/* 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 recipientInfo methods.
*/
#include "cmslocal.h"
#include "cert.h"
#include "key.h"
#include "secasn1.h"
#include "secitem.h"
#include "secoid.h"
#include "pk11func.h"
#include "secerr.h"
PRBool
nss_cmsrecipientinfo_usessubjectkeyid(NSSCMSRecipientInfo *ri)
{
if (ri->recipientInfoType == NSSCMSRecipientInfoID_KeyTrans) {
NSSCMSRecipientIdentifier *rid;
rid = &ri->ri.keyTransRecipientInfo.recipientIdentifier;
if (rid->identifierType == NSSCMSRecipientID_SubjectKeyID) {
return PR_TRUE;
}
}
return PR_FALSE;
}
/*
* NOTE: fakeContent marks CMSMessage structure which is only used as a carrier
* of pwfn_arg and arena pools. In an ideal world, NSSCMSMessage would not have
* been exported, and we would have added an ordinary enum to handle this
* check. Unfortunatly wo don't have that luxury so we are overloading the
* contentTypeTag field. NO code should every try to interpret this content tag
* as a real OID tag, or use any fields other than pwfn_arg or poolp of this
* CMSMessage for that matter */
static const SECOidData fakeContent;
NSSCMSRecipientInfo *
nss_cmsrecipientinfo_create(NSSCMSMessage *cmsg,
NSSCMSRecipientIDSelector type,
CERTCertificate *cert,
SECKEYPublicKey *pubKey,
SECItem *subjKeyID,
void* pwfn_arg,
SECItem* DERinput)
{
NSSCMSRecipientInfo *ri;
void *mark;
SECOidTag certalgtag;
SECStatus rv = SECSuccess;
NSSCMSRecipientEncryptedKey *rek;
NSSCMSOriginatorIdentifierOrKey *oiok;
unsigned long version;
SECItem *dummy;
PLArenaPool *poolp;
CERTSubjectPublicKeyInfo *spki, *freeSpki = NULL;
NSSCMSRecipientIdentifier *rid;
extern const SEC_ASN1Template NSSCMSRecipientInfoTemplate[];
if (!cmsg) {
/* a CMSMessage wasn't supplied, create a fake one to hold the pwfunc
* and a private arena pool */
cmsg = NSS_CMSMessage_Create(NULL);
cmsg->pwfn_arg = pwfn_arg;
/* mark it as a special cms message */
cmsg->contentInfo.contentTypeTag = (SECOidData *)&fakeContent;
}
poolp = cmsg->poolp;
mark = PORT_ArenaMark(poolp);
ri = (NSSCMSRecipientInfo *)PORT_ArenaZAlloc(poolp, sizeof(NSSCMSRecipientInfo));
if (ri == NULL)
goto loser;
ri->cmsg = cmsg;
if (DERinput) {
/* decode everything from DER */
SECItem newinput;
SECStatus rv = SECITEM_CopyItem(poolp, &newinput, DERinput);
if (SECSuccess != rv)
goto loser;
rv = SEC_QuickDERDecodeItem(poolp, ri, NSSCMSRecipientInfoTemplate, &newinput);
if (SECSuccess != rv)
goto loser;
}
switch (type) {
case NSSCMSRecipientID_IssuerSN:
{
ri->cert = CERT_DupCertificate(cert);
if (NULL == ri->cert)
goto loser;
spki = &(cert->subjectPublicKeyInfo);
break;
}
case NSSCMSRecipientID_SubjectKeyID:
{
PORT_Assert(pubKey);
spki = freeSpki = SECKEY_CreateSubjectPublicKeyInfo(pubKey);
break;
}
case NSSCMSRecipientID_BrandNew:
goto done;
break;
default:
/* unkown type */
goto loser;
break;
}
certalgtag = SECOID_GetAlgorithmTag(&(spki->algorithm));
rid = &ri->ri.keyTransRecipientInfo.recipientIdentifier;
switch (certalgtag) {
case SEC_OID_PKCS1_RSA_ENCRYPTION:
