git.distorted.org.uk Git - u/mdw/putty/blob - mac/macnoise.c

   1 /*
   2  * Noise generation for PuTTY's cryptographic random number
   3  * generator.
   4  */
   5
   6 #include <Types.h>
   7 #include <Timer.h>
   8
   9 #include "putty.h"
  10 #include "ssh.h"
  11 #include "storage.h"
  12
  13 /*
  14  * This function is called once, at PuTTY startup, and will do some
  15  * seriously silly things like listing directories and getting disk
  16  * free space and a process snapshot.
  17  */
  18
  19 void noise_get_heavy(void (*func) (void *, int))
  20 {
  21
  22     read_random_seed(func);
  23     /* Update the seed immediately, in case another instance uses it. */
  24     random_save_seed();
  25 }
  26
  27 void random_save_seed(void)
  28 {
  29     int len;
  30     void *data;
  31
  32     if (random_active) {
  33         random_get_savedata(&data, &len);
  34         write_random_seed(data, len);
  35         sfree(data);
  36     }
  37 }
  38
  39 /*
  40  * This function is called every time the random pool needs
  41  * stirring, and will acquire the system time.
  42  */
  43 void noise_get_light(void (*func) (void *, int))
  44 {
  45     UnsignedWide utc;
  46
  47     Microseconds(&utc);
  48     func(&utc, sizeof(utc));
  49 }
  50
  51 /*
  52  * This function is called on every keypress or mouse move, and
  53  * will add the current time to the noise pool. It gets the scan
  54  * code or mouse position passed in, and adds that too.
  55  */
  56 void noise_ultralight(unsigned long data)
  57 {
  58     UnsignedWide utc;
  59
  60     Microseconds(&utc);
  61     random_add_noise(&utc, sizeof(utc));
  62     random_add_noise(&data, sizeof(data));
  63 }
  64
  65 /*
  66  * Local Variables:
  67  * c-file-style: "simon"
  68  * End:
  69  */