michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: /*
michael@0:  * CMS encryptedData methods.
michael@0:  */
michael@0: 
michael@0: #include "cmslocal.h"
michael@0: 
michael@0: #include "key.h"
michael@0: #include "secasn1.h"
michael@0: #include "secitem.h"
michael@0: #include "secoid.h"
michael@0: #include "pk11func.h"
michael@0: #include "prtime.h"
michael@0: #include "secerr.h"
michael@0: #include "secpkcs5.h"
michael@0: 
michael@0: /*
michael@0:  * NSS_CMSEncryptedData_Create - create an empty encryptedData object.
michael@0:  *
michael@0:  * "algorithm" specifies the bulk encryption algorithm to use.
michael@0:  * "keysize" is the key size.
michael@0:  * 
michael@0:  * An error results in a return value of NULL and an error set.
michael@0:  * (Retrieve specific errors via PORT_GetError()/XP_GetError().)
michael@0:  */
michael@0: NSSCMSEncryptedData *
michael@0: NSS_CMSEncryptedData_Create(NSSCMSMessage *cmsg, SECOidTag algorithm, 
michael@0: 			    int keysize)
michael@0: {
michael@0:     void *mark;
michael@0:     NSSCMSEncryptedData *encd;
michael@0:     PLArenaPool *poolp;
michael@0:     SECAlgorithmID *pbe_algid;
michael@0:     SECStatus rv;
michael@0: 
michael@0:     poolp = cmsg->poolp;
michael@0: 
michael@0:     mark = PORT_ArenaMark(poolp);
michael@0: 
michael@0:     encd = PORT_ArenaZNew(poolp, NSSCMSEncryptedData);
michael@0:     if (encd == NULL)
michael@0: 	goto loser;
michael@0: 
michael@0:     encd->cmsg = cmsg;
michael@0: 
michael@0:     /* version is set in NSS_CMSEncryptedData_Encode_BeforeStart() */
michael@0: 
michael@0:     if (!SEC_PKCS5IsAlgorithmPBEAlgTag(algorithm)) {
michael@0: 	rv = NSS_CMSContentInfo_SetContentEncAlg(poolp, &(encd->contentInfo), 
michael@0: 						 algorithm, NULL, keysize);
michael@0:     } else {
michael@0: 	/* Assume password-based-encryption.  
michael@0: 	 * Note: we can't generate pkcs5v2 from this interface.
michael@0: 	 * PK11_CreateBPEAlgorithmID generates pkcs5v2 by accepting
michael@0: 	 * non-PBE oids and assuming that they are pkcs5v2 oids, but
michael@0: 	 * NSS_CMSEncryptedData_Create accepts non-PBE oids as regular
michael@0: 	 * CMS encrypted data, so we can't tell NSS_CMS_EncryptedData_Create
michael@0: 	 * to create pkcs5v2 PBEs */
michael@0: 	pbe_algid = PK11_CreatePBEAlgorithmID(algorithm, 1, NULL);
michael@0: 	if (pbe_algid == NULL) {
michael@0: 	    rv = SECFailure;
michael@0: 	} else {
michael@0: 	    rv = NSS_CMSContentInfo_SetContentEncAlgID(poolp, 
michael@0: 				&(encd->contentInfo), pbe_algid, keysize);
michael@0: 	    SECOID_DestroyAlgorithmID (pbe_algid, PR_TRUE);
michael@0: 	}
michael@0:     }
michael@0:     if (rv != SECSuccess)
michael@0: 	goto loser;
michael@0: 
michael@0:     PORT_ArenaUnmark(poolp, mark);
michael@0:     return encd;
michael@0: 
michael@0: loser:
michael@0:     PORT_ArenaRelease(poolp, mark);
michael@0:     return NULL;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * NSS_CMSEncryptedData_Destroy - destroy an encryptedData object
michael@0:  */
michael@0: void
michael@0: NSS_CMSEncryptedData_Destroy(NSSCMSEncryptedData *encd)
michael@0: {
michael@0:     /* everything's in a pool, so don't worry about the storage */
michael@0:     NSS_CMSContentInfo_Destroy(&(encd->contentInfo));
michael@0:     return;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * NSS_CMSEncryptedData_GetContentInfo - return pointer to encryptedData object's contentInfo
michael@0:  */
michael@0: NSSCMSContentInfo *
michael@0: NSS_CMSEncryptedData_GetContentInfo(NSSCMSEncryptedData *encd)
michael@0: {
michael@0:     return &(encd->contentInfo);
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * NSS_CMSEncryptedData_Encode_BeforeStart - do all the necessary things to a EncryptedData
michael@0:  *     before encoding begins.
