freebsd-dev/usr.sbin/faithd/ftp.c

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/* $KAME: ftp.c,v 1.24 2005/03/16 05:05:48 itojun Exp $ */
/*
* Copyright (C) 1997 and 1998 WIDE Project.
* 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 project 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 PROJECT 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 PROJECT 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.
*
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#ifdef HAVE_POLL_H
#include <poll.h>
#endif
#include <errno.h>
#include <ctype.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include "faithd.h"
static char rbuf[MSS];
static char sbuf[MSS];
static int passivemode = 0;
static int wport4 = -1; /* listen() to active */
static int wport6 = -1; /* listen() to passive */
static int port4 = -1; /* active: inbound passive: outbound */
static int port6 = -1; /* active: outbound passive: inbound */
static struct sockaddr_storage data4; /* server data address */
static struct sockaddr_storage data6; /* client data address */
static int epsvall = 0;
enum state { NONE, LPRT, EPRT, LPSV, EPSV };
2007-11-07 10:53:41 +00:00
static int ftp_activeconn(void);
static int ftp_passiveconn(void);
static int ftp_copy(int, int);
static int ftp_copyresult(int, int, enum state);
static int ftp_copycommand(int, int, enum state *);
void
ftp_relay(int ctl6, int ctl4)
{
#ifdef HAVE_POLL_H
struct pollfd pfd[6];
#else
fd_set readfds;
#endif
int error;
enum state state = NONE;
struct timeval tv;
syslog(LOG_INFO, "starting ftp control connection");
for (;;) {
#ifdef HAVE_POLL_H
pfd[0].fd = ctl4;
pfd[0].events = POLLIN;
pfd[1].fd = ctl6;
pfd[1].events = POLLIN;
if (0 <= port4) {
pfd[2].fd = port4;
pfd[2].events = POLLIN;
} else
pfd[2].fd = -1;
if (0 <= port6) {
pfd[3].fd = port6;
pfd[3].events = POLLIN;
} else
pfd[3].fd = -1;
#if 0
if (0 <= wport4) {
pfd[4].fd = wport4;
pfd[4].events = POLLIN;
} else
pfd[4].fd = -1;
if (0 <= wport6) {
pfd[5].fd = wport4;
pfd[5].events = POLLIN;
} else
pfd[5].fd = -1;
#else
pfd[4].fd = pfd[5].fd = -1;
pfd[4].events = pfd[5].events = 0;
#endif
#else
int maxfd = 0;
FD_ZERO(&readfds);
if (ctl4 >= FD_SETSIZE)
exit_failure("descriptor too big");
FD_SET(ctl4, &readfds);
maxfd = ctl4;
if (ctl6 >= FD_SETSIZE)
exit_failure("descriptor too big");
FD_SET(ctl6, &readfds);
maxfd = (ctl6 > maxfd) ? ctl6 : maxfd;
if (0 <= port4) {
if (port4 >= FD_SETSIZE)
exit_failure("descriptor too big");
FD_SET(port4, &readfds);
maxfd = (port4 > maxfd) ? port4 : maxfd;
}
if (0 <= port6) {
if (port6 >= FD_SETSIZE)
exit_failure("descriptor too big");
FD_SET(port6, &readfds);
maxfd = (port6 > maxfd) ? port6 : maxfd;
}
#if 0
if (0 <= wport4) {
if (wport4 >= FD_SETSIZE)
exit_failure("descriptor too big");
FD_SET(wport4, &readfds);
maxfd = (wport4 > maxfd) ? wport4 : maxfd;
}
if (0 <= wport6) {
if (wport6 >= FD_SETSIZE)
exit_failure("descriptor too big");
FD_SET(wport6, &readfds);
maxfd = (wport6 > maxfd) ? wport6 : maxfd;
}
#endif
#endif
tv.tv_sec = FAITH_TIMEOUT;
tv.tv_usec = 0;
#ifdef HAVE_POLL_H
error = poll(pfd, sizeof(pfd)/sizeof(pfd[0]), tv.tv_sec * 1000);
#else
error = select(maxfd + 1, &readfds, NULL, NULL, &tv);
#endif
if (error == -1) {
#ifdef HAVE_POLL_H
exit_failure("poll: %s", strerror(errno));
#else
exit_failure("select: %s", strerror(errno));
#endif
}
else if (error == 0)
exit_failure("connection timeout");
/*
* The order of the following checks does (slightly) matter.
