diff --git a/common/include/villas/cpuset.hpp b/common/include/villas/cpuset.hpp
index 9d0597170..db190b239 100644
--- a/common/include/villas/cpuset.hpp
+++ b/common/include/villas/cpuset.hpp
@@ -193,7 +193,7 @@ public:
 	}
 };
 
-} // namespace utils
-} // namespace villas
+} /* namespace utils */
+} /* namespace villas */
 
 #endif
diff --git a/common/include/villas/dsp/exponential_window.hpp b/common/include/villas/dsp/exponential_window.hpp
index 8fea57d4f..82f421457 100644
--- a/common/include/villas/dsp/exponential_window.hpp
+++ b/common/include/villas/dsp/exponential_window.hpp
@@ -49,5 +49,5 @@ public:
 	}
 };
 
-} // namespace dsp
-} // namespace villas
+} /* namespace dsp */
+} /* namespace villas */
diff --git a/common/include/villas/dsp/moving_average_window.hpp b/common/include/villas/dsp/moving_average_window.hpp
index 64f6e33ef..cc72559ea 100644
--- a/common/include/villas/dsp/moving_average_window.hpp
+++ b/common/include/villas/dsp/moving_average_window.hpp
@@ -52,5 +52,5 @@ public:
 	}
 };
 
-} // namespace dsp
-} // namespace villas
+} /* namespace dsp */
+} /* namespace villas */
diff --git a/common/include/villas/dsp/pid.hpp b/common/include/villas/dsp/pid.hpp
index 8adc3bf43..df9a89054 100644
--- a/common/include/villas/dsp/pid.hpp
+++ b/common/include/villas/dsp/pid.hpp
@@ -53,5 +53,5 @@ public:
         double calculate(double setpoint, double pv);
 };
 
-} // namespace dsp
-} // namespace villas
+} /* namespace dsp */
+} /* namespace villas */
diff --git a/common/include/villas/dsp/window.hpp b/common/include/villas/dsp/window.hpp
index ed7669be2..4be9f9db3 100644
--- a/common/include/villas/dsp/window.hpp
+++ b/common/include/villas/dsp/window.hpp
@@ -77,5 +77,5 @@ public:
 	}
 };
 
-} // namespace dsp
-} // namespace villas
+} /* namespace dsp */
+} /* namespace villas */
diff --git a/common/include/villas/exceptions.hpp b/common/include/villas/exceptions.hpp
index ca3c0c929..4bdba92b0 100644
--- a/common/include/villas/exceptions.hpp
+++ b/common/include/villas/exceptions.hpp
@@ -144,4 +144,4 @@ public:
 	}
 };
 
-} // namespace villas
+} /* namespace villas */
diff --git a/common/include/villas/graph/directed.hpp b/common/include/villas/graph/directed.hpp
index b414c3be5..a4f63448b 100644
--- a/common/include/villas/graph/directed.hpp
+++ b/common/include/villas/graph/directed.hpp
@@ -294,4 +294,4 @@ protected:
 };
 
 } // namespacae graph
-} // namespace villas
+} /* namespace villas */
diff --git a/common/include/villas/graph/edge.hpp b/common/include/villas/graph/edge.hpp
index 1856b72a2..18b5441e9 100644
--- a/common/include/villas/graph/edge.hpp
+++ b/common/include/villas/graph/edge.hpp
@@ -54,4 +54,4 @@ private:
 };
 
 } // namespacae graph
-} // namespace villas
+} /* namespace villas */
diff --git a/common/include/villas/graph/vertex.hpp b/common/include/villas/graph/vertex.hpp
index bece20741..b4c7816ad 100644
--- a/common/include/villas/graph/vertex.hpp
+++ b/common/include/villas/graph/vertex.hpp
@@ -52,4 +52,4 @@ private:
 };
 
 } // namespacae graph
-} // namespace villas
+} /* namespace villas */
diff --git a/common/include/villas/json_buffer.hpp b/common/include/villas/json_buffer.hpp
index 154a11acf..da109a17f 100644
--- a/common/include/villas/json_buffer.hpp
+++ b/common/include/villas/json_buffer.hpp
@@ -55,4 +55,4 @@ public:
 	json_t * decode();
 };
 
-} // namespace villas
+} /* namespace villas */
diff --git a/common/include/villas/kernel/kernel.hpp b/common/include/villas/kernel/kernel.hpp
index 597a49100..da954d615 100644
--- a/common/include/villas/kernel/kernel.hpp
+++ b/common/include/villas/kernel/kernel.hpp
@@ -31,5 +31,5 @@ namespace kernel {
 /** Get the version of the kernel. */
 utils::Version getVersion();
 
-} // namespace villas
-} // namespace kernel
+} /* namespace villas */
+} /* namespace kernel */
diff --git a/common/include/villas/kernel/rt.hpp b/common/include/villas/kernel/rt.hpp
index 506d69573..8c68ece40 100644
--- a/common/include/villas/kernel/rt.hpp
+++ b/common/include/villas/kernel/rt.hpp
@@ -47,8 +47,8 @@ void setPriority(int priority);
  */
 bool isPreemptible();
 
-} // namespace villas
-} // namespace kernel
-} // namespace rt
+} /* namespace villas */
+} /* namespace kernel */
+} /* namespace rt */
 
