=pod

=head1 NAME

DECLARE_PEM_rw,
PEM_read_CMS,
PEM_read_bio_CMS,
PEM_write_CMS,
PEM_write_bio_CMS,
PEM_write_DHxparams,
PEM_write_bio_DHxparams,
PEM_read_ECPKParameters,
PEM_read_bio_ECPKParameters,
PEM_write_ECPKParameters,
PEM_write_bio_ECPKParameters,
PEM_read_ECPrivateKey,
PEM_write_ECPrivateKey,
PEM_write_bio_ECPrivateKey,
PEM_read_EC_PUBKEY,
PEM_read_bio_EC_PUBKEY,
PEM_write_EC_PUBKEY,
PEM_write_bio_EC_PUBKEY,
PEM_read_NETSCAPE_CERT_SEQUENCE,
PEM_read_bio_NETSCAPE_CERT_SEQUENCE,
PEM_write_NETSCAPE_CERT_SEQUENCE,
PEM_write_bio_NETSCAPE_CERT_SEQUENCE,
PEM_read_PKCS8,
PEM_read_bio_PKCS8,
PEM_write_PKCS8,
PEM_write_bio_PKCS8,
PEM_write_PKCS8_PRIV_KEY_INFO,
PEM_read_bio_PKCS8_PRIV_KEY_INFO,
PEM_read_PKCS8_PRIV_KEY_INFO,
PEM_write_bio_PKCS8_PRIV_KEY_INFO,
PEM_read_SSL_SESSION,
PEM_read_bio_SSL_SESSION,
PEM_write_SSL_SESSION,
PEM_write_bio_SSL_SESSION,
PEM_read_X509_PUBKEY,
PEM_read_bio_X509_PUBKEY,
PEM_write_X509_PUBKEY,
PEM_write_bio_X509_PUBKEY
- PEM object encoding routines

=head1 SYNOPSIS

=for openssl generic

 #include <openssl/pem.h>

 DECLARE_PEM_rw(name, TYPE)

 TYPE *PEM_read_TYPE(FILE *fp, TYPE **a, pem_password_cb *cb, void *u);
 TYPE *PEM_read_bio_TYPE(BIO *bp, TYPE **a, pem_password_cb *cb, void *u);
 int PEM_write_TYPE(FILE *fp, const TYPE *a);
 int PEM_write_bio_TYPE(BIO *bp, const TYPE *a);

The following functions have been deprecated since OpenSSL 3.0, and can be
hidden entirely by defining B<OPENSSL_API_COMPAT> with a suitable version value,
see L<openssl_user_macros(7)>:

 #include <openssl/pem.h>

 int PEM_write_DHxparams(FILE *out, const DH *dh);
 int PEM_write_bio_DHxparams(BIO *out, const DH *dh);
 EC_GROUP *PEM_read_ECPKParameters(FILE *fp, EC_GROUP **x, pem_password_cb *cb, void *u);
 EC_GROUP *PEM_read_bio_ECPKParameters(BIO *bp, EC_GROUP **x, pem_password_cb *cb, void *u);
 int PEM_write_ECPKParameters(FILE *out, const EC_GROUP *x);
 int PEM_write_bio_ECPKParameters(BIO *out, const EC_GROUP *x),

 EC_KEY *PEM_read_EC_PUBKEY(FILE *fp, EC_KEY **x, pem_password_cb *cb, void *u);
 EC_KEY *PEM_read_bio_EC_PUBKEY(BIO *bp, EC_KEY **x, pem_password_cb *cb, void *u);
 int PEM_write_EC_PUBKEY(FILE *out, const EC_KEY *x);
 int PEM_write_bio_EC_PUBKEY(BIO *out, const EC_KEY *x);

 EC_KEY *PEM_read_ECPrivateKey(FILE *out, EC_KEY **x, pem_password_cb *cb, void *u);
 EC_KEY *PEM_read_bio_ECPrivateKey(BIO *out, EC_KEY **x, pem_password_cb *cb, void *u);
 int PEM_write_ECPrivateKey(FILE *out, const EC_KEY *x, const EVP_CIPHER *enc,
                            const unsigned char *kstr, int klen,
                            pem_password_cb *cb, void *u);
 int PEM_write_bio_ECPrivateKey(BIO *out, const EC_KEY *x, const EVP_CIPHER *enc,
                                const unsigned char *kstr, int klen,
                                pem_password_cb *cb, void *u);

=head1 DESCRIPTION

To replace the deprecated functions listed above, applications should use the
B<EVP_PKEY> type and OSSL_DECODER_from_bio() and OSSL_ENCODER_to_bio() to
read and write PEM data containing key parameters or private and public keys.

In the description below, B<I<TYPE>> is used
as a placeholder for any of the OpenSSL datatypes, such as B<X509>.
The macro B<DECLARE_PEM_rw> expands to the set of declarations shown in
the next four lines of the synopsis.

These routines convert between local instances of ASN1 datatypes and
the PEM encoding.  For more information on the templates, see
L<ASN1_ITEM(3)>.  For more information on the lower-level routines used
by the functions here, see L<PEM_read(3)>.

B<PEM_read_I<TYPE>>() reads a PEM-encoded object of B<I<TYPE>> from the file
I<fp> and returns it.  The I<cb> and I<u> parameters are as described in
L<pem_password_cb(3)>.

B<PEM_read_bio_I<TYPE>>() is similar to B<PEM_read_I<TYPE>>() but reads from
the BIO I<bp>.

B<PEM_write_I<TYPE>>() writes the PEM encoding of the object I<a> to the file
I<fp>.

B<PEM_write_bio_I<TYPE>>() similarly writes to the BIO I<bp>.

=head1 NOTES

These functions make no assumption regarding the pass phrase received from the
password callback.
It will simply be treated as a byte sequence.

=head1 RETURN VALUES

B<PEM_read_I<TYPE>>() and B<PEM_read_bio_I<TYPE>>() return a pointer to an
allocated object, which should be released by calling B<I<TYPE>_free>(), or
NULL on error.

B<PEM_write_I<TYPE>>() and B<PEM_write_bio_I<TYPE>>() return 1 for success or 0 for failure.

=head1 SEE ALSO

L<PEM_read(3)>,
L<passphrase-encoding(7)>

=head1 HISTORY

The functions PEM_write_DHxparams(), PEM_write_bio_DHxparams(),
PEM_read_ECPKParameters(), PEM_read_bio_ECPKParameters(),
PEM_write_ECPKParameters(), PEM_write_bio_ECPKParameters(),
PEM_read_EC_PUBKEY(), PEM_read_bio_EC_PUBKEY(),
PEM_write_EC_PUBKEY(), PEM_write_bio_EC_PUBKEY(),
PEM_read_ECPrivateKey(), PEM_read_bio_ECPrivateKey(),
PEM_write_ECPrivateKey() and PEM_write_bio_ECPrivateKey()
were deprecated in OpenSSL 3.0.

=head1 COPYRIGHT

Copyright 1998-2025 The OpenSSL Project Authors. All Rights Reserved.

Licensed under the Apache License 2.0 (the "License").  You may not use
this file except in compliance with the License.  You can obtain a copy
in the file LICENSE in the source distribution or at
L<https://www.openssl.org/source/license.html>.

=cut
