1/*
2 * Copyright 1995-2016 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 buffer_write(BIO *h, const char *buf, int num);
16static int buffer_read(BIO *h, char *buf, int size);
17static int buffer_puts(BIO *h, const char *str);
18static int buffer_gets(BIO *h, char *str, int size);
19static long buffer_ctrl(BIO *h, int cmd, long arg1, void *arg2);
20static int buffer_new(BIO *h);
21static int buffer_free(BIO *data);
22static long buffer_callback_ctrl(BIO *h, int cmd, BIO_info_cb *fp);
23#define DEFAULT_BUFFER_SIZE 4096
24
25static const BIO_METHOD methods_buffer = {
26 BIO_TYPE_BUFFER,
27 "buffer",
28 /* TODO: Convert to new style write function */
29 bwrite_conv,
30 buffer_write,
31 /* TODO: Convert to new style read function */
32 bread_conv,
33 buffer_read,
34 buffer_puts,
35 buffer_gets,
36 buffer_ctrl,
37 buffer_new,
38 buffer_free,
39 buffer_callback_ctrl,
40};
41
42const BIO_METHOD *BIO_f_buffer(void)
43{
44 return &methods_buffer;
45}
46
47static int buffer_new(BIO *bi)
48{
49 BIO_F_BUFFER_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx));
50
51 if (ctx == NULL)
52 return 0;
53 ctx->ibuf_size = DEFAULT_BUFFER_SIZE;
54 ctx->ibuf = OPENSSL_malloc(DEFAULT_BUFFER_SIZE);
55 if (ctx->ibuf == NULL) {
56 OPENSSL_free(ctx);
57 return 0;
58 }
59 ctx->obuf_size = DEFAULT_BUFFER_SIZE;
60 ctx->obuf = OPENSSL_malloc(DEFAULT_BUFFER_SIZE);
61 if (ctx->obuf == NULL) {
62 OPENSSL_free(ctx->ibuf);
63 OPENSSL_free(ctx);
64 return 0;
65 }
66
67 bi->init = 1;
68 bi->ptr = (char *)ctx;
69 bi->flags = 0;
70 return 1;
71}
72
73static int buffer_free(BIO *a)
74{
75 BIO_F_BUFFER_CTX *b;
76
77 if (a == NULL)
78 return 0;
79 b = (BIO_F_BUFFER_CTX *)a->ptr;
80 OPENSSL_free(b->ibuf);
81 OPENSSL_free(b->obuf);
82 OPENSSL_free(a->ptr);
83 a->ptr = NULL;
84 a->init = 0;
85 a->flags = 0;
86 return 1;
87}
88
89static int buffer_read(BIO *b, char *out, int outl)
90{
91 int i, num = 0;
92 BIO_F_BUFFER_CTX *ctx;
93
94 if (out == NULL)
95 return 0;
96 ctx = (BIO_F_BUFFER_CTX *)b->ptr;
97
98 if ((ctx == NULL) || (b->next_bio == NULL))
99 return 0;
100 num = 0;
101 BIO_clear_retry_flags(b);
102
103 start:
104 i = ctx->ibuf_len;
105 /* If there is stuff left over, grab it */
106 if (i != 0) {
107 if (i > outl)
108 i = outl;
109 memcpy(out, &(ctx->ibuf[ctx->ibuf_off]), i);
110 ctx->ibuf_off += i;
111 ctx->ibuf_len -= i;
112 num += i;
113 if (outl == i)
114 return num;
115 outl -= i;
116 out += i;
117 }
118
119 /*
120 * We may have done a partial read. try to do more. We have nothing in
121 * the buffer. If we get an error and have read some data, just return it
122 * and let them retry to get the error again. copy direct to parent
123 * address space
124 */
125 if (outl > ctx->ibuf_size) {
126 for (;;) {
127 i = BIO_read(b->next_bio, out, outl);
128 if (i <= 0) {
129 BIO_copy_next_retry(b);
130 if (i < 0)
131 return ((num > 0) ? num : i);
132 if (i == 0)
133 return num;
134 }
135 num += i;
136 if (outl == i)
137 return num;
138 out += i;
139 outl -= i;
140 }
141 }
142 /* else */
143
144 /* we are going to be doing some buffering */
145 i = BIO_read(b->next_bio, ctx->ibuf, ctx->ibuf_size);
146 if (i <= 0) {
147 BIO_copy_next_retry(b);
148 if (i < 0)
149 return ((num > 0) ? num : i);
150 if (i == 0)
151 return num;
152 }
153 ctx->ibuf_off = 0;
154 ctx->ibuf_len = i;
155
156 /* Lets re-read using ourselves :-) */
