &wbuf.t.th_block;
176 wbuf.t.th_block = htons((u_short) h->currblock);
179 sendudp(h->iodesc, &wbuf.t, wtail - (char *) &wbuf.t);
183 recvtftp(struct iodesc *d, void **pkt, void **payload, time_t tleft,
186 struct tftprecv_extra *extra;
187 struct tftp_handle *h;
189 unsigned short *rtype;
194 extra = (struct tftprecv_extra *)recv_extra;
195 h = extra->tftp_handle;
197 len = readudp(d, &ptr, (void **)&t, tleft);
204 extra->rtype = ntohs(t->th_opcode);
205 switch (ntohs(t->th_opcode)) {
209 if (htons(t->th_block) != (u_short) d->xid) {
218 * First data packet from new port.
221 uh = (struct udphdr *) t - 1;
222 d->destport = uh->uh_sport;
223 } /* else check uh_sport has not changed??? */
224 got = len - (t->th_data - (char *)t);
230 if ((unsigned) ntohs(t->th_code) > TFTP_MAX_ERRCODE) {
231 printf("illegal tftp error %d\n", ntohs(t->th_code));
235 printf("tftp-error %d\n", ntohs(t->th_code));
237 errno = tftperrors[ntohs(t->th_code)];
246 * Unexpected OACK. TFTP transfer already in progress.
255 * Remember which port this OACK came from, because we need
256 * to send the ACK or errors back to it.
258 uh = (struct udphdr *) t - 1;
259 d->destport = uh->uh_sport;
261 /* Parse options ACK-ed by the server. */
262 tftp_oack_len = len - sizeof(t->th_opcode);
263 if (tftp_parse_oack(h, t->th_u.tu_stuff, tftp_oack_len) != 0) {
264 tftp_senderr(h, EOPTNEG, "Malformed OACK");
275 printf("tftp type %d not handled\n", ntohs(t->th_opcode));
282 /* send request, expect first block (or error) */
284 tftp_makereq(struct tftp_handle *h)
287 u_char header[HEADER_SIZE];
289 u_char space[FNAME_SIZE + 6];
290 } __packed __aligned(4) wbuf;
291 struct tftprecv_extra recv_extra;
297 char *tftp_blksize = NULL;
301 * Allow overriding default TFTP block size by setting
302 * a tftp.blksize environment variable.
304 if ((tftp_blksize = getenv("tftp.blksize")) != NULL) {
305 tftp_set_blksize(h, tftp_blksize);
308 wbuf.t.th_opcode = htons((u_short) RRQ);
309 wtail = wbuf.t.th_stuff;
311 #ifdef TFTP_PREPEND_PATH
312 if (l > FNAME_SIZE - (sizeof(TFTP_PREPEND_PATH) - 1))
313 return (ENAMETOOLONG);
314 bcopy(TFTP_PREPEND_PATH, wtail, sizeof(TFTP_PREPEND_PATH) - 1);
315 wtail += sizeof(TFTP_PREPEND_PATH) - 1;
318 return (ENAMETOOLONG);
320 bcopy(h->path, wtail, l + 1);
322 bcopy("octet", wtail, 6);
324 bcopy("blksize", wtail, 8);
326 blksize_l = sprintf(wtail, "%d", h->tftp_blksize);
327 wtail += blksize_l + 1;
328 bcopy("tsize", wtail, 6);
330 bcopy("0", wtail, 2);
333 /* h->iodesc->myport = htons(--tftpport); */
334 h->iodesc->myport = htons(tftpport + (getsecs() & 0x3ff));
335 h->iodesc->destport = htons(IPPORT_TFTP);
336 h->iodesc->xid = 1; /* expected block */
343 recv_extra.tftp_handle = h;
344 res = sendrecv(h->iodesc, &sendudp, &wbuf.t, wtail - (char *) &wbuf.t,
345 (void *)&recvtftp, &pkt, (void **)&t, &recv_extra);
355 if (recv_extra.rtype == OACK)
356 return (tftp_getnextblock(h));
358 /* Server ignored our blksize request, revert to TFTP default. */
359 h->tftp_blksize = SEGSIZE;
361 switch (recv_extra.rtype) {
366 if (res < h->tftp_blksize) {
367 h->islastblock = 1; /* very short file */
379 /* ack block, expect next */
381 tftp_getnextblock(struct tftp_handle *h)
384 u_char header[HEADER_SIZE];
386 } __packed __aligned(4) wbuf;
387 struct tftprecv_extra recv_extra;
392 wbuf.t.th_opcode = htons((u_short) ACK);
393 wtail = (char *) &wbuf.t.th_block;
