/*
 * TLS Channel - This extension provides a encrypted communication channel
 * using the TLS or SSL protocols. It can be layered on top of any
 * bi-directional Tcl_Channel.
 *
 * This was initially built (almost) from scratch based upon observation of
 * OpenSSL 0.9.2B.
 *
 * Copyright (C) 1997-1999 Matt Newman <[email protected]>
 * some modifications:
 *	Copyright (C) 2000 Ajuba Solutions
 *	Copyright (C) 2002 ActiveState Corporation
 *	Copyright (C) 2004 Starfish Systems
 *	Copyright (C) 2023 Brian O'Hagan
 *
 * TLS (aka SSL) Channel - can be layered on any bi-directional
 * Tcl_Channel (Note: Requires Trf Core Patch)
 *
 * This was built (almost) from scratch based upon observation of
 * OpenSSL 0.9.2B
 *
 * Addition credit is due for Andreas Kupries ([email protected]), for
 * Additional 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"
#include "tclOpts.h"
#include "tlsUuid.h"
#include <stdio.h>
#include <stdlib.h>
#include <openssl/ssl.h>
#include <openssl/crypto.h>
#include <openssl/opensslconf.h>
#include <openssl/rsa.h>
#include <openssl/safestack.h>

/* Min OpenSSL version */
#if OPENSSL_VERSION_NUMBER < 0x10101000L
#error "Only OpenSSL v1.1.1 or later is supported"
#endif


/*
 * Forward declarations
 */

#define F2N(key, dsp) \
	(((key) == NULL) ? (char *)NULL : \
	(((key) == NULL) ? (char *) NULL : \
		Tcl_TranslateFileName(interp, (key), (dsp)))

static SSL_CTX *CTX_Init(State *statePtr, int isServer, int proto, char *key,
		char *certfile, unsigned char *key_asn1, unsigned char *cert_asn1,
		int key_asn1_len, int cert_asn1_len, char *CApath, char *CAfile,
		char *ciphers, char *ciphersuites, int level, char *DHparams);
		Tcl_Size key_asn1_len, Tcl_Size cert_asn1_len, char *CApath, char *CAstore,
		char *CAfile, char *ciphers, char *ciphersuites, int level, char *DHparams);

static int	TlsLibInit(int uninitialize);

#define TLS_PROTO_SSL2		0x01
#define TLS_PROTO_SSL3		0x02
#define TLS_PROTO_TLS1		0x04
#define TLS_PROTO_TLS1_1	0x08
#define TLS_PROTO_TLS1_2	0x10
#define TLS_PROTO_TLS1_3	0x20
#define ENABLED(flag, mask)	(((flag) & (mask)) == (mask))

#define SSLKEYLOGFILE		"SSLKEYLOGFILE"

/*
 * Thread-Safe TLS Code
 */

#ifdef TCL_THREADS
#define OPENSSL_THREAD_DEFINES
#include <openssl/opensslconf.h>

#ifdef OPENSSL_THREADS
#include <openssl/crypto.h>
#include <openssl/ssl.h>

/*
 * Threaded operation requires locking callbacks
 * Based from /crypto/cryptlib.c of OpenSSL and NSOpenSSL.
 */

static Tcl_Mutex *locks = NULL;
static int locksCount = 0;
static Tcl_Mutex init_mx;
#endif /* OPENSSL_THREADS */
#endif /* TCL_THREADS */


/********************/
/* Callbacks        */
/********************/

/*
 *-------------------------------------------------------------------

 */
static int
EvalCallback(Tcl_Interp *interp, State *statePtr, Tcl_Obj *cmdPtr) {
    int code, ok = 0;

    dprintf("Called");

    Tcl_Preserve((void *) interp);
    Tcl_Preserve((void *) statePtr);
    Tcl_Preserve((ClientData) interp);
    Tcl_Preserve((ClientData) statePtr);

    /* Eval callback with success for ok or return value 1, fail for error or return value 0 */
    Tcl_ResetResult(interp);
    code = Tcl_EvalObjEx(interp, cmdPtr, TCL_EVAL_GLOBAL);
    dprintf("EvalCallback: %d", code);
    if (code == TCL_OK) {
	/* Check result for return value */

#if (TCL_MAJOR_VERSION == 8) && (TCL_MINOR_VERSION < 6)
	Tcl_BackgroundError(interp);
#else
	Tcl_BackgroundException(interp, code);
#endif
    }

    Tcl_Release((void *) statePtr);
    Tcl_Release((void *) interp);
    Tcl_Release((ClientData) statePtr);
    Tcl_Release((ClientData) interp);
    return ok;
}

/*
 *-------------------------------------------------------------------
 *
 * InfoCallback --
 *
 *	Monitors SSL connection process
 *
 * Results:
 *	None
 *
 * Side effects:
 *	Calls callback (if defined)
 *
 *-------------------------------------------------------------------
 */
static void
InfoCallback(const SSL *ssl, int where, int ret)
InfoCallback(const SSL *ssl, int where, int ret) {
{
    State *statePtr = (State*)SSL_get_app_data((SSL *)ssl);
    Tcl_Interp *interp	= statePtr->interp;
    Tcl_Obj *cmdPtr;
    const char *major, *minor;

    dprintf("Called");

    if (statePtr->callback == (Tcl_Obj*)NULL)
    if (statePtr->callback == (Tcl_Obj*)NULL) {
	return;
    }

    if (where & SSL_CB_HANDSHAKE_START) {
	major = "handshake";
	minor = "start";
    } else if (where & SSL_CB_HANDSHAKE_DONE) {
	major = "handshake";
	minor = "done";

    char *ver, *type;
    BIO *bio;
    char buffer[15000];
    buffer[0] = 0;

    dprintf("Called");

    if (statePtr->callback == (Tcl_Obj*)NULL)
    if (statePtr->callback == (Tcl_Obj*)NULL) {
	return;
    }

    switch(version) {
#if OPENSSL_VERSION_NUMBER < 0x10100000L && !defined(NO_SSL2) && !defined(OPENSSL_NO_SSL2)
    case SSL2_VERSION:
	ver = "SSLv2";
	break;
#endif

	n = BIO_read(bio, buffer, BIO_pending(bio) < 15000 ? BIO_pending(bio) : 14999);
	n = (n<0) ? 0 : n;
	buffer[n] = 0;
	(void)BIO_flush(bio);
	BIO_free(bio);
   }

    dprintf("Message direction=%d, ver=%s, type=%s, message=%s", write_p, ver, type, &buffer[0]);

    /* Create command to eval with fn, chan, direction, version, type, and message args */
    cmdPtr = Tcl_DuplicateObj(statePtr->callback);
    Tcl_ListObjAppendElement(interp, cmdPtr, Tcl_NewStringObj("message", -1));
    Tcl_ListObjAppendElement(interp, cmdPtr,
	    Tcl_NewStringObj(Tcl_GetChannelName(statePtr->self), -1));
    Tcl_ListObjAppendElement(interp, cmdPtr, Tcl_NewStringObj(write_p ? "Sent" : "Received", -1));
    Tcl_ListObjAppendElement(interp, cmdPtr, Tcl_NewStringObj(ver, -1));

 * Side effects:
 *	The err field of the currently operative State is set
 *	  to a string describing the SSL negotiation failure reason
 *
 *-------------------------------------------------------------------
 */
static int
VerifyCallback(int ok, X509_STORE_CTX *ctx)
VerifyCallback(int ok, X509_STORE_CTX *ctx) {
{
    Tcl_Obj *cmdPtr;
    SSL   *ssl		= (SSL*)X509_STORE_CTX_get_ex_data(ctx, SSL_get_ex_data_X509_STORE_CTX_idx());
    X509  *cert		= X509_STORE_CTX_get_current_cert(ctx);
    State *statePtr	= (State*)SSL_get_app_data(ssl);
    Tcl_Interp *interp	= statePtr->interp;
    int depth		= X509_STORE_CTX_get_error_depth(ctx);
    int err		= X509_STORE_CTX_get_error(ctx);

	} else {
	    return 1;
	}
    } else if (cert == NULL || ssl == NULL) {
	return 0;
    }

    dprintf("VerifyCallback: eval callback");
    dprintf("VerifyCallback: create callback command");

    /* Create command to eval with fn, chan, depth, cert info list, status, and error args */
    cmdPtr = Tcl_DuplicateObj(statePtr->vcmd);
    Tcl_ListObjAppendElement(interp, cmdPtr, Tcl_NewStringObj("verify", -1));
    Tcl_ListObjAppendElement(interp, cmdPtr,
	Tcl_NewStringObj(Tcl_GetChannelName(statePtr->self), -1));
    Tcl_ListObjAppendElement(interp, cmdPtr, Tcl_NewIntObj(depth));
    Tcl_ListObjAppendElement(interp, cmdPtr, Tls_NewX509Obj(interp, cert));
    Tcl_ListObjAppendElement(interp, cmdPtr, Tls_NewX509Obj(interp, cert, 0));
    Tcl_ListObjAppendElement(interp, cmdPtr, Tcl_NewIntObj(ok));
    Tcl_ListObjAppendElement(interp, cmdPtr,
	Tcl_NewStringObj((char*)X509_verify_cert_error_string(err), -1));

    /* Prevent I/O while callback is in progress */
    /* statePtr->flags |= TLS_TCL_CALLBACK; */

    dprintf("VerifyCallback: eval callback");

    /* Eval callback command */
    Tcl_IncrRefCount(cmdPtr);
    ok = EvalCallback(interp, statePtr, cmdPtr);
    Tcl_DecrRefCount(cmdPtr);

    dprintf("VerifyCallback: command result = %d", ok);

void
Tls_Error(State *statePtr, const char *msg) {
    Tcl_Interp *interp	= statePtr->interp;
    Tcl_Obj *cmdPtr, *listPtr;
    unsigned long err;
    statePtr->err = msg;

    dprintf("Called");
    dprintf("Called with message %s", msg);

    if (statePtr->callback == (Tcl_Obj*)NULL)
    if (statePtr->callback == (Tcl_Obj*)NULL) {
	return;
    }

    dprintf("Tls_Error: create callback command");

    /* Create command to eval with fn, chan, and message args */
    cmdPtr = Tcl_DuplicateObj(statePtr->callback);
    Tcl_ListObjAppendElement(interp, cmdPtr, Tcl_NewStringObj("error", -1));
    Tcl_ListObjAppendElement(interp, cmdPtr,
	    Tcl_NewStringObj(Tcl_GetChannelName(statePtr->self), -1));
    if (msg != NULL) {
	Tcl_ListObjAppendElement(interp, cmdPtr, Tcl_NewStringObj(msg, -1));

    } else if ((msg = Tcl_GetString(Tcl_GetObjResult(interp))) != NULL) {
	Tcl_ListObjAppendElement(interp, cmdPtr, Tcl_NewStringObj(msg, -1));

    } else {
	listPtr = Tcl_NewListObj(0, NULL);
	while ((err = ERR_get_error()) != 0) {
	    Tcl_ListObjAppendElement(interp, listPtr, Tcl_NewStringObj(ERR_reason_error_string(err), -1));
	}
	Tcl_ListObjAppendElement(interp, cmdPtr, listPtr);
    }

    dprintf("Tls_Error: eval callback");

