Tls_Free((tls_free_type *) statePtr);
	    return TCL_ERROR;
	}
    }

    statePtr->ctx = ctx;


    /* Preserve channel config */


    Tcl_DStringInit(&upperChannelTranslation);
    Tcl_DStringInit(&upperChannelBlocking);
    Tcl_DStringInit(&upperChannelEOFChar);
    Tcl_DStringInit(&upperChannelEncoding);
    Tcl_GetChannelOption(interp, chan, "-eofchar", &upperChannelEOFChar);
    Tcl_GetChannelOption(interp, chan, "-encoding", &upperChannelEncoding);
    Tcl_GetChannelOption(interp, chan, "-translation", &upperChannelTranslation);
    Tcl_GetChannelOption(interp, chan, "-blocking", &upperChannelBlocking);

    /* Ensure the channel works in binary mode (for the encryption not to get goofed up). */
    Tcl_SetChannelOption(interp, chan, "-translation", "binary");
    Tcl_SetChannelOption(interp, chan, "-blocking", "true");
    
    /* Create stacked channel */
    dprintf("Consuming Tcl channel %s", Tcl_GetChannelName(chan));
    statePtr->self = Tcl_StackChannel(interp, Tls_ChannelType(), (ClientData) statePtr,
	(TCL_READABLE | TCL_WRITABLE), chan);
    dprintf("Created channel named %s", Tcl_GetChannelName(statePtr->self));
    if (statePtr->self == (Tcl_Channel) NULL) {
	/*
	 * No use of Tcl_EventuallyFree because no possible Tcl_Preserve.
	 */
	Tls_Free((tls_free_type *) statePtr);
	Tcl_DStringFree(&upperChannelTranslation);
	Tcl_DStringFree(&upperChannelEncoding);
	Tcl_DStringFree(&upperChannelEOFChar);
	Tcl_DStringFree(&upperChannelBlocking);
	return TCL_ERROR;
    }

    /* Restore channel config */
    Tcl_SetChannelOption(interp, statePtr->self, "-translation", Tcl_DStringValue(&upperChannelTranslation));
    Tcl_SetChannelOption(interp, statePtr->self, "-encoding", Tcl_DStringValue(&upperChannelEncoding));
    Tcl_SetChannelOption(interp, statePtr->self, "-eofchar", Tcl_DStringValue(&upperChannelEOFChar));
    Tcl_SetChannelOption(interp, statePtr->self, "-blocking", Tcl_DStringValue(&upperChannelBlocking));
    Tcl_DStringFree(&upperChannelTranslation);
    Tcl_DStringFree(&upperChannelEncoding);
    Tcl_DStringFree(&upperChannelEOFChar);

	if (request && post_handshake) {
	    SSL_set_post_handshake_auth(statePtr->ssl, 1);
	}

	/* Set client mode */
	SSL_set_connect_state(statePtr->ssl);
    }

    /* Set BIO for read and write operations on SSL object */
    SSL_set_bio(statePtr->ssl, statePtr->p_bio, statePtr->p_bio);
    BIO_set_ssl(statePtr->bio, statePtr->ssl, BIO_NOCLOSE);

    /*
     * End of SSL Init
     */
    dprintf("Returning %s", Tcl_GetChannelName(statePtr->self));

 * Side effects:
 *	May modify the behavior of an IO channel.
 *
 *-------------------------------------------------------------------
 */
static int
UnimportObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) {
    Tcl_Channel chan, parent;	/* The stacked and underlying channels */
    Tcl_DString upperChannelTranslation, upperChannelBlocking, upperChannelEncoding, upperChannelEOFChar;
    int res = TCL_OK;
    (void) clientData;

    dprintf("Called");

    if (objc != 2) {
	Tcl_WrongNumArgs(interp, 1, objv, "channel");
	return TCL_ERROR;
    }

    /* Validate channel name */
    chan = Tcl_GetChannel(interp, Tcl_GetString(objv[1]), NULL);
    if (chan == (Tcl_Channel) NULL) {
	return TCL_ERROR;
    }

    /* Make sure to operate on the topmost channel */
    chan = Tcl_GetTopChannel(chan);
    parent = Tcl_GetStackedChannel(chan);

    /* Verify is a stacked channel */
    if (parent == NULL) {
	Tcl_AppendResult(interp, "bad channel \"", Tcl_GetChannelName(chan),
		"\": not a stacked channel", (char *) NULL);
	    Tcl_SetErrorCode(interp, "TLS", "UNIMPORT", "CHANNEL", "INVALID", (char *) NULL);
	return TCL_ERROR;
    }

    /* Flush any pending data */
    if (Tcl_Flush(chan) != TCL_OK) {
	return TCL_ERROR;
    }

    /* Init storage */
    Tcl_DStringInit(&upperChannelTranslation);
    Tcl_DStringInit(&upperChannelBlocking);
    Tcl_DStringInit(&upperChannelEOFChar);
    Tcl_DStringInit(&upperChannelEncoding);

    /* Preserve current channel config */
    Tcl_GetChannelOption(interp, chan, "-blocking", &upperChannelBlocking);
    Tcl_GetChannelOption(interp, chan, "-encoding", &upperChannelEncoding);
    Tcl_GetChannelOption(interp, chan, "-eofchar", &upperChannelEOFChar);
    Tcl_GetChannelOption(interp, chan, "-translation", &upperChannelTranslation);

