[PATCH v6 3/6] tpm: Support boot measurements

Eddie James eajames at linux.ibm.com
Thu Feb 23 18:52:53 CET 2023


On 2/23/23 03:47, Ilias Apalodimas wrote:
> On Thu, 23 Feb 2023 at 11:30, Ilias Apalodimas
> <ilias.apalodimas at linaro.org> wrote:
>> On Thu, 23 Feb 2023 at 11:02, Ilias Apalodimas
>> <ilias.apalodimas at linaro.org> wrote:
>>> Hi Eddie,
>>>
>>>          final_event->number_of_events++;
>>>> @@ -350,66 +142,6 @@ static efi_status_t tcg2_agile_log_append(u32 pcr_index, u32 event_type,
>>>>        return ret;
>>>>   }
>>>>
>>>> -/**
>>>> - * platform_get_tpm_device() - retrieve TPM device
>>>> - *
>>>> - * This function retrieves the udevice implementing a TPM
>>>> - *
>>>> - * This function may be overridden if special initialization is needed.
>>>> - *
>>>> - * @dev:     udevice
>>>> - * Return:   status code
>>>> - */
>>>> -__weak efi_status_t platform_get_tpm2_device(struct udevice **dev)
>>>> -{
>>>> -     for_each_tpm_device(*dev) {
>>>> -             /* Only support TPMv2 devices */
>>>> -             if (tpm_get_version(*dev) == TPM_V2)
>>>> -                     return EFI_SUCCESS;
>>>> -     }
>>>> -
>>>> -     return EFI_NOT_FOUND;
>>>> -}
>>>> -
>>>> -/**
>>>> - * platform_get_eventlog() - retrieve the eventlog address and size
>>>> - *
>>>> - * This function retrieves the eventlog address and size if the underlying
>>>> - * firmware has done some measurements and passed them.
>>>> - *
>>>> - * This function may be overridden based on platform specific method of
>>>> - * passing the eventlog address and size.
>>>> - *
>>>> - * @dev:     udevice
>>>> - * @addr:    eventlog address
>>>> - * @sz:              eventlog size
>>>> - * Return:   status code
>>>> - */
>>>> -__weak efi_status_t platform_get_eventlog(struct udevice *dev, u64 *addr,
>>>> -                                       u32 *sz)
>>>> -{
>>>> -     const u64 *basep;
>>>> -     const u32 *sizep;
>>>> -
>>>> -     basep = dev_read_prop(dev, "tpm_event_log_addr", NULL);
>>>> -     if (!basep)
>>>> -             return EFI_NOT_FOUND;
>>>> -
>>>> -     *addr = be64_to_cpup((__force __be64 *)basep);
>>>> -
>>>> -     sizep = dev_read_prop(dev, "tpm_event_log_size", NULL);
>>>> -     if (!sizep)
>>>> -             return EFI_NOT_FOUND;
>>>> -
>>>> -     *sz = be32_to_cpup((__force __be32 *)sizep);
>>>> -     if (*sz == 0) {
>>>> -             log_debug("event log empty\n");
>>>> -             return EFI_NOT_FOUND;
>>>> -     }
>>>> -
>>>> -     return EFI_SUCCESS;
>>>> -}
>>>> -
>>>>   /**
>>>>    * tpm2_get_max_command_size() - get the supported max command size
>>>>    *
>>>> @@ -485,239 +217,6 @@ static int tpm2_get_manufacturer_id(struct udevice *dev, u32 *manufacturer_id)
>>>>        return 0;
>>>>   }
>>>>
>>>> -/**
>>>> - * tpm2_get_num_pcr() - get the number of PCRs
>>>> - *
>>>> - * @dev:             TPM device
>>>> - * @manufacturer_id: output buffer for the number
>>>> - *
>>>> - * Return: 0 on success, -1 on error
>>>> - */
>>>> -static int tpm2_get_num_pcr(struct udevice *dev, u32 *num_pcr)
>>>> -{
>>>> -     u8 response[TPM2_RESPONSE_BUFFER_SIZE];
>>>> -     u32 ret;
>>>> -
>>>> -     memset(response, 0, sizeof(response));
>>>> -     ret = tpm2_get_capability(dev, TPM2_CAP_TPM_PROPERTIES,
>>>> -                               TPM2_PT_PCR_COUNT, response, 1);
>>>> -     if (ret)
>>>> -             return -1;
>>>> -
>>>> -     *num_pcr = get_unaligned_be32(response + properties_offset);
>>>> -     if (*num_pcr > TPM2_MAX_PCRS)
>>>> -             return -1;
>>>> -
>>>> -     return 0;
>>>> -}
>>>> -
>>>> -/**
>>>> - * is_active_pcr() - Check if a supported algorithm is active
>>>> - *
>>>> - * @dev:             TPM device
>>>> - * @selection:               struct of PCR information
>>>> - *
>>>> - * Return: true if PCR is active
>>>> - */
>>>> -static bool is_active_pcr(struct tpms_pcr_selection *selection)
>>>> -{
>>>> -     int i;
>>>> -     /*
>>>> -      * check the pcr_select. If at least one of the PCRs supports the
>>>> -      * algorithm add it on the active ones
>>>> -      */
>>>> -     for (i = 0; i < selection->size_of_select; i++) {
>>>> -             if (selection->pcr_select[i])
>>>> -                     return true;
>>>> -     }
>>>> -
>>>> -     return false;
>>>> -}
>>>> -
>>>> -/**
>>>> - * tpm2_get_pcr_info() - get the supported, active PCRs and number of banks
>>>> - *
>>>> - * @dev:             TPM device
>>>> - * @supported_pcr:   bitmask with the algorithms supported
>>>> - * @active_pcr:              bitmask with the active algorithms
>>>> - * @pcr_banks:               number of PCR banks
