1 /* Copyright (C) 1995-1998 Eric Young ([email protected])
2 * All rights reserved.
3 *
4 * This package is an SSL implementation written
5 * by Eric Young ([email protected]).
6 * The implementation was written so as to conform with Netscapes SSL.
7 *
8 * This library is free for commercial and non-commercial use as long as
9 * the following conditions are aheared to. The following conditions
10 * apply to all code found in this distribution, be it the RC4, RSA,
11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
12 * included with this distribution is covered by the same copyright terms
13 * except that the holder is Tim Hudson ([email protected]).
14 *
15 * Copyright remains Eric Young's, and as such any Copyright notices in
16 * the code are not to be removed.
17 * If this package is used in a product, Eric Young should be given attribution
18 * as the author of the parts of the library used.
19 * This can be in the form of a textual message at program startup or
20 * in documentation (online or textual) provided with the package.
21 *
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
24 * are met:
25 * 1. Redistributions of source code must retain the copyright
26 * notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
28 * notice, this list of conditions and the following disclaimer in the
29 * documentation and/or other materials provided with the distribution.
30 * 3. All advertising materials mentioning features or use of this software
31 * must display the following acknowledgement:
32 * "This product includes cryptographic software written by
33 * Eric Young ([email protected])"
34 * The word 'cryptographic' can be left out if the rouines from the library
35 * being used are not cryptographic related :-).
36 * 4. If you include any Windows specific code (or a derivative thereof) from
37 * the apps directory (application code) you must include an acknowledgement:
38 * "This product includes software written by Tim Hudson ([email protected])"
39 *
40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
50 * SUCH DAMAGE.
51 *
52 * The licence and distribution terms for any publically available version or
53 * derivative of this code cannot be changed. i.e. this code cannot simply be
54 * copied and put under another distribution licence
55 * [including the GNU Public Licence.]
56 */
57 /* ====================================================================
58 * Copyright (c) 1998-2002 The OpenSSL Project. All rights reserved.
59 *
60 * Redistribution and use in source and binary forms, with or without
61 * modification, are permitted provided that the following conditions
62 * are met:
63 *
64 * 1. Redistributions of source code must retain the above copyright
65 * notice, this list of conditions and the following disclaimer.
66 *
67 * 2. Redistributions in binary form must reproduce the above copyright
68 * notice, this list of conditions and the following disclaimer in
69 * the documentation and/or other materials provided with the
70 * distribution.
71 *
72 * 3. All advertising materials mentioning features or use of this
73 * software must display the following acknowledgment:
74 * "This product includes software developed by the OpenSSL Project
75 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
76 *
77 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
78 * endorse or promote products derived from this software without
79 * prior written permission. For written permission, please contact
80 * [email protected].
81 *
82 * 5. Products derived from this software may not be called "OpenSSL"
83 * nor may "OpenSSL" appear in their names without prior written
84 * permission of the OpenSSL Project.
85 *
86 * 6. Redistributions of any form whatsoever must retain the following
87 * acknowledgment:
88 * "This product includes software developed by the OpenSSL Project
89 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
90 *
91 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
92 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
93 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
94 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
95 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
96 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
97 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
98 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
99 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
100 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
101 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
102 * OF THE POSSIBILITY OF SUCH DAMAGE.
103 * ====================================================================
104 *
105 * This product includes cryptographic software written by Eric Young
106 * ([email protected]). This product includes software written by Tim
107 * Hudson ([email protected]). */
108
109 #include <openssl/ssl.h>
110
111 #include <assert.h>
112 #include <limits.h>
113 #include <string.h>
114
115 #include <algorithm>
116
117 #include <openssl/err.h>
118 #include <openssl/evp.h>
119 #include <openssl/mem.h>
120 #include <openssl/rand.h>
121
122 #include "../crypto/err/internal.h"
123 #include "../crypto/internal.h"
124 #include "internal.h"
125
126
127 BSSL_NAMESPACE_BEGIN
128
129 static int do_tls_write(SSL *ssl, size_t *out_bytes_written, uint8_t type,
130 Span<const uint8_t> in);
131
tls_write_app_data(SSL * ssl,bool * out_needs_handshake,size_t * out_bytes_written,Span<const uint8_t> in)132 int tls_write_app_data(SSL *ssl, bool *out_needs_handshake,
133 size_t *out_bytes_written, Span<const uint8_t> in) {
134 assert(ssl_can_write(ssl));
135 assert(!ssl->s3->aead_write_ctx->is_null_cipher());
136
137 *out_needs_handshake = false;
138
139 if (ssl->s3->write_shutdown != ssl_shutdown_none) {
140 OPENSSL_PUT_ERROR(SSL, SSL_R_PROTOCOL_IS_SHUTDOWN);
141 return -1;
142 }
143
144 size_t total_bytes_written = ssl->s3->unreported_bytes_written;
145 if (in.size() < total_bytes_written) {
146 // This can happen if the caller disables |SSL_MODE_ENABLE_PARTIAL_WRITE|,
147 // asks us to write some input of length N, we successfully encrypt M bytes
148 // and write it, but fail to write the rest. We will report
149 // |SSL_ERROR_WANT_WRITE|. If the caller then retries with fewer than M
150 // bytes, we cannot satisfy that request. The caller is required to always
151 // retry with at least as many bytes as the previous attempt.
