source: abuse/trunk/src/net/tcpip.cpp @ 555 Tweet

/*
 *  Abuse - dark 2D side-scrolling platform game
 *  Copyright (c) 1995 Crack dot Com
 *  Copyright (c) 2005-2011 Sam Hocevar <sam@hocevar.net>
 *
 *  This software was released into the Public Domain. As with most public
 *  domain software, no warranty is made or implied by Crack dot Com, by
 *  Jonathan Clark, or by Sam Hocevar.
 */

#if defined HAVE_CONFIG_H
#   include "config.h"
#endif

#ifdef _AIX
#include <strings.h>
#endif
#include <ctype.h>

#if (defined(__APPLE__) && !defined(__MACH__))
#   include "GUSI.h"
#endif
#include "tcpip.h"

extern tcpip_protocol tcpip;

#define TCPIP_DEBUG

//{{{ net logging stuff

FILE *log_file=NULL;
extern int net_start();

static void net_log(char const *st, void *buf, long size)
{

  if (!log_file)
  {
    if (net_start())
      log_file=fopen("/tmp/abuseclient.log","wb");
    else
      log_file=fopen("/tmp/abuseserver.log","wb");
  }


    fprintf(log_file,"%s%ld - ",st,size);
    int i;
    for (i=0; i<size; i++)
      if (isprint(*((unsigned char *)buf+i)))
        fprintf(log_file,"%c",*((unsigned char *)buf+i));
      else fprintf(log_file,"~");

    fprintf(log_file," : ");

    for (i=0; i<size; i++)
    fprintf(log_file,"%02x, ",*((unsigned char *)buf+i));
    fprintf(log_file,"\n");
    fflush(log_file);

}
//}}}

////////////////////////////////////////////////////////////////////////
//
//  unix_fd methods
//

int unix_fd::read(void *buf, int size, net_address **addr)
//{{{
{
  int tr=::read(fd,(char*)buf,size);

  net_log("tcpip.cpp: unix_fd::read:", (char *) buf, (long) size);

  if (addr) *addr=NULL;
  return tr;
}
//}}}///////////////////////////////////

int unix_fd::write(void const *buf, int size, net_address *addr)
//{{{
{
  net_log("tcpip.cpp: unix_fd::write:", (char *) buf, (long) size);

  if (addr) fprintf(stderr,"Cannot change address for this socket type\n");
  return ::write(fd,(char*)buf,size);
}
//}}}///////////////////////////////////

void unix_fd::broadcastable()
//{{{
{
  int zz;
  if (setsockopt(fd,SOL_SOCKET,SO_BROADCAST,(char *)&zz,sizeof(zz))<0)
  {
    fprintf(stderr,"could not set socket option broadcast");
    return;
  }
}
//}}}///////////////////////////////////

////////////////////////////////////////////////////////////////////////
//
//  tcpip_protocol methods
//

net_address *tcpip_protocol::get_local_address()
//{{{
{
#if 0
     struct hostent *l_hn=gethostent();

    ip_address *a=new ip_address();
    memset(&a->addr,0,sizeof(a->addr));
    memcpy(&a->addr.sin_addr,*l_hn->h_addr_list,4);

    return a;
#else
  char my_name[100];                        // check to see if this address is 'hostname'
  gethostname(my_name,100);
  //ip_address *ret = 0;

  if (my_name[0]<'0' || my_name[0]>'9')
  {
      struct hostent *l_hn=gethostbyname(my_name);

      if (l_hn)
      {
          ip_address *a=new ip_address();
          memset(&a->addr,0,sizeof(a->addr));
          memcpy(&a->addr.sin_addr,*l_hn->h_addr_list,4);

          return a;
      }
      else
      {
          printf("Enter ip address:");
          fgets(my_name, sizeof( my_name ), stdin );
      }
    }

  char tmp[4];
  char const *np;
  sockaddr_in host;

  np = my_name;
  for (int i=0; i<4; i++)
  {
    int num = 0;
    while (*np)
    {
      if (*np=='.')
      {
        np++;
        break;
      }
      num = num*10 + *np - '0';
      np++;
    }
    tmp[i] = num;
  }

  memset( (char*) &host,0, sizeof(host));
  host.sin_family = AF_INET;
  host.sin_addr.s_addr = htonl(INADDR_ANY);
  memcpy(&host.sin_addr,tmp,sizeof(in_addr));

