/*******************************************************************************
*
* remShellTelnetDisconn - disconnect shell from telnet
*
* This routine is called from the telnetInTask either as a result of the
* connection terminating from the remote host, or as a result of the logout()
* command issued to our shell. It is therefore always run in the context of
* the telnetInTask.
*
* The shell standard I/O is redirected back to the console, and the shell is
* restarted.
*
* RETURNS: N/A
*/
void remShellTelnetDisconn
(
int disconnArg
)
{
shellLogoutInstall ((FUNCPTR) NULL, 0); /* uninstall logout function */
if (logFdFromRlogin != NONE)
{
logFdDelete (logFdFromRlogin); /* cancel extra log device */
logFdFromRlogin = NONE; /* reset fd */
}
#if VX_VERSION == 55 || VX_VERSION == 542
shellOrigStdSet (STD_IN, shellInFd); /* restore shell's stnd I/O */
shellOrigStdSet (STD_OUT, shellOutFd);
shellOrigStdSet (STD_ERR, shellErrFd);
#endif
shellLock (FALSE); /* unlock shell */
/* For typical remote sessions, there is no need to restart the shell.
* If we are in shell context, simply restoring the standard I/O
* descriptors is enough to get the shell back on track upon return
* from this function. If we are in telnetInTask context, the closing
* of the pty device will cause the shell to unblock from its read()
* and do subsequent I/O from the restored descriptors.
* However, problems can occur upon logout if the remote user has
* disabled the line editor and/or put the pty device in raw mode.
* The problem caused is that the shell does not resume properly.
* It is therefore deemed prudent to always restart the shell, thereby
* avoiding any funny business.
*
* The previous version attempted to send a ctrl-D up the pty device
* to wakeup and restart the shell. Unfortunately, ctrl-D only has
* special meaning when the device is in line mode, and hence did
* not work in raw mode.
*
* The pty device is closed after the shell is restarted, when called
* from telnetInTask, to avoid waking the existing shell and causing an
* additional prompt to appear on the console.
*/
activeFlag = FALSE; /* allow new connection */
#if (_WRS_VXWORKS_MAJOR >= 6)
excJobAdd((VOIDFUNCPTR)shellRestart,
(int)CURRENT_SHELL_SESSION , 0, 0, 0, 0, 0);
#else
excJobAdd(shellRestart, FALSE, 0, 0, 0, 0, 0);
#endif
} /* remShellTelnetDisconn */
STATUS shellParserControl
(
UINT32 remoteEvent, /* Starting or stopping a connection? */
UINT32 sessionId, /* Unique identifier for each session */
UINT32 slaveFd /* File descriptor for character i/o */
)
{
if ((taskNameToId ("tShell")) == ERROR) /* Shell not started yet. */
return (ERROR);
if (remoteEvent == REMOTE_START)
{
/* Handle a new telnet or rlogin session. */
if (remoteId != 0) /* Failed request - only one session allowed. */
return (ERROR);
if (!shellLock (TRUE)) /* Shell is not available. */
{
fdprintf (slaveFd, "The shell is currently in use.\n");
return (ERROR);
}
/* Let the user try to login */
if (shellLogin (slaveFd) != OK)
{
shellLock (FALSE);
return (ERROR);
}
/* setup the slave device to act like a terminal */
(void) ioctl (slaveFd, FIOOPTIONS, OPT_TERMINAL);
shellLogoutInstall ((FUNCPTR) telnetdExit, sessionId);
/* get the shell's standard I/O fd's so we can restore them later */
shellInFd = ioGlobalStdGet (STD_IN);
shellOutFd = ioGlobalStdGet (STD_OUT);
shellErrFd = ioGlobalStdGet (STD_ERR);
/* set shell's standard I/O to new device; add extra logging device */
shellOrigStdSet (STD_IN, slaveFd);
shellOrigStdSet (STD_OUT, slaveFd);
shellOrigStdSet (STD_ERR, slaveFd);
logFdAdd (slaveFd);
logFdFromRlogin = slaveFd; /* store new fd for logFdSet() */
/* Store the session identifier. */
remoteId = sessionId;
/* notify the shell we have started a remote session */
shellIsRemoteConnectedSet (TRUE);
printErr ("\ntelnetd: This system *IN USE* via telnet.\n");
/* Prevent network denial of service attacks by waiting a second */
taskDelay (sysClkRateGet() / 2);
/* Restart the shell to access the redirected file descriptors. */
excJobAdd (shellRestart, TRUE, 0, 0, 0, 0, 0);
return (OK);
}
else if (remoteEvent == REMOTE_STOP)
{
/*
* End an active telnet or rlogin session. This event occurs
* after the server closes the socket.
