ftp.c

/***************************************************************************
 *                                  _   _ ____  _
 *  Project                     ___| | | |  _ \| |
 *                             / __| | | | |_) | |
 *                            | (__| |_| |  _ <| |___
 *                             \___|\___/|_| \_\_____|
 *
 * Copyright (C) 1998 - 2005, Daniel Stenberg, <daniel@haxx.se>, et al.
 *
 * This software is licensed as described in the file COPYING, which
 * you should have received as part of this distribution. The terms
 * are also available at http://curl.haxx.se/docs/copyright.html.
 *
 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
 * copies of the Software, and permit persons to whom the Software is
 * furnished to do so, under the terms of the COPYING file.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 * $Id$
 ***************************************************************************/

#include "setup.h"

#ifndef CURL_DISABLE_FTP
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>
#include <ctype.h>
#include <errno.h>

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#if defined(WIN32) && !defined(__GNUC__) || defined(__MINGW32__)

#else /* probably some kind of unix */
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#include <sys/types.h>
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#ifdef HAVE_UTSNAME_H
#include <sys/utsname.h>
#endif
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
#ifdef  VMS
#include <in.h>
#include <inet.h>
#endif
#endif

#if defined(WIN32) && defined(__GNUC__) || defined(__MINGW32__)
#include <errno.h>
#endif

#if (defined(NETWARE) && defined(__NOVELL_LIBC__))
#undef in_addr_t
#define in_addr_t unsigned long
#endif

#include <curl/curl.h>
#include "urldata.h"
#include "sendf.h"

#include "if2ip.h"
#include "hostip.h"
#include "progress.h"
#include "transfer.h"
#include "escape.h"
#include "http.h" /* for HTTP proxy tunnel stuff */
#include "ftp.h"

#ifdef HAVE_KRB4
#include "security.h"
#include "krb4.h"
#endif

#include "strtoofft.h"
#include "strequal.h"
#include "ssluse.h"
#include "connect.h"
#include "strerror.h"
#include "memory.h"
#include "inet_ntop.h"
#include "select.h"

#if defined(HAVE_INET_NTOA_R) && !defined(HAVE_INET_NTOA_R_DECL)
#include "inet_ntoa_r.h"
#endif

#define _MPRINTF_REPLACE /* use our functions only */
#include <curl/mprintf.h>

/* The last #include file should be: */
#ifdef CURLDEBUG
#include "memdebug.h"
#endif

#ifdef HAVE_NI_WITHSCOPEID
#define NIFLAGS NI_NUMERICHOST | NI_NUMERICSERV | NI_WITHSCOPEID
#else
#define NIFLAGS NI_NUMERICHOST | NI_NUMERICSERV
#endif

/* Local API functions */
static CURLcode ftp_sendquote(struct connectdata *conn,
                              struct curl_slist *quote);
static CURLcode ftp_cwd(struct connectdata *conn, char *path);
static CURLcode ftp_mkd(struct connectdata *conn, char *path);
static CURLcode ftp_cwd_and_mkd(struct connectdata *conn, char *path);
static CURLcode ftp_quit(struct connectdata *conn);
static CURLcode ftp_3rdparty_pretransfer(struct connectdata *conn);
static CURLcode ftp_3rdparty_transfer(struct connectdata *conn);
static CURLcode ftp_parse_url_path(struct connectdata *conn);
static CURLcode ftp_cwd_and_create_path(struct connectdata *conn);
static CURLcode ftp_regular_transfer(struct connectdata *conn);
static CURLcode ftp_3rdparty(struct connectdata *conn);

/* easy-to-use macro: */
#define FTPSENDF(x,y,z) if((result = Curl_ftpsendf(x,y,z))) return result

static void freedirs(struct FTP *ftp)
{
  int i;
  if(ftp->dirs) {
    for (i=0; i < ftp->dirdepth; i++){
      if(ftp->dirs[i]) {
        free(ftp->dirs[i]);
        ftp->dirs[i]=NULL;
      }
    }
    free(ftp->dirs);
    ftp->dirs = NULL;
  }
  if(ftp->file) {
    free(ftp->file);
    ftp->file = NULL;
  }
}

