1=pod
2
3=head1 NAME
4
5x509 - X.509 certificate handling
6
7=head1 SYNOPSIS
8
9 #include <openssl/x509.h>
10
11=head1 DESCRIPTION
12
13A X.509 certificate is a structured grouping of information about
14an individual, a device, or anything one can imagine.  A X.509 CRL
15(certificate revocation list) is a tool to help determine if a
16certificate is still valid.  The exact definition of those can be
17found in the X.509 document from ITU-T, or in RFC3280 from PKIX.
18In OpenSSL, the type X509 is used to express such a certificate, and
19the type X509_CRL is used to express a CRL.
20
21A related structure is a certificate request, defined in PKCS#10 from
22RSA Security, Inc, also reflected in RFC2896.  In OpenSSL, the type
23X509_REQ is used to express such a certificate request.
24
25To handle some complex parts of a certificate, there are the types
26X509_NAME (to express a certificate name), X509_ATTRIBUTE (to express
27a certificate attributes), X509_EXTENSION (to express a certificate
28extension) and a few more.
29
30Finally, there's the supertype X509_INFO, which can contain a CRL, a
31certificate and a corresponding private key.
32
33B<X509_>I<...>, B<d2i_X509_>I<...> and B<i2d_X509_>I<...> handle X.509
34certificates, with some exceptions, shown below.
35
36B<X509_CRL_>I<...>, B<d2i_X509_CRL_>I<...> and B<i2d_X509_CRL_>I<...>
37handle X.509 CRLs.
38
39B<X509_REQ_>I<...>, B<d2i_X509_REQ_>I<...> and B<i2d_X509_REQ_>I<...>
40handle PKCS#10 certificate requests.
41
42B<X509_NAME_>I<...> handle certificate names.
43
44B<X509_ATTRIBUTE_>I<...> handle certificate attributes.
45
46B<X509_EXTENSION_>I<...> handle certificate extensions.
47
48=head1 SEE ALSO
49
50L<X509_NAME_ENTRY_get_object(3)|X509_NAME_ENTRY_get_object(3)>,
51L<X509_NAME_add_entry_by_txt(3)|X509_NAME_add_entry_by_txt(3)>,
52L<X509_NAME_add_entry_by_NID(3)|X509_NAME_add_entry_by_NID(3)>,
53L<X509_NAME_print_ex(3)|X509_NAME_print_ex(3)>,
54L<X509_NAME_new(3)|X509_NAME_new(3)>,
55L<d2i_X509(3)|d2i_X509(3)>,
56L<d2i_X509_ALGOR(3)|d2i_X509_ALGOR(3)>,
57L<d2i_X509_CRL(3)|d2i_X509_CRL(3)>,
58L<d2i_X509_NAME(3)|d2i_X509_NAME(3)>,
59L<d2i_X509_REQ(3)|d2i_X509_REQ(3)>,
60L<d2i_X509_SIG(3)|d2i_X509_SIG(3)>,
61L<crypto(3)|crypto(3)>,
62L<x509v3(3)|x509v3(3)>
63
64=cut
65