[rng] Remove obsolete (and unfinished) get_random_bytes() function

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/crypto/crandom.c

@@ -1,55 +0,0 @@
-/*
- * Copyright (c) 2009 Joshua Oreman <oremanj@rwcr.net>.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of the
- * License, or any later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-FILE_LICENCE ( GPL2_OR_LATER );
-
-/** @file
- *
- * Cryptographically strong random number generator
- *
- * Currently the cryptographic part is not implemented, and this just
- * uses random().
- */
-
-#include <ipxe/crypto.h>
-#include <stdlib.h>
-
-/**
- * Get cryptographically strong random bytes
- *
- * @v buf	Buffer in which to store random bytes
- * @v len	Number of random bytes to generate
- *
- * @b WARNING: This function is currently underimplemented, and does
- * not give numbers any stronger than random()!
- */
-void get_random_bytes ( void *buf, size_t len )
-{
-	u8 *bufp = buf;
-
-	/*
-	 * Somewhat arbitrarily, choose the 0x00FF0000-masked byte
-	 * returned by random() as having good entropy. PRNGs often
-	 * don't provide good entropy in lower bits, and the top byte
-	 * might show a pattern because of sign issues.
-	 */
-
-	while ( len-- ) {
-		*bufp++ = ( random() >> 16 ) & 0xFF;
-	}
-}

src/include/ipxe/crypto.h

@@ -151,6 +151,4 @@ extern struct digest_algorithm digest_null;
 extern struct cipher_algorithm cipher_null;
 extern struct pubkey_algorithm pubkey_null;
 
-void get_random_bytes ( void *buf, size_t len );
-
 #endif /* _IPXE_CRYPTO_H */