ssh.c

  /*
   * At this point we have an authenticated ssh session.
   */
  infof(conn->data, "Authentication complete\n");

  conn->sockfd = sock;
  conn->writesockfd = CURL_SOCKET_BAD;

  if (conn->protocol == PROT_SFTP) {
    /*
     * Start the libssh2 sftp session
     */
    ssh->sftp_session = libssh2_sftp_init(ssh->ssh_session);
    if (ssh->sftp_session == NULL) {
      failf(data, "Failure initialising sftp session\n");
      libssh2_session_free(ssh->ssh_session);
      ssh->ssh_session = NULL;
      return CURLE_FAILED_INIT;
    }

    /*
     * Get the "home" directory
     */
    i = libssh2_sftp_realpath(ssh->sftp_session, ".", tempHome, PATH_MAX-1);
    if (i > 0) {
      /* It seems that this string is not always NULL terminated */
      tempHome[i] = '\0';
      ssh->homedir = (char *)strdup(tempHome);
      if (!ssh->homedir) {
        libssh2_sftp_shutdown(ssh->sftp_session);
        ssh->sftp_session = NULL;
        libssh2_session_free(ssh->ssh_session);
        ssh->ssh_session = NULL;
        return CURLE_OUT_OF_MEMORY;
      }
    }
    else {
      /* Return the error type */
      i = libssh2_sftp_last_error(ssh->sftp_session);
      DEBUGF(infof(data, "error = %d\n", i));
    }
  }

  working_path = curl_easy_unescape(data, data->reqdata.path, 0,
                                    &working_path_len);
  if (!working_path)
    return CURLE_OUT_OF_MEMORY;

  /* Check for /~/ , indicating relative to the user's home directory */
  if (conn->protocol == PROT_SCP) {
    real_path = (char *)malloc(working_path_len+1);
    if (real_path == NULL) {
      libssh2_session_free(ssh->ssh_session);
      ssh->ssh_session = NULL;
      Curl_safefree(working_path);
      return CURLE_OUT_OF_MEMORY;
    }
    if (working_path[1] == '~')
      /* It is referenced to the home directory, so strip the leading '/' */
      memcpy(real_path, working_path+1, 1 + working_path_len-1);
    else
      memcpy(real_path, working_path, 1 + working_path_len);
  }
  else if (conn->protocol == PROT_SFTP) {
    if (working_path[1] == '~') {
      real_path = (char *)malloc(strlen(ssh->homedir) +
                                 working_path_len + 1);
      if (real_path == NULL) {
        libssh2_sftp_shutdown(ssh->sftp_session);
        ssh->sftp_session = NULL;
        libssh2_session_free(ssh->ssh_session);
        ssh->ssh_session = NULL;
        Curl_safefree(ssh->homedir);
        ssh->homedir = NULL;
        Curl_safefree(working_path);
        return CURLE_OUT_OF_MEMORY;
      }
      /* It is referenced to the home directory, so strip the leading '/' */
      memcpy(real_path, ssh->homedir, strlen(ssh->homedir));
      real_path[strlen(ssh->homedir)] = '/';
      real_path[strlen(ssh->homedir)+1] = '\0';
      if (working_path_len > 3) {
        memcpy(real_path+strlen(ssh->homedir)+1, working_path + 3,
               1 + working_path_len -3);
      }
    }
    else {
      real_path = (char *)malloc(working_path_len+1);
      if (real_path == NULL) {
        libssh2_sftp_shutdown(ssh->sftp_session);
        ssh->sftp_session = NULL;
        libssh2_session_free(ssh->ssh_session);
        ssh->ssh_session = NULL;
        Curl_safefree(ssh->homedir);
        ssh->homedir = NULL;
        Curl_safefree(working_path);
        return CURLE_OUT_OF_MEMORY;
      }
      memcpy(real_path, working_path, 1+working_path_len);
    }
  }
  else {
    libssh2_session_free(ssh->ssh_session);
    ssh->ssh_session = NULL;
    Curl_safefree(working_path);
    return CURLE_FAILED_INIT;
  }

  Curl_safefree(working_path);
  ssh->path = real_path;

  *done = TRUE;
  return CURLE_OK;
#endif /* !(LIBSSH2_APINO >= 200706012030) */
}

CURLcode Curl_scp_do(struct connectdata *conn, bool *done)
{
  struct stat sb;
  struct SSHPROTO *scp = conn->data->reqdata.proto.ssh;
  CURLcode res = CURLE_OK;

