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 buffer_write(BIO *h, const char *buf, int num);
16 static int buffer_read(BIO *h, char *buf, int size);
17 static int buffer_puts(BIO *h, const char *str);
18 static int buffer_gets(BIO *h, char *str, int size);
19 static long buffer_ctrl(BIO *h, int cmd, long arg1, void *arg2);
20 static int buffer_new(BIO *h);
21 static int buffer_free(BIO *data);
22 static long buffer_callback_ctrl(BIO *h, int cmd, BIO_info_cb *fp);
23 #define DEFAULT_BUFFER_SIZE 4096
24
25 static const BIO_METHOD methods_buffer = {
26 BIO_TYPE_BUFFER,
27 "buffer",
28 bwrite_conv,
29 buffer_write,
30 bread_conv,
31 buffer_read,
32 buffer_puts,
33 buffer_gets,
34 buffer_ctrl,
35 buffer_new,
36 buffer_free,
37 buffer_callback_ctrl,
38 };
39
BIO_f_buffer(void)40 const BIO_METHOD *BIO_f_buffer(void)
41 {
42 return &methods_buffer;
43 }
44
buffer_new(BIO * bi)45 static int buffer_new(BIO *bi)
46 {
47 BIO_F_BUFFER_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx));
48
49 if (ctx == NULL)
50 return 0;
51 ctx->ibuf_size = DEFAULT_BUFFER_SIZE;
52 ctx->ibuf = OPENSSL_malloc(DEFAULT_BUFFER_SIZE);
53 if (ctx->ibuf == NULL) {
54 OPENSSL_free(ctx);
55 return 0;
56 }
57 ctx->obuf_size = DEFAULT_BUFFER_SIZE;
58 ctx->obuf = OPENSSL_malloc(DEFAULT_BUFFER_SIZE);
59 if (ctx->obuf == NULL) {
60 OPENSSL_free(ctx->ibuf);
61 OPENSSL_free(ctx);
62 return 0;
63 }
64
65 bi->init = 1;
66 bi->ptr = (char *)ctx;
67 bi->flags = 0;
68 return 1;
69 }
70
buffer_free(BIO * a)71 static int buffer_free(BIO *a)
72 {
73 BIO_F_BUFFER_CTX *b;
74
75 if (a == NULL)
76 return 0;
77 b = (BIO_F_BUFFER_CTX *)a->ptr;
78 OPENSSL_free(b->ibuf);
79 OPENSSL_free(b->obuf);
80 OPENSSL_free(a->ptr);
81 a->ptr = NULL;
82 a->init = 0;
83 a->flags = 0;
84 return 1;
85 }
86
buffer_read(BIO * b,char * out,int outl)87 static int buffer_read(BIO *b, char *out, int outl)
88 {
89 int i, num = 0;
90 BIO_F_BUFFER_CTX *ctx;
91
92 if (out == NULL)
93 return 0;
94 ctx = (BIO_F_BUFFER_CTX *)b->ptr;
95
96 if ((ctx == NULL) || (b->next_bio == NULL))
97 return 0;
98 num = 0;
99 BIO_clear_retry_flags(b);
100
101 start:
102 i = ctx->ibuf_len;
103 /* If there is stuff left over, grab it */
104 if (i != 0) {
105 if (i > outl)
106 i = outl;
107 memcpy(out, &(ctx->ibuf[ctx->ibuf_off]), i);
108 ctx->ibuf_off += i;
109 ctx->ibuf_len -= i;
110 num += i;
111 if (outl == i)
112 return num;
113 outl -= i;
114 out += i;
115 }
116
117 /*
118 * We may have done a partial read. try to do more. We have nothing in
119 * the buffer. If we get an error and have read some data, just return it
120 * and let them retry to get the error again. copy direct to parent
121 * address space
122 */
123 if (outl > ctx->ibuf_size) {
124 for (;;) {
125 i = BIO_read(b->next_bio, out, outl);
126 if (i <= 0) {
127 BIO_copy_next_retry(b);
128 if (i < 0)
129 return ((num > 0) ? num : i);
130 if (i == 0)
131 return num;
132 }
133 num += i;
134 if (outl == i)
135 return num;
136 out += i;
137 outl -= i;
138 }
139 }
140 /* else */
141
142 /* we are going to be doing some buffering */
143 i = BIO_read(b->next_bio, ctx->ibuf, ctx->ibuf_size);
144 if (i <= 0) {
145 BIO_copy_next_retry(b);
146 if (i < 0)
147 return ((num > 0) ? num : i);
148 if (i == 0)
149 return num;
150 }
151 ctx->ibuf_off = 0;
152 ctx->ibuf_len = i;
153
154 /* Lets re-read using ourselves :-) */
155 goto start;
156 }
157
buffer_write(BIO * b,const char * in,int inl)158 static int buffer_write(BIO *b, const char *in, int inl)
159 {
160 int i, num = 0;
161 BIO_F_BUFFER_CTX *ctx;
162
163 if ((in == NULL) || (inl <= 0))
164 return 0;
