1 /*
2 * Copyright 1995-2023 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
15 static int mem_write(BIO *h, const char *buf, int num);
16 static int mem_read(BIO *h, char *buf, int size);
17 static int mem_puts(BIO *h, const char *str);
18 static int mem_gets(BIO *h, char *str, int size);
19 static long mem_ctrl(BIO *h, int cmd, long arg1, void *arg2);
20 static int mem_new(BIO *h);
21 static int secmem_new(BIO *h);
22 static int mem_free(BIO *data);
23 static int mem_buf_free(BIO *data);
24 static int mem_buf_sync(BIO *h);
25
26 static const BIO_METHOD mem_method = {
27 BIO_TYPE_MEM,
28 "memory buffer",
29 bwrite_conv,
30 mem_write,
31 bread_conv,
32 mem_read,
33 mem_puts,
34 mem_gets,
35 mem_ctrl,
36 mem_new,
37 mem_free,
38 NULL, /* mem_callback_ctrl */
39 };
40
41 static const BIO_METHOD secmem_method = {
42 BIO_TYPE_MEM,
43 "secure memory buffer",
44 bwrite_conv,
45 mem_write,
46 bread_conv,
47 mem_read,
48 mem_puts,
49 mem_gets,
50 mem_ctrl,
51 secmem_new,
52 mem_free,
53 NULL, /* mem_callback_ctrl */
54 };
55
56 /*
57 * BIO memory stores buffer and read pointer
58 * however the roles are different for read only BIOs.
59 * In that case the readp just stores the original state
60 * to be used for reset.
61 */
62 typedef struct bio_buf_mem_st {
63 struct buf_mem_st *buf; /* allocated buffer */
64 struct buf_mem_st *readp; /* read pointer */
65 } BIO_BUF_MEM;
66
67 /*
68 * bio->num is used to hold the value to return on 'empty', if it is 0,
69 * should_retry is not set
70 */
71
BIO_s_mem(void)72 const BIO_METHOD *BIO_s_mem(void)
73 {
74 return &mem_method;
75 }
76
BIO_s_secmem(void)77 const BIO_METHOD *BIO_s_secmem(void)
78 {
79 return(&secmem_method);
80 }
81
BIO_new_mem_buf(const void * buf,int len)82 BIO *BIO_new_mem_buf(const void *buf, int len)
83 {
84 BIO *ret;
85 BUF_MEM *b;
86 BIO_BUF_MEM *bb;
87 size_t sz;
88
89 if (buf == NULL) {
90 ERR_raise(ERR_LIB_BIO, ERR_R_PASSED_NULL_PARAMETER);
91 return NULL;
92 }
93 sz = (len < 0) ? strlen(buf) : (size_t)len;
94 if ((ret = BIO_new(BIO_s_mem())) == NULL)
95 return NULL;
96 bb = (BIO_BUF_MEM *)ret->ptr;
97 b = bb->buf;
98 /* Cast away const and trust in the MEM_RDONLY flag. */
99 b->data = (void *)buf;
100 b->length = sz;
101 b->max = sz;
102 *bb->readp = *bb->buf;
103 ret->flags |= BIO_FLAGS_MEM_RDONLY;
104 /* Since this is static data retrying won't help */
105 ret->num = 0;
106 return ret;
107 }
108
mem_init(BIO * bi,unsigned long flags)109 static int mem_init(BIO *bi, unsigned long flags)
110 {
111 BIO_BUF_MEM *bb = OPENSSL_zalloc(sizeof(*bb));
112
113 if (bb == NULL)
114 return 0;
115 if ((bb->buf = BUF_MEM_new_ex(flags)) == NULL) {
116 OPENSSL_free(bb);
117 return 0;
118 }
119 if ((bb->readp = OPENSSL_zalloc(sizeof(*bb->readp))) == NULL) {
120 BUF_MEM_free(bb->buf);
121 OPENSSL_free(bb);
122 return 0;
123 }
124 *bb->readp = *bb->buf;
125 bi->shutdown = 1;
126 bi->init = 1;
127 bi->num = -1;
128 bi->ptr = (char *)bb;
129 return 1;
130 }
131
mem_new(BIO * bi)132 static int mem_new(BIO *bi)
