CT_POLICY_EVAL_CTX_NEW(3ossl) OpenSSL CT_POLICY_EVAL_CTX_NEW(3ossl)
NAME
CT_POLICY_EVAL_CTX_new_ex, CT_POLICY_EVAL_CTX_new,
CT_POLICY_EVAL_CTX_free, CT_POLICY_EVAL_CTX_get0_cert,
CT_POLICY_EVAL_CTX_set1_cert, CT_POLICY_EVAL_CTX_get0_issuer,
CT_POLICY_EVAL_CTX_set1_issuer, CT_POLICY_EVAL_CTX_get0_log_store,
CT_POLICY_EVAL_CTX_set_shared_CTLOG_STORE, CT_POLICY_EVAL_CTX_get_time,
CT_POLICY_EVAL_CTX_set_time - Encapsulates the data required to
evaluate whether SCTs meet a Certificate Transparency policy
SYNOPSIS
#include <openssl/ct.h>
CT_POLICY_EVAL_CTX *CT_POLICY_EVAL_CTX_new_ex(OSSL_LIB_CTX *libctx,
const char *propq);
CT_POLICY_EVAL_CTX *CT_POLICY_EVAL_CTX_new(void);
void CT_POLICY_EVAL_CTX_free(CT_POLICY_EVAL_CTX *ctx);
X509* CT_POLICY_EVAL_CTX_get0_cert(const CT_POLICY_EVAL_CTX *ctx);
int CT_POLICY_EVAL_CTX_set1_cert(CT_POLICY_EVAL_CTX *ctx, X509 *cert);
X509* CT_POLICY_EVAL_CTX_get0_issuer(const CT_POLICY_EVAL_CTX *ctx);
int CT_POLICY_EVAL_CTX_set1_issuer(CT_POLICY_EVAL_CTX *ctx, X509 *issuer);
const CTLOG_STORE *CT_POLICY_EVAL_CTX_get0_log_store(const CT_POLICY_EVAL_CTX *ctx);
void CT_POLICY_EVAL_CTX_set_shared_CTLOG_STORE(CT_POLICY_EVAL_CTX *ctx,
CTLOG_STORE *log_store);
uint64_t CT_POLICY_EVAL_CTX_get_time(const CT_POLICY_EVAL_CTX *ctx);
void CT_POLICY_EVAL_CTX_set_time(CT_POLICY_EVAL_CTX *ctx, uint64_t time_in_ms);
DESCRIPTION
A CT_POLICY_EVAL_CTX is used by functions that evaluate whether Signed
Certificate Timestamps (SCTs) fulfil a Certificate Transparency (CT)
policy. This policy may be, for example, that at least one valid SCT
is available. To determine this, an SCT's timestamp and signature must
be verified. This requires:
o the public key of the log that issued the SCT
o the certificate that the SCT was issued for
o the issuer certificate (if the SCT was issued for a pre-certificate)
o the current time
The above requirements are met using the setters described below.
CT_POLICY_EVAL_CTX_new_ex() creates an empty policy evaluation context
and associates it with the given library context libctx and property
query string propq.
CT_POLICY_EVAL_CTX_new(3) does the same thing as
CT_POLICY_EVAL_CTX_new_ex() except that it uses the default library
context and property query string.
The CT_POLICY_EVAL_CTX should then be populated using:
o CT_POLICY_EVAL_CTX_set1_cert() to provide the certificate the SCTs
were issued for
Increments the reference count of the certificate.
o CT_POLICY_EVAL_CTX_set1_issuer() to provide the issuer certificate
Increments the reference count of the certificate.
o CT_POLICY_EVAL_CTX_set_shared_CTLOG_STORE() to provide a list of logs
that are trusted as sources of SCTs
Holds a pointer to the CTLOG_STORE, so the CTLOG_STORE must outlive
the CT_POLICY_EVAL_CTX.
o CT_POLICY_EVAL_CTX_set_time() to set the time SCTs should be compared
with to determine if they are valid
The SCT timestamp will be compared to this time to check whether the
SCT was issued in the future. RFC6962 states that "TLS clients MUST
reject SCTs whose timestamp is in the future". By default, this will
be set to 5 minutes in the future (e.g. (time() + 300) * 1000), to
allow for clock drift.
The time should be in milliseconds since the Unix Epoch.
Each setter has a matching getter for accessing the current value.
When no longer required, the CT_POLICY_EVAL_CTX should be passed to
CT_POLICY_EVAL_CTX_free() to delete it. If the argument to
CT_POLICY_EVAL_CTX_free() is NULL, nothing is done.
NOTES
The issuer certificate only needs to be provided if at least one of the
SCTs was issued for a pre-certificate. This will be the case for SCTs
embedded in a certificate (i.e. those in an X.509 extension), but may
not be the case for SCTs found in the TLS SCT extension or OCSP
response.
RETURN VALUES
CT_POLICY_EVAL_CTX_new(3) will return
NULL if malloc fails.
SEE ALSO
ct(7)
HISTORY
CT_POLICY_EVAL_CTX_new_ex was added in OpenSSL 3.0. All other functions
were added in OpenSSL 1.1.0.
COPYRIGHT
Copyright 2016-2024 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the Apache License 2.0 (the "License"). You may not use
this file except in compliance with the License. You can obtain a copy
in the file LICENSE in the source distribution or at
<https://www.openssl.org/source/license.html>.
3.3.2 2024-09-04 CT_POLICY_EVAL_CTX_NEW(3ossl)
openssl 3.3.2 - Generated Sun Sep 8 05:57:18 CDT 2024