1 /*
2 * TLSv1 client - write handshake message
3 * Copyright (c) 2006-2015, Jouni Malinen <j@w1.fi>
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9 #include "includes.h"
10
11 #include "common.h"
12 #include "crypto/md5.h"
13 #include "crypto/sha1.h"
14 #include "crypto/sha256.h"
15 #include "crypto/tls.h"
16 #include "crypto/random.h"
17 #include "x509v3.h"
18 #include "tlsv1_common.h"
19 #include "tlsv1_record.h"
20 #include "tlsv1_client.h"
21 #include "tlsv1_client_i.h"
22
23
tls_client_cert_chain_der_len(struct tlsv1_client * conn)24 static size_t tls_client_cert_chain_der_len(struct tlsv1_client *conn)
25 {
26 size_t len = 0;
27 struct x509_certificate *cert;
28
29 if (conn->cred == NULL)
30 return 0;
31
32 cert = conn->cred->cert;
33 while (cert) {
34 len += 3 + cert->cert_len;
35 if (x509_certificate_self_signed(cert))
36 break;
37 cert = x509_certificate_get_subject(conn->cred->trusted_certs,
38 &cert->issuer);
39 }
40
41 return len;
42 }
43
44
tls_send_client_hello(struct tlsv1_client * conn,size_t * out_len)45 u8 * tls_send_client_hello(struct tlsv1_client *conn, size_t *out_len)
46 {
47 u8 *hello, *end, *pos, *hs_length, *hs_start, *rhdr;
48 struct os_time now;
49 size_t len, i;
50 u8 *ext_start;
51 u16 tls_version = TLS_VERSION;
52
53 /* Pick the highest locally enabled TLS version */
54 #ifdef CONFIG_TLSV12
55 if ((conn->flags & TLS_CONN_DISABLE_TLSv1_2) &&
56 tls_version == TLS_VERSION_1_2)
57 tls_version = TLS_VERSION_1_1;
58 #endif /* CONFIG_TLSV12 */
59 #ifdef CONFIG_TLSV11
60 if ((conn->flags & TLS_CONN_DISABLE_TLSv1_1) &&
61 tls_version == TLS_VERSION_1_1)
62 tls_version = TLS_VERSION_1;
63 #endif /* CONFIG_TLSV11 */
64 if ((conn->flags & TLS_CONN_DISABLE_TLSv1_0) &&
65 tls_version == TLS_VERSION_1) {
66 wpa_printf(MSG_INFO, "TLSv1: No TLS version allowed");
67 return NULL;
68 }
69
70 wpa_printf(MSG_DEBUG, "TLSv1: Send ClientHello (ver %s)",
71 tls_version_str(tls_version));
72 *out_len = 0;
73
74 os_get_time(&now);
75 #ifdef TEST_FUZZ
76 now.sec = 0xfffefdfc;
77 #endif /* TEST_FUZZ */
78 WPA_PUT_BE32(conn->client_random, now.sec);
79 if (random_get_bytes(conn->client_random + 4, TLS_RANDOM_LEN - 4)) {
80 wpa_printf(MSG_ERROR, "TLSv1: Could not generate "
81 "client_random");
82 return NULL;
83 }
84 wpa_hexdump(MSG_MSGDUMP, "TLSv1: client_random",
85 conn->client_random, TLS_RANDOM_LEN);
86
87 len = 150 + conn->num_cipher_suites * 2 + conn->client_hello_ext_len;
88 hello = os_malloc(len);
89 if (hello == NULL)
90 return NULL;
91 end = hello + len;
92
93 rhdr = hello;
94 pos = rhdr + TLS_RECORD_HEADER_LEN;
95
96 /* opaque fragment[TLSPlaintext.length] */
97
98 /* Handshake */
99 hs_start = pos;
100 /* HandshakeType msg_type */
101 *pos++ = TLS_HANDSHAKE_TYPE_CLIENT_HELLO;
102 /* uint24 length (to be filled) */
103 hs_length = pos;
104 pos += 3;
105 /* body - ClientHello */
106 /* ProtocolVersion client_version */
107 WPA_PUT_BE16(pos, tls_version);
108 pos += 2;
109 /* Random random: uint32 gmt_unix_time, opaque random_bytes */
110 os_memcpy(pos, conn->client_random, TLS_RANDOM_LEN);
111 pos += TLS_RANDOM_LEN;
112 /* SessionID session_id */
113 *pos++ = conn->session_id_len;
114 os_memcpy(pos, conn->session_id, conn->session_id_len);
115 pos += conn->session_id_len;
116 /* CipherSuite cipher_suites<2..2^16-1> */
117 WPA_PUT_BE16(pos, 2 * conn->num_cipher_suites);
118 pos += 2;
119 for (i = 0; i < conn->num_cipher_suites; i++) {
120 WPA_PUT_BE16(pos, conn->cipher_suites[i]);
121 pos += 2;
122 }
123 /* CompressionMethod compression_methods<1..2^8-1> */
124 *pos++ = 1;
125 *pos++ = TLS_COMPRESSION_NULL;
126
127 /* Extension */
128 ext_start = pos;
129 pos += 2;
130
131 #ifdef CONFIG_TLSV12
132 if (conn->rl.tls_version >= TLS_VERSION_1_2) {
133 /*
134 * Add signature_algorithms extension since we support only
135 * SHA256 (and not the default SHA1) with TLSv1.2.
