*    SSLtcl (Peter Antman)
 *
 */

#include "tlsInt.h"
#include <errno.h>

/*
 * Forward declarations
 */
static void TlsChannelHandlerTimer(ClientData clientData);

/*
 *-------------------------------------------------------------------
 *
 * TlsBlockModeProc --
 *
 *    This procedure is invoked by the generic IO level
 *       to set blocking and nonblocking modes
 *       to set channel to blocking or nonblocking mode.
 *
 * Results:
 *    0 if successful or POSIX error code if failed.
 *
 * Side effects:
 *    Sets the device into blocking or nonblocking mode.
 *

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

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

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

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

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

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

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

    if (!(statePtr->flags & TLS_TCL_INIT)) {

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

	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) {
	    if (rc == SSL_ERROR_WANT_CONNECT || rc == SSL_ERROR_WANT_ACCEPT) {
		bioShouldRetry = 1;
	    } else if (rc == SSL_ERROR_WANT_READ) {
		bioShouldRetry = 1;
		statePtr->want = TCL_READABLE;
	    } else if (rc == SSL_ERROR_WANT_WRITE) {
		bioShouldRetry = 1;
		statePtr->want = TCL_WRITABLE;
	    } else if (BIO_should_retry(statePtr->bio)) {
		bioShouldRetry = 1;
	    } else if (rc == SSL_ERROR_SYSCALL && Tcl_GetErrno() == EAGAIN) {
		bioShouldRetry = 1;
	    }
	} else {
	    if (!SSL_is_init_finished(statePtr->ssl)) {

    switch (rc) {
	case SSL_ERROR_NONE:
	    /* 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;
	case SSL_ERROR_SSL:
	    /* A non-recoverable, fatal error in the SSL library occurred, usually a protocol error */
	    dprintf("SSL_ERROR_SSL: Got permanent fatal SSL error, aborting immediately");
	    if (SSL_get_verify_result(statePtr->ssl) != X509_V_OK) {
		Tls_Error(statePtr, X509_verify_cert_error_string(SSL_get_verify_result(statePtr->ssl)));
	    }
	    if (backingError != 0) {
		Tls_Error(statePtr, ERR_reason_error_string(backingError));
	    }
	    statePtr->flags |= TLS_TCL_HANDSHAKE_FAILED;
	    *errorCodePtr = ECONNABORTED;
	    Tls_Error(statePtr, "Peer has closed the connection for writing by sending the close_notify alert");
	    return -1;

	case SSL_ERROR_SYSCALL:
	    /* 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, (char *) Tcl_ErrnoMsg(*errorCodePtr));
		Tls_Error(statePtr, Tcl_ErrnoMsg(*errorCodePtr));

	    } else {
		dprintf("I/O error occurred (backingError = %lu)", backingError);
		*errorCodePtr = Tcl_GetErrno();
		if (*errorCodePtr == ECONNRESET) {
		    *errorCodePtr = ECONNABORTED;
		}
		Tls_Error(statePtr, (char *) ERR_reason_error_string(backingError));
		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("SSL_ERROR_SSL: Got permanent fatal SSL error, aborting immediately");
	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...");
	    if (SSL_get_verify_result(statePtr->ssl) != X509_V_OK) {
		Tls_Error(statePtr, (char *) X509_verify_cert_error_string(SSL_get_verify_result(statePtr->ssl)));
	    }
	    if (backingError != 0) {
		Tls_Error(statePtr, (char *) ERR_reason_error_string(backingError));
	    }
	    statePtr->flags |= TLS_TCL_HANDSHAKE_FAILED;
	    *errorCodePtr = ECONNABORTED;
	    *errorCodePtr = EINVAL;
	    Tls_Error(statePtr, "Peer has closed the connection for writing by sending the close_notify alert");
	    return -1;

