testing/test-cases/amfi-interpose.dtest/main.c

   1 // BOOT_ARGS: dyld_flags=2
   2
   3 // BUILD:  $CC interposer.c -dynamiclib -o $BUILD_DIR/libmyalloc.dylib -install_name $RUN_DIR/libmyalloc.dylib
   4 // BUILD:  $CC main.c $BUILD_DIR/libmyalloc.dylib  -o $BUILD_DIR/amfi-interpose.exe
   5 // BUILD:  $DYLD_ENV_VARS_ENABLE $BUILD_DIR/amfi-interpose.exe
   6
   7 // RUN:  DYLD_AMFI_FAKE=0x7F  ./amfi-interpose.exe
   8 // RUN:  DYLD_AMFI_FAKE=0x3F  ./amfi-interpose.exe
   9
  10 //
  11 // Tests that AMFI_DYLD_OUTPUT_ALLOW_LIBRARY_INTERPOSING bit from AMFI blocks interposing
  12 //
  13
  14 #include <stdio.h>
  15 #include <stdbool.h>
  16 #include <stdlib.h>
  17 #include <string.h>
  18
  19 #include <libamfi.h>
  20
  21 int main()
  22 {
  23     printf("[BEGIN] amfi-interpose\n");
  24
  25     // interposed malloc() doubles alloction size and prefills allocation with '#'
  26     char* p1 = malloc(10);
  27     bool interposed = (strncmp(p1, "####################", 20) == 0);
  28
  29     const char* amfiBits = getenv("DYLD_AMFI_FAKE");
  30     if ( amfiBits == NULL ) {
  31         printf("[FAIL] amfi-interpose: DYLD_AMFI_FAKE not setn\n");
  32         return 0;
  33     }
  34 #ifdef AMFI_RETURNS_INTERPOSING_FLAG
  35     bool allowInterposing = (strcmp(amfiBits, "0x7F") == 0);
  36 #else
  37     bool allowInterposing = true;
  38 #endif
  39
  40     if ( interposed == allowInterposing )
  41         printf("[PASS] amfi-interpose\n");
  42     else if ( interposed )
  43         printf("[FAIL] amfi-interpose: malloc interposed, but amfi said to block it\n");
  44     else
  45         printf("[FAIL] amfi-interpose: malloc not interposed, but amfi said to allow it\n");
  46
  47         return 0;
  48 }