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Bounty program for improvements to Tcl and certain Tcl packages.

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/*
 * Copyright (C) 1997-2000 Matt Newman <[email protected]>
 *
 * $Header: /home/rkeene/tmp/cvs2fossil/../tcltls/tls/tls/tlsIO.c,v 1.8 2000/07/27 01:58:18 hobbs Exp $
 *
 * TLS (aka SSL) Channel - can be layered on any bi-directional
 * Tcl_Channel (Note: Requires Trf Core Patch)
 *
 * This was built from scratch based upon observation of OpenSSL 0.9.2B
 *
 * Addition credit is due for Andreas Kupries ([email protected]), for


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/*
 * Copyright (C) 1997-2000 Matt Newman <[email protected]>
 *
 * $Header: /home/rkeene/tmp/cvs2fossil/../tcltls/tls/tls/tlsIO.c,v 1.9 2000/08/15 00:02:08 hobbs Exp $
 *
 * TLS (aka SSL) Channel - can be layered on any bi-directional
 * Tcl_Channel (Note: Requires Trf Core Patch)
 *
 * This was built from scratch based upon observation of OpenSSL 0.9.2B
 *
 * Addition credit is due for Andreas Kupries ([email protected]), for
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			int mask));
static void	TlsChannelHandlerTimer _ANSI_ARGS_ ((ClientData clientData));

/*
 * This structure describes the channel type structure for TCP socket
 * based IO:
 */
#ifdef TCL_CHANNEL_VERSION_2
static Tcl_ChannelType tlsChannelType = {
    "tls",		/* Type name. */






    TCL_CHANNEL_VERSION_2,	/* A v2 channel (8.3.2/8.4a2+) */
    TlsCloseProc,	/* Close proc. */
    TlsInputProc,	/* Input proc. */
    TlsOutputProc,	/* Output proc. */
    NULL,		/* Seek proc. */
    NULL,		/* Set option proc. */
    TlsGetOptionProc,	/* Get option proc. */
    TlsWatchProc,	/* Initialize notifier. */
    TlsGetHandleProc,	/* Get file handle out of channel. */
    NULL,		/* Close2Proc. */
    TlsBlockModeProc,	/* Set blocking/nonblocking mode.*/
    NULL,		/* FlushProc. */
    TlsNotifyProc,	/* handlerProc. */
};
#else
static Tcl_ChannelType tlsChannelType = {
    "tls",		/* Type name. */






    TlsBlockModeProc,	/* Set blocking/nonblocking mode.*/
    TlsCloseProc,	/* Close proc. */
    TlsInputProc,	/* Input proc. */
    TlsOutputProc,	/* Output proc. */
    NULL,		/* Seek proc. */
    NULL,		/* Set option proc. */
    TlsGetOptionProc,	/* Get option proc. */
    TlsWatchProc,	/* Initialize notifier. */
    TlsGetHandleProc,	/* Get file handle out of channel. */
};
#endif

Tcl_ChannelType *Tls_ChannelType()
{

    return &tlsChannelType;



}

/*
 *-------------------------------------------------------------------
 *
 * TlsBlockModeProc --
 *






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			int mask));
static void	TlsChannelHandlerTimer _ANSI_ARGS_ ((ClientData clientData));

/*
 * This structure describes the channel type structure for TCP socket
 * based IO:
 */

static Tcl_ChannelType tlsChannelType2 = {
    "tls",		/* Type name. */
#ifndef TCL_CHANNEL_VERSION_2
    /*
     * Avoids warning in Windows compiler when compiling with 8.3.1-.
     */
    (Tcl_DriverBlockModeProc *)
#endif
    TCL_CHANNEL_VERSION_2,	/* A v2 channel (8.3.2+) */
    TlsCloseProc,	/* Close proc. */
    TlsInputProc,	/* Input proc. */
    TlsOutputProc,	/* Output proc. */
    NULL,		/* Seek proc. */
    NULL,		/* Set option proc. */
    TlsGetOptionProc,	/* Get option proc. */
    TlsWatchProc,	/* Initialize notifier. */
    TlsGetHandleProc,	/* Get file handle out of channel. */
    NULL,		/* Close2Proc. */
    TlsBlockModeProc,	/* Set blocking/nonblocking mode.*/
    NULL,		/* FlushProc. */
    TlsNotifyProc,	/* handlerProc. */
};

static Tcl_ChannelType tlsChannelType1 = {
    "tls",		/* Type name. */
#ifdef TCL_CHANNEL_VERSION_2
    /*
     * Avoids warning in Windows compiler when compiling with 8.3.2+.
     */
    (Tcl_ChannelTypeVersion)
#endif
    TlsBlockModeProc,	/* Set blocking/nonblocking mode.*/
    TlsCloseProc,	/* Close proc. */
    TlsInputProc,	/* Input proc. */
    TlsOutputProc,	/* Output proc. */
    NULL,		/* Seek proc. */
    NULL,		/* Set option proc. */
    TlsGetOptionProc,	/* Get option proc. */
    TlsWatchProc,	/* Initialize notifier. */
    TlsGetHandleProc,	/* Get file handle out of channel. */
};