	case SSL_ERROR_WANT_READ:
	case SSL_ERROR_WANT_WRITE:
	case SSL_ERROR_WANT_X509_LOOKUP:
	case SSL_ERROR_WANT_CONNECT:
	case SSL_ERROR_WANT_ACCEPT:
	case SSL_ERROR_WANT_ASYNC:
	case SSL_ERROR_WANT_ASYNC_JOB:
	case SSL_ERROR_WANT_CLIENT_HELLO_CB:
#if OPENSSL_VERSION_NUMBER >= 0x30000000L
	case SSL_ERROR_WANT_RETRY_VERIFY:
#endif
	default:
	    /* The operation did not complete and should be retried later. */
	    dprintf("Operation did not complete, call function again later: %i", rc);
	    *errorCodePtr = EAGAIN;
	    dprintf("ERR(%d, %d) ", rc, *errorCodePtr);
	    Tls_Error(statePtr, "Operation did not complete, call function again later");
	    return -1;

 *    Reads input from the input device of the channel.
 *
 *-------------------------------------------------------------------
 */
static int TlsInputProc(ClientData instanceData, char *buf, int bufSize, int *errorCodePtr) {
    unsigned long backingError;
    State *statePtr = (State *) instanceData;
    int bytesRead;
    int bytesRead, err;
    int tlsConnect;
    int err;

    *errorCodePtr = 0;

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

    /* Skip if user verify callback is still running */
    if (statePtr->flags & TLS_TCL_CALLBACK) {
	/* don't process any bytes while verify callback is running */
	dprintf("Callback is running, reading 0 bytes");
	return 0;
    }

    /* If not initialized, do connect */
    if (statePtr->flags & TLS_TCL_INIT) {
	int tlsConnect;

    dprintf("Calling Tls_WaitForConnect");
    tlsConnect = Tls_WaitForConnect(statePtr, errorCodePtr, 0);
    if (tlsConnect < 0) {
	dprintf("Got an error waiting to connect (tlsConnect = %i, *errorCodePtr = %i)", tlsConnect, *errorCodePtr);
	Tls_Error(statePtr, strerror(*errorCodePtr));
	dprintf("Calling Tls_WaitForConnect");

	tlsConnect = Tls_WaitForConnect(statePtr, errorCodePtr, 0);
	if (tlsConnect < 0) {
	    dprintf("Got an error waiting to connect (tlsConnect = %i, *errorCodePtr = %i)", tlsConnect, *errorCodePtr);
	    Tls_Error(statePtr, strerror(*errorCodePtr));

	bytesRead = -1;
	if (*errorCodePtr == ECONNRESET) {
	    dprintf("Got connection reset");
	    /* Soft EOF */
	    *errorCodePtr = 0;
	    bytesRead = 0;
	}
	return bytesRead;
	    bytesRead = -1;
	    if (*errorCodePtr == ECONNRESET) {
		dprintf("Got connection reset");
		/* Soft EOF */
		*errorCodePtr = 0;
		bytesRead = 0;
	    }
	    return bytesRead;
	}
    }

    /*
     * We need to clear the SSL error stack now because we sometimes reach
     * this function with leftover errors in the stack.  If BIO_read
     * returns -1 and intends EAGAIN, there is a leftover error, it will be
     * misconstrued as an error, not EAGAIN.
     *
     * Alternatively, we may want to handle the <0 return codes from
     * BIO_read specially (as advised in the RSA docs).  TLS's lower level BIO
     * functions play with the retry flags though, and this seems to work
     * correctly.  Similar fix in TlsOutputProc. - hobbs
     */
    ERR_clear_error();
    /* BIO_read, where 0 means EOF and -1 means error */
    bytesRead = BIO_read(statePtr->bio, buf, bufSize);
    dprintf("BIO_read -> %d", bytesRead);

    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;
	    dprintf("Read failed with code=%d, bytes read=%d: should retry", err, bytesRead);
	    /* Some docs imply we should redo the BIO_read now */
	} else {
	    dprintf("Read failed with code=%d, bytes read=%d: error condition", err, bytesRead);
	}
	
