1 // Copyright 2015-2017 Espressif Systems (Shanghai) PTE LTD
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 
7 //     http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 #ifndef MDNS_PRIVATE_H_
15 #define MDNS_PRIVATE_H_
16 
17 #include "sdkconfig.h"
18 #include "mdns.h"
19 #include "esp_task.h"
20 #include "esp_timer.h"
21 
22 //#define MDNS_ENABLE_DEBUG
23 
24 #ifdef MDNS_ENABLE_DEBUG
25 #define _mdns_dbg_printf(...) printf(__VA_ARGS__)
26 #endif
27 
28 /** mDNS strict mode: Set this to 1 for the mDNS library to strictly follow the RFC6762:
29  * Strict features:
30  *   - to do not set original questions in response packets per RFC6762, sec 6
31  *
32  * The actual configuration is 0, i.e. non-strict mode, since some implementations,
33  * such as lwIP mdns resolver (used by standard POSIX API like getaddrinfo, gethostbyname)
34  * could not correctly resolve advertised names.
35  */
36 #ifndef CONFIG_MDNS_STRICT_MODE
37 #define MDNS_STRICT_MODE 0
38 #else
39 #define MDNS_STRICT_MODE 1
40 #endif
41 
42 #if !MDNS_STRICT_MODE
43 /* mDNS responders sometimes repeat queries in responses
44  * but according to RFC6762, sec 6: Responses MUST NOT contain
45  * any item in question field */
46 #define  MDNS_REPEAT_QUERY_IN_RESPONSE 1
47 #endif
48 /** The maximum number of services */
49 #define MDNS_MAX_SERVICES           CONFIG_MDNS_MAX_SERVICES
50 
51 #define MDNS_ANSWER_PTR_TTL         4500
52 #define MDNS_ANSWER_TXT_TTL         4500
53 #define MDNS_ANSWER_SRV_TTL         120
54 #define MDNS_ANSWER_A_TTL           120
55 #define MDNS_ANSWER_AAAA_TTL        120
56 
57 #define MDNS_FLAGS_AUTHORITATIVE    0x8400
58 #define MDNS_FLAGS_DISTRIBUTED      0x0200
59 
60 #define MDNS_NAME_REF               0xC000
61 
62 //custom type! only used by this implementation
63 //to help manage service discovery handling
64 #define MDNS_TYPE_SDPTR             0x0032
65 
66 #define MDNS_CLASS_IN               0x0001
67 #define MDNS_CLASS_ANY              0x00FF
68 #define MDNS_CLASS_IN_FLUSH_CACHE   0x8001
69 
70 #define MDNS_ANSWER_ALL             0x3F
71 #define MDNS_ANSWER_PTR             0x08
72 #define MDNS_ANSWER_TXT             0x04
73 #define MDNS_ANSWER_SRV             0x02
74 #define MDNS_ANSWER_A               0x01
75 #define MDNS_ANSWER_AAAA            0x10
76 #define MDNS_ANSWER_NSEC            0x20
77 #define MDNS_ANSWER_SDPTR           0x80
78 #define MDNS_ANSWER_AAAA_SIZE       16
79 
80 #define MDNS_SERVICE_PORT           5353                    // UDP port that the server runs on
81 #define MDNS_SERVICE_STACK_DEPTH    CONFIG_MDNS_TASK_STACK_SIZE
82 #define MDNS_TASK_PRIORITY          CONFIG_MDNS_TASK_PRIORITY
83 #if (MDNS_TASK_PRIORITY > ESP_TASK_PRIO_MAX)
84 #error "mDNS task priority is higher than ESP_TASK_PRIO_MAX"
85 #elif (MDNS_TASK_PRIORITY > ESP_TASKD_EVENT_PRIO)
86 #warning "mDNS task priority is higher than ESP_TASKD_EVENT_PRIO, mDNS library might not work correctly"
87 #endif
88 #define MDNS_TASK_AFFINITY          CONFIG_MDNS_TASK_AFFINITY
89 #define MDNS_SERVICE_ADD_TIMEOUT_MS CONFIG_MDNS_SERVICE_ADD_TIMEOUT_MS
90 
91 #define MDNS_PACKET_QUEUE_LEN       16                      // Maximum packets that can be queued for parsing
92 #define MDNS_ACTION_QUEUE_LEN       16                      // Maximum actions pending to the server
93 #define MDNS_TXT_MAX_LEN            1024                    // Maximum string length of text data in TXT record
94 #define MDNS_NAME_MAX_LEN           64                      // Maximum string length of hostname, instance, service and proto
95 #define MDNS_NAME_BUF_LEN           (MDNS_NAME_MAX_LEN+1)   // Maximum char buffer size to hold hostname, instance, service or proto
96 #define MDNS_MAX_PACKET_SIZE        1460                    // Maximum size of mDNS  outgoing packet
97 
98 #define MDNS_HEAD_LEN               12