  *done = TRUE; /* unconditionally */

  if (conn->data->set.upload) {
    if(conn->data->set.infilesize < 0) {
      failf(conn->data, "SCP requires a known file size for upload");
      return CURLE_UPLOAD_FAILED;
    }
    /*
     * libssh2 requires that the destination path is a full path that includes
     * the destination file and name OR ends in a "/" .  If this is not done
     * the destination file will be named the same name as the last directory
     * in the path.
     */
#if (LIBSSH2_APINO >= 200706012030)
    do {
      scp->ssh_channel = libssh2_scp_send_ex(scp->ssh_session, scp->path,
                                             conn->data->set.new_file_perms,
                                             conn->data->set.infilesize, 0, 0);
      if (!scp->ssh_channel &&
          (libssh2_session_last_errno(scp->ssh_session) !=
           LIBSSH2_ERROR_EAGAIN)) {
        int err;
        char *err_msg;

        err = libssh2_session_error_to_CURLE(
            libssh2_session_last_error(scp->ssh_session, &err_msg, NULL, 0));
        failf(conn->data, "%s", err_msg);
        return err;
      }
    } while (!scp->ssh_channel);
#else /* !(LIBSSH2_APINO >= 200706012030) */
    scp->ssh_channel = libssh2_scp_send_ex(scp->ssh_session, scp->path,
                                           conn->data->set.new_file_perms,
                                           conn->data->set.infilesize, 0, 0);
    if (!scp->ssh_channel)
      return CURLE_FAILED_INIT;
#endif /* !(LIBSSH2_APINO >= 200706012030) */

    /* upload data */
    res = Curl_setup_transfer(conn, -1, -1, FALSE, NULL, FIRSTSOCKET, NULL);
  }
  else {
    /*
     * We must check the remote file; if it is a directory no values will
     * be set in sb
     */
    curl_off_t bytecount;
    memset(&sb, 0, sizeof(struct stat));
#if (LIBSSH2_APINO >= 200706012030)
    do {
      scp->ssh_channel = libssh2_scp_recv(scp->ssh_session, scp->path, &sb);
      if (!scp->ssh_channel &&
          (libssh2_session_last_errno(scp->ssh_session) !=
           LIBSSH2_ERROR_EAGAIN)) {
        if ((sb.st_mode == 0) && (sb.st_atime == 0) && (sb.st_mtime == 0) &&
            (sb.st_size == 0)) {
          /* Since sb is still empty, it is likely the file was not found */
          return CURLE_REMOTE_FILE_NOT_FOUND;
        }
        return libssh2_session_error_to_CURLE(
          libssh2_session_last_error(scp->ssh_session, NULL, NULL, 0));
      }
    } while (!scp->ssh_channel);
#else /* !(LIBSSH2_APINO >= 200706012030) */
    scp->ssh_channel = libssh2_scp_recv(scp->ssh_session, scp->path, &sb);
    if (!scp->ssh_channel) {
      if ((sb.st_mode == 0) && (sb.st_atime == 0) && (sb.st_mtime == 0) &&
          (sb.st_size == 0)) {
        /* Since sb is still empty, it is likely the file was not found */
        return CURLE_REMOTE_FILE_NOT_FOUND;
      }
      return libssh2_session_error_to_CURLE(
        libssh2_session_last_error(scp->ssh_session, NULL, NULL, 0));
    }
#endif /* !(LIBSSH2_APINO >= 200706012030) */
    /* download data */
    bytecount = (curl_off_t) sb.st_size;
    conn->data->reqdata.maxdownload =  (curl_off_t) sb.st_size;
    res = Curl_setup_transfer(conn, FIRSTSOCKET,
                              bytecount, FALSE, NULL, -1, NULL);
  }

  return res;
}

CURLcode Curl_scp_done(struct connectdata *conn, CURLcode status,
                       bool premature)
{
  int rc;
  struct SSHPROTO *scp = conn->data->reqdata.proto.ssh;
  (void)premature; /* not used */

  Curl_safefree(scp->path);
  scp->path = NULL;

  if (scp->ssh_channel) {
#if (LIBSSH2_APINO >= 200706012030)
    if (conn->data->set.upload) {
      while ((rc = libssh2_channel_send_eof(scp->ssh_channel)) ==
             LIBSSH2_ERROR_EAGAIN);
      if (rc) {
        infof(conn->data, "Failed to send libssh2 channel EOF\n");
      }
      while ((rc = libssh2_channel_wait_eof(scp->ssh_channel)) ==
             LIBSSH2_ERROR_EAGAIN);
      if (rc) {
        infof(conn->data, "Failed to get channel EOF\n");
      }
      while ((rc = libssh2_channel_wait_closed(scp->ssh_channel)) ==
             LIBSSH2_ERROR_EAGAIN);
      if (rc) {
        infof(conn->data, "Channel failed to close\n");
      }
    }
#else /* !(LIBSSH2_APINO >= 200706012030) */
    if (conn->data->set.upload &&
        libssh2_channel_send_eof(scp->ssh_channel) < 0) {
      infof(conn->data, "Failed to send libssh2 channel EOF\n");
    }
    if (libssh2_channel_close(scp->ssh_channel) < 0) {
      infof(conn->data, "Failed to stop libssh2 channel subsystem\n");
    }
#endif /* !(LIBSSH2_APINO >= 200706012030) */
    libssh2_channel_free(scp->ssh_channel);
  }

  if (scp->ssh_session) {
#if (LIBSSH2_APINO >= 200706012030)
    while (libssh2_session_disconnect(scp->ssh_session, "Shutdown") ==
           LIBSSH2_ERROR_EAGAIN);
#else /* !(LIBSSH2_APINO >= 200706012030) */
    libssh2_session_disconnect(scp->ssh_session, "Shutdown");
#endif /* !(LIBSSH2_APINO >= 200706012030) */
    libssh2_session_free(scp->ssh_session);
    scp->ssh_session = NULL;
  }

  free(conn->data->reqdata.proto.ssh);
  conn->data->reqdata.proto.ssh = NULL;
  Curl_pgrsDone(conn);