>>>> - *
>>>> - * Return: 0 on success, -1 on error
>>>> - */
>>>> -static int tpm2_get_pcr_info(struct udevice *dev, u32 *supported_pcr,
>>>> -                          u32 *active_pcr, u32 *pcr_banks)
>>>> -{
>>>> -     u8 response[TPM2_RESPONSE_BUFFER_SIZE];
>>>> -     struct tpml_pcr_selection pcrs;
>>>> -     u32 ret, num_pcr;
>>>> -     size_t i;
>>>> -     int tpm_ret;
>>>> -
>>>> -     *supported_pcr = 0;
>>>> -     *active_pcr = 0;
>>>> -     *pcr_banks = 0;
>>>> -     memset(response, 0, sizeof(response));
>>>> -     ret = tpm2_get_capability(dev, TPM2_CAP_PCRS, 0, response, 1);
>>>> -     if (ret)
>>>> -             goto out;
>>>> -
>>>> -     pcrs.count = get_unaligned_be32(response);
>>>> -     /*
>>>> -      * We only support 5 algorithms for now so check against that
>>>> -      * instead of TPM2_NUM_PCR_BANKS
>>>> -      */
>>>> -     if (pcrs.count > MAX_HASH_COUNT || pcrs.count < 1)
>>>> -             goto out;
>>>> -
>>>> -     tpm_ret = tpm2_get_num_pcr(dev, &num_pcr);
>>>> -     if (tpm_ret)
>>>> -             goto out;
>>>> -
>>>> -     for (i = 0; i < pcrs.count; i++) {
>>>> -             /*
>>>> -              * Definition of TPMS_PCR_SELECTION Structure
>>>> -              * hash: u16
>>>> -              * size_of_select: u8
>>>> -              * pcr_select: u8 array
>>>> -              *
>>>> -              * The offsets depend on the number of the device PCRs
>>>> -              * so we have to calculate them based on that
>>>> -              */
>>>> -             u32 hash_offset = offsetof(struct tpml_pcr_selection, selection) +
>>>> -                     i * offsetof(struct tpms_pcr_selection, pcr_select) +
>>>> -                     i * ((num_pcr + 7) / 8);
>>>> -             u32 size_select_offset =
>>>> -                     hash_offset + offsetof(struct tpms_pcr_selection,
>>>> -                                            size_of_select);
>>>> -             u32 pcr_select_offset =
>>>> -                     hash_offset + offsetof(struct tpms_pcr_selection,
>>>> -                                            pcr_select);
>>>> -
>>>> -             pcrs.selection[i].hash =
>>>> -                     get_unaligned_be16(response + hash_offset);
>>>> -             pcrs.selection[i].size_of_select =
>>>> -                     __get_unaligned_be(response + size_select_offset);
>>>> -             if (pcrs.selection[i].size_of_select > TPM2_PCR_SELECT_MAX)
>>>> -                     goto out;
>>>> -             /* copy the array of pcr_select */
>>>> -             memcpy(pcrs.selection[i].pcr_select, response + pcr_select_offset,
>>>> -                    pcrs.selection[i].size_of_select);
>>>> -     }
>>>> -
>>>> -     for (i = 0; i < pcrs.count; i++) {
>>>> -             u32 hash_mask = alg_to_mask(pcrs.selection[i].hash);
>>>> -
>>>> -             if (hash_mask) {
>>>> -                     *supported_pcr |= hash_mask;
>>>> -                     if (is_active_pcr(&pcrs.selection[i]))
>>>> -                             *active_pcr |= hash_mask;
>>>> -             } else {
>>>> -                     EFI_PRINT("Unknown algorithm %x\n", pcrs.selection[i].hash);
>>>> -             }
>>>> -     }
>>>> -
>>>> -     *pcr_banks = pcrs.count;
>>>> -
>>>> -     return 0;
>>>> -out:
>>>> -     return -1;
>>>> -}
>>>> -
>>>> -/**
>>>> - * __get_active_pcr_banks() - returns the currently active PCR banks
>>>> - *
>>>> - * @active_pcr_banks:                pointer for receiving the bitmap of currently
>>>> - *                           active PCR banks
>>>> - *
>>>> - * Return:   status code
>>>> - */
>>>> -static efi_status_t __get_active_pcr_banks(u32 *active_pcr_banks)
>>>> -{
>>>> -     struct udevice *dev;
>>>> -     u32 active = 0, supported = 0, pcr_banks = 0;
>>>> -     efi_status_t ret;
>>>> -     int err;
>>>> -
>>>> -     ret = platform_get_tpm2_device(&dev);
>>>> -     if (ret != EFI_SUCCESS)
>>>> -             goto out;
>>>> -
>>>> -     err = tpm2_get_pcr_info(dev, &supported, &active, &pcr_banks);
>>>> -     if (err) {
>>>> -             ret = EFI_DEVICE_ERROR;
>>>> -             goto out;
>>>> -     }
>>>> -
>>>> -     *active_pcr_banks = active;
>>>> -
>>>> -out:
>>>> -     return ret;
>>>> -}
>>>> -
>>>> -/* tcg2_create_digest - create a list of digests of the supported PCR banks
>>>> - *                   for a given memory range
>>>> - *
>>>> - * @input:           input memory
>>>> - * @length:          length of buffer to calculate the digest
>>>> - * @digest_list:     list of digests to fill in
>>>> - *
>>>> - * Return:           status code
>>>> - */
