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-rw-r--r--libraries/Ethernet/Dns.cpp423
1 files changed, 0 insertions, 423 deletions
diff --git a/libraries/Ethernet/Dns.cpp b/libraries/Ethernet/Dns.cpp
deleted file mode 100644
index b3c1a9d..0000000
--- a/libraries/Ethernet/Dns.cpp
+++ /dev/null
@@ -1,423 +0,0 @@
-// Arduino DNS client for WizNet5100-based Ethernet shield
-// (c) Copyright 2009-2010 MCQN Ltd.
-// Released under Apache License, version 2.0
-
-#include "w5100.h"
-#include "EthernetUdp.h"
-#include "util.h"
-
-#include "Dns.h"
-#include <string.h>
-//#include <stdlib.h>
-#include "Arduino.h"
-
-
-#define SOCKET_NONE 255
-// Various flags and header field values for a DNS message
-#define UDP_HEADER_SIZE 8
-#define DNS_HEADER_SIZE 12
-#define TTL_SIZE 4
-#define QUERY_FLAG (0)
-#define RESPONSE_FLAG (1<<15)
-#define QUERY_RESPONSE_MASK (1<<15)
-#define OPCODE_STANDARD_QUERY (0)
-#define OPCODE_INVERSE_QUERY (1<<11)
-#define OPCODE_STATUS_REQUEST (2<<11)
-#define OPCODE_MASK (15<<11)
-#define AUTHORITATIVE_FLAG (1<<10)
-#define TRUNCATION_FLAG (1<<9)
-#define RECURSION_DESIRED_FLAG (1<<8)
-#define RECURSION_AVAILABLE_FLAG (1<<7)
-#define RESP_NO_ERROR (0)
-#define RESP_FORMAT_ERROR (1)
-#define RESP_SERVER_FAILURE (2)
-#define RESP_NAME_ERROR (3)
-#define RESP_NOT_IMPLEMENTED (4)
-#define RESP_REFUSED (5)
-#define RESP_MASK (15)
-#define TYPE_A (0x0001)
-#define CLASS_IN (0x0001)
-#define LABEL_COMPRESSION_MASK (0xC0)
-// Port number that DNS servers listen on
-#define DNS_PORT 53
-
-// Possible return codes from ProcessResponse
-#define SUCCESS 1
-#define TIMED_OUT -1
-#define INVALID_SERVER -2
-#define TRUNCATED -3
-#define INVALID_RESPONSE -4
-
-void DNSClient::begin(const IPAddress& aDNSServer)
-{
- iDNSServer = aDNSServer;
- iRequestId = 0;
-}
-
-
-int DNSClient::inet_aton(const char* aIPAddrString, IPAddress& aResult)
-{
- // See if we've been given a valid IP address
- const char* p =aIPAddrString;
- while (*p &&
- ( (*p == '.') || (*p >= '0') || (*p <= '9') ))
- {
- p++;
- }
-
- if (*p == '\0')
- {
- // It's looking promising, we haven't found any invalid characters
- p = aIPAddrString;
- int segment =0;
- int segmentValue =0;
- while (*p && (segment < 4))
- {
- if (*p == '.')
