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-rw-r--r--src/security/intel/txt/getsec.c25
-rw-r--r--src/security/intel/txt/romstage.c17
2 files changed, 31 insertions, 11 deletions
diff --git a/src/security/intel/txt/getsec.c b/src/security/intel/txt/getsec.c
index af9b7bb471..cd2292745f 100644
--- a/src/security/intel/txt/getsec.c
+++ b/src/security/intel/txt/getsec.c
@@ -9,6 +9,7 @@
#include <cpu/x86/mp.h>
#include <cpu/x86/msr.h>
#include <types.h>
+#include <rules.h>
#include "txt_register.h"
#include "txt_getsec.h"
@@ -24,16 +25,26 @@ static bool getsec_enabled(void)
/*
* Check if SMX and VMX is supported by CPU.
*/
- if (!(ecx & CPUID_SMX) || !(ecx & CPUID_VMX))
+ if (!(ecx & CPUID_SMX) || !(ecx & CPUID_VMX)) {
+ printk(BIOS_ERR, "SMX/VMX not supported by CPU\n");
return false;
-
+ }
/*
- * Check if SMX, VMX and GetSec instructions haven't been disabled.
+ * This requirement is not needed for ENTERACCS, but for SENTER (see SDM).
+ * Skip check in romstage because IA32_FEATURE_CONTROL cannot be unlocked
+ * even after a global reset e.g. on Sandy/IvyBridge. However the register
+ * gets set properly in ramstage where all CPUs are already initialized.
*/
- msr_t msr = rdmsr(IA32_FEATURE_CONTROL);
- if ((msr.lo & 0xff06) != 0xff06)
- return false;
-
+ if (!ENV_ROMSTAGE_OR_BEFORE) {
+ /*
+ * Check if SMX, VMX and GetSec instructions haven't been disabled.
+ */
+ msr_t msr = rdmsr(IA32_FEATURE_CONTROL);
+ if ((msr.lo & 0xff06) != 0xff06) {
+ printk(BIOS_ERR, "GETSEC not enabled in IA32_FEATURE_CONTROL MSR\n");
+ return false;
+ }
+ }
/*
* Enable SMX. Required to execute GetSec instruction.
* Chapter 2.2.4.3
diff --git a/src/security/intel/txt/romstage.c b/src/security/intel/txt/romstage.c
index 63db10f8c3..98308b7ba1 100644
--- a/src/security/intel/txt/romstage.c
+++ b/src/security/intel/txt/romstage.c
@@ -5,6 +5,7 @@
#include <cf9_reset.h>
#include <console/console.h>
#include <cpu/intel/common/common.h>
+#include <cpu/x86/cr.h>
#include <cpu/x86/msr.h>
#include <southbridge/intel/common/pmbase.h>
#include <timer.h>
@@ -83,14 +84,22 @@ static void print_memory_is_locked(void)
void intel_txt_romstage_init(void)
{
/* Bail early if the CPU doesn't support TXT */
- if (!is_txt_cpu())
+ if (!is_txt_cpu()) {
+ printk(BIOS_ERR, "TEE-TXT: CPU not TXT capable.\n");
return;
+ }
- /* We need to use GETSEC here, so enable it */
- enable_getsec_or_reset();
+ /*
+ * We need to use GETSEC here, so enable it.
+ * CR4_SMXE is all we need to be able to call GETSEC[CAPABILITIES]
+ * or GETSEC[ENTERACCS] for SCLEAN.
+ */
+ write_cr4(read_cr4() | CR4_SMXE);
- if (!is_txt_chipset())
+ if (!is_txt_chipset()) {
+ printk(BIOS_ERR, "TEE-TXT: Chipset not TXT capable.\n");
return;
+ }
const uint8_t txt_ests = read8((void *)TXT_ESTS);