1 /***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 2010 - 2011, Hoi-Ho Chan, <hoiho.chan@gmail.com>
9 * Copyright (C) 2012 - 2020, Daniel Stenberg, <daniel@haxx.se>, et al.
10 *
11 * This software is licensed as described in the file COPYING, which
12 * you should have received as part of this distribution. The terms
13 * are also available at https://curl.haxx.se/docs/copyright.html.
14 *
15 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
16 * copies of the Software, and permit persons to whom the Software is
17 * furnished to do so, under the terms of the COPYING file.
18 *
19 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
20 * KIND, either express or implied.
21 *
22 ***************************************************************************/
23
24 /*
25 * Source file for all mbedTLS-specific code for the TLS/SSL layer. No code
26 * but vtls.c should ever call or use these functions.
27 *
28 */
29
30 #include "curl_setup.h"
31
32 #ifdef USE_MBEDTLS
33
34 /* Define this to enable lots of debugging for mbedTLS */
35 /* #define MBEDTLS_DEBUG */
36
37 #include <mbedtls/version.h>
38 #if MBEDTLS_VERSION_NUMBER >= 0x02040000
39 #include <mbedtls/net_sockets.h>
40 #else
41 #include <mbedtls/net.h>
42 #endif
43 #include <mbedtls/ssl.h>
44 #include <mbedtls/certs.h>
45 #include <mbedtls/x509.h>
46
47 #include <mbedtls/error.h>
48 #include <mbedtls/entropy.h>
49 #include <mbedtls/ctr_drbg.h>
50 #include <mbedtls/sha256.h>
51
52 #if MBEDTLS_VERSION_MAJOR >= 2
53 # ifdef MBEDTLS_DEBUG
54 # include <mbedtls/debug.h>
55 # endif
56 #endif
57
58 #include "urldata.h"
59 #include "sendf.h"
60 #include "inet_pton.h"
61 #include "mbedtls.h"
62 #include "vtls.h"
63 #include "parsedate.h"
64 #include "connect.h" /* for the connect timeout */
65 #include "select.h"
66 #include "multiif.h"
67 #include "mbedtls_threadlock.h"
68
69 /* The last 3 #include files should be in this order */
70 #include "curl_printf.h"
71 #include "curl_memory.h"
72 #include "memdebug.h"
73
74 struct ssl_backend_data {
75 mbedtls_ctr_drbg_context ctr_drbg;
76 mbedtls_entropy_context entropy;
77 mbedtls_ssl_context ssl;
78 int server_fd;
79 mbedtls_x509_crt cacert;
80 mbedtls_x509_crt clicert;
81 mbedtls_x509_crl crl;
82 mbedtls_pk_context pk;
83 mbedtls_ssl_config config;
84 const char *protocols[3];
85 };
86
87 /* apply threading? */
88 #if defined(USE_THREADS_POSIX) || defined(USE_THREADS_WIN32)
89 #define THREADING_SUPPORT
90 #endif
91
92 #if defined(THREADING_SUPPORT)
93 static mbedtls_entropy_context ts_entropy;
94
95 static int entropy_init_initialized = 0;
96
97 /* start of entropy_init_mutex() */
entropy_init_mutex(mbedtls_entropy_context * ctx)98 static void entropy_init_mutex(mbedtls_entropy_context *ctx)
99 {
100 /* lock 0 = entropy_init_mutex() */
101 Curl_mbedtlsthreadlock_lock_function(0);
102 if(entropy_init_initialized == 0) {
103 mbedtls_entropy_init(ctx);
104 entropy_init_initialized = 1;
105 }
106 Curl_mbedtlsthreadlock_unlock_function(0);
107 }
108 /* end of entropy_init_mutex() */
109
110 /* start of entropy_func_mutex() */
entropy_func_mutex(void * data,unsigned char * output,size_t len)111 static int entropy_func_mutex(void *data, unsigned char *output, size_t len)
112 {
113 int ret;
114 /* lock 1 = entropy_func_mutex() */
115 Curl_mbedtlsthreadlock_lock_function(1);
116 ret = mbedtls_entropy_func(data, output, len);
117 Curl_mbedtlsthreadlock_unlock_function(1);
118
119 return ret;
120 }
121 /* end of entropy_func_mutex() */
122
123 #endif /* THREADING_SUPPORT */
124
125 #ifdef MBEDTLS_DEBUG
mbed_debug(void * context,int level,const char * f_name,int line_nb,const char * line)126 static void mbed_debug(void *context, int level, const char *f_name,
127 int line_nb, const char *line)
128 {
129 struct Curl_easy *data = NULL;
130
131 if(!context)
132 return;
133
134 data = (struct Curl_easy *)context;
135
136 infof(data, "%s", line);
137 (void) level;
138 }
139 #else
140 #endif
141
142 /* ALPN for http2? */
143 #ifdef USE_NGHTTP2
144 # undef HAS_ALPN
145 # ifdef MBEDTLS_SSL_ALPN
146 # define HAS_ALPN
147 # endif
148 #endif
149
150
151 /*
152 * profile
153 */
154 static const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_fr =
155 {
156 /* Hashes from SHA-1 and above */
157 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA1) |
