git.distorted.org.uk Git - u/mdw/putty/blob - unix/uxgen.c

   1 /*
   2  * uxgen.c: Unix implementation of get_heavy_noise() from cmdgen.c.
   3  */
   4
   5 #include <stdio.h>
   6 #include <fcntl.h>
   7 #include <unistd.h>
   8
   9 #include "putty.h"
  10
  11 char *get_random_data(int len)
  12 {
  13     char *buf = snewn(len, char);
  14     int fd;
  15     int ngot, ret;
  16
  17     fd = open("/dev/random", O_RDONLY);
  18     if (fd < 0) {
  19         sfree(buf);
  20         perror("puttygen: unable to open /dev/random");
  21         return NULL;
  22     }
  23
  24     ngot = 0;
  25     while (ngot < len) {
  26         ret = read(fd, buf+ngot, len-ngot);
  27         if (ret < 0) {
  28             close(fd);
  29             sfree(buf);
  30             perror("puttygen: unable to read /dev/random");
  31             return NULL;
  32         }
  33         ngot += ret;
  34     }
  35
  36     close(fd);
  37
  38     return buf;
  39 }