1387 lines
43 KiB
Diff
1387 lines
43 KiB
Diff
From 6f37ec98c44d2985746d3eeaea874ce6a684c0ac Mon Sep 17 00:00:00 2001
|
|
From: Matthew Garrett <mjg@redhat.com>
|
|
Date: Thu, 20 Sep 2012 10:40:56 -0400
|
|
Subject: [PATCH 01/18] Secure boot: Add new capability
|
|
|
|
Secure boot adds certain policy requirements, including that root must not
|
|
be able to do anything that could cause the kernel to execute arbitrary code.
|
|
The simplest way to handle this would seem to be to add a new capability
|
|
and gate various functionality on that. We'll then strip it from the initial
|
|
capability set if required.
|
|
|
|
Signed-off-by: Matthew Garrett <mjg@redhat.com>
|
|
---
|
|
include/uapi/linux/capability.h | 6 +++++-
|
|
1 file changed, 5 insertions(+), 1 deletion(-)
|
|
|
|
diff --git a/include/uapi/linux/capability.h b/include/uapi/linux/capability.h
|
|
index ba478fa..7109e65 100644
|
|
--- a/include/uapi/linux/capability.h
|
|
+++ b/include/uapi/linux/capability.h
|
|
@@ -343,7 +343,11 @@ struct vfs_cap_data {
|
|
|
|
#define CAP_BLOCK_SUSPEND 36
|
|
|
|
-#define CAP_LAST_CAP CAP_BLOCK_SUSPEND
|
|
+/* Allow things that trivially permit root to modify the running kernel */
|
|
+
|
|
+#define CAP_COMPROMISE_KERNEL 37
|
|
+
|
|
+#define CAP_LAST_CAP CAP_COMPROMISE_KERNEL
|
|
|
|
#define cap_valid(x) ((x) >= 0 && (x) <= CAP_LAST_CAP)
|
|
|
|
--
|
|
1.8.0.2
|
|
|
|
|
|
From 5a5dd529716bd36ea8f43e2a20dd8f80659f762a Mon Sep 17 00:00:00 2001
|
|
From: Josh Boyer <jwboyer@redhat.com>
|
|
Date: Thu, 20 Sep 2012 10:41:05 -0400
|
|
Subject: [PATCH 02/18] SELinux: define mapping for new Secure Boot capability
|
|
|
|
Add the name of the new Secure Boot capability. This allows SELinux
|
|
policies to properly map CAP_COMPROMISE_KERNEL to the appropriate
|
|
capability class.
|
|
|
|
Signed-off-by: Josh Boyer <jwboyer@redhat.com>
|
|
---
|
|
security/selinux/include/classmap.h | 4 ++--
|
|
1 file changed, 2 insertions(+), 2 deletions(-)
|
|
|
|
diff --git a/security/selinux/include/classmap.h b/security/selinux/include/classmap.h
|
|
index df2de54..70e2834 100644
|
|
--- a/security/selinux/include/classmap.h
|
|
+++ b/security/selinux/include/classmap.h
|
|
@@ -146,8 +146,8 @@ struct security_class_mapping secclass_map[] = {
|
|
{ "memprotect", { "mmap_zero", NULL } },
|
|
{ "peer", { "recv", NULL } },
|
|
{ "capability2",
|
|
- { "mac_override", "mac_admin", "syslog", "wake_alarm", "block_suspend",
|
|
- NULL } },
|
|
+ { "mac_override", "mac_admin", "syslog", "wake_alarm",
|
|
+ "block_suspend", "compromise_kernel", NULL } },
|
|
{ "kernel_service", { "use_as_override", "create_files_as", NULL } },
|
|
{ "tun_socket",
|
|
{ COMMON_SOCK_PERMS, NULL } },
|
|
--
|
|
1.8.0.2
|
|
|
|
|
|
From 891f2a956ba70b3d0b1acad3e235a3327f344d13 Mon Sep 17 00:00:00 2001
|
|
From: Josh Boyer <jwboyer@redhat.com>
|
|
Date: Thu, 20 Sep 2012 10:41:02 -0400
|
|
Subject: [PATCH 03/18] Secure boot: Add a dummy kernel parameter that will
|
|
switch on Secure Boot mode
|
|
|
|
This forcibly drops CAP_COMPROMISE_KERNEL from both cap_permitted and cap_bset
|
|
in the init_cred struct, which everything else inherits from. This works on
|
|
any machine and can be used to develop even if the box doesn't have UEFI.
|
|
|
|
Signed-off-by: Josh Boyer <jwboyer@redhat.com>
|
|
---
|
|
Documentation/kernel-parameters.txt | 7 +++++++
|
|
kernel/cred.c | 17 +++++++++++++++++
|
|
2 files changed, 24 insertions(+)
|
|
|
|
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
|
|
index 363e348..832b39b 100644
|
|
--- a/Documentation/kernel-parameters.txt
|
|
+++ b/Documentation/kernel-parameters.txt
|
|
@@ -2654,6 +2654,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
|
|
Note: increases power consumption, thus should only be
|
|
enabled if running jitter sensitive (HPC/RT) workloads.
|
|
|
|
+ secureboot_enable=
|
|
+ [KNL] Enables an emulated UEFI Secure Boot mode. This
|
|
+ locks down various aspects of the kernel guarded by the
|
|
+ CAP_COMPROMISE_KERNEL capability. This includes things
|
|
+ like /dev/mem, IO port access, and other areas. It can
|
|
+ be used on non-UEFI machines for testing purposes.
|
|
+
|
|
security= [SECURITY] Choose a security module to enable at boot.
|
|
If this boot parameter is not specified, only the first
|
|
security module asking for security registration will be
|
|
diff --git a/kernel/cred.c b/kernel/cred.c
|
|
index e0573a4..c3f4e3e 100644
|
|
--- a/kernel/cred.c
|
|
+++ b/kernel/cred.c
|
|
@@ -565,6 +565,23 @@ void __init cred_init(void)
|
|
0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
|
|
}
|
|
|
|
+void __init secureboot_enable()
|
|
+{
|
|
+ pr_info("Secure boot enabled\n");
|
|
+ cap_lower((&init_cred)->cap_bset, CAP_COMPROMISE_KERNEL);
|
|
+ cap_lower((&init_cred)->cap_permitted, CAP_COMPROMISE_KERNEL);
|
|
+}
|
|
+
|
|
+/* Dummy Secure Boot enable option to fake out UEFI SB=1 */
|
|
+static int __init secureboot_enable_opt(char *str)
|
|
+{
|
|
+ int sb_enable = !!simple_strtol(str, NULL, 0);
|
|
+ if (sb_enable)
|
|
+ secureboot_enable();
|
|
+ return 1;
|
|
+}
|
|
+__setup("secureboot_enable=", secureboot_enable_opt);
|
|
+
|
|
/**
|
|
* prepare_kernel_cred - Prepare a set of credentials for a kernel service
|
|
* @daemon: A userspace daemon to be used as a reference
|
|
--
|
|
1.8.0.2
|
|
|
|
|
|
From a98fc32f21318a7141552b6ef241407265fbecdd Mon Sep 17 00:00:00 2001
|
|
From: Matthew Garrett <mjg@redhat.com>
|
|
Date: Thu, 20 Sep 2012 10:41:03 -0400
|
|
Subject: [PATCH 04/18] efi: Enable secure boot lockdown automatically when
|
|
enabled in firmware
|
|
|
|
The firmware has a set of flags that indicate whether secure boot is enabled
|
|
and enforcing. Use them to indicate whether the kernel should lock itself
|
|
down.