    /* Unstack the channel */
    if (Tcl_UnstackChannel(interp, chan) != TCL_OK) {





	res = TCL_ERROR;
    }

    /* Restore channel config */
    Tcl_SetChannelOption(interp, parent, "-encoding", Tcl_DStringValue(&upperChannelEncoding));
    Tcl_SetChannelOption(interp, parent, "-eofchar", Tcl_DStringValue(&upperChannelEOFChar));
    Tcl_SetChannelOption(interp, parent, "-translation", Tcl_DStringValue(&upperChannelTranslation));
    Tcl_SetChannelOption(interp, parent, "-blocking", Tcl_DStringValue(&upperChannelBlocking));

    /* Clean-up */
    Tcl_DStringFree(&upperChannelTranslation);
    Tcl_DStringFree(&upperChannelEncoding);
    Tcl_DStringFree(&upperChannelEOFChar);
    Tcl_DStringFree(&upperChannelBlocking);
    return res;
}

/*
 * Provides Custom BIO layer to interface OpenSSL with TCL. These
 * functions directly interface between the IO channel and BIO buffers.
 *
 * Copyright (C) 1997-2000 Matt Newman <matt@novadigm.com>
 * Copyright (C) 2024 Brian O'Hagan
 *

 */

#include "tlsInt.h"
#include <openssl/bio.h>

/* Define BIO methods structure */
static BIO_METHOD *BioMethods = NULL;


/*
 *-----------------------------------------------------------------------------
 *
 * BioWrite --
 *
 *	This function is used to read encrypted data from the BIO and write it
 *	into the socket. This function will be called in response to the
 *	application calling BIO_write_ex() or BIO_write().
 *
 * Results:
 *	Returns the number of bytes written to channel, 0 for EOF, or
 *	-1 for error.
 *
 * Side effects:
 *	Writes BIO data to channel.
 *
 *-----------------------------------------------------------------------------
 */

static int BioWrite(BIO *bio, const char *buf, int bufLen) {
    Tcl_Channel chan;
    Tcl_Size ret;
    int tclEofChan, tclErrno;

    chan = Tls_GetParent((State *) BIO_get_data(bio), 0);

	    BIO_set_retry_read(bio);
	}
    }
    return (int) ret;
}

/*
 *-----------------------------------------------------------------------------
 *
 * BioRead --
 *
 *	This function is used to read encrypted data from the socket
 *	and write it into the BIO. This function will be called in response to
 *	the application calling BIO_read_ex() or BIO_read().
 *
 * Results:
 *	Returns the number of bytes read from channel, 0 for EOF, or -1 for
 *	error.
 *
 * Side effects:
 *	Reads channel data into BIO.
 *
 *-----------------------------------------------------------------------------
 */

static int BioRead(BIO *bio, char *buf, int bufLen) {
    Tcl_Channel chan;
    Tcl_Size ret = 0;
    int tclEofChan, tclErrno;

    chan = Tls_GetParent((State *) BIO_get_data(bio), 0);

    dprintf("BioRead(%p, <buf>, %d) [%p] returning %" TCL_SIZE_MODIFIER "d", (void *) bio,
	bufLen, (void *) chan, ret);

    return (int) ret;
}

/*
 *-----------------------------------------------------------------------------
 *
 * BioPuts --
 *
 *	This function is used to read a NULL terminated string from the BIO and
 *	write it to the channel. This function will be called in response to
 *	the application calling BIO_puts().
 *
 * Results:
 *	Returns the number of bytes written to channel or 0 for error.
 *
 * Side effects:
 *	Writes data to channel.
 *
 *-----------------------------------------------------------------------------
 */

static int BioPuts(BIO *bio, const char *str) {
    dprintf("BioPuts(%p, <string:%p>) called", bio, str);

    return BioWrite(bio, str, (int) strlen(str));
}

/*
 *-----------------------------------------------------------------------------
 *
 * BioCtrl --
 *
 *	This function is used to process control messages in the BIO. This
 *	function will be called in response to the application calling BIO_ctrl().
 *
 * Results:
 *	Function dependent
 *
 * Side effects:
 *	Function dependent
 *
 *-----------------------------------------------------------------------------
 */

static long BioCtrl(BIO *bio, int cmd, long num, void *ptr) {
    Tcl_Channel chan;
    long ret = 1;

    chan = Tls_GetParent((State *) BIO_get_data(bio), 0);

    dprintf("BioCtrl(%p, 0x%x, 0x%lx, %p)", (void *) bio, cmd, num, ptr);

		dprintf("Got unknown control command (%i)", cmd);
		ret = 0;
		break;
    }
    return ret;
}

/*
 *-----------------------------------------------------------------------------
 *
 * BioNew --
 *
 *	This function is used to create a new instance of the BIO. This
 *	function will be called in response to the application calling BIO_new().
 *
 * Results:
 *	Returns boolean success result (1=success, 0=failure)
 *
 * Side effects:
 *	Initializes BIO structure.
 *
 *-----------------------------------------------------------------------------
 */

static int BioNew(BIO *bio) {
    dprintf("BioNew(%p) called", bio);

    BIO_set_init(bio, 0);
    BIO_set_data(bio, NULL);
    BIO_clear_flags(bio, -1);
    return 1;
}

/*
 *-----------------------------------------------------------------------------
 *
 * BioFree --
 *
 *	This function is used to destroy an instance of a BIO. This function
 *	will be called in response to the application calling BIO_free().
 *
 * Results:
 *	Returns boolean success result
 *
 * Side effects:
 *	Initializes BIO structure.
 *
 *-----------------------------------------------------------------------------
 */

static int BioFree(BIO *bio) {
    if (bio == NULL) {
	return 0;
    }

    dprintf("BioFree(%p) called", bio);

    if (BIO_get_shutdown(bio)) {
	if (BIO_get_init(bio)) {
	    /*shutdown(bio->num, 2) */
	    /*closesocket(bio->num) */
	}

