PROV: Add the beginning of a DER writing library

[openssl.git] / doc / internal / man3 / DER_w_precompiled.pod

diff --git a/doc/internal/man3/DER_w_precompiled.pod b/doc/internal/man3/DER_w_precompiled.pod
new file mode 100644 (file)
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+++ b/doc/internal/man3/DER_w_precompiled.pod
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+=pod
+
+=head1 NAME
+
+DER_w_precompiled
+- internal DER writers for precompiled DER blobs
+
+=head1 SYNOPSIS
+
+ #include "internal/der.h"
+
+ int DER_w_precompiled(WPACKET *pkt, int tag,
+                       const unsigned char *precompiled,
+                       size_t precompiled_n);
+
+=head1 DESCRIPTION
+
+There may be already existing DER blobs that can simply be copied to
+the buffer held by I<pkt>.  For example, precompiled values, such as
+OIDs (for example, C<id-sha256>) or complete AlgorithmIdentifiers
+(for example, C<sha256Identifier>).  To add those as an element in a
+structure being DER encoded, use DER_w_precompiled().
+
+DER_w_precompiled() will simply take the DER encoded blob given as
+I<precompiled> with length I<precompiled_n> and add it to the buffer
+held by I<pkt>.
+
+=head1 RETURN VALUES
+
+DER_w_precompiled() returns 1 on success and 0 on failure.  Failure
+may mean that the buffer held by the I<pkt> is too small, but may also
+mean that the values given to the functions are invalid, such as the provided
+I<tag> value being too large for the implementation.
+
+=head1 SEE ALSO
+
+L<DERlib(7)>
+
+=head1 COPYRIGHT
+
+Copyright 2020 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