|
|
|
|
Signed-off-by: Matthew Garrett <mjg@redhat.com>
|
|
---
|
|
Documentation/x86/zero-page.txt | 2 ++
|
|
arch/x86/boot/compressed/eboot.c | 32 ++++++++++++++++++++++++++++++++
|
|
arch/x86/include/uapi/asm/bootparam.h | 3 ++-
|
|
arch/x86/kernel/setup.c | 3 +++
|
|
include/linux/cred.h | 2 ++
|
|
5 files changed, 41 insertions(+), 1 deletion(-)
|
|
|
|
diff --git a/Documentation/x86/zero-page.txt b/Documentation/x86/zero-page.txt
|
|
index cf5437d..7f9ed48 100644
|
|
--- a/Documentation/x86/zero-page.txt
|
|
+++ b/Documentation/x86/zero-page.txt
|
|
@@ -27,6 +27,8 @@ Offset Proto Name Meaning
|
|
1E9/001 ALL eddbuf_entries Number of entries in eddbuf (below)
|
|
1EA/001 ALL edd_mbr_sig_buf_entries Number of entries in edd_mbr_sig_buffer
|
|
(below)
|
|
+1EB/001 ALL kbd_status Numlock is enabled
|
|
+1EC/001 ALL secure_boot Kernel should enable secure boot lockdowns
|
|
290/040 ALL edd_mbr_sig_buffer EDD MBR signatures
|
|
2D0/A00 ALL e820_map E820 memory map table
|
|
(array of struct e820entry)
|
|
diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
|
|
index b1942e2..1201907 100644
|
|
--- a/arch/x86/boot/compressed/eboot.c
|
|
+++ b/arch/x86/boot/compressed/eboot.c
|
|
@@ -848,6 +848,36 @@ fail:
|
|
return status;
|
|
}
|
|
|
|
+static int get_secure_boot(efi_system_table_t *_table)
|
|
+{
|
|
+ u8 sb, setup;
|
|
+ unsigned long datasize = sizeof(sb);
|
|
+ efi_guid_t var_guid = EFI_GLOBAL_VARIABLE_GUID;
|
|
+ efi_status_t status;
|
|
+
|
|
+ status = efi_call_phys5(sys_table->runtime->get_variable,
|
|
+ L"SecureBoot", &var_guid, NULL, &datasize, &sb);
|
|
+
|
|
+ if (status != EFI_SUCCESS)
|
|
+ return 0;
|
|
+
|
|
+ if (sb == 0)
|
|
+ return 0;
|
|
+
|
|
+
|
|
+ status = efi_call_phys5(sys_table->runtime->get_variable,
|
|
+ L"SetupMode", &var_guid, NULL, &datasize,
|
|
+ &setup);
|
|
+
|
|
+ if (status != EFI_SUCCESS)
|
|
+ return 0;
|
|
+
|
|
+ if (setup == 1)
|
|
+ return 0;
|
|
+
|
|
+ return 1;
|
|
+}
|
|
+
|
|
/*
|
|
* Because the x86 boot code expects to be passed a boot_params we
|
|
* need to create one ourselves (usually the bootloader would create
|
|
@@ -1142,6 +1172,8 @@ struct boot_params *efi_main(void *handle, efi_system_table_t *_table,
|
|
if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
|
|
goto fail;
|
|
|
|
+ boot_params->secure_boot = get_secure_boot(sys_table);
|
|
+
|
|
setup_graphics(boot_params);
|
|
|
|
setup_efi_pci(boot_params);
|
|
diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h
|
|
index 92862cd..422e056 100644
|
|
--- a/arch/x86/include/uapi/asm/bootparam.h
|
|
+++ b/arch/x86/include/uapi/asm/bootparam.h
|
|
@@ -115,7 +115,8 @@ struct boot_params {
|
|
__u8 eddbuf_entries; /* 0x1e9 */
|
|
__u8 edd_mbr_sig_buf_entries; /* 0x1ea */
|
|
__u8 kbd_status; /* 0x1eb */
|
|
- __u8 _pad6[5]; /* 0x1ec */
|
|
+ __u8 secure_boot; /* 0x1ec */
|
|
+ __u8 _pad6[4]; /* 0x1ed */
|
|
struct setup_header hdr; /* setup header */ /* 0x1f1 */
|
|
__u8 _pad7[0x290-0x1f1-sizeof(struct setup_header)];
|
|
__u32 edd_mbr_sig_buffer[EDD_MBR_SIG_MAX]; /* 0x290 */
|
|
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
|
|
index 23ddd55..94203e5 100644
|
|
--- a/arch/x86/kernel/setup.c
|
|
+++ b/arch/x86/kernel/setup.c
|
|
@@ -962,6 +962,9 @@ void __init setup_arch(char **cmdline_p)
|
|
|
|
io_delay_init();
|
|
|
|
+ if (boot_params.secure_boot)
|
|
+ secureboot_enable();
|
|
+
|
|
/*
|
|
* Parse the ACPI tables for possible boot-time SMP configuration.
|
|
*/
|
|
diff --git a/include/linux/cred.h b/include/linux/cred.h
|
|
index 04421e8..9e69542 100644
|
|
--- a/include/linux/cred.h
|
|
+++ b/include/linux/cred.h
|
|
@@ -156,6 +156,8 @@ extern int set_security_override_from_ctx(struct cred *, const char *);
|
|
extern int set_create_files_as(struct cred *, struct inode *);
|
|
extern void __init cred_init(void);
|
|
|
|
+extern void secureboot_enable(void);
|
|
+
|
|
/*
|
|
* check for validity of credentials
|
|
*/
|
|
--
|
|
1.8.0.2
|
|
|
|
|
|
From 4a5cc45467da5652b19ac27e409761c79efd56f1 Mon Sep 17 00:00:00 2001
|
|
From: Josh Boyer <jwboyer@redhat.com>
|
|
Date: Fri, 26 Oct 2012 12:29:49 -0400
|
|
Subject: [PATCH 05/18] EFI: Add in-kernel variable to determine if Secure Boot
|
|
is enabled
|
|
|
|
There are a few cases where in-kernel functions may need to know if
|
|
Secure Boot is enabled. The added capability check cannot be used as the
|
|
kernel can't drop it's own capabilites, so we add a global variable
|
|
similar to efi_enabled so they can determine if Secure Boot is enabled.
|
|
|
|
Signed-off-by: Josh Boyer <jwboyer@redhat.com>
|
|
---
|
|
arch/x86/kernel/setup.c | 6 +++++-
|
|
arch/x86/platform/efi/efi.c | 2 ++
|
|
include/linux/efi.h | 3 +++
|
|
3 files changed, 10 insertions(+), 1 deletion(-)
|
|
|
|
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
|
|
index 94203e5..2b89b38 100644
|
|
--- a/arch/x86/kernel/setup.c
|
|
+++ b/arch/x86/kernel/setup.c
|
|
@@ -962,8 +962,12 @@ void __init setup_arch(char **cmdline_p)
|
|
|
|
io_delay_init();
|
|
|
|
- if (boot_params.secure_boot)
|
|
+ if (boot_params.secure_boot) {
|
|
secureboot_enable();
|
|
+#ifdef CONFIG_EFI
|
|
+ secure_boot_enabled = 1;
|
|
+#endif
|
|
+ }
|
|
|
|
/*
|
|
* Parse the ACPI tables for possible boot-time SMP configuration.
|
|
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
|
|
index ad44391..d22bfeb 100644
|
|
--- a/arch/x86/platform/efi/efi.c
|
|
+++ b/arch/x86/platform/efi/efi.c
|
|
@@ -54,6 +54,8 @@
|
|
int efi_enabled;
|
|
EXPORT_SYMBOL(efi_enabled);
|
|
|
|
+int secure_boot_enabled;
|
|
+
|
|
struct efi __read_mostly efi = {
|
|
.mps = EFI_INVALID_TABLE_ADDR,
|
|
.acpi = EFI_INVALID_TABLE_ADDR,
|
|
diff --git a/include/linux/efi.h b/include/linux/efi.h
|
|
index 8b84916..7a1a53c 100644
|
|
--- a/include/linux/efi.h
|
|
+++ b/include/linux/efi.h
|
|
@@ -625,11 +625,14 @@ extern int __init efi_setup_pcdp_console(char *);
|
|
# ifdef CONFIG_X86
|
|
extern int efi_enabled;
|
|
extern bool efi_64bit;
|
|
+ extern int secure_boot_enabled;
|
|
# else
|
|
# define efi_enabled 1
|
|
+# define secure_boot_enabled 0
|
|
# endif
|
|
#else
|
|
# define efi_enabled 0
|
|
+# define secure_boot_enabled 0
|
|
#endif
|
|
|
|
/*
|
|
--
|
|
1.8.0.2
|
|
|
|
|
|
From 34c2022a3b9cc4e064fe85d0ebc83b38bd6315d3 Mon Sep 17 00:00:00 2001
|
|
From: Dave Howells <dhowells@redhat.com>
|
|
Date: Tue, 23 Oct 2012 09:30:54 -0400
|
|
Subject: [PATCH 06/18] Add EFI signature data types
|
|
|
|
Add the data types that are used for containing hashes, keys and certificates
|
|
for cryptographic verification.
