https://bugs.gentoo.org/560418 fix from upstream From 075d7556964f5a871a73c22ac4b69f5361295099 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Tim=20R=C3=BChsen?= Date: Tue, 11 Aug 2015 16:48:08 +0200 Subject: [PATCH] Fix IP address exposure in FTP code * src/ftp.c (getftp): Do not use PORT when PASV fails. * tests/FTPServer.px: Add pasv_not_supported server flag. * tests/Makefile.am: Add Test-ftp-pasv-not-supported.px * tests/Test-ftp-pasv-not-supported.px: New test Fix IP address exposure when automatically falling back from passive mode to active mode (using the PORT command). A behavior that may be used to expose a client's privacy even when using a proxy. --- NEWS | 2 ++ src/ftp.c | 19 +++++++----- tests/FTPServer.pm | 8 +++++ tests/Makefile.am | 3 +- tests/Test-ftp-pasv-not-supported.px | 60 ++++++++++++++++++++++++++++++++++++ 5 files changed, 84 insertions(+), 8 deletions(-) create mode 100755 tests/Test-ftp-pasv-not-supported.px diff --git a/src/ftp.c b/src/ftp.c index 68f1a33..9dab99c 100644 --- a/src/ftp.c +++ b/src/ftp.c @@ -252,7 +252,6 @@ getftp (struct url *u, wgint passed_expected_bytes, wgint *qtyread, char *respline, *tms; const char *user, *passwd, *tmrate; int cmd = con->cmd; - bool pasv_mode_open = false; wgint expected_bytes = 0; bool got_expected_bytes = false; bool rest_failed = false; @@ -883,13 +882,19 @@ Error in server response, closing control connection.\n")); ? CONERROR : CONIMPOSSIBLE); } - pasv_mode_open = true; /* Flag to avoid accept port */ if (!opt.server_response) logputs (LOG_VERBOSE, _("done. ")); - } /* err==FTP_OK */ - } + } + else + return err; - if (!pasv_mode_open) /* Try to use a port command if PASV failed */ + /* + * We do not want to fall back from PASSIVE mode to ACTIVE mode ! + * The reason is the PORT command exposes the client's real IP address + * to the server. Bad for someone who relies on privacy via a ftp proxy. + */ + } + else { err = ftp_do_port (csock, &local_sock); /* FTPRERR, WRITEFAILED, bindport (FTPSYSERR), HOSTERR, @@ -1148,8 +1153,8 @@ Error in server response, closing control connection.\n")); } /* If no transmission was required, then everything is OK. */ - if (!pasv_mode_open) /* we are not using pasive mode so we need - to accept */ + if (!opt.ftp_pasv) /* we are not using passive mode so we need + to accept */ { /* Wait for the server to connect to the address we're waiting at. */ -- 2.5.1