bss_mem.c revision 337982 
1/* crypto/bio/bss_mem.c */
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
64static int mem_write(BIO *h, const char *buf, int num);
65static int mem_read(BIO *h, char *buf, int size);
66static int mem_puts(BIO *h, const char *str);
67static int mem_gets(BIO *h, char *str, int size);
68static long mem_ctrl(BIO *h, int cmd, long arg1, void *arg2);
69static int mem_new(BIO *h);
70static int mem_free(BIO *data);
71static BIO_METHOD mem_method = {
72    BIO_TYPE_MEM,
73    "memory buffer",
74    mem_write,
75    mem_read,
76    mem_puts,
77    mem_gets,
78    mem_ctrl,
79    mem_new,
80    mem_free,
81    NULL,
82};
83
84/*
85 * bio->num is used to hold the value to return on 'empty', if it is 0,
86 * should_retry is not set
87 */
88
89BIO_METHOD *BIO_s_mem(void)
90{
91    return (&mem_method);
92}
93
94
95BIO *BIO_new_mem_buf(const void *buf, int len)
96{
97    BIO *ret;
98    BUF_MEM *b;
99    size_t sz;
100
101    if (!buf) {
102        BIOerr(BIO_F_BIO_NEW_MEM_BUF, BIO_R_NULL_PARAMETER);
103        return NULL;
104    }
105    sz = (len < 0) ? strlen(buf) : (size_t)len;
106    if (!(ret = BIO_new(BIO_s_mem())))
107        return NULL;
108    b = (BUF_MEM *)ret->ptr;
109    /* Cast away const and trust in the MEM_RDONLY flag. */
110    b->data = (void *)buf;
111    b->length = sz;
112    b->max = sz;
113    ret->flags |= BIO_FLAGS_MEM_RDONLY;
114    /* Since this is static data retrying wont help */
115    ret->num = 0;
116    return ret;
117}
118
119static int mem_new(BIO *bi)
120{
121    BUF_MEM *b;
122
123    if ((b = BUF_MEM_new()) == NULL)
124        return (0);
125    bi->shutdown = 1;
126    bi->init = 1;
127    bi->num = -1;
128    bi->ptr = (char *)b;
129    return (1);
130}
131
132static int 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
149static int mem_read(BIO *b, char *out, int outl)
150{
151    int ret = -1;
152    BUF_MEM *bm;
153
154    bm = (BUF_MEM *)b->ptr;
155    BIO_clear_retry_flags(b);
156    ret = (outl >= 0 && (size_t)outl > bm->length) ? (int)bm->length : outl;
157    if ((out != NULL) && (ret > 0)) {
158        memcpy(out, bm->data, ret);
159        bm->length -= ret;
160        if (b->flags & BIO_FLAGS_MEM_RDONLY)
161            bm->data += ret;
162        else {
163            memmove(&(bm->data[0]), &(bm->data[ret]), bm->length);
164        }
165    } else if (bm->length == 0) {
166        ret = b->num;
167        if (ret != 0)
168            BIO_set_retry_read(b);
169    }
170    return (ret);
171}
172
173static int mem_write(BIO *b, const char *in, int inl)
174{
175    int ret = -1;
176    int blen;
177    BUF_MEM *bm;
178
179    bm = (BUF_MEM *)b->ptr;
180    if (in == NULL) {
181        BIOerr(BIO_F_MEM_WRITE, BIO_R_NULL_PARAMETER);
182        goto end;
183    }
184
185    if (b->flags & BIO_FLAGS_MEM_RDONLY) {
186        BIOerr(BIO_F_MEM_WRITE, BIO_R_WRITE_TO_READ_ONLY_BIO);
187        goto end;
188    }
189
190    BIO_clear_retry_flags(b);
191    if (inl == 0)
192        return 0;
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
202static long mem_ctrl(BIO *b, int cmd, long num, void *ptr)
203{
204    long ret = 1;
205    char **pptr;
206
207    BUF_MEM *bm = (BUF_MEM *)b->ptr;
208
209    switch (cmd) {
210    case BIO_CTRL_RESET:
211        if (bm->data != NULL) {
212            /* For read only case reset to the start again */
213            if (b->flags & BIO_FLAGS_MEM_RDONLY) {
214                bm->data -= bm->max - bm->length;
215                bm->length = bm->max;
216            } else {
217                memset(bm->data, 0, bm->max);
218                bm->length = 0;
219            }
220        }
221        break;
222    case BIO_CTRL_EOF:
223        ret = (long)(bm->length == 0);
224        break;
225    case BIO_C_SET_BUF_MEM_EOF_RETURN:
226        b->num = (int)num;
227        break;
228    case BIO_CTRL_INFO:
229        ret = (long)bm->length;
230        if (ptr != NULL) {
231            pptr = (char **)ptr;
232            *pptr = (char *)&(bm->data[0]);
233        }
234        break;
235    case BIO_C_SET_BUF_MEM:
236        mem_free(b);
237        b->shutdown = (int)num;
238        b->ptr = ptr;
239        break;
240    case BIO_C_GET_BUF_MEM_PTR:
241        if (ptr != NULL) {
242            pptr = (char **)ptr;
243            *pptr = (char *)bm;
244        }
245        break;
246    case BIO_CTRL_GET_CLOSE:
247        ret = (long)b->shutdown;
248        break;
249    case BIO_CTRL_SET_CLOSE:
250        b->shutdown = (int)num;
251        break;
252
253    case BIO_CTRL_WPENDING:
254        ret = 0L;
255        break;
256    case BIO_CTRL_PENDING:
257        ret = (long)bm->length;
258        break;
259    case BIO_CTRL_DUP:
260    case BIO_CTRL_FLUSH:
261        ret = 1;
262        break;
263    case BIO_CTRL_PUSH:
264    case BIO_CTRL_POP:
265    default:
266        ret = 0;
267        break;
268    }
269    return (ret);
270}
271
272static int mem_gets(BIO *bp, char *buf, int size)
273{
274    int i, j;
275    int ret = -1;
276    char *p;
277    BUF_MEM *bm = (BUF_MEM *)bp->ptr;
278
279    BIO_clear_retry_flags(bp);
280    j = bm->length;
281    if ((size - 1) < j)
282        j = size - 1;
283    if (j <= 0) {
284        *buf = '\0';
285        return 0;
286    }
287    p = bm->data;
288    for (i = 0; i < j; i++) {
289        if (p[i] == '\n') {
290            i++;
291            break;
292        }
293    }
294
295    /*
296     * i is now the max num of bytes to copy, either j or up to
297     * and including the first newline
298     */
299
300    i = mem_read(bp, buf, i);
301    if (i > 0)
302        buf[i] = '\0';
303    ret = i;
304    return (ret);
305}
306
307static int mem_puts(BIO *bp, const char *str)
308{
309    int n, ret;
310
311    n = strlen(str);
312    ret = mem_write(bp, str, n);
313    /* memory semantics is that it will always work */
314    return (ret);
315}
316