|
|
|
|
Signed-off-by: David Howells <dhowells@redhat.com>
|
|
---
|
|
include/linux/efi.h | 20 ++++++++++++++++++++
|
|
1 file changed, 20 insertions(+)
|
|
|
|
diff --git a/include/linux/efi.h b/include/linux/efi.h
|
|
index 7a1a53c..887b9f3 100644
|
|
--- a/include/linux/efi.h
|
|
+++ b/include/linux/efi.h
|
|
@@ -388,6 +388,12 @@ typedef efi_status_t efi_query_capsule_caps_t(efi_capsule_header_t **capsules,
|
|
#define EFI_FILE_SYSTEM_GUID \
|
|
EFI_GUID( 0x964e5b22, 0x6459, 0x11d2, 0x8e, 0x39, 0x00, 0xa0, 0xc9, 0x69, 0x72, 0x3b )
|
|
|
|
+#define EFI_CERT_SHA256_GUID \
|
|
+ EFI_GUID( 0xc1c41626, 0x504c, 0x4092, 0xac, 0xa9, 0x41, 0xf9, 0x36, 0x93, 0x43, 0x28 )
|
|
+
|
|
+#define EFI_CERT_X509_GUID \
|
|
+ EFI_GUID( 0xa5c059a1, 0x94e4, 0x4aa7, 0x87, 0xb5, 0xab, 0x15, 0x5c, 0x2b, 0xf0, 0x72 )
|
|
+
|
|
typedef struct {
|
|
efi_guid_t guid;
|
|
u64 table;
|
|
@@ -523,6 +529,20 @@ typedef struct {
|
|
|
|
#define EFI_INVALID_TABLE_ADDR (~0UL)
|
|
|
|
+typedef struct {
|
|
+ efi_guid_t signature_owner;
|
|
+ u8 signature_data[];
|
|
+} efi_signature_data_t;
|
|
+
|
|
+typedef struct {
|
|
+ efi_guid_t signature_type;
|
|
+ u32 signature_list_size;
|
|
+ u32 signature_header_size;
|
|
+ u32 signature_size;
|
|
+ u8 signature_header[];
|
|
+ /* efi_signature_data_t signatures[][] */
|
|
+} efi_signature_list_t;
|
|
+
|
|
/*
|
|
* All runtime access to EFI goes through this structure:
|
|
*/
|
|
--
|
|
1.8.0.2
|
|
|
|
|
|
From 13ed8f224caf51355124ceb154dd2cd1559b85d9 Mon Sep 17 00:00:00 2001
|
|
From: Dave Howells <dhowells@redhat.com>
|
|
Date: Tue, 23 Oct 2012 09:36:28 -0400
|
|
Subject: [PATCH 07/18] Add an EFI signature blob parser and key loader.
|
|
|
|
X.509 certificates are loaded into the specified keyring as asymmetric type
|
|
keys.
|
|
|
|
Signed-off-by: David Howells <dhowells@redhat.com>
|
|
---
|
|
crypto/asymmetric_keys/Kconfig | 8 +++
|
|
crypto/asymmetric_keys/Makefile | 1 +
|
|
crypto/asymmetric_keys/efi_parser.c | 108 ++++++++++++++++++++++++++++++++++++
|
|
include/linux/efi.h | 4 ++
|
|
4 files changed, 121 insertions(+)
|
|
create mode 100644 crypto/asymmetric_keys/efi_parser.c
|
|
|
|
diff --git a/crypto/asymmetric_keys/Kconfig b/crypto/asymmetric_keys/Kconfig
|
|
index 6d2c2ea..ace9c30 100644
|
|
--- a/crypto/asymmetric_keys/Kconfig
|
|
+++ b/crypto/asymmetric_keys/Kconfig
|
|
@@ -35,4 +35,12 @@ config X509_CERTIFICATE_PARSER
|
|
data and provides the ability to instantiate a crypto key from a
|
|
public key packet found inside the certificate.
|
|
|
|
+config EFI_SIGNATURE_LIST_PARSER
|
|
+ bool "EFI signature list parser"
|
|
+ depends on EFI
|
|
+ select X509_CERTIFICATE_PARSER
|
|
+ help
|
|
+ This option provides support for parsing EFI signature lists for
|
|
+ X.509 certificates and turning them into keys.
|
|
+
|
|
endif # ASYMMETRIC_KEY_TYPE
|
|
diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile
|
|
index 0727204..cd8388e 100644
|
|
--- a/crypto/asymmetric_keys/Makefile
|
|
+++ b/crypto/asymmetric_keys/Makefile
|
|
@@ -8,6 +8,7 @@ asymmetric_keys-y := asymmetric_type.o signature.o
|
|
|
|
obj-$(CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE) += public_key.o
|
|
obj-$(CONFIG_PUBLIC_KEY_ALGO_RSA) += rsa.o
|
|
+obj-$(CONFIG_EFI_SIGNATURE_LIST_PARSER) += efi_parser.o
|
|
|
|
#
|
|
# X.509 Certificate handling
|
|
diff --git a/crypto/asymmetric_keys/efi_parser.c b/crypto/asymmetric_keys/efi_parser.c
|
|
new file mode 100644
|
|
index 0000000..636feb1
|
|
--- /dev/null
|
|
+++ b/crypto/asymmetric_keys/efi_parser.c
|
|
@@ -0,0 +1,108 @@
|
|
+/* EFI signature/key/certificate list parser
|
|
+ *
|
|
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
|
|
+ * Written by David Howells (dhowells@redhat.com)
|
|
+ *
|
|
+ * This program is free software; you can redistribute it and/or
|
|
+ * modify it under the terms of the GNU General Public Licence
|
|
+ * as published by the Free Software Foundation; either version
|
|
+ * 2 of the Licence, or (at your option) any later version.
|
|
+ */
|
|
+
|
|
+#define pr_fmt(fmt) "EFI: "fmt
|
|
+#include <linux/module.h>
|
|
+#include <linux/printk.h>
|
|
+#include <linux/err.h>
|
|
+#include <linux/efi.h>
|
|
+#include <keys/asymmetric-type.h>
|
|
+
|
|
+static __initdata efi_guid_t efi_cert_x509_guid = EFI_CERT_X509_GUID;
|
|
+
|
|
+/**
|
|
+ * parse_efi_signature_list - Parse an EFI signature list for certificates
|
|
+ * @data: The data blob to parse
|
|
+ * @size: The size of the data blob
|
|
+ * @keyring: The keyring to add extracted keys to
|
|
+ */
|
|
+int __init parse_efi_signature_list(const void *data, size_t size, struct key *keyring)
|
|
+{
|
|
+ unsigned offs = 0;
|
|
+ size_t lsize, esize, hsize, elsize;
|
|
+
|
|
+ pr_devel("-->%s(,%zu)\n", __func__, size);
|
|
+
|
|
+ while (size > 0) {
|
|
+ efi_signature_list_t list;
|
|
+ const efi_signature_data_t *elem;
|
|
+ key_ref_t key;
|
|
+
|
|
+ if (size < sizeof(list))
|
|
+ return -EBADMSG;
|
|
+
|
|
+ memcpy(&list, data, sizeof(list));
|
|
+ pr_devel("LIST[%04x] guid=%pUl ls=%x hs=%x ss=%x\n",
|
|
+ offs,
|
|
+ list.signature_type.b, list.signature_list_size,
|
|
+ list.signature_header_size, list.signature_size);
|
|
+
|
|
+ lsize = list.signature_list_size;
|
|
+ hsize = list.signature_header_size;
|
|
+ esize = list.signature_size;
|
|
+ elsize = lsize - sizeof(list) - hsize;
|
|
+
|
|
+ if (lsize > size) {
|
|
+ pr_devel("<--%s() = -EBADMSG [overrun @%x]\n",
|
|
+ __func__, offs);
|
|
+ return -EBADMSG;
|
|
+ }
|
|
+ if (lsize < sizeof(list) ||
|
|
+ lsize - sizeof(list) < hsize ||
|
|
+ esize < sizeof(*elem) ||
|
|
+ elsize < esize ||
|
|
+ elsize % esize != 0) {
|
|
+ pr_devel("- bad size combo @%x\n", offs);
|
|
+ return -EBADMSG;
|
|
+ }
|
|
+
|
|
+ if (efi_guidcmp(list.signature_type, efi_cert_x509_guid) != 0) {
