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mirror of https://git.FreeBSD.org/src.git synced 2024-12-22 11:17:19 +00:00
freebsd/usr.bin/tftp/tftp.c
Brian S. Dean 73f899cae1 To perform even basic error checking, one must have an exit code that
indicates that not everything worked as expected.  Exit non-zero if we
timed out while transmitting or receiving a file or if the file did
not exist, etc.

MFC After:	3 days (re@ willing)
2002-05-12 01:47:50 +00:00

505 lines
12 KiB
C

/*
* Copyright (c) 1983, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if 0
#ifndef lint
static char sccsid[] = "@(#)tftp.c 8.1 (Berkeley) 6/6/93";
#endif /* not lint */
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/* Many bug fixes are from Jim Guyton <guyton@rand-unix> */
/*
* TFTP User Program -- Protocol Machines
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <arpa/tftp.h>
#include <err.h>
#include <errno.h>
#include <setjmp.h>
#include <signal.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <netdb.h>
#include "extern.h"
#include "tftpsubs.h"
extern struct sockaddr_storage peeraddr; /* filled in by main */
extern int f; /* the opened socket */
extern int trace;
extern int verbose;
extern int rexmtval;
extern int maxtimeout;
extern volatile int txrx_error;
#define PKTSIZE SEGSIZE+4
char ackbuf[PKTSIZE];
int timeout;
jmp_buf toplevel;
jmp_buf timeoutbuf;
static void nak(int, struct sockaddr *);
static int makerequest(int, const char *, struct tftphdr *, const char *);
static void printstats(const char *, unsigned long);
static void startclock(void);
static void stopclock(void);
static void timer(int);
static void tpacket(const char *, struct tftphdr *, int);
static int cmpport(struct sockaddr *, struct sockaddr *);
/*
* Send the requested file.
*/
void
xmitfile(fd, name, mode)
int fd;
char *name;
char *mode;
{
struct tftphdr *ap; /* data and ack packets */
struct tftphdr *dp;
int n;
volatile unsigned short block;
volatile int size, convert;
volatile unsigned long amount;
struct sockaddr_storage from;
int fromlen;
FILE *file;
struct sockaddr_storage peer;
struct sockaddr_storage serv; /* valid server port number */
startclock(); /* start stat's clock */
dp = r_init(); /* reset fillbuf/read-ahead code */
ap = (struct tftphdr *)ackbuf;
file = fdopen(fd, "r");
convert = !strcmp(mode, "netascii");
block = 0;
amount = 0;
memcpy(&peer, &peeraddr, peeraddr.ss_len);
memset(&serv, 0, sizeof(serv));
signal(SIGALRM, timer);
do {
if (block == 0)
size = makerequest(WRQ, name, dp, mode) - 4;
else {
/* size = read(fd, dp->th_data, SEGSIZE); */
size = readit(file, &dp, convert);
if (size < 0) {
nak(errno + 100, (struct sockaddr *)&peer);
break;
}
dp->th_opcode = htons((u_short)DATA);
dp->th_block = htons((u_short)block);
}
timeout = 0;
(void) setjmp(timeoutbuf);
send_data:
if (trace)
tpacket("sent", dp, size + 4);
n = sendto(f, dp, size + 4, 0,
(struct sockaddr *)&peer, peer.ss_len);
if (n != size + 4) {
warn("sendto");
goto abort;
}
read_ahead(file, convert);
for ( ; ; ) {
alarm(rexmtval);
do {
fromlen = sizeof(from);
n = recvfrom(f, ackbuf, sizeof(ackbuf), 0,
(struct sockaddr *)&from, &fromlen);
} while (n <= 0);
alarm(0);
if (n < 0) {
warn("recvfrom");
goto abort;
}
if (!serv.ss_family)
serv = from;
else if (!cmpport((struct sockaddr *)&serv,
(struct sockaddr *)&from)) {
warn("server port mismatch");
goto abort;
}
peer = from;
if (trace)
tpacket("received", ap, n);
/* should verify packet came from server */
ap->th_opcode = ntohs(ap->th_opcode);
ap->th_block = ntohs(ap->th_block);
if (ap->th_opcode == ERROR) {
printf("Error code %d: %s\n", ap->th_code,
ap->th_msg);
txrx_error = 1;
goto abort;
}
if (ap->th_opcode == ACK) {
int j;
if (ap->th_block == block) {
break;
}
/* On an error, try to synchronize
* both sides.