michael@0:  *
michael@0:  * In particular:
michael@0:  *  - set the correct version value.
michael@0:  *  - get the encryption key
michael@0:  */
michael@0: SECStatus
michael@0: NSS_CMSEncryptedData_Encode_BeforeStart(NSSCMSEncryptedData *encd)
michael@0: {
michael@0:     int version;
michael@0:     PK11SymKey *bulkkey = NULL;
michael@0:     SECItem *dummy;
michael@0:     NSSCMSContentInfo *cinfo = &(encd->contentInfo);
michael@0: 
michael@0:     if (NSS_CMSArray_IsEmpty((void **)encd->unprotectedAttr))
michael@0: 	version = NSS_CMS_ENCRYPTED_DATA_VERSION;
michael@0:     else
michael@0: 	version = NSS_CMS_ENCRYPTED_DATA_VERSION_UPATTR;
michael@0:     
michael@0:     dummy = SEC_ASN1EncodeInteger (encd->cmsg->poolp, &(encd->version), version);
michael@0:     if (dummy == NULL)
michael@0: 	return SECFailure;
michael@0: 
michael@0:     /* now get content encryption key (bulk key) by using our cmsg callback */
michael@0:     if (encd->cmsg->decrypt_key_cb)
michael@0: 	bulkkey = (*encd->cmsg->decrypt_key_cb)(encd->cmsg->decrypt_key_cb_arg, 
michael@0: 		    NSS_CMSContentInfo_GetContentEncAlg(cinfo));
michael@0:     if (bulkkey == NULL)
michael@0: 	return SECFailure;
michael@0: 
michael@0:     /* store the bulk key in the contentInfo so that the encoder can find it */
michael@0:     NSS_CMSContentInfo_SetBulkKey(cinfo, bulkkey);
michael@0:     PK11_FreeSymKey (bulkkey);
michael@0: 
michael@0:     return SECSuccess;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * NSS_CMSEncryptedData_Encode_BeforeData - set up encryption
michael@0:  */
michael@0: SECStatus
michael@0: NSS_CMSEncryptedData_Encode_BeforeData(NSSCMSEncryptedData *encd)
michael@0: {
michael@0:     NSSCMSContentInfo *cinfo;
michael@0:     PK11SymKey *bulkkey;
michael@0:     SECAlgorithmID *algid;
michael@0:     SECStatus rv;
michael@0: 
michael@0:     cinfo = &(encd->contentInfo);
michael@0: 
michael@0:     /* find bulkkey and algorithm - must have been set by NSS_CMSEncryptedData_Encode_BeforeStart */
michael@0:     bulkkey = NSS_CMSContentInfo_GetBulkKey(cinfo);
michael@0:     if (bulkkey == NULL)
michael@0: 	return SECFailure;
michael@0:     algid = NSS_CMSContentInfo_GetContentEncAlg(cinfo);
michael@0:     if (algid == NULL)
michael@0: 	return SECFailure;
michael@0: 
michael@0:     rv = NSS_CMSContentInfo_Private_Init(cinfo);
michael@0:     if (rv != SECSuccess) {
michael@0: 	return SECFailure;
michael@0:     }
michael@0:     /* this may modify algid (with IVs generated in a token).