152 OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_LENGTH);
153 return -1;
154 }
155
156 in = in.subspan(total_bytes_written);
157
158 const bool is_early_data_write =
159 !ssl->server && SSL_in_early_data(ssl) && ssl->s3->hs->can_early_write;
160 for (;;) {
161 size_t max_send_fragment = ssl->max_send_fragment;
162 if (is_early_data_write) {
163 SSL_HANDSHAKE *hs = ssl->s3->hs.get();
164 if (hs->early_data_written >= hs->early_session->ticket_max_early_data) {
165 ssl->s3->unreported_bytes_written = total_bytes_written;
166 hs->can_early_write = false;
167 *out_needs_handshake = true;
168 return -1;
169 }
170 max_send_fragment = std::min(
171 max_send_fragment, size_t{hs->early_session->ticket_max_early_data -
172 hs->early_data_written});
173 }
174
175 const size_t to_write = std::min(max_send_fragment, in.size());
176 size_t bytes_written;
177 int ret = do_tls_write(ssl, &bytes_written, SSL3_RT_APPLICATION_DATA,
178 in.subspan(0, to_write));
179 if (ret <= 0) {
180 ssl->s3->unreported_bytes_written = total_bytes_written;
181 return ret;
182 }
183
184 // Note |bytes_written| may be less than |to_write| if there was a pending
185 // record from a smaller write attempt.
186 assert(bytes_written <= to_write);
187 total_bytes_written += bytes_written;
188 in = in.subspan(bytes_written);
189 if (is_early_data_write) {
190 ssl->s3->hs->early_data_written += bytes_written;
191 }
192
193 if (in.empty() || (ssl->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)) {
194 ssl->s3->unreported_bytes_written = 0;
195 *out_bytes_written = total_bytes_written;
196 return 1;
197 }
198 }
199 }
200
201 // do_tls_write writes an SSL record of the given type. On success, it sets
202 // |*out_bytes_written| to number of bytes successfully written and returns one.
203 // On error, it returns a value <= 0 from the underlying |BIO|.
do_tls_write(SSL * ssl,size_t * out_bytes_written,uint8_t type,Span<const uint8_t> in)204 static int do_tls_write(SSL *ssl, size_t *out_bytes_written, uint8_t type,
205 Span<const uint8_t> in) {
206 // If there is a pending write, the retry must be consistent.
207 if (!ssl->s3->pending_write.empty() &&
208 (ssl->s3->pending_write.size() > in.size() ||
209 (!(ssl->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER) &&
210 ssl->s3->pending_write.data() != in.data()) ||
211 ssl->s3->pending_write_type != type)) {
212 OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_WRITE_RETRY);
213 return -1;
214 }
215
216 // Flush any unwritten data to the transport. There may be data to flush even
217 // if |wpend_tot| is zero.
218 int ret = ssl_write_buffer_flush(ssl);
219 if (ret <= 0) {
220 return ret;
221 }
222
223 // If there is a pending write, we just completed it. Report it to the caller.
224 if (!ssl->s3->pending_write.empty()) {
225 *out_bytes_written = ssl->s3->pending_write.size();
226 ssl->s3->pending_write = {};
227 return 1;
228 }
229
230 SSLBuffer *buf = &ssl->s3->write_buffer;
231 if (in.size() > SSL3_RT_MAX_PLAIN_LENGTH || buf->size() > 0) {
232 OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
233 return -1;
234 }
235
236 if (!tls_flush_pending_hs_data(ssl)) {
237 return -1;
238 }
239
240 // We may have unflushed handshake data that must be written before |in|. This
241 // may be a KeyUpdate acknowledgment, 0-RTT key change messages, or a
242 // NewSessionTicket.
