ckctel.c

KERMIT工具 这在办公室下载不了,很多人都没有载不到.

fwdx_tn_sb( unsigned char * sb, int n )
#else
fwdx_tn_sb( sb, n ) unsigned char * sb; int n;
#endif /* CK_ANSIC */
{
    unsigned short hchannel, nchannel;
    unsigned char * p;
    int i;
    int rc = -1;

    /* check to ensure we have negotiated Forward X */
    if ( sstelnet && !TELOPT_ME(TELOPT_FORWARD_X) ||
         !sstelnet && !TELOPT_U(TELOPT_FORWARD_X) ) {
        debug(F100,"fwdx_tn_sb() not negotiated","",0);
        return(0);
    }

#ifdef CK_SSL
    if (TELOPT_SB(TELOPT_START_TLS).start_tls.me_follows) {
        return(0);
    }
#endif /* CK_SSL */

    switch (sb[0]) {
    case FWDX_SCREEN:
        if (sstelnet && n == 4)
            rc = fwdx_create_listen_socket(sb[1]);
        break;
    case FWDX_OPEN:
        if ( !sstelnet && n >= 5 ) {
            p = (unsigned char *) &nchannel;
            i = 1;
            /* IAC quoting has been stripped in tn_sb() */
            p[0] = sb[i++];
            p[1] = sb[i++];
            hchannel = ntohs(nchannel);
            rc = fwdx_open_client_channel(hchannel);
            if ( rc < 0 ) {
                /* Failed; Send CLOSE channel */
                fwdx_send_close(hchannel);
                rc = 0;         /* Do not consider this to be a telnet error */
            }
#ifdef NT
            if ( !TELOPT_SB(TELOPT_FORWARD_X).forward_x.thread_started ) {
                ckThreadBegin( &fwdx_thread,32655, 0, FALSE, 0 ) ;
                TELOPT_SB(TELOPT_FORWARD_X).forward_x.thread_started = 1;
            }
#endif /* NT */
        }
        break;
    case FWDX_CLOSE:
        p = (unsigned char *) &nchannel;
        i = 1;
        /* IAC quoting has been stripped in tn_sb() */
        p[0] = sb[i++];
        p[1] = sb[i++];
        hchannel = ntohs(nchannel);
        fwdx_close_channel(hchannel);
        rc = 0; /* no errors when closing */
        break;
    case FWDX_DATA:
        p = (unsigned char *) &nchannel;
        i = 1;
        /* IAC quoting has been stripped in tn_sb() */
        p[0] = sb[i++];
        p[1] = sb[i++];
        hchannel = ntohs(nchannel);
        rc = fwdx_send_xauth_to_xserver(hchannel,(char *)&sb[3],n-5);
        if ( rc >= 0 && n-5-rc > 0) {
            rc = fwdx_write_data_to_channel(hchannel,(char *)&sb[3+rc],n-5-rc);
            if ( rc < 0 ) {
                /* Failed; Send CLOSE channel */
                rc = fwdx_send_close(hchannel);
            }
        }
        break;
    case FWDX_OPTIONS:
        if ( sstelnet ) {
#ifndef FWDX_SERVER
            rc = 0;
#else
            rc = fwdx_server_accept_options((char*)&sb[2],n-3);
#endif
        } else {
            rc = fwdx_client_reply_options((char *)&sb[2],n-3);
            if ( rc >= 0 ) {
                rc = tn_sndfwdx();
            }
        }
        break;
    case FWDX_OPT_DATA:
        switch ( sb[1] ) {
        default:
            rc = 0;             /* we don't recognize, not an error */
        }
        break;

    case FWDX_XOFF:
    case FWDX_XON:
        if ( !sstelnet ) {
            p = (unsigned char *) &nchannel;
            i = 1;
            /* IAC quoting has been stripped in tn_sb() */
            p[0] = sb[i++];
            p[1] = sb[i++];
            hchannel = ntohs(nchannel);
            TELOPT_SB(TELOPT_FORWARD_X).forward_x.channel[hchannel].suspend =
                (sb[0] == FWDX_XOFF);
            rc = 0;
        }
        break;
    }
    return(rc < 0 ? -1 : 0);
}

int
#ifdef CK_ANSIC
fwdx_send_xauth_to_xserver(int channel, unsigned char * data, int len)
#else
fwdx_send_xauth_to_xserver(channel, data, len)
    int channel; unsigned char * data; int len;
#endif /* CK_ANSIC */
{
    int name_len, data_len, i;

    for (i = 0; i < MAXFWDX ; i++) {
        if (TELOPT_SB(TELOPT_FORWARD_X).forward_x.channel[i].id == channel)
            break;
    }
    if ( i == MAXFWDX )
        goto auth_err;

    if (!TELOPT_SB(TELOPT_FORWARD_X).forward_x.channel[i].need_to_send_xauth)
        return(0);

    if (len < 12)
        goto auth_err;