michael@0:      * it is therefore essential that algid is a pointer to the "real" contentEncAlg,
michael@0:      * not just to a copy */
michael@0:     cinfo->privateInfo->ciphcx = NSS_CMSCipherContext_StartEncrypt(encd->cmsg->poolp, bulkkey, algid);
michael@0:     PK11_FreeSymKey(bulkkey);
michael@0:     if (cinfo->privateInfo->ciphcx == NULL)
michael@0: 	return SECFailure;
michael@0: 
michael@0:     return SECSuccess;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * NSS_CMSEncryptedData_Encode_AfterData - finalize this encryptedData for encoding
michael@0:  */
michael@0: SECStatus
michael@0: NSS_CMSEncryptedData_Encode_AfterData(NSSCMSEncryptedData *encd)
michael@0: {
michael@0:     if (encd->contentInfo.privateInfo && encd->contentInfo.privateInfo->ciphcx) {
michael@0: 	NSS_CMSCipherContext_Destroy(encd->contentInfo.privateInfo->ciphcx);
michael@0: 	encd->contentInfo.privateInfo->ciphcx = NULL;
michael@0:     }
michael@0: 
michael@0:     /* nothing to do after data */
michael@0:     return SECSuccess;
michael@0: }
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * NSS_CMSEncryptedData_Decode_BeforeData - find bulk key & set up decryption
michael@0:  */
michael@0: SECStatus
michael@0: NSS_CMSEncryptedData_Decode_BeforeData(NSSCMSEncryptedData *encd)
michael@0: {
michael@0:     PK11SymKey *bulkkey = NULL;
michael@0:     NSSCMSContentInfo *cinfo;
michael@0:     SECAlgorithmID *bulkalg;
michael@0:     SECStatus rv = SECFailure;
michael@0: 
michael@0:     cinfo = &(encd->contentInfo);
michael@0: 
michael@0:     bulkalg = NSS_CMSContentInfo_GetContentEncAlg(cinfo);
michael@0: 
michael@0:     if (encd->cmsg->decrypt_key_cb == NULL)	/* no callback? no key../ */
michael@0: 	goto loser;
michael@0: 
michael@0:     bulkkey = (*encd->cmsg->decrypt_key_cb)(encd->cmsg->decrypt_key_cb_arg, bulkalg);
michael@0:     if (bulkkey == NULL)
michael@0: 	/* no success finding a bulk key */
michael@0: 	goto loser;
michael@0: 
michael@0:     NSS_CMSContentInfo_SetBulkKey(cinfo, bulkkey);
michael@0: 
michael@0:     rv = NSS_CMSContentInfo_Private_Init(cinfo);
michael@0:     if (rv != SECSuccess) {
michael@0: 	goto loser;
michael@0:     }
michael@0:     rv = SECFailure;
michael@0: 
michael@0:     cinfo->privateInfo->ciphcx = NSS_CMSCipherContext_StartDecrypt(bulkkey, bulkalg);
michael@0:     if (cinfo->privateInfo->ciphcx == NULL)
michael@0: 	goto loser;		/* error has been set by NSS_CMSCipherContext_StartDecrypt */
michael@0: 
michael@0: 
michael@0:     /* we are done with (this) bulkkey now. */
michael@0:     PK11_FreeSymKey(bulkkey);
michael@0: 
michael@0:     rv = SECSuccess;
michael@0: 
michael@0: loser:
michael@0:     return rv;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * NSS_CMSEncryptedData_Decode_AfterData - finish decrypting this encryptedData's content
michael@0:  */
michael@0: SECStatus
michael@0: NSS_CMSEncryptedData_Decode_AfterData(NSSCMSEncryptedData *encd)
michael@0: {
michael@0:     if (encd->contentInfo.privateInfo && encd->contentInfo.privateInfo->ciphcx) {
michael@0: 	NSS_CMSCipherContext_Destroy(encd->contentInfo.privateInfo->ciphcx);
michael@0: 	encd->contentInfo.privateInfo->ciphcx = NULL;
michael@0:     }
michael@0: 
michael@0:     return SECSuccess;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * NSS_CMSEncryptedData_Decode_AfterEnd - finish decoding this encryptedData
michael@0:  */
michael@0: SECStatus
michael@0: NSS_CMSEncryptedData_Decode_AfterEnd(NSSCMSEncryptedData *encd)
michael@0: {
michael@0:     /* apply final touches */
michael@0:     return SECSuccess;
michael@0: }