[yocto] [meta-security 2/3] kernel-modsign.bbclass: add support for kernel modules signing

[Dmitry Eremin-Solenikov]

From: Dmitry Eremin-Solenikov <dmitry_eremin-solenikov at mentor.com>

Add bbclass responsible for handling signing of kernel modules.

Signed-off-by: Dmitry Eremin-Solenikov <dmitry_eremin-solenikov at mentor.com>
---
 meta-integrity/classes/kernel-modsign.bbclass | 29 +++++++++++++++++++
 .../data/debug-keys/privkey_modsign.pem       | 28 ++++++++++++++++++
 .../data/debug-keys/x509_modsign.crt          | 22 ++++++++++++++
 3 files changed, 79 insertions(+)
 create mode 100644 meta-integrity/classes/kernel-modsign.bbclass
 create mode 100644 meta-integrity/data/debug-keys/privkey_modsign.pem
 create mode 100644 meta-integrity/data/debug-keys/x509_modsign.crt

diff --git a/meta-integrity/classes/kernel-modsign.bbclass b/meta-integrity/classes/kernel-modsign.bbclass
new file mode 100644
index 000000000000..1e4d94b79091
--- /dev/null
+++ b/meta-integrity/classes/kernel-modsign.bbclass
@@ -0,0 +1,29 @@
+# No default! Either this or MODSIGN_PRIVKEY/MODSIGN_X509 have to be
+# set explicitly in a local.conf before activating kernel-modsign.
+# To use the insecure (because public) example keys, use
+# MODSIGN_KEY_DIR = "${INTEGRITY_BASE}/data/debug-keys"
+MODSIGN_KEY_DIR ?= "MODSIGN_KEY_DIR_NOT_SET"
+
+# Private key for modules signing. The default is okay when
+# using the example key directory.
+MODSIGN_PRIVKEY ?= "${MODSIGN_KEY_DIR}/privkey_modsign.pem"
+
+# Public part of certificates used for modules signing.
+# The default is okay when using the example key directory.
+MODSIGN_X509 ?= "${MODSIGN_KEY_DIR}/x509_modsign.crt"
+
+# If this class is enabled, disable stripping signatures from modules
+INHIBIT_PACKAGE_STRIP = "1"
+
+do_configure_prepend() {
+    if [ -f "${MODSIGN_PRIVKEY}" -a -f "${MODSIGN_X509}" ]; then
+        cat "${MODSIGN_PRIVKEY}" "${MODSIGN_X509}" \
+            > "${B}/modsign_key.pem"
+    else
+        bberror "Either modsign key or certificate are invalid"
+    fi
+}
+
+do_shared_workdir_append() {
+    cp modsign_key.pem $kerneldir/
+}
diff --git a/meta-integrity/data/debug-keys/privkey_modsign.pem b/meta-integrity/data/debug-keys/privkey_modsign.pem
new file mode 100644
index 000000000000..4cac00ae303a
--- /dev/null
+++ b/meta-integrity/data/debug-keys/privkey_modsign.pem
@@ -0,0 +1,28 @@
+-----BEGIN PRIVATE KEY-----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+-----END PRIVATE KEY-----
diff --git a/meta-integrity/data/debug-keys/x509_modsign.crt b/meta-integrity/data/debug-keys/x509_modsign.crt
new file mode 100644
index 000000000000..5fa2a9062a89
--- /dev/null
+++ b/meta-integrity/data/debug-keys/x509_modsign.crt
@@ -0,0 +1,22 @@
+-----BEGIN CERTIFICATE-----
+MIIDnjCCAoagAwIBAgIUUqmBj5Q8edHMMTXsoGVGEEKdwV4wDQYJKoZIhvcNAQEL
+BQAwZzEqMCgGA1UEAxMhbWV0YS1zZWN1cml0eSBtb2R1bGVzIHNpZ25pbmcga2V5
+MRQwEgYDVQQKEwtleGFtcGxlLmNvbTEjMCEGCSqGSIb3DQEJARYUam9obi5kb2VA
+ZXhhbXBsZS5jb20wIBcNMTkwNzI3MjIzOTA3WhgPMjExOTA3MjcyMjM5MTVaMGcx
+KjAoBgNVBAMTIW1ldGEtc2VjdXJpdHkgbW9kdWxlcyBzaWduaW5nIGtleTEUMBIG
+A1UEChMLZXhhbXBsZS5jb20xIzAhBgkqhkiG9w0BCQEWFGpvaG4uZG9lQGV4YW1w
+bGUuY29tMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAxFrCYwdqQOSI
+ehHpV71Y8FmNYsdWszHIjUTTz0DdQDFxdCv1VJHzmG2j2o4NXEGBH/YJN6uzmeQM
+ZFGP3uaYmTkWj3LJo9JVdC/jUpUWMnUeTP0MbRM9uufORYKkRnQHurpkrT5lSnam
+tnevDuD4EICSbVbs+p3ZvtLjRFAwlS8IZBkEsDQd6gW2QFF/XrHGf2vHlIgXzGCm
+jpPCUcjPtm6/XYKUxYOFHwWHsYDUkKPIOUyARnPCoEIigrhY9X0BIVec+EbrB7YY
+3DWF2t0R5nXJccqxnmK+WUXOOx6hNYHeTQ0dFnh5+AuGCnHyta2Wc/9vuoX7CEXx
+senECpNt4QIDAQABo0AwPjAMBgNVHRMBAf8EAjAAMA8GA1UdDwEB/wQFAwMHgAAw
+HQYDVR0OBBYEFDa35X9LnPlrd76inh/cYgeXh6X4MA0GCSqGSIb3DQEBCwUAA4IB
+AQBTPTh7zY9BrfZW9Izk9JSZYNigwUDwjrhNBSLr5NKi2A/LmZ0jjdCDkwaCn5io
+xrAq5oxPCAkwlzKwY2ootcL3+En4Pq2e5U+n9kRrpDpKKiR5/0S0d9vpgg4eZR0R
+kxqE9APCQ5SFU3PgnJ5H5y2SPXzle3bgUsWxNGD81zXFn5clJj4XHvJDWTQ/jG7C
+FTQ1o1HXtzda4EmKIzrSU/ayVbpPg5fPEBJjk/hHPT45kfzVZBuxwBLXVbe/YyWi
+NTFWCbJwjZwVRKrsQ3HFpYMWvugtcsSHo7vGi06FvUHcS2sUZH5sFn7hulcIGICt
+EztTO8Q+yhZujZbmEyJmxqZv
+-----END CERTIFICATE-----
-- 
2.20.1