    /* Eval callback command */
    Tcl_IncrRefCount(cmdPtr);
    EvalCallback(interp, statePtr, cmdPtr);
    Tcl_DecrRefCount(cmdPtr);
}


	    strncpy(buf, ret, (size_t) len);
	    buf[len] = '\0';
	    return (int) len;
	} else {
	    return -1;
	}
    }

    dprintf("PasswordCallback: create callback command");

    /* Create command to eval with fn, rwflag, and size args */
    cmdPtr = Tcl_DuplicateObj(statePtr->password);
    Tcl_ListObjAppendElement(interp, cmdPtr, Tcl_NewStringObj("password", -1));
    Tcl_ListObjAppendElement(interp, cmdPtr, Tcl_NewIntObj(rwflag));
    Tcl_ListObjAppendElement(interp, cmdPtr, Tcl_NewIntObj(size));

    dprintf("PasswordCallback: eval callback");

    Tcl_Preserve((void *) interp);
    Tcl_Preserve((void *) statePtr);
    Tcl_Preserve((ClientData) interp);
    Tcl_Preserve((ClientData) statePtr);

    /* Eval callback command */
    Tcl_IncrRefCount(cmdPtr);
    code = Tcl_EvalObjEx(interp, cmdPtr, TCL_EVAL_GLOBAL);
    if (code != TCL_OK) {
#if (TCL_MAJOR_VERSION == 8) && (TCL_MINOR_VERSION < 6)
	Tcl_BackgroundError(interp);
#else
	Tcl_BackgroundException(interp, code);
#endif
    }
    Tcl_DecrRefCount(cmdPtr);

    Tcl_Release((void *) statePtr);
    Tcl_Release((ClientData) statePtr);

    /* If successful, pass back password string and truncate if too long */
    if (code == TCL_OK) {
	char *ret = (char *) Tcl_GetStringFromObj(Tcl_GetObjResult(interp), &len);
	if (len > (Tcl_Size) size-1) {
	    len = (Tcl_Size) size-1;
	}
	strncpy(buf, ret, (size_t) len);
	buf[len] = '\0';
	Tcl_Release((void *) interp);
	Tcl_Release((ClientData) interp);
	return (int) len;
    }
    Tcl_Release((void *) interp);
    Tcl_Release((ClientData) interp);
    return -1;
}

/*
 *-------------------------------------------------------------------
 *
 * Session Callback for Clients --

    const unsigned char *p;
    size_t len, remaining;

    dprintf("Called");

    if (statePtr->vcmd == (Tcl_Obj*)NULL) {
	return SSL_CLIENT_HELLO_SUCCESS;
    } else if (ssl == (const SSL *)NULL || arg == NULL) {
    } else if (ssl == (const SSL *)NULL || arg == (void *)NULL) {
	return SSL_CLIENT_HELLO_ERROR;
    }

    /* Get names */
    if (!SSL_client_hello_get0_ext(ssl, TLSEXT_TYPE_server_name, &p, &remaining) || remaining <= 2) {
	*alert = SSL_R_SSLV3_ALERT_ILLEGAL_PARAMETER;
	return SSL_CLIENT_HELLO_ERROR;

 *
 * Side effects:
 *	constructs and destroys SSL context (CTX)
 *
 *-------------------------------------------------------------------
 */
static const char *protocols[] = {
    "ssl2", "ssl3", "tls1", "tls1.1", "tls1.2", "tls1.3", NULL
	"ssl2", "ssl3", "tls1", "tls1.1", "tls1.2", "tls1.3", NULL
};
enum protocol {
    TLS_SSL2, TLS_SSL3, TLS_TLS1, TLS_TLS1_1, TLS_TLS1_2, TLS_TLS1_3, TLS_NONE
};

static int
CiphersObjCmd(
CiphersObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) {
    TCL_UNUSED(void *),
    Tcl_Interp *interp,
    int objc,
    Tcl_Obj	*const objv[])
{
    Tcl_Obj *objPtr = NULL;
    SSL_CTX *ctx = NULL;
    SSL *ssl = NULL;
    STACK_OF(SSL_CIPHER) *sk;
    char buf[BUFSIZ];
    Tcl_Size index;
    int index, verbose = 0, use_supported = 0;
    int verbose = 0, use_supported = 0;
    const SSL_METHOD *method;
    (void) clientData;

    dprintf("Called");

    if ((objc < 2) || (objc > 4)) {
	Tcl_WrongNumArgs(interp, 1, objv, "protocol ?verbose? ?supported?");
	return TCL_ERROR;
    }
    if (Tcl_GetIndexFromObj(interp, objv[1], protocols, "protocol", 0, &index) != TCL_OK) {
	return TCL_ERROR;
    }
    if ((objc > 2) && Tcl_GetBooleanFromObj(interp, objv[2], &verbose) != TCL_OK) {
	return TCL_ERROR;
    }
    if ((objc > 3) && Tcl_GetBooleanFromObj(interp, objv[3], &use_supported) != TCL_OK) {
	return TCL_ERROR;
    }

    ERR_clear_error();

    switch ((enum protocol)index) {
    case TLS_SSL2:
	case TLS_SSL2:
#if OPENSSL_VERSION_NUMBER >= 0x10100000L || defined(NO_SSL2) || defined(OPENSSL_NO_SSL2)
	Tcl_AppendResult(interp, protocols[index], ": protocol not supported", (char *)NULL);
	return TCL_ERROR;
	    Tcl_AppendResult(interp, protocols[index], ": protocol not supported", (char *) NULL);
	    return TCL_ERROR;
#else
	method = SSLv2_method(); break;
	    method = SSLv2_method(); break;
#endif
    case TLS_SSL3:
	case TLS_SSL3:
#if defined(NO_SSL3) || defined(OPENSSL_NO_SSL3) || defined(OPENSSL_NO_SSL3_METHOD)
	Tcl_AppendResult(interp, protocols[index], ": protocol not supported", (char *)NULL);
	return TCL_ERROR;
	    Tcl_AppendResult(interp, protocols[index], ": protocol not supported", (char *) NULL);
	    return TCL_ERROR;
#else
	method = SSLv3_method(); break;
	    method = SSLv3_method(); break;
#endif
    case TLS_TLS1:
	case TLS_TLS1:
#if defined(NO_TLS1) || defined(OPENSSL_NO_TLS1) || defined(OPENSSL_NO_TLS1_METHOD)
	Tcl_AppendResult(interp, protocols[index], ": protocol not supported", (char *)NULL);
	return TCL_ERROR;
	    Tcl_AppendResult(interp, protocols[index], ": protocol not supported", (char *) NULL);
	    return TCL_ERROR;
#else
	method = TLSv1_method(); break;
	    method = TLSv1_method(); break;
#endif
    case TLS_TLS1_1:
	case TLS_TLS1_1:
#if defined(NO_TLS1_1) || defined(OPENSSL_NO_TLS1_1) || defined(OPENSSL_NO_TLS1_1_METHOD)
	Tcl_AppendResult(interp, protocols[index], ": protocol not supported", (char *)NULL);
	return TCL_ERROR;
	    Tcl_AppendResult(interp, protocols[index], ": protocol not supported", (char *) NULL);
	    return TCL_ERROR;
#else
	method = TLSv1_1_method(); break;
	    method = TLSv1_1_method(); break;
#endif
    case TLS_TLS1_2:
	case TLS_TLS1_2:
#if defined(NO_TLS1_2) || defined(OPENSSL_NO_TLS1_2) || defined(OPENSSL_NO_TLS1_2_METHOD)
	Tcl_AppendResult(interp, protocols[index], ": protocol not supported", (char *)NULL);
	return TCL_ERROR;
	    Tcl_AppendResult(interp, protocols[index], ": protocol not supported", (char *) NULL);
	    return TCL_ERROR;
#else
	method = TLSv1_2_method(); break;
	    method = TLSv1_2_method(); break;
#endif
    case TLS_TLS1_3:
	case TLS_TLS1_3:
#if defined(NO_TLS1_3) || defined(OPENSSL_NO_TLS1_3)
	Tcl_AppendResult(interp, protocols[index], ": protocol not supported", (char *)NULL);
	return TCL_ERROR;
	    Tcl_AppendResult(interp, protocols[index], ": protocol not supported", (char *) NULL);
	    return TCL_ERROR;
#else
	method = TLS_method();
	SSL_CTX_set_min_proto_version(ctx, TLS1_3_VERSION);
	SSL_CTX_set_max_proto_version(ctx, TLS1_3_VERSION);
	break;
	    method = TLS_method();
	    SSL_CTX_set_min_proto_version(ctx, TLS1_3_VERSION);
	    SSL_CTX_set_max_proto_version(ctx, TLS1_3_VERSION);
	    break;
#endif
    default:
	method = TLS_method();
	break;
	default:
	    method = TLS_method();
	    break;
    }

    ctx = SSL_CTX_new(method);
    if (ctx == NULL) {
	Tcl_AppendResult(interp, GET_ERR_REASON(), (char *)NULL);
	Tcl_AppendResult(interp, GET_ERR_REASON(), (char *) NULL);
	return TCL_ERROR;
    }

    ssl = SSL_new(ctx);
    if (ssl == NULL) {
	Tcl_AppendResult(interp, GET_ERR_REASON(), (char *)NULL);
	Tcl_AppendResult(interp, GET_ERR_REASON(), (char *) NULL);
	SSL_CTX_free(ctx);
	return TCL_ERROR;
    }

    /* Use list and order as would be sent in a ClientHello or all available ciphers */
    if (use_supported) {
	sk = SSL_get1_supported_ciphers(ssl);

	    for (int i = 0; i < sk_SSL_CIPHER_num(sk); i++) {
		const SSL_CIPHER *c = sk_SSL_CIPHER_value(sk, i);
		if (c == NULL) continue;

		/* cipher name or (NONE) */
		cp = SSL_CIPHER_get_name(c);
		if (cp == NULL) break;
		Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj(cp, -1));
		Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj((char *) cp, -1));
	    }

	} else {
	    objPtr = Tcl_NewStringObj("",0);
	    for (int i = 0; i < sk_SSL_CIPHER_num(sk); i++) {
		const SSL_CIPHER *c = sk_SSL_CIPHER_value(sk, i);
		if (c == NULL) continue;

 *	A standard Tcl result list.
 *
 * Side effects:
 *	none
 *
 *-------------------------------------------------------------------
 */

static int
ProtocolsObjCmd(
ProtocolsObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) {
    TCL_UNUSED(void *),
    Tcl_Interp *interp,
    int objc,
    Tcl_Obj *const objv[]) {
    Tcl_Obj *objPtr;
    (void) clientData;

    dprintf("Called");

