diff --git a/src/shared/tpm2-util.c b/src/shared/tpm2-util.c index 9cab153e45..64dcc5503b 100644 --- a/src/shared/tpm2-util.c +++ b/src/shared/tpm2-util.c @@ -65,6 +65,7 @@ static TSS2_RC (*sym_Esys_TR_Close)(ESYS_CONTEXT *esys_context, ESYS_TR *rsrc_ha static TSS2_RC (*sym_Esys_TR_Deserialize)(ESYS_CONTEXT *esys_context, uint8_t const *buffer, size_t buffer_size, ESYS_TR *esys_handle) = NULL; static TSS2_RC (*sym_Esys_TR_FromTPMPublic)(ESYS_CONTEXT *esysContext, TPM2_HANDLE tpm_handle, ESYS_TR optionalSession1, ESYS_TR optionalSession2, ESYS_TR optionalSession3, ESYS_TR *object) = NULL; static TSS2_RC (*sym_Esys_TR_GetName)(ESYS_CONTEXT *esysContext, ESYS_TR handle, TPM2B_NAME **name) = NULL; +static TSS2_RC (*sym_Esys_TR_GetTpmHandle)(ESYS_CONTEXT *esys_context, ESYS_TR esys_handle, TPM2_HANDLE *tpm_handle) = NULL; static TSS2_RC (*sym_Esys_TR_Serialize)(ESYS_CONTEXT *esys_context, ESYS_TR object, uint8_t **buffer, size_t *buffer_size) = NULL; static TSS2_RC (*sym_Esys_TR_SetAuth)(ESYS_CONTEXT *esysContext, ESYS_TR handle, TPM2B_AUTH const *authValue) = NULL; static TSS2_RC (*sym_Esys_TRSess_GetAttributes)(ESYS_CONTEXT *esysContext, ESYS_TR session, TPMA_SESSION *flags) = NULL; @@ -123,6 +124,12 @@ int dlopen_tpm2(void) { if (r < 0) return r; + /* Esys_TR_GetTpmHandle was added to tpm2-tss in version 2.4.0. Once we can set a minimum tpm2-tss + * version of 2.4.0 this sym can be moved up to the normal list above. */ + r = dlsym_many_or_warn(libtss2_esys_dl, LOG_DEBUG, DLSYM_ARG_FORCE(Esys_TR_GetTpmHandle)); + if (r < 0) + log_debug("libtss2-esys too old, does not include Esys_TR_GetTpmHandle."); + r = dlopen_many_sym_or_warn( &libtss2_rc_dl, "libtss2-rc.so.0", LOG_DEBUG, DLSYM_ARG(Tss2_RC_Decode)); @@ -706,53 +713,59 @@ int tpm2_handle_new(Tpm2Context *context, Tpm2Handle **ret_handle) { return 0; } -/* Create a Tpm2Handle object that references a pre-existing handle in the TPM, at the TPM2_HANDLE address - * provided. This should be used only for persistent, transient, or NV handles. Returns 1 on success, 0 if - * the requested handle is not present in the TPM, or < 0 on error. */ -static int tpm2_esys_handle_from_tpm_handle( +/* Create a Tpm2Handle object that references a pre-existing handle in the TPM, at the handle index provided. + * This should be used only for persistent, transient, or NV handles; and the handle must already exist in + * the TPM at the specified handle index. The handle index should not be 0. Returns 1 if found, 0 if the + * index is empty, or < 0 on error. Also see tpm2_get_srk() below; the SRK is a commonly used persistent + * Tpm2Handle. */ +int tpm2_index_to_handle( Tpm2Context *c, + TPM2_HANDLE index, const Tpm2Handle *session, - TPM2_HANDLE tpm_handle, + TPM2B_PUBLIC **ret_public, + TPM2B_NAME **ret_name, + TPM2B_NAME **ret_qname, Tpm2Handle **ret_handle) { TSS2_RC rc; int r; assert(c); - assert(tpm_handle > 0); - assert(ret_handle); /* Let's restrict this, at least for now, to allow only some handle types. */ - switch (TPM2_HANDLE_TYPE(tpm_handle)) { + switch (TPM2_HANDLE_TYPE(index)) { case TPM2_HT_PERSISTENT: case TPM2_HT_NV_INDEX: case TPM2_HT_TRANSIENT: break; case TPM2_HT_PCR: return log_error_errno(SYNTHETIC_ERRNO(EINVAL), - "Refusing to create ESYS handle for PCR handle 0x%08" PRIx32 ".", - tpm_handle); + "Invalid handle 0x%08" PRIx32 " (in PCR range).", index); case TPM2_HT_HMAC_SESSION: case TPM2_HT_POLICY_SESSION: return