Tcl_ChannelType *Tls_ChannelType()
{
    if (channelTypeVersion == TLS_CHANNEL_VERSION_2) {
	return &tlsChannelType2;
    } else {
	return &tlsChannelType1;
    }
}

/*
 *-------------------------------------------------------------------
 *
 * TlsBlockModeProc --
 *
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    State *statePtr = (State *) instanceData;

    if (mode == TCL_MODE_NONBLOCKING) {
	statePtr->flags |= TLS_TCL_ASYNC;
    } else {
	statePtr->flags &= ~(TLS_TCL_ASYNC);
    }
#ifdef TCL_CHANNEL_VERSION_2
    return 0;
#else
    return Tcl_SetChannelOption(statePtr->interp, Tls_GetParent(statePtr),
		"-blocking", (mode == TCL_MODE_NONBLOCKING) ? "0" : "1");
#endif

}

/*
 *-------------------------------------------------------------------
 *
 * TlsCloseProc --
 *






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    State *statePtr = (State *) instanceData;

    if (mode == TCL_MODE_NONBLOCKING) {
	statePtr->flags |= TLS_TCL_ASYNC;
    } else {
	statePtr->flags &= ~(TLS_TCL_ASYNC);
    }
    if (channelTypeVersion == TLS_CHANNEL_VERSION_2) {
	return 0;
    } else {
	return Tcl_SetChannelOption(statePtr->interp, Tls_GetParent(statePtr),
		"-blocking", (mode == TCL_MODE_NONBLOCKING) ? "0" : "1");

    }
}

/*
 *-------------------------------------------------------------------
 *
 * TlsCloseProc --
 *
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TlsCloseProc(ClientData instanceData,	/* The socket to close. */
             Tcl_Interp *interp)	/* For error reporting - unused. */
{
    State *statePtr = (State *) instanceData;

    dprintf(stderr,"\nTlsCloseProc(0x%x)", statePtr);

#ifndef TCL_CHANNEL_VERSION_2
    /*
     * Remove event handler to underlying channel, this could
     * be because we are closing for real, or being "unstacked".
     */

    Tcl_DeleteChannelHandler(Tls_GetParent(statePtr),
	TlsChannelHandler, (ClientData) statePtr);
#endif


    Tls_Clean(statePtr);
    Tcl_EventuallyFree((ClientData)statePtr, Tls_Free);
    return TCL_OK;
}

/*






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TlsCloseProc(ClientData instanceData,	/* The socket to close. */
             Tcl_Interp *interp)	/* For error reporting - unused. */
{
    State *statePtr = (State *) instanceData;

    dprintf(stderr,"\nTlsCloseProc(0x%x)", statePtr);

    if (channelTypeVersion == TLS_CHANNEL_VERSION_1) {
	/*
	 * Remove event handler to underlying channel, this could
	 * be because we are closing for real, or being "unstacked".
	 */

	Tcl_DeleteChannelHandler(Tls_GetParent(statePtr),
		TlsChannelHandler, (ClientData) statePtr);

    }

    Tls_Clean(statePtr);
    Tcl_EventuallyFree((ClientData)statePtr, Tls_Free);
    return TCL_OK;
}

/*
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 *-------------------------------------------------------------------
 *
 * TlsGetOptionProc --
 *
 *	Computes an option value for a SSL socket based channel, or a
 *	list of all options and their values.
 *
 *	Note: This code is based on code contributed by John Haxby.
 *
 * Results:
 *	A standard Tcl result. The value of the specified option or a
 *	list of all options and	their values is returned in the
 *	supplied DString.
 *
 * Side effects:
 *	None.
 *
 *-------------------------------------------------------------------
 */
static int
TlsGetOptionProc(ClientData instanceData,	/* Socket state. */
                 Tcl_Interp *interp,		/* For errors - can be NULL. */
                 char *optionName,		/* Name of the option to
                                                 * retrieve the value for, or
                                                 * NULL to get all options and
                                                 * their values. */
                 Tcl_DString *dsPtr)	         /* Where to store the computed value
                                                  * initialized by caller. */
{
#ifdef TCL_CHANNEL_VERSION_2
    State *statePtr = (State *) instanceData;


