c/cano/old/cano2.c

   1 #define _GNU_SOURCE
   2 #include <stdlib.h>
   3 #include <stdio.h>
   4 #include <sys/types.h>
   5 #include <sys/syscall.h>
   6 #include <dlfcn.h>
   7 #include <unistd.h>
   8 #include <stdarg.h>
   9 #include <time.h>
  10 #include <string.h>
  11
  12 #define i { srand(23); printf("%s();\n",__func__); }
  13 //Catch open() calls (while redirecting filename):
  14 static const char *redirect_name(const char *name)
  15 {
  16         if(
  17                 (strcmp(name,"/dev/random") == 0) ||
  18                 (strcmp(name,"/dev/urandom") == 0)
  19         ) {
  20                 printf("REDIRECT HIT: %s\n", name);
  21                 return "/dev/zero";
  22         }
  23         return name;
  24 }
  25
  26
  27 int open(const char *filename, int flags, ...)
  28 {
  29         //srand(23);
  30         static int (*open_orig)(const char *, int, mode_t);
  31         int ret;
  32         va_list ap;
  33         mode_t mode;
  34
  35         if (!open_orig) {
  36                 open_orig = dlsym(RTLD_NEXT, "open");
  37         }
  38
  39         va_start(ap, flags);
  40         mode = va_arg(ap, mode_t);
  41         va_end(ap);
  42
  43         if(strcmp(filename,"/tmp/a") != 0) {
  44                 ret = open_orig(redirect_name(filename), flags, mode);
  45                 //ret = syscall(SYS_open,redirect_name(filename),flags,mode);
  46         } else {
  47                 ret = popen("tee aaaa", "w");
  48         }
  49
  50         printf("open(\"%s\", 0x%x, %o) -> %d\n", filename, flags, mode, ret);
  51
  52         return ret;
  53 }
  54
  55 int open64(const char *filename, int flags, ...)
  56 {
  57         //srand(23);
  58         static int (*open64_orig)(const char *, int, mode_t);
  59         int ret;
  60         va_list ap;
  61         mode_t mode;
  62
  63         if (!open64_orig) {
  64                 open64_orig = dlsym(RTLD_NEXT, "open64");
  65         }
  66
  67         va_start(ap, flags);
  68         mode = va_arg(ap, mode_t);
  69         va_end(ap);
  70
  71         if(strcmp(filename,"/tmp/a") != 0) {
  72                 ret = open64_orig(redirect_name(filename), flags, mode);
  73                 //ret = syscall(SYS_open64,redirect_name(filename),flags,mode);
  74         } else {
  75                 ret = popen("tee aaaa", "w");
  76         }
  77
  78         printf("open64(\"%s\", 0x%x, %o) -> %d\n", filename, flags, mode, ret);
  79
  80         return ret;
  81 }