SM3: Add SM3 hash function

SM3 is a secure hash function which is part of the Chinese
"Commercial Cryptography" suite of algorithms which use is
required for certain commercial applications in China.

Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4616)

1 files changed, 76 insertions, 0 deletions

diff --git a/doc/man3/SM3.pod b/doc/man3/SM3.pod
new file mode 100644
index 0000000000..afa7082618
--- /dev/null
+++ b/doc/man3/SM3.pod
@@ -0,0 +1,76 @@
+=pod
+
+=head1 NAME
+
+SM3_Init,
+SM3_Update,
+SM3_Final
+
+=head1 SYNOPSIS
+
+ #include <openssl/sm3.h>
+
+ unsigned char *SM3(const unsigned char *d, size_t n, unsigned char *md);
+
+ int SM3_Init(SM3_CTX *c);
+ int SM3_Update(SM3_CTX *c, const void *data, size_t len);
+ int SM3_Final(unsigned char *md, SM3_CTX *c);
+
+=head1 DESCRIPTION
+
+SM3 is a cryptographic hash function with a 256-bit output, defined in GB/T
+32905-2016.
+
+SM3() computes the SM3 message digest of the B<n> bytes at B<d> and places it
+in B<md> (which must have space for SM3_DIGEST_LENGTH == 32 bytes of output).
+If B<md> is NULL, the digest is placed in a static array.
+
+The following functions may be used if the message is not completely stored in
+memory:
+
+SM3_Init() initializes a B<SM3_CTX> structure.
+
+SM3_Update() can be called repeatedly with chunks of the message to be hashed
+(B<len> bytes at B<data>).
+
+SM3_Final() places the message digest in B<md>, which must have space for
+B<SM3_DIGEST_LENGTH> == 32 bytes of output, and erases the B<SM3_CTX>.
+
+=head1 RETURN VALUES
+
+=over 4
+
+=item SM3()
+
+Returns pointers to the hash value.
+
+=item SM3_Init(), SM3_Update(), SM3_Final()
+
+Returns 1 for success, 0 otherwise.
+
+=back
+
+=head1 NOTE
+
+Applications should use the higher level functions such as L<EVP_DigestInit(3)>
+instead of calling these functions directly.
+
+=head1 CONFORMING TO
+
+GB/T 32905-2016 and GM/T 0004-2012.
+
+=head1 SEE ALSO
+
+L<EVP_DigestInit(3)>
+
+=head1 COPYRIGHT
+
+Copyright 2017 The OpenSSL Project Authors. All Rights Reserved.
+Copyright 2017 Ribose Inc. 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