tcp.c

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/* -*- c-basic-offset: 8 -*-
   rdesktop: A Remote Desktop Protocol client.
   Protocol services - TCP layer
   Copyright (C) Matthew Chapman 1999-2005

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License along
   with this program; if not, write to the Free Software Foundation, Inc.,
   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/

#if 0 // FIXME: header mess
#include <unistd.h>     /* select read write close */
#include <sys/socket.h>     /* socket connect setsockopt */
#include <sys/time.h>       /* timeval */
#include <netdb.h>      /* gethostbyname */
#include <netinet/in.h>     /* sockaddr_in */
#include <netinet/tcp.h>    /* TCP_NODELAY */
#include <arpa/inet.h>      /* inet_addr */
#include <errno.h>      /* errno */
#endif

#include "rdesktop.h"
#include <winsock2.h>

typedef int socklen_t;

#ifndef INADDR_NONE
#define INADDR_NONE ((unsigned long) -1)
#endif

/* Initialise TCP transport data packet */
STREAM
tcp_init(RDPCLIENT * This, uint32 maxlen)
{
    if (maxlen > This->tcp.out.size)
    {
        void * p;

        p = realloc(This->tcp.out.data, maxlen);

        if (p == NULL)
        {
            This->disconnect_reason = 262;
            return NULL;
        }

        This->tcp.out.data = (uint8 *)p;
        This->tcp.out.size = maxlen;
    }

    This->tcp.out.p = This->tcp.out.data;
    This->tcp.out.end = This->tcp.out.data + This->tcp.out.size;
    return &This->tcp.out;
}

/* Send TCP transport data packet */
BOOL
tcp_send(RDPCLIENT * This, STREAM s)
{
    int length = (int)(s->end - s->data);
    int total = 0;
    DWORD sent;

    OVERLAPPED overlapped;
    memset(&overlapped, 0, sizeof(overlapped));

    while (total < length)
    {
        WriteFile((HANDLE)This->tcp.sock, s->data + total, length - total, NULL, &overlapped);

        switch(WaitForSingleObjectEx((HANDLE)This->tcp.sock, INFINITE, TRUE))
        {
            /* Success */
        case WAIT_OBJECT_0:
            break;

            /* Timeout or error */
        case WAIT_TIMEOUT:
        default:
            This->disconnect_reason = 772;

            /* Aborted, must disconnect ASAP */
        case WAIT_IO_COMPLETION:
            CancelIo((HANDLE)This->tcp.sock);
            break;
        }

        /* Wait for completion. We could hang here, but we shouldn't */
        if(!GetOverlappedResult((HANDLE)This->tcp.sock, &overlapped, &sent, TRUE))
            return False;

        total += sent;
    }

    return True;
}

/* Receive a message on the TCP layer */
STREAM
tcp_recv(RDPCLIENT * This, STREAM s, uint32 length)
{
    unsigned int new_length, end_offset, p_offset;
    DWORD rcvd = 0;

    if (s == NULL)
    {
        /* read into "new" stream */
        if (length > This->tcp.in.size)
        {
            void * p = realloc(This->tcp.in.data, length);

            if(p == NULL)
            {
                This->disconnect_reason = 262;
                return NULL;
            }

            This->tcp.in.data = (uint8 *) p;
            This->tcp.in.size = length;
        }
        This->tcp.in.end = This->tcp.in.p = This->tcp.in.data;
        s = &This->tcp.in;
    }
    else
    {
        /* append to existing stream */
        new_length = (unsigned int)(s->end - s->data) + length;
        if (new_length > s->size)
        {
            void * p = realloc(s->data, new_length);

            if(p == NULL)
            {
                This->disconnect_reason = 262;
                return NULL;
            }

            p_offset = (unsigned int)(s->p - s->data);
            end_offset = (unsigned int)(s->end - s->data);
            s->data = (uint8 *) p;
            s->size = new_length;
            s->p = s->data + p_offset;
            s->end = s->data + end_offset;
        }
    }

    while (length > 0)
    {
        OVERLAPPED overlapped;
        memset(&overlapped, 0, sizeof(overlapped));

        if (!ui_select(This, This->tcp.sock))
            /* User quit */
            return NULL;

        ReadFile((HANDLE)This->tcp.sock, s->end, length, NULL, &overlapped);

        switch(WaitForSingleObjectEx((HANDLE)This->tcp.sock, INFINITE, TRUE))
        {
            /* Success */
        case WAIT_OBJECT_0:
            break;

            /* Timeout or error */
        case WAIT_TIMEOUT:
        default:
            This->disconnect_reason = 1028;

            /* Aborted, must disconnect ASAP */
        case WAIT_IO_COMPLETION:
            CancelIo((HANDLE)This->tcp.sock);
            break;
        }

        /* Wait for completion. We could hang here, but we shouldn't */
        if(!GetOverlappedResult((HANDLE)This->tcp.sock, &overlapped, &rcvd, TRUE))
            return False;

        if (rcvd == 0)
        {
            error("Connection closed\n");
            This->disconnect_reason = 2308;
            return NULL;
        }

        s->end += rcvd;
        length -= rcvd;
    }

    return s;
}

/* Establish a connection on the TCP layer */
BOOL
tcp_connect(RDPCLIENT * This, char *server)
{
    int true_value = 1;