>>>> -static efi_status_t tcg2_create_digest(const u8 *input, u32 length,
>>>> -                                    struct tpml_digest_values *digest_list)
>>>> -{
>>>> -     sha1_context ctx;
>>>> -     sha256_context ctx_256;
>>>> -     sha512_context ctx_512;
>>>> -     u8 final[TPM2_SHA512_DIGEST_SIZE];
>>>> -     efi_status_t ret;
>>>> -     u32 active;
>>>> -     size_t i;
>>>> -
>>>> -     ret = __get_active_pcr_banks(&active);
>>>> -     if (ret != EFI_SUCCESS)
>>>> -             return ret;
>>>> -
>>>> -     digest_list->count = 0;
>>>> -     for (i = 0; i < MAX_HASH_COUNT; i++) {
>>>> -             u16 hash_alg = hash_algo_list[i].hash_alg;
>>>> -
>>>> -             if (!(active & alg_to_mask(hash_alg)))
>>>> -                     continue;
>>>> -             switch (hash_alg) {
>>>> -             case TPM2_ALG_SHA1:
>>>> -                     sha1_starts(&ctx);
>>>> -                     sha1_update(&ctx, input, length);
>>>> -                     sha1_finish(&ctx, final);
>>>> -                     break;
>>>> -             case TPM2_ALG_SHA256:
>>>> -                     sha256_starts(&ctx_256);
>>>> -                     sha256_update(&ctx_256, input, length);
>>>> -                     sha256_finish(&ctx_256, final);
>>>> -                     break;
>>>> -             case TPM2_ALG_SHA384:
>>>> -                     sha384_starts(&ctx_512);
>>>> -                     sha384_update(&ctx_512, input, length);
>>>> -                     sha384_finish(&ctx_512, final);
>>>> -                     break;
>>>> -             case TPM2_ALG_SHA512:
>>>> -                     sha512_starts(&ctx_512);
>>>> -                     sha512_update(&ctx_512, input, length);
>>>> -                     sha512_finish(&ctx_512, final);
>>>> -                     break;
>>>> -             default:
>>>> -                     EFI_PRINT("Unsupported algorithm %x\n", hash_alg);
>>>> -                     return EFI_INVALID_PARAMETER;
>>>> -             }
>>>> -             digest_list->digests[digest_list->count].hash_alg = hash_alg;
>>>> -             memcpy(&digest_list->digests[digest_list->count].digest, final,
>>>> -                    (u32)alg_to_len(hash_alg));
>>>> -             digest_list->count++;
>>>> -     }
>>>> -
>>>> -     return EFI_SUCCESS;
>>>> -}
>>>> -
>>>>   /**
>>>>    * efi_tcg2_get_capability() - protocol capability information and state information
>>>>    *
>>>> @@ -759,7 +258,7 @@ efi_tcg2_get_capability(struct efi_tcg2_protocol *this,
>>>>        capability->protocol_version.major = 1;
>>>>        capability->protocol_version.minor = 1;
>>>>
>>>> -     efi_ret = platform_get_tpm2_device(&dev);
>>>> +     efi_ret = tcg2_platform_get_tpm2(&dev);
>>>>        if (efi_ret != EFI_SUCCESS) {
>>>>                capability->supported_event_logs = 0;
>>>>                capability->hash_algorithm_bitmap = 0;
>>>> @@ -855,7 +354,7 @@ efi_tcg2_get_eventlog(struct efi_tcg2_protocol *this,
>>>>                goto out;
>>>>        }
>>>>
>>>> -     ret = platform_get_tpm2_device(&dev);
>>>> +     ret = tcg2_platform_get_tpm2(&dev);
>>>>        if (ret != EFI_SUCCESS) {
>>>>                event_log_location = NULL;
>>>>                event_log_last_entry = NULL;
>>>> @@ -890,6 +389,7 @@ static efi_status_t tcg2_hash_pe_image(void *efi, u64 efi_size,
>>>>        struct efi_image_regions *regs = NULL;
>>>>        void *new_efi = NULL;
>>>>        u8 hash[TPM2_SHA512_DIGEST_SIZE];
>>>> +     struct udevice *dev;
>>>>        efi_status_t ret;
>>>>        u32 active;
>>>>        int i;
>>>> @@ -905,16 +405,20 @@ static efi_status_t tcg2_hash_pe_image(void *efi, u64 efi_size,
>>>>                goto out;
>>>>        }
>>>>
>>>> -     ret = __get_active_pcr_banks(&active);
>>>> +     ret = tcg2_platform_get_tpm2(&dev);
>>>> +     if (ret != EFI_SUCCESS)
>>>> +             goto out;
>>>> +
>>>> +     ret = tcg2_get_active_pcr_banks(dev, &active);
>>>>        if (ret != EFI_SUCCESS) {
>>>>                goto out;
>>>>        }
>>>>
>>>>        digest_list->count = 0;
>>>> -     for (i = 0; i < MAX_HASH_COUNT; i++) {
>>>> -             u16 hash_alg = hash_algo_list[i].hash_alg;
>>>> +     for (i = 0; i < ARRAY_SIZE(tpm2_supported_algorithms); i++) {
>>>> +             u16 hash_alg = tpm2_supported_algorithms[i];
>>>>
>>>> -             if (!(active & alg_to_mask(hash_alg)))
>>>> +             if (!(active & tpm2_algorithm_to_mask(hash_alg)))
>>>>                        continue;
>>>>                switch (hash_alg) {
>>>>                case TPM2_ALG_SHA1:
>>>> @@ -935,7 +439,7 @@ static efi_status_t tcg2_hash_pe_image(void *efi, u64 efi_size,
