sockets.cxx

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/*
 * sockets.cxx
 *
 * Berkley sockets classes.
 *
 * Portable Windows Library
 *
 * Copyright (c) 1993-1998 Equivalence Pty. Ltd.
 *
 * The contents of this file are subject to the Mozilla Public License
 * Version 1.0 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 * the License for the specific language governing rights and limitations
 * under the License.
 *
 * The Original Code is Portable Windows Library.
 *
 * The Initial Developer of the Original Code is Equivalence Pty. Ltd.
 *
 * Portions are Copyright (C) 1993 Free Software Foundation, Inc.
 * All Rights Reserved.
 *
 * Contributor(s): ______________________________________.
 *
 * $Revision: 19426 $
 * $Author: rjongbloed $
 * $Date: 2008-02-09 03:19:51 +0000 (Sat, 09 Feb 2008) $
 */

#include <ptlib.h>

#include <ptlib/sockets.h>

#include <ctype.h>

#ifdef P_VXWORKS
// VxWorks variant of inet_ntoa() allocates INET_ADDR_LEN bytes via malloc
// BUT DOES NOT FREE IT !!!  Use inet_ntoa_b() instead.
#define INET_ADDR_LEN      18
extern "C" void inet_ntoa_b(struct in_addr inetAddress, char *pString);
#endif // P_VXWORKS

#ifdef __NUCLEUS_PLUS__
#include <ConfigurationClass.h>
#endif

#if P_HAS_QOS

#ifdef _WIN32
#include <winbase.h>
#include <winreg.h>

#ifndef _WIN32_WCE

void CALLBACK CompletionRoutine(DWORD dwError,
                                DWORD cbTransferred,
                                LPWSAOVERLAPPED lpOverlapped,
                                DWORD dwFlags);
                                

#endif  // _WIN32_WCE
#endif  // _WIN32
#endif // P_HAS_QOS

///////////////////////////////////////////////////////////////////////////////
// PIPSocket::Address

static int defaultIpAddressFamily = PF_INET;  // PF_UNSPEC;   // default to IPV4

static PIPSocket::Address loopback4(127,0,0,1);
static PIPSocket::Address broadcast4(INADDR_BROADCAST);
static PIPSocket::Address any4(INADDR_ANY);
static in_addr inaddr_empty;
#if P_HAS_IPV6
static PIPSocket::Address loopback6(16,(const BYTE *)"\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\001");
static PIPSocket::Address any6(16,(const BYTE *)"\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"); 
#endif


int PIPSocket::GetDefaultIpAddressFamily()
{
  return defaultIpAddressFamily;
}


void PIPSocket::SetDefaultIpAddressFamily(int ipAdressFamily)
{
  defaultIpAddressFamily = ipAdressFamily;
}


void PIPSocket::SetDefaultIpAddressFamilyV4()
{
  SetDefaultIpAddressFamily(PF_INET);
}


#if P_HAS_IPV6

void PIPSocket::SetDefaultIpAddressFamilyV6()
{
  SetDefaultIpAddressFamily(PF_INET6);
}


PBoolean PIPSocket::IsIpAddressFamilyV6Supported()
{
  int s = ::socket(PF_INET6, SOCK_DGRAM, 0);
  if (s < 0)
    return PFalse;

#if _WIN32
  closesocket(s);
#else
  _close(s);
#endif
  return PTrue;
}

#endif


PIPSocket::Address PIPSocket::GetDefaultIpAny()
{
#if P_HAS_IPV6
  if (defaultIpAddressFamily != PF_INET)
    return any6;
#endif

  return any4;
}


#if P_HAS_IPV6

class Psockaddr
{
  public:
    Psockaddr() { memset(&storage, 0, sizeof(storage)); }
    Psockaddr(const PIPSocket::Address & ip, WORD port);
    sockaddr* operator->() const { return (sockaddr *)&storage; }
    operator sockaddr*()   const { return (sockaddr *)&storage; }
    socklen_t GetSize() const;
    PIPSocket::Address GetIP() const;
    WORD GetPort() const;
  private:
    sockaddr_storage storage;
};


Psockaddr::Psockaddr(const PIPSocket::Address & ip, WORD port)
{
  memset(&storage, 0, sizeof(storage));

  if (ip.GetVersion() == 6) {
    sockaddr_in6 * addr6 = (sockaddr_in6 *)&storage;
    addr6->sin6_family = AF_INET6;
    addr6->sin6_addr = ip;
    addr6->sin6_port = htons(port);
    addr6->sin6_flowinfo = 0;
    addr6->sin6_scope_id = 0; // Should be set to the right interface....
  }
  else {
    sockaddr_in * addr4 = (sockaddr_in *)&storage;
    addr4->sin_family = AF_INET;
    addr4->sin_addr = ip;
    addr4->sin_port = htons(port);
  }
}


socklen_t Psockaddr::GetSize() const
{
  switch (((sockaddr *)&storage)->sa_family) {
    case AF_INET :
      return sizeof(sockaddr_in);
    case AF_INET6 :
      // RFC 2133 (Old IPv6 spec) size is 24
      // RFC 2553 (New IPv6 spec) size is 28
      return sizeof(sockaddr_in6);
    default :
      return sizeof(storage);
  }
}