- {
- // We've reached the end of a segment
- if (segmentValue > 255)
- {
- // You can't have IP address segments that don't fit in a byte
- return 0;
- }
- else
- {
- aResult[segment] = (byte)segmentValue;
- segment++;
- segmentValue = 0;
- }
- }
- else
- {
- // Next digit
- segmentValue = (segmentValue*10)+(*p - '0');
- }
- p++;
- }
- // We've reached the end of address, but there'll still be the last
- // segment to deal with
- if ((segmentValue > 255) || (segment > 3))
- {
- // You can't have IP address segments that don't fit in a byte,
- // or more than four segments
- return 0;
- }
- else
- {
- aResult[segment] = (byte)segmentValue;
- return 1;
- }
- }
- else
- {
- return 0;
- }
-}
-
-int DNSClient::getHostByName(const char* aHostname, IPAddress& aResult)
-{
- int ret =0;
-
- // See if it's a numeric IP address
- if (inet_aton(aHostname, aResult))
- {
- // It is, our work here is done
- return 1;
- }
-
- // Check we've got a valid DNS server to use
- if (iDNSServer == INADDR_NONE)
- {
- return INVALID_SERVER;
- }
-
- // Find a socket to use
- if (iUdp.begin(1024+(millis() & 0xF)) == 1)
- {
- // Try up to three times
- int retries = 0;
-// while ((retries < 3) && (ret <= 0))
- {
- // Send DNS request
- ret = iUdp.beginPacket(iDNSServer, DNS_PORT);
- if (ret != 0)
- {
- // Now output the request data
- ret = BuildRequest(aHostname);
- if (ret != 0)
- {
- // And finally send the request
- ret = iUdp.endPacket();
- if (ret != 0)
- {
- // Now wait for a response
- int wait_retries = 0;
- ret = TIMED_OUT;
- while ((wait_retries < 3) && (ret == TIMED_OUT))
- {
- ret = ProcessResponse(5000, aResult);
- wait_retries++;
- }
- }
- }
- }
- retries++;
- }
-
- // We're done with the socket now
- iUdp.stop();
- }
-
- return ret;
-}
-
-uint16_t DNSClient::BuildRequest(const char* aName)
-{
- // Build header
- // 1 1 1 1 1 1
- // 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
- // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- // | ID |
- // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- // |QR| Opcode |AA|TC|RD|RA| Z | RCODE |
- // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- // | QDCOUNT |
- // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- // | ANCOUNT |
- // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- // | NSCOUNT |
- // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- // | ARCOUNT |
- // +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- // As we only support one request at a time at present, we can simplify
- // some of this header
- iRequestId = millis(); // generate a random ID
- uint16_t twoByteBuffer;
-
- // FIXME We should also check that there's enough space available to write to, rather
- // FIXME than assume there's enough space (as the code does at present)
- iUdp.write((uint8_t*)&iRequestId, sizeof(iRequestId));
-
- twoByteBuffer = htons(QUERY_FLAG | OPCODE_STANDARD_QUERY | RECURSION_DESIRED_FLAG);
- iUdp.write((uint8_t*)&twoByteBuffer, sizeof(twoByteBuffer));
-
- twoByteBuffer = htons(1); // One question record
- iUdp.write((uint8_t*)&twoByteBuffer, sizeof(twoByteBuffer));
-
- twoByteBuffer = 0; // Zero answer records
- iUdp.write((uint8_t*)&twoByteBuffer, sizeof(twoByteBuffer));
-
- iUdp.write((uint8_t*)&twoByteBuffer, sizeof(twoByteBuffer));
- // and zero additional records
- iUdp.write((uint8_t*)&twoByteBuffer, sizeof(twoByteBuffer));
-
- // Build question
- const char* start =aName;
- const char* end =start;
- uint8_t len;
- // Run through the name being requested
- while (*end)
- {
- // Find out how long this section of the name is
- end = start;
- while (*end && (*end != '.') )
- {
- end++;
- }
-
- if (end-start > 0)
- {
- // Write out the size of this section
- len = end-start;
- iUdp.write(&len, sizeof(len));
- // And then write out the section
- iUdp.write((uint8_t*)start, end-start);
- }
- start = end+1;
- }
-
- // We've got to the end of the question name, so
- // terminate it with a zero-length section
- len = 0;
- iUdp.write(&len, sizeof(len));
- // Finally the type and class of question
- twoByteBuffer = htons(TYPE_A);
- iUdp.write((uint8_t*)&twoByteBuffer, sizeof(twoByteBuffer));
-
- twoByteBuffer = htons(CLASS_IN); // Internet class of question
- iUdp.write((uint8_t*)&twoByteBuffer, sizeof(twoByteBuffer));
- // Success! Everything buffered okay
- return 1;
-}
-
-
-uint16_t DNSClient::ProcessResponse(uint16_t aTimeout, IPAddress& aAddress)
-{
- uint32_t startTime = millis();
-
- // Wait for a response packet
- while(iUdp.parsePacket() <= 0)
- {
- if((millis() - startTime) > aTimeout)
- return TIMED_OUT;
- delay(50);
- }
-
- // We've had a reply!
