src/generic/crypt.c

/*
 * cryp.c --- The encryption facility of websh
 * nca-073-9
 * 
 * Copyright (c) 1996-2000 by Netcetera AG.
 * Copyright (c) 2001 by Apache Software Foundation.
 * All rights reserved.
 *
 * See the file "license.terms" for information on usage and
 * redistribution of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * @(#) $Id$
 *
 */

#include <tcl.h>
#include "crypt.h"
#include "log.h"
#include "macros.h"
#include "nca_d.h"

/* ----------------------------------------------------------------------------
 * init
 * ------------------------------------------------------------------------- */
int crypt_Init(Tcl_Interp * interp)
{

    CryptData *cryptData;
    Tcl_Obj *tmp;

    /* --------------------------------------------------------------------------
     * interpreter running ?
     * ----------------------------------------------------------------------- */
    if (interp == NULL)
	return TCL_ERROR;

    /* --------------------------------------------------------------------------
     * init internal data, and register with interp
     * ----------------------------------------------------------------------- */
    cryptData = createCryptData();
    WebAssertData(interp, cryptData, "web::crypt", TCL_ERROR);

    /* --------------------------------------------------------------------------
     * register data with interp
     * ----------------------------------------------------------------------- */
    Tcl_SetAssocData(interp, WEB_CRYPT_ASSOC_DATA,
		     destroyCryptData, (ClientData) cryptData);

    /* --------------------------------------------------------------------------
     * register commands
     * ----------------------------------------------------------------------- */
    Tcl_CreateObjCommand(interp, "web::encrypt", Web_Encrypt, NULL, NULL);

    Tcl_CreateObjCommand(interp, "web::decrypt", Web_Decrypt, NULL, NULL);

    /* --------------------------------------------------------------------------
     * default encrypt and decrypt chains
     * ----------------------------------------------------------------------- */
    tmp = Tcl_NewStringObj(WEB_ENCRYPTDEFAULT, -1);
    cryptData->encryptChain = Tcl_NewListObj(1, &tmp);
    Tcl_IncrRefCount(cryptData->encryptChain);

    tmp = Tcl_NewStringObj(WEB_DECRYPTDEFAULT, -1);
    cryptData->decryptChain = Tcl_NewListObj(1, &tmp);
    Tcl_IncrRefCount(cryptData->decryptChain);

    /* --------------------------------------------------------------------------
     * done
     * ----------------------------------------------------------------------- */
    return TCL_OK;
}

/* ----------------------------------------------------------------------------
 * createCryptData --
 * ------------------------------------------------------------------------- */
CryptData *createCryptData()
{

    CryptData *cryptData = NULL;

    cryptData = WebAllocInternalData(CryptData);

    if (cryptData != NULL) {

	cryptData->encryptChain = NULL;
	cryptData->decryptChain = NULL;
    }

    return cryptData;
}

/* ----------------------------------------------------------------------------
 * destroyCryptData --
 * ------------------------------------------------------------------------- */
void destroyCryptData(ClientData clientData, Tcl_Interp * interp)
{

    CryptData *cryptData = NULL;

    if (clientData != NULL) {

	cryptData = (CryptData *) clientData;

	WebDecrRefCountIfNotNull(cryptData->encryptChain);
	WebDecrRefCountIfNotNull(cryptData->decryptChain);

	WebFreeIfNotNull(cryptData);
    }
}


/* --------------------------------------------------------------------------
 * Web_Encrypt -- in: list, out: str
 * ------------------------------------------------------------------------*/
int Web_Encrypt(ClientData clientData,
		Tcl_Interp * interp, int objc, Tcl_Obj * CONST objv[])
{

    WebAssertObjc(objc != 2, 1, "string");

    return doencrypt(interp, objv[1], 0);
}



/* --------------------------------------------------------------------------
 * Web_Decrypt
 * ------------------------------------------------------------------------*/
int Web_Decrypt(ClientData clientData,
		Tcl_Interp * interp, int objc, Tcl_Obj * CONST objv[])
{

    /* ------------------------------------------------------------------------
     * arg check: web::decrypt msg
     *            0            1
     * --------------------------------------------------------------------- */
    WebAssertObjc(objc != 2, 1, "string");

    return dodecrypt(interp, objv[1], 0);
}


/* --------------------------------------------------------------------------
 * C API -- sets interp result
 * ------------------------------------------------------------------------*/
int doencrypt(Tcl_Interp * interp, Tcl_Obj * in, int internal)
{

    CryptData *cryptData = NULL;
    int lobjc = -1;
    Tcl_Obj **lobjv = NULL;
    int i = -1;

    if ((interp == NULL) || (in == NULL))
	return TCL_ERROR;

    cryptData =
	(CryptData *) Tcl_GetAssocData(interp, WEB_CRYPT_ASSOC_DATA, NULL);
    WebAssertData(interp, cryptData, "doencrypt", TCL_ERROR);

    WebAssertData(interp, cryptData->encryptChain, "doencrypt", TCL_ERROR);

    /* ------------------------------------------------------------------------
     * get elements from encryptchain
     * --------------------------------------------------------------------- */
    if (Tcl_ListObjGetElements(interp, cryptData->encryptChain,
			       &lobjc, &lobjv) == TCL_ERROR) {

	LOG_MSG(interp, WRITE_LOG | SET_RESULT,
		__FILE__, __LINE__,
		"web::encrypt", WEBLOG_ERROR,
		"error accessing encryptchain", NULL);
	return TCL_ERROR;
    }

