xref: /openssl/doc/man3/SCT_validate.pod (revision 4746f25a)
1=pod
2
3=head1 NAME
4
5SCT_validate, SCT_LIST_validate, SCT_get_validation_status -
6checks Signed Certificate Timestamps (SCTs) are valid
7
8=head1 SYNOPSIS
9
10 #include <openssl/ct.h>
11
12 typedef enum {
13     SCT_VALIDATION_STATUS_NOT_SET,
14     SCT_VALIDATION_STATUS_UNKNOWN_LOG,
15     SCT_VALIDATION_STATUS_VALID,
16     SCT_VALIDATION_STATUS_INVALID,
17     SCT_VALIDATION_STATUS_UNVERIFIED,
18     SCT_VALIDATION_STATUS_UNKNOWN_VERSION
19 } sct_validation_status_t;
20
21 int SCT_validate(SCT *sct, const CT_POLICY_EVAL_CTX *ctx);
22 int SCT_LIST_validate(const STACK_OF(SCT) *scts, CT_POLICY_EVAL_CTX *ctx);
23 sct_validation_status_t SCT_get_validation_status(const SCT *sct);
24
25=head1 DESCRIPTION
26
27SCT_validate() will check that an SCT is valid and verify its signature.
28SCT_LIST_validate() performs the same checks on an entire stack of SCTs.
29The result of the validation checks can be obtained by passing the SCT to
30SCT_get_validation_status().
31
32A CT_POLICY_EVAL_CTX must be provided that specifies:
33
34=over 2
35
36=item *
37
38The certificate the SCT was issued for.
39
40Failure to provide the certificate will result in the validation status being
41SCT_VALIDATION_STATUS_UNVERIFIED.
42
43=item *
44
45The issuer of that certificate.
46
47This is only required if the SCT was issued for a pre-certificate
48(see RFC 6962). If it is required but not provided, the validation status will
49be SCT_VALIDATION_STATUS_UNVERIFIED.
50
51=item *
52
53A CTLOG_STORE that contains the CT log that issued this SCT.
54
55If the SCT was issued by a log that is not in this CTLOG_STORE, the validation
56status will be SCT_VALIDATION_STATUS_UNKNOWN_LOG.
57
58=back
59
60If the SCT is of an unsupported version (only v1 is currently supported), the
61validation status will be SCT_VALIDATION_STATUS_UNKNOWN_VERSION.
62
63If the SCT's signature is incorrect, its timestamp is in the future (relative to
64the time in CT_POLICY_EVAL_CTX), or if it is otherwise invalid, the validation
65status will be SCT_VALIDATION_STATUS_INVALID.
66
67If all checks pass, the validation status will be SCT_VALIDATION_STATUS_VALID.
68
69=head1 NOTES
70
71A return value of 0 from SCT_LIST_validate() should not be interpreted as a
72failure. At a minimum, only one valid SCT may provide sufficient confidence
73that a certificate has been publicly logged.
74
75=head1 RETURN VALUES
76
77SCT_validate() returns a negative integer if an internal error occurs, 0 if the
78SCT fails validation, or 1 if the SCT passes validation.
79
80SCT_LIST_validate() returns a negative integer if an internal error occurs, 0
81if any of SCTs fails validation, or 1 if they all pass validation.
82
83SCT_get_validation_status() returns the validation status of the SCT.
84If SCT_validate() or SCT_LIST_validate() have not been passed that SCT, the
85returned value will be SCT_VALIDATION_STATUS_NOT_SET.
86
87=head1 SEE ALSO
88
89L<ct(7)>
90
91=head1 HISTORY
92
93These functions were added in OpenSSL 1.1.0.
94
95=head1 COPYRIGHT
96
97Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
98
99Licensed under the Apache License 2.0 (the "License").  You may not use
100this file except in compliance with the License.  You can obtain a copy
101in the file LICENSE in the source distribution or at
102L<https://www.openssl.org/source/license.html>.
103
104=cut
105