/* 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/. */

/*

 * PKCS7 implementation -- the exported parts that are used whether

 * creating or decoding.

 */

#include "p7local.h"

#include "cert.h"

#include "secitem.h"

#include "secoid.h"

#include "pk11func.h"

/*

 * Find out (saving pointer to lookup result for future reference)

 * and return the inner content type.

 */

SECOidTag

SEC_PKCS7ContentType(SEC_PKCS7ContentInfo *cinfo)

{

    if (cinfo->contentTypeTag == NULL)

        cinfo->contentTypeTag = SECOID_FindOID(&(cinfo->contentType));

    if (cinfo->contentTypeTag == NULL)

        return SEC_OID_UNKNOWN;

    return cinfo->contentTypeTag->offset;

}

/*

 * Destroy a PKCS7 contentInfo and all of its sub-pieces.

 */

void

SEC_PKCS7DestroyContentInfo(SEC_PKCS7ContentInfo *cinfo)

{

    SECOidTag kind;

    CERTCertificate **certs;

    CERTCertificateList **certlists;

    SEC_PKCS7SignerInfo **signerinfos;

    SEC_PKCS7RecipientInfo **recipientinfos;

    PORT_Assert(cinfo->refCount > 0);

    if (cinfo->refCount <= 0)

        return;

    cinfo->refCount--;

    if (cinfo->refCount > 0)

        return;

    certs = NULL;

    certlists = NULL;

    recipientinfos = NULL;

    signerinfos = NULL;

    kind = SEC_PKCS7ContentType(cinfo);

    switch (kind) {

        case SEC_OID_PKCS7_ENVELOPED_DATA: {

            SEC_PKCS7EnvelopedData *edp;

            edp = cinfo->content.envelopedData;

            if (edp != NULL) {

                recipientinfos = edp->recipientInfos;

            }

        } break;

        case SEC_OID_PKCS7_SIGNED_DATA: {

            SEC_PKCS7SignedData *sdp;

            sdp = cinfo->content.signedData;

            if (sdp != NULL) {

                certs = sdp->certs;

                certlists = sdp->certLists;

                signerinfos = sdp->signerInfos;

            }

        } break;

        case SEC_OID_PKCS7_SIGNED_ENVELOPED_DATA: {

            SEC_PKCS7SignedAndEnvelopedData *saedp;

            saedp = cinfo->content.signedAndEnvelopedData;

            if (saedp != NULL) {

                certs = saedp->certs;

                certlists = saedp->certLists;

                recipientinfos = saedp->recipientInfos;

                signerinfos = saedp->signerInfos;

                if (saedp->sigKey != NULL)

                    PK11_FreeSymKey(saedp->sigKey);

            }

        } break;

        default:

            /* XXX Anything else that needs to be "manually" freed/destroyed? */

            break;

    }

    if (certs != NULL) {

        CERTCertificate *cert;

        while ((cert = *certs++) != NULL) {

            CERT_DestroyCertificate(cert);

        }

    }

    if (certlists != NULL) {

        CERTCertificateList *certlist;

        while ((certlist = *certlists++) != NULL) {

            CERT_DestroyCertificateList(certlist);

        }

    }

    if (recipientinfos != NULL) {

        SEC_PKCS7RecipientInfo *ri;

        while ((ri = *recipientinfos++) != NULL) {

            if (ri->cert != NULL)

                CERT_DestroyCertificate(ri->cert);

        }

    }

    if (signerinfos != NULL) {

        SEC_PKCS7SignerInfo *si;

        while ((si = *signerinfos++) != NULL) {

            if (si->cert != NULL)

                CERT_DestroyCertificate(si->cert);

            if (si->certList != NULL)

                CERT_DestroyCertificateList(si->certList);

        }

    }

    if (cinfo->poolp != NULL) {

        PORT_FreeArena(cinfo->poolp, PR_FALSE); /* XXX clear it? */

    }

}

/*

 * Return a copy of the given contentInfo.  The copy may be virtual

 * or may be real -- either way, the result needs to be passed to

 * SEC_PKCS7DestroyContentInfo later (as does the original).