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

 *	A standard Tcl result. 1 means handshake complete, 0 means pending.
 *
 * Side effects:
 *	May force SSL negotiation to take place.
 *
 *-------------------------------------------------------------------
 */

static int HandshakeObjCmd(
static int HandshakeObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) {
    TCL_UNUSED(void *),
    Tcl_Interp *interp,
    int objc,
    Tcl_Obj *const objv[])
{
    Tcl_Channel chan;        /* The channel to set a mode on. */
    State *statePtr;        /* client state for ssl socket */
    const char *errStr = NULL;
    int ret = 1;
    int err = 0;
    (void) clientData;

    dprintf("Called");

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

    ERR_clear_error();

    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);
    if (Tcl_GetChannelType(chan) != Tls_ChannelType()) {
	Tcl_AppendResult(interp, "bad channel \"", Tcl_GetChannelName(chan),
		"\": not a TLS channel", (char *)NULL);
	Tcl_SetErrorCode(interp, "TLS", "HANDSHAKE", "CHANNEL", "INVALID", (char *)NULL);
	    "\": not a TLS channel", (char *) NULL);
	Tcl_SetErrorCode(interp, "TLS", "HANDSHAKE", "CHANNEL", "INVALID", (char *) NULL);
	return TCL_ERROR;
    }
    statePtr = (State *)Tcl_GetChannelInstanceData(chan);

    dprintf("Calling Tls_WaitForConnect");
    ret = Tls_WaitForConnect(statePtr, &err, 1);
    dprintf("Tls_WaitForConnect returned: %i", ret);

	Tcl_ResetResult(interp);
	Tcl_SetErrno(err);

	if (!errStr || (*errStr == 0)) {
	    errStr = Tcl_PosixError(interp);
	}

	Tcl_AppendResult(interp, "handshake failed: ", errStr, (char *)NULL);
	Tcl_AppendResult(interp, "handshake failed: ", errStr, (char *) NULL);
	if ((result = SSL_get_verify_result(statePtr->ssl)) != X509_V_OK) {
	    Tcl_AppendResult(interp, " due to \"", X509_verify_cert_error_string(result), "\"", (char *)NULL);
	    Tcl_AppendResult(interp, " due to \"", X509_verify_cert_error_string(result), "\"", (char *) NULL);
	}
	Tcl_SetErrorCode(interp, "TLS", "HANDSHAKE", "FAILED", (char *)NULL);
	Tcl_SetErrorCode(interp, "TLS", "HANDSHAKE", "FAILED", (char *) NULL);
	dprintf("Returning TCL_ERROR with handshake failed: %s", errStr);
	return TCL_ERROR;
    } else {
	if (err != 0) {
	    dprintf("Got an error with a completed handshake: err = %i", err);
	}
	ret = 1;
    }

    dprintf("Returning TCL_OK with data \"%i\"", ret);
    Tcl_SetObjResult(interp, Tcl_NewIntObj(ret));
    return TCL_OK;
}


/*
 *-------------------------------------------------------------------
 *
 * ImportObjCmd --
 *
 *	This procedure is invoked to process the "ssl" command
 *
 *	The ssl command pushes SSL over a (newly connected) tcp socket
 *
 * Results:
 *	A standard Tcl result.
 *
 * Side effects:
 *	May modify the behavior of an IO channel.
 *
 *-------------------------------------------------------------------
 */

static int
ImportObjCmd(
    TCL_UNUSED(void *),
    Tcl_Interp *interp,
    int objc,
    Tcl_Obj *const objv[])
ImportObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) {
{
    Tcl_Channel chan;		/* The channel to set a mode on. */
    State *statePtr;		/* client state for ssl socket */
    SSL_CTX *ctx		= NULL;
    Tcl_Obj *script		= NULL;
    Tcl_Obj *password		= NULL;
    Tcl_Obj *vcmd		= NULL;
    Tcl_DString upperChannelTranslation, upperChannelBlocking, upperChannelEncoding, upperChannelEOFChar;

    Tcl_Size key_len		= 0;
    unsigned char *cert		= NULL;
    Tcl_Size cert_len		= 0;
    char *ciphers		= NULL;
    char *ciphersuites		= NULL;
    char *CAfile		= NULL;
    char *CApath		= NULL;
    char *CAstore		= NULL;
    char *DHparams		= NULL;
    char *model			= NULL;
    char *servername		= NULL;	/* hostname for Server Name Indication */
    char *session_id		= NULL;
    Tcl_Obj *alpn		= NULL;
    int ssl2 = 0, ssl3 = 0;
    int tls1 = 1, tls1_1 = 1, tls1_2 = 1, tls1_3 = 1;
    int proto = 0, level = -1;
    int verify = 0, require = 0, request = 1, post_handshake = 0;
    (void) clientData;

    dprintf("Called");

#if defined(NO_TLS1) || defined(OPENSSL_NO_TLS1)
    tls1 = 0;
#endif
#if defined(NO_TLS1_1) || defined(OPENSSL_NO_TLS1_1)

	if (opt[0] != '-')
	    break;

	OPTOBJ("-alpn", alpn);
	OPTSTR("-cadir", CApath);
	OPTSTR("-cafile", CAfile);
	OPTSTR("-castore", CAstore);
	OPTBYTE("-cert", cert, cert_len);
	OPTSTR("-certfile", certfile);
	OPTSTR("-cipher", ciphers);
	OPTSTR("-ciphers", ciphers);
	OPTSTR("-ciphersuites", ciphersuites);
	OPTOBJ("-command", script);
	OPTSTR("-dhparams", DHparams);

	OPTBOOL("-tls1", tls1);
	OPTBOOL("-tls1.1", tls1_1);
	OPTBOOL("-tls1.2", tls1_2);
	OPTBOOL("-tls1.3", tls1_3);
	OPTOBJ("-validatecommand", vcmd);
	OPTOBJ("-vcmd", vcmd);

	OPTBAD("option", "-alpn, -cadir, -cafile, -cert, -certfile, -cipher, -ciphersuites, -command, -dhparams, -key, -keyfile, -model, -password, -post_handshake, -request, -require, -security_level, -server, -servername, -session_id, -ssl2, -ssl3, -tls1, -tls1.1, -tls1.2, -tls1.3, or -validatecommand");
	OPTBAD("option", "-alpn, -cadir, -cafile, -castore, -cert, -certfile, -cipher, -ciphersuites, -command, -dhparams, -key, -keyfile, -model, -password, -post_handshake, -request, -require, -security_level, -server, -servername, -session_id, -ssl2, -ssl3, -tls1, -tls1.1, -tls1.2, -tls1.3, or -validatecommand");

	return TCL_ERROR;
    }
    if (request)	    verify |= SSL_VERIFY_CLIENT_ONCE | SSL_VERIFY_PEER;
    if (request && require) verify |= SSL_VERIFY_FAIL_IF_NO_PEER_CERT;
    if (request)		verify |= SSL_VERIFY_CLIENT_ONCE | SSL_VERIFY_PEER;
    if (request && require)	verify |= SSL_VERIFY_FAIL_IF_NO_PEER_CERT;
    if (request && post_handshake)	verify |= SSL_VERIFY_POST_HANDSHAKE;
    if (verify == 0)	verify = SSL_VERIFY_NONE;
    if (verify == 0)		verify = SSL_VERIFY_NONE;

    proto |= (ssl2 ? TLS_PROTO_SSL2 : 0);
    proto |= (ssl3 ? TLS_PROTO_SSL3 : 0);
    proto |= (tls1 ? TLS_PROTO_TLS1 : 0);
    proto |= (tls1_1 ? TLS_PROTO_TLS1_1 : 0);
    proto |= (tls1_2 ? TLS_PROTO_TLS1_2 : 0);
    proto |= (tls1_3 ? TLS_PROTO_TLS1_3 : 0);

    /* reset to NULL if blank string provided */
    if (cert && !*cert)		        cert	        = NULL;
    if (key && !*key)		        key	        = NULL;
    if (certfile && !*certfile)         certfile	= NULL;
    if (keyfile && !*keyfile)		keyfile	        = NULL;
    if (ciphers && !*ciphers)	        ciphers	        = NULL;
    if (ciphersuites && !*ciphersuites) ciphersuites    = NULL;
    if (CAfile && !*CAfile)	        CAfile	        = NULL;
    if (CApath && !*CApath)	        CApath	        = NULL;
    if (CAstore && !*CAstore)	        CAstore	        = NULL;
    if (DHparams && !*DHparams)	        DHparams        = NULL;

    /* new SSL state */
    statePtr		= (State *) ckalloc((unsigned) sizeof(State));
    memset(statePtr, 0, sizeof(State));

    statePtr->flags	= flags;
    statePtr->interp	= interp;
    statePtr->want	= 0;
    statePtr->vflags	= verify;
    statePtr->err	= "";

    /* allocate script */
    if (script) {
	(void) Tcl_GetStringFromObj(script, &len);
	if (len) {

    }

    if (model != NULL) {
	int mode;
	/* Get the "model" context */
	chan = Tcl_GetChannel(interp, model, &mode);
	if (chan == (Tcl_Channel) NULL) {
	    Tls_Free(statePtr);
	    Tls_Free((tls_free_type *) statePtr);
	    return TCL_ERROR;
	}

	/*
	 * Make sure to operate on the topmost channel
	 */
	chan = Tcl_GetTopChannel(chan);
	if (Tcl_GetChannelType(chan) != Tls_ChannelType()) {
	    Tcl_AppendResult(interp, "bad channel \"", Tcl_GetChannelName(chan),
		    "\": not a TLS channel", (char *)NULL);
	    Tcl_SetErrorCode(interp, "TLS", "IMPORT", "CHANNEL", "INVALID", (char *)NULL);
	    Tls_Free(statePtr);
		"\": not a TLS channel", (char *) NULL);
	    Tcl_SetErrorCode(interp, "TLS", "IMPORT", "CHANNEL", "INVALID", (char *) NULL);
	    Tls_Free((tls_free_type *) statePtr);
	    return TCL_ERROR;
	}
	ctx = ((State *)Tcl_GetChannelInstanceData(chan))->ctx;
    } else {
	if ((ctx = CTX_Init(statePtr, server, proto, keyfile, certfile, key, cert, (int)key_len,
		(int)cert_len, CApath, CAfile, ciphers, ciphersuites, level, DHparams)) == NULL) {
	    Tls_Free(statePtr);
	if ((ctx = CTX_Init(statePtr, server, proto, keyfile, certfile, key, cert, key_len,
	    cert_len, CApath, CAstore, CAfile, ciphers, ciphersuites, level, DHparams)) == NULL) {
	    Tls_Free((tls_free_type *) statePtr);
	    return TCL_ERROR;
	}
    }

    statePtr->ctx = ctx;

    /*
     * We need to make sure that the channel works in binary (for the
     * encryption not to get goofed up).
     * We only want to adjust the buffering in pre-v2 channels, where
     * each channel in the stack maintained its own buffers.
    /* 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(), statePtr, (TCL_READABLE | TCL_WRITABLE), 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(statePtr);
	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);
    Tcl_DStringFree(&upperChannelBlocking);