    /* Parse the lengths of variable-length fields. */
    if (data[0] == 0x42) {              /* byte order MSB first. */
        /* Xauth packets appear to always have this format */
        if ( data[1] != 0x00 ||
             data[2] != 0x00 ||
             data[3] != 0x0B ||
             data[4] != 0x00 ||
             data[5] != 0x00 )
            goto auth_err;

        name_len = (data[6] << 8) + data[7];
        data_len = (data[8] << 8) + data[9];
    } else if (data[0] == 0x6c) {       /* Byte order LSB first. */
        /* Xauth packets appear to always have this format */
        if ( data[1] != 0x00 ||
             data[2] != 0x0B ||
             data[3] != 0x00 ||
             data[4] != 0x00 ||
             data[5] != 0x00 )
            goto auth_err;

        name_len = data[6] + (data[7] << 8);
        data_len = data[8] + (data[9] << 8);
    } else {
        /* bad byte order byte */
        goto auth_err;
    }

    /* Check if the whole packet is in buffer. */
    if (len < 12 + ((name_len + 3) & ~3) + ((data_len + 3) & ~3))
        goto auth_err;
    /* If the Telnet Server allows a real Xauth message to be sent */
    /* Then let the message be processed by the Xserver.           */
    if (name_len + data_len > 0) {
       TELOPT_SB(TELOPT_FORWARD_X).forward_x.channel[i].need_to_send_xauth = 0;
       return(0);
    }
    else
    /* If an empty Xauth message was received.  We are going to   */
    /* send our own Xauth message using the real Xauth data.  And */
    /* then send any other data in the buffer.                    */
    {
        int c, err, dpynum, scrnum, family, sb_len;
        char *display, *host = NULL, *rest = NULL;
        unsigned char *sb, *p;

        /* parse the local DISPLAY env var */
        display = getenv("DISPLAY");
        if ( !display )
            display = "127.0.0.1:0.0";

        if (fwdx_parse_displayname(display,
                                   &family, &host, &dpynum, &scrnum, &rest)) {
            char * disp_no = ckitoa(dpynum);    /* should be unsigned */
            if (family == FamilyLocal) {
                /* call with address = "<local host name>" */
                char address[300] = "localhost";
                gethostname(address, sizeof(address) - 1);
                real_xauth = XauGetAuthByAddr(family,
                                              strlen(address),
                                              address,
                                              strlen(disp_no),
                                              disp_no, 0, NULL);
            }
            else if (family == FamilyInternet) {
                /* call with address = 4 bytes numeric ip addr (MSB) */
                struct hostent *hi;
                if (hi = gethostbyname(host))
                    real_xauth = XauGetAuthByAddr(family, 4,
                                                  hi->h_addr, strlen(disp_no),
                                                  disp_no, 0, NULL);
            }
        }
        if (host) free(host);
        if (rest) free(rest);
        if (!real_xauth) {
    TELOPT_SB(TELOPT_FORWARD_X).forward_x.channel[i].need_to_send_xauth = 0;
            return(0);
        }

        if (!strncmp(real_xauth->name,
                     "MIT-MAGIC-COOKIE-1",
                     real_xauth->name_length)) {
            char msg[64];

            name_len = real_xauth->name_length;
            data_len = 16;

            if ( data[0] == 0x42 ) {
                msg[0] = 0x42; /* MSB order */
                msg[1] = msg[2] = 0;
                msg[3] = 0x0B;
                msg[4] = msg[5] = 0;
                msg[6] = (name_len >> 8);
                msg[7] = (name_len & 0xFF);
                msg[8] = (data_len >> 8);
                msg[9] = (data_len & 0xFF);
            } else {
                msg[0] = 0x6c; /* LSB order */
                msg[1] = 0;
                msg[2] = 0x0B;
                msg[3] = msg[4] = msg[5] = 0;
                msg[6] = (name_len & 0xFF);
                msg[7] = (name_len >> 8);
                msg[8] = (data_len & 0xFF);
                msg[9] = (data_len >> 8);
            }
            msg[10] = msg[11] = 0;
            memcpy(&msg[12],real_xauth->name,18);
            msg[30] = msg[31] = 0;
            memcpy(&msg[32],real_xauth->data,16);

            if (fwdx_write_data_to_channel(channel,(char *)msg,48) < 0) {
  TELOPT_SB(TELOPT_FORWARD_X).forward_x.channel[i].need_to_send_xauth = 0;
                return(-1);
            } else {
  TELOPT_SB(TELOPT_FORWARD_X).forward_x.channel[i].need_to_send_xauth = 0;
                return(12);
            }
        } else {
  TELOPT_SB(TELOPT_FORWARD_X).forward_x.channel[i].need_to_send_xauth = 0;
            return(0);        /* we do not know how to handle this type yet */
        }
    }

  auth_err:
        debug(F100,"fwdx_send_xauth_to_xserver error","",0);
    return(-1);
}