/* Returns non-zero iff the given string contains CR (0x0D) or LF (0x0A), which
   are not allowed within RFC 959 <string>.
 */
static bool isBadFtpString(const char *string)
{
  return strchr(string, 0x0D) != NULL || strchr(string, 0x0A) != NULL;
}

/***********************************************************************
 *
 * AllowServerConnect()
 *
 * When we've issue the PORT command, we have told the server to connect
 * to us. This function will sit and wait here until the server has
 * connected.
 *
 */
static CURLcode AllowServerConnect(struct connectdata *conn)
{
  int timeout_ms;
  struct SessionHandle *data = conn->data;
  curl_socket_t sock = conn->sock[SECONDARYSOCKET];
  struct timeval now = Curl_tvnow();
  long timespent = Curl_tvdiff(Curl_tvnow(), now)/1000;
  long timeout = data->set.connecttimeout?data->set.connecttimeout:
    (data->set.timeout?data->set.timeout: 0);

  if(timeout) {
    timeout -= timespent;
    if(timeout<=0) {
      failf(data, "Timed out before server could connect to us");
      return CURLE_OPERATION_TIMEDOUT;
    }
  }

  /* We allow the server 60 seconds to connect to us, or a custom timeout.
     Note the typecast here. */
  timeout_ms = (timeout?(int)timeout:60) * 1000;

  switch (Curl_select(sock, CURL_SOCKET_BAD, timeout_ms)) {
  case -1: /* error */
    /* let's die here */
    failf(data, "Error while waiting for server connect");
    return CURLE_FTP_PORT_FAILED;
  case 0:  /* timeout */
    /* let's die here */
    failf(data, "Timeout while waiting for server connect");
    return CURLE_FTP_PORT_FAILED;
  default:
    /* we have received data here */
    {
      curl_socket_t s;
      size_t size = sizeof(struct sockaddr_in);
      struct sockaddr_in add;

      getsockname(sock, (struct sockaddr *) &add, (socklen_t *)&size);
      s=accept(sock, (struct sockaddr *) &add, (socklen_t *)&size);

      sclose(sock); /* close the first socket */

      if (CURL_SOCKET_BAD == s) {
        /* DIE! */
        failf(data, "Error accept()ing server connect");
        return CURLE_FTP_PORT_FAILED;
      }
      infof(data, "Connection accepted from server\n");

      conn->sock[SECONDARYSOCKET] = s;
      Curl_nonblock(s, TRUE); /* enable non-blocking */
    }
    break;
  }

  return CURLE_OK;
}


/* --- parse FTP server responses --- */

/*
 * Curl_GetFTPResponse() is supposed to be invoked after each command sent to
 * a remote FTP server. This function will wait and read all lines of the
 * response and extract the relevant return code for the invoking function.
 */

CURLcode Curl_GetFTPResponse(ssize_t *nreadp, /* return number of bytes read */
                             struct connectdata *conn,
                             int *ftpcode) /* return the ftp-code */
{
  /* Brand new implementation.
   * We cannot read just one byte per read() and then go back to select()
   * as it seems that the OpenSSL read() stuff doesn't grok that properly.
   *
   * Alas, read as much as possible, split up into lines, use the ending
   * line in a response or continue reading.  */

  curl_socket_t sockfd = conn->sock[FIRSTSOCKET];
  int perline; /* count bytes per line */
  bool keepon=TRUE;
  ssize_t gotbytes;
  char *ptr;
  long timeout;              /* timeout in seconds */
  int interval_ms;
  struct SessionHandle *data = conn->data;
  char *line_start;
  int code=0; /* default ftp "error code" to return */
  char *buf = data->state.buffer;
  CURLcode result = CURLE_OK;
  struct FTP *ftp = conn->proto.ftp;
  struct timeval now = Curl_tvnow();

  if (ftpcode)
    *ftpcode = 0; /* 0 for errors */

  ptr=buf;
  line_start = buf;