158 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_RIPEMD160) |
159 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA224) |
160 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA256) |
161 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA384) |
162 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA512),
163 0xFFFFFFF, /* Any PK alg */
164 0xFFFFFFF, /* Any curve */
165 1024, /* RSA min key len */
166 };
167
168 /* See https://tls.mbed.org/discussions/generic/
169 howto-determine-exact-buffer-len-for-mbedtls_pk_write_pubkey_der
170 */
171 #define RSA_PUB_DER_MAX_BYTES (38 + 2 * MBEDTLS_MPI_MAX_SIZE)
172 #define ECP_PUB_DER_MAX_BYTES (30 + 2 * MBEDTLS_ECP_MAX_BYTES)
173
174 #define PUB_DER_MAX_BYTES (RSA_PUB_DER_MAX_BYTES > ECP_PUB_DER_MAX_BYTES ? \
175 RSA_PUB_DER_MAX_BYTES : ECP_PUB_DER_MAX_BYTES)
176
177 static Curl_recv mbed_recv;
178 static Curl_send mbed_send;
179
mbedtls_version_from_curl(int * mbedver,long version)180 static CURLcode mbedtls_version_from_curl(int *mbedver, long version)
181 {
182 switch(version) {
183 case CURL_SSLVERSION_TLSv1_0:
184 *mbedver = MBEDTLS_SSL_MINOR_VERSION_1;
185 return CURLE_OK;
186 case CURL_SSLVERSION_TLSv1_1:
187 *mbedver = MBEDTLS_SSL_MINOR_VERSION_2;
188 return CURLE_OK;
189 case CURL_SSLVERSION_TLSv1_2:
190 *mbedver = MBEDTLS_SSL_MINOR_VERSION_3;
191 return CURLE_OK;
192 case CURL_SSLVERSION_TLSv1_3:
193 break;
194 }
195 return CURLE_SSL_CONNECT_ERROR;
196 }
197
198 static CURLcode
set_ssl_version_min_max(struct connectdata * conn,int sockindex)199 set_ssl_version_min_max(struct connectdata *conn, int sockindex)
200 {
201 struct Curl_easy *data = conn->data;
202 struct ssl_connect_data *connssl = &conn->ssl[sockindex];
203 struct ssl_backend_data *backend = connssl->backend;
204 int mbedtls_ver_min = MBEDTLS_SSL_MINOR_VERSION_1;
205 int mbedtls_ver_max = MBEDTLS_SSL_MINOR_VERSION_1;
206 long ssl_version = SSL_CONN_CONFIG(version);
207 long ssl_version_max = SSL_CONN_CONFIG(version_max);
208 CURLcode result = CURLE_OK;
209
210 switch(ssl_version) {
211 case CURL_SSLVERSION_DEFAULT:
212 case CURL_SSLVERSION_TLSv1:
213 ssl_version = CURL_SSLVERSION_TLSv1_0;
214 break;
215 }
216
217 switch(ssl_version_max) {
218 case CURL_SSLVERSION_MAX_NONE:
219 case CURL_SSLVERSION_MAX_DEFAULT:
220 ssl_version_max = CURL_SSLVERSION_MAX_TLSv1_2;
221 break;
222 }
223
224 result = mbedtls_version_from_curl(&mbedtls_ver_min, ssl_version);
225 if(result) {
226 failf(data, "unsupported min version passed via CURLOPT_SSLVERSION");
227 return result;
228 }
229 result = mbedtls_version_from_curl(&mbedtls_ver_max, ssl_version_max >> 16);
230 if(result) {
231 failf(data, "unsupported max version passed via CURLOPT_SSLVERSION");
232 return result;
233 }
234
235 mbedtls_ssl_conf_min_version(&backend->config, MBEDTLS_SSL_MAJOR_VERSION_3,
236 mbedtls_ver_min);
237 mbedtls_ssl_conf_max_version(&backend->config, MBEDTLS_SSL_MAJOR_VERSION_3,
238 mbedtls_ver_max);
239
240 return result;
241 }
242
243 static CURLcode
mbed_connect_step1(struct connectdata * conn,int sockindex)244 mbed_connect_step1(struct connectdata *conn,
245 int sockindex)
246 {
247 struct Curl_easy *data = conn->data;
248 struct ssl_connect_data *connssl = &conn->ssl[sockindex];
249 struct ssl_backend_data *backend = connssl->backend;
250 const char * const ssl_cafile = SSL_CONN_CONFIG(CAfile);
251 const bool verifypeer = SSL_CONN_CONFIG(verifypeer);
252 const char * const ssl_capath = SSL_CONN_CONFIG(CApath);
253 char * const ssl_cert = SSL_SET_OPTION(primary.clientcert);
254 const char * const ssl_crlfile = SSL_SET_OPTION(CRLfile);
255 #ifndef CURL_DISABLE_PROXY
256 const char * const hostname = SSL_IS_PROXY() ? conn->http_proxy.host.name :
257 conn->host.name;
258 const long int port = SSL_IS_PROXY() ? conn->port : conn->remote_port;
259 #else
260 const char * const hostname = conn->host.name;
261 const long int port = conn->remote_port;
262 #endif
263 int ret = -1;
264 char errorbuf[128];
265 errorbuf[0] = 0;
266
267 /* mbedTLS only supports SSLv3 and TLSv1 */
268 if(SSL_CONN_CONFIG(version) == CURL_SSLVERSION_SSLv2) {
269 failf(data, "mbedTLS does not support SSLv2");
270 return CURLE_SSL_CONNECT_ERROR;
271 }
272
273 #ifdef THREADING_SUPPORT
274 entropy_init_mutex(&ts_entropy);
275 mbedtls_ctr_drbg_init(&backend->ctr_drbg);
276
277 ret = mbedtls_ctr_drbg_seed(&backend->ctr_drbg, entropy_func_mutex,