  (void)status; /* unused */
  (void) rc;    /* possiby unused */

  return CURLE_OK;
}

/* return number of received (decrypted) bytes */
ssize_t Curl_scp_send(struct connectdata *conn, int sockindex,
                      void *mem, size_t len)
{
  ssize_t nwrite;

  /* libssh2_channel_write() returns int
   *
   * NOTE: we should not store nor rely on connection-related data to be
   * in the SessionHandle struct
   */
#if defined(LIBSSH2CHANNEL_EAGAIN) && (LIBSSH2_APINO < 200706012030)
  nwrite = (ssize_t)
    libssh2_channel_writenb(conn->data->reqdata.proto.ssh->ssh_channel,
                            mem, len);
#else
  nwrite = (ssize_t)
    libssh2_channel_write(conn->data->reqdata.proto.ssh->ssh_channel,
                          mem, len);
#if (LIBSSH2_APINO >= 200706012030)
  if (nwrite == LIBSSH2_ERROR_EAGAIN) {
    return 0;
  }
#endif
#endif
  (void)sockindex;
  return nwrite;
}

/*
 * If the read would block (EWOULDBLOCK) we return -1. Otherwise we return
 * a regular CURLcode value.
 */
ssize_t Curl_scp_recv(struct connectdata *conn, int sockindex,
                      char *mem, size_t len)
{
  ssize_t nread;
  (void)sockindex; /* we only support SCP on the fixed known primary socket */

  /* libssh2_channel_read() returns int
   *
   * NOTE: we should not store nor rely on connection-related data to be
   * in the SessionHandle struct
   */

#if defined(LIBSSH2CHANNEL_EAGAIN) && (LIBSSH2_APINO < 200706012030)
  /* we prefer the non-blocking API but that didn't exist previously */
  nread = (ssize_t)
    libssh2_channel_readnb(conn->data->reqdata.proto.ssh->ssh_channel,
                           mem, len);
#else
  nread = (ssize_t)
    libssh2_channel_read(conn->data->reqdata.proto.ssh->ssh_channel,
                         mem, len);
#endif
  return nread;
}

/*
 * =============== SFTP ===============
 */

CURLcode Curl_sftp_do(struct connectdata *conn, bool *done)
{
  LIBSSH2_SFTP_ATTRIBUTES attrs;
  struct SSHPROTO *sftp = conn->data->reqdata.proto.ssh;
  CURLcode res = CURLE_OK;
  struct SessionHandle *data = conn->data;
  curl_off_t bytecount = 0;
  char *buf = data->state.buffer;
  unsigned long err = 0;
  int rc;

  *done = TRUE; /* unconditionally */

  /* Send any quote commands */
  if(conn->data->set.quote) {
    infof(conn->data, "Sending quote commands\n");
    res = sftp_sendquote(conn, conn->data->set.quote);
    if (res != CURLE_OK)
      return res;
  }

