xref: /freebsd/contrib/wpa/src/crypto/tls.h (revision 9a14aa017b21c292740c00ee098195cd46642730)
1 /*
2  * SSL/TLS interface definition
3  * Copyright (c) 2004-2010, Jouni Malinen <j@w1.fi>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  *
9  * Alternatively, this software may be distributed under the terms of BSD
10  * license.
11  *
12  * See README and COPYING for more details.
13  */
14 
15 #ifndef TLS_H
16 #define TLS_H
17 
18 struct tls_connection;
19 
20 struct tls_keys {
21 	const u8 *master_key; /* TLS master secret */
22 	size_t master_key_len;
23 	const u8 *client_random;
24 	size_t client_random_len;
25 	const u8 *server_random;
26 	size_t server_random_len;
27 	const u8 *inner_secret; /* TLS/IA inner secret */
28 	size_t inner_secret_len;
29 };
30 
31 enum tls_event {
32 	TLS_CERT_CHAIN_FAILURE,
33 	TLS_PEER_CERTIFICATE
34 };
35 
36 /*
37  * Note: These are used as identifier with external programs and as such, the
38  * values must not be changed.
39  */
40 enum tls_fail_reason {
41 	TLS_FAIL_UNSPECIFIED = 0,
42 	TLS_FAIL_UNTRUSTED = 1,
43 	TLS_FAIL_REVOKED = 2,
44 	TLS_FAIL_NOT_YET_VALID = 3,
45 	TLS_FAIL_EXPIRED = 4,
46 	TLS_FAIL_SUBJECT_MISMATCH = 5,
47 	TLS_FAIL_ALTSUBJECT_MISMATCH = 6,
48 	TLS_FAIL_BAD_CERTIFICATE = 7,
49 	TLS_FAIL_SERVER_CHAIN_PROBE = 8
50 };
51 
52 union tls_event_data {
53 	struct {
54 		int depth;
55 		const char *subject;
56 		enum tls_fail_reason reason;
57 		const char *reason_txt;
58 		const struct wpabuf *cert;
59 	} cert_fail;
60 
61 	struct {
62 		int depth;
63 		const char *subject;
64 		const struct wpabuf *cert;
65 		const u8 *hash;
66 		size_t hash_len;
67 	} peer_cert;
68 };
69 
70 struct tls_config {
71 	const char *opensc_engine_path;
72 	const char *pkcs11_engine_path;
73 	const char *pkcs11_module_path;
74 	int fips_mode;
75 
76 	void (*event_cb)(void *ctx, enum tls_event ev,
77 			 union tls_event_data *data);
78 	void *cb_ctx;
79 };
80 
81 #define TLS_CONN_ALLOW_SIGN_RSA_MD5 BIT(0)
82 #define TLS_CONN_DISABLE_TIME_CHECKS BIT(1)
83 
84 /**
85  * struct tls_connection_params - Parameters for TLS connection
86  * @ca_cert: File or reference name for CA X.509 certificate in PEM or DER
87  * format
88  * @ca_cert_blob: ca_cert as inlined data or %NULL if not used
89  * @ca_cert_blob_len: ca_cert_blob length
90  * @ca_path: Path to CA certificates (OpenSSL specific)
91  * @subject_match: String to match in the subject of the peer certificate or
92  * %NULL to allow all subjects
93  * @altsubject_match: String to match in the alternative subject of the peer
94  * certificate or %NULL to allow all alternative subjects
95  * @client_cert: File or reference name for client X.509 certificate in PEM or
96  * DER format
97  * @client_cert_blob: client_cert as inlined data or %NULL if not used
98  * @client_cert_blob_len: client_cert_blob length
99  * @private_key: File or reference name for client private key in PEM or DER
100  * format (traditional format (RSA PRIVATE KEY) or PKCS#8 (PRIVATE KEY)
101  * @private_key_blob: private_key as inlined data or %NULL if not used
102  * @private_key_blob_len: private_key_blob length
103  * @private_key_passwd: Passphrase for decrypted private key, %NULL if no
104  * passphrase is used.