	BIO_set_init(bio, 0);
	BIO_clear_flags(bio, -1);
    }
    return 1;
}

/*
 *-----------------------------------------------------------------------------
 *
 * BIO_new_tcl --
 *
 *	This function is used to initialize the BIO method handlers.
 *
 * Results:
 *	Returns pointer to BIO or NULL for failure
 *
 * Side effects:
 *	Initializes BIO Methods.
 *
 *-----------------------------------------------------------------------------
 */

BIO *BIO_new_tcl(State *statePtr, int flags) {
    BIO *bio;

#ifdef TCLTLS_SSL_USE_FASTPATH
    Tcl_Channel parentChannel;
    const Tcl_ChannelType *parentChannelType;
    void *parentChannelFdIn_p, *parentChannelFdOut_p;
    int parentChannelFdIn, parentChannelFdOut, parentChannelFd;
    int validParentChannelFd;
    int tclGetChannelHandleRet;

    bio = BIO_new(BioMethods);
    BIO_set_data(bio, statePtr);
    BIO_set_shutdown(bio, flags);
    BIO_set_init(bio, 1);
    return bio;
}

/*
 *-----------------------------------------------------------------------------
 *
 * BIO_cleanup --
 *
 *	This function is used to destroy a BIO_METHOD structure and free up any
 *	memory associated with it.
 *
 * Results:
 *	Standard TCL result
 *
 * Side effects:
 *	Destroys BIO Methods.
 *
 *-----------------------------------------------------------------------------
 */

int BIO_cleanup () {
    dprintf("BIO_cleanup() called");

    if (BioMethods != NULL) {
	BIO_meth_free(BioMethods);
	BioMethods = NULL;
    }
    return TCL_OK;
}

/*
 * Provides IO functions to interface between the BIO buffers and TCL
 * applications when using stacked channels.
 *
 * Copyright (C) 1997-2000 Matt Newman <matt@novadigm.com>
 * Copyright (C) 2000 Ajuba Solutions
 * Copyright (C) 2024 Brian O'Hagan
 *
 * 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 (a.kupries@westend.com), 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"
#include <errno.h>

/*
 *-----------------------------------------------------------------------------
 *
 * TlsBlockModeProc --
 *
 *	This procedure is invoked by the generic IO level to set channel to
 *	blocking or nonblocking mode. Called by the generic I/O layer whenever
 *	the Tcl_SetChannelOption() function is used with option -blocking.
 *
 * Results:
 *    0 if successful or POSIX error code if failed.
 *
 * Side effects:
 *    Sets the device into blocking or nonblocking mode.
 *
 *-----------------------------------------------------------------------------
 */
static int TlsBlockModeProc(ClientData instanceData, int mode) {
    State *statePtr = (State *) instanceData;

    if (mode == TCL_MODE_NONBLOCKING) {
	statePtr->flags |= TLS_TCL_ASYNC;
    } else {
	statePtr->flags &= ~(TLS_TCL_ASYNC);
    }
    return 0;
}

/*
 *-----------------------------------------------------------------------------
 *
 * TlsCloseProc --
 *
 *	This procedure is invoked by the generic IO level to perform channel
 *	type specific cleanup when a SSL socket based channel is closed.



 *
 * Results:
 *    0 if successful or POSIX error code if failed.
 *
 * Side effects:
 *    Closes the socket of the channel.
 *
 *-----------------------------------------------------------------------------
 */
static int TlsCloseProc(ClientData instanceData, Tcl_Interp *interp) {
    State *statePtr = (State *) instanceData;

    dprintf("TlsCloseProc(%p)", (void *) statePtr);

    /* Flush any pending data */

    Tls_Clean(statePtr);
    Tcl_EventuallyFree((ClientData)statePtr, Tls_Free);
    return 0;
}

/*
 *-----------------------------------------------------------------------------
 *
 * TlsClose2Proc --
 *
 *	Similar to TlsCloseProc, but allows for separate close read and write
 *	side of channel.
 *
 *-----------------------------------------------------------------------------
 */
static int TlsClose2Proc(ClientData instanceData,    /* The socket state. */
    Tcl_Interp *interp,		/* For errors - can be NULL. */
    int flags)			/* Flags to close read and/or write side of channel */
{
    State *statePtr = (State *) instanceData;

    dprintf("TlsClose2Proc(%p)", (void *) statePtr);

    if ((flags & (TCL_CLOSE_READ|TCL_CLOSE_WRITE)) == 0) {
	return TlsCloseProc(instanceData, interp);
    }
    return EINVAL;
}

/*
 *-----------------------------------------------------------------------------
 *
 * Tls_WaitForConnect --
 *
 *	Perform connect (client) or accept (server) function. Also performs
 *	equivalent of handshake function.
 *
 * Result:
 *    0 if successful, -1 if failed.
 *
 * Side effects:
 *    Issues SSL_accept or SSL_connect
 *
 *-----------------------------------------------------------------------------
 */
int Tls_WaitForConnect(State *statePtr, int *errorCodePtr, int handshakeFailureIsPermanent) {
    unsigned long backingError;
    int err, rc = 0;
    int bioShouldRetry;
    *errorCodePtr = 0;

    dprintf("WaitForConnect(%p)", (void *) statePtr);
    dprintFlags(statePtr);

