(cc Ilias) On Sat, 3 Feb 2024 at 08:58, Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> wrote: > > If the virtual firmware implements TPM support, TCG2 protocol will be > used for kernel measurements and event logging support. But in CC > environment, not all platforms support or enable the TPM feature. UEFI > specification [1] exposes protocol and interfaces used for kernel > measurements in CC platforms without TPM support. > > Currently, the efi-stub only supports the kernel related measurements > for the platform that supports TCG2 protocol. So, extend it add > CC measurement protocol (EFI_CC_MEASUREMENT_PROTOCOL) and event logging > support. Event logging format in the CC environment is the same as > TCG2. > > More details about the EFI CC measurements and logging can be found > in [1]. > > Link: https://uefi.org/specs/UEFI/2.10/38_Confidential_Computing.html#efi-cc-measurement-protocol [1] > Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> > --- > .../firmware/efi/libstub/efi-stub-helper.c | 113 +++++++++++++----- > drivers/firmware/efi/libstub/efistub.h | 73 +++++++++++ > include/linux/efi.h | 1 + > 3 files changed, 159 insertions(+), 28 deletions(-) > > diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c > index bfa30625f5d0..e323b768048f 100644 > --- a/drivers/firmware/efi/libstub/efi-stub-helper.c > +++ b/drivers/firmware/efi/libstub/efi-stub-helper.c > @@ -219,50 +219,107 @@ static const struct { > }, > }; > > +static efi_status_t tcg2_efi_measure(efi_tcg2_protocol_t *tcg2, > + unsigned long load_addr, > + unsigned long load_size, > + enum efistub_event event) > +{ > + struct efi_measured_event { > + efi_tcg2_event_t event_data; > + efi_tcg2_tagged_event_t tagged_event; > + u8 tagged_event_data[]; > + } *evt; > + int size = sizeof(*evt) + events[event].event_data_len; > + efi_status_t status; > + > + status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size, > + (void **)&evt); > + if (status != EFI_SUCCESS) > + return status; > + > + evt->event_data = (struct efi_tcg2_event){ > + .event_size = size, > + .event_header.header_size = sizeof(evt->event_data.event_header), > + .event_header.header_version = EFI_TCG2_EVENT_HEADER_VERSION, > + .event_header.pcr_index = events[event].pcr_index, > + .event_header.event_type = EV_EVENT_TAG, > + }; > + > + evt->tagged_event = (struct efi_tcg2_tagged_event){ > + .tagged_event_id = events[event].event_id, > + .tagged_event_data_size = events[event].event_data_len, > + }; > + > + memcpy(evt->tagged_event_data, events[event].event_data, > + events[event].event_data_len); > + > + status = efi_call_proto(tcg2, hash_log_extend_event, 0, > + load_addr, load_size, &evt->event_data); > + efi_bs_call(free_pool, evt); > + > + return status; > +} > + > +static efi_status_t cc_efi_measure(efi_cc_protocol_t *cc, > + unsigned long load_addr, > + unsigned long load_size, > + enum efistub_event event) > +{ > + efi_cc_mr_index_t mr; > + efi_cc_event_t *evt; > + efi_status_t status; > + size_t size; > + > + status = efi_call_proto(cc, map_pcr_to_mr_index, events[event].pcr_index, &mr); > + if (status != EFI_SUCCESS) { > + efi_err("CC_MEASURE: PCR to MR mapping failed\n"); > + return status; > + } > + > + size = sizeof(*evt) + events[event].event_data_len; > + status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size, (void **)&evt); > + if (status != EFI_SUCCESS) { > + efi_err("CC_MEASURE: Allocating event struct failed\n"); > + return status; > + } > + > + evt->event_size = size; > + evt->event_header.header_size = sizeof(evt->event_header); > + evt->event_header.header_version = EFI_CC_EVENT_HEADER_VERSION; > + evt->event_header.mr_index = mr; > + evt->event_header.event_type = EV_EVENT_TAG; > + memcpy(evt->event_data, events[event].event_data, events[event].event_data_len); > + Why does this look entirely different from the TCG2 version? What happened to the tagged event? > + status = efi_call_proto(cc, hash_log_extend_event, 0, load_addr, load_size, evt); > + efi_bs_call(free_pool, evt); > + > + return status; > +} > static efi_status_t efi_measure_tagged_event(unsigned long load_addr, > unsigned long load_size, > enum efistub_event event) > { > efi_guid_t tcg2_guid = EFI_TCG2_PROTOCOL_GUID; > + efi_guid_t cc_guid = EFI_CC_MEASUREMENT_PROTOCOL_GUID; > + efi_cc_protocol_t *cc = NULL; > efi_tcg2_protocol_t *tcg2 = NULL; > efi_status_t