7de22360f2417f0edfc5ec630c6165b8b0f7d816
[openssl.git] / doc / crypto / X509_get0_signature.pod
1 =pod
2
3 =head1 NAME
4
5 X509_get0_signature, X509_get_signature_nid, X509_get0_tbs_sigalg,
6 X509_REQ_get0_signature, X509_REQ_get_signature_nid, X509_CRL_get0_signature,
7 X509_CRL_get_signature_nid - signature information
8
9 =head1 SYNOPSIS
10
11  #include <openssl/x509.h>
12
13  void X509_get0_signature(ASN1_BIT_STRING **psig, X509_ALGOR **palg,
14                           const X509 *x);
15  int X509_get_signature_nid(const X509 *x);
16  X509_ALGOR *X509_get0_tbs_sigalg(X509 *x);
17
18  void X509_REQ_get0_signature(ASN1_BIT_STRING **psig, X509_ALGOR **palg,
19                               const X509_REQ *crl);
20  int X509_REQ_get_signature_nid(const X509_REQ *crl);
21
22  void X509_CRL_get0_signature(ASN1_BIT_STRING **psig, X509_ALGOR **palg,
23                               const X509_CRL *crl);
24  int X509_CRL_get_signature_nid(const X509_CRL *crl);
25
26 =head1 DESCRIPTION
27
28 X509_get0_signature() sets B<*psig> to the signature of B<x> and B<*palg>
29 to the signature algorithm of B<x>. The values returned are internal
30 pointers which B<MUST NOT> be freed up after the call.
31
32 X509_get0_tbs_sigalg() returns the signature algorithm in the signed
33 portion of B<x>.
34
35 X509_get_signature_nid() returns the NID corresponding to the signature
36 algorithm of B<x>.
37
38 X509_REQ_get0_signature(), X509_REQ_get_signature_nid()
39 X509_CRL_get0_signature() and X509_CRL_get_signature_nid() perform the
40 same function for certificate requests and CRLs.
41
42 =head1 NOTES
43
44 These functions provide lower level access to signatures in certificates
45 where an application wishes to analyse or generate a signature in a form
46 where X509_sign() et al is not appropriate (for example a non standard
47 or unsupported format).
48
49 =head1 RETURN VALUES
50
51 X509_get_signature_nid(), X509_REQ_get_signature_nid() and
52 X509_CRL_get_signature_nid() return a NID.
53
54 X509_get0_signature(), X509_REQ_get0_signature() and
55 X509_CRL_get0_signature() do not return values.
56
57 =head1 SEE ALSO
58
59 L<d2i_X509(3)>,
60 L<ERR_get_error(3)>,
61 L<X509_CRL_get0_by_serial(3)>,
62 L<X509_get_ext_d2i(3)>,
63 L<X509_get_extension_flags(3)>,
64 L<X509_get_pubkey(3)>,
65 L<X509_get_subject_name(3)>,
66 L<X509_get_version(3)>,
67 L<X509_NAME_add_entry_by_txt(3)>,
68 L<X509_NAME_ENTRY_get_object(3)>,
69 L<X509_NAME_get_index_by_NID(3)>,
70 L<X509_NAME_print_ex(3)>,
71 L<X509_new(3)>,
72 L<X509_sign(3)>,
73 L<X509V3_get_d2i(3)>,
74 L<X509_verify_cert(3)>
75
76 =head1 HISTORY
77
78 X509_get0_signature() and X509_get_signature_nid() were first added to
79 OpenSSL 1.0.2.
80
81 X509_REQ_get0_signature(), X509_REQ_get_signature_nid(),
82 X509_CRL_get0_signature() and X509_CRL_get_signature_nid() were first added
83 to OpenSSL 1.1.0.
84
85 =head1 COPYRIGHT
86
87 Copyright 2015-2016 The OpenSSL Project Authors. All Rights Reserved.
88
89 Licensed under the OpenSSL license (the "License").  You may not use
90 this file except in compliance with the License.  You can obtain a copy
91 in the file LICENSE in the source distribution or at
92 L<https://www.openssl.org/source/license.html>.
93
94 =cut