  *nreadp=0;
  perline=0;
  keepon=TRUE;

  while((*nreadp<BUFSIZE) && (keepon && !result)) {
    /* check and reset timeout value every lap */
    if(data->set.ftp_response_timeout )
      /* if CURLOPT_FTP_RESPONSE_TIMEOUT is set, use that to determine
         remaining time.  Also, use "now" as opposed to "conn->now"
         because ftp_response_timeout is only supposed to govern
         the response for any given ftp response, not for the time
         from connect to the given ftp response. */
      timeout = data->set.ftp_response_timeout - /* timeout time */
        Curl_tvdiff(Curl_tvnow(), now)/1000; /* spent time */
    else if(data->set.timeout)
      /* if timeout is requested, find out how much remaining time we have */
      timeout = data->set.timeout - /* timeout time */
        Curl_tvdiff(Curl_tvnow(), conn->now)/1000; /* spent time */
    else
      /* Even without a requested timeout, we only wait response_time
         seconds for the full response to arrive before we bail out */
      timeout = ftp->response_time -
        Curl_tvdiff(Curl_tvnow(), now)/1000; /* spent time */

    if(timeout <=0 ) {
      failf(data, "FTP response timeout");
      return CURLE_OPERATION_TIMEDOUT; /* already too little time */
    }

    if(!ftp->cache) {
      interval_ms = 1 * 1000;  /* use 1 second timeout intervals */

      switch (Curl_select(sockfd, CURL_SOCKET_BAD, interval_ms)) {
      case -1: /* select() error, stop reading */
        result = CURLE_RECV_ERROR;
        failf(data, "FTP response aborted due to select() error: %d", errno);
        break;
      case 0: /* timeout */
        if(Curl_pgrsUpdate(conn))
          return CURLE_ABORTED_BY_CALLBACK;
        continue; /* just continue in our loop for the timeout duration */

      default:
        break;
      }
    }
    if(CURLE_OK == result) {
      /*
       * This code previously didn't use the kerberos sec_read() code
       * to read, but when we use Curl_read() it may do so. Do confirm
       * that this is still ok and then remove this comment!
       */
      if(ftp->cache) {
        /* we had data in the "cache", copy that instead of doing an actual
         * read
         *
         * Dave Meyer, December 2003:
         * ftp->cache_size is cast to int here.  This should be safe,
         * because it would have been populated with something of size
         * int to begin with, even though its datatype may be larger
         * than an int.
         */
        memcpy(ptr, ftp->cache, (int)ftp->cache_size);
        gotbytes = (int)ftp->cache_size;
        free(ftp->cache);    /* free the cache */
        ftp->cache = NULL;   /* clear the pointer */
        ftp->cache_size = 0; /* zero the size just in case */
      }
      else {
        int res = Curl_read(conn, sockfd, ptr, BUFSIZE-*nreadp, &gotbytes);
        if(res < 0)
          /* EWOULDBLOCK */
          continue; /* go looping again */

        if(CURLE_OK != res)
          keepon = FALSE;
      }

      if(!keepon)
        ;
      else if(gotbytes <= 0) {
        keepon = FALSE;
        result = CURLE_RECV_ERROR;
        failf(data, "FTP response reading failed");
      }
      else {
        /* we got a whole chunk of data, which can be anything from one
         * byte to a set of lines and possible just a piece of the last
         * line */
        int i;

        conn->headerbytecount += gotbytes;

        *nreadp += gotbytes;
        for(i = 0; i < gotbytes; ptr++, i++) {
          perline++;
          if(*ptr=='\n') {
            /* a newline is CRLF in ftp-talk, so the CR is ignored as
               the line isn't really terminated until the LF comes */

            /* output debug output if that is requested */
            if(data->set.verbose)
              Curl_debug(data, CURLINFO_HEADER_IN, line_start, perline, conn);