    Tcl_Channel downChan = Tls_GetParent(statePtr);
    Tcl_DriverGetOptionProc *getOptionProc;

    getOptionProc = Tcl_ChannelGetOptionProc(Tcl_GetChannelType(downChan));
    if (getOptionProc != NULL) {
	return (*getOptionProc)(Tcl_GetChannelInstanceData(downChan),
		interp, optionName, dsPtr);
    } else if (optionName == (char*) NULL) {
	/*
	 * Request is query for all options, this is ok.
	 */
























	return TCL_OK;
    }
    /*
     * Request for a specific option has to fail, we don't have any.
     */
    return TCL_ERROR;
#else
    State *statePtr = (State *) instanceData;
    size_t len = 0;

    if (optionName != (char *) NULL) {
        len = strlen(optionName);
    }
#if 0
    if ((len == 0) ||
        ((len > 1) && (optionName[1] == 'c') &&
         (strncmp(optionName, "-cipher", len) == 0))) {
        if (len == 0) {
            Tcl_DStringAppendElement(dsPtr, "-cipher");
        }
        Tcl_DStringAppendElement(dsPtr, SSL_get_cipher(statePtr->ssl));
        if (len) {
            return TCL_OK;
        }
    }
#endif
    return TCL_OK;
#endif
}

/*
 *-------------------------------------------------------------------
 *
 * TlsWatchProc --
 *






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 *-------------------------------------------------------------------
 *
 * TlsGetOptionProc --
 *
 *	Computes an option value for a SSL socket based channel, or a
 *	list of all options and their values.
 *


 * Results:
 *	A standard Tcl result. The value of the specified option or a
 *	list of all options and	their values is returned in the
 *	supplied DString.
 *
 * Side effects:
 *	None.
 *
 *-------------------------------------------------------------------
 */
static int
TlsGetOptionProc(ClientData instanceData,	/* Socket state. */
	Tcl_Interp *interp,		/* For errors - can be NULL. */
	char *optionName,		/* Name of the option to
					 * retrieve the value for, or
					 * NULL to get all options and
					 * their values. */
	Tcl_DString *dsPtr)		/* Where to store the computed value
					 * initialized by caller. */
{

    State *statePtr = (State *) instanceData;

    if (channelTypeVersion == TLS_CHANNEL_VERSION_2) {
	Tcl_Channel downChan = Tls_GetParent(statePtr);
	Tcl_DriverGetOptionProc *getOptionProc;

	getOptionProc = Tcl_ChannelGetOptionProc(Tcl_GetChannelType(downChan));
	if (getOptionProc != NULL) {
	    return (*getOptionProc)(Tcl_GetChannelInstanceData(downChan),
		    interp, optionName, dsPtr);
	} else if (optionName == (char*) NULL) {
	    /*
	     * Request is query for all options, this is ok.
	     */
	    return TCL_OK;
	}
	/*
	 * Request for a specific option has to fail, we don't have any.
	 */
	return TCL_ERROR;
    } else {
	size_t len = 0;

	if (optionName != (char *) NULL) {
	    len = strlen(optionName);
	}
#if 0
	if ((len == 0) || ((len > 1) && (optionName[1] == 'c') &&
		(strncmp(optionName, "-cipher", len) == 0))) {
	    if (len == 0) {
		Tcl_DStringAppendElement(dsPtr, "-cipher");
	    }
	    Tcl_DStringAppendElement(dsPtr, SSL_get_cipher(statePtr->ssl));
	    if (len) {
		return TCL_OK;
	    }
	}
#endif
	return TCL_OK;
    }


























}

/*
 *-------------------------------------------------------------------
 *
 * TlsWatchProc --
 *
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TlsWatchProc(ClientData instanceData,	/* The socket state. */
             int mask)			/* Events of interest; an OR-ed
                                         * combination of TCL_READABLE,
                                         * TCL_WRITABLE and TCL_EXCEPTION. */
{
    State *statePtr = (State *) instanceData;

#ifdef TCL_CHANNEL_VERSION_2
    Tcl_Channel     downChan;

    statePtr->watchMask = mask;

    /* No channel handlers any more. We will be notified automatically
     * about events on the channel below via a call to our
     * 'TransformNotifyProc'. But we have to pass the interest down now.
     * We are allowed to add additional 'interest' to the mask if we want
     * to. But this transformation has no such interest. It just passes
     * the request down, unchanged.
     */

    downChan = Tls_GetParent(statePtr);

