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authorTom Rini <trini@konsulko.com>2020-07-16 16:35:15 -0400
committerTom Rini <trini@konsulko.com>2020-07-16 16:35:15 -0400
commitfee68b98fe3890631a9bdf8f8db328179011ee3f (patch)
tree362a05bc5b23abe6183cfc153988351e329fb6da /lib/efi_loader/efi_variable.c
parent3b33eff3f263e6ccadf505e67d450970cc1c8e6c (diff)
parentc70f44817d466848c421ed7159bc9aba428e69ad (diff)
Merge tag 'efi-2020-10-rc1-4' of https://gitlab.denx.de/u-boot/custodians/u-boot-efi
Pull request for UEFI sub-system for efi-2020-10-rc1 (4) Improvements for the UEFI subsystem include: * support for read-only TEE-backed variables * allow to compile PK, KEK, db, dbx fixed values into U-Boot * bug fixes Python testing related changes comprise: * enable 'bootefi hello' for better test coverage * remove SKIP messages in UEFI Python tests The fitupd command is dropped. Build errors for the lsblk command are fixed.
Diffstat (limited to 'lib/efi_loader/efi_variable.c')
-rw-r--r--lib/efi_loader/efi_variable.c203
1 files changed, 30 insertions, 173 deletions
diff --git a/lib/efi_loader/efi_variable.c b/lib/efi_loader/efi_variable.c
index eab5f005da..39a8482903 100644
--- a/lib/efi_loader/efi_variable.c
+++ b/lib/efi_loader/efi_variable.c
@@ -5,12 +5,15 @@
* Copyright (c) 2017 Rob Clark
*/
+#define LOG_CATEGORY LOGC_EFI
+
#include <common.h>
#include <efi_loader.h>
#include <efi_variable.h>
#include <env.h>
#include <env_internal.h>
#include <hexdump.h>
+#include <log.h>
#include <malloc.h>
#include <rtc.h>
#include <search.h>
@@ -18,166 +21,7 @@
#include <crypto/pkcs7_parser.h>
#include <linux/compat.h>
#include <u-boot/crc.h>
-
-enum efi_secure_mode {
- EFI_MODE_SETUP,
- EFI_MODE_USER,
- EFI_MODE_AUDIT,
- EFI_MODE_DEPLOYED,
-};
-
-static bool efi_secure_boot;
-static enum efi_secure_mode efi_secure_mode;
-static u8 efi_vendor_keys;
-
-/**
- * efi_set_secure_state - modify secure boot state variables
- * @secure_boot: value of SecureBoot
- * @setup_mode: value of SetupMode
- * @audit_mode: value of AuditMode
- * @deployed_mode: value of DeployedMode
- *
- * Modify secure boot status related variables as indicated.
- *
- * Return: status code
- */
-static efi_status_t efi_set_secure_state(u8 secure_boot, u8 setup_mode,
- u8 audit_mode, u8 deployed_mode)
-{
- efi_status_t ret;
- const u32 attributes_ro = EFI_VARIABLE_BOOTSERVICE_ACCESS |
- EFI_VARIABLE_RUNTIME_ACCESS |
- EFI_VARIABLE_READ_ONLY;
- const u32 attributes_rw = EFI_VARIABLE_BOOTSERVICE_ACCESS |
- EFI_VARIABLE_RUNTIME_ACCESS;
-
- efi_secure_boot = secure_boot;
-
- ret = efi_set_variable_int(L"SecureBoot", &efi_global_variable_guid,
- attributes_ro, sizeof(secure_boot),
- &secure_boot, false);
- if (ret != EFI_SUCCESS)
- goto err;
-
- ret = efi_set_variable_int(L"SetupMode", &efi_global_variable_guid,
- attributes_ro, sizeof(setup_mode),
- &setup_mode, false);
- if (ret != EFI_SUCCESS)
- goto err;
-
- ret = efi_set_variable_int(L"AuditMode", &efi_global_variable_guid,
- audit_mode || setup_mode ?