  if (data->set.upload) {
    /*
     * NOTE!!!  libssh2 requires that the destination path is a full path
     *          that includes the destination file and name OR ends in a "/" .
     *          If this is not done the destination file will be named the
     *          same name as the last directory in the path.
     */
#if (LIBSSH2_APINO >= 200706012030)
    do {
      sftp->sftp_handle =
        libssh2_sftp_open(sftp->sftp_session, sftp->path,
                        LIBSSH2_FXF_WRITE|LIBSSH2_FXF_CREAT|LIBSSH2_FXF_TRUNC,
                        data->set.new_file_perms);
      if (!sftp->sftp_handle &&
          (libssh2_session_last_errno(sftp->ssh_session) !=
           LIBSSH2_ERROR_EAGAIN)) {
        err = libssh2_sftp_last_error(sftp->sftp_session);
        if (((err == LIBSSH2_FX_NO_SUCH_FILE) ||
             (err == LIBSSH2_FX_FAILURE) ||
             (err == LIBSSH2_FX_NO_SUCH_PATH)) &&
            (conn->data->set.ftp_create_missing_dirs &&
             (strlen(sftp->path) > 1))) {
          /* try to create the path remotely */
          res = sftp_create_dirs(conn);
          if (res == 0) {
            do {
              sftp->sftp_handle = libssh2_sftp_open(sftp->sftp_session,
                          sftp->path,
                          LIBSSH2_FXF_WRITE|LIBSSH2_FXF_CREAT|LIBSSH2_FXF_TRUNC,
                          data->set.new_file_perms);
              if (!sftp->sftp_handle &&
                  (libssh2_session_last_errno(sftp->ssh_session) !=
                   LIBSSH2_ERROR_EAGAIN)) {
                err = libssh2_sftp_last_error(sftp->sftp_session);
                failf(conn->data, "Could not open remote file for writing: %s",
                      sftp_libssh2_strerror(err));
                return sftp_libssh2_error_to_CURLE(err);
              }
            } while (!sftp->sftp_handle);
          }
        }
        if (!sftp->sftp_handle) {
          err = libssh2_sftp_last_error(sftp->sftp_session);
          failf(conn->data, "Could not open remote file for writing: %s",
                sftp_libssh2_strerror(err));
          return sftp_libssh2_error_to_CURLE(err);
        }
      }
    } while (!sftp->sftp_handle);
#else /* !(LIBSSH2_APINO >= 200706012030) */
    sftp->sftp_handle =
      libssh2_sftp_open(sftp->sftp_session, sftp->path,
                        LIBSSH2_FXF_WRITE|LIBSSH2_FXF_CREAT|LIBSSH2_FXF_TRUNC,
                        data->set.new_file_perms);
    if (!sftp->sftp_handle) {
      err = libssh2_sftp_last_error(sftp->sftp_session);
      if (((err == LIBSSH2_FX_NO_SUCH_FILE) ||
          (err == LIBSSH2_FX_FAILURE) ||
          (err == LIBSSH2_FX_NO_SUCH_PATH)) &&
          (conn->data->set.ftp_create_missing_dirs &&
           (strlen(sftp->path) > 1))) {
        /* try to create the path remotely */
        res = sftp_create_dirs(conn);
        if (res == 0) {
          sftp->sftp_handle = libssh2_sftp_open(sftp->sftp_session, sftp->path,
                    LIBSSH2_FXF_WRITE|LIBSSH2_FXF_CREAT|LIBSSH2_FXF_TRUNC,
                    data->set.new_file_perms);
        }
      }
      if (!sftp->sftp_handle) {
        err = libssh2_sftp_last_error(sftp->sftp_session);
        failf(conn->data, "Could not open remote file for writing: %s",
              sftp_libssh2_strerror(err));
        return sftp_libssh2_error_to_CURLE(err);
      }
    }
#endif /* !(LIBSSH2_APINO >= 200706012030) */

    /* upload data */
    res = Curl_setup_transfer(conn, -1, -1, FALSE, NULL, FIRSTSOCKET, NULL);
  }
  else {
    if (sftp->path[strlen(sftp->path)-1] == '/') {
      /*
       * This is a directory that we are trying to get, so produce a
       * directory listing
       *
       * **BLOCKING behaviour** This should be made into a state machine and
       * get a separate function called from Curl_sftp_recv() when there is
       * data to read from the network, instead of "hanging" here.
       */
      char filename[PATH_MAX+1];
      int len, totalLen, currLen;
      char *line;

#if (LIBSSH2_APINO >= 200706012030)
      do {
        sftp->sftp_handle =
          libssh2_sftp_opendir(sftp->sftp_session, sftp->path);
        if (!sftp->sftp_handle &&
            (libssh2_session_last_errno(sftp->ssh_session) !=
             LIBSSH2_ERROR_EAGAIN)) {
          err = libssh2_sftp_last_error(sftp->sftp_session);
          failf(conn->data, "Could not open directory for reading: %s",
                sftp_libssh2_strerror(err));
          return sftp_libssh2_error_to_CURLE(err);
        }
      } while (!sftp->sftp_handle);
#else /* !(LIBSSH2_APINO >= 200706012030) */
      sftp->sftp_handle =
        libssh2_sftp_opendir(sftp->sftp_session, sftp->path);
      if (!sftp->sftp_handle) {
        err = libssh2_sftp_last_error(sftp->sftp_session);
        failf(conn->data, "Could not open directory for reading: %s",
            sftp_libssh2_strerror(err));
        return sftp_libssh2_error_to_CURLE(err);
      }
#endif /* !(LIBSSH2_APINO >= 200706012030) */

      do {
#if (LIBSSH2_APINO >= 200706012030)
        while ((len = libssh2_sftp_readdir(sftp->sftp_handle, filename,
                                           PATH_MAX, &attrs)) ==
               LIBSSH2_ERROR_EAGAIN);
#else /* !(LIBSSH2_APINO >= 200706012030) */
        len = libssh2_sftp_readdir(sftp->sftp_handle, filename,
                                   PATH_MAX, &attrs);
#endif /* !(LIBSSH2_APINO >= 200706012030) */
        if (len > 0) {
          filename[len] = '\0';

          if (data->set.ftp_list_only) {
            char *tmpLine;