|
|
+ data += lsize;
|
|
+ size -= lsize;
|
|
+ offs += lsize;
|
|
+ continue;
|
|
+ }
|
|
+
|
|
+ data += sizeof(list) + hsize;
|
|
+ size -= sizeof(list) + hsize;
|
|
+ offs += sizeof(list) + hsize;
|
|
+
|
|
+ for (; elsize > 0; elsize -= esize) {
|
|
+ elem = data;
|
|
+
|
|
+ pr_devel("ELEM[%04x]\n", offs);
|
|
+
|
|
+ key = key_create_or_update(
|
|
+ make_key_ref(keyring, 1),
|
|
+ "asymmetric",
|
|
+ NULL,
|
|
+ &elem->signature_data,
|
|
+ esize - sizeof(*elem),
|
|
+ (KEY_POS_ALL & ~KEY_POS_SETATTR) |
|
|
+ KEY_USR_VIEW,
|
|
+ KEY_ALLOC_NOT_IN_QUOTA);
|
|
+
|
|
+ if (IS_ERR(key))
|
|
+ pr_err("Problem loading in-kernel X.509 certificate (%ld)\n",
|
|
+ PTR_ERR(key));
|
|
+ else
|
|
+ pr_notice("Loaded cert '%s' linked to '%s'\n",
|
|
+ key_ref_to_ptr(key)->description,
|
|
+ keyring->description);
|
|
+
|
|
+ data += esize;
|
|
+ size -= esize;
|
|
+ offs += esize;
|
|
+ }
|
|
+ }
|
|
+
|
|
+ return 0;
|
|
+}
|
|
diff --git a/include/linux/efi.h b/include/linux/efi.h
|
|
index 887b9f3..6b78779 100644
|
|
--- a/include/linux/efi.h
|
|
+++ b/include/linux/efi.h
|
|
@@ -612,6 +612,10 @@ extern int efi_set_rtc_mmss(unsigned long nowtime);
|
|
extern void efi_reserve_boot_services(void);
|
|
extern struct efi_memory_map memmap;
|
|
|
|
+struct key;
|
|
+extern int __init parse_efi_signature_list(const void *data, size_t size,
|
|
+ struct key *keyring);
|
|
+
|
|
/**
|
|
* efi_range_is_wc - check the WC bit on an address range
|
|
* @start: starting kvirt address
|
|
--
|
|
1.8.0.2
|
|
|
|
|
|
From 8d89c8b4cc5869044f4ed78358b7d8a93f11cfac Mon Sep 17 00:00:00 2001
|
|
From: Josh Boyer <jwboyer@redhat.com>
|
|
Date: Fri, 26 Oct 2012 12:36:24 -0400
|
|
Subject: [PATCH 08/18] MODSIGN: Add module certificate blacklist keyring
|
|
|
|
This adds an additional keyring that is used to store certificates that
|
|
are blacklisted. This keyring is searched first when loading signed modules
|
|
and if the module's certificate is found, it will refuse to load. This is
|
|
useful in cases where third party certificates are used for module signing.
|
|
|
|
Signed-off-by: Josh Boyer <jwboyer@redhat.com>
|
|
---
|
|
init/Kconfig | 8 ++++++++
|
|
kernel/modsign_pubkey.c | 14 ++++++++++++++
|
|
kernel/module-internal.h | 3 +++
|
|
kernel/module_signing.c | 12 ++++++++++++
|
|
4 files changed, 37 insertions(+)
|
|
|
|
diff --git a/init/Kconfig b/init/Kconfig
|
|
index 7d30240..4a0705e 100644
|
|
--- a/init/Kconfig
|
|
+++ b/init/Kconfig
|
|
@@ -1665,6 +1665,14 @@ config MODULE_SIG_FORCE
|
|
Reject unsigned modules or signed modules for which we don't have a
|
|
key. Without this, such modules will simply taint the kernel.
|
|
|
|
+config MODULE_SIG_BLACKLIST
|
|
+ bool "Support for blacklisting module signature certificates"
|
|
+ depends on MODULE_SIG
|
|
+ help
|
|
+ This adds support for keeping a blacklist of certificates that
|
|
+ should not pass module signature verification. If a module is
|
|
+ signed with something in this keyring, the load will be rejected.
|
|
+
|
|
choice
|
|
prompt "Which hash algorithm should modules be signed with?"
|
|
depends on MODULE_SIG
|
|
diff --git a/kernel/modsign_pubkey.c b/kernel/modsign_pubkey.c
|
|
index 2b6e699..4cd408d 100644
|
|
--- a/kernel/modsign_pubkey.c
|
|
+++ b/kernel/modsign_pubkey.c
|
|
@@ -17,6 +17,9 @@
|
|
#include "module-internal.h"
|
|
|
|
struct key *modsign_keyring;
|
|
+#ifdef CONFIG_MODULE_SIG_BLACKLIST
|
|
+struct key *modsign_blacklist;
|
|
+#endif
|
|
|
|
extern __initdata const u8 modsign_certificate_list[];
|
|
extern __initdata const u8 modsign_certificate_list_end[];
|
|
@@ -43,6 +46,17 @@ static __init int module_verify_init(void)
|
|
if (IS_ERR(modsign_keyring))
|
|
panic("Can't allocate module signing keyring\n");
|
|
|
|
+#ifdef CONFIG_MODULE_SIG_BLACKLIST
|
|
+ modsign_blacklist = keyring_alloc(".modsign_blacklist",
|
|
+ KUIDT_INIT(0), KGIDT_INIT(0),
|
|
+ current_cred(),
|
|
+ (KEY_POS_ALL & ~KEY_POS_SETATTR) |
|
|
+ KEY_USR_VIEW | KEY_USR_READ,
|
|
+ KEY_ALLOC_NOT_IN_QUOTA, NULL);
|
|
+ if (IS_ERR(modsign_blacklist))
|
|
+ panic("Can't allocate module signing blacklist keyring\n");
|
|
+#endif
|
|
+
|
|
return 0;
|
|
}
|
|
|
|
diff --git a/kernel/module-internal.h b/kernel/module-internal.h
|
|
index 24f9247..51a8380 100644
|
|
--- a/kernel/module-internal.h
|
|
+++ b/kernel/module-internal.h
|
|
@@ -10,5 +10,8 @@
|
|
*/
|
|
|
|
extern struct key *modsign_keyring;
|
|
+#ifdef CONFIG_MODULE_SIG_BLACKLIST
|
|
+extern struct key *modsign_blacklist;
|
|
+#endif
|
|
|
|
extern int mod_verify_sig(const void *mod, unsigned long *_modlen);
|
|
diff --git a/kernel/module_signing.c b/kernel/module_signing.c
|
|
index f2970bd..5423195 100644
|
|
--- a/kernel/module_signing.c
|
|
+++ b/kernel/module_signing.c
|
|
@@ -157,6 +157,18 @@ static struct key *request_asymmetric_key(const char *signer, size_t signer_len,
|
|
|
|
pr_debug("Look up: \"%s\"\n", id);
|
|
|
|
+#ifdef CONFIG_MODULE_SIG_BLACKLIST
|
|
+ key = keyring_search(make_key_ref(modsign_blacklist, 1),
|
|
+ &key_type_asymmetric, id);
|
|
+ if (!IS_ERR(key)) {
|
|
+ /* module is signed with a cert in the blacklist. reject */
|
|
+ pr_err("Module key '%s' is in blacklist\n", id);
|
|
+ key_ref_put(key);
|
|
+ kfree(id);
|
|
+ return ERR_PTR(-EKEYREJECTED);
|
|
+ }
|
|
+#endif
|
|
+
|
|
key = keyring_search(make_key_ref(modsign_keyring, 1),
|
|
&key_type_asymmetric, id);
|
|
if (IS_ERR(key))
|
|
--
|
|
1.8.0.2
|
|
|
|
|
|
From e4663a7c5ef224c9fb0fa74ba42f3f9c52f8ca30 Mon Sep 17 00:00:00 2001
|
|
From: Josh Boyer <jwboyer@redhat.com>
|
|
Date: Fri, 26 Oct 2012 12:42:16 -0400
|
|
Subject: [PATCH 09/18] MODSIGN: Import certificates from UEFI Secure Boot
|
|
|
|
Secure Boot stores a list of allowed certificates in the 'db' variable.
