/* 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 message methods.

 */

#include "cmslocal.h"

#include "cert.h"

#include "secasn1.h"

#include "secitem.h"

#include "secoid.h"

#include "pk11func.h"

#include "secerr.h"

/*

 * NSS_CMSMessage_Create - create a CMS message object

 *

 * "poolp" - arena to allocate memory from, or NULL if new arena should be created

 */

NSSCMSMessage *

NSS_CMSMessage_Create(PLArenaPool *poolp)

{

    void *mark = NULL;

    NSSCMSMessage *cmsg;

    PRBool poolp_is_ours = PR_FALSE;

    if (poolp == NULL) {

        poolp = PORT_NewArena(1024); /* XXX what is right value? */

        if (poolp == NULL)

            return NULL;

        poolp_is_ours = PR_TRUE;

    }

    if (!poolp_is_ours)

        mark = PORT_ArenaMark(poolp);

    cmsg = (NSSCMSMessage *)PORT_ArenaZAlloc(poolp, sizeof(NSSCMSMessage));

    if (cmsg == NULL ||

        NSS_CMSContentInfo_Private_Init(&(cmsg->contentInfo)) != SECSuccess) {

        if (!poolp_is_ours) {

            if (mark) {

                PORT_ArenaRelease(poolp, mark);

            }

        } else

            PORT_FreeArena(poolp, PR_FALSE);

        return NULL;

    }

    cmsg->poolp = poolp;

    cmsg->poolp_is_ours = poolp_is_ours;

    cmsg->refCount = 1;

    if (mark)

        PORT_ArenaUnmark(poolp, mark);

    return cmsg;

}

/*

 * NSS_CMSMessage_SetEncodingParams - set up a CMS message object for encoding or decoding

 *

 * "cmsg" - message object

 * "pwfn", pwfn_arg" - callback function for getting token password

 * "decrypt_key_cb", "decrypt_key_cb_arg" - callback function for getting bulk key for encryptedData

 * "detached_digestalgs", "detached_digests" - digests from detached content

 */

void

NSS_CMSMessage_SetEncodingParams(NSSCMSMessage *cmsg,

                                 PK11PasswordFunc pwfn, void *pwfn_arg,

                                 NSSCMSGetDecryptKeyCallback decrypt_key_cb, void *decrypt_key_cb_arg,

                                 SECAlgorithmID **detached_digestalgs, SECItem **detached_digests)

{

    if (pwfn)

        PK11_SetPasswordFunc(pwfn);

    cmsg->pwfn_arg = pwfn_arg;

    cmsg->decrypt_key_cb = decrypt_key_cb;

    cmsg->decrypt_key_cb_arg = decrypt_key_cb_arg;

    cmsg->detached_digestalgs = detached_digestalgs;

    cmsg->detached_digests = detached_digests;

}

/*

 * NSS_CMSMessage_Destroy - destroy a CMS message and all of its sub-pieces.

 */

void

NSS_CMSMessage_Destroy(NSSCMSMessage *cmsg)

{

    PORT_Assert(cmsg->refCount > 0);

    if (cmsg->refCount <= 0) /* oops */

        return;

    cmsg->refCount--; /* thread safety? */

    if (cmsg->refCount > 0)

        return;

    NSS_CMSContentInfo_Destroy(&(cmsg->contentInfo));

    /* if poolp is not NULL, cmsg is the owner of its arena */

    if (cmsg->poolp_is_ours)

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

}

/*

 * NSS_CMSMessage_Copy - return a copy of the given message.

 *

 * The copy may be virtual or may be real -- either way, the result needs

 * to be passed to NSS_CMSMessage_Destroy later (as does the original).

 */

NSSCMSMessage *

NSS_CMSMessage_Copy(NSSCMSMessage *cmsg)

{

    if (cmsg == NULL)

        return NULL;

    PORT_Assert(cmsg->refCount > 0);

    cmsg->refCount++; /* XXX chrisk thread safety? */

    return cmsg;

}

/*

 * NSS_CMSMessage_GetArena - return a pointer to the message's arena pool

 */

PLArenaPool *

NSS_CMSMessage_GetArena(NSSCMSMessage *cmsg)

{

    return cmsg->poolp;

}

/*

 * NSS_CMSMessage_GetContentInfo - return a pointer to the top level contentInfo

 */

NSSCMSContentInfo *

NSS_CMSMessage_GetContentInfo(NSSCMSMessage *cmsg)

{

    return &(cmsg->contentInfo);

}

/*

 * Return a pointer to the actual content.

 * In the case of those types which are encrypted, this returns the *plain* content.

 * In case of nested contentInfos, this descends and retrieves the innermost content.