157 goto start;
158}
159
160static int buffer_write(BIO *b, const char *in, int inl)
161{
162 int i, num = 0;
163 BIO_F_BUFFER_CTX *ctx;
164
165 if ((in == NULL) || (inl <= 0))
166 return 0;
167 ctx = (BIO_F_BUFFER_CTX *)b->ptr;
168 if ((ctx == NULL) || (b->next_bio == NULL))
169 return 0;
170
171 BIO_clear_retry_flags(b);
172 start:
173 i = ctx->obuf_size - (ctx->obuf_len + ctx->obuf_off);
174 /* add to buffer and return */
175 if (i >= inl) {
176 memcpy(&(ctx->obuf[ctx->obuf_off + ctx->obuf_len]), in, inl);
177 ctx->obuf_len += inl;
178 return (num + inl);
179 }
180 /* else */
181 /* stuff already in buffer, so add to it first, then flush */
182 if (ctx->obuf_len != 0) {
183 if (i > 0) { /* lets fill it up if we can */
184 memcpy(&(ctx->obuf[ctx->obuf_off + ctx->obuf_len]), in, i);
185 in += i;
186 inl -= i;
187 num += i;
188 ctx->obuf_len += i;
189 }
190 /* we now have a full buffer needing flushing */
191 for (;;) {
192 i = BIO_write(b->next_bio, &(ctx->obuf[ctx->obuf_off]),
193 ctx->obuf_len);
194 if (i <= 0) {
195 BIO_copy_next_retry(b);
196
197 if (i < 0)
198 return ((num > 0) ? num : i);
199 if (i == 0)
200 return num;
201 }
202 ctx->obuf_off += i;
203 ctx->obuf_len -= i;
204 if (ctx->obuf_len == 0)
205 break;
206 }
207 }
208 /*
209 * we only get here if the buffer has been flushed and we still have
210 * stuff to write
211 */
212 ctx->obuf_off = 0;
213
214 /* we now have inl bytes to write */
215 while (inl >= ctx->obuf_size) {
216 i = BIO_write(b->next_bio, in, inl);
217 if (i <= 0) {
218 BIO_copy_next_retry(b);
219 if (i < 0)
220 return ((num > 0) ? num : i);
221 if (i == 0)
222 return num;
223 }
224 num += i;
225 in += i;
226 inl -= i;
227 if (inl == 0)
228 return num;
229 }
230
231 /*
232 * copy the rest into the buffer since we have only a small amount left
233 */
234 goto start;
235}
236
237static long buffer_ctrl(BIO *b, int cmd, long num, void *ptr)
238{
239 BIO *dbio;
240 BIO_F_BUFFER_CTX *ctx;
241 long ret = 1;
242 char *p1, *p2;
243 int r, i, *ip;
244 int ibs, obs;
245
246 ctx = (BIO_F_BUFFER_CTX *)b->ptr;
247
248 switch (cmd) {
249 case BIO_CTRL_RESET:
250 ctx->ibuf_off = 0;
251 ctx->ibuf_len = 0;
252 ctx->obuf_off = 0;
253 ctx->obuf_len = 0;
254 if (b->next_bio == NULL)
255 return 0;
256 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
257 break;
258 case BIO_CTRL_EOF:
259 if (ctx->ibuf_len > 0)
260 return 0;
261 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
262 break;
263 case BIO_CTRL_INFO:
264 ret = (long)ctx->obuf_len;
265 break;
266 case BIO_C_GET_BUFF_NUM_LINES:
267 ret = 0;
268 p1 = ctx->ibuf;
269 for (i = 0; i < ctx->ibuf_len; i++) {
270 if (p1[ctx->ibuf_off + i] == '\n')
271 ret++;
272 }
273 break;
274 case BIO_CTRL_WPENDING:
275 ret = (long)ctx->obuf_len;
276 if (ret == 0) {
277 if (b->next_bio == NULL)
278 return 0;
279 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
280 }
281 break;
282 case BIO_CTRL_PENDING:
283 ret = (long)ctx->ibuf_len;
284 if (ret == 0) {
285 if (b->next_bio == NULL)
286 return 0;
287 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
288 }
289 break;
290 case BIO_C_SET_BUFF_READ_DATA:
291 if (num > ctx->ibuf_size) {
292 p1 = OPENSSL_malloc((int)num);
293 if (p1 == NULL)
294 goto malloc_error;
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 p1 = OPENSSL_malloc((int)num);
322 if (p1 == NULL)
323 goto malloc_error;
324 }
