As discussed in #10749, I suggested that we remove FTP support to reduce possible attack surface
as there are no Alpine mirrors which use FTP.

There are also no known mirrors of any other apk-using distribution which use FTP, so I believe
we are safe to remove support for FTP-based mirrors in apk-tools 3.

Signed-off-by: Ariadne Conill <ariadne@dereferenced.org>

fixes #10776

fixes #10650

Mike Detwiler authored 4 years ago and Timo Teräs committed 4 years ago

Signed-off-by: Mike Detwiler <det@shift5.io>

ftp://ftp.fu-berlin.de/unix/NetBSD/packages/current-src/pkgsrc/net/libfetch/files

libfetch comes (at least) in netbsd and freebsd flavors which
differing functionality. Alpine and Arch package netbsd one,
but it's not widely packaged across other distributions.

We need NetBSD version as it does not use funopen(3) which is not
supported in musl, and supports connection pooling.

FreeBSD seems to be the orignal and better maintained version
with support for SSL CAs, client certificate authentication,
proxy authentication, and improved http redirect handling.

So this imports NetBSD version, and future commits will pick up
the needed improvements from FreeBSD tree.

Incidentally, this also fixes #7857 and likes for good.