Add PEM_bytes_read_bio_secmem()

[openssl.git] / doc / man3 / PEM_bytes_read_bio.pod

diff --git a/doc/man3/PEM_bytes_read_bio.pod b/doc/man3/PEM_bytes_read_bio.pod
new file mode 100644 (file)
index 0000000..d16ccd8
--- /dev/null
+++ b/doc/man3/PEM_bytes_read_bio.pod
@@ -0,0 +1,81 @@
+=pod
+
+=head1 NAME
+
+PEM_bytes_read_bio, PEM_bytes_read_bio_secmem - read a PEM-encoded data structure from a BIO
+
+=head1 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);
+
+=head1 DESCRIPTION
+
+PEM_bytes_read_bio() reads PEM-formatted (RFC 1421) data from the BIO
+I<bp> for the data type given in I<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 I<cb> and rock I<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 I<*pnm> if I<pnm> is
+non-NULL.  The caller must free the storage pointed to by I<*pnm>.
+
+The returned data is the DER-encoded form of the requested type, in
+I<*pdata> with length I<*plen>.  The caller must free the storage pointed
+to by I<*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 I<*pdata> and I<*pnm>.  Accordingly, the caller must use
+OPENSSL_secure_free() to free that storage.
+
+=head1 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 I<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.
+
+=head1 RETURN VALUES
+
+PEM_bytes_read_bio() and PEM_bytes_read_bio_secmem() return 1 for success or
+0 for failure.
+
+=head1 SEE ALSO
+
+L<PEM(3)>,
+L<PEM_read_bio_ex(3)>
+
+=head1 HISTORY
+
+PEM_bytes_read_bio_secmem() was introduced in OpenSSL 1.1.1
+
+=head1 COPYRIGHT
+
+Copyright 2017 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
+L<https://www.openssl.org/source/license.html>.
+
+=cut