bss_mem.c revision 296341 
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
94BIO *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
117static int mem_new(BIO *bi)
118{
119    BUF_MEM *b;
120
121    if ((b = BUF_MEM_new()) == NULL)
122        return (0);
123    bi->shutdown = 1;
124    bi->init = 1;
125    bi->num = -1;
126    bi->ptr = (char *)b;
127    return (1);
128}
129
130static int mem_free(BIO *a)
131{
132    if (a == NULL)
133        return (0);
134    if (a->shutdown) {
135        if ((a->init) && (a->ptr != NULL)) {
136            BUF_MEM *b;
137            b = (BUF_MEM *)a->ptr;
138            if (a->flags & BIO_FLAGS_MEM_RDONLY)
139                b->data = NULL;
140            BUF_MEM_free(b);
141            a->ptr = NULL;
142        }
143    }
144    return (1);
145}
146
147static int mem_read(BIO *b, char *out, int outl)
148{
149    int ret = -1;
150    BUF_MEM *bm;
151
152    bm = (BUF_MEM *)b->ptr;
153    BIO_clear_retry_flags(b);
154    ret = (outl >= 0 && (size_t)outl > bm->length) ? (int)bm->length : outl;
155    if ((out != NULL) && (ret > 0)) {
156        memcpy(out, bm->data, ret);
157        bm->length -= ret;
158        if (b->flags & BIO_FLAGS_MEM_RDONLY)
159            bm->data += ret;
160        else {
161            memmove(&(bm->data[0]), &(bm->data[ret]), bm->length);
162        }
163    } else if (bm->length == 0) {
164        ret = b->num;
165        if (ret != 0)
166            BIO_set_retry_read(b);
167    }
168    return (ret);
169}
170
171static int mem_write(BIO *b, const char *in, int inl)
172{
173    int ret = -1;
174    int blen;
175    BUF_MEM *bm;
176
177    bm = (BUF_MEM *)b->ptr;
178    if (in == NULL) {
179        BIOerr(BIO_F_MEM_WRITE, BIO_R_NULL_PARAMETER);
180        goto end;
181    }
182
183    if (b->flags & BIO_FLAGS_MEM_RDONLY) {
184        BIOerr(BIO_F_MEM_WRITE, BIO_R_WRITE_TO_READ_ONLY_BIO);
185        goto end;
186    }
187
188    BIO_clear_retry_flags(b);
189    blen = bm->length;
190    if (BUF_MEM_grow_clean(bm, blen + inl) != (blen + inl))
191        goto end;
192    memcpy(&(bm->data[blen]), in, inl);
193    ret = inl;
194 end:
195    return (ret);
196}
197
198static long mem_ctrl(BIO *b, int cmd, long num, void *ptr)
199{
200    long ret = 1;
201    char **pptr;
202
203    BUF_MEM *bm = (BUF_MEM *)b->ptr;
204
205    switch (cmd) {
206    case BIO_CTRL_RESET:
207        if (bm->data != NULL) {
208            /* For read only case reset to the start again */
209            if (b->flags & BIO_FLAGS_MEM_RDONLY) {
210                bm->data -= bm->max - bm->length;
211                bm->length = bm->max;
212            } else {
213                memset(bm->data, 0, bm->max);
214                bm->length = 0;
215            }
216        }
217        break;
218    case BIO_CTRL_EOF:
219        ret = (long)(bm->length == 0);
220        break;
221    case BIO_C_SET_BUF_MEM_EOF_RETURN:
222        b->num = (int)num;
223        break;
224    case BIO_CTRL_INFO:
225        ret = (long)bm->length;
226        if (ptr != NULL) {
227            pptr = (char **)ptr;
228            *pptr = (char *)&(bm->data[0]);
229        }
230        break;
231    case BIO_C_SET_BUF_MEM:
232        mem_free(b);
233        b->shutdown = (int)num;
234        b->ptr = ptr;
235        break;
236    case BIO_C_GET_BUF_MEM_PTR:
237        if (ptr != NULL) {
238            pptr = (char **)ptr;
239            *pptr = (char *)bm;
240        }
241        break;
242    case BIO_CTRL_GET_CLOSE:
243        ret = (long)b->shutdown;
244        break;
245    case BIO_CTRL_SET_CLOSE:
246        b->shutdown = (int)num;
247        break;
248
249    case BIO_CTRL_WPENDING:
250        ret = 0L;
251        break;
252    case BIO_CTRL_PENDING:
253        ret = (long)bm->length;
254        break;
255    case BIO_CTRL_DUP:
256    case BIO_CTRL_FLUSH:
257        ret = 1;
258        break;
259    case BIO_CTRL_PUSH:
260    case BIO_CTRL_POP:
261    default:
262        ret = 0;
263        break;
264    }
265    return (ret);
266}
267
268static int mem_gets(BIO *bp, char *buf, int size)
269{
270    int i, j;
271    int ret = -1;
272    char *p;
273    BUF_MEM *bm = (BUF_MEM *)bp->ptr;
274
275    BIO_clear_retry_flags(bp);
276    j = bm->length;
277    if ((size - 1) < j)
278        j = size - 1;
279    if (j <= 0) {
280        *buf = '\0';
281        return 0;
282    }
283    p = bm->data;
284    for (i = 0; i < j; i++) {
285        if (p[i] == '\n') {
286            i++;
287            break;
288        }
289    }
290
291    /*
292     * i is now the max num of bytes to copy, either j or up to
293     * and including the first newline
294     */
295
296    i = mem_read(bp, buf, i);
297    if (i > 0)
298        buf[i] = '\0';
299    ret = i;
300    return (ret);
301}
302
303static int mem_puts(BIO *bp, const char *str)
304{
305    int n, ret;
306
307    n = strlen(str);
308    ret = mem_write(bp, str, n);
309    /* memory semantics is that it will always work */
310    return (ret);
311}
312