165 ctx = (BIO_F_BUFFER_CTX *)b->ptr;
166 if ((ctx == NULL) || (b->next_bio == NULL))
167 return 0;
168
169 BIO_clear_retry_flags(b);
170 start:
171 i = ctx->obuf_size - (ctx->obuf_len + ctx->obuf_off);
172 /* add to buffer and return */
173 if (i >= inl) {
174 memcpy(&(ctx->obuf[ctx->obuf_off + ctx->obuf_len]), in, inl);
175 ctx->obuf_len += inl;
176 return (num + inl);
177 }
178 /* else */
179 /* stuff already in buffer, so add to it first, then flush */
180 if (ctx->obuf_len != 0) {
181 if (i > 0) { /* lets fill it up if we can */
182 memcpy(&(ctx->obuf[ctx->obuf_off + ctx->obuf_len]), in, i);
183 in += i;
184 inl -= i;
185 num += i;
186 ctx->obuf_len += i;
187 }
188 /* we now have a full buffer needing flushing */
189 for (;;) {
190 i = BIO_write(b->next_bio, &(ctx->obuf[ctx->obuf_off]),
191 ctx->obuf_len);
192 if (i <= 0) {
193 BIO_copy_next_retry(b);
194
195 if (i < 0)
196 return ((num > 0) ? num : i);
197 if (i == 0)
198 return num;
199 }
200 ctx->obuf_off += i;
201 ctx->obuf_len -= i;
202 if (ctx->obuf_len == 0)
203 break;
204 }
205 }
206 /*
207 * we only get here if the buffer has been flushed and we still have
208 * stuff to write
209 */
210 ctx->obuf_off = 0;
211
212 /* we now have inl bytes to write */
213 while (inl >= ctx->obuf_size) {
214 i = BIO_write(b->next_bio, in, inl);
215 if (i <= 0) {
216 BIO_copy_next_retry(b);
217 if (i < 0)
218 return ((num > 0) ? num : i);
219 if (i == 0)
220 return num;
221 }
222 num += i;
223 in += i;
224 inl -= i;
225 if (inl == 0)
226 return num;
227 }
228
229 /*
230 * copy the rest into the buffer since we have only a small amount left
231 */
232 goto start;
233 }
234
buffer_ctrl(BIO * b,int cmd,long num,void * ptr)235 static long buffer_ctrl(BIO *b, int cmd, long num, void *ptr)
236 {
237 BIO *dbio;
238 BIO_F_BUFFER_CTX *ctx;
239 long ret = 1;
240 char *p1, *p2;
241 int r, i, *ip;
242 int ibs, obs;
243
244 ctx = (BIO_F_BUFFER_CTX *)b->ptr;
245
246 switch (cmd) {
247 case BIO_CTRL_RESET:
248 ctx->ibuf_off = 0;
249 ctx->ibuf_len = 0;
250 ctx->obuf_off = 0;
251 ctx->obuf_len = 0;
252 if (b->next_bio == NULL)
253 return 0;
254 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
255 break;
256 case BIO_CTRL_EOF:
257 if (ctx->ibuf_len > 0)
258 return 0;
259 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
260 break;
261 case BIO_CTRL_INFO:
262 ret = (long)ctx->obuf_len;
263 break;
264 case BIO_C_GET_BUFF_NUM_LINES:
265 ret = 0;
266 p1 = ctx->ibuf;
267 for (i = 0; i < ctx->ibuf_len; i++) {
268 if (p1[ctx->ibuf_off + i] == '\n')
269 ret++;
270 }
271 break;
272 case BIO_CTRL_WPENDING:
273 ret = (long)ctx->obuf_len;
274 if (ret == 0) {
275 if (b->next_bio == NULL)
276 return 0;
277 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
278 }
279 break;
280 case BIO_CTRL_PENDING:
281 ret = (long)ctx->ibuf_len;
282 if (ret == 0) {
283 if (b->next_bio == NULL)
284 return 0;
285 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
286 }
287 break;
288 case BIO_C_SET_BUFF_READ_DATA:
289 if (num > ctx->ibuf_size) {
290 if (num <= 0)
291 return 0;
292 p1 = OPENSSL_malloc((size_t)num);
293 if (p1 == NULL)
294 return 0;
295 OPENSSL_free(ctx->ibuf);
296 ctx->ibuf = p1;
297 }
298 ctx->ibuf_off = 0;
299 ctx->ibuf_len = (int)num;
300 memcpy(ctx->ibuf, ptr, (int)num);
301 ret = 1;
302 break;
303 case BIO_C_SET_BUFF_SIZE:
304 if (ptr != NULL) {
305 ip = (int *)ptr;
306 if (*ip == 0) {
307 ibs = (int)num;
308 obs = ctx->obuf_size;
309 } else { /* if (*ip == 1) */
310
311 ibs = ctx->ibuf_size;
312 obs = (int)num;
313 }
314 } else {
315 ibs = (int)num;
316 obs = (int)num;
317 }
318 p1 = ctx->ibuf;
