mdns: fix crash for hostname queries
Receiving TXT, PTR, SDPTR and SRV record type queries would crash the application if the hostname
was used as instance name.
Closes
@@ -445,6 +445,10 @@ static uint16_t _mdns_append_ptr_record(uint8_t * packet, uint16_t * index, cons
uint16_t record_length = 0;
uint8_t part_length;
+ if (service == NULL) {
+ return 0;
+ }
+
str[0] = instance;
str[1] = service;
str[2] = proto;
@@ -489,6 +493,10 @@ static uint16_t _mdns_append_sdptr_record(uint8_t * packet, uint16_t * index, md
uint16_t record_length = 0;
uint8_t part_length;
+ if (service == NULL) {
+ return 0;
+ }
+
sd_str[0] = (char*)"_services";
sd_str[1] = (char*)"_dns-sd";
sd_str[2] = (char*)"_udp";
@@ -534,6 +542,10 @@ static uint16_t _mdns_append_txt_record(uint8_t * packet, uint16_t * index, mdns
uint16_t record_length = 0;
uint8_t part_length;
+ if (service == NULL) {
+ return 0;
+ }
+
str[0] = _mdns_get_service_instance_name(service);
str[1] = service->service;
str[2] = service->proto;
@@ -602,6 +614,10 @@ static uint16_t _mdns_append_srv_record(uint8_t * packet, uint16_t * index, mdns
uint16_t record_length = 0;
uint8_t part_length;
+ if (service == NULL) {
+ return 0;
+ }
+
str[0] = _mdns_get_service_instance_name(service);
str[1] = service->service;
str[2] = service->proto;
@@ -1151,6 +1167,7 @@ static bool _mdns_alloc_answer(mdns_out_answer_t ** destnation, uint16_t type, m
}
a->type = type;
a->service = service;
+ a->custom_service = NULL;
a->bye = bye;
a->flush = flush;
a->next = NULL;