            tmpLine = aprintf("%s\n", filename);
            if (tmpLine == NULL) {
              return CURLE_OUT_OF_MEMORY;
            }
            res = Curl_client_write(conn, CLIENTWRITE_BODY, tmpLine, 0);
            Curl_safefree(tmpLine);
          }
          else {
            totalLen = 80 + len;
            line = (char *)malloc(totalLen);
            if (!line)
              return CURLE_OUT_OF_MEMORY;

            if (!(attrs.flags & LIBSSH2_SFTP_ATTR_UIDGID))
              attrs.uid = attrs.gid =0;

            currLen = snprintf(line, totalLen, "----------   1 %5d %5d",
                               attrs.uid, attrs.gid);

            if (attrs.flags & LIBSSH2_SFTP_ATTR_PERMISSIONS) {
              if ((attrs.permissions & LIBSSH2_SFTP_S_IFMT) ==
                  LIBSSH2_SFTP_S_IFDIR) {
                line[0] = 'd';
              }
              else if ((attrs.permissions & LIBSSH2_SFTP_S_IFMT) ==
                       LIBSSH2_SFTP_S_IFLNK) {
                line[0] = 'l';
              }
              else if ((attrs.permissions & LIBSSH2_SFTP_S_IFMT) ==
                       LIBSSH2_SFTP_S_IFSOCK) {
                line[0] = 's';
              }
              else if ((attrs.permissions & LIBSSH2_SFTP_S_IFMT) ==
                       LIBSSH2_SFTP_S_IFCHR) {
                line[0] = 'c';
              }
              else if ((attrs.permissions & LIBSSH2_SFTP_S_IFMT) ==
                       LIBSSH2_SFTP_S_IFBLK) {
                line[0] = 'b';
              }
              if (attrs.permissions & LIBSSH2_SFTP_S_IRUSR) {
                line[1] = 'r';
              }
              if (attrs.permissions & LIBSSH2_SFTP_S_IWUSR) {
                line[2] = 'w';
              }
              if (attrs.permissions & LIBSSH2_SFTP_S_IXUSR) {
                line[3] = 'x';
              }
              if (attrs.permissions & LIBSSH2_SFTP_S_IRGRP) {
                line[4] = 'r';
              }
              if (attrs.permissions & LIBSSH2_SFTP_S_IWGRP) {
                line[5] = 'w';
              }
              if (attrs.permissions & LIBSSH2_SFTP_S_IXGRP) {
                line[6] = 'x';
              }
              if (attrs.permissions & LIBSSH2_SFTP_S_IROTH) {
                line[7] = 'r';
              }
              if (attrs.permissions & LIBSSH2_SFTP_S_IWOTH) {
                line[8] = 'w';
              }
              if (attrs.permissions & LIBSSH2_SFTP_S_IXOTH) {
                line[9] = 'x';
              }
            }
            if (attrs.flags & LIBSSH2_SFTP_ATTR_SIZE) {
              currLen += snprintf(line+currLen, totalLen-currLen, "%11lld",
                                  attrs.filesize);
            }
            if (attrs.flags & LIBSSH2_SFTP_ATTR_ACMODTIME) {
              static const char * const months[12] = {
                "Jan", "Feb", "Mar", "Apr", "May", "Jun",
                "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"};
              struct tm *nowParts;
              time_t now, remoteTime;

              now = time(NULL);
              remoteTime = (time_t)attrs.mtime;
              nowParts = localtime(&remoteTime);

              if ((time_t)attrs.mtime > (now - (3600 * 24 * 180))) {
                currLen += snprintf(line+currLen, totalLen-currLen,
                                    " %s %2d %2d:%02d",
                                    months[nowParts->tm_mon],
                                    nowParts->tm_mday, nowParts->tm_hour,
                                    nowParts->tm_min);
              }
              else {
                currLen += snprintf(line+currLen, totalLen-currLen,
                                    " %s %2d %5d", months[nowParts->tm_mon],
                                    nowParts->tm_mday, 1900+nowParts->tm_year);
              }
            }
            currLen += snprintf(line+currLen, totalLen-currLen, " %s",
                                filename);
            if ((attrs.flags & LIBSSH2_SFTP_ATTR_PERMISSIONS) &&
                ((attrs.permissions & LIBSSH2_SFTP_S_IFMT) ==
                 LIBSSH2_SFTP_S_IFLNK)) {
              char linkPath[PATH_MAX + 1];

              snprintf(linkPath, PATH_MAX, "%s%s", sftp->path, filename);
#if (LIBSSH2_APINO >= 200706012030)
              while ((len = libssh2_sftp_readlink(sftp->sftp_session, linkPath,
                                                  filename, PATH_MAX)) ==
                     LIBSSH2_ERROR_EAGAIN);
#else /* !(LIBSSH2_APINO >= 200706012030) */
              len = libssh2_sftp_readlink(sftp->sftp_session, linkPath,
                                          filename, PATH_MAX);
#endif /* !(LIBSSH2_APINO >= 200706012030) */
              line = realloc(line, totalLen + 4 + len);
              if (!line)
                return CURLE_OUT_OF_MEMORY;