278 &ts_entropy, NULL, 0);
279 if(ret) {
280 #ifdef MBEDTLS_ERROR_C
281 mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
282 #endif /* MBEDTLS_ERROR_C */
283 failf(data, "Failed - mbedTLS: ctr_drbg_init returned (-0x%04X) %s\n",
284 -ret, errorbuf);
285 }
286 #else
287 mbedtls_entropy_init(&backend->entropy);
288 mbedtls_ctr_drbg_init(&backend->ctr_drbg);
289
290 ret = mbedtls_ctr_drbg_seed(&backend->ctr_drbg, mbedtls_entropy_func,
291 &backend->entropy, NULL, 0);
292 if(ret) {
293 #ifdef MBEDTLS_ERROR_C
294 mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
295 #endif /* MBEDTLS_ERROR_C */
296 failf(data, "Failed - mbedTLS: ctr_drbg_init returned (-0x%04X) %s\n",
297 -ret, errorbuf);
298 }
299 #endif /* THREADING_SUPPORT */
300
301 /* Load the trusted CA */
302 mbedtls_x509_crt_init(&backend->cacert);
303
304 if(ssl_cafile) {
305 ret = mbedtls_x509_crt_parse_file(&backend->cacert, ssl_cafile);
306
307 if(ret<0) {
308 #ifdef MBEDTLS_ERROR_C
309 mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
310 #endif /* MBEDTLS_ERROR_C */
311 failf(data, "Error reading ca cert file %s - mbedTLS: (-0x%04X) %s",
312 ssl_cafile, -ret, errorbuf);
313
314 if(verifypeer)
315 return CURLE_SSL_CACERT_BADFILE;
316 }
317 }
318
319 if(ssl_capath) {
320 ret = mbedtls_x509_crt_parse_path(&backend->cacert, ssl_capath);
321
322 if(ret<0) {
323 #ifdef MBEDTLS_ERROR_C
324 mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
325 #endif /* MBEDTLS_ERROR_C */
326 failf(data, "Error reading ca cert path %s - mbedTLS: (-0x%04X) %s",
327 ssl_capath, -ret, errorbuf);
328
329 if(verifypeer)
330 return CURLE_SSL_CACERT_BADFILE;
331 }
332 }
333
334 /* Load the client certificate */
335 mbedtls_x509_crt_init(&backend->clicert);
336
337 if(ssl_cert) {
338 ret = mbedtls_x509_crt_parse_file(&backend->clicert, ssl_cert);
339
340 if(ret) {
341 #ifdef MBEDTLS_ERROR_C
342 mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
343 #endif /* MBEDTLS_ERROR_C */
344 failf(data, "Error reading client cert file %s - mbedTLS: (-0x%04X) %s",
345 ssl_cert, -ret, errorbuf);
346
347 return CURLE_SSL_CERTPROBLEM;
348 }
349 }
350
351 /* Load the client private key */
352 mbedtls_pk_init(&backend->pk);
353
354 if(SSL_SET_OPTION(key)) {
355 ret = mbedtls_pk_parse_keyfile(&backend->pk, SSL_SET_OPTION(key),
356 SSL_SET_OPTION(key_passwd));
357 if(ret == 0 && !(mbedtls_pk_can_do(&backend->pk, MBEDTLS_PK_RSA) ||
358 mbedtls_pk_can_do(&backend->pk, MBEDTLS_PK_ECKEY)))
359 ret = MBEDTLS_ERR_PK_TYPE_MISMATCH;
360
361 if(ret) {
362 #ifdef MBEDTLS_ERROR_C
363 mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
364 #endif /* MBEDTLS_ERROR_C */
365 failf(data, "Error reading private key %s - mbedTLS: (-0x%04X) %s",
366 SSL_SET_OPTION(key), -ret, errorbuf);
367
368 return CURLE_SSL_CERTPROBLEM;
369 }
370 }
371
372 /* Load the CRL */
373 mbedtls_x509_crl_init(&backend->crl);
374
375 if(ssl_crlfile) {
376 ret = mbedtls_x509_crl_parse_file(&backend->crl, ssl_crlfile);
377
378 if(ret) {
379 #ifdef MBEDTLS_ERROR_C
380 mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
381 #endif /* MBEDTLS_ERROR_C */
382 failf(data, "Error reading CRL file %s - mbedTLS: (-0x%04X) %s",
383 ssl_crlfile, -ret, errorbuf);
384
385 return CURLE_SSL_CRL_BADFILE;
386 }
387 }
388
389 infof(data, "mbedTLS: Connecting to %s:%ld\n", hostname, port);
390
391 mbedtls_ssl_config_init(&backend->config);
392
393 mbedtls_ssl_init(&backend->ssl);
394 if(mbedtls_ssl_setup(&backend->ssl, &backend->config)) {
395 failf(data, "mbedTLS: ssl_init failed");
396 return CURLE_SSL_CONNECT_ERROR;
397 }
398 ret = mbedtls_ssl_config_defaults(&backend->config,
399 MBEDTLS_SSL_IS_CLIENT,
400 MBEDTLS_SSL_TRANSPORT_STREAM,
401 MBEDTLS_SSL_PRESET_DEFAULT);
402 if(ret) {
403 failf(data, "mbedTLS: ssl_config failed");
404 return CURLE_SSL_CONNECT_ERROR;
405 }
406
407 /* new profile with RSA min key len = 1024 ... */
408 mbedtls_ssl_conf_cert_profile(&backend->config,
409 &mbedtls_x509_crt_profile_fr);
410
411 switch(SSL_CONN_CONFIG(version)) {
412 case CURL_SSLVERSION_DEFAULT:
413 case CURL_SSLVERSION_TLSv1:
414 mbedtls_ssl_conf_min_version(&backend->config, MBEDTLS_SSL_MAJOR_VERSION_3,
415 MBEDTLS_SSL_MINOR_VERSION_1);
416 infof(data, "mbedTLS: Set min SSL version to TLS 1.0\n");
417 break;
418 case CURL_SSLVERSION_SSLv3:
419 mbedtls_ssl_conf_min_version(&backend->config, MBEDTLS_SSL_MAJOR_VERSION_3,
