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