* It is important to visit all checks (do not use "continue"),
* otherwise some of the pipe may become full and we cannot
* relay correctly.
*/
#ifdef HAVE_POLL_H
if (pfd[1].revents & POLLIN)
#else
if (FD_ISSET(ctl6, &readfds))
#endif
{
/*
* copy control connection from the client.
* command translation is necessary.
*/
error = ftp_copycommand(ctl6, ctl4, &state);
if (error < 0)
goto bad;
else if (error == 0) {
close(ctl4);
close(ctl6);
exit_success("terminating ftp control connection");
/*NOTREACHED*/
}
}
#ifdef HAVE_POLL_H
if (pfd[0].revents & POLLIN)
#else
if (FD_ISSET(ctl4, &readfds))
#endif
{
/*
* copy control connection from the server
* translation of result code is necessary.
*/
error = ftp_copyresult(ctl4, ctl6, state);
if (error < 0)
goto bad;
else if (error == 0) {
close(ctl4);
close(ctl6);
exit_success("terminating ftp control connection");
/*NOTREACHED*/
}
}
#ifdef HAVE_POLL_H
if (0 <= port4 && 0 <= port6 && (pfd[2].revents & POLLIN))
#else
if (0 <= port4 && 0 <= port6 && FD_ISSET(port4, &readfds))
#endif
{
/*
* copy data connection.
* no special treatment necessary.
*/
#ifdef HAVE_POLL_H
if (pfd[2].revents & POLLIN)
#else
if (FD_ISSET(port4, &readfds))
#endif
error = ftp_copy(port4, port6);
switch (error) {
case -1:
goto bad;
case 0:
close(port4);
close(port6);
port4 = port6 = -1;
syslog(LOG_INFO, "terminating data connection");
break;
default:
break;
}
}
#ifdef HAVE_POLL_H
if (0 <= port4 && 0 <= port6 && (pfd[3].revents & POLLIN))
#else
if (0 <= port4 && 0 <= port6 && FD_ISSET(port6, &readfds))
#endif
{
/*
* copy data connection.
* no special treatment necessary.
*/
#ifdef HAVE_POLL_H
if (pfd[3].revents & POLLIN)
#else
if (FD_ISSET(port6, &readfds))
#endif
error = ftp_copy(port6, port4);
switch (error) {
case -1:
goto bad;
case 0:
close(port4);
close(port6);
port4 = port6 = -1;
syslog(LOG_INFO, "terminating data connection");
break;
default:
break;
}
}
#if 0
#ifdef HAVE_POLL_H
if (wport4 && (pfd[4].revents & POLLIN))
#else
if (wport4 && FD_ISSET(wport4, &readfds))
#endif
{
/*
* establish active data connection from the server.
*/
ftp_activeconn();
}
#ifdef HAVE_POLL_H
if (wport4 && (pfd[5].revents & POLLIN))
#else
if (wport6 && FD_ISSET(wport6, &readfds))
#endif
{
/*
* establish passive data connection from the client.
