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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?= <tim.ruehsen@gmx.de>
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. */
diff --git a/tests/FTPServer.pm b/tests/FTPServer.pm
index c0a6e47..a5185d6 100644
--- a/tests/FTPServer.pm
+++ b/tests/FTPServer.pm
@@ -740,6 +740,14 @@ sub run
last;
}
+ if (defined($self->{_server_behavior}{pasv_not_supported})
+ && $cmd eq 'PASV')
+ {
+ print {$conn->{socket}}
+ "500 PASV not supported.\r\n";
+ next;
+ }
+
# Run the command.
&{$command_table->{$cmd}}($conn, $cmd, $rest);
}
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 5d387aa..daf162f 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -127,7 +127,8 @@ PX_TESTS = \
Test--start-pos.px \
Test--start-pos--continue.px \
Test--httpsonly-r.px \
- Test-204.px
+ Test-204.px \
+ Test-ftp-pasv-not-supported.px
EXTRA_DIST = FTPServer.pm FTPTest.pm HTTPServer.pm HTTPTest.pm \
WgetTests.pm WgetFeature.pm WgetFeature.cfg $(PX_TESTS) \
diff --git a/tests/Test-ftp-pasv-not-supported.px b/tests/Test-ftp-pasv-not-supported.px
new file mode 100755
index 0000000..97d0610
--- /dev/null
+++ b/tests/Test-ftp-pasv-not-supported.px
@@ -0,0 +1,60 @@
+#!/usr/bin/env perl
+
+use strict;
+use warnings;
+
+use FTPTest;
+
+# This test checks whether Wget *does not* fall back from passive mode to
+# active mode using a PORT command. Wget <= 1.16.3 made a fallback exposing
+# the client's real IP address to the remote FTP server.
+#
+# This behavior circumvents expected privacy when using a proxy / proxy network (e.g. Tor).
+#
+# Wget >= 1.16.4 does it right. This test checks it.
+
+###############################################################################
+
+# From bug report 10.08.2015 from tomtidaly@sigaint.org
+my $afile = <<EOF;
+FTP PORT command code in v1.16.3?
+
+In the past it could be possible for a site over http connection to
+redirect wget to FPT using FTP PORT command so the site gets the real IP
+of the computer even when wget proxy command is in use I believe:
+https://lists.torproject.org/pipermail/tor-talk/2012-April/024040.html
+
+Is that code still present in wget v1.16.3? It was present in v1.13.4.
+EOF
+
+$afile =~ s/\n/\r\n/g;
+
+
+# code, msg, headers, content
+my %urls = (
+ '/afile.txt' => {
+ content => $afile,
+ },
+);
+
+my $cmdline = $WgetTest::WGETPATH . " -S ftp://localhost:{{port}}/afile.txt";
+
+my $expected_error_code = 8;
+
+my %expected_downloaded_files = (
+ 'afile.txt' => {
+ content => $afile,
+ },
+);
+
+###############################################################################
+
+my $the_test = FTPTest->new (
+ server_behavior => {pasv_not_supported => 1},
+ input => \%urls,
+ cmdline => $cmdline,
+ errcode => $expected_error_code,
+ output => \%expected_downloaded_files);
+exit !$the_test->run();
+
+# vim: et ts=4 sw=4
--
2.5.1
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