99 #define MDNS_HEAD_ID_OFFSET         0
100 #define MDNS_HEAD_FLAGS_OFFSET      2
101 #define MDNS_HEAD_QUESTIONS_OFFSET  4
102 #define MDNS_HEAD_ANSWERS_OFFSET    6
103 #define MDNS_HEAD_SERVERS_OFFSET    8
104 #define MDNS_HEAD_ADDITIONAL_OFFSET 10
105 
106 #define MDNS_TYPE_OFFSET            0
107 #define MDNS_CLASS_OFFSET           2
108 #define MDNS_TTL_OFFSET             4
109 #define MDNS_LEN_OFFSET             8
110 #define MDNS_DATA_OFFSET            10
111 
112 #define MDNS_SRV_PRIORITY_OFFSET    0
113 #define MDNS_SRV_WEIGHT_OFFSET      2
114 #define MDNS_SRV_PORT_OFFSET        4
115 #define MDNS_SRV_FQDN_OFFSET        6
116 
117 #define MDNS_TIMER_PERIOD_US        (CONFIG_MDNS_TIMER_PERIOD_MS*1000)
118 
119 #define MDNS_SERVICE_LOCK()     xSemaphoreTake(_mdns_service_semaphore, portMAX_DELAY)
120 #define MDNS_SERVICE_UNLOCK()   xSemaphoreGive(_mdns_service_semaphore)
121 
122 #define queueToEnd(type, queue, item)       \
123     if (!queue) {                           \
124         queue = item;                       \
125     } else {                                \
126         type * _q = queue;                  \
127         while (_q->next) { _q = _q->next; } \
128         _q->next = item;                    \
129     }
130 
131 #define queueDetach(type, queue, item)              \
132     if (queue) {                                    \
133         if (queue == item) {                        \
134             queue = queue->next;                    \
135         } else {                                    \
136             type * _q = queue;                      \
137             while (_q->next && _q->next != item) {  \
138                 _q = _q->next;                      \
139             }                                       \
140             if (_q->next == item) {                 \
141                 _q->next = item->next;              \
142                 item->next = NULL;                  \
143             }                                       \
144         }                                           \
145     }
146 
147 #define queueFree(type, queue)  while (queue) { type * _q = queue; queue = queue->next; free(_q); }
148 
149 #define PCB_STATE_IS_PROBING(s) (s->state > PCB_OFF && s->state < PCB_ANNOUNCE_1)
150 #define PCB_STATE_IS_ANNOUNCING(s) (s->state > PCB_PROBE_3 && s->state < PCB_RUNNING)
151 #define PCB_STATE_IS_RUNNING(s) (s->state == PCB_RUNNING)
152 
153 #ifndef HOOK_MALLOC_FAILED
154 #define HOOK_MALLOC_FAILED  ESP_LOGE(TAG, "Cannot allocate memory (line: %d, free heap: %d bytes)", __LINE__, esp_get_free_heap_size());
155 #endif
156 
157 typedef enum {
158     PCB_OFF, PCB_DUP, PCB_INIT,
159     PCB_PROBE_1, PCB_PROBE_2, PCB_PROBE_3,
160     PCB_ANNOUNCE_1, PCB_ANNOUNCE_2, PCB_ANNOUNCE_3,
161     PCB_RUNNING
162 } mdns_pcb_state_t;
163 
164 typedef enum {
165     MDNS_ANSWER, MDNS_NS, MDNS_EXTRA
166 } mdns_parsed_record_type_t;
167 
168 typedef enum {
169     ACTION_SYSTEM_EVENT,
170     ACTION_HOSTNAME_SET,
171     ACTION_INSTANCE_SET,
172     ACTION_SERVICE_ADD,
173     ACTION_SERVICE_DEL,
174     ACTION_SERVICE_INSTANCE_SET,
175     ACTION_SERVICE_PORT_SET,
176     ACTION_SERVICE_TXT_REPLACE,
177     ACTION_SERVICE_TXT_SET,
178     ACTION_SERVICE_TXT_DEL,
179     ACTION_SERVICES_CLEAR,
180     ACTION_SEARCH_ADD,
181     ACTION_SEARCH_SEND,
182     ACTION_SEARCH_END,
183     ACTION_TX_HANDLE,
184     ACTION_RX_HANDLE,
185     ACTION_TASK_STOP,
186     ACTION_DELEGATE_HOSTNAME_ADD,
187     ACTION_DELEGATE_HOSTNAME_REMOVE,
188     ACTION_MAX
189 } mdns_action_type_t;
190 
191 
192 typedef struct {
193     uint16_t id;
194     union {
195         struct {
196             uint16_t qr :1;
197             uint16_t opCode :4;
198             uint16_t aa :1;
199             uint16_t tc :1;
200             uint16_t rd :1;
