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>
65 static int tftp_open(const char *path, struct open_file *f);
66 static int tftp_close(struct open_file *f);
67 static int tftp_parse_oack(struct tftp_handle *h, char *buf, size_t len);
68 static int tftp_read(struct open_file *f, void *buf, size_t size, size_t *resid);
69 static int tftp_write(struct open_file *f, void *buf, size_t size, size_t *resid);
70 static off_t tftp_seek(struct open_file *f, off_t offset, int where);
71 static int tftp_set_blksize(struct tftp_handle *h, const char *str);
72 static int tftp_stat(struct open_file *f, struct stat *sb);
73 static ssize_t sendrecv_tftp(struct tftp_handle *h,
74 ssize_t (*sproc)(struct iodesc *, void *, size_t),
75 void *sbuf, size_t ssize,
76 ssize_t (*rproc)(struct tftp_handle *h, void **, void **, time_t, unsigned short *),
77 void **, void **, unsigned short *rtype);
79 struct fs_ops tftp_fsops = {
90 extern struct in_addr servip;
92 static int tftpport = 2000;
93 static int is_open = 0;
96 * The legacy TFTP_BLKSIZE value was SEGSIZE(512).
97 * TFTP_REQUESTED_BLKSIZE of 1428 is (Ethernet MTU, less the TFTP, UDP and
100 #define TFTP_REQUESTED_BLKSIZE 1428
103 * Choose a blksize big enough so we can test with Ethernet
104 * Jumbo frames in the future.
106 #define TFTP_MAX_BLKSIZE 9008
109 struct iodesc *iodesc;
110 int currblock; /* contents of lastdata */
111 int islastblock; /* flag */
114 char *path; /* saved for re-requests */
115 unsigned int tftp_blksize;
116 unsigned long tftp_tsize;
118 struct tftphdr *tftp_hdr;
121 #define TFTP_MAX_ERRCODE EOPTNEG
122 static const int tftperrors[TFTP_MAX_ERRCODE + 1] = {
131 EINVAL, /* Option negotiation failed. */
134 static int tftp_getnextblock(struct tftp_handle *h);
136 /* send error message back. */
138 tftp_senderr(struct tftp_handle *h, u_short errcode, const char *msg)
141 u_char header[HEADER_SIZE];
143 u_char space[63]; /* +1 from t */
144 } __packed __aligned(4) wbuf;
149 if (len > sizeof(wbuf.space))
150 len = sizeof(wbuf.space);
152 wbuf.t.th_opcode = htons((u_short) ERROR);
153 wbuf.t.th_code = htons(errcode);
155 wtail = wbuf.t.th_msg;
156 bcopy(msg, wtail, len);
160 sendudp(h->iodesc, &wbuf.t, wtail - (char *) &wbuf.t);
164 tftp_sendack(struct tftp_handle *h)
167 u_char header[HEADER_SIZE];
169 } __packed __aligned(4) wbuf;
172 wbuf.t.th_opcode = htons((u_short) ACK);
173 wtail = (char *) &wbuf.t.th_block;
174 wbuf.t.th_block = htons((u_short) h->currblock);
177 sendudp(h->iodesc, &wbuf.t, wtail - (char *) &wbuf.t);
181 recvtftp(struct tftp_handle *h, void **pkt, void **payload, time_t tleft,
182 unsigned short *rtype)
184 struct iodesc *d = h->iodesc;
191 len = readudp(d, &ptr, (void **)&t, tleft);
198 *rtype = ntohs(t->th_opcode);
199 switch (ntohs(t->th_opcode)) {
203 if (htons(t->th_block) != (u_short) d->xid) {
212 * First data packet from new port.
215 uh = (struct udphdr *) t - 1;
216 d->destport = uh->uh_sport;
217 } /* else check uh_sport has not changed??? */
218 got = len - (t->th_data - (char *)t);
224 if ((unsigned) ntohs(t->th_code) > TFTP_MAX_ERRCODE) {
225 printf("illegal tftp error %d\n", ntohs(t->th_code));
229 printf("tftp-error %d\n", ntohs(t->th_code));
231 errno = tftperrors[ntohs(t->th_code)];
240 * Unexpected OACK. TFTP transfer already in progress.
