xref: /openbsd-src/lib/libcrypto/bio/bf_nbio.c (revision 50b7afb2c2c0993b0894d4e34bf857cb13ed9c80)
1 /* $OpenBSD: bf_nbio.c,v 1.17 2014/07/11 08:44:47 jsing Exp $ */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3  * All rights reserved.
4  *
5  * This package is an SSL implementation written
6  * by Eric Young (eay@cryptsoft.com).
7  * The implementation was written so as to conform with Netscapes SSL.
8  *
9  * This library is free for commercial and non-commercial use as long as
10  * the following conditions are aheared to.  The following conditions
11  * apply to all code found in this distribution, be it the RC4, RSA,
12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13  * included with this distribution is covered by the same copyright terms
14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15  *
16  * Copyright remains Eric Young's, and as such any Copyright notices in
17  * the code are not to be removed.
18  * If this package is used in a product, Eric Young should be given attribution
19  * as the author of the parts of the library used.
20  * This can be in the form of a textual message at program startup or
21  * in documentation (online or textual) provided with the package.
22  *
23  * Redistribution and use in source and binary forms, with or without
24  * modification, are permitted provided that the following conditions
25  * are met:
26  * 1. Redistributions of source code must retain the copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  * 3. All advertising materials mentioning features or use of this software
32  *    must display the following acknowledgement:
33  *    "This product includes cryptographic software written by
34  *     Eric Young (eay@cryptsoft.com)"
35  *    The word 'cryptographic' can be left out if the rouines from the library
36  *    being used are not cryptographic related :-).
37  * 4. If you include any Windows specific code (or a derivative thereof) from
38  *    the apps directory (application code) you must include an acknowledgement:
39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40  *
41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51  * SUCH DAMAGE.
52  *
53  * The licence and distribution terms for any publically available version or
54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
55  * copied and put under another distribution licence
56  * [including the GNU Public Licence.]
57  */
58 
59 #include <errno.h>
60 #include <stdio.h>
61 
62 #include <openssl/bio.h>
63 #include <openssl/rand.h>
64 
65 /* BIO_put and BIO_get both add to the digest,
66  * BIO_gets returns the digest */
67 
68 static int nbiof_write(BIO *h, const char *buf, int num);
69 static int nbiof_read(BIO *h, char *buf, int size);
70 static int nbiof_puts(BIO *h, const char *str);
71 static int nbiof_gets(BIO *h, char *str, int size);
72 static long nbiof_ctrl(BIO *h, int cmd, long arg1, void *arg2);
73 static int nbiof_new(BIO *h);
74 static int nbiof_free(BIO *data);
75 static long nbiof_callback_ctrl(BIO *h, int cmd, bio_info_cb *fp);
76 
77 typedef struct nbio_test_st {
78 	/* only set if we sent a 'should retry' error */
79 	int lrn;
80 	int lwn;
81 } NBIO_TEST;
82 
83 static BIO_METHOD methods_nbiof = {
84 	.type = BIO_TYPE_NBIO_TEST,
85 	.name = "non-blocking IO test filter",
86 	.bwrite = nbiof_write,
87 	.bread = nbiof_read,
88 	.bputs = nbiof_puts,
89 	.bgets = nbiof_gets,
90 	.ctrl = nbiof_ctrl,
91 	.create = nbiof_new,
92 	.destroy = nbiof_free,
93 	.callback_ctrl = nbiof_callback_ctrl
94 };
95 
96 BIO_METHOD *
97 BIO_f_nbio_test(void)
98 {
99 	return (&methods_nbiof);
100 }
101 
102 static int
103 nbiof_new(BIO *bi)
104 {
105 	NBIO_TEST *nt;
106 
107 	if (!(nt = malloc(sizeof(NBIO_TEST))))
108 		return (0);
109 	nt->lrn = -1;
110 	nt->lwn = -1;
111 	bi->ptr = (char *)nt;
112 	bi->init = 1;
113 	bi->flags = 0;
114 	return (1);
115 }
116 
117 static int
118 nbiof_free(BIO *a)
119 {
120 	if (a == NULL)
121 		return (0);
122 	free(a->ptr);
123 	a->ptr = NULL;
124 	a->init = 0;
125 	a->flags = 0;
126 	return (1);
127 }
128 
129 static int
130 nbiof_read(BIO *b, char *out, int outl)
131 {
132 	int ret = 0;
133 #if 1
134 	int num;
135 	unsigned char n;
136 #endif
137 
138 	if (out == NULL)
139 		return (0);
140 	if (b->next_bio == NULL)
141 		return (0);
142 
143 	BIO_clear_retry_flags(b);
144 #if 1
145 	RAND_pseudo_bytes(&n, 1);
146 	num = (n & 0x07);
147 
148 	if (outl > num)
149 		outl = num;
150 
151 	if (num == 0) {
152 		ret = -1;
153 		BIO_set_retry_read(b);
154 	} else
155 #endif
156 	{
157 		ret = BIO_read(b->next_bio, out, outl);
158 		if (ret < 0)
159 			BIO_copy_next_retry(b);
160 	}
161 	return (ret);
162 }
163 
164 static int
165 nbiof_write(BIO *b, const char *in, int inl)
166 {
167 	NBIO_TEST *nt;
168 	int ret = 0;
169 	int num;
170 	unsigned char n;
171 
172 	if ((in == NULL) || (inl <= 0))
173 		return (0);
174 	if (b->next_bio == NULL)
175 		return (0);
176 	nt = (NBIO_TEST *)b->ptr;
177 
178 	BIO_clear_retry_flags(b);
179 
180 #if 1
181 	if (nt->lwn > 0) {
182 		num = nt->lwn;
183 		nt->lwn = 0;
184 	} else {
185 		RAND_pseudo_bytes(&n, 1);
186 		num = (n&7);
187 	}
188 
189 	if (inl > num)
190 		inl = num;
191 
192 	if (num == 0) {
193 		ret = -1;
194 		BIO_set_retry_write(b);
195 	} else
196 #endif
197 	{
198 		ret = BIO_write(b->next_bio, in, inl);
199 		if (ret < 0) {
200 			BIO_copy_next_retry(b);
201 			nt->lwn = inl;
202 		}
203 	}
204 	return (ret);
205 }
206 
207 static long
208 nbiof_ctrl(BIO *b, int cmd, long num, void *ptr)
209 {
210 	long ret;
211 
212 	if (b->next_bio == NULL)
213 		return (0);
214 	switch (cmd) {
215 	case BIO_C_DO_STATE_MACHINE:
216 		BIO_clear_retry_flags(b);
217 		ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
218 		BIO_copy_next_retry(b);
219 		break;
220 	case BIO_CTRL_DUP:
221 		ret = 0L;
222 		break;
223 	default:
224 		ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
225 		break;
226 	}
227 	return (ret);
228 }
229 
230 static long
231 nbiof_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp)
232 {
233 	long ret = 1;
234 
235 	if (b->next_bio == NULL)
236 		return (0);
237 	switch (cmd) {
238 	default:
239 		ret = BIO_callback_ctrl(b->next_bio, cmd, fp);
240 		break;
241 	}
242 	return (ret);
243 }
244 
245 static int
246 nbiof_gets(BIO *bp, char *buf, int size)
247 {
248 	if (bp->next_bio == NULL)
249 		return (0);
250 	return (BIO_gets(bp->next_bio, buf, size));
251 }
252 
253 static int
254 nbiof_puts(BIO *bp, const char *str)
255 {
256 	if (bp->next_bio == NULL)
257 		return (0);
258 	return (BIO_puts(bp->next_bio, str));
259 }
260