1 /*
2 * libwebsockets - small server side websockets and web server implementation
3 *
4 * Copyright (C) 2010 - 2021 Andy Green <andy@warmcat.com>
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to
8 * deal in the Software without restriction, including without limitation the
9 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10 * sell copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
22 * IN THE SOFTWARE.
23 *
24 * This provides a clean way to interface lws user code to be able to
25 * work unchanged on different systems for fetching common system information,
26 * and performing common system operations like reboot.
27 */
28
29/*
30 * Types of system blob that can be set and retreived
31 */
32
33typedef enum {
34	LWS_SYSBLOB_TYPE_AUTH,
35	LWS_SYSBLOB_TYPE_CLIENT_CERT_DER = LWS_SYSBLOB_TYPE_AUTH + 2,
36	LWS_SYSBLOB_TYPE_CLIENT_KEY_DER,
37	LWS_SYSBLOB_TYPE_DEVICE_SERIAL,
38	LWS_SYSBLOB_TYPE_DEVICE_FW_VERSION,
39	LWS_SYSBLOB_TYPE_DEVICE_TYPE,
40	LWS_SYSBLOB_TYPE_NTP_SERVER,
41	LWS_SYSBLOB_TYPE_MQTT_CLIENT_ID,
42	LWS_SYSBLOB_TYPE_MQTT_USERNAME,
43	LWS_SYSBLOB_TYPE_MQTT_PASSWORD,
44
45#if defined(LWS_WITH_SECURE_STREAMS_AUTH_SIGV4)
46	/* extend 4 more auth blobs, each has 2 slots */
47	LWS_SYSBLOB_TYPE_EXT_AUTH1,
48	LWS_SYSBLOB_TYPE_EXT_AUTH2 = LWS_SYSBLOB_TYPE_EXT_AUTH1 + 2,
49	LWS_SYSBLOB_TYPE_EXT_AUTH3 = LWS_SYSBLOB_TYPE_EXT_AUTH2 + 2,
50	LWS_SYSBLOB_TYPE_EXT_AUTH4 = LWS_SYSBLOB_TYPE_EXT_AUTH3 + 2,
51	LWS_SYSBLOB_TYPE_EXT_AUTH4_1,
52#endif
53
54	LWS_SYSBLOB_TYPE_COUNT /* ... always last */
55} lws_system_blob_item_t;
56
57/* opaque generic blob whose content may be on-the-heap or pointed-to
58 * directly case by case.  When it's on the heap, it can be produced by
59 * appending (it's a buflist underneath).  Either way, it can be consumed by
60 * copying out a given length from a given offset.
61 */
62
63typedef struct lws_system_blob lws_system_blob_t;
64
65LWS_EXTERN LWS_VISIBLE void
66lws_system_blob_direct_set(lws_system_blob_t *b, const uint8_t *ptr, size_t len);
67
68LWS_EXTERN LWS_VISIBLE void
69lws_system_blob_heap_empty(lws_system_blob_t *b);
70
71LWS_EXTERN LWS_VISIBLE int
72lws_system_blob_heap_append(lws_system_blob_t *b, const uint8_t *ptr, size_t len);
73
74LWS_EXTERN LWS_VISIBLE size_t
75lws_system_blob_get_size(lws_system_blob_t *b);
76
77/* return 0 and sets *ptr to point to blob data if possible, nonzero = fail */
78LWS_EXTERN LWS_VISIBLE int
79lws_system_blob_get_single_ptr(lws_system_blob_t *b, const uint8_t **ptr);
80
81LWS_EXTERN LWS_VISIBLE int
82lws_system_blob_get(lws_system_blob_t *b, uint8_t *ptr, size_t *len, size_t ofs);
83
84LWS_EXTERN LWS_VISIBLE void
85lws_system_blob_destroy(lws_system_blob_t *b);
86
87/*
88 * Get the opaque blob for index idx of various system blobs.  Returns 0 if
89 * *b was set otherwise nonzero means out of range
90 */
91
92LWS_EXTERN LWS_VISIBLE lws_system_blob_t *
93lws_system_get_blob(struct lws_context *context, lws_system_blob_item_t type,
94                    int idx);
95
96/*
97 * Lws view of system state... normal operation from user code perspective is
98 * dependent on implicit (eg, knowing the date for cert validation) and
99 * explicit dependencies.