133 {
134 return mem_init(bi, 0L);
135 }
136
secmem_new(BIO * bi)137 static int secmem_new(BIO *bi)
138 {
139 return mem_init(bi, BUF_MEM_FLAG_SECURE);
140 }
141
mem_free(BIO * a)142 static int mem_free(BIO *a)
143 {
144 BIO_BUF_MEM *bb;
145
146 if (a == NULL)
147 return 0;
148
149 bb = (BIO_BUF_MEM *)a->ptr;
150 if (!mem_buf_free(a))
151 return 0;
152 OPENSSL_free(bb->readp);
153 OPENSSL_free(bb);
154 return 1;
155 }
156
mem_buf_free(BIO * a)157 static int mem_buf_free(BIO *a)
158 {
159 if (a == NULL)
160 return 0;
161
162 if (a->shutdown && a->init && a->ptr != NULL) {
163 BIO_BUF_MEM *bb = (BIO_BUF_MEM *)a->ptr;
164 BUF_MEM *b = bb->buf;
165
166 if (a->flags & BIO_FLAGS_MEM_RDONLY)
167 b->data = NULL;
168 BUF_MEM_free(b);
169 }
170 return 1;
171 }
172
173 /*
174 * Reallocate memory buffer if read pointer differs
175 * NOT FOR RDONLY
176 */
mem_buf_sync(BIO * b)177 static int mem_buf_sync(BIO *b)
178 {
179 if (b != NULL && b->init != 0 && b->ptr != NULL) {
180 BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)b->ptr;
181
182 if (bbm->readp->data != bbm->buf->data) {
183 memmove(bbm->buf->data, bbm->readp->data, bbm->readp->length);
184 bbm->buf->length = bbm->readp->length;
185 bbm->readp->data = bbm->buf->data;
186 }
187 }
188 return 0;
189 }
190
mem_read(BIO * b,char * out,int outl)191 static int mem_read(BIO *b, char *out, int outl)
192 {
193 int ret = -1;
194 BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)b->ptr;
195 BUF_MEM *bm = bbm->readp;
196
197 if (b->flags & BIO_FLAGS_MEM_RDONLY)
198 bm = bbm->buf;
199 BIO_clear_retry_flags(b);
200 ret = (outl >= 0 && (size_t)outl > bm->length) ? (int)bm->length : outl;
201 if ((out != NULL) && (ret > 0)) {
202 memcpy(out, bm->data, ret);
203 bm->length -= ret;
204 bm->max -= ret;
205 bm->data += ret;
206 } else if (bm->length == 0) {
207 ret = b->num;
208 if (ret != 0)
209 BIO_set_retry_read(b);
210 }
211 return ret;
212 }
213
mem_write(BIO * b,const char * in,int inl)214 static int mem_write(BIO *b, const char *in, int inl)
215 {
216 int ret = -1;
217 int blen;
218 BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)b->ptr;
219
220 if (b->flags & BIO_FLAGS_MEM_RDONLY) {
221 ERR_raise(ERR_LIB_BIO, BIO_R_WRITE_TO_READ_ONLY_BIO);
222 goto end;
223 }
224 BIO_clear_retry_flags(b);
225 if (inl == 0)
226 return 0;
227 if (in == NULL) {
228 ERR_raise(ERR_LIB_BIO, ERR_R_PASSED_NULL_PARAMETER);
229 goto end;
230 }
231 blen = bbm->readp->length;
232 mem_buf_sync(b);
233 if (BUF_MEM_grow_clean(bbm->buf, blen + inl) == 0)
234 goto end;
235 memcpy(bbm->buf->data + blen, in, inl);
236 *bbm->readp = *bbm->buf;
237 ret = inl;
238 end:
239 return ret;
240 }
241
mem_ctrl(BIO * b,int cmd,long num,void * ptr)242 static long mem_ctrl(BIO *b, int cmd, long num, void *ptr)
243 {
244 long ret = 1;
245 char **pptr;
246 BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)b->ptr;
247 BUF_MEM *bm, *bo; /* bio_mem, bio_other */
248 long off, remain;
249
250 if (b->flags & BIO_FLAGS_MEM_RDONLY) {