420 MBEDTLS_SSL_MINOR_VERSION_0);
421 mbedtls_ssl_conf_max_version(&backend->config, MBEDTLS_SSL_MAJOR_VERSION_3,
422 MBEDTLS_SSL_MINOR_VERSION_0);
423 infof(data, "mbedTLS: Set SSL version to SSLv3\n");
424 break;
425 case CURL_SSLVERSION_TLSv1_0:
426 case CURL_SSLVERSION_TLSv1_1:
427 case CURL_SSLVERSION_TLSv1_2:
428 case CURL_SSLVERSION_TLSv1_3:
429 {
430 CURLcode result = set_ssl_version_min_max(conn, sockindex);
431 if(result != CURLE_OK)
432 return result;
433 break;
434 }
435 default:
436 failf(data, "Unrecognized parameter passed via CURLOPT_SSLVERSION");
437 return CURLE_SSL_CONNECT_ERROR;
438 }
439
440 mbedtls_ssl_conf_authmode(&backend->config, MBEDTLS_SSL_VERIFY_OPTIONAL);
441
442 mbedtls_ssl_conf_rng(&backend->config, mbedtls_ctr_drbg_random,
443 &backend->ctr_drbg);
444 mbedtls_ssl_set_bio(&backend->ssl, &conn->sock[sockindex],
445 mbedtls_net_send,
446 mbedtls_net_recv,
447 NULL /* rev_timeout() */);
448
449 mbedtls_ssl_conf_ciphersuites(&backend->config,
450 mbedtls_ssl_list_ciphersuites());
451
452 #if defined(MBEDTLS_SSL_RENEGOTIATION)
453 mbedtls_ssl_conf_renegotiation(&backend->config,
454 MBEDTLS_SSL_RENEGOTIATION_ENABLED);
455 #endif
456
457 #if defined(MBEDTLS_SSL_SESSION_TICKETS)
458 mbedtls_ssl_conf_session_tickets(&backend->config,
459 MBEDTLS_SSL_SESSION_TICKETS_DISABLED);
460 #endif
461
462 /* Check if there's a cached ID we can/should use here! */
463 if(SSL_SET_OPTION(primary.sessionid)) {
464 void *old_session = NULL;
465
466 Curl_ssl_sessionid_lock(conn);
467 if(!Curl_ssl_getsessionid(conn, &old_session, NULL, sockindex)) {
468 ret = mbedtls_ssl_set_session(&backend->ssl, old_session);
469 if(ret) {
470 Curl_ssl_sessionid_unlock(conn);
471 failf(data, "mbedtls_ssl_set_session returned -0x%x", -ret);
472 return CURLE_SSL_CONNECT_ERROR;
473 }
474 infof(data, "mbedTLS re-using session\n");
475 }
476 Curl_ssl_sessionid_unlock(conn);
477 }
478
479 mbedtls_ssl_conf_ca_chain(&backend->config,
480 &backend->cacert,
481 &backend->crl);
482
483 if(SSL_SET_OPTION(key)) {
484 mbedtls_ssl_conf_own_cert(&backend->config,
485 &backend->clicert, &backend->pk);
486 }
487 if(mbedtls_ssl_set_hostname(&backend->ssl, hostname)) {
488 /* mbedtls_ssl_set_hostname() sets the name to use in CN/SAN checks *and*
489 the name to set in the SNI extension. So even if curl connects to a
490 host specified as an IP address, this function must be used. */
491 failf(data, "couldn't set hostname in mbedTLS");
492 return CURLE_SSL_CONNECT_ERROR;
493 }
494
495 #ifdef HAS_ALPN
496 if(conn->bits.tls_enable_alpn) {
497 const char **p = &backend->protocols[0];
498 #ifdef USE_NGHTTP2
499 if(data->set.httpversion >= CURL_HTTP_VERSION_2)
500 *p++ = NGHTTP2_PROTO_VERSION_ID;
501 #endif
502 *p++ = ALPN_HTTP_1_1;
503 *p = NULL;
504 /* this function doesn't clone the protocols array, which is why we need
505 to keep it around */
506 if(mbedtls_ssl_conf_alpn_protocols(&backend->config,
507 &backend->protocols[0])) {
508 failf(data, "Failed setting ALPN protocols");
509 return CURLE_SSL_CONNECT_ERROR;
510 }
511 for(p = &backend->protocols[0]; *p; ++p)
512 infof(data, "ALPN, offering %s\n", *p);
513 }
514 #endif
515
516 #ifdef MBEDTLS_DEBUG
517 /* In order to make that work in mbedtls MBEDTLS_DEBUG_C must be defined. */
518 mbedtls_ssl_conf_dbg(&backend->config, mbed_debug, data);
519 /* - 0 No debug
520 * - 1 Error
521 * - 2 State change
522 * - 3 Informational
523 * - 4 Verbose
524 */
525 mbedtls_debug_set_threshold(4);
526 #endif
527
528 /* give application a chance to interfere with mbedTLS set up. */
529 if(data->set.ssl.fsslctx) {
530 ret = (*data->set.ssl.fsslctx)(data, &backend->config,
531 data->set.ssl.fsslctxp);
532 if(ret) {
533 failf(data, "error signaled by ssl ctx callback");
534 return ret;
535 }
536 }
537
538 connssl->connecting_state = ssl_connect_2;
539
540 return CURLE_OK;
541 }
542
543 static CURLcode
mbed_connect_step2(struct connectdata * conn,int sockindex)544 mbed_connect_step2(struct connectdata *conn,
545 int sockindex)
546 {
547 int ret;
548 struct Curl_easy *data = conn->data;
549 struct ssl_connect_data *connssl = &conn->ssl[sockindex];
550 struct ssl_backend_data *backend = connssl->backend;
551 const mbedtls_x509_crt *peercert;
552 #ifndef CURL_DISABLE_PROXY
553 const char * const pinnedpubkey = SSL_IS_PROXY() ?