    /*
     * SSL Initialization
     */
    statePtr->ssl = SSL_new(statePtr->ctx);
    if (!statePtr->ssl) {
	/* SSL library error */
	Tcl_AppendResult(interp, "couldn't construct ssl session: ", GET_ERR_REASON(), (char *)NULL);
	Tcl_SetErrorCode(interp, "TLS", "IMPORT", "INIT", "FAILED", (char *)NULL);
	Tls_Free(statePtr);
	Tcl_AppendResult(interp, "couldn't construct ssl session: ", GET_ERR_REASON(), (char *) NULL);
	    Tcl_SetErrorCode(interp, "TLS", "IMPORT", "INIT", "FAILED", (char *) NULL);
	Tls_Free((tls_free_type *) statePtr);
	return TCL_ERROR;
    }

    /* Set host server name */
    if (servername) {
	/* Sets the server name indication (SNI) in ClientHello extension */
	/* Per RFC 6066, hostname is a ASCII encoded string, though RFC 4366 says UTF-8. */
	if (!SSL_set_tlsext_host_name(statePtr->ssl, servername) && require) {
	    Tcl_AppendResult(interp, "Set SNI extension failed: ", GET_ERR_REASON(), (char *)NULL);
	    Tcl_SetErrorCode(interp, "TLS", "IMPORT", "SNI", "FAILED", (char *)NULL);
	    Tls_Free(statePtr);
	    Tcl_AppendResult(interp, "Set SNI extension failed: ", GET_ERR_REASON(), (char *) NULL);
	    Tcl_SetErrorCode(interp, "TLS", "IMPORT", "SNI", "FAILED", (char *) NULL);
	    Tls_Free((tls_free_type *) statePtr);
	    return TCL_ERROR;
	}

	/* Set hostname for peer certificate hostname verification in clients.
	   Don't use SSL_set1_host since it has limitations. */
	if (!SSL_add1_host(statePtr->ssl, servername)) {
	    Tcl_AppendResult(interp, "Set DNS hostname failed: ", GET_ERR_REASON(), (char *)NULL);
	    Tcl_SetErrorCode(interp, "TLS", "IMPORT", "HOSTNAME", "FAILED", (char *)NULL);
	    Tls_Free(statePtr);
	    Tcl_AppendResult(interp, "Set DNS hostname failed: ", GET_ERR_REASON(), (char *) NULL);
	    Tcl_SetErrorCode(interp, "TLS", "IMPORT", "HOSTNAME", "FAILED", (char *) NULL);
	    Tls_Free((tls_free_type *) statePtr);
	    return TCL_ERROR;
	}
    }

    /* Resume session id */
    if (session_id && strlen(session_id) <= SSL_MAX_SID_CTX_LENGTH) {
	/* SSL_set_session() */
	if (!SSL_SESSION_set1_id_context(SSL_get_session(statePtr->ssl),
		(const unsigned char *) session_id, (unsigned int) strlen(session_id))) {
	    Tcl_AppendResult(interp, "Resume session failed: ", GET_ERR_REASON(), (char *)NULL);
	    Tcl_SetErrorCode(interp, "TLS", "IMPORT", "SESSION", "FAILED", (char *)NULL);
	    Tls_Free(statePtr);
	    Tcl_AppendResult(interp, "Resume session failed: ", GET_ERR_REASON(), (char *) NULL);
	    Tcl_SetErrorCode(interp, "TLS", "IMPORT", "SESSION", "FAILED", (char *) NULL);
	    Tls_Free((tls_free_type *) statePtr);
	    return TCL_ERROR;
	}
    }

    /* Enable Application-Layer Protocol Negotiation. Examples are: http/1.0,
	http/1.1, h2, h3, ftp, imap, pop3, xmpp-client, xmpp-server, mqtt, irc, etc. */
    if (alpn) {
	/* Convert a TCL list into a protocol-list in wire-format */
	unsigned char *protos, *p;
	unsigned int protos_len = 0;
	Tcl_Size cnt, i;
	int j;
	Tcl_Obj **list;

	if (Tcl_ListObjGetElements(interp, alpn, &cnt, &list) != TCL_OK) {
	    Tls_Free(statePtr);
	    Tls_Free((tls_free_type *) statePtr);
	    return TCL_ERROR;
	}

	/* Determine the memory required for the protocol-list */
	for (i = 0; i < cnt; i++) {
	    Tcl_GetStringFromObj(list[i], &len);
	    if (len > 255) {
		Tcl_AppendResult(interp, "ALPN protocol names too long", (char *)NULL);
		Tcl_SetErrorCode(interp, "TLS", "IMPORT", "ALPN", "FAILED", (char *)NULL);
		Tls_Free(statePtr);
		Tcl_AppendResult(interp, "ALPN protocol names too long", (char *) NULL);
		Tcl_SetErrorCode(interp, "TLS", "IMPORT", "ALPN", "FAILED", (char *) NULL);
		Tls_Free((tls_free_type *) statePtr);
		return TCL_ERROR;
	    }
	    protos_len += 1 + (int) len;
	}

	/* Build the complete protocol-list */
	protos = ckalloc(protos_len);
	/* protocol-lists consist of 8-bit length-prefixed, byte strings */
	for (j = 0, p = protos; j < cnt; j++) {
	    char *str = Tcl_GetStringFromObj(list[j], &len);
	    *p++ = (unsigned char) len;
	    memcpy(p, str, (size_t) len);
	    p += len;
	}

	/* SSL_set_alpn_protos makes a copy of the protocol-list */
	/* Note: This function reverses the return value convention */
	if (SSL_set_alpn_protos(statePtr->ssl, protos, protos_len)) {
	    Tcl_AppendResult(interp, "Set ALPN protocols failed: ", GET_ERR_REASON(), (char *)NULL);
	    Tcl_SetErrorCode(interp, "TLS", "IMPORT", "ALPN", "FAILED", (char *)NULL);
	    Tls_Free(statePtr);
	    Tcl_AppendResult(interp, "Set ALPN protocols failed: ", GET_ERR_REASON(), (char *) NULL);
	    Tcl_SetErrorCode(interp, "TLS", "IMPORT", "ALPN", "FAILED", (char *) NULL);
	    Tls_Free((tls_free_type *) statePtr);
	    ckfree(protos);
	    return TCL_ERROR;
	}

	/* Store protocols list */
	statePtr->protos = protos;
	statePtr->protos_len = protos_len;
    } else {
	statePtr->protos = NULL;
	statePtr->protos_len = 0;
    }

    /*
     * SSL Callbacks
     */
    SSL_set_app_data(statePtr->ssl, (void *)statePtr);	/* point back to us */
    SSL_set_verify(statePtr->ssl, verify, VerifyCallback);
    /*SSL_set_verify_depth(SSL_set_verify_depth, 0);*/
    SSL_set_info_callback(statePtr->ssl, InfoCallback);

    /* Callback for observing protocol messages */
#ifndef OPENSSL_NO_SSL_TRACE
    /* void SSL_CTX_set_msg_callback_arg(statePtr->ctx, (void *)statePtr);
    void SSL_CTX_set_msg_callback(statePtr->ctx, MessageCallback); */
    SSL_set_msg_callback_arg(statePtr->ssl, (void *)statePtr);

	/* Enable server to send cert request after handshake (TLS 1.3 only) */
	/* A write operation must take place for the Certificate Request to be
	   sent to the client, this can be done with SSL_do_handshake(). */
	if (request && post_handshake && tls1_3) {
	    SSL_verify_client_post_handshake(statePtr->ssl);
	}

	/* set automatic curve selection */
	SSL_set_ecdh_auto(statePtr->ssl, 1);

	/* Set server mode */
	statePtr->flags |= TLS_TCL_SERVER;
	SSL_set_accept_state(statePtr->ssl);
    } else {
	/* Client callbacks */
#ifdef USE_NPN
	if (statePtr->protos != NULL && tls1_2 == 0 && tls1_3 == 0) {

	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);
    BIO_set_ssl_mode(statePtr->bio, (long) !server);

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

    return TCL_OK;
}

/*
 *-------------------------------------------------------------------
 *
 * UnimportObjCmd --
 *
 *	This procedure is invoked to remove the topmost channel filter.
 *
 * Results:
 *	A standard Tcl result.
 *
 * Side effects:
 *	May modify the behavior of an IO channel.
 *
 *-------------------------------------------------------------------
 */

static int
UnimportObjCmd(
    TCL_UNUSED(void *),
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;
    Tcl_Interp *interp,
    int objc,
    Tcl_Obj *const objv[])
    int res = TCL_OK;
    (void) clientData;
{
    Tcl_Channel chan;		/* The channel to set a mode on. */

    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);

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

    /* Flush any pending data */
    if (Tcl_OutputBuffered(chan) > 0 && Tcl_Flush(chan) != TCL_OK) {
	Tcl_AppendResult(interp, "can't flush channel", (char *) NULL);
	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_ERROR) {
	return TCL_ERROR;
    }

    return TCL_OK;
    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;
}

/*
 *-------------------------------------------------------------------
 *
 * TlsLoadClientCAFileFromMemory -- Load certificates from a client
 *	CA file from VFS into memory.
 *
 * Results:
 *	Number of certificates loaded or 0 for none.
 *
 * Side effects:
 *	Loads CA certificates
 *
 *-------------------------------------------------------------------
 */
static int
TlsLoadClientCAFileFromMemory(Tcl_Interp *interp, SSL_CTX *ctx, Tcl_Obj *file) {
    BIO  *bio  = NULL;
    X509 *cert = NULL;
    X509_STORE *store = NULL;
    Tcl_Obj    *buf = NULL;
    const void *data = NULL;
    X509_NAME  *name = NULL;
    STACK_OF(X509_NAME) *certNames = NULL;
    int ret = 0;
    Tcl_Size len = 0;

    /* Read file into memory */
    Tcl_Channel in = Tcl_FSOpenFileChannel(interp, file, "r", 0);
    if (in == NULL) {
	goto cleanup;
    }
    Tcl_SetChannelOption(interp, in, "-encoding", "binary");
    buf = Tcl_NewObj();
    Tcl_IncrRefCount(buf);

    if (Tcl_ReadChars(in, buf, -1, 0) < 0) {
	Tcl_Close(interp, in);
	goto cleanup;
    }
    Tcl_Close(interp, in);

    data = (const void *) Tcl_GetByteArrayFromObj(buf, &len);
    bio = BIO_new_mem_buf(data, len);
    if (bio == NULL) {
	goto cleanup;
    }

    /* Where the certs go */
    store = SSL_CTX_get_cert_store(ctx);
    if (store == NULL) {
	store = X509_STORE_new();
	if (store == NULL) {
	    goto cleanup;
	}
    }

    /* Where the CA names go */
    certNames = sk_X509_NAME_new_null();
    if (!certNames) {
        goto cleanup;
    }

    /* Attempt to load all certs from the PEM file */
    while ((cert = PEM_read_bio_X509(bio, NULL, 0, NULL)) != NULL) {
        if (X509_STORE_add_cert(store, cert) == 0) {
            X509_free(cert);
            ret = 0;
            goto cleanup;
        }
        /* Copy name to stack before certificate gets freed */
	name = X509_get_subject_name(cert);
        if (name) {
            X509_NAME *name_copy = X509_NAME_dup(name);
            if (!name_copy || !sk_X509_NAME_push(certNames, name_copy)) {
                X509_free(cert);
		ret = 0;
                goto cleanup;
            }
        }
        X509_free(cert);
        ret ++;
    }