- attributes_ro : attributes_rw,
- sizeof(audit_mode), &audit_mode, false);
- if (ret != EFI_SUCCESS)
- goto err;
-
- ret = efi_set_variable_int(L"DeployedMode",
- &efi_global_variable_guid,
- audit_mode || deployed_mode || setup_mode ?
- attributes_ro : attributes_rw,
- sizeof(deployed_mode), &deployed_mode,
- false);
-err:
- return ret;
-}
-
-/**
- * efi_transfer_secure_state - handle a secure boot state transition
- * @mode: new state
- *
- * Depending on @mode, secure boot related variables are updated.
- * Those variables are *read-only* for users, efi_set_variable_int()
- * is called here.
- *
- * Return: status code
- */
-static efi_status_t efi_transfer_secure_state(enum efi_secure_mode mode)
-{
- efi_status_t ret;
-
- EFI_PRINT("Switching secure state from %d to %d\n", efi_secure_mode,
- mode);
-
- if (mode == EFI_MODE_DEPLOYED) {
- ret = efi_set_secure_state(1, 0, 0, 1);
- if (ret != EFI_SUCCESS)
- goto err;
- } else if (mode == EFI_MODE_AUDIT) {
- ret = efi_set_variable_int(L"PK", &efi_global_variable_guid,
- EFI_VARIABLE_BOOTSERVICE_ACCESS |
- EFI_VARIABLE_RUNTIME_ACCESS,
- 0, NULL, false);
- if (ret != EFI_SUCCESS)
- goto err;
-
- ret = efi_set_secure_state(0, 1, 1, 0);
- if (ret != EFI_SUCCESS)
- goto err;
- } else if (mode == EFI_MODE_USER) {
- ret = efi_set_secure_state(1, 0, 0, 0);
- if (ret != EFI_SUCCESS)
- goto err;
- } else if (mode == EFI_MODE_SETUP) {
- ret = efi_set_secure_state(0, 1, 0, 0);
- if (ret != EFI_SUCCESS)
- goto err;
- } else {
- return EFI_INVALID_PARAMETER;
- }
-
- efi_secure_mode = mode;
-
- return EFI_SUCCESS;
-
-err:
- /* TODO: What action should be taken here? */
- printf("ERROR: Secure state transition failed\n");
- return ret;
-}
-
-/**
- * efi_init_secure_state - initialize secure boot state
- *
- * Return: status code
- */
-static efi_status_t efi_init_secure_state(void)
-{
- enum efi_secure_mode mode = EFI_MODE_SETUP;
- efi_uintn_t size = 0;
- efi_status_t ret;
-
- ret = efi_get_variable_int(L"PK", &efi_global_variable_guid,
- NULL, &size, NULL, NULL);
- if (ret == EFI_BUFFER_TOO_SMALL) {
- if (IS_ENABLED(CONFIG_EFI_SECURE_BOOT))
- mode = EFI_MODE_USER;
- }
-
- ret = efi_transfer_secure_state(mode);
- if (ret != EFI_SUCCESS)
- return ret;
-
- /* As we do not provide vendor keys this variable is always 0. */
- ret = efi_set_variable_int(L"VendorKeys",
- &efi_global_variable_guid,
- EFI_VARIABLE_BOOTSERVICE_ACCESS |
- EFI_VARIABLE_RUNTIME_ACCESS |
- EFI_VARIABLE_READ_ONLY,
- sizeof(efi_vendor_keys),
- &efi_vendor_keys, false);
- return ret;
-}
-
-/**
- * efi_secure_boot_enabled - return if secure boot is enabled or not
- *
- * Return: true if enabled, false if disabled
- */
-bool efi_secure_boot_enabled(void)
-{
- return efi_secure_boot;
-}
+#include <asm/sections.h>
#ifdef CONFIG_EFI_SECURE_BOOT
static u8 pkcs7_hdr[] = {
@@ -292,6 +136,7 @@ static efi_status_t efi_variable_authenticate(u16 *variable,
struct efi_time timestamp;
struct rtc_time tm;
u64 new_time;
+ enum efi_auth_var_type var_type;
