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
BIO_f_nbio_test(void)49 const BIO_METHOD *BIO_f_nbio_test(void)
50 {
51 return &methods_nbiof;
52 }
53
nbiof_new(BIO * bi)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
nbiof_free(BIO * a)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
nbiof_read(BIO * b,char * out,int outl)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
nbiof_write(BIO * b,const char * in,int inl)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
nbiof_ctrl(BIO * b,int cmd,long num,void * ptr)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
nbiof_callback_ctrl(BIO * b,int cmd,BIO_info_cb * fp)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
nbiof_gets(BIO * bp,char * buf,int size)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
nbiof_puts(BIO * bp,const char * str)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