            /*
             * We pass all response-lines to the callback function registered
             * for "headers". The response lines can be seen as a kind of
             * headers.
             */
            result = Curl_client_write(data, CLIENTWRITE_HEADER,
                                       line_start, perline);
            if(result)
              return result;

#define lastline(line) (isdigit((int)line[0]) && isdigit((int)line[1]) && \
                        isdigit((int)line[2]) && (' ' == line[3]))

            if(perline>3 && lastline(line_start)) {
              /* This is the end of the last line, copy the last
               * line to the start of the buffer and zero terminate,
               * for old times sake (and krb4)! */
              char *meow;
              int n;
              for(meow=line_start, n=0; meow<ptr; meow++, n++)
                buf[n] = *meow;
              *meow=0; /* zero terminate */
              keepon=FALSE;
              line_start = ptr+1; /* advance pointer */
              i++; /* skip this before getting out */
              break;
            }
            perline=0; /* line starts over here */
            line_start = ptr+1;
          }
        }
        if(!keepon && (i != gotbytes)) {
          /* We found the end of the response lines, but we didn't parse the
             full chunk of data we have read from the server. We therefore
             need to store the rest of the data to be checked on the next
             invoke as it may actually contain another end of response
             already!  Cleverly figured out by Eric Lavigne in December
             2001. */
          ftp->cache_size = gotbytes - i;
          ftp->cache = (char *)malloc((int)ftp->cache_size);
          if(ftp->cache)
            memcpy(ftp->cache, line_start, (int)ftp->cache_size);
          else
            return CURLE_OUT_OF_MEMORY; /**BANG**/
        }
      } /* there was data */
    } /* if(no error) */
  } /* while there's buffer left and loop is requested */

  if(!result)
    code = atoi(buf);

#ifdef HAVE_KRB4
  /* handle the security-oriented responses 6xx ***/
  /* FIXME: some errorchecking perhaps... ***/
  switch(code) {
  case 631:
    Curl_sec_read_msg(conn, buf, prot_safe);
    break;
  case 632:
    Curl_sec_read_msg(conn, buf, prot_private);
    break;
  case 633:
    Curl_sec_read_msg(conn, buf, prot_confidential);
    break;
  default:
    /* normal ftp stuff we pass through! */
    break;
  }
#endif

  if(ftpcode)
    *ftpcode=code; /* return the initial number like this */

  /* store the latest code for later retrieval */
  conn->data->info.httpcode=code;

  return result;
}

/*
 * Curl_ftp_connect() should do everything that is to be considered a part of
 * the connection phase.
 */
CURLcode Curl_ftp_connect(struct connectdata *conn)
{
  /* this is FTP and no proxy */
  ssize_t nread;
  struct SessionHandle *data=conn->data;
  char *buf = data->state.buffer; /* this is our buffer */
  struct FTP *ftp;
  CURLcode result;
  int ftpcode, trynum;
  static const char * const ftpauth[]  = {
    "SSL", "TLS", NULL
  };

  ftp = (struct FTP *)calloc(sizeof(struct FTP), 1);
  if(!ftp)
    return CURLE_OUT_OF_MEMORY;

  conn->proto.ftp = ftp;

  /* We always support persistant connections on ftp */
  conn->bits.close = FALSE;

  /* get some initial data into the ftp struct */
  ftp->bytecountp = &conn->bytecount;

  /* no need to duplicate them, this connectdata struct won't change */
  ftp->user = conn->user;
  ftp->passwd = conn->passwd;
  if (isBadFtpString(ftp->user) || isBadFtpString(ftp->passwd)) {
    return CURLE_URL_MALFORMAT;
  }
  ftp->response_time = 3600; /* set default response time-out */

#ifndef CURL_DISABLE_HTTP
  if (conn->bits.tunnel_proxy) {
    /* We want "seamless" FTP operations through HTTP proxy tunnel */
    result = Curl_ConnectHTTPProxyTunnel(conn, FIRSTSOCKET,
                                         conn->host.name, conn->remote_port);
    if(CURLE_OK != result)
      return result;
  }
#endif   /* CURL_DISABLE_HTTP */

  if(conn->protocol & PROT_FTPS) {
    /* FTPS is simply ftp with SSL for the control channel */
    /* now, perform the SSL initialization for this socket */
    result = Curl_SSLConnect(conn, FIRSTSOCKET);
    if(result)
      return result;
  }