325 if ((obs > DEFAULT_BUFFER_SIZE) && (obs != ctx->obuf_size)) {
326 p2 = OPENSSL_malloc((int)num);
327 if (p2 == NULL) {
328 if (p1 != ctx->ibuf)
329 OPENSSL_free(p1);
330 goto malloc_error;
331 }
332 }
333 if (ctx->ibuf != p1) {
334 OPENSSL_free(ctx->ibuf);
335 ctx->ibuf = p1;
336 ctx->ibuf_off = 0;
337 ctx->ibuf_len = 0;
338 ctx->ibuf_size = ibs;
339 }
340 if (ctx->obuf != p2) {
341 OPENSSL_free(ctx->obuf);
342 ctx->obuf = p2;
343 ctx->obuf_off = 0;
344 ctx->obuf_len = 0;
345 ctx->obuf_size = obs;
346 }
347 break;
348 case BIO_C_DO_STATE_MACHINE:
349 if (b->next_bio == NULL)
350 return 0;
351 BIO_clear_retry_flags(b);
352 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
353 BIO_copy_next_retry(b);
354 break;
355
356 case BIO_CTRL_FLUSH:
357 if (b->next_bio == NULL)
358 return 0;
359 if (ctx->obuf_len <= 0) {
360 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
361 break;
362 }
363
364 for (;;) {
365 BIO_clear_retry_flags(b);
366 if (ctx->obuf_len > 0) {
367 r = BIO_write(b->next_bio,
368 &(ctx->obuf[ctx->obuf_off]), ctx->obuf_len);
369 BIO_copy_next_retry(b);
370 if (r <= 0)
371 return (long)r;
372 ctx->obuf_off += r;
373 ctx->obuf_len -= r;
374 } else {
375 ctx->obuf_len = 0;
376 ctx->obuf_off = 0;
377 break;
378 }
379 }
380 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
381 break;
382 case BIO_CTRL_DUP:
383 dbio = (BIO *)ptr;
384 if (!BIO_set_read_buffer_size(dbio, ctx->ibuf_size) ||
385 !BIO_set_write_buffer_size(dbio, ctx->obuf_size))
386 ret = 0;
387 break;
388 case BIO_CTRL_PEEK:
389 /* Ensure there's stuff in the input buffer */
390 {
391 char fake_buf[1];
392 (void)buffer_read(b, fake_buf, 0);
393 }
394 if (num > ctx->ibuf_len)
395 num = ctx->ibuf_len;
396 memcpy(ptr, &(ctx->ibuf[ctx->ibuf_off]), num);
397 ret = num;
398 break;
399 default:
400 if (b->next_bio == NULL)
401 return 0;
402 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
403 break;
404 }
405 return ret;
406 malloc_error:
407 BIOerr(BIO_F_BUFFER_CTRL, ERR_R_MALLOC_FAILURE);
408 return 0;
409}
410
411static long buffer_callback_ctrl(BIO *b, int cmd, BIO_info_cb *fp)
412{
413 long ret = 1;
414
415 if (b->next_bio == NULL)
416 return 0;
417 switch (cmd) {
418 default:
419 ret = BIO_callback_ctrl(b->next_bio, cmd, fp);
420 break;
421 }
422 return ret;
423}
424
425static int buffer_gets(BIO *b, char *buf, int size)
426{
427 BIO_F_BUFFER_CTX *ctx;
428 int num = 0, i, flag;
429 char *p;
430
431 ctx = (BIO_F_BUFFER_CTX *)b->ptr;
432 size--; /* reserve space for a '\0' */
433 BIO_clear_retry_flags(b);
434
435 for (;;) {
436 if (ctx->ibuf_len > 0) {
437 p = &(ctx->ibuf[ctx->ibuf_off]);
438 flag = 0;
439 for (i = 0; (i < ctx->ibuf_len) && (i < size); i++) {
440 *(buf++) = p[i];
441 if (p[i] == '\n') {
442 flag = 1;
443 i++;
444 break;
445 }
446 }
447 num += i;
448 size -= i;
449 ctx->ibuf_len -= i;
450 ctx->ibuf_off += i;
451 if (flag || size == 0) {
452 *buf = '\0';
453 return num;
454 }
455 } else { /* read another chunk */
456
457 i = BIO_read(b->next_bio, ctx->ibuf, ctx->ibuf_size);
458 if (i <= 0) {
459 BIO_copy_next_retry(b);
460 *buf = '\0';
461 if (i < 0)
462 return ((num > 0) ? num : i);
463 if (i == 0)
464 return num;
465 }
466 ctx->ibuf_len = i;
467 ctx->ibuf_off = 0;
468 }
469 }
470}
471
472static int buffer_puts(BIO *b, const char *str)
473{
474 return buffer_write(b, str, strlen(str));
475}
476