1 /* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
2 /* lib/krb5/krb/random_str.c - Definition of krb5int_random_string() */
4 * Copyright (C) 2013 by the Massachusetts Institute of Technology.
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35 /* Utility routine: Creates a readable random string in a fixed size buffer. */
37 krb5int_random_string(krb5_context context, char *string, unsigned int length)
39 static const unsigned char charlist[] =
40 "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
41 krb5_error_code err = 0;
42 unsigned char *bytes = NULL;
43 unsigned int bytecount = length - 1;
46 bytes = malloc (bytecount);
47 if (bytes == NULL) { err = ENOMEM; }
52 data.length = bytecount;
53 data.data = (char *) bytes;
54 err = krb5_c_random_make_octets (context, &data);
59 for (i = 0; i < bytecount; i++) {
60 string [i] = charlist[bytes[i] % (sizeof (charlist) - 1)];
62 string[length - 1] = '\0';
65 if (bytes != NULL) { free (bytes); }