	/* These are the same as BIO_retry_type */
	if (BIO_should_read(statePtr->bio)) {
	    dprintf("BIO has insufficient data to read and return");
	}
	if (BIO_should_write(statePtr->bio)) {
	    dprintf("BIO has pending data to write");
    }
#endif
	}
	if (BIO_should_io_special(statePtr->bio)) {
	    int reason = BIO_get_retry_reason(statePtr->bio);
	    dprintf("BIO has some special condition other than read or write: code=%d", reason);
	}
	dprintf("BIO has pending data to write");
    }

    switch (err) {
	case SSL_ERROR_NONE:
	    /* I/O operation completed */
	    dprintf("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 error, indicating that the connection has been aborted");
	    if (backingError != 0) {
		Tls_Error(statePtr, (char *) ERR_reason_error_string(backingError));
		Tls_Error(statePtr, ERR_reason_error_string(backingError));
	    } else if (SSL_get_verify_result(statePtr->ssl) != X509_V_OK) {
		Tls_Error(statePtr, (char *) X509_verify_cert_error_string(SSL_get_verify_result(statePtr->ssl)));
		Tls_Error(statePtr, X509_verify_cert_error_string(SSL_get_verify_result(statePtr->ssl)));
	    } else {
		Tls_Error(statePtr, "Unknown SSL error");
	    }
	    *errorCodePtr = ECONNABORTED;
	    bytesRead = -1;

#if OPENSSL_VERSION_NUMBER >= 0x30000000L
	    /* Unexpected EOF from the peer for OpenSSL 3.0+ */
	    if (ERR_GET_REASON(backingError) == SSL_R_UNEXPECTED_EOF_WHILE_READING) {
		dprintf("(Unexpected) EOF reached")
		*errorCodePtr = 0;
		bytesRead = 0;
		Tls_Error(statePtr, "EOF reached");
	    }    
	    }
#endif
	    break;

	case SSL_ERROR_WANT_READ:
	    /* Op did not complete due to not enough data was available. Retry later. */
	    dprintf("Got SSL_ERROR_WANT_READ, mapping this to EAGAIN");
	    *errorCodePtr = EAGAIN;
	    bytesRead = -1;
	    statePtr->want = TCL_READABLE;
	    Tls_Error(statePtr, "SSL_ERROR_WANT_READ");
	    break;

	case SSL_ERROR_WANT_WRITE:
	    /* Op did not complete due to unable to sent all data to the BIO. Retry later. */
	    dprintf("Got SSL_ERROR_WANT_WRITE, mapping this to EAGAIN");
	    *errorCodePtr = EAGAIN;
	    bytesRead = -1;
	    statePtr->want = TCL_WRITABLE;
	    Tls_Error(statePtr, "SSL_ERROR_WANT_WRITE");
	    break;

	case SSL_ERROR_WANT_X509_LOOKUP:
	    /* Op didn't complete since callback set by SSL_CTX_set_client_cert_cb() asked to be called again */
	    dprintf("Got SSL_ERROR_WANT_X509_LOOKUP, mapping it to EAGAIN");
	    *errorCodePtr = EAGAIN;
	    bytesRead = -1;
	    Tls_Error(statePtr, "SSL_ERROR_WANT_X509_LOOKUP");
	    break;

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

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

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

	case SSL_ERROR_ZERO_RETURN:
	    /* Peer has closed the connection for writing by sending the close_notify alert. No more data can be read. */
	    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");
	case SSL_ERROR_WANT_ASYNC:
	    /* Used with flag SSL_MODE_ASYNC, op didn't complete because an async engine is still processing data */
	    dprintf("Got SSL_ERROR_WANT_ASYNC, mapping this to EAGAIN");
	    bytesRead = -1;
	    *errorCodePtr = EAGAIN;
	    Tls_Error(statePtr, "SSL_ERROR_WANT_READ");
	    Tls_Error(statePtr, "SSL_ERROR_WANT_ASYNC");
	    break;

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

 *
 *-------------------------------------------------------------------
 */
static int TlsOutputProc(ClientData instanceData, const char *buf, int toWrite, int *errorCodePtr) {
    unsigned long backingError;
    State *statePtr = (State *) instanceData;
    int written, err;
    int tlsConnect;