ri->recipientInfoType = NSSCMSRecipientInfoID_KeyTrans;
rid->identifierType = type;
if (type == NSSCMSRecipientID_IssuerSN) {
rid->id.issuerAndSN = CERT_GetCertIssuerAndSN(poolp, cert);
if (rid->id.issuerAndSN == NULL) {
break;
}
} else if (type == NSSCMSRecipientID_SubjectKeyID){
NSSCMSKeyTransRecipientInfoEx *riExtra;
rid->id.subjectKeyID = PORT_ArenaNew(poolp, SECItem);
if (rid->id.subjectKeyID == NULL) {
rv = SECFailure;
PORT_SetError(SEC_ERROR_NO_MEMORY);
break;
}
SECITEM_CopyItem(poolp, rid->id.subjectKeyID, subjKeyID);
if (rid->id.subjectKeyID->data == NULL) {
rv = SECFailure;
PORT_SetError(SEC_ERROR_NO_MEMORY);
break;
}
riExtra = &ri->ri.keyTransRecipientInfoEx;
riExtra->version = 0;
riExtra->pubKey = SECKEY_CopyPublicKey(pubKey);
if (riExtra->pubKey == NULL) {
rv = SECFailure;
PORT_SetError(SEC_ERROR_NO_MEMORY);
break;
}
} else {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
rv = SECFailure;
}
break;
case SEC_OID_X942_DIFFIE_HELMAN_KEY: /* dh-public-number */
PORT_Assert(type == NSSCMSRecipientID_IssuerSN);
if (type != NSSCMSRecipientID_IssuerSN) {
rv = SECFailure;
break;
}
/* a key agreement op */
ri->recipientInfoType = NSSCMSRecipientInfoID_KeyAgree;
if (ri->ri.keyTransRecipientInfo.recipientIdentifier.id.issuerAndSN == NULL) {
rv = SECFailure;
break;
}
/* we do not support the case where multiple recipients
* share the same KeyAgreeRecipientInfo and have multiple RecipientEncryptedKeys
* in this case, we would need to walk all the recipientInfos, take the
* ones that do KeyAgreement algorithms and join them, algorithm by algorithm
* Then, we'd generate ONE ukm and OriginatorIdentifierOrKey */
/* only epheremal-static Diffie-Hellman is supported for now
* this is the only form of key agreement that provides potential anonymity
* of the sender, plus we do not have to include certs in the message */
/* force single recipientEncryptedKey for now */
if ((rek = NSS_CMSRecipientEncryptedKey_Create(poolp)) == NULL) {
rv = SECFailure;
break;
}
/* hardcoded IssuerSN choice for now */
rek->recipientIdentifier.identifierType = NSSCMSKeyAgreeRecipientID_IssuerSN;
if ((rek->recipientIdentifier.id.issuerAndSN = CERT_GetCertIssuerAndSN(poolp, cert)) == NULL) {
rv = SECFailure;
break;
}
oiok = &(ri->ri.keyAgreeRecipientInfo.originatorIdentifierOrKey);
/* see RFC2630 12.3.1.1 */
oiok->identifierType = NSSCMSOriginatorIDOrKey_OriginatorPublicKey;
rv = NSS_CMSArray_Add(poolp, (void ***)&ri->ri.keyAgreeRecipientInfo.recipientEncryptedKeys,
(void *)rek);
break;
default:
/* other algorithms not supported yet */
/* NOTE that we do not support any KEK algorithm */
PORT_SetError(SEC_ERROR_INVALID_ALGORITHM);
rv = SECFailure;
break;
}
if (rv == SECFailure)
goto loser;
/* set version */
switch (ri->recipientInfoType) {
case NSSCMSRecipientInfoID_KeyTrans:
if (ri->ri.keyTransRecipientInfo.recipientIdentifier.identifierType == NSSCMSRecipientID_IssuerSN)
version = NSS_CMS_KEYTRANS_RECIPIENT_INFO_VERSION_ISSUERSN;
else
version = NSS_CMS_KEYTRANS_RECIPIENT_INFO_VERSION_SUBJKEY;
