Multicast in SoftAP mode (esp8266#96)

SDK 1.3 fixed a bug which caused multicast UDP to fail on SoftAP interface. Update MDNSResponder and documentation appropriately.

Author: igrr

hardware/esp8266com/esp8266/doc/reference.md

@@ -290,7 +290,6 @@ When listening to multicast packets, replace `udp.begin(port)` with
 `udp.beginMulticast(WiFi.localIP(), multicast_ip_addr, port)`.
 You can use `udp.destinationIP()` to tell whether the packet received was
 sent to the multicast or unicast address.
-Also note that multicast doesn't work on softAP interface.
 
 `WiFiServer`, `WiFiClient`, and `WiFiUDP` behave mostly the same way as with WiFi shield library.
 Four samples are provided for this library.
@@ -373,7 +372,6 @@ instead of the one that comes with this package.
 ## mDNS and DNS-SD responder (ESP8266mDNS library)
 
 Allows the sketch to respond to multicast DNS queries for domain names like "foo.local", and DNS-SD (service dicovery) queries.
-Currently the library only works on STA interface, AP interface is not supported.
 See attached example for details.
 
 ## SSDP responder (ESP8266SSDP)

hardware/esp8266com/esp8266/libraries/ESP8266mDNS/ESP8266mDNS.cpp

@@ -36,7 +36,7 @@ License (MIT license):
 
 #include "ESP8266mDNS.h"
 #include <functional>
-  
+
 #include "debug.h"
 
 extern "C" {
@@ -88,28 +88,28 @@ static const int MDNS_PORT = 5353;
 MDNSResponder::MDNSResponder() : _conn(0) { _services = 0; }
 MDNSResponder::~MDNSResponder() {}
 
-bool MDNSResponder::begin(const char* domain){ 
+bool MDNSResponder::begin(const char* domain){
   // Open the MDNS socket if it isn't already open.
-  
+
   size_t n = strlen(domain);
   if (n > 255) { // Can only handle domains that are 255 chars in length.
     return false;
   }
-  
+
   // Copy in domain characters as lowercase
   for (int i = 0; i < n; ++i)
     _hostName[i] = tolower(domain[i]);
   _hostName[n] = '\0';
-  
+
   os_strcpy(_boardName, ARDUINO_BOARD);
-  
+
   // Open the MDNS socket if it isn't already open.
   if (!_conn) {
     uint32_t ourIp = _getOurIp();
     if(ourIp == 0){
       return false;
     }
-    
+
     ip_addr_t ifaddr;
     ifaddr.addr = ourIp;
     ip_addr_t multicast_addr;
@@ -135,7 +135,7 @@ bool MDNSResponder::begin(const char* domain){
 
 void MDNSResponder::update() {
   if (!_conn->next()) {
-    return; 
+    return;
   }
   _parsePacket();
 }
@@ -163,15 +163,21 @@ uint16_t MDNSResponder::_getServicePort(char *name, char *proto){
 }
 
 uint32_t MDNSResponder::_getOurIp(){
-  if(wifi_get_opmode() & STATION_MODE){
+  int mode = wifi_get_opmode();
+  if(mode & STATION_MODE){
     struct ip_info staIpInfo;
     wifi_get_ip_info(STATION_IF, &staIpInfo);
     return staIpInfo.ip.addr;
-  }
+  } else if (mode & SOFTAP_MODE) {
+    struct ip_info staIpInfo;
+    wifi_get_ip_info(SOFTAP_IF, &staIpInfo);
+    return staIpInfo.ip.addr;
+  } else {
 #ifdef MDNS_DEBUG_ERR
     os_printf("ERR_NO_LOCAL_IP\n");
 #endif
-  return 0;
+    return 0;
+  }
 }
 
 void MDNSResponder::_parsePacket(){
@@ -180,52 +186,52 @@ void MDNSResponder::_parsePacket(){
   bool serviceParsed = false;
   bool protoParsed = false;
   bool localParsed = false;
-  
+
   char hostName[255];
   uint8_t hostNameLen;
-  
+
   char serviceName[32];
   uint8_t serviceNameLen;
   uint16_t servicePort;
-  
+
   char protoName[32];
   uint8_t protoNameLen;
-  
+
   uint16_t packetHeader[6];
-  
+
   for(i=0; i<6; i++) packetHeader[i] = _conn_read16();
 