136 */
137 /* ExtensionsType extension_type = signature_algorithms(13) */
138 WPA_PUT_BE16(pos, TLS_EXT_SIGNATURE_ALGORITHMS);
139 pos += 2;
140 /* opaque extension_data<0..2^16-1> length */
141 WPA_PUT_BE16(pos, 8);
142 pos += 2;
143 /* supported_signature_algorithms<2..2^16-2> length */
144 WPA_PUT_BE16(pos, 6);
145 pos += 2;
146 /* supported_signature_algorithms */
147 *pos++ = TLS_HASH_ALG_SHA512;
148 *pos++ = TLS_SIGN_ALG_RSA;
149 *pos++ = TLS_HASH_ALG_SHA384;
150 *pos++ = TLS_SIGN_ALG_RSA;
151 *pos++ = TLS_HASH_ALG_SHA256;
152 *pos++ = TLS_SIGN_ALG_RSA;
153 }
154 #endif /* CONFIG_TLSV12 */
155
156 if (conn->client_hello_ext) {
157 os_memcpy(pos, conn->client_hello_ext,
158 conn->client_hello_ext_len);
159 pos += conn->client_hello_ext_len;
160 }
161
162 if (conn->flags & TLS_CONN_REQUEST_OCSP) {
163 wpa_printf(MSG_DEBUG,
164 "TLSv1: Add status_request extension for OCSP stapling");
165 /* ExtensionsType extension_type = status_request(5) */
166 WPA_PUT_BE16(pos, TLS_EXT_STATUS_REQUEST);
167 pos += 2;
168 /* opaque extension_data<0..2^16-1> length */
169 WPA_PUT_BE16(pos, 5);
170 pos += 2;
171
172 /*
173 * RFC 6066, 8:
174 * struct {
175 * CertificateStatusType status_type;
176 * select (status_type) {
177 * case ocsp: OCSPStatusRequest;
178 * } request;
179 * } CertificateStatusRequest;
180 *
181 * enum { ocsp(1), (255) } CertificateStatusType;
182 */
183 *pos++ = 1; /* status_type = ocsp(1) */
184
185 /*
186 * struct {
187 * ResponderID responder_id_list<0..2^16-1>;
188 * Extensions request_extensions;
189 * } OCSPStatusRequest;
190 *
191 * opaque ResponderID<1..2^16-1>;
192 * opaque Extensions<0..2^16-1>;
193 */
194 WPA_PUT_BE16(pos, 0); /* responder_id_list(empty) */
195 pos += 2;
196 WPA_PUT_BE16(pos, 0); /* request_extensions(empty) */
197 pos += 2;
198
199 wpa_printf(MSG_DEBUG,
200 "TLSv1: Add status_request_v2 extension for OCSP stapling");
201 /* ExtensionsType extension_type = status_request_v2(17) */
202 WPA_PUT_BE16(pos, TLS_EXT_STATUS_REQUEST_V2);
203 pos += 2;
204 /* opaque extension_data<0..2^16-1> length */
205 WPA_PUT_BE16(pos, 7);
206 pos += 2;
207
208 /*
209 * RFC 6961, 2.2:
210 * struct {
211 * CertificateStatusType status_type;
212 * uint16 request_length;
213 * select (status_type) {
214 * case ocsp: OCSPStatusRequest;
215 * case ocsp_multi: OCSPStatusRequest;
216 * } request;
217 * } CertificateStatusRequestItemV2;
218 *
219 * enum { ocsp(1), ocsp_multi(2), (255) } CertificateStatusType;
220 *
221 * struct {
222 * CertificateStatusRequestItemV2
223 * certificate_status_req_list<1..2^16-1>;
224 * } CertificateStatusRequestListV2;
225 */
226
227 /* certificate_status_req_list<1..2^16-1> */
228 WPA_PUT_BE16(pos, 5);
229 pos += 2;
230
231 /* CertificateStatusRequestItemV2 */
232 *pos++ = 2; /* status_type = ocsp_multi(2) */
233 /* OCSPStatusRequest as shown above for v1 */
234 WPA_PUT_BE16(pos, 0); /* responder_id_list(empty) */
235 pos += 2;
236 WPA_PUT_BE16(pos, 0); /* request_extensions(empty) */
237 pos += 2;
238 }
239
240 if (pos == ext_start + 2)
241 pos -= 2; /* no extensions */
242 else
243 WPA_PUT_BE16(ext_start, pos - ext_start - 2);
244
245 WPA_PUT_BE24(hs_length, pos - hs_length - 3);
246 tls_verify_hash_add(&conn->verify, hs_start, pos - hs_start);
247
248 if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_HANDSHAKE,
249 rhdr, end - rhdr, hs_start, pos - hs_start,
250 out_len) < 0) {
251 wpa_printf(MSG_DEBUG, "TLSv1: Failed to create TLS record");
252 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
253 TLS_ALERT_INTERNAL_ERROR);
254 os_free(hello);
