ESP8266 : Create a WiFi access point and provide a DNS and web server on it, catch all traffic
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| /* Create a WiFi access point and provide a web server on it. */ | |
| #include <ESP8266WiFi.h> | |
| #include "./DNSServer.h" // Patched lib | |
| #include <ESP8266WebServer.h> | |
| const byte DNS_PORT = 53; // Capture DNS requests on port 53 | |
| IPAddress apIP(10, 10, 10, 1); // Private network for server | |
| DNSServer dnsServer; // Create the DNS object | |
| ESP8266WebServer webServer(80); // HTTP server | |
| String responseHTML = "<!DOCTYPE html>" | |
| "<html lang=\"en\">" | |
| "<head>" | |
| "<meta charset=\"utf-8\">" | |
| "<meta name=\"viewport\" content=\"width=device-width, initial-scale=1\">" | |
| "<title>Internet of Bottles</title>" | |
| "</head>" | |
| "<body>" | |
| "<p>I'm just a stupid bottle with WiFi.</p>" | |
| "</body>" | |
| "</html>"; | |
| void setup() { | |
| // turn the LED on (HIGH is the voltage level) | |
| pinMode(LED_BUILTIN, OUTPUT); | |
| digitalWrite(LED_BUILTIN, HIGH); | |
| // configure access point | |
| WiFi.mode(WIFI_AP); | |
| WiFi.softAPConfig(apIP, apIP, IPAddress(255, 255, 255, 0)); | |
| WiFi.softAP("IoT --- Free WiFi"); // WiFi name | |
| // if DNSServer is started with "*" for domain name, it will reply with | |
| // provided IP to all DNS request | |
| dnsServer.start(DNS_PORT, "*", apIP); | |
| // replay to all requests with same HTML | |
| webServer.onNotFound([]() { | |
| webServer.send(200, "text/html", responseHTML); | |
| }); | |
| webServer.begin(); | |
| } | |
| void loop() { | |
| dnsServer.processNextRequest(); | |
| webServer.handleClient(); | |
| } | |
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| #include "./DNSServer.h" | |
| #include <lwip/def.h> | |
| #include <Arduino.h> | |
| #define DEBUG | |
| #define DEBUG_OUTPUT Serial | |
| DNSServer::DNSServer() | |
| { | |
| _ttl = htonl(60); | |
| _errorReplyCode = DNSReplyCode::NonExistentDomain; | |
| } | |
| bool DNSServer::start(const uint16_t &port, const String &domainName, | |
| const IPAddress &resolvedIP) | |
| { | |
| _port = port; | |
| _domainName = domainName; | |
| _resolvedIP[0] = resolvedIP[0]; | |
| _resolvedIP[1] = resolvedIP[1]; | |
| _resolvedIP[2] = resolvedIP[2]; | |
| _resolvedIP[3] = resolvedIP[3]; | |
| downcaseAndRemoveWwwPrefix(_domainName); | |
| return _udp.begin(_port) == 1; | |
| } | |
| void DNSServer::setErrorReplyCode(const DNSReplyCode &replyCode) | |
| { | |
| _errorReplyCode = replyCode; | |
| } | |
| void DNSServer::setTTL(const uint32_t &ttl) | |
| { | |
| _ttl = htonl(ttl); | |
| } | |
| void DNSServer::stop() | |
| { | |
| _udp.stop(); | |
| } | |
| void DNSServer::downcaseAndRemoveWwwPrefix(String &domainName) | |
| { | |
| domainName.toLowerCase(); | |
| domainName.replace("www.", ""); | |
| } | |
| void DNSServer::processNextRequest() | |
| { | |
| _currentPacketSize = _udp.parsePacket(); | |
| if (_currentPacketSize) | |
| { | |
| _buffer = (unsigned char*)malloc(_currentPacketSize * sizeof(char)); | |
| _udp.read(_buffer, _currentPacketSize); | |
| _dnsHeader = (DNSHeader*) _buffer; | |
| if (_dnsHeader->QR == DNS_QR_QUERY && | |
| _dnsHeader->OPCode == DNS_OPCODE_QUERY && | |
| requestIncludesOnlyOneQuestion() && | |
| (_domainName == "*" || getDomainNameWithoutWwwPrefix() == _domainName) | |
| ) | |
| { | |
| replyWithIP(); | |
| } | |
| else if (_dnsHeader->QR == DNS_QR_QUERY) | |
| { | |
| replyWithCustomCode(); | |
| } | |
| free(_buffer); | |
| } | |
| } | |
| bool DNSServer::requestIncludesOnlyOneQuestion() | |
| { | |
| return ntohs(_dnsHeader->QDCount) == 1 && | |
| _dnsHeader->ANCount == 0 && | |
| _dnsHeader->NSCount == 0 && | |
| _dnsHeader->ARCount == 0; | |
| } | |
| String DNSServer::getDomainNameWithoutWwwPrefix() | |
| { | |
| String parsedDomainName = ""; | |
| unsigned char *start = _buffer + 12; | |
| if (*start == 0) | |
| { | |
| return parsedDomainName; | |
| } | |
| int pos = 0; | |
| while(true) | |
| { | |
| unsigned char labelLength = *(start + pos); | |
| for(int i = 0; i < labelLength; i++) | |
| { | |
| pos++; | |
| parsedDomainName += (char)*(start + pos); | |
| } | |
| pos++; | |
| if (*(start + pos) == 0) | |
| { | |
| downcaseAndRemoveWwwPrefix(parsedDomainName); | |
| return parsedDomainName; | |
| } | |
| else | |
