download: fix file:// BR2_PRIMARY_SITE (download cache)
authorHollis Blanchard <hollis_blanchard@mentor.com>
Wed, 15 Aug 2018 23:44:34 +0000 (16:44 -0700)
committerThomas Petazzoni <thomas.petazzoni@bootlin.com>
Mon, 20 Aug 2018 22:24:29 +0000 (00:24 +0200)
commit38de43412327b68de1943ead3fea512ec42be625
tree531eb5864ede543ae2143dac19ec0e2189a92d81
parentac26da5275af39e723547e0945de03752051e1ae
download: fix file:// BR2_PRIMARY_SITE (download cache)

wget is the only downloader currently usable with BR2_PRIMARY_SITE, and that
doesn't work at all for file:// URLs. The symptoms are these:

support/download/dl-wrapper -c '2.4.47' -d '/PATH/build/sw/source/attr' -D '/PATH/build/sw/source' -f 'attr-2.4.47.src.tar.gz' -H 'package/attr//attr.hash' -n 'attr-2.4.47' -N 'attr' -o '/PATH/build/sw/source/attr/attr-2.4.47.src.tar.gz'  -u file\|urlencode+file:///NFS/buildroot_dl_cache/attr -u file\|urlencode+file:///NFS/buildroot_dl_cache -u http+http://download.savannah.gnu.org/releases/attr -u http\|urlencode+http://sources.buildroot.net/attr -u http\|urlencode+http://sources.buildroot.net  --
file:///NFS/buildroot_dl_cache/attr/attr-2.4.47.src.tar.gz: Unsupported scheme `file'.
ERROR: attr-2.4.47.src.tar.gz has wrong sha256 hash:
ERROR: expected: 25772f653ac5b2e3ceeb89df50e4688891e21f723c460636548971652af0a859
ERROR: got     : e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855
ERROR: Incomplete download, or man-in-the-middle (MITM) attack

In the case of custom Linux kernel versions, this is fatal, because there isn't
necessarily a hash file to indicate that wget's empty tarball is wrong.

This seems to have been broken by commit c8ef0c03b0b, because:
1. BR2_PRIMARY_SITE always appends "urlencode" (package/pkg-download.mk)
2. Anything with the "|urlencode" suffix in $uri will end up using wget due to
   the backend case wildcarding.
3. The wget backend rejects file:/// URLs ("unsupported scheme"), and we end up
   with an empty .tar.gz file in the downloads directory.

Fix that by shell-extracting the backend name from the left of "|". I'm not
positive if all URLs will have a "|", so this code only looks for a "|" left of
the "+".

Signed-off-by: Hollis Blanchard <hollis_blanchard@mentor.com>
Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Tested-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
support/download/dl-wrapper