/*
 * Copyright (C) 1997-1999 Matt Newman <[email protected]>
 * some modifications:
 *	Copyright (C) 2000 Ajuba Solutions
 *	Copyright (C) 2002 ActiveState Corporation
 *	Copyright (C) 2003 Starfish Systems
 *
 * $Header: /home/rkeene/tmp/cvs2fossil/../tcltls/tls/tls/tls.c,v 1.14 2002/02/04 22:46:31 hobbs Exp $
 * $Header: /home/rkeene/tmp/cvs2fossil/../tcltls/tls/tls/tls.c,v 1.15 2003/05/15 20:44:46 razzell Exp $
 *
 * 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
 *

			Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]));

static int	ImportObjCmd _ANSI_ARGS_ ((ClientData clientData,
			Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]));

static int	StatusObjCmd _ANSI_ARGS_ ((ClientData clientData,
			Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]));

static int	VersionObjCmd _ANSI_ARGS_ ((ClientData clientData,
			Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]));

static SSL_CTX *CTX_Init _ANSI_ARGS_((Tcl_Interp *interp, int proto, char *key,
static SSL_CTX *CTX_Init _ANSI_ARGS_((State *statePtr, int proto, char *key,
			char *cert, char *CAdir, char *CAfile, char *ciphers));

#define TLS_PROTO_SSL2	0x01
#define TLS_PROTO_SSL3	0x02
#define TLS_PROTO_TLS1	0x04
#define ENABLED(flag, mask)	(((flag) & (mask)) == (mask))

	if (where & SSL_CB_READ)		minor = "read";
	else if (where & SSL_CB_WRITE)		minor = "write";
	else if (where & SSL_CB_LOOP)		minor = "loop";
	else if (where & SSL_CB_EXIT)		minor = "exit";
	else					minor = "unknown";
    }


    Tcl_ListObjAppendElement( statePtr->interp, cmdPtr, 
	    Tcl_NewStringObj( "info", -1));

    Tcl_ListObjAppendElement( statePtr->interp, cmdPtr, 
	    Tcl_NewStringObj( Tcl_GetChannelName(statePtr->self), -1) );

    Tcl_ListObjAppendElement( statePtr->interp, cmdPtr,
	    Tcl_NewStringObj( major, -1) );

    Tcl_ListObjAppendElement( statePtr->interp, cmdPtr,
	    Tcl_NewStringObj( minor, -1) );

    if (where & (SSL_CB_LOOP|SSL_CB_EXIT)) {
	Tcl_ListObjAppendElement( statePtr->interp, cmdPtr,
	    Tcl_NewStringObj( SSL_state_string_long(ssl), -1) );
    } else if (where & SSL_CB_ALERT) {
	char *cp = SSL_alert_desc_string_long(ret);
	char *cp = (char *) SSL_alert_desc_string_long(ret);

	Tcl_ListObjAppendElement( statePtr->interp, cmdPtr,
	    Tcl_NewStringObj( cp, -1) );
    } else {
	Tcl_ListObjAppendElement( statePtr->interp, cmdPtr,
	    Tcl_NewStringObj( SSL_state_string_long(ssl), -1) );
    }

}

/*
 *-------------------------------------------------------------------
 *
 * PasswordCallback -- 
 *
 *	Called when a password is needed to unpack RSA and PEM keys
 *	Evals the tcl proc:  tls::password and returns the result as
 *	the password
 *	Called when a password is needed to unpack RSA and PEM keys.
 *	Evals any bound password script and returns the result as
 *	the password string.
 *-------------------------------------------------------------------
 */
#ifdef PRE_OPENSSL_0_9_4
/*
 * No way to handle user-data therefore no way without a global
 * variable to access the Tcl interpreter.
*/
static int
PasswordCallback(char *buf, int size, int verify)
{
    return -1;
}
#else
static int
PasswordCallback(char *buf, int size, int verify, void *udata)
{
    State *statePtr	= (State *) udata;
    Tcl_Interp *interp = (Tcl_Interp*)udata;
    Tcl_Interp *interp	= statePtr->interp;
    Tcl_Obj *cmdPtr;
    int result;

    if (statePtr->password == NULL) {
    if (Tcl_Eval(interp, "tls::password") == TCL_OK) {
	CONST char *ret = Tcl_GetStringResult(interp);
	if (Tcl_Eval(interp, "tls::password") == TCL_OK) {
	    char *ret = (char *) Tcl_GetStringResult(interp);
            strncpy(buf, ret, size);
	    return strlen(ret);
	} else {
	    return -1;
	}
    }

    cmdPtr = Tcl_DuplicateObj(statePtr->password);