log_error_errno(SYNTHETIC_ERRNO(EINVAL), - "Refusing to create ESYS handle for session handle 0x%08" PRIx32 ".", - tpm_handle); + "Invalid handle 0x%08" PRIx32 " (in session range).", index); case TPM2_HT_PERMANENT: /* Permanent handles are defined, e.g. ESYS_TR_RH_OWNER. */ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), - "Refusing to create ESYS handle for permanent handle 0x%08" PRIx32 ".", - tpm_handle); + "Invalid handle 0x%08" PRIx32 " (in permanent range).", index); default: return log_error_errno(SYNTHETIC_ERRNO(EINVAL), - "Refusing to create ESYS handle for unknown handle 0x%08" PRIx32 ".", - tpm_handle); + "Invalid handle 0x%08" PRIx32 " (in unknown range).", index); } - r = tpm2_get_capability_handle(c, tpm_handle); + r = tpm2_get_capability_handle(c, index); if (r < 0) return r; if (r == 0) { - log_debug("TPM handle 0x%08" PRIx32 " not populated.", tpm_handle); - *ret_handle = NULL; + log_debug("TPM handle 0x%08" PRIx32 " not populated.", index); + if (ret_public) + *ret_public = NULL; + if (ret_name) + *ret_name = NULL; + if (ret_qname) + *ret_qname = NULL; + if (ret_handle) + *ret_handle = NULL; return 0; } @@ -767,7 +780,7 @@ static int tpm2_esys_handle_from_tpm_handle( rc = sym_Esys_TR_FromTPMPublic( c->esys_context, - tpm_handle, + index, session ? session->esys_handle : ESYS_TR_NONE, ESYS_TR_NONE, ESYS_TR_NONE, @@ -776,25 +789,61 @@ static int tpm2_esys_handle_from_tpm_handle( return log_error_errno(SYNTHETIC_ERRNO(ENOTRECOVERABLE), "Failed to read public info: %s", sym_Tss2_RC_Decode(rc)); - *ret_handle = TAKE_PTR(handle); + if (ret_public || ret_name || ret_qname) { + r = tpm2_read_public(c, session, handle, ret_public, ret_name, ret_qname); + if (r < 0) + return r; + } + + if (ret_handle) + *ret_handle = TAKE_PTR(handle); return 1; } -/* Copy an object in the TPM at a transient location to a persistent location. +/* Get the handle index for the provided Tpm2Handle. */ +int tpm2_index_from_handle(Tpm2Context *c, const Tpm2Handle *handle, TPM2_HANDLE *ret_index) { + TSS2_RC rc; + + assert(c); + assert(handle); + assert(ret_index); + + /* Esys_TR_GetTpmHandle was added to tpm2-tss in version 2.4.0. Once we can set a minimum tpm2-tss + * version of 2.4.0 this check can be removed. */ + if (!sym_Esys_TR_GetTpmHandle) + return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP), + "libtss2-esys too old, does not include Esys_TR_GetTpmHandle."); + + rc = sym_Esys_TR_GetTpmHandle(c->esys_context, handle->esys_handle, ret_index); + if (rc != TSS2_RC_SUCCESS) + return log_error_errno(SYNTHETIC_ERRNO(ENOTRECOVERABLE), + "Failed to get handle index: %s", sym_Tss2_RC_Decode(rc)); + + return 0; +} + +/* Copy an object in the TPM at a transient handle to a persistent handle. * - * The provided transient handle must exist in the TPM in the transient range. The persistent location may be - * 0 or any location in the persistent range. If 0, this will try each handle in the persistent range, in - * ascending order, until an available one is found. If non-zero, only the requested persistent location will + * The provided transient handle must exist in the TPM in the transient range. The persistent handle may be 0 + * or any handle in the persistent range. If 0, this will try each handle in the persistent range, in + * ascending order, until an available one is found. If non-zero, only the requested persistent handle will * be used. * + * Note that the persistent