    *errorCodePtr = 0;

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

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

    /* If not initialized, do connect */
    if (statePtr->flags & TLS_TCL_INIT) {
	int tlsConnect;

    dprintf("Calling Tls_WaitForConnect");
    tlsConnect = Tls_WaitForConnect(statePtr, errorCodePtr, 1);
    if (tlsConnect < 0) {
	dprintf("Got an error waiting to connect (tlsConnect = %i, *errorCodePtr = %i)", tlsConnect, *errorCodePtr);
	Tls_Error(statePtr, strerror(*errorCodePtr));
	dprintf("Calling Tls_WaitForConnect");

	tlsConnect = Tls_WaitForConnect(statePtr, errorCodePtr, 1);
	if (tlsConnect < 0) {
	    dprintf("Got an error waiting to connect (tlsConnect = %i, *errorCodePtr = %i)", tlsConnect, *errorCodePtr);
	    Tls_Error(statePtr, strerror(*errorCodePtr));

	written = -1;
	if (*errorCodePtr == ECONNRESET) {
	    dprintf("Got connection reset");
	    /* Soft EOF */
	    *errorCodePtr = 0;
	    written = 0;
	}
	return written;
	    written = -1;
	    if (*errorCodePtr == ECONNRESET) {
		dprintf("Got connection reset");
		/* Soft EOF */
		*errorCodePtr = 0;
		written = 0;
	    }
	    return written;
	}
    }

    if (toWrite == 0) {
	dprintf("zero-write");
	err = BIO_flush(statePtr->bio);

	if (err <= 0) {

     *
     * Alternatively, we may want to handle the <0 return codes from
     * BIO_write specially (as advised in the RSA docs).  TLS's lower level
     * BIO functions play with the retry flags though, and this seems to
     * work correctly.  Similar fix in TlsInputProc. - hobbs
     */
    ERR_clear_error();
    /* SSL_write will return 1 for success or 0 for failure */
    written = BIO_write(statePtr->bio, buf, toWrite);
    dprintf("BIO_write(%p, %d) -> [%d]", (void *) statePtr, toWrite, written);

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

    if (written <= 0) {
	if (BIO_should_retry(statePtr->bio)) {
	    dprintf("Write failed with code %d, bytes written=%d: should retry", err, written);
	} else {
	    dprintf("Write failed with code %d, bytes written=%d: error condition", err, written);
	}
	
	/* These are the same as BIO_retry_type */
	if (BIO_should_read(statePtr->bio)) {
	    dprintf("BIO has insufficient data to read and return");
	}
	if (BIO_should_write(statePtr->bio)) {
	    dprintf("BIO has pending data to write");
	}
	if (BIO_should_io_special(statePtr->bio)) {
	    int reason = BIO_get_retry_reason(statePtr->bio);
	    dprintf("BIO has some special condition other than read or write: code=%d", reason);
	}
	dprintf("BIO has pending data to write");

    } else {
	BIO_flush(statePtr->bio);
    }

    switch (err) {
	case SSL_ERROR_NONE:
	    /* I/O operation completed */
	    dprintf("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;
	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, ERR_reason_error_string(backingError));
	    } else if (SSL_get_verify_result(statePtr->ssl) != X509_V_OK) {
		Tls_Error(statePtr, X509_verify_cert_error_string(SSL_get_verify_result(statePtr->ssl)));
	    } else {
		Tls_Error(statePtr, "Unknown SSL error");
	    }
	    *errorCodePtr = ECONNABORTED;
	    written = -1;
	    Tls_Error(statePtr, "SSL_ERROR_WANT_WRITE");
	    break;

