NAME
X509_new,
X509_dup, X509_free,
X509_up_ref,
X509_chain_up_ref —
X.509 certificate object
SYNOPSIS
#include
<openssl/x509.h>
X509 *
X509_new(void);
X509 *
X509_dup(X509 *a);
void
X509_free(X509 *a);
int
X509_up_ref(X509 *a);
STACK_OF(X509) *
X509_chain_up_ref(STACK_OF(X509)
*chain);
DESCRIPTION
X509_new()
allocates and initializes an empty X509 object with
reference count 1. It represents an ASN.1 Certificate
structure defined in RFC 5280 section 4.1. It can hold a public key together
with information about the person, organization, device, or function the
associated private key belongs to.
X509_dup()
creates a deep copy of a using
ASN1_item_dup(3), setting the reference count of the copy to
1.
X509_free()
decrements the reference count of the X509 structure
a and frees it up if the reference count reaches 0. If
a is a NULL pointer, no action
occurs.
X509_up_ref()
increments the reference count of a by 1. This
function is useful if a certificate structure is being used by several
different operations each of which will free it up after use: this avoids
the need to duplicate the entire certificate structure.
X509_chain_up_ref()
performs a shallow copy of the given chain using
sk_X509_dup()
and increments the reference count of each contained certificate by 1. Its
purpose is similar to X509_up_ref(): The returned
chain persists after the original is freed.
RETURN VALUES
X509_new() and
X509_dup() return a pointer to the newly allocated
object or NULL if an error occurs; an error code can
be obtained by
ERR_get_error(3).
X509_up_ref() returns 1 for success or 0
for failure.
X509_chain_up_ref() returns the copy of
the chain or NULL if an error
occurs.
SEE ALSO
AUTHORITY_KEYID_new(3), BASIC_CONSTRAINTS_new(3), crypto(3), d2i_X509(3), PKCS8_PRIV_KEY_INFO_new(3), X509_ALGOR_new(3), X509_ATTRIBUTE_new(3), X509_check_ca(3), X509_check_host(3), X509_check_issued(3), X509_check_private_key(3), X509_check_purpose(3), X509_CINF_new(3), X509_cmp(3), X509_CRL_new(3), X509_digest(3), X509_EXTENSION_new(3), X509_get0_notBefore(3), X509_get0_signature(3), X509_get1_email(3), X509_get_ex_new_index(3), X509_get_pubkey(3), X509_get_serialNumber(3), X509_get_subject_name(3), X509_get_version(3), X509_INFO_new(3), X509_NAME_new(3), X509_PUBKEY_new(3), X509_REQ_new(3), X509_SIG_new(3), X509_sign(3), X509_STORE_CTX_new(3), X509_STORE_new(3)
STANDARDS
RFC 5280: Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile
HISTORY
X509_new() and
X509_free() appeared in SSLeay 0.4 or earlier.
X509_dup() first appeared in SSLeay 0.4.4. These
functions have been available since OpenBSD 2.4.
X509_up_ref() first appeared in OpenSSL
1.1.0 and has been available since OpenBSD 6.1.
X509_chain_up_ref() first appeared in
OpenSSL 1.0.2 and has been available since OpenBSD
6.3.
BUGS
The X.509 public key infrastructure and its data types contain too many design bugs to list them. For lots of examples, see the classic X.509 Style Guide that Peter Gutmann published in 2000.