    Tcl_Preserve((ClientData) statePtr->interp);
    Tcl_Preserve((ClientData) statePtr);

    Tcl_IncrRefCount(cmdPtr);
    result = Tcl_GlobalEvalObj(interp, cmdPtr);
    if (result != TCL_OK) {
	Tcl_BackgroundError(statePtr->interp);
    }
    Tcl_DecrRefCount(cmdPtr);

    Tcl_Release((ClientData) statePtr);
    Tcl_Release((ClientData) statePtr->interp);

    if (result == TCL_OK) {
	char *ret = (char *) Tcl_GetStringResult(interp);
        strncpy(buf, ret, size);
	return strlen(ret);
    } else {
	return -1;
    }
}
#endif

    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;
    int idx;
    int flags		= TLS_TCL_INIT;
    int server		= 0;	/* is connection incoming or outgoing? */
    char *key		= NULL;
    char *cert		= NULL;
    char *ciphers	= NULL;
    char *CAfile	= NULL;

    for (idx = 2; idx < objc; idx++) {
	char *opt = Tcl_GetStringFromObj(objv[idx], NULL);

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

	OPTSTR( "-cafile", CAfile);
	OPTSTR( "-cadir", CAdir);
	OPTSTR( "-cafile", CAfile);
	OPTSTR( "-certfile", cert);
	OPTSTR( "-cipher", ciphers);
	OPTOBJ( "-command", script);
	OPTSTR( "-keyfile", key);
	OPTSTR( "-model", model);
	OPTOBJ( "-password", password);
	OPTBOOL( "-require", require);
	OPTBOOL( "-request", request);
	OPTBOOL( "-server", server);

	OPTBOOL( "-ssl2", ssl2);
	OPTBOOL( "-ssl3", ssl3);
	OPTBOOL( "-tls1", tls1);

	OPTBAD( "option", "-cafile, -cadir, -certfile, -cipher, -command, -keyfile, -model, -require, -request, -ssl2, -ssl3, -server, or -tls1");
	OPTBAD( "option", "-cadir, -cafile, -certfile, -cipher, -command, -keyfile, -model, -password, -require, -request, -server, -ssl2, -ssl3, or -tls1");

	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 (verify == 0)        verify = SSL_VERIFY_NONE;

    proto |= (ssl2 ? TLS_PROTO_SSL2 : 0);
    proto |= (ssl3 ? TLS_PROTO_SSL3 : 0);
    proto |= (tls1 ? TLS_PROTO_TLS1 : 0);

    /* reset to NULL if blank string provided */
    if (cert && !*cert)		cert	= NULL;
    if (key && !*key)		key	= NULL;
    if (ciphers && !*ciphers)	ciphers	= NULL;
    if (CAfile && !*CAfile)	CAfile	= NULL;
    if (CAdir && !*CAdir)	CAdir	= NULL;

    if (model != NULL) {
	int mode;
	/* Get the "model" context */
	chan = Tcl_GetChannel(interp, model, &mode);
	if (chan == (Tcl_Channel) NULL) {
	    return TCL_ERROR;
	}
	if (channelTypeVersion == TLS_CHANNEL_VERSION_2) {
	    /*
	     * 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", NULL);
	    return TCL_ERROR;
	}
	statePtr = (State *) Tcl_GetChannelInstanceData(chan);
	ctx = statePtr->ctx;
    } else {
	if ((ctx = CTX_Init(interp, proto, key, cert, CAdir, CAfile, ciphers))
	    == (SSL_CTX*)0) {
	    return TCL_ERROR;
	}
    }

