//
// server.c - Simple TCP/UDP server using Winsock 2.2
//
// This is a part of the Microsoft Source Code Samples.
// Copyright 1996 - 2000 Microsoft Corporation.
// All rights reserved.
// This source code is only intended as a supplement to
// Microsoft Development Tools and/or WinHelp documentation.
// See these sources for detailed information regarding the
// Microsoft samples programs.
//
#define WIN32_LEAN_AND_MEAN
#include <winsock2.h>
#include <ws2tcpip.h>
#include <tpipv6.h> // For IPv6 Tech Preview.
#include <ip6.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
//
// It's too much trouble to include icmp6.h
//
typedef struct ICMPv6Header {
unsigned char Type;
unsigned char Code;
unsigned short Checksum;
} ICMPv6Header;
#define DEFAULT_PROTOCOL 254 // Arbitrary unassigned protocol
#define BUFFER_SIZE 65536
void Usage(char *ProgName) {
fprintf(stderr, "\nRaw socket receive program.\n");
fprintf(stderr, "\n%s [-p protocol] [-a address]\n\n",
ProgName);
fprintf(stderr, " protocol\t\tProtocol to receive messages for. (default %s)\n",
DEFAULT_PROTOCOL);
fprintf(stderr, " address\tIP address on which to bind. (default: unspecified address)\n");
WSACleanup();
exit(1);
}
LPSTR DecodeError(int ErrorCode)
{
static char Message[1024];
// If this program was multi-threaded, we'd want to use
// FORMAT_MESSAGE_ALLOCATE_BUFFER instead of a static buffer here.
// (And of course, free the buffer when we were done with it)
FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS |
FORMAT_MESSAGE_MAX_WIDTH_MASK, NULL, ErrorCode,
MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
(LPSTR)Message, 1024, NULL);
return Message;
}
int main(int argc, char **argv)
{
char Buffer[BUFFER_SIZE], Hostname[NI_MAXHOST];
unsigned char Protocol = DEFAULT_PROTOCOL;
char *Address = NULL;
int i, NumSocks, RetVal, FromLen, AmountRead;
SOCKADDR_STORAGE From;
WSADATA wsaData;
ADDRINFO Hints, *AddrInfo, *AI;
SOCKET ServSock[FD_SETSIZE];
fd_set SockSet;
// Parse arguments
if (argc > 1) {
for(i = 1;i < argc; i++) {
if ((argv[i][0] == '-') || (argv[i][0] == '/') &&
(argv[i][1] != 0) && (argv[i][2] == 0)) {
switch(tolower(argv[i][1])) {
case 'a':
if (argv[i+1]) {
if (argv[i+1][0] != '-') {
Address = argv[++i];
break;
}
}
Usage(argv[0]);
break;
case 'p':
if (argv[i+1]) {
if (argv[i+1][0] != '-') {
Protocol = atoi(argv[++i]);
break;
}
}
Usage(argv[0]);
break;
default:
Usage(argv[0]);
break;
}
} else
Usage(argv[0]);
}
}
// Ask for Winsock version 2.2.
if ((RetVal = WSAStartup(MAKEWORD(2, 2), &wsaData)) != 0) {
fprintf(stderr, "WSAStartup failed with error %d: %s\n",
RetVal, DecodeError(RetVal));
WSACleanup();
return -1;
}
//
// By setting the AI_PASSIVE flag in the hints to getaddrinfo, we're
// indicating that we intend to use the resulting address(es) to bind
// to a socket(s) for accepting incoming connections. This means that
// when the Address parameter is NULL, getaddrinfo will return one
// entry per allowed protocol family containing the unspecified address
// for that family.
//
memset(&Hints, 0, sizeof(Hints));
Hints.ai_family = PF_INET6;
Hints.ai_socktype = SOCK_DGRAM; // Lie until getaddrinfo is fixed.
Hints.ai_flags = AI_NUMERICHOST | AI_PASSIVE;
RetVal = getaddrinfo(Address, "1" /* Dummy */, &Hints, &AddrInfo);
if (RetVal != 0) {
fprintf(stderr, "getaddrinfo failed with error %d: %s\n",
RetVal, gai_strerror(RetVal));
WSACleanup();
return -1;
}
//
// For each address getaddrinfo returned, we create a new socket,
// bind that address to it, and create a queue to listen on.
//
for (i = 0, AI = AddrInfo; AI != NULL; AI = AI->ai_next) {
// Highly unlikely, but check anyway.
if (i == FD_SETSIZE) {
printf("getaddrinfo returned more addresses than we could use.\n");
break;
}
ServSock[i] = socket(AI->ai_family, SOCK_RAW, Protocol);
if (ServSock[i] == INVALID_SOCKET){
fprintf(stderr, "socket() failed with error %d: %s\n",
WSAGetLastError(), DecodeError(WSAGetLastError()));
continue;
}
//
// bind() associates a local address and port combination
// with the socket just created. This is most useful when
// the application is a server that has a well-known port
// that clients know about in advance.
//
if (bind(ServSock[i], AI->ai_addr, AI->ai_addrlen) == SOCKET_ERROR) {
fprintf(stderr,"bind() failed with error %d: %s\n",
WSAGetLastError(), DecodeError(WSAGetLastError()));
closesocket(ServSock[i]);
continue;
}
i++;
printf("Listening on protocol %d\n", Protocol);
}
freeaddrinfo(AddrInfo);
if (i == 0) {
fprintf(stderr, "Fatal error: unable to serve on any address.\n");
WSACleanup();
return -1;
}
NumSocks = i;
//
// We now put the server into an eternal loop,
// serving requests as they arrive.
//
FD_ZERO(&SockSet);
while(1) {
FromLen = sizeof(From);
//
// For connection orientated protocols, we will handle the
// packets comprising a connection collectively. For datagram
// protocols, we have to handle each datagram individually.
//
//
// Check to see if we have any sockets remaining to be served
// from previous time through this loop. If not, call select()
// to wait for a connection request or a datagram to arrive.
//
for (i = 0; i < NumSocks; i++){
if (FD_ISSET(ServSock[i], &SockSet))
break;
}
if (i == NumSocks) {
for (i = 0; i < NumSocks; i++)
FD_SET(ServSock[i], &SockSet);
if (select(NumSocks, &SockSet, 0, 0, 0) == SOCKET_ERROR) {
fprintf(stderr, "select() failed with error %d: %s\n",
WSAGetLastError(), DecodeError(WSAGetLastError()));
WSACleanup();
return -1;
}
}
for (i = 0; i < NumSocks; i++){
if (FD_ISSET(ServSock[i], &SockSet)) {
FD_CLR(ServSock[i], &SockSet);
break;
}
}
AmountRead = recvfrom(ServSock[i], Buffer, sizeof(Buffer), 0,
(LPSOCKADDR)&From, &FromLen);
if (AmountRead == SOCKET_ERROR) {
fprintf(stderr, "recvfrom() failed with error %d: %s\n",
WSAGetLastError(), DecodeError(WSAGetLastError()));
closesocket(ServSock[i]);
break;
}
if (AmountRead == 0) {
// This should never happen on an unconnected socket, but...
printf("recvfrom() returned zero, aborting\n");
closesocket(ServSock[i]);
break;
}
RetVal = getnameinfo((LPSOCKADDR)&From, FromLen, Hostname,
sizeof(Hostname), NULL, 0, NI_NUMERICHOST);
if (RetVal != 0) {
fprintf(stderr, "getnameinfo() failed with error %d: %s\n",
RetVal, DecodeError(RetVal));
strcpy(Hostname, "<unknown>");
}
if (Protocol == IP_PROTOCOL_ICMPv6) {
ICMPv6Header *ICMP = (ICMPv6Header *)Buffer;
printf("Received a ICMP message from %s\n", Hostname);
printf("Type = %u, Code = %u\n", ICMP->Type, ICMP->Code);
printf("Data = \"%.*s\"\n",
AmountRead - sizeof(*ICMP), Buffer + sizeof(*ICMP));
} else {
printf("Received a %d byte datagram from %s \"%.*s\"\n",
AmountRead, Hostname, AmountRead, Buffer);
}
}
return 0;
}