|
|
This imports those certificates into the module signing keyring. This
|
|
allows for a third party signing certificate to be used in conjunction
|
|
with signed modules. By importing the public certificate into the 'db'
|
|
variable, a user can allow a module signed with that certificate to
|
|
load. The shim UEFI bootloader has a similar certificate list stored
|
|
in the 'MokListRT' variable. We import those as well.
|
|
|
|
In the opposite case, Secure Boot maintains a list of disallowed
|
|
certificates in the 'dbx' variable. We load those certificates into
|
|
the newly introduced module blacklist keyring and forbid any module
|
|
signed with those from loading.
|
|
|
|
Signed-off-by: Josh Boyer <jwboyer@redhat.com>
|
|
---
|
|
include/linux/efi.h | 6 ++++
|
|
init/Kconfig | 9 ++++++
|
|
kernel/Makefile | 3 ++
|
|
kernel/modsign_uefi.c | 90 +++++++++++++++++++++++++++++++++++++++++++++++++++
|
|
4 files changed, 108 insertions(+)
|
|
create mode 100644 kernel/modsign_uefi.c
|
|
|
|
diff --git a/include/linux/efi.h b/include/linux/efi.h
|
|
index 6b78779..a395dff 100644
|
|
--- a/include/linux/efi.h
|
|
+++ b/include/linux/efi.h
|
|
@@ -394,6 +394,12 @@ typedef efi_status_t efi_query_capsule_caps_t(efi_capsule_header_t **capsules,
|
|
#define EFI_CERT_X509_GUID \
|
|
EFI_GUID( 0xa5c059a1, 0x94e4, 0x4aa7, 0x87, 0xb5, 0xab, 0x15, 0x5c, 0x2b, 0xf0, 0x72 )
|
|
|
|
+#define EFI_IMAGE_SECURITY_DATABASE_GUID \
|
|
+ EFI_GUID( 0xd719b2cb, 0x3d3a, 0x4596, 0xa3, 0xbc, 0xda, 0xd0, 0x0e, 0x67, 0x65, 0x6f )
|
|
+
|
|
+#define EFI_SHIM_LOCK_GUID \
|
|
+ EFI_GUID( 0x605dab50, 0xe046, 0x4300, 0xab, 0xb6, 0x3d, 0xd8, 0x10, 0xdd, 0x8b, 0x23 )
|
|
+
|
|
typedef struct {
|
|
efi_guid_t guid;
|
|
u64 table;
|
|
diff --git a/init/Kconfig b/init/Kconfig
|
|
index 4a0705e..984b316 100644
|
|
--- a/init/Kconfig
|
|
+++ b/init/Kconfig
|
|
@@ -1673,6 +1673,15 @@ config MODULE_SIG_BLACKLIST
|
|
should not pass module signature verification. If a module is
|
|
signed with something in this keyring, the load will be rejected.
|
|
|
|
+config MODULE_SIG_UEFI
|
|
+ bool "Allow modules signed with certs stored in UEFI"
|
|
+ depends on MODULE_SIG && MODULE_SIG_BLACKLIST && EFI
|
|
+ select EFI_SIGNATURE_LIST_PARSER
|
|
+ help
|
|
+ This will import certificates stored in UEFI and allow modules
|
|
+ signed with those to be loaded. It will also disallow loading
|
|
+ of modules stored in the UEFI dbx variable.
|
|
+
|
|
choice
|
|
prompt "Which hash algorithm should modules be signed with?"
|
|
depends on MODULE_SIG
|
|
diff --git a/kernel/Makefile b/kernel/Makefile
|
|
index 6c072b6..8848829 100644
|
|
--- a/kernel/Makefile
|
|
+++ b/kernel/Makefile
|
|
@@ -55,6 +55,7 @@ obj-$(CONFIG_PROVE_LOCKING) += spinlock.o
|
|
obj-$(CONFIG_UID16) += uid16.o
|
|
obj-$(CONFIG_MODULES) += module.o
|
|
obj-$(CONFIG_MODULE_SIG) += module_signing.o modsign_pubkey.o modsign_certificate.o
|
|
+obj-$(CONFIG_MODULE_SIG_UEFI) += modsign_uefi.o
|
|
obj-$(CONFIG_KALLSYMS) += kallsyms.o
|
|
obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o
|
|
obj-$(CONFIG_KEXEC) += kexec.o
|
|
@@ -114,6 +115,8 @@ obj-$(CONFIG_CONTEXT_TRACKING) += context_tracking.o
|
|
|
|
$(obj)/configs.o: $(obj)/config_data.h
|
|
|
|
+$(obj)/modsign_uefi.o: KBUILD_CFLAGS += -fshort-wchar
|
|
+
|
|
# config_data.h contains the same information as ikconfig.h but gzipped.
|
|
# Info from config_data can be extracted from /proc/config*
|
|
targets += config_data.gz
|
|
diff --git a/kernel/modsign_uefi.c b/kernel/modsign_uefi.c
|
|
new file mode 100644
|
|
index 0000000..76a5a34
|
|
--- /dev/null
|
|
+++ b/kernel/modsign_uefi.c
|
|
@@ -0,0 +1,90 @@
|
|
+#include <linux/kernel.h>
|
|
+#include <linux/sched.h>
|
|
+#include <linux/cred.h>
|
|
+#include <linux/err.h>
|
|
+#include <linux/efi.h>
|
|
+#include <keys/asymmetric-type.h>
|
|
+#include "module-internal.h"
|
|
+
|
|
+static __init void *get_cert_list(efi_char16_t *name, efi_guid_t *guid, unsigned long *size)
|
|
+{
|
|
+ efi_status_t status;
|
|
+ unsigned long lsize = 4;
|
|
+ unsigned long tmpdb[4];
|
|
+ void *db = NULL;
|
|
+
|
|
+ status = efi.get_variable(name, guid, NULL, &lsize, &tmpdb);
|
|
+ if (status != EFI_BUFFER_TOO_SMALL) {
|
|
+ pr_err("Couldn't get size: 0x%lx\n", status);
|
|
+ return NULL;
|
|
+ }
|
|
+
|
|
+ db = kmalloc(lsize, GFP_KERNEL);
|
|
+ if (!db) {
|
|
+ pr_err("Couldn't allocate memory for uefi cert list\n");
|
|
+ goto out;
|
|
+ }
|
|
+
|
|
+ status = efi.get_variable(name, guid, NULL, &lsize, db);
|
|
+ if (status != EFI_SUCCESS) {
|
|
+ kfree(db);
|
|
+ db = NULL;
|
|
+ pr_err("Error reading db var: 0x%lx\n", status);
|
|
+ }
|
|
+out:
|
|
+ *size = lsize;
|
|
+ return db;
|
|
+}
|
|
+
|
|
+/*
|
|
+ * * Load the certs contained in the UEFI databases
|
|
+ * */
|
|
+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;
|
|
+ int rc = 0;
|
|
+
|
|
+ /* Check if SB is enabled and just return if not */
|
|
+ if (!secure_boot_enabled)
|
|
+ return 0;
|
|
+
|
|
+ /* Get db, MokListRT, and dbx. They might not exist, so it isn't
|
|
+ * an error if we can't get them.
|
|
+ */
|
|
+ db = get_cert_list(L"db", &secure_var, &dbsize);
|
|
+ if (!db) {
|
|
+ pr_err("MODSIGN: Couldn't get UEFI db list\n");
|
|
+ } else {
|
|
+ rc = parse_efi_signature_list(db, dbsize, modsign_keyring);
|
|
+ if (rc)
|
|
+ pr_err("Couldn't parse db signatures: %d\n", rc);
|
|
+ kfree(db);
|
|
+ }
|
|
+
|
|
+ mok = get_cert_list(L"MokListRT", &mok_var, &moksize);
|
|
+ if (!mok) {
|
|
+ pr_info("MODSIGN: Couldn't get UEFI MokListRT\n");
|
|
+ } else {
|
|
+ rc = parse_efi_signature_list(mok, moksize, modsign_keyring);
|
|
+ if (rc)
|
|
+ pr_err("Couldn't parse MokListRT signatures: %d\n", rc);
|
|
+ kfree(mok);
|
|
+ }
|
|
+
|
|
+ dbx = get_cert_list(L"dbx", &secure_var, &dbxsize);
|
|
+ if (!dbx) {
|
|
+ pr_info("MODSIGN: Couldn't get UEFI dbx list\n");
|
|
+ } else {
|
|
+ rc = parse_efi_signature_list(dbx, dbxsize,
|
|
+ modsign_blacklist);
|
|
+ if (rc)
|
|
+ pr_err("Couldn't parse dbx signatures: %d\n", rc);
|
|
+ kfree(dbx);
|
|
+ }
|
|
+
|
|
+ return rc;
|
|
+}
|
|
+late_initcall(load_uefi_certs);
|
|
--
|
|
1.8.0.2
|
|
|
|
|
|
From 798940ec4bc3826ef74e985cd021fc7e3db6eae7 Mon Sep 17 00:00:00 2001
|
|
From: Matthew Garrett <mjg@redhat.com>
|
|
Date: Thu, 20 Sep 2012 10:40:57 -0400
|
|
Subject: [PATCH 10/18] PCI: Lock down BAR access in secure boot environments
|
|
|
|
Any hardware that can potentially generate DMA has to be locked down from
|
|
userspace in order to avoid it being possible for an attacker to cause
|
|
arbitrary kernel behaviour. Default to paranoid - in future we can
|
|
potentially relax this for sufficiently IOMMU-isolated devices.