handle parameter is an handle index (i.e. number), while the transient handle is + * a Tpm2Handle object. The returned persistent handle will be a Tpm2Handle object that is located in the TPM + * at the requested persistent handle index (or the first available if none was requested). + * * Returns 1 if the object was successfully persisted, or 0 if there is already a key at the requested - * location(s), or < 0 on error. The persistent handle is only provided when returning 1. */ + * handle, or < 0 on error. Theoretically, this would also return 0 if no specific persistent handle is + * requiested but all persistent handles are used, but it is extremely unlikely the TPM has enough internal + * memory to store the entire persistent range, in which case an error will be returned if the TPM is out of + * memory for persistent storage. The persistent handle is only provided when returning 1. */ static int tpm2_persist_handle( Tpm2Context *c, const Tpm2Handle *transient_handle, const Tpm2Handle *session, - TPMI_DH_PERSISTENT persistent_location, + TPMI_DH_PERSISTENT persistent_handle_index, Tpm2Handle **ret_persistent_handle) { /* We don't use TPM2_PERSISTENT_FIRST and TPM2_PERSISTENT_LAST here due to: @@ -806,13 +855,13 @@ static int tpm2_persist_handle( assert(c); assert(transient_handle); - /* If persistent location specified, only try that. */ - if (persistent_location != 0) { - if (TPM2_HANDLE_TYPE(persistent_location) != TPM2_HT_PERSISTENT) + /* If persistent handle index specified, only try that. */ + if (persistent_handle_index != 0) { + if (TPM2_HANDLE_TYPE(persistent_handle_index) != TPM2_HT_PERSISTENT) return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), - "Handle not in persistent range: 0x%x", persistent_location); + "Handle not in persistent range: 0x%x", persistent_handle_index); - first = last = persistent_location; + first = last = persistent_handle_index; } for (TPMI_DH_PERSISTENT requested = first; requested <= last; requested++) { @@ -910,7 +959,7 @@ static int tpm2_credit_random(Tpm2Context *c) { return 0; } -static int tpm2_read_public( +int tpm2_read_public( Tpm2Context *c, const Tpm2Handle *session, const Tpm2Handle *handle, @@ -1122,36 +1171,7 @@ static int tpm2_get_srk( TPM2B_NAME **ret_qname, Tpm2Handle **ret_handle) { - int r; - - assert(c); - - _cleanup_(tpm2_handle_freep) Tpm2Handle *handle = NULL; - r = tpm2_esys_handle_from_tpm_handle(c, session, TPM2_SRK_HANDLE, &handle); - if (r < 0) - return r; - if (r == 0) { /* SRK not found */ - if (ret_public) - *ret_public = NULL; - if (ret_name) - *ret_name = NULL; - if (ret_qname) - *ret_qname = NULL; - if (ret_handle) - *ret_handle = NULL; - return 0; - } - - if (ret_public || ret_name || ret_qname) { - r = tpm2_read_public(c, session, handle, ret_public, ret_name, ret_qname); - if (r < 0) - return r; - } - - if (ret_handle) - *ret_handle = TAKE_PTR(handle); - - return 1; + return tpm2_index_to_handle(c, TPM2_SRK_HANDLE, session, ret_public, ret_name, ret_qname, ret_handle); } /* Get the SRK, creating one if needed. Returns 0 on success, or < 0 on error. */ @@ -3752,6 +3772,138 @@ int tpm2_tpm2b_public_from_pem(const void *pem, size_t pem_size, TPM2B_PUBLIC *r #endif } +/* Marshal the public and private objects into a single nonstandard 'blob'. This is not a (publicly) standard + * format, this is specific to how we currently store the sealed object. This 'blob' can be unmarshalled by + * tpm2_unmarshal_blob(). */ +int tpm2_marshal_blob( + const TPM2B_PUBLIC *public, + const TPM2B_PRIVATE *private, + void **ret_blob, + size_t *ret_blob_size) { + + TSS2_RC rc; + + assert(public); + assert(private); + assert(ret_blob); + assert(ret_blob_size); + + size_t max_size = sizeof(*private) + sizeof(*public); + + _cleanup_free_ void *blob = malloc(max_size); + if (!blob) + return log_oom_debug(); + + size_t blob_size = 0; + rc = sym_Tss2_MU_TPM2B_PRIVATE_Marshal(private, blob, max_size, &blob_size); + if (rc != TSS2_RC_SUCCESS) + return log_debug_errno(SYNTHETIC_ERRNO(ENOTRECOVERABLE), + "Failed to marshal private key: %s", sym_Tss2_RC_Decode(rc)); + + rc = sym_Tss2_MU_TPM2B_PUBLIC_Marshal(public, blob, max_size, &blob_size); + if (rc != TSS2_RC_SUCCESS) + return log_debug_errno(SYNTHETIC_ERRNO(ENOTRECOVERABLE), + "Failed to marshal public key: %s", sym_Tss2_RC_Decode(rc)); + + *ret_blob = TAKE_PTR(blob); + *ret_blob_size = blob_size; + + return 0; +} + +/* Unmarshal the 'blob' into public and private objects. This is not a (publicly) standard format, this is + * specific to how we currently store the sealed object. This expects the 'blob' to have been created by + * tpm2_marshal_blob(). */ +int tpm2_unmarshal_blob( + const void *blob, + size_t blob_size, + TPM2B_PUBLIC *ret_public, + TPM2B_PRIVATE *ret_private) { + + TSS2_RC rc; + + assert(blob); + assert(ret_public); + assert(ret_private); + + TPM2B_PRIVATE private = {}; + size_t offset = 0; + rc = sym_Tss2_MU_TPM2B_PRIVATE_Unmarshal(blob, blob_size, &offset, &private); + if (rc != TSS2_RC_SUCCESS) + return log_debug_errno(SYNTHETIC_ERRNO(ENOTRECOVERABLE), + "Failed to unmarshal private key: %s", sym_Tss2_RC_Decode(rc)); + + TPM2B_PUBLIC public = {}; + rc = sym_Tss2_MU_TPM2B_PUBLIC_Unmarshal(blob, blob_size, &offset, &public); + if (rc != TSS2_RC_SUCCESS) + return log_debug_errno(SYNTHETIC_ERRNO(ENOTRECOVERABLE), + "Failed to unmarshal public key: %s", sym_Tss2_RC_Decode(rc)); + + *ret_public = public; + *ret_private = private; + + return 0; +} + +/* Serialize a handle. This produces a binary object that can be later deserialized (by the same TPM), even + * across restarts of the TPM or reboots (assuming the handle is persistent). */ +static int tpm2_serialize( + Tpm2Context *c, + const Tpm2Handle *handle, + void **ret_serialized, + size_t *ret_serialized_size) { + + TSS2_RC rc; + + assert(c); + assert(handle); + assert(ret_serialized); + assert(ret_serialized_size); + + _cleanup_(Esys_Freep) unsigned char *serialized = NULL; + size_t size = 0; + rc = sym_Esys_TR_Serialize(c->esys_context, handle->esys_handle, &serialized, &size); + if (rc != TSS2_RC_SUCCESS) + return log_error_errno(SYNTHETIC_ERRNO(ENOTRECOVERABLE), + "Failed to serialize: %s", sym_Tss2_RC_Decode(rc)); + + *ret_serialized = TAKE_PTR(serialized); + *ret_serialized_size = size; + + return 0; +} + +static int tpm2_deserialize( + Tpm2Context *c, + const void *serialized, + size_t serialized_size, + Tpm2Handle **ret_handle) { + + TSS2_RC rc; + int r; + + assert(c); + assert(serialized); + assert(ret_handle); + + _cleanup_(tpm2_handle_freep) Tpm2Handle *handle = NULL; + r = tpm2_handle_new(c, &handle); + if (r < 0) + return r; + + /* Since this is an existing handle in the TPM we should not implicitly flush it. */ + handle->flush = false; + + rc = sym_Esys_TR_Deserialize(c->esys_context, serialized, serialized_size, &handle->esys_handle); + if (rc != TSS2_RC_SUCCESS) + return log_error_errno(SYNTHETIC_ERRNO(ENOTRECOVERABLE), + "Failed to deserialize: %s", sym_Tss2_RC_Decode(rc)); + + *ret_handle = TAKE_PTR(handle); + + return 0; +} + int tpm2_seal(Tpm2Context *c, const TPM2B_DIGEST *policy, const char *pin, @@ -3764,7 +3916,6 @@ int tpm2_seal(Tpm2Context *c, size_t *ret_srk_buf_size) { uint16_t primary_alg = 0; - TSS2_RC rc; int r; assert(ret_secret); @@ -3889,50 +4040,32 @@ int tpm2_seal(Tpm2Context *c, log_debug("Marshalling private and public part of HMAC key."); _cleanup_free_ void *blob = NULL; - size_t max_size = sizeof(*private) + sizeof(*public), blob_size = 0; - - blob = malloc0(max_size); - if (!blob) - return log_oom(); - - rc = sym_Tss2_MU_TPM2B_PRIVATE_Marshal(private, blob, max_size, &blob_size); - if (rc != TSS2_RC_SUCCESS) - return log_error_errno(SYNTHETIC_ERRNO(ENOTRECOVERABLE), - "Failed to marshal private key: %s", sym_Tss2_RC_Decode(rc)); - - rc = sym_Tss2_MU_TPM2B_PUBLIC_Marshal(public, blob, max_size, &blob_size); - if (rc != TSS2_RC_SUCCESS) - return log_error_errno(SYNTHETIC_ERRNO(ENOTRECOVERABLE), - "Failed to marshal public key: %s", sym_Tss2_RC_Decode(rc)); - - /* serialize the key for storage in the LUKS header. A deserialized ESYS_TR provides both - * the raw TPM handle as well as the object name. The object name is used to verify that - * the key we use later is the key we expect to establish the session with. - */ - _cleanup_(Esys_Freep) uint8_t *srk_buf = NULL; - size_t srk_buf_size = 0; - if (ret_srk_buf) { - log_debug("Serializing SRK ESYS_TR reference"); - rc = sym_Esys_TR_Serialize(c->esys_context, primary_handle->esys_handle, &srk_buf, &srk_buf_size); - if (rc != TSS2_RC_SUCCESS) - return log_error_errno(SYNTHETIC_ERRNO(ENOTRECOVERABLE), - "Failed to serialize primary key: %s", sym_Tss2_RC_Decode(rc)); - } + size_t blob_size; + r = tpm2_marshal_blob(public, private, &blob, &blob_size); + if (r < 0) + return log_error_errno(r, "Could not create sealed blob: %m"); if (DEBUG_LOGGING) log_debug("Completed TPM2 key sealing in %s.", FORMAT_TIMESPAN(now(CLOCK_MONOTONIC) - start, 1)); + _cleanup_free_ void *srk_buf = NULL; + size_t srk_buf_size = 0; if (ret_srk_buf) { + _cleanup_(Esys_Freep) void *tmp = NULL; + r = tpm2_serialize(c, primary_handle, &tmp, &srk_buf_size); + if (r < 0) + return r; + /* * make a copy since we don't want the caller to understand that * ESYS allocated the pointer. It would make tracking what deallocator * to use for srk_buf in which context a PITA. */ - void *tmp = memdup(srk_buf, srk_buf_size); - if (!tmp) + srk_buf = memdup(tmp, srk_buf_size); + if (!srk_buf) return log_oom(); - *ret_srk_buf = TAKE_PTR(tmp); + *ret_srk_buf = TAKE_PTR(srk_buf); *ret_srk_buf_size = srk_buf_size; } @@ -3994,22 +4127,11 @@ int tpm2_unseal(const char *device, usec_t start = now(CLOCK_MONOTONIC); - log_debug("Unmarshalling private part of HMAC key."); - - TPM2B_PRIVATE private = {}; - size_t offset = 0; - rc = sym_Tss2_MU_TPM2B_PRIVATE_Unmarshal(blob, blob_size, &offset, &private); - if (rc != TSS2_RC_SUCCESS) - return log_error_errno(SYNTHETIC_ERRNO(ENOTRECOVERABLE), - "Failed to unmarshal private key: %s", sym_Tss2_RC_Decode(rc)); - - log_debug("Unmarshalling public part of HMAC key."); - - TPM2B_PUBLIC public = {}; - rc = sym_Tss2_MU_TPM2B_PUBLIC_Unmarshal(blob, blob_size, &offset, &public); - if (rc != TSS2_RC_SUCCESS) - return log_error_errno(SYNTHETIC_ERRNO(ENOTRECOVERABLE), - "Failed