  /* The first thing we do is wait for the "220*" line: */
  result = Curl_GetFTPResponse(&nread, conn, &ftpcode);
  if(result)
    return result;

  if(ftpcode != 220) {
    failf(data, "This doesn't seem like a nice ftp-server response");
    return CURLE_FTP_WEIRD_SERVER_REPLY;
  }

#ifdef HAVE_KRB4
  /* if not anonymous login, try a secure login */
  if(data->set.krb4) {

    /* request data protection level (default is 'clear') */
    Curl_sec_request_prot(conn, "private");

    /* We set private first as default, in case the line below fails to
       set a valid level */
    Curl_sec_request_prot(conn, data->set.krb4_level);

    if(Curl_sec_login(conn) != 0)
      infof(data, "Logging in with password in cleartext!\n");
    else
      infof(data, "Authentication successful\n");
  }
#endif

  if(data->set.ftp_ssl && !conn->ssl[FIRSTSOCKET].use) {
    /* we don't have a SSL/TLS connection, try a FTPS connection now */
    int start;
    int trynext;
    int count=0;

    switch(data->set.ftpsslauth) {
    case CURLFTPAUTH_DEFAULT:
    case CURLFTPAUTH_SSL:
      start = 0;
      trynext = 1;
      break;
    case CURLFTPAUTH_TLS:
      start = 1;
      trynext = 0;
      break;
    default:
      failf(data, "unsupported parameter to CURLOPT_FTPSSLAUTH: %d\n",
            data->set.ftpsslauth);
      return CURLE_FAILED_INIT; /* we don't know what to do */
    }

    for (trynum = start; ftpauth[count]; trynum=trynext, count++) {

      FTPSENDF(conn, "AUTH %s", ftpauth[trynum]);

      result = Curl_GetFTPResponse(&nread, conn, &ftpcode);

      if(result)
        return result;

      /* RFC2228 (page 5) says:
       *
       * If the server is willing to accept the named security mechanism, and
       * does not require any security data, it must respond with reply code
       * 234/334.
       */

      if((ftpcode == 234) || (ftpcode == 334)) {
        result = Curl_SSLConnect(conn, FIRSTSOCKET);
        if(result)
          return result;
        conn->protocol |= PROT_FTPS;
        conn->ssl[SECONDARYSOCKET].use = FALSE; /* clear-text data */
        break;
      }
    }
  }

  /* send USER */
  FTPSENDF(conn, "USER %s", ftp->user?ftp->user:"");

  /* wait for feedback */
  result = Curl_GetFTPResponse(&nread, conn, &ftpcode);
  if(result)
    return result;

  if(ftpcode == 530) {
    /* 530 User ... access denied
       (the server denies to log the specified user) */
    failf(data, "Access denied: %03d", ftpcode);
    return CURLE_FTP_ACCESS_DENIED;
  }
  else if(ftpcode == 331) {
    /* 331 Password required for ...
       (the server requires to send the user's password too) */
    FTPSENDF(conn, "PASS %s", ftp->passwd?ftp->passwd:"");
    result = Curl_GetFTPResponse(&nread, conn, &ftpcode);
    if(result)
      return result;

    if(ftpcode == 530) {
      /* 530 Login incorrect.
         (the username and/or the password are incorrect)
      or
         530 Sorry, the maximum number of allowed users are already connected
      */
      failf(data, "not logged in: %03d", ftpcode);
      return CURLE_FTP_USER_PASSWORD_INCORRECT;
    }
    else if(ftpcode/100 == 2) {
      /* 230 User ... logged in.
         (user successfully logged in)

