int check_passthru(tpmcmd_t* tpmcmd) {
TPM_TAG tag;
UINT32 len = 10;
BYTE* ptr;
size_t size;
if(tpmcmd->req_len < 10) {
return false;
}
ptr = tpmcmd->req;
tpm_unmarshal_UINT16(&ptr, &len, &tag);
if (tag == VTPM_TAG_REQ2) {
info("VTPM passthru: %d bytes", (int)tpmcmd->req_len);
tpmfront_cmd(tpmfront_dev, tpmcmd->req, tpmcmd->req_len, &tpmcmd->resp, &size);
tpmcmd->resp_len = size;
info("VTPM passthru return: %d bytes", (int)size);
return true;
}
if (tag == VTPM_TAG_REQ) {
info("VTPM pTPM-cmd: %d bytes", (int)tpmcmd->req_len);
ptr = tpmcmd->req;
tpm_marshal_UINT16(&ptr, &len, TPM_TAG_RQU_COMMAND);
tpmfront_cmd(tpmfront_dev, tpmcmd->req, tpmcmd->req_len, &tpmcmd->resp, &size);
tpmcmd->resp_len = size;
info("VTPM pTPM-cmd return: %d bytes", (int)size);
return true;
}
return false;
}
static int tpm_compute_migration_digest(TPM_PUBKEY *migrationKey,
TPM_MIGRATE_SCHEME migrationScheme,
TPM_NONCE *tpmProof, TPM_DIGEST *digest)
{
tpm_sha1_ctx_t sha1;
UINT32 len = sizeof_TPM_PUBKEY((*migrationKey));
BYTE *buf, *ptr, buf2[2];
buf = ptr = tpm_malloc(len);
if (buf == NULL
|| tpm_marshal_TPM_PUBKEY(&ptr, &len, migrationKey)) {
tpm_free(buf);
return -1;
}
/* compute SHA1 hash */
tpm_sha1_init(&sha1);
tpm_sha1_update(&sha1, buf, sizeof_TPM_PUBKEY((*migrationKey)));
ptr = buf2; len = 2;
tpm_marshal_UINT16(&ptr, &len, migrationScheme);
tpm_sha1_update(&sha1, buf2, 2);
tpm_sha1_update(&sha1, tpmProof->nonce, sizeof(TPM_NONCE));
tpm_sha1_final(&sha1, digest->digest);
tpm_free(buf);
return 0;
}