#ifdef COMMENT
int
#ifdef CK_ANSIC
fwdx_authorize_channel(int channel, unsigned char * data, int len)
#else
fwdx_authorize_channel(channel, data, len)
    int channel; unsigned char * data; int len;
#endif /* CK_ANSIC */
{
    /* XXX maybe we should have some retry handling if not the whole first
    * authorization packet arrives complete
    */
    if ( !TELOPT_SB(TELOPT_FORWARD_X).forward_x.channel[channel].authorized ) {
        int name_len, data_len;

        if (len < 12)
            goto auth_err;

        /* Parse the lengths of variable-length fields. */
        if (data[0] == 0x42) {          /* byte order MSB first. */
            /* Xauth packets appear to always have this format */
            if ( data[1] != 0x00 ||
                 data[2] != 0x00 ||
                 data[3] != 0x0B ||
                 data[4] != 0x00 ||
                 data[5] != 0x00 )
                goto auth_err;

            name_len = (data[6] << 8) + data[7];
            data_len = (data[8] << 8) + data[9];
        } else if (data[0] == 0x6c) {   /* Byte order LSB first. */
            /* Xauth packets appear to always have this format */
            if ( data[1] != 0x00 ||
                 data[2] != 0x0B ||
                 data[3] != 0x00 ||
                 data[4] != 0x00 ||
                 data[5] != 0x00 )
                goto auth_err;

            name_len = data[6] + (data[7] << 8);
            data_len = data[8] + (data[9] << 8);
        } else {
            /* bad byte order byte */
            goto auth_err;
        }
        /* Check if authentication protocol matches. */
        if (name_len != fake_xauth.name_length ||
             memcmp(data + 12, fake_xauth.name, name_len) != 0) {
            /* connection uses different authentication protocol */
            goto auth_err;
        }
        /* Check if authentication data matches our fake data. */
        if (data_len != fake_xauth.data_length ||
             memcmp(data + 12 + ((name_len + 3) & ~3),
                     fake_xauth.data, fake_xauth.data_length) != 0) {
            /* auth data does not match fake data */
            goto auth_err;
        }
        /* substitute the fake data with real data if we have any */
        if (real_xauth && real_xauth->data)
            memcpy(data + 12 + ((name_len + 3) & ~3),
                   real_xauth->data, data_len);

        TELOPT_SB(TELOPT_FORWARD_X).forward_x.channel[channel].authorized = 1;
    }
    return(0);
  auth_err:
    return(-1);
}
#endif /* COMMENT */

int
#ifdef CK_ANSIC
fwdx_send_close(int channel)
#else
fwdx_send_close(channel) int channel;
#endif /* CK_ANSIC */
{
    unsigned short nchannel;
    int i,rc;
    CHAR * p;

#ifdef CK_SSL
    if (TELOPT_SB(TELOPT_START_TLS).start_tls.me_follows) {
        return(0);
    }
#endif /* CK_SSL */

    nchannel = htons(channel);
    p = (unsigned char *) &nchannel;

    i = 0;
    sb_out[i++] = (CHAR) IAC;               /* I Am a Command */
    sb_out[i++] = (CHAR) SB;                /* Subnegotiation */
    sb_out[i++] = TELOPT_FORWARD_X;         /* Forward X */
    sb_out[i++] = FWDX_CLOSE;               /* Open */
    sb_out[i++] = p[0];                     /* First Byte of Channel */
    if ( p[0] == IAC )
        sb_out[i++] = IAC;
    sb_out[i++] = p[1];                     /* Second Byte of Channel */
    if ( p[1] == IAC )
        sb_out[i++] = IAC;
    sb_out[i++] = (CHAR) IAC;               /* End of Subnegotiation */
    sb_out[i++] = (CHAR) SE;                /* marked by IAC SE */
#ifdef DEBUG
    if (deblog || tn_deb || debses) {
        ckmakxmsg(fwdx_msg_out,TN_MSG_LEN,"TELNET SENT SB ",
                  TELOPT(TELOPT_FORWARD_X),
                  " CLOSE CHANNEL=",ckitoa(channel)," IAC SE",
                  NULL,NULL,NULL,NULL,NULL,NULL,NULL
                  );
    }
#endif /* DEBUG */
#ifdef OS2
    RequestTelnetMutex( SEM_INDEFINITE_WAIT );
#endif
#ifdef DEBUG
    debug(F100,fwdx_msg_out,"",0);
    if (tn_deb || debses) tn_debug(fwdx_msg_out);
#endif /* DEBUG */
    rc = (ttol((CHAR *)sb_out,i) < 0);      /* Send it. */
#ifdef OS2
    ReleaseTelnetMutex();
#endif
    if (rc)
      return(-1);
    return(0);
}

int
#ifdef CK_ANSIC
fwdx_send_open(int channel)
#else /* CK_ANSIC */
fwdx_send_open(channel) int channel;
#endif /* CK_ANSIC */
{
    unsigned short nchannel;
    int i, rc;
    CHAR * p;

#ifdef CK_SSL
    if (TELOPT_SB(TELOPT_START_TLS).start_tls.me_follows) {
        return(0);
    }