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 #include <openssl/rand.h> 15 16 /* 17 * BIO_put and BIO_get both add to the digest, BIO_gets returns the digest 18 */ 19 20 static int nbiof_write(BIO *h, const char *buf, int num); 21 static int nbiof_read(BIO *h, char *buf, int size); 22 static int nbiof_puts(BIO *h, const char *str); 23 static int nbiof_gets(BIO *h, char *str, int size); 24 static long nbiof_ctrl(BIO *h, int cmd, long arg1, void *arg2); 25 static int nbiof_new(BIO *h); 26 static int nbiof_free(BIO *data); 27 static long nbiof_callback_ctrl(BIO *h, int cmd, BIO_info_cb *fp); 28 typedef struct nbio_test_st { 29 /* only set if we sent a 'should retry' error */ 30 int lrn; 31 int lwn; 32 } NBIO_TEST; 33 34 static const BIO_METHOD methods_nbiof = { 35 BIO_TYPE_NBIO_TEST, 36 "non-blocking IO test filter", 37 bwrite_conv, 38 nbiof_write, 39 bread_conv, 40 nbiof_read, 41 nbiof_puts, 42 nbiof_gets, 43 nbiof_ctrl, 44 nbiof_new, 45 nbiof_free, 46 nbiof_callback_ctrl, 47 }; 48 49 const BIO_METHOD *BIO_f_nbio_test(void) 50 { 51 return &methods_nbiof; 52 } 53 54 static int nbiof_new(BIO *bi) 55 { 56 NBIO_TEST *nt; 57 58 if ((nt = OPENSSL_zalloc(sizeof(*nt))) == NULL) { 59 ERR_raise(ERR_LIB_BIO, ERR_R_MALLOC_FAILURE); 60 return 0; 61 } 62 nt->lrn = -1; 63 nt->lwn = -1; 64 bi->ptr = (char *)nt; 65 bi->init = 1; 66 return 1; 67 } 68 69 static int nbiof_free(BIO *a) 70 { 71 if (a == NULL) 72 return 0; 73 OPENSSL_free(a->ptr); 74 a->ptr = NULL; 75 a->init = 0; 76 a->flags = 0; 77 return 1; 78 } 79 80 static int nbiof_read(BIO *b, char *out, int outl) 81 { 82 int ret = 0; 83 int num; 84 unsigned char n; 85 86 if (out == NULL) 87 return 0; 88 if (b->next_bio == NULL) 89 return 0; 90 91 BIO_clear_retry_flags(b); 92 if (RAND_priv_bytes(&n, 1) <= 0) 93 return -1; 94 num = (n & 0x07); 95 96 if (outl > num) 97 outl = num; 98 99 if (num == 0) { 100 ret = -1; 101 BIO_set_retry_read(b); 102 } else { 103 ret = BIO_read(b->next_bio, out, outl); 104 if (ret < 0) 105 BIO_copy_next_retry(b); 106 } 107 return ret; 108 } 109 110 static int nbiof_write(BIO *b, const char *in, int inl) 111 { 112 NBIO_TEST *nt; 113 int ret = 0; 114 int num; 115 unsigned char n; 116 117 if ((in == NULL) || (inl <= 0)) 118 return 0; 119 if (b->next_bio == NULL) 120 return 0; 121 nt = (NBIO_TEST *)b->ptr; 122 123 BIO_clear_retry_flags(b); 124 125 if (nt->lwn > 0) { 126 num = nt->lwn; 127 nt->lwn = 0; 128 } else { 129 if (RAND_priv_bytes(&n, 1) <= 0) 130 return -1; 131 num = (n & 7); 132 } 133 134 if (inl > num) 135 inl = num; 136 137 if (num == 0) { 138 ret = -1; 139 BIO_set_retry_write(b); 140 } else { 141 ret = BIO_write(b->next_bio, in, inl); 142 if (ret < 0) { 143 BIO_copy_next_retry(b); 144 nt->lwn = inl; 145 } 146 } 147 return ret; 148 } 149 150 static long nbiof_ctrl(BIO *b, int cmd, long num, void *ptr) 151 { 152 long ret; 153 154 if (b->next_bio == NULL) 155 return 0; 156 switch (cmd) { 157 case BIO_C_DO_STATE_MACHINE: 158 BIO_clear_retry_flags(b); 159 ret = BIO_ctrl(b->next_bio, cmd, num, ptr); 160 BIO_copy_next_retry(b); 161 break; 162 case BIO_CTRL_DUP: 163 ret = 0L; 164 break; 165 default: 166 ret = BIO_ctrl(b->next_bio, cmd, num, ptr); 167 break; 168 } 169 return ret; 170 } 171 172 static long nbiof_callback_ctrl(BIO *b, int cmd, BIO_info_cb *fp) 173 { 174 if (b->next_bio == NULL) 175 return 0; 176 return BIO_callback_ctrl(b->next_bio, cmd, fp); 177 } 178 179 static int nbiof_gets(BIO *bp, char *buf, int size) 180 { 181 if (bp->next_bio == NULL) 182 return 0; 183 return BIO_gets(bp->next_bio, buf, size); 184 } 185 186 static int nbiof_puts(BIO *bp, const char *str) 187 { 188 if (bp->next_bio == NULL) 189 return 0; 190 return BIO_puts(bp->next_bio, str); 191 } 192