to unmarshal public key: %s", sym_Tss2_RC_Decode(rc)); + TPM2B_PUBLIC public; + TPM2B_PRIVATE private; + r = tpm2_unmarshal_blob(blob, blob_size, &public, &private); + if (r < 0) + return log_error_errno(r, "Could not extract parts from blob: %m"); _cleanup_(tpm2_context_unrefp) Tpm2Context *c = NULL; r = tpm2_context_new(device, &c); @@ -4026,21 +4148,9 @@ int tpm2_unseal(const char *device, _cleanup_(tpm2_handle_freep) Tpm2Handle *primary_handle = NULL; if (srk_buf) { - r = tpm2_handle_new(c, &primary_handle); + r = tpm2_deserialize(c, srk_buf, srk_buf_size, &primary_handle); if (r < 0) return r; - - primary_handle->flush = false; - - log_debug("Found existing SRK key to use, deserializing ESYS_TR"); - rc = sym_Esys_TR_Deserialize( - c->esys_context, - srk_buf, - srk_buf_size, - &primary_handle->esys_handle); - if (rc != TSS2_RC_SUCCESS) - return log_error_errno(SYNTHETIC_ERRNO(ENOTRECOVERABLE), - "Failed to deserialize primary key: %s", sym_Tss2_RC_Decode(rc)); } else if (primary_alg != 0) { TPM2B_PUBLIC template = { .size = sizeof(TPMT_PUBLIC), }; r = tpm2_get_legacy_template(primary_alg, &template.publicArea); diff --git a/src/shared/tpm2-util.h b/src/shared/tpm2-util.h index 35bcd62759..7253372293 100644 --- a/src/shared/tpm2-util.h +++ b/src/shared/tpm2-util.h @@ -171,6 +171,11 @@ void tpm2_log_debug_buffer(const void *buffer, size_t size, const char *msg); void tpm2_log_debug_digest(const TPM2B_DIGEST *digest, const char *msg); void tpm2_log_debug_name(const TPM2B_NAME *name, const char *msg); +int tpm2_index_to_handle(Tpm2Context *c, TPM2_HANDLE index, const Tpm2Handle *session, TPM2B_PUBLIC **ret_public, TPM2B_NAME **ret_name, TPM2B_NAME **ret_qname, Tpm2Handle **ret_handle); +int tpm2_index_from_handle(Tpm2Context *c, const Tpm2Handle *handle, TPM2_HANDLE *ret_index); + +int tpm2_read_public(Tpm2Context *c, const Tpm2Handle *session, const Tpm2Handle *handle, TPM2B_PUBLIC **ret_public, TPM2B_NAME **ret_name, TPM2B_NAME **ret_qname); + int tpm2_pcr_read(Tpm2Context *c, const TPML_PCR_SELECTION *pcr_selection, Tpm2PCRValue **ret_pcr_values, size_t *ret_n_pcr_values); int tpm2_pcr_read_missing_values(Tpm2Context *c, Tpm2PCRValue *pcr_values, size_t n_pcr_values); @@ -180,6 +185,9 @@ int tpm2_calculate_policy_authorize(const TPM2B_PUBLIC *public, const TPM2B_DIGE int tpm2_calculate_policy_pcr(const Tpm2PCRValue *pcr_values, size_t n_pcr_values, TPM2B_DIGEST *digest); int tpm2_calculate_sealing_policy(const Tpm2PCRValue *pcr_values, size_t n_pcr_values, const TPM2B_PUBLIC *public, bool use_pin, TPM2B_DIGEST *digest); +int tpm2_marshal_blob(const TPM2B_PUBLIC *public, const TPM2B_PRIVATE *private, void **ret_blob, size_t *ret_blob_size); +int tpm2_unmarshal_blob(const void *blob, size_t blob_size, TPM2B_PUBLIC *ret_public, TPM2B_PRIVATE *ret_private); + int tpm2_seal(Tpm2Context *c, const TPM2B_DIGEST *policy, const char *pin, void **ret_secret, size_t *ret_secret_size, void **ret_blob, size_t *ret_blob_size, uint16_t *ret_primary_alg, void **ret_srk_buf, size_t *ret_srk_buf_size); int tpm2_unseal(const char *device, uint32_t hash_pcr_mask, uint16_t pcr_bank, const void *pubkey, size_t pubkey_size, uint32_t pubkey_pcr_mask, JsonVariant *signature, const char *pin, uint16_t primary_alg, const void *blob, size_t blob_size, const void *policy_hash, size_t policy_hash_size, const void *srk_buf, size_t srk_buf_size, void **ret_secret, size_t *ret_secret_size);