efi_status_t ret;
var_sig = NULL;
@@ -368,18 +213,20 @@ static efi_status_t efi_variable_authenticate(u16 *variable,
}
/* signature database used for authentication */
- if (u16_strcmp(variable, L"PK") == 0 ||
- u16_strcmp(variable, L"KEK") == 0) {
+ var_type = efi_auth_var_get_type(variable, vendor);
+ switch (var_type) {
+ case EFI_AUTH_VAR_PK:
+ case EFI_AUTH_VAR_KEK:
/* with PK */
truststore = efi_sigstore_parse_sigdb(L"PK");
if (!truststore)
goto err;
- } else if (u16_strcmp(variable, L"db") == 0 ||
- u16_strcmp(variable, L"dbx") == 0) {
+ break;
+ case EFI_AUTH_VAR_DB:
+ case EFI_AUTH_VAR_DBX:
/* with PK and KEK */
truststore = efi_sigstore_parse_sigdb(L"KEK");
truststore2 = efi_sigstore_parse_sigdb(L"PK");
-
if (!truststore) {
if (!truststore2)
goto err;
@@ -387,7 +234,8 @@ static efi_status_t efi_variable_authenticate(u16 *variable,
truststore = truststore2;
truststore2 = NULL;
}
- } else {
+ break;
+ default:
/* TODO: support private authenticated variables */
goto err;
}
@@ -506,6 +354,7 @@ efi_status_t efi_set_variable_int(u16 *variable_name, const efi_guid_t *vendor,
efi_uintn_t ret;
bool append, delete;
u64 time = 0;
+ enum efi_auth_var_type var_type;
if (!variable_name || !*variable_name || !vendor ||
((attributes & EFI_VARIABLE_RUNTIME_ACCESS) &&
@@ -519,10 +368,16 @@ efi_status_t efi_set_variable_int(u16 *variable_name, const efi_guid_t *vendor,
delete = !append && (!data_size || !attributes);
/* check attributes */
+ var_type = efi_auth_var_get_type(variable_name, vendor);
if (var) {
if (ro_check && (var->attr & EFI_VARIABLE_READ_ONLY))
return EFI_WRITE_PROTECTED;
+ if (IS_ENABLED(CONFIG_EFI_VARIABLES_PRESEED)) {
+ if (var_type != EFI_AUTH_VAR_NONE)
+ return EFI_WRITE_PROTECTED;
+ }
+
/* attributes won't be changed */
if (!delete &&
((ro_check && var->attr != attributes) ||
@@ -540,12 +395,7 @@ efi_status_t efi_set_variable_int(u16 *variable_name, const efi_guid_t *vendor,
return EFI_NOT_FOUND;
}
- if (((!u16_strcmp(variable_name, L"PK") ||
- !u16_strcmp(variable_name, L"KEK")) &&
- !guidcmp(vendor, &efi_global_variable_guid)) ||
- ((!u16_strcmp(variable_name, L"db") ||
- !u16_strcmp(variable_name, L"dbx")) &&
- !guidcmp(vendor, &efi_guid_image_security_database))) {
+ if (var_type != EFI_AUTH_VAR_NONE) {
/* authentication is mandatory */
if (!(attributes &
EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS)) {
@@ -604,7 +454,7 @@ efi_status_t efi_set_variable_int(u16 *variable_name, const efi_guid_t *vendor,
if (ret != EFI_SUCCESS)
return ret;
- if (!u16_strcmp(variable_name, L"PK"))
+ if (var_type == EFI_AUTH_VAR_PK)
ret = efi_init_secure_state();
else
ret = EFI_SUCCESS;
@@ -747,5 +597,12 @@ efi_status_t efi_init_variables(void)
if (ret != EFI_SUCCESS)
return ret;
+ if (IS_ENABLED(CONFIG_EFI_VARIABLES_PRESEED)) {
+ ret = efi_var_restore((struct efi_var_file *)
+ __efi_var_file_begin);
+ if (ret != EFI_SUCCESS)
+ log_err("Invalid EFI variable seed\n");
+ }
+
return efi_var_from_file();
}