    /* Can also check SSL_is_init_finished(ssl) */
    if (!(statePtr->flags & TLS_TCL_INIT)) {
	dprintf("Tls_WaitForConnect called on already initialized channel -- returning with immediate success");
	return 0;
    }

    if (statePtr->flags & TLS_TCL_HANDSHAKE_FAILED) {
	/*

	Tls_Error(statePtr, "Wait for failed handshake");
	return -1;
    }

    for (;;) {
	ERR_clear_error();

	/* Not initialized yet! Also calls SSL_do_handshake(). */
	if (statePtr->flags & TLS_TCL_SERVER) {
	    dprintf("Calling SSL_accept()");
	    err = SSL_accept(statePtr->ssl);

	} else {
	    dprintf("Calling SSL_connect()");
	    err = SSL_connect(statePtr->ssl);

    dprintf("Returning in success");
    *errorCodePtr = 0;
    return 0;
}

/*
 *-----------------------------------------------------------------------------
 *
 * TlsInputProc --
 *
 *	This procedure is invoked by the generic IO level to read data from the
 *	BIo. Equivalent to SSL_read.
 *	Called by the generic I/O layer whenever the Tcl_Read(), Tcl_ReadChars,
 *	Tcl_Gets, and Tcl_GetsObj functions are used.
 *
 * Results:
 *	Returns the number of bytes read or -1 on error. Sets errorCodePtr to
 *	a POSIX error code if an error occurred, or 0 if none.
 *
 * Side effects:
 *    Reads input from the input device of the channel.
 *
 *-----------------------------------------------------------------------------
 */
static int TlsInputProc(ClientData instanceData, char *buf, int bufSize, int *errorCodePtr) {
    unsigned long backingError;
    State *statePtr = (State *) instanceData;
    int bytesRead, err;
    *errorCodePtr = 0;

    dprintf("Read(%d)", bufSize);

    /* Skip if user verify callback is still running */
    if (statePtr->flags & TLS_TCL_CALLBACK) {
	dprintf("Callback is running, reading 0 bytes");
	return 0;
    }

     * correctly.  Similar fix in TlsOutputProc. - hobbs
     */
    ERR_clear_error();
    /* BIO_read, where 0 means EOF and -1 means error */
    bytesRead = BIO_read(statePtr->bio, buf, bufSize);
    dprintf("BIO_read -> %d", bytesRead);

    /* Get error is more comprehensive than SSL_want */
    err = SSL_get_error(statePtr->ssl, bytesRead);
    backingError = ERR_get_error();

    if (bytesRead <= 0) {
	if (BIO_should_retry(statePtr->bio)) {
	    dprintf("Read failed with code=%d, bytes read=%d: should retry", err, bytesRead);
	    /* Some docs imply we should redo the BIO_read now */

		*errorCodePtr = Tcl_GetErrno();
		bytesRead = -1;
		Tls_Error(statePtr, ERR_reason_error_string(backingError));
	    }
	    break;

	case SSL_ERROR_ZERO_RETURN:
	    /* Peer has closed the connection by sending the close_notify alert. Can't read, but can write. */
	    dprintf("Got SSL_ERROR_ZERO_RETURN, this means an EOF has been reached");
	    bytesRead = 0;
	    *errorCodePtr = 0;
	    Tls_Error(statePtr, "Peer has closed the connection for writing by sending the close_notify alert");
	    break;

	case SSL_ERROR_WANT_ASYNC:

    }

    dprintf("Input(%d) -> %d [%d]", bufSize, bytesRead, *errorCodePtr);
    return bytesRead;
}

/*
 *-----------------------------------------------------------------------------
 *
 * TlsOutputProc --
 *
 *	This procedure is invoked by the generic IO level to write data to
 *	the BIO. Equivalent to SSL_write. Called by the
 *	generic I/O layer whenever the Tcl_Write(), Tcl_WriteChars,
 *	TTcl_WriteObj functions are used.
 *
 * Results:
 *    Returns the number of bytes written or -1 on error. Sets errorCodePtr
 *    to a POSIX error code if an error occurred, or 0 if none.
 *
 * Side effects:
 *    Writes output on the output device of the channel.
 *
 *-----------------------------------------------------------------------------
 */
static int TlsOutputProc(ClientData instanceData, const char *buf, int toWrite, int *errorCodePtr) {
    unsigned long backingError;
    State *statePtr = (State *) instanceData;
    int written, err;
    *errorCodePtr = 0;

    dprintf("Write(%p, %d)", (void *) statePtr, toWrite);
    dprintBuffer(buf, toWrite);

    /* Skip if user verify callback is still running */
    if (statePtr->flags & TLS_TCL_CALLBACK) {
	dprintf("Don't process output while callbacks are running");
	written = -1;
	*errorCodePtr = EAGAIN;

     * work correctly.  Similar fix in TlsInputProc. - hobbs
     */
    ERR_clear_error();
    /* SSL_write will return 1 for success or 0 for failure */
    written = BIO_write(statePtr->bio, buf, toWrite);
    dprintf("BIO_write(%p, %d) -> [%d]", (void *) statePtr, toWrite, written);

    /* Get error is more comprehensive than SSL_want */
    err = SSL_get_error(statePtr->ssl, written);
    backingError = ERR_get_error();

    if (written <= 0) {
	if (BIO_should_retry(statePtr->bio)) {
	    dprintf("Write failed with code %d, bytes written=%d: should retry", err, written);
	} else {