    return new ip_address(&host);
#endif
}
//}}}///////////////////////////////////

net_address *tcpip_protocol::get_node_address(char const *&server_name,
                                                                                            int def_port, int force_port)
//{{{
{
    sockaddr_in host;

    if (server_name[0]>='0' && server_name[0]<='9')
    {
        char tmp[4];
        char const *np;

      np = server_name;
      for (int i=0; i<4; i++)
      {
        int num = 0;
        while (*np && *np!=':')
        {
          if (*np=='.')
          {
            np++;
            break;
          }
          num = num*10 + *np - '0';
          np++;
        }
        tmp[i] = num;
        if (*np == ':' && !force_port)
        {
            int x;
          if (sscanf(np+1,"%d",&x)==1)
              def_port=x;
          }
      }

      memset( (char*) &host,0, sizeof(host));
      host.sin_family = AF_INET;
      host.sin_port = htons(def_port);
      host.sin_addr.s_addr = htonl(INADDR_ANY);
      memcpy(&host.sin_addr,tmp,sizeof(in_addr));

      return new ip_address(&host);
    }
    else
    {
      char name[256], *np;

      np=name;
      while (*server_name && *server_name!=':' && *server_name!='/')
        *(np++)=*(server_name)++;
      *np=0;
      if (*server_name==':')
      {
        server_name++;
        char port[256],*p;
        p=port;
        while (*server_name && *server_name!='/')
          *(p++)=*(server_name++);
        *p=0;
        int x;
        if (!force_port)
        {
          if (sscanf(port,"%d",&x)==1) def_port=x;
          else return 0;
        }
      }

      if (*server_name=='/') server_name++;

      hostent *hp=gethostbyname(name);
      if (!hp)
      {
        fprintf(stderr,"unable to locate server named '%s'\n",name);
        return 0;
      }

      memset( (char*) &host,0, sizeof(host));
      host.sin_family = AF_INET;
      host.sin_port = htons(def_port);
      host.sin_addr.s_addr = htonl(INADDR_ANY);
      memcpy(&host.sin_addr,hp->h_addr,hp->h_length);
    }
  return new ip_address(&host);
}
//}}}///////////////////////////////////

net_socket *tcpip_protocol::connect_to_server(net_address *addr, net_socket::socket_type sock_type)
//{{{
{
  if (addr->protocol_type()!=net_address::IP)
  {
    fprintf(stderr,"Procotol type not supported in the executable\n");
    return NULL;
  }

  int socket_fd=socket(AF_INET,sock_type==net_socket::SOCKET_SECURE ? SOCK_STREAM : SOCK_DGRAM,0);
  if (socket_fd<0)
  {
    fprintf(stderr,"unable to create socket (too many open files?)\n");
    return 0;
  }

#if (defined(__APPLE__) && !defined(__MACH__))
  int zz;
  if (setsockopt(socket_fd,SOL_SOCKET,SO_REUSEADDR,(char *)&zz,sizeof(zz))<0)
  {
    fprintf(stderr,"could not set socket option reuseaddr");
    return 0;
  }
#endif

  if (connect(socket_fd, (struct sockaddr *) &((ip_address *)addr)->addr, sizeof( ((ip_address *)addr)->addr ))==-1)
  {
    fprintf(stderr,"unable to connect\n");
    close(socket_fd);
    return 0;
  }

  if (sock_type==net_socket::SOCKET_SECURE)
    return new tcp_socket(socket_fd);
  else
    return new udp_socket(socket_fd);
}
//}}}///////////////////////////////////

net_socket *tcpip_protocol::create_listen_socket(int port, net_socket::socket_type sock_type)
//{{{
{
  int socket_fd=socket(AF_INET,sock_type==net_socket::SOCKET_SECURE ? SOCK_STREAM : SOCK_DGRAM,0);
  if (socket_fd<0)
  {
    fprintf(stderr,"unable to create socket (too many open files?)\n");
    return 0;
  }

