Fetch Softworks

Fetch 5.3, transparent proxy, pasv command (5 posts)

• Started 15 years ago by guybrush
• Latest reply 15 years ago from guybrush

• guybrush Member

  Hi

  I try to get my transparent ftp-proxy setup up and running. And I am stumbling a bit.

  It seems to me, that Fetch *always* tries to open its data connection to the IP-address it originally wanted to connect to.

  This means, if the proxy sends its IP with the "Entering Passive Mode" message, Fetch won't connect to the proxy, but tries to connect to the original server (which is not reachable because of the firewall, hence the proxy...).

  Is this "by design"? Or is this "a bug"? Or am I getting something conceptually wrong here?

  Kind regards
  guybrush

  Posted 15 years ago #

• guybrush Member

  Hi

  Here is some more information.

  From the Fetch Transcript:

  227 Entering Passive Mode (192,168,1,1,105,72)
  Making data connection to 130.59.10.36 port 26952
  ABOR
  500 Unknown command.
  PORT 192,168,1,10,192,21
  200 PORT command successful.
  LIST -al
  150 Here comes the directory listing.
  Active mode connection blocked by Mac OS X firewall, port 49173
  ABOR

  So it seems to me that fetch tries to connect to the (wrong) IP (not the proxy but the original server) and eventually times out. It then tries active FTP which does not work either because of the firewall.

  I found that if I use curl on the commandline, it works, unless I use --ftp-skip-pasv-ip (which makes sense). So it seems to me curl's --ftp-skip-pasv-ip is Fetch's default behaviour (maybe for security reasons?).

  For the curl man page, see http://developer.apple.com/documentation/Darwin/Reference/ManPages/man1/curl.1.html

  Can anyone make sense of this?

  Kind regards
  guybrush

  Posted 15 years ago #

• Jim Matthews Administrator

  Hi,

  That's correct, as of Fetch 5.2 we have the same behavior as curl's --ftp-skil-pasv-ip option. We made the change to make Fetch compatible with servers behind port-mapping Network Address Translation (NAT) devices. But this behavior seems like a bug in your situation.

  Could you post (or email to bugs at fetchsoftworks dot com) a complete transcript of a connection attempt? It would also be helpful to know the name of the transparent ftp proxy server software you are using.

  Thanks,

  Posted 15 years ago #

• guybrush Member

  Hi JimMatthews

  Thank you for coming back to me.

  I sent you a complete transcript by mail to the address you indicated. And I am posting the same transcript here for reference.

  Fetch 5.3 (5D161) PowerPC running on Mac OS X 10.4.11 (8S165) PowerPC English
  StuffIt Engine 0x820, StuffIt SDK Version 10.1.1b1
  Partial serial FETCHED001-M445-3MTR T
  Connecting to mirror.switch.ch port 21 (Mac OS X firewall is on) (1/7/09 9:59:28 PM)
  Connected to 130.59.10.36 port 21 (1/7/09 9:59:28 PM)
  220 FTP proxy (v0.13.5) ready
  ADAT
  530 Login incorrect. Expected USER command
  AUTH This command is checking whether this server supports Kerberos or GSS security, see RFC 2228
  530 Login incorrect. Expected USER command
  USER anonymous
  331-SWITCHmirror (formerly known as Swiss SunSITE) welcomes you!
  331-
  331 Please specify the password.
  PASS
  230- Welcome to SWITCHmirror ftp://mirror.switch.ch/
  230- ----------------------- http://mirror.switch.ch/
  230-
  230- SWITCHmirror is located in Zurich, Switzerland and
  230- operated by SWITCH: http://www.switch.ch/
  230-
  230- If you have problems downloading and are seeing "Access denied"
  230- or "Permission denied", please make sure that you started your
  230- FTP client in a directory to which you have write permission.
  230-
  230- Contact address: switchmirror@switch.ch
  230-
  230- NOTE: ALL transfers are logged and any misuse will be acted upon.
  230-
  230 Login successful.
  SYST
  215 UNIX Type: L8
  PWD
  257 "/"
  MACB ENABLE
  500 Unknown command.
  PWD
  257 "/"
  TYPE A
  200 Type set to A
  PASV
  227 Entering Passive Mode (192,168,1,1,105,88)
  Making data connection to 130.59.10.36 port 26968
  ABOR
  500 Unknown command.
  PORT 192,168,1,10,192,19
  200 PORT command successful.
  LIST -al
  150 Here comes the directory listing.
  Active mode connection blocked by Mac OS X firewall, port 49171
  ABOR
  ftp_list: 2,-30031 (state == GETTING_LIST)
  QUIT
  send_cmd():con_conn->Putline() returns 2,32767
  Update check skipped at 01/07/2009 10:01 PM (next check after 01/12/2009 01:15 PM)

  The proxy-software I am using is jftpgw v0.13.5 ( http://www.mcknight.de/jftpgw/ ).

  Any help is greatly appreciated. If you (or anyone) needs more information, I will be happy to provide it.

  Kind regards
  guybrush

  Posted 15 years ago #

• guybrush Member

  Hi Everyone

  Jim Matthews provided me with a experimental version of Fetch that can do what curl can do with the (not) --ftp-skip-pasv-ip option. This works like a charm.

  The (configurable) option will be part of a future version of Fetch. Thank you very much! This was the most exceptional support I ever encountered (can you say so? I am not a native english speaker...).

  Kind regards
  guybrush

  Posted 15 years ago #