>>>>                }
>>>>                digest_list->digests[digest_list->count].hash_alg = hash_alg;
>>>>                memcpy(&digest_list->digests[digest_list->count].digest, hash,
>>>> -                    (u32)alg_to_len(hash_alg));
>>>> +                    (u32)tpm2_algorithm_to_len(hash_alg));
>>>>                digest_list->count++;
>>>>        }
>>>>
>>>> @@ -975,7 +479,7 @@ efi_status_t tcg2_measure_pe_image(void *efi, u64 efi_size,
>>>>        if (!is_tcg2_protocol_installed())
>>>>                return EFI_SUCCESS;
>>>>
>>>> -     ret = platform_get_tpm2_device(&dev);
>>>> +     ret = tcg2_platform_get_tpm2(&dev);
>>>>        if (ret != EFI_SUCCESS)
>>>>                return EFI_SECURITY_VIOLATION;
>>>>
>>>> @@ -1084,7 +588,7 @@ efi_tcg2_hash_log_extend_event(struct efi_tcg2_protocol *this, u64 flags,
>>>>                goto out;
>>>>        }
>>>>
>>>> -     ret = platform_get_tpm2_device(&dev);
>>>> +     ret = tcg2_platform_get_tpm2(&dev);
>>>>        if (ret != EFI_SUCCESS)
>>>>                goto out;
>>>>
>>>> @@ -1119,7 +623,7 @@ efi_tcg2_hash_log_extend_event(struct efi_tcg2_protocol *this, u64 flags,
>>>>                ret = tcg2_hash_pe_image((void *)(uintptr_t)data_to_hash,
>>>>                                         data_to_hash_len, &digest_list);
>>>>        } else {
>>>> -             ret = tcg2_create_digest((u8 *)(uintptr_t)data_to_hash,
>>>> +             ret = tcg2_create_digest(dev, (u8 *)(uintptr_t)data_to_hash,
>>>>                                         data_to_hash_len, &digest_list);
>>>>        }
>>>>
>>>> @@ -1182,7 +686,7 @@ efi_tcg2_submit_command(struct efi_tcg2_protocol *this,
>>>>                goto out;
>>>>        }
>>>>
>>>> -     ret = platform_get_tpm2_device(&dev);
>>>> +     ret = tcg2_platform_get_tpm2(&dev);
>>>>        if (ret != EFI_SUCCESS)
>>>>                goto out;
>>>>
>>>> @@ -1211,6 +715,7 @@ static efi_status_t EFIAPI
>>>>   efi_tcg2_get_active_pcr_banks(struct efi_tcg2_protocol *this,
>>>>                              u32 *active_pcr_banks)
>>>>   {
>>>> +     struct udevice *dev;
>>>>        efi_status_t ret;
>>>>
>>>>        if (!this || !active_pcr_banks) {
>>>> @@ -1218,8 +723,12 @@ efi_tcg2_get_active_pcr_banks(struct efi_tcg2_protocol *this,
>>>>                goto out;
>>>>        }
>>>>
>>>> +     ret = tcg2_platform_get_tpm2(&dev);
>>>> +     if (ret != EFI_SUCCESS)
>>>> +             goto out;
>>>> +
>>>>        EFI_ENTRY("%p, %p", this, active_pcr_banks);
>>>> -     ret = __get_active_pcr_banks(active_pcr_banks);
>>>> +     ret = tcg2_get_active_pcr_banks(dev, active_pcr_banks);
>>>>
>>>>   out:
>>>>        return EFI_EXIT(ret);
>>>> @@ -1270,397 +779,6 @@ static const struct efi_tcg2_protocol efi_tcg2_protocol = {
>>>>        .get_result_of_set_active_pcr_banks = efi_tcg2_get_result_of_set_active_pcr_banks,
>>>>   };
>>>>
>>>> -/**
>>>> - * parse_event_log_header() -  Parse and verify the event log header fields
>>>> - *
>>>> - * @buffer:                  Pointer to the start of the eventlog
>>>> - * @size:                    Size of the eventlog
>>>> - * @pos:                     Return offset of the next event in buffer right
>>>> - *                           after the event header i.e specID
>>>> - *
>>>> - * Return:   status code
>>>> - */
>>>> -static efi_status_t parse_event_log_header(void *buffer, u32 size, u32 *pos)
>>>> -{
>>>> -     struct tcg_pcr_event *event_header = (struct tcg_pcr_event *)buffer;
>>>> -     int i = 0;
>>>> -
>>>> -     if (size < sizeof(*event_header))
>>>> -             return EFI_COMPROMISED_DATA;
>>>> -
>>>> -     if (get_unaligned_le32(&event_header->pcr_index) != 0 ||
>>>> -         get_unaligned_le32(&event_header->event_type) != EV_NO_ACTION)
>>>> -             return EFI_COMPROMISED_DATA;
>>>> -
>>>> -     for (i = 0; i < sizeof(event_header->digest); i++) {
>>>> -             if (event_header->digest[i])
>>>> -                     return EFI_COMPROMISED_DATA;
>>>> -     }
>>>> -
>>>> -     *pos += sizeof(*event_header);
>>>> -
>>>> -     return EFI_SUCCESS;
>>>> -}
>>>> -
>>>> -/**
>>>> - * parse_specid_event() -  Parse and verify the specID Event in the eventlog
>>>> - *
>>>> - * @dev:             udevice
>>>> - * @buffer:          Pointer to the start of the eventlog
>>>> - * @log_size:                Size of the eventlog
>>>> - * @pos:             [in] Offset of specID event in the eventlog buffer
>>>> - *                   [out] Return offset of the next event in the buffer
>>>> - *                   after the specID