249 * Remember which port this OACK came from, because we need
250 * to send the ACK or errors back to it.
252 uh = (struct udphdr *) t - 1;
253 d->destport = uh->uh_sport;
255 /* Parse options ACK-ed by the server. */
256 tftp_oack_len = len - sizeof(t->th_opcode);
257 if (tftp_parse_oack(h, t->th_u.tu_stuff, tftp_oack_len) != 0) {
258 tftp_senderr(h, EOPTNEG, "Malformed OACK");
269 printf("tftp type %d not handled\n", ntohs(t->th_opcode));
276 /* send request, expect first block (or error) */
278 tftp_makereq(struct tftp_handle *h)
281 u_char header[HEADER_SIZE];
283 u_char space[FNAME_SIZE + 6];
284 } __packed __aligned(4) wbuf;
290 char *tftp_blksize = NULL;
292 unsigned short rtype = 0;
295 * Allow overriding default TFTP block size by setting
296 * a tftp.blksize environment variable.
298 if ((tftp_blksize = getenv("tftp.blksize")) != NULL) {
299 tftp_set_blksize(h, tftp_blksize);
302 wbuf.t.th_opcode = htons((u_short) RRQ);
303 wtail = wbuf.t.th_stuff;
305 #ifdef TFTP_PREPEND_PATH
306 if (l > FNAME_SIZE - (sizeof(TFTP_PREPEND_PATH) - 1))
307 return (ENAMETOOLONG);
308 bcopy(TFTP_PREPEND_PATH, wtail, sizeof(TFTP_PREPEND_PATH) - 1);
309 wtail += sizeof(TFTP_PREPEND_PATH) - 1;
312 return (ENAMETOOLONG);
314 bcopy(h->path, wtail, l + 1);
316 bcopy("octet", wtail, 6);
318 bcopy("blksize", wtail, 8);
320 blksize_l = sprintf(wtail, "%d", h->tftp_blksize);
321 wtail += blksize_l + 1;
322 bcopy("tsize", wtail, 6);
324 bcopy("0", wtail, 2);
327 /* h->iodesc->myport = htons(--tftpport); */
328 h->iodesc->myport = htons(tftpport + (getsecs() & 0x3ff));
329 h->iodesc->destport = htons(IPPORT_TFTP);
330 h->iodesc->xid = 1; /* expected block */
337 res = sendrecv_tftp(h, &sendudp, &wbuf.t, wtail - (char *) &wbuf.t,
338 &recvtftp, &pkt, (void **)&t, &rtype);
349 return (tftp_getnextblock(h));
351 /* Server ignored our blksize request, revert to TFTP default. */
352 h->tftp_blksize = SEGSIZE;
359 if (res < h->tftp_blksize) {
360 h->islastblock = 1; /* very short file */
372 /* ack block, expect next */
374 tftp_getnextblock(struct tftp_handle *h)
377 u_char header[HEADER_SIZE];
379 } __packed __aligned(4) wbuf;
384 unsigned short rtype = 0;
385 wbuf.t.th_opcode = htons((u_short) ACK);
386 wtail = (char *) &wbuf.t.th_block;
387 wbuf.t.th_block = htons((u_short) h->currblock);
390 h->iodesc->xid = h->currblock + 1; /* expected block */
393 res = sendrecv_tftp(h, &sendudp, &wbuf.t, wtail - (char *) &wbuf.t,
394 &recvtftp, &pkt, (void **)&t, &rtype);
396 if (res == -1) { /* 0 is OK! */
406 if (res < h->tftp_blksize)
407 h->islastblock = 1; /* EOF */
409 if (h->islastblock == 1) {
410 /* Send an ACK for the last block */
411 wbuf.t.th_block = htons((u_short) h->currblock);
412 sendudp(h->iodesc, &wbuf.t, wtail - (char *)&wbuf.t);
419 tftp_open(const char *path, struct open_file *f)
421 struct tftp_handle *tftpfile;
425 const char *extraslash;
427 if (netproto != NET_TFTP)
430 if (f->f_dev->dv_type != DEVT_NET)
436 tftpfile = (struct tftp_handle *) malloc(sizeof(*tftpfile));
440 memset(tftpfile, 0, sizeof(*tftpfile));
441 tftpfile->tftp_blksize = TFTP_REQUESTED_BLKSIZE;
442 tftpfile->iodesc = io = socktodesc(*(int *) (f->f_devdata));
448 pathsize = (strlen(rootpath) + 1 + strlen(path) + 1) * sizeof(char);
449 tftpfile->path = malloc(pathsize);