201             uint16_t ra :1;
202             uint16_t z :1;
203             uint16_t ad :1;
204             uint16_t cd :1;
205             uint16_t rCode :4;//response/error code
206         };
207         uint16_t value;
208     } flags;
209     uint16_t questions; //QDCOUNT
210     uint16_t answers;   //ANCOUNT
211     uint16_t servers;   //NSCOUNT
212     uint16_t additional;//ARCOUNT
213 } mdns_header_t;
214 
215 typedef struct {
216     char host[MDNS_NAME_BUF_LEN]; // hostname for A/AAAA records, instance name for SRV records
217     char service[MDNS_NAME_BUF_LEN];
218     char proto[MDNS_NAME_BUF_LEN];
219     char domain[MDNS_NAME_BUF_LEN];
220     uint8_t parts;
221     uint8_t sub;
222     bool    invalid;
223 } mdns_name_t;
224 
225 typedef struct mdns_parsed_question_s {
226     struct mdns_parsed_question_s * next;
227     uint16_t type;
228     bool unicast;
229     char * host;
230     char * service;
231     char * proto;
232     char * domain;
233 } mdns_parsed_question_t;
234 
235 typedef struct mdns_parsed_record_s {
236     struct mdns_parsed_record_s * next;
237     mdns_parsed_record_type_t record_type;
238     uint16_t type;
239     uint16_t clas;
240     uint8_t flush;
241     uint32_t ttl;
242     char * host;
243     char * service;
244     char * proto;
245     char * domain;
246     uint16_t data_len;
247     uint8_t *data;
248 } mdns_parsed_record_t;
249 
250 typedef struct {
251     mdns_if_t tcpip_if;
252     mdns_ip_protocol_t ip_protocol;
253     esp_ip_addr_t src;
254     uint16_t src_port;
255     uint8_t multicast;
256     uint8_t authoritative;
257     uint8_t probe;
258     uint8_t discovery;
259     uint8_t distributed;
260     mdns_parsed_question_t * questions;
261     mdns_parsed_record_t * records;
262     uint16_t id;
263 } mdns_parsed_packet_t;
264 
265 typedef struct {
266     mdns_if_t tcpip_if;
267     mdns_ip_protocol_t ip_protocol;
268     struct pbuf *pb;
269     esp_ip_addr_t src;
270     esp_ip_addr_t dest;
271     uint16_t src_port;
272     uint8_t multicast;
273 } mdns_rx_packet_t;
274 
275 typedef struct mdns_txt_linked_item_s {
276     const char * key;                       /*!< item key name */
277     char * value;                           /*!< item value string */
278     uint8_t value_len;                      /*!< item value length */
279     struct mdns_txt_linked_item_s * next;   /*!< next result, or NULL for the last result in the list */
280 } mdns_txt_linked_item_t;
281 
282 typedef struct {
283     const char * instance;
284     const char * service;
285     const char * proto;
286     const char * hostname;
287     uint16_t priority;
288     uint16_t weight;
289     uint16_t port;
290     mdns_txt_linked_item_t * txt;
291 } mdns_service_t;
292 
293 typedef struct mdns_srv_item_s {
294     struct mdns_srv_item_s * next;
295     mdns_service_t * service;
296 } mdns_srv_item_t;
297 
298 typedef struct mdns_out_question_s {
299     struct mdns_out_question_s * next;
300     uint16_t type;
301     bool unicast;
302     const char * host;
303     const char * service;
304     const char * proto;
305     const char * domain;
306     bool own_dynamic_memory;
307 } mdns_out_question_t;
308 
309 typedef struct mdns_host_item_t {
310     const char * hostname;
311     mdns_ip_addr_t *address_list;
312     struct mdns_host_item_t *next;
313 } mdns_host_item_t;
314 
315 typedef struct mdns_out_answer_s {
316     struct mdns_out_answer_s * next;
317     uint16_t type;
318     uint8_t bye;
319     uint8_t flush;
320     mdns_service_t * service;
321     mdns_host_item_t* host;
322     const char * custom_instance;
323     const char * custom_service;
324     const char * custom_proto;
325 } mdns_out_answer_t;
326 
327 typedef struct mdns_tx_packet_s {
328     struct mdns_tx_packet_s * next;
329     uint32_t send_at;
