1=pod 2 3=head1 NAME 4 5CT_POLICY_EVAL_CTX_new_ex, 6CT_POLICY_EVAL_CTX_new, CT_POLICY_EVAL_CTX_free, 7CT_POLICY_EVAL_CTX_get0_cert, CT_POLICY_EVAL_CTX_set1_cert, 8CT_POLICY_EVAL_CTX_get0_issuer, CT_POLICY_EVAL_CTX_set1_issuer, 9CT_POLICY_EVAL_CTX_get0_log_store, CT_POLICY_EVAL_CTX_set_shared_CTLOG_STORE, 10CT_POLICY_EVAL_CTX_get_time, CT_POLICY_EVAL_CTX_set_time - 11Encapsulates the data required to evaluate whether SCTs meet a Certificate Transparency policy 12 13=head1 SYNOPSIS 14 15 #include <openssl/ct.h> 16 17 CT_POLICY_EVAL_CTX *CT_POLICY_EVAL_CTX_new_ex(OSSL_LIB_CTX *libctx, 18 const char *propq); 19 CT_POLICY_EVAL_CTX *CT_POLICY_EVAL_CTX_new(void); 20 void CT_POLICY_EVAL_CTX_free(CT_POLICY_EVAL_CTX *ctx); 21 X509* CT_POLICY_EVAL_CTX_get0_cert(const CT_POLICY_EVAL_CTX *ctx); 22 int CT_POLICY_EVAL_CTX_set1_cert(CT_POLICY_EVAL_CTX *ctx, X509 *cert); 23 X509* CT_POLICY_EVAL_CTX_get0_issuer(const CT_POLICY_EVAL_CTX *ctx); 24 int CT_POLICY_EVAL_CTX_set1_issuer(CT_POLICY_EVAL_CTX *ctx, X509 *issuer); 25 const CTLOG_STORE *CT_POLICY_EVAL_CTX_get0_log_store(const CT_POLICY_EVAL_CTX *ctx); 26 void CT_POLICY_EVAL_CTX_set_shared_CTLOG_STORE(CT_POLICY_EVAL_CTX *ctx, 27 CTLOG_STORE *log_store); 28 uint64_t CT_POLICY_EVAL_CTX_get_time(const CT_POLICY_EVAL_CTX *ctx); 29 void CT_POLICY_EVAL_CTX_set_time(CT_POLICY_EVAL_CTX *ctx, uint64_t time_in_ms); 30 31=head1 DESCRIPTION 32 33A B<CT_POLICY_EVAL_CTX> is used by functions that evaluate whether Signed 34Certificate Timestamps (SCTs) fulfil a Certificate Transparency (CT) policy. 35This policy may be, for example, that at least one valid SCT is available. To 36determine this, an SCT's timestamp and signature must be verified. 37This requires: 38 39=over 2 40 41=item * 42 43the public key of the log that issued the SCT 44 45=item * 46 47the certificate that the SCT was issued for 48 49=item * 50 51the issuer certificate (if the SCT was issued for a pre-certificate) 52 53=item * 54 55the current time 56 57=back 58 59The above requirements are met using the setters described below. 60 61CT_POLICY_EVAL_CTX_new_ex() creates an empty policy evaluation context 62and associates it with the given library context I<libctx> and property query 63string I<propq>. 64 65CT_POLICY_EVAL_CTX_new() does the same thing as 66CT_POLICY_EVAL_CTX_new_ex() except that it uses the default library 67context and property query string. 68 69The CT_POLICY_EVAL_CTX should then be populated using: 70 71=over 2 72 73=item * 74 75CT_POLICY_EVAL_CTX_set1_cert() to provide the certificate the SCTs were issued for 76 77Increments the reference count of the certificate. 78 79=item * 80 81CT_POLICY_EVAL_CTX_set1_issuer() to provide the issuer certificate 82 83Increments the reference count of the certificate. 84 85=item * 86 87CT_POLICY_EVAL_CTX_set_shared_CTLOG_STORE() to provide a list of logs that are trusted as sources of SCTs 88 89Holds a pointer to the CTLOG_STORE, so the CTLOG_STORE must outlive the 90CT_POLICY_EVAL_CTX. 91 92=item * 93 94CT_POLICY_EVAL_CTX_set_time() to set the time SCTs should be compared with to determine if they are valid 95 96The SCT timestamp will be compared to this time to check whether the SCT was 97issued in the future. RFC6962 states that "TLS clients MUST reject SCTs whose 98timestamp is in the future". By default, this will be set to 5 minutes in the 99future (e.g. (time() + 300) * 1000), to allow for clock drift. 100 101The time should be in milliseconds since the Unix Epoch. 102 103=back 104 105Each setter has a matching getter for accessing the current value. 106 107When no longer required, the B<CT_POLICY_EVAL_CTX> should be passed to 108CT_POLICY_EVAL_CTX_free() to delete it. If the argument to 109CT_POLICY_EVAL_CTX_free() is NULL, nothing is done. 110 111=head1 NOTES 112 113The issuer certificate only needs to be provided if at least one of the SCTs 114was issued for a pre-certificate. This will be the case for SCTs embedded in a 115certificate (i.e. those in an X.509 extension), but may not be the case for SCTs 116found in the TLS SCT extension or OCSP response. 117 118=head1 RETURN VALUES 119 120CT_POLICY_EVAL_CTX_new_ex() and CT_POLICY_EVAL_CTX_new() will return 121NULL if malloc fails. 122 123=head1 SEE ALSO 124 125L<ct(7)> 126 127=head1 HISTORY 128 129CT_POLICY_EVAL_CTX_new_ex was added in OpenSSL 3.0. All other 130functions were added in OpenSSL 1.1.0. 131 132=head1 COPYRIGHT 133 134Copyright 2016-2024 The OpenSSL Project Authors. All Rights Reserved. 135 136Licensed under the Apache License 2.0 (the "License"). You may not use 137this file except in compliance with the License. You can obtain a copy 138in the file LICENSE in the source distribution or at 139L<https://www.openssl.org/source/license.html>. 140 141=cut 142