nuttx-apps/netutils/ftpc/ftpc_transfer.c

518 lines
15 KiB
C

/****************************************************************************
* 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 <apps/netutils/ftpc.h>
#include "ftpc_internal.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Private Types
****************************************************************************/
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Public Data
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: ftp_pasvmode
*
* Description:
* Enter passive mode.
*
* 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.
*
****************************************************************************/
static int ftp_pasvmode(struct ftpc_session_s *session,
uint8_t addrport[6])
{
int tmpap[6];
char *ptr;
int nscan;
int ret;
int i;
/* Does this host support the PASV command */
if (!FTPC_HAS_PASV(session))
{
nwarn("WARNING: Host doesn't support passive mode\n");
return ERROR;
}
/* 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 address begins */
ptr = session->reply + 4;
while (!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 */
for (i = 0; i < 6; i++)
{
addrport[i] = (uint8_t)(tmpap[i] & 0xff);
}
return OK;
}
/****************************************************************************
* 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] == '/')
{
(void)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)
{
(void)asprintf(&ptr, "%s%s", curdir, relpath+1);
}
/* Check for an absolute path */
else if (relpath[0] == '/' && relpath[1] == ':' && relpath[2] == '\\')
{
ptr = strdup(relpath);
}
/* Assume it a relative path */
else
{
(void)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)
{
struct sockaddr_in addr;
uint8_t addrport[6];
uint8_t *paddr;
uint8_t *pport;
int ret;
/* We must be connected to initiate a transfer */
if (!ftpc_connected(session))
{
nerr("ERROR: Not connected\n");
goto errout;
}
/* Initialize the data channel */
ret = ftpc_sockinit(&session->data);
if (ret != OK)
{
nerr("ERROR: ftpc_sockinit() failed: %d\n", errno);
goto errout;
}
/* Duplicate the address and connection information of the command channel */
ftpc_sockcopy(&session->data, &session->cmd);
/* Should we enter passive mode? */
if (FTPC_IS_PASSIVE(session))
{
/* Yes.. going passive. */
ret = ftp_pasvmode(session, addrport);
if (ret != OK)
{
nerr("ERROR: ftp_pasvmode() failed: %d\n", errno);
goto errout_with_data;
}
/* Configure the data socket */
ftpc_sockgetsockname(&session->cmd, &addr);
memcpy(&addr.sin_addr, addrport, 4);
memcpy(&addr.sin_port, addrport+4, 2);
/* Connect the data socket */
ret = ftpc_sockconnect(&session->data, &addr);
if (ret < 0)
{
nerr("ERROR: ftpc_sockconnect() failed: %d\n", errno);
goto errout_with_data;
}
}
else
{
/* Wait for the connection to be established */
ftpc_socklisten(&session->data);
/* Then send our local data channel address to the server */
paddr = (uint8_t *)&session->data.laddr.sin_addr;
pport = (uint8_t *)&session->data.laddr.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]);
if (ret < 0)
{
nerr("ERROR: ftpc_cmd() failed: %d\n", errno);
goto errout_with_data;
}
}
return OK;
errout_with_data:
ftpc_sockclose(&session->data);
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');
UNUSED(ret);
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 replys 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 replys are: or "225 Data connection open; no transfer in progress"
* "226 Closing data connection"
*/
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(int argc, uint32_t arg1, ...)
{
FAR struct ftpc_session_s *session = (FAR struct ftpc_session_s *)arg1;
nerr("ERROR: Timeout!\n");
DEBUGASSERT(argc == 1 && 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;
}