    (Tcl_GetChannelType(downChan))
	->watchProc(Tcl_GetChannelInstanceData(downChan), mask);

    /*
     * Management of the internal timer.
     */

    if (statePtr->timer != (Tcl_TimerToken) NULL) {
        Tcl_DeleteTimerHandler(statePtr->timer);
	statePtr->timer = (Tcl_TimerToken) NULL;
    }
    if ((mask & TCL_READABLE) && Tcl_InputBuffered(statePtr->self) > 0) {
        /*
	 * There is interest in readable events and we actually have
	 * data waiting, so generate a timer to flush that.
	 */
	statePtr->timer = Tcl_CreateTimerHandler(TLS_TCL_DELAY,
		TlsChannelHandlerTimer, (ClientData) statePtr);
    }
#else
    if (mask == statePtr->watchMask)
	return;

    if (statePtr->watchMask) {
	/*
	 * Remove event handler to underlying channel, this could
	 * be because we are closing for real, or being "unstacked".
	 */























	Tcl_DeleteChannelHandler(Tls_GetParent(statePtr),
		TlsChannelHandler, (ClientData) statePtr);
    }
    statePtr->watchMask = mask;
    if (statePtr->watchMask) {
	/*
	 * Setup active monitor for events on underlying Channel.
	 */

	Tcl_CreateChannelHandler(Tls_GetParent(statePtr),
		statePtr->watchMask, TlsChannelHandler, (ClientData) statePtr);

    }
#endif

}

/*
 *-------------------------------------------------------------------
 *
 * TlsGetHandleProc --
 *






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TlsWatchProc(ClientData instanceData,	/* The socket state. */
             int mask)			/* Events of interest; an OR-ed
                                         * combination of TCL_READABLE,
                                         * TCL_WRITABLE and TCL_EXCEPTION. */
{
    State *statePtr = (State *) instanceData;

    if (channelTypeVersion == TLS_CHANNEL_VERSION_2) {
	Tcl_Channel     downChan;

	statePtr->watchMask = mask;

	/* No channel handlers any more. We will be notified automatically
	 * about events on the channel below via a call to our
	 * 'TransformNotifyProc'. But we have to pass the interest down now.
	 * We are allowed to add additional 'interest' to the mask if we want
	 * to. But this transformation has no such interest. It just passes
	 * the request down, unchanged.
	 */

	downChan = Tls_GetParent(statePtr);

	(Tcl_GetChannelType(downChan))
	    ->watchProc(Tcl_GetChannelInstanceData(downChan), mask);

	/*
	 * Management of the internal timer.






















	 */

	if (statePtr->timer != (Tcl_TimerToken) NULL) {
	    Tcl_DeleteTimerHandler(statePtr->timer);
	    statePtr->timer = (Tcl_TimerToken) NULL;
	}
	if ((mask & TCL_READABLE) && Tcl_InputBuffered(statePtr->self) > 0) {
	    /*
	     * There is interest in readable events and we actually have
	     * data waiting, so generate a timer to flush that.
	     */
	    statePtr->timer = Tcl_CreateTimerHandler(TLS_TCL_DELAY,
		    TlsChannelHandlerTimer, (ClientData) statePtr);
	}
    } else {
	if (mask == statePtr->watchMask)
	    return;

	if (statePtr->watchMask) {
	    /*
	     * Remove event handler to underlying channel, this could
	     * be because we are closing for real, or being "unstacked".
	     */

	    Tcl_DeleteChannelHandler(Tls_GetParent(statePtr),
		    TlsChannelHandler, (ClientData) statePtr);
	}
	statePtr->watchMask = mask;
	if (statePtr->watchMask) {
	    /*
	     * Setup active monitor for events on underlying Channel.
	     */

	    Tcl_CreateChannelHandler(Tls_GetParent(statePtr),
		    statePtr->watchMask, TlsChannelHandler,
		    (ClientData) statePtr);
	}

    }
}

/*
 *-------------------------------------------------------------------
 *
 * TlsGetHandleProc --
 *
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	Tcl_DeleteTimerHandler(statePtr->timer);
	statePtr->timer = (Tcl_TimerToken) NULL;
    }

    return mask;
}

#ifndef TCL_CHANNEL_VERSION_2
/*
 *------------------------------------------------------*
 *
 *      TlsChannelHandler --
 *
 *      ------------------------------------------------*
 *      Handler called by Tcl as a result of