#ifdef IPv6

    int n;
    struct addrinfo hints, *res, *ressave;
    char tcp_port_rdp_s[10];

    snprintf(tcp_port_rdp_s, 10, "%d", This->tcp_port_rdp);

    memset(&hints, 0, sizeof(struct addrinfo));
    hints.ai_family = AF_UNSPEC;
    hints.ai_socktype = SOCK_STREAM;

    if ((n = getaddrinfo(server, tcp_port_rdp_s, &hints, &res)))
    {
        error("getaddrinfo: %s\n", gai_strerror(n));
        return False;
    }

    ressave = res;
    This->tcp.sock = -1;
    while (res)
    {
        This->tcp.sock = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
        if (!(This->tcp.sock < 0))
        {
            if (connect(This->tcp.sock, res->ai_addr, res->ai_addrlen) == 0)
                break;
            close(This->tcp.sock);
            This->tcp.sock = -1;
        }
        res = res->ai_next;
    }
    freeaddrinfo(ressave);

    if (This->tcp.sock == -1)
    {
        error("%s: unable to connect\n", server);
        return False;
    }

#else /* no IPv6 support */

    struct hostent *nslookup;
    struct sockaddr_in servaddr;

    if ((nslookup = gethostbyname(server)) != NULL)
    {
        memcpy(&servaddr.sin_addr, nslookup->h_addr, sizeof(servaddr.sin_addr));
    }
    else if ((servaddr.sin_addr.s_addr = inet_addr(server)) == INADDR_NONE)
    {
        error("%s: unable to resolve host\n", server);
        This->disconnect_reason = 260;
        return False;
    }

    if ((This->tcp.sock = socket(AF_INET, SOCK_STREAM, 0)) < 0)
    {
        // error("socket: %s\n", strerror(errno)); // EOF
        return False;
    }

    servaddr.sin_family = AF_INET;
    servaddr.sin_port = htons(This->tcp_port_rdp);

    // TODO: apply connection timeout here

    if (connect(This->tcp.sock, (struct sockaddr *) &servaddr, sizeof(struct sockaddr)) < 0)
    {
        // error("connect: %s\n", strerror(errno)); // EOF
        This->disconnect_reason = 516;
        closesocket(This->tcp.sock);
        return False;
    }

#endif /* IPv6 */

    setsockopt(This->tcp.sock, IPPROTO_TCP, TCP_NODELAY, (void *) &true_value, sizeof(true_value));

    This->tcp.in.size = 4096;
    This->tcp.in.data = (uint8 *) malloc(This->tcp.in.size);

    if(This->tcp.in.data == NULL)
    {
        This->disconnect_reason = 262;
        return False;
    }

    This->tcp.out.size = 4096;
    This->tcp.out.data = (uint8 *) malloc(This->tcp.out.size);

    if(This->tcp.out.data == NULL)
    {
        This->disconnect_reason = 262;
        return False;
    }

    return True;
}

/* Disconnect on the TCP layer */
BOOL
tcp_disconnect(RDPCLIENT * This)
{
    closesocket(This->tcp.sock);
    return True;
}

wchar_t *
tcp_get_address(RDPCLIENT * This)
{
#if 0
    static char ipaddr[32];
    struct sockaddr_in sockaddr;
    socklen_t len = sizeof(sockaddr);
    if (getsockname(This->tcp.sock, (struct sockaddr *) &sockaddr, &len) == 0)
    {
        unsigned char *ip = (unsigned char *) &sockaddr.sin_addr;
        sprintf(ipaddr, "%d.%d.%d.%d", ip[0], ip[1], ip[2], ip[3]);
    }
    else
        strcpy(ipaddr, "127.0.0.1");
    return ipaddr;
#endif
    return NULL; // TODO
}

/* reset the state of the tcp layer */
/* Support for Session Directory */
void
tcp_reset_state(RDPCLIENT * This)
{
    This->tcp.sock = -1;        /* reset socket */

    /* Clear the incoming stream */
    if (This->tcp.in.data != NULL)
        free(This->tcp.in.data);
    This->tcp.in.p = NULL;
    This->tcp.in.end = NULL;
    This->tcp.in.data = NULL;
    This->tcp.in.size = 0;
    This->tcp.in.iso_hdr = NULL;
    This->tcp.in.mcs_hdr = NULL;
    This->tcp.in.sec_hdr = NULL;
    This->tcp.in.rdp_hdr = NULL;
    This->tcp.in.channel_hdr = NULL;

    /* Clear the outgoing stream */
    if (This->tcp.out.data != NULL)
        free(This->tcp.out.data);
    This->tcp.out.p = NULL;
    This->tcp.out.end = NULL;
    This->tcp.out.data = NULL;
    This->tcp.out.size = 0;
    This->tcp.out.iso_hdr = NULL;
    This->tcp.out.mcs_hdr = NULL;
    This->tcp.out.sec_hdr = NULL;
    This->tcp.out.rdp_hdr = NULL;
    This->tcp.out.channel_hdr = NULL;
}