1/*
2 * Copyright 1995-2018 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
15static int mem_write(BIO *h, const char *buf, int num);
16static int mem_read(BIO *h, char *buf, int size);
17static int mem_puts(BIO *h, const char *str);
18static int mem_gets(BIO *h, char *str, int size);
19static long mem_ctrl(BIO *h, int cmd, long arg1, void *arg2);
20static int mem_new(BIO *h);
21static int secmem_new(BIO *h);
22static int mem_free(BIO *data);
23static int mem_buf_free(BIO *data);
24static int mem_buf_sync(BIO *h);
25
26static const BIO_METHOD mem_method = {
27 BIO_TYPE_MEM,
28 "memory buffer",
29 /* TODO: Convert to new style write function */
30 bwrite_conv,
31 mem_write,
32 /* TODO: Convert to new style read function */
33 bread_conv,
34 mem_read,
35 mem_puts,
36 mem_gets,
37 mem_ctrl,
38 mem_new,
39 mem_free,
40 NULL, /* mem_callback_ctrl */
41};
42
43static const BIO_METHOD secmem_method = {
44 BIO_TYPE_MEM,
45 "secure memory buffer",
46 /* TODO: Convert to new style write function */
47 bwrite_conv,
48 mem_write,
49 /* TODO: Convert to new style read function */
50 bread_conv,
51 mem_read,
52 mem_puts,
53 mem_gets,
54 mem_ctrl,
55 secmem_new,
56 mem_free,
57 NULL, /* mem_callback_ctrl */
58};
59
60/*
61 * BIO memory stores buffer and read pointer
62 * however the roles are different for read only BIOs.
63 * In that case the readp just stores the original state
64 * to be used for reset.
65 */
66typedef struct bio_buf_mem_st {
67 struct buf_mem_st *buf; /* allocated buffer */
68 struct buf_mem_st *readp; /* read pointer */
69} BIO_BUF_MEM;
70
71/*
72 * bio->num is used to hold the value to return on 'empty', if it is 0,
73 * should_retry is not set
74 */
75
76const BIO_METHOD *BIO_s_mem(void)
77{
78 return &mem_method;
79}
80
81const BIO_METHOD *BIO_s_secmem(void)
82{
83 return(&secmem_method);
84}
85
86BIO *BIO_new_mem_buf(const void *buf, int len)
87{
88 BIO *ret;
89 BUF_MEM *b;
90 BIO_BUF_MEM *bb;
91 size_t sz;
92
93 if (buf == NULL) {
94 BIOerr(BIO_F_BIO_NEW_MEM_BUF, BIO_R_NULL_PARAMETER);
95 return NULL;
96 }
97 sz = (len < 0) ? strlen(buf) : (size_t)len;
98 if ((ret = BIO_new(BIO_s_mem())) == NULL)
99 return NULL;
100 bb = (BIO_BUF_MEM *)ret->ptr;
101 b = bb->buf;
102 /* Cast away const and trust in the MEM_RDONLY flag. */
103 b->data = (void *)buf;
104 b->length = sz;
105 b->max = sz;
106 *bb->readp = *bb->buf;
107 ret->flags |= BIO_FLAGS_MEM_RDONLY;
108 /* Since this is static data retrying won't help */
109 ret->num = 0;
110 return ret;
111}
112
113static int mem_init(BIO *bi, unsigned long flags)
114{
115 BIO_BUF_MEM *bb = OPENSSL_zalloc(sizeof(*bb));
116
117 if (bb == NULL)
118 return 0;
119 if ((bb->buf = BUF_MEM_new_ex(flags)) == NULL) {
120 OPENSSL_free(bb);
121 return 0;
122 }
123 if ((bb->readp = OPENSSL_zalloc(sizeof(*bb->readp))) == NULL) {
124 BUF_MEM_free(bb->buf);
125 OPENSSL_free(bb);
126 return 0;
127 }
128 *bb->readp = *bb->buf;
129 bi->shutdown = 1;
130 bi->init = 1;
131 bi->num = -1;
132 bi->ptr = (char *)bb;
133 return 1;
134}
135
136static int mem_new(BIO *bi)
137{
138 return mem_init(bi, 0L);
139}
140
141static int secmem_new(BIO *bi)
142{
143 return mem_init(bi, BUF_MEM_FLAG_SECURE);
144}
145
146static int mem_free(BIO *a)
147{
148 BIO_BUF_MEM *bb;
149
150 if (a == NULL)
151 return 0;
152
153 bb = (BIO_BUF_MEM *)a->ptr;
154 if (!mem_buf_free(a))
155 return 0;
156 OPENSSL_free(bb->readp);
157 OPENSSL_free(bb);
158 return 1;
159}
160
161static int mem_buf_free(BIO *a)
162{
163 if (a == NULL)
164 return 0;
165
166 if (a->shutdown && a->init && a->ptr != NULL) {
167 BIO_BUF_MEM *bb = (BIO_BUF_MEM *)a->ptr;
168 BUF_MEM *b = bb->buf;
169
170 if (a->flags & BIO_FLAGS_MEM_RDONLY)
171 b->data = NULL;
172 BUF_MEM_free(b);
173 }
174 return 1;
175}
176
177/*
178 * Reallocate memory buffer if read pointer differs
179 */
180static int mem_buf_sync(BIO *b)
181{
182 if (b != NULL && b->init != 0 && b->ptr != NULL) {
183 BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)b->ptr;
184
185 if (bbm->readp->data != bbm->buf->data) {
186 memmove(bbm->buf->data, bbm->readp->data, bbm->readp->length);
