Annotation of src/usr.bin/tftp/tftp.c, Revision 1.10
1.10 ! millert 1: /* $OpenBSD: tftp.c,v 1.9 2001/11/19 19:02:16 mpech Exp $ */
1.1 deraadt 2: /* $NetBSD: tftp.c,v 1.5 1995/04/29 05:55:25 cgd Exp $ */
3:
4: /*
5: * Copyright (c) 1983, 1993
6: * The Regents of the University of California. All rights reserved.
7: *
8: * Redistribution and use in source and binary forms, with or without
9: * modification, are permitted provided that the following conditions
10: * are met:
11: * 1. Redistributions of source code must retain the above copyright
12: * notice, this list of conditions and the following disclaimer.
13: * 2. Redistributions in binary form must reproduce the above copyright
14: * notice, this list of conditions and the following disclaimer in the
15: * documentation and/or other materials provided with the distribution.
16: * 3. All advertising materials mentioning features or use of this software
17: * must display the following acknowledgement:
18: * This product includes software developed by the University of
19: * California, Berkeley and its contributors.
20: * 4. Neither the name of the University nor the names of its contributors
21: * may be used to endorse or promote products derived from this software
22: * without specific prior written permission.
23: *
24: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34: * SUCH DAMAGE.
35: */
36:
37: #ifndef lint
38: #if 0
39: static char sccsid[] = "@(#)tftp.c 8.1 (Berkeley) 6/6/93";
40: #endif
1.10 ! millert 41: static char rcsid[] = "$OpenBSD: tftp.c,v 1.9 2001/11/19 19:02:16 mpech Exp $";
1.1 deraadt 42: #endif /* not lint */
43:
44: /* Many bug fixes are from Jim Guyton <guyton@rand-unix> */
45:
46: /*
47: * TFTP User Program -- Protocol Machines
48: */
49: #include <sys/types.h>
50: #include <sys/socket.h>
51: #include <sys/time.h>
52:
53: #include <netinet/in.h>
54:
55: #include <arpa/tftp.h>
56:
57: #include <errno.h>
58: #include <setjmp.h>
59: #include <signal.h>
60: #include <stdio.h>
61: #include <string.h>
62: #include <unistd.h>
1.7 mickey 63: #include <err.h>
1.1 deraadt 64:
65: #include "extern.h"
66: #include "tftpsubs.h"
67:
68:
69: extern struct sockaddr_in peeraddr; /* filled in by main */
70: extern int f; /* the opened socket */
71: extern int trace;
72: extern int verbose;
73: extern int rexmtval;
74: extern int maxtimeout;
75:
76: #define PKTSIZE SEGSIZE+4
77: char ackbuf[PKTSIZE];
78: int timeout;
79: jmp_buf toplevel;
80: jmp_buf timeoutbuf;
81:
1.10 ! millert 82: static void nak(int);
! 83: static int makerequest(int, const char *, struct tftphdr *, const char *);
! 84: static void printstats(const char *, unsigned long);
! 85: static void startclock(void);
! 86: static void stopclock(void);
! 87: static void timer(int);
! 88: static void tpacket(const char *, struct tftphdr *, int);
1.1 deraadt 89:
90: /*
91: * Send the requested file.
92: */
93: void
94: sendfile(fd, name, mode)
95: int fd;
96: char *name;
97: char *mode;
98: {
1.9 mpech 99: struct tftphdr *ap; /* data and ack packets */
1.1 deraadt 100: struct tftphdr *r_init(), *dp;
1.9 mpech 101: int n;
1.1 deraadt 102: volatile int block, size, convert;
103: volatile unsigned long amount;
104: struct sockaddr_in from;
105: int fromlen;
106: FILE *file;
107:
108: startclock(); /* start stat's clock */
109: dp = r_init(); /* reset fillbuf/read-ahead code */
110: ap = (struct tftphdr *)ackbuf;
111: file = fdopen(fd, "r");
112: convert = !strcmp(mode, "netascii");
113: block = 0;
114: amount = 0;
115:
116: signal(SIGALRM, timer);
117: do {
118: if (block == 0)
119: size = makerequest(WRQ, name, dp, mode) - 4;
120: else {
121: /* size = read(fd, dp->th_data, SEGSIZE); */
122: size = readit(file, &dp, convert);
123: if (size < 0) {
124: nak(errno + 100);
125: break;
126: }
127: dp->th_opcode = htons((u_short)DATA);
128: dp->th_block = htons((u_short)block);
129: }
130: timeout = 0;
131: (void) setjmp(timeoutbuf);
132: send_data:
133: if (trace)
134: tpacket("sent", dp, size + 4);
135: n = sendto(f, dp, size + 4, 0,
136: (struct sockaddr *)&peeraddr, sizeof(peeraddr));
137: if (n != size + 4) {
1.7 mickey 138: warn("sendto");
1.1 deraadt 139: goto abort;
140: }
141: read_ahead(file, convert);
142: for ( ; ; ) {
143: alarm(rexmtval);
144: do {
145: fromlen = sizeof(from);
146: n = recvfrom(f, ackbuf, sizeof(ackbuf), 0,
147: (struct sockaddr *)&from, &fromlen);
148: } while (n <= 0);
149: alarm(0);
150: if (n < 0) {
1.7 mickey 151: warn("recvfrom");
1.1 deraadt 152: goto abort;
153: }
154: peeraddr.sin_port = from.sin_port; /* added */
155: if (trace)
156: tpacket("received", ap, n);
157: /* should verify packet came from server */
158: ap->th_opcode = ntohs(ap->th_opcode);
159: ap->th_block = ntohs(ap->th_block);
160: if (ap->th_opcode == ERROR) {
161: printf("Error code %d: %s\n", ap->th_code,
162: ap->th_msg);
163: goto abort;
164: }
165: if (ap->th_opcode == ACK) {
166: int j;
167:
168: if (ap->th_block == block) {
169: break;
170: }
171: /* On an error, try to synchronize
172: * both sides.