         Apparently, proftpd with SSL returns 232 here at times. */

      infof(data, "We have successfully logged in\n");
    }
    else if(ftpcode == 332) {
      /* 332 Please provide account info */
      if(data->set.ftp_account) {
        FTPSENDF(conn, "ACCT %s", data->set.ftp_account);
        result = Curl_GetFTPResponse(&nread, conn, &ftpcode);
        if(!result && (ftpcode != 230)) {
          failf(data, "ACCT rejected by server: %03d", ftpcode);
          result = CURLE_FTP_WEIRD_PASS_REPLY; /* FIX */
        }
      }
      else {
        failf(data, "ACCT requested by none available");
        result = CURLE_FTP_WEIRD_PASS_REPLY;
      }
      if(result)
        return result;
    }
    else {
      failf(data, "Odd return code after PASS");
      return CURLE_FTP_WEIRD_PASS_REPLY;
    }
  }
  else if(buf[0] == '2') {
    /* 230 User ... logged in.
       (the user logged in without password) */
    infof(data, "We have successfully logged in\n");
    if (conn->ssl[FIRSTSOCKET].use) {
#ifdef HAVE_KRB4
      /* We are logged in with Kerberos, now set the requested protection
       * level
       */
      if(conn->sec_complete)
        Curl_sec_set_protection_level(conn);

      /* We may need to issue a KAUTH here to have access to the files
       * do it if user supplied a password
       */
      if(conn->passwd && *conn->passwd) {
        result = Curl_krb_kauth(conn);
        if(result)
          return result;
      }
#endif
    }
  }
  else {
    failf(data, "Odd return code after USER");
    return CURLE_FTP_WEIRD_USER_REPLY;
  }

  if(conn->ssl[FIRSTSOCKET].use) {
    /* PBSZ = PROTECTION BUFFER SIZE.

       The 'draft-murray-auth-ftp-ssl' (draft 12, page 7) says:

       Specifically, the PROT command MUST be preceded by a PBSZ command
       and a PBSZ command MUST be preceded by a successful security data
       exchange (the TLS negotiation in this case)

       ... (and on page 8):

       Thus the PBSZ command must still be issued, but must have a parameter
       of '0' to indicate that no buffering is taking place and the data
       connection should not be encapsulated.
    */
    FTPSENDF(conn, "PBSZ %d", 0);
    result = Curl_GetFTPResponse(&nread, conn, &ftpcode);
    if(result)
      return result;

    /* For TLS, the data connection can have one of two security levels.

       1)Clear (requested by 'PROT C')

       2)Private (requested by 'PROT P')
    */
    if(!conn->ssl[SECONDARYSOCKET].use) {
      FTPSENDF(conn, "PROT %c", 'P');
      result = Curl_GetFTPResponse(&nread, conn, &ftpcode);
      if(result)
        return result;

      if(ftpcode/100 == 2)
        /* We have enabled SSL for the data connection! */
        conn->ssl[SECONDARYSOCKET].use = TRUE;
      /* FTP servers typically responds with 500 if they decide to reject
         our 'P' request */
      else if(data->set.ftp_ssl> CURLFTPSSL_CONTROL)
        /* we failed and bails out */
        return CURLE_FTP_SSL_FAILED;
    }
  }

  /* send PWD to discover our entry point */
  FTPSENDF(conn, "PWD", NULL);

  /* wait for feedback */
  result = Curl_GetFTPResponse(&nread, conn, &ftpcode);
  if(result)
    return result;

  if(ftpcode == 257) {
    char *dir = (char *)malloc(nread+1);
    char *store=dir;
    char *ptr=&buf[4]; /* start on the first letter */

    if(!dir)
      return CURLE_OUT_OF_MEMORY;

    /* Reply format is like
       257<space>"<directory-name>"<space><commentary> and the RFC959 says