dummy = SEC_ASN1EncodeInteger(poolp, &(ri->ri.keyTransRecipientInfo.version), version);
if (dummy == NULL)
goto loser;
break;
case NSSCMSRecipientInfoID_KeyAgree:
dummy = SEC_ASN1EncodeInteger(poolp, &(ri->ri.keyAgreeRecipientInfo.version),
NSS_CMS_KEYAGREE_RECIPIENT_INFO_VERSION);
if (dummy == NULL)
goto loser;
break;
case NSSCMSRecipientInfoID_KEK:
/* NOTE: this cannot happen as long as we do not support any KEK algorithm */
dummy = SEC_ASN1EncodeInteger(poolp, &(ri->ri.kekRecipientInfo.version),
NSS_CMS_KEK_RECIPIENT_INFO_VERSION);
if (dummy == NULL)
goto loser;
break;
}
done:
PORT_ArenaUnmark (poolp, mark);
if (freeSpki)
SECKEY_DestroySubjectPublicKeyInfo(freeSpki);
return ri;
loser:
if (ri && ri->cert) {
CERT_DestroyCertificate(ri->cert);
}
if (freeSpki) {
SECKEY_DestroySubjectPublicKeyInfo(freeSpki);
}
PORT_ArenaRelease (poolp, mark);
if (cmsg->contentInfo.contentTypeTag == &fakeContent) {
NSS_CMSMessage_Destroy(cmsg);
}
return NULL;
}
/*
* NSS_CMSRecipientInfo_Create - create a recipientinfo
*
* we currently do not create KeyAgreement recipientinfos with multiple
* recipientEncryptedKeys the certificate is supposed to have been
* verified by the caller
*/
NSSCMSRecipientInfo *
NSS_CMSRecipientInfo_Create(NSSCMSMessage *cmsg, CERTCertificate *cert)
{
return nss_cmsrecipientinfo_create(cmsg, NSSCMSRecipientID_IssuerSN, cert,
NULL, NULL, NULL, NULL);
}
NSSCMSRecipientInfo *
NSS_CMSRecipientInfo_CreateNew(void* pwfn_arg)
{
return nss_cmsrecipientinfo_create(NULL, NSSCMSRecipientID_BrandNew, NULL,
NULL, NULL, pwfn_arg, NULL);
}
NSSCMSRecipientInfo *
NSS_CMSRecipientInfo_CreateFromDER(SECItem* input, void* pwfn_arg)
{
return nss_cmsrecipientinfo_create(NULL, NSSCMSRecipientID_BrandNew, NULL,
NULL, NULL, pwfn_arg, input);
}
NSSCMSRecipientInfo *
NSS_CMSRecipientInfo_CreateWithSubjKeyID(NSSCMSMessage *cmsg,
SECItem *subjKeyID,
SECKEYPublicKey *pubKey)
{
return nss_cmsrecipientinfo_create(cmsg, NSSCMSRecipientID_SubjectKeyID,
NULL, pubKey, subjKeyID, NULL, NULL);
}
NSSCMSRecipientInfo *
NSS_CMSRecipientInfo_CreateWithSubjKeyIDFromCert(NSSCMSMessage *cmsg,
CERTCertificate *cert)
{
SECKEYPublicKey *pubKey = NULL;
SECItem subjKeyID = {siBuffer, NULL, 0};
NSSCMSRecipientInfo *retVal = NULL;
if (!cmsg || !cert) {
return NULL;
}
pubKey = CERT_ExtractPublicKey(cert);
if (!pubKey) {
goto done;
}
if (CERT_FindSubjectKeyIDExtension(cert, &subjKeyID) != SECSuccess ||
subjKeyID.data == NULL) {
goto done;
}
retVal = NSS_CMSRecipientInfo_CreateWithSubjKeyID(cmsg, &subjKeyID, pubKey);
done:
if (pubKey)
SECKEY_DestroyPublicKey(pubKey);
if (subjKeyID.data)
SECITEM_FreeItem(&subjKeyID, PR_FALSE);
return retVal;
}
void
NSS_CMSRecipientInfo_Destroy(NSSCMSRecipientInfo *ri)
{
if (!ri) {
return;
}
/* version was allocated on the pool, so no need to destroy it */
/* issuerAndSN was allocated on the pool, so no need to destroy it */
if (ri->cert != NULL)
CERT_DestroyCertificate(ri->cert);
if (nss_cmsrecipientinfo_usessubjectkeyid(ri)) {