              currLen += snprintf(line+currLen, totalLen-currLen, " -> %s",
                                  filename);
            }

            currLen += snprintf(line+currLen, totalLen-currLen, "\n");
            res = Curl_client_write(conn, CLIENTWRITE_BODY, line, 0);
            free(line);
          }
        }
        else if (len <= 0) {
          break;
        }
      } while (1);
#if (LIBSSH2_APINO >= 200706012030)
      while (libssh2_sftp_closedir(sftp->sftp_handle) == LIBSSH2_ERROR_EAGAIN);
#else /* !(LIBSSH2_APINO >= 200706012030) */
      libssh2_sftp_closedir(sftp->sftp_handle);
#endif /* !(LIBSSH2_APINO >= 200706012030) */
      sftp->sftp_handle = NULL;

      /* no data to transfer */
      res = Curl_setup_transfer(conn, -1, -1, FALSE, NULL, -1, NULL);
    }
    else {
      /*
       * Work on getting the specified file
       */
#if (LIBSSH2_APINO >= 200706012030)
      do {
        sftp->sftp_handle =
          libssh2_sftp_open(sftp->sftp_session, sftp->path, LIBSSH2_FXF_READ,
                          data->set.new_file_perms);
        if (!sftp->sftp_handle &&
            (libssh2_session_last_errno(sftp->ssh_session) !=
                                   LIBSSH2_ERROR_EAGAIN)) {
          err = libssh2_sftp_last_error(sftp->sftp_session);
          failf(conn->data, "Could not open remote file for reading: %s",
                sftp_libssh2_strerror(err));
          return sftp_libssh2_error_to_CURLE(err);
        }
      } while (!sftp->sftp_handle);
#else /* !(LIBSSH2_APINO >= 200706012030) */
      sftp->sftp_handle =
        libssh2_sftp_open(sftp->sftp_session, sftp->path, LIBSSH2_FXF_READ,
                          data->set.new_file_perms);
      if (!sftp->sftp_handle) {
        err = libssh2_sftp_last_error(sftp->sftp_session);
        failf(conn->data, "Could not open remote file for reading: %s",
            sftp_libssh2_strerror(err));
        return sftp_libssh2_error_to_CURLE(err);
      }
#endif /* !(LIBSSH2_APINO >= 200706012030) */

#if (LIBSSH2_APINO >= 200706012030)
      while ((rc = libssh2_sftp_stat(sftp->sftp_session, sftp->path, &attrs))
             == LIBSSH2_ERROR_EAGAIN);
#else /* !(LIBSSH2_APINO >= 200706012030) */
      rc = libssh2_sftp_stat(sftp->sftp_session, sftp->path, &attrs);
#endif /* !(LIBSSH2_APINO >= 200706012030) */
      if (rc) {
        /*
         * libssh2_sftp_open() didn't return an error, so maybe the server
         * just doesn't support stat()
         */
        data->reqdata.size = -1;
        data->reqdata.maxdownload = -1;
      }
      else {
        data->reqdata.size = attrs.filesize;
        data->reqdata.maxdownload = attrs.filesize;
        Curl_pgrsSetDownloadSize(data, attrs.filesize);
      }

      Curl_pgrsTime(data, TIMER_STARTTRANSFER);

      /* Now download data. The libssh2 0.14 doesn't offer any way to do this
         without using this BLOCKING approach, so here's room for improvement
         once libssh2 can return EWOULDBLOCK to us. */
#if 0
      /* code left here just because this is what this function will use the
         day libssh2 is improved */
      res = Curl_setup_transfer(conn, FIRSTSOCKET,
                                bytecount, FALSE, NULL, -1, NULL);
#endif
      while (res == CURLE_OK) {
#if (LIBSSH2_APINO >= 200706012030)
        ssize_t nread;

        while ((nread = libssh2_sftp_read(data->reqdata.proto.ssh->sftp_handle,
                                  buf, BUFSIZE-1)) == LIBSSH2_ERROR_EAGAIN);
#else /* !(LIBSSH2_APINO >= 200706012030) */
        size_t nread;
        /* NOTE: most *read() functions return ssize_t but this returns size_t
          which normally is unsigned! */
        nread = libssh2_sftp_read(data->reqdata.proto.ssh->sftp_handle,
                                  buf, BUFSIZE-1);
#endif /* !(LIBSSH2_APINO >= 200706012030) */

        if (nread > 0)
          buf[nread] = 0;

#if (LIBSSH2_APINO >= 200706012030)
        if (nread <= 0)
          break;
#else /* !(LIBSSH2_APINO >= 200706012030) */
        /* this check can be changed to a <= 0 when nread is changed to a
          signed variable type */
        if ((nread == 0) || (nread == (size_t)~0))
          break;
#endif /* !(LIBSSH2_APINO >= 200706012030) */

        bytecount += nread;

        res = Curl_client_write(conn, CLIENTWRITE_BODY, buf, nread);
        if(res)
          return res;

