/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/*
 * CMS digestedData methods.
 */

#include "cmslocal.h"

#include "secitem.h"
#include "secasn1.h"
#include "secoid.h"
#include "secerr.h"

/*
 * NSS_CMSDigestedData_Create - create a digestedData object (presumably for encoding)
 *
 * version will be set by NSS_CMSDigestedData_Encode_BeforeStart
 * digestAlg is passed as parameter
 * contentInfo must be filled by the user
 * digest will be calculated while encoding
 */
NSSCMSDigestedData *
NSS_CMSDigestedData_Create(NSSCMSMessage *cmsg, SECAlgorithmID *digestalg)
{
    void *mark;
    NSSCMSDigestedData *digd;
    PLArenaPool *poolp;

    poolp = cmsg->poolp;

    mark = PORT_ArenaMark(poolp);

    digd = (NSSCMSDigestedData *)PORT_ArenaZAlloc(poolp, sizeof(NSSCMSDigestedData));
    if (digd == NULL)
        goto loser;

    digd->cmsg = cmsg;

    if (SECOID_CopyAlgorithmID(poolp, &(digd->digestAlg), digestalg) != SECSuccess)
        goto loser;

    PORT_ArenaUnmark(poolp, mark);
    return digd;

loser:
    PORT_ArenaRelease(poolp, mark);
    return NULL;
}

/*
 * NSS_CMSDigestedData_Destroy - destroy a digestedData object
 */
void
NSS_CMSDigestedData_Destroy(NSSCMSDigestedData *digd)
{
    /* everything's in a pool, so don't worry about the storage */
    NSS_CMSContentInfo_Destroy(&(digd->contentInfo));
    return;
}

/*
 * NSS_CMSDigestedData_GetContentInfo - return pointer to digestedData object's contentInfo
 */
NSSCMSContentInfo *
NSS_CMSDigestedData_GetContentInfo(NSSCMSDigestedData *digd)
{
    return &(digd->contentInfo);
}

/*
 * NSS_CMSDigestedData_Encode_BeforeStart - do all the necessary things to a DigestedData
 *     before encoding begins.
 *
 * In particular:
 *  - set the right version number. The contentInfo's content type must be set up already.
 */
SECStatus
NSS_CMSDigestedData_Encode_BeforeStart(NSSCMSDigestedData *digd)
{
    unsigned long version;
    SECItem *dummy;

    version = NSS_CMS_DIGESTED_DATA_VERSION_DATA;
    if (!NSS_CMSType_IsData(NSS_CMSContentInfo_GetContentTypeTag(
            &(digd->contentInfo))))
        version = NSS_CMS_DIGESTED_DATA_VERSION_ENCAP;

    dummy = SEC_ASN1EncodeInteger(digd->cmsg->poolp, &(digd->version), version);
    return (dummy == NULL) ? SECFailure : SECSuccess;
}

/*
 * NSS_CMSDigestedData_Encode_BeforeData - do all the necessary things to a DigestedData
 *     before the encapsulated data is passed through the encoder.
 *
 * In detail:
 *  - set up the digests if necessary
 */
SECStatus
NSS_CMSDigestedData_Encode_BeforeData(NSSCMSDigestedData *digd)
{
    SECStatus rv = NSS_CMSContentInfo_Private_Init(&digd->contentInfo);
    if (rv != SECSuccess) {
        return SECFailure;
    }

    /* set up the digests */
    if (digd->digestAlg.algorithm.len != 0 && digd->digest.len == 0) {
        /* if digest is already there, do nothing */
        digd->contentInfo.privateInfo->digcx = NSS_CMSDigestContext_StartSingle(&(digd->digestAlg));
        if (digd->contentInfo.privateInfo->digcx == NULL)
            return SECFailure;
    }
    return SECSuccess;
}

/*
 * NSS_CMSDigestedData_Encode_AfterData - do all the necessary things to a DigestedData
 *     after all the encapsulated data was passed through the encoder.
 *
 * In detail:
 *  - finish the digests
 */
SECStatus
NSS_CMSDigestedData_Encode_AfterData(NSSCMSDigestedData *digd)
{
    SECStatus rv = SECSuccess;
    /* did we have digest calculation going on? */
    if (digd->contentInfo.privateInfo && digd->contentInfo.privateInfo->digcx) {
        rv = NSS_CMSDigestContext_FinishSingle(digd->contentInfo.privateInfo->digcx,
                                               digd->cmsg->poolp,
                                               &(digd->digest));
        /* error has been set by NSS_CMSDigestContext_FinishSingle */
        digd->contentInfo.privateInfo->digcx = NULL;
    }

    return rv;
}

/*
 * NSS_CMSDigestedData_Decode_BeforeData - do all the necessary things to a DigestedData
 *     before the encapsulated data is passed through the encoder.
 *
 * In detail:
 *  - set up the digests if necessary
 */
SECStatus
NSS_CMSDigestedData_Decode_BeforeData(NSSCMSDigestedData *digd)
{
    SECStatus rv;

    /* is there a digest algorithm yet? */
    if (digd->digestAlg.algorithm.len == 0)
        return SECFailure;

    rv = NSS_CMSContentInfo_Private_Init(&digd->contentInfo);
    if (rv != SECSuccess) {
        return SECFailure;
    }

    digd->contentInfo.privateInfo->digcx = NSS_CMSDigestContext_StartSingle(&(digd->digestAlg));
    if (digd->contentInfo.privateInfo->digcx == NULL)
        return SECFailure;

    return SECSuccess;
}

/*
 * NSS_CMSDigestedData_Decode_AfterData - do all the necessary things to a DigestedData
 *     after all the encapsulated data was passed through the encoder.
 *
 * In detail:
 *  - finish the digests
 */
SECStatus
NSS_CMSDigestedData_Decode_AfterData(NSSCMSDigestedData *digd)
{
    SECStatus rv = SECSuccess;
    /* did we have digest calculation going on? */
    if (digd->contentInfo.privateInfo && digd->contentInfo.privateInfo->digcx) {
        rv = NSS_CMSDigestContext_FinishSingle(digd->contentInfo.privateInfo->digcx,
                                               digd->cmsg->poolp,
                                               &(digd->cdigest));
        /* error has been set by NSS_CMSDigestContext_FinishSingle */
        digd->contentInfo.privateInfo->digcx = NULL;
    }

    return rv;
}

/*
 * NSS_CMSDigestedData_Decode_AfterEnd - finalize a digestedData.
 *
 * In detail:
 *  - check the digests for equality
 */
SECStatus
NSS_CMSDigestedData_Decode_AfterEnd(NSSCMSDigestedData *digd)
{
    /* did we have digest calculation going on? */
    if (digd->cdigest.len != 0) {
        /* XXX comparision btw digest & cdigest */
        /* XXX set status */
        /* TODO!!!! */
    }

    return SECSuccess;
}