		*errorCodePtr = Tcl_GetErrno();
		written = -1;
		Tls_Error(statePtr, ERR_reason_error_string(backingError));
	    }
	    break;

	case SSL_ERROR_ZERO_RETURN:
	    /* Peer has closed the connection by sending the close_notify alert. Can't read, but can write. */
	    dprintf("Got SSL_ERROR_ZERO_RETURN, this means an EOF has been reached");
	    written = 0;
	    *errorCodePtr = 0;
	    Tls_Error(statePtr, "Peer has closed the connection for writing by sending the close_notify alert");
	    break;

	case SSL_ERROR_WANT_ASYNC:
	    /* Used with flag SSL_MODE_ASYNC, op didn't complete because an async engine is still processing data */

    }

    dprintf("Output(%d) -> %d", toWrite, written);
    return written;
}

/*
 *-----------------------------------------------------------------------------
 *
 * Tls_GetParent --
 *
 *    Get parent channel for a stacked channel.
 *
 * Results:
 *    Tcl_Channel or NULL if none.
 *
 *-----------------------------------------------------------------------------
 */
Tcl_Channel Tls_GetParent(State *statePtr, int maskFlags) {
    dprintf("Requested to get parent of channel %p", statePtr->self);

    if ((statePtr->flags & ~maskFlags) & TLS_TCL_FASTPATH) {
	dprintf("Asked to get the parent channel while we are using FastPath -- returning NULL");
	return NULL;
    }
    return Tcl_GetStackedChannel(statePtr->self);
}

/*
 *-----------------------------------------------------------------------------
 *
 * TlsSetOptionProc --
 *
 *	Sets an option to value for a SSL socket based channel. Called by the
 *	generic I/O layer whenever the Tcl_SetChannelOption() function is used.
 *
 * Results:
 *    TCL_OK if successful or TCL_ERROR if failed.
 *
 * Side effects:
 *    Updates channel option to new value.
 *
 *-----------------------------------------------------------------------------
 */
static int
TlsSetOptionProc(ClientData instanceData,    /* Socket state. */
    Tcl_Interp *interp,		/* For errors - can be NULL. */
    const char *optionName,	/* Name of the option to set the value for, or
				 * NULL to get all options and their values. */
    const char *optionValue)	/* Value for option. */
{
    State *statePtr = (State *) instanceData;
    Tcl_Channel parent = Tls_GetParent(statePtr, TLS_TCL_FASTPATH);
    Tcl_DriverSetOptionProc *setOptionProc;

    dprintf("Called");

    setOptionProc = Tcl_ChannelSetOptionProc(Tcl_GetChannelType(parent));
    if (setOptionProc != NULL) {
	return (*setOptionProc)(Tcl_GetChannelInstanceData(parent), interp, optionName, optionValue);
    }
    /*
     * Request for a specific option has to fail, we don't have any.
     */
    return Tcl_BadChannelOption(interp, optionName, "");
}

/*
 *-------------------------------------------------------------------
 *
 * TlsGetOptionProc --
 *
 *	Get a option's value for a SSL socket based channel, or a list of all
 *	options and their values. Called by the generic I/O layer whenever the
 *	Tcl_GetChannelOption() function is used.
 *
 *
 * 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. */
    const char *optionName,	/* Name of the option to retrieve the value for, or
				 * NULL to get all options and their values. */
    Tcl_DString *optionValue)	/* Where to store the computed value initialized by caller. */
{
    State *statePtr = (State *) instanceData;
    Tcl_Channel parent = Tls_GetParent(statePtr, TLS_TCL_FASTPATH);
    Tcl_DriverGetOptionProc *getOptionProc;

    dprintf("Called");

    getOptionProc = Tcl_ChannelGetOptionProc(Tcl_GetChannelType(parent));
    if (getOptionProc != NULL) {
	return (*getOptionProc)(Tcl_GetChannelInstanceData(parent), interp, optionName, optionValue);
    } 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_BadChannelOption(interp, optionName, "");
}

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

 *	Called by the notifier via a timer, to flush out data waiting in
 *	channel buffers. called by the generic I/O layer whenever the



 *	Tcl_GetChannelHandle() function is used.
 *
 * Results:
 *        None.
 *
 * Side effects:
 *	Creates notification event.
 *
 *-----------------------------------------------------------------------------
 */
static void TlsChannelHandlerTimer(ClientData clientData) {
    State *statePtr = (State *) clientData;
    int mask = statePtr->want; /* Init to SSL_ERROR_WANT_READ and SSL_ERROR_WANT_WRITE */

    dprintf("Called");

    statePtr->timer = (Tcl_TimerToken) NULL;

    /* Check for amount of data pending in BIO write buffer */
    if (BIO_wpending(statePtr->bio)) {
	dprintf("[chan=%p] BIO writable", statePtr->self);

	mask |= TCL_WRITABLE;
    }

    /* Check for amount of data pending in BIO read buffer */
    if (BIO_pending(statePtr->bio)) {
	dprintf("[chan=%p] BIO readable", statePtr->self);

	mask |= TCL_READABLE;
    }

    /* Notify event subsystem that the channel is readable or writeable */
    dprintf("Notifying ourselves");
    Tcl_NotifyChannel(statePtr->self, mask);
    statePtr->want = 0;

    dprintf("Returning");

    return;
}

/*
 *-----------------------------------------------------------------------------
 *
 * TlsWatchProc --
 *
 *	Set up the event notifier to watch for events of interest from this
 *	channel. Called by the generic I/O layer whenever the user (or the
 *	system) announces its (dis)interest in events on the channel. This is
 *	called repeatedly.
 *
 * Results:
 *    None.
 *
 * Side effects:
 *	Sets up the time-based notifier so that future events on the channel
 *	will be seen by TCL.
 *
 *-----------------------------------------------------------------------------
 */
static void
TlsWatchProc(ClientData instanceData,    /* The socket state. */
    int mask)			/* Events of interest; an OR-ed combination of
				 * TCL_READABLE, TCL_WRITABLE and TCL_EXCEPTION. */
{
    Tcl_Channel     parent;
    State *statePtr = (State *) instanceData;
    Tcl_DriverWatchProc *watchProc;

    dprintf("TlsWatchProc(0x%x)", mask);
    dprintFlags(statePtr);