*/
ftp_passiveconn();
}
#endif
}
bad:
exit_failure("%s", strerror(errno));
}
static int
ftp_activeconn()
{
socklen_t n;
int error;
#ifdef HAVE_POLL_H
struct pollfd pfd[1];
#else
fd_set set;
#endif
struct timeval timeout;
struct sockaddr *sa;
/* get active connection from server */
#ifdef HAVE_POLL_H
pfd[0].fd = wport4;
pfd[0].events = POLLIN;
#else
FD_ZERO(&set);
if (wport4 >= FD_SETSIZE)
exit_failure("descriptor too big");
FD_SET(wport4, &set);
#endif
timeout.tv_sec = 120;
timeout.tv_usec = 0;
n = sizeof(data4);
#ifdef HAVE_POLL_H
if (poll(pfd, sizeof(pfd)/sizeof(pfd[0]), timeout.tv_sec * 1000) == 0 ||
(port4 = accept(wport4, (struct sockaddr *)&data4, &n)) < 0)
#else
if (select(wport4 + 1, &set, NULL, NULL, &timeout) == 0 ||
(port4 = accept(wport4, (struct sockaddr *)&data4, &n)) < 0)
#endif
{
close(wport4);
wport4 = -1;
syslog(LOG_INFO, "active mode data connection failed");
return -1;
}
/* ask active connection to client */
sa = (struct sockaddr *)&data6;
port6 = socket(sa->sa_family, SOCK_STREAM, 0);
if (port6 == -1) {
close(port4);
close(wport4);
port4 = wport4 = -1;
syslog(LOG_INFO, "active mode data connection failed");
return -1;
}
error = connect(port6, sa, sa->sa_len);
if (error < 0) {
close(port6);
close(port4);
close(wport4);
port6 = port4 = wport4 = -1;
syslog(LOG_INFO, "active mode data connection failed");
return -1;
}
syslog(LOG_INFO, "active mode data connection established");
return 0;
}
static int
ftp_passiveconn()
{
socklen_t len;
int error;
#ifdef HAVE_POLL_H
struct pollfd pfd[1];
#else
fd_set set;
#endif
struct timeval timeout;
struct sockaddr *sa;
/* get passive connection from client */
#ifdef HAVE_POLL_H
pfd[0].fd = wport6;
pfd[0].events = POLLIN;
#else
FD_ZERO(&set);
if (wport6 >= FD_SETSIZE)
exit_failure("descriptor too big");
FD_SET(wport6, &set);
#endif
timeout.tv_sec = 120;
timeout.tv_usec = 0;
len = sizeof(data6);
#ifdef HAVE_POLL_H
if (poll(pfd, sizeof(pfd)/sizeof(pfd[0]), timeout.tv_sec * 1000) == 0 ||
(port6 = accept(wport6, (struct sockaddr *)&data6, &len)) < 0)
#else
if (select(wport6 + 1, &set, NULL, NULL, &timeout) == 0 ||
(port6 = accept(wport6, (struct sockaddr *)&data6, &len)) < 0)
#endif
{
close(wport6);
wport6 = -1;
syslog(LOG_INFO, "passive mode data connection failed");
return -1;
}
/* ask passive connection to server */
sa = (struct sockaddr *)&data4;
port4 = socket(sa->sa_family, SOCK_STREAM, 0);
if (port4 == -1) {
close(wport6);
close(port6);
wport6 = port6 = -1;
syslog(LOG_INFO, "passive mode data connection failed");
return -1;
}
error = connect(port4, sa, sa->sa_len);
if (error < 0) {
close(wport6);
close(port4);
close(port6);
wport6 = port4 = port6 = -1;
syslog(LOG_INFO, "passive mode data connection failed");
return -1;
}
syslog(LOG_INFO, "passive mode data connection established");
return 0;
}
static int
ftp_copy(int src, int dst)
{
int error, atmark, n;
/* OOB data handling */
error = ioctl(src, SIOCATMARK, &atmark);
if (error != -1 && atmark == 1) {
n = read(src, rbuf, 1);
if (n == -1)
