xref: /freebsd/crypto/openssl/doc/man3/X509_PUBKEY_new.pod (revision 62cfcf62f627e5093fb37026a6d8c98e4d2ef04c)
1=pod
2
3=head1 NAME
4
5X509_PUBKEY_new, X509_PUBKEY_free, X509_PUBKEY_set, X509_PUBKEY_get0,
6X509_PUBKEY_get, d2i_PUBKEY, i2d_PUBKEY, d2i_PUBKEY_bio, d2i_PUBKEY_fp,
7i2d_PUBKEY_fp, i2d_PUBKEY_bio, X509_PUBKEY_set0_param,
8X509_PUBKEY_get0_param - SubjectPublicKeyInfo public key functions
9
10=head1 SYNOPSIS
11
12 #include <openssl/x509.h>
13
14 X509_PUBKEY *X509_PUBKEY_new(void);
15 void X509_PUBKEY_free(X509_PUBKEY *a);
16
17 int X509_PUBKEY_set(X509_PUBKEY **x, EVP_PKEY *pkey);
18 EVP_PKEY *X509_PUBKEY_get0(X509_PUBKEY *key);
19 EVP_PKEY *X509_PUBKEY_get(X509_PUBKEY *key);
20
21 EVP_PKEY *d2i_PUBKEY(EVP_PKEY **a, const unsigned char **pp, long length);
22 int i2d_PUBKEY(EVP_PKEY *a, unsigned char **pp);
23
24 EVP_PKEY *d2i_PUBKEY_bio(BIO *bp, EVP_PKEY **a);
25 EVP_PKEY *d2i_PUBKEY_fp(FILE *fp, EVP_PKEY **a);
26
27 int i2d_PUBKEY_fp(FILE *fp, EVP_PKEY *pkey);
28 int i2d_PUBKEY_bio(BIO *bp, EVP_PKEY *pkey);
29
30 int X509_PUBKEY_set0_param(X509_PUBKEY *pub, ASN1_OBJECT *aobj,
31                            int ptype, void *pval,
32                            unsigned char *penc, int penclen);
33 int X509_PUBKEY_get0_param(ASN1_OBJECT **ppkalg,
34                            const unsigned char **pk, int *ppklen,
35                            X509_ALGOR **pa, X509_PUBKEY *pub);
36
37=head1 DESCRIPTION
38
39The B<X509_PUBKEY> structure represents the ASN.1 B<SubjectPublicKeyInfo>
40structure defined in RFC5280 and used in certificates and certificate requests.
41
42X509_PUBKEY_new() allocates and initializes an B<X509_PUBKEY> structure.
43
44X509_PUBKEY_free() frees up B<X509_PUBKEY> structure B<a>. If B<a> is NULL
45nothing is done.
46
47X509_PUBKEY_set() sets the public key in B<*x> to the public key contained
48in the B<EVP_PKEY> structure B<pkey>. If B<*x> is not NULL any existing
49public key structure will be freed.
50
51X509_PUBKEY_get0() returns the public key contained in B<key>. The returned
52value is an internal pointer which B<MUST NOT> be freed after use.
53
54X509_PUBKEY_get() is similar to X509_PUBKEY_get0() except the reference
55count on the returned key is incremented so it B<MUST> be freed using
56EVP_PKEY_free() after use.
57
58d2i_PUBKEY() and i2d_PUBKEY() decode and encode an B<EVP_PKEY> structure
59using B<SubjectPublicKeyInfo> format. They otherwise follow the conventions of
60other ASN.1 functions such as d2i_X509().
61
62d2i_PUBKEY_bio(), d2i_PUBKEY_fp(), i2d_PUBKEY_bio() and i2d_PUBKEY_fp() are
63similar to d2i_PUBKEY() and i2d_PUBKEY() except they decode or encode using a
64B<BIO> or B<FILE> pointer.
65
66X509_PUBKEY_set0_param() sets the public key parameters of B<pub>. The
67OID associated with the algorithm is set to B<aobj>. The type of the
68algorithm parameters is set to B<type> using the structure B<pval>.
69The encoding of the public key itself is set to the B<penclen>
70bytes contained in buffer B<penc>. On success ownership of all the supplied
71parameters is passed to B<pub> so they must not be freed after the
72call.
73
74X509_PUBKEY_get0_param() retrieves the public key parameters from B<pub>,
75B<*ppkalg> is set to the associated OID and the encoding consists of
76B<*ppklen> bytes at B<*pk>, B<*pa> is set to the associated
77AlgorithmIdentifier for the public key. If the value of any of these
78parameters is not required it can be set to B<NULL>. All of the
79retrieved pointers are internal and must not be freed after the
80call.
81
82=head1 NOTES
83
84The B<X509_PUBKEY> functions can be used to encode and decode public keys
85in a standard format.
86
87In many cases applications will not call the B<X509_PUBKEY> functions
88directly: they will instead call wrapper functions such as X509_get0_pubkey().
89
90=head1 RETURN VALUES
91
92If the allocation fails, X509_PUBKEY_new() returns B<NULL> and sets an error
93code that can be obtained by L<ERR_get_error(3)>.
94
95Otherwise it returns a pointer to the newly allocated structure.
96
97X509_PUBKEY_free() does not return a value.
98
99X509_PUBKEY_get0() and X509_PUBKEY_get() return a pointer to an B<EVP_PKEY>
100structure or B<NULL> if an error occurs.
101
102X509_PUBKEY_set(), X509_PUBKEY_set0_param() and X509_PUBKEY_get0_param()
103return 1 for success and 0 if an error occurred.
104
105=head1 SEE ALSO
106
107L<d2i_X509(3)>,
108L<ERR_get_error(3)>,
109L<X509_get_pubkey(3)>,
110
111=head1 COPYRIGHT
112
113Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
114
115Licensed under the OpenSSL license (the "License").  You may not use
116this file except in compliance with the License.  You can obtain a copy
117in the file LICENSE in the source distribution or at
118L<https://www.openssl.org/source/license.html>.
119
120=cut
121