>>>> - * @digest_list:     list of digests in the event
>>>> - *
>>>> - * Return:           status code
>>>> - * @pos                      Offset in the eventlog where the specID event ends
>>>> - * @digest_list:     list of digests in the event
>>>> - */
>>>> -static efi_status_t parse_specid_event(struct udevice *dev, void *buffer,
>>>> -                                    u32 log_size, u32 *pos,
>>>> -                                    struct tpml_digest_values *digest_list)
>>>> -{
>>>> -     struct tcg_efi_spec_id_event *spec_event;
>>>> -     struct tcg_pcr_event *event_header = (struct tcg_pcr_event *)buffer;
>>>> -     size_t spec_event_size;
>>>> -     u32 active = 0, supported = 0, pcr_count = 0, alg_count = 0;
>>>> -     u32 spec_active = 0;
>>>> -     u16 hash_alg;
>>>> -     u8 vendor_sz;
>>>> -     int err, i;
>>>> -
>>>> -     if (*pos >= log_size || (*pos + sizeof(*spec_event)) > log_size)
>>>> -             return EFI_COMPROMISED_DATA;
>>>> -
>>>> -     /* Check specID event data */
>>>> -     spec_event = (struct tcg_efi_spec_id_event *)((uintptr_t)buffer + *pos);
>>>> -     /* Check for signature */
>>>> -     if (memcmp(spec_event->signature, TCG_EFI_SPEC_ID_EVENT_SIGNATURE_03,
>>>> -                sizeof(TCG_EFI_SPEC_ID_EVENT_SIGNATURE_03))) {
>>>> -             log_err("specID Event: Signature mismatch\n");
>>>> -             return EFI_COMPROMISED_DATA;
>>>> -     }
>>>> -
>>>> -     if (spec_event->spec_version_minor !=
>>>> -                     TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MINOR_TPM2 ||
>>>> -         spec_event->spec_version_major !=
>>>> -                     TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MAJOR_TPM2)
>>>> -             return EFI_COMPROMISED_DATA;
>>>> -
>>>> -     if (spec_event->number_of_algorithms > MAX_HASH_COUNT ||
>>>> -         spec_event->number_of_algorithms < 1) {
>>>> -             log_err("specID Event: Number of algorithms incorrect\n");
>>>> -             return EFI_COMPROMISED_DATA;
>>>> -     }
>>>> -
>>>> -     alg_count = spec_event->number_of_algorithms;
>>>> -
>>>> -     err = tpm2_get_pcr_info(dev, &supported, &active, &pcr_count);
>>>> -     if (err)
>>>> -             return EFI_DEVICE_ERROR;
>>>> -
>>>> -     digest_list->count = 0;
>>>> -     /*
>>>> -      * We have to take care that the sequence of algorithms that we record
>>>> -      * in digest_list matches the sequence in eventlog.
>>>> -      */
>>>> -     for (i = 0; i < alg_count; i++) {
>>>> -             hash_alg =
>>>> -               get_unaligned_le16(&spec_event->digest_sizes[i].algorithm_id);
>>>> -
>>>> -             if (!(supported & alg_to_mask(hash_alg))) {
>>>> -                     log_err("specID Event: Unsupported algorithm\n");
>>>> -                     return EFI_COMPROMISED_DATA;
>>>> -             }
>>>> -             digest_list->digests[digest_list->count++].hash_alg = hash_alg;
>>>> -
>>>> -             spec_active |= alg_to_mask(hash_alg);
>>>> -     }
>>>> -
>>>> -     /*
>>>> -      * TCG specification expects the event log to have hashes for all
>>>> -      * active PCR's
>>>> -      */
>>>> -     if (spec_active != active) {
>>>> -             /*
>>>> -              * Previous stage bootloader should know all the active PCR's
>>>> -              * and use them in the Eventlog.
>>>> -              */
>>>> -             log_err("specID Event: All active hash alg not present\n");
>>>> -             return EFI_COMPROMISED_DATA;
>>>> -     }
>>>> -
>>>> -     /*
>>>> -      * the size of the spec event and placement of vendor_info_size
>>>> -      * depends on supported algoriths
>>>> -      */
>>>> -     spec_event_size =
>>>> -             offsetof(struct tcg_efi_spec_id_event, digest_sizes) +
>>>> -             alg_count * sizeof(spec_event->digest_sizes[0]);
>>>> -
>>>> -     if (*pos + spec_event_size >= log_size)
>>>> -             return EFI_COMPROMISED_DATA;
>>>> -
>>>> -     vendor_sz = *(uint8_t *)((uintptr_t)buffer + *pos + spec_event_size);
>>>> -
>>>> -     spec_event_size += sizeof(vendor_sz) + vendor_sz;
>>>> -     *pos += spec_event_size;
>>>> -
>>>> -     if (get_unaligned_le32(&event_header->event_size) != spec_event_size) {
>>>> -             log_err("specID event: header event size mismatch\n");
>>>> -             /* Right way to handle this can be to call SetActive PCR's */
>>>> -             return EFI_COMPROMISED_DATA;
>>>> -     }
>>>> -
>>>> -     return EFI_SUCCESS;
>>>> -}
>>>> -
>>>> -/**
>>>> - * tcg2_parse_event() -  Parse the event in the eventlog
>>>> - *
>>>> - * @dev:             udevice