554 data->set.str[STRING_SSL_PINNEDPUBLICKEY_PROXY] :
555 data->set.str[STRING_SSL_PINNEDPUBLICKEY_ORIG];
556 #else
557 const char * const pinnedpubkey =
558 data->set.str[STRING_SSL_PINNEDPUBLICKEY_ORIG];
559 #endif
560
561 conn->recv[sockindex] = mbed_recv;
562 conn->send[sockindex] = mbed_send;
563
564 ret = mbedtls_ssl_handshake(&backend->ssl);
565
566 if(ret == MBEDTLS_ERR_SSL_WANT_READ) {
567 connssl->connecting_state = ssl_connect_2_reading;
568 return CURLE_OK;
569 }
570 else if(ret == MBEDTLS_ERR_SSL_WANT_WRITE) {
571 connssl->connecting_state = ssl_connect_2_writing;
572 return CURLE_OK;
573 }
574 else if(ret) {
575 char errorbuf[128];
576 errorbuf[0] = 0;
577 #ifdef MBEDTLS_ERROR_C
578 mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
579 #endif /* MBEDTLS_ERROR_C */
580 failf(data, "ssl_handshake returned - mbedTLS: (-0x%04X) %s",
581 -ret, errorbuf);
582 return CURLE_SSL_CONNECT_ERROR;
583 }
584
585 infof(data, "mbedTLS: Handshake complete, cipher is %s\n",
586 mbedtls_ssl_get_ciphersuite(&backend->ssl)
587 );
588
589 ret = mbedtls_ssl_get_verify_result(&backend->ssl);
590
591 if(!SSL_CONN_CONFIG(verifyhost))
592 /* Ignore hostname errors if verifyhost is disabled */
593 ret &= ~MBEDTLS_X509_BADCERT_CN_MISMATCH;
594
595 if(ret && SSL_CONN_CONFIG(verifypeer)) {
596 if(ret & MBEDTLS_X509_BADCERT_EXPIRED)
597 failf(data, "Cert verify failed: BADCERT_EXPIRED");
598
599 else if(ret & MBEDTLS_X509_BADCERT_REVOKED)
600 failf(data, "Cert verify failed: BADCERT_REVOKED");
601
602 else if(ret & MBEDTLS_X509_BADCERT_CN_MISMATCH)
603 failf(data, "Cert verify failed: BADCERT_CN_MISMATCH");
604
605 else if(ret & MBEDTLS_X509_BADCERT_NOT_TRUSTED)
606 failf(data, "Cert verify failed: BADCERT_NOT_TRUSTED");
607
608 else if(ret & MBEDTLS_X509_BADCERT_FUTURE)
609 failf(data, "Cert verify failed: BADCERT_FUTURE");
610
611 return CURLE_PEER_FAILED_VERIFICATION;
612 }
613
614 peercert = mbedtls_ssl_get_peer_cert(&backend->ssl);
615
616 if(peercert && data->set.verbose) {
617 const size_t bufsize = 16384;
618 char *buffer = malloc(bufsize);
619
620 if(!buffer)
621 return CURLE_OUT_OF_MEMORY;
622
623 if(mbedtls_x509_crt_info(buffer, bufsize, "* ", peercert) > 0)
624 infof(data, "Dumping cert info:\n%s\n", buffer);
625 else
626 infof(data, "Unable to dump certificate information.\n");
627
628 free(buffer);
629 }
630
631 if(pinnedpubkey) {
632 int size;
633 CURLcode result;
634 mbedtls_x509_crt *p;
635 unsigned char pubkey[PUB_DER_MAX_BYTES];
636
637 if(!peercert || !peercert->raw.p || !peercert->raw.len) {
638 failf(data, "Failed due to missing peer certificate");
639 return CURLE_SSL_PINNEDPUBKEYNOTMATCH;
640 }
641
642 p = calloc(1, sizeof(*p));
643
644 if(!p)
645 return CURLE_OUT_OF_MEMORY;
646
647 mbedtls_x509_crt_init(p);
648
649 /* Make a copy of our const peercert because mbedtls_pk_write_pubkey_der
650 needs a non-const key, for now.
651 https://github.com/ARMmbed/mbedtls/issues/396 */
652 if(mbedtls_x509_crt_parse_der(p, peercert->raw.p, peercert->raw.len)) {
653 failf(data, "Failed copying peer certificate");
654 mbedtls_x509_crt_free(p);
655 free(p);
656 return CURLE_SSL_PINNEDPUBKEYNOTMATCH;
657 }
658
659 size = mbedtls_pk_write_pubkey_der(&p->pk, pubkey, PUB_DER_MAX_BYTES);
660
661 if(size <= 0) {
662 failf(data, "Failed copying public key from peer certificate");
663 mbedtls_x509_crt_free(p);
664 free(p);
665 return CURLE_SSL_PINNEDPUBKEYNOTMATCH;
666 }
667
668 /* mbedtls_pk_write_pubkey_der writes data at the end of the buffer. */
669 result = Curl_pin_peer_pubkey(data,
670 pinnedpubkey,
671 &pubkey[PUB_DER_MAX_BYTES - size], size);
672 if(result) {
673 mbedtls_x509_crt_free(p);
674 free(p);
675 return result;
676 }
677
678 mbedtls_x509_crt_free(p);
679 free(p);
680 }
681
682 #ifdef HAS_ALPN
683 if(conn->bits.tls_enable_alpn) {
684 const char *next_protocol = mbedtls_ssl_get_alpn_protocol(&backend->ssl);
685
686 if(next_protocol) {
687 infof(data, "ALPN, server accepted to use %s\n", next_protocol);
688 #ifdef USE_NGHTTP2
689 if(!strncmp(next_protocol, NGHTTP2_PROTO_VERSION_ID,
690 NGHTTP2_PROTO_VERSION_ID_LEN) &&
691 !next_protocol[NGHTTP2_PROTO_VERSION_ID_LEN]) {
692 conn->negnpn = CURL_HTTP_VERSION_2;
693 }
694 else
695 #endif
696 if(!strncmp(next_protocol, ALPN_HTTP_1_1, ALPN_HTTP_1_1_LENGTH) &&
697 !next_protocol[ALPN_HTTP_1_1_LENGTH]) {
698 conn->negnpn = CURL_HTTP_VERSION_1_1;
699 }
700 }
701 else {
702 infof(data, "ALPN, server did not agree to a protocol\n");