|
|
|
|
Signed-off-by: Matthew Garrett <mjg@redhat.com>
|
|
---
|
|
drivers/pci/pci-sysfs.c | 9 +++++++++
|
|
drivers/pci/proc.c | 8 +++++++-
|
|
drivers/pci/syscall.c | 2 +-
|
|
3 files changed, 17 insertions(+), 2 deletions(-)
|
|
|
|
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
|
|
index 9c6e9bb..b966089 100644
|
|
--- a/drivers/pci/pci-sysfs.c
|
|
+++ b/drivers/pci/pci-sysfs.c
|
|
@@ -622,6 +622,9 @@ pci_write_config(struct file* filp, struct kobject *kobj,
|
|
loff_t init_off = off;
|
|
u8 *data = (u8*) buf;
|
|
|
|
+ if (!capable(CAP_COMPROMISE_KERNEL))
|
|
+ return -EPERM;
|
|
+
|
|
if (off > dev->cfg_size)
|
|
return 0;
|
|
if (off + count > dev->cfg_size) {
|
|
@@ -928,6 +931,9 @@ pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr,
|
|
resource_size_t start, end;
|
|
int i;
|
|
|
|
+ if (!capable(CAP_COMPROMISE_KERNEL))
|
|
+ return -EPERM;
|
|
+
|
|
for (i = 0; i < PCI_ROM_RESOURCE; i++)
|
|
if (res == &pdev->resource[i])
|
|
break;
|
|
@@ -1035,6 +1041,9 @@ pci_write_resource_io(struct file *filp, struct kobject *kobj,
|
|
struct bin_attribute *attr, char *buf,
|
|
loff_t off, size_t count)
|
|
{
|
|
+ if (!capable(CAP_COMPROMISE_KERNEL))
|
|
+ return -EPERM;
|
|
+
|
|
return pci_resource_io(filp, kobj, attr, buf, off, count, true);
|
|
}
|
|
|
|
diff --git a/drivers/pci/proc.c b/drivers/pci/proc.c
|
|
index 9b8505c..35580bc 100644
|
|
--- a/drivers/pci/proc.c
|
|
+++ b/drivers/pci/proc.c
|
|
@@ -139,6 +139,9 @@ proc_bus_pci_write(struct file *file, const char __user *buf, size_t nbytes, lof
|
|
int size = dp->size;
|
|
int cnt;
|
|
|
|
+ if (!capable(CAP_COMPROMISE_KERNEL))
|
|
+ return -EPERM;
|
|
+
|
|
if (pos >= size)
|
|
return 0;
|
|
if (nbytes >= size)
|
|
@@ -219,6 +222,9 @@ static long proc_bus_pci_ioctl(struct file *file, unsigned int cmd,
|
|
#endif /* HAVE_PCI_MMAP */
|
|
int ret = 0;
|
|
|
|
+ if (!capable(CAP_COMPROMISE_KERNEL))
|
|
+ return -EPERM;
|
|
+
|
|
switch (cmd) {
|
|
case PCIIOC_CONTROLLER:
|
|
ret = pci_domain_nr(dev->bus);
|
|
@@ -259,7 +265,7 @@ static int proc_bus_pci_mmap(struct file *file, struct vm_area_struct *vma)
|
|
struct pci_filp_private *fpriv = file->private_data;
|
|
int i, ret;
|
|
|
|
- if (!capable(CAP_SYS_RAWIO))
|
|
+ if (!capable(CAP_SYS_RAWIO) || !capable(CAP_COMPROMISE_KERNEL))
|
|
return -EPERM;
|
|
|
|
/* Make sure the caller is mapping a real resource for this device */
|
|
diff --git a/drivers/pci/syscall.c b/drivers/pci/syscall.c
|
|
index e1c1ec5..97e785f 100644
|
|
--- a/drivers/pci/syscall.c
|
|
+++ b/drivers/pci/syscall.c
|
|
@@ -92,7 +92,7 @@ SYSCALL_DEFINE5(pciconfig_write, unsigned long, bus, unsigned long, dfn,
|
|
u32 dword;
|
|
int err = 0;
|
|
|
|
- if (!capable(CAP_SYS_ADMIN))
|
|
+ if (!capable(CAP_SYS_ADMIN) || !capable(CAP_COMPROMISE_KERNEL))
|
|
return -EPERM;
|
|
|
|
dev = pci_get_bus_and_slot(bus, dfn);
|
|
--
|
|
1.8.0.2
|
|
|
|
|
|
From b4deb668b754ffa53bc9bebf72bd4679e5f2eb62 Mon Sep 17 00:00:00 2001
|
|
From: Matthew Garrett <mjg@redhat.com>
|
|
Date: Thu, 20 Sep 2012 10:40:58 -0400
|
|
Subject: [PATCH 11/18] x86: Lock down IO port access in secure boot
|
|
environments
|
|
|
|
IO port access would permit users to gain access to PCI configuration
|
|
registers, which in turn (on a lot of hardware) give access to MMIO register
|
|
space. This would potentially permit root to trigger arbitrary DMA, so lock
|
|
it down by default.
|
|
|
|
Signed-off-by: Matthew Garrett <mjg@redhat.com>
|
|
---
|
|
arch/x86/kernel/ioport.c | 4 ++--
|
|
drivers/char/mem.c | 3 +++
|
|
2 files changed, 5 insertions(+), 2 deletions(-)
|
|
|
|
diff --git a/arch/x86/kernel/ioport.c b/arch/x86/kernel/ioport.c
|
|
index 8c96897..a2578c4 100644
|
|
--- a/arch/x86/kernel/ioport.c
|
|
+++ b/arch/x86/kernel/ioport.c
|
|
@@ -28,7 +28,7 @@ asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int turn_on)
|
|
|
|
if ((from + num <= from) || (from + num > IO_BITMAP_BITS))
|
|
return -EINVAL;
|
|
- if (turn_on && !capable(CAP_SYS_RAWIO))
|
|
+ if (turn_on && (!capable(CAP_SYS_RAWIO) || !capable(CAP_COMPROMISE_KERNEL)))
|
|
return -EPERM;
|
|
|
|
/*
|
|
@@ -102,7 +102,7 @@ long sys_iopl(unsigned int level, struct pt_regs *regs)
|
|
return -EINVAL;
|
|
/* Trying to gain more privileges? */
|
|
if (level > old) {
|
|
- if (!capable(CAP_SYS_RAWIO))
|
|
+ if (!capable(CAP_SYS_RAWIO) || !capable(CAP_COMPROMISE_KERNEL))
|
|
return -EPERM;
|
|
}
|
|
regs->flags = (regs->flags & ~X86_EFLAGS_IOPL) | (level << 12);
|
|
diff --git a/drivers/char/mem.c b/drivers/char/mem.c
|
|
index c6fa3bc..fc28099 100644
|
|
--- a/drivers/char/mem.c
|
|
+++ b/drivers/char/mem.c
|
|
@@ -597,6 +597,9 @@ static ssize_t write_port(struct file *file, const char __user *buf,
|
|
unsigned long i = *ppos;
|
|
const char __user * tmp = buf;
|
|
|
|
+ if (!capable(CAP_COMPROMISE_KERNEL))
|
|
+ return -EPERM;
|
|
+
|
|
if (!access_ok(VERIFY_READ, buf, count))
|
|
return -EFAULT;
|
|
while (count-- > 0 && i < 65536) {
|
|
--
|
|
1.8.0.2
|
|
|
|
|
|
From c38e94fdbc44b0e3e8dc2a42db18c04ee25d3627 Mon Sep 17 00:00:00 2001
|
|
From: Matthew Garrett <mjg@redhat.com>
|
|
Date: Thu, 20 Sep 2012 10:40:59 -0400
|
|
Subject: [PATCH 12/18] ACPI: Limit access to custom_method
|
|
|
|
It must be impossible for even root to get code executed in kernel context
|
|
under a secure boot environment. custom_method effectively allows arbitrary
|
|
access to system memory, so it needs to have a capability check here.