PIPSocket::Address Psockaddr::GetIP() const
{
  switch (((sockaddr *)&storage)->sa_family) {
    case AF_INET :
      return ((sockaddr_in *)&storage)->sin_addr;
    case AF_INET6 :
      return ((sockaddr_in6 *)&storage)->sin6_addr;
    default :
      return 0;
  }
}


WORD Psockaddr::GetPort() const
{
  switch (((sockaddr *)&storage)->sa_family) {
    case AF_INET :
      return ntohs(((sockaddr_in *)&storage)->sin_port);
    case AF_INET6 :
      return ntohs(((sockaddr_in6 *)&storage)->sin6_port);
    default :
      return 0;
  }
}

#endif


#if (defined(_WIN32) || defined(WINDOWS)) && !defined(__NUCLEUS_MNT__)
static PWinSock dummyForWinSock; // Assure winsock is initialised
#endif

#if (defined(P_PTHREADS) && !defined(P_THREAD_SAFE_CLIB)) || defined(__NUCLEUS_PLUS__)
#define REENTRANT_BUFFER_LEN 1024
#endif


class PIPCacheData : public PObject
{
  PCLASSINFO(PIPCacheData, PObject)
  public:
    PIPCacheData(struct hostent * ent, const char * original);
#if P_HAS_IPV6
    PIPCacheData(struct addrinfo  * addr_info, const char * original);
    void AddEntry(struct addrinfo  * addr_info);
#endif
    const PString & GetHostName() const { return hostname; }
    const PIPSocket::Address & GetHostAddress() const { return address; }
    const PStringArray& GetHostAliases() const { return aliases; }
    PBoolean HasAged() const;
  private:
    PString            hostname;
    PIPSocket::Address address;
    PStringArray       aliases;
    PTime              birthDate;
};



PDICTIONARY(PHostByName_private, PCaselessString, PIPCacheData);

class PHostByName : PHostByName_private
{
  public:
    PBoolean GetHostName(const PString & name, PString & hostname);
    PBoolean GetHostAddress(const PString & name, PIPSocket::Address & address);
    PBoolean GetHostAliases(const PString & name, PStringArray & aliases);
  private:
    PIPCacheData * GetHost(const PString & name);
    PMutex mutex;
  friend void PIPSocket::ClearNameCache();
};

PMutex creationMutex;
static PHostByName & pHostByName()
{
  PWaitAndSignal m(creationMutex);
  static PHostByName t;
  return t;
}

class PIPCacheKey : public PObject
{
  PCLASSINFO(PIPCacheKey, PObject)
  public:
    PIPCacheKey(const PIPSocket::Address & a)
      { addr = a; }

    PObject * Clone() const
      { return new PIPCacheKey(*this); }

    PINDEX HashFunction() const
      { return (addr[1] + addr[2] + addr[3])%41; }

  private:
    PIPSocket::Address addr;
};

PDICTIONARY(PHostByAddr_private, PIPCacheKey, PIPCacheData);

class PHostByAddr : PHostByAddr_private
{
  public:
    PBoolean GetHostName(const PIPSocket::Address & addr, PString & hostname);
    PBoolean GetHostAddress(const PIPSocket::Address & addr, PIPSocket::Address & address);
    PBoolean GetHostAliases(const PIPSocket::Address & addr, PStringArray & aliases);
  private:
    PIPCacheData * GetHost(const PIPSocket::Address & addr);
    PMutex mutex;
  friend void PIPSocket::ClearNameCache();
};

static PHostByAddr & pHostByAddr()
{
  PWaitAndSignal m(creationMutex);
  static PHostByAddr t;
  return t;
}

#define new PNEW


//////////////////////////////////////////////////////////////////////////////
// IP Caching

PIPCacheData::PIPCacheData(struct hostent * host_info, const char * original)
{
  if (host_info == NULL) {
    address = 0;
    return;
  }

  hostname = host_info->h_name;
  if (host_info->h_addr != NULL)
#ifndef _WIN32_WCE
    address = *(DWORD *)host_info->h_addr;
#else
    address = PIPSocket::Address(host_info->h_length, (const BYTE *)host_info->h_addr);
#endif
  aliases.AppendString(host_info->h_name);

  PINDEX i;
  for (i = 0; host_info->h_aliases[i] != NULL; i++)
    aliases.AppendString(host_info->h_aliases[i]);

  for (i = 0; host_info->h_addr_list[i] != NULL; i++) {
#ifndef _WIN32_WCE
    PIPSocket::Address ip(*(DWORD *)host_info->h_addr_list[i]);
#else
    PIPSocket::Address ip(host_info->h_length, (const BYTE *)host_info->h_addr_list[i]);
#endif
    aliases.AppendString(ip.AsString());
  }

  for (i = 0; i < aliases.GetSize(); i++)
    if (aliases[i] *= original)
      return;

  aliases.AppendString(original);
}


#if P_HAS_IPV6

PIPCacheData::PIPCacheData(struct addrinfo * addr_info, const char * original)
{
  PINDEX i;
  if (addr_info == NULL) {
    address = 0;
    return;
  }

