int depth		= X509_STORE_CTX_get_error_depth(ctx);
    int err		= X509_STORE_CTX_get_error(ctx);

    dprintf("Called");
    dprintf("VerifyCallback: %d", ok);

    if (statePtr->vcmd == (Tcl_Obj*)NULL) {
	/* Use ok value if verification is required */
	if (statePtr->vflags & SSL_VERIFY_FAIL_IF_NO_PEER_CERT) {
	    return ok;
	} else {
	    return 1;
	}
    } else if (cert == NULL || ssl == NULL) {
	return 0;
    }

    dprintf("VerifyCallback: eval callback");

    /* Create command to eval */
    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, 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; */

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

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

    /* statePtr->flags &= ~(TLS_TCL_CALLBACK); */
    return(ok);	/* By default, leave verification unchanged. */
}

/*
 *-------------------------------------------------------------------

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

    if (ret < 0 && ((statePtr->flags & TLS_TCL_ASYNC) && (err == EAGAIN))) {
	dprintf("Async set and err = EAGAIN");
	ret = 0;
    } else if (ret < 0) {
	long result;
	errStr = statePtr->err;
	Tcl_ResetResult(interp);
	Tcl_SetErrno(err);

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

	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_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);
	}

/*
 * Copyright (C) 1997-2000 Matt Newman <matt@novadigm.com>
 *
 * Provides BIO layer to interface openssl to Tcl.
 * Provides BIO layer to interface OpenSSL to TCL.
 */

#include "tlsInt.h"

/* Called by SSL_write() */
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);

    dprintf("[chan=%p] BioWrite(%p, <buf>, %d)", (void *)chan, (void *) bio, bufLen);

    ret = Tcl_WriteRaw(chan, buf, (Tcl_Size) bufLen);

    tclEofChan = Tcl_Eof(chan);
    tclErrno = Tcl_GetErrno();

    dprintf("[chan=%p] BioWrite(%d) -> %" TCL_SIZE_MODIFIER "d [tclEof=%d; tclErrno=%d]",
	(void *) chan, bufLen, ret, tclEofChan, Tcl_GetErrno());
	(void *) chan, bufLen, ret, tclEofChan, tclErrno);

    BIO_clear_flags(bio, BIO_FLAGS_WRITE | BIO_FLAGS_SHOULD_RETRY);

    if (tclEofChan && ret <= 0) {
	dprintf("Got EOF while reading, returning a Connection Reset error which maps to Soft EOF");
	Tcl_SetErrno(ECONNRESET);
	ret = 0;

	if (tclErrno == EAGAIN) {
	    dprintf("It's EAGAIN");
	} else {
	    dprintf("It's an unexpected error: %s/%i", Tcl_ErrnoMsg(tclErrno), tclErrno);
	}

    } else {
	dprintf("Successfully wrote some data");
	dprintf("Successfully wrote %" TCL_SIZE_MODIFIER "d bytes of data", ret);
    }

    if (ret != -1 || (ret == -1 && tclErrno == EAGAIN)) {
	if (BIO_should_read(bio)) {
	    dprintf("Setting should retry read flag");

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

/* Called by SSL_read()*/
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);

	if (tclErrno == EAGAIN) {
	    dprintf("It's EAGAIN");
	} else {
	    dprintf("It's an unexpected error: %s/%i", Tcl_ErrnoMsg(tclErrno), tclErrno);
	}

    } else {
	dprintf("Successfully read some data");
	dprintf("Successfully read %" TCL_SIZE_MODIFIER "d bytes of data", ret);
    }

    if (ret != -1 || (ret == -1 && tclErrno == EAGAIN)) {
	if (BIO_should_write(bio)) {
	    dprintf("Setting should retry write flag");