        Curl_pgrsSetDownloadCounter(data, bytecount);

        if(Curl_pgrsUpdate(conn))
          res = CURLE_ABORTED_BY_CALLBACK;
        else {
          struct timeval now = Curl_tvnow();
          res = Curl_speedcheck(data, now);
        }
      }
      if(Curl_pgrsUpdate(conn))
        res = CURLE_ABORTED_BY_CALLBACK;

      /* no (more) data to transfer */
      res = Curl_setup_transfer(conn, -1, -1, FALSE, NULL, -1, NULL);
    }
  }

  return res;
}

CURLcode Curl_sftp_done(struct connectdata *conn, CURLcode status,
                        bool premature)
{
  struct SSHPROTO *sftp = conn->data->reqdata.proto.ssh;
  CURLcode rc = CURLE_OK;
  int ret;
  (void)premature; /* not used */

  Curl_safefree(sftp->path);
  sftp->path = NULL;

  Curl_safefree(sftp->homedir);
  sftp->homedir = NULL;

  if (sftp->sftp_handle) {
#if (LIBSSH2_APINO >= 200706012030)
    while ((ret = libssh2_sftp_close(sftp->sftp_handle)) ==
           LIBSSH2_ERROR_EAGAIN);
    if (ret < 0) {
      infof(conn->data, "Failed to close libssh2 file\n");
    }
#else /* !(LIBSSH2_APINO >= 200706012030) */
    if (libssh2_sftp_close(sftp->sftp_handle) < 0) {
      infof(conn->data, "Failed to close libssh2 file\n");
    }
#endif /* !(LIBSSH2_APINO >= 200706012030) */
  }

  /* Before we shut down, see if there are any post-quote commands to send: */
  if(!status && !premature && conn->data->set.postquote) {
    infof(conn->data, "Sending postquote commands\n");
    rc = sftp_sendquote(conn, conn->data->set.postquote);
  }

  if (sftp->sftp_session) {
#if (LIBSSH2_APINO >= 200706012030)
    while ((ret = libssh2_sftp_shutdown(sftp->sftp_session)) ==
           LIBSSH2_ERROR_EAGAIN);
    if (ret < 0) {
      infof(conn->data, "Failed to stop libssh2 sftp subsystem\n");
    }
#else /* !(LIBSSH2_APINO >= 200706012030) */
    if (libssh2_sftp_shutdown(sftp->sftp_session) < 0) {
      infof(conn->data, "Failed to stop libssh2 sftp subsystem\n");
    }
#endif /* !(LIBSSH2_APINO >= 200706012030) */
  }

  if (sftp->ssh_channel) {
#if (LIBSSH2_APINO >= 200706012030)
    while ((ret = libssh2_channel_close(sftp->ssh_channel)) ==
           LIBSSH2_ERROR_EAGAIN);
    if (ret < 0) {
      infof(conn->data, "Failed to stop libssh2 channel subsystem\n");
    }
#else /* !(LIBSSH2_APINO >= 200706012030) */
    if (libssh2_channel_close(sftp->ssh_channel) < 0) {
      infof(conn->data, "Failed to stop libssh2 channel subsystem\n");
    }
#endif /* !(LIBSSH2_APINO >= 200706012030) */
  }

  if (sftp->ssh_session) {
#if (LIBSSH2_APINO >= 200706012030)
    while (libssh2_session_disconnect(sftp->ssh_session, "Shutdown") ==
           LIBSSH2_ERROR_EAGAIN);
#else /* !(LIBSSH2_APINO >= 200706012030) */
    libssh2_session_disconnect(sftp->ssh_session, "Shutdown");
#endif /* !(LIBSSH2_APINO >= 200706012030) */
    libssh2_session_free(sftp->ssh_session);
    sftp->ssh_session = NULL;
  }

  free(conn->data->reqdata.proto.ssh);
  conn->data->reqdata.proto.ssh = NULL;
  Curl_pgrsDone(conn);

  (void)status; /* unused */
  (void)ret;    /* possibly unused */

  return rc;
}

/* return number of received (decrypted) bytes */
ssize_t Curl_sftp_send(struct connectdata *conn, int sockindex,
                       void *mem, size_t len)
{
  ssize_t nwrite;   /* libssh2_sftp_write() used to return size_t in 0.14
                       but is changed to ssize_t in 0.15! */

#if defined(LIBSSH2SFTP_EAGAIN) && (LIBSSH2_APINO < 200706012030)
  /* we prefer the non-blocking API but that didn't exist previously */
  nwrite = (ssize_t)
    libssh2_sftp_writenb(conn->data->reqdata.proto.ssh->sftp_handle, mem, len);
#else
  nwrite = (ssize_t)
    libssh2_sftp_write(conn->data->reqdata.proto.ssh->sftp_handle, mem, len);
#if (LIBSSH2_APINO >= 200706012030)
  if (nwrite == LIBSSH2_ERROR_EAGAIN) {
    return 0;
  }
#endif
#endif
  (void)sockindex;
  return nwrite;
}