105  * @dh_file: File name for DH/DSA data in PEM format, or %NULL if not used
106  * @dh_blob: dh_file as inlined data or %NULL if not used
107  * @dh_blob_len: dh_blob length
108  * @engine: 1 = use engine (e.g., a smartcard) for private key operations
109  * (this is OpenSSL specific for now)
110  * @engine_id: engine id string (this is OpenSSL specific for now)
111  * @ppin: pointer to the pin variable in the configuration
112  * (this is OpenSSL specific for now)
113  * @key_id: the private key's id when using engine (this is OpenSSL
114  * specific for now)
115  * @cert_id: the certificate's id when using engine
116  * @ca_cert_id: the CA certificate's id when using engine
117  * @tls_ia: Whether to enable TLS/IA (for EAP-TTLSv1)
118  * @flags: Parameter options (TLS_CONN_*)
119  *
120  * TLS connection parameters to be configured with tls_connection_set_params()
121  * and tls_global_set_params().
122  *
123  * Certificates and private key can be configured either as a reference name
124  * (file path or reference to certificate store) or by providing the same data
125  * as a pointer to the data in memory. Only one option will be used for each
126  * field.
127  */
128 struct tls_connection_params {
129 	const char *ca_cert;
130 	const u8 *ca_cert_blob;
131 	size_t ca_cert_blob_len;
132 	const char *ca_path;
133 	const char *subject_match;
134 	const char *altsubject_match;
135 	const char *client_cert;
136 	const u8 *client_cert_blob;
137 	size_t client_cert_blob_len;
138 	const char *private_key;
139 	const u8 *private_key_blob;
140 	size_t private_key_blob_len;
141 	const char *private_key_passwd;
142 	const char *dh_file;
143 	const u8 *dh_blob;
144 	size_t dh_blob_len;
145 	int tls_ia;
146 
147 	/* OpenSSL specific variables */
148 	int engine;
149 	const char *engine_id;
150 	const char *pin;
151 	const char *key_id;
152 	const char *cert_id;
153 	const char *ca_cert_id;
154 
155 	unsigned int flags;
156 };
157 
158 
159 /**
160  * tls_init - Initialize TLS library
161  * @conf: Configuration data for TLS library
162  * Returns: Context data to be used as tls_ctx in calls to other functions,
163  * or %NULL on failure.
164  *
165  * Called once during program startup and once for each RSN pre-authentication
166  * session. In other words, there can be two concurrent TLS contexts. If global
167  * library initialization is needed (i.e., one that is shared between both
168  * authentication types), the TLS library wrapper should maintain a reference
169  * counter and do global initialization only when moving from 0 to 1 reference.
170  */
171 void * tls_init(const struct tls_config *conf);
172 
173 /**
174  * tls_deinit - Deinitialize TLS library
175  * @tls_ctx: TLS context data from tls_init()
176  *
177  * Called once during program shutdown and once for each RSN pre-authentication
178  * session. If global library deinitialization is needed (i.e., one that is
179  * shared between both authentication types), the TLS library wrapper should
180  * maintain a reference counter and do global deinitialization only when moving
181  * from 1 to 0 references.
182  */
183 void tls_deinit(void *tls_ctx);
184 
185 /**
186  * tls_get_errors - Process pending errors
187  * @tls_ctx: TLS context data from tls_init()
188  * Returns: Number of found error, 0 if no errors detected.
189  *
190  * Process all pending TLS errors.
191  */
192 int tls_get_errors(void *tls_ctx);
193 
194 /**
195  * tls_connection_init - Initialize a new TLS connection
196  * @tls_ctx: TLS context data from tls_init()
197  * Returns: Connection context data, conn for other function calls
198  */
199 struct tls_connection * tls_connection_init(void *tls_ctx);
200 
201 /**
202  * tls_connection_deinit - Free TLS connection data
203  * @tls_ctx: TLS context data from tls_init()
204  * @conn: Connection context data from tls_connection_init()
205  *
206  * Release all resources allocated for TLS connection.
