source: vbox/trunk/src/VBox/RDP/client/tcp.c@ 8797

/* -*- 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#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 */
#include "rdesktop.h"

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

static int sock;
static struct stream in;
static struct stream out;
int g_tcp_port_rdp = TCP_PORT_RDP;

/* Initialise TCP transport data packet */
STREAM
tcp_init(uint32 maxlen)
{
        if (maxlen > out.size)
        {
                out.data = (uint8 *) xrealloc(out.data, maxlen);
                out.size = maxlen;
        }

        out.p = out.data;
        out.end = out.data + out.size;
        return &out;
}

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

        while (total < length)
        {
                sent = send(sock, s->data + total, length - total, 0);
                if (sent <= 0)
                {
                        error("send: %s\n", strerror(errno));
                        return;
                }

                total += sent;
        }
}

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

        if (s == NULL)
        {
                /* read into "new" stream */
                if (length > in.size)
                {
                        in.data = (uint8 *) xrealloc(in.data, length);
                        in.size = length;
                }
                in.end = in.p = in.data;
                s = &in;
        }
        else
        {
                /* append to existing stream */
                new_length = (s->end - s->data) + length;
                if (new_length > s->size)
                {
                        p_offset = s->p - s->data;
                        end_offset = s->end - s->data;
                        s->data = (uint8 *) xrealloc(s->data, new_length);
                        s->size = new_length;
                        s->p = s->data + p_offset;
                        s->end = s->data + end_offset;
                }
        }

        while (length > 0)
        {
                if (!ui_select(sock))
                        /* User quit */
                        return NULL;

                rcvd = recv(sock, s->end, length, 0);
                if (rcvd < 0)
                {
                        error("recv: %s\n", strerror(errno));
                        return NULL;
                }
                else if (rcvd == 0)
                {
                        error("Connection closed\n");
                        return NULL;
                }

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

        return s;
}

/* Establish a connection on the TCP layer */
BOOL
tcp_connect(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", g_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;
        sock = -1;
        while (res)
        {
                sock = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
                if (!(sock < 0))
                {
                        if (connect(sock, res->ai_addr, res->ai_addrlen) == 0)
                                break;
                        close(sock);
                        sock = -1;
                }
                res = res->ai_next;
        }
        freeaddrinfo(ressave);

        if (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);
                return False;
        }

        if ((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0)
        {
                error("socket: %s\n", strerror(errno));
                return False;
        }

        servaddr.sin_family = AF_INET;
        servaddr.sin_port = htons(g_tcp_port_rdp);

        if (connect(sock, (struct sockaddr *) &servaddr, sizeof(struct sockaddr)) < 0)
        {
                error("connect: %s\n", strerror(errno));
                close(sock);
                return False;
        }

#endif /* IPv6 */

        setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, (void *) &true_value, sizeof(true_value));

        in.size = 4096;
        in.data = (uint8 *) xmalloc(in.size);

        out.size = 4096;
        out.data = (uint8 *) xmalloc(out.size);

        return True;
}

/* Disconnect on the TCP layer */
void
tcp_disconnect(void)
{
        close(sock);
}

char *
tcp_get_address()
{
        static char ipaddr[32];
        struct sockaddr_in sockaddr;
        socklen_t len = sizeof(sockaddr);
        if (getsockname(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;
}

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

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

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