330     mdns_if_t tcpip_if;
331     mdns_ip_protocol_t ip_protocol;
332     esp_ip_addr_t dst;
333     uint16_t port;
334     uint16_t flags;
335     uint8_t distributed;
336     mdns_out_question_t * questions;
337     mdns_out_answer_t * answers;
338     mdns_out_answer_t * servers;
339     mdns_out_answer_t * additional;
340     bool queued;
341     uint16_t id;
342 } mdns_tx_packet_t;
343 
344 typedef struct {
345     mdns_pcb_state_t state;
346     struct udp_pcb * pcb;
347     mdns_srv_item_t ** probe_services;
348     uint8_t probe_services_len;
349     uint8_t probe_ip;
350     uint8_t probe_running;
351     uint16_t failed_probes;
352 } mdns_pcb_t;
353 
354 typedef enum {
355     SEARCH_OFF,
356     SEARCH_INIT,
357     SEARCH_RUNNING,
358     SEARCH_MAX
359 } mdns_search_once_state_t;
360 
361 typedef struct mdns_search_once_s {
362     struct mdns_search_once_s * next;
363 
364     mdns_search_once_state_t state;
365     uint32_t started_at;
366     uint32_t sent_at;
367     uint32_t timeout;
368     mdns_query_notify_t notifier;
369     SemaphoreHandle_t done_semaphore;
370     uint16_t type;
371     uint8_t max_results;
372     uint8_t num_results;
373     char * instance;
374     char * service;
375     char * proto;
376     mdns_result_t * result;
377 } mdns_search_once_t;
378 
379 typedef struct mdns_server_s {
380     struct {
381         mdns_pcb_t pcbs[MDNS_IP_PROTOCOL_MAX];
382     } interfaces[MDNS_IF_MAX];
383     const char * hostname;
384     const char * instance;
385     mdns_srv_item_t * services;
386     SemaphoreHandle_t lock;
387     QueueHandle_t action_queue;
388     mdns_tx_packet_t * tx_queue_head;
389     mdns_search_once_t * search_once;
390     esp_timer_handle_t timer_handle;
391 } mdns_server_t;
392 
393 typedef struct {
394     mdns_action_type_t type;
395     union {
396         struct {
397             char * hostname;
398             xTaskHandle calling_task;
399         } hostname_set;
400         char * instance;
401         struct {
402             esp_event_base_t event_base;
403             int32_t event_id;
404             esp_netif_t* interface;
405         } sys_event;
406         struct {
407             mdns_srv_item_t * service;
408         } srv_add;
409         struct {
410             mdns_srv_item_t * service;
411         } srv_del;
412         struct {
413             mdns_srv_item_t * service;
414             char * instance;
415         } srv_instance;
416         struct {
417             mdns_srv_item_t * service;
418             uint16_t port;
419         } srv_port;
420         struct {
421             mdns_srv_item_t * service;
422             mdns_txt_linked_item_t * txt;
423         } srv_txt_replace;
424         struct {
425             mdns_srv_item_t * service;
426             char * key;
427             char * value;
428             uint8_t value_len;
429         } srv_txt_set;
430         struct {
431             mdns_srv_item_t * service;
432             char * key;
433         } srv_txt_del;
434         struct {
435             mdns_search_once_t * search;
436         } search_add;
437         struct {
438             mdns_tx_packet_t * packet;
439         } tx_handle;
440         struct {
441             mdns_rx_packet_t * packet;
442         } rx_handle;
443         struct {
444             const char * hostname;
445             mdns_ip_addr_t *address_list;
446         } delegate_hostname;
447     } data;
448 } mdns_action_t;
449 
450 /*
451  * @brief  Convert mnds if to esp-netif handle
452  *
453  * @param  tcpip_if     mdns supported interface as internal enum
454  *
455  * @return
456  *     - ptr to esp-netif on success
457  *     - NULL if no available netif for current interface index
458  */
459 esp_netif_t *_mdns_get_esp_netif(mdns_if_t tcpip_if);
460 
461 
462 #endif /* MDNS_PRIVATE_H_ */
463