243 Span<const uint8_t> pending_flight;
244 if (ssl->s3->pending_flight != nullptr) {
245 pending_flight = MakeConstSpan(
246 reinterpret_cast<const uint8_t *>(ssl->s3->pending_flight->data),
247 ssl->s3->pending_flight->length);
248 pending_flight = pending_flight.subspan(ssl->s3->pending_flight_offset);
249 }
250
251 size_t max_out = pending_flight.size();
252 if (!in.empty()) {
253 const size_t max_ciphertext_len = in.size() + SSL_max_seal_overhead(ssl);
254 if (max_ciphertext_len < in.size() ||
255 max_out + max_ciphertext_len < max_out) {
256 OPENSSL_PUT_ERROR(SSL, ERR_R_OVERFLOW);
257 return -1;
258 }
259 max_out += max_ciphertext_len;
260 }
261
262 if (max_out == 0) {
263 // Nothing to write.
264 *out_bytes_written = 0;
265 return 1;
266 }
267
268 if (!buf->EnsureCap(pending_flight.size() + ssl_seal_align_prefix_len(ssl),
269 max_out)) {
270 return -1;
271 }
272
273 // Copy |pending_flight| to the output.
274 if (!pending_flight.empty()) {
275 OPENSSL_memcpy(buf->remaining().data(), pending_flight.data(),
276 pending_flight.size());
277 ssl->s3->pending_flight.reset();
278 ssl->s3->pending_flight_offset = 0;
279 buf->DidWrite(pending_flight.size());
280 }
281
282 if (!in.empty()) {
283 size_t ciphertext_len;
284 if (!tls_seal_record(ssl, buf->remaining().data(), &ciphertext_len,
285 buf->remaining().size(), type, in.data(), in.size())) {
286 return -1;
287 }
288 buf->DidWrite(ciphertext_len);
289 }
290
291 // Now that we've made progress on the connection, uncork KeyUpdate
292 // acknowledgments.
293 ssl->s3->key_update_pending = false;
294
295 // Flush the write buffer.
296 ret = ssl_write_buffer_flush(ssl);
297 if (ret <= 0) {
298 // Track the unfinished write.
299 if (!in.empty()) {
300 ssl->s3->pending_write = in;
301 ssl->s3->pending_write_type = type;
302 }
303 return ret;
304 }
305
306 *out_bytes_written = in.size();
307 return 1;
308 }
309
tls_open_app_data(SSL * ssl,Span<uint8_t> * out,size_t * out_consumed,uint8_t * out_alert,Span<uint8_t> in)310 ssl_open_record_t tls_open_app_data(SSL *ssl, Span<uint8_t> *out,
311 size_t *out_consumed, uint8_t *out_alert,
312 Span<uint8_t> in) {
313 assert(ssl_can_read(ssl));
314 assert(!ssl->s3->aead_read_ctx->is_null_cipher());
315
316 uint8_t type;
317 Span<uint8_t> body;
318 auto ret = tls_open_record(ssl, &type, &body, out_consumed, out_alert, in);
319 if (ret != ssl_open_record_success) {
320 return ret;
321 }
322
323 const bool is_early_data_read = ssl->server && SSL_in_early_data(ssl);
324
325 if (type == SSL3_RT_HANDSHAKE) {
326 // Post-handshake data prior to TLS 1.3 is always renegotiation, which we
327 // never accept as a server. Otherwise |tls_get_message| will send
328 // |SSL_R_EXCESSIVE_MESSAGE_SIZE|.
329 if (ssl->server && ssl_protocol_version(ssl) < TLS1_3_VERSION) {
330 OPENSSL_PUT_ERROR(SSL, SSL_R_NO_RENEGOTIATION);
331 *out_alert = SSL_AD_NO_RENEGOTIATION;
332 return ssl_open_record_error;
333 }
334
335 if (!tls_append_handshake_data(ssl, body)) {
336 *out_alert = SSL_AD_INTERNAL_ERROR;
337 return ssl_open_record_error;
338 }
339 return ssl_open_record_discard;
340 }
341
342 if (type != SSL3_RT_APPLICATION_DATA) {
343 OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_RECORD);
344 *out_alert = SSL_AD_UNEXPECTED_MESSAGE;
345 return ssl_open_record_error;
346 }
347
348 if (is_early_data_read) {
349 if (body.size() > kMaxEarlyDataAccepted - ssl->s3->hs->early_data_read) {
350 OPENSSL_PUT_ERROR(SSL, SSL_R_TOO_MUCH_READ_EARLY_DATA);
351 *out_alert = SSL3_AD_UNEXPECTED_MESSAGE;
352 return ssl_open_record_error;
353 }
354
355 ssl->s3->hs->early_data_read += body.size();
356 }
357
358 if (body.empty()) {
359 return ssl_open_record_discard;
360 }
361
362 *out = body;
363 return ssl_open_record_success;