    /* Pretend to be dead as long as the verify callback is running.
     * Otherwise that callback could be invoked recursively. */
    if (statePtr->flags & TLS_TCL_CALLBACK) {
	dprintf("Callback is on-going, doing nothing");
	return;
    }

    parent = Tls_GetParent(statePtr, TLS_TCL_FASTPATH);

    if (statePtr->flags & TLS_TCL_HANDSHAKE_FAILED) {
	dprintf("Asked to watch a socket with a failed handshake -- nothing can happen here");
	dprintf("Unregistering interest in the lower channel");

	watchProc = Tcl_ChannelWatchProc(Tcl_GetChannelType(parent));
	watchProc(Tcl_GetChannelInstanceData(parent), 0);
	statePtr->watchMask = 0;
	return;
    }

    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.
     */
    dprintf("Registering our interest in the lower channel (chan=%p)", (void *) parent);
    watchProc = Tcl_ChannelWatchProc(Tcl_GetChannelType(parent));
    watchProc(Tcl_GetChannelInstanceData(parent), mask);


    /*
     * Management of the internal timer.
     */
    if (statePtr->timer != (Tcl_TimerToken) NULL) {
	dprintf("A timer was found, deleting it");

	 */
	dprintf("Creating a new timer since data appears to be waiting");
	statePtr->timer = Tcl_CreateTimerHandler(TLS_TCL_DELAY, TlsChannelHandlerTimer, (ClientData) statePtr);
    }
}

/*
 *-----------------------------------------------------------------------------
 *
 * TlsGetHandleProc --
 *
 *	This procedure is invoked by the generic IO level to retrieve an OS
 *	specific handle associated with the channel. Not used for transforms.
 *
 * Results:
 *    The appropriate Tcl_File handle or NULL if none.
 *
 * Side effects:
 *    None.
 *
 *-----------------------------------------------------------------------------
 */
static int TlsGetHandleProc(ClientData instanceData,    /* Socket state. */
    int direction,		/* TCL_READABLE or TCL_WRITABLE */
    ClientData *handlePtr)	/* Handle associated with the channel */
{
    State *statePtr = (State *) instanceData;

    return Tcl_GetChannelHandle(Tls_GetParent(statePtr, TLS_TCL_FASTPATH), direction, handlePtr);
}

/*
 *-----------------------------------------------------------------------------
 *
 * TlsNotifyProc --
 *
 *	This procedure is invoked by the generic IO level to notify the channel
 *	that an event has occurred on the underlying channel. It is used by stacked channel drivers that
 *	wish to be notified of events that occur on the underlying (stacked)
 *	channel.
 *
 * Results:
 *    Type of event or 0 if failed
 *
 * Side effects:
 *    May process the incoming event by itself.
 *
 *-----------------------------------------------------------------------------
 */
static int TlsNotifyProc(ClientData instanceData,    /* Socket state. */
    int mask)			/* type of event that occurred:
				 * OR-ed combination of TCL_READABLE or TCL_WRITABLE */
{
    State *statePtr = (State *) instanceData;
    int errorCode = 0;

    dprintf("Called");

    /*






     * Delete an existing timer. It was not fired, yet we are
     * here, so the channel below generated such an event and we
     * don't have to. The renewal of the interest after the
     * execution of channel handlers will eventually cause us to
     * recreate the timer (in WatchProc).
     */
    if (statePtr->timer != (Tcl_TimerToken) NULL) {
	Tcl_DeleteTimerHandler(statePtr->timer);
	statePtr->timer = (Tcl_TimerToken) NULL;
    }

    /* Skip if user verify callback is still running */
    if (statePtr->flags & TLS_TCL_CALLBACK) {
	dprintf("Callback is on-going, returning failed");

	    dprintf("Tls_WaitForConnect returned an error");
	}
    }

    dprintf("Returning %i", mask);

    /*
     * An event occurred in the underlying channel.  This
     * transformation doesn't process such events thus returns the
     * incoming mask unchanged.
     */
    return mask;
}

/*
 *-----------------------------------------------------------------------------
 *
 * Tls_ChannelType --
 *
 *	Defines the correct TLS channel driver handlers for this channel type.
 *
 * Results:
 *	Tcl_ChannelType structure.
 *
 * Side effects:
 *    None.
 *
 *-----------------------------------------------------------------------------
 */
static const Tcl_ChannelType tlsChannelType = {
    "tls",			/* Type name */
    TCL_CHANNEL_VERSION_5,	/* v5 channel */
    TlsCloseProc,		/* Close proc */
    TlsInputProc,		/* Input proc */
    TlsOutputProc,		/* Output proc */

	int vflags;		/* verify flags */
	SSL *ssl;		/* Struct for SSL processing */
	SSL_CTX *ctx;		/* SSL Context */
	BIO *bio;		/* Struct for SSL processing */
	BIO *p_bio;		/* Parent BIO (that is layered on Tcl_Channel) */


	unsigned int protos_len; /* Length of protos */
	unsigned char *protos;	/* List of supported protocols in protocol format */

	const char *err;
} State;