|
|
|
|
Signed-off-by: Matthew Garrett <mjg@redhat.com>
|
|
---
|
|
drivers/acpi/custom_method.c | 3 +++
|
|
1 file changed, 3 insertions(+)
|
|
|
|
diff --git a/drivers/acpi/custom_method.c b/drivers/acpi/custom_method.c
|
|
index 5d42c24..247d58b 100644
|
|
--- a/drivers/acpi/custom_method.c
|
|
+++ b/drivers/acpi/custom_method.c
|
|
@@ -29,6 +29,9 @@ static ssize_t cm_write(struct file *file, const char __user * user_buf,
|
|
struct acpi_table_header table;
|
|
acpi_status status;
|
|
|
|
+ if (!capable(CAP_COMPROMISE_KERNEL))
|
|
+ return -EPERM;
|
|
+
|
|
if (!(*ppos)) {
|
|
/* parse the table header to get the table length */
|
|
if (count <= sizeof(struct acpi_table_header))
|
|
--
|
|
1.8.0.2
|
|
|
|
|
|
From b935abbd7888103d6261fa49a797c3f621222593 Mon Sep 17 00:00:00 2001
|
|
From: Matthew Garrett <mjg@redhat.com>
|
|
Date: Thu, 20 Sep 2012 10:41:00 -0400
|
|
Subject: [PATCH 13/18] asus-wmi: Restrict debugfs interface
|
|
|
|
We have no way of validating what all of the Asus WMI methods do on a
|
|
given machine, and there's a risk that some will allow hardware state to
|
|
be manipulated in such a way that arbitrary code can be executed in the
|
|
kernel. Add a capability check to prevent that.
|
|
|
|
Signed-off-by: Matthew Garrett <mjg@redhat.com>
|
|
---
|
|
drivers/platform/x86/asus-wmi.c | 9 +++++++++
|
|
1 file changed, 9 insertions(+)
|
|
|
|
diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
|
|
index f80ae4d..059195f 100644
|
|
--- a/drivers/platform/x86/asus-wmi.c
|
|
+++ b/drivers/platform/x86/asus-wmi.c
|
|
@@ -1521,6 +1521,9 @@ static int show_dsts(struct seq_file *m, void *data)
|
|
int err;
|
|
u32 retval = -1;
|
|
|
|
+ if (!capable(CAP_COMPROMISE_KERNEL))
|
|
+ return -EPERM;
|
|
+
|
|
err = asus_wmi_get_devstate(asus, asus->debug.dev_id, &retval);
|
|
|
|
if (err < 0)
|
|
@@ -1537,6 +1540,9 @@ static int show_devs(struct seq_file *m, void *data)
|
|
int err;
|
|
u32 retval = -1;
|
|
|
|
+ if (!capable(CAP_COMPROMISE_KERNEL))
|
|
+ return -EPERM;
|
|
+
|
|
err = asus_wmi_set_devstate(asus->debug.dev_id, asus->debug.ctrl_param,
|
|
&retval);
|
|
|
|
@@ -1561,6 +1567,9 @@ static int show_call(struct seq_file *m, void *data)
|
|
union acpi_object *obj;
|
|
acpi_status status;
|
|
|
|
+ if (!capable(CAP_COMPROMISE_KERNEL))
|
|
+ return -EPERM;
|
|
+
|
|
status = wmi_evaluate_method(ASUS_WMI_MGMT_GUID,
|
|
1, asus->debug.method_id,
|
|
&input, &output);
|
|
--
|
|
1.8.0.2
|
|
|
|
|
|
From 0e2d67fe7c9f067ebb527ce6a665e89d7a5a398b Mon Sep 17 00:00:00 2001
|
|
From: Matthew Garrett <mjg@redhat.com>
|
|
Date: Thu, 20 Sep 2012 10:41:01 -0400
|
|
Subject: [PATCH 14/18] Restrict /dev/mem and /dev/kmem in secure boot setups
|
|
|
|
Allowing users to write to address space makes it possible for the kernel
|
|
to be subverted. Restrict this when we need to protect the kernel.
|
|
|
|
Signed-off-by: Matthew Garrett <mjg@redhat.com>
|
|
---
|
|
drivers/char/mem.c | 6 ++++++
|
|
1 file changed, 6 insertions(+)
|
|
|
|
diff --git a/drivers/char/mem.c b/drivers/char/mem.c
|
|
index fc28099..b5df7a8 100644
|
|
--- a/drivers/char/mem.c
|
|
+++ b/drivers/char/mem.c
|
|
@@ -158,6 +158,9 @@ static ssize_t write_mem(struct file *file, const char __user *buf,
|
|
unsigned long copied;
|
|
void *ptr;
|
|
|
|
+ if (!capable(CAP_COMPROMISE_KERNEL))
|
|
+ return -EPERM;
|
|
+
|
|
if (!valid_phys_addr_range(p, count))
|
|
return -EFAULT;
|
|
|
|
@@ -530,6 +533,9 @@ static ssize_t write_kmem(struct file *file, const char __user *buf,
|
|
char * kbuf; /* k-addr because vwrite() takes vmlist_lock rwlock */
|
|
int err = 0;
|
|
|
|
+ if (!capable(CAP_COMPROMISE_KERNEL))
|
|
+ return -EPERM;
|
|
+
|
|
if (p < (unsigned long) high_memory) {
|
|
unsigned long to_write = min_t(unsigned long, count,
|
|
(unsigned long)high_memory - p);
|
|
--
|
|
1.8.0.2
|
|
|
|
|
|
From 45f09b7aedcc79d9d315a1c3e926ad36b15edf1a Mon Sep 17 00:00:00 2001
|
|
From: Josh Boyer <jwboyer@redhat.com>
|
|
Date: Thu, 20 Sep 2012 10:41:04 -0400
|
|
Subject: [PATCH 15/18] acpi: Ignore acpi_rsdp kernel parameter in a secure
|
|
boot environment
|
|
|
|
This option allows userspace to pass the RSDP address to the kernel. This
|
|
could potentially be used to circumvent the secure boot trust model.
|
|
We ignore the setting if we don't have the CAP_COMPROMISE_KERNEL capability.
|
|
|
|
Signed-off-by: Josh Boyer <jwboyer@redhat.com>
|
|
---
|
|
drivers/acpi/osl.c | 2 +-
|
|
1 file changed, 1 insertion(+), 1 deletion(-)
|
|
|
|
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
|
|
index 3ff2678..794d78b 100644
|
|
--- a/drivers/acpi/osl.c
|
|
+++ b/drivers/acpi/osl.c
|
|
@@ -246,7 +246,7 @@ early_param("acpi_rsdp", setup_acpi_rsdp);
|
|
acpi_physical_address __init acpi_os_get_root_pointer(void)
|
|
{
|
|
#ifdef CONFIG_KEXEC
|
|
- if (acpi_rsdp)
|
|
+ if (acpi_rsdp && capable(CAP_COMPROMISE_KERNEL))
|
|
return acpi_rsdp;
|
|
#endif
|
|
|
|
--
|
|
1.8.0.2
|
|
|
|
|
|
From 2def5cc3c511d824af306468ff0fd15fa641c412 Mon Sep 17 00:00:00 2001
|
|
From: Matthew Garrett <mjg@redhat.com>
|
|
Date: Tue, 4 Sep 2012 11:55:13 -0400
|
|
Subject: [PATCH 16/18] kexec: Disable in a secure boot environment
|
|
|
|
kexec could be used as a vector for a malicious user to use a signed kernel
|
|
to circumvent the secure boot trust model. In the long run we'll want to
|
|
support signed kexec payloads, but for the moment we should just disable
|
|
loading entirely in that situation.
