xref: /openbsd-src/lib/libssl/bio_ssl.c (revision 3374c67d44f9b75b98444cbf63020f777792342e)
1 /* $OpenBSD: bio_ssl.c,v 1.37 2022/11/26 16:08:55 tb Exp $ */
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 <errno.h>
60 #include <stdio.h>
61 #include <stdlib.h>
62 #include <string.h>
63 
64 #include <openssl/bio.h>
65 #include <openssl/crypto.h>
66 #include <openssl/err.h>
67 #include <openssl/ssl.h>
68 
69 #include "bio_local.h"
70 #include "ssl_local.h"
71 
72 static int ssl_write(BIO *h, const char *buf, int num);
73 static int ssl_read(BIO *h, char *buf, int size);
74 static int ssl_puts(BIO *h, const char *str);
75 static long ssl_ctrl(BIO *h, int cmd, long arg1, void *arg2);
76 static int ssl_new(BIO *h);
77 static int ssl_free(BIO *data);
78 static long ssl_callback_ctrl(BIO *h, int cmd, BIO_info_cb *fp);
79 typedef struct bio_ssl_st {
80 	SSL *ssl; /* The ssl handle :-) */
81 	/* re-negotiate every time the total number of bytes is this size */
82 	int num_renegotiates;
83 	unsigned long renegotiate_count;
84 	unsigned long byte_count;
85 	unsigned long renegotiate_timeout;
86 	time_t last_time;
87 } BIO_SSL;
88 
89 static const BIO_METHOD methods_sslp = {
90 	.type = BIO_TYPE_SSL,
91 	.name = "ssl",
92 	.bwrite = ssl_write,
93 	.bread = ssl_read,
94 	.bputs = ssl_puts,
95 	.ctrl = ssl_ctrl,
96 	.create = ssl_new,
97 	.destroy = ssl_free,
98 	.callback_ctrl = ssl_callback_ctrl,
99 };
100 
101 const BIO_METHOD *
102 BIO_f_ssl(void)
103 {
104 	return (&methods_sslp);
105 }
106 LSSL_ALIAS(BIO_f_ssl)
107 
108 static int
109 ssl_new(BIO *bi)
110 {
111 	BIO_SSL *bs;
112 
113 	bs = calloc(1, sizeof(BIO_SSL));
114 	if (bs == NULL) {
115 		SSLerrorx(ERR_R_MALLOC_FAILURE);
116 		return (0);
117 	}
118 	bi->init = 0;
119 	bi->ptr = (char *)bs;
120 	bi->flags = 0;
121 	return (1);
122 }
123 
124 static int
125 ssl_free(BIO *a)
126 {
127 	BIO_SSL *bs;
128 
129 	if (a == NULL)
130 		return (0);
131 	bs = (BIO_SSL *)a->ptr;
132 	if (bs->ssl != NULL)
133 		SSL_shutdown(bs->ssl);
134 	if (a->shutdown) {
135 		if (a->init && (bs->ssl != NULL))
136 			SSL_free(bs->ssl);
137 		a->init = 0;
138 		a->flags = 0;
139 	}
140 	free(a->ptr);
141 	return (1);
142 }
143 
144 static int
145 ssl_read(BIO *b, char *out, int outl)
146 {
147 	int ret = 1;
148 	BIO_SSL *sb;
149 	SSL *ssl;
150 	int retry_reason = 0;
151 	int r = 0;
152 
153 	if (out == NULL)
154 		return (0);
155 	sb = (BIO_SSL *)b->ptr;
156 	ssl = sb->ssl;
157 
158 	BIO_clear_retry_flags(b);
159 
160 	ret = SSL_read(ssl, out, outl);
161 
162 	switch (SSL_get_error(ssl, ret)) {
163 	case SSL_ERROR_NONE:
164 		if (ret <= 0)
165 			break;
166 		if (sb->renegotiate_count > 0) {
167 			sb->byte_count += ret;
168 			if (sb->byte_count > sb->renegotiate_count) {
169 				sb->byte_count = 0;
170 				sb->num_renegotiates++;