NSSCMSKeyTransRecipientInfoEx *extra;
extra = &ri->ri.keyTransRecipientInfoEx;
if (extra->pubKey)
SECKEY_DestroyPublicKey(extra->pubKey);
}
if (ri->cmsg && ri->cmsg->contentInfo.contentTypeTag == &fakeContent) {
NSS_CMSMessage_Destroy(ri->cmsg);
}
/* we're done. */
}
int
NSS_CMSRecipientInfo_GetVersion(NSSCMSRecipientInfo *ri)
{
unsigned long version;
SECItem *versionitem = NULL;
switch (ri->recipientInfoType) {
case NSSCMSRecipientInfoID_KeyTrans:
/* ignore subIndex */
versionitem = &(ri->ri.keyTransRecipientInfo.version);
break;
case NSSCMSRecipientInfoID_KEK:
/* ignore subIndex */
versionitem = &(ri->ri.kekRecipientInfo.version);
break;
case NSSCMSRecipientInfoID_KeyAgree:
versionitem = &(ri->ri.keyAgreeRecipientInfo.version);
break;
}
PORT_Assert(versionitem);
if (versionitem == NULL)
return 0;
/* always take apart the SECItem */
if (SEC_ASN1DecodeInteger(versionitem, &version) != SECSuccess)
return 0;
else
return (int)version;
}
SECItem *
NSS_CMSRecipientInfo_GetEncryptedKey(NSSCMSRecipientInfo *ri, int subIndex)
{
SECItem *enckey = NULL;
switch (ri->recipientInfoType) {
case NSSCMSRecipientInfoID_KeyTrans:
/* ignore subIndex */
enckey = &(ri->ri.keyTransRecipientInfo.encKey);
break;
case NSSCMSRecipientInfoID_KEK:
/* ignore subIndex */
enckey = &(ri->ri.kekRecipientInfo.encKey);
break;
case NSSCMSRecipientInfoID_KeyAgree:
enckey = &(ri->ri.keyAgreeRecipientInfo.recipientEncryptedKeys[subIndex]->encKey);
break;
}
return enckey;
}
SECOidTag
NSS_CMSRecipientInfo_GetKeyEncryptionAlgorithmTag(NSSCMSRecipientInfo *ri)
{
SECOidTag encalgtag = SEC_OID_UNKNOWN; /* an invalid encryption alg */
switch (ri->recipientInfoType) {
case NSSCMSRecipientInfoID_KeyTrans:
encalgtag = SECOID_GetAlgorithmTag(&(ri->ri.keyTransRecipientInfo.keyEncAlg));
break;
case NSSCMSRecipientInfoID_KeyAgree:
encalgtag = SECOID_GetAlgorithmTag(&(ri->ri.keyAgreeRecipientInfo.keyEncAlg));
break;
case NSSCMSRecipientInfoID_KEK:
encalgtag = SECOID_GetAlgorithmTag(&(ri->ri.kekRecipientInfo.keyEncAlg));
break;
}
return encalgtag;
}
SECStatus
NSS_CMSRecipientInfo_WrapBulkKey(NSSCMSRecipientInfo *ri, PK11SymKey *bulkkey,
SECOidTag bulkalgtag)
{
CERTCertificate *cert;
SECOidTag certalgtag;
SECStatus rv = SECSuccess;
NSSCMSRecipientEncryptedKey *rek;
NSSCMSOriginatorIdentifierOrKey *oiok;
CERTSubjectPublicKeyInfo *spki, *freeSpki = NULL;
PLArenaPool *poolp;
NSSCMSKeyTransRecipientInfoEx *extra = NULL;
PRBool usesSubjKeyID;
poolp = ri->cmsg->poolp;
cert = ri->cert;
usesSubjKeyID = nss_cmsrecipientinfo_usessubjectkeyid(ri);
if (cert) {
spki = &cert->subjectPublicKeyInfo;
certalgtag = SECOID_GetAlgorithmTag(&(spki->algorithm));
} else if (usesSubjKeyID) {
extra = &ri->ri.keyTransRecipientInfoEx;
/* sanity check */
PORT_Assert(extra->pubKey);
if (!extra->pubKey) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
spki = freeSpki = SECKEY_CreateSubjectPublicKeyInfo(extra->pubKey);
certalgtag = SECOID_GetAlgorithmTag(&spki->algorithm);
} else {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
