[PATCH RFC 10/12] integrity: add new keyring handler

From: Eric Snowberg
Date: Tue Jul 06 2021 - 22:45:49 EST


Add a new keyring handler for the mok keyring. If the Secondary trusted
keyring is enabled and the end-user trusts the MOK keys, this new
keyring handler is used.

Signed-off-by: Eric Snowberg <eric.snowberg@xxxxxxxxxx>
---
.../integrity/platform_certs/keyring_handler.c | 17 ++++++++++++++++-
.../integrity/platform_certs/keyring_handler.h | 5 +++++
security/integrity/platform_certs/load_uefi.c | 4 ++--
3 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/security/integrity/platform_certs/keyring_handler.c b/security/integrity/platform_certs/keyring_handler.c
index 5604bd57c990..b6daeb1e3de5 100644
--- a/security/integrity/platform_certs/keyring_handler.c
+++ b/security/integrity/platform_certs/keyring_handler.c
@@ -66,7 +66,7 @@ static __init void uefi_revocation_list_x509(const char *source,

/*
* Return the appropriate handler for particular signature list types found in
- * the UEFI db and MokListRT tables.
+ * the UEFI db tables.
*/
__init efi_element_handler_t get_handler_for_db(const efi_guid_t *sig_type)
{
@@ -75,6 +75,21 @@ __init efi_element_handler_t get_handler_for_db(const efi_guid_t *sig_type)
return 0;
}

+/*
+ * Return the appropriate handler for particular signature list types found in
+ * the MokListRT tables.
+ */
+__init efi_element_handler_t get_handler_for_mok(const efi_guid_t *sig_type)
+{
+ if (efi_guidcmp(*sig_type, efi_cert_x509_guid) == 0) {
+ if (IS_ENABLED(CONFIG_SECONDARY_TRUSTED_KEYRING) && trust_moklist())
+ return add_to_mok_keyring;
+ else
+ return add_to_platform_keyring;
+ }
+ return 0;
+}
+
/*
* Return the appropriate handler for particular signature list types found in
* the UEFI dbx and MokListXRT tables.
diff --git a/security/integrity/platform_certs/keyring_handler.h b/security/integrity/platform_certs/keyring_handler.h
index 2462bfa08fe3..284558f30411 100644
--- a/security/integrity/platform_certs/keyring_handler.h
+++ b/security/integrity/platform_certs/keyring_handler.h
@@ -24,6 +24,11 @@ void blacklist_binary(const char *source, const void *data, size_t len);
*/
efi_element_handler_t get_handler_for_db(const efi_guid_t *sig_type);

+/*
+ * Return the handler for particular signature list types found in the mok.
+ */
+efi_element_handler_t get_handler_for_mok(const efi_guid_t *sig_type);
+
/*
* Return the handler for particular signature list types found in the dbx.
*/
diff --git a/security/integrity/platform_certs/load_uefi.c b/security/integrity/platform_certs/load_uefi.c
index 94faa4b32441..f021dd81f080 100644
--- a/security/integrity/platform_certs/load_uefi.c
+++ b/security/integrity/platform_certs/load_uefi.c
@@ -94,7 +94,7 @@ static int __init load_moklist_certs(void)
rc = parse_efi_signature_list("UEFI:MokListRT (MOKvar table)",
mokvar_entry->data,
mokvar_entry->data_size,
- get_handler_for_db);
+ get_handler_for_mok);
/* All done if that worked. */
if (!rc)
return rc;
@@ -109,7 +109,7 @@ static int __init load_moklist_certs(void)
mok = get_cert_list(L"MokListRT", &mok_var, &moksize, &status);
if (mok) {
rc = parse_efi_signature_list("UEFI:MokListRT",
- mok, moksize, get_handler_for_db);
+ mok, moksize, get_handler_for_mok);
kfree(mok);
if (rc)
pr_err("Couldn't parse MokListRT signatures: %d\n", rc);
--
2.18.4