#if (defined(__APPLE__) && !defined(__MACH__))
  int zz;
  if (setsockopt(socket_fd,SOL_SOCKET,SO_REUSEADDR,(char *)&zz,sizeof(zz))<0)
  {
    fprintf(stderr,"could not set socket option reuseaddr");
    return 0;
  }
#endif

  net_socket *s;
  if (sock_type==net_socket::SOCKET_SECURE)
    s=new tcp_socket(socket_fd);
  else s=new udp_socket(socket_fd);
  if (s->listen(port)==0)
  {
    delete s;
    return 0;
  }

  return s;
}
//}}}///////////////////////////////////

net_socket *tcpip_protocol::start_notify(int port, void *data, int len)
//{{{
{
    if (responder)
    {
        delete responder;
        delete bcast;
        responder = 0;
    }

    int resp_len = strlen(notify_response);
  notify_len = len + resp_len + 1;
  strcpy(notify_data,notify_response);
    notify_data[resp_len] = '.';
  memcpy(notify_data+resp_len+1,data,len);

  // create notifier socket
#ifdef TCPIP_DEBUG
    fprintf(stderr,"Creating notifier on port %d\n",port);
#endif
  notifier = create_listen_socket(port, net_socket::SOCKET_FAST);

  if (notifier)
  {
    notifier->read_selectable();
    notifier->write_unselectable();
  }
  else
        fprintf(stderr,"Couldn't start notifier\n");

  return notifier;
}
//}}}///////////////////////////////////

void tcpip_protocol::end_notify()
//{{{
{
  if (notifier)
    delete notifier;
  notifier = 0;

  notify_len = 0;
}
//}}}///////////////////////////////////

int tcpip_protocol::handle_notification()
//{{{
{
  if (!notifier)
    return 0;

  if (notifier->ready_to_read())
  {
    char buf[513];
    int len;
    // got a notification request "broadcast"
    ip_address *addr;
    net_address *tmp;

#ifdef TCPIP_DEBUG
        printf("Notifier: ");
#endif

    len = notifier->read(buf, 512, &tmp);
    addr = (ip_address *)tmp;
#ifdef TCPIP_DEBUG
        if (len>0) {
            buf[len] = 0;
            printf("[%s] ",buf);
        }
#endif
    if (addr && len>0)
    {
            buf[len] = 0;
      if  (strcmp(buf, notify_signature)==0) {
#ifdef TCPIP_DEBUG
                char s[256];
                addr->store_string(s,256);
                printf("responding to %s",s);
#endif
        // send notification data to requester
        notifier->write(notify_data,notify_len,addr);
            }

      delete addr;
    }
#ifdef TCPIP_DEBUG
        printf("\n");
#endif
    return 1;
  }
  if (notifier->error())
  {
    fprintf(stderr,"Error on notification socket!\n");
    return 1;
  }

  return 0;
}
//}}}///////////////////////////////////

net_address *tcpip_protocol::find_address(int port, char *name)
//{{{
{
  // name should be a 256 byte buffer
    char s[256];

    end_notify();

    if (!responder)
    {
//#ifdef TCPIP_DEBUG
        fprintf(stderr,"Creating responder on port %d\n",port);
//#endif
        responder = create_listen_socket(port, net_socket::SOCKET_FAST);
        if(responder)
        {
            responder->read_selectable();
            responder->write_unselectable();
            bcast = (ip_address *)get_local_address();
            bcast->set_port(port);

//#ifdef TCPIP_DEBUG
            *((unsigned char *)(&bcast->addr.sin_addr)+3) = 255;
            bcast->store_string(s,256);
            fprintf(stderr,"Simulating broadcast to [%s]\n",s);
//#endif

            *((unsigned char *)(&bcast->addr.sin_addr)+3) = 0;
        }
    }

  if (responder)
  {
    int i;

    for (i=0; i<5; i++)
    {
#ifdef TCPIP_DEBUG
            bcast->store_string(s,256);
            fprintf(stderr,"\r[%s]",s);
#endif
        int found = 0;

        for (p_request p = servers.begin(); !found && p!=servers.end(); ++p)
            if ( *((*p)->addr) == *bcast )
                found = 1;
        for (p_request q = returned.begin(); !found && q!=returned.end(); ++q)
            if ( *((*q)->addr) == *bcast )
                found = 1;

            if (!found) {
                responder->write((void*)notify_signature,
                                                 strlen(notify_signature),bcast);
                select(0);
            }
        *((unsigned char *)(&bcast->addr.sin_addr)+3) += 1;

        select(0);

        if (!servers.empty())
            break;
        }
  }

  if (servers.empty())
    return 0;

  servers.move_next(servers.begin_prev(), returned.begin_prev());
    ip_address *ret = (ip_address*)(*returned.begin())->addr->copy();
    strcpy(name,(*returned.begin())->name);

