static void compute_key_digest(TPM_REQUEST *req, TPM_DIGEST *digest) { tpm_sha1_ctx_t ctx; TPM_HANDLE h1, h2; TPM_KEY_DATA *k1, *k2; BYTE *ptr; UINT32 len, offset = tpm_get_in_param_offset(req->ordinal); /* handle some exceptions */ if (req->ordinal == TPM_ORD_FlushSpecific) offset = 0; else if (req->ordinal == TPM_ORD_OwnerReadInternalPub) offset = 4; /* compute public key digests */ if (offset == 0) { debug("no handles"); memset(digest, 0, sizeof(TPM_DIGEST)); } else if (offset == 4) { debug("one handle"); ptr = req->param; len = 4; tpm_unmarshal_TPM_HANDLE(&ptr, &len, &h1); k1 = tpm_get_key(h1); if (k1 != NULL && tpm_compute_key_data_digest(k1, digest) == 0) { debug("key found"); /* compute outer hash */ tpm_sha1_init(&ctx); tpm_sha1_update(&ctx, digest->digest, sizeof(digest->digest)); tpm_sha1_final(&ctx, digest->digest); } else { memset(digest, 0, sizeof(TPM_DIGEST)); } } else if (offset == 8) { TPM_DIGEST digest2; debug("two handles"); ptr = req->param; len = 8; tpm_unmarshal_TPM_HANDLE(&ptr, &len, &h1); tpm_unmarshal_TPM_HANDLE(&ptr, &len, &h2); k1 = tpm_get_key(h1); k2 = tpm_get_key(h2); if (k1 != NULL && tpm_compute_key_data_digest(k1, digest) == 0 && k2 != NULL && tpm_compute_key_data_digest(k2, &digest2) == 0) { debug("two keys found"); /* compute outer hash */ tpm_sha1_init(&ctx); tpm_sha1_update(&ctx, digest->digest, sizeof(digest->digest)); tpm_sha1_update(&ctx, digest2.digest, sizeof(digest2.digest)); tpm_sha1_final(&ctx, digest->digest); } else { memset(digest, 0, sizeof(TPM_DIGEST)); } } else { memset(digest, 0, sizeof(TPM_DIGEST)); } }
void tpm_compute_in_param_digest(TPM_REQUEST *req) { tpm_sha1_ctx_t sha1; UINT32 offset = tpm_get_in_param_offset(req->ordinal); /* compute SHA1 hash */ if (offset <= req->paramSize) { tpm_sha1_init(&sha1); tpm_sha1_update_be32(&sha1, req->ordinal); /* skip all handles at the beginning */ tpm_sha1_update(&sha1, req->param + offset, req->paramSize - offset); tpm_sha1_final(&sha1, req->auth1.digest); memcpy(req->auth2.digest, req->auth1.digest, sizeof(req->auth1.digest)); } }
TPM_RESULT TPM_ExecuteTransport(UINT32 inWrappedCmdSize, BYTE *inWrappedCmd, TPM_AUTH *auth1, UINT64 *currentTicks, TPM_MODIFIER_INDICATOR *locality, UINT32 *outWrappedCmdSize, BYTE **outWrappedCmd) { TPM_RESULT res; TPM_SESSION_DATA *session; TPM_REQUEST req; TPM_RESPONSE rsp; BYTE *ptr, buf[4 * 4 + 8 + 20]; UINT32 len, offset; tpm_sha1_ctx_t sha1; info("TPM_ExecuteTransport()"); /* get transport session */ session = tpm_get_transport(auth1->authHandle); if (session == NULL) return TPM_BAD_PARAMETER; /* unmarshal wrapped command */ len = inWrappedCmdSize; ptr = inWrappedCmd; if (tpm_unmarshal_TPM_REQUEST(&ptr, &len, &req)) return TPM_FAIL; /* decrypt wrapped command if needed */ ptr = tpm_malloc(req.paramSize); if (ptr == NULL) return TPM_FAIL; memcpy(ptr, req.param, req.paramSize); if (session->transInternal.transPublic.transAttributes & TPM_TRANSPORT_ENCRYPT) { if (req.ordinal == TPM_ORD_OIAP || req.ordinal == TPM_ORD_OSAP) { offset = req.paramSize; } else if (req.ordinal == TPM_ORD_DSAP) { offset = 30; } else { offset = tpm_get_in_param_offset(req.ordinal); } debug("decrypting %d bytes, starting