>>>> - * @buffer:          Pointer to the start of the eventlog
>>>> - * @log_size:                Size of the eventlog
>>>> - * @offset:          [in] Offset of the event in the eventlog buffer
>>>> - *                   [out] Return offset of the next event in the buffer
>>>> - * @digest_list:     list of digests in the event
>>>> - * @pcr                      Index of the PCR in the event
>>>> - *
>>>> - * Return:           status code
>>>> - */
>>>> -static efi_status_t tcg2_parse_event(struct udevice *dev, void *buffer,
>>>> -                                  u32 log_size, u32 *offset,
>>>> -                                  struct tpml_digest_values *digest_list,
>>>> -                                  u32 *pcr)
>>>> -{
>>>> -     struct tcg_pcr_event2 *event = NULL;
>>>> -     u32 count, size, event_size;
>>>> -     size_t pos;
>>>> -
>>>> -     event_size = tcg_event_final_size(digest_list);
>>>> -     if (*offset >= log_size || *offset + event_size > log_size) {
>>>> -             log_err("Event exceeds log size\n");
>>>> -             return EFI_COMPROMISED_DATA;
>>>> -     }
>>>> -
>>>> -     event = (struct tcg_pcr_event2 *)((uintptr_t)buffer + *offset);
>>>> -     *pcr = get_unaligned_le32(&event->pcr_index);
>>>> -
>>>> -     /* get the count */
>>>> -     count = get_unaligned_le32(&event->digests.count);
>>>> -     if (count != digest_list->count)
>>>> -             return EFI_COMPROMISED_DATA;
>>>> -
>>>> -     pos = offsetof(struct tcg_pcr_event2, digests);
>>>> -     pos += offsetof(struct tpml_digest_values, digests);
>>>> -
>>>> -     for (int i = 0; i < digest_list->count; i++) {
>>>> -             u16 alg;
>>>> -             u16 hash_alg = digest_list->digests[i].hash_alg;
>>>> -             u8 *digest = (u8 *)&digest_list->digests[i].digest;
>>>> -
>>>> -             alg = get_unaligned_le16((void *)((uintptr_t)event + pos));
>>>> -
>>>> -             if (alg != hash_alg)
>>>> -                     return EFI_COMPROMISED_DATA;
>>>> -
>>>> -             pos += offsetof(struct tpmt_ha, digest);
>>>> -             memcpy(digest, (void *)((uintptr_t)event + pos), alg_to_len(hash_alg));
>>>> -             pos += alg_to_len(hash_alg);
>>>> -     }
>>>> -
>>>> -     size = get_unaligned_le32((void *)((uintptr_t)event + pos));
>>>> -     event_size += size;
>>>> -     pos += sizeof(u32); /* tcg_pcr_event2 event_size*/
>>>> -     pos += size;
>>>> -
>>>> -     /* make sure the calculated buffer is what we checked against */
>>>> -     if (pos != event_size)
>>>> -             return EFI_COMPROMISED_DATA;
>>>> -
>>>> -     if (pos > log_size)
>>>> -             return EFI_COMPROMISED_DATA;
>>>> -
>>>> -     *offset += pos;
>>>> -
>>>> -     return EFI_SUCCESS;
>>>> -}
>>>> -
>>>> -/**
>>>> - * tcg2_get_fw_eventlog() -  Get the eventlog address and size
>>>> - *
>>>> - * If the previous firmware has passed some eventlog, this function get it's
>>>> - * location and check for it's validity.
>>>> - *
>>>> - * @dev:             udevice
>>>> - * @log_buffer:              eventlog address
>>>> - * @log_sz:          eventlog size
>>>> - *
>>>> - * Return:   status code
>>>> - */
>>>> -static efi_status_t tcg2_get_fw_eventlog(struct udevice *dev, void *log_buffer,
>>>> -                                      size_t *log_sz)
>>>> -{
>>>> -     struct tpml_digest_values digest_list;
>>>> -     void *buffer;
>>>> -     efi_status_t ret;
>>>> -     u32 pcr, pos;
>>>> -     u64 base;
>>>> -     u32 sz;
>>>> -     bool extend_pcr = false;
>>>> -     int i;
>>>> -
>>>> -     ret = platform_get_eventlog(dev, &base, &sz);
>>>> -     if (ret != EFI_SUCCESS)
>>>> -             return ret;
>>>> -
>>>> -     if (sz > TPM2_EVENT_LOG_SIZE)
>>>> -             return EFI_VOLUME_FULL;
>>>> -
>>>> -     buffer = (void *)(uintptr_t)base;
>>>> -     pos = 0;
>>>> -     /* Parse the eventlog to check for its validity */
>>>> -     ret = parse_event_log_header(buffer, sz, &pos);
>>>> -     if (ret)
>>>> -             return ret;
>>>> -
>>>> -     ret = parse_specid_event(dev, buffer, sz, &pos, &digest_list);
>>>> -     if (ret) {
>>>> -             log_err("Error parsing SPEC ID Event\n");
>>>> -             return ret;
>>>> -     }
>>>> -
>>>> -     ret = tcg2_pcr_read(dev, 0, &digest_list);
>>>> -     if (ret) {
>>>> -             log_err("Error reading PCR 0\n");
>>>> -             return ret;
>>>> -     }
>>>> -
>>>> -     /*
>>>> -      * If PCR0 is 0, previous firmware didn't have the capability
>>>> -      * to extend the PCR. In this scenario, extend the PCR as
>>>> -      * the eventlog is parsed.