251 bm = bbm->buf;
252 bo = bbm->readp;
253 } else {
254 bm = bbm->readp;
255 bo = bbm->buf;
256 }
257 off = (bm->data == bo->data) ? 0 : bm->data - bo->data;
258 remain = bm->length;
259
260 switch (cmd) {
261 case BIO_CTRL_RESET:
262 bm = bbm->buf;
263 if (bm->data != NULL) {
264 if (!(b->flags & BIO_FLAGS_MEM_RDONLY)) {
265 if (!(b->flags & BIO_FLAGS_NONCLEAR_RST)) {
266 memset(bm->data, 0, bm->max);
267 bm->length = 0;
268 }
269 *bbm->readp = *bbm->buf;
270 } else {
271 /* For read only case just reset to the start again */
272 *bbm->buf = *bbm->readp;
273 }
274 }
275 break;
276 case BIO_C_FILE_SEEK:
277 if (num < 0 || num > off + remain)
278 return -1; /* Can't see outside of the current buffer */
279
280 bm->data = (num != 0) ? bo->data + num : bo->data;
281 bm->length = bo->length - num;
282 bm->max = bo->max - num;
283 off = num;
284 /* FALLTHRU */
285 case BIO_C_FILE_TELL:
286 ret = off;
287 break;
288 case BIO_CTRL_EOF:
289 ret = (long)(bm->length == 0);
290 break;
291 case BIO_C_SET_BUF_MEM_EOF_RETURN:
292 b->num = (int)num;
293 break;
294 case BIO_CTRL_INFO:
295 ret = (long)bm->length;
296 if (ptr != NULL) {
297 pptr = (char **)ptr;
298 *pptr = (char *)(bm->data);
299 }
300 break;
301 case BIO_C_SET_BUF_MEM:
302 mem_buf_free(b);
303 b->shutdown = (int)num;
304 bbm->buf = ptr;
305 *bbm->readp = *bbm->buf;
306 break;
307 case BIO_C_GET_BUF_MEM_PTR:
308 if (ptr != NULL) {
309 if (!(b->flags & BIO_FLAGS_MEM_RDONLY))
310 mem_buf_sync(b);
311 bm = bbm->buf;
312 pptr = (char **)ptr;
313 *pptr = (char *)bm;
314 }
315 break;
316 case BIO_CTRL_GET_CLOSE:
317 ret = (long)b->shutdown;
318 break;
319 case BIO_CTRL_SET_CLOSE:
320 b->shutdown = (int)num;
321 break;
322 case BIO_CTRL_WPENDING:
323 ret = 0L;
324 break;
325 case BIO_CTRL_PENDING:
326 ret = (long)bm->length;
327 break;
328 case BIO_CTRL_DUP:
329 case BIO_CTRL_FLUSH:
330 ret = 1;
331 break;
332 case BIO_CTRL_PUSH:
333 case BIO_CTRL_POP:
334 default:
335 ret = 0;
336 break;
337 }
338 return ret;
339 }
340
mem_gets(BIO * bp,char * buf,int size)341 static int mem_gets(BIO *bp, char *buf, int size)
342 {
343 int i, j;
344 int ret = -1;
345 char *p;
346 BIO_BUF_MEM *bbm = (BIO_BUF_MEM *)bp->ptr;
347 BUF_MEM *bm = bbm->readp;
348
349 if (bp->flags & BIO_FLAGS_MEM_RDONLY)
350 bm = bbm->buf;
351 BIO_clear_retry_flags(bp);
352 j = bm->length;
353 if ((size - 1) < j)
354 j = size - 1;
355 if (j <= 0) {
356 *buf = '\0';
357 return 0;
358 }
359 p = bm->data;
360 for (i = 0; i < j; i++) {
361 if (p[i] == '\n') {
362 i++;
363 break;
364 }
365 }
366
367 /*
368 * i is now the max num of bytes to copy, either j or up to
369 * and including the first newline
370 */
371
372 i = mem_read(bp, buf, i);
373 if (i > 0)
374 buf[i] = '\0';
375 ret = i;
376 return ret;
377 }
378
mem_puts(BIO * bp,const char * str)379 static int mem_puts(BIO *bp, const char *str)
380 {
381 int n, ret;
382
383 n = strlen(str);
384 ret = mem_write(bp, str, n);
385 /* memory semantics is that it will always work */
386 return ret;
387 }
388