   if((packetHeader[1] & 0x8000) != 0){ //not parsing responses yet
     _conn->flush();
     return;
   }
-  
+
   // PARSE REQUEST NAME
-  
+
   hostNameLen = _conn_read8();
   _conn_readS(hostName, hostNameLen);
   hostName[hostNameLen] = '\0';
-  
+
   if(hostName[0] == '_'){
     serviceParsed = true;
     memcpy(serviceName, hostName+1, hostNameLen);
     serviceNameLen = hostNameLen-1;
     hostNameLen = 0;
   }
-  
+
   if(hostNameLen > 0 && strcmp(_hostName, hostName) != 0){
 #ifdef MDNS_DEBUG_ERR
     os_printf("ERR_NO_HOST: %s\n", hostName);
 #endif
     _conn->flush();
     return;
   }
-  
+
   if(!serviceParsed){
     serviceNameLen = _conn_read8();
     _conn_readS(serviceName, serviceNameLen);
     serviceName[serviceNameLen] = '\0';
-    
+
     if(serviceName[0] == '_'){
       memcpy(serviceName, serviceName+1, serviceNameLen);
       serviceNameLen--;
@@ -253,7 +259,7 @@ void MDNSResponder::_parsePacket(){
       return;
     }
   }
-  
+
   if(!protoParsed){
     protoNameLen = _conn_read8();
     _conn_readS(protoName, protoNameLen);
@@ -270,7 +276,7 @@ void MDNSResponder::_parsePacket(){
       return;
     }
   }
-  
+
   if(!localParsed){
     char localName[32];
     uint8_t localNameLen = _conn_read8();
@@ -287,7 +293,7 @@ void MDNSResponder::_parsePacket(){
       return;
     }
   }
-  
+
   if(serviceNameLen > 0 && protoNameLen > 0){
     servicePort = _getServicePort(serviceName, protoName);
     if(servicePort == 0){
@@ -304,16 +310,16 @@ void MDNSResponder::_parsePacket(){
     _conn->flush();
     return;
   }
-  
+
   // RESPOND
-  
+
 #ifdef MDNS_DEBUG_RX
   os_printf("RX: REQ, ID:%u, Q:%u, A:%u, NS:%u, ADD:%u\n", packetHeader[0], packetHeader[2], packetHeader[3], packetHeader[4], packetHeader[5]);
 #endif
 
   uint16_t currentType;
   uint16_t currentClass;
-  
+
   int numQuestions = packetHeader[2];
   if(numQuestions > 4) numQuestions = 4;
   uint16_t questions[4];
@@ -326,21 +332,21 @@ void MDNSResponder::_parsePacket(){
     }
     currentClass = _conn_read16();
     if(currentClass & MDNS_CLASS_IN) questions[question++] = currentType;
-    
+
     if(numQuestions > 0){
       if(_conn_read16() != 0xC00C){//new question but for another host/service
         _conn->flush();
         numQuestions = 0;
       }
     }
-    
+
 #ifdef MDNS_DEBUG_RX
     os_printf("REQ: ");
     if(hostNameLen > 0) os_printf("%s.", hostName);
     if(serviceNameLen > 0) os_printf("_%s.", serviceName);
     if(protoNameLen > 0) os_printf("_%s.", protoName);
     os_printf("local. ");
-  
+
     if(currentType == MDNS_TYPE_AAAA) os_printf("  AAAA ");
     else if(currentType == MDNS_TYPE_A) os_printf("  A ");
     else if(currentType == MDNS_TYPE_PTR) os_printf("  PTR ");
@@ -351,7 +357,7 @@ void MDNSResponder::_parsePacket(){
     if(currentClass == MDNS_CLASS_IN) os_printf("  IN ");
     else if(currentClass == MDNS_CLASS_IN_FLUSH_CACHE) os_printf("  IN[F] ");
     else os_printf("  0x%04X ", currentClass);
-  
+
     os_printf("\n");
 #endif
   }
@@ -362,7 +368,7 @@ void MDNSResponder::_parsePacket(){
     else if(questions[i] == MDNS_TYPE_TXT) responseMask |= 0x4;
     else if(questions[i] == MDNS_TYPE_PTR) responseMask |= 0xF;
   }
-  
+
   return _reply(responseMask, (serviceName), (protoName), servicePort);
 }
 
