Poll clock_gettime in High_Resolution_Timestamp::poll with whatever

clock types we know about that have macros defined for them.

3 files changed, 42 insertions, 1 deletions

diff --git a/doc/log.txt b/doc/log.txt
index 696fa4ac9..d82f47157 100644
--- a/doc/log.txt
+++ b/doc/log.txt
@@ -16,6 +16,9 @@ Version 1.10.2, Not Yet Released
   replace will allow running it under Python 2.5::
      perl -pi -e 's/except (.*) as (.*):/except $1, $2:/g' configure.py
 
+* If clock_gettime is available on the system, poll all available
+  clock types in the hres_timer poll.
+
 * Add AltiVec detection for IBM POWER7 processors.
 
 * Don't set a soname on OpenBSD, as it doesn't support it (PR 158)
diff --git a/src/entropy/hres_timer/hres_timer.cpp b/src/entropy/hres_timer/hres_timer.cpp
index 7313590e5..dd1fc6f7c 100644
--- a/src/entropy/hres_timer/hres_timer.cpp
+++ b/src/entropy/hres_timer/hres_timer.cpp
@@ -1,6 +1,6 @@
 /*
 * High Resolution Timestamp Entropy Source
-* (C) 1999-2009 Jack Lloyd
+* (C) 1999-2009,2011 Jack Lloyd
 *
 * Distributed under the terms of the Botan license
 */
@@ -22,9 +22,44 @@ void High_Resolution_Timestamp::poll(Entropy_Accumulator& accum)
    {
    // If Windows, grab the Performance Counter (usually TSC or PIT)
 #if defined(BOTAN_TARGET_OS_IS_WINDOWS)
+   {
    LARGE_INTEGER tv;
    ::QueryPerformanceCounter(&tv);
    accum.add(tv.QuadPart, 0);
+   }
+#endif
+
+#if defined(BOTAN_TARGET_OS_HAS_CLOCK_GETTIME)
+
+#define CLOCK_POLL(src)                     \
+   do {                                     \
+     struct timespec ts;                    \
+     clock_gettime(src, &ts);               \
+     accum.add(&ts, sizeof(ts), 0);         \
+   } while(0)
+
+#if defined(CLOCK_REALTIME)
+   CLOCK_POLL(CLOCK_REALTIME);
+#endif
+
+#if defined(CLOCK_MONOTONIC)
+   CLOCK_POLL(CLOCK_MONOTONIC);
+#endif
+
+#if defined(CLOCK_MONOTONIC_RAW)
+   CLOCK_POLL(CLOCK_MONOTONIC_RAW);
+#endif
+
+#if defined(CLOCK_PROCESS_CPUTIME_ID)
+   CLOCK_POLL(CLOCK_PROCESS_CPUTIME_ID);
+#endif
+
+#if defined(CLOCK_THREAD_CPUTIME_ID)
+   CLOCK_POLL(CLOCK_THREAD_CPUTIME_ID);
+#endif
+
+#undef CLOCK_POLL
+
 #endif
 
 #if BOTAN_USE_GCC_INLINE_ASM
diff --git a/src/entropy/hres_timer/hres_timer.h b/src/entropy/hres_timer/hres_timer.h
index c693b8d4e..8b95c8308 100644
--- a/src/entropy/hres_timer/hres_timer.h
+++ b/src/entropy/hres_timer/hres_timer.h
@@ -14,6 +14,9 @@ namespace Botan {
 
 /**
 * Entropy source using high resolution timers
+*
+* @note Any results from timers are marked as not contributing entropy
+* to the poll, as a local attacker could observe them directly.
 */
 class High_Resolution_Timestamp : public EntropySource
    {