187 bbm->buf->length = bbm->readp->length;
188 bbm->readp->data = bbm->buf->data;
189 }
190 }
191 return 0;
192}
193
194static int mem_read(BIO *b, char *out, int outl)
195{
196 int ret = -1;
197 BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)b->ptr;
198 BUF_MEM *bm = bbm->readp;
199
200 if (b->flags & BIO_FLAGS_MEM_RDONLY)
201 bm = bbm->buf;
202 BIO_clear_retry_flags(b);
203 ret = (outl >= 0 && (size_t)outl > bm->length) ? (int)bm->length : outl;
204 if ((out != NULL) && (ret > 0)) {
205 memcpy(out, bm->data, ret);
206 bm->length -= ret;
207 bm->max -= ret;
208 bm->data += ret;
209 } else if (bm->length == 0) {
210 ret = b->num;
211 if (ret != 0)
212 BIO_set_retry_read(b);
213 }
214 return ret;
215}
216
217static int mem_write(BIO *b, const char *in, int inl)
218{
219 int ret = -1;
220 int blen;
221 BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)b->ptr;
222
223 if (in == NULL) {
224 BIOerr(BIO_F_MEM_WRITE, BIO_R_NULL_PARAMETER);
225 goto end;
226 }
227 if (b->flags & BIO_FLAGS_MEM_RDONLY) {
228 BIOerr(BIO_F_MEM_WRITE, BIO_R_WRITE_TO_READ_ONLY_BIO);
229 goto end;
230 }
231 BIO_clear_retry_flags(b);
232 if (inl == 0)
233 return 0;
234 blen = bbm->readp->length;
235 mem_buf_sync(b);
236 if (BUF_MEM_grow_clean(bbm->buf, blen + inl) == 0)
237 goto end;
238 memcpy(bbm->buf->data + blen, in, inl);
239 *bbm->readp = *bbm->buf;
240 ret = inl;
241 end:
242 return ret;
243}
244
245static long mem_ctrl(BIO *b, int cmd, long num, void *ptr)
246{
247 long ret = 1;
248 char **pptr;
249 BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)b->ptr;
250 BUF_MEM *bm;
251
252 if (b->flags & BIO_FLAGS_MEM_RDONLY)
253 bm = bbm->buf;
254 else
255 bm = bbm->readp;
256
257 switch (cmd) {
258 case BIO_CTRL_RESET:
259 bm = bbm->buf;
260 if (bm->data != NULL) {
261 if (!(b->flags & BIO_FLAGS_MEM_RDONLY)) {
262 if (!(b->flags & BIO_FLAGS_NONCLEAR_RST)) {
263 memset(bm->data, 0, bm->max);
264 bm->length = 0;
265 }
266 *bbm->readp = *bbm->buf;
267 } else {
268 /* For read only case just reset to the start again */
269 *bbm->buf = *bbm->readp;
270 }
271 }
272 break;
273 case BIO_CTRL_EOF:
274 ret = (long)(bm->length == 0);
275 break;
276 case BIO_C_SET_BUF_MEM_EOF_RETURN:
277 b->num = (int)num;
278 break;
279 case BIO_CTRL_INFO:
280 ret = (long)bm->length;
281 if (ptr != NULL) {
282 pptr = (char **)ptr;
283 *pptr = (char *)&(bm->data[0]);
284 }
285 break;
286 case BIO_C_SET_BUF_MEM:
287 mem_buf_free(b);
288 b->shutdown = (int)num;
289 bbm->buf = ptr;
290 *bbm->readp = *bbm->buf;
291 break;
292 case BIO_C_GET_BUF_MEM_PTR:
293 if (ptr != NULL) {
294 if (!(b->flags & BIO_FLAGS_MEM_RDONLY))
295 mem_buf_sync(b);
296 bm = bbm->buf;
297 pptr = (char **)ptr;
298 *pptr = (char *)bm;
299 }
300 break;
301 case BIO_CTRL_GET_CLOSE:
302 ret = (long)b->shutdown;
303 break;
304 case BIO_CTRL_SET_CLOSE:
305 b->shutdown = (int)num;
306 break;
307 case BIO_CTRL_WPENDING:
308 ret = 0L;
309 break;
310 case BIO_CTRL_PENDING:
311 ret = (long)bm->length;
312 break;
313 case BIO_CTRL_DUP:
314 case BIO_CTRL_FLUSH:
315 ret = 1;
316 break;
317 case BIO_CTRL_PUSH:
318 case BIO_CTRL_POP:
319 default:
320 ret = 0;
321 break;
322 }
323 return ret;
324}
325
326static int mem_gets(BIO *bp, char *buf, int size)
327{
328 int i, j;
329 int ret = -1;
330 char *p;
331 BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)bp->ptr;
332 BUF_MEM *bm = bbm->readp;
333
334 if (bp->flags & BIO_FLAGS_MEM_RDONLY)
335 bm = bbm->buf;
336 BIO_clear_retry_flags(bp);
337 j = bm->length;
338 if ((size - 1) < j)
339 j = size - 1;
340 if (j <= 0) {
341 *buf = '\0';
342 return 0;
343 }
344 p = bm->data;
345 for (i = 0; i < j; i++) {
346 if (p[i] == '\n') {
347 i++;
348 break;
349 }
350 }
351
352 /*
353 * i is now the max num of bytes to copy, either j or up to
354 * and including the first newline
355 */
356
357 i = mem_read(bp, buf, i);
358 if (i > 0)
359 buf[i] = '\0';
360 ret = i;
361 return ret;
362}
363
364static int mem_puts(BIO *bp, const char *str)
365{
366 int n, ret;
367
368 n = strlen(str);
369 ret = mem_write(bp, str, n);
370 /* memory semantics is that it will always work */
371 return ret;
372}
373