#ifdef USE_TCL_STUBS
#ifndef Tcl_StackChannel
#error "Unable to compile on this version of Tcl"

Tcl_Obj		*Tls_NewCAObj(Tcl_Interp *interp, const SSL *ssl, int peer);
void            Tls_Error(State *statePtr, const char *msg);
void            Tls_Free(tls_free_type *blockPtr);
void            Tls_Clean(State *statePtr);
int             Tls_WaitForConnect(State *statePtr, int *errorCodePtr, int handshakeFailureIsPermanent);

BIO             *BIO_new_tcl(State* statePtr, int flags);
int		BIO_cleanup();

#define PTR2INT(x) ((int) ((intptr_t) (x)))

#endif /* _TLSINT_H */

#include "tlsInt.h"

/* Define maximum certificate size. Max PEM size 100kB and DER size is 24kB. */
#define CERT_STR_SIZE 24576


/*
 *-----------------------------------------------------------------------------
 *
 * String_to_Hex --
 *
 *	Format contents of a binary string as a hex string
 *
 * Results:
 *	TCL byte array object with x509 identifier as a hex string
 *
 * Side Effects:
 *	None
 *
 *-----------------------------------------------------------------------------
 */
Tcl_Obj *String_to_Hex(unsigned char* input, int ilen) {
    unsigned char *iptr = input;
    Tcl_Obj *resultObj = Tcl_NewByteArrayObj(NULL, 0);
    unsigned char *data = Tcl_SetByteArrayLength(resultObj, ilen*2);
    unsigned char *dptr = &data[0];
    const char *hex = "0123456789abcdef";

    if (resultObj == NULL) {
	return NULL;
    }

    for (int i = 0; i < ilen; i++) {
        *dptr++ = hex[(*iptr>>4)&0xF];
        *dptr++ = hex[(*iptr++)&0xF];
    }
    return resultObj;
}

/*
 *-----------------------------------------------------------------------------
 *
 * BIO_to_Buffer --
 *
 *	Output contents of a BIO to a buffer
 *
 * Results:
 *	Returns length of string in buffer
 *
 * Side effects:
 *	None
 *
 *-----------------------------------------------------------------------------
 */
Tcl_Size BIO_to_Buffer(int result, BIO *bio, void *output, int olen) {
    Tcl_Size len = 0;
    int pending = BIO_pending(bio);

    if (result) {
	len = (Tcl_Size) BIO_read(bio, output, (pending < olen) ? pending : olen);
	(void)BIO_flush(bio);
	if (len < 0) {
	    len = 0;
	}
    }
    return len;
}

/*
 *-----------------------------------------------------------------------------
 *
 * Tls_x509Extensions --
 *
 *	Get list of X.509 Certificate Extensions
 *
 * Results:
 *	TCL list of extensions and boolean critical status
 *
 * Side effects:
 *	None
 *
 *-----------------------------------------------------------------------------
 */
Tcl_Obj *Tls_x509Extensions(Tcl_Interp *interp, X509 *cert) {
    const STACK_OF(X509_EXTENSION) *exts;
    Tcl_Obj *resultObj = Tcl_NewListObj(0, NULL);

    if (resultObj == NULL) {
	return NULL;

	    LAPPEND_BOOL(interp, resultObj, OBJ_nid2ln(OBJ_obj2nid(obj)), critical);
	}
    }
    return resultObj;
}

/*
 *-----------------------------------------------------------------------------
 *
 * Tls_x509Identifier --
 *
 *	Get X.509 certificate Authority or Subject Key Identifiers
 *
 * Results:
 *	TCL byte array object with x509 identifier as a hex string
 *
 * Side effects:
 *	None
 *
 *-----------------------------------------------------------------------------
 */
Tcl_Obj *Tls_x509Identifier(const ASN1_OCTET_STRING *astring) {
    Tcl_Obj *resultObj = NULL;

    if (astring != NULL) {
	resultObj = String_to_Hex((unsigned char *)ASN1_STRING_get0_data(astring),
	    ASN1_STRING_length(astring));
    }
    return resultObj;
}

/*
 *-----------------------------------------------------------------------------
 *
 * Tls_x509KeyUsage --
 *
 *	Get X.509 certificate key usage types
 *
 * Results:
 *	Tcl list of types
 *
 * Side effects:
 *	None
 *
 *-----------------------------------------------------------------------------
 */
Tcl_Obj *Tls_x509KeyUsage(Tcl_Interp *interp, X509 *cert, uint32_t xflags) {
    uint32_t usage = X509_get_key_usage(cert);
    Tcl_Obj *resultObj = Tcl_NewListObj(0, NULL);

    if (resultObj == NULL) {
	return NULL;

    } else {
	    Tcl_ListObjAppendElement(interp, resultObj, Tcl_NewStringObj("unrestricted", -1));
    }
    return resultObj;
}

/*
 *-----------------------------------------------------------------------------
 *
 * Tls_x509Purpose --
 *
 *	Get X.509 certificate purpose
 *
 * Results:
 *	Purpose string
 *
 * Side effects:
 *	None
 *
 *-----------------------------------------------------------------------------
 */
char *Tls_x509Purpose(X509 *cert) {
    char *purpose = NULL;

    if (X509_check_purpose(cert, X509_PURPOSE_SSL_CLIENT, 0) > 0) {
	purpose = "SSL Client";
    } else if (X509_check_purpose(cert, X509_PURPOSE_SSL_SERVER, 0) > 0) {