703 }
704 Curl_multiuse_state(conn, conn->negnpn == CURL_HTTP_VERSION_2 ?
705 BUNDLE_MULTIPLEX : BUNDLE_NO_MULTIUSE);
706 }
707 #endif
708
709 connssl->connecting_state = ssl_connect_3;
710 infof(data, "SSL connected\n");
711
712 return CURLE_OK;
713 }
714
715 static CURLcode
mbed_connect_step3(struct connectdata * conn,int sockindex)716 mbed_connect_step3(struct connectdata *conn,
717 int sockindex)
718 {
719 CURLcode retcode = CURLE_OK;
720 struct ssl_connect_data *connssl = &conn->ssl[sockindex];
721 struct ssl_backend_data *backend = connssl->backend;
722 struct Curl_easy *data = conn->data;
723
724 DEBUGASSERT(ssl_connect_3 == connssl->connecting_state);
725
726 if(SSL_SET_OPTION(primary.sessionid)) {
727 int ret;
728 mbedtls_ssl_session *our_ssl_sessionid;
729 void *old_ssl_sessionid = NULL;
730
731 our_ssl_sessionid = malloc(sizeof(mbedtls_ssl_session));
732 if(!our_ssl_sessionid)
733 return CURLE_OUT_OF_MEMORY;
734
735 mbedtls_ssl_session_init(our_ssl_sessionid);
736
737 ret = mbedtls_ssl_get_session(&backend->ssl, our_ssl_sessionid);
738 if(ret) {
739 if(ret != MBEDTLS_ERR_SSL_ALLOC_FAILED)
740 mbedtls_ssl_session_free(our_ssl_sessionid);
741 free(our_ssl_sessionid);
742 failf(data, "mbedtls_ssl_get_session returned -0x%x", -ret);
743 return CURLE_SSL_CONNECT_ERROR;
744 }
745
746 /* If there's already a matching session in the cache, delete it */
747 Curl_ssl_sessionid_lock(conn);
748 if(!Curl_ssl_getsessionid(conn, &old_ssl_sessionid, NULL, sockindex))
749 Curl_ssl_delsessionid(conn, old_ssl_sessionid);
750
751 retcode = Curl_ssl_addsessionid(conn, our_ssl_sessionid, 0, sockindex);
752 Curl_ssl_sessionid_unlock(conn);
753 if(retcode) {
754 mbedtls_ssl_session_free(our_ssl_sessionid);
755 free(our_ssl_sessionid);
756 failf(data, "failed to store ssl session");
757 return retcode;
758 }
759 }
760
761 connssl->connecting_state = ssl_connect_done;
762
763 return CURLE_OK;
764 }
765
mbed_send(struct connectdata * conn,int sockindex,const void * mem,size_t len,CURLcode * curlcode)766 static ssize_t mbed_send(struct connectdata *conn, int sockindex,
767 const void *mem, size_t len,
768 CURLcode *curlcode)
769 {
770 struct ssl_connect_data *connssl = &conn->ssl[sockindex];
771 struct ssl_backend_data *backend = connssl->backend;
772 int ret = -1;
773
774 ret = mbedtls_ssl_write(&backend->ssl,
775 (unsigned char *)mem, len);
776
777 if(ret < 0) {
778 *curlcode = (ret == MBEDTLS_ERR_SSL_WANT_WRITE) ?
779 CURLE_AGAIN : CURLE_SEND_ERROR;
780 ret = -1;
781 }
782
783 return ret;
784 }
785
Curl_mbedtls_close_all(struct Curl_easy * data)786 static void Curl_mbedtls_close_all(struct Curl_easy *data)
787 {
788 (void)data;
789 }
790
Curl_mbedtls_close(struct connectdata * conn,int sockindex)791 static void Curl_mbedtls_close(struct connectdata *conn, int sockindex)
792 {
793 struct ssl_connect_data *connssl = &conn->ssl[sockindex];
794 struct ssl_backend_data *backend = connssl->backend;
795 mbedtls_pk_free(&backend->pk);
796 mbedtls_x509_crt_free(&backend->clicert);
797 mbedtls_x509_crt_free(&backend->cacert);
798 mbedtls_x509_crl_free(&backend->crl);
799 mbedtls_ssl_config_free(&backend->config);
800 mbedtls_ssl_free(&backend->ssl);
801 mbedtls_ctr_drbg_free(&backend->ctr_drbg);
802 #ifndef THREADING_SUPPORT
803 mbedtls_entropy_free(&backend->entropy);
804 #endif /* THREADING_SUPPORT */
805 }
806
mbed_recv(struct connectdata * conn,int num,char * buf,size_t buffersize,CURLcode * curlcode)807 static ssize_t mbed_recv(struct connectdata *conn, int num,
808 char *buf, size_t buffersize,
809 CURLcode *curlcode)
810 {
811 struct ssl_connect_data *connssl = &conn->ssl[num];
812 struct ssl_backend_data *backend = connssl->backend;
813 int ret = -1;
814 ssize_t len = -1;
815
816 memset(buf, 0, buffersize);
817 ret = mbedtls_ssl_read(&backend->ssl, (unsigned char *)buf,
818 buffersize);
819
820 if(ret <= 0) {
821 if(ret == MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY)
822 return 0;
823
824 *curlcode = (ret == MBEDTLS_ERR_SSL_WANT_READ) ?
