/****************************************************************************
* apps/netutils/ftpc/ftpc_transfer.c
*
* Copyright (C) 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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 NuttX 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 COPYRIGHT HOLDERS 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
* COPYRIGHT OWNER 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <sys/stat.h>
#include <sys/time.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <signal.h>
#include <poll.h>
#include <ctype.h>
#include <errno.h>
#include <assert.h>
#include <debug.h>
#include <arpa/inet.h>
#include "netutils/ftpc.h"
#include "netutils/netlib.h"
#include "ftpc_internal.h"
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: ftp_cmd_epsv
*
* Description:
* Enter passive mode using EPSV command.
*
* In active mode FTP the client connects from a random port (N>1023) to
* the FTP server's command port, port 21. Then the client starts listening
* to port N+1 and sends the FTP command PORT N+1 to the FTP server. The
* server will then connect back to the client's specified data port from
* its local data port, which is port 20. In passive mode FTP the client
* initiates both connections to the server, solving the problem of
* firewalls filtering the incoming data port connection to the client from
* the server. When opening an FTP connection, the client opens two random
* ports locally (N>1023 and N+1). The first port contacts the server on
* port 21, but instead of then issuing a PORT command and allowing the
* server to connect back to its data port, the client will issue the PASV
* command. The result of this is that the server then opens a random
* unprivileged port (P > 1023) and sends the PORT P command back to the
* client. The client then initiates the connection from port N+1 to port
* P on the server to transfer data.
*
****************************************************************************/
#ifndef CONFIG_FTPC_DISABLE_EPSV
static int ftp_cmd_epsv(FAR struct ftpc_session_s *session,
FAR union ftpc_sockaddr_u *addr)
{
char *ptr;
int nscan;
int ret;
uint16_t tmp;
/* Request passive mode. The server normally accepts EPSV with code 227.
* Its response is a single line showing the IP address of the server and
* the TCP port number where the server is accepting connections.
*/
ret = ftpc_cmd(session, "EPSV");
if (ret < 0 || !ftpc_connected(session))
{
return ERROR;
}
/* Skip over any leading stuff before important data begins */
ptr = session->reply + 4;
while (*ptr != '(')
{
ptr++;
if (ptr > (session->reply + sizeof(session->reply) - 1))
{
nwarn("WARNING: Error parsing EPSV reply: '%s'\n", session->reply);
return ERROR;
}
}
ptr++;
/* The response is then just the port number. None of the other fields
* are supplied.
*/
nscan = sscanf(ptr, "|||%hu|", &tmp);
if (nscan != 1)
{
nwarn("WARNING: Error parsing EPSV reply: '%s'\n", session->reply);
return ERROR;
}
#ifdef CONFIG_NET_IPv4
if (addr->sa.sa_family == AF_INET)
{
addr->in4.sin_port = HTONS(tmp);
}
#endif
#ifdef CONFIG_NET_IPv6
if (addr->sa.sa_family == AF_INET6)
{
addr->in6.sin6_port = HTONS(tmp);
}
#endif
return OK;
}
#endif
/****************************************************************************
* Name: ftp_cmd_pasv
*
* Description:
* Enter passive mode using PASV command.
*
* In active mode FTP the client connects from a random port (N>1023) to
* the FTP server's command port, port 21. Then the client starts listening
* to port N+1 and sends the FTP command PORT N+1 to the FTP server. The
* server will then connect back to the client's specified data port from
* its local data port, which is port 20. In passive mode FTP the client
* initiates both connections to the server, solving the problem of
* firewalls filtering the incoming data port connection to the client from
* the server. When opening an FTP connection, the client opens two random
* ports locally (N>1023 and N+1). The first port contacts the server on
* port 21, but instead of then issuing a PORT command and allowing the
* server to connect back to its data port, the client will issue the PASV
* of this is that the server then opens a random unprivileged port (P >
* command. The result 1023) and sends the PORT P command back to the
* client. The client then initiates the connection from port N+1 to port P
* on the server to transfer data.
*
****************************************************************************/
#ifdef CONFIG_FTPC_DISABLE_EPSV
static int ftp_cmd_pasv(FAR struct ftpc_session_s *session,
FAR union ftpc_sockaddr_u *addr)
{
int tmpap[6];
char *ptr;
int nscan;
int ret;
/* Request passive mode. The server normally accepts PASV with code 227.
