NetAddress.cpp

/**********
This library is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the
Free Software Foundation; either version 3 of the License, or (at your
option) any later version. (See <http://www.gnu.org/copyleft/lesser.html>.)

This library is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for
more details.

You should have received a copy of the GNU Lesser General Public License
along with this library; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
**********/
// "mTunnel" multicast access service
// Copyright (c) 1996-2019 Live Networks, Inc.  All rights reserved.
// Network Addresses
// Implementation

#include "NetAddress.hh"
#include "GroupsockHelper.hh"

#include <stddef.h>
#include <stdio.h>
#if defined(__WIN32__) || defined(_WIN32)
#define USE_GETHOSTBYNAME 1 /*because at least some Windows don't have getaddrinfo()*/
#else
#ifndef INADDR_NONE
#define INADDR_NONE 0xFFFFFFFF
#endif
#endif

////////// NetAddress //////////

NetAddress::NetAddress(u_int8_t const* data, unsigned length) {
  assign(data, length);
}

NetAddress::NetAddress(unsigned length) {
  fData = new u_int8_t[length];
  if (fData == NULL) {
    fLength = 0;
    return;
  }

  for (unsigned i = 0; i < length; ++i)	fData[i] = 0;
  fLength = length;
}

NetAddress::NetAddress(NetAddress const& orig) {
  assign(orig.data(), orig.length());
}

NetAddress& NetAddress::operator=(NetAddress const& rightSide) {
  if (&rightSide != this) {
    clean();
    assign(rightSide.data(), rightSide.length());
  }
  return *this;
}

NetAddress::~NetAddress() {
  clean();
}

void NetAddress::assign(u_int8_t const* data, unsigned length) {
  fData = new u_int8_t[length];
  if (fData == NULL) {
    fLength = 0;
    return;
  }

  for (unsigned i = 0; i < length; ++i)	fData[i] = data[i];
  fLength = length;
}

void NetAddress::clean() {
  delete[] fData; fData = NULL;
  fLength = 0;
}


////////// NetAddressList //////////

NetAddressList::NetAddressList(char const* hostname)
  : fNumAddresses(0), fAddressArray(NULL) {
  // First, check whether "hostname" is an IP address string:
  netAddressBits addr = our_inet_addr((char*)hostname);
  if (addr != INADDR_NONE) {
    // Yes, it was an IP address string.  Return a 1-element list with this address:
    fNumAddresses = 1;
    fAddressArray = new NetAddress*[fNumAddresses];
    if (fAddressArray == NULL) return;

    fAddressArray[0] = new NetAddress((u_int8_t*)&addr, sizeof (netAddressBits));
    return;
  }
    
  // "hostname" is not an IP address string; try resolving it as a real host name instead:
#if defined(USE_GETHOSTBYNAME) || defined(VXWORKS)
  struct hostent* host;
#if defined(VXWORKS)
  char hostentBuf[512];

  host = (struct hostent*)resolvGetHostByName((char*)hostname, (char*)&hostentBuf, sizeof hostentBuf);
#else
  host = gethostbyname((char*)hostname);
#endif
  if (host == NULL || host->h_length != 4 || host->h_addr_list == NULL) return; // no luck

  u_int8_t const** const hAddrPtr = (u_int8_t const**)host->h_addr_list;
  // First, count the number of addresses:
  u_int8_t const** hAddrPtr1 = hAddrPtr;
  while (*hAddrPtr1 != NULL) {
    ++fNumAddresses;
    ++hAddrPtr1;
  }

  // Next, set up the list:
  fAddressArray = new NetAddress*[fNumAddresses];
  if (fAddressArray == NULL) return;

  for (unsigned i = 0; i < fNumAddresses; ++i) {
    fAddressArray[i] = new NetAddress(hAddrPtr[i], host->h_length);
  }
#else
  // Use "getaddrinfo()" (rather than the older, deprecated "gethostbyname()"):
  struct addrinfo addrinfoHints;
  memset(&addrinfoHints, 0, sizeof addrinfoHints);
  addrinfoHints.ai_family = AF_INET; // For now, we're interested in IPv4 addresses only
  struct addrinfo* addrinfoResultPtr = NULL;
  int result = getaddrinfo(hostname, NULL, &addrinfoHints, &addrinfoResultPtr);
  if (result != 0 || addrinfoResultPtr == NULL) return; // no luck

  // First, count the number of addresses:
  const struct addrinfo* p = addrinfoResultPtr;
  while (p != NULL) {
    if (p->ai_addrlen < 4) continue; // sanity check: skip over addresses that are too small
    ++fNumAddresses;
    p = p->ai_next;
  }

  // Next, set up the list:
  fAddressArray = new NetAddress*[fNumAddresses];
  if (fAddressArray == NULL) return;

  unsigned i = 0;
  p = addrinfoResultPtr;
  while (p != NULL) {
    if (p->ai_addrlen < 4) continue;
    fAddressArray[i++] = new NetAddress((u_int8_t const*)&(((struct sockaddr_in*)p->ai_addr)->sin_addr.s_addr), 4);
    p = p->ai_next;
  }