171 				SSL_renegotiate(ssl);
172 				r = 1;
173 			}
174 		}
175 		if ((sb->renegotiate_timeout > 0) && (!r)) {
176 			time_t tm;
177 
178 			tm = time(NULL);
179 			if (tm > sb->last_time + sb->renegotiate_timeout) {
180 				sb->last_time = tm;
181 				sb->num_renegotiates++;
182 				SSL_renegotiate(ssl);
183 			}
184 		}
185 
186 		break;
187 	case SSL_ERROR_WANT_READ:
188 		BIO_set_retry_read(b);
189 		break;
190 	case SSL_ERROR_WANT_WRITE:
191 		BIO_set_retry_write(b);
192 		break;
193 	case SSL_ERROR_WANT_X509_LOOKUP:
194 		BIO_set_retry_special(b);
195 		retry_reason = BIO_RR_SSL_X509_LOOKUP;
196 		break;
197 	case SSL_ERROR_WANT_ACCEPT:
198 		BIO_set_retry_special(b);
199 		retry_reason = BIO_RR_ACCEPT;
200 		break;
201 	case SSL_ERROR_WANT_CONNECT:
202 		BIO_set_retry_special(b);
203 		retry_reason = BIO_RR_CONNECT;
204 		break;
205 	case SSL_ERROR_SYSCALL:
206 	case SSL_ERROR_SSL:
207 	case SSL_ERROR_ZERO_RETURN:
208 	default:
209 		break;
210 	}
211 
212 	b->retry_reason = retry_reason;
213 	return (ret);
214 }
215 
216 static int
217 ssl_write(BIO *b, const char *out, int outl)
218 {
219 	int ret, r = 0;
220 	int retry_reason = 0;
221 	SSL *ssl;
222 	BIO_SSL *bs;
223 
224 	if (out == NULL)
225 		return (0);
226 	bs = (BIO_SSL *)b->ptr;
227 	ssl = bs->ssl;
228 
229 	BIO_clear_retry_flags(b);
230 
231 /*	ret=SSL_do_handshake(ssl);
232 	if (ret > 0) */
233 		ret = SSL_write(ssl, out, outl);
234 
235 	switch (SSL_get_error(ssl, ret)) {
236 	case SSL_ERROR_NONE:
237 		if (ret <= 0)
238 			break;
239 		if (bs->renegotiate_count > 0) {
240 			bs->byte_count += ret;
241 			if (bs->byte_count > bs->renegotiate_count) {
242 				bs->byte_count = 0;
243 				bs->num_renegotiates++;
244 				SSL_renegotiate(ssl);
245 				r = 1;
246 			}
247 		}
248 		if ((bs->renegotiate_timeout > 0) && (!r)) {
249 			time_t tm;
250 
251 			tm = time(NULL);
252 			if (tm > bs->last_time + bs->renegotiate_timeout) {
253 				bs->last_time = tm;
254 				bs->num_renegotiates++;
255 				SSL_renegotiate(ssl);
256 			}
257 		}
258 		break;
259 	case SSL_ERROR_WANT_WRITE:
260 		BIO_set_retry_write(b);
261 		break;
262 	case SSL_ERROR_WANT_READ:
263 		BIO_set_retry_read(b);
264 		break;
265 	case SSL_ERROR_WANT_X509_LOOKUP:
266 		BIO_set_retry_special(b);
267 		retry_reason = BIO_RR_SSL_X509_LOOKUP;
268 		break;
269 	case SSL_ERROR_WANT_CONNECT:
270 		BIO_set_retry_special(b);
271 		retry_reason = BIO_RR_CONNECT;
272 	case SSL_ERROR_SYSCALL:
273 	case SSL_ERROR_SSL:
274 	default:
275 		break;
276 	}
277 
278 	b->retry_reason = retry_reason;
279 	return (ret);
280 }
281 
282 static long
283 ssl_ctrl(BIO *b, int cmd, long num, void *ptr)
284 {
285 	SSL **sslp, *ssl;
286 	BIO_SSL *bs;
287 	BIO *dbio, *bio;
288 	long ret = 1;
289 
290 	bs = (BIO_SSL *)b->ptr;
291 	ssl = bs->ssl;