364 }
365
tls_open_change_cipher_spec(SSL * ssl,size_t * out_consumed,uint8_t * out_alert,Span<uint8_t> in)366 ssl_open_record_t tls_open_change_cipher_spec(SSL *ssl, size_t *out_consumed,
367 uint8_t *out_alert,
368 Span<uint8_t> in) {
369 uint8_t type;
370 Span<uint8_t> body;
371 auto ret = tls_open_record(ssl, &type, &body, out_consumed, out_alert, in);
372 if (ret != ssl_open_record_success) {
373 return ret;
374 }
375
376 if (type != SSL3_RT_CHANGE_CIPHER_SPEC) {
377 OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_RECORD);
378 *out_alert = SSL_AD_UNEXPECTED_MESSAGE;
379 return ssl_open_record_error;
380 }
381
382 if (body.size() != 1 || body[0] != SSL3_MT_CCS) {
383 OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_CHANGE_CIPHER_SPEC);
384 *out_alert = SSL_AD_ILLEGAL_PARAMETER;
385 return ssl_open_record_error;
386 }
387
388 ssl_do_msg_callback(ssl, 0 /* read */, SSL3_RT_CHANGE_CIPHER_SPEC, body);
389 return ssl_open_record_success;
390 }
391
ssl_send_alert(SSL * ssl,int level,int desc)392 void ssl_send_alert(SSL *ssl, int level, int desc) {
393 // This function is called in response to a fatal error from the peer. Ignore
394 // any failures writing the alert and report only the original error. In
395 // particular, if the transport uses |SSL_write|, our existing error will be
396 // clobbered so we must save and restore the error queue. See
397 // https://crbug.com/959305.
398 //
399 // TODO(davidben): Return the alert out of the handshake, rather than calling
400 // this function internally everywhere.
401 //
402 // TODO(davidben): This does not allow retrying if the alert hit EAGAIN. See
403 // https://crbug.com/boringssl/130.
404 UniquePtr<ERR_SAVE_STATE> err_state(ERR_save_state());
405 ssl_send_alert_impl(ssl, level, desc);
406 ERR_restore_state(err_state.get());
407 }
408
ssl_send_alert_impl(SSL * ssl,int level,int desc)409 int ssl_send_alert_impl(SSL *ssl, int level, int desc) {
410 // It is illegal to send an alert when we've already sent a closing one.
411 if (ssl->s3->write_shutdown != ssl_shutdown_none) {
412 OPENSSL_PUT_ERROR(SSL, SSL_R_PROTOCOL_IS_SHUTDOWN);
413 return -1;
414 }
415
416 if (level == SSL3_AL_WARNING && desc == SSL_AD_CLOSE_NOTIFY) {
417 ssl->s3->write_shutdown = ssl_shutdown_close_notify;
418 } else {
419 assert(level == SSL3_AL_FATAL);
420 assert(desc != SSL_AD_CLOSE_NOTIFY);
421 ssl->s3->write_shutdown = ssl_shutdown_error;
422 }
423
424 ssl->s3->alert_dispatch = true;
425 ssl->s3->send_alert[0] = level;
426 ssl->s3->send_alert[1] = desc;
427 if (ssl->s3->write_buffer.empty()) {
428 // Nothing is being written out, so the alert may be dispatched
429 // immediately.
430 return ssl->method->dispatch_alert(ssl);
431 }
432
433 // The alert will be dispatched later.
434 return -1;
435 }
436
tls_dispatch_alert(SSL * ssl)437 int tls_dispatch_alert(SSL *ssl) {
438 if (ssl->quic_method) {
439 if (!ssl->quic_method->send_alert(ssl, ssl->s3->write_level,
440 ssl->s3->send_alert[1])) {
441 OPENSSL_PUT_ERROR(SSL, SSL_R_QUIC_INTERNAL_ERROR);
442 return 0;
443 }
444 } else {
445 size_t bytes_written;
446 int ret =
447 do_tls_write(ssl, &bytes_written, SSL3_RT_ALERT, ssl->s3->send_alert);
448 if (ret <= 0) {
449 return ret;
450 }
451 assert(bytes_written == 2);
452 }
453
454 ssl->s3->alert_dispatch = false;
455
456 // If the alert is fatal, flush the BIO now.
457 if (ssl->s3->send_alert[0] == SSL3_AL_FATAL) {
458 BIO_flush(ssl->wbio.get());
459 }
460
461 ssl_do_msg_callback(ssl, 1 /* write */, SSL3_RT_ALERT, ssl->s3->send_alert);
462
463 int alert = (ssl->s3->send_alert[0] << 8) | ssl->s3->send_alert[1];
464 ssl_do_info_callback(ssl, SSL_CB_WRITE_ALERT, alert);
465
466 return 1;
467 }
468
469 BSSL_NAMESPACE_END
470