source/libs/zziplib/zziplib-0.13.62/bins/zzxorcat.c

   1 /*
   2  *      Copyright (c) 2000,2001,2002 Guido Draheim <guidod@gmx.de>
   3  *      Use freely under the restrictions of the ZLIB License
   4  *
   5  *      show zip-reading with xor-obfuscation.
   6  *      Note that the difference to the standard zzcat.c is quite small.
   7  */
   8
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12 #include <ctype.h>
  13 #include <zzip/zzip.h>
  14 #include <zzip/plugin.h>
  15
  16 #if defined ZZIP_HAVE_UNISTD_H
  17 #include <unistd.h>
  18 #elif defined ZZIP_HAVE_IO_H
  19 #include <io.h>
  20 #else
  21 #error need posix io for this example
  22 #endif
  23
  24 #ifndef O_BINARY
  25 #define O_BINARY 0
  26 #endif
  27
  28 static const char usage[] =
  29 {
  30     " zzxorcat [-#] <file>... \n"
  31     "  - prints the file to stdout, so you may want to redirect the output; \n"
  32     " the file is part of an inflated zip-archive obfuscated with xor value,\n"
  33     " given by the numeric option (default is 0x55). \n"
  34     " to get 'README' from dist.dat you may write \n"
  35     "    zzcat dist/README \n"
  36 };
  37
  38 static int xor_value;
  39
  40 static zzip_ssize_t xor_read (int f, void* p, zzip_size_t l)
  41 {
  42     zzip_ssize_t r = read(f, p, l);
  43     zzip_ssize_t x; char* q; for (x=0, q=p; x < r; x++) q[x] ^= xor_value;
  44     return r;
  45 }
  46
  47 static zzip_plugin_io_handlers xor_handlers;
  48 static zzip_strings_t xor_fileext[] = { ".dat", "", 0 };
  49
  50 int
  51 main (int argc, char ** argv)
  52 {
  53     int argn;
  54     xor_value = 0x55;
  55
  56     if (argc <= 1 || ! strcmp (argv[1], "--help"))
  57     {
  58         printf (usage);
  59         return 0;
  60     }
  61     if (! strcmp (argv[1], "--version"))
  62     {
  63         printf (__FILE__" version "ZZIP_PACKAGE" "ZZIP_VERSION"\n");
  64         return 0;
  65     }
  66
  67     zzip_init_io (&xor_handlers, 0); xor_handlers.fd.read = &xor_read;
  68
  69     for (argn=1; argn < argc; argn++)
  70     {
  71         ZZIP_FILE* fp;
  72
  73         if (argv[argn][0] == '-')
  74         {
  75             if (isdigit(argv[argn][1])) xor_value = atoi (argv[argn]+1);
  76             continue;
  77         }
  78
  79         fp = zzip_open_ext_io (argv[argn], O_RDONLY|O_BINARY,
  80                                ZZIP_CASELESS|ZZIP_ONLYZIP,
  81                                xor_fileext, &xor_handlers);
  82         if (! fp)
  83         {
  84             perror (argv[argn]);
  85             continue;
  86         }else{
  87             char buf[17];
  88             zzip_ssize_t n;
  89
  90             /* read chunks of 16 bytes into buf and print them to stdout */
  91             while (0 < (n = zzip_read(fp, buf, 16)))
  92             {
  93                 buf[n] = '\0';
  94 #             ifdef STDOUT_FILENO
  95                 write (STDOUT_FILENO, buf, n);
  96 #             else
  97                 fwrite (buf, 1, n, stdout);
  98 #             endif
  99             }
 100
 101             if (n == -1)
 102                 perror (argv[n]);
 103         }
 104     }
 105
 106     return 0;
 107 }
 108
 109 /*
 110  * Local variables:
 111  * c-file-style: "stroustrup"
 112  * End:
 113  */