    /* new SSL state */
    statePtr		= (State *) Tcl_Alloc((unsigned) sizeof(State));
    statePtr->self	= (Tcl_Channel)NULL;
    statePtr->timer	= (Tcl_TimerToken)NULL;

    statePtr->flags	= flags;
    statePtr->watchMask	= 0;
    statePtr->mode	= 0;

    statePtr->interp	= interp;
    statePtr->callback	= (Tcl_Obj *)0;
    statePtr->password	= (Tcl_Obj *)0;

    statePtr->vflags	= verify;
    statePtr->ssl	= (SSL*)0;
    statePtr->ctx	= ctx;
    statePtr->ctx	= (SSL_CTX*)0;
    statePtr->bio	= (BIO*)0;
    statePtr->p_bio	= (BIO*)0;

    statePtr->err	= "";

    /* allocate script */
    if (script) {
	char *tmp = Tcl_GetStringFromObj(script, NULL);
	if (tmp && *tmp) {
	    statePtr->callback = Tcl_DuplicateObj(script);
	    Tcl_IncrRefCount(statePtr->callback);
	}
    }

    /* allocate password */
    if (password) {
	char *tmp = Tcl_GetStringFromObj(password, NULL);
	if (tmp && *tmp) {
	    statePtr->password = Tcl_DuplicateObj(password);
	    Tcl_IncrRefCount(statePtr->password);
	}
    }

    if (model != NULL) {
	int mode;
	/* Get the "model" context */
	chan = Tcl_GetChannel(interp, model, &mode);
	if (chan == (Tcl_Channel) NULL) {
	    Tls_Free((char *) statePtr);
	    return TCL_ERROR;
	}
	if (channelTypeVersion == TLS_CHANNEL_VERSION_2) {
	    /*
	     * 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", NULL);
	    Tls_Free((char *) statePtr);
	    return TCL_ERROR;
	}
	ctx = ((State *)Tcl_GetChannelInstanceData(chan))->ctx;
    } else {
	if ((ctx = CTX_Init(statePtr, proto, key, cert, CAdir, CAfile, ciphers))
	    == (SSL_CTX*)0) {
	    Tls_Free((char *) 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.
     */

	/*
	 * No use of Tcl_EventuallyFree because no possible Tcl_Preserve.
	 */
	Tls_Free((char *) statePtr);
        return TCL_ERROR;
    }

    /* allocate script */
    if (script) {
	char *tmp = Tcl_GetStringFromObj(script, NULL);
	if (tmp && *tmp) {
	    statePtr->callback = Tcl_DuplicateObj(script);
	    Tcl_IncrRefCount(statePtr->callback);
	}
    }
    /* This is only needed because of a bug in OpenSSL, where the
     * ssl->verify_callback is not referenced!!! (Must be done
     * *before* SSL_new() is called!
     */
    SSL_CTX_set_verify(statePtr->ctx, verify, VerifyCallback);

    /*
     * SSL Initialization
     */

    statePtr->ssl = SSL_new(statePtr->ctx);
    if (!statePtr->ssl) {
        /* SSL library error */
        Tcl_AppendResult(interp, "couldn't construct ssl session: ", REASON(),
		(char *) NULL);
	Tls_Free((char *) statePtr);
        return TCL_ERROR;
    }

    /*
     * SSL Callbacks
     */

    SSL_set_app_data(statePtr->ssl, (VOID *)statePtr);	/* point back to us */

    /*
     * The following is broken - we need is to set the
     * verify_mode, but the library ignores the verify_callback!!!
     */
    /*SSL_set_verify(statePtr->ssl, verify, VerifyCallback);*/
    SSL_set_verify(statePtr->ssl, verify, VerifyCallback);

    SSL_CTX_set_info_callback(statePtr->ctx, InfoCallback);

    /* Create Tcl_Channel BIO Handler */
    statePtr->p_bio	= BIO_new_tcl(statePtr, BIO_CLOSE);
    statePtr->bio	= BIO_new(BIO_f_ssl());

 * Side effects:
 *	constructs SSL context (CTX)
 *
 *-------------------------------------------------------------------
 */

static SSL_CTX *
CTX_Init(interp, proto, key, cert, CAdir, CAfile, ciphers)
    Tcl_Interp *interp;
CTX_Init(statePtr, proto, key, cert, CAdir, CAfile, ciphers)
    State *statePtr;
    int proto;
    char *key;
    char *cert;
    char *CAdir;
    char *CAfile;
    char *ciphers;
{
    Tcl_Interp *interp = statePtr->interp;
    SSL_CTX *ctx = NULL;
    Tcl_DString ds;
    Tcl_DString ds1;
    int off = 0;