    /* At least one cert was added so retain the store and CA list */
    if (ret) {
	if (SSL_CTX_get_cert_store(ctx) == NULL) {
	    SSL_CTX_set_cert_store(ctx, store);
	}
	SSL_CTX_set_client_CA_list(ctx, certNames);
    }

  cleanup:

    if (! ret) {
	/* New store is not required */
	if (store != SSL_CTX_get_cert_store(ctx)) {
	    X509_STORE_free(store);
	}
	/* Cert names will not be used */
	if (certNames) {
	    sk_X509_NAME_pop_free(certNames, X509_NAME_free);
	}
    }

    BIO_free(bio);

    if (buf)
	Tcl_DecrRefCount(buf);

    return ret;
}

/*
 *-------------------------------------------------------------------
 *
 * CTX_Init -- construct a SSL_CTX instance
 *
 * Results:
 *	A valid SSL_CTX instance or NULL.
 *
 * Side effects:
 *	constructs SSL context (CTX)
 *
 *-------------------------------------------------------------------
 */

static SSL_CTX *
CTX_Init(
    State *statePtr,
CTX_Init(State *statePtr, int isServer, int proto, char *keyfile, char *certfile,
    int isServer,
    int proto,
    char *keyfile,
    char *certfile,
    unsigned char *key,
    unsigned char *key, unsigned char *cert, Tcl_Size key_len, Tcl_Size cert_len, char *CApath,
    unsigned char *cert,
    int key_len,
    int cert_len,
    char *CApath,
    char *CAfile,
    char *ciphers,
    char *CAstore, char *CAfile, char *ciphers, char *ciphersuites, int level, char *DHparams) {
    char *ciphersuites,
    int level,
    char *DHparams)
{
    Tcl_Interp *interp = statePtr->interp;
    SSL_CTX *ctx = NULL;
    Tcl_DString ds;
    int off = 0, abort = 0;
    int load_private_key;
    const SSL_METHOD *method;

    dprintf("Called");

    if (!proto) {
	Tcl_AppendResult(interp, "no valid protocol selected", (char *)NULL);
	Tcl_AppendResult(interp, "no valid protocol selected", (char *) NULL);
	return NULL;
    }

    /* create SSL context */
#if OPENSSL_VERSION_NUMBER >= 0x10100000L || defined(NO_SSL2) || defined(OPENSSL_NO_SSL2)
    if (ENABLED(proto, TLS_PROTO_SSL2)) {
	Tcl_AppendResult(interp, "SSL2 protocol not supported", (char *)NULL);
	Tcl_AppendResult(interp, "SSL2 protocol not supported", (char *) NULL);
	return NULL;
    }
#endif
#if defined(NO_SSL3) || defined(OPENSSL_NO_SSL3)
    if (ENABLED(proto, TLS_PROTO_SSL3)) {
	Tcl_AppendResult(interp, "SSL3 protocol not supported", (char *)NULL);
	Tcl_AppendResult(interp, "SSL3 protocol not supported", (char *) NULL);
	return NULL;
    }
#endif
#if defined(NO_TLS1) || defined(OPENSSL_NO_TLS1)
    if (ENABLED(proto, TLS_PROTO_TLS1)) {
	Tcl_AppendResult(interp, "TLS 1.0 protocol not supported", (char *)NULL);
	Tcl_AppendResult(interp, "TLS 1.0 protocol not supported", (char *) NULL);
	return NULL;
    }
#endif
#if defined(NO_TLS1_1) || defined(OPENSSL_NO_TLS1_1)
    if (ENABLED(proto, TLS_PROTO_TLS1_1)) {
	Tcl_AppendResult(interp, "TLS 1.1 protocol not supported", (char *)NULL);
	Tcl_AppendResult(interp, "TLS 1.1 protocol not supported", (char *) NULL);
	return NULL;
    }
#endif
#if defined(NO_TLS1_2) || defined(OPENSSL_NO_TLS1_2)
    if (ENABLED(proto, TLS_PROTO_TLS1_2)) {
	Tcl_AppendResult(interp, "TLS 1.2 protocol not supported", (char *)NULL);
	Tcl_AppendResult(interp, "TLS 1.2 protocol not supported", (char *) NULL);
	return NULL;
    }
#endif
#if defined(NO_TLS1_3) || defined(OPENSSL_NO_TLS1_3)
    if (ENABLED(proto, TLS_PROTO_TLS1_3)) {
	Tcl_AppendResult(interp, "TLS 1.3 protocol not supported", (char *)NULL);
	Tcl_AppendResult(interp, "TLS 1.3 protocol not supported", (char *) NULL);
	return NULL;
    }
#endif
    if (proto == 0) {
	/* Use full range */
	SSL_CTX_set_min_proto_version(ctx, 0);
	SSL_CTX_set_max_proto_version(ctx, 0);

	SSL_CTX_set_options(ctx, SSL_OP_CIPHER_SERVER_PREFERENCE);
    }

#if OPENSSL_VERSION_NUMBER < 0x10100000L
    OpenSSL_add_all_algorithms(); /* Load ciphers and digests */
#endif

    SSL_CTX_set_app_data(ctx, interp);	/* remember the interpreter */
    SSL_CTX_set_options(ctx, SSL_OP_ALL);	/* all SSL bug workarounds */
    SSL_CTX_set_options(ctx, SSL_OP_NO_COMPRESSION);	/* disable compression even if supported */
    SSL_CTX_set_options(ctx, off);		/* disable protocol versions */
#if OPENSSL_VERSION_NUMBER < 0x10101000L
    SSL_CTX_set_mode(ctx, SSL_MODE_AUTO_RETRY);	/* handle new handshakes in background. On by default in OpenSSL 1.1.1. */
#endif
    SSL_CTX_set_app_data(ctx, (void*)interp);	/* remember the interpreter */
    SSL_CTX_set_options(ctx, SSL_OP_ALL);	/* Enable all SSL bug workarounds */
    SSL_CTX_set_options(ctx, SSL_OP_NO_COMPRESSION);	/* Disable compression even if supported */
    SSL_CTX_set_options(ctx, off);		/* Disable specified protocol versions */

    /* Allow writes to report success when less than all records have been written */
    SSL_CTX_set_mode(ctx, SSL_MODE_ENABLE_PARTIAL_WRITE);

    /* Disable attempts to try to process the next record instead of returning after a
       non-app record. Avoids hangs in blocking mode, when using SSL_read() and a
       non-application record was sent without any application data. */
    /*SSL_CTX_clear_mode(ctx, SSL_MODE_AUTO_RETRY);*/

    SSL_CTX_sess_set_cache_size(ctx, 128);

    /* Set user defined ciphers, cipher suites, and security level */
    if ((ciphers != NULL) && !SSL_CTX_set_cipher_list(ctx, ciphers)) {
	Tcl_AppendResult(interp, "Set ciphers failed: No valid ciphers", (char *)NULL);
	Tcl_AppendResult(interp, "Set ciphers failed: No valid ciphers", (char *) NULL);
	SSL_CTX_free(ctx);
	return NULL;
    }
    if ((ciphersuites != NULL) && !SSL_CTX_set_ciphersuites(ctx, ciphersuites)) {
	Tcl_AppendResult(interp, "Set cipher suites failed: No valid ciphers", (char *)NULL);
	Tcl_AppendResult(interp, "Set cipher suites failed: No valid ciphers", (char *) NULL);
	SSL_CTX_free(ctx);
	return NULL;
    }

    /* set automatic curve selection */
    SSL_CTX_set_ecdh_auto(ctx, 1);

    /* Set security level */
    if (level > -1 && level < 6) {
	/* SSL_set_security_level */
	SSL_CTX_set_security_level(ctx, level);
    }

    /* set some callbacks */
    SSL_CTX_set_default_passwd_cb(ctx, PasswordCallback);
    SSL_CTX_set_default_passwd_cb_userdata(ctx, (void *)statePtr);

    /* read a Diffie-Hellman parameters file, or use the built-in one */
    Tcl_DStringInit(&ds);
#ifdef OPENSSL_NO_DH
    if (DHparams != NULL) {
	Tcl_AppendResult(interp, "DH parameter support not available", (char *)NULL);
	Tcl_AppendResult(interp, "DH parameter support not available", (char *) NULL);
	SSL_CTX_free(ctx);
	return NULL;
    }
#else
    {
	DH* dh;
	if (DHparams != NULL) {
	    BIO *bio;

	    bio = BIO_new_file(F2N(DHparams, &ds), "r");
	    if (!bio) {
		Tcl_DStringFree(&ds);
		Tcl_AppendResult(interp, "Could not find DH parameters file", (char *)NULL);
		Tcl_AppendResult(interp, "Could not find DH parameters file", (char *) NULL);
		SSL_CTX_free(ctx);
		return NULL;
	    }

	    dh = PEM_read_bio_DHparams(bio, NULL, NULL, NULL);
	    BIO_free(bio);
	    Tcl_DStringFree(&ds);
	    if (!dh) {
		Tcl_AppendResult(interp, "Could not read DH parameters from file", (char *)NULL);
		Tcl_AppendResult(interp, "Could not read DH parameters from file", (char *) NULL);
		SSL_CTX_free(ctx);
		return NULL;
	    }
	    SSL_CTX_set_tmp_dh(ctx, dh);
	    DH_free(dh);

	} else {
	    /* Use well known DH parameters that have built-in support in OpenSSL */
	    if (!SSL_CTX_set_dh_auto(ctx, 1)) {
		Tcl_AppendResult(interp, "Could not enable set DH auto: ", GET_ERR_REASON(), (char *)NULL);
		Tcl_AppendResult(interp, "Could not enable set DH auto: ", GET_ERR_REASON(), (char *) NULL);
		SSL_CTX_free(ctx);
		return NULL;
	    }
	}
    }
#endif

    /* set our certificate */
    load_private_key = 0;
    if (certfile != NULL) {
	load_private_key = 1;

	if (SSL_CTX_use_certificate_file(ctx, F2N(certfile, &ds), SSL_FILETYPE_PEM) <= 0) {
	    Tcl_DStringFree(&ds);
	    Tcl_AppendResult(interp, "unable to set certificate file ", certfile, ": ",
		    GET_ERR_REASON(), (char *)NULL);
		GET_ERR_REASON(), (char *) NULL);
	    SSL_CTX_free(ctx);
	    return NULL;
	}
	Tcl_DStringFree(&ds);