 */

SEC_PKCS7ContentInfo *

SEC_PKCS7CopyContentInfo(SEC_PKCS7ContentInfo *cinfo)

{

    if (cinfo == NULL)

        return NULL;

    PORT_Assert(cinfo->refCount > 0);

    if (cinfo->created) {

        /*

         * Want to do a real copy of these; otherwise subsequent

         * changes made to either copy are likely to be a surprise.

         * XXX I suspect that this will not actually be called for yet,

         * which is why the assert, so to notice if it is...

         */

        PORT_Assert(0);

        /*

         * XXX Create a new pool here, and copy everything from

         * within.  For cert stuff, need to call the appropriate

         * copy functions, etc.

         */

    }

    cinfo->refCount++;

    return cinfo;

}

/*

 * Return a pointer to the actual content.  In the case of those types

 * which are encrypted, this returns the *plain* content.

 * XXX Needs revisiting if/when we handle nested encrypted types.

 */

SECItem *

SEC_PKCS7GetContent(SEC_PKCS7ContentInfo *cinfo)

{

    SECOidTag kind;

    kind = SEC_PKCS7ContentType(cinfo);

    switch (kind) {

        case SEC_OID_PKCS7_DATA:

            return cinfo->content.data;

        case SEC_OID_PKCS7_DIGESTED_DATA: {

            SEC_PKCS7DigestedData *digd;

            digd = cinfo->content.digestedData;

            if (digd == NULL)

                break;

            return SEC_PKCS7GetContent(&(digd->contentInfo));

        }

        case SEC_OID_PKCS7_ENCRYPTED_DATA: {

            SEC_PKCS7EncryptedData *encd;

            encd = cinfo->content.encryptedData;

            if (encd == NULL)

                break;

            return &(encd->encContentInfo.plainContent);

        }

        case SEC_OID_PKCS7_ENVELOPED_DATA: {

            SEC_PKCS7EnvelopedData *envd;

            envd = cinfo->content.envelopedData;

            if (envd == NULL)

                break;

            return &(envd->encContentInfo.plainContent);

        }

        case SEC_OID_PKCS7_SIGNED_DATA: {

            SEC_PKCS7SignedData *sigd;

            sigd = cinfo->content.signedData;

            if (sigd == NULL)

                break;

            return SEC_PKCS7GetContent(&(sigd->contentInfo));

        }

        case SEC_OID_PKCS7_SIGNED_ENVELOPED_DATA: {

            SEC_PKCS7SignedAndEnvelopedData *saed;

            saed = cinfo->content.signedAndEnvelopedData;

            if (saed == NULL)

                break;

            return &(saed->encContentInfo.plainContent);

        }

        default:

            PORT_Assert(0);

            break;

    }

    return NULL;

}

/*

 * XXX Fix the placement and formatting of the

 * following routines (i.e. make them consistent with the rest of

 * the pkcs7 code -- I think some/many belong in other files and

 * they all need a formatting/style rehaul)

 */

/* retrieve the algorithm identifier for encrypted data.

 * the identifier returned is a copy of the algorithm identifier

 * in the content info and needs to be freed after being used.

 *

 *   cinfo is the content info for which to retrieve the

 *     encryption algorithm.

 *

 * if the content info is not encrypted data or an error

 * occurs NULL is returned.

 */

SECAlgorithmID *

SEC_PKCS7GetEncryptionAlgorithm(SEC_PKCS7ContentInfo *cinfo)

{

    SECAlgorithmID *alg = 0;

    switch (SEC_PKCS7ContentType(cinfo)) {

        case SEC_OID_PKCS7_ENCRYPTED_DATA:

            alg = &cinfo->content.encryptedData->encContentInfo.contentEncAlg;

            break;

        case SEC_OID_PKCS7_ENVELOPED_DATA:

            alg = &cinfo->content.envelopedData->encContentInfo.contentEncAlg;

            break;

        case SEC_OID_PKCS7_SIGNED_ENVELOPED_DATA:

            alg = &cinfo->content.signedAndEnvelopedData

                       ->encContentInfo.contentEncAlg;

            break;

        default:

            alg = 0;

            break;

    }

    return alg;

}

/* set the content of the content info.  For data content infos,

 * the data is set.  For encrytped content infos, the plainContent

 * is set, and is expected to be encrypted later.

