Add randombytes submodule

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "randombytes"]
+	path = randombytes
+	url = https://github.com/dsprenkels/randombytes.git

randombytes.c

@@ -1,20 +0,0 @@
-#include "randombytes.h"
-#include <assert.h>
-#include <string.h>
-
-#ifdef __linux__
-# define _GNU_SOURCE
-# include <sys/syscall.h>
-#endif
-
-
-void randombytes(void *buf, const size_t n)
-{
-#ifdef __linux__
-	int tmp = syscall(SYS_getrandom, buf, n, 0);
-	assert(tmp == n); /* Failure indicates a bug in the code */
-#else
-# warning "randombytes(...) is not supported on this platform. Using INSECURE dummy version."
-	memset(buf, 42, n);
-#endif /* __linux__ */
-}

randombytes.c

@@ -0,0 +1 @@
+randombytes/randombytes.c

randombytes.h

@@ -1,14 +0,0 @@
-#ifndef sss_RANDOMBYTES_H
-#define sss_RANDOMBYTES_H
-
-#include <sys/syscall.h>
-#include <unistd.h>
-
-
-/*
- * Write `n` bytes of high quality random bytes to `buf`
- */
-void randombytes(void *buf, size_t n);
-
-
-#endif /* sss_RANDOMBYTES_H */

randombytes.h

@@ -0,0 +1 @@
+randombytes/randombytes.h