1/*
2 * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License").  You may not use
5 * this file except in compliance with the License.  You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10#include <stdio.h>
11#include <errno.h>
12#include "bio_local.h"
13#include "internal/cryptlib.h"
14
15static int null_write(BIO *h, const char *buf, int num);
16static int null_read(BIO *h, char *buf, int size);
17static int null_puts(BIO *h, const char *str);
18static int null_gets(BIO *h, char *str, int size);
19static long null_ctrl(BIO *h, int cmd, long arg1, void *arg2);
20static const BIO_METHOD null_method = {
21    BIO_TYPE_NULL,
22    "NULL",
23    bwrite_conv,
24    null_write,
25    bread_conv,
26    null_read,
27    null_puts,
28    null_gets,
29    null_ctrl,
30    NULL,
31    NULL,
32    NULL,                     /* null_callback_ctrl */
33};
34
35const BIO_METHOD *BIO_s_null(void)
36{
37    return &null_method;
38}
39
40static int null_read(BIO *b, char *out, int outl)
41{
42    return 0;
43}
44
45static int null_write(BIO *b, const char *in, int inl)
46{
47    return inl;
48}
49
50static long null_ctrl(BIO *b, int cmd, long num, void *ptr)
51{
52    long ret = 1;
53
54    switch (cmd) {
55    case BIO_CTRL_RESET:
56    case BIO_CTRL_EOF:
57    case BIO_CTRL_SET:
58    case BIO_CTRL_SET_CLOSE:
59    case BIO_CTRL_FLUSH:
60    case BIO_CTRL_DUP:
61        ret = 1;
62        break;
63    case BIO_CTRL_GET_CLOSE:
64    case BIO_CTRL_INFO:
65    case BIO_CTRL_GET:
66    case BIO_CTRL_PENDING:
67    case BIO_CTRL_WPENDING:
68    default:
69        ret = 0;
70        break;
71    }
72    return ret;
73}
74
75static int null_gets(BIO *bp, char *buf, int size)
76{
77    return 0;
78}
79
80static int null_puts(BIO *bp, const char *str)
81{
82    if (str == NULL)
83        return 0;
84    return strlen(str);
85}
86