goto bad;
send(dst, rbuf, n, MSG_OOB);
#if 0
n = read(src, rbuf, sizeof(rbuf));
if (n == -1)
goto bad;
write(dst, rbuf, n);
return n;
#endif
}
n = read(src, rbuf, sizeof(rbuf));
switch (n) {
case -1:
case 0:
return n;
default:
write(dst, rbuf, n);
return n;
}
bad:
exit_failure("%s", strerror(errno));
/*NOTREACHED*/
return 0; /* to make gcc happy */
}
static int
ftp_copyresult(int src, int dst, enum state state)
{
int error, atmark, n;
socklen_t len;
char *param;
int code;
char *a, *p;
int i;
/* OOB data handling */
error = ioctl(src, SIOCATMARK, &atmark);
if (error != -1 && atmark == 1) {
n = read(src, rbuf, 1);
if (n == -1)
goto bad;
send(dst, rbuf, n, MSG_OOB);
#if 0
n = read(src, rbuf, sizeof(rbuf));
if (n == -1)
goto bad;
write(dst, rbuf, n);
return n;
#endif
}
n = read(src, rbuf, sizeof(rbuf));
if (n <= 0)
return n;
rbuf[n] = '\0';
/*
* parse argument
*/
p = rbuf;
for (i = 0; i < 3; i++) {
if (!isdigit(*p)) {
/* invalid reply */
write(dst, rbuf, n);
return n;
}
p++;
}
if (!isspace(*p)) {
/* invalid reply */
write(dst, rbuf, n);
return n;
}
code = atoi(rbuf);
param = p;
/* param points to first non-command token, if any */
while (*param && isspace(*param))
param++;
if (!*param)
param = NULL;
switch (state) {
case NONE:
if (!passivemode && rbuf[0] == '1') {
if (ftp_activeconn() < 0) {
n = snprintf(rbuf, sizeof(rbuf),
"425 Cannot open data connetion\r\n");
if (n < 0 || n >= sizeof(rbuf))
n = 0;
}
}
if (n)
write(dst, rbuf, n);
return n;
case LPRT:
case EPRT:
/* expecting "200 PORT command successful." */
if (code == 200) {
p = strstr(rbuf, "PORT");
if (p) {
p[0] = (state == LPRT) ? 'L' : 'E';
p[1] = 'P';
}
} else {
close(wport4);
wport4 = -1;
}
write(dst, rbuf, n);
return n;
case LPSV:
case EPSV:
/*
* expecting "227 Entering Passive Mode (x,x,x,x,x,x,x)"
* (in some cases result comes without paren)
*/
if (code != 227) {
passivefail0:
close(wport6);
wport6 = -1;
write(dst, rbuf, n);
return n;
}
{
unsigned int ho[4], po[2];
struct sockaddr_in *sin;
struct sockaddr_in6 *sin6;
u_short port;
/*
* PASV result -> LPSV/EPSV result
*/
p = param;
while (*p && *p != '(' && !isdigit(*p)) /*)*/
p++;
if (!*p)
goto passivefail0; /*XXX*/
if (*p == '(') /*)*/
p++;
n = sscanf(p, "%u,%u,%u,%u,%u,%u",
&ho[0], &ho[1], &ho[2], &ho[3], &po[0], &po[1]);
if (n != 6)
goto passivefail0; /*XXX*/
/* keep PORT parameter */
memset(&data4, 0, sizeof(data4));
sin = (struct sockaddr_in *)&data4;
sin->sin_len = sizeof(*sin);
sin->sin_family = AF_INET;
sin->sin_addr.s_addr = 0;
for (n = 0; n < 4; n++) {
sin->sin_addr.s_addr |=
htonl((ho[n] & 0xff) << ((3 - n) * 8));
}
sin->sin_port = htons(((po[0] & 0xff) << 8) | (po[1] & 0xff));
/* get ready for passive data connection */
memset(&data6, 0, sizeof(data6));
sin6 = (struct sockaddr_in6 *)&data6;
sin6->sin6_len = sizeof(*sin6);
sin6->sin6_family = AF_INET6;
wport6 = socket(sin6->sin6_family, SOCK_STREAM, 0);
if (wport6 == -1) {
passivefail:
n = snprintf(sbuf, sizeof(sbuf),
"500 could not translate from PASV\r\n");