/* XXX set ri->recipientInfoType to the proper value here */
/* or should we look if it's been set already ? */
certalgtag = SECOID_GetAlgorithmTag(&spki->algorithm);
switch (certalgtag) {
case SEC_OID_PKCS1_RSA_ENCRYPTION:
/* wrap the symkey */
if (cert) {
rv = NSS_CMSUtil_EncryptSymKey_RSA(poolp, cert, bulkkey,
&ri->ri.keyTransRecipientInfo.encKey);
if (rv != SECSuccess)
break;
} else if (usesSubjKeyID) {
PORT_Assert(extra != NULL);
rv = NSS_CMSUtil_EncryptSymKey_RSAPubKey(poolp, extra->pubKey,
bulkkey, &ri->ri.keyTransRecipientInfo.encKey);
if (rv != SECSuccess)
break;
}
rv = SECOID_SetAlgorithmID(poolp, &(ri->ri.keyTransRecipientInfo.keyEncAlg), certalgtag, NULL);
break;
case SEC_OID_X942_DIFFIE_HELMAN_KEY: /* dh-public-number */
rek = ri->ri.keyAgreeRecipientInfo.recipientEncryptedKeys[0];
if (rek == NULL) {
rv = SECFailure;
break;
}
oiok = &(ri->ri.keyAgreeRecipientInfo.originatorIdentifierOrKey);
PORT_Assert(oiok->identifierType == NSSCMSOriginatorIDOrKey_OriginatorPublicKey);
/* see RFC2630 12.3.1.1 */
if (SECOID_SetAlgorithmID(poolp, &oiok->id.originatorPublicKey.algorithmIdentifier,
SEC_OID_X942_DIFFIE_HELMAN_KEY, NULL) != SECSuccess) {
rv = SECFailure;
break;
}
/* this will generate a key pair, compute the shared secret, */
/* derive a key and ukm for the keyEncAlg out of it, encrypt the bulk key with */
/* the keyEncAlg, set encKey, keyEncAlg, publicKey etc. */
rv = NSS_CMSUtil_EncryptSymKey_ESDH(poolp, cert, bulkkey,
&rek->encKey,
&ri->ri.keyAgreeRecipientInfo.ukm,
&ri->ri.keyAgreeRecipientInfo.keyEncAlg,
&oiok->id.originatorPublicKey.publicKey);
break;
default:
/* other algorithms not supported yet */
/* NOTE that we do not support any KEK algorithm */
PORT_SetError(SEC_ERROR_INVALID_ALGORITHM);
rv = SECFailure;
break;
}
if (freeSpki)
SECKEY_DestroySubjectPublicKeyInfo(freeSpki);
return rv;
}
PK11SymKey *
NSS_CMSRecipientInfo_UnwrapBulkKey(NSSCMSRecipientInfo *ri, int subIndex,
CERTCertificate *cert, SECKEYPrivateKey *privkey, SECOidTag bulkalgtag)
{
PK11SymKey *bulkkey = NULL;
SECAlgorithmID *encalg;
SECOidTag encalgtag;
SECItem *enckey;
int error;
ri->cert = CERT_DupCertificate(cert);
/* mark the recipientInfo so we can find it later */
switch (ri->recipientInfoType) {
case NSSCMSRecipientInfoID_KeyTrans:
encalg = &(ri->ri.keyTransRecipientInfo.keyEncAlg);
encalgtag = SECOID_GetAlgorithmTag(&(ri->ri.keyTransRecipientInfo.keyEncAlg));
enckey = &(ri->ri.keyTransRecipientInfo.encKey); /* ignore subIndex */
switch (encalgtag) {
case SEC_OID_PKCS1_RSA_ENCRYPTION:
/* RSA encryption algorithm: */
/* get the symmetric (bulk) key by unwrapping it using our private key */
bulkkey = NSS_CMSUtil_DecryptSymKey_RSA(privkey, enckey, bulkalgtag);
break;
default:
error = SEC_ERROR_UNSUPPORTED_KEYALG;
goto loser;
}
break;
case NSSCMSRecipientInfoID_KeyAgree:
encalg = &(ri->ri.keyAgreeRecipientInfo.keyEncAlg);
encalgtag = SECOID_GetAlgorithmTag(&(ri->ri.keyAgreeRecipientInfo.keyEncAlg));