825 CURLE_AGAIN : CURLE_RECV_ERROR;
826 return -1;
827 }
828
829 len = ret;
830
831 return len;
832 }
833
Curl_mbedtls_session_free(void * ptr)834 static void Curl_mbedtls_session_free(void *ptr)
835 {
836 mbedtls_ssl_session_free(ptr);
837 free(ptr);
838 }
839
Curl_mbedtls_version(char * buffer,size_t size)840 static size_t Curl_mbedtls_version(char *buffer, size_t size)
841 {
842 #ifdef MBEDTLS_VERSION_C
843 /* if mbedtls_version_get_number() is available it is better */
844 unsigned int version = mbedtls_version_get_number();
845 return msnprintf(buffer, size, "mbedTLS/%u.%u.%u", version>>24,
846 (version>>16)&0xff, (version>>8)&0xff);
847 #else
848 return msnprintf(buffer, size, "mbedTLS/%s", MBEDTLS_VERSION_STRING);
849 #endif
850 }
851
Curl_mbedtls_random(struct Curl_easy * data,unsigned char * entropy,size_t length)852 static CURLcode Curl_mbedtls_random(struct Curl_easy *data,
853 unsigned char *entropy, size_t length)
854 {
855 #if defined(MBEDTLS_CTR_DRBG_C)
856 int ret = -1;
857 char errorbuf[128];
858 mbedtls_entropy_context ctr_entropy;
859 mbedtls_ctr_drbg_context ctr_drbg;
860 mbedtls_entropy_init(&ctr_entropy);
861 mbedtls_ctr_drbg_init(&ctr_drbg);
862 errorbuf[0] = 0;
863
864 ret = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func,
865 &ctr_entropy, NULL, 0);
866
867 if(ret) {
868 #ifdef MBEDTLS_ERROR_C
869 mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
870 #endif /* MBEDTLS_ERROR_C */
871 failf(data, "Failed - mbedTLS: ctr_drbg_seed returned (-0x%04X) %s\n",
872 -ret, errorbuf);
873 }
874 else {
875 ret = mbedtls_ctr_drbg_random(&ctr_drbg, entropy, length);
876
877 if(ret) {
878 #ifdef MBEDTLS_ERROR_C
879 mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
880 #endif /* MBEDTLS_ERROR_C */
881 failf(data, "mbedTLS: ctr_drbg_init returned (-0x%04X) %s\n",
882 -ret, errorbuf);
883 }
884 }
885
886 mbedtls_ctr_drbg_free(&ctr_drbg);
887 mbedtls_entropy_free(&ctr_entropy);
888
889 return ret == 0 ? CURLE_OK : CURLE_FAILED_INIT;
890 #elif defined(MBEDTLS_HAVEGE_C)
891 mbedtls_havege_state hs;
892 mbedtls_havege_init(&hs);
893 mbedtls_havege_random(&hs, entropy, length);
894 mbedtls_havege_free(&hs);
895 return CURLE_OK;
896 #else
897 return CURLE_NOT_BUILT_IN;
898 #endif
899 }
900
901 static CURLcode
mbed_connect_common(struct connectdata * conn,int sockindex,bool nonblocking,bool * done)902 mbed_connect_common(struct connectdata *conn,
903 int sockindex,
904 bool nonblocking,
905 bool *done)
906 {
907 CURLcode retcode;
908 struct Curl_easy *data = conn->data;
909 struct ssl_connect_data *connssl = &conn->ssl[sockindex];
910 curl_socket_t sockfd = conn->sock[sockindex];
911 timediff_t timeout_ms;
912 int what;
913
914 /* check if the connection has already been established */
915 if(ssl_connection_complete == connssl->state) {
916 *done = TRUE;
917 return CURLE_OK;
918 }
919
920 if(ssl_connect_1 == connssl->connecting_state) {
921 /* Find out how much more time we're allowed */
922 timeout_ms = Curl_timeleft(data, NULL, TRUE);
923
924 if(timeout_ms < 0) {
925 /* no need to continue if time already is up */
926 failf(data, "SSL connection timeout");
927 return CURLE_OPERATION_TIMEDOUT;
928 }
929 retcode = mbed_connect_step1(conn, sockindex);
930 if(retcode)
931 return retcode;
932 }
933
934 while(ssl_connect_2 == connssl->connecting_state ||
935 ssl_connect_2_reading == connssl->connecting_state ||
936 ssl_connect_2_writing == connssl->connecting_state) {
937
938 /* check allowed time left */
939 timeout_ms = Curl_timeleft(data, NULL, TRUE);
940
941 if(timeout_ms < 0) {
942 /* no need to continue if time already is up */
943 failf(data, "SSL connection timeout");
944 return CURLE_OPERATION_TIMEDOUT;
945 }
946
947 /* if ssl is expecting something, check if it's available. */
948 if(connssl->connecting_state == ssl_connect_2_reading
949 || connssl->connecting_state == ssl_connect_2_writing) {
950
951 curl_socket_t writefd = ssl_connect_2_writing ==
952 connssl->connecting_state?sockfd:CURL_SOCKET_BAD;
953 curl_socket_t readfd = ssl_connect_2_reading ==
954 connssl->connecting_state?sockfd:CURL_SOCKET_BAD;
955
956 what = Curl_socket_check(readfd, CURL_SOCKET_BAD, writefd,
957 nonblocking ? 0 : timeout_ms);
958 if(what < 0) {
959 /* fatal error */
960 failf(data, "select/poll on SSL socket, errno: %d", SOCKERRNO);
961 return CURLE_SSL_CONNECT_ERROR;
962 }
963 else if(0 == what) {
964 if(nonblocking) {
965 *done = FALSE;
966 return CURLE_OK;
967 }
968 else {
969 /* timeout */
970 failf(data, "SSL connection timeout");
971 return CURLE_OPERATION_TIMEDOUT;
972 }
973 }
974 /* socket is readable or writable */
975 }
976
977 /* Run transaction, and return to the caller if it failed or if
978 * this connection is part of a multi handle and this loop would
979 * execute again. This permits the owner of a multi handle to
980 * abort a connection attempt before step2 has completed while
981 * ensuring that a client using select() or epoll() will always
982 * have a valid fdset to wait on.
