NAME

       PEM_bytes_read_bio, PEM_bytes_read_bio_secmem - read a PEM-encoded data structure from a
       BIO

SYNOPSIS

        #include <openssl/pem.h>

        int PEM_bytes_read_bio(unsigned char **pdata, long *plen, char **pnm,
                               const char *name, BIO *bp, pem_password_cb *cb,
                               void *u);
        int PEM_bytes_read_bio_secmem(unsigned char **pdata, long *plen, char **pnm,
                                      const char *name, BIO *bp, pem_password_cb *cb,
                                      void *u);

DESCRIPTION

       PEM_bytes_read_bio() reads PEM-formatted (RFC 1421) data from the BIO bp for the data type
       given in name (RSA PRIVATE KEY, CERTIFICATE, etc.).  If multiple PEM-encoded data
       structures are present in the same stream, PEM_bytes_read_bio() will skip non-matching
       data types and continue reading.  Non-PEM data present in the stream may cause an error.

       The PEM header may indicate that the following data is encrypted; if so, the data will be
       decrypted, waiting on user input to supply a passphrase if needed.  The password callback
       cb and rock u are used to obtain the decryption passphrase, if applicable.

       Some data types have compatibility aliases, such as a file containing X509 CERTIFICATE
       matching a request for the deprecated type CERTIFICATE.  The actual type indicated by the
       file is returned in *pnm if pnm is non-NULL.  The caller must free the storage pointed to
       by *pnm.

       The returned data is the DER-encoded form of the requested type, in *pdata with length
       *plen.  The caller must free the storage pointed to by *pdata.

       PEM_bytes_read_bio_secmem() is similar to PEM_bytes_read_bio(), but uses memory from the
       secure heap for its temporary buffers and the storage returned in *pdata and *pnm.
       Accordingly, the caller must use OPENSSL_secure_free() to free that storage.

NOTES

       PEM_bytes_read_bio_secmem() only enforces that the secure heap is used for storage
       allocated within the PEM processing stack.  The BIO stack from which input is read may
       also use temporary buffers, which are not necessarily allocated from the secure heap.  In
       cases where it is desirable to ensure that the contents of the PEM file only appears in
       memory from the secure heap, care is needed in generating the BIO passed as bp.  In
       particular, the use of BIO_s_file() indicates the use of the operating system stdio
       functionality, which includes buffering as a feature; BIO_s_fd() is likely to be more
       appropriate in such cases.

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

RETURN VALUES

       PEM_bytes_read_bio() and PEM_bytes_read_bio_secmem() return 1 for success or 0 for
       failure.

SEE ALSO

       PEM(3), PEM_read_bio_ex(3), passphrase-encoding(7)

HISTORY

       PEM_bytes_read_bio_secmem() was introduced in OpenSSL 1.1.1

COPYRIGHT

       Copyright 2017-2018 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the OpenSSL license (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 <https://www.openssl.org/source/license.html>.