>>>> -      */
>>>> -     for (i = 0; i < digest_list.count; i++) {
>>>> -             u8 hash_buf[TPM2_SHA512_DIGEST_SIZE] = { 0 };
>>>> -             u16 hash_alg = digest_list.digests[i].hash_alg;
>>>> -
>>>> -             if (!memcmp((u8 *)&digest_list.digests[i].digest, hash_buf,
>>>> -                         alg_to_len(hash_alg)))
>>>> -                     extend_pcr = true;
>>>> -     }
>>>> -
>>>> -     while (pos < sz) {
>>>> -             ret = tcg2_parse_event(dev, buffer, sz, &pos, &digest_list,
>>>> -                                    &pcr);
>>>> -             if (ret) {
>>>> -                     log_err("Error parsing event\n");
>>>> -                     return ret;
>>>> -             }
>>>> -             if (extend_pcr) {
>>>> -                     ret = tcg2_pcr_extend(dev, pcr, &digest_list);
>>>> -                     if (ret != EFI_SUCCESS) {
>>>> -                             log_err("Error in extending PCR\n");
>>>> -                             return ret;
>>>> -                     }
>>>> -
>>>> -                     /* Clear the digest for next event */
>>>> -                     for (i = 0; i < digest_list.count; i++) {
>>>> -                             u16 hash_alg = digest_list.digests[i].hash_alg;
>>>> -                             u8 *digest =
>>>> -                                (u8 *)&digest_list.digests[i].digest;
>>>> -
>>>> -                             memset(digest, 0, alg_to_len(hash_alg));
>>>> -                     }
>>>> -             }
>>>> -     }
>>>> -
>>>> -     memcpy(log_buffer, buffer, sz);
>>>> -     *log_sz = sz;
>>>> -
>>>> -     return ret;
>>>> -}
>>>> -
>>>> -/**
>>>> - * create_specid_event() - Create the first event in the eventlog
>>>> - *
>>>> - * @dev:                     tpm device
>>>> - * @event_header:            Pointer to the final event header
>>>> - * @event_size:                      final spec event size
>>>> - *
>>>> - * Return:   status code
>>>> - */
>>>> -static efi_status_t create_specid_event(struct udevice *dev, void *buffer,
>>>> -                                     size_t *event_size)
>>>> -{
>>>> -     struct tcg_efi_spec_id_event *spec_event;
>>>> -     size_t spec_event_size;
>>>> -     efi_status_t ret = EFI_DEVICE_ERROR;
>>>> -     u32 active = 0, supported = 0, pcr_count = 0, alg_count = 0;
>>>> -     int err;
>>>> -     size_t i;
>>>> -
>>>> -     /*
>>>> -      * Create Spec event. This needs to be the first event in the log
>>>> -      * according to the TCG EFI protocol spec
>>>> -      */
>>>> -
>>>> -     /* Setup specID event data */
>>>> -     spec_event = (struct tcg_efi_spec_id_event *)buffer;
>>>> -     memcpy(spec_event->signature, TCG_EFI_SPEC_ID_EVENT_SIGNATURE_03,
>>>> -            sizeof(spec_event->signature));
>>>> -     put_unaligned_le32(0, &spec_event->platform_class); /* type client */
>>>> -     spec_event->spec_version_minor =
>>>> -             TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MINOR_TPM2;
>>>> -     spec_event->spec_version_major =
>>>> -             TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MAJOR_TPM2;
>>>> -     spec_event->spec_errata =
>>>> -             TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_ERRATA_TPM2;
>>>> -     spec_event->uintn_size = sizeof(efi_uintn_t) / sizeof(u32);
>>>> -
>>>> -     err = tpm2_get_pcr_info(dev, &supported, &active, &pcr_count);
>>>> -
>>>> -     if (err)
>>>> -             goto out;
>>>> -
>>>> -     for (i = 0; i < pcr_count; i++) {
>>>> -             u16 hash_alg = hash_algo_list[i].hash_alg;
>>>> -             u16 hash_len = hash_algo_list[i].hash_len;
>>>> -
>>>> -             if (active & alg_to_mask(hash_alg)) {
>>>> -                     put_unaligned_le16(hash_alg,
>>>> -                                        &spec_event->digest_sizes[alg_count].algorithm_id);
>>>> -                     put_unaligned_le16(hash_len,
>>>> -                                        &spec_event->digest_sizes[alg_count].digest_size);
>>>> -                     alg_count++;
>>>> -             }
>>>> -     }
>>>> -
>>>> -     spec_event->number_of_algorithms = alg_count;
>>>> -     if (spec_event->number_of_algorithms > MAX_HASH_COUNT ||
>>>> -         spec_event->number_of_algorithms < 1)
>>>> -             goto out;
>>>> -
>>>> -     /*
>>>> -      * the size of the spec event and placement of vendor_info_size
>>>> -      * depends on supported algoriths
>>>> -      */
>>>> -     spec_event_size =
>>>> -             offsetof(struct tcg_efi_spec_id_event, digest_sizes) +
>>>> -             spec_event->number_of_algorithms * sizeof(spec_event->digest_sizes[0]);
>>>> -     /* no vendor info for us */
>>>> -     memset(buffer + spec_event_size, 0, 1);
>>>> -     /* add a byte for vendor_info_size in the spec event */
>>>> -     spec_event_size += 1;
>>>> -     *event_size = spec_event_size;
>>>> -
>>>> -     return EFI_SUCCESS;
>>>> -
>>>> -out:
>>>> -     return ret;
>>>> -}
>>>> -
>>>>   /**
>>>>    * tcg2_uninit - remove the final event table and free efi memory on failures
>>>>    */
>>>> @@ -1722,7 +840,7 @@ out:
>>>>   }
>>>>
>>>>   /**
>>>> - * tcg2_measure_event() - common function to add event log and extend PCR
>>>> + * measure_event() - common function to add event log and extend PCR
>>>>    *
>>>>    * @dev:             TPM device
>>>>    * @pcr_index:               PCR index
>>>> @@ -1732,14 +850,13 @@ out:
>>>>    *
>>>>    * Return:   status code
>>>>    */
>>>> -static efi_status_t
>>>> -tcg2_measure_event(struct udevice *dev, u32 pcr_index, u32 event_type,
>>>> -                u32 size, u8 event[])
>>>> +static efi_status_t measure_event(struct udevice *dev, u32 pcr_index,
>>>> +                               u32 event_type, u32 size, u8 event[])
>>>>   {
>>>>        struct tpml_digest_values digest_list;
>>>>        efi_status_t ret;
>>>>
>>>> -     ret = tcg2_create_digest(event, size, &digest_list);
>>>> +     ret = tcg2_create_digest(dev, event, size, &digest_list);
>>>>        if (ret != EFI_SUCCESS)
>>>>                goto out;
>>>>
>>>> @@ -1766,9 +883,8 @@ static efi_status_t efi_append_scrtm_version(struct udevice *dev)
>>>>   {
>>>>        efi_status_t ret;
>>>>
>>>> -     ret = tcg2_measure_event(dev, 0, EV_S_CRTM_VERSION,
>>>> -                              strlen(version_string) + 1,
>>>> -                              (u8 *)version_string);
>>>> +     ret = measure_event(dev, 0, EV_S_CRTM_VERSION,
>>>> +                         strlen(version_string) + 1, (u8 *)version_string);
>>>>
>>>>        return ret;
>>>>   }
>>>> @@ -1784,12 +900,11 @@ static efi_status_t efi_init_event_log(void)
>>>>         * vendor_info_size is currently set to 0, we need to change the length
>>>>         * and allocate the flexible array member if this changes
>>>>         */
>>>> -     struct tcg_pcr_event *event_header = NULL;
>>>> +     struct tcg2_event_log elog;
>>>>        struct udevice *dev;
>>>> -     size_t spec_event_size;
>>>>        efi_status_t ret;
>>>>
>>>> -     ret = platform_get_tpm2_device(&dev);
>>>> +     ret = tcg2_platform_get_tpm2(&dev);
>>>>        if (ret != EFI_SUCCESS)
>>>>                return ret;
>>>>
>>>> @@ -1808,7 +923,6 @@ static efi_status_t efi_init_event_log(void)
>>>>         * The log header is defined to be in SHA1 event log entry format.