#ifdef TCPIP_DEBUG
    ret->store_string(s,256);
    fprintf(stderr,"Found [%s]\n",s);
#endif

  return ret;
}
//}}}///////////////////////////////////

void tcpip_protocol::reset_find_list()
//{{{
{
    p_request p;

    for (p=servers.begin(); p!=servers.end(); ++p)
        delete (*p)->addr;
    for (p=returned.begin(); p!=returned.end(); ++p)
        delete (*p)->addr;

  servers.erase_all();
  returned.erase_all();
}
//}}}///////////////////////////////////

int tcpip_protocol::handle_responder()
//{{{
{
  if (!responder)
    return 0;

  if (responder->ready_to_read())
  {
    char buf[513];
    int len;
    // got a notification response
    ip_address *addr;
    net_address *tmp;

#ifdef TCPIP_DEBUG
        fprintf(stderr,"Responder: ");
#endif

    len = responder->read(buf, 512, &tmp);
    addr = (ip_address *)tmp;

#ifdef TCPIP_DEBUG
        if (len>0) {
            buf[len] = 0;
            fprintf(stderr,"[%s] ",buf);
        }
#endif
    if (addr && len>0)
    {
        buf[len] = 0;
      buf[4] = 0;                                                // ack! hard coded numbers for now
      if (strcmp(buf,notify_response)==0)
      {
          int found=0;
          for (p_request p = servers.begin(); !found && p!=servers.end(); ++p)
              if ( *((*p)->addr) == *addr)
                   found = 1;
            for (p_request q = returned.begin(); !found && q!=returned.end(); ++q)
                if ( *((*q)->addr) == *addr )
                    found = 1;

          if (!found)
          {
#ifdef TCPIP_DEBUG
                    char s[256];
#endif
                    RequestItem *r = new RequestItem;
                    r->addr = addr;
                    strcpy(r->name,buf+5);                    // ack hard coded numbers for now
            servers.insert(r);
#ifdef TCPIP_DEBUG
                    addr->store_string(s,256);
                    fprintf(stderr,"accepted %s",s);
#endif
                }
            }
      else {
        delete addr;
            }
    }
#ifdef TCPIP_DEBUG
    fprintf(stderr,"\n");
#endif

    return 1;
  }
  if (responder->error())
  {
    fprintf(stderr,"Error on responder socket!\n");
    return 1;
  }

  return 0;
}
//}}}///////////////////////////////////

tcpip_protocol::tcpip_protocol()
//{{{
  : notifier(0), notify_len(0), responder(0)
{
#if (defined(__APPLE__) && !defined(__MACH__))
  GUSISetup(GUSIwithSIOUXSockets);
  GUSISetup(GUSIwithPPCSockets);
#endif
  FD_ZERO(&master_set);
  FD_ZERO(&master_write_set);
  FD_ZERO(&read_set);
  FD_ZERO(&exception_set);
  FD_ZERO(&write_set);
}
//}}}///////////////////////////////////

int tcpip_protocol::select(int block)
//{{{
{
  int ret;

  memcpy(&read_set,&master_set,sizeof(master_set));
  memcpy(&exception_set,&master_set,sizeof(master_set));
  memcpy(&write_set,&master_write_set,sizeof(master_set));
  if (block)
  {
    ret = 0;
    while (ret == 0) {
      // get number of sockets ready from system call
      ret = ::select(FD_SETSIZE,&read_set,&write_set,&exception_set,NULL);

      // remove notifier & responder events from the count of sockets selected
      if (handle_notification())
        ret--;
      if (handle_responder())
        ret--;
    }
  }
  else
  {
    timeval tv={ 0,0};
    // get number of sockets ready from system call
    ret = ::select(FD_SETSIZE,&read_set,&write_set,&exception_set,&tv);

    // remove notifier & responder events from the count of sockets selected
    if (handle_notification())
      ret--;
    if (handle_responder())
      ret--;
  }
  return ret;
}
//}}}///////////////////////////////////

void tcpip_protocol::cleanup()
//{{{
{
    if (notifier)
        end_notify();

    reset_find_list();

    if (responder) {
        delete responder;
        delete bcast;
        responder = 0;
    }
}
//}}}///////////////////////////////////

//{{{ Revision Log
/*//////////////////////////////////////////////////////////////////////
$Log$
//////////////////////////////////////////////////////////////////////
*/
//}}}

//{{{ Emacs Locals
// Local Variables:
// folded-file: t
// End:
//}}}