1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
|
=pod
=head1 NAME
X509V3_get_d2i, X509V3_add1_i2d, X509V3_EXT_d2i, X509V3_EXT_i2d,
X509_get_ext_d2i, X509_add1_ext_i2d, X509_CRL_get_ext_d2i,
X509_CRL_add1_ext_i2d, X509_REVOKED_get_ext_d2i,
X509_REVOKED_add1_ext_i2d - X509 extension decode and encode functions
=head1 SYNOPSIS
#include <openssl/x509v3.h>
void *X509V3_get_d2i(STACK_OF(X509_EXTENSION) *x, int nid, int *crit,
int *idx);
int X509V3_add1_i2d(STACK_OF(X509_EXTENSION) **x, int nid, void *value,
int crit, unsigned long flags);
void *X509V3_EXT_d2i(X509_EXTENSION *ext);
X509_EXTENSION *X509V3_EXT_i2d(int ext_nid, int crit, void *ext);
void *X509_get_ext_d2i(X509 *x, int nid, int *crit, int *idx);
int X509_add1_ext_i2d(X509 *x, int nid, void *value, int crit,
unsigned long flags);
void *X509_CRL_get_ext_d2i(X509_CRL *crl, int nid, int *crit, int *idx);
int X509_CRL_add1_ext_i2d(X509_CRL *crl, int nid, void *value, int crit,
unsigned long flags);
void *X509_REVOKED_get_ext_d2i(X509_REVOKED *r, int nid, int *crit, int *idx);
int X509_REVOKED_add1_ext_i2d(X509_REVOKED *r, int nid, void *value, int crit,
unsigned long flags);
STACK_OF(X509_EXTENSION) *X509_get0_extensions(const X509 *x);
STACK_OF(X509_EXTENSION) *X509_CRL_get0_extensions(X509_CRL *crl);
STACK_OF(X509_EXTENSION) *X509_REVOKED_get0_extensions(X509_REVOKED *r);
=head1 DESCRIPTION
X509V3_get_ext_d2i() looks for an extension with OID B<nid> in the extensions
B<x> and, if found, decodes it. If B<idx> is B<NULL> then only one
occurrence of an extension is permissible otherwise the first extension after
index B<*idx> is returned and B<*idx> updated to the location of the extension.
If B<crit> is not B<NULL> then B<*crit> is set to a status value: -2 if the
extension occurs multiple times (this is only returned if B<idx> is B<NULL>),
-1 if the extension could not be found, 0 if the extension is found and is
not critical and 1 if critical. A pointer to an extension specific structure
or B<NULL> is returned.
X509V3_add1_i2d() adds extension B<value> to STACK B<*x> (allocating a new
STACK if necessary) using OID B<nid> and criticality B<crit> according
to B<flags>.
X509V3_EXT_d2i() attempts to decode the ASN.1 data contained in extension
B<ext> and returns a pointer to an extension specific structure or B<NULL>
if the extension could not be decoded (invalid syntax or not supported).
X509V3_EXT_i2d() encodes the extension specific structure B<ext>
with OID B<ext_nid> and criticality B<crit>.
X509_get_ext_d2i() and X509_add1_ext_i2d() operate on the extensions of
certificate B<x>, they are otherwise identical to X509V3_get_d2i() and
X509V3_add_i2d().
X509_CRL_get_ext_d2i() and X509_CRL_add1_ext_i2d() operate on the extensions
of CRL B<crl>, they are otherwise identical to X509V3_get_d2i() and
X509V3_add_i2d().
X509_REVOKED_get_ext_d2i() and X509_REVOKED_add1_ext_i2d() operate on the
extensions of B<X509_REVOKED> structure B<r> (i.e for CRL entry extensions),
they are otherwise identical to X509V3_get_d2i() and X509V3_add_i2d().
X509_get0_extensions(), X509_CRL_get0_extensions() and
X509_REVOKED_get0_extensions() return a stack of all the extensions
of a certificate a CRL or a CRL entry respectively.
=head1 NOTES
In almost all cases an extension can occur at most once and multiple
occurences is an error. Therefore the B<idx> parameter is usually B<NULL>.
The B<flags> parameter may be one of the following values.
B<X509V3_ADD_DEFAULT> appends a new extension only if the extension does
not already exist. An error is returned if the extension does already
exist.
B<X509V3_ADD_APPEND> appends a new extension, ignoring whether the extension
already exists.
B<X509V3_ADD_REPLACE> replaces an extension if it exists otherwise apppends
a new extension.
B<X509V3_ADD_REPLACE_EXISTING> replaces an existing extension if it exists
otherwise returns an error.
B<X509V3_ADD_KEEP_EXISTING> appends a new extension only if the extension does
not already exist. An error B<is not> returned if the extension does already
exist.
B<X509V3_ADD_DELETE> extension B<nid> is deleted: no new extenion is added.