 *

 * cinfo is the content info where the data will be set

 *

 * buf is a buffer of the data to set

 *

 * len is the length of the data being set.

 *

 * in the event of an error, SECFailure is returned.  SECSuccess

 * indicates the content was successfully set.

 */

SECStatus

SEC_PKCS7SetContent(SEC_PKCS7ContentInfo *cinfo,

                    const char *buf,

                    unsigned long len)

{

    SECOidTag cinfo_type;

    SECStatus rv;

    SECItem content;

    SECOidData *contentTypeTag = NULL;

    content.type = siBuffer;

    content.data = (unsigned char *)buf;

    content.len = len;

    cinfo_type = SEC_PKCS7ContentType(cinfo);

    /* set inner content */

    switch (cinfo_type) {

        case SEC_OID_PKCS7_SIGNED_DATA:

            if (content.len > 0) {

                /* we "leak" the old content here, but as it's all in the pool */

                /* it does not really matter */

                /* create content item if necessary */

                if (cinfo->content.signedData->contentInfo.content.data == NULL)

                    cinfo->content.signedData->contentInfo.content.data = SECITEM_AllocItem(cinfo->poolp, NULL, 0);

                rv = SECITEM_CopyItem(cinfo->poolp,

                                      cinfo->content.signedData->contentInfo.content.data,

                                      &content);

            } else {

                cinfo->content.signedData->contentInfo.content.data->data = NULL;

                cinfo->content.signedData->contentInfo.content.data->len = 0;

                rv = SECSuccess;

            }

            if (rv == SECFailure)

                goto loser;

            break;

        case SEC_OID_PKCS7_ENCRYPTED_DATA:

            /* XXX this forces the inner content type to be "data" */

            /* do we really want to override without asking or reason? */

            contentTypeTag = SECOID_FindOIDByTag(SEC_OID_PKCS7_DATA);

            if (contentTypeTag == NULL)

                goto loser;

            rv = SECITEM_CopyItem(cinfo->poolp,

                                  &(cinfo->content.encryptedData->encContentInfo.contentType),

                                  &(contentTypeTag->oid));

            if (rv == SECFailure)

                goto loser;

            if (content.len > 0) {

                rv = SECITEM_CopyItem(cinfo->poolp,

                                      &(cinfo->content.encryptedData->encContentInfo.plainContent),

                                      &content);

            } else {

                cinfo->content.encryptedData->encContentInfo.plainContent.data = NULL;

                cinfo->content.encryptedData->encContentInfo.encContent.data = NULL;

                cinfo->content.encryptedData->encContentInfo.plainContent.len = 0;

                cinfo->content.encryptedData->encContentInfo.encContent.len = 0;

                rv = SECSuccess;

            }

            if (rv == SECFailure)

                goto loser;

            break;

        case SEC_OID_PKCS7_DATA:

            cinfo->content.data = (SECItem *)PORT_ArenaZAlloc(cinfo->poolp,

                                                              sizeof(SECItem));

            if (cinfo->content.data == NULL)

                goto loser;

            if (content.len > 0) {

                rv = SECITEM_CopyItem(cinfo->poolp,

                                      cinfo->content.data, &content);

            } else {

                /* handle case with NULL content */

                rv = SECSuccess;

            }

            if (rv == SECFailure)

                goto loser;

            break;

        default:

            goto loser;

    }

    return SECSuccess;

loser:

    return SECFailure;

}

/* the content of an encrypted data content info is decrypted.

 * it is assumed that for encrypted data, that the data has already

 * been set and is in the "encContent" field of the content info.

 *

 * cinfo is the content info to decrypt

 *

 * key is the key with which to perform the decryption.  if the

 *     algorithm is a password based encryption algorithm, the

 *     key is actually a password which will be processed per

 *     PKCS #5.