	case SSL_ERROR_WANT_READ:
	    /* Op did not complete due to not enough data was available. Retry later. */
	    dprintf("Got SSL_ERROR_WANT_READ, mapping it to EAGAIN");
	    *errorCodePtr = EAGAIN;
	    written = -1;
	    statePtr->want = TCL_READABLE;
	    Tls_Error(statePtr, "SSL_ERROR_WANT_READ");
	    break;
	    dprintf(" write R BLOCK");
	    Tls_Error(statePtr, "SSL_ERROR_WANT_READ");

	case SSL_ERROR_WANT_WRITE:
	    /* Op did not complete due to unable to sent all data to the BIO. Retry later. */
	    dprintf("Got SSL_ERROR_WANT_WRITE, mapping it to EAGAIN");
	    *errorCodePtr = EAGAIN;
	    written = -1;
	    statePtr->want = TCL_WRITABLE;
	    Tls_Error(statePtr, "SSL_ERROR_WANT_WRITE");
	    break;

	case SSL_ERROR_WANT_X509_LOOKUP:
	    /* Op didn't complete since callback set by SSL_CTX_set_client_cert_cb() asked to be called again */
	    dprintf("Got SSL_ERROR_WANT_X509_LOOKUP, mapping it to EAGAIN");
	    *errorCodePtr = EAGAIN;
	    dprintf(" write X BLOCK");
	    written = -1;
	    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:
	    /* Some non-recoverable, fatal I/O error occurred */
	    dprintf("SSL_ERROR_SYSCALL");

	    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, (char *) Tcl_ErrnoMsg(*errorCodePtr));
		Tls_Error(statePtr, Tcl_ErrnoMsg(*errorCodePtr));

	    } else {
		dprintf("I/O error occurred (backingError = %lu)", backingError);
		*errorCodePtr = Tcl_GetErrno();
		written = -1;
		Tls_Error(statePtr, (char *) ERR_reason_error_string(backingError));
		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, (char *) ERR_reason_error_string(backingError));
	case SSL_ERROR_ZERO_RETURN:
	    /* Peer has closed the connection for writing by sending the close_notify alert. No more data can be read. */
	    dprintf(" closed");
	    written = 0;
	    *errorCodePtr = 0;
	    } else if (SSL_get_verify_result(statePtr->ssl) != X509_V_OK) {
		Tls_Error(statePtr, (char *) X509_verify_cert_error_string(SSL_get_verify_result(statePtr->ssl)));
	    } else {
		Tls_Error(statePtr, "Unknown SSL error");
	    }
	    *errorCodePtr = ECONNABORTED;
	    Tls_Error(statePtr, "Peer has closed the connection for writing by sending the close_notify alert");
	    break;

	case SSL_ERROR_WANT_ASYNC:
	    /* Used with flag SSL_MODE_ASYNC, op didn't complete because an async engine is still processing data */
	    dprintf("Got SSL_ERROR_WANT_ASYNC, mapping this to EAGAIN");
	    *errorCodePtr = EAGAIN;
	    written = -1;
	    Tls_Error(statePtr, "SSL_ERROR_WANT_ASYNC");
	    break;

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

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

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

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

/*
 *-------------------------------------------------------------------
 *
 * TlsSetOptionProc --
 *
 *    Sets an option value for a SSL socket based channel, or a
 *    Sets an option value for a SSL socket based channel.
 *    list of all options and their values.
 *
 * Results:
 *    TCL_OK if successful or TCL_ERROR if failed.
 *
 * Side effects:
 *    Updates channel option to new value.
 *
 *-------------------------------------------------------------------
 */
static int
TlsSetOptionProc(ClientData instanceData,    /* Socket state. */
    Tcl_Interp *interp,		/* For errors - can be NULL. */
    const char *optionName,	/* Name of the option to set the value for, or
				 * NULL to get all options and their values. */
    const char *optionValue)	/* Value for option. */
{
    State *statePtr = (State *) instanceData;