*/
j = synchnet(f);
if (j && trace) {
printf("discarded %d packets\n",
j);
}
if (ap->th_block == (block-1)) {
goto send_data;
}
}
}
if (block > 0)
amount += size;
block++;
} while (size == SEGSIZE || block == 1);
abort:
fclose(file);
stopclock();
if (amount > 0)
printstats("Sent", amount);
}
/*
* Receive a file.
*/
void
recvfile(fd, name, mode)
int fd;
char *name;
char *mode;
{
struct tftphdr *ap;
struct tftphdr *dp;
int n;
volatile unsigned short block;
volatile int size, firsttrip;
volatile unsigned long amount;
struct sockaddr_storage from;
int fromlen;
FILE *file;
volatile int convert; /* true if converting crlf -> lf */
struct sockaddr_storage peer;
struct sockaddr_storage serv; /* valid server port number */
startclock();
dp = w_init();
ap = (struct tftphdr *)ackbuf;
file = fdopen(fd, "w");
convert = !strcmp(mode, "netascii");
block = 1;
firsttrip = 1;
amount = 0;
memcpy(&peer, &peeraddr, peeraddr.ss_len);
memset(&serv, 0, sizeof(serv));
signal(SIGALRM, timer);
do {
if (firsttrip) {
size = makerequest(RRQ, name, ap, mode);
firsttrip = 0;
} else {
ap->th_opcode = htons((u_short)ACK);
ap->th_block = htons((u_short)(block));
size = 4;
block++;
}
timeout = 0;
(void) setjmp(timeoutbuf);
send_ack:
if (trace)
tpacket("sent", ap, size);
if (sendto(f, ackbuf, size, 0, (struct sockaddr *)&peer,
peer.ss_len) != size) {
alarm(0);
warn("sendto");
goto abort;
}
write_behind(file, convert);
for ( ; ; ) {
alarm(rexmtval);
do {
fromlen = sizeof(from);
n = recvfrom(f, dp, PKTSIZE, 0,
(struct sockaddr *)&from, &fromlen);
} while (n <= 0);
alarm(0);
if (n < 0) {
warn("recvfrom");
goto abort;
}
if (!serv.ss_family)
serv = from;
else if (!cmpport((struct sockaddr *)&serv,
(struct sockaddr *)&from)) {
warn("server port mismatch");
goto abort;
}
peer = from;
if (trace)
tpacket("received", dp, n);
/* should verify client address */
dp->th_opcode = ntohs(dp->th_opcode);
dp->th_block = ntohs(dp->th_block);
if (dp->th_opcode == ERROR) {
printf("Error code %d: %s\n", dp->th_code,
dp->th_msg);
txrx_error = 1;
goto abort;
}
if (dp->th_opcode == DATA) {
int j;
if (dp->th_block == block) {
break; /* have next packet */
}
/* On an error, try to synchronize
* both sides.
*/
j = synchnet(f);
if (j && trace) {
printf("discarded %d packets\n", j);
}
if (dp->th_block == (block-1)) {
goto send_ack; /* resend ack */
}
}
}
/* size = write(fd, dp->th_data, n - 4); */
size = writeit(file, &dp, n - 4, convert);
if (size < 0) {
nak(errno + 100, (struct sockaddr *)&peer);
break;
}
amount += size;
} while (size == SEGSIZE);
abort: /* ok to ack, since user */
ap->th_opcode = htons((u_short)ACK); /* has seen err msg */
ap->th_block = htons((u_short)block);
(void) sendto(f, ackbuf, 4, 0, (struct sockaddr *)&peer,
peer.ss_len);
write_behind(file, convert); /* flush last buffer */
fclose(file);
stopclock();
if (amount > 0)
printstats("Received", amount);
}
static int
makerequest(request, name, tp, mode)
int request;
const char *name;
struct tftphdr *tp;
const char *mode;
{
char *cp;
tp->th_opcode = htons((u_short)request);
cp = tp->th_stuff;
strcpy(cp, name);
cp += strlen(name);
*cp++ = '\0';
strcpy(cp, mode);
cp += strlen(mode);
*cp++ = '\0';
return (cp - (char *)tp);
}
struct errmsg {
int e_code;
const char *e_msg;
} errmsgs[] = {
{ EUNDEF, "Undefined error code" },
{ ENOTFOUND, "File not found" },
{ EACCESS, "Access violation" },
{ ENOSPACE, "Disk full or allocation exceeded" },
{ EBADOP, "Illegal TFTP operation" },
{ EBADID, "Unknown transfer ID" },
{ EEXISTS, "File already exists" },
{ ENOUSER, "No such user" },
{ -1, 0 }
};
/*
* Send a nak packet (error message).