If B<X509V3_ADD_SILENT> is ored with B<flags>: any error returned will not
be added to the error queue.
The function X509V3_get_d2i() will return B<NULL> if the extension is not
found, occurs multiple times or cannot be decoded. It is possible to
determine the precise reason by checking the value of B<*crit>.
=head1 SUPPORTED EXTENSIONS
The following sections contain a list of all supported extensions
including their name and NID.
=head2 PKIX CERTIFICATE EXTENSIONS
The following certificate extensions are defined in PKIX standards such as
RFC5280.
Basic Constraints NID_basic_constraints
Key Usage NID_key_usage
Extended Key Usage NID_ext_key_usage
Subject Key Identifier NID_subject_key_identifier
Authority Key Identifier NID_authority_key_identifier
Private Key Usage Period NID_private_key_usage_period
Subject Alternative Name NID_subject_alt_name
Issuer Alternative Name NID_issuer_alt_name
Authority Information Access NID_info_access
Subject Information Access NID_sinfo_access
Name Constraints NID_name_constraints
Certificate Policies NID_certificate_policies
Policy Mappings NID_policy_mappings
Policy Constraints NID_policy_constraints
Inhibit Any Policy NID_inhibit_any_policy
TLS Feature NID_tlsfeature
=head2 NETSCAPE CERTIFICATE EXTENSIONS
The following are (largely obsolete) Netscape certificate extensions.
Netscape Cert Type NID_netscape_cert_type
Netscape Base Url NID_netscape_base_url
Netscape Revocation Url NID_netscape_revocation_url
Netscape CA Revocation Url NID_netscape_ca_revocation_url
Netscape Renewal Url NID_netscape_renewal_url
Netscape CA Policy Url NID_netscape_ca_policy_url
Netscape SSL Server Name NID_netscape_ssl_server_name
Netscape Comment NID_netscape_comment
=head2 MISCELLANEOUS CERTIFICATE EXTENSIONS
Strong Extranet ID NID_sxnet
Proxy Certificate Information NID_proxyCertInfo
=head2 PKIX CRL EXTENSIONS
The following are CRL extensions from PKIX standards such as RFC5280.
CRL Number NID_crl_number
CRL Distribution Points NID_crl_distribution_points
Delta CRL Indicator NID_delta_crl
Freshest CRL NID_freshest_crl
Invalidity Date NID_invalidity_date
Issuing Distrubution Point NID_issuing_distribution_point
The following are CRL entry extensions from PKIX standards such as RFC5280.
CRL Reason Code NID_crl_reason
Certificate Issuer NID_certificate_issuer
=head2 OCSP EXTENSIONS
OCSP Nonce NID_id_pkix_OCSP_Nonce
OCSP CRL ID NID_id_pkix_OCSP_CrlID
Acceptable OCSP Responses NID_id_pkix_OCSP_acceptableResponses
OCSP No Check NID_id_pkix_OCSP_noCheck
OCSP Archive Cutoff NID_id_pkix_OCSP_archiveCutoff
OCSP Service Locator NID_id_pkix_OCSP_serviceLocator
Hold Instruction Code NID_hold_instruction_code
=head2 CERTIFICATE TRANSPARENCY EXTENSIONS
The following extensions are used by certificate transparency, RFC6962
CT Precertificate SCTs NID_ct_precert_scts
CT Certificate SCTs NID_ct_cert_scts
=head1 RETURN VALUES
X509V3_EXT_d2i() and *X509V3_get_d2i() return a pointer to an extension
specific structure of B<NULL> if an error occurs.
X509V3_EXT_i2d() returns a pointer to an B<X509_EXTENSION> structure
or B<NULL> if an error occurs.
X509V3_add1_i2d() returns 1 if the operation is successful and 0 if it
fails due to a non-fatal error (extension not found, already exists,
cannot be encoded) or -1 due to a fatal error such as a memory allocation
failure.
X509_get0_extensions(), X509_CRL_get0_extensions() and
X509_REVOKED_get0_extensions() return a stack of extensions. They can return
NULL if no extensions are present.
=head1 SEE ALSO
L<d2i_X509(3)>,
L<ERR_get_error(3)|ERR_get_error(3)>,
L<X509_CRL_get0_by_serial(3)>,
L<X509_get0_signature(3)>,
L<X509_get_ext_d2i(3)>,
L<X509_get_extension_flags(3)>,
L<X509_get_pubkey(3)>,
L<X509_get_subject_name(3)>,
L<X509_get_version(3)>,
L<X509_NAME_add_entry_by_txt(3)>,
L<X509_NAME_ENTRY_get_object(3)>,
L<X509_NAME_get_index_by_NID(3)>,
L<X509_NAME_print_ex(3)>,
L<X509_new(3)>,
L<X509_sign(3)>,
L<X509_verify_cert(3)>
=cut
|