450 if (tftpfile->path == NULL) {
454 if (rootpath[strlen(rootpath) - 1] == '/' || path[0] == '/')
458 res = snprintf(tftpfile->path, pathsize, "%s%s%s",
459 rootpath, extraslash, path);
460 if (res < 0 || res > pathsize) {
461 free(tftpfile->path);
466 res = tftp_makereq(tftpfile);
469 free(tftpfile->path);
473 f->f_fsdata = (void *) tftpfile;
479 tftp_read(struct open_file *f, void *addr, size_t size,
480 size_t *resid /* out */)
482 struct tftp_handle *tftpfile;
483 tftpfile = (struct tftp_handle *) f->f_fsdata;
486 int needblock, count;
490 needblock = tftpfile->off / tftpfile->tftp_blksize + 1;
492 if (tftpfile->currblock > needblock) { /* seek backwards */
493 tftp_senderr(tftpfile, 0, "No error: read aborted");
494 tftp_makereq(tftpfile); /* no error check, it worked
498 while (tftpfile->currblock < needblock) {
501 res = tftp_getnextblock(tftpfile);
502 if (res) { /* no answer */
504 printf("tftp: read error\n");
508 if (tftpfile->islastblock)
512 if (tftpfile->currblock == needblock) {
513 int offinblock, inbuffer;
515 offinblock = tftpfile->off % tftpfile->tftp_blksize;
517 inbuffer = tftpfile->validsize - offinblock;
520 printf("tftp: invalid offset %d\n",
525 count = (size < inbuffer ? size : inbuffer);
526 bcopy(tftpfile->tftp_hdr->th_data + offinblock,
529 addr = (char *)addr + count;
530 tftpfile->off += count;
533 if ((tftpfile->islastblock) && (count == inbuffer))
537 printf("tftp: block %d not found\n", needblock);
550 tftp_close(struct open_file *f)
552 struct tftp_handle *tftpfile;
553 tftpfile = (struct tftp_handle *) f->f_fsdata;
555 /* let it time out ... */
558 free(tftpfile->path);
567 tftp_write(struct open_file *f __unused, void *start __unused, size_t size __unused,
568 size_t *resid __unused /* out */)
574 tftp_stat(struct open_file *f, struct stat *sb)
576 struct tftp_handle *tftpfile;
577 tftpfile = (struct tftp_handle *) f->f_fsdata;
579 sb->st_mode = 0444 | S_IFREG;
583 sb->st_size = (off_t) tftpfile->tftp_tsize;
588 tftp_seek(struct open_file *f, off_t offset, int where)
590 struct tftp_handle *tftpfile;
591 tftpfile = (struct tftp_handle *) f->f_fsdata;
595 tftpfile->off = offset;
598 tftpfile->off += offset;
604 return (tftpfile->off);
608 sendrecv_tftp(struct tftp_handle *h,
609 ssize_t (*sproc)(struct iodesc *, void *, size_t),
610 void *sbuf, size_t ssize,
611 ssize_t (*rproc)(struct tftp_handle *, void **, void **, time_t,
613 void **pkt, void **payload, unsigned short *rtype)
615 struct iodesc *d = h->iodesc;
621 printf("sendrecv: called\n");
627 if ((getsecs() - t) > MAXTMO) {
632 cc = (*sproc)(d, sbuf, ssize);
633 if (cc != -1 && cc < ssize)
634 panic("sendrecv: short write! (%zd < %zu)",
638 /* Error on transmit; wait before retrying */
639 while ((getsecs() - t1) < tleft);
644 /* Try to get a packet and process it. */
645 cc = (*rproc)(h, pkt, payload, tleft, rtype);
646 /* Return on data, EOF or real error. */
647 if (cc != -1 || errno != 0)
649 if ((getsecs() - t1) < tleft) {
653 /* Timed out or didn't get the packet we're waiting for */
655 if (tleft > (2 * MINTMO)) {
656 tleft = (2 * MINTMO);
663 tftp_set_blksize(struct tftp_handle *h, const char *str)
669 if (h == NULL || str == NULL)
673 (unsigned int)strtol(str, &endptr, 0);
676 * Only accept blksize value if it is numeric.
