see http://lists.nongnu.org/archive/html/mingw-cross-env-list/2014-07/msg00002.html
Many FTP servers block connections from Tor and some
VPN servers. HTTP servers don't do this normally.
Example of failed FTP download attempt of binutils-2.24.tar.bz:
$ torsocks wget ftp://ftp.gnu.org/pub/gnu/binutils/binutils-2.24.tar.bz2
--2014-07-20 13:26:48-- ftp://ftp.gnu.org/pub/gnu/binutils/binutils-2.24.tar.bz2
=> `binutils-2.24.tar.bz2'
Resolving ftp.gnu.org (ftp.gnu.org)... 208.118.235.20
Connecting to ftp.gnu.org (ftp.gnu.org)|208.118.235.20|:21... connected.
Logging in as anonymous ... Logged in!
==> SYST ... done. ==> PWD ... done.
==> TYPE I ... done. ==> CWD (1) /pub/gnu/binutils ... done.
==> SIZE binutils-2.24.tar.bz2 ... 22716802
==> PASV ... done. ==> RETR binutils-2.24.tar.bz2 ...
Error in server response, closing control connection.
Retrying.
Same package was downloaded via HTTP successfully:
$ torsocks wget http://ftp.gnu.org/pub/gnu/binutils/binutils-2.24.tar.bz2
--2014-07-20 13:32:37-- http://ftp.gnu.org/pub/gnu/binutils/binutils-2.24.tar.bz2
Resolving ftp.gnu.org (ftp.gnu.org)... 208.118.235.20
Connecting to ftp.gnu.org (ftp.gnu.org)|208.118.235.20|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 22716802 (22M) [application/x-bzip2]
Saving to: `binutils-2.24.tar.bz2'
100%[=================>] 22,716,802 721K/s in 24s
2014-07-20 13:33:03 (915 KB/s) - `binutils-2.24.tar.bz2' saved [22716802/22716802]
Trying download from Tor Browser, I get error message:
425 Security: Bad IP connecting.
HTTP URLs were added to FTP URLs-only packages.
In many cases, ftp://ftp.gnu.org can be accessed
from http://ftp.gnu.org
If both URLs of a package are FTP, then one of them
was replaced with HTTP.
Command to check that those packages can be build successfully
if behind Tor:
$ torsocks make autoconf automake binutils bison cloog coreutils file freetds gcc gdb gettext gmp gnutls gperf isl libbluray libffi libgcrypt libgpg_error libidn libmicrohttpd libpng libxml2 libxslt m4 pthreads-w32 sed dcmtk mpfr
I've run the test above successfully.
Boris Nagaev
Tony Theodore
Mark Brand