  // Finally, free the data that we had allocated by calling "getaddrinfo()":
  freeaddrinfo(addrinfoResultPtr);
#endif
}

NetAddressList::NetAddressList(NetAddressList const& orig) {
  assign(orig.numAddresses(), orig.fAddressArray);
}

NetAddressList& NetAddressList::operator=(NetAddressList const& rightSide) {
  if (&rightSide != this) {
    clean();
    assign(rightSide.numAddresses(), rightSide.fAddressArray);
  }
  return *this;
}

NetAddressList::~NetAddressList() {
  clean();
}

void NetAddressList::assign(unsigned numAddresses, NetAddress** addressArray) {
  fAddressArray = new NetAddress*[numAddresses];
  if (fAddressArray == NULL) {
    fNumAddresses = 0;
    return;
  }

  for (unsigned i = 0; i < numAddresses; ++i) {
    fAddressArray[i] = new NetAddress(*addressArray[i]);
  }
  fNumAddresses = numAddresses;
}

void NetAddressList::clean() {
  while (fNumAddresses-- > 0) {
    delete fAddressArray[fNumAddresses];
  }
  delete[] fAddressArray; fAddressArray = NULL;
}

NetAddress const* NetAddressList::firstAddress() const {
  if (fNumAddresses == 0) return NULL;

  return fAddressArray[0];
}

////////// NetAddressList::Iterator //////////
NetAddressList::Iterator::Iterator(NetAddressList const& addressList)
  : fAddressList(addressList), fNextIndex(0) {}

NetAddress const* NetAddressList::Iterator::nextAddress() {
  if (fNextIndex >= fAddressList.numAddresses()) return NULL; // no more
  return fAddressList.fAddressArray[fNextIndex++];
}


////////// Port //////////

Port::Port(portNumBits num /* in host byte order */) {
  fPortNum = htons(num);
}

UsageEnvironment& operator<<(UsageEnvironment& s, const Port& p) {
  return s << ntohs(p.num());
}


////////// AddressPortLookupTable //////////

AddressPortLookupTable::AddressPortLookupTable()
  : fTable(HashTable::create(3)) { // three-word keys are used
}

AddressPortLookupTable::~AddressPortLookupTable() {
  delete fTable;
}

void* AddressPortLookupTable::Add(netAddressBits address1,
				  netAddressBits address2,
				  Port port, void* value) {
  int key[3];
  key[0] = (int)address1;
  key[1] = (int)address2;
  key[2] = (int)port.num();
  return fTable->Add((char*)key, value);
}

void* AddressPortLookupTable::Lookup(netAddressBits address1,
				     netAddressBits address2,
				     Port port) {
  int key[3];
  key[0] = (int)address1;
  key[1] = (int)address2;
  key[2] = (int)port.num();
  return fTable->Lookup((char*)key);
}

Boolean AddressPortLookupTable::Remove(netAddressBits address1,
				       netAddressBits address2,
				       Port port) {
  int key[3];
  key[0] = (int)address1;
  key[1] = (int)address2;
  key[2] = (int)port.num();
  return fTable->Remove((char*)key);
}

AddressPortLookupTable::Iterator::Iterator(AddressPortLookupTable& table)
  : fIter(HashTable::Iterator::create(*(table.fTable))) {
}

AddressPortLookupTable::Iterator::~Iterator() {
  delete fIter;
}

void* AddressPortLookupTable::Iterator::next() {
  char const* key; // dummy
  return fIter->next(key);
}


////////// isMulticastAddress() implementation //////////

Boolean IsMulticastAddress(netAddressBits address) {
  // Note: We return False for addresses in the range 224.0.0.0
  // through 224.0.0.255, because these are non-routable
  // Note: IPv4-specific #####
  netAddressBits addressInNetworkOrder = htonl(address);
  return addressInNetworkOrder >  0xE00000FF &&
         addressInNetworkOrder <= 0xEFFFFFFF;
}


////////// AddressString implementation //////////

AddressString::AddressString(struct sockaddr_in const& addr) {
  init(addr.sin_addr.s_addr);
}

AddressString::AddressString(struct in_addr const& addr) {
  init(addr.s_addr);
}

AddressString::AddressString(netAddressBits addr) {
  init(addr);
}

void AddressString::init(netAddressBits addr) {
  fVal = new char[16]; // large enough for "abc.def.ghi.jkl"
  netAddressBits addrNBO = htonl(addr); // make sure we have a value in a known byte order: big endian
  sprintf(fVal, "%u.%u.%u.%u", (addrNBO>>24)&0xFF, (addrNBO>>16)&0xFF, (addrNBO>>8)&0xFF, addrNBO&0xFF);
}

AddressString::~AddressString() {
  delete[] fVal;
}