319 p2 = ctx->obuf;
320 if ((ibs > DEFAULT_BUFFER_SIZE) && (ibs != ctx->ibuf_size)) {
321 if (num <= 0)
322 return 0;
323 p1 = OPENSSL_malloc((size_t)num);
324 if (p1 == NULL)
325 return 0;
326 }
327 if ((obs > DEFAULT_BUFFER_SIZE) && (obs != ctx->obuf_size)) {
328 p2 = OPENSSL_malloc((size_t)num);
329 if (p2 == NULL) {
330 if (p1 != ctx->ibuf)
331 OPENSSL_free(p1);
332 return 0;
333 }
334 }
335 if (ctx->ibuf != p1) {
336 OPENSSL_free(ctx->ibuf);
337 ctx->ibuf = p1;
338 ctx->ibuf_off = 0;
339 ctx->ibuf_len = 0;
340 ctx->ibuf_size = ibs;
341 }
342 if (ctx->obuf != p2) {
343 OPENSSL_free(ctx->obuf);
344 ctx->obuf = p2;
345 ctx->obuf_off = 0;
346 ctx->obuf_len = 0;
347 ctx->obuf_size = obs;
348 }
349 break;
350 case BIO_C_DO_STATE_MACHINE:
351 if (b->next_bio == NULL)
352 return 0;
353 BIO_clear_retry_flags(b);
354 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
355 BIO_copy_next_retry(b);
356 break;
357
358 case BIO_CTRL_FLUSH:
359 if (b->next_bio == NULL)
360 return 0;
361 if (ctx->obuf_len <= 0) {
362 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
363 BIO_copy_next_retry(b);
364 break;
365 }
366
367 for (;;) {
368 BIO_clear_retry_flags(b);
369 if (ctx->obuf_len > 0) {
370 r = BIO_write(b->next_bio,
371 &(ctx->obuf[ctx->obuf_off]), ctx->obuf_len);
372 BIO_copy_next_retry(b);
373 if (r <= 0)
374 return (long)r;
375 ctx->obuf_off += r;
376 ctx->obuf_len -= r;
377 } else {
378 ctx->obuf_len = 0;
379 ctx->obuf_off = 0;
380 break;
381 }
382 }
383 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
384 BIO_copy_next_retry(b);
385 break;
386 case BIO_CTRL_DUP:
387 dbio = (BIO *)ptr;
388 if (BIO_set_read_buffer_size(dbio, ctx->ibuf_size) <= 0 ||
389 BIO_set_write_buffer_size(dbio, ctx->obuf_size) <= 0)
390 ret = 0;
391 break;
392 case BIO_CTRL_PEEK:
393 /* Ensure there's stuff in the input buffer */
394 {
395 char fake_buf[1];
396 (void)buffer_read(b, fake_buf, 0);
397 }
398 if (num > ctx->ibuf_len)
399 num = ctx->ibuf_len;
400 memcpy(ptr, &(ctx->ibuf[ctx->ibuf_off]), num);
401 ret = num;
402 break;
403 default:
404 if (b->next_bio == NULL)
405 return 0;
406 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
407 break;
408 }
409 return ret;
410 }
411
buffer_callback_ctrl(BIO * b,int cmd,BIO_info_cb * fp)412 static long buffer_callback_ctrl(BIO *b, int cmd, BIO_info_cb *fp)
413 {
414 if (b->next_bio == NULL)
415 return 0;
416 return BIO_callback_ctrl(b->next_bio, cmd, fp);
417 }
418
buffer_gets(BIO * b,char * buf,int size)419 static int buffer_gets(BIO *b, char *buf, int size)
420 {
421 BIO_F_BUFFER_CTX *ctx;
422 int num = 0, i, flag;
423 char *p;
424
425 ctx = (BIO_F_BUFFER_CTX *)b->ptr;
426 size--; /* reserve space for a '\0' */
427 BIO_clear_retry_flags(b);
428
429 for (;;) {
430 if (ctx->ibuf_len > 0) {
431 p = &(ctx->ibuf[ctx->ibuf_off]);
432 flag = 0;
433 for (i = 0; (i < ctx->ibuf_len) && (i < size); i++) {
434 *(buf++) = p[i];
435 if (p[i] == '\n') {
436 flag = 1;
437 i++;
438 break;
439 }
440 }
441 num += i;
442 size -= i;
443 ctx->ibuf_len -= i;
444 ctx->ibuf_off += i;
445 if (flag || size == 0) {
446 *buf = '\0';
447 return num;
448 }
449 } else { /* read another chunk */
450
451 i = BIO_read(b->next_bio, ctx->ibuf, ctx->ibuf_size);
452 if (i <= 0) {
453 BIO_copy_next_retry(b);
454 *buf = '\0';
455 if (i < 0)
456 return ((num > 0) ? num : i);
457 if (i == 0)
458 return num;
459 }
460 ctx->ibuf_len = i;
461 ctx->ibuf_off = 0;
462 }
463 }
464 }
465
buffer_puts(BIO * b,const char * str)466 static int buffer_puts(BIO *b, const char *str)
467 {
468 return buffer_write(b, str, strlen(str));
469 }
470