677 * RFC2348 specifies that acceptable values are 8-65464.
678 * Let's choose a limit less than MAXRSPACE.
680 if (*endptr == '\0' && new_blksize >= 8
681 && new_blksize <= TFTP_MAX_BLKSIZE) {
682 h->tftp_blksize = new_blksize;
690 * In RFC2347, the TFTP Option Acknowledgement package (OACK)
691 * is used to acknowledge a client's option negotiation request.
692 * The format of an OACK packet is:
693 * +-------+---~~---+---+---~~---+---+---~~---+---+---~~---+---+
694 * | opc | opt1 | 0 | value1 | 0 | optN | 0 | valueN | 0 |
695 * +-------+---~~---+---+---~~---+---+---~~---+---+---~~---+---+
698 * The opcode field contains a 6, for Option Acknowledgment.
701 * The first option acknowledgment, copied from the original
705 * The acknowledged value associated with the first option. If
706 * and how this value may differ from the original request is
707 * detailed in the specification for the option.
710 * The final option/value acknowledgment pair.
713 tftp_parse_oack(struct tftp_handle *h, char *buf, size_t len)
716 * We parse the OACK strings into an array
717 * of name-value pairs.
719 char *tftp_options[128] = { 0 };
723 int blksize_is_set = 0;
726 unsigned int orig_blksize;
728 while (option_idx < 128 && i < len) {
729 if (buf[i] == '\0') {
731 tftp_options[option_idx] = val;
739 /* Save the block size we requested for sanity check later. */
740 orig_blksize = h->tftp_blksize;
743 * Parse individual TFTP options.
744 * * "blksize" is specified in RFC2348.
745 * * "tsize" is specified in RFC2349.
747 for (i = 0; i < option_idx; i += 2) {
748 if (strcasecmp(tftp_options[i], "blksize") == 0) {
749 if (i + 1 < option_idx)
751 tftp_set_blksize(h, tftp_options[i + 1]);
752 } else if (strcasecmp(tftp_options[i], "tsize") == 0) {
753 if (i + 1 < option_idx)
754 tsize = strtol(tftp_options[i + 1], (char **)NULL, 10);
756 h->tftp_tsize = tsize;
758 /* Do not allow any options we did not expect to be ACKed. */
759 printf("unexpected tftp option '%s'\n", tftp_options[i]);
764 if (!blksize_is_set) {
766 * If TFTP blksize was not set, try defaulting
767 * to the legacy TFTP blksize of SEGSIZE(512)
769 h->tftp_blksize = SEGSIZE;
770 } else if (h->tftp_blksize > orig_blksize) {
772 * Server should not be proposing block sizes that
773 * exceed what we said we can handle.
775 printf("unexpected blksize %u\n", h->tftp_blksize);
780 printf("tftp_blksize: %u\n", h->tftp_blksize);
781 printf("tftp_tsize: %lu\n", h->tftp_tsize);