    } else {
	purpose = "";
    }
    return purpose;
}

/*
 *-----------------------------------------------------------------------------
 *
 * Tls_x509Purposes --
 *
 *	Get X.509 certificate purpose types
 *
 * Results:
 *	Tcl list of each purpose and whether it is CA or non-CA
 *
 * Side effects:
 *	None
 *
 *-----------------------------------------------------------------------------
 */
Tcl_Obj *Tls_x509Purposes(Tcl_Interp *interp, X509 *cert) {
    Tcl_Obj *resultObj = Tcl_NewListObj(0, NULL);
    X509_PURPOSE *ptmp;

    if (resultObj == NULL) {
	return NULL;

	}
	LAPPEND_OBJ(interp, resultObj, X509_PURPOSE_get0_name(ptmp), tmpPtr);
    }
    return resultObj;
}

/*
 *-----------------------------------------------------------------------------
 *
 * Tls_x509Names --
 *
 *	Get a list of Subject Alternate Names (SAN) or Issuer Alternate Names
 *
 * Results:
 *	Tcl list of alternate names
 *
 * Side effects:
 *	None
 *
 *-----------------------------------------------------------------------------
 */
Tcl_Obj *Tls_x509Names(Tcl_Interp *interp, X509 *cert, int nid, BIO *bio) {
    STACK_OF(GENERAL_NAME) *names;
    Tcl_Obj *resultObj = Tcl_NewListObj(0, NULL);
    Tcl_Size len;
    char buffer[1024];

	}
	sk_GENERAL_NAME_pop_free(names, GENERAL_NAME_free);
    }
    return resultObj;
}

/*
 *-----------------------------------------------------------------------------
 *
 * Tls_x509ExtKeyUsage --
 *
 *	Get a list of Extended Key Usages
 *
 * Returns:
 *	Tcl list of usages
 *
 * Side effects:
 *	None
 *
 *-----------------------------------------------------------------------------
 */
Tcl_Obj *Tls_x509ExtKeyUsage(Tcl_Interp *interp, X509 *cert, uint32_t xflags) {
    uint32_t usage = X509_get_key_usage(cert);
    Tcl_Obj *resultObj = Tcl_NewListObj(0, NULL);

    if (resultObj == NULL) {
	return NULL;

    } else {
	    Tcl_ListObjAppendElement(interp, resultObj, Tcl_NewStringObj("unrestricted", -1));
    }
    return resultObj;
}

/*
 *-----------------------------------------------------------------------------
 *
 * Tls_x509CrlDp --
 *
 *	Get list of CRL Distribution Points
 *
 * Returns:
 *	Tcl list of URIs and relative-names
 *
 * Side effects:
 *	None
 *
 *-----------------------------------------------------------------------------
 */
Tcl_Obj *Tls_x509CrlDp(Tcl_Interp *interp, X509 *cert) {
    STACK_OF(DIST_POINT) *crl;
    Tcl_Obj *resultObj = Tcl_NewListObj(0, NULL);

    if (resultObj == NULL) {
	return NULL;

	}
	CRL_DIST_POINTS_free(crl);
    }
    return resultObj;
}

/*
 *-----------------------------------------------------------------------------
 *
 * Tls_x509Oscp
 *
 *	Get list of On-line Certificate Status Protocol (OSCP) URIs
 *
 * Results:
 *	Tcl list of URIs
 *
 * Side effects:
 *	None
 *
 *-----------------------------------------------------------------------------
 */
Tcl_Obj *Tls_x509Oscp(Tcl_Interp *interp, X509 *cert) {
    STACK_OF(OPENSSL_STRING) *ocsp;
    Tcl_Obj *resultObj = Tcl_NewListObj(0, NULL);

    if (resultObj == NULL) {
	return NULL;
    }

    if ((ocsp = X509_get1_ocsp(cert)) != NULL) {
	for (int i = 0; i < sk_OPENSSL_STRING_num(ocsp); i++) {
	    LAPPEND_STR(interp, resultObj, NULL, sk_OPENSSL_STRING_value(ocsp, i), -1);
	}
	X509_email_free(ocsp);
    }
    return resultObj;
}

/*
 *-----------------------------------------------------------------------------
 *
 * Tls_x509CaIssuers --
 *
 *	Get list of Certificate Authority (CA) Issuer URIs
 *
 * Results:
 *	Tcl list of CA issuer URIs
 *
 * Side effects:
 *	None
 *
 *-----------------------------------------------------------------------------
 */
Tcl_Obj *Tls_x509CaIssuers(Tcl_Interp *interp, X509 *cert) {
    STACK_OF(ACCESS_DESCRIPTION) *ads;
    ACCESS_DESCRIPTION *ad;
    Tcl_Obj *resultObj = Tcl_NewListObj(0, NULL);
    unsigned char *buf;

	/* sk_ACCESS_DESCRIPTION_pop_free(ads, ACCESS_DESCRIPTION_free); */
	AUTHORITY_INFO_ACCESS_free(ads);
    }
    return resultObj;
}

/*
 *-----------------------------------------------------------------------------
 *
 * Tls_NewX509Obj --
 *
 *	Parses a X509 certificate and returns contents as a key-value Tcl list.
 *
 * Result:
 *	A Tcl List with the X509 certificate info as a key-value list
 *
 * Side effects:
 *	None
 *
 *-----------------------------------------------------------------------------
 */
Tcl_Obj *Tls_NewX509Obj(Tcl_Interp *interp, X509 *cert, int all) {
    Tcl_Obj *resultObj = Tcl_NewListObj(0, NULL);
    BIO *bio = BIO_new(BIO_s_mem());
    int mdnid, pknid, bits;
    Tcl_Size len;
    unsigned int ulen;