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 } 114