* Its response is a single line showing the IP address of the server and
* the TCP port number where the server is accepting connections.
*/
ret = ftpc_cmd(session, "PASV");
if (ret < 0 || !ftpc_connected(session))
{
return ERROR;
}
/* Skip over any leading stuff before important data begins */
ptr = session->reply + 4;
while (*ptr != '\0' && !isdigit((int)*ptr))
{
ptr++;
}
/* The response is then 6 integer values: four representing the
* IP address and two representing the port number.
*/
nscan = sscanf(ptr, "%d,%d,%d,%d,%d,%d",
&tmpap[0], &tmpap[1], &tmpap[2],
&tmpap[3], &tmpap[4], &tmpap[5]);
if (nscan != 6)
{
nwarn("WARNING: Error parsing PASV reply: '%s'\n", session->reply);
return ERROR;
}
/* Then copy the sscanf'ed values as bytes */
memcpy(&addr->in4.sin_addr, tmpap, sizeof(addr->in4.sin_addr));
memcpy(&addr->in4.sin_port, &tmpap[4], sizeof(addr->in4.sin_port));
return OK;
}
#endif
/****************************************************************************
* Name: ftpc_abspath
*
* Description:
* Get the absolute path to a file, handling tilde expansion.
*
****************************************************************************/
static FAR char *ftpc_abspath(FAR struct ftpc_session_s *session,
FAR const char *relpath,
FAR const char *homedir,
FAR const char *curdir)
{
FAR char *ptr = NULL;
/* If no relative path was provide,
* then use the current working directory
*/
if (!relpath)
{
return strdup(curdir);
}
/* Handle tilde expansion */
if (relpath[0] == '~')
{
/* Is the relative path only '~' */
if (relpath[1] == '\0')
{
return strdup(homedir);
}
/* No... then a '/' better follow the tilde */
else if (relpath[1] == '/')
{
asprintf(&ptr, "%s%s", homedir, &relpath[1]);
}
/* Hmmm... this pretty much guaranteed to fail */
else
{
ptr = strdup(relpath);
}
}
/* No tilde expansion. Check for a path relative to the current
* directory.
*/
else if (strncmp(relpath, "./", 2) == 0)
{
asprintf(&ptr, "%s%s", curdir, relpath + 1);
}
/* Check for an absolute path */
else if (relpath[0] == '/')
{
ptr = strdup(relpath);
}
/* Assume it a relative path */
else
{
asprintf(&ptr, "%s/%s", curdir, relpath);
}
return ptr;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: ftpc_xfrinit
*
* Description:
* Perform common transfer setup logic.
*
****************************************************************************/
int ftpc_xfrinit(FAR struct ftpc_session_s *session)
{
union ftpc_sockaddr_u addr;
int ret;
#ifdef CONFIG_FTPC_DISABLE_EPRT
uint8_t *paddr;
uint8_t *pport;
#else
char ipstr[48];
#endif
/* We must be connected to initiate a transfer */
if (!ftpc_connected(session))
{
nerr("ERROR: Not connected\n");
goto errout;
}
/* Should we enter passive mode? */
if (FTPC_IS_PASSIVE(session))
{
/* Initialize the data channel */
ret = ftpc_sockinit(&session->data, session->server.sa.sa_family);
if (ret != OK)
{
nerr("ERROR: ftpc_sockinit() failed: %d\n", errno);
goto errout;
}
/* Does this host support the PASV command */
if (!FTPC_HAS_PASV(session))
{
nerr("ERROR: Host doesn't support passive mode\n");
goto errout_with_data;
}
/* Configure the address to be the server address. If EPSV is used, the
* port will be populated by parsing the reply of the EPSV command. If
* the PASV command is used, the address and port will be overwritten.