    /* create SSL context */
#if !defined(NO_SSL2) && !defined(NO_SSL3)

    if (ciphers != NULL)
	SSL_CTX_set_cipher_list(ctx, ciphers);

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

#ifndef BSAFE
    SSL_CTX_set_default_passwd_cb_userdata(ctx, (void *)interp);
    SSL_CTX_set_default_passwd_cb_userdata(ctx, (void *)statePtr);
#endif

#ifndef NO_DH
    {
	DH* dh = get_dh512();
	SSL_CTX_set_tmp_dh(ctx, dh);
	DH_free(dh);

        /* get the private key associated with this certificate */
        if (key == NULL) key=cert;

        if (SSL_CTX_use_PrivateKey_file(ctx, F2N( key, &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 ", key, " ",
                             REASON(), (char *) NULL);
            SSL_CTX_free(ctx);
            return (SSL_CTX *)0;
        }
	Tcl_DStringFree(&ds);

	peer	= SSL_get_certificate(statePtr->ssl);
    if (peer) {
	objPtr = Tls_NewX509Obj(interp, peer);
    } else {
	objPtr = Tcl_NewListObj(0, NULL);
    }

    Tcl_ListObjAppendElement (interp, objPtr, Tcl_NewStringObj ("sbits", -1));
    Tcl_ListObjAppendElement (interp, objPtr,
	    Tcl_NewStringObj ("sbits", -1));
    Tcl_ListObjAppendElement (interp, objPtr,
	    Tcl_NewIntObj (SSL_get_cipher_bits (statePtr->ssl, NULL)));

    ciphers = (char*)SSL_get_cipher(statePtr->ssl);
    if (ciphers != NULL && strcmp(ciphers, "(NONE)")!=0) {
	Tcl_ListObjAppendElement(interp, objPtr,
		Tcl_NewStringObj("cipher", -1));
	Tcl_ListObjAppendElement(interp, objPtr,
		Tcl_NewStringObj(SSL_get_cipher(statePtr->ssl), -1));
    }
    Tcl_SetObjResult( interp, objPtr);
    return TCL_OK;
}

/*
 *-------------------------------------------------------------------
 *
 * VersionObjCmd -- return version string from OpenSSL.
 *
 * Results:
 *	A standard Tcl result.
 *
 * Side effects:
 *	None.
 *
 *-------------------------------------------------------------------
 */
static int
VersionObjCmd(clientData, interp, objc, objv)
    ClientData clientData;	/* Not used. */
    Tcl_Interp *interp;
    int objc;
    Tcl_Obj	*CONST objv[];
{
    Tcl_Obj *objPtr;

    objPtr = Tcl_NewStringObj(OPENSSL_VERSION_TEXT, -1);

    Tcl_SetObjResult(interp, objPtr);
    return TCL_OK;
}

/*
 *-------------------------------------------------------------------
 *
 * Tls_Free --
 *
 *	This procedure cleans up when a SSL socket based channel

	statePtr->timer = NULL;
    }

    if (statePtr->ssl) {
	SSL_shutdown(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;
    }
}

/*
 *-------------------------------------------------------------------
 *
 * Tls_Init --

	    (ClientData) 0, (Tcl_CmdDeleteProc *) NULL);

    Tcl_CreateObjCommand(interp, "tls::import", ImportObjCmd,
	    (ClientData) 0, (Tcl_CmdDeleteProc *) NULL);

    Tcl_CreateObjCommand(interp, "tls::status", StatusObjCmd,
	    (ClientData) 0, (Tcl_CmdDeleteProc *) NULL);

    Tcl_CreateObjCommand(interp, "tls::version", VersionObjCmd,
	    (ClientData) 0, (Tcl_CmdDeleteProc *) NULL);

    return Tcl_PkgProvide(interp, PACKAGE, VERSION);
}

/*
 *------------------------------------------------------*
 *