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-rw-r--r--src/build-data/buildh.in3
-rw-r--r--src/lib/entropy/rdrand/rdrand.cpp39
-rw-r--r--src/lib/entropy/rdrand/rdrand.h4
-rw-r--r--src/lib/entropy/rdseed/rdseed.cpp29
-rw-r--r--src/lib/entropy/rdseed/rdseed.h4
5 files changed, 42 insertions, 37 deletions
diff --git a/src/build-data/buildh.in b/src/build-data/buildh.in
index 84756536d..d709c27af 100644
--- a/src/build-data/buildh.in
+++ b/src/build-data/buildh.in
@@ -180,6 +180,9 @@ Each poll generates 32 bit entropy
*/
#define BOTAN_ENTROPY_INTEL_RNG_POLLS 32
+// According to Intel RdRand is guaranteed to generate a random number within 10 retries on a working CPU
+#define BOTAN_ENTROPY_RDRAND_RETRIES 10
+
/*
* RdSeed is not guaranteed to generate a random number within a specific number of retries
* Define the number of retries here
diff --git a/src/lib/entropy/rdrand/rdrand.cpp b/src/lib/entropy/rdrand/rdrand.cpp
index 36eaebee3..ef8c5882d 100644
--- a/src/lib/entropy/rdrand/rdrand.cpp
+++ b/src/lib/entropy/rdrand/rdrand.cpp
@@ -1,26 +1,26 @@
/*
* Entropy Source Using Intel's rdrand instruction
* (C) 2012,2015 Jack Lloyd
+* (C) 2015 Daniel Neus
*
* Botan is released under the Simplified BSD License (see license.txt)
*/
#include <botan/internal/rdrand.h>
#include <botan/cpuid.h>
-#include <botan/exceptn.h>
#include <botan/build.h>
#if !defined(BOTAN_USE_GCC_INLINE_ASM)
- #include <immintrin.h>
+#include <immintrin.h>
#endif
-// RDRAND is guaranteed to generate a random number within 10 retries on a working CPU
-#define INTEL_RDRAND_RETRIES 10
-
namespace Botan {
-uint32_t Intel_Rdrand::get32BitRandom() {
- for ( size_t i = 0; i != INTEL_RDRAND_RETRIES; ++i )
+namespace {
+
+/// @returns 0 if RdRand failed after @param max_retries otherwise the 32 bit random number generated by RdRand
+uint32_t get_32bit_random(const uint32_t max_retries) {
+ for(size_t i = 0; i != max_retries; ++i)
{
uint32_t r = 0;
@@ -28,28 +28,31 @@ uint32_t Intel_Rdrand::get32BitRandom() {
int cf = 0;
// Encoding of rdrand %eax
- asm( ".byte 0x0F, 0xC7, 0xF0; adcl $0,%1" :
- "=a" ( r ), "=r" ( cf ) : "0" ( r ), "1" ( cf ) : "cc" );
+ asm(".byte 0x0F, 0xC7, 0xF0; adcl $0,%1" :
+ "=a" (r), "=r" (cf) : "0" (r), "1" (cf) : "cc");
#else
- int cf = _rdrand32_step( &r );
+ int cf = _rdrand32_step(&r);
#endif
- if ( 1 == cf )
+ if(1 == cf)
{
return r;
}
}
-
- throw Internal_Error( "RdRand failed after " + std::to_string( INTEL_RDRAND_RETRIES ) + " retries" );
+ return 0;
}
+}
-void Intel_Rdrand::poll( Entropy_Accumulator& accum ) {
- if ( !CPUID::has_rdrand() )
+void Intel_Rdrand::poll(Entropy_Accumulator& accum) {
+ if(!CPUID::has_rdrand())
return;
- for ( size_t i = 0; i != BOTAN_ENTROPY_INTEL_RNG_POLLS; ++i )
+ for(size_t i = 0; i != BOTAN_ENTROPY_INTEL_RNG_POLLS; ++i)
{
- uint32_t random = get32BitRandom();
- accum.add( random, BOTAN_ENTROPY_ESTIMATE_HARDWARE_RNG );
+ uint32_t random = get_32bit_random(BOTAN_ENTROPY_RDRAND_RETRIES);