if (n < 0 || n >= sizeof(sbuf))
n = 0;
if (n)
write(src, sbuf, n);
return n;
}
#ifdef IPV6_FAITH
{
int on = 1;
error = setsockopt(wport6, IPPROTO_IPV6, IPV6_FAITH,
&on, sizeof(on));
if (error == -1)
exit_failure("setsockopt(IPV6_FAITH): %s", strerror(errno));
}
#endif
error = bind(wport6, (struct sockaddr *)sin6, sin6->sin6_len);
if (error == -1) {
close(wport6);
wport6 = -1;
goto passivefail;
}
error = listen(wport6, 1);
if (error == -1) {
close(wport6);
wport6 = -1;
goto passivefail;
}
/* transmit LPSV or EPSV */
/*
* addr from dst, port from wport6
*/
len = sizeof(data6);
error = getsockname(wport6, (struct sockaddr *)&data6, &len);
if (error == -1) {
close(wport6);
wport6 = -1;
goto passivefail;
}
sin6 = (struct sockaddr_in6 *)&data6;
port = sin6->sin6_port;
len = sizeof(data6);
error = getsockname(dst, (struct sockaddr *)&data6, &len);
if (error == -1) {
close(wport6);
wport6 = -1;
goto passivefail;
}
sin6 = (struct sockaddr_in6 *)&data6;
sin6->sin6_port = port;
if (state == LPSV) {
a = (char *)&sin6->sin6_addr;
p = (char *)&sin6->sin6_port;
n = snprintf(sbuf, sizeof(sbuf),
"228 Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)\r\n",
6, 16, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
2, UC(p[0]), UC(p[1]));
if (n < 0 || n >= sizeof(sbuf))
n = 0;
if (n)
write(dst, sbuf, n);
passivemode = 1;
return n;
} else {
n = snprintf(sbuf, sizeof(sbuf),
"229 Entering Extended Passive Mode (|||%d|)\r\n",
ntohs(sin6->sin6_port));
if (n < 0 || n >= sizeof(sbuf))
n = 0;
if (n)
write(dst, sbuf, n);
passivemode = 1;
return n;
}
}
}
bad:
exit_failure("%s", strerror(errno));
/*NOTREACHED*/
return 0; /* to make gcc happy */
}
static int
ftp_copycommand(int src, int dst, enum state *state)
{
int error, atmark, n;
socklen_t len;
unsigned int af, hal, ho[16], pal, po[2];
char *a, *p, *q;
char cmd[5], *param;
struct sockaddr_in *sin;
struct sockaddr_in6 *sin6;
enum state nstate;
char ch;
int i;
/* OOB data handling */
error = ioctl(src, SIOCATMARK, &atmark);
if (error != -1 && atmark == 1) {
n = read(src, rbuf, 1);
if (n == -1)
goto bad;
send(dst, rbuf, n, MSG_OOB);
#if 0
n = read(src, rbuf, sizeof(rbuf));
if (n == -1)
goto bad;
write(dst, rbuf, n);
return n;
#endif
}
n = read(src, rbuf, sizeof(rbuf));
if (n <= 0)
return n;
rbuf[n] = '\0';
if (n < 4) {
write(dst, rbuf, n);
return n;
}
/*
* parse argument
*/
p = rbuf;
q = cmd;
for (i = 0; i < 4; i++) {
if (!isalpha(*p)) {
/* invalid command */
write(dst, rbuf, n);
return n;
}
*q++ = islower(*p) ? toupper(*p) : *p;
p++;
}
if (!isspace(*p)) {
/* invalid command */
write(dst, rbuf, n);
return n;
}
*q = '\0';
param = p;
/* param points to first non-command token, if any */
while (*param && isspace(*param))
param++;
if (!*param)
param = NULL;
*state = NONE;
if (strcmp(cmd, "LPRT") == 0 && param) {
/*
* LPRT -> PORT
*/
nstate = LPRT;
close(wport4);
close(wport6);
close(port4);
close(port6);
wport4 = wport6 = port4 = port6 = -1;
if (epsvall) {
n = snprintf(sbuf, sizeof(sbuf), "501 %s disallowed in EPSV ALL\r\n",
cmd);
