efi: call get_event_log before ExitBootServices

With TPM 2.0 specification, the event logs may only be accessible by
calling an EFI Boot Service. Modify the EFI stub to copy the log area to
a new Linux-specific EFI configuration table so it remains accessible
once booted.

When calling this service, it is possible to specify the expected format
of the logs: TPM 1.2 (SHA1) or TPM 2.0 ("Crypto Agile"). For now, only the
first format is retrieved.

Signed-off-by: Thiebaud Weksteen <tweek@google.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>

1 files changed, 46 insertions, 0 deletions

diff --git a/include/linux/efi.h b/include/linux/efi.h
index d813f7b04da7..dcea82dc4b89 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -473,6 +473,39 @@ typedef struct {
         u64 get_all;
 } apple_properties_protocol_64_t;
 
+typedef struct {
+        u32 get_capability;
+        u32 get_event_log;
+        u32 hash_log_extend_event;
+        u32 submit_command;
+        u32 get_active_pcr_banks;
+        u32 set_active_pcr_banks;
+        u32 get_result_of_set_active_pcr_banks;
+} efi_tcg2_protocol_32_t;
+
+typedef struct {
+        u64 get_capability;
+        u64 get_event_log;
+        u64 hash_log_extend_event;
+        u64 submit_command;
+        u64 get_active_pcr_banks;
+        u64 set_active_pcr_banks;
+        u64 get_result_of_set_active_pcr_banks;
+} efi_tcg2_protocol_64_t;
+
+typedef u32 efi_tcg2_event_log_format;
+
+typedef struct {
+        void *get_capability;
+        efi_status_t (*get_event_log)(efi_handle_t, efi_tcg2_event_log_format,
+                efi_physical_addr_t *, efi_physical_addr_t *, efi_bool_t *);
+        void *hash_log_extend_event;
+        void *submit_command;
+        void *get_active_pcr_banks;
+        void *set_active_pcr_banks;
+        void *get_result_of_set_active_pcr_banks;
+} efi_tcg2_protocol_t;
+
 /*
  * Types and defines for EFI ResetSystem
  */
@@ -623,6 +656,7 @@ void efi_native_runtime_setup(void);
 #define EFI_MEMORY_ATTRIBUTES_TABLE_GUID        EFI_GUID(0xdcfa911d, 0x26eb, 0x469f,  0xa2, 0x20, 0x38, 0xb7, 0xdc, 0x46, 0x12, 0x20)
 #define EFI_CONSOLE_OUT_DEVICE_GUID             EFI_GUID(0xd3b36f2c, 0xd551, 0x11d4,  0x9a, 0x46, 0x00, 0x90, 0x27, 0x3f, 0xc1, 0x4d)
 #define APPLE_PROPERTIES_PROTOCOL_GUID          EFI_GUID(0x91bd12fe, 0xf6c3, 0x44fb,  0xa5, 0xb7, 0x51, 0x22, 0xab, 0x30, 0x3a, 0xe0)
+#define EFI_TCG2_PROTOCOL_GUID                  EFI_GUID(0x607f766c, 0x7455, 0x42be,  0x93, 0x0b, 0xe4, 0xd7, 0x6d, 0xb2, 0x72, 0x0f)
 
 #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)
@@ -635,6 +669,7 @@ void efi_native_runtime_setup(void);
 #define LINUX_EFI_ARM_SCREEN_INFO_TABLE_GUID    EFI_GUID(0xe03fc20a, 0x85dc, 0x406e,  0xb9, 0x0e, 0x4a, 0xb5, 0x02, 0x37, 0x1d, 0x95)
 #define LINUX_EFI_LOADER_ENTRY_GUID             EFI_GUID(0x4a67b082, 0x0a4c, 0x41cf,  0xb6, 0xc7, 0x44, 0x0b, 0x29, 0xbb, 0x8c, 0x4f)
 #define LINUX_EFI_RANDOM_SEED_TABLE_GUID        EFI_GUID(0x1ce1e5bc, 0x7ceb, 0x42f2,  0x81, 0xe5, 0x8a, 0xad, 0xf1, 0x80, 0xf5, 0x7b)
+#define LINUX_EFI_TPM_EVENT_LOG_GUID            EFI_GUID(0xb7799cb0, 0xeca2, 0x4943,  0x96, 0x67, 0x1f, 0xae, 0x07, 0xb7, 0x47, 0xfa)
 
 typedef struct {
         efi_guid_t guid;
@@ -909,6 +944,7 @@ extern struct efi {
         unsigned long properties_table; /* properties table */
         unsigned long mem_attr_table;   /* memory attributes table */
         unsigned long rng_seed;         /* UEFI firmware random seed */
+        unsigned long tpm_log;          /* TPM2 Event Log table */
         efi_get_time_t *get_time;
         efi_set_time_t *set_time;
         efi_get_wakeup_time_t *get_wakeup_time;
@@ -1534,6 +1570,8 @@ static inline void
 efi_enable_reset_attack_mitigation(efi_system_table_t *sys_table_arg) { }
 #endif
 
+void efi_retrieve_tpm2_eventlog(efi_system_table_t *sys_table);
+
 /*
  * Arch code can implement the following three template macros, avoiding
  * reptition for the void/non-void return cases of {__,}efi_call_virt():
@@ -1601,4 +1639,12 @@ struct linux_efi_random_seed {
         u8      bits[];
 };
 
+struct linux_efi_tpm_eventlog {
+        u32     size;
+        u8      version;
+        u8      log[];
+};
+
+extern int efi_tpm_eventlog_init(void);
+
 #endif /* _LINUX_EFI_H */