@@ -371,14 +377,14 @@ void MDNSResponder::_parsePacket(){
 void MDNSResponder::_reply(uint8_t replyMask, char * service, char *proto, uint16_t port){
   int i;
   if(replyMask == 0) return;
-  
+
 #ifdef MDNS_DEBUG_TX
     os_printf("TX: mask:%01X, service:%s, proto:%s, port:%u\n", replyMask, service, proto, port);
 #endif
-  
+
   char nameLen = os_strlen(_hostName);
   size_t serviceLen = os_strlen(service);
-  
+
   uint8_t answerCount = 0;
   for(i=0;i<4;i++){
     if(replyMask & (1 << i)) answerCount++;
@@ -394,12 +400,12 @@ void MDNSResponder::_reply(uint8_t replyMask, char * service, char *proto, uint1
     0x00, 0x00, //Additional records
   };
   _conn->append(reinterpret_cast<const char*>(head), 12);
-  
+
   if((replyMask & 0x8) == 0){
     _conn->append(reinterpret_cast<const char*>(&nameLen), 1);
     _conn->append(reinterpret_cast<const char*>(_hostName), nameLen);
   }
-  
+
   if(replyMask & 0xE){
     uint8_t servHead[2] = {(uint8_t)(serviceLen+1), '_'};
     uint8_t protoHead[2] = {0x4, '_'};
@@ -408,14 +414,14 @@ void MDNSResponder::_reply(uint8_t replyMask, char * service, char *proto, uint1
     _conn->append(reinterpret_cast<const char*>(protoHead), 2);
     _conn->append(reinterpret_cast<const char*>(proto), 3);
   }
-  
+
   uint8_t local[7] = {
     0x05, //strlen(_local)
     0x6C, 0x6F, 0x63, 0x61, 0x6C, //local
     0x00, //End of domain
   };
   _conn->append(reinterpret_cast<const char*>(local), 7);
-  
+
   // PTR Response
   if(replyMask & 0x8){
     uint8_t ptr[10] = {
@@ -430,16 +436,16 @@ void MDNSResponder::_reply(uint8_t replyMask, char * service, char *proto, uint1
     uint8_t ptrTail[2] = {0xC0, 0x0C};
     _conn->append(reinterpret_cast<const char*>(ptrTail), 2);
   }
-  
+
   // TXT Response
   if(replyMask & 0x4){
     if(replyMask & 0x8){//send the name
       uint8_t txtHead[2] = {0xC0, (uint8_t)(36 + serviceLen)};
       _conn->append(reinterpret_cast<const char*>(txtHead), 2);
     }
-    
+
     uint8_t boardNameLen = os_strlen(_boardName);
-    
+
     uint8_t txt[24] = {
       0x00, 0x10, //Type TXT
       0x80, 0x01, //Class IN, with cache flush
@@ -450,9 +456,9 @@ void MDNSResponder::_reply(uint8_t replyMask, char * service, char *proto, uint1
     };
     _conn->append(reinterpret_cast<const char*>(txt), 17);
     _conn->append(reinterpret_cast<const char*>(_boardName), boardNameLen);
-    
+
   }
-  
+
   // SRV Response
   if(replyMask & 0x2){
     if(replyMask & 0xC){//send the name
@@ -461,7 +467,7 @@ void MDNSResponder::_reply(uint8_t replyMask, char * service, char *proto, uint1
         srvHead[1] = 36 + serviceLen;
       _conn->append(reinterpret_cast<const char*>(srvHead), 2);
     }
-    
+
     uint8_t srv[16] = {
       0x00, 0x21, //Type SRV
       0x80, 0x01, //Class IN, with cache flush
@@ -479,7 +485,7 @@ void MDNSResponder::_reply(uint8_t replyMask, char * service, char *proto, uint1
       srvTail[1] = 19 + serviceLen;
     _conn->append(reinterpret_cast<const char*>(srvTail), 2);
   }
-  
+
   // A Response
   if(replyMask & 0x1){
     uint32_t ip = _getOurIp();
@@ -488,7 +494,7 @@ void MDNSResponder::_reply(uint8_t replyMask, char * service, char *proto, uint1
       _conn->append(reinterpret_cast<const char*>(_hostName), nameLen);
       _conn->append(reinterpret_cast<const char*>(local), 7);
     }
-    
+
     uint8_t aaa[14] = {
       0x00, 0x01, //TYPE A
       0x80, 0x01, //Class IN, with cache flush

hardware/esp8266com/esp8266/libraries/ESP8266mDNS/ESP8266mDNS.h

@@ -13,10 +13,9 @@ implemented.
 
 Usage:
 - Include the ESP8266 Multicast DNS library in the sketch.
-- Create an instance of the MDNSResponder class.
 - Call the begin method in the sketch's setup and provide a domain name (without
-  the '.local' suffix, i.e. just provide 'foo' to resolve 'foo.local'), and the 
-  Adafruit CC3000 class instance.  Optionally provide a time to live (in seconds) 
+  the '.local' suffix, i.e. just provide 'foo' to resolve 'foo.local'), and the
+  Adafruit CC3000 class instance.  Optionally provide a time to live (in seconds)
   for the DNS record--the default is 1 hour.
 - Call the update method in each iteration of the sketch's loop function.
 
@@ -70,15 +69,15 @@ class MDNSResponder {
     return begin(hostName);
   }
   void update();
-  
+
   void addService(char *service, char *proto, uint16_t port);
   void addService(const char *service, const char *proto, uint16_t port){
     addService((char *)service, (char *)proto, port);
   }
   void addService(String service, String proto, uint16_t port){
     addService(service.c_str(), proto.c_str(), port);
   }
-  
+
 private:
   struct MDNSService * _services;
   UdpContext* _conn;