if (n < 0 || n >= sizeof(sbuf))
n = 0;
if (n)
write(src, sbuf, n);
return n;
}
n = sscanf(param,
"%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u",
&af, &hal, &ho[0], &ho[1], &ho[2], &ho[3],
&ho[4], &ho[5], &ho[6], &ho[7],
&ho[8], &ho[9], &ho[10], &ho[11],
&ho[12], &ho[13], &ho[14], &ho[15],
&pal, &po[0], &po[1]);
if (n != 21 || af != 6 || hal != 16|| pal != 2) {
n = snprintf(sbuf, sizeof(sbuf),
"501 illegal parameter to LPRT\r\n");
if (n < 0 || n >= sizeof(sbuf))
n = 0;
if (n)
write(src, sbuf, n);
return n;
}
/* keep LPRT parameter */
memset(&data6, 0, sizeof(data6));
sin6 = (struct sockaddr_in6 *)&data6;
sin6->sin6_len = sizeof(*sin6);
sin6->sin6_family = AF_INET6;
for (n = 0; n < 16; n++)
sin6->sin6_addr.s6_addr[n] = ho[n];
sin6->sin6_port = htons(((po[0] & 0xff) << 8) | (po[1] & 0xff));
sendport:
/* get ready for active data connection */
len = sizeof(data4);
error = getsockname(dst, (struct sockaddr *)&data4, &len);
if (error == -1) {
lprtfail:
n = snprintf(sbuf, sizeof(sbuf),
"500 could not translate to PORT\r\n");
if (n < 0 || n >= sizeof(sbuf))
n = 0;
if (n)
write(src, sbuf, n);
return n;
}
if (((struct sockaddr *)&data4)->sa_family != AF_INET)
goto lprtfail;
sin = (struct sockaddr_in *)&data4;
sin->sin_port = 0;
wport4 = socket(sin->sin_family, SOCK_STREAM, 0);
if (wport4 == -1)
goto lprtfail;
error = bind(wport4, (struct sockaddr *)sin, sin->sin_len);
if (error == -1) {
close(wport4);
wport4 = -1;
goto lprtfail;
}
error = listen(wport4, 1);
if (error == -1) {
close(wport4);
wport4 = -1;
goto lprtfail;
}
/* transmit PORT */
len = sizeof(data4);
error = getsockname(wport4, (struct sockaddr *)&data4, &len);
if (error == -1) {
close(wport4);
wport4 = -1;
goto lprtfail;
}
if (((struct sockaddr *)&data4)->sa_family != AF_INET) {
close(wport4);
wport4 = -1;
goto lprtfail;
}
sin = (struct sockaddr_in *)&data4;
a = (char *)&sin->sin_addr;
p = (char *)&sin->sin_port;
n = snprintf(sbuf, sizeof(sbuf), "PORT %d,%d,%d,%d,%d,%d\r\n",
UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
UC(p[0]), UC(p[1]));
if (n < 0 || n >= sizeof(sbuf))
n = 0;
if (n)
write(dst, sbuf, n);
*state = nstate;
passivemode = 0;
return n;
} else if (strcmp(cmd, "EPRT") == 0 && param) {
/*
* EPRT -> PORT
*/
char *afp, *hostp, *portp;
struct addrinfo hints, *res;
nstate = EPRT;
close(wport4);
close(wport6);
close(port4);
close(port6);
wport4 = wport6 = port4 = port6 = -1;
if (epsvall) {
n = snprintf(sbuf, sizeof(sbuf), "501 %s disallowed in EPSV ALL\r\n",
cmd);
if (n < 0 || n >= sizeof(sbuf))
n = 0;
if (n)
write(src, sbuf, n);
return n;
}
p = param;
ch = *p++; /* boundary character */
afp = p;
while (*p && *p != ch)
p++;
if (!*p) {
eprtparamfail:
n = snprintf(sbuf, sizeof(sbuf),
"501 illegal parameter to EPRT\r\n");
if (n < 0 || n >= sizeof(sbuf))
n = 0;
if (n)
write(src, sbuf, n);
return n;
}
*p++ = '\0';
hostp = p;
while (*p && *p != ch)
p++;
if (!*p)
goto eprtparamfail;
*p++ = '\0';
portp = p;
while (*p && *p != ch)
p++;
if (!*p)
goto eprtparamfail;
*p++ = '\0';
