freebsd-skq/usr.bin/tftp/tftp.c
Alan Somers ca2d3691c3 Fix several Coverity warnings in tftp
Some of the changes are in the libexec/tftpd directory, but to functions that
are only used by tftp(1) (they share some code).

* strcpy => strlcpy (1006793, 1006794, 1006796, 1006741)
* Unchecked return value and TOCTTOU (1009314)
* NULL pointer dereference (1018035, 1018036)

Reported by:	Coverity
CID:		1006793, 1006794, 1006796, 1006741, 1009314, 1018035
CID:		1018036
MFC after:	2 weeks
2018-07-22 17:10:12 +00:00

275 lines
6.5 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* 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. 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/socket.h>
#include <sys/stat.h>
#include <netinet/in.h>
#include <arpa/tftp.h>
#include <assert.h>
#include <err.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include "tftp.h"
#include "tftp-file.h"
#include "tftp-utils.h"
#include "tftp-io.h"
#include "tftp-transfer.h"
#include "tftp-options.h"
/*
* Send the requested file.
*/
void
xmitfile(int peer, char *port, int fd, char *name, char *mode)
{
struct tftphdr *rp;
int n, i;
uint16_t block;
struct sockaddr_storage serv; /* valid server port number */
char recvbuffer[MAXPKTSIZE];
struct tftp_stats tftp_stats;
stats_init(&tftp_stats);
memset(&serv, 0, sizeof(serv));
rp = (struct tftphdr *)recvbuffer;
if (port == NULL) {
struct servent *se;
se = getservbyname("tftp", "udp");
assert(se != NULL);
((struct sockaddr_in *)&peer_sock)->sin_port = se->s_port;
} else
((struct sockaddr_in *)&peer_sock)->sin_port =
htons(atoi(port));
for (i = 0; i < 12; i++) {
struct sockaddr_storage from;
/* Tell the other side what we want to do */
if (debug&DEBUG_SIMPLE)
printf("Sending %s\n", name);
n = send_wrq(peer, name, mode);
if (n > 0) {
printf("Cannot send WRQ packet\n");
return;
}
/*
* The first packet we receive has the new destination port
* we have to send the next packets to.
*/
n = receive_packet(peer, recvbuffer,
MAXPKTSIZE, &from, timeoutpacket);
/* We got some data! */
if (n >= 0) {
((struct sockaddr_in *)&peer_sock)->sin_port =
((struct sockaddr_in *)&from)->sin_port;
break;
}
/* This should be retried */
if (n == RP_TIMEOUT) {
printf("Try %d, didn't receive answer from remote.\n",
i + 1);
continue;
}
/* Everything else is fatal */
break;
}
if (i == 12) {
printf("Transfer timed out.\n");
return;
}
if (rp->th_opcode == ERROR) {
printf("Got ERROR, aborted\n");
return;
}
/*
* If the first packet is an OACK instead of an ACK packet,
* handle it different.
*/
if (rp->th_opcode == OACK) {
if (!options_rfc_enabled) {
printf("Got OACK while options are not enabled!\n");
send_error(peer, EBADOP);
return;
}
parse_options(peer, rp->th_stuff, n + 2);
}
if (read_init(fd, NULL, mode) < 0) {
warn("read_init()");
return;
}
block = 1;
tftp_send(peer, &block, &tftp_stats);
read_close();
if (tftp_stats.amount > 0)
printstats("Sent", verbose, &tftp_stats);
txrx_error = 1;
}
/*
* Receive a file.
*/
void
recvfile(int peer, char *port, int fd, char *name, char *mode)
{
struct tftphdr *rp;
uint16_t block;
char recvbuffer[MAXPKTSIZE];
int n, i;
struct tftp_stats tftp_stats;
stats_init(&tftp_stats);
rp = (struct tftphdr *)recvbuffer;
if (port == NULL) {
struct servent *se;
se = getservbyname("tftp", "udp");
assert(se != NULL);
((struct sockaddr_in *)&peer_sock)->sin_port = se->s_port;
} else
((struct sockaddr_in *)&peer_sock)->sin_port =
htons(atoi(port));
for (i = 0; i < 12; i++) {
struct sockaddr_storage from;
/* Tell the other side what we want to do */
if (debug&DEBUG_SIMPLE)
printf("Requesting %s\n", name);
n = send_rrq(peer, name, mode);
if (n > 0) {
printf("Cannot send RRQ packet\n");
return;
}
/*
* The first packet we receive has the new destination port
* we have to send the next packets to.
*/
n = receive_packet(peer, recvbuffer,
MAXPKTSIZE, &from, timeoutpacket);
/* We got something useful! */
if (n >= 0) {
((struct sockaddr_in *)&peer_sock)->sin_port =
((struct sockaddr_in *)&from)->sin_port;
break;
}
/* We should retry if this happens */
if (n == RP_TIMEOUT) {
printf("Try %d, didn't receive answer from remote.\n",
i + 1);
continue;
}
/* Otherwise it is a fatal error */
break;
}
if (i == 12) {
printf("Transfer timed out.\n");
return;
}
if (rp->th_opcode == ERROR) {
tftp_log(LOG_ERR, "Error code %d: %s", rp->th_code, rp->th_msg);
return;
}
if (write_init(fd, NULL, mode) < 0) {
warn("write_init");
return;
}
/*
* If the first packet is an OACK packet instead of an DATA packet,
* handle it different.
*/
if (rp->th_opcode == OACK) {
if (!options_rfc_enabled) {
printf("Got OACK while options are not enabled!\n");
send_error(peer, EBADOP);
return;
}
parse_options(peer, rp->th_stuff, n + 2);
n = send_ack(peer, 0);
if (n > 0) {
printf("Cannot send ACK on OACK.\n");
return;
}
block = 0;
tftp_receive(peer, &block, &tftp_stats, NULL, 0);
} else {
block = 1;
tftp_receive(peer, &block, &tftp_stats, rp, n);
}
if (tftp_stats.amount > 0)
printstats("Received", verbose, &tftp_stats);
return;
}