 *

 * in the event of an error, SECFailure is returned.  SECSuccess

 * indicates a success.

 */

SECStatus

SEC_PKCS7DecryptContents(PLArenaPool *poolp,

                         SEC_PKCS7ContentInfo *cinfo,

                         SECItem *key,

                         void *wincx)

{

    SECAlgorithmID *algid = NULL;

    SECStatus rv = SECFailure;

    SECItem *dest, *src;

    void *mark;

    PK11SymKey *eKey = NULL;

    PK11SlotInfo *slot = NULL;

    CK_MECHANISM_TYPE cryptoMechType;

    void *cx;

    SECItem *c_param = NULL;

    int bs;

    if ((cinfo == NULL) || (key == NULL))

        return SECFailure;

    if (SEC_PKCS7ContentType(cinfo) != SEC_OID_PKCS7_ENCRYPTED_DATA)

        return SECFailure;

    algid = SEC_PKCS7GetEncryptionAlgorithm(cinfo);

    if (algid == NULL)

        return SECFailure;

    if (poolp == NULL)

        poolp = cinfo->poolp;

    mark = PORT_ArenaMark(poolp);

    src = &cinfo->content.encryptedData->encContentInfo.encContent;

    dest = &cinfo->content.encryptedData->encContentInfo.plainContent;

    dest->data = (unsigned char *)PORT_ArenaZAlloc(poolp, (src->len + 64));

    dest->len = (src->len + 64);

    if (dest->data == NULL) {

        rv = SECFailure;

        goto loser;

    }

    slot = PK11_GetInternalKeySlot();

    if (slot == NULL) {

        rv = SECFailure;

        goto loser;

    }

    eKey = PK11_PBEKeyGen(slot, algid, key, PR_FALSE, wincx);

    if (eKey == NULL) {

        rv = SECFailure;

        goto loser;

    }

    cryptoMechType = PK11_GetPBECryptoMechanism(algid, &c_param, key);

    if (cryptoMechType == CKM_INVALID_MECHANISM) {

        rv = SECFailure;

        goto loser;

    }

    cx = PK11_CreateContextBySymKey(cryptoMechType, CKA_DECRYPT,

                                    eKey, c_param);

    if (cx == NULL) {

        rv = SECFailure;

        goto loser;

    }

    rv = PK11_CipherOp((PK11Context *)cx, dest->data, (int *)(&dest->len),

                       (int)(src->len + 64), src->data, (int)src->len);

    PK11_DestroyContext((PK11Context *)cx, PR_TRUE);

    /* PK11_CipherOp may leave dest->len at 0; bail out before the padding

     * check so dest->len - 1 does not underflow. */

    if (rv != SECSuccess) {

        goto loser;

    }

    bs = PK11_GetBlockSize(cryptoMechType, c_param);

    if (bs) {

        /* Check for proper PKCS#7 padding: the last byte gives the number of

         * pad bytes, which must be in [1, bs]. */

        unsigned int pad = dest->data[dest->len - 1];

        if ((dest->len >= (unsigned int)bs) &&

            pad >= 1 && pad <= (unsigned int)bs) {

            dest->len -= pad;

        } else {

            rv = SECFailure;

            /* set an error ? */

        }

    }

loser:

    /* let success fall through */

    if (rv == SECFailure)

        PORT_ArenaRelease(poolp, mark);

    else

        PORT_ArenaUnmark(poolp, mark);

    if (eKey != NULL)

        PK11_FreeSymKey(eKey);

    if (slot != NULL)

        PK11_FreeSlot(slot);

    if (c_param != NULL)

        SECITEM_ZfreeItem(c_param, PR_TRUE);

    return rv;

}

SECItem **

SEC_PKCS7GetCertificateList(SEC_PKCS7ContentInfo *cinfo)

{

    switch (SEC_PKCS7ContentType(cinfo)) {

        case SEC_OID_PKCS7_SIGNED_DATA:

            return cinfo->content.signedData->rawCerts;

            break;

        default:

            return NULL;

            break;

    }

}