    } else if (cert != NULL) {
	load_private_key = 1;
	if (SSL_CTX_use_certificate_ASN1(ctx, cert_len, cert) <= 0) {
	if (SSL_CTX_use_certificate_ASN1(ctx, (int) cert_len, cert) <= 0) {
	    Tcl_AppendResult(interp, "unable to set certificate: ",
		    GET_ERR_REASON(), (char *)NULL);
		GET_ERR_REASON(), (char *) NULL);
	    SSL_CTX_free(ctx);
	    return NULL;
	}
    } else {
	certfile = (char*)X509_get_default_cert_file();

	if (SSL_CTX_use_certificate_file(ctx, certfile, SSL_FILETYPE_PEM) <= 0) {
#if 0
	    Tcl_AppendResult(interp, "unable to use default certificate file ", certfile, ": ",
		    GET_ERR_REASON(), (char *)NULL);
		GET_ERR_REASON(), (char *) NULL);
	    SSL_CTX_free(ctx);
	    return NULL;
#endif
	}
    }

    /* set our private key */

	    }

	    if (SSL_CTX_use_PrivateKey_file(ctx, F2N(keyfile, &ds), SSL_FILETYPE_PEM) <= 0) {
		Tcl_DStringFree(&ds);
		/* flush the passphrase which might be left in the result */
		Tcl_SetResult(interp, NULL, TCL_STATIC);
		Tcl_AppendResult(interp, "unable to set public key file ", keyfile, " ",
			GET_ERR_REASON(), (char *)NULL);
		    GET_ERR_REASON(), (char *) NULL);
		SSL_CTX_free(ctx);
		return NULL;
	    }
	    Tcl_DStringFree(&ds);

	} else if (key != NULL) {
	    if (SSL_CTX_use_PrivateKey_ASN1(EVP_PKEY_RSA, ctx, key,key_len) <= 0) {
	    if (SSL_CTX_use_PrivateKey_ASN1(EVP_PKEY_RSA, ctx, key, (int) key_len) <= 0) {
		/* flush the passphrase which might be left in the result */
		Tcl_SetResult(interp, NULL, TCL_STATIC);
		Tcl_AppendResult(interp, "unable to set public key: ", GET_ERR_REASON(), (char *)NULL);
		Tcl_AppendResult(interp, "unable to set public key: ", GET_ERR_REASON(), (char *) NULL);
		SSL_CTX_free(ctx);
		return NULL;
	    }
	}
	/* Now we know that a key and cert have been set against
	 * the SSL context */
	if (!SSL_CTX_check_private_key(ctx)) {
	    Tcl_AppendResult(interp, "private key does not match the certificate public key",
			     (char *)NULL);
			     (char *) NULL);
	    SSL_CTX_free(ctx);
	    return NULL;
	}
    }

    /* Set to use default location and file for Certificate Authority (CA) certificates. The
     * verify path and store can be overridden by the SSL_CERT_DIR env var. The verify file can
     * be overridden by the SSL_CERT_FILE env var. */
    /* Set to use the default location and file for Certificate Authority (CA) certificates.
     * The default CA certificates directory is called certs in the default OpenSSL
     * directory. It contains the CA certificates in PEM format, with one certificate per
     * file. The verify path and store can be overridden by the SSL_CERT_DIR env var. The
     * default CA certificates file is called cert.pem in the default OpenSSL directory.
     * The verify file can be overridden by the SSL_CERT_FILE env var. */
    if (!SSL_CTX_set_default_verify_paths(ctx)) {
	abort++;
    }

    /* Overrides for the CA verify path and file */
    {
#if OPENSSL_VERSION_NUMBER < 0x30000000L
	if (CApath != NULL || CAfile != NULL) {
	    Tcl_DString ds1;
	    Tcl_DStringInit(&ds1);

	    if (!SSL_CTX_load_verify_locations(ctx, F2N(CAfile, &ds), F2N(CApath, &ds1))) {
		abort++;
		return NULL;
	    }
	    Tcl_DStringFree(&ds);
	    Tcl_DStringFree(&ds1);

	    /* Set list of CAs to send to client when requesting a client certificate */
	    /* https://sourceforge.net/p/tls/bugs/57/ */
	    /* XXX:TODO: Let the user supply values here instead of something that exists on the filesystem */
	    STACK_OF(X509_NAME) *certNames = SSL_load_client_CA_file(F2N(CAfile, &ds));
	    if (certNames != NULL) {
		SSL_CTX_set_client_CA_list(ctx, certNames);
	    }
	    Tcl_DStringFree(&ds);
	}

#else
	/* Set directory containing CA certificates in PEM format. */
	if (CApath != NULL) {
	    if (!SSL_CTX_load_verify_dir(ctx, F2N(CApath, &ds))) {
		abort++;
	    }
	    Tcl_DStringFree(&ds);
	}

	/* Set URI for to a store, which may be a single container or a catalog of containers. */
	if (CAfile != NULL) {
	    if (!SSL_CTX_load_verify_file(ctx, F2N(CAfile, &ds))) {
	if (CAstore != NULL) {
	    if (!SSL_CTX_load_verify_store(ctx, F2N(CAstore, &ds))) {
		abort++;
	    }
	    Tcl_DStringFree(&ds);

	    /* Set list of CAs to send to client when requesting a client certificate */
	    STACK_OF(X509_NAME) *certNames = SSL_load_client_CA_file(F2N(CAfile, &ds));
	    if (certNames != NULL) {
		SSL_CTX_set_client_CA_list(ctx, certNames);
	    }
	    Tcl_DStringFree(&ds);
	}

	/* Set file of CA certificates in PEM format.  */
	if (CAfile != NULL) {
	    Tcl_Obj *cafileobj = Tcl_NewStringObj(CAfile, -1);
	    Tcl_IncrRefCount(cafileobj);

	    Tcl_Obj *fsinfo = Tcl_FSFileSystemInfo(cafileobj);
	    if (fsinfo) {
		Tcl_IncrRefCount(fsinfo);

		Tcl_Obj *fstype = NULL;
		Tcl_ListObjIndex(interp, fsinfo, 0, &fstype);

		if (Tcl_StringMatch("native", Tcl_GetString(fstype))) {
		    if (!SSL_CTX_load_verify_file(ctx, F2N(CAfile, &ds))) {
			abort++;
		    }
		    Tcl_DStringFree(&ds);

		    /* Set list of CAs to send to client when requesting a client certificate */
		    STACK_OF(X509_NAME) *certNames = SSL_load_client_CA_file(F2N(CAfile, &ds));
		    if (certNames != NULL) {
			SSL_CTX_set_client_CA_list(ctx, certNames);
		    }
		    Tcl_DStringFree(&ds);

		} else {
		    /* Load certificate into memory */
		    if (!TlsLoadClientCAFileFromMemory(interp, ctx, cafileobj)) {
			abort++;
		    }
		}
		Tcl_DecrRefCount(fsinfo);

	    } else {
		abort++; /* Path is not recognized */
	    }
	    Tcl_DecrRefCount(cafileobj);
	}
#endif
    }

    if (abort > 0) {
	/* return error */
    }
    return ctx;
}

/*
 *-------------------------------------------------------------------
 *
 * StatusObjCmd -- return certificate for connected peer.
 * StatusObjCmd -- return certificate for connected peer info.
 *
 * Results:
 *	A standard Tcl result.
 *
 * Side effects:
 *	None.
 *
 *-------------------------------------------------------------------
 */
static int
StatusObjCmd(
StatusObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) {
    TCL_UNUSED(void *),
    Tcl_Interp *interp,
    int objc,
    Tcl_Obj	*const objv[])
{
    State *statePtr;
    X509 *peer;
    Tcl_Obj *objPtr;
    Tcl_Channel chan;
    char *channelName, *ciphers;
    int mode;
    const unsigned char *proto;
    unsigned int len;
    int nid, res;
    (void) clientData;

    dprintf("Called");

    if (objc < 2 || objc > 3 || (objc == 3 && !strcmp(Tcl_GetString(objv[1]), "-local"))) {
	Tcl_WrongNumArgs(interp, 1, objv, "?-local? channel");
	return TCL_ERROR;
    }

    /* Get channel Id */
    channelName = Tcl_GetString(objv[(objc == 2 ? 1 : 2)]);
    chan = Tcl_GetChannel(interp, channelName, &mode);
    if (chan == (Tcl_Channel) NULL) {
	return TCL_ERROR;
    }

    /* Make sure to operate on the topmost channel */
    chan = Tcl_GetTopChannel(chan);
    if (Tcl_GetChannelType(chan) != Tls_ChannelType()) {
	Tcl_AppendResult(interp, "bad channel \"", Tcl_GetChannelName(chan),
		"\": not a TLS channel", (char *)NULL);
	Tcl_SetErrorCode(interp, "TLS", "STATUS", "CHANNEL", "INVALID", (char *)NULL);
		"\": not a TLS channel", (char *) NULL);
	Tcl_SetErrorCode(interp, "TLS", "STATUS", "CHANNEL", "INVALID", (char *) NULL);
	return TCL_ERROR;
    }
    statePtr = (State *) Tcl_GetChannelInstanceData(chan);

    /* Get certificate for peer or self */
    if (objc == 2) {
	peer = SSL_get_peer_certificate(statePtr->ssl);
    } else {
	peer = SSL_get_certificate(statePtr->ssl);
    }
    /* Get X509 certificate info */
    if (peer) {
	objPtr = Tls_NewX509Obj(interp, peer);
	objPtr = Tls_NewX509Obj(interp, peer, 1);
	if (objc == 2) {
	    X509_free(peer);
	    peer = NULL;
	}
    } else {
	objPtr = Tcl_NewListObj(0, NULL);
    }

    /* Verify the X509 certificate presented by the peer */
    LAPPEND_STR(interp, objPtr, "verifyResult",
	X509_verify_cert_error_string(SSL_get_verify_result(statePtr->ssl)), -1);

    /* Verify mode */
    mode = SSL_get_verify_mode(statePtr->ssl);
    if (mode && SSL_VERIFY_NONE) {
    if (mode & SSL_VERIFY_NONE) {
	LAPPEND_STR(interp, objPtr, "verifyMode", "none", -1);
    } else {
	Tcl_Obj *listObjPtr = Tcl_NewListObj(0, NULL);
	if (mode && SSL_VERIFY_PEER) {
	if (mode & SSL_VERIFY_PEER) {
	    Tcl_ListObjAppendElement(interp, listObjPtr, Tcl_NewStringObj("peer", -1));
	}
	if (mode && SSL_VERIFY_FAIL_IF_NO_PEER_CERT) {
	if (mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT) {
	    Tcl_ListObjAppendElement(interp, listObjPtr, Tcl_NewStringObj("fail if no peer cert", -1));
	}
	if (mode && SSL_VERIFY_CLIENT_ONCE) {
	if (mode & SSL_VERIFY_CLIENT_ONCE) {
	    Tcl_ListObjAppendElement(interp, listObjPtr, Tcl_NewStringObj("client once", -1));
	}
	if (mode && SSL_VERIFY_POST_HANDSHAKE) {
	if (mode & SSL_VERIFY_POST_HANDSHAKE) {
	    Tcl_ListObjAppendElement(interp, listObjPtr, Tcl_NewStringObj("post handshake", -1));
	}
	LAPPEND_OBJ(interp, objPtr, "verifyMode", listObjPtr)
    }

