promote filesize to a hashstring

It is a very simple hashstring, which is why it isn't contributing to
the usability of a list of them, but it is also trivial to check and
calculate, so it doesn't hurt checking it either as it can combined even
with the simplest other hashes greatly complicate attacks on them as you
suddenly need a same-size hash collision, which is usually a lot harder
to achieve.

1 files changed, 55 insertions, 0 deletions

diff --git a/test/integration/test-apt-update-filesize-mismatch b/test/integration/test-apt-update-filesize-mismatch
new file mode 100755
index 000000000..8c73c059e
--- /dev/null
+++ b/test/integration/test-apt-update-filesize-mismatch
@@ -0,0 +1,55 @@
+#!/bin/sh
+set -e
+
+TESTDIR=$(readlink -f $(dirname $0))
+. $TESTDIR/framework
+setupenvironment
+configarchitecture 'i386'
+configcompression 'gz'
+
+insertpackage 'testing' 'foo' 'all' '1'
+insertpackage 'testing' 'foo2' 'all' '1'
+insertsource 'testing' 'foo' 'all' '1'
+insertsource 'testing' 'foo2' 'all' '1'
+
+setupaptarchive --no-update
+changetowebserver
+
+find aptarchive \( -name 'Packages' -o -name 'Sources' -o -name 'Translation-en' \) -delete
+for release in $(find aptarchive -name 'Release'); do
+	cp "$release" "${release}.backup"
+done
+
+testsuccess aptget update
+testsuccess aptcache show foo
+testsuccess aptget install foo -s
+
+for get in $(sed -n 's#^GET /\([^ ]\+\.gz\) HTTP.\+$#\1#p' aptarchive/webserver.log); do
+	for ext in '' '.gz'; do
+		COMPRESSFILE="$get"
+		get="${get}${ext}"
+		FILE="$(basename -s '.gz' "$get")"
+		msgmsg 'Test filesize mismatch with file' "$FILE"
+		rm -rf rootdir/var/lib/apt/lists
+
+		for release in $(find aptarchive -name 'Release'); do
+			SIZE="$(awk "/$FILE\$/ { print \$2; exit }" "${release}.backup")"
+			sed "s# $SIZE # $(($SIZE + 111)) #" "${release}.backup" > "$release"
+		done
+		signreleasefiles
+
+		TEST='testfailure'
+		if expr match "$COMPRESSFILE" '^.*Translation-.*$' >/dev/null; then
+			TEST='testsuccess'
+			unset COMPRESSFILE
+		fi
+		$TEST aptget update -o Debug::pkgAcquire::Worker=1
+		cp rootdir/tmp/${TEST}.output rootdir/tmp/update.output
+		testsuccess grep -E "$(basename -s '.gz' "$COMPRESSFILE").*Hash Sum mismatch" rootdir/tmp/update.output
+		$TEST aptcache show foo
+		$TEST aptget install foo -s
+
+		testfailure aptcache show bar
+		testfailure aptget install bar -s
+	done
+done