207  */
208 void tls_connection_deinit(void *tls_ctx, struct tls_connection *conn);
209 
210 /**
211  * tls_connection_established - Has the TLS connection been completed?
212  * @tls_ctx: TLS context data from tls_init()
213  * @conn: Connection context data from tls_connection_init()
214  * Returns: 1 if TLS connection has been completed, 0 if not.
215  */
216 int tls_connection_established(void *tls_ctx, struct tls_connection *conn);
217 
218 /**
219  * tls_connection_shutdown - Shutdown TLS connection
220  * @tls_ctx: TLS context data from tls_init()
221  * @conn: Connection context data from tls_connection_init()
222  * Returns: 0 on success, -1 on failure
223  *
224  * Shutdown current TLS connection without releasing all resources. New
225  * connection can be started by using the same conn without having to call
226  * tls_connection_init() or setting certificates etc. again. The new
227  * connection should try to use session resumption.
228  */
229 int tls_connection_shutdown(void *tls_ctx, struct tls_connection *conn);
230 
231 enum {
232 	TLS_SET_PARAMS_ENGINE_PRV_VERIFY_FAILED = -3,
233 	TLS_SET_PARAMS_ENGINE_PRV_INIT_FAILED = -2
234 };
235 
236 /**
237  * tls_connection_set_params - Set TLS connection parameters
238  * @tls_ctx: TLS context data from tls_init()
239  * @conn: Connection context data from tls_connection_init()
240  * @params: Connection parameters
241  * Returns: 0 on success, -1 on failure,
242  * TLS_SET_PARAMS_ENGINE_PRV_INIT_FAILED (-2) on possible PIN error causing
243  * PKCS#11 engine failure, or
244  * TLS_SET_PARAMS_ENGINE_PRV_VERIFY_FAILED (-3) on failure to verify the
245  * PKCS#11 engine private key.
246  */
247 int __must_check
248 tls_connection_set_params(void *tls_ctx, struct tls_connection *conn,
249 			  const struct tls_connection_params *params);
250 
251 /**
252  * tls_global_set_params - Set TLS parameters for all TLS connection
253  * @tls_ctx: TLS context data from tls_init()
254  * @params: Global TLS parameters
255  * Returns: 0 on success, -1 on failure,
256  * TLS_SET_PARAMS_ENGINE_PRV_INIT_FAILED (-2) on possible PIN error causing
257  * PKCS#11 engine failure, or
258  * TLS_SET_PARAMS_ENGINE_PRV_VERIFY_FAILED (-3) on failure to verify the
259  * PKCS#11 engine private key.
260  */
261 int __must_check tls_global_set_params(
262 	void *tls_ctx, const struct tls_connection_params *params);
263 
264 /**
265  * tls_global_set_verify - Set global certificate verification options
266  * @tls_ctx: TLS context data from tls_init()
267  * @check_crl: 0 = do not verify CRLs, 1 = verify CRL for the user certificate,
268  * 2 = verify CRL for all certificates
269  * Returns: 0 on success, -1 on failure
270  */
271 int __must_check tls_global_set_verify(void *tls_ctx, int check_crl);
272 
273 /**
274  * tls_connection_set_verify - Set certificate verification options
275  * @tls_ctx: TLS context data from tls_init()
276  * @conn: Connection context data from tls_connection_init()
277  * @verify_peer: 1 = verify peer certificate
278  * Returns: 0 on success, -1 on failure
279  */
280 int __must_check tls_connection_set_verify(void *tls_ctx,
281 					   struct tls_connection *conn,
282 					   int verify_peer);
283 
284 /**
285  * tls_connection_set_ia - Set TLS/IA parameters
286  * @tls_ctx: TLS context data from tls_init()
287  * @conn: Connection context data from tls_connection_init()
288  * @tls_ia: 1 = enable TLS/IA
289  * Returns: 0 on success, -1 on failure
290  *
291  * This function is used to configure TLS/IA in server mode where
292  * tls_connection_set_params() is not used.