394 wbuf.t.th_block = htons((u_short) h->currblock);
397 h->iodesc->xid = h->currblock + 1; /* expected block */
400 recv_extra.tftp_handle = h;
401 res = sendrecv(h->iodesc, &sendudp, &wbuf.t, wtail - (char *) &wbuf.t,
402 (void *)&recvtftp, &pkt, (void **)&t, &recv_extra);
404 if (res == -1) { /* 0 is OK! */
414 if (res < h->tftp_blksize)
415 h->islastblock = 1; /* EOF */
417 if (h->islastblock == 1) {
418 /* Send an ACK for the last block */
419 wbuf.t.th_block = htons((u_short) h->currblock);
420 sendudp(h->iodesc, &wbuf.t, wtail - (char *)&wbuf.t);
427 tftp_open(const char *path, struct open_file *f)
429 struct tftp_handle *tftpfile;
433 const char *extraslash;
435 if (netproto != NET_TFTP)
438 if (f->f_dev->dv_type != DEVT_NET)
444 tftpfile = (struct tftp_handle *) malloc(sizeof(*tftpfile));
448 memset(tftpfile, 0, sizeof(*tftpfile));
449 tftpfile->tftp_blksize = TFTP_REQUESTED_BLKSIZE;
450 tftpfile->iodesc = io = socktodesc(*(int *) (f->f_devdata));
456 pathsize = (strlen(rootpath) + 1 + strlen(path) + 1) * sizeof(char);
457 tftpfile->path = malloc(pathsize);
458 if (tftpfile->path == NULL) {
462 if (rootpath[strlen(rootpath) - 1] == '/' || path[0] == '/')
466 res = snprintf(tftpfile->path, pathsize, "%s%s%s",
467 rootpath, extraslash, path);
468 if (res < 0 || res > pathsize) {
469 free(tftpfile->path);
474 res = tftp_makereq(tftpfile);
477 free(tftpfile->path);
482 f->f_fsdata = (void *) tftpfile;
488 tftp_read(struct open_file *f, void *addr, size_t size,
489 size_t *resid /* out */)
491 struct tftp_handle *tftpfile;
492 tftpfile = (struct tftp_handle *) f->f_fsdata;
495 int needblock, count;
499 needblock = tftpfile->off / tftpfile->tftp_blksize + 1;
501 if (tftpfile->currblock > needblock) { /* seek backwards */
502 tftp_senderr(tftpfile, 0, "No error: read aborted");
503 tftp_makereq(tftpfile); /* no error check, it worked
507 while (tftpfile->currblock < needblock) {
510 res = tftp_getnextblock(tftpfile);
511 if (res) { /* no answer */
513 printf("tftp: read error\n");
517 if (tftpfile->islastblock)
521 if (tftpfile->currblock == needblock) {
522 int offinblock, inbuffer;
524 offinblock = tftpfile->off % tftpfile->tftp_blksize;
526 inbuffer = tftpfile->validsize - offinblock;
529 printf("tftp: invalid offset %d\n",
534 count = (size < inbuffer ? size : inbuffer);
535 bcopy(tftpfile->tftp_hdr->th_data + offinblock,
538 addr = (char *)addr + count;
539 tftpfile->off += count;
542 if ((tftpfile->islastblock) && (count == inbuffer))
546 printf("tftp: block %d not found\n", needblock);
559 tftp_close(struct open_file *f)
561 struct tftp_handle *tftpfile;
562 tftpfile = (struct tftp_handle *) f->f_fsdata;
564 /* let it time out ... */
567 free(tftpfile->path);
576 tftp_stat(struct open_file *f, struct stat *sb)
578 struct tftp_handle *tftpfile;
579 tftpfile = (struct tftp_handle *) f->f_fsdata;
581 sb->st_mode = 0444 | S_IFREG;
585 sb->st_size = (off_t) tftpfile->tftp_tsize;
590 tftp_seek(struct open_file *f, off_t offset, int where)
592 struct tftp_handle *tftpfile;
593 tftpfile = (struct tftp_handle *) f->f_fsdata;
597 tftpfile->off = offset;
600 tftpfile->off += offset;
606 return (tftpfile->off);
610 tftp_set_blksize(struct tftp_handle *h, const char *str)
616 if (h == NULL || str == NULL)
620 (unsigned int)strtol(str, &endptr, 0);
623 * Only accept blksize value if it is numeric.
