Make temporary buffer a SecBlock for zeroization

1 files changed, 18 insertions, 17 deletions

diff --git a/darn.cpp b/darn.cpp
index 87640a25..f3947403 100644
--- a/darn.cpp
+++ b/darn.cpp
@@ -8,11 +8,11 @@
 #include "cpu.h"

 

 // At the moment only GCC 7.0 (and above) seems to support __builtin_darn()

-// and __builtin_darn_32(). Clang 7.0 does not provide them. XLC is unknown,

-// but there are no hits when searching IBM's site. To cover more platforms

-// we provide GCC inline assembly like we do with RDRAND and RDSEED.

-// Platforms that don't support GCC inline assembly or the builtin will fail

-// the compile.

+// and __builtin_darn_32(). Clang 7.0 does not provide them, but it does

+// support assembly instructions. XLC is unknown, but there are no hits when

+// searching IBM's site. To cover more platforms we provide GCC inline

+// assembly like we do with RDRAND and RDSEED. Platforms that don't support

+// GCC inline assembly or the builtin will fail the compile.

 

 // Inline assembler available in GCC 3.2 or above. For practical

 // purposes we check for GCC 4.0 or above. GCC imposters claim

@@ -121,6 +121,9 @@ DARN::DARN()
 {

     if (!HasDARN())

         throw DARN_Err("HasDARN");

+

+    // Scratch buffer in case user buffers are unaligned.

+    m_temp.New(8);

 }

 

 void DARN::GenerateBlock(byte *output, size_t size)

@@ -131,13 +134,12 @@ void DARN::GenerateBlock(byte *output, size_t size)
 

 #if (CRYPTOPP_BOOL_PPC64)

 

-    word64 val;

+    // Check alignment

     i = reinterpret_cast<uintptr_t>(output) & 0x7;

-

     if (i != 0)

     {

-        DARN64(&val);

-        std::memcpy(output, &val, i);

+        DARN64(m_temp);

+        std::memcpy(output, m_temp, i);

 

         output += i;

         size -= i;

@@ -152,19 +154,18 @@ void DARN::GenerateBlock(byte *output, size_t size)
 

     if (size)

     {

-        DARN64(&val);

-        std::memcpy(output, &val, size);

+        DARN64(m_temp);

+        std::memcpy(output, m_temp, size);

     }

 

 #elif (CRYPTOPP_BOOL_PPC32)

 

-    word32 val;

+    // Check alignment

     i = reinterpret_cast<uintptr_t>(output) & 0x3;

-

     if (i != 0)

     {

-        DARN32(&val);

-        std::memcpy(output, &val, i);

+        DARN32(m_temp);

+        std::memcpy(output, m_temp, i);

 

         output += i;

         size -= i;

@@ -178,8 +179,8 @@ void DARN::GenerateBlock(byte *output, size_t size)
 

     if (size)

     {

-        DARN32(&val);

-        std::memcpy(output, &val, size);

+        DARN32(m_temp);

+        std::memcpy(output, m_temp, size);

     }

 

 #else