+ if(random)
+ {
+ accum.add(random, BOTAN_ENTROPY_ESTIMATE_HARDWARE_RNG);
+ }
}
}
diff --git a/src/lib/entropy/rdrand/rdrand.h b/src/lib/entropy/rdrand/rdrand.h
index 5ace28382..1fa928641 100644
--- a/src/lib/entropy/rdrand/rdrand.h
+++ b/src/lib/entropy/rdrand/rdrand.h
@@ -20,9 +20,7 @@ class Intel_Rdrand : public Entropy_Source
{
public:
std::string name() const override { return "rdrand"; }
- void poll( Entropy_Accumulator& accum ) override;
- private:
- static uint32_t get32BitRandom();
+ void poll(Entropy_Accumulator& accum) override;
};
}
diff --git a/src/lib/entropy/rdseed/rdseed.cpp b/src/lib/entropy/rdseed/rdseed.cpp
index b995ab5d4..adca605f6 100644
--- a/src/lib/entropy/rdseed/rdseed.cpp
+++ b/src/lib/entropy/rdseed/rdseed.cpp
@@ -10,14 +10,16 @@
#include <botan/build.h>
#if !defined(BOTAN_USE_GCC_INLINE_ASM)
- #include <immintrin.h>
+#include <immintrin.h>
#endif
namespace Botan {
+namespace {
+
/// @returns 0 if RdSeed failed after @param max_retries otherwise the 32 bit random number generated by RdSeed
-uint32_t Intel_Rdseed::get32BitRandom( const uint32_t max_retries ) {
- for ( size_t i = 0; i != max_retries; ++i )
+uint32_t get_32bit_random(const uint32_t max_retries) {
+ for(size_t i = 0; i != max_retries; ++i)
{
uint32_t r = 0;
@@ -25,29 +27,30 @@ uint32_t Intel_Rdseed::get32BitRandom( const uint32_t max_retries ) {
int cf = 0;
// Encoding of rdseed %eax
- asm( ".byte 0x0F, 0xC7, 0xF8; adcl $0,%1" :
- "=a" ( r ), "=r" ( cf ) : "0" ( r ), "1" ( cf ) : "cc" );
+ asm(".byte 0x0F, 0xC7, 0xF8; adcl $0,%1" :
+ "=a" (r), "=r" (cf) : "0" (r), "1" (cf) : "cc");
#else
- int cf = _rdseed32_step( &r );
+ int cf = _rdseed32_step(&r);
#endif
- if ( 1 == cf )
+ if(1 == cf)
{
return r;
}
}
return 0;
}
+}
-void Intel_Rdseed::poll( Entropy_Accumulator& accum ) {
- if ( !CPUID::has_rdseed() )
+void Intel_Rdseed::poll(Entropy_Accumulator& accum) {
+ if(!CPUID::has_rdseed())
return;
- for ( size_t i = 0; i != BOTAN_ENTROPY_INTEL_RNG_POLLS; ++i )
+ for(size_t i = 0; i != BOTAN_ENTROPY_INTEL_RNG_POLLS; ++i)
{
- uint32_t random = get32BitRandom( BOTAN_ENTROPY_RDSEED_RETRIES );
- if ( random )
+ uint32_t random = get_32bit_random(BOTAN_ENTROPY_RDSEED_RETRIES);
+ if(random)
{
- accum.add( random, BOTAN_ENTROPY_ESTIMATE_HARDWARE_RNG );
+ accum.add(random, BOTAN_ENTROPY_ESTIMATE_HARDWARE_RNG);
}
}
}
diff --git a/src/lib/entropy/rdseed/rdseed.h b/src/lib/entropy/rdseed/rdseed.h
index a6f92709a..0f39250a1 100644
--- a/src/lib/entropy/rdseed/rdseed.h
+++ b/src/lib/entropy/rdseed/rdseed.h
@@ -20,9 +20,7 @@ class Intel_Rdseed : public Entropy_Source
{
public:
std::string name() const override { return "rdseed"; }
- void poll( Entropy_Accumulator& accum ) override;
- private:
- static uint32_t get32BitRandom( uint32_t max_retries );
+ void poll(Entropy_Accumulator& accum) override;
};
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-23 21:05:27 +0000