/*
 * Copyright (C) 1997-2000 Matt Newman <[email protected]>
 * Copyright (C) 2000 Ajuba Solutions
 *
 * $Header: /home/rkeene/tmp/cvs2fossil/../tcltls/tls/tls/tlsIO.c,v 1.10 2000/08/15 18:49:30 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
 * providing the Tcl_ReplaceChannel mechanism and working closely with me
 * to enhance it to support full fileevent semantics.
 *
 * Also work done by the follow people provided the impetus to do this "right":
 *	tclSSL (Colin McCormack, Shared Technology)
 *	SSLtcl (Peter Antman)
 *
 */

#include "tlsInt.h"









/*
 * Forward declarations
 */

static int	TlsBlockModeProc _ANSI_ARGS_((ClientData instanceData,
			int mode));
static int	TlsCloseProc _ANSI_ARGS_ ((ClientData instanceData,

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

/*
 * This structure describes the channel type structure for TCP socket
 * based IO.  These are what the structures should look like, but we
 * have to build them up at runtime to be correct depending on whether
 * we are loaded into an 8.2.0-8.3.1 or 8.3.2+ Tcl interpreter.
 */
#ifdef TLS_STATIC_STRUCTURES_NOT_USED
static Tcl_ChannelType tlsChannelType2 = {
    "tls",		/* Type name. */






    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. */






    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. */
};
#else
static Tcl_ChannelType *tlsChannelType = NULL;
#endif

/*
 *-------------------------------------------------------------------
 *
 * Tls_ChannelType --
 *
 *	Return the correct TLS channel driver info
 *
 * Results:
 *	The correct channel driver for the current version of Tcl.
 *
 * Side effects:
 *	None.
 *
 *-------------------------------------------------------------------
 */
Tcl_ChannelType *Tls_ChannelType()
{
    /*
     * Initialize the channel type if necessary
     */
    if (tlsChannelType == NULL) {
	/*
	 * Allocation of a new channeltype structure is not easy, because of
	 * the various verson of the core and subsequent changes to the
	 * structure. The main challenge is to allocate enough memory for
	 * odern versions even if this extyension is compiled against one
	 * of the older variant!
	 *
	 * (1) Versions before stubs (8.0.x) are simple, because they are
	 *     supported only if the extension is compiled against exactly
	 *     that version of the core.
	 *
	 * (2) With stubs we just determine the difference between the older
	 *     and modern variant and overallocate accordingly if compiled
	 *     against an older variant.
	 */

	int size = sizeof(Tcl_ChannelType); /* Base size */

	/*
	 * Size of a procedure pointer. We assume that all procedure
	 * pointers are of the same size, regardless of exact type
	 * (arguments and return values).
	 *
	 * 8.2.   First version containing close2proc. Baseline.
	 * 8.3.2  Three additional vectors. Moved blockMode, new flush- and
	 *        handlerProc's.
	 *
	 * => Compilation against earlier version has to overallocate three
	 *    procedure pointers.
	 */

#ifdef EMULATE_CHANNEL_VERSION_2
	size += 3 * procPtrSize;
#endif

	tlsChannelType = (Tcl_ChannelType *) ckalloc(size);
	memset((VOID *) tlsChannelType, 0, size);

	/*
	 * Common elements of the structure (no changes in location or name)
	 * close2Proc, seekProc, setOptionProc stay NULL.
	 */

	tlsChannelType->closeProc        = TlsCloseProc;
	tlsChannelType->inputProc        = TlsInputProc;
	tlsChannelType->outputProc       = TlsOutputProc;
	tlsChannelType->getOptionProc    = TlsGetOptionProc;
	tlsChannelType->watchProc        = TlsWatchProc;
	tlsChannelType->getHandleProc    = TlsGetHandleProc;

	/*
	 * blockModeProc is a twister.  We have to make some runtime-choices,
	 * depending on the version we compiled against.
	 */

#ifdef EMULATE_CHANNEL_VERSION_2
	/*
	 * We are compiling against an 8.3.1- core.  We have to create some
	 * definitions for the new elements as the compiler does not know them
	 * by name.
	 */

	if (channelTypeVersion == TLS_CHANNEL_VERSION_1) {
	    /*
	     * The 'version' element of 8.3.2 is in the the place of the
	     * blockModeProc. For 8.2.0-8.3.1 we have to set our blockModeProc
	     * into this place.
	     */
	    tlsChannelType->blockModeProc = TlsBlockModeProc;
	} else /* channelTypeVersion == TLS_CHANNEL_VERSION_2 */ {
	    /*
	     * For the 8.3.2 core we present ourselves as a version 2
	     * driver. This means a special value in version (ex
	     * blockModeProc), blockModeProc in a different place and of
	     * course usage of the handlerProc.  The last two have to
	     * referenced with pointer magic because they aren't defined
	     * otherwise.
	     */

	    tlsChannelType->blockModeProc =
		(Tcl_DriverBlockModeProc*) TLS_CHANNEL_VERSION_2;
	    (*((Tcl_DriverBlockModeProc**)(&(tlsChannelType->close2Proc)+1)))
		= TlsBlockModeProc;
	    (*((TlsDriverHandlerProc**)(&(tlsChannelType->close2Proc)+3)))
		= TlsNotifyProc;
	}
#else
	/*
	 * Compiled against 8.3.2+. Direct access to all elements possible. Use
	 * channelTypeVersion information to select the values to use.
	 */

	if (channelTypeVersion == TLS_CHANNEL_VERSION_1) {
	    /*
	     * The 'version' element of 8.3.2 is in the the place of the
	     * blockModeProc. For the original patch in 8.1.x and the firstly
	     * included (8.2) we have to set our blockModeProc into this
	     * place.
	     */
	    tlsChannelType->version = (Tcl_ChannelTypeVersion)TlsBlockModeProc;
	} else /* channelTypeVersion == TLS_CHANNEL_VERSION_2 */ {
	    /*
	     * For the 8.3.2 core we present ourselves as a version 2
	     * driver. This means a special value in version (ex
	     * blockModeProc), blockModeProc in a different place and of
	     * course usage of the handlerProc.
	     */

	    tlsChannelType->version       = TCL_CHANNEL_VERSION_2;
	    tlsChannelType->blockModeProc = TlsBlockModeProc;
	    tlsChannelType->handlerProc   = TlsNotifyProc;
	}
#endif
    }
    return tlsChannelType;
}

/*
 *-------------------------------------------------------------------
 *
 * TlsBlockModeProc --
 *