/*

  silcwin32net.c

  Author: Pekka Riikonen <priikone@silcnet.org>

  Copyright (C) 1997 - 2005 Pekka Riikonen

  The contents of this file are subject to one of the Licenses specified 
  in the COPYING file;  You may not use this file except in compliance 
  with the License.
  
  The software distributed under the License is distributed on an "AS IS"
  basis, in the hope that it will be useful, but WITHOUT WARRANTY OF ANY
  KIND, either expressed or implied.  See the COPYING file for more
  information.

*/
/* $Id: silcwin32net.c,v 1.15.4.1 2005/04/30 15:31:27 priikone Exp $ */

/* XXX IPv6 support missing */

#include "silcincludes.h"
#include "silcnet.h"

/* This function creates server or daemon or listener or what ever. This
   does not fork a new process, it must be done by the caller if caller
   wants to create a child process. This is used by the SILC server. 
   If argument `ip_addr' is NULL `any' address will be used. Returns 
   the created socket or -1 on error. */

int silc_net_create_server(int port, const char *ip_addr)
{
  SOCKET sock;
  int rval;
  struct sockaddr_in server;
  int len = sizeof(server.sin_addr);

  SILC_LOG_DEBUG(("Creating a new server listener"));

  /* Create the socket */
  sock = socket(PF_INET, SOCK_STREAM, 0);
  if (sock == INVALID_SOCKET) {
    SILC_LOG_ERROR(("Cannot create socket"));
    return -1;
  }

  /* Set the socket options */
  rval = silc_net_set_socket_opt(sock, SOL_SOCKET, SO_REUSEADDR, 1);
  if (rval != 0) {
    SILC_LOG_ERROR(("Cannot set socket options"));
    closesocket(sock);
    return -1;
  }

  /* Set the socket information for bind() */
  memset(&server, 0, sizeof(server));
  server.sin_family = AF_INET;
  if (port)
    server.sin_port = htons(port);

  /* Convert IP address to network byte order */
  if (ip_addr)
    silc_net_addr2bin(ip_addr, (unsigned char *)&server.sin_addr.s_addr, len);
  else
    server.sin_addr.s_addr = INADDR_ANY;

  /* Bind the server socket */
  rval = bind(sock, (struct sockaddr *)&server, sizeof(server));
  if (rval != 0) {
    SILC_LOG_ERROR(("Cannot bind socket"));
    closesocket(sock);
    return -1;
  }

  /* Specify that we are listenning */
  rval = listen(sock, 5);
  if (rval != 0) {
    SILC_LOG_ERROR(("Cannot set socket listenning"));
    closesocket(sock);
    return -1;
  }

  SILC_LOG_DEBUG(("Server listener created, fd=%d", sock));

  return sock;
}

/* Closes the server by closing the socket connection. */

void silc_net_close_server(int sock)
{
  shutdown(sock, 2);
  closesocket(sock);

  SILC_LOG_DEBUG(("Server socket closed"));
}

/* Creates a connection (TCP/IP) to a remote host. Returns the connection
   socket or -1 on error. This blocks the process while trying to create
   the connection. */

int silc_net_create_connection(const char *local_ip, int port, 
			       const char *host)
{
  SOCKET sock;
  int rval, err;
  struct hostent *dest;
  struct sockaddr_in desthost;

  SILC_LOG_DEBUG(("Creating connection to host %s port %d", host, port));

  /* Do host lookup */
  dest = gethostbyname(host);
  if (!dest) {
    SILC_LOG_ERROR(("Network (%s) unreachable: could not resolve the "
		    "IP address", host));
    return -1;
  }

  /* Set socket information */
  memset(&desthost, 0, sizeof(desthost));
  desthost.sin_port = htons(port);
  desthost.sin_family = AF_INET;
  memcpy(&desthost.sin_addr, dest->h_addr_list[0], sizeof(desthost.sin_addr));

  /* Create the connection socket */
  sock = socket(AF_INET, SOCK_STREAM, 0);
  if (sock == INVALID_SOCKET) {
    SILC_LOG_ERROR(("Cannot create socket"));
    return -1;
  }

  /* Connect to the host */
  rval = connect(sock, (struct sockaddr *)&desthost, sizeof(desthost));
  err = WSAGetLastError();
  if (rval == SOCKET_ERROR && err != WSAEWOULDBLOCK) {
    SILC_LOG_ERROR(("Cannot connect to remote host"));
    shutdown(sock, 2);
    closesocket(sock);
    return -1;
  }

  /* Set appropriate options */
#if defined(TCP_NODELAY)
  silc_net_set_socket_opt(sock, IPPROTO_TCP, TCP_NODELAY, 1);
#endif
  silc_net_set_socket_opt(sock, SOL_SOCKET, SO_KEEPALIVE, 1);

  SILC_LOG_DEBUG(("Connection created"));

  return sock;
}

/* Creates a connection (TCP/IP) to a remote host. Returns the connection
   socket or -1 on error. This creates non-blocking socket hence the
   connection returns directly. To get the result of the connect() one
   must select() the socket and read the result after it's ready. */

int silc_net_create_connection_async(const char *local_ip, int port, 
				     const char *host)
{
  SOCKET sock;
  int rval, err;
  struct hostent *dest;
  struct sockaddr_in desthost;

  SILC_LOG_DEBUG(("Creating connection (async) to host %s port %d", 
		  host, port));

  /* Do host lookup */
  dest = gethostbyname(host);
  if (!dest) {
    SILC_LOG_ERROR(("Network (%s) unreachable: could not resolve the "
		    "IP address", host));
    return -1;
  }

  /* Set socket information */
  memset(&desthost, 0, sizeof(desthost));
  desthost.sin_port = htons(port);
  desthost.sin_family = AF_INET;
  memcpy(&desthost.sin_addr, dest->h_addr_list[0], sizeof(desthost.sin_addr));

  /* Create the connection socket */
  sock = socket(AF_INET, SOCK_STREAM, 0);
  if (sock == INVALID_SOCKET) {
    SILC_LOG_ERROR(("Cannot create socket"));
    return -1;
  }

  /* Connect to the host */
  rval = connect(sock, (struct sockaddr *)&desthost, sizeof(desthost));
  err = WSAGetLastError();
  if (rval == SOCKET_ERROR && err != WSAEWOULDBLOCK) {
    SILC_LOG_ERROR(("Cannot connect to remote host"));
    shutdown(sock, 2);
    closesocket(sock);
    return -1;
  }

  /* Set socket to nonblocking mode */
  silc_net_set_socket_nonblock(sock);

  /* Set appropriate options */
#if defined(TCP_NODELAY)
  silc_net_set_socket_opt(sock, IPPROTO_TCP, TCP_NODELAY, 1);
#endif
  silc_net_set_socket_opt(sock, SOL_SOCKET, SO_KEEPALIVE, 1);

  SILC_LOG_DEBUG(("Connection created"));

  return sock;
}

/* Closes the connection by closing the socket connection. */

void silc_net_close_connection(int sock)
{
  closesocket(sock);
}

/* Converts the IP number string from numbers-and-dots notation to
   binary form. */

bool silc_net_addr2bin(const char *addr, void *bin, SilcUInt32 bin_len)
{
  unsigned long ret;

  ret = inet_addr(addr);

  if (bin_len < 4)
    return FALSE;

  memcpy(bin, (unsigned char *)&ret, 4);
  return ret != INADDR_NONE;
}

/* Set socket to non-blocking mode. */

int silc_net_set_socket_nonblock(int sock)
{
  unsigned long on = 1;
  return ioctlsocket(sock, FIONBIO, &on);
}

/* Init Winsock2. */

bool silc_net_win32_init(void)
{
  int ret, sopt = SO_SYNCHRONOUS_NONALERT;
  WSADATA wdata;
  WORD ver = MAKEWORD(1, 1);

  ret = WSAStartup(ver, &wdata);
  if (ret)
    return FALSE;

  /* Allow using the SOCKET's as file descriptors so that we can poll
     them with SILC Scheduler. */
  ret = setsockopt(INVALID_SOCKET, SOL_SOCKET, SO_OPENTYPE, (char *)&sopt,
		   sizeof(sopt));
  if (ret)
    return FALSE;

  return TRUE;
}

/* Uninit Winsock2 */

void silc_net_win32_uninit(void)
{
  WSACleanup();
}