Hi Kuppuswamy, On Thu, 15 Feb 2024 at 05:02, 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> > --- > > Changes since v1: > * Fixed missing tagged event data. > > .../firmware/efi/libstub/efi-stub-helper.c | 127 ++++++++++++++---- > drivers/firmware/efi/libstub/efistub.h | 74 ++++++++++ > include/linux/efi.h | 1 + > 3 files changed, 174 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..cc31f8143190 100644 > --- a/drivers/firmware/efi/libstub/efi-stub-helper.c > +++ b/drivers/firmware/efi/libstub/efi-stub-helper.c > @@ -219,50 +219,121 @@ 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; This is defined as size_t on the cc variant. I guess both are ok, just pick one > + efi_status_t status; > + > + status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size, > + (void **)&evt); > + if (status != EFI_SUCCESS) pr_err() here as done in the cc variant? > + 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); The struct filling/memcpying looks similar across the 2 functions. I wonder if it makes sense to have a common function for that, with an argument for the event data type. > + 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) > +{ > + struct efi_measured_event { > + efi_cc_event_t event_data; > + efi_tcg2_tagged_event_t tagged_event; > + u8 tagged_event_data[]; > + } *evt; > + size_t size = sizeof(*evt) + events[event].event_data_len; > + efi_cc_mr_index_t mr; > + efi_status_t status; > + > + 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; > + } > + > + 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_data = (struct efi_cc_event){ > + .event_size = size, > + .event_header.header_size = sizeof(evt->event_data.event_header), > + .event_header.header_version = EFI_CC_EVENT_HEADER_VERSION, > + .event_header.mr_index = mr, > + .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(cc, hash_log_extend_event, 0, > + load_addr, load_size, &evt->event_data); > + > + 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; > } > [...] Thanks /Ilias