255 return NULL;
256 }
257
258 conn->state = SERVER_HELLO;
259
260 return hello;
261 }
262
263
tls_write_client_certificate(struct tlsv1_client * conn,u8 ** msgpos,u8 * end)264 static int tls_write_client_certificate(struct tlsv1_client *conn,
265 u8 **msgpos, u8 *end)
266 {
267 u8 *pos, *rhdr, *hs_start, *hs_length, *cert_start;
268 size_t rlen;
269 struct x509_certificate *cert;
270
271 pos = *msgpos;
272 if (TLS_RECORD_HEADER_LEN + 1 + 3 + 3 > end - pos) {
273 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
274 TLS_ALERT_INTERNAL_ERROR);
275 return -1;
276 }
277
278 wpa_printf(MSG_DEBUG, "TLSv1: Send Certificate");
279 rhdr = pos;
280 pos += TLS_RECORD_HEADER_LEN;
281
282 /* opaque fragment[TLSPlaintext.length] */
283
284 /* Handshake */
285 hs_start = pos;
286 /* HandshakeType msg_type */
287 *pos++ = TLS_HANDSHAKE_TYPE_CERTIFICATE;
288 /* uint24 length (to be filled) */
289 hs_length = pos;
290 pos += 3;
291 /* body - Certificate */
292 /* uint24 length (to be filled) */
293 cert_start = pos;
294 pos += 3;
295 cert = conn->cred ? conn->cred->cert : NULL;
296 while (cert) {
297 if (3 + cert->cert_len > (size_t) (end - pos)) {
298 wpa_printf(MSG_DEBUG, "TLSv1: Not enough buffer space "
299 "for Certificate (cert_len=%lu left=%lu)",
300 (unsigned long) cert->cert_len,
301 (unsigned long) (end - pos));
302 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
303 TLS_ALERT_INTERNAL_ERROR);
304 return -1;
305 }
306 WPA_PUT_BE24(pos, cert->cert_len);
307 pos += 3;
308 os_memcpy(pos, cert->cert_start, cert->cert_len);
309 pos += cert->cert_len;
310
311 if (x509_certificate_self_signed(cert))
312 break;
313 cert = x509_certificate_get_subject(conn->cred->trusted_certs,
314 &cert->issuer);
315 }
316 if (conn->cred == NULL || cert == conn->cred->cert || cert == NULL) {
317 /*
318 * Client was not configured with all the needed certificates
319 * to form a full certificate chain. The server may fail to
320 * validate the chain unless it is configured with all the
321 * missing CA certificates.
322 */
323 wpa_printf(MSG_DEBUG, "TLSv1: Full client certificate chain "
324 "not configured - validation may fail");
325 }
326 WPA_PUT_BE24(cert_start, pos - cert_start - 3);
327
328 WPA_PUT_BE24(hs_length, pos - hs_length - 3);
329
330 if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_HANDSHAKE,
331 rhdr, end - rhdr, hs_start, pos - hs_start,
332 &rlen) < 0) {
333 wpa_printf(MSG_DEBUG, "TLSv1: Failed to generate a record");
334 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
335 TLS_ALERT_INTERNAL_ERROR);
336 return -1;
337 }
338 pos = rhdr + rlen;
339
340 tls_verify_hash_add(&conn->verify, hs_start, pos - hs_start);
341
342 *msgpos = pos;
343
344 return 0;
345 }
346
347
tlsv1_key_x_dh(struct tlsv1_client * conn,u8 ** pos,u8 * end)348 static int tlsv1_key_x_dh(struct tlsv1_client *conn, u8 **pos, u8 *end)
349 {
350 /* ClientDiffieHellmanPublic */
351 u8 *csecret, *csecret_start, *dh_yc, *shared;
352 size_t csecret_len, dh_yc_len, shared_len;
353
354 csecret_len = conn->dh_p_len;
355 csecret = os_malloc(csecret_len);
356 if (csecret == NULL) {
357 wpa_printf(MSG_DEBUG, "TLSv1: Failed to allocate "
358 "memory for Yc (Diffie-Hellman)");
359 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
360 TLS_ALERT_INTERNAL_ERROR);
361 return -1;
362 }
363 if (random_get_bytes(csecret, csecret_len)) {
364 wpa_printf(MSG_DEBUG, "TLSv1: Failed to get random "
365 "data for Diffie-Hellman");
366 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
367 TLS_ALERT_INTERNAL_ERROR);
368 os_free(csecret);
369 return -1;
370 }
