From: Lee, Chun-Yi <joeyli.kernel@gmail.com>
Date: Tue, 13 Mar 2018 10:38:01 +0000 (+0800)
Subject: [PATCH 2/4] MODSIGN: load blacklist from MOKx
X-Git-Tag: archive/raspbian/5.7.6-1+rpi1^2~20
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=5a38918087bde4ed739aa2d601a2a9231125ce12;p=linux.git

[PATCH 2/4] MODSIGN: load blacklist from MOKx

Origin: https://lore.kernel.org/patchwork/patch/933177/

This patch adds the logic to load the blacklisted hash and
certificates from MOKx which is maintained by shim bootloader.

Cc: David Howells <dhowells@redhat.com>
Cc: Josh Boyer <jwboyer@fedoraproject.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: "Lee, Chun-Yi" <jlee@suse.com>
[Rebased by Luca Boccassi]
[bwh: Forward-ported to 5.5.9:
 - get_cert_list() takes a pointer to status and returns the cert list
 - Adjust filename]

Gbp-Pq: Topic features/all/db-mok-keyring
Gbp-Pq: Name 0002-MODSIGN-load-blacklist-from-MOKx.patch
---

diff --git a/security/integrity/platform_certs/load_uefi.c b/security/integrity/platform_certs/load_uefi.c
index 64909c0868f..4ed15ba1011 100644
--- a/security/integrity/platform_certs/load_uefi.c
+++ b/security/integrity/platform_certs/load_uefi.c
@@ -74,8 +74,8 @@ static int __init load_uefi_certs(void)
 {
 	efi_guid_t secure_var = EFI_IMAGE_SECURITY_DATABASE_GUID;
 	efi_guid_t mok_var = EFI_SHIM_LOCK_GUID;
-	void *db = NULL, *dbx = NULL, *mok = NULL;
-	unsigned long dbsize = 0, dbxsize = 0, moksize = 0;
+	void *db = NULL, *dbx = NULL, *mok = NULL, *mokx = NULL;
+	unsigned long dbsize = 0, dbxsize = 0, moksize = 0, mokxsize = 0;
 	efi_status_t status;
 	int rc = 0;
 
@@ -117,7 +117,7 @@ static int __init load_uefi_certs(void)
 		kfree(dbx);
 	}
 
-	/* the MOK can not be trusted when secure boot is disabled */
+	/* the MOK and MOKx can not be trusted when secure boot is disabled */
 	if (!efi_enabled(EFI_SECURE_BOOT))
 		return 0;
 
@@ -135,6 +135,21 @@ static int __init load_uefi_certs(void)
 		kfree(mok);
 	}
 
+	mokx = get_cert_list(L"MokListXRT", &mok_var, &mokxsize, &status);
+	if (!mokx) {
+		if (status == EFI_NOT_FOUND)
+			pr_debug("MokListXRT variable wasn't found\n");
+		else
+			pr_info("Couldn't get UEFI MokListXRT\n");
+	} else {
+		rc = parse_efi_signature_list("UEFI:mokx",
+					      mokx, mokxsize,
+					      get_handler_for_dbx);
+		if (rc)
+			pr_err("Couldn't parse MokListXRT signatures: %d\n", rc);
+		kfree(mokx);
+	}
+
 	return rc;
 }
 late_initcall(load_uefi_certs);