/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include <pthread.h>
#include <security/cryptoki.h>
#include "softGlobal.h"
#include "softSession.h"
#include "softObject.h"
#include "softOps.h"


CK_RV
C_DecryptInit(CK_SESSION_HANDLE hSession, CK_MECHANISM_PTR pMechanism,
    CK_OBJECT_HANDLE hKey)
{

        CK_RV           rv;
        soft_session_t  *session_p;
        soft_object_t   *key_p;
        boolean_t       lock_held = B_FALSE;

        if (!softtoken_initialized)
                return (CKR_CRYPTOKI_NOT_INITIALIZED);

        /* Obtain the session pointer. */
        rv = handle2session(hSession, &session_p);
        if (rv != CKR_OK)
                return (rv);

        if (pMechanism == NULL) {
                rv = CKR_ARGUMENTS_BAD;
                goto clean_exit;
        }

        /* Obtain the object pointer. */
        HANDLE2OBJECT(hKey, key_p, rv);
        if (rv != CKR_OK)
                goto clean_exit;

        /* Check to see if key object allows for decryption. */
        if (!(key_p->bool_attr_mask & DECRYPT_BOOL_ON)) {
                rv = CKR_KEY_FUNCTION_NOT_PERMITTED;
                goto clean_exit1;
        }

        (void) pthread_mutex_lock(&session_p->session_mutex);
        lock_held = B_TRUE;

        /* Check to see if decrypt operation is already active. */
        if (session_p->decrypt.flags & CRYPTO_OPERATION_ACTIVE) {
                /* free the memory to avoid memory leak */
                soft_crypt_cleanup(session_p, B_FALSE, lock_held);
        }

        /*
         * This active flag will remain ON until application calls either
         * C_Decrypt or C_DecryptFinal to actually obtain the final piece
         * of plaintext.
         */
        session_p->decrypt.flags = CRYPTO_OPERATION_ACTIVE;

        (void) pthread_mutex_unlock(&session_p->session_mutex);
        lock_held = B_FALSE;

        rv = soft_decrypt_init(session_p, pMechanism, key_p);

        if (rv != CKR_OK) {
                (void) pthread_mutex_lock(&session_p->session_mutex);
                session_p->decrypt.flags &= ~CRYPTO_OPERATION_ACTIVE;
                lock_held = B_TRUE;
        }

clean_exit1:
        OBJ_REFRELE(key_p);
clean_exit:
        SES_REFRELE(session_p, lock_held);
        return (rv);
}


CK_RV
C_Decrypt(CK_SESSION_HANDLE hSession, CK_BYTE_PTR pEncryptedData,
    CK_ULONG ulEncryptedDataLen, CK_BYTE_PTR pData, CK_ULONG_PTR pulDataLen)
{

        CK_RV           rv;
        soft_session_t  *session_p;
        boolean_t       lock_held = B_FALSE;

        if (!softtoken_initialized)
                return (CKR_CRYPTOKI_NOT_INITIALIZED);

        /* Obatin the session pointer. */
        rv = handle2session(hSession, &session_p);
        if (rv != CKR_OK)
                return (rv);

        /*
         * Only check if input buffer is null.  How to handle zero input
         * length depents on the mechanism in use.  For secret key mechanisms,
         * unpadded ones yield zero length output, but padded ones always
         * result in smaller than original, possibly zero, length output.
         */
        if (pEncryptedData == NULL) {
                rv = CKR_ARGUMENTS_BAD;
                goto clean_exit;
        }

        /*
         * No need to check pData because application might
         * just want to know the length of decrypted data.
         */
        if (pulDataLen == NULL) {
                rv = CKR_ARGUMENTS_BAD;
                goto clean_exit;
        }

        (void) pthread_mutex_lock(&session_p->session_mutex);
        lock_held = B_TRUE;

        /* Application must call C_DecryptInit before calling C_Decrypt. */
        if (!(session_p->decrypt.flags & CRYPTO_OPERATION_ACTIVE)) {
                SES_REFRELE(session_p, lock_held);
                return (CKR_OPERATION_NOT_INITIALIZED);
        }

        /*
         * C_Decrypt must be called without intervening C_DecryptUpdate
         * calls.
         */
        if (session_p->decrypt.flags & CRYPTO_OPERATION_UPDATE) {
                /*
                 * C_Decrypt can not be used to terminate a multi-part
                 * operation, so we'll leave the active decrypt operation
                 * flag on and let the application continue with the
                 * decrypt update operation.
                 */
                SES_REFRELE(session_p, lock_held);
                return (CKR_FUNCTION_FAILED);
        }

