/*
* NSS_CMSEncryptedData_Decode_BeforeData - find bulk key & set up decryption
*/
SECStatus
NSS_CMSEncryptedData_Decode_BeforeData(NSSCMSEncryptedData *encd)
{
PK11SymKey *bulkkey = NULL;
NSSCMSContentInfo *cinfo;
SECAlgorithmID *bulkalg;
SECStatus rv = SECFailure;
cinfo = &(encd->contentInfo);
bulkalg = NSS_CMSContentInfo_GetContentEncAlg(cinfo);
if (encd->cmsg->decrypt_key_cb == NULL) /* no callback? no key../ */
goto loser;
bulkkey = (*encd->cmsg->decrypt_key_cb)(encd->cmsg->decrypt_key_cb_arg, bulkalg);
if (bulkkey == NULL)
/* no success finding a bulk key */
goto loser;
NSS_CMSContentInfo_SetBulkKey(cinfo, bulkkey);
cinfo->ciphcx = NSS_CMSCipherContext_StartDecrypt(bulkkey, bulkalg);
if (cinfo->ciphcx == NULL)
goto loser; /* error has been set by NSS_CMSCipherContext_StartDecrypt */
/* we are done with (this) bulkkey now. */
PK11_FreeSymKey(bulkkey);
rv = SECSuccess;
loser:
return rv;
}
/*
* NSS_CMSEncryptedData_Encode_BeforeData - set up encryption
*/
SECStatus
NSS_CMSEncryptedData_Encode_BeforeData(NSSCMSEncryptedData *encd)
{
NSSCMSContentInfo *cinfo;
PK11SymKey *bulkkey;
SECAlgorithmID *algid;
cinfo = &(encd->contentInfo);
/* find bulkkey and algorithm - must have been set by NSS_CMSEncryptedData_Encode_BeforeStart */
bulkkey = NSS_CMSContentInfo_GetBulkKey(cinfo);
if (bulkkey == NULL)
return SECFailure;
algid = NSS_CMSContentInfo_GetContentEncAlg(cinfo);
if (algid == NULL)
return SECFailure;
/* this may modify algid (with IVs generated in a token).
* it is therefore essential that algid is a pointer to the "real" contentEncAlg,
* not just to a copy */
cinfo->ciphcx = NSS_CMSCipherContext_StartEncrypt(encd->cmsg->poolp, bulkkey, algid);
PK11_FreeSymKey(bulkkey);
if (cinfo->ciphcx == NULL)
return SECFailure;
return SECSuccess;
}
/*
* NSS_CMSEncryptedData_Encode_BeforeStart - do all the necessary things to a EncryptedData
* before encoding begins.
*
* In particular:
* - set the correct version value.
* - get the encryption key
*/
SECStatus
NSS_CMSEncryptedData_Encode_BeforeStart(NSSCMSEncryptedData *encd)
{
int version;
PK11SymKey *bulkkey = NULL;
SECItem *dummy;
NSSCMSContentInfo *cinfo = &(encd->contentInfo);
if (NSS_CMSArray_IsEmpty((void **)encd->unprotectedAttr))
version = NSS_CMS_ENCRYPTED_DATA_VERSION;
else
version = NSS_CMS_ENCRYPTED_DATA_VERSION_UPATTR;
dummy = SEC_ASN1EncodeInteger (encd->cmsg->poolp, &(encd->version), version);
if (dummy == NULL)
return SECFailure;
/* now get content encryption key (bulk key) by using our cmsg callback */
if (encd->cmsg->decrypt_key_cb)
bulkkey = (*encd->cmsg->decrypt_key_cb)(encd->cmsg->decrypt_key_cb_arg,
NSS_CMSContentInfo_GetContentEncAlg(cinfo));
if (bulkkey == NULL)
return SECFailure;
/* store the bulk key in the contentInfo so that the encoder can find it */
NSS_CMSContentInfo_SetBulkKey(cinfo, bulkkey);
PK11_FreeSymKey (bulkkey);
return SECSuccess;
}
/*
* NSS_CMSEnvelopedData_Encode_BeforeData - set up encryption
*
* it is essential that this is called before the contentEncAlg is encoded, because
* setting up the encryption may generate IVs and thus change it!