*/
memcpy(&addr, &session->server, sizeof(union ftpc_sockaddr_u));
/* Yes.. going passive. */
#ifdef CONFIG_FTPC_DISABLE_EPSV
ret = ftp_cmd_pasv(session, &addr);
if (ret < 0)
{
nerr("ERROR: ftp_cmd_pasv() failed: %d\n", errno);
goto errout_with_data;
}
#else
ret = ftp_cmd_epsv(session, &addr);
if (ret < 0)
{
nerr("ERROR: ftp_cmd_epsv() failed: %d\n", errno);
goto errout_with_data;
}
#endif
/* Connect the data socket */
ret = ftpc_sockconnect(&session->data, (FAR struct sockaddr *)&addr);
if (ret < 0)
{
nerr("ERROR: ftpc_sockconnect() failed: %d\n", errno);
goto errout_with_data;
}
}
else
{
/* Initialize the data listener socket that allows us to accept new
* data connections from the server
*/
ret = ftpc_sockinit(&session->dacceptor, session->server.sa.sa_family);
if (ret != OK)
{
nerr("ERROR: ftpc_sockinit() failed: %d\n", errno);
goto errout;
}
/* Use the server IP address to find the network interface, and
* subsequent local IP address used to establish the active
* connection. We must send the IP and port to the server so that
* it knows how to connect.
*/
#ifdef CONFIG_NET_IPv6
if (session->server.sa.sa_family == AF_INET6)
{
ret = netlib_ipv6adaptor(&session->server.in6.sin6_addr,
&session->dacceptor.laddr.in6.sin6_addr);
if (ret < 0)
{
nerr("ERROR: netlib_ipv6adaptor() failed: %d\n", ret);
goto errout_with_data;
}
}
else
#endif
#ifdef CONFIG_NET_IPv4
if (session->server.sa.sa_family == AF_INET)
{
ret = netlib_ipv4adaptor(session->server.in4.sin_addr.s_addr,
&session->dacceptor.laddr.in4.sin_addr.s_addr);
if (ret < 0)
{
nerr("ERROR: netlib_ipv4adaptor() failed: %d\n", ret);
goto errout_with_data;
}
}
else
#endif
{
nerr("ERROR: unsupported address family\n");
goto errout_with_data;
}
/* Wait for the connection to be established */
ftpc_socklisten(&session->dacceptor);
#ifdef CONFIG_FTPC_DISABLE_EPRT
/* Then send our local data channel address to the server */
paddr = (uint8_t *)&session->dacceptor.laddr.in4.sin_addr;
pport = (uint8_t *)&session->dacceptor.laddr.in4.sin_port;
ret = ftpc_cmd(session, "PORT %d,%d,%d,%d,%d,%d",
paddr[0], paddr[1], paddr[2],
paddr[3], pport[0], pport[1]);
#else
#ifdef CONFIG_NET_IPv6
if (session->dacceptor.laddr.sa.sa_family == AF_INET6)
{
if (!inet_ntop(AF_INET6, &session->dacceptor.laddr.in6.sin6_addr,
ipstr, 48))
{
nerr("ERROR: inet_ntop failed: %d\n", errno);
goto errout_with_data;
}
ret = ftpc_cmd(session, "EPRT |2|%s|%d|", ipstr,
session->dacceptor.laddr.in6.sin6_port);
}
else
#endif /* CONFIG_NET_IPv6 */
#ifdef CONFIG_NET_IPv4
if (session->dacceptor.laddr.sa.sa_family == AF_INET)
{
if (!inet_ntop(AF_INET, &session->dacceptor.laddr.in4.sin_addr,
ipstr, 48))
{
nerr("ERROR: inet_ntop failed: %d\n", errno);
goto errout_with_data;
}
ret = ftpc_cmd(session, "EPRT |1|%s|%d|", ipstr,
session->dacceptor.laddr.in4.sin_port);
}
else
#endif /* CONFIG_NET_IPv4 */
#endif /* CONFIG_FTPC_DISABLE_EPRT */
if (ret < 0)
{
nerr("ERROR: ftpc_cmd() failed: %d\n", errno);
goto errout_with_data;
}
}
return OK;
errout_with_data:
ftpc_sockclose(&session->data);
ftpc_sockclose(&session->dacceptor);
errout:
return ERROR;
}
/****************************************************************************
* Name: ftpc_xfrreset
*
* Description:
* Reset transfer variables
*
****************************************************************************/
void ftpc_xfrreset(struct ftpc_session_s *session)
{
session->size = 0;
session->flags &= ~FTPC_XFER_FLAGS;
}
/****************************************************************************
* Name: ftpc_xfrmode
*
* Description:
* Select ASCII or Binary transfer mode
*
****************************************************************************/
int ftpc_xfrmode(struct ftpc_session_s *session, uint8_t xfrmode)
{
int ret;
/* Check if we have already selected the requested mode */
DEBUGASSERT(xfrmode != FTPC_XFRMODE_UNKNOWN);
if (session->xfrmode != xfrmode)
{
/* Send the TYPE request to control the binary flag.