    /* --------------------------------------------------------------------------
     * ... and loop
     * ----------------------------------------------------------------------- */
    for (i = 0; i <= lobjc; i++) {

	int res = 0;
	Tcl_Obj *cmd = NULL;

	if (i < lobjc) {
	  if (lobjv[i] != NULL) {
	    cmd = Tcl_DuplicateObj(lobjv[i]);
	    Tcl_IncrRefCount(cmd);
	  } else {
	    cmd = NULL;
	  }
	}
	else {
	    if (!internal) {
		Tcl_SetObjResult(interp, in);
		return TCL_OK;
	    }
	    cmd = Tcl_NewListObj(0, NULL);
	    Tcl_IncrRefCount(cmd);
	    Tcl_ListObjAppendElement(interp, cmd,
				     Tcl_NewStringObj("web::list2uri", -1));
	}

	if (cmd != NULL) {

	    if (Tcl_ListObjAppendElement(interp, cmd, in) != TCL_OK) {
		Tcl_DecrRefCount(cmd);
		return TCL_ERROR;
	    }

	    res = Tcl_EvalObjEx(interp, cmd, TCL_EVAL_DIRECT);
	    Tcl_DecrRefCount(cmd);

	    switch (res) {
	    case TCL_OK:
		return TCL_OK;
		break;
	    case TCL_CONTINUE:
		break;
	    default:
		if (i < lobjc) {
		    LOG_MSG(interp, WRITE_LOG | SET_RESULT,
			    __FILE__, __LINE__,
			    "web::encrypt", WEBLOG_ERROR,
			    "encrypt method \"", Tcl_GetString(lobjv[i]),
			    "\": ", Tcl_GetStringResult(interp), NULL);
		}
		return TCL_ERROR;
		break;
	    }
	}
    }

    LOG_MSG(interp, WRITE_LOG | SET_RESULT,
	    __FILE__, __LINE__,
	    "web::encrypt", WEBLOG_ERROR,
	    "no matching encryption method found", NULL);

    return TCL_ERROR;
}

/* --------------------------------------------------------------------------
 * C API
 * ------------------------------------------------------------------------*/
int dodecrypt(Tcl_Interp * interp, Tcl_Obj * in, int internal)
{

    CryptData *cryptData = NULL;
    int lobjc = -1;
    Tcl_Obj **lobjv = NULL;
    int i = -1;

    if ((interp == NULL) || (in == NULL))
	return TCL_ERROR;

    cryptData =
	(CryptData *) Tcl_GetAssocData(interp, WEB_CRYPT_ASSOC_DATA, NULL);
    WebAssertData(interp, cryptData, "web::decrypt", TCL_ERROR);

    WebAssertData(interp, cryptData->decryptChain, "web::decrypt", TCL_ERROR);

    /* ------------------------------------------------------------------------
     * loop over encryptchain
     * --------------------------------------------------------------------- */
    if (Tcl_ListObjGetElements(interp, cryptData->decryptChain,
			       &lobjc, &lobjv) == TCL_ERROR) {
	LOG_MSG(interp, WRITE_LOG | SET_RESULT,
		__FILE__, __LINE__,
		"web::decrypt", WEBLOG_ERROR,
		"error accessing decryptchain", NULL);
	return TCL_ERROR;
    }

    /* --------------------------------------------------------------------------
     * now see what we got
     * ----------------------------------------------------------------------- */
    for (i = 0; i <= lobjc; i++) {

	int res = 0;
	Tcl_Obj *cmd = NULL;

	if (i < lobjc) {
	  if (lobjv[i] != NULL) {
	    cmd = Tcl_DuplicateObj(lobjv[i]);
	    Tcl_IncrRefCount(cmd);
	  } else {
	    cmd = NULL;
	  }
	}
	else {
	    if (!internal) {
		Tcl_SetObjResult(interp, in);
		return TCL_OK;
	    }
	    cmd = Tcl_NewListObj(0, NULL);
	    Tcl_IncrRefCount(cmd);
	    Tcl_ListObjAppendElement(interp, cmd,
				     Tcl_NewStringObj("web::uri2list", -1));
	}

	if (cmd != NULL) {

	    if (Tcl_ListObjAppendElement(interp, cmd, in) != TCL_OK) {
		Tcl_DecrRefCount(cmd);
		return TCL_ERROR;
	    }

	    res = Tcl_EvalObjEx(interp, cmd, TCL_EVAL_DIRECT);
	    Tcl_DecrRefCount(cmd);

	    switch (res) {
	    case TCL_OK:
		return TCL_OK;
		break;
	    case TCL_CONTINUE:
		break;
	    default:
		if (i < lobjc) {
		    LOG_MSG(interp, WRITE_LOG | SET_RESULT,
			    __FILE__, __LINE__,
			    "web::decrypt", WEBLOG_ERROR,
			    "decrypt method \"", Tcl_GetString(lobjv[i]),
			    "\": ", Tcl_GetStringResult(interp), NULL);
		}
		return TCL_ERROR;
		break;
	    }
	}
    }

    LOG_MSG(interp, WRITE_LOG | SET_RESULT,
	    __FILE__, __LINE__,
	    "web::decrypt", WEBLOG_ERROR,
	    "no matching decryption method found", NULL);


    return TCL_ERROR;
}