100 *
101 * Bit of lws and user code can register notification handlers that can enforce
102 * dependent operations before state transitions can complete.
103 */
104
105typedef enum { /* keep system_state_names[] in sync in context.c */
106	LWS_SYSTATE_UNKNOWN,
107
108	LWS_SYSTATE_CONTEXT_CREATED,	 /* context was just created */
109	LWS_SYSTATE_INITIALIZED,	 /* protocols initialized.  Lws itself
110					  * can operate normally */
111	LWS_SYSTATE_IFACE_COLDPLUG,	 /* existing net ifaces iterated */
112	LWS_SYSTATE_DHCP,		 /* at least one net iface configured */
113	LWS_SYSTATE_CPD_PRE_TIME,	 /* Captive portal detect without valid
114					  * time, good for non-https tests... if
115					  * you care about it, implement and
116					  * call lws_system_ops_t
117					  * .captive_portal_detect_request()
118					  * and move the state forward according
119					  * to the result. */
120	LWS_SYSTATE_TIME_VALID,		 /* ntpclient ran, or hw time valid...
121					  * tls cannot work until we reach here
122					  */
123	LWS_SYSTATE_CPD_POST_TIME,	 /* Captive portal detect after time was
124					  * time, good for https tests... if
125					  * you care about it, implement and
126					  * call lws_system_ops_t
127					  * .captive_portal_detect_request()
128					  * and move the state forward according
129					  * to the result. */
130
131	LWS_SYSTATE_POLICY_VALID,	 /* user code knows how to operate... */
132	LWS_SYSTATE_REGISTERED,		 /* device has an identity... */
133	LWS_SYSTATE_AUTH1,		 /* identity used for main auth token */
134	LWS_SYSTATE_AUTH2,		 /* identity used for optional auth */
135
136	LWS_SYSTATE_OPERATIONAL,	 /* user code can operate normally */
137
138	LWS_SYSTATE_POLICY_INVALID,	 /* user code is changing its policies
139					  * drop everything done with old
140					  * policy, switch to new then enter
141					  * LWS_SYSTATE_POLICY_VALID */
142	LWS_SYSTATE_CONTEXT_DESTROYING,	 /* Context is being destroyed */
143} lws_system_states_t;
144
145/* Captive Portal Detect -related */
146
147typedef enum {
148	LWS_CPD_UNKNOWN = 0,	/* test didn't happen ince last DHCP acq yet */
149	LWS_CPD_INTERNET_OK,	/* no captive portal: our CPD test passed OK,
150				 * we can go out on the internet */
151	LWS_CPD_CAPTIVE_PORTAL,	/* we inferred we're behind a captive portal */
152	LWS_CPD_NO_INTERNET,	/* we couldn't touch anything */
153} lws_cpd_result_t;
154
155typedef void (*lws_attach_cb_t)(struct lws_context *context, int tsi, void *opaque);
156struct lws_attach_item;
157
158LWS_EXTERN LWS_VISIBLE int
159lws_tls_jit_trust_got_cert_cb(struct lws_context *cx, void *got_opaque,
160			      const uint8_t *skid, size_t skid_len,
161			      const uint8_t *der, size_t der_len);
162
163typedef struct lws_system_ops {
164	int (*reboot)(void);
165	int (*set_clock)(lws_usec_t us);
166	int (*attach)(struct lws_context *context, int tsi, lws_attach_cb_t cb,
167		      lws_system_states_t state, void *opaque,
168		      struct lws_attach_item **get);
169	/**< if \p get is NULL, add an attach callback request to the pt for
170	 * \p cb with arg \p opaque, that should be called when we're at or past
171	 * system state \p state.
172	 *
173	 * If \p get is non-NULL, look for the first listed item on the pt whose
174	 * state situation is ready, and set *get to point to it.  If no items,
175	 * or none where the system state is right, set *get to NULL.
176	 *
177	 * It's done like this so (*attach) can perform system-specific
178	 * locking outside of lws core, for both getting and adding items the
179	 * same so it is thread-safe.  A non-threadsafe helper
180	 * __lws_system_attach() is provided to do the actual work inside the
181	 * system-specific locking.
182	 */
183	int (*captive_portal_detect_request)(struct lws_context *context);
184	/**< Check if we can go out on the internet cleanly, or if we are being
185	 * redirected or intercepted by a captive portal.
