xref: /linux/certs/check-blacklist-hashes.awk (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1#!/usr/bin/awk -f
2# SPDX-License-Identifier: GPL-2.0
3#
4# Copyright © 2020, Microsoft Corporation. All rights reserved.
5#
6# Author: Mickaël Salaün <mic@linux.microsoft.com>
7#
8# Check that a CONFIG_SYSTEM_BLACKLIST_HASH_LIST file contains a valid array of
9# hash strings.  Such string must start with a prefix ("tbs" or "bin"), then a
10# colon (":"), and finally an even number of hexadecimal lowercase characters
11# (up to 128).
12
13BEGIN {
14	RS = ","
15}
16{
17	if (!match($0, "^[ \t\n\r]*\"([^\"]*)\"[ \t\n\r]*$", part1)) {
18		print "Not a string (item " NR "):", $0;
19		exit 1;
20	}
21	if (!match(part1[1], "^(tbs|bin):(.*)$", part2)) {
22		print "Unknown prefix (item " NR "):", part1[1];
23		exit 1;
24	}
25	if (!match(part2[2], "^([0-9a-f]+)$", part3)) {
26		print "Not a lowercase hexadecimal string (item " NR "):", part2[2];
27		exit 1;
28	}
29	if (length(part3[1]) > 128) {
30		print "Hash string too long (item " NR "):", part3[1];
31		exit 1;
32	}
33	if (length(part3[1]) % 2 == 1) {
34		print "Not an even number of hexadecimal characters (item " NR "):", part3[1];
35		exit 1;
36	}
37}
38