173: */
174: j = synchnet(f);
175: if (j && trace) {
176: printf("discarded %d packets\n",
177: j);
178: }
179: if (ap->th_block == (block-1)) {
180: goto send_data;
181: }
182: }
183: }
184: if (block > 0)
185: amount += size;
186: block++;
187: } while (size == SEGSIZE || block == 1);
188: abort:
189: fclose(file);
190: stopclock();
191: if (amount > 0)
192: printstats("Sent", amount);
193: }
194:
195: /*
196: * Receive a file.
197: */
198: void
199: recvfile(fd, name, mode)
200: int fd;
201: char *name;
202: char *mode;
203: {
1.9 mpech 204: struct tftphdr *ap;
1.1 deraadt 205: struct tftphdr *dp, *w_init();
1.9 mpech 206: int n;
1.1 deraadt 207: volatile int block, size, firsttrip;
208: volatile unsigned long amount;
209: struct sockaddr_in from;
210: int fromlen;
211: FILE *file;
212: volatile int convert; /* true if converting crlf -> lf */
213:
214: startclock();
215: dp = w_init();
216: ap = (struct tftphdr *)ackbuf;
217: file = fdopen(fd, "w");
218: convert = !strcmp(mode, "netascii");
219: block = 1;
220: firsttrip = 1;
221: amount = 0;
222:
223: signal(SIGALRM, timer);
224: do {
225: if (firsttrip) {
226: size = makerequest(RRQ, name, ap, mode);
227: firsttrip = 0;
228: } else {
229: ap->th_opcode = htons((u_short)ACK);
230: ap->th_block = htons((u_short)(block));
231: size = 4;
232: block++;
233: }
234: timeout = 0;
235: (void) setjmp(timeoutbuf);
236: send_ack:
237: if (trace)
238: tpacket("sent", ap, size);
239: if (sendto(f, ackbuf, size, 0, (struct sockaddr *)&peeraddr,
240: sizeof(peeraddr)) != size) {
241: alarm(0);
1.7 mickey 242: warn("sendto");
1.1 deraadt 243: goto abort;
244: }
245: write_behind(file, convert);
246: for ( ; ; ) {
247: alarm(rexmtval);
248: do {
249: fromlen = sizeof(from);
250: n = recvfrom(f, dp, PKTSIZE, 0,
251: (struct sockaddr *)&from, &fromlen);
252: } while (n <= 0);
253: alarm(0);
254: if (n < 0) {
1.7 mickey 255: warn("recvfrom");
1.1 deraadt 256: goto abort;
257: }
258: peeraddr.sin_port = from.sin_port; /* added */
259: if (trace)
260: tpacket("received", dp, n);
261: /* should verify client address */
262: dp->th_opcode = ntohs(dp->th_opcode);
263: dp->th_block = ntohs(dp->th_block);
264: if (dp->th_opcode == ERROR) {
265: printf("Error code %d: %s\n", dp->th_code,
266: dp->th_msg);
267: goto abort;
268: }
269: if (dp->th_opcode == DATA) {
270: int j;
271:
272: if (dp->th_block == block) {
273: break; /* have next packet */
274: }
275: /* On an error, try to synchronize
276: * both sides.