 /** @} */
diff --git a/common/include/villas/kernel/vfio.hpp b/common/include/villas/kernel/vfio.hpp
index 0079ee8f3..dcd196292 100644
--- a/common/include/villas/kernel/vfio.hpp
+++ b/common/include/villas/kernel/vfio.hpp
@@ -162,4 +162,4 @@ private:
 
 /** @} */
 
-} // namespace villas
+} /* namespace villas */
diff --git a/common/include/villas/log.hpp b/common/include/villas/log.hpp
index aca4b8e4d..6baa70ff6 100644
--- a/common/include/villas/log.hpp
+++ b/common/include/villas/log.hpp
@@ -81,4 +81,4 @@ public:
 	std::string getLevelName() const;
 };
 
-} // namespace villas
+} /* namespace villas */
diff --git a/common/include/villas/log_opal_sink.hpp b/common/include/villas/log_opal_sink.hpp
index 90c7c825c..5d5d73949 100644
--- a/common/include/villas/log_opal_sink.hpp
+++ b/common/include/villas/log_opal_sink.hpp
@@ -61,5 +61,5 @@ using OpalSink_mt = OpalSink<std::mutex>;
 using OpalSink_st = OpalSink<spdlog::details::null_mutex>;
 
 
-} // namespace node
-} // namespace villas
+} /* namespace node */
+} /* namespace villas */
diff --git a/common/include/villas/memory.hpp b/common/include/villas/memory.hpp
index 410355eea..3c6f7ccc2 100644
--- a/common/include/villas/memory.hpp
+++ b/common/include/villas/memory.hpp
@@ -329,4 +329,4 @@ private:
 	static std::map<int, std::unique_ptr<HostDmaRamAllocator>> allocators;
 };
 
-} // namespace villas
+} /* namespace villas */
diff --git a/common/include/villas/memory_manager.hpp b/common/include/villas/memory_manager.hpp
index 987daf899..5dcc11186 100644
--- a/common/include/villas/memory_manager.hpp
+++ b/common/include/villas/memory_manager.hpp
@@ -271,4 +271,4 @@ private:
 	static MemoryManager* instance;
 };
 
-} // namespace villas
+} /* namespace villas */
diff --git a/common/include/villas/plugin.hpp b/common/include/villas/plugin.hpp
index 97d491f47..e57067a0b 100644
--- a/common/include/villas/plugin.hpp
+++ b/common/include/villas/plugin.hpp
@@ -135,5 +135,5 @@ protected:
 	}
 };
 
-} // namespace plugin
-} // namespace villas
+} /* namespace plugin */
+} /* namespace villas */
diff --git a/common/include/villas/terminal.hpp b/common/include/villas/terminal.hpp
index 546cccc77..ffb2b49c6 100644
--- a/common/include/villas/terminal.hpp
+++ b/common/include/villas/terminal.hpp
@@ -62,4 +62,4 @@ public:
 	}
 };
 
-} // namespace villas
+} /* namespace villas */
diff --git a/common/include/villas/tool.hpp b/common/include/villas/tool.hpp
index 266d7ba13..1f02a8534 100644
--- a/common/include/villas/tool.hpp
+++ b/common/include/villas/tool.hpp
@@ -68,4 +68,4 @@ public:
 	int run();
 };
 
-} // namespace villas
+} /* namespace villas */
diff --git a/common/include/villas/utils.hpp b/common/include/villas/utils.hpp
index 847116e94..cd7288f2e 100644
--- a/common/include/villas/utils.hpp
+++ b/common/include/villas/utils.hpp
@@ -28,14 +28,13 @@
 #include <vector>
 
 #include <signal.h>
-
-
 #include <stdlib.h>
 #include <stdint.h>
 #include <sched.h>
 #include <assert.h>
 #include <sys/types.h>
-#include <signal.h>
+
+#include <openssl/sha.h>
 
 #include <villas/config.h>
 #include <villas/log.h>
@@ -202,7 +201,23 @@ pid_t spawn(const char *name, char *const argv[]);
 /** Determines the string length as printed on the screen (ignores escable sequences). */
 size_t strlenp(const char *str);
 
-} // namespace utils
-} // namespace villas
+/** Calculate SHA1 hash of complete file \p f and place it into \p sha1.
+ *
+ * @param sha1[out] Must be SHA_DIGEST_LENGTH (20) in size.
+ * @retval 0 Everything was okay.
+ */
+int sha1sum(FILE *f, unsigned char *sha1);
+
+namespace base64 {
+
+std::string encode(const std::string &str);
+std::string encode(const unsigned char *input, size_t len);
+
+std::string decode(const std::string &str);
+std::string decode(unsigned char *input, size_t len);
+
+} /* namespace base64 */
+} /* namespace utils */
+} /* namespace villas */
 
 using namespace villas::utils;
diff --git a/common/include/villas/version.hpp b/common/include/villas/version.hpp
index f65ce2bb0..0b14fb3be 100644
--- a/common/include/villas/version.hpp
+++ b/common/include/villas/version.hpp
@@ -49,5 +49,5 @@ public:
 	inline bool operator>=(const Version& rhs) { return cmp(*this, rhs) >= 0; }
 };
 
-} // namespace villas
-} // namespace utils
+} /* namespace villas */
+} /* namespace utils */