*/
SECStatus
NSS_CMSEnvelopedData_Encode_BeforeData(NSSCMSEnvelopedData *envd)
{
NSSCMSContentInfo *cinfo;
PK11SymKey *bulkkey;
SECAlgorithmID *algid;
SECStatus rv;
cinfo = &(envd->contentInfo);
/* find bulkkey and algorithm - must have been set by NSS_CMSEnvelopedData_Encode_BeforeStart */
bulkkey = NSS_CMSContentInfo_GetBulkKey(cinfo);
if (bulkkey == NULL)
return SECFailure;
algid = NSS_CMSContentInfo_GetContentEncAlg(cinfo);
if (algid == NULL)
return SECFailure;
rv = NSS_CMSContentInfo_Private_Init(cinfo);
if (rv != SECSuccess) {
return SECFailure;
}
/* this may modify algid (with IVs generated in a token).
* it is essential that algid is a pointer to the contentEncAlg data, not a
* pointer to a copy! */
cinfo->privateInfo->ciphcx = NSS_CMSCipherContext_StartEncrypt(envd->cmsg->poolp, bulkkey, algid);
PK11_FreeSymKey(bulkkey);
if (cinfo->privateInfo->ciphcx == NULL)
return SECFailure;
return SECSuccess;
}
/*
* NSS_CMSEnvelopedData_Decode_BeforeData - find our recipientinfo,
* derive bulk key & set up our contentinfo
*/
SECStatus
NSS_CMSEnvelopedData_Decode_BeforeData(NSSCMSEnvelopedData *envd)
{
NSSCMSRecipientInfo *ri;
PK11SymKey *bulkkey = NULL;
SECOidTag bulkalgtag;
SECAlgorithmID *bulkalg;
SECStatus rv = SECFailure;
NSSCMSContentInfo *cinfo;
NSSCMSRecipient **recipient_list = NULL;
NSSCMSRecipient *recipient;
int rlIndex;
if (NSS_CMSArray_Count((void **)envd->recipientInfos) == 0) {
PORT_SetError(SEC_ERROR_BAD_DATA);
#if 0
PORT_SetErrorString("No recipient data in envelope.");
#endif
goto loser;
}
/* look if one of OUR cert's issuerSN is on the list of recipients, and if so, */
/* get the cert and private key for it right away */
recipient_list = nss_cms_recipient_list_create(envd->recipientInfos);
if (recipient_list == NULL)
goto loser;
/* what about multiple recipientInfos that match?
* especially if, for some reason, we could not produce a bulk key with the first match?!
* we could loop & feed partial recipient_list to PK11_FindCertAndKeyByRecipientList...
* maybe later... */
rlIndex = PK11_FindCertAndKeyByRecipientListNew(recipient_list, envd->cmsg->pwfn_arg);
/* if that fails, then we're not an intended recipient and cannot decrypt */
if (rlIndex < 0) {
PORT_SetError(SEC_ERROR_NOT_A_RECIPIENT);
#if 0
PORT_SetErrorString("Cannot decrypt data because proper key cannot be found.");
#endif
goto loser;
}
recipient = recipient_list[rlIndex];
if (!recipient->cert || !recipient->privkey) {
/* XXX should set an error code ?!? */
goto loser;
}
/* get a pointer to "our" recipientinfo */
ri = envd->recipientInfos[recipient->riIndex];
cinfo = &(envd->contentInfo);
bulkalgtag = NSS_CMSContentInfo_GetContentEncAlgTag(cinfo);
if (bulkalgtag == SEC_OID_UNKNOWN) {
PORT_SetError(SEC_ERROR_INVALID_ALGORITHM);
} else
bulkkey =
NSS_CMSRecipientInfo_UnwrapBulkKey(ri,recipient->subIndex,
recipient->cert,
recipient->privkey,
bulkalgtag);
if (bulkkey == NULL) {
/* no success finding a bulk key */
goto loser;
}
NSS_CMSContentInfo_SetBulkKey(cinfo, bulkkey);
bulkalg = NSS_CMSContentInfo_GetContentEncAlg(cinfo);
rv = NSS_CMSContentInfo_Private_Init(cinfo);
if (rv != SECSuccess) {
goto loser;
}
rv = SECFailure;
cinfo->privateInfo->ciphcx = NSS_CMSCipherContext_StartDecrypt(bulkkey, bulkalg);
if (cinfo->privateInfo->ciphcx == NULL)
goto loser; /* error has been set by NSS_CMSCipherContext_StartDecrypt */
rv = SECSuccess;
loser:
if (bulkkey)
PK11_FreeSymKey(bulkkey);
if (recipient_list != NULL)
nss_cms_recipient_list_destroy(recipient_list);
return rv;
}
