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 /* 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 encoding.

  */

 #include "cmslocal.h"

 #include "cert.h"

 #include "key.h"

 #include "secasn1.h"

 #include "secoid.h"

 #include "secitem.h"

 #include "pk11func.h"

 #include "secerr.h"

 struct nss_cms_encoder_output {

     NSSCMSContentCallback outputfn;

     void *outputarg;

     PLArenaPool *destpoolp;

     SECItem *dest;

 };

 struct NSSCMSEncoderContextStr {

     SEC_ASN1EncoderContext *	ecx;		/* ASN.1 encoder context */

     PRBool			ecxupdated;	/* true if data was handed in */

     NSSCMSMessage *		cmsg;		/* pointer to the root message */

     SECOidTag			type;		/* type tag of the current content */

     NSSCMSContent		content;	/* pointer to current content */

     struct nss_cms_encoder_output output;	/* output function */

     int				error;		/* error code */

     NSSCMSEncoderContext *	childp7ecx;	/* link to child encoder context */

 };

 static SECStatus nss_cms_before_data(NSSCMSEncoderContext *p7ecx);

 static SECStatus nss_cms_after_data(NSSCMSEncoderContext *p7ecx);

 static SECStatus nss_cms_encoder_update(NSSCMSEncoderContext *p7ecx, const char *data, unsigned long len);

 static SECStatus nss_cms_encoder_work_data(NSSCMSEncoderContext *p7ecx, SECItem *dest,

 			     const unsigned char *data, unsigned long len,

 			     PRBool final, PRBool innermost);

 extern const SEC_ASN1Template NSSCMSMessageTemplate[];

 /*

  * The little output function that the ASN.1 encoder calls to hand

  * us bytes which we in turn hand back to our caller (via the callback

  * they gave us).

  */

 static void

 nss_cms_encoder_out(void *arg, const char *buf, unsigned long len,

 		      int depth, SEC_ASN1EncodingPart data_kind)

 {

     struct nss_cms_encoder_output *output = (struct nss_cms_encoder_output *)arg;

     unsigned char *dest;

     unsigned long offset;

 #ifdef CMSDEBUG

     int i;

     const char *data_name = "unknown";

     switch (data_kind) {

     case SEC_ASN1_Identifier:

         data_name = "identifier";

         break;

     case SEC_ASN1_Length:

         data_name = "length";

         break;

     case SEC_ASN1_Contents:

         data_name = "contents";

         break;

     case SEC_ASN1_EndOfContents:

         data_name = "end-of-contents";

         break;

     }

     fprintf(stderr, "kind = %s, depth = %d, len = %d\n", data_name, depth, len);

     for (i=0; i < len; i++) {

 	fprintf(stderr, " %02x%s", (unsigned int)buf[i] & 0xff, ((i % 16) == 15) ? "\n" : "");

     }

     if ((i % 16) != 0)

 	fprintf(stderr, "\n");

 #endif

     if (output->outputfn != NULL)

 	/* call output callback with DER data */

 	output->outputfn(output->outputarg, buf, len);

     if (output->dest != NULL) {

 	/* store DER data in SECItem */

 	offset = output->dest->len;

 	if (offset == 0) {

 	    dest = (unsigned char *)PORT_ArenaAlloc(output->destpoolp, len);

 	} else {

 	    dest = (unsigned char *)PORT_ArenaGrow(output->destpoolp, 

 				  output->dest->data,

 				  output->dest->len,

 				  output->dest->len + len);

 	}

 	if (dest == NULL)

 	    /* oops */

 	    return;

 	output->dest->data = dest;

 	output->dest->len += len;

 	/* copy it in */

 	PORT_Memcpy(output->dest->data + offset, buf, len);

     }

 }

 /*

  * nss_cms_encoder_notify - ASN.1 encoder callback

  *

  * this function is called by the ASN.1 encoder before and after the encoding of

  * every object. here, it is used to keep track of data structures, set up

  * encryption and/or digesting and possibly set up child encoders.

  */

 static void

 nss_cms_encoder_notify(void *arg, PRBool before, void *dest, int depth)

 {

     NSSCMSEncoderContext *p7ecx;

     NSSCMSContentInfo *rootcinfo, *cinfo;

     PRBool after = !before;

     PLArenaPool *poolp;

     SECOidTag childtype;

     SECItem *item;

     p7ecx = (NSSCMSEncoderContext *)arg;

     PORT_Assert(p7ecx != NULL);

     rootcinfo = &(p7ecx->cmsg->contentInfo);

     poolp = p7ecx->cmsg->poolp;

 #ifdef CMSDEBUG

     fprintf(stderr, "%6.6s, dest = 0x%08x, depth = %d\n", before ? "before" : "after", dest, depth);

 #endif

     /*

      * Watch for the content field, at which point we want to instruct

      * the ASN.1 encoder to start taking bytes from the buffer.

