xref: /openbsd-src/lib/libcrypto/bio/bss_mem.c (revision c3d6a26af7455bccce87985ff78ef0efc39b65e1)
1 /* $OpenBSD: bss_mem.c,v 1.11 2014/06/12 15:49:28 deraadt 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 <stdio.h>
60 #include <errno.h>
61 #include "cryptlib.h"
62 #include <openssl/bio.h>
63 
64 static int mem_write(BIO *h, const char *buf, int num);
65 static int mem_read(BIO *h, char *buf, int size);
66 static int mem_puts(BIO *h, const char *str);
67 static int mem_gets(BIO *h, char *str, int size);
68 static long mem_ctrl(BIO *h, int cmd, long arg1, void *arg2);
69 static int mem_new(BIO *h);
70 static int mem_free(BIO *data);
71 
72 static BIO_METHOD mem_method = {
73 	.type = BIO_TYPE_MEM,
74 	.name = "memory buffer",
75 	.bwrite = mem_write,
76 	.bread = mem_read,
77 	.bputs = mem_puts,
78 	.bgets = mem_gets,
79 	.ctrl = mem_ctrl,
80 	.create = mem_new,
81 	.destroy = mem_free
82 };
83 
84 /* bio->num is used to hold the value to return on 'empty', if it is
85  * 0, should_retry is not set */
86 
87 BIO_METHOD *
88 BIO_s_mem(void)
89 {
90 	return (&mem_method);
91 }
92 
93 BIO *
94 BIO_new_mem_buf(void *buf, int len)
95 {
96 	BIO *ret;
97 	BUF_MEM *b;
98 	size_t sz;
99 
100 	if (!buf) {
101 		BIOerr(BIO_F_BIO_NEW_MEM_BUF, BIO_R_NULL_PARAMETER);
102 		return NULL;
103 	}
104 	sz = (len < 0) ? strlen(buf) : (size_t)len;
105 	if (!(ret = BIO_new(BIO_s_mem())))
106 		return NULL;
107 	b = (BUF_MEM *)ret->ptr;
108 	b->data = buf;
109 	b->length = sz;
110 	b->max = sz;
111 	ret->flags |= BIO_FLAGS_MEM_RDONLY;
112 	/* Since this is static data retrying wont help */
113 	ret->num = 0;
114 	return ret;
115 }
116 
117 static int
118 mem_new(BIO *bi)
119 {
120 	BUF_MEM *b;
121 
122 	if ((b = BUF_MEM_new()) == NULL)
123 		return (0);
124 	bi->shutdown = 1;
125 	bi->init = 1;
126 	bi->num = -1;
127 	bi->ptr = (char *)b;
128 	return (1);
129 }
130 
131 static int
132 mem_free(BIO *a)
133 {
134 	if (a == NULL)
135 		return (0);
136 	if (a->shutdown) {
137 		if ((a->init) && (a->ptr != NULL)) {
138 			BUF_MEM *b;
139 			b = (BUF_MEM *)a->ptr;
140 			if (a->flags & BIO_FLAGS_MEM_RDONLY)
141 				b->data = NULL;
142 				BUF_MEM_free(b);
143 			a->ptr = NULL;
144 		}
145 	}
146 	return (1);
147 }
148 
149 static int
150 mem_read(BIO *b, char *out, int outl)
151 {
152 	int ret = -1;
153 	BUF_MEM *bm;
154 
155 	bm = (BUF_MEM *)b->ptr;
156 	BIO_clear_retry_flags(b);
157 	ret = (outl >=0 && (size_t)outl > bm->length) ? (int)bm->length : outl;
158 	if ((out != NULL) && (ret > 0)) {
159 		memcpy(out, bm->data, ret);
160 		bm->length -= ret;
161 		if (b->flags & BIO_FLAGS_MEM_RDONLY)
162 			bm->data += ret;
163 		else {
164 			memmove(&(bm->data[0]), &(bm->data[ret]), bm->length);
165 		}
166 	} else if (bm->length == 0) {
167 		ret = b->num;
168 		if (ret != 0)
169 			BIO_set_retry_read(b);
170 	}
171 	return (ret);
172 }
173 
174 static int
175 mem_write(BIO *b, const char *in, int inl)
176 {
177 	int ret = -1;
178 	int blen;