    /* Verify mode depth */
    LAPPEND_INT(interp, objPtr, "verifyDepth", SSL_get_verify_depth(statePtr->ssl));

	res = SSL_get_peer_signature_nid(statePtr->ssl, &nid);
    } else {
	res = SSL_get_signature_nid(statePtr->ssl, &nid);
    }
    if (!res) {nid = 0;}
    LAPPEND_STR(interp, objPtr, "signatureHashAlgorithm", OBJ_nid2ln(nid), -1);

    /* Added in OpenSSL 1.1.1a */
#if OPENSSL_VERSION_NUMBER > 0x10101000L
    if (objc == 2) {
	res = SSL_get_peer_signature_type_nid(statePtr->ssl, &nid);
    } else {
	res = SSL_get_signature_type_nid(statePtr->ssl, &nid);
    }
    if (!res) {nid = 0;}
    LAPPEND_STR(interp, objPtr, "signatureType", OBJ_nid2ln(nid), -1);
#endif

    Tcl_SetObjResult(interp, objPtr);
    return TCL_OK;
}

/*
 *-------------------------------------------------------------------
 *
 * ConnectionInfoObjCmd -- return connection info from OpenSSL.
 *
 * Results:
 *	A list of connection info
  *
 *-------------------------------------------------------------------
 */

static int ConnectionInfoObjCmd(
static int ConnectionInfoObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) {
    TCL_UNUSED(void *),
    Tcl_Interp *interp,
    int objc,
    Tcl_Obj *const objv[])
{
    Tcl_Channel chan;		/* The channel to set a mode on */
    State *statePtr;		/* client state for ssl socket */
    Tcl_Obj *objPtr, *listPtr;
    const SSL *ssl;
    const SSL_CIPHER *cipher;
    const SSL_SESSION *session;
    const EVP_MD *md;
    (void) clientData;

    dprintf("Called");

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

    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);
    if (Tcl_GetChannelType(chan) != Tls_ChannelType()) {
	Tcl_AppendResult(interp, "bad channel \"", Tcl_GetChannelName(chan),
	    "\": not a TLS channel", (char *)NULL);
	Tcl_SetErrorCode(interp, "TLS", "CONNECTION", "CHANNEL", "INVALID", (char *)NULL);
	    "\": not a TLS channel", (char *) NULL);
	Tcl_SetErrorCode(interp, "TLS", "CONNECTION", "CHANNEL", "INVALID", (char *) NULL);
	return TCL_ERROR;
    }

    objPtr = Tcl_NewListObj(0, NULL);

    /* Connection info */
    statePtr = (State *)Tcl_GetChannelInstanceData(chan);
    ssl = statePtr->ssl;
    if (ssl != NULL) {
	const unsigned char *proto;
	unsigned int ulen;

	/* Initialization finished */
	LAPPEND_BOOL(interp, objPtr, "init_finished", SSL_is_init_finished(ssl));

	/* connection state */
	LAPPEND_STR(interp, objPtr, "state", SSL_state_string_long(ssl), -1);

	/* Get SNI requested server name */
	LAPPEND_STR(interp, objPtr, "servername", SSL_get_servername(ssl, TLSEXT_NAMETYPE_host_name), -1);

	/* Report the selected protocol as a result of the negotiation */
	SSL_get0_alpn_selected(statePtr->ssl, &proto, &ulen);
	LAPPEND_STR(interp, objPtr, "alpn", (char *)proto, (Tcl_Size) ulen);

	/* Get protocol */
	LAPPEND_STR(interp, objPtr, "protocol", SSL_get_version(ssl), -1);

	/* Renegotiation allowed */
	LAPPEND_BOOL(interp, objPtr, "renegotiation_allowed", SSL_get_secure_renegotiation_support((SSL *) ssl));

	/* Get security level */
	LAPPEND_INT(interp, objPtr, "security_level", SSL_get_security_level(ssl));

	/* Session info */
	LAPPEND_BOOL(interp, objPtr, "session_reused", SSL_session_reused(ssl));

	/* Is server info */
	LAPPEND_BOOL(interp, objPtr, "is_server", SSL_is_server(ssl));

	/* Is DTLS */
	LAPPEND_BOOL(interp, objPtr, "is_dtls", SSL_is_dtls(ssl));

#if OPENSSL_VERSION_NUMBER >= 0x30200000L
	/* Is QUIC */
	LAPPEND_BOOL(interp, objPtr, "is_quic", SSL_is_quic(ssl));

	/* Is TLS */
	LAPPEND_BOOL(interp, objPtr, "is_tls", SSL_is_tls(ssl));
#endif

	/* DANE TLS authentication */
	LAPPEND_BOOL(interp, objPtr, "dane_auth", SSL_get0_dane((SSL *)ssl) != NULL);

	/* Waiting for async */
	LAPPEND_BOOL(interp, objPtr, "waiting_for_async", SSL_waiting_for_async((SSL *)ssl));

	/* Time-out */
	LAPPEND_LONG(interp, objPtr, "time-out", SSL_get_default_timeout(ssl));

	/* Is Certificate Transparency validation enabled */
	LAPPEND_BOOL(interp, objPtr, "ct_enabled", SSL_ct_is_enabled(ssl));
    }

    /* Cipher info */
    cipher = SSL_get_current_cipher(ssl);
    if (cipher != NULL) {
	char buf[BUFSIZ] = {0};
	int bits, alg_bits;

 *
 * Side effects:
 *	None.
 *
 *-------------------------------------------------------------------
 */
static int
VersionObjCmd(
VersionObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) {
    TCL_UNUSED(void *),
    Tcl_Interp *interp,
    TCL_UNUSED(int) /* objc */,
    TCL_UNUSED(Tcl_Obj *const *) /* objv */)
{
    Tcl_Obj *objPtr;
    (void) clientData;
    (void) objc;
    (void) objv;

    dprintf("Called");

    objPtr = Tcl_NewStringObj(OPENSSL_VERSION_TEXT, -1);

    Tcl_SetObjResult(interp, objPtr);

    return TCL_OK;
}

/*
 *-------------------------------------------------------------------
 *
 * MiscObjCmd -- misc commands
 *
 * Results:
 *	A standard Tcl result.
 *
 * Side effects:
 *	None.
 *
 *-------------------------------------------------------------------
 */
static int
MiscObjCmd(
    TCL_UNUSED(void *),
    Tcl_Interp *interp,
    int objc,
    Tcl_Obj *const objv[])
MiscObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) {
{
    static const char *commands [] = { "req", "strreq", NULL };
    enum command { C_REQ, C_STRREQ, C_DUMMY };
    Tcl_Size cmd;
    int isStr;
    char buffer[16384];
    (void) clientData;

    dprintf("Called");

    if (objc < 2) {
	Tcl_WrongNumArgs(interp, 1, objv, "subcommand ?args?");
	return TCL_ERROR;
    }

    switch ((enum command) cmd) {
	case C_REQ:
	case C_STRREQ: {
	    EVP_PKEY *pkey=NULL;
	    X509 *cert=NULL;
	    X509_NAME *name=NULL;
	    Tcl_Obj **listv;
	    Tcl_Size listc,i;
	    Tcl_Size listc;
	    int i;

	    BIO *out=NULL;

	    const char *k_C="",*k_ST="",*k_L="",*k_O="",*k_OU="",*k_CN="",*k_Email="";
	    char *k_C="",*k_ST="",*k_L="",*k_O="",*k_OU="",*k_CN="",*k_Email="";
	    char *keyout,*pemout,*str;
	    int keysize,serial=0,days=365;

#if OPENSSL_VERSION_NUMBER < 0x30000000L
	    BIGNUM *bne = NULL;
	    RSA *rsa = NULL;
#else

	    pkey = EVP_PKEY_new();
	    if (bne == NULL || rsa == NULL || pkey == NULL || !BN_set_word(bne,RSA_F4) ||
		!RSA_generate_key_ex(rsa, keysize, bne, NULL) || !EVP_PKEY_assign_RSA(pkey, rsa)) {
		EVP_PKEY_free(pkey);
		/* RSA_free(rsa); freed by EVP_PKEY_free */
		BN_free(bne);
#else
	    pkey = EVP_RSA_gen((unsigned int)keysize);
	    pkey = EVP_RSA_gen((unsigned int) keysize);
	    ctx = EVP_PKEY_CTX_new(pkey,NULL);
	    if (pkey == NULL || ctx == NULL || !EVP_PKEY_keygen_init(ctx) ||
		!EVP_PKEY_CTX_set_rsa_keygen_bits(ctx, keysize) || !EVP_PKEY_keygen(ctx, &pkey)) {
		EVP_PKEY_free(pkey);
		EVP_PKEY_CTX_free(ctx);
#endif
		Tcl_SetResult(interp,"Error generating private key",NULL);

 *	none
 *
 * Side effects:
 *	Frees all the state
 *
 *-------------------------------------------------------------------
 */
#undef Tls_Free
void
#if TCL_MAJOR_VERSION > 8
Tls_Free(void *blockPtr)
Tls_Free(tls_free_type *blockPtr) {
#else
Tls_Free(char *blockPtr)
#endif
{
    State *statePtr = (State *)blockPtr;

    dprintf("Called");

    Tls_Clean(statePtr);
    ckfree(blockPtr);
}

     * we're assuming here that we're single-threaded
     */
    if (statePtr->timer != (Tcl_TimerToken) NULL) {
	Tcl_DeleteTimerHandler(statePtr->timer);
	statePtr->timer = NULL;
    }

    if (statePtr->protos) {
	ckfree(statePtr->protos);
	statePtr->protos = NULL;
    }
    if (statePtr->bio) {
	/* This will call SSL_shutdown. Bug 1414045 */
    /* Remove callbacks */
	dprintf("BIO_free_all(%p)", statePtr->bio);
	BIO_free_all(statePtr->bio);
	statePtr->bio = NULL;
    }
    if (statePtr->ssl) {
	dprintf("SSL_free(%p)", statePtr->ssl);
	SSL_free(statePtr->ssl);
	statePtr->ssl = NULL;
    }
    if (statePtr->ctx) {
	SSL_CTX_free(statePtr->ctx);
	statePtr->ctx = NULL;
    }
    if (statePtr->callback) {
	Tcl_DecrRefCount(statePtr->callback);
	statePtr->callback = NULL;
    }
    if (statePtr->password) {
	Tcl_DecrRefCount(statePtr->password);
	statePtr->password = NULL;
    }
    if (statePtr->vcmd) {
	Tcl_DecrRefCount(statePtr->vcmd);
	statePtr->vcmd = NULL;
    }

    if (statePtr->protos) {
	ckfree(statePtr->protos);
	statePtr->protos = NULL;
    }

    if (statePtr->bio) {
	/* This will call SSL_shutdown. Bug 1414045 */
	dprintf("BIO_free_all(%p)", statePtr->bio);
	BIO_free_all(statePtr->bio);
	statePtr->bio = NULL;
    }

    if (statePtr->ssl) {
	dprintf("SSL_free(%p)", statePtr->ssl);
	SSL_free(statePtr->ssl);
	statePtr->ssl = NULL;
    }

    if (statePtr->ctx) {
	SSL_CTX_free(statePtr->ctx);
	statePtr->ctx = NULL;
    }

    dprintf("Returning");
}

/*
 *----------------------------------------------------------------------
 *

			    ".static"
#endif
		), NULL);
    }
    return TCL_OK;
}

/*
 *------------------------------------------------------*
 *
 * TlsLibShutdown --
 *
 *	Shutdown SSL library once per application
 *
 * Results:
 *	A standard TCL result
 *
 * Side effects:
 *	Shutdown SSL library
 *
 *------------------------------------------------------*
 */
void TlsLibShutdown(ClientData clientData) {
    dprintf("Called");