371
372 if (os_memcmp(csecret, conn->dh_p, csecret_len) > 0)
373 csecret[0] = 0; /* make sure Yc < p */
374
375 csecret_start = csecret;
376 while (csecret_len > 1 && *csecret_start == 0) {
377 csecret_start++;
378 csecret_len--;
379 }
380 wpa_hexdump_key(MSG_DEBUG, "TLSv1: DH client's secret value",
381 csecret_start, csecret_len);
382
383 /* Yc = g^csecret mod p */
384 dh_yc_len = conn->dh_p_len;
385 dh_yc = os_malloc(dh_yc_len);
386 if (dh_yc == NULL) {
387 wpa_printf(MSG_DEBUG, "TLSv1: Failed to allocate "
388 "memory for Diffie-Hellman");
389 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
390 TLS_ALERT_INTERNAL_ERROR);
391 os_free(csecret);
392 return -1;
393 }
394 if (crypto_mod_exp(conn->dh_g, conn->dh_g_len,
395 csecret_start, csecret_len,
396 conn->dh_p, conn->dh_p_len,
397 dh_yc, &dh_yc_len)) {
398 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
399 TLS_ALERT_INTERNAL_ERROR);
400 os_free(csecret);
401 os_free(dh_yc);
402 return -1;
403 }
404
405 wpa_hexdump(MSG_DEBUG, "TLSv1: DH Yc (client's public value)",
406 dh_yc, dh_yc_len);
407
408 if (end - *pos < 2) {
409 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
410 TLS_ALERT_INTERNAL_ERROR);
411 os_free(csecret);
412 os_free(dh_yc);
413 return -1;
414 }
415 WPA_PUT_BE16(*pos, dh_yc_len);
416 *pos += 2;
417 if (dh_yc_len > (size_t) (end - *pos)) {
418 wpa_printf(MSG_DEBUG, "TLSv1: Not enough room in the "
419 "message buffer for Yc");
420 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
421 TLS_ALERT_INTERNAL_ERROR);
422 os_free(csecret);
423 os_free(dh_yc);
424 return -1;
425 }
426 os_memcpy(*pos, dh_yc, dh_yc_len);
427 *pos += dh_yc_len;
428 os_free(dh_yc);
429
430 shared_len = conn->dh_p_len;
431 shared = os_malloc(shared_len);
432 if (shared == NULL) {
433 wpa_printf(MSG_DEBUG, "TLSv1: Could not allocate memory for "
434 "DH");
435 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
436 TLS_ALERT_INTERNAL_ERROR);
437 os_free(csecret);
438 return -1;
439 }
440
441 /* shared = Ys^csecret mod p */
442 if (crypto_mod_exp(conn->dh_ys, conn->dh_ys_len,
443 csecret_start, csecret_len,
444 conn->dh_p, conn->dh_p_len,
445 shared, &shared_len)) {
446 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
447 TLS_ALERT_INTERNAL_ERROR);
448 os_free(csecret);
449 os_free(shared);
450 return -1;
451 }
452 wpa_hexdump_key(MSG_DEBUG, "TLSv1: Shared secret from DH key exchange",
453 shared, shared_len);
454
455 os_memset(csecret_start, 0, csecret_len);
456 os_free(csecret);
457 if (tls_derive_keys(conn, shared, shared_len)) {
458 wpa_printf(MSG_DEBUG, "TLSv1: Failed to derive keys");
459 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
460 TLS_ALERT_INTERNAL_ERROR);
461 os_free(shared);
462 return -1;
463 }
464 os_memset(shared, 0, shared_len);
465 os_free(shared);
466 tlsv1_client_free_dh(conn);
467 return 0;
468 }
469
470
tlsv1_key_x_rsa(struct tlsv1_client * conn,u8 ** pos,u8 * end)471 static int tlsv1_key_x_rsa(struct tlsv1_client *conn, u8 **pos, u8 *end)
472 {
473 u8 pre_master_secret[TLS_PRE_MASTER_SECRET_LEN];
474 size_t clen;
475 int res;
476
477 if (tls_derive_pre_master_secret(pre_master_secret) < 0 ||
478 tls_derive_keys(conn, pre_master_secret,
479 TLS_PRE_MASTER_SECRET_LEN)) {
480 wpa_printf(MSG_DEBUG, "TLSv1: Failed to derive keys");
481 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
482 TLS_ALERT_INTERNAL_ERROR);
483 return -1;
484 }
485
486 /* EncryptedPreMasterSecret */
487 if (conn->server_rsa_key == NULL) {
488 wpa_printf(MSG_DEBUG, "TLSv1: No server RSA key to "
489 "use for encrypting pre-master secret");