/*
 * If the read would block (EWOULDBLOCK) we return -1. Otherwise we return
 * a regular CURLcode value.
 */
ssize_t Curl_sftp_recv(struct connectdata *conn, int sockindex,
                       char *mem, size_t len)
{
  ssize_t nread;
  (void)sockindex;

  /* libssh2_sftp_read() returns size_t !*/

#if defined(LIBSSH2SFTP_EAGAIN) && (LIBSSH2_APINO < 200706012030)
  /* we prefer the non-blocking API but that didn't exist previously */
  nread = (ssize_t)
    libssh2_sftp_readnb(conn->data->reqdata.proto.ssh->sftp_handle, mem, len);
#else
  nread = (ssize_t)
    libssh2_sftp_read(conn->data->reqdata.proto.ssh->sftp_handle, mem, len);
#endif
  return nread;
}

/* The get_pathname() function is being borrowed from OpenSSH sftp.c
   version 4.6p1. */
/*
 * Copyright (c) 2001-2004 Damien Miller <djm@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */
static int
get_pathname(const char **cpp, char **path)
{
  const char *cp = *cpp, *end;
  char quot;
  u_int i, j;
  static const char * const WHITESPACE = " \t\r\n";

  cp += strspn(cp, WHITESPACE);
  if (!*cp) {
    *cpp = cp;
    *path = NULL;
    return CURLE_FTP_QUOTE_ERROR;
  }

  *path = malloc(strlen(cp) + 1);
  if (*path == NULL)
    return CURLE_OUT_OF_MEMORY;

  /* Check for quoted filenames */
  if (*cp == '\"' || *cp == '\'') {
    quot = *cp++;

    /* Search for terminating quote, unescape some chars */
    for (i = j = 0; i <= strlen(cp); i++) {
      if (cp[i] == quot) {  /* Found quote */
        i++;
        (*path)[j] = '\0';
        break;
      }
      if (cp[i] == '\0') {  /* End of string */
        /*error("Unterminated quote");*/
        goto fail;
      }
      if (cp[i] == '\\') {  /* Escaped characters */
        i++;
        if (cp[i] != '\'' && cp[i] != '\"' &&
            cp[i] != '\\') {
          /*error("Bad escaped character '\\%c'",
              cp[i]);*/
          goto fail;
        }
      }
      (*path)[j++] = cp[i];
    }

    if (j == 0) {
      /*error("Empty quotes");*/
      goto fail;
    }
    *cpp = cp + i + strspn(cp + i, WHITESPACE);
  }
  else {
    /* Read to end of filename */
    end = strpbrk(cp, WHITESPACE);
    if (end == NULL)
      end = strchr(cp, '\0');
    *cpp = end + strspn(end, WHITESPACE);

    memcpy(*path, cp, end - cp);
    (*path)[end - cp] = '\0';
  }
  return (0);

  fail:
    free(*path);
    *path = NULL;
    return CURLE_FTP_QUOTE_ERROR;
}


static const char *sftp_libssh2_strerror(unsigned long err)
{
  switch (err) {
  case LIBSSH2_FX_NO_SUCH_FILE:
    return "No such file or directory";
  case LIBSSH2_FX_PERMISSION_DENIED:
    return "Permission denied";
  case LIBSSH2_FX_FAILURE:
    return "Operation failed";
  case LIBSSH2_FX_BAD_MESSAGE:
    return "Bad message from SFTP server";
  case LIBSSH2_FX_NO_CONNECTION:
    return "Not connected to SFTP server";
  case LIBSSH2_FX_CONNECTION_LOST:
    return "Connection to SFTP server lost";
  case LIBSSH2_FX_OP_UNSUPPORTED:
    return "Operation not supported by SFTP server";
  case LIBSSH2_FX_INVALID_HANDLE:
    return "Invalid handle";
  case LIBSSH2_FX_NO_SUCH_PATH:
    return "No such file or directory";
  case LIBSSH2_FX_FILE_ALREADY_EXISTS:
    return "File already exists";
  case LIBSSH2_FX_WRITE_PROTECT:
    return "File is write protected";
  case LIBSSH2_FX_NO_MEDIA:
    return "No media";
  case LIBSSH2_FX_NO_SPACE_ON_FILESYSTEM:
    return "Disk full";
  case LIBSSH2_FX_QUOTA_EXCEEDED:
    return "User quota exceeded";
  case LIBSSH2_FX_UNKNOWN_PRINCIPLE:
    return "Unknown principle";
  case LIBSSH2_FX_LOCK_CONFlICT:
    return "File lock conflict";
  case LIBSSH2_FX_DIR_NOT_EMPTY:
    return "Directory not empty";
  case LIBSSH2_FX_NOT_A_DIRECTORY:
    return "Not a directory";
  case LIBSSH2_FX_INVALID_FILENAME:
    return "Invalid filename";
  case LIBSSH2_FX_LINK_LOOP: