tracert.cpp

这个是网络编程

// Sample: IPv4 and IPv6 Trace Route Sample
//
// Files:
//    iphdr.h       - IPv4 and IPv6 packet header definitions
//    tracert.cpp   - this file
//    resolve.cpp   - Common name resolution routine
//    resolve.h     - Header file for common name resolution routines
//
// Description:
//    This sample illustrates how to use raw sockets to send ICMP
//    echo requests and receive their response in order to determine the
//    route to a particular destination. This sample performs
//    both IPv4 and IPv6 trace route operations. When using raw sockets,
//    the protocol value supplied to the socket API is used as the
//    protocol field (or next header field) of the IP packet. Then
//    as a part of the data submitted to sendto, we include both
//    the ICMP request and data. We start by setting the TTL value to one
//    and sending a request. When an intermediate router intercepts the
//    packet the TTL is decremented. If the value is zero, it sends an
//    ICMP TTL expired message which we receive. From the IP packet's
//    source field we have a location in the route to the destination.
//    With each send, the TTL is incremented by one until the specified
//    destination is reached.
//
// Compile:
//      cl -o tracert.exe tracert.cpp resolve.cpp ws2_32.lib
//
// Command Line Options/Parameters:
//     tracert.exe [-a 4|6] [-d] [-h ttl] [-w timeout] [host]
//     
//     -a       Address family (IPv4 or IPv6)
//     -d       Do not resolve the addresses to hostnames
//     -h ttl   Maximum TTL value
//     -w time  Timeout in milliseconds to wait for a response
//     host     Hostname or literal address
//
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif

#include <winsock2.h>
#include <ws2tcpip.h>
#include <stdio.h>
#include <stdlib.h>

#include "resolve.h"

#include "iphdr.h"

#define DEFAULT_DATA_SIZE      32       // default data size

#define DEFAULT_RECV_TIMEOUT   6000     // six second

#define DEFAULT_TTL            30       // default timeout

/*
 *  Global variables
 */
int   gAddressFamily = AF_UNSPEC,         // Address family to use
      gProtocol      = IPPROTO_ICMP,      // Protocol value
      gTtl           = DEFAULT_TTL,       // Default TTL value
      gTimeout       = DEFAULT_RECV_TIMEOUT; // Amount of data to send
BOOL  bResolve       = TRUE;              // Resolve addresses to host names
char *gDestination   = NULL;              // Destination

//
// Function: usage
//
// Description:
//    Print usage information.
//
void usage(char *progname)
{
    printf("usage: ping -r <host> [data size]\n");
    printf("       -a 4|6       Address family\n");
    printf("       -d           Do not resolve addresses to hostnames\n");
    printf("       -h ttl       Maximum hops to search for target\n");
    printf("       -w timeout   Wait timeout in milliseconds for each reply\n");
    printf("        host        Remote machine to ping\n");
    ExitProcess(-1);
}

// 
// Function: InitIcmpHeader
//
// Description:
//    Helper function to fill in various stuff in our ICMP request.
//
void InitIcmpHeader(char *buf, int datasize)
{
    ICMP_HDR   *icmp_hdr=NULL;
    char       *datapart=NULL;

    icmp_hdr = (ICMP_HDR *)buf;
    icmp_hdr->icmp_type     = ICMPV4_ECHO_REQUEST_TYPE;        // request an ICMP echo
    icmp_hdr->icmp_code     = ICMPV4_ECHO_REQUEST_CODE;
    icmp_hdr->icmp_id       = (USHORT)GetCurrentProcessId();
    icmp_hdr->icmp_checksum = 0;
    icmp_hdr->icmp_sequence = 0;
    icmp_hdr->icmp_timestamp= GetTickCount();
  
    datapart = buf + sizeof(ICMP_HDR);
    //
    // Place some junk in the buffer.
    //
    memset(datapart, 'E', datasize);
}

//
// Function: InitIcmp6Header
//
// Description:
//    Initialize the ICMP6 header as well as the echo request header.
//
int InitIcmp6Header(char *buf, int datasize)
{
    ICMPV6_HDR          *icmp6_hdr=NULL;
    ICMPV6_ECHO_REQUEST *icmp6_req=NULL;
    char                *datapart=NULL;

    // Initialize the ICMP6 headerf ields
    icmp6_hdr = (ICMPV6_HDR *)buf;
    icmp6_hdr->icmp6_type     = ICMPV6_ECHO_REQUEST_TYPE;
    icmp6_hdr->icmp6_code     = ICMPV6_ECHO_REQUEST_CODE;
    icmp6_hdr->icmp6_checksum = 0;

    // Initialize the echo request fields
    icmp6_req = (ICMPV6_ECHO_REQUEST *)(buf + sizeof(ICMPV6_HDR));
    icmp6_req->icmp6_echo_id       = (USHORT)GetCurrentProcessId();
    icmp6_req->icmp6_echo_sequence = 0;

    datapart = (char *)buf + sizeof(ICMPV6_HDR) + sizeof(ICMPV6_ECHO_REQUEST);

    memset(datapart, '#', datasize);

    return (sizeof(ICMPV6_HDR) + sizeof(ICMPV6_ECHO_REQUEST));
}

// 
// Function: checksum
//
// Description:
//    This function calculates the 16-bit one's complement sum
//    of the supplied buffer (ICMP) header.
//
USHORT checksum(USHORT *buffer, int size) 
{
    unsigned long cksum=0;

    while (size > 1) 
    {
        cksum += *buffer++;
        size -= sizeof(USHORT);
    }
    if (size) 
    {
        cksum += *(UCHAR*)buffer;
    }
    cksum = (cksum >> 16) + (cksum & 0xffff);
    cksum += (cksum >>16);
    return (USHORT)(~cksum);
}

//
// Function: ValidateArgs
//
// Description:
//    Parse the command line arguments.
//
void ValidateArgs(int argc, char **argv)
{
    int                i;

    for(i=1; i < argc ;i++)
    {
        if ((argv[i][0] == '-') || (argv[i][0] == '/'))
        {
            switch (tolower(argv[i][1]))
            {
                case 'a':        // address family
                    if (i+1 >= argc)
                        usage(argv[0]);
                    if (argv[i+1][0] == '4')
                        gAddressFamily = AF_INET;
                    else if (argv[i+1][0] == '6')
                        gAddressFamily = AF_INET6;
                    else
                        usage(argv[0]);
                    i++;
                    break;
                case 'd':        // Don't resolve addresses
                    bResolve = FALSE;
                    break;
                case 'h':        // Set TTL value
                    if (i+1 >= argc)
                        usage(argv[0]);
                    gTtl = atoi(argv[++i]);
                    break;
                case 'w':        // Timeout in milleseconds for each reply
                    if (i+1 >= argc)
                        usage(argv[0]);
                    gTimeout = atoi(argv[++i]);
                    break;
                default:
                    usage(argv[0]);
                    break;
            }
        }
        else
        {
            gDestination = argv[i];
        }
    }
    return;
}

//
// Function: SetIcmpSequence
//
// Description:
//    This routine sets the sequence number of the ICMP request packet.
//
void SetIcmpSequence(char *buf)
{
    ULONG    sequence=0;

    sequence = GetTickCount();
    if (gAddressFamily == AF_INET)
    {
        ICMP_HDR    *icmpv4=NULL;

        icmpv4 = (ICMP_HDR *)buf;

        icmpv4->icmp_sequence = (USHORT)sequence;
    }
    else if (gAddressFamily == AF_INET6)
    {
        ICMPV6_HDR          *icmpv6=NULL;
        ICMPV6_ECHO_REQUEST *req6=NULL;

        icmpv6 = (ICMPV6_HDR *)buf;
        req6   = (ICMPV6_ECHO_REQUEST *)(buf + sizeof(ICMPV6_HDR));

        req6->icmp6_echo_sequence = (USHORT)sequence;
    }
}

//
// Function: ComputeIcmp6PseudoHeaderChecksum
//
// Description:
//    This routine computes the ICMP6 checksum which includes the pseudo
//    header of the IPv6 header (see RFC2460 and RFC2463). The one difficulty
//    here is we have to know the source and destination IPv6 addresses which
//    will be contained in the IPv6 header in order to compute the checksum.
//    To do this we call the SIO_ROUTING_INTERFACE_QUERY ioctl to find which
//    local interface for the outgoing packet.
//
USHORT ComputeIcmp6PseudoHeaderChecksum(SOCKET s, char *icmppacket, int icmplen, struct addrinfo *dest)
{
    SOCKADDR_STORAGE localif;
    DWORD            bytes;
    char             tmp[65535],
                    *ptr=NULL,
                     proto=0,
                     zero=0;
    int              rc, total, length, i;

    // Find out which local interface for the destination
    rc = WSAIoctl(
            s,
            SIO_ROUTING_INTERFACE_QUERY,
            dest->ai_addr,
            dest->ai_addrlen,
            (SOCKADDR *)&localif,
            sizeof(localif),
           &bytes,
            NULL,
            NULL
            );
    if (rc == SOCKET_ERROR)
    {
        fprintf(stderr, "WSAIoctl failed: %d\n", WSAGetLastError());
        return -1;
    }

    // We use a temporary buffer to calculate the pseudo header. 
    ptr = tmp;
    total = 0;

    // Copy source address
    memcpy(ptr, &((SOCKADDR_IN6 *)&localif)->sin6_addr, sizeof(struct in6_addr));
    ptr   += sizeof(struct in6_addr);
    total += sizeof(struct in6_addr);

    // Copy destination address
    memcpy(ptr, &((SOCKADDR_IN6 *)dest->ai_addr)->sin6_addr, sizeof(struct in6_addr));
    ptr   += sizeof(struct in6_addr);
    total += sizeof(struct in6_addr);

    // Copy ICMP packet length
    length = htonl(icmplen);

    memcpy(ptr, &length, sizeof(length));
    ptr   += sizeof(length);
    total += sizeof(length);

    // Zero the 3 bytes
    memset(ptr, 0, 3);
    ptr   += 3;
    total += 3;

    // Copy next hop header
    proto = IPPROTO_ICMP6;

    memcpy(ptr, &proto, sizeof(proto));
    ptr   += sizeof(proto);
    total += sizeof(proto);

    // Copy the ICMP header and payload
    memcpy(ptr, icmppacket, icmplen);
    ptr   += icmplen;
    total += icmplen;

    for(i=0; i < icmplen%2 ;i++)
    {
        *ptr = 0;
        ptr++;
        total++;
    }

    return checksum((USHORT *)tmp, total);
}

//
// Function: ComputeIcmpChecksum
//
// Description:
//    This routine computes the checksum for the ICMP request. For IPv4 its
//    easy, just compute the checksum for the ICMP packet and data. For IPv6,
//    its more complicated. The pseudo checksum has to be computed for IPv6
//    which includes the ICMP6 packet and data plus portions of the IPv6
//    header which is difficult since we aren't building our own IPv6
//    header.
//
void ComputeIcmpChecksum(SOCKET s, char *buf, int packetlen, struct addrinfo *dest)
{
    if (gAddressFamily == AF_INET)
    {
        ICMP_HDR    *icmpv4=NULL;

        icmpv4 = (ICMP_HDR *)buf;
        icmpv4->icmp_checksum = 0;
        icmpv4->icmp_checksum = checksum((USHORT *)buf, packetlen);
    }
    else if (gAddressFamily == AF_INET6)
    {
        ICMPV6_HDR  *icmpv6=NULL;

        icmpv6 = (ICMPV6_HDR *)buf;
        icmpv6->icmp6_checksum = 0;
        icmpv6->icmp6_checksum = ComputeIcmp6PseudoHeaderChecksum(
                s,
                buf,
                packetlen,
                dest
                );
    }
}

//
// Function: PostRecvfrom
//
// Description:
//    This routine posts an overlapped WSARecvFrom on the raw socket.
//
int PostRecvfrom(SOCKET s, char *buf, int buflen, SOCKADDR *from, int *fromlen, WSAOVERLAPPED *ol)
{
    WSABUF  wbuf;
    DWORD   flags,
            bytes;
    int     rc;

    wbuf.buf = buf;
    wbuf.len = buflen;

    flags = 0;

    rc = WSARecvFrom(
            s,
           &wbuf,
            1,
           &bytes,
           &flags,
            from,
            fromlen,
            ol,
            NULL