void SCT_print(const SCT *sct, BIO *out, int indent,
const CTLOG_STORE *log_store)
{
const CTLOG *log = NULL;
if (log_store != NULL) {
log = CTLOG_STORE_get0_log_by_id(log_store, sct->log_id,
sct->log_id_len);
}
BIO_printf(out, "%*sSigned Certificate Timestamp:", indent, "");
BIO_printf(out, "\n%*sVersion : ", indent + 4, "");
if (sct->version != SCT_VERSION_V1) {
BIO_printf(out, "unknown\n%*s", indent + 16, "");
BIO_hex_string(out, indent + 16, 16, sct->sct, sct->sct_len);
return;
}
BIO_printf(out, "v1 (0x0)");
if (log != NULL) {
BIO_printf(out, "\n%*sLog : %s", indent + 4, "",
CTLOG_get0_name(log));
}
BIO_printf(out, "\n%*sLog ID : ", indent + 4, "");
BIO_hex_string(out, indent + 16, 16, sct->log_id, sct->log_id_len);
BIO_printf(out, "\n%*sTimestamp : ", indent + 4, "");
timestamp_print(sct->timestamp, out);
BIO_printf(out, "\n%*sExtensions: ", indent + 4, "");
if (sct->ext_len == 0)
BIO_printf(out, "none");
else
BIO_hex_string(out, indent + 16, 16, sct->ext, sct->ext_len);
BIO_printf(out, "\n%*sSignature : ", indent + 4, "");
SCT_signature_algorithms_print(sct, out);
BIO_printf(out, "\n%*s ", indent + 4, "");
BIO_hex_string(out, indent + 16, 16, sct->sig, sct->sig_len);
}
int SCT_validate(SCT *sct, const CT_POLICY_EVAL_CTX *ctx)
{
int is_sct_valid = -1;
SCT_CTX *sctx = NULL;
X509_PUBKEY *pub = NULL, *log_pkey = NULL;
const CTLOG *log;
/*
* With an unrecognized SCT version we don't know what such an SCT means,
* let alone validate one. So we return validation failure (0).
*/
if (sct->version != SCT_VERSION_V1) {
sct->validation_status = SCT_VALIDATION_STATUS_UNKNOWN_VERSION;
return 0;
}
log = CTLOG_STORE_get0_log_by_id(ctx->log_store,
sct->log_id, sct->log_id_len);
/* Similarly, an SCT from an unknown log also cannot be validated. */
if (log == NULL) {
sct->validation_status = SCT_VALIDATION_STATUS_UNKNOWN_LOG;
return 0;
}
sctx = SCT_CTX_new();
if (sctx == NULL)
goto err;
if (X509_PUBKEY_set(&log_pkey, CTLOG_get0_public_key(log)) != 1)
goto err;
if (SCT_CTX_set1_pubkey(sctx, log_pkey) != 1)
goto err;
if (SCT_get_log_entry_type(sct) == CT_LOG_ENTRY_TYPE_PRECERT) {
EVP_PKEY *issuer_pkey;
if (ctx->issuer == NULL) {
sct->validation_status = SCT_VALIDATION_STATUS_UNVERIFIED;
goto end;
}
issuer_pkey = X509_get0_pubkey(ctx->issuer);
if (X509_PUBKEY_set(&pub, issuer_pkey) != 1)
goto err;
if (SCT_CTX_set1_issuer_pubkey(sctx, pub) != 1)
goto err;
}
/*
* XXX: Potential for optimization. This repeats some idempotent heavy
* lifting on the certificate for each candidate SCT, and appears to not
* use any information in the SCT itself, only the certificate is
* processed. So it may make more sense to to do this just once, perhaps
* associated with the shared (by all SCTs) policy eval ctx.
*
* XXX: Failure here is global (SCT independent) and represents either an
* issue with the certificate (e.g. duplicate extensions) or an out of
* memory condition. When the certificate is incompatible with CT, we just
* mark the SCTs invalid, rather than report a failure to determine the
* validation status. That way, callbacks that want to do "soft" SCT
* processing will not abort handshakes with false positive internal
* errors. Since the function does not distinguish between certificate
* issues (peer's fault) and internal problems (out fault) the safe thing
* to do is to report a validation failure and let the callback or
* application decide what to do.
*/
if (SCT_CTX_set1_cert(sctx, ctx->cert, NULL) != 1)
sct->validation_status = SCT_VALIDATION_STATUS_UNVERIFIED;
else
sct->validation_status = SCT_verify(sctx, sct) == 1 ?
SCT_VALIDATION_STATUS_VALID : SCT_VALIDATION_STATUS_INVALID;
end:
is_sct_valid = sct->validation_status == SCT_VALIDATION_STATUS_VALID;
err:
X509_PUBKEY_free(pub);
X509_PUBKEY_free(log_pkey);
SCT_CTX_free(sctx);
return is_sct_valid;
}