    Tcl_Channel downChan = Tls_GetParent(statePtr, TLS_TCL_FASTPATH);
    Tcl_DriverSetOptionProc *setOptionProc;

    dprintf("Called");

    setOptionProc = Tcl_ChannelSetOptionProc(Tcl_GetChannelType(downChan));
    if (setOptionProc != NULL) {
	return (*setOptionProc)(Tcl_GetChannelInstanceData(downChan), interp, optionName, optionValue);
    } else if (optionName == (char*) NULL) {
	/*
	 * Request is query for all options, this is ok.
	 */
	return TCL_OK;
    }
    /*
     * Request for a specific option has to fail, we don't have any.
     */
    return Tcl_BadChannelOption(interp, optionName, "");
}

TlsGetOptionProc(ClientData instanceData,    /* Socket state. */
    Tcl_Interp *interp,		/* For errors - can be NULL. */
    const char *optionName,	/* Name of the option to retrieve the value for, or
				 * NULL to get all options and their values. */
    Tcl_DString *optionValue)	/* Where to store the computed value initialized by caller. */
{
    State *statePtr = (State *) instanceData;

    Tcl_Channel downChan = Tls_GetParent(statePtr, TLS_TCL_FASTPATH);
    Tcl_DriverGetOptionProc *getOptionProc;

    dprintf("Called");

    getOptionProc = Tcl_ChannelGetOptionProc(Tcl_GetChannelType(downChan));
    if (getOptionProc != NULL) {
	return (*getOptionProc)(Tcl_GetChannelInstanceData(downChan), interp, optionName, optionValue);
    } else if (optionName == (char*) NULL) {
	/*
	 * Request is query for all options, this is ok.
	 */
	return TCL_OK;
    }
    /*
     * Request for a specific option has to fail, we don't have any.
     */
    return Tcl_BadChannelOption(interp, optionName, "");
}

/*
 *------------------------------------------------------*
 *
 *    TlsChannelHandlerTimer --
 *
 *    ------------------------------------------------*
 *    Called by the notifier (-> timer) to flush out
 *    information waiting in channel buffers.
 *    ------------------------------------------------*
 *
 *    Side effects:
 *        As of 'TlsChannelHandler'.
 *
 *    Result:
 *        None.
 *
 *------------------------------------------------------*
 */
static void TlsChannelHandlerTimer(ClientData clientData) {
    State *statePtr = (State *) clientData;
    int mask = statePtr->want; /* Init to SSL_ERROR_WANT_READ and SSL_ERROR_WANT_WRITE */

    dprintf("Called");

    statePtr->timer = (Tcl_TimerToken) NULL;

    if (BIO_wpending(statePtr->bio)) {
	dprintf("[chan=%p] BIO writable", statePtr->self);

	mask |= TCL_WRITABLE;
    }

    if (BIO_pending(statePtr->bio)) {
	dprintf("[chan=%p] BIO readable", statePtr->self);

	mask |= TCL_READABLE;
    }

    dprintf("Notifying ourselves");
    Tcl_NotifyChannel(statePtr->self, mask);
    statePtr->want = 0;

    dprintf("Returning");

    return;
}

/*
 *-------------------------------------------------------------------
 *
 * TlsWatchProc --
 *
 *    Initialize the event notifier to watch for events of interest
 *    Initialize the notifier to watch Tcl_Files from this channel.
 *    from this channel.
 *
 * Results:
 *    None.
 *
 * Side effects:
 *    Sets up the notifier so that a future event on the channel
 *    will be seen by Tcl.
 *
 *-------------------------------------------------------------------
 */
static void
TlsWatchProc(ClientData instanceData,    /* The socket state. */
    int mask)			/* Events of interest; an OR-ed combination of
				 * TCL_READABLE, TCL_WRITABLE and TCL_EXCEPTION. */
{
    Tcl_Channel     downChan;
    State *statePtr = (State *) instanceData;
    Tcl_DriverWatchProc *watchProc;

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

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

    dprintFlags(statePtr);

    downChan = Tls_GetParent(statePtr, TLS_TCL_FASTPATH);

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

	watchProc = Tcl_ChannelWatchProc(Tcl_GetChannelType(downChan));