292 	if ((ssl == NULL)  && (cmd != BIO_C_SET_SSL))
293 		return (0);
294 	switch (cmd) {
295 	case BIO_CTRL_RESET:
296 		SSL_shutdown(ssl);
297 
298 		if (ssl->handshake_func == ssl->method->ssl_connect)
299 			SSL_set_connect_state(ssl);
300 		else if (ssl->handshake_func == ssl->method->ssl_accept)
301 			SSL_set_accept_state(ssl);
302 
303 		SSL_clear(ssl);
304 
305 		if (b->next_bio != NULL)
306 			ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
307 		else if (ssl->rbio != NULL)
308 			ret = BIO_ctrl(ssl->rbio, cmd, num, ptr);
309 		else
310 			ret = 1;
311 		break;
312 	case BIO_CTRL_INFO:
313 		ret = 0;
314 		break;
315 	case BIO_C_SSL_MODE:
316 		if (num) /* client mode */
317 			SSL_set_connect_state(ssl);
318 		else
319 			SSL_set_accept_state(ssl);
320 		break;
321 	case BIO_C_SET_SSL_RENEGOTIATE_TIMEOUT:
322 		ret = bs->renegotiate_timeout;
323 		if (num < 60)
324 			num = 5;
325 		bs->renegotiate_timeout = (unsigned long)num;
326 		bs->last_time = time(NULL);
327 		break;
328 	case BIO_C_SET_SSL_RENEGOTIATE_BYTES:
329 		ret = bs->renegotiate_count;
330 		if ((long)num >=512)
331 			bs->renegotiate_count = (unsigned long)num;
332 		break;
333 	case BIO_C_GET_SSL_NUM_RENEGOTIATES:
334 		ret = bs->num_renegotiates;
335 		break;
336 	case BIO_C_SET_SSL:
337 		if (ssl != NULL) {
338 			ssl_free(b);
339 			if (!ssl_new(b))
340 				return 0;
341 		}
342 		b->shutdown = (int)num;
343 		ssl = (SSL *)ptr;
344 		((BIO_SSL *)b->ptr)->ssl = ssl;
345 		bio = SSL_get_rbio(ssl);
346 		if (bio != NULL) {
347 			if (b->next_bio != NULL)
348 				BIO_push(bio, b->next_bio);
349 			b->next_bio = bio;
350 			CRYPTO_add(&bio->references, 1, CRYPTO_LOCK_BIO);
351 		}
352 		b->init = 1;
353 		break;
354 	case BIO_C_GET_SSL:
355 		if (ptr != NULL) {
356 			sslp = (SSL **)ptr;
357 			*sslp = ssl;
358 		} else
359 			ret = 0;
360 		break;
361 	case BIO_CTRL_GET_CLOSE:
362 		ret = b->shutdown;
363 		break;
364 	case BIO_CTRL_SET_CLOSE:
365 		b->shutdown = (int)num;
366 		break;
367 	case BIO_CTRL_WPENDING:
368 		ret = BIO_ctrl(ssl->wbio, cmd, num, ptr);
369 		break;
370 	case BIO_CTRL_PENDING:
371 		ret = SSL_pending(ssl);
372 		if (ret == 0)
373 			ret = BIO_pending(ssl->rbio);
374 		break;
375 	case BIO_CTRL_FLUSH:
376 		BIO_clear_retry_flags(b);
377 		ret = BIO_ctrl(ssl->wbio, cmd, num, ptr);
378 		BIO_copy_next_retry(b);
379 		break;
380 	case BIO_CTRL_PUSH:
381 		if ((b->next_bio != NULL) && (b->next_bio != ssl->rbio)) {
382 			SSL_set_bio(ssl, b->next_bio, b->next_bio);
383 			CRYPTO_add(&b->next_bio->references, 1,
384 			    CRYPTO_LOCK_BIO);
385 		}
386 		break;
387 	case BIO_CTRL_POP:
388 		/* Only detach if we are the BIO explicitly being popped */
389 		if (b == ptr) {
390 			/* Shouldn't happen in practice because the
391 			 * rbio and wbio are the same when pushed.