enckey = &(ri->ri.keyAgreeRecipientInfo.recipientEncryptedKeys[subIndex]->encKey);
switch (encalgtag) {
case SEC_OID_X942_DIFFIE_HELMAN_KEY:
/* Diffie-Helman key exchange */
/* XXX not yet implemented */
/* XXX problem: SEC_OID_X942_DIFFIE_HELMAN_KEY points to a PKCS3 mechanism! */
/* we support ephemeral-static DH only, so if the recipientinfo */
/* has originator stuff in it, we punt (or do we? shouldn't be that hard...) */
/* first, we derive the KEK (a symkey!) using a Derive operation, then we get the */
/* content encryption key using a Unwrap op */
/* the derive operation has to generate the key using the algorithm in RFC2631 */
error = SEC_ERROR_UNSUPPORTED_KEYALG;
goto loser;
break;
default:
error = SEC_ERROR_UNSUPPORTED_KEYALG;
goto loser;
}
break;
case NSSCMSRecipientInfoID_KEK:
encalg = &(ri->ri.kekRecipientInfo.keyEncAlg);
encalgtag = SECOID_GetAlgorithmTag(&(ri->ri.kekRecipientInfo.keyEncAlg));
enckey = &(ri->ri.kekRecipientInfo.encKey);
/* not supported yet */
error = SEC_ERROR_UNSUPPORTED_KEYALG;
goto loser;
break;
}
/* XXXX continue here */
return bulkkey;
loser:
PORT_SetError(error);
return NULL;
}
SECStatus NSS_CMSRecipientInfo_GetCertAndKey(NSSCMSRecipientInfo *ri,
CERTCertificate** retcert,
SECKEYPrivateKey** retkey)
{
CERTCertificate* cert = NULL;
NSSCMSRecipient** recipients = NULL;
NSSCMSRecipientInfo* recipientInfos[2];
SECStatus rv = SECSuccess;
SECKEYPrivateKey* key = NULL;
if (!ri)
return SECFailure;
if (!retcert && !retkey) {
/* nothing requested, nothing found, success */
return SECSuccess;
}
if (retcert) {
*retcert = NULL;
}
if (retkey) {
*retkey = NULL;
}
if (ri->cert) {
cert = CERT_DupCertificate(ri->cert);
if (!cert) {
rv = SECFailure;
}
}
if (SECSuccess == rv && !cert) {
/* we don't have the cert, we have to look for it */
/* first build an NSS_CMSRecipient */
recipientInfos[0] = ri;
recipientInfos[1] = NULL;
recipients = nss_cms_recipient_list_create(recipientInfos);
if (recipients) {
/* now look for the cert and key */
if (0 == PK11_FindCertAndKeyByRecipientListNew(recipients,
ri->cmsg->pwfn_arg)) {
cert = CERT_DupCertificate(recipients[0]->cert);
key = SECKEY_CopyPrivateKey(recipients[0]->privkey);
} else {
rv = SECFailure;
}
nss_cms_recipient_list_destroy(recipients);
}
else {
rv = SECFailure;
}
} else if (SECSuccess == rv && cert && retkey) {
/* we have the cert, we just need the key now */
key = PK11_FindPrivateKeyFromCert(cert->slot, cert, ri->cmsg->pwfn_arg);
}
if (retcert) {
*retcert = cert;
} else {
if (cert) {
CERT_DestroyCertificate(cert);
}
}
if (retkey) {
*retkey = key;
} else {
if (key) {
SECKEY_DestroyPrivateKey(key);
}
}
return rv;
}
SECStatus NSS_CMSRecipientInfo_Encode(PLArenaPool* poolp,
const NSSCMSRecipientInfo *src,
SECItem* returned)
{
extern const SEC_ASN1Template NSSCMSRecipientInfoTemplate[];
SECStatus rv = SECFailure;
if (!src || !returned) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
} else if (SEC_ASN1EncodeItem(poolp, returned, src,
NSSCMSRecipientInfoTemplate)) {
rv = SECSuccess;
}
return rv;
}