rump: Add 'get_random_backend' function

A rump server may now implement its own random number generator, the default
impelementation will not generate random number.

Issue #1409

repos/dde_rump/include/util/random.h

@@ -0,0 +1,21 @@
+/**
+ * \brief  Overwritable backend-random methods
+ * \author Sebastian Sumpf
+ * \date   2015-02-13
+ */
+
+/*
+ * Copyright (C) 2015 Genode Labs GmbH
+ *
+ * This file is part of the Genode OS framework, which is distributed
+ * under the terms of the GNU General Public License version 2.
+ */
+
+#ifndef _INCLUDE__UTIL__RANDOM_H_
+#define _INCLUDE__UTIL__RANDOM_H_
+
+#include <base/stdint.h>
+
+int rumpuser_getrandom_backend(void *buf, Genode::size_t buflen, int flags, Genode::size_t *retp);
+
+#endif /* _INCLUDE__UTIL__RANDOM_H_ */

repos/dde_rump/lib/mk/rump_base.inc

@@ -12,11 +12,6 @@ RMAKE       = $(RUMP_TOOLS)/rumpmake
 #
 VERBOSE_LEVEL ?= 0
 
-#
-# Libraries
-#
-LIBS += jitterentropy
-
 #
 # Sources
 #

repos/dde_rump/src/lib/rump/hypercall.cc

@@ -19,14 +19,9 @@
 #include <base/sleep.h>
 #include <os/timed_semaphore.h>
 #include <util/allocator_fap.h>
+#include <util/random.h>
 #include <util/string.h>
 
-extern "C" {
-	namespace Jitter {
-		#include <jitterentropy.h>
-	}
-}
-
 extern "C" void wait_for_continue();
 enum { SUPPORTED_RUMP_VERSION = 17 };
 
@@ -36,38 +31,6 @@ static bool verbose = false;
 struct rumpuser_hyperup _rump_upcalls;
 
 
-/***********************************
- ** Jitter entropy for randomness **
- ***********************************/
-
-struct Entropy
-{
-	struct Jitter::rand_data *ec_stir;
-
-	Entropy()
-	{
-		Jitter::jent_entropy_init();
-		ec_stir = Jitter::jent_entropy_collector_alloc(0, 0);
-	}
-
-	static Entropy *e()
-	{
-		static Entropy _e;
-		return &_e;
-	}
-
-	size_t read(char *buf, size_t len)
-	{
-		int err;
-		if ((err = Jitter::jent_read_entropy(ec_stir, buf, len) < 0)) {
-			PERR("Failed to read entropy: %d", err);
-			return 0;
-		}
-
-		return len;
-	}
-};
-
 /********************
  ** Initialization **
  ********************/
@@ -90,9 +53,6 @@ int rumpuser_init(int version, const struct rumpuser_hyperup *hyp)
 	 */
 	Genode::Timeout_thread::alarm_timer();
 
-	/* initialize jitter entropy */
-	Entropy::e();
-
 	return 0;
 }
 
@@ -336,8 +296,7 @@ int rumpuser_clock_sleep(int enum_rumpclock, int64_t sec, long nsec)
 
 int rumpuser_getrandom(void *buf, size_t buflen, int flags, size_t *retp)
 {
-	*retp = Entropy::e()->read((char *)buf, buflen);
+	return rumpuser_getrandom_backend(buf, buflen, flags, retp);
-	return 0;
 }
 
 

repos/dde_rump/src/lib/rump/misc.cc

@@ -15,6 +15,15 @@
 #include <util/string.h>
 
 
+/*
+ * On some platforms (namely ARM) we end-up pulling in string.h prototypes
+ */
+extern "C" void *memcpy(void *d, void *s, Genode::size_t n)
+{
+	return Genode::memcpy(d, s, n);
+}
+
+
 extern "C" void *memset(void *s, int c, Genode::size_t n)
 {
 	return Genode::memset(s, c, n);

repos/dde_rump/src/server/rump_cgd/random.cc

@@ -0,0 +1,64 @@
+/**
+ * \brief  Add random support for CGD
+ * \author Sebastian Sumpf
+ * \date   2015-02-13
+ */
+
+/*
+ * Copyright (C) 2015 Genode Labs GmbH
+ *
+ * This file is part of the Genode OS framework, which is distributed
+ * under the terms of the GNU General Public License version 2.
+ */
+
+#include <base/printf.h>
+#include <util/random.h>
+
+extern "C" {
+	namespace Jitter {
+		#include <jitterentropy.h>
+	}
+}
+
+typedef Genode::size_t size_t;
+
+
+/***********************************
+ ** Jitter entropy for randomness **
+ ***********************************/
+
+struct Entropy
+{
+	struct Jitter::rand_data *ec_stir;
+
+	Entropy()
+	{
+		Jitter::jent_entropy_init();
+		ec_stir = Jitter::jent_entropy_collector_alloc(0, 0);
+	}
+
+	static Entropy *e()
+	{
+		static Entropy _e;
+		return &_e;
+	}
+
+	size_t read(char *buf, size_t len)
+	{
+		int err;
+		if ((err = Jitter::jent_read_entropy(ec_stir, buf, len) < 0)) {
+			PERR("Failed to read entropy: %d", err);
+			return 0;
+		}
+
+		return len;
+	}
+};
+
+
+int rumpuser_getrandom_backend(void *buf, size_t buflen, int flags, size_t *retp)
+{
+	*retp = Entropy::e()->read((char *)buf, buflen);
+	*retp = buflen;
+	return 0;
+}

repos/dde_rump/src/server/rump_cgd/target.mk

@@ -1,3 +1,4 @@
 TARGET   = rump_cgd
-SRC_CC   = cgd.cc main.cc
+
-LIBS     = rump rump_cgd server startup
+SRC_CC   = cgd.cc main.cc random.cc
+LIBS     = rump rump_cgd server startup jitterentropy

repos/dde_rump/src/server/rump_fs/random.cc

@@ -0,0 +1,21 @@
+/**
+ * \brief  Dummy random support
+ * \author Sebastian Sumpf
+ * \date   2015-02-16
+ */
+
+/*
+ * Copyright (C) 2015 Genode Labs GmbH
+ *
+ * This file is part of the Genode OS framework, which is distributed
+ * under the terms of the GNU General Public License version 2.
+ */
+
+#include <util/random.h>
+
+
+int rumpuser_getrandom_backend(void *buf, Genode::size_t buflen, int flags, Genode::size_t *retp)
+{
+	*retp = buflen;
+	return 0;
+}

repos/dde_rump/src/server/rump_fs/target.mk

@@ -1,5 +1,5 @@
 TARGET   = rump_fs
-SRC_CC   = main.cc file_system.cc
+SRC_CC   = main.cc file_system.cc random.cc
 LIBS     = rump rump_fs server startup