       The directory name can contain any character; embedded double-quotes
       should be escaped by double-quotes (the "quote-doubling" convention).
    */
    if('\"' == *ptr) {
      /* it started good */
      ptr++;
      while(ptr && *ptr) {
        if('\"' == *ptr) {
          if('\"' == ptr[1]) {
            /* "quote-doubling" */
            *store = ptr[1];
            ptr++;
          }
          else {
            /* end of path */
            *store = '\0'; /* zero terminate */
            break; /* get out of this loop */
          }
        }
        else
          *store = *ptr;
        store++;
        ptr++;
      }
      ftp->entrypath =dir; /* remember this */
      infof(data, "Entry path is '%s'\n", ftp->entrypath);
    }
    else {
      /* couldn't get the path */
      free(dir);
      infof(data, "Failed to figure out path\n");
    }

  }
  else {
    /* We couldn't read the PWD response! */
  }

  return CURLE_OK;
}

/***********************************************************************
 *
 * Curl_ftp_done()
 *
 * The DONE function. This does what needs to be done after a single DO has
 * performed.
 *
 * Input argument is already checked for validity.
 */
CURLcode Curl_ftp_done(struct connectdata *conn, CURLcode status)
{
  struct SessionHandle *data = conn->data;
  struct FTP *ftp = conn->proto.ftp;
  ssize_t nread;
  int ftpcode;
  CURLcode result=CURLE_OK;
  bool was_ctl_valid = ftp->ctl_valid;
  size_t flen;
  size_t dlen;
  char *path;

  /* now store a copy of the directory we are in */
  if(ftp->prevpath)
    free(ftp->prevpath);

  path = curl_unescape(conn->path, 0); /* get the "raw" path */
  if(!path)
    return CURLE_OUT_OF_MEMORY;

  flen = ftp->file?strlen(ftp->file):0; /* file is "raw" already */
  dlen = strlen(path)-flen;
  if(dlen) {
    ftp->prevpath = path;
    if(flen)
      /* if 'path' is not the whole string */
      ftp->prevpath[dlen]=0; /* terminate */
    infof(data, "Remembering we are in dir %s\n", ftp->prevpath);
  }
  else {
    ftp->prevpath = NULL; /* no path */
    free(path);
  }
  /* free the dir tree and file parts */
  freedirs(ftp);

  ftp->ctl_valid = FALSE;

  if(data->set.upload) {
    if((-1 != data->set.infilesize) &&
       (data->set.infilesize != *ftp->bytecountp) &&
       !data->set.crlf) {
      failf(data, "Uploaded unaligned file size (%" FORMAT_OFF_T
            " out of %" FORMAT_OFF_T " bytes)",
            *ftp->bytecountp, data->set.infilesize);
      conn->bits.close = TRUE; /* close this connection since we don't
                                  know what state this error leaves us in */
      return CURLE_PARTIAL_FILE;
    }
  }
  else {
    if((-1 != conn->size) && (conn->size != *ftp->bytecountp) &&
       (conn->maxdownload != *ftp->bytecountp)) {
      failf(data, "Received only partial file: %" FORMAT_OFF_T " bytes",
            *ftp->bytecountp);
      conn->bits.close = TRUE; /* close this connection since we don't
                                  know what state this error leaves us in */
      return CURLE_PARTIAL_FILE;
    }
    else if(!ftp->dont_check &&
            !*ftp->bytecountp &&
            (conn->size>0)) {
      /* We consider this an error, but there's no true FTP error received
         why we need to continue to "read out" the server response too.
         We don't want to leave a "waiting" server reply if we'll get told
         to make a second request on this same connection! */
      failf(data, "No data was received!");
      result = CURLE_FTP_COULDNT_RETR_FILE;
    }
  }

  switch(status) {
  case CURLE_BAD_DOWNLOAD_RESUME:
  case CURLE_FTP_WEIRD_PASV_REPLY:
  case CURLE_FTP_PORT_FAILED:
  case CURLE_FTP_COULDNT_SET_BINARY:
  case CURLE_FTP_COULDNT_RETR_FILE:
  case CURLE_FTP_ACCESS_DENIED:
    /* the connection stays alive fine even though this happened */
    /* fall-through */
  case CURLE_OK: /* doesn't affect the control connection's status */
    ftp->ctl_valid = was_ctl_valid;
    break;
  default:       /* by default, an error means the control connection is
                    wedged and should not be used anymore */
    ftp->ctl_valid = FALSE;
    break;
  }

