Last minute es_ftw optimizations / logic changes. Performance of seeding

was too slow, it was noticably slowing down AutoSeeded_RNG. Reduce the
amount of output gathered to 32 times the size of the output buffer,
and instead of using Buffered_EntropySource, just xor the read file
data directly into the output buffer. Read up to 4096 bytes per file, but
only count the first 128 towards the total goal (/proc/config.gz being
a major culprit - large, random looking, and entirely or almost static).

1 files changed, 6 insertions, 7 deletions

diff --git a/src/entropy/proc_walk/es_ftw.h b/src/entropy/proc_walk/es_ftw.h
index a0d480aae..5b127943f 100644
--- a/src/entropy/proc_walk/es_ftw.h
+++ b/src/entropy/proc_walk/es_ftw.h
@@ -6,18 +6,21 @@
 #ifndef BOTAN_ENTROPY_SRC_FTW_H__
 #define BOTAN_ENTROPY_SRC_FTW_H__
 
-#include <botan/buf_es.h>
+#include <botan/entropy_src.h>
 
 namespace Botan {
 
 /*************************************************
 * File Tree Walking Entropy Source               *
 *************************************************/
-class BOTAN_DLL FTW_EntropySource : public Buffered_EntropySource
+class BOTAN_DLL FTW_EntropySource : public EntropySource
    {
    public:
       std::string name() const { return "Proc Walker"; }
 
+      u32bit slow_poll(byte buf[], u32bit len);
+      u32bit fast_poll(byte buf[], u32bit len);
+
       FTW_EntropySource(const std::string& root_dir);
       ~FTW_EntropySource();
 
@@ -28,12 +31,8 @@ class BOTAN_DLL FTW_EntropySource : public Buffered_EntropySource
             virtual ~File_Descriptor_Source() {}
          };
    private:
-      void do_fast_poll();
-      void do_slow_poll();
-
-      void poll(u32bit max_read);
 
-      const std::string path;
+      std::string path;
       File_Descriptor_Source* dir;
    };