ParDiff

ParDiff is the implementation for our paper published in OOPSLA 2024:

ParDiff: Practical Static Differential Analysis of Network Protocol Parsers
Mingwei Zheng, Qingkai Shi, Xuwei Liu, Xiangzhe Xu, Le Yu, Congyu Liu, Guannan Wei, Xiangyu Zhang
ACM SIGPLAN International Conference on Object-Oriented Programming Systems, Languages, and Applications (OOPSLA '24) 

It aims to find logical bugs in network protocol implementations using static differential analysis.

Input

To use ParDiff, please prepare bitcode for two implementations under comparison: target1.bc and target2.bc. Here we provide an example under pardiff/tests.

To create your own test cases, please follow the steps below to get bitcode as input:

• The source code must be implemented in C and can be compiled using clang-12 and wllvm.
• Annotate the entry parsing function in the source code using the interfaces we provide below:

  void * pardiff_make_object(unsigned size);
  // This interface works as the C lib interface, malloc(), which allocates space in memory with a given size. 
  void * pardiff_make_message();
  // This interface creates a buffer of the networking data.
  unsigned pardiff_make_message_length();
  // This interface indicates the length of the input networking data

Here is an example how we do annotations on the FRR/babeld parser:

#include <stdint.h>
#include <stdio.h>
#include "config.h"
#include <stdlib.h>
#include "message.h"

void *pardiff_make_object(uint64_t size);

void *pardiff_make_message(void);

int pardiff_make_message_length(void);

int pardiff_main_message(){
    unsigned char *from = pardiff_make_object(sizeof(char));
    struct interface *ifp = pardiff_make_object(sizeof(struct interface));
    unsigned char *packet = pardiff_make_message();
    int len = pardiff_make_message_length();
    parse_packet(from, ifp,packet, len); 
    return 0; 
}

• After finishing the annotation, use Clang-12 and WLLVM to compile the software project and get a bitcode. See WLLVM for more details on how to get a bitcode.

Build

Compiler

• gcc-11.2.0

Dependency:

• llvm-12.0.1
• z3-4.8.12 better use our copy: z3 need to compile and install using cmake

$  mkdir  build
$  cd  build
$  cmake  ..
$  make -j8

Run with our example

./bin/pardiff ../tests/target1.bc ../tests/target2.bc -pardiff-entry=pardiff_main_message > diff.txt 2>&1