490 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
491 TLS_ALERT_INTERNAL_ERROR);
492 return -1;
493 }
494
495 /* RSA encrypted value is encoded with PKCS #1 v1.5 block type 2. */
496 *pos += 2;
497 clen = end - *pos;
498 res = crypto_public_key_encrypt_pkcs1_v15(
499 conn->server_rsa_key,
500 pre_master_secret, TLS_PRE_MASTER_SECRET_LEN,
501 *pos, &clen);
502 os_memset(pre_master_secret, 0, TLS_PRE_MASTER_SECRET_LEN);
503 if (res < 0) {
504 wpa_printf(MSG_DEBUG, "TLSv1: RSA encryption failed");
505 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
506 TLS_ALERT_INTERNAL_ERROR);
507 return -1;
508 }
509 WPA_PUT_BE16(*pos - 2, clen);
510 wpa_hexdump(MSG_MSGDUMP, "TLSv1: Encrypted pre_master_secret",
511 *pos, clen);
512 *pos += clen;
513
514 return 0;
515 }
516
517
tls_write_client_key_exchange(struct tlsv1_client * conn,u8 ** msgpos,u8 * end)518 static int tls_write_client_key_exchange(struct tlsv1_client *conn,
519 u8 **msgpos, u8 *end)
520 {
521 u8 *pos, *rhdr, *hs_start, *hs_length;
522 size_t rlen;
523 tls_key_exchange keyx;
524 const struct tls_cipher_suite *suite;
525
526 suite = tls_get_cipher_suite(conn->rl.cipher_suite);
527 if (suite == NULL)
528 keyx = TLS_KEY_X_NULL;
529 else
530 keyx = suite->key_exchange;
531
532 pos = *msgpos;
533
534 wpa_printf(MSG_DEBUG, "TLSv1: Send ClientKeyExchange");
535
536 rhdr = pos;
537 pos += TLS_RECORD_HEADER_LEN;
538
539 /* opaque fragment[TLSPlaintext.length] */
540
541 /* Handshake */
542 hs_start = pos;
543 /* HandshakeType msg_type */
544 *pos++ = TLS_HANDSHAKE_TYPE_CLIENT_KEY_EXCHANGE;
545 /* uint24 length (to be filled) */
546 hs_length = pos;
547 pos += 3;
548 /* body - ClientKeyExchange */
549 if (keyx == TLS_KEY_X_DH_anon || keyx == TLS_KEY_X_DHE_RSA) {
550 if (tlsv1_key_x_dh(conn, &pos, end) < 0)
551 return -1;
552 } else {
553 if (tlsv1_key_x_rsa(conn, &pos, end) < 0)
554 return -1;
555 }
556
557 WPA_PUT_BE24(hs_length, pos - hs_length - 3);
558
559 if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_HANDSHAKE,
560 rhdr, end - rhdr, hs_start, pos - hs_start,
561 &rlen) < 0) {
562 wpa_printf(MSG_DEBUG, "TLSv1: Failed to create a record");
563 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
564 TLS_ALERT_INTERNAL_ERROR);
565 return -1;
566 }
567 pos = rhdr + rlen;
568 tls_verify_hash_add(&conn->verify, hs_start, pos - hs_start);
569
570 *msgpos = pos;
571
572 return 0;
573 }
574
575
tls_write_client_certificate_verify(struct tlsv1_client * conn,u8 ** msgpos,u8 * end)576 static int tls_write_client_certificate_verify(struct tlsv1_client *conn,
577 u8 **msgpos, u8 *end)
578 {
579 u8 *pos, *rhdr, *hs_start, *hs_length, *signed_start;
580 size_t rlen, hlen, clen;
581 u8 hash[100], *hpos;
582
583 pos = *msgpos;
584
585 wpa_printf(MSG_DEBUG, "TLSv1: Send CertificateVerify");
586 rhdr = pos;
587 pos += TLS_RECORD_HEADER_LEN;
588
589 /* Handshake */
590 hs_start = pos;
591 /* HandshakeType msg_type */
592 *pos++ = TLS_HANDSHAKE_TYPE_CERTIFICATE_VERIFY;
593 /* uint24 length (to be filled) */
594 hs_length = pos;
595 pos += 3;
596
597 /*
598 * RFC 2246: 7.4.3 and 7.4.8:
599 * Signature signature
600 *
601 * RSA:
602 * digitally-signed struct {
603 * opaque md5_hash[16];
604 * opaque sha_hash[20];
605 * };
606 *
607 * DSA:
608 * digitally-signed struct {
609 * opaque sha_hash[20];
610 * };
611 *
612 * The hash values are calculated over all handshake messages sent or
613 * received starting at ClientHello up to, but not including, this
614 * CertificateVerify message, including the type and length fields of
615 * the handshake messages.