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	Tcl_DeleteTimerHandler(statePtr->timer);
	statePtr->timer = (Tcl_TimerToken) NULL;
    }

    return mask;
}


/*
 *------------------------------------------------------*
 *
 *      TlsChannelHandler --
 *
 *      ------------------------------------------------*
 *      Handler called by Tcl as a result of
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	 * Data is waiting, flush it out in short time
	 */
	statePtr->timer = Tcl_CreateTimerHandler(TLS_TCL_DELAY,
		TlsChannelHandlerTimer, (ClientData) statePtr);
    }
    Tcl_Release( (ClientData)statePtr);
}
#endif

/*
 *------------------------------------------------------*
 *
 *	TlsChannelHandlerTimer --
 *
 *	------------------------------------------------*






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	 * Data is waiting, flush it out in short time
	 */
	statePtr->timer = Tcl_CreateTimerHandler(TLS_TCL_DELAY,
		TlsChannelHandlerTimer, (ClientData) statePtr);
    }
    Tcl_Release( (ClientData)statePtr);
}


/*
 *------------------------------------------------------*
 *
 *	TlsChannelHandlerTimer --
 *
 *	------------------------------------------------*
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    }
}

Tcl_Channel
Tls_GetParent( statePtr )
    State *statePtr;
{
#ifdef TCL_CHANNEL_VERSION_2
    return Tcl_GetStackedChannel(statePtr->self);
#else
#if TCL_MAJOR_VERSION == 8 && TCL_MINOR_VERSION < 2
    return statePtr->parent;
#else
    /* The reason for the existence of this procedure is
     * the fact that stacking a transform over another
     * transform will leave our internal pointer unchanged,
     * and thus pointing to the new transform, and not the
     * Channel structure containing the saved state of this
     * transform. This is the price to pay for leaving
     * Tcl_Channel references intact. The only other solution
     * is an extension of Tcl_ChannelType with another driver
     * procedure to notify a Channel about the (un)stacking.
     *
     * It walks the chain of Channel structures until it
     * finds the one pointing having 'ctrl' as instanceData
     * and then returns the superceding channel to that. (AK)
     */
 
    Tcl_Channel self = statePtr->self;
    Tcl_Channel next;




















    while ((ClientData) statePtr != Tcl_GetChannelInstanceData (self)) {
	next = Tcl_GetStackedChannel (self);
	if (next == (Tcl_Channel) NULL) {
	    /* 09/24/1999 Unstacking bug,
	     * found by Matt Newman <[email protected]>.
	     *
	     * We were unable to find the channel structure for this
	     * transformation in the chain of stacked channel. This
	     * means that we are currently in the process of unstacking
	     * it *and* there were some bytes waiting which are now
	     * flushed. In this situation the pointer to the channel
	     * itself already refers to the parent channel we have to
	     * write the bytes into, so we return that.
	     */
	    return statePtr->self;
	}
	self = next;
    }

    return Tcl_GetStackedChannel (self);
#endif
#endif
}






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    }
}

Tcl_Channel
Tls_GetParent( statePtr )
    State *statePtr;
{
    if (channelTypeVersion == TLS_CHANNEL_VERSION_2) {
	return Tcl_GetStackedChannel(statePtr->self);
    } else {



	/* The reason for the existence of this procedure is
	 * the fact that stacking a transform over another
	 * transform will leave our internal pointer unchanged,
	 * and thus pointing to the new transform, and not the
	 * Channel structure containing the saved state of this
	 * transform. This is the price to pay for leaving
	 * Tcl_Channel references intact. The only other solution
	 * is an extension of Tcl_ChannelType with another driver
	 * procedure to notify a Channel about the (un)stacking.
	 *
	 * It walks the chain of Channel structures until it
	 * finds the one pointing having 'ctrl' as instanceData
	 * and then returns the superceding channel to that. (AK)
	 */

	Tcl_Channel self = statePtr->self;
	Tcl_Channel next;

	while ((ClientData) statePtr != Tcl_GetChannelInstanceData (self)) {
	    next = Tcl_GetStackedChannel (self);
	    if (next == (Tcl_Channel) NULL) {
		/* 09/24/1999 Unstacking bug,
		 * found by Matt Newman <[email protected]>.
		 *
		 * We were unable to find the channel structure for this
		 * transformation in the chain of stacked channel. This
		 * means that we are currently in the process of unstacking
		 * it *and* there were some bytes waiting which are now
		 * flushed. In this situation the pointer to the channel
		 * itself already refers to the parent channel we have to
		 * write the bytes into, so we return that.
		 */
		return statePtr->self;
	    }
	    self = next;
	}


	return Tcl_GetStackedChannel (self);













    }

}