624 * RFC2348 specifies that acceptable values are 8-65464.
625 * Let's choose a limit less than MAXRSPACE.
627 if (*endptr == '\0' && new_blksize >= 8
628 && new_blksize <= TFTP_MAX_BLKSIZE) {
629 h->tftp_blksize = new_blksize;
637 * In RFC2347, the TFTP Option Acknowledgement package (OACK)
638 * is used to acknowledge a client's option negotiation request.
639 * The format of an OACK packet is:
640 * +-------+---~~---+---+---~~---+---+---~~---+---+---~~---+---+
641 * | opc | opt1 | 0 | value1 | 0 | optN | 0 | valueN | 0 |
642 * +-------+---~~---+---+---~~---+---+---~~---+---+---~~---+---+
645 * The opcode field contains a 6, for Option Acknowledgment.
648 * The first option acknowledgment, copied from the original
652 * The acknowledged value associated with the first option. If
653 * and how this value may differ from the original request is
654 * detailed in the specification for the option.
657 * The final option/value acknowledgment pair.
660 tftp_parse_oack(struct tftp_handle *h, char *buf, size_t len)
663 * We parse the OACK strings into an array
664 * of name-value pairs.
666 char *tftp_options[128] = { 0 };
670 int blksize_is_set = 0;
673 unsigned int orig_blksize;
675 while (option_idx < 128 && i < len) {
676 if (buf[i] == '\0') {
678 tftp_options[option_idx] = val;
686 /* Save the block size we requested for sanity check later. */
687 orig_blksize = h->tftp_blksize;
690 * Parse individual TFTP options.
691 * * "blksize" is specified in RFC2348.
692 * * "tsize" is specified in RFC2349.
694 for (i = 0; i < option_idx; i += 2) {
695 if (strcasecmp(tftp_options[i], "blksize") == 0) {
696 if (i + 1 < option_idx)
698 tftp_set_blksize(h, tftp_options[i + 1]);
699 } else if (strcasecmp(tftp_options[i], "tsize") == 0) {
700 if (i + 1 < option_idx)
701 tsize = strtol(tftp_options[i + 1], (char **)NULL, 10);
703 h->tftp_tsize = tsize;
705 /* Do not allow any options we did not expect to be ACKed. */
706 printf("unexpected tftp option '%s'\n", tftp_options[i]);
711 if (!blksize_is_set) {
713 * If TFTP blksize was not set, try defaulting
714 * to the legacy TFTP blksize of SEGSIZE(512)
716 h->tftp_blksize = SEGSIZE;
717 } else if (h->tftp_blksize > orig_blksize) {
719 * Server should not be proposing block sizes that
720 * exceed what we said we can handle.
722 printf("unexpected blksize %u\n", h->tftp_blksize);
727 printf("tftp_blksize: %u\n", h->tftp_blksize);
728 printf("tftp_tsize: %lu\n", h->tftp_tsize);