392 			 */
393 			if (ssl->rbio != ssl->wbio)
394 				BIO_free_all(ssl->wbio);
395 			if (b->next_bio != NULL)
396 				CRYPTO_add(&b->next_bio->references, -1, CRYPTO_LOCK_BIO);
397 			ssl->wbio = NULL;
398 			ssl->rbio = NULL;
399 		}
400 		break;
401 	case BIO_C_DO_STATE_MACHINE:
402 		BIO_clear_retry_flags(b);
403 
404 		b->retry_reason = 0;
405 		ret = (int)SSL_do_handshake(ssl);
406 
407 		switch (SSL_get_error(ssl, (int)ret)) {
408 		case SSL_ERROR_WANT_READ:
409 			BIO_set_flags(b,
410 			    BIO_FLAGS_READ|BIO_FLAGS_SHOULD_RETRY);
411 			break;
412 		case SSL_ERROR_WANT_WRITE:
413 			BIO_set_flags(b,
414 			    BIO_FLAGS_WRITE|BIO_FLAGS_SHOULD_RETRY);
415 			break;
416 		case SSL_ERROR_WANT_CONNECT:
417 			BIO_set_flags(b,
418 			    BIO_FLAGS_IO_SPECIAL|BIO_FLAGS_SHOULD_RETRY);
419 			b->retry_reason = b->next_bio->retry_reason;
420 			break;
421 		default:
422 			break;
423 		}
424 		break;
425 	case BIO_CTRL_DUP:
426 		dbio = (BIO *)ptr;
427 		if (((BIO_SSL *)dbio->ptr)->ssl != NULL)
428 			SSL_free(((BIO_SSL *)dbio->ptr)->ssl);
429 		((BIO_SSL *)dbio->ptr)->ssl = SSL_dup(ssl);
430 		((BIO_SSL *)dbio->ptr)->renegotiate_count =
431 		    ((BIO_SSL *)b->ptr)->renegotiate_count;
432 		((BIO_SSL *)dbio->ptr)->byte_count =
433 		    ((BIO_SSL *)b->ptr)->byte_count;
434 		((BIO_SSL *)dbio->ptr)->renegotiate_timeout =
435 		    ((BIO_SSL *)b->ptr)->renegotiate_timeout;
436 		((BIO_SSL *)dbio->ptr)->last_time =
437 		    ((BIO_SSL *)b->ptr)->last_time;
438 		ret = (((BIO_SSL *)dbio->ptr)->ssl != NULL);
439 		break;
440 	case BIO_C_GET_FD:
441 		ret = BIO_ctrl(ssl->rbio, cmd, num, ptr);
442 		break;
443 	case BIO_CTRL_SET_CALLBACK:
444 		{
445 			ret = 0;
446 		}
447 		break;
448 	case BIO_CTRL_GET_CALLBACK:
449 		{
450 			void (**fptr)(const SSL *xssl, int type, int val);
451 
452 			fptr = (void (**)(const SSL *xssl, int type, int val))
453 			    ptr;
454 			*fptr = SSL_get_info_callback(ssl);
455 		}
456 		break;
457 	default:
458 		ret = BIO_ctrl(ssl->rbio, cmd, num, ptr);
459 		break;
460 	}
461 	return (ret);
462 }
463 
464 static long
465 ssl_callback_ctrl(BIO *b, int cmd, BIO_info_cb *fp)
466 {
467 	SSL *ssl;
468 	BIO_SSL *bs;
469 	long ret = 1;
470 
471 	bs = (BIO_SSL *)b->ptr;
472 	ssl = bs->ssl;
473 	switch (cmd) {
474 	case BIO_CTRL_SET_CALLBACK:
475 		{
476 		/* FIXME: setting this via a completely different prototype
477 		   seems like a crap idea */