     */
    if (statePtr->timer != (Tcl_TimerToken) NULL) {
	dprintf("A timer was found, deleting it");
	Tcl_DeleteTimerHandler(statePtr->timer);
	statePtr->timer = (Tcl_TimerToken) NULL;
    }

    if ((mask & TCL_READABLE) &&
	((Tcl_InputBuffered(statePtr->self) > 0) || (BIO_ctrl_pending(statePtr->bio) > 0))) {
    if (statePtr->want || ((mask & TCL_READABLE) &&
	((Tcl_InputBuffered(statePtr->self) > 0) || (BIO_ctrl_pending(statePtr->bio) > 0)))) {
	/*
	 * There is interest in readable events and we actually have
	 * data waiting, so generate a timer to flush that.
	 */
	dprintf("Creating a new timer since data appears to be waiting");
	statePtr->timer = Tcl_CreateTimerHandler(TLS_TCL_DELAY, TlsChannelHandlerTimer, (ClientData) statePtr);
    }
}

/*
 *-------------------------------------------------------------------
 *
 * TlsGetHandleProc --
 *
 *    Called from Tcl_GetChannelFile to retrieve o/s file handler
 *    from the SSL socket based channel.
 *    This procedure is invoked by the generic IO level to retrieve a
 *    device-specific handle from the SSL socket based channel.
 *
 * Results:
 *    The appropriate Tcl_File handle or NULL if none.
 *
 * Side effects:
 *    None.
 *

}

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

    dprintf("Called");

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

    /* Skip if user verify callback is still running */
    if (statePtr->flags & TLS_TCL_CALLBACK) {
	dprintf("Returning 0 due to callback");
	dprintf("Callback is on-going, returning failed");
	return 0;
    }

    /* If not initialized, do connect */
    if (statePtr->flags & TLS_TCL_INIT) {
    dprintf("Calling Tls_WaitForConnect");
	dprintf("Calling Tls_WaitForConnect");
    errorCode = 0;
    if (Tls_WaitForConnect(statePtr, &errorCode, 1) < 0) {
	Tls_Error(statePtr, strerror(errorCode));
	if (errorCode == EAGAIN) {
	    dprintf("Async flag could be set (didn't check) and errorCode == EAGAIN:  Returning 0");
	if (Tls_WaitForConnect(statePtr, &errorCode, 1) < 0) {
	    Tls_Error(statePtr, strerror(errorCode));
	    if (errorCode == EAGAIN) {
		dprintf("Async flag could be set (didn't check) and errorCode == EAGAIN:  Returning failed");

	    return 0;
	}
		return 0;
	    }

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

    dprintf("Returning %i", mask);

    return mask;
}

/*
 *------------------------------------------------------*
 *
 *    TlsChannelHandlerTimer --
 *
 *    ------------------------------------------------*
 *    Called by the notifier (-> timer) to flush out
 *    information waiting in channel buffers.
 *    ------------------------------------------------*
 *
 *    Side effects:
 *        As of 'TlsChannelHandler'.
 *
 *    Result:
 *        None.
 *
 *------------------------------------------------------*
 */
static void TlsChannelHandlerTimer(ClientData clientData) {
    State *statePtr = (State *) clientData;
    int mask = 0;

    dprintf("Called");

    statePtr->timer = (Tcl_TimerToken) NULL;

    if (BIO_wpending(statePtr->bio)) {
	dprintf("[chan=%p] BIO writable", statePtr->self);

	mask |= TCL_WRITABLE;
    }

    if (BIO_pending(statePtr->bio)) {
	dprintf("[chan=%p] BIO readable", statePtr->self);

	mask |= TCL_READABLE;
    }

    dprintf("Notifying ourselves");
    Tcl_NotifyChannel(statePtr->self, mask);

    dprintf("Returning");

    return;
}

Tcl_Channel Tls_GetParent(State *statePtr, int maskFlags) {
    dprintf("Requested to get parent of channel %p", statePtr->self);

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

/*
 *-------------------------------------------------------------------
 *
 * Tls_ChannelType --
 *
 *    Return the correct TLS channel driver info
 *