	    BIO_set_retry_write(bio);
	}
    }

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

    return((int) ret);
}

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

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

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);

	if (handshakeFailureIsPermanent) {
	    dprintf("Asked to wait for a TLS handshake that has already failed.  Returning fatal error");
	    *errorCodePtr = ECONNABORTED;
	} else {
	    dprintf("Asked to wait for a TLS handshake that has already failed.  Returning soft error");
	    *errorCodePtr = ECONNRESET;
	}
	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);
	}

	if (err > 0) {
	    dprintf("That seems to have gone okay");
	    dprintf("Accept or connect was successful");

	    err = BIO_flush(statePtr->bio);
	    if (err <= 0) {
		dprintf("Flushing the lower layers failed, this will probably terminate this session");
	    }
	} else {
	    dprintf("Accept or connect failed");
	}

	rc = SSL_get_error(statePtr->ssl, err);

	dprintf("Got error: %i (rc = %i)", err, rc);
	dprintf("Got error: %s", ERR_reason_error_string(ERR_get_error()));
	backingError = ERR_get_error();
	if (rc != SSL_ERROR_NONE) {
	    dprintf("Got error: %i (rc = %i)", err, rc);
	    dprintf("Got error: %s", GET_ERR_REASON());
	}

	bioShouldRetry = 0;
	if (err <= 0) {
	    if (rc == SSL_ERROR_WANT_CONNECT || rc == SSL_ERROR_WANT_ACCEPT || rc == SSL_ERROR_WANT_READ || rc == SSL_ERROR_WANT_WRITE) {
		bioShouldRetry = 1;
	    } else if (BIO_should_retry(statePtr->bio)) {
		bioShouldRetry = 1;

	dprintf("We have either completely established the session or completely failed it -- there is no more need to ever retry it though");
	break;
    }

    switch (rc) {
	case SSL_ERROR_NONE:
	    /* The connection is up, we are done here */
	    dprintf("The connection is up");
	    /* The TLS/SSL I/O operation completed */
	    dprintf("The connection is good");
	    *errorCodePtr = 0;
	    break;

	case SSL_ERROR_ZERO_RETURN:
	    /* The TLS/SSL peer has closed the connection for writing by sending the close_notify alert */
	    dprintf("SSL_ERROR_ZERO_RETURN: Connect returned an invalid value...");
	    *errorCodePtr = EINVAL;
	    Tls_Error(statePtr, "Peer has closed the connection for writing by sending the close_notify alert");
	    return(-1);

	case SSL_ERROR_SYSCALL:
	    backingError = ERR_get_error();
	    /* Some non-recoverable, fatal I/O error occurred */
	    dprintf("SSL_ERROR_SYSCALL");

	    if (backingError == 0 && err == 0) {
		dprintf("EOF reached")
		*errorCodePtr = ECONNRESET;
		Tls_Error(statePtr, "(unexpected) EOF reached");

	    } else if (backingError == 0 && err == -1) {
		dprintf("I/O error occurred (errno = %lu)", (unsigned long) Tcl_GetErrno());
		*errorCodePtr = Tcl_GetErrno();
		if (*errorCodePtr == ECONNRESET) {
		    *errorCodePtr = ECONNABORTED;
		}
		Tls_Error(statePtr, Tcl_ErrnoMsg(Tcl_GetErrno()));

	    } else {
		dprintf("I/O error occurred (backingError = %lu)", backingError);
		*errorCodePtr = backingError;
		if (*errorCodePtr == ECONNRESET) {
		    *errorCodePtr = ECONNABORTED;
		}
		Tls_Error(statePtr, ERR_reason_error_string(backingError));
	    }

	    statePtr->flags |= TLS_TCL_HANDSHAKE_FAILED;
	    return(-1);

	case SSL_ERROR_SSL:
	    /* A non-recoverable, fatal error in the SSL library occurred, usually a protocol error */
	    dprintf("Got permanent fatal SSL error, aborting immediately");
	    Tls_Error(statePtr, (char *)ERR_reason_error_string(ERR_get_error()));
	    dprintf("SSL_ERROR_SSL: Got permanent fatal SSL error, aborting immediately");
	    if (backingError != 0) {
		Tls_Error(statePtr, ERR_reason_error_string(backingError));
	    }
	    if (SSL_get_verify_result(statePtr->ssl) != X509_V_OK) {
		Tls_Error(statePtr, X509_verify_cert_error_string(SSL_get_verify_result(statePtr->ssl)));
	    }
	    statePtr->flags |= TLS_TCL_HANDSHAKE_FAILED;
	    *errorCodePtr = ECONNABORTED;
	    return(-1);