616 */
617
618 hpos = hash;
619
620 #ifdef CONFIG_TLSV12
621 if (conn->rl.tls_version == TLS_VERSION_1_2) {
622 hlen = SHA256_MAC_LEN;
623 if (conn->verify.sha256_cert == NULL ||
624 crypto_hash_finish(conn->verify.sha256_cert, hpos, &hlen) <
625 0) {
626 conn->verify.sha256_cert = NULL;
627 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
628 TLS_ALERT_INTERNAL_ERROR);
629 return -1;
630 }
631 conn->verify.sha256_cert = NULL;
632
633 /*
634 * RFC 3447, A.2.4 RSASSA-PKCS1-v1_5
635 *
636 * DigestInfo ::= SEQUENCE {
637 * digestAlgorithm DigestAlgorithm,
638 * digest OCTET STRING
639 * }
640 *
641 * SHA-256 OID: sha256WithRSAEncryption ::= {pkcs-1 11}
642 *
643 * DER encoded DigestInfo for SHA256 per RFC 3447:
644 * 30 31 30 0d 06 09 60 86 48 01 65 03 04 02 01 05 00 04 20 ||
645 * H
646 */
647 os_memmove(hash + 19, hash, hlen);
648 hlen += 19;
649 os_memcpy(hash, "\x30\x31\x30\x0d\x06\x09\x60\x86\x48\x01\x65"
650 "\x03\x04\x02\x01\x05\x00\x04\x20", 19);
651 } else {
652 #endif /* CONFIG_TLSV12 */
653
654 hlen = MD5_MAC_LEN;
655 if (conn->verify.md5_cert == NULL ||
656 crypto_hash_finish(conn->verify.md5_cert, hpos, &hlen) < 0) {
657 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
658 TLS_ALERT_INTERNAL_ERROR);
659 conn->verify.md5_cert = NULL;
660 crypto_hash_finish(conn->verify.sha1_cert, NULL, NULL);
661 conn->verify.sha1_cert = NULL;
662 return -1;
663 }
664 hpos += MD5_MAC_LEN;
665
666 conn->verify.md5_cert = NULL;
667 hlen = SHA1_MAC_LEN;
668 if (conn->verify.sha1_cert == NULL ||
669 crypto_hash_finish(conn->verify.sha1_cert, hpos, &hlen) < 0) {
670 conn->verify.sha1_cert = NULL;
671 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
672 TLS_ALERT_INTERNAL_ERROR);
673 return -1;
674 }
675 conn->verify.sha1_cert = NULL;
676
677 hlen += MD5_MAC_LEN;
678
679 #ifdef CONFIG_TLSV12
680 }
681 #endif /* CONFIG_TLSV12 */
682
683 wpa_hexdump(MSG_MSGDUMP, "TLSv1: CertificateVerify hash", hash, hlen);
684
685 #ifdef CONFIG_TLSV12
686 if (conn->rl.tls_version >= TLS_VERSION_1_2) {
687 /*
688 * RFC 5246, 4.7:
689 * TLS v1.2 adds explicit indication of the used signature and
690 * hash algorithms.
691 *
692 * struct {
693 * HashAlgorithm hash;
694 * SignatureAlgorithm signature;
695 * } SignatureAndHashAlgorithm;
696 */
697 *pos++ = TLS_HASH_ALG_SHA256;
698 *pos++ = TLS_SIGN_ALG_RSA;
699 }
700 #endif /* CONFIG_TLSV12 */
701
702 /*
703 * RFC 2246, 4.7:
704 * In digital signing, one-way hash functions are used as input for a
705 * signing algorithm. A digitally-signed element is encoded as an
706 * opaque vector <0..2^16-1>, where the length is specified by the
707 * signing algorithm and key.
708 *
709 * In RSA signing, a 36-byte structure of two hashes (one SHA and one
710 * MD5) is signed (encrypted with the private key). It is encoded with
711 * PKCS #1 block type 0 or type 1 as described in [PKCS1].