*/
if (remoteId != sessionId) /* Unknown remote session. */
return (ERROR);
shellLogoutInstall ((FUNCPTR) NULL, 0); /* remove logout function */
if (logFdFromRlogin != NONE)
{
logFdDelete (logFdFromRlogin); /* cancel extra log device */
logFdFromRlogin = NONE; /* reset fd */
}
shellOrigStdSet (STD_IN, shellInFd); /* restore shell's stnd I/O */
shellOrigStdSet (STD_OUT, shellOutFd);
shellOrigStdSet (STD_ERR, shellErrFd);
shellLock (FALSE); /* unlock shell */
/*
* For typical remote sessions, restoring the standard I/O
* descriptors is enough to reconnect the shell to the console
* because closing the pty device will cause the shell to unblock
* from its read() and use the restored descriptors. However,
* problems can occur upon logout if the remote user has disabled
* the line editor and/or put the pty device in raw mode, so the
* shell is restarted in all cases.
*/
remoteId = 0; /* Allow a new session. */
/* notify the shell we have ended a remote session */
shellIsRemoteConnectedSet (FALSE);
excJobAdd (shellRestart, FALSE, 0, 0, 0, 0, 0);
return (OK);
}
return (ERROR); /* Ignore unknown control operations. */
}
/*******************************************************************************
*
* remShellTelnetConn - connect shell to telnet
*
* This routine is called by the telnet demon to connect the shell with the
* remote telnet user.
* Remote telnet requests will cause `stdin', `stdout', and `stderr' to be stolen
* away from the console. When the remote user disconnects, `stdin', `stdout',
* and `stderr' are restored, and the shell is restarted.
*
* RETURNS: OK or ERROR.
*/
STATUS remShellTelnetConn
(
int interpConnArg, /* argument for interpConn () */
int slaveFd,
int exitArg, /* */
int * disconnArg,
char * msg
)
{
/* wait for shell to exist */
while (taskNameToId (telnetShellName) == ERROR)
taskDelay (sysClkRateGet ());
/* check to see if there's already an active connection */
if (activeFlag)
{
strcpy(msg, "\r\nSorry, this system is engaged.\r\n");
return ERROR;
}
if (!shellLock (TRUE))
{
strcpy(msg, "\r\nSorry, shell is locked.\r\n");
printErr ("telnetd: someone tried to login into.\n");
return ERROR;
}
printErr ("\ntelnetd: This system *IN USE* via telnet.\n");
shellLogoutInstall ((FUNCPTR) telnetdExit, exitArg);
activeFlag = TRUE;
/* get the shell's standard I/O fd's so we can restore them later */
shellInFd = ioGlobalStdGet (STD_IN);
shellOutFd = ioGlobalStdGet (STD_OUT);
shellErrFd = ioGlobalStdGet (STD_ERR);
#ifndef BROADCOM_DEBUG
#if VX_VERSION == 55 || VX_VERSION == 542
/* set shell's standard I/O to pty device; add extra logging device */
shellOrigStdSet (STD_IN, slaveFd);
shellOrigStdSet (STD_OUT, slaveFd);
shellOrigStdSet (STD_ERR, slaveFd);
logFdAdd (slaveFd);
logFdFromRlogin = slaveFd; /* store pty fd for logFdSet() */
#endif
#endif /* BROADCOM_DEBUG */
/* the shell is currently stuck in a read from the console, so we
* restart it */
#ifndef BROADCOM_DEBUG
#if (_WRS_VXWORKS_MAJOR >= 6)
excJobAdd((VOIDFUNCPTR)shellRestart,
(int)CURRENT_SHELL_SESSION , 0, 0, 0, 0, 0);
#else
excJobAdd (shellRestart, TRUE, 0, 0, 0, 0, 0);
#endif
#else
sp (copyStreams, slaveFd, slaveFd,0,0,0,0,0,0,0); /* !!! */
#endif /* BROADCOM_DEBUG */
(void) ioctl (slaveFd, FIOFLUSH, 0 /*XXX*/);
return OK;
} /* remShellTelnetConn */