179 	BUF_MEM *bm;
180 
181 	bm = (BUF_MEM *)b->ptr;
182 	if (in == NULL) {
183 		BIOerr(BIO_F_MEM_WRITE, BIO_R_NULL_PARAMETER);
184 		goto end;
185 	}
186 
187 	if (b->flags & BIO_FLAGS_MEM_RDONLY) {
188 		BIOerr(BIO_F_MEM_WRITE, BIO_R_WRITE_TO_READ_ONLY_BIO);
189 		goto end;
190 	}
191 
192 	BIO_clear_retry_flags(b);
193 	blen = bm->length;
194 	if (BUF_MEM_grow_clean(bm, blen + inl) != (blen + inl))
195 		goto end;
196 	memcpy(&(bm->data[blen]), in, inl);
197 	ret = inl;
198 end:
199 	return (ret);
200 }
201 
202 static long
203 mem_ctrl(BIO *b, int cmd, long num, void *ptr)
204 {
205 	long ret = 1;
206 	char **pptr;
207 
208 	BUF_MEM *bm = (BUF_MEM *)b->ptr;
209 
210 	switch (cmd) {
211 	case BIO_CTRL_RESET:
212 		if (bm->data != NULL) {
213 			/* For read only case reset to the start again */
214 			if (b->flags & BIO_FLAGS_MEM_RDONLY) {
215 				bm->data -= bm->max - bm->length;
216 				bm->length = bm->max;
217 			} else {
218 				memset(bm->data, 0, bm->max);
219 				bm->length = 0;
220 			}
221 		}
222 		break;
223 	case BIO_CTRL_EOF:
224 		ret = (long)(bm->length == 0);
225 		break;
226 	case BIO_C_SET_BUF_MEM_EOF_RETURN:
227 		b->num = (int)num;
228 		break;
229 	case BIO_CTRL_INFO:
230 		ret = (long)bm->length;
231 		if (ptr != NULL) {
232 			pptr = (char **)ptr;
233 			*pptr = (char *)&(bm->data[0]);
234 		}
235 		break;
236 	case BIO_C_SET_BUF_MEM:
237 		mem_free(b);
238 		b->shutdown = (int)num;
239 		b->ptr = ptr;
240 		break;
241 	case BIO_C_GET_BUF_MEM_PTR:
242 		if (ptr != NULL) {
243 			pptr = (char **)ptr;
244 			*pptr = (char *)bm;
245 		}
246 		break;
247 	case BIO_CTRL_GET_CLOSE:
248 		ret = (long)b->shutdown;
249 		break;
250 	case BIO_CTRL_SET_CLOSE:
251 		b->shutdown = (int)num;
252 		break;
253 
254 	case BIO_CTRL_WPENDING:
255 		ret = 0L;
256 		break;
257 	case BIO_CTRL_PENDING:
258 		ret = (long)bm->length;
259 		break;
260 	case BIO_CTRL_DUP:
261 	case BIO_CTRL_FLUSH:
262 		ret = 1;
263 		break;
264 	case BIO_CTRL_PUSH:
265 	case BIO_CTRL_POP:
266 	default:
267 		ret = 0;
268 		break;
269 	}
270 	return (ret);
271 }
272 
273 static int
274 mem_gets(BIO *bp, char *buf, int size)
275 {
276 	int i, j;
277 	int ret = -1;
278 	char *p;
279 	BUF_MEM *bm = (BUF_MEM *)bp->ptr;
280 
281 	BIO_clear_retry_flags(bp);
282 	j = bm->length;
283 	if ((size - 1) < j)
284 		j = size - 1;
285 	if (j <= 0) {
286 		*buf = '\0';
287 		return 0;
288 	}
289 	p = bm->data;
290 	for (i = 0; i < j; i++) {
291 		if (p[i] == '\n') {
292 			i++;
293 			break;
294 		}
295 	}
296 
297 	/*
298 	 * i is now the max num of bytes to copy, either j or up to
299 	 * and including the first newline
300 	 */
301 
302 	i = mem_read(bp, buf, i);
303 	if (i > 0)
304 		buf[i] = '\0';
305 	ret = i;
306 	return (ret);
307 }
308 
309 static int
310 mem_puts(BIO *bp, const char *str)
311 {
312 	int n, ret;
313 
314 	n = strlen(str);
315 	ret = mem_write(bp, str, n);
316 	/* memory semantics is that it will always work */
317 	return (ret);
318 }
319