at pos %d", req.paramSize - offset, offset); decrypt_wrapped_command(ptr + offset, req.paramSize - offset, auth1, session); } req.param = ptr; /* verify authorization */ tpm_compute_in_param_digest(&req); tpm_sha1_init(&sha1); tpm_sha1_update_be32(&sha1, TPM_ORD_ExecuteTransport); tpm_sha1_update_be32(&sha1, inWrappedCmdSize); tpm_sha1_update(&sha1, req.auth1.digest, sizeof(req.auth1.digest)); tpm_sha1_final(&sha1, auth1->digest); res = tpm_verify_auth(auth1, session->transInternal.authData, TPM_INVALID_HANDLE); if (res != TPM_SUCCESS) { tpm_free(req.param); return res; } /* nested transport sessions are not allowed */ if (req.ordinal == TPM_ORD_EstablishTransport || req.ordinal == TPM_ORD_ExecuteTransport || req.ordinal == TPM_ORD_ReleaseTransportSigned) { tpm_free(req.param); return TPM_NO_WRAP_TRANSPORT; } /* log input parameters */ if (session->transInternal.transPublic.transAttributes & TPM_TRANSPORT_LOG) { TPM_DIGEST keyDigest; compute_key_digest(&req, &keyDigest); transport_log_in(req.auth1.digest, keyDigest.digest, &session->transInternal.transDigest); } /* execute and audit command*/ tpm_audit_request(req.ordinal, &req); tpm_execute_command(&req, &rsp); tpm_audit_response(req.ordinal, &rsp); tpm_free(req.param); /* get locality and ticks */ *locality = tpmData.stany.flags.localityModifier; *currentTicks = tpmData.stany.data.currentTicks.currentTicks; /* if required, compute digest of internal output parameters */ debug("result = %d", rsp.result); if (rsp.result == TPM_SUCCESS) { if (rsp.tag == TPM_TAG_RSP_COMMAND) { rsp.auth1 = &req.auth1; tpm_compute_out_param_digest(req.ordinal, &rsp); } /* encrypt parameters */ if (session->transInternal.transPublic.transAttributes & TPM_TRANSPORT_ENCRYPT) { if (req.ordinal == TPM_ORD_OIAP || req.ordinal == TPM_ORD_OSAP) { offset = rsp.paramSize; } else if (req.ordinal == TPM_ORD_DSAP) { offset = rsp.paramSize; } else { offset = tpm_get_out_param_offset(req.ordinal); } debug("encrypting %d bytes, starting at pos %d", rsp.paramSize - offset, offset); encrypt_wrapped_command(rsp.param + offset, rsp.paramSize - offset, auth1, session); } } else { rsp.auth1 = &req.auth1; memset(rsp.auth1->digest, 0, sizeof(*rsp.auth1->digest)); } /* marshal response */ *outWrappedCmdSize = len = rsp.size; *outWrappedCmd = ptr = tpm_malloc(len); if (ptr == NULL) { tpm_free(rsp.param); return TPM_FAIL; } tpm_marshal_TPM_RESPONSE(&ptr, &len, &rsp); debug("marshalling done."); /* log output parameters */ if (session->transInternal.transPublic.transAttributes & TPM_TRANSPORT_LOG) { transport_log_out(rsp.auth1->digest, &session->transInternal.transDigest); } tpm_free(rsp.param); /* compute digest of output parameters */ ptr = buf; len = sizeof(buf); tpm_marshal_UINT32(&ptr, &len, TPM_SUCCESS); tpm_marshal_TPM_COMMAND_CODE(&ptr, &len, TPM_ORD_ExecuteTransport); tpm_marshal_UINT64(&ptr, &len, *currentTicks); tpm_marshal_TPM_MODIFIER_INDICATOR(&ptr, &len, *locality); tpm_marshal_UINT32(&ptr, &len, *outWrappedCmdSize); memcpy(ptr, rsp.auth1->digest, sizeof(rsp.auth1->digest)); tpm_sha1_init(&sha1); tpm_sha1_update(&sha1, buf, sizeof(buf)); tpm_sha1_final(&sha1, auth1->digest); return TPM_SUCCESS; }