	case SSL_ERROR_WANT_CONNECT:
	case SSL_ERROR_WANT_ACCEPT:
	case SSL_ERROR_WANT_X509_LOOKUP:
	case SSL_ERROR_WANT_ASYNC:
	case SSL_ERROR_WANT_ASYNC_JOB:
	case SSL_ERROR_WANT_CLIENT_HELLO_CB:
	default:
	    /* The operation did not complete and can be retried later. */
	    dprintf("We got a confusing reply: %i", rc);
	    *errorCodePtr = Tcl_GetErrno();
	    dprintf("Operation did not complete, call function again later: %i", rc);
	    *errorCodePtr = EAGAIN;
	    dprintf("ERR(%d, %d) ", rc, *errorCodePtr);
	    return(-1);
    }

	    Tls_Error(statePtr, "Operation did not complete, call function again later");
#if 0
    if (statePtr->flags & TLS_TCL_SERVER) {
	dprintf("This is an TLS server, checking the certificate for the peer");

	err = SSL_get_verify_result(statePtr->ssl);
	if (err != X509_V_OK) {
	    dprintf("Invalid certificate, returning in failure");

	    Tls_Error(statePtr, (char *)X509_verify_cert_error_string(err));
	    statePtr->flags |= TLS_TCL_HANDSHAKE_FAILED;
	    *errorCodePtr = ECONNABORTED;
	    return(-1);
	}
    }
    }
#endif

    dprintf("Removing the \"TLS_TCL_INIT\" flag since we have completed the handshake");
    statePtr->flags &= ~TLS_TCL_INIT;

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

     * correctly.  Similar fix in TlsOutputProc. - hobbs
     */
    ERR_clear_error();
    bytesRead = BIO_read(statePtr->bio, buf, bufSize);
    dprintf("BIO_read -> %d", bytesRead);

    err = SSL_get_error(statePtr->ssl, bytesRead);
    backingError = ERR_get_error();

#if 0
    if (bytesRead <= 0) {
	if (BIO_should_retry(statePtr->bio)) {
	    dprintf("I/O failed, will retry based on EAGAIN");
	    *errorCodePtr = EAGAIN;
	}
    }
#endif

    switch (err) {
	case SSL_ERROR_NONE:
	    dprintBuffer(buf, bytesRead);
	    break;

	case SSL_ERROR_SSL:
	    /* A non-recoverable, fatal error in the SSL library occurred, usually a protocol error */
	    dprintf("SSL negotiation error, indicating that the connection has been aborted");

	    dprintf("SSL error, indicating that the connection has been aborted");
	    if (backingError != 0) {
		Tls_Error(statePtr, ERR_reason_error_string(backingError));
	    }
	    Tls_Error(statePtr, TCLTLS_SSL_ERROR(statePtr->ssl, bytesRead));
	    *errorCodePtr = ECONNABORTED;
	    bytesRead = -1;
	    break;

	case SSL_ERROR_SYSCALL:
	    backingError = ERR_get_error();
	    /* Some non-recoverable, fatal I/O error occurred */

	    if (backingError == 0 && bytesRead == 0) {
		/* Unexpected EOF from the peer for OpenSSL 1.1 */
		dprintf("EOF reached")
		dprintf("(Unexpected) EOF reached")
		*errorCodePtr = 0;
		bytesRead = 0;
		Tls_Error(statePtr, "EOF reached");

	    } else if (backingError == 0 && bytesRead == -1) {
		dprintf("I/O error occurred (errno = %lu)", (unsigned long) Tcl_GetErrno());
		*errorCodePtr = Tcl_GetErrno();
		bytesRead = -1;
		Tls_Error(statePtr, Tcl_ErrnoMsg(Tcl_GetErrno()));

	    } else {
		dprintf("I/O error occurred (backingError = %lu)", backingError);
		*errorCodePtr = backingError;
		bytesRead = -1;
		Tls_Error(statePtr, ERR_reason_error_string(backingError));
	    }
	    break;

	case SSL_ERROR_ZERO_RETURN:
	    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_READ:
	    dprintf("Got SSL_ERROR_WANT_READ, mapping this to EAGAIN");
	    bytesRead = -1;
	    *errorCodePtr = EAGAIN;
	    Tls_Error(statePtr, "SSL_ERROR_WANT_READ");
	    break;

	default:
	    dprintf("Unknown error (err = %i), mapping to EOF", err);
	    *errorCodePtr = 0;
	    bytesRead = 0;
	    break;