293  */
294 int __must_check tls_connection_set_ia(void *tls_ctx,
295 				       struct tls_connection *conn,
296 				       int tls_ia);
297 
298 /**
299  * tls_connection_get_keys - Get master key and random data from TLS connection
300  * @tls_ctx: TLS context data from tls_init()
301  * @conn: Connection context data from tls_connection_init()
302  * @keys: Structure of key/random data (filled on success)
303  * Returns: 0 on success, -1 on failure
304  */
305 int __must_check tls_connection_get_keys(void *tls_ctx,
306 					 struct tls_connection *conn,
307 					 struct tls_keys *keys);
308 
309 /**
310  * tls_connection_prf - Use TLS-PRF to derive keying material
311  * @tls_ctx: TLS context data from tls_init()
312  * @conn: Connection context data from tls_connection_init()
313  * @label: Label (e.g., description of the key) for PRF
314  * @server_random_first: seed is 0 = client_random|server_random,
315  * 1 = server_random|client_random
316  * @out: Buffer for output data from TLS-PRF
317  * @out_len: Length of the output buffer
318  * Returns: 0 on success, -1 on failure
319  *
320  * This function is optional to implement if tls_connection_get_keys() provides
321  * access to master secret and server/client random values. If these values are
322  * not exported from the TLS library, tls_connection_prf() is required so that
323  * further keying material can be derived from the master secret. If not
324  * implemented, the function will still need to be defined, but it can just
325  * return -1. Example implementation of this function is in tls_prf() function
326  * when it is called with seed set to client_random|server_random (or
327  * server_random|client_random).
328  */
329 int __must_check  tls_connection_prf(void *tls_ctx,
330 				     struct tls_connection *conn,
331 				     const char *label,
332 				     int server_random_first,
333 				     u8 *out, size_t out_len);
334 
335 /**
336  * tls_connection_handshake - Process TLS handshake (client side)
337  * @tls_ctx: TLS context data from tls_init()
338  * @conn: Connection context data from tls_connection_init()
339  * @in_data: Input data from TLS server
340  * @appl_data: Pointer to application data pointer, or %NULL if dropped
341  * Returns: Output data, %NULL on failure
342  *
343  * The caller is responsible for freeing the returned output data. If the final
344  * handshake message includes application data, this is decrypted and
345  * appl_data (if not %NULL) is set to point this data. The caller is
346  * responsible for freeing appl_data.
347  *
348  * This function is used during TLS handshake. The first call is done with
349  * in_data == %NULL and the library is expected to return ClientHello packet.
350  * This packet is then send to the server and a response from server is given
351  * to TLS library by calling this function again with in_data pointing to the
352  * TLS message from the server.
353  *
354  * If the TLS handshake fails, this function may return %NULL. However, if the
355  * TLS library has a TLS alert to send out, that should be returned as the
356  * output data. In this case, tls_connection_get_failed() must return failure
357  * (> 0).
358  *
359  * tls_connection_established() should return 1 once the TLS handshake has been
360  * completed successfully.
361  */
362 struct wpabuf * tls_connection_handshake(void *tls_ctx,
363 					 struct tls_connection *conn,
364 					 const struct wpabuf *in_data,
365 					 struct wpabuf **appl_data);
366 
367 /**
368  * tls_connection_server_handshake - Process TLS handshake (server side)
369  * @tls_ctx: TLS context data from tls_init()
370  * @conn: Connection context data from tls_connection_init()
371  * @in_data: Input data from TLS peer
372  * @appl_data: Pointer to application data pointer, or %NULL if dropped
373  * Returns: Output data, %NULL on failure
374  *
375  * The caller is responsible for freeing the returned output data.
376  */
377 struct wpabuf * tls_connection_server_handshake(void *tls_ctx,
378 						struct tls_connection *conn,
379 						const struct wpabuf *in_data,
380 						struct wpabuf **appl_data);
381 
382 /**
383  * tls_connection_encrypt - Encrypt data into TLS tunnel
384  * @tls_ctx: TLS context data from tls_init()
385  * @conn: Connection context data from tls_connection_init()
386  * @in_data: Plaintext data to be encrypted
387  * Returns: Encrypted TLS data or %NULL on failure
388  *
389  * This function is used after TLS handshake has been completed successfully to
390  * send data in the encrypted tunnel. The caller is responsible for freeing the
391  * returned output data.