277: */
278: j = synchnet(f);
279: if (j && trace) {
280: printf("discarded %d packets\n", j);
281: }
282: if (dp->th_block == (block-1)) {
283: goto send_ack; /* resend ack */
284: }
285: }
286: }
287: /* size = write(fd, dp->th_data, n - 4); */
288: size = writeit(file, &dp, n - 4, convert);
289: if (size < 0) {
290: nak(errno + 100);
291: break;
292: }
293: amount += size;
294: } while (size == SEGSIZE);
295: abort: /* ok to ack, since user */
296: ap->th_opcode = htons((u_short)ACK); /* has seen err msg */
297: ap->th_block = htons((u_short)block);
298: (void) sendto(f, ackbuf, 4, 0, (struct sockaddr *)&peeraddr,
299: sizeof(peeraddr));
300: write_behind(file, convert); /* flush last buffer */
301: fclose(file);
302: stopclock();
303: if (amount > 0)
304: printstats("Received", amount);
305: }
306:
307: static int
308: makerequest(request, name, tp, mode)
309: int request;
310: const char *name;
311: struct tftphdr *tp;
312: const char *mode;
313: {
1.9 mpech 314: char *cp;
1.1 deraadt 315:
316: tp->th_opcode = htons((u_short)request);
317: cp = tp->th_stuff;
318: strcpy(cp, name);
319: cp += strlen(name);
320: *cp++ = '\0';
321: strcpy(cp, mode);
322: cp += strlen(mode);
323: *cp++ = '\0';
324: return (cp - (char *)tp);
325: }
326:
327: struct errmsg {
328: int e_code;
329: char *e_msg;
330: } errmsgs[] = {
331: { EUNDEF, "Undefined error code" },
332: { ENOTFOUND, "File not found" },
333: { EACCESS, "Access violation" },
334: { ENOSPACE, "Disk full or allocation exceeded" },
335: { EBADOP, "Illegal TFTP operation" },
336: { EBADID, "Unknown transfer ID" },
337: { EEXISTS, "File already exists" },
338: { ENOUSER, "No such user" },
1.8 mpech 339: { -1, NULL }
1.1 deraadt 340: };
341:
342: /*
343: * Send a nak packet (error message).
344: * Error code passed in is one of the
345: * standard TFTP codes, or a UNIX errno
346: * offset by 100.
347: */
348: static void
349: nak(error)
350: int error;
351: {
1.9 mpech 352: struct errmsg *pe;
353: struct tftphdr *tp;
1.1 deraadt 354: int length;
355:
356: tp = (struct tftphdr *)ackbuf;
357: tp->th_opcode = htons((u_short)ERROR);
358: tp->th_code = htons((u_short)error);
359: for (pe = errmsgs; pe->e_code >= 0; pe++)
360: if (pe->e_code == error)
361: break;
362: if (pe->e_code < 0) {
363: pe->e_msg = strerror(error - 100);
364: tp->th_code = EUNDEF;
365: }
1.8 mpech 366: length = strlcpy(tp->th_msg, pe->e_msg, sizeof(ackbuf)) + 5;
367: if (length > sizeof(ackbuf))
368: length = sizeof(ackbuf);
1.1 deraadt 369: if (trace)
370: tpacket("sent", tp, length);
371: if (sendto(f, ackbuf, length, 0, (struct sockaddr *)&peeraddr,
372: sizeof(peeraddr)) != length)
1.7 mickey 373: warn("nak");
1.1 deraadt 374: }
375:
376: static void
377: tpacket(s, tp, n)
378: const char *s;
379: struct tftphdr *tp;
380: int n;
381: {
382: static char *opcodes[] =
383: { "#0", "RRQ", "WRQ", "DATA", "ACK", "ERROR" };
1.9 mpech 384: char *cp, *file;
1.1 deraadt 385: u_short op = ntohs(tp->th_opcode);
386:
387: if (op < RRQ || op > ERROR)
388: printf("%s opcode=%x ", s, op);
389: else
390: printf("%s %s ", s, opcodes[op]);
391: switch (op) {
392:
393: case RRQ:
394: case WRQ:
395: n -= 2;
396: file = cp = tp->th_stuff;
1.3 millert 397: cp = strchr(cp, '\0');
1.1 deraadt 398: printf("<file=%s, mode=%s>\n", file, cp + 1);
399: break;
400:
401: case DATA:
402: printf("<block=%d, %d bytes>\n", ntohs(tp->th_block), n - 4);
403: break;
404:
405: case ACK:
406: printf("<block=%d>\n", ntohs(tp->th_block));
407: break;
408:
409: case ERROR:
410: printf("<code=%d, msg=%s>\n", ntohs(tp->th_code), tp->th_msg);
411: break;
412: }
413: }
414:
415: struct timeval tstart;
416: struct timeval tstop;
417:
418: static void
419: startclock()
420: {
421:
422: (void)gettimeofday(&tstart, NULL);
423: }
424:
425: static void
426: stopclock()
427: {
428:
429: (void)gettimeofday(&tstop, NULL);
430: }
431:
432: static void
433: printstats(direction, amount)
434: const char *direction;
435: unsigned long amount;
436: {
437: double delta;
438: /* compute delta in 1/10's second units */
439: delta = ((tstop.tv_sec*10.)+(tstop.tv_usec/100000)) -
440: ((tstart.tv_sec*10.)+(tstart.tv_usec/100000));
441: delta = delta/10.; /* back to seconds */
1.6 deraadt 442: printf("%s %lu bytes in %.1f seconds", direction, amount, delta);
1.1 deraadt 443: if (verbose)
444: printf(" [%.0f bits/sec]", (amount*8.)/delta);
445: putchar('\n');
446: }
447:
448: static void
449: timer(sig)
450: int sig;
451: {
1.4 deraadt 452: int save_errno = errno;
1.1 deraadt 453:
454: timeout += rexmtval;
455: if (timeout >= maxtimeout) {
456: printf("Transfer timed out.\n");
1.4 deraadt 457: errno = save_errno;
1.1 deraadt 458: longjmp(toplevel, -1);
459: }
1.4 deraadt 460: errno = save_errno;
1.1 deraadt 461: longjmp(timeoutbuf, 1);
462: }