 */

SECItem *

NSS_CMSMessage_GetContent(NSSCMSMessage *cmsg)

{

    /* this is a shortcut */

    NSSCMSContentInfo *cinfo = NSS_CMSMessage_GetContentInfo(cmsg);

    SECItem *pItem = NSS_CMSContentInfo_GetInnerContent(cinfo);

    return pItem;

}

/*

 * NSS_CMSMessage_ContentLevelCount - count number of levels of CMS content objects in this message

 *

 * CMS data content objects do not count.

 */

int

NSS_CMSMessage_ContentLevelCount(NSSCMSMessage *cmsg)

{

    int count = 0;

    NSSCMSContentInfo *cinfo;

    /* walk down the chain of contentinfos */

    for (cinfo = &(cmsg->contentInfo); cinfo != NULL;) {

        count++;

        cinfo = NSS_CMSContentInfo_GetChildContentInfo(cinfo);

    }

    return count;

}

/*

 * NSS_CMSMessage_ContentLevel - find content level #n

 *

 * CMS data content objects do not count.

 */

NSSCMSContentInfo *

NSS_CMSMessage_ContentLevel(NSSCMSMessage *cmsg, int n)

{

    int count = 0;

    NSSCMSContentInfo *cinfo;

    /* walk down the chain of contentinfos */

    for (cinfo = &(cmsg->contentInfo); cinfo != NULL && count < n;

         cinfo = NSS_CMSContentInfo_GetChildContentInfo(cinfo)) {

        count++;

    }

    return cinfo;

}

/*

 * NSS_CMSMessage_ContainsCertsOrCrls - see if message contains certs along the way

 */

PRBool

NSS_CMSMessage_ContainsCertsOrCrls(NSSCMSMessage *cmsg)

{

    NSSCMSContentInfo *cinfo;

    /* descend into CMS message */

    for (cinfo = &(cmsg->contentInfo); cinfo != NULL;

         cinfo = NSS_CMSContentInfo_GetChildContentInfo(cinfo)) {

        if (!NSS_CMSType_IsData(NSS_CMSContentInfo_GetContentTypeTag(cinfo)))

            continue; /* next level */

        if (NSS_CMSSignedData_ContainsCertsOrCrls(cinfo->content.signedData))

            return PR_TRUE;

        /* callback here for generic wrappers? */

    }

    return PR_FALSE;

}

/*

 * NSS_CMSMessage_IsEncrypted - see if message contains a encrypted submessage

 */

PRBool

NSS_CMSMessage_IsEncrypted(NSSCMSMessage *cmsg)

{

    NSSCMSContentInfo *cinfo;

    /* walk down the chain of contentinfos */

    for (cinfo = &(cmsg->contentInfo); cinfo != NULL;

         cinfo = NSS_CMSContentInfo_GetChildContentInfo(cinfo)) {

        switch (NSS_CMSContentInfo_GetContentTypeTag(cinfo)) {

            case SEC_OID_PKCS7_ENVELOPED_DATA:

            case SEC_OID_PKCS7_ENCRYPTED_DATA:

                return PR_TRUE;

            default:

                /* callback here for generic wrappers? */

                break;

        }

    }

    return PR_FALSE;

}

/*

 * NSS_CMSMessage_IsSigned - see if message contains a signed submessage

 *

 * If the CMS message has a SignedData with a signature (not just a SignedData)

 * return true; false otherwise.  This can/should be called before calling

 * VerifySignature, which will always indicate failure if no signature is

 * present, but that does not mean there even was a signature!

 * Note that the content itself can be empty (detached content was sent

 * another way); it is the presence of the signature that matters.

 */

PRBool

NSS_CMSMessage_IsSigned(NSSCMSMessage *cmsg)

{

    NSSCMSContentInfo *cinfo;

    /* walk down the chain of contentinfos */

    for (cinfo = &(cmsg->contentInfo); cinfo != NULL;

         cinfo = NSS_CMSContentInfo_GetChildContentInfo(cinfo)) {

        switch (NSS_CMSContentInfo_GetContentTypeTag(cinfo)) {

            case SEC_OID_PKCS7_SIGNED_DATA:

                if (!NSS_CMSArray_IsEmpty((void **)cinfo->content.signedData->signerInfos))

                    return PR_TRUE;

                break;

            default:

                /* callback here for generic wrappers? */

                break;

        }

    }

    return PR_FALSE;

}

/*

 * NSS_CMSMessage_IsContentEmpty - see if content is empty

 *

 * returns PR_TRUE is innermost content length is < minLen

 * XXX need the encrypted content length (why?)

 */

PRBool

NSS_CMSMessage_IsContentEmpty(NSSCMSMessage *cmsg, unsigned int minLen)

{

    SECItem *item = NULL;

    if (cmsg == NULL)

        return PR_TRUE;

    item = NSS_CMSContentInfo_GetContent(NSS_CMSMessage_GetContentInfo(cmsg));

    if (!item) {

        return PR_TRUE;

    } else if (item->len <= minLen) {

        return PR_TRUE;

    }

    return PR_FALSE;

}