983 */
984 retcode = mbed_connect_step2(conn, sockindex);
985 if(retcode || (nonblocking &&
986 (ssl_connect_2 == connssl->connecting_state ||
987 ssl_connect_2_reading == connssl->connecting_state ||
988 ssl_connect_2_writing == connssl->connecting_state)))
989 return retcode;
990
991 } /* repeat step2 until all transactions are done. */
992
993 if(ssl_connect_3 == connssl->connecting_state) {
994 retcode = mbed_connect_step3(conn, sockindex);
995 if(retcode)
996 return retcode;
997 }
998
999 if(ssl_connect_done == connssl->connecting_state) {
1000 connssl->state = ssl_connection_complete;
1001 conn->recv[sockindex] = mbed_recv;
1002 conn->send[sockindex] = mbed_send;
1003 *done = TRUE;
1004 }
1005 else
1006 *done = FALSE;
1007
1008 /* Reset our connect state machine */
1009 connssl->connecting_state = ssl_connect_1;
1010
1011 return CURLE_OK;
1012 }
1013
Curl_mbedtls_connect_nonblocking(struct connectdata * conn,int sockindex,bool * done)1014 static CURLcode Curl_mbedtls_connect_nonblocking(struct connectdata *conn,
1015 int sockindex, bool *done)
1016 {
1017 return mbed_connect_common(conn, sockindex, TRUE, done);
1018 }
1019
1020
Curl_mbedtls_connect(struct connectdata * conn,int sockindex)1021 static CURLcode Curl_mbedtls_connect(struct connectdata *conn, int sockindex)
1022 {
1023 CURLcode retcode;
1024 bool done = FALSE;
1025
1026 retcode = mbed_connect_common(conn, sockindex, FALSE, &done);
1027 if(retcode)
1028 return retcode;
1029
1030 DEBUGASSERT(done);
1031
1032 return CURLE_OK;
1033 }
1034
1035 /*
1036 * return 0 error initializing SSL
1037 * return 1 SSL initialized successfully
1038 */
Curl_mbedtls_init(void)1039 static int Curl_mbedtls_init(void)
1040 {
1041 return Curl_mbedtlsthreadlock_thread_setup();
1042 }
1043
Curl_mbedtls_cleanup(void)1044 static void Curl_mbedtls_cleanup(void)
1045 {
1046 (void)Curl_mbedtlsthreadlock_thread_cleanup();
1047 }
1048
Curl_mbedtls_data_pending(const struct connectdata * conn,int sockindex)1049 static bool Curl_mbedtls_data_pending(const struct connectdata *conn,
1050 int sockindex)
1051 {
1052 const struct ssl_connect_data *connssl = &conn->ssl[sockindex];
1053 struct ssl_backend_data *backend = connssl->backend;
1054 return mbedtls_ssl_get_bytes_avail(&backend->ssl) != 0;
1055 }
1056
Curl_mbedtls_sha256sum(const unsigned char * input,size_t inputlen,unsigned char * sha256sum,size_t sha256len UNUSED_PARAM)1057 static CURLcode Curl_mbedtls_sha256sum(const unsigned char *input,
1058 size_t inputlen,
1059 unsigned char *sha256sum,
1060 size_t sha256len UNUSED_PARAM)
1061 {
1062 (void)sha256len;
1063 #if MBEDTLS_VERSION_NUMBER < 0x02070000
1064 mbedtls_sha256(input, inputlen, sha256sum, 0);
1065 #else
1066 /* returns 0 on success, otherwise failure */
1067 if(mbedtls_sha256_ret(input, inputlen, sha256sum, 0) != 0)
1068 return CURLE_BAD_FUNCTION_ARGUMENT;
1069 #endif
1070 return CURLE_OK;
1071 }
1072
Curl_mbedtls_get_internals(struct ssl_connect_data * connssl,CURLINFO info UNUSED_PARAM)1073 static void *Curl_mbedtls_get_internals(struct ssl_connect_data *connssl,
1074 CURLINFO info UNUSED_PARAM)
1075 {
1076 struct ssl_backend_data *backend = connssl->backend;
1077 (void)info;
1078 return &backend->ssl;
1079 }
1080
1081 const struct Curl_ssl Curl_ssl_mbedtls = {
1082 { CURLSSLBACKEND_MBEDTLS, "mbedtls" }, /* info */
1083
1084 SSLSUPP_CA_PATH |
1085 SSLSUPP_PINNEDPUBKEY |
1086 SSLSUPP_SSL_CTX,
1087
1088 sizeof(struct ssl_backend_data),
1089
1090 Curl_mbedtls_init, /* init */
1091 Curl_mbedtls_cleanup, /* cleanup */
1092 Curl_mbedtls_version, /* version */
1093 Curl_none_check_cxn, /* check_cxn */
1094 Curl_none_shutdown, /* shutdown */
1095 Curl_mbedtls_data_pending, /* data_pending */
1096 Curl_mbedtls_random, /* random */
1097 Curl_none_cert_status_request, /* cert_status_request */
1098 Curl_mbedtls_connect, /* connect */
1099 Curl_mbedtls_connect_nonblocking, /* connect_nonblocking */
1100 Curl_mbedtls_get_internals, /* get_internals */
1101 Curl_mbedtls_close, /* close_one */
1102 Curl_mbedtls_close_all, /* close_all */
1103 Curl_mbedtls_session_free, /* session_free */
1104 Curl_none_set_engine, /* set_engine */
1105 Curl_none_set_engine_default, /* set_engine_default */
1106 Curl_none_engines_list, /* engines_list */
1107 Curl_none_false_start, /* false_start */
1108 Curl_none_md5sum, /* md5sum */
1109 Curl_mbedtls_sha256sum /* sha256sum */
1110 };
1111
1112 #endif /* USE_MBEDTLS */
1113