    BIO_cleanup();
}

/*
 *------------------------------------------------------*
 *
 *	TlsLibInit --
 *
 *	Initializes SSL library once per application
 *
 * Results:
 *	A standard Tcl result
 *
 * Side effects:
 *	Initializes SSL library
 *
 *------------------------------------------------------*
 */
static int TlsLibInit() {
    static int initialized = 0;

    dprintf("Called");

    if (!initialized) {
	/* Initialize BOTH libcrypto and libssl. */
	if (!OPENSSL_init_ssl(OPENSSL_INIT_LOAD_SSL_STRINGS | OPENSSL_INIT_LOAD_CRYPTO_STRINGS
	    | OPENSSL_INIT_ADD_ALL_CIPHERS | OPENSSL_INIT_ADD_ALL_DIGESTS
	    | OPENSSL_INIT_LOAD_CONFIG | OPENSSL_INIT_ASYNC, NULL)) {
	    return TCL_ERROR;
	}

	/* Create BIO handlers */
	BIO_new_tcl(NULL, 0);

	/* Create exit handler */
	Tcl_CreateExitHandler(TlsLibShutdown, NULL);
	initialized = 1;
    }
    return TCL_OK;
}

/* Init script */
static const char tlsTclInitScript[] = {
#include "tls.tcl.h"
};

/*
 *-------------------------------------------------------------------
 *
 * Tls_Init --
 *
 *	This is a package initialization procedure, which is called
 *	by Tcl when this package is to be added to an interpreter.
 *	by TCL when this package is to be added to an interpreter.
 *
 * Results:  Ssl configured and loaded
 * Results:
 *	Initializes structures and creates commands.
 *
 * Side effects:
 *	 create the ssl command, initialize ssl context
 *	 Create the commands
 *
 *-------------------------------------------------------------------
 */

#if TCL_MAJOR_VERSION > 8
#define MIN_VERSION "9.0"
#else
#define MIN_VERSION "8.5"
#endif

static const char tlsTclInitScript[] = {
#include "tls.tcl.h"
	0x00
    };

DLLEXPORT int Tls_Init(Tcl_Interp *interp) {

    dprintf("Called");

#ifdef USE_TCL_STUBS
    if (Tcl_InitStubs(interp, MIN_VERSION, 0) == NULL) {
	return TCL_ERROR;
    }
#endif
    if (Tcl_PkgRequire(interp, "Tcl", MIN_VERSION, 0) == NULL) {
#else
    if (Tcl_PkgRequireEx(interp, "Tcl", MIN_VERSION, 0, NULL) == NULL) {
	return TCL_ERROR;
    }
#endif

    if (TlsLibInit(0) != TCL_OK) {
	Tcl_AppendResult(interp, "could not initialize SSL library", (char *)NULL);
    if (TlsLibInit() != TCL_OK) {
	Tcl_AppendResult(interp, "could not initialize SSL library", (char *) NULL);
	return TCL_ERROR;
    }

    Tcl_CreateObjCommand(interp, "::tls::ciphers", CiphersObjCmd, (void *) NULL, (Tcl_CmdDeleteProc *) NULL);
    Tcl_CreateObjCommand(interp, "::tls::connection", ConnectionInfoObjCmd, (void *) NULL, (Tcl_CmdDeleteProc *) NULL);
    Tcl_CreateObjCommand(interp, "::tls::handshake", HandshakeObjCmd, (void *) NULL, (Tcl_CmdDeleteProc *) NULL);
    Tcl_CreateObjCommand(interp, "::tls::import", ImportObjCmd, (void *) NULL, (Tcl_CmdDeleteProc *) NULL);
    Tcl_CreateObjCommand(interp, "::tls::unimport", UnimportObjCmd, (void *) NULL, (Tcl_CmdDeleteProc *) NULL);
    Tcl_CreateObjCommand(interp, "::tls::status", StatusObjCmd, (void *) NULL, (Tcl_CmdDeleteProc *) NULL);
    Tcl_CreateObjCommand(interp, "::tls::version", VersionObjCmd, (void *) NULL, (Tcl_CmdDeleteProc *) NULL);
    Tcl_CreateObjCommand(interp, "::tls::misc", MiscObjCmd, (void *) NULL, (Tcl_CmdDeleteProc *) NULL);
    Tcl_CreateObjCommand(interp, "::tls::protocols", ProtocolsObjCmd, (void *) NULL, (Tcl_CmdDeleteProc *) NULL);
    Tcl_CreateObjCommand(interp, "::tls::ciphers", CiphersObjCmd, (ClientData) NULL, (Tcl_CmdDeleteProc *) NULL);
    Tcl_CreateObjCommand(interp, "::tls::connection", ConnectionInfoObjCmd, (ClientData) NULL, (Tcl_CmdDeleteProc *) NULL);
    Tcl_CreateObjCommand(interp, "::tls::handshake", HandshakeObjCmd, (ClientData) NULL, (Tcl_CmdDeleteProc *) NULL);
    Tcl_CreateObjCommand(interp, "::tls::import", ImportObjCmd, (ClientData) NULL, (Tcl_CmdDeleteProc *) NULL);
    Tcl_CreateObjCommand(interp, "::tls::unimport", UnimportObjCmd, (ClientData) NULL, (Tcl_CmdDeleteProc *) NULL);
    Tcl_CreateObjCommand(interp, "::tls::unstack", UnimportObjCmd, (ClientData) NULL, (Tcl_CmdDeleteProc *) NULL);
    Tcl_CreateObjCommand(interp, "::tls::status", StatusObjCmd, (ClientData) NULL, (Tcl_CmdDeleteProc *) NULL);
    Tcl_CreateObjCommand(interp, "::tls::version", VersionObjCmd, (ClientData) NULL, (Tcl_CmdDeleteProc *) NULL);
    Tcl_CreateObjCommand(interp, "::tls::misc", MiscObjCmd, (ClientData) NULL, (Tcl_CmdDeleteProc *) NULL);
    Tcl_CreateObjCommand(interp, "::tls::protocols", ProtocolsObjCmd, (ClientData) NULL, (Tcl_CmdDeleteProc *) NULL);

    BuildInfoCommand(interp);

    if (interp && Tcl_Eval(interp, tlsTclInitScript) != TCL_OK) {
	return TCL_ERROR;
    }

    return Tcl_PkgProvide(interp, PACKAGE_NAME, PACKAGE_VERSION);
}

/*
 *------------------------------------------------------*
 *-------------------------------------------------------------------
 *
 *	Tls_SafeInit --
 *
 *	------------------------------------------------*
 *	Standard procedure required by 'load'.
 *	This is a package initialization procedure for safe interps.
 *	Initializes this extension for a safe interpreter.
 *	------------------------------------------------*
 *
 *	Side effects:
 *		As of 'Tls_Init'
 * Results:
 *	Same as of 'Tls_Init'
 *
 * Side effects:
 *	Result:
 *	Same as of 'Tls_Init'
 *		A standard Tcl error code.
 *
 *------------------------------------------------------*
 *-------------------------------------------------------------------
 */

DLLEXPORT int Tls_SafeInit(Tcl_Interp *interp) {
    dprintf("Called");
    return Tls_Init(interp);
}

/*
 *------------------------------------------------------*
 *
 *	TlsLibInit --
 *
 *	------------------------------------------------*
 *	Initializes SSL library once per application
 *	------------------------------------------------*
 *
 *	Side effects:
 *		initializes SSL library
 *
 *	Result:
 *		none
 *
 *------------------------------------------------------*
 */
static int TlsLibInit(int uninitialize) {
    static int initialized = 0;
    int status = TCL_OK;
#if defined(OPENSSL_THREADS) && defined(TCL_THREADS)
    size_t num_locks;
#endif

    if (uninitialize) {
	if (!initialized) {
	    dprintf("Asked to uninitialize, but we are not initialized");

	    return TCL_OK;
	}

	dprintf("Asked to uninitialize");

#if defined(OPENSSL_THREADS) && defined(TCL_THREADS)
	Tcl_MutexLock(&init_mx);

	if (locks) {
	    free(locks);
	    locks = NULL;
	    locksCount = 0;
	}
#endif
	initialized = 0;

#if defined(OPENSSL_THREADS) && defined(TCL_THREADS)
	Tcl_MutexUnlock(&init_mx);
#endif

	return TCL_OK;
    }

    if (initialized) {
	dprintf("Called, but using cached value");
	return status;
    }

    dprintf("Called");

#if defined(OPENSSL_THREADS) && defined(TCL_THREADS)
    Tcl_MutexLock(&init_mx);
#endif
    initialized = 1;

#if defined(OPENSSL_THREADS) && defined(TCL_THREADS)
    num_locks = 1;
    locksCount = (int) num_locks;
    locks = malloc(sizeof(*locks) * num_locks);
    memset(locks, 0, sizeof(*locks) * num_locks);
#endif

    /* Initialize BOTH libcrypto and libssl. */
    OPENSSL_init_ssl(OPENSSL_INIT_LOAD_SSL_STRINGS | OPENSSL_INIT_LOAD_CRYPTO_STRINGS
	| OPENSSL_INIT_ADD_ALL_CIPHERS | OPENSSL_INIT_ADD_ALL_DIGESTS, NULL);

    BIO_new_tcl(NULL, 0);

#if 0
    /*
     * XXX:TODO: Remove this code and replace it with a check
     * for enough entropy and do not try to create our own
     * terrible entropy
     */
    /*
     * Seed the random number generator in the SSL library,
     * using the do/while construct because of the bug note in the
     * OpenSSL FAQ at http://www.openssl.org/support/faq.html#USER1
     *
     * The crux of the problem is that Solaris 7 does not have a
     * /dev/random or /dev/urandom device so it cannot gather enough
     * entropy from the RAND_seed() when TLS initializes and refuses
     * to go further. Earlier versions of OpenSSL carried on regardless.
     */
    srand((unsigned int) time((time_t *) NULL));
    do {
	for (i = 0; i < 16; i++) {
	    rnd_seed[i] = 1 + (char) (255.0 * rand()/(RAND_MAX+1.0));
	}
	RAND_seed(rnd_seed, sizeof(rnd_seed));
    } while (RAND_status() != 1);
#endif

#if defined(OPENSSL_THREADS) && defined(TCL_THREADS)
    Tcl_MutexUnlock(&init_mx);
#endif

    return status;
}