n = sscanf(afp, "%d", &af);
if (n != 1 || af != 2) {
n = snprintf(sbuf, sizeof(sbuf),
"501 unsupported address family to EPRT\r\n");
if (n < 0 || n >= sizeof(sbuf))
n = 0;
if (n)
write(src, sbuf, n);
return n;
}
memset(&hints, 0, sizeof(hints));
hints.ai_family = AF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
hints.ai_protocol = IPPROTO_TCP;
error = getaddrinfo(hostp, portp, &hints, &res);
if (error) {
n = snprintf(sbuf, sizeof(sbuf),
"501 EPRT: %s\r\n", gai_strerror(error));
if (n < 0 || n >= sizeof(sbuf))
n = 0;
if (n)
write(src, sbuf, n);
return n;
}
if (res->ai_next) {
n = snprintf(sbuf, sizeof(sbuf),
"501 EPRT: %s resolved to multiple addresses\r\n", hostp);
if (n < 0 || n >= sizeof(sbuf))
n = 0;
if (n)
write(src, sbuf, n);
freeaddrinfo(res);
return n;
}
memcpy(&data6, res->ai_addr, res->ai_addrlen);
freeaddrinfo(res);
goto sendport;
} else if (strcmp(cmd, "LPSV") == 0 && !param) {
/*
* LPSV -> PASV
*/
nstate = LPSV;
close(wport4);
close(wport6);
close(port4);
close(port6);
wport4 = wport6 = port4 = port6 = -1;
if (epsvall) {
n = snprintf(sbuf, sizeof(sbuf), "501 %s disallowed in EPSV ALL\r\n",
cmd);
if (n < 0 || n >= sizeof(sbuf))
n = 0;
if (n)
write(src, sbuf, n);
return n;
}
/* transmit PASV */
n = snprintf(sbuf, sizeof(sbuf), "PASV\r\n");
if (n < 0 || n >= sizeof(sbuf))
n = 0;
if (n)
write(dst, sbuf, n);
*state = LPSV;
passivemode = 0; /* to be set to 1 later */
return n;
} else if (strcmp(cmd, "EPSV") == 0 && !param) {
/*
* EPSV -> PASV
*/
close(wport4);
close(wport6);
close(port4);
close(port6);
wport4 = wport6 = port4 = port6 = -1;
n = snprintf(sbuf, sizeof(sbuf), "PASV\r\n");
if (n < 0 || n >= sizeof(sbuf))
n = 0;
if (n)
write(dst, sbuf, n);
*state = EPSV;
passivemode = 0; /* to be set to 1 later */
return n;
} else if (strcmp(cmd, "EPSV") == 0 && param
&& strncasecmp(param, "ALL", 3) == 0 && isspace(param[3])) {
/*
* EPSV ALL
*/
epsvall = 1;
n = snprintf(sbuf, sizeof(sbuf), "200 EPSV ALL command successful.\r\n");
if (n < 0 || n >= sizeof(sbuf))
n = 0;
if (n)
write(src, sbuf, n);
return n;
} else if (strcmp(cmd, "PORT") == 0 || strcmp(cmd, "PASV") == 0) {
/*
* reject PORT/PASV
*/
n = snprintf(sbuf, sizeof(sbuf), "502 %s not implemented.\r\n", cmd);
if (n < 0 || n >= sizeof(sbuf))
n = 0;
if (n)
write(src, sbuf, n);
return n;
} else if (passivemode
&& (strcmp(cmd, "STOR") == 0
|| strcmp(cmd, "STOU") == 0
|| strcmp(cmd, "RETR") == 0
|| strcmp(cmd, "LIST") == 0
|| strcmp(cmd, "NLST") == 0
|| strcmp(cmd, "APPE") == 0)) {
/*
* commands with data transfer. need to care about passive
* mode data connection.
*/
if (ftp_passiveconn() < 0) {
n = snprintf(sbuf, sizeof(sbuf), "425 Cannot open data connetion\r\n");
if (n < 0 || n >= sizeof(sbuf))
n = 0;
if (n)
write(src, sbuf, n);
} else {
/* simply relay the command */
write(dst, rbuf, n);
}
*state = NONE;
return n;
} else {
/* simply relay it */
*state = NONE;
write(dst, rbuf, n);
return n;
}
bad:
exit_failure("%s", strerror(errno));
/*NOTREACHED*/
return 0; /* to make gcc happy */
}