392  */
393 struct wpabuf * tls_connection_encrypt(void *tls_ctx,
394 				       struct tls_connection *conn,
395 				       const struct wpabuf *in_data);
396 
397 /**
398  * tls_connection_decrypt - Decrypt data from TLS tunnel
399  * @tls_ctx: TLS context data from tls_init()
400  * @conn: Connection context data from tls_connection_init()
401  * @in_data: Encrypted TLS data
402  * Returns: Decrypted TLS data or %NULL on failure
403  *
404  * This function is used after TLS handshake has been completed successfully to
405  * receive data from the encrypted tunnel. The caller is responsible for
406  * freeing the returned output data.
407  */
408 struct wpabuf * tls_connection_decrypt(void *tls_ctx,
409 				       struct tls_connection *conn,
410 				       const struct wpabuf *in_data);
411 
412 /**
413  * tls_connection_resumed - Was session resumption used
414  * @tls_ctx: TLS context data from tls_init()
415  * @conn: Connection context data from tls_connection_init()
416  * Returns: 1 if current session used session resumption, 0 if not
417  */
418 int tls_connection_resumed(void *tls_ctx, struct tls_connection *conn);
419 
420 enum {
421 	TLS_CIPHER_NONE,
422 	TLS_CIPHER_RC4_SHA /* 0x0005 */,
423 	TLS_CIPHER_AES128_SHA /* 0x002f */,
424 	TLS_CIPHER_RSA_DHE_AES128_SHA /* 0x0031 */,
425 	TLS_CIPHER_ANON_DH_AES128_SHA /* 0x0034 */
426 };
427 
428 /**
429  * tls_connection_set_cipher_list - Configure acceptable cipher suites
430  * @tls_ctx: TLS context data from tls_init()
431  * @conn: Connection context data from tls_connection_init()
432  * @ciphers: Zero (TLS_CIPHER_NONE) terminated list of allowed ciphers
433  * (TLS_CIPHER_*).
434  * Returns: 0 on success, -1 on failure
435  */
436 int __must_check tls_connection_set_cipher_list(void *tls_ctx,
437 						struct tls_connection *conn,
438 						u8 *ciphers);
439 
440 /**
441  * tls_get_cipher - Get current cipher name
442  * @tls_ctx: TLS context data from tls_init()
443  * @conn: Connection context data from tls_connection_init()
444  * @buf: Buffer for the cipher name
445  * @buflen: buf size
446  * Returns: 0 on success, -1 on failure
447  *
448  * Get the name of the currently used cipher.
449  */
450 int __must_check tls_get_cipher(void *tls_ctx, struct tls_connection *conn,
451 				char *buf, size_t buflen);
452 
453 /**
454  * tls_connection_enable_workaround - Enable TLS workaround options
455  * @tls_ctx: TLS context data from tls_init()
456  * @conn: Connection context data from tls_connection_init()
457  * Returns: 0 on success, -1 on failure
458  *
459  * This function is used to enable connection-specific workaround options for
460  * buffer SSL/TLS implementations.
461  */
462 int __must_check tls_connection_enable_workaround(void *tls_ctx,
463 						  struct tls_connection *conn);
464 
465 /**
466  * tls_connection_client_hello_ext - Set TLS extension for ClientHello
467  * @tls_ctx: TLS context data from tls_init()
468  * @conn: Connection context data from tls_connection_init()
469  * @ext_type: Extension type
470  * @data: Extension payload (%NULL to remove extension)
471  * @data_len: Extension payload length
472  * Returns: 0 on success, -1 on failure
473  */
474 int __must_check tls_connection_client_hello_ext(void *tls_ctx,
475 						 struct tls_connection *conn,
476 						 int ext_type, const u8 *data,
477 						 size_t data_len);
478 
479 /**
480  * tls_connection_get_failed - Get connection failure status
481  * @tls_ctx: TLS context data from tls_init()
482  * @conn: Connection context data from tls_connection_init()
483  *
484  * Returns >0 if connection has failed, 0 if not.