186	 * Start the check that proceeds asynchronously, and report the results
187	 * by calling lws_captive_portal_detect_result() api
188	 */
189
190	int (*metric_report)(lws_metric_pub_t *mdata);
191	/**< metric \p item is reporting an event of kind \p rpt,
192	 * held in \p mdata... return 0 to leave the metric object as it is,
193	 * or nonzero to reset it. */
194
195	int (*jit_trust_query)(struct lws_context *cx, const uint8_t *skid,
196			       size_t skid_len, void *got_opaque);
197	/**< user defined trust store search, if we do trust a cert with SKID
198	 * matching skid / skid_len, then it should get hold of the DER for the
199	 * matching root CA and call
200	 * lws_tls_jit_trust_got_cert_cb(..., got_opaque) before cleaning up and
201	 * returning.  The DER should be destroyed if in heap before returning.
202	 */
203
204	uint32_t	wake_latency_us;
205	/**< time taken for this device to wake from suspend, in us
206	 */
207} lws_system_ops_t;
208
209#if defined(LWS_WITH_SYS_STATE)
210
211/**
212 * lws_system_get_state_manager() - return the state mgr object for system state
213 *
214 * \param context: the lws_context
215 *
216 * The returned pointer can be used with the lws_state_ apis
217 */
218
219LWS_EXTERN LWS_VISIBLE lws_state_manager_t *
220lws_system_get_state_manager(struct lws_context *context);
221
222#endif
223
224/* wrappers handle NULL members or no ops struct set at all cleanly */
225
226#define LWSSYSGAUTH_HEX (1 << 0)
227
228/**
229 * lws_system_get_ops() - get ahold of the system ops struct from the context
230 *
231 * \param context: the lws_context
232 *
233 * Returns the system ops struct.  It may return NULL and if not, anything in
234 * there may be NULL.
235 */
236LWS_EXTERN LWS_VISIBLE const lws_system_ops_t *
237lws_system_get_ops(struct lws_context *context);
238
239#if defined(LWS_WITH_SYS_STATE)
240
241/**
242 * lws_system_context_from_system_mgr() - return context from system state mgr
243 *
244 * \param mgr: pointer to specifically the system state mgr
245 *
246 * Returns the context from the system state mgr.  Helper since the lws_context
247 * is opaque.
248 */
249LWS_EXTERN LWS_VISIBLE struct lws_context *
250lws_system_context_from_system_mgr(lws_state_manager_t *mgr);
251
252#endif
253
254/**
255 * __lws_system_attach() - get and set items on context attach list
256 *
257 * \param context: context to get or set attach items to
258 * \param tsi: thread service index (normally 0)
259 * \param cb: callback to call from context event loop thread
260 * \param state: the lws_system state we have to be in or have passed through
261 * \param opaque: optional pointer to user specific info given to callback
262 * \param get: NULL, or pointer to pointer to take detached tail item on exit
263 *
264 * This allows other threads to enqueue callback requests to happen from a pt's
265 * event loop thread safely.  The callback gets the context pointer and a user
266 * opaque pointer that can be optionally given when the item is added to the
267 * attach list.
268 *
269 * This api is the no-locking core function for getting and setting items on the
270 * pt's attach list.  The lws_system operation (*attach) is the actual
271 * api that user and internal code calls for this feature, it should perform
272 * system-specific locking, call this helper, release the locking and then
273 * return the result.  This api is public only so it can be used in the locked
274 * implementation of (*attach).
275 *
276 * If get is NULL, then the call adds to the head of the pt attach list using
277 * cb, state, and opaque; if get is non-NULL, then *get is set to the first
278 * waiting attached item that meets the state criteria and that item is removed
279 * from the list.
280 *
281 * This is a non-threadsafe helper only designed to be called from
282 * implementations of struct lws_system's (*attach) operation where system-
283 * specific locking has been applied around it, making it threadsafe.
