add a stripping tool and a random key experiment

CMakeLists.txt

@@ -2,10 +2,10 @@ cmake_minimum_required(VERSION 3.10)
 project(checkm8_tool)
 enable_language(C ASM)
 
-include(${CMAKE_ROOT}/Modules/ExternalProject.cmake)
-
-include_directories(c8_remote/include)
 include_directories(include)
 
-add_subdirectory(c8_remote/lib)
+# set up checkm8_remote
 add_subdirectory(c8_remote)
+
+# targets for external tools
+add_executable(tool_corr_strip  tools/correlation/strip/main.c)

c8_remote/CMakeLists.txt

@@ -5,6 +5,7 @@ set(CMAKE_C_STANDARD 99)
 set(CMAKE_C_FLAGS "-g -Wall")
 
 include_directories(include)
+add_subdirectory(lib)
 
 add_executable(checkm8_remote main.c src/usb_helpers.c src/exploit.c src/payload.c src/command.c)
 target_link_libraries(checkm8_remote usb-1.0 pthread udev m)

c8_remote/main.c

@@ -4,6 +4,7 @@
 #include <string.h>
 #include <stdlib.h>
 #include <math.h>
+#include <time.h>
 
 #include "dev/types.h"
 #include "util/experiments.h"
@@ -106,12 +107,26 @@ void run_corr_exp(struct pwned_device *dev, char *fname)
     unsigned char key[16];
     unsigned char key_sched[176];
 
+    sprintf(fname, "KEY");
+    outfile = fopen(fname, "w");
+    if(outfile == NULL)
+    {
+        printf("failed to open key file\n");
+        return;
+    }
+
+    srand(time(NULL));
     for(i = 0; i < 16; i++)
     {
         msg[i] = 0;
-        key[i] = 0x0;
+        key[i] = random();
+        fprintf(outfile, "%02x", key[i]);
     }
 
+    fprintf(outfile, "\n");
+    fflush(outfile);
+    fclose(outfile);
+
     expand_key(key, key_sched, 11, c);
 
     addr_async_buf = setup_corr_exp(dev, key);

tools/correlation/strip/main.c

@@ -0,0 +1,83 @@
+#include <stdio.h>
+#include <string.h>
+#include <libgen.h>
+
+struct entry
+{
+    unsigned char msg[16];
+    unsigned char pad0;
+
+    unsigned char timing;
+    unsigned char pad1[2];
+} __attribute__ ((packed));
+
+int main(int argc, char *argv[])
+{
+    FILE *infile, *timingfile, *msgfile;
+    char fname[128], c1[128], c2[128], *path, *name;
+
+    strcpy(c1, argv[1]);
+    strcpy(c2, argv[1]);
+
+    int count = 0;
+    unsigned long read;
+    struct entry e;
+
+    if(argc != 2)
+    {
+        printf("usage: strip [fname]\n");
+        return -1;
+    }
+
+    path = dirname(c1);
+    name = basename(c2);
+
+    infile = fopen(argv[1], "rb");
+    if(infile == NULL)
+    {
+        printf("failed to open file %s\n", argv[1]);
+        return -1;
+    }
+
+    sprintf(fname, "%s/timing_%s", path, name);
+    timingfile = fopen(fname, "wb");
+    if(timingfile == NULL)
+    {
+        printf("failed to open timing output\n");
+        return -1;
+    }
+
+    sprintf(fname, "%s/msg_%s", path, name);
+    msgfile = fopen(fname, "wb");
+    if(msgfile == NULL)
+    {
+        printf("failed to open message output\n");
+        return -1;
+    }
+
+    while(!(ferror(infile) || feof(infile)))
+    {
+        read = fread(&e, sizeof(struct entry), 1, infile);
+        if(read != 1)
+            break;
+
+        fwrite(&e.timing, 1, 1, timingfile);
+        if(count % (1024 * 256) == 0)
+        {
+            fwrite(&e.msg, 16, 1, msgfile);
+            printf("stripped %i entries\n", count);
+        }
+
+        count++;
+    }
+
+    printf("strip finished with ferror %i feof %i\n", ferror(infile), feof(infile));
+
+    fflush(timingfile);
+    fflush(msgfile);
+
+    fclose(infile);
+    fclose(timingfile);
+    fclose(msgfile);
+    return 0;
+}