* Parameters for the TYPE request include:
*
* A: Turn the binary flag off.
* A N: Turn the binary flag off.
* I: Turn the binary flag on.
* L 8: Turn the binary flag on.
*
* The server accepts the TYPE request with code 200.
*/
ret = ftpc_cmd(session, "TYPE %c",
xfrmode == FTPC_XFRMODE_ASCII ? 'A' : 'I');
if (ret < 0)
{
return ERROR;
}
session->xfrmode = xfrmode;
}
return OK;
}
/****************************************************************************
* Name: ftpc_xfrabort
*
* Description:
* Abort a transfer in progress
*
****************************************************************************/
int ftpc_xfrabort(FAR struct ftpc_session_s *session, FAR FILE *stream)
{
FAR struct pollfd fds;
int ret;
/* Make sure that we are still connected */
if (!ftpc_connected(session))
{
return ERROR;
}
/* Check if there is data waiting to be read from the cmd channel */
fds.fd = session->cmd.sd;
fds.events = POLLIN;
ret = poll(&fds, 1, 0);
if (ret > 0)
{
/* Read data from command channel */
ninfo("Flush cmd channel data\n");
while (stream &&
fread(session->buffer, 1, CONFIG_FTP_BUFSIZE, stream) > 0);
return OK;
}
FTPC_SET_INTERRUPT(session);
/* Send the Telnet interrupt sequence to abort the transfer:
* <IAC IP><IAC DM>ABORT<CR><LF>
*/
ninfo("Telnet ABORt sequence\n");
ftpc_sockprintf(&session->cmd, "%c%c", TELNET_IAC, TELNET_IP); /* Interrupt process */
ftpc_sockprintf(&session->cmd, "%c%c", TELNET_IAC, TELNET_DM); /* Telnet synch signal */
ftpc_sockprintf(&session->cmd, "ABOR\r\n"); /* Abort */
ftpc_sockflush(&session->cmd);
/* Read remaining bytes from connection */
while (stream &&
fread(session->buffer, 1, CONFIG_FTP_BUFSIZE, stream) > 0);
/* Get the ABORt reply */
fptc_getreply(session);
/* Expected replies are: "226 Closing data connection" or
* "426 Connection closed; transfer aborted"
*/
if (session->code != 226 && session->code != 426)
{
ninfo("Expected 226 or 426 reply\n");
}
else
{
/* Get the next reply */
fptc_getreply(session);
/* Expected replies are: "226 Closing data connection" or
* "225 Data connection open; no transfer in progress"
*/
if (session->code != 226 && session->code != 225)
{
ninfo("Expected 225 or 226 reply\n");
}
}
return ERROR;
}
/****************************************************************************
* Name: ftpc_timeout
*
* Description:
* A timeout occurred -- either on a specific command or while waiting
* for a reply.
*
* NOTE:
* This function executes in the context of a timer interrupt handler.
*
****************************************************************************/
void ftpc_timeout(wdparm_t arg)
{
FAR struct ftpc_session_s *session = (FAR struct ftpc_session_s *)arg;
nerr("ERROR: Timeout!\n");
DEBUGASSERT(session);
kill(session->pid, CONFIG_FTP_SIGNAL);
}
/****************************************************************************
* Name: ftpc_absrpath
*
* Description:
* Get the absolute path to a remote file, handling tilde expansion.
*
****************************************************************************/
FAR char *ftpc_absrpath(FAR struct ftpc_session_s *session,
FAR const char *relpath)
{
FAR char *absrpath = ftpc_abspath(session, relpath,
session->homerdir, session->currdir);
ninfo("%s -> %s\n", relpath, absrpath);
return absrpath;
}
/****************************************************************************
* Name: ftpc_abslpath
*
* Description:
* Get the absolute path to a local file, handling tilde expansion.
*
****************************************************************************/
FAR char *ftpc_abslpath(FAR struct ftpc_session_s *session,
FAR const char *relpath)
{
FAR char *abslpath = ftpc_abspath(session, relpath,
session->homeldir, session->curldir);
ninfo("%s -> %s\n", relpath, abslpath);
return abslpath;
}