#ifdef HAVE_KRB4
  Curl_sec_fflush_fd(conn, conn->sock[SECONDARYSOCKET]);
#endif

  /* shut down the socket to inform the server we're done */

#ifdef _WIN32_WCE
  shutdown(conn->sock[SECONDARYSOCKET],2);  /* SD_BOTH */
#endif

  sclose(conn->sock[SECONDARYSOCKET]);

  conn->sock[SECONDARYSOCKET] = CURL_SOCKET_BAD;

  if(!ftp->no_transfer && !status) {
    /* Let's see what the server says about the transfer we just performed,
     * but lower the timeout as sometimes this connection has died while the
     * data has been transfered. This happens when doing through NATs etc that
     * abandon old silent connections.
     */
    ftp->response_time = 60; /* give it only a minute for now */

    result = Curl_GetFTPResponse(&nread, conn, &ftpcode);

    ftp->response_time = 3600; /* set this back to one hour waits */

    if(!nread && (CURLE_OPERATION_TIMEDOUT == result)) {
      failf(data, "control connection looks dead");
      return result;
    }

    if(result)
      return result;

    if(!ftp->dont_check) {
      /* 226 Transfer complete, 250 Requested file action okay, completed. */
      if((ftpcode != 226) && (ftpcode != 250)) {
        failf(data, "server did not report OK, got %d", ftpcode);
        return CURLE_FTP_WRITE_ERROR;
      }
    }
  }

  /* clear these for next connection */
  ftp->no_transfer = FALSE;
  ftp->dont_check = FALSE;

  if (!result && conn->sec_conn) {   /* 3rd party transfer */
    /* "done" with the secondary connection */
    result = Curl_ftp_done(conn->sec_conn, status);
  }

  /* Send any post-transfer QUOTE strings? */
  if(!status && !result && data->set.postquote)
    result = ftp_sendquote(conn, data->set.postquote);

  return result;
}

/***********************************************************************
 *
 * ftp_sendquote()
 *
 * Where a 'quote' means a list of custom commands to send to the server.
 * The quote list is passed as an argument.
 */

static
CURLcode ftp_sendquote(struct connectdata *conn, struct curl_slist *quote)
{
  struct curl_slist *item;
  ssize_t nread;
  int ftpcode;
  CURLcode result;

  item = quote;
  while (item) {
    if (item->data) {
      FTPSENDF(conn, "%s", item->data);

      result = Curl_GetFTPResponse(&nread, conn, &ftpcode);
      if (result)
        return result;

      if (ftpcode >= 400) {
        failf(conn->data, "QUOT string not accepted: %s", item->data);
        return CURLE_FTP_QUOTE_ERROR;
      }
    }

    item = item->next;
  }

  return CURLE_OK;
}

/***********************************************************************
 *
 * ftp_getfiletime()
 *
 * Get the timestamp of the given file.
 */
static
CURLcode ftp_getfiletime(struct connectdata *conn, char *file)
{
  CURLcode result=CURLE_OK;
  int ftpcode; /* for ftp status */
  ssize_t nread;
  char *buf = conn->data->state.buffer;

  /* we have requested to get the modified-time of the file, this is yet
     again a grey area as the MDTM is not kosher RFC959 */
  FTPSENDF(conn, "MDTM %s", file);

  result = Curl_GetFTPResponse(&nread, conn, &ftpcode);
  if(result)
    return result;

  switch(ftpcode) {
  case 213:
    {
      /* we got a time. Format should be: "YYYYMMDDHHMMSS[.sss]" where the
         last .sss part is optional and means fractions of a second */
      int year, month, day, hour, minute, second;
      if(6 == sscanf(buf+4, "%04d%02d%02d%02d%02d%02d",
                     &year, &month, &day, &hour, &minute, &second)) {