712 */
713 signed_start = pos; /* length to be filled */
714 pos += 2;
715 clen = end - pos;
716 if (conn->cred == NULL ||
717 crypto_private_key_sign_pkcs1(conn->cred->key, hash, hlen,
718 pos, &clen) < 0) {
719 wpa_printf(MSG_DEBUG, "TLSv1: Failed to sign hash (PKCS #1)");
720 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
721 TLS_ALERT_INTERNAL_ERROR);
722 return -1;
723 }
724 WPA_PUT_BE16(signed_start, clen);
725
726 pos += clen;
727
728 WPA_PUT_BE24(hs_length, pos - hs_length - 3);
729
730 if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_HANDSHAKE,
731 rhdr, end - rhdr, hs_start, pos - hs_start,
732 &rlen) < 0) {
733 wpa_printf(MSG_DEBUG, "TLSv1: Failed to generate a record");
734 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
735 TLS_ALERT_INTERNAL_ERROR);
736 return -1;
737 }
738 pos = rhdr + rlen;
739
740 tls_verify_hash_add(&conn->verify, hs_start, pos - hs_start);
741
742 *msgpos = pos;
743
744 return 0;
745 }
746
747
tls_write_client_change_cipher_spec(struct tlsv1_client * conn,u8 ** msgpos,u8 * end)748 static int tls_write_client_change_cipher_spec(struct tlsv1_client *conn,
749 u8 **msgpos, u8 *end)
750 {
751 size_t rlen;
752 u8 payload[1];
753
754 wpa_printf(MSG_DEBUG, "TLSv1: Send ChangeCipherSpec");
755
756 payload[0] = TLS_CHANGE_CIPHER_SPEC;
757
758 if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_CHANGE_CIPHER_SPEC,
759 *msgpos, end - *msgpos, payload, sizeof(payload),
760 &rlen) < 0) {
761 wpa_printf(MSG_DEBUG, "TLSv1: Failed to create a record");
762 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
763 TLS_ALERT_INTERNAL_ERROR);
764 return -1;
765 }
766
767 if (tlsv1_record_change_write_cipher(&conn->rl) < 0) {
768 wpa_printf(MSG_DEBUG, "TLSv1: Failed to set write cipher for "
769 "record layer");
770 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
771 TLS_ALERT_INTERNAL_ERROR);
772 return -1;
773 }
774
775 *msgpos += rlen;
776
777 return 0;
778 }
779
780
tls_write_client_finished(struct tlsv1_client * conn,u8 ** msgpos,u8 * end)781 static int tls_write_client_finished(struct tlsv1_client *conn,
782 u8 **msgpos, u8 *end)
783 {
784 u8 *pos, *hs_start;
785 size_t rlen, hlen;
786 u8 verify_data[1 + 3 + TLS_VERIFY_DATA_LEN];
787 u8 hash[MD5_MAC_LEN + SHA1_MAC_LEN];
788
789 wpa_printf(MSG_DEBUG, "TLSv1: Send Finished");
790
791 /* Encrypted Handshake Message: Finished */
792
793 #ifdef CONFIG_TLSV12
794 if (conn->rl.tls_version >= TLS_VERSION_1_2) {
795 hlen = SHA256_MAC_LEN;
796 if (conn->verify.sha256_client == NULL ||
797 crypto_hash_finish(conn->verify.sha256_client, hash, &hlen)
798 < 0) {
799 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
800 TLS_ALERT_INTERNAL_ERROR);
801 conn->verify.sha256_client = NULL;
802 return -1;
803 }
804 conn->verify.sha256_client = NULL;
805 } else {
806 #endif /* CONFIG_TLSV12 */
807
808 hlen = MD5_MAC_LEN;
809 if (conn->verify.md5_client == NULL ||
810 crypto_hash_finish(conn->verify.md5_client, hash, &hlen) < 0) {
811 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
812 TLS_ALERT_INTERNAL_ERROR);
813 conn->verify.md5_client = NULL;
814 crypto_hash_finish(conn->verify.sha1_client, NULL, NULL);
815 conn->verify.sha1_client = NULL;
816 return -1;
817 }
818 conn->verify.md5_client = NULL;
819 hlen = SHA1_MAC_LEN;
820 if (conn->verify.sha1_client == NULL ||
821 crypto_hash_finish(conn->verify.sha1_client, hash + MD5_MAC_LEN,
822 &hlen) < 0) {
823 conn->verify.sha1_client = NULL;
824 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
825 TLS_ALERT_INTERNAL_ERROR);
826 return -1;
827 }
828 conn->verify.sha1_client = NULL;
829 hlen = MD5_MAC_LEN + SHA1_MAC_LEN;
830
831 #ifdef CONFIG_TLSV12
832 }
833 #endif /* CONFIG_TLSV12 */
834
835 if (tls_prf(conn->rl.tls_version,
836 conn->master_secret, TLS_MASTER_SECRET_LEN,
837 "client finished", hash, hlen,
838 verify_data + 1 + 3, TLS_VERIFY_DATA_LEN)) {
839 wpa_printf(MSG_DEBUG, "TLSv1: Failed to generate verify_data");
840 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
841 TLS_ALERT_INTERNAL_ERROR);
842 return -1;
843 }
844 wpa_hexdump_key(MSG_DEBUG, "TLSv1: verify_data (client)",
845 verify_data + 1 + 3, TLS_VERIFY_DATA_LEN);
846
847 /* Handshake */
848 pos = hs_start = verify_data;
849 /* HandshakeType msg_type */
850 *pos++ = TLS_HANDSHAKE_TYPE_FINISHED;