     * work correctly.  Similar fix in TlsInputProc. - hobbs
     */
    ERR_clear_error();
    written = BIO_write(statePtr->bio, buf, toWrite);
    dprintf("BIO_write(%p, %d) -> [%d]", (void *) statePtr, toWrite, written);

    err = SSL_get_error(statePtr->ssl, written);
    backingError = ERR_get_error();

    switch (err) {
	case SSL_ERROR_NONE:
	    if (written < 0) {
		written = 0;
	    }
	    break;

	case SSL_ERROR_WANT_WRITE:
	    dprintf("Got SSL_ERROR_WANT_WRITE, mapping it to EAGAIN");
	    *errorCodePtr = EAGAIN;
	    written = -1;
	    Tls_Error(statePtr, "SSL_ERROR_WANT_WRITE");
	    break;

	case SSL_ERROR_WANT_READ:
	    dprintf(" write R BLOCK");
	    Tls_Error(statePtr, "SSL_ERROR_WANT_READ");
	    break;

	case SSL_ERROR_WANT_X509_LOOKUP:
	    dprintf(" write X BLOCK");
	    Tls_Error(statePtr, "SSL_ERROR_WANT_X509_LOOKUP");
	    break;

	case SSL_ERROR_ZERO_RETURN:
	    dprintf(" closed");
	    written = 0;
	    *errorCodePtr = 0;
	    Tls_Error(statePtr, "Peer has closed the connection for writing by sending the close_notify alert");
	    break;

	case SSL_ERROR_SYSCALL:
	    backingError = ERR_get_error();
	    /* Some non-recoverable, fatal I/O error occurred */

	    if (backingError == 0 && written == 0) {
		dprintf("EOF reached")
		*errorCodePtr = 0;
		written = 0;
		Tls_Error(statePtr, "EOF reached");

	    } else if (backingError == 0 && written == -1) {
		dprintf("I/O error occurred (errno = %lu)", (unsigned long) Tcl_GetErrno());
		*errorCodePtr = Tcl_GetErrno();
		written = -1;
		Tls_Error(statePtr, Tcl_ErrnoMsg(Tcl_GetErrno()));

	    } else {
		dprintf("I/O error occurred (backingError = %lu)", backingError);
		*errorCodePtr = backingError;
		written = -1;
		Tls_Error(statePtr, ERR_reason_error_string(backingError));
	    }
	    break;

	case SSL_ERROR_SSL:
	    /* A non-recoverable, fatal error in the SSL library occurred, usually a protocol error */
	    dprintf("SSL error, indicating that the connection has been aborted");
	    if (backingError != 0) {
	    Tls_Error(statePtr, TCLTLS_SSL_ERROR(statePtr->ssl, written));
		Tls_Error(statePtr, ERR_reason_error_string(backingError));
	    }
	    *errorCodePtr = ECONNABORTED;
	    written = -1;
	    break;

	default:
	    dprintf(" unknown err: %d", err);
	    dprintf("unknown error: %d", err);
	    break;
    }

    if (*errorCodePtr < 0) {
	Tls_Error(statePtr, strerror(*errorCodePtr));
    }
    dprintf("Output(%d) -> %d", toWrite, written);

}
#else
#define dprintf(...) if (0) { fprintf(stderr, __VA_ARGS__); }
#define dprintBuffer(bufferName, bufferLength) /**/
#define dprintFlags(statePtr) /**/
#endif

#define TCLTLS_SSL_ERROR(ssl,err) ((char*)ERR_reason_error_string((unsigned long)SSL_get_error((ssl),(err))))
#define GET_ERR_REASON()	ERR_reason_error_string(ERR_get_error())

/* Common list append macros */
#define LAPPEND_BARRAY(interp, obj, text, value, size) {\
    if (text != NULL) Tcl_ListObjAppendElement(interp, obj, Tcl_NewStringObj(text, -1)); \
    Tcl_ListObjAppendElement(interp, obj, Tcl_NewByteArrayObj(value, size)); \
}