crypto/bio/bf_null.c

   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
  15 /*
  16  * BIO_put and BIO_get both add to the digest, BIO_gets returns the digest
  17  */
  18
  19 static int nullf_write(BIO *h, const char *buf, int num);
  20 static int nullf_read(BIO *h, char *buf, int size);
  21 static int nullf_puts(BIO *h, const char *str);
  22 static int nullf_gets(BIO *h, char *str, int size);
  23 static long nullf_ctrl(BIO *h, int cmd, long arg1, void *arg2);
  24 static long nullf_callback_ctrl(BIO *h, int cmd, BIO_info_cb *fp);
  25 static const BIO_METHOD methods_nullf = {
  26     BIO_TYPE_NULL_FILTER,
  27     "NULL filter",
  28     bwrite_conv,
  29     nullf_write,
  30     bread_conv,
  31     nullf_read,
  32     nullf_puts,
  33     nullf_gets,
  34     nullf_ctrl,
  35     NULL,
  36     NULL,
  37     nullf_callback_ctrl,
  38 };
  39
  40 const BIO_METHOD *BIO_f_null(void)
  41 {
  42     return &methods_nullf;
  43 }
  44
  45 static int nullf_read(BIO *b, char *out, int outl)
  46 {
  47     int ret = 0;
  48
  49     if (out == NULL)
  50         return 0;
  51     if (b->next_bio == NULL)
  52         return 0;
  53     ret = BIO_read(b->next_bio, out, outl);
  54     BIO_clear_retry_flags(b);
  55     BIO_copy_next_retry(b);
  56     return ret;
  57 }
  58
  59 static int nullf_write(BIO *b, const char *in, int inl)
  60 {
  61     int ret = 0;
  62
  63     if ((in == NULL) || (inl <= 0))
  64         return 0;
  65     if (b->next_bio == NULL)
  66         return 0;
  67     ret = BIO_write(b->next_bio, in, inl);
  68     BIO_clear_retry_flags(b);
  69     BIO_copy_next_retry(b);
  70     return ret;
  71 }
  72
  73 static long nullf_ctrl(BIO *b, int cmd, long num, void *ptr)
  74 {
  75     long ret;
  76
  77     if (b->next_bio == NULL)
  78         return 0;
  79     switch (cmd) {
  80     case BIO_C_DO_STATE_MACHINE:
  81         BIO_clear_retry_flags(b);
  82         ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
  83         BIO_copy_next_retry(b);
  84         break;
  85     case BIO_CTRL_DUP:
  86         ret = 0L;
  87         break;
  88     default:
  89         ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
  90     }
  91     return ret;
  92 }
  93
  94 static long nullf_callback_ctrl(BIO *b, int cmd, BIO_info_cb *fp)
  95 {
  96     if (b->next_bio == NULL)
  97         return 0;
  98     return BIO_callback_ctrl(b->next_bio, cmd, fp);
  99 }
 100
 101 static int nullf_gets(BIO *bp, char *buf, int size)
 102 {
 103     if (bp->next_bio == NULL)
 104         return 0;
 105     return BIO_gets(bp->next_bio, buf, size);
 106 }
 107
 108 static int nullf_puts(BIO *bp, const char *str)
 109 {
 110     if (bp->next_bio == NULL)
 111         return 0;
 112     return BIO_puts(bp->next_bio, str);
 113 }