<dt><strong>peername</strong> <em>name</em></dt>
        <dd>The peername from the certificate.</dd>
        <dt><strong>sbits</strong> <em>n</em></dt>
        <dd>The number of bits used for the session key.</dd>
        <dt><strong>cipher</strong> <em>cipher</em></dt>
        <dd>The current cipher in use between the client and
            server channels.</dd>
        <dt><strong>verification<em>result</em></dt>
        <dd>Certificate verification result.</dd>
        <dt><strong>alpn</strong> <em>protocol</em></dt>
        <dd>The protocol selected after Application-Layer Protocol
	    Negotiation (ALPN).</dd>
        <dt><strong>protocol</strong> <em>value</em></dt>
        <dd>The protocol version used for the connection:
	  SSLv2, SSLv3, TLSv1, TLSv1.1, TLSv1.2, TLSv1.3, or unknown</dd>
        <dt><strong>signature_hash</strong> <em>string</em></dt>
        <dd>The signature hash value.</dd>
        <dt><strong>signature_type</strong> <em>type</em></dt>
        <dd>The signature type value.</dd>
        <dt><strong>ca_names</strong> <em>list</em></dt>
        <dd>List of the Certificate Authorities used to create the certificate.</dd>
    </dl>
</blockquote>

    <dt><a name="tls::connection"><strong>tls::connection</strong>
    <em>channel</em></a></dt>
    <dd>Returns the current connection status of an SSL channel. The
        result is a list of key-value pairs describing the

	additional information on the cipher. If <em>supported</em>
	is specified as true, then only the ciphers supported for protocol
	will be listed.</dd>

    <dt><a name="tls::protocols"><strong>tls::protocols</strong></a></dt>
    <dd>Returns a list of supported protocols. Valid values are:
	<b>ssl2</b>, <b>ssl3</b>, <b>tls1</b>, <b>tls1.1</b>, <b>tls1.2</b>,
	and <b>tls1.3</b>. Exact list depends on OpenSSL version and
	compile time flags.</dd>

    <dt><a name="tls::version"><strong>tls::version</strong></a></dt>
    <dd>Returns the OpenSSL version string.</dd>
</dl>

<h3><a name="CALLBACK OPTIONS">CALLBACK OPTIONS</a></h3>

	<dl>

	<dt>
	  <strong>alpn</strong> <em>protocol</em>
	</dt>
	<dd>
	  For servers, this form of callback is invoked when the client ALPN
	  header is received and the first -alpn specified protocol common to
	  the both the client and server is selected. If none, the first
	  client specified protocol is used.
	</dd>

	<br>

<!--	This form of callback is disabled.

	<dt>

	<br>
-->

	<dt>
	  <strong>hello</strong> <em>servername</em>
	</dt>
	<dd>
	  For servers, this form of callback is invoked during client hello
	  message processing.
	</dd>

	<br>

	<dt>
	  <strong>info</strong> <em>channel major minor message</em>
	</dt>

	<br>

	<dt>
	  <strong>sni</strong> <em>servername</em>
	</dt>
	<dd>
	  For servers, this form of callback is invoked when the SNI header
	  from the client is received. Where <i>servername</i> is the client
	  specified servername. This is used when a server supports multiple
	  names, so the right certificate can be used.
	</dd>

	<br>
	<br>

	<dt>
	  <strong>verify</strong> <em>channel depth cert status error</em>
	</dt>
	<dd>
	  This form of callback is invoked by OpenSSL when a new certificate
	  is received from the peer. It allows the client to check the
	  certificate verification result and choose whether to continue or not.
	  <br>
	  The <em>depth</em> argument is an integer representing the
	  current depth on the certificate chain, with
	  <code>0</code> as the subject certificate and higher values
	  denoting progressively more indirect issuer certificates.
	  <br>
	  The <em>cert</em> argument is a list of key-value pairs similar

    X509 *peer;
    Tcl_Obj *objPtr;
    Tcl_Channel chan;
    char *channelName, *ciphers;
    int mode;
    const unsigned char *proto;
    unsigned int len;
    int nid;

    dprintf("Called");

    switch (objc) {
	case 2:
	    channelName = Tcl_GetStringFromObj(objv[1], NULL);
	    break;

    ciphers = (char*)SSL_get_cipher(statePtr->ssl);
    if ((ciphers != NULL) && (strcmp(ciphers, "(NONE)") != 0)) {
	Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj("cipher", -1));
	Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj(SSL_get_cipher(statePtr->ssl), -1));
    }

    /* Verify the X509 certificate presented by the peer */
    Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj("verification", -1));






    Tcl_ListObjAppendElement(interp, objPtr,
	Tcl_NewStringObj(X509_verify_cert_error_string(SSL_get_verify_result(statePtr->ssl)), -1));

    /* Report the selected protocol as a result of the negotiation */
    SSL_get0_alpn_selected(statePtr->ssl, &proto, &len);
    Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj("alpn", -1));
    Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj((char *)proto, (int) len));
    Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj("protocol", -1));
    Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj(SSL_get_version(statePtr->ssl), -1));

    /* Valid for non-RSA signature and TLS 1.3 */
    Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj("signature_hash", -1));
    if (objc == 2 ? SSL_get_peer_signature_nid(statePtr->ssl, &nid) : SSL_get_signature_nid(statePtr->ssl, &nid)) {
	Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj(OBJ_nid2ln(nid), -1));
    } else {
	Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj("", -1));
    }
    Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj("signature_type", -1));
    if (objc == 2 ? SSL_get_peer_signature_type_nid(statePtr->ssl, &nid) : SSL_get_signature_type_nid(statePtr->ssl, &nid)) {
	Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj(OBJ_nid2ln(nid), -1));
    } else {
	Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj("", -1));
    }

    Tcl_SetObjResult(interp, objPtr);
    return TCL_OK;
	clientData = clientData;
}

/*

/*
 * Forward declarations
 */
Tcl_ChannelType *Tls_ChannelType(void);
Tcl_Channel     Tls_GetParent(State *statePtr, int maskFlags);

Tcl_Obj         *Tls_NewX509Obj(Tcl_Interp *interp, X509 *cert);
Tcl_Obj		*Tls_NewCAObj(Tcl_Interp *interp, const SSL *ssl, int peer);
void            Tls_Error(State *statePtr, char *msg);
void            Tls_Free(char *blockPtr);
void            Tls_Clean(State *statePtr);
int             Tls_WaitForConnect(State *statePtr, int *errorCodePtr, int handshakeFailureIsPermanent);

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

/*
 * Copyright (C) 1997-2000 Sensus Consulting Ltd.
 * Matt Newman <matt@sensus.org>
 * Copyright (C) 2023 Brian O'Hagan
 */
#include <tcl.h>
#include <stdio.h>
#include <openssl/bio.h>
#include <openssl/sha.h>
#include <openssl/x509.h>
#include <openssl/x509v3.h>
#include <openssl/asn1.h>
#include "tlsInt.h"

/*
 *  Ensure these are not macros - known to be defined on Win32
 */
#ifdef min