478 			SSL_set_info_callback(ssl,
479 			    (void (*)(const SSL *, int, int))fp);
480 		}
481 		break;
482 	default:
483 		ret = BIO_callback_ctrl(ssl->rbio, cmd, fp);
484 		break;
485 	}
486 	return (ret);
487 }
488 
489 static int
490 ssl_puts(BIO *bp, const char *str)
491 {
492 	int n, ret;
493 
494 	n = strlen(str);
495 	ret = BIO_write(bp, str, n);
496 	return (ret);
497 }
498 
499 BIO *
500 BIO_new_buffer_ssl_connect(SSL_CTX *ctx)
501 {
502 	BIO *ret = NULL, *buf = NULL, *ssl = NULL;
503 
504 	if ((buf = BIO_new(BIO_f_buffer())) == NULL)
505 		goto err;
506 	if ((ssl = BIO_new_ssl_connect(ctx)) == NULL)
507 		goto err;
508 	if ((ret = BIO_push(buf, ssl)) == NULL)
509 		goto err;
510 	return (ret);
511 
512  err:
513 	BIO_free(buf);
514 	BIO_free(ssl);
515 	return (NULL);
516 }
517 
518 BIO *
519 BIO_new_ssl_connect(SSL_CTX *ctx)
520 {
521 	BIO *ret = NULL, *con = NULL, *ssl = NULL;
522 
523 	if ((con = BIO_new(BIO_s_connect())) == NULL)
524 		goto err;
525 	if ((ssl = BIO_new_ssl(ctx, 1)) == NULL)
526 		goto err;
527 	if ((ret = BIO_push(ssl, con)) == NULL)
528 		goto err;
529 	return (ret);
530 
531  err:
532 	BIO_free(con);
533 	BIO_free(ssl);
534 	return (NULL);
535 }
536 LSSL_ALIAS(BIO_new_ssl_connect)
537 
538 BIO *
539 BIO_new_ssl(SSL_CTX *ctx, int client)
540 {
541 	BIO *ret;
542 	SSL *ssl;
543 
544 	if ((ret = BIO_new(BIO_f_ssl())) == NULL)
545 		goto err;
546 	if ((ssl = SSL_new(ctx)) == NULL)
547 		goto err;
548 
549 	if (client)
550 		SSL_set_connect_state(ssl);
551 	else
552 		SSL_set_accept_state(ssl);
553 
554 	BIO_set_ssl(ret, ssl, BIO_CLOSE);
555 	return (ret);
556 
557  err:
558 	BIO_free(ret);
559 	return (NULL);
560 }
561 LSSL_ALIAS(BIO_new_ssl)
562 
563 int
564 BIO_ssl_copy_session_id(BIO *t, BIO *f)
565 {
566 	t = BIO_find_type(t, BIO_TYPE_SSL);
567 	f = BIO_find_type(f, BIO_TYPE_SSL);
568 	if ((t == NULL) || (f == NULL))
569 		return (0);
570 	if ((((BIO_SSL *)t->ptr)->ssl == NULL) ||
571 	    (((BIO_SSL *)f->ptr)->ssl == NULL))
572 		return (0);
573 	if (!SSL_copy_session_id(((BIO_SSL *)t->ptr)->ssl,
574 	    ((BIO_SSL *)f->ptr)->ssl))
575 		return (0);
576 	return (1);
577 }
578 
579 void
580 BIO_ssl_shutdown(BIO *b)
581 {
582 	SSL *s;
583 
584 	while (b != NULL) {
585 		if (b->method->type == BIO_TYPE_SSL) {
586 			s = ((BIO_SSL *)b->ptr)->ssl;
587 			SSL_shutdown(s);
588 			break;
589 		}
590 		b = b->next_bio;
591 	}
592 }
593