>>>>         * Setup event header
>>>>         */
>>>> -     event_header =  (struct tcg_pcr_event *)event_log.buffer;
>>>>        event_log.pos = 0;
>>>>        event_log.last_event_size = 0;
>>>>        event_log.get_event_called = false;
>>>> @@ -1819,34 +933,19 @@ static efi_status_t efi_init_event_log(void)
>>>>         * Check if earlier firmware have passed any eventlog. Different
>>>>         * platforms can use different ways to do so.
>>>>         */
>>>> -     ret = tcg2_get_fw_eventlog(dev, event_log.buffer, &event_log.pos);
>>>> +     ret = tcg2_init_log(dev, &elog);
>>>> +     if (ret != EFI_SUCCESS)
>>>> +             goto free_pool;
>>> So I think this is the last bit we need to change in order to support EFI
>>> properly.  I read the email regarding the newly added reserved memory memory
>>> to the TPM node and it's fine, but that won't work for the existing U-Boot
>>> dtbs.  Since this was working out of the box, I'd still prefer to keep that
>>> working even if that entry is missing.
>>>
>>> If you look at this function, there is an efi_allocate_pool() call a few
>>> lines above.  What this does is allocate the EventLog memory for EFI.
>>> Note here that this *has* to be EFI memory since the kernel's efi-stub
>>> can still call into the firmware (and in fact it does, that's who we measure
>>> the initrd in > 5.18 kernels).  After the allocation it looks for those DT
>>> entries, and if tpm_event_log_addr is found it parses the EventLog and
>>> 1. Extends the PCRs
>>> 2. Adds the events into the Eventlog
>>>
>>> The reason for that is that TF-A (the Arm first stage boot loader),
>>> doesn't have any TPM drivers.  So U-Boot is trying to be 'smart' here.
>>> We are grabbing the EventLog from the previous bootloader and if PCR0!=0 we
>>> replay that into the hardware and re-create the EventLog.
>>>
>>> [...]
>>
>> This  will fix the protocol installation, however there's still still
>> something missing on the EFI side, since reading the eventlog fails
>> with
>>
>> tpm2_eventlog /sys/kernel/security/tpm0/binary_bios_measurements
>> version: 1
>> events:
>> ERROR: failed to parse tpm2 eventlog
>> ERROR: Unable to run tpm2_eventlog
>> But at least the kernel can find the EFI config tables properly.
>> Also, note that the ret is efi_status_t and the new function you added
>> returns an int.  Just switch the ret here accordingly.
>>
>>
>>           * platforms can use different ways to do so.
>>           */
>>          ret = tcg2_init_log(dev, &elog);
>> -       if (ret != EFI_SUCCESS)
>> -               goto free_pool;
>> -
>> -       memcpy(event_log.buffer, elog.log, elog.log_position);
>> -       event_log.pos = elog.log_position;
>> +       if (ret == EFI_SUCCESS) {
>> +               memcpy(event_log.buffer, elog.log, elog.log_position);
>> +               event_log.pos = elog.log_position;
>> +       }
>>
>>
>> I'll try digging into the EFI issues more once I get some time
> Ok Ignore the previous mail. I just noticed that the specid event is
> generated by tcg2_log_init() and that's where the errors come from.


OK, I think I understand the problem. One problem with your solution 
below is that it's only useful for EFI; writing the event log to a 
temporary buffer in the non-EFI case is a waste of time, since it can't 
go anywhere. I have a solution where the user can pass in their buffer 
in the tcg2_event_log structure in the event that no memory region is 
discovered. EFI can use that path.


Thanks for the debugging effort!

Eddie


>
> So something like the *really ugly hack* fixes EFI.  Can you please
> turn it into human-readable code
>
>   #include <linux/unaligned/be_byteshift.h>
>   #include <linux/unaligned/generic.h>
>   #include <linux/unaligned/le_byteshift.h>
> +#include <malloc.h>
>
>   #include "tpm-utils.h"
>
> @@ -634,7 +635,7 @@ __weak int tcg2_platform_get_log(struct udevice
> *dev, void **addr, u32 *size)
>
>                  if (dev_read_phandle_with_args(dev, "memory-region", NULL, 0,
>                                                 0, &args))
> -                       return -ENODEV;
> +                       goto alloc;
>
>                  a = ofnode_get_addr_size(args.node, "reg", &s);
>                  if (a == FDT_ADDR_T_NONE)
> @@ -643,6 +644,9 @@ __weak int tcg2_platform_get_log(struct udevice
> *dev, void **addr, u32 *size)
>                  *addr = map_physmem(a, s, MAP_NOCACHE);
>                  *size = (u32)s;
>          }
> +alloc:
> +       *addr = calloc(1, 4096);
> +       *size = 4096;
>
>          return 0;
>   }
>
> Cheers
> /Ilias
>
>> Cheers
>> /Ilias
>>> Thanks!
>>> /Ilias


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