  // Fill Host primary informations
  hostname = addr_info->ai_canonname; // Fully Qualified Domain Name (FQDN)
  if (addr_info->ai_addr != NULL)
    address = PIPSocket::Address(addr_info->ai_family, addr_info->ai_addrlen, addr_info->ai_addr);

  // Next entries
  while (addr_info != NULL) {
    AddEntry(addr_info);
    addr_info = addr_info->ai_next;
  }

  // Add original as alias or allready added ?
  for (i = 0; i < aliases.GetSize(); i++) {
    if (aliases[i] *= original)
      return;
  }

  aliases.AppendString(original);
}


void PIPCacheData::AddEntry(struct addrinfo * addr_info)
{
  PINDEX i;

  if (addr_info == NULL)
    return;

  // Add canonical name
  PBoolean add_it = PTrue;
  for (i = 0; i < aliases.GetSize(); i++) {
    if (addr_info->ai_canonname != NULL && (aliases[i] *= addr_info->ai_canonname)) {
      add_it = PFalse;
      break;
    }
  }

  if (add_it && addr_info->ai_canonname != NULL)
    aliases.AppendString(addr_info->ai_canonname);

  // Add IP address
  PIPSocket::Address ip(addr_info->ai_family, addr_info->ai_addrlen, addr_info->ai_addr);
  add_it = PTrue;
  for (i = 0; i < aliases.GetSize(); i++) {
    if (aliases[i] *= ip.AsString()) {
      add_it = PFalse;
      break;
    }
  }

  if (add_it)
    aliases.AppendString(ip.AsString());
}

#endif


static PTimeInterval GetConfigTime(const char * /*key*/, DWORD dflt)
{
  //PConfig cfg("DNS Cache");
  //return cfg.GetInteger(key, dflt);
  return dflt;
}


PBoolean PIPCacheData::HasAged() const
{
  static PTimeInterval retirement = GetConfigTime("Age Limit", 300000); // 5 minutes
  PTime now;
  PTimeInterval age = now - birthDate;
  return age > retirement;
}


PBoolean PHostByName::GetHostName(const PString & name, PString & hostname)
{
  PIPCacheData * host = GetHost(name);

  if (host != NULL) {
    hostname = host->GetHostName();
    hostname.MakeUnique();
  }

  mutex.Signal();

  return host != NULL;
}


PBoolean PHostByName::GetHostAddress(const PString & name, PIPSocket::Address & address)
{
  PIPCacheData * host = GetHost(name);

  if (host != NULL)
    address = host->GetHostAddress();

  mutex.Signal();

  return host != NULL;
}


PBoolean PHostByName::GetHostAliases(const PString & name, PStringArray & aliases)
{
  PIPCacheData * host = GetHost(name);

  if (host != NULL)
    aliases = host->GetHostAliases();

  mutex.Signal();
  return host != NULL;
}


PIPCacheData * PHostByName::GetHost(const PString & name)
{
  mutex.Wait();

  PCaselessString key = name;

  // Check for a legal hostname as per RFC952
  if (key.IsEmpty() ||
      key.FindSpan("ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-.") != P_MAX_INDEX ||
      key[key.GetLength()-1] == '-' ||
      !isalpha(key[0]))
    return NULL;

  PIPCacheData * host = GetAt(key);
  int localErrNo = NETDB_SUCCESS;

  if (host != NULL && host->HasAged()) {
    SetAt(key, NULL);
    host = NULL;
  }

  if (host == NULL) {
    mutex.Signal();

#if P_HAS_IPV6
    struct addrinfo *res = NULL;
    struct addrinfo hints = { AI_CANONNAME, PF_UNSPEC };
    hints.ai_family = defaultIpAddressFamily;

    localErrNo = getaddrinfo((const char *)name, NULL , &hints, &res);
    mutex.Wait();

    if (localErrNo != NETDB_SUCCESS) {
      freeaddrinfo(res);
      return NULL;
    }
    host = new PIPCacheData(res, name);
    freeaddrinfo(res);
#else // P_HAS_IPV6

    int retry = 3;
    struct hostent * host_info;

#ifdef P_AIX

    struct hostent_data ht_data;
    memset(&ht_data, 0, sizeof(ht_data));
    struct hostent hostEnt;
    do {
      host_info = &hostEnt;
      ::gethostbyname_r(name,
                        host_info,
                        &ht_data);
      localErrNo = h_errno;
    } while (localErrNo == TRY_AGAIN && --retry > 0);

#elif defined(P_RTEMS) || defined(P_CYGWIN) || defined(P_MINGW)

    host_info = ::gethostbyname(name);
    localErrNo = h_errno;

#elif defined P_VXWORKS

    struct hostent hostEnt;
    host_info = Vx_gethostbyname((char *)name, &hostEnt);
    localErrNo = h_errno;