        (void) pthread_mutex_unlock(&session_p->session_mutex);
        lock_held = B_FALSE;

        rv = soft_decrypt(session_p, pEncryptedData, ulEncryptedDataLen,
            pData, pulDataLen);

        if ((rv == CKR_BUFFER_TOO_SMALL) ||
            (pData == NULL && rv == CKR_OK)) {
                /*
                 * We will not terminate the active decrypt operation flag,
                 * when the application-supplied buffer is too small, or
                 * the application asks for the length of buffer to hold
                 * the plaintext.
                 */
                SES_REFRELE(session_p, lock_held);
                return (rv);
        }

clean_exit:
        /* Clear context, free key, and release session counter */
        soft_crypt_cleanup(session_p, B_FALSE, B_FALSE);

        return (rv);
}


CK_RV
C_DecryptUpdate(CK_SESSION_HANDLE hSession, CK_BYTE_PTR pEncryptedPart,
    CK_ULONG ulEncryptedPartLen, CK_BYTE_PTR pPart,
    CK_ULONG_PTR pulPartLen)
{

        CK_RV           rv;
        soft_session_t  *session_p;
        boolean_t       lock_held = B_FALSE;

        if (!softtoken_initialized)
                return (CKR_CRYPTOKI_NOT_INITIALIZED);

        /* Obtain the session pointer. */
        rv = handle2session(hSession, &session_p);
        if (rv != CKR_OK)
                return (rv);

        /*
         * Only check if input buffer is null.  How to handle zero input
         * length depents on the mechanism in use.  For secret key mechanisms,
         * unpadded ones yeild zero length output, but padded ones always
         * result in smaller than original, possibly zero, length output.
         */
        if (pEncryptedPart == NULL) {
                rv = CKR_ARGUMENTS_BAD;
                goto clean_exit;
        }

        /*
         * Only check if pulPartLen is NULL.
         * No need to check if pPart is NULL because application
         * might just ask for the length of buffer to hold the
         * recovered data.
         */
        if (pulPartLen == NULL) {
                rv = CKR_ARGUMENTS_BAD;
                goto clean_exit;
        }

        (void) pthread_mutex_lock(&session_p->session_mutex);
        lock_held = B_TRUE;

        /*
         * Application must call C_DecryptInit before calling
         * C_DecryptUpdate.
         */
        if (!(session_p->decrypt.flags & CRYPTO_OPERATION_ACTIVE)) {
                SES_REFRELE(session_p, lock_held);
                return (CKR_OPERATION_NOT_INITIALIZED);
        }

        session_p->decrypt.flags |= CRYPTO_OPERATION_UPDATE;

        (void) pthread_mutex_unlock(&session_p->session_mutex);
        lock_held = B_FALSE;

        rv = soft_decrypt_update(session_p, pEncryptedPart,
            ulEncryptedPartLen, pPart, pulPartLen);

        /*
         * If CKR_OK or CKR_BUFFER_TOO_SMALL, don't terminate the
         * current decryption operation.
         */
        if ((rv == CKR_OK) || (rv == CKR_BUFFER_TOO_SMALL)) {
                SES_REFRELE(session_p, lock_held);
                return (rv);
        }

clean_exit:
        /*
         * After an error occurred, terminate the current decrypt
         * operation by resetting the active and update flags.
         */
        soft_crypt_cleanup(session_p, B_FALSE, lock_held);

        return (rv);
}

CK_RV
C_DecryptFinal(CK_SESSION_HANDLE hSession, CK_BYTE_PTR pLastPart,
    CK_ULONG_PTR pulLastPartLen)
{

        CK_RV           rv;
        soft_session_t  *session_p;
        boolean_t       lock_held = B_FALSE;

        if (!softtoken_initialized)
                return (CKR_CRYPTOKI_NOT_INITIALIZED);

        /* Obtain the session pointer. */
        rv = handle2session(hSession, &session_p);
        if (rv != CKR_OK)
                return (rv);

        if (pulLastPartLen == NULL) {
                rv = CKR_ARGUMENTS_BAD;
                goto clean_exit;
        }

        (void) pthread_mutex_lock(&session_p->session_mutex);
        lock_held = B_TRUE;

        /*
         * Application must call C_DecryptInit before calling
         * C_DecryptFinal.
         */
        if (!(session_p->decrypt.flags & CRYPTO_OPERATION_ACTIVE)) {
                SES_REFRELE(session_p, lock_held);
                return (CKR_OPERATION_NOT_INITIALIZED);
        }

        (void) pthread_mutex_unlock(&session_p->session_mutex);
        lock_held = B_FALSE;

        rv = soft_decrypt_final(session_p, pLastPart, pulLastPartLen);

        if ((rv == CKR_BUFFER_TOO_SMALL) ||
            (pLastPart == NULL && rv == CKR_OK)) {
                /*
                 * We will not terminate the active decrypt operation flag,
                 * when the application-supplied buffer is too small, or
                 * the application asks for the length of buffer to hold
                 * the plaintext.
                 */
                SES_REFRELE(session_p, lock_held);
                return (rv);
        }

        /* Terminates the active encrypt operation. */
        (void) pthread_mutex_lock(&session_p->session_mutex);
        session_p->decrypt.flags = 0;
        lock_held = B_TRUE;
        SES_REFRELE(session_p, lock_held);
        return (rv);

clean_exit:
        /* Terminates the active decrypt operation */
        soft_crypt_cleanup(session_p, B_FALSE, lock_held);

        return (rv);
}