xref: /linux/tools/testing/selftests/bpf/verify_sig_setup.sh (revision 4b660dbd9ee2059850fd30e0df420ca7a38a1856) 
1#!/bin/bash
2# SPDX-License-Identifier: GPL-2.0
3
4set -e
5set -u
6set -o pipefail
7
8VERBOSE="${SELFTESTS_VERBOSE:=0}"
9LOG_FILE="$(mktemp /tmp/verify_sig_setup.log.XXXXXX)"
10
11x509_genkey_content="\
12[ req ]
13default_bits = 2048
14distinguished_name = req_distinguished_name
15prompt = no
16string_mask = utf8only
17x509_extensions = myexts
18
19[ req_distinguished_name ]
20CN = eBPF Signature Verification Testing Key
21
22[ myexts ]
23basicConstraints=critical,CA:FALSE
24keyUsage=digitalSignature
25subjectKeyIdentifier=hash
26authorityKeyIdentifier=keyid
27"
28
29usage()
30{
31	echo "Usage: $0 <setup|cleanup <existing_tmp_dir>"
32	exit 1
33}
34
35setup()
36{
37	local tmp_dir="$1"
38
39	echo "${x509_genkey_content}" > ${tmp_dir}/x509.genkey
40
41	openssl req -new -nodes -utf8 -sha256 -days 36500 \
42			-batch -x509 -config ${tmp_dir}/x509.genkey \
43			-outform PEM -out ${tmp_dir}/signing_key.pem \
44			-keyout ${tmp_dir}/signing_key.pem 2>&1
45
46	openssl x509 -in ${tmp_dir}/signing_key.pem -out \
47		${tmp_dir}/signing_key.der -outform der
48
49	key_id=$(cat ${tmp_dir}/signing_key.der | keyctl padd asymmetric ebpf_testing_key @s)
50
51	keyring_id=$(keyctl newring ebpf_testing_keyring @s)
52	keyctl link $key_id $keyring_id
53}
54
55cleanup() {
56	local tmp_dir="$1"
57
58	keyctl unlink $(keyctl search @s asymmetric ebpf_testing_key) @s
59	keyctl unlink $(keyctl search @s keyring ebpf_testing_keyring) @s
60	rm -rf ${tmp_dir}
61}
62
63fsverity_create_sign_file() {
64	local tmp_dir="$1"
65
66	data_file=${tmp_dir}/data-file
67	sig_file=${tmp_dir}/sig-file
68	dd if=/dev/urandom of=$data_file bs=1 count=12345 2> /dev/null
69	fsverity sign --key ${tmp_dir}/signing_key.pem $data_file $sig_file
70
71	# We do not want to enable fsverity on $data_file yet. Try whether
72	# the file system support fsverity on a different file.
73	touch ${tmp_dir}/tmp-file
74	fsverity enable ${tmp_dir}/tmp-file
75}
76
77fsverity_enable_file() {
78	local tmp_dir="$1"
79
80	data_file=${tmp_dir}/data-file
81	fsverity enable $data_file
82}
83
84catch()
85{
86	local exit_code="$1"
87	local log_file="$2"
88
89	if [[ "${exit_code}" -ne 0 ]]; then
90		cat "${log_file}" >&3
91	fi
92
93	rm -f "${log_file}"
94	exit ${exit_code}
95}
96
97main()
98{
99	[[ $# -ne 2 ]] && usage
100
101	local action="$1"
102	local tmp_dir="$2"
103
104	[[ ! -d "${tmp_dir}" ]] && echo "Directory ${tmp_dir} doesn't exist" && exit 1
105
106	if [[ "${action}" == "setup" ]]; then
107		setup "${tmp_dir}"
108	elif [[ "${action}" == "cleanup" ]]; then
109		cleanup "${tmp_dir}"
110	elif [[ "${action}" == "fsverity-create-sign" ]]; then
111		fsverity_create_sign_file "${tmp_dir}"
112	elif [[ "${action}" == "fsverity-enable" ]]; then
113		fsverity_enable_file "${tmp_dir}"
114	else
115		echo "Unknown action: ${action}"
116		exit 1
117	fi
118}
119
120trap 'catch "$?" "${LOG_FILE}"' EXIT
121
122if [[ "${VERBOSE}" -eq 0 ]]; then
123	# Save the stderr to 3 so that we can output back to
124	# it incase of an error.
125	exec 3>&2 1>"${LOG_FILE}" 2>&1
126fi
127
128main "$@"
129rm -f "${LOG_FILE}"
130