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diff --git a/doc/man3/SMIME_read_PKCS7.pod b/doc/man3/SMIME_read_PKCS7.pod
new file mode 100644
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+++ b/doc/man3/SMIME_read_PKCS7.pod
@@ -0,0 +1,78 @@
+=pod
+
+=head1 NAME
+
+SMIME_read_PKCS7 - parse S/MIME message
+
+=head1 SYNOPSIS
+
+ #include <openssl/pkcs7.h>
+
+ PKCS7 *SMIME_read_PKCS7(BIO *in, BIO **bcont);
+
+=head1 DESCRIPTION
+
+SMIME_read_PKCS7() parses a message in S/MIME format.
+
+B<in> is a BIO to read the message from.
+
+If cleartext signing is used then the content is saved in
+a memory bio which is written to B<*bcont>, otherwise
+B<*bcont> is set to B<NULL>.
+
+The parsed PKCS#7 structure is returned or B<NULL> if an
+error occurred.
+
+=head1 NOTES
+
+If B<*bcont> is not B<NULL> then the message is clear text
+signed. B<*bcont> can then be passed to PKCS7_verify() with
+the B<PKCS7_DETACHED> flag set.
+
+Otherwise the type of the returned structure can be determined
+using PKCS7_type_is_enveloped(), etc.
+
+To support future functionality if B<bcont> is not B<NULL>
+B<*bcont> should be initialized to B<NULL>. For example:
+
+ BIO *cont = NULL;
+ PKCS7 *p7;
+
+ p7 = SMIME_read_PKCS7(in, &cont);
+
+=head1 BUGS
+
+The MIME parser used by SMIME_read_PKCS7() is somewhat primitive.
+While it will handle most S/MIME messages more complex compound
+formats may not work.
+
+The parser assumes that the PKCS7 structure is always base64
+encoded and will not handle the case where it is in binary format
+or uses quoted printable format.
+
+The use of a memory BIO to hold the signed content limits the size
+of message which can be processed due to memory restraints: a
+streaming single pass option should be available.
+
+=head1 RETURN VALUES
+
+SMIME_read_PKCS7() returns a valid B<PKCS7> structure or B<NULL>
+if an error occurred. The error can be obtained from ERR_get_error(3).
+
+=head1 SEE ALSO
+
+L<ERR_get_error(3)>,
+L<SMIME_read_PKCS7(3)>, L<PKCS7_sign(3)>,
+L<PKCS7_verify(3)>, L<PKCS7_encrypt(3)>
+L<PKCS7_decrypt(3)>
+
+=head1 COPYRIGHT
+
+Copyright 2002-2018 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
+L<https://www.openssl.org/source/license.html>.
+
+=cut