851 /* uint24 length */
852 WPA_PUT_BE24(pos, TLS_VERIFY_DATA_LEN);
853 pos += 3;
854 pos += TLS_VERIFY_DATA_LEN; /* verify_data already in place */
855 tls_verify_hash_add(&conn->verify, hs_start, pos - hs_start);
856
857 if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_HANDSHAKE,
858 *msgpos, end - *msgpos, hs_start, pos - hs_start,
859 &rlen) < 0) {
860 wpa_printf(MSG_DEBUG, "TLSv1: Failed to create a record");
861 tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
862 TLS_ALERT_INTERNAL_ERROR);
863 return -1;
864 }
865
866 *msgpos += rlen;
867
868 return 0;
869 }
870
871
tls_send_client_key_exchange(struct tlsv1_client * conn,size_t * out_len)872 static u8 * tls_send_client_key_exchange(struct tlsv1_client *conn,
873 size_t *out_len)
874 {
875 u8 *msg, *end, *pos;
876 size_t msglen;
877
878 *out_len = 0;
879
880 msglen = 2000;
881 if (conn->certificate_requested)
882 msglen += tls_client_cert_chain_der_len(conn);
883
884 msg = os_malloc(msglen);
885 if (msg == NULL)
886 return NULL;
887
888 pos = msg;
889 end = msg + msglen;
890
891 if (conn->certificate_requested) {
892 if (tls_write_client_certificate(conn, &pos, end) < 0) {
893 os_free(msg);
894 return NULL;
895 }
896 }
897
898 if (tls_write_client_key_exchange(conn, &pos, end) < 0 ||
899 (conn->certificate_requested && conn->cred && conn->cred->key &&
900 tls_write_client_certificate_verify(conn, &pos, end) < 0) ||
901 tls_write_client_change_cipher_spec(conn, &pos, end) < 0 ||
902 tls_write_client_finished(conn, &pos, end) < 0) {
903 os_free(msg);
904 return NULL;
905 }
906
907 *out_len = pos - msg;
908
909 conn->state = SERVER_CHANGE_CIPHER_SPEC;
910
911 return msg;
912 }
913
914
tls_send_change_cipher_spec(struct tlsv1_client * conn,size_t * out_len)915 static u8 * tls_send_change_cipher_spec(struct tlsv1_client *conn,
916 size_t *out_len)
917 {
918 u8 *msg, *end, *pos;
919
920 *out_len = 0;
921
922 msg = os_malloc(1000);
923 if (msg == NULL)
924 return NULL;
925
926 pos = msg;
927 end = msg + 1000;
928
929 if (tls_write_client_change_cipher_spec(conn, &pos, end) < 0 ||
930 tls_write_client_finished(conn, &pos, end) < 0) {
931 os_free(msg);
932 return NULL;
933 }
934
935 *out_len = pos - msg;
936
937 wpa_printf(MSG_DEBUG, "TLSv1: Session resumption completed "
938 "successfully");
939 if (!conn->session_resumed && conn->use_session_ticket)
940 conn->session_resumed = 1;
941 conn->state = ESTABLISHED;
942
943 return msg;
944 }
945
946
tlsv1_client_handshake_write(struct tlsv1_client * conn,size_t * out_len,int no_appl_data)947 u8 * tlsv1_client_handshake_write(struct tlsv1_client *conn, size_t *out_len,
948 int no_appl_data)
949 {
950 switch (conn->state) {
951 case CLIENT_KEY_EXCHANGE:
952 return tls_send_client_key_exchange(conn, out_len);
953 case CHANGE_CIPHER_SPEC:
954 return tls_send_change_cipher_spec(conn, out_len);
955 case ACK_FINISHED:
956 wpa_printf(MSG_DEBUG, "TLSv1: Handshake completed "
957 "successfully");
958 conn->state = ESTABLISHED;
959 *out_len = 0;
960 if (no_appl_data) {
961 /* Need to return something to get final TLS ACK. */
962 return os_malloc(1);
963 }
964 return NULL;
965 default:
966 wpa_printf(MSG_DEBUG, "TLSv1: Unexpected state %d while "
967 "generating reply", conn->state);
968 return NULL;
969 }
970 }
971
972
tlsv1_client_send_alert(struct tlsv1_client * conn,u8 level,u8 description,size_t * out_len)973 u8 * tlsv1_client_send_alert(struct tlsv1_client *conn, u8 level,
974 u8 description, size_t *out_len)
975 {
976 u8 *alert, *pos, *length;
977
978 wpa_printf(MSG_DEBUG, "TLSv1: Send Alert(%d:%d)", level, description);
979 *out_len = 0;
980
981 alert = os_malloc(10);
982 if (alert == NULL)
983 return NULL;
984
985 pos = alert;
986
987 /* TLSPlaintext */
988 /* ContentType type */
989 *pos++ = TLS_CONTENT_TYPE_ALERT;
990 /* ProtocolVersion version */
991 WPA_PUT_BE16(pos, conn->rl.tls_version ? conn->rl.tls_version :
992 TLS_VERSION);
993 pos += 2;
994 /* uint16 length (to be filled) */
995 length = pos;
996 pos += 2;
997 /* opaque fragment[TLSPlaintext.length] */
998
999 /* Alert */
1000 /* AlertLevel level */
1001 *pos++ = level;
1002 /* AlertDescription description */
1003 *pos++ = description;
1004
1005 WPA_PUT_BE16(length, pos - length - 2);
1006 *out_len = pos - alert;
1007
1008 return alert;
1009 }
1010