485  */
486 int tls_connection_get_failed(void *tls_ctx, struct tls_connection *conn);
487 
488 /**
489  * tls_connection_get_read_alerts - Get connection read alert status
490  * @tls_ctx: TLS context data from tls_init()
491  * @conn: Connection context data from tls_connection_init()
492  * Returns: Number of times a fatal read (remote end reported error) has
493  * happened during this connection.
494  */
495 int tls_connection_get_read_alerts(void *tls_ctx, struct tls_connection *conn);
496 
497 /**
498  * tls_connection_get_write_alerts - Get connection write alert status
499  * @tls_ctx: TLS context data from tls_init()
500  * @conn: Connection context data from tls_connection_init()
501  * Returns: Number of times a fatal write (locally detected error) has happened
502  * during this connection.
503  */
504 int tls_connection_get_write_alerts(void *tls_ctx,
505 				    struct tls_connection *conn);
506 
507 /**
508  * tls_connection_get_keyblock_size - Get TLS key_block size
509  * @tls_ctx: TLS context data from tls_init()
510  * @conn: Connection context data from tls_connection_init()
511  * Returns: Size of the key_block for the negotiated cipher suite or -1 on
512  * failure
513  */
514 int tls_connection_get_keyblock_size(void *tls_ctx,
515 				     struct tls_connection *conn);
516 
517 #define TLS_CAPABILITY_IA 0x0001 /* TLS Inner Application (TLS/IA) */
518 /**
519  * tls_capabilities - Get supported TLS capabilities
520  * @tls_ctx: TLS context data from tls_init()
521  * Returns: Bit field of supported TLS capabilities (TLS_CAPABILITY_*)
522  */
523 unsigned int tls_capabilities(void *tls_ctx);
524 
525 /**
526  * tls_connection_ia_send_phase_finished - Send a TLS/IA PhaseFinished message
527  * @tls_ctx: TLS context data from tls_init()
528  * @conn: Connection context data from tls_connection_init()
529  * @final: 1 = FinalPhaseFinished, 0 = IntermediatePhaseFinished
530  * Returns: Encrypted TLS/IA data, %NULL on failure
531  *
532  * This function is used to send the TLS/IA end phase message, e.g., when the
533  * EAP server completes EAP-TTLSv1.
534  */
535 struct wpabuf * tls_connection_ia_send_phase_finished(
536 	void *tls_ctx, struct tls_connection *conn, int final);
537 
538 /**
539  * tls_connection_ia_final_phase_finished - Has final phase been completed
540  * @tls_ctx: TLS context data from tls_init()
541  * @conn: Connection context data from tls_connection_init()
542  * Returns: 1 if valid FinalPhaseFinished has been received, 0 if not, or -1
543  * on failure
544  */
545 int __must_check tls_connection_ia_final_phase_finished(
546 	void *tls_ctx, struct tls_connection *conn);
547 
548 /**
549  * tls_connection_ia_permute_inner_secret - Permute TLS/IA inner secret
550  * @tls_ctx: TLS context data from tls_init()
551  * @conn: Connection context data from tls_connection_init()
552  * @key: Session key material (session_key vectors with 2-octet length), or
553  * %NULL if no session key was generating in the current phase
554  * @key_len: Length of session key material
555  * Returns: 0 on success, -1 on failure
556  */
557 int __must_check tls_connection_ia_permute_inner_secret(
558 	void *tls_ctx, struct tls_connection *conn,
559 	const u8 *key, size_t key_len);
560 
561 typedef int (*tls_session_ticket_cb)
562 (void *ctx, const u8 *ticket, size_t len, const u8 *client_random,
563  const u8 *server_random, u8 *master_secret);
564 
565 int __must_check  tls_connection_set_session_ticket_cb(
566 	void *tls_ctx, struct tls_connection *conn,
567 	tls_session_ticket_cb cb, void *ctx);
568 
569 #endif /* TLS_H */
570