This file is indexed.

/usr/include/coap/prng.h is in libcoap-1-0-dev 4.1.2-1.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
/*
 * prng.h -- Pseudo Random Numbers
 *
 * Copyright (C) 2010-2011 Olaf Bergmann <bergmann@tzi.org>
 *
 * This file is part of the CoAP library libcoap. Please see README for terms
 * of use.
 */

/**
 * @file prng.h
 * @brief Pseudo Random Numbers
 */

#ifndef _COAP_PRNG_H_
#define _COAP_PRNG_H_

/**
 * @defgroup prng Pseudo Random Numbers
 * @{
 */

#if defined(WITH_POSIX) || (defined(WITH_LWIP) && !defined(LWIP_RAND))
#include <stdlib.h>

/**
 * Fills \p buf with \p len random bytes. This is the default implementation for
 * prng(). You might want to change prng() to use a better PRNG on your specific
 * platform.
 */
static inline int
coap_prng_impl(unsigned char *buf, size_t len) {
  while (len--)
    *buf++ = rand() & 0xFF;
  return 1;
}
#endif /* WITH_POSIX */

#ifdef WITH_CONTIKI
#include <string.h>

/**
 * Fills \p buf with \p len random bytes. This is the default implementation for
 * prng(). You might want to change prng() to use a better PRNG on your specific
 * platform.
 */
static inline int
contiki_prng_impl(unsigned char *buf, size_t len) {
  unsigned short v = random_rand();
  while (len > sizeof(v)) {
    memcpy(buf, &v, sizeof(v));
    len -= sizeof(v);
    buf += sizeof(v);
    v = random_rand();
  }

  memcpy(buf, &v, len);
  return 1;
}

#define prng(Buf,Length) contiki_prng_impl((Buf), (Length))
#define prng_init(Value) random_init((unsigned short)(Value))
#endif /* WITH_CONTIKI */

#if defined(WITH_LWIP) && defined(LWIP_RAND)
static inline int
lwip_prng_impl(unsigned char *buf, size_t len) {
  u32_t v = LWIP_RAND();
  while (len > sizeof(v)) {
    memcpy(buf, &v, sizeof(v));
    len -= sizeof(v);
    buf += sizeof(v);
    v = LWIP_RAND();
  }

  memcpy(buf, &v, len);
  return 1;
}

#define prng(Buf,Length) lwip_prng_impl((Buf), (Length))
#define prng_init(Value)

#endif /* WITH_LWIP */

#ifndef prng
/**
 * Fills \p Buf with \p Length bytes of random data.
 *
 * @hideinitializer
 */
#define prng(Buf,Length) coap_prng_impl((Buf), (Length))
#endif

#ifndef prng_init
/**
 * Called to set the PRNG seed. You may want to re-define this to allow for a
 * better PRNG.
 *
 * @hideinitializer
 */
#define prng_init(Value) srand((unsigned long)(Value))
#endif

/** @} */

#endif /* _COAP_PRNG_H_ */