status; > > efi_bs_call(locate_protocol, &tcg2_guid, NULL, (void **)&tcg2); > if (tcg2) { > - struct efi_measured_event { > - efi_tcg2_event_t event_data; > - efi_tcg2_tagged_event_t tagged_event; > - u8 tagged_event_data[]; > - } *evt; > - int size = sizeof(*evt) + events[event].event_data_len; > - > - status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size, > - (void **)&evt); > + status = tcg2_efi_measure(tcg2, load_addr, load_size, event); > if (status != EFI_SUCCESS) > goto fail; > > - evt->event_data = (struct efi_tcg2_event){ > - .event_size = size, > - .event_header.header_size = sizeof(evt->event_data.event_header), > - .event_header.header_version = EFI_TCG2_EVENT_HEADER_VERSION, > - .event_header.pcr_index = events[event].pcr_index, > - .event_header.event_type = EV_EVENT_TAG, > - }; > - > - evt->tagged_event = (struct efi_tcg2_tagged_event){ > - .tagged_event_id = events[event].event_id, > - .tagged_event_data_size = events[event].event_data_len, > - }; > - > - memcpy(evt->tagged_event_data, events[event].event_data, > - events[event].event_data_len); > - > - status = efi_call_proto(tcg2, hash_log_extend_event, 0, > - load_addr, load_size, &evt->event_data); > - efi_bs_call(free_pool, evt); > + return EFI_SUCCESS; > + } > > + efi_bs_call(locate_protocol, &cc_guid, NULL, (void **)&cc); > + if (cc) { > + status = cc_efi_measure(cc, load_addr, load_size, event); > if (status != EFI_SUCCESS) > goto fail; > + > return EFI_SUCCESS; > } > > diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h > index 212687c30d79..dbdeb2ad7a93 100644 > --- a/drivers/firmware/efi/libstub/efistub.h > +++ b/drivers/firmware/efi/libstub/efistub.h > @@ -882,6 +882,79 @@ union efi_tcg2_protocol { > } mixed_mode; > }; > > +typedef struct { > + u8 major; > + u8 minor; > +} efi_cc_version_t; > + > +typedef struct { > + u8 type; > + u8 sub_type; > +} efi_cc_type_t; > + > +/* EFI CC type/subtype defines */ > +#define EFI_CC_TYPE_NONE 0 > +#define EFI_CC_TYPE_AMD_SEV 1 > +#define EFI_CC_TYPE_INTEL_TDX 2 > + > +typedef u32 efi_cc_mr_index_t; > + > +typedef struct { > + u32 event_size; > + struct { > + u32 header_size; > + u16 header_version; > + u32 mr_index; > + u32 event_type; > + } __packed event_header; > + u8 event_data[0]; > +} __packed efi_cc_event_t; > + > +typedef u32 efi_cc_event_log_bitmap_t; > +typedef u32 efi_cc_event_log_format_t; > +typedef u32 efi_cc_event_algorithm_bitmap_t; > + > +typedef struct { > + u8 size; > + efi_cc_version_t structure_version; > + efi_cc_version_t protocol_version; > + efi_cc_event_algorithm_bitmap_t hash_algorithm_bitmap; > + efi_cc_event_log_bitmap_t supported_event_logs; > + efi_cc_type_t cc_type; > +} efi_cc_boot_service_cap_t; > + > +#define EFI_CC_EVENT_HEADER_VERSION 1 > + > +#define EFI_CC_BOOT_HASH_ALG_SHA384 0x00000004 > + > +typedef union efi_cc_protocol efi_cc_protocol_t; > + > +union efi_cc_protocol { > + struct { > + efi_status_t (__efiapi *get_capability)(efi_cc_protocol_t *, > + efi_cc_boot_service_cap_t *); > + efi_status_t (__efiapi *get_event_log)(efi_cc_protocol_t *, > + efi_cc_event_log_format_t, > + efi_physical_addr_t *, > + efi_physical_addr_t *, > + efi_bool_t *); > + efi_status_t (__efiapi *hash_log_extend_event)(efi_cc_protocol_t *, > + u64, > + efi_physical_addr_t, > + u64, > + const efi_cc_event_t *); > + efi_status_t (__efiapi *map_pcr_to_mr_index)(efi_cc_protocol_t *, > + u32, > + efi_cc_mr_index_t *); > + }; > + struct { > + u32 get_capability; > + u32 get_event_log; > + u32 hash_log_extend_event; > + u32 map_pcr_to_mr_index; > + } mixed_mode; > +}; > + > struct riscv_efi_boot_protocol { > u64 revision; > > diff --git a/include/linux/efi.h b/include/linux/efi.h > index c74f47711f0b..2f57fec2e629 100644 > --- a/include/linux/efi.h > +++ b/include/linux/efi.h > @@ -400,6 +400,7 @@ void efi_native_runtime_setup(void); > #define EFI_CERT_X509_GUID EFI_GUID(0xa5c059a1, 0x94e4, 0x4aa7, 0x87, 0xb5, 0xab, 0x15, 0x5c, 0x2b, 0xf0, 0x72) > #define EFI_CERT_X509_SHA256_GUID EFI_GUID(0x3bd2a492, 0x96c0, 0x4079, 0xb4, 0x20, 0xfc, 0xf9, 0x8e, 0xf1, 0x03, 0xed) > #define EFI_CC_BLOB_GUID EFI_GUID(0x067b1f5f, 0xcf26, 0x44c5, 0x85, 0x54, 0x93, 0xd7, 0x77, 0x91, 0x2d, 0x42) > +#define EFI_CC_MEASUREMENT_PROTOCOL_GUID EFI_GUID(0x96751a3d, 0x72f4, 0x41a6, 0xa7, 0x94, 0xed, 0x5d, 0x0e, 0x67, 0xae, 0x6b) > > /* > * This GUID is used to pass to the kernel proper the struct screen_info > -- > 2.25.1 >
