From: Sean Christopherson <sean.j.christopher...@intel.com>

Add X86_FEATURE_SGX_LC, which informs whether or not the CPU supports SGX
Launch Control.

Add MSR_IA32_SGXLEPUBKEYHASH{0, 1, 2, 3}, which when combined contain a
SHA256 hash of a 3072-bit RSA public key. SGX backed software packages, so
called enclaves, are always signed. All enclaves signed with the public key
are unconditionally allowed to initialize. [1]

Add FEAT_CTL_SGX_LC_ENABLED, which informs whether the aformentioned MSRs
are writable or not. If the bit is off, the public key MSRs are read-only
for the OS.

If the MSRs are read-only, the platform must provide a launch enclave (LE).
LE can create cryptographic tokens for other enclaves that they can pass
together with their signature to the ENCLS(EINIT) opcode, which is used
to initialize enclaves.

Linux is unlikely to support the locked configuration because it takes away
the control of the launch decisions from the kernel.

[1] Intel SDM: 38.1.4 Intel SGX Launch Control Configuration

Reviewed-by: Borislav Petkov <b...@alien8.de>
Acked-by: Jethro Beekman <jet...@fortanix.com>
Reviewed-by: Darren Kenny <darren.ke...@oracle.com>
Signed-off-by: Sean Christopherson <sean.j.christopher...@intel.com>
Co-developed-by: Jarkko Sakkinen <jarkko.sakki...@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakki...@linux.intel.com>
---
 arch/x86/include/asm/cpufeatures.h | 1 +
 arch/x86/include/asm/msr-index.h   | 7 +++++++
 2 files changed, 8 insertions(+)

diff --git a/arch/x86/include/asm/cpufeatures.h 
b/arch/x86/include/asm/cpufeatures.h
index 7150001d5232..62b58cda034a 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -357,6 +357,7 @@
 #define X86_FEATURE_MOVDIRI            (16*32+27) /* MOVDIRI instruction */
 #define X86_FEATURE_MOVDIR64B          (16*32+28) /* MOVDIR64B instruction */
 #define X86_FEATURE_ENQCMD             (16*32+29) /* ENQCMD and ENQCMDS 
instructions */
+#define X86_FEATURE_SGX_LC             (16*32+30) /* Software Guard Extensions 
Launch Control */
 
 /* AMD-defined CPU features, CPUID level 0x80000007 (EBX), word 17 */
 #define X86_FEATURE_OVERFLOW_RECOV     (17*32+ 0) /* MCA overflow recovery 
support */
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index 258d555d22f2..d0c6cfff5b55 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -609,6 +609,7 @@
 #define FEAT_CTL_LOCKED                                BIT(0)
 #define FEAT_CTL_VMX_ENABLED_INSIDE_SMX                BIT(1)
 #define FEAT_CTL_VMX_ENABLED_OUTSIDE_SMX       BIT(2)
+#define FEAT_CTL_SGX_LC_ENABLED                        BIT(17)
 #define FEAT_CTL_SGX_ENABLED                   BIT(18)
 #define FEAT_CTL_LMCE_ENABLED                  BIT(20)
 
@@ -629,6 +630,12 @@
 #define MSR_IA32_UCODE_WRITE           0x00000079
 #define MSR_IA32_UCODE_REV             0x0000008b
 
+/* Intel SGX Launch Enclave Public Key Hash MSRs */
+#define MSR_IA32_SGXLEPUBKEYHASH0      0x0000008C
+#define MSR_IA32_SGXLEPUBKEYHASH1      0x0000008D
+#define MSR_IA32_SGXLEPUBKEYHASH2      0x0000008E
+#define MSR_IA32_SGXLEPUBKEYHASH3      0x0000008F
+
 #define MSR_IA32_SMM_MONITOR_CTL       0x0000009b
 #define MSR_IA32_SMBASE                        0x0000009e
 
-- 
2.25.1

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