| { | |
| parsedDomainName += "."; | |
| } | |
| } | |
| } | |
| void DNSServer::replyWithIP() | |
| { | |
| _dnsHeader->QR = DNS_QR_RESPONSE; | |
| _dnsHeader->ANCount = _dnsHeader->QDCount; | |
| _dnsHeader->QDCount = _dnsHeader->QDCount; | |
| //_dnsHeader->RA = 1; | |
| _udp.beginPacket(_udp.remoteIP(), _udp.remotePort()); | |
| _udp.write(_buffer, _currentPacketSize); | |
| _udp.write((uint8_t)192); // answer name is a pointer | |
| _udp.write((uint8_t)12); // pointer to offset at 0x00c | |
| _udp.write((uint8_t)0); // 0x0001 answer is type A query (host address) | |
| _udp.write((uint8_t)1); | |
| _udp.write((uint8_t)0); //0x0001 answer is class IN (internet address) | |
| _udp.write((uint8_t)1); | |
| _udp.write((unsigned char*)&_ttl, 4); | |
| // Length of RData is 4 bytes (because, in this case, RData is IPv4) | |
| _udp.write((uint8_t)0); | |
| _udp.write((uint8_t)4); | |
| _udp.write(_resolvedIP, sizeof(_resolvedIP)); | |
| _udp.endPacket(); | |
| #ifdef DEBUG | |
| DEBUG_OUTPUT.print("DNS responds: "); | |
| DEBUG_OUTPUT.print(_resolvedIP[0]); | |
| DEBUG_OUTPUT.print("."); | |
| DEBUG_OUTPUT.print(_resolvedIP[1]); | |
| DEBUG_OUTPUT.print("."); | |
| DEBUG_OUTPUT.print(_resolvedIP[2]); | |
| DEBUG_OUTPUT.print("."); | |
| DEBUG_OUTPUT.print(_resolvedIP[3]); | |
| DEBUG_OUTPUT.print(" for "); | |
| DEBUG_OUTPUT.println(getDomainNameWithoutWwwPrefix()); | |
| #endif | |
| } | |
| void DNSServer::replyWithCustomCode() | |
| { | |
| _dnsHeader->QR = DNS_QR_RESPONSE; | |
| _dnsHeader->RCode = (unsigned char)_errorReplyCode; | |
| _dnsHeader->QDCount = 0; | |
| _udp.beginPacket(_udp.remoteIP(), _udp.remotePort()); | |
| _udp.write(_buffer, sizeof(DNSHeader)); | |
| _udp.endPacket(); | |
| } | |
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| #ifndef DNSServer_h | |
| #define DNSServer_h | |
| #include <WiFiUdp.h> | |
| #define DNS_QR_QUERY 0 | |
| #define DNS_QR_RESPONSE 1 | |
| #define DNS_OPCODE_QUERY 0 | |
| enum class DNSReplyCode | |
| { | |
| NoError = 0, | |
| FormError = 1, | |
| ServerFailure = 2, | |
| NonExistentDomain = 3, | |
| NotImplemented = 4, | |
| Refused = 5, | |
| YXDomain = 6, | |
| YXRRSet = 7, | |
| NXRRSet = 8 | |
| }; | |
| struct DNSHeader | |
| { | |
| uint16_t ID; // identification number | |
| unsigned char RD : 1; // recursion desired | |
| unsigned char TC : 1; // truncated message | |
| unsigned char AA : 1; // authoritive answer | |
| unsigned char OPCode : 4; // message_type | |
| unsigned char QR : 1; // query/response flag | |
| unsigned char RCode : 4; // response code | |
| unsigned char Z : 3; // its z! reserved | |
| unsigned char RA : 1; // recursion available | |
| uint16_t QDCount; // number of question entries | |
| uint16_t ANCount; // number of answer entries | |
| uint16_t NSCount; // number of authority entries | |
| uint16_t ARCount; // number of resource entries | |
| }; | |
| class DNSServer | |
| { | |
| public: | |
| DNSServer(); | |
| void processNextRequest(); | |
| void setErrorReplyCode(const DNSReplyCode &replyCode); | |
| void setTTL(const uint32_t &ttl); | |
| // Returns true if successful, false if there are no sockets available | |
| bool start(const uint16_t &port, | |
| const String &domainName, | |
| const IPAddress &resolvedIP); | |
| // stops the DNS server | |
| void stop(); | |
| private: | |
| WiFiUDP _udp; | |
| uint16_t _port; | |
| String _domainName; | |
| unsigned char _resolvedIP[4]; | |
| int _currentPacketSize; | |
| unsigned char* _buffer; | |
| DNSHeader* _dnsHeader; | |
| uint32_t _ttl; | |
| DNSReplyCode _errorReplyCode; | |
| void downcaseAndRemoveWwwPrefix(String &domainName); | |
| String getDomainNameWithoutWwwPrefix(); | |
| bool requestIncludesOnlyOneQuestion(); | |
| void replyWithIP(); | |
| void replyWithCustomCode(); | |
| }; | |
| #endif | |
What do I need to do to get a good readable url for the webserver? (like "http:\IoT.local")
What do I need to do to get a good readable url for the webserver? (like "http:\IoT.local")
Take a look at https://github.com/esp8266/Arduino/tree/master/libraries/ESP8266mDNS
Is it possible to provide a DNS in Station Mode?
Is it possible to provide a DNS in Station Mode?
Talvez seja melhor dares uma vista de olhos ao esp8266 RTOS SDK .
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Great! It's work for me. Thanks a lot!