Commit: f4d41c5e81536839d3edddb6afeb2a537fbb3e1e - evil_int (git)

Some kinds of integer abuse (bugs and vulnerabilities) that can be found in programs.

Commit MetaInfo

• Revision: f4d41c5e81536839d3edddb6afeb2a537fbb3e1e (tree)
• Time: 2020-11-13 21:34:31
• Author: Joel Matthew Rees <joel.rees@gmai...>
• Commiter: Joel Matthew Rees

Log Message

solved the semicolong in the parameter list problem

Change Summary

• modified: evil_int.c

Incremental Difference

--- a/evil_int.c
+++ b/evil_int.c
@@ -21,21 +21,26 @@ typedef short * shortptr_t;
 typedef long * longptr_t;
 
 
-#define writeMSB1st( type, val, ptr )	\
-void write##type##MSB1st( type val; type##ptr_t ptr )	\
+/* Macros hide the meaning. Maybe C++ would work better for this. 
+** Maybe I'm trying too hard.
+*/
+
+
+#define writeMSB1st( type )	\
+void write##type##MSB1st( type value, type##ptr_t memptr )	\
 {	\
-  byteptr_t bytes = ( (byteptr_t) ptr ) + sizeof val;	\
+  byteptr_t bytes = ( (byteptr_t) memptr ) + sizeof value;	\
   for ( ;; ) 	\
   {	\
-    * --bytes = (byte_t) ( val & UCHAR_MAX );	\
-    if ( bytes <= (byteptr_t) ptr ) break;	\
-    val >>= CHAR_BIT;	\
+    * --bytes = (byte_t) ( value & UCHAR_MAX );	\
+    if ( bytes <= (byteptr_t) memptr ) break;	\
+    value >>= CHAR_BIT;	\
   }	\
 }
 
 
 #define writeLSB1st( type )	\
-void write##type##LSB1st( type value; type##ptr_t memptr )	\
+void write##type##LSB1st( type value, type##ptr_t memptr )	\
 {	\
   byteptr_t bytes = ( (byteptr_t) memptr );	\
   byteptr_t bound = bytes + sizeof value;	\
@@ -48,32 +53,36 @@ void write##type##LSB1st( type value; type##ptr_t memptr )	\
 }
 
 
-long readlongMSB1st( longptr_t memptr )
-{
-  long value = 0;
-  byteptr_t bytes = ( (byteptr_t) memptr ) + sizeof value;
-  while ( bytes >= (byteptr_t) memptr )
-  {
-    value |= * --bytes;
-    value <<= CHAR_BIT;
-  }
+#define readMSB1st( type )	\
+type read##type##MSB1st( type##ptr_t memptr )	\
+{	\
+  type value = 0;	\
+  byteptr_t bytes = ( (byteptr_t) memptr ) + sizeof value;	\
+  while ( bytes >= (byteptr_t) memptr )	\
+  {	\
+    value |= * --bytes;	\
+    value <<= CHAR_BIT;	\
+  }	\
+  return value;	\
 }
 
 
-long readlongLSB1st( longptr_t memptr )
-{
-  long value = 0;
-  byteptr_t bytes = (byteptr_t) memptr;
-  byteptr_t bound = bytes + sizeof value;
-  while ( bytes < bound )
-  {
-    value |= * bytes++;
-    value <<= CHAR_BIT;
-  }
+#define readLSB1st( type )	\
+type read##type##LSB1st( type##ptr_t memptr )	\
+{	\
+  type value = 0;	\
+  byteptr_t bytes = (byteptr_t) memptr;	\
+  byteptr_t bound = bytes + sizeof value;	\
+  while ( bytes < bound )	\
+  {	\
+    value |= * bytes++;	\
+    value <<= CHAR_BIT;	\
+  }	\
+  return value;	\
 }
 
 
-writeMSB1st( long, value, memptr )
+writeMSB1st( long )
 
 writeMSB1st( short )
 
@@ -81,6 +90,13 @@ writeLSB1st( long )
 
 writeLSB1st( short )
 
+readMSB1st( long )
+
+readMSB1st( short )
+
+readLSB1st( long )
+
+readLSB1st( short )
 
 
 int main( int argc, char *argv[] )
@@ -288,9 +304,12 @@ int main( int argc, char *argv[] )
 
   printf( "To get the full effect of this,\n"
     "be sure to compile and run on both least significant first\n"
-    "and most significant first architectures.\n"
+    "and most significant first architectures.\n\n"
     "Ask yourself, \n"
-    "on which architecture will you notice the effects more quickly?\n\n" );
+    "on which architecture will you notice the evil effects more quickly,\n"
+    "so you will know it needs to be fixed?\n\n"
+    "But most people don't have access to MSB1st hardware any more,\n"
+    "so I'll simulate both below:\n\n" );
 
 
   return EXIT_SUCCESS;