|
|
|
|
Signed-off-by: Matthew Garrett <mjg@redhat.com>
|
|
---
|
|
kernel/kexec.c | 2 +-
|
|
1 file changed, 1 insertion(+), 1 deletion(-)
|
|
|
|
diff --git a/kernel/kexec.c b/kernel/kexec.c
|
|
index 5e4bd78..dd464e0 100644
|
|
--- a/kernel/kexec.c
|
|
+++ b/kernel/kexec.c
|
|
@@ -943,7 +943,7 @@ SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments,
|
|
int result;
|
|
|
|
/* We only trust the superuser with rebooting the system. */
|
|
- if (!capable(CAP_SYS_BOOT))
|
|
+ if (!capable(CAP_SYS_BOOT) || !capable(CAP_COMPROMISE_KERNEL))
|
|
return -EPERM;
|
|
|
|
/*
|
|
--
|
|
1.8.0.2
|
|
|
|
|
|
From 6af5862bf800c29d9b2c46bee91c463e1c0d77ab Mon Sep 17 00:00:00 2001
|
|
From: Josh Boyer <jwboyer@redhat.com>
|
|
Date: Fri, 5 Oct 2012 10:12:48 -0400
|
|
Subject: [PATCH 17/18] MODSIGN: Always enforce module signing in a Secure Boot
|
|
environment
|
|
|
|
If a machine is booted into a Secure Boot environment, we need to
|
|
protect the trust model. This requires that all modules be signed
|
|
with a key that is in the kernel's _modsign keyring. The checks for
|
|
this are already done via the 'sig_enforce' module parameter. Make
|
|
this visible within the kernel and force it to be true.
|
|
|
|
Signed-off-by: Josh Boyer <jwboyer@redhat.com>
|
|
---
|
|
kernel/cred.c | 8 ++++++++
|
|
kernel/module.c | 4 ++--
|
|
2 files changed, 10 insertions(+), 2 deletions(-)
|
|
|
|
diff --git a/kernel/cred.c b/kernel/cred.c
|
|
index c3f4e3e..c5554e0 100644
|
|
--- a/kernel/cred.c
|
|
+++ b/kernel/cred.c
|
|
@@ -565,11 +565,19 @@ void __init cred_init(void)
|
|
0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
|
|
}
|
|
|
|
+#ifdef CONFIG_MODULE_SIG
|
|
+extern bool sig_enforce;
|
|
+#endif
|
|
+
|
|
void __init secureboot_enable()
|
|
{
|
|
pr_info("Secure boot enabled\n");
|
|
cap_lower((&init_cred)->cap_bset, CAP_COMPROMISE_KERNEL);
|
|
cap_lower((&init_cred)->cap_permitted, CAP_COMPROMISE_KERNEL);
|
|
+#ifdef CONFIG_MODULE_SIG
|
|
+ /* Enable module signature enforcing */
|
|
+ sig_enforce = true;
|
|
+#endif
|
|
}
|
|
|
|
/* Dummy Secure Boot enable option to fake out UEFI SB=1 */
|
|
diff --git a/kernel/module.c b/kernel/module.c
|
|
index 250092c..265172a 100644
|
|
--- a/kernel/module.c
|
|
+++ b/kernel/module.c
|
|
@@ -109,9 +109,9 @@ struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
|
|
|
|
#ifdef CONFIG_MODULE_SIG
|
|
#ifdef CONFIG_MODULE_SIG_FORCE
|
|
-static bool sig_enforce = true;
|
|
+bool sig_enforce = true;
|
|
#else
|
|
-static bool sig_enforce = false;
|
|
+bool sig_enforce = false;
|
|
|
|
static int param_set_bool_enable_only(const char *val,
|
|
const struct kernel_param *kp)
|
|
--
|
|
1.8.0.2
|
|
|
|
|
|
From e45330362517d08579cdaddc718febe68e2cae06 Mon Sep 17 00:00:00 2001
|
|
From: Josh Boyer <jwboyer@redhat.com>
|
|
Date: Fri, 26 Oct 2012 14:02:09 -0400
|
|
Subject: [PATCH 18/18] hibernate: Disable in a Secure Boot environment
|
|
|
|
There is currently no way to verify the resume image when returning
|
|
from hibernate. This might compromise the secure boot trust model,
|
|
so until we can work with signed hibernate images we disable it in
|
|
a Secure Boot environment.
|
|
|
|
Signed-off-by: Josh Boyer <jwboyer@redhat.com>
|
|
---
|
|
kernel/power/hibernate.c | 15 ++++++++++++++-
|
|
kernel/power/main.c | 7 ++++++-
|
|
kernel/power/user.c | 3 +++
|
|
3 files changed, 23 insertions(+), 2 deletions(-)
|
|
|
|
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
|
|
index b26f5f1..26bdfa8 100644
|
|
--- a/kernel/power/hibernate.c
|
|
+++ b/kernel/power/hibernate.c
|
|
@@ -28,6 +28,7 @@
|
|
#include <linux/syscore_ops.h>
|
|
#include <linux/ctype.h>
|
|
#include <linux/genhd.h>
|
|
+#include <linux/efi.h>
|
|
|
|
#include "power.h"
|
|
|
|
@@ -632,6 +633,10 @@ int hibernate(void)
|
|
{
|
|
int error;
|
|
|
|
+ if (!capable(CAP_COMPROMISE_KERNEL)) {
|
|
+ return -EPERM;
|
|
+ }
|
|
+
|
|
lock_system_sleep();
|
|
/* The snapshot device should not be opened while we're running */
|
|
if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
|
|
@@ -723,7 +728,7 @@ static int software_resume(void)
|
|
/*
|
|
* If the user said "noresume".. bail out early.
|
|
*/
|
|
- if (noresume)
|
|
+ if (noresume || !capable(CAP_COMPROMISE_KERNEL))
|
|
return 0;
|
|
|
|
/*
|
|
@@ -889,6 +894,11 @@ static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
|
|
int i;
|
|
char *start = buf;
|
|
|
|
+ if (secure_boot_enabled) {
|
|
+ buf += sprintf(buf, "[%s]\n", "disabled");
|
|
+ return buf-start;
|
|
+ }
|
|
+
|
|
for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
|
|
if (!hibernation_modes[i])
|
|
continue;
|
|
@@ -923,6 +933,9 @@ static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
|
|
char *p;
|
|
int mode = HIBERNATION_INVALID;
|
|
|
|
+ if (!capable(CAP_COMPROMISE_KERNEL))
|
|
+ return -EPERM;
|
|
+
|
|
p = memchr(buf, '\n', n);
|
|
len = p ? p - buf : n;
|
|
|
|
diff --git a/kernel/power/main.c b/kernel/power/main.c
|
|
index 1c16f91..8e3456d 100644
|
|
--- a/kernel/power/main.c
|
|
+++ b/kernel/power/main.c
|
|
@@ -15,6 +15,7 @@
|
|
#include <linux/workqueue.h>
|
|
#include <linux/debugfs.h>
|
|
#include <linux/seq_file.h>
|
|
+#include <linux/efi.h>
|
|
|
|
#include "power.h"
|
|
|
|
@@ -301,7 +302,11 @@ static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
|
|
}
|
|
#endif
|
|
#ifdef CONFIG_HIBERNATION
|
|
- s += sprintf(s, "%s\n", "disk");
|
|
+ if (!secure_boot_enabled) {
|
|
+ s += sprintf(s, "%s\n", "disk");
|
|
+ } else {
|
|
+ s += sprintf(s, "\n");
|
|
+ }
|
|
#else
|
|
if (s != buf)
|
|
/* convert the last space to a newline */
|
|
diff --git a/kernel/power/user.c b/kernel/power/user.c
|
|
index 4ed81e7..b11a0f4 100644
|
|
--- a/kernel/power/user.c
|
|
+++ b/kernel/power/user.c
|
|
@@ -48,6 +48,9 @@ static int snapshot_open(struct inode *inode, struct file *filp)
|
|
struct snapshot_data *data;
|
|
int error;
|
|
|
|
+ if (!capable(CAP_COMPROMISE_KERNEL))
|
|
+ return -EPERM;
|
|
+
|
|
lock_system_sleep();
|
|
|
|
if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
|
|
--
|
|
1.8.0.2
|
|
|