* Error code passed in is one of the
* standard TFTP codes, or a UNIX errno
* offset by 100.
*/
static void
nak(error, peer)
int error;
struct sockaddr *peer;
{
struct errmsg *pe;
struct tftphdr *tp;
int length;
tp = (struct tftphdr *)ackbuf;
tp->th_opcode = htons((u_short)ERROR);
tp->th_code = htons((u_short)error);
for (pe = errmsgs; pe->e_code >= 0; pe++)
if (pe->e_code == error)
break;
if (pe->e_code < 0) {
pe->e_msg = strerror(error - 100);
tp->th_code = EUNDEF;
}
strcpy(tp->th_msg, pe->e_msg);
length = strlen(pe->e_msg) + 4;
if (trace)
tpacket("sent", tp, length);
if (sendto(f, ackbuf, length, 0, peer, peer->sa_len) != length)
warn("nak");
}
static void
tpacket(s, tp, n)
const char *s;
struct tftphdr *tp;
int n;
{
static const char *opcodes[] =
{ "#0", "RRQ", "WRQ", "DATA", "ACK", "ERROR" };
char *cp, *file;
u_short op = ntohs(tp->th_opcode);
if (op < RRQ || op > ERROR)
printf("%s opcode=%x ", s, op);
else
printf("%s %s ", s, opcodes[op]);
switch (op) {
case RRQ:
case WRQ:
n -= 2;
file = cp = tp->th_stuff;
cp = index(cp, '\0');
printf("<file=%s, mode=%s>\n", file, cp + 1);
break;
case DATA:
printf("<block=%d, %d bytes>\n", ntohs(tp->th_block), n - 4);
break;
case ACK:
printf("<block=%d>\n", ntohs(tp->th_block));
break;
case ERROR:
printf("<code=%d, msg=%s>\n", ntohs(tp->th_code), tp->th_msg);
break;
}
}
struct timeval tstart;
struct timeval tstop;
static void
startclock()
{
(void)gettimeofday(&tstart, NULL);
}
static void
stopclock()
{
(void)gettimeofday(&tstop, NULL);
}
static void
printstats(direction, amount)
const char *direction;
unsigned long amount;
{
double delta;
/* compute delta in 1/10's second units */
delta = ((tstop.tv_sec*10.)+(tstop.tv_usec/100000)) -
((tstart.tv_sec*10.)+(tstart.tv_usec/100000));
delta = delta/10.; /* back to seconds */
printf("%s %ld bytes in %.1f seconds", direction, amount, delta);
if (verbose)
printf(" [%.0f bits/sec]", (amount*8.)/delta);
putchar('\n');
}
static void
timer(sig)
int sig __unused;
{
timeout += rexmtval;
if (timeout >= maxtimeout) {
printf("Transfer timed out.\n");
longjmp(toplevel, -1);
}
txrx_error = 1;
longjmp(timeoutbuf, 1);
}
static int
cmpport(sa, sb)
struct sockaddr *sa;
struct sockaddr *sb;
{
char a[NI_MAXSERV], b[NI_MAXSERV];
if (getnameinfo(sa, sa->sa_len, NULL, 0, a, sizeof(a), NI_NUMERICSERV))
return 0;
if (getnameinfo(sb, sb->sa_len, NULL, 0, b, sizeof(b), NI_NUMERICSERV))
return 0;
if (strcmp(a, b) != 0)
return 0;
return 1;
}