libotp.h

   1 /** Practical One-time Pad Library
   2  *
   3  * Created:20080514
   4  * By Jeff Connelly
   5  */
   6
   7 #define MARKER_TO               "to:"
   8 #define MARKER_BEGIN            "--EMOTP_BEGIN--"
   9 #define MARKER_END              "--EMOTP_END--"
  10
  11 #define OFFSET_FILE_EXTENSION   ".off"
  12 #define OFFSET_SIZE             11      /* strlen("4294967296") + 1 */
  13
  14 #define PAD_NAME_LENGTH         4
  15
  16 /* One-time pad. */
  17 typedef struct _PAD {
  18     char *local_filename;
  19     char *name;
  20     FILE *fp;
  21     struct _PAD *next;
  22     /* Use read_offset() and write_offset() to access offset. */
  23 } PAD;
  24
  25
  26 /** Packaged up encrypted message, ready for transport. */
  27 typedef struct _MESSAGE {
  28     unsigned long offset;
  29     PAD *pad;
  30     unsigned long length;
  31     char *cipher_text;
  32 } MESSAGE;
  33
  34 void show_pads();
  35 FILE *open_offset_file(PAD *p, char *mode);
  36 unsigned long read_offset(PAD *p);
  37 void write_offset(PAD *p, unsigned long offset);
  38 void load_pad(char *local_filename);
  39 void free_pads();
  40 MESSAGE *unpackage();
  41 void free_message(MESSAGE *);