284 */
285LWS_EXTERN LWS_VISIBLE int
286__lws_system_attach(struct lws_context *context, int tsi, lws_attach_cb_t cb,
287		    lws_system_states_t state, void *opaque,
288		    struct lws_attach_item **get);
289
290
291enum {
292	LWSDH_IPV4_SUBNET_MASK		= 0,
293	LWSDH_IPV4_BROADCAST,
294	LWSDH_LEASE_SECS,
295	LWSDH_REBINDING_SECS,
296	LWSDH_RENEWAL_SECS,
297
298	_LWSDH_NUMS_COUNT,
299
300	LWSDH_SA46_IP			= 0,
301	LWSDH_SA46_DNS_SRV_1,
302	LWSDH_SA46_DNS_SRV_2,
303	LWSDH_SA46_DNS_SRV_3,
304	LWSDH_SA46_DNS_SRV_4,
305	LWSDH_SA46_IPV4_ROUTER,
306	LWSDH_SA46_NTP_SERVER,
307	LWSDH_SA46_DHCP_SERVER,
308
309	_LWSDH_SA46_COUNT,
310};
311
312typedef struct lws_dhcpc_ifstate {
313	char				ifname[16];
314	char				domain[64];
315	uint8_t				mac[6];
316	uint32_t			nums[_LWSDH_NUMS_COUNT];
317	lws_sockaddr46			sa46[_LWSDH_SA46_COUNT];
318} lws_dhcpc_ifstate_t;
319
320typedef int (*dhcpc_cb_t)(void *opaque, lws_dhcpc_ifstate_t *is);
321
322/**
323 * lws_dhcpc_request() - add a network interface to dhcpc management
324 *
325 * \param c: the lws_context
326 * \param i: the interface name, like "eth0"
327 * \param af: address family
328 * \param cb: the change callback
329 * \param opaque: opaque pointer given to the callback
330 *
331 * Register a network interface as being managed by DHCP.  lws will proceed to
332 * try to acquire an IP.  Requires LWS_WITH_SYS_DHCP_CLIENT at cmake.
333 */
334LWS_EXTERN LWS_VISIBLE int
335lws_dhcpc_request(struct lws_context *c, const char *i, int af, dhcpc_cb_t cb,
336		void *opaque);
337
338/**
339 * lws_dhcpc_remove() - remove a network interface to dhcpc management
340 *
341 * \param context: the lws_context
342 * \param iface: the interface name, like "eth0"
343 *
344 * Remove handling of the network interface from dhcp.
345 */
346LWS_EXTERN LWS_VISIBLE int
347lws_dhcpc_remove(struct lws_context *context, const char *iface);
348
349/**
350 * lws_dhcpc_status() - has any interface reached BOUND state
351 *
352 * \param context: the lws_context
353 * \param sa46: set to a DNS server from a bound interface, or NULL
354 *
355 * Returns 1 if any network interface managed by dhcpc has reached the BOUND
356 * state (has acquired an IP, gateway and DNS server), otherwise 0.
357 */
358LWS_EXTERN LWS_VISIBLE int
359lws_dhcpc_status(struct lws_context *context, lws_sockaddr46 *sa46);
360
361/**
362 * lws_system_cpd_start() - helper to initiate captive portal detection
363 *
364 * \param context: the lws_context
365 *
366 * Resets the context's captive portal state to LWS_CPD_UNKNOWN and calls the
367 * lws_system_ops_t captive_portal_detect_request() implementation to begin
368 * testing the captive portal state.
369 */
370LWS_EXTERN LWS_VISIBLE int
371lws_system_cpd_start(struct lws_context *context);
372
373LWS_EXTERN LWS_VISIBLE void
374lws_system_cpd_start_defer(struct lws_context *cx, lws_usec_t defer_us);
375
376
377/**
378 * lws_system_cpd_set() - report the result of the captive portal detection
379 *
380 * \param context: the lws_context
381 * \param result: one of the LWS_CPD_ constants representing captive portal state
382 *
383 * Sets the context's captive portal detection state to result.  User captive
384 * portal detection code would call this once it had a result from its test.
385 */
386LWS_EXTERN LWS_VISIBLE void
387lws_system_cpd_set(struct lws_context *context, lws_cpd_result_t result);
388
389
390/**
391 * lws_system_cpd_state_get() - returns the last tested captive portal state
392 *
393 * \param context: the lws_context
394 *
395 * Returns one of the LWS_CPD_ constants indicating the system's understanding
396 * of the current captive portal situation.
397 */
398LWS_EXTERN LWS_VISIBLE lws_cpd_result_t
399lws_system_cpd_state_get(struct lws_context *context);
400