- // Read the UDP header
- uint8_t header[DNS_HEADER_SIZE]; // Enough space to reuse for the DNS header
- // Check that it's a response from the right server and the right port
- if ( (iDNSServer != iUdp.remoteIP()) ||
- (iUdp.remotePort() != DNS_PORT) )
- {
- // It's not from who we expected
- return INVALID_SERVER;
- }
-
- // Read through the rest of the response
- if (iUdp.available() < DNS_HEADER_SIZE)
- {
- return TRUNCATED;
- }
- iUdp.read(header, DNS_HEADER_SIZE);
-
- uint16_t header_flags = htons(*((uint16_t*)&header[2]));
- // Check that it's a response to this request
- if ( ( iRequestId != (*((uint16_t*)&header[0])) ) ||
- ((header_flags & QUERY_RESPONSE_MASK) != (uint16_t)RESPONSE_FLAG) )
- {
- // Mark the entire packet as read
- iUdp.flush();
- return INVALID_RESPONSE;
- }
- // Check for any errors in the response (or in our request)
- // although we don't do anything to get round these
- if ( (header_flags & TRUNCATION_FLAG) || (header_flags & RESP_MASK) )
- {
- // Mark the entire packet as read
- iUdp.flush();
- return -5; //INVALID_RESPONSE;
- }
-
- // And make sure we've got (at least) one answer
- uint16_t answerCount = htons(*((uint16_t*)&header[6]));
- if (answerCount == 0 )
- {
- // Mark the entire packet as read
- iUdp.flush();
- return -6; //INVALID_RESPONSE;
- }
-
- // Skip over any questions
- for (uint16_t i =0; i < htons(*((uint16_t*)&header[4])); i++)
- {
- // Skip over the name
- uint8_t len;
- do
- {
- iUdp.read(&len, sizeof(len));
- if (len > 0)
- {
- // Don't need to actually read the data out for the string, just
- // advance ptr to beyond it
- while(len--)
- {
- iUdp.read(); // we don't care about the returned byte
- }
- }
- } while (len != 0);
-
- // Now jump over the type and class
- for (int i =0; i < 4; i++)
- {
- iUdp.read(); // we don't care about the returned byte
- }
- }
-
- // Now we're up to the bit we're interested in, the answer
- // There might be more than one answer (although we'll just use the first
- // type A answer) and some authority and additional resource records but
- // we're going to ignore all of them.
-
- for (uint16_t i =0; i < answerCount; i++)
- {
- // Skip the name
- uint8_t len;
- do
- {
- iUdp.read(&len, sizeof(len));
- if ((len & LABEL_COMPRESSION_MASK) == 0)
- {
- // It's just a normal label
- if (len > 0)
- {
- // And it's got a length
- // Don't need to actually read the data out for the string,
- // just advance ptr to beyond it
- while(len--)
- {
- iUdp.read(); // we don't care about the returned byte
- }
- }
- }
- else
- {
- // This is a pointer to a somewhere else in the message for the
- // rest of the name. We don't care about the name, and RFC1035
- // says that a name is either a sequence of labels ended with a
- // 0 length octet or a pointer or a sequence of labels ending in
- // a pointer. Either way, when we get here we're at the end of
- // the name
- // Skip over the pointer
- iUdp.read(); // we don't care about the returned byte
- // And set len so that we drop out of the name loop
- len = 0;
- }
- } while (len != 0);
-
- // Check the type and class
- uint16_t answerType;
- uint16_t answerClass;
- iUdp.read((uint8_t*)&answerType, sizeof(answerType));
- iUdp.read((uint8_t*)&answerClass, sizeof(answerClass));
-
- // Ignore the Time-To-Live as we don't do any caching
- for (int i =0; i < TTL_SIZE; i++)
- {
- iUdp.read(); // we don't care about the returned byte
- }
-
- // And read out the length of this answer
- // Don't need header_flags anymore, so we can reuse it here
- iUdp.read((uint8_t*)&header_flags, sizeof(header_flags));
-
- if ( (htons(answerType) == TYPE_A) && (htons(answerClass) == CLASS_IN) )
- {
- if (htons(header_flags) != 4)
- {
- // It's a weird size
- // Mark the entire packet as read
- iUdp.flush();
- return -9;//INVALID_RESPONSE;
- }
- iUdp.read(aAddress.raw_address(), 4);
- return SUCCESS;
- }
- else
- {
- // This isn't an answer type we're after, move onto the next one
- for (uint16_t i =0; i < htons(header_flags); i++)
- {
- iUdp.read(); // we don't care about the returned byte
- }
- }
- }
-
- // Mark the entire packet as read
- iUdp.flush();
-
- // If we get here then we haven't found an answer
- return -10;//INVALID_RESPONSE;
-}
-
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