      */

     if (NSS_CMSType_IsData(p7ecx->type)) {

 	cinfo = NSS_CMSContent_GetContentInfo(p7ecx->content.pointer, p7ecx->type);

 	if (before && dest == &(cinfo->rawContent)) {

 	    /* just set up encoder to grab from user - no encryption or digesting */

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

 		(void)nss_cms_encoder_work_data(p7ecx, NULL, item->data, item->len, PR_TRUE, PR_TRUE);

 	    else

 		SEC_ASN1EncoderSetTakeFromBuf(p7ecx->ecx);

 	    SEC_ASN1EncoderClearNotifyProc(p7ecx->ecx);	/* no need to get notified anymore */

 	}

     } else if (NSS_CMSType_IsWrapper(p7ecx->type)) {

 	/* when we know what the content is, we encode happily until we reach the inner content */

 	cinfo = NSS_CMSContent_GetContentInfo(p7ecx->content.pointer, p7ecx->type);

 	childtype = NSS_CMSContentInfo_GetContentTypeTag(cinfo);

 	if (after && dest == &(cinfo->contentType)) {

 	    /* we're right before encoding the data (if we have some or not) */

 	    /* (for encrypted data, we're right before the contentEncAlg which may change */

 	    /*  in nss_cms_before_data because of IV calculation when setting up encryption) */

 	    if (nss_cms_before_data(p7ecx) != SECSuccess)

 		p7ecx->error = PORT_GetError();

 	}

 	if (before && dest == &(cinfo->rawContent)) {

 	    if (p7ecx->childp7ecx == NULL) {

 		if ((NSS_CMSType_IsData(childtype) && (item = cinfo->content.data) != NULL)) {

 		    /* we are the innermost non-data and we have data - feed it in */

 		    (void)nss_cms_encoder_work_data(p7ecx, NULL, item->data, item->len, PR_TRUE, PR_TRUE);

 	        } else {

 		    /* else we'll have to get data from user */

 		    SEC_ASN1EncoderSetTakeFromBuf(p7ecx->ecx);

 		}

 	    } else {

 	        /* if we have a nested encoder, wait for its data */

 		SEC_ASN1EncoderSetTakeFromBuf(p7ecx->ecx);

 	    }

 	}

 	if (after && dest == &(cinfo->rawContent)) {

 	    if (nss_cms_after_data(p7ecx) != SECSuccess)

 		p7ecx->error = PORT_GetError();

 	    SEC_ASN1EncoderClearNotifyProc(p7ecx->ecx);	/* no need to get notified anymore */

 	}

     } else {

 	/* we're still in the root message */

 	if (after && dest == &(rootcinfo->contentType)) {

 	    /* got the content type OID now - so find out the type tag */

 	    p7ecx->type = NSS_CMSContentInfo_GetContentTypeTag(rootcinfo);

 	    /* set up a pointer to our current content */

 	    p7ecx->content = rootcinfo->content;

 	}

     }

 }

 /*

  * nss_cms_before_data - setup the current encoder to receive data

  */

 static SECStatus

 nss_cms_before_data(NSSCMSEncoderContext *p7ecx)

 {

     SECStatus rv;

     SECOidTag childtype;

     NSSCMSContentInfo *cinfo;

     PLArenaPool *poolp;

     NSSCMSEncoderContext *childp7ecx;

     const SEC_ASN1Template *template;

     poolp = p7ecx->cmsg->poolp;

     /* call _Encode_BeforeData handlers */

     switch (p7ecx->type) {

     case SEC_OID_PKCS7_SIGNED_DATA:

 	/* we're encoding a signedData, so set up the digests */

 	rv = NSS_CMSSignedData_Encode_BeforeData(p7ecx->content.signedData);

 	break;

     case SEC_OID_PKCS7_DIGESTED_DATA:

 	/* we're encoding a digestedData, so set up the digest */

 	rv = NSS_CMSDigestedData_Encode_BeforeData(p7ecx->content.digestedData);

 	break;

     case SEC_OID_PKCS7_ENVELOPED_DATA:

 	rv = NSS_CMSEnvelopedData_Encode_BeforeData(p7ecx->content.envelopedData);

 	break;

     case SEC_OID_PKCS7_ENCRYPTED_DATA:

 	rv = NSS_CMSEncryptedData_Encode_BeforeData(p7ecx->content.encryptedData);

 	break;

     default:

         if (NSS_CMSType_IsWrapper(p7ecx->type)) {

 	    rv = NSS_CMSGenericWrapperData_Encode_BeforeData(p7ecx->type, p7ecx->content.genericData);

 	} else {

 	    rv = SECFailure;

 	}

     }

     if (rv != SECSuccess)

 	return SECFailure;

     /* ok, now we have a pointer to cinfo */

     /* find out what kind of data is encapsulated */

     cinfo = NSS_CMSContent_GetContentInfo(p7ecx->content.pointer, p7ecx->type);

     childtype = NSS_CMSContentInfo_GetContentTypeTag(cinfo);

     if (NSS_CMSType_IsWrapper(childtype)) {

 	/* in these cases, we need to set up a child encoder! */

 	/* create new encoder context */

 	childp7ecx = PORT_ZAlloc(sizeof(NSSCMSEncoderContext));

 	if (childp7ecx == NULL)

 	    return SECFailure;

 	/* the CHILD encoder needs to hand its encoded data to the CURRENT encoder

 	 * (which will encrypt and/or digest it)

 	 * this needs to route back into our update function

 	 * which finds the lowest encoding context & encrypts and computes digests */

 	childp7ecx->type = childtype;

 	childp7ecx->content = cinfo->content;

 	/* use the non-recursive update function here, of course */

 	childp7ecx->output.outputfn = (NSSCMSContentCallback)nss_cms_encoder_update;

 	childp7ecx->output.outputarg = p7ecx;

 	childp7ecx->output.destpoolp = NULL;

 	childp7ecx->output.dest = NULL;

 	childp7ecx->cmsg = p7ecx->cmsg;

 	childp7ecx->ecxupdated = PR_FALSE;

 	childp7ecx->childp7ecx = NULL;

 	template = NSS_CMSUtil_GetTemplateByTypeTag(childtype);

 	if (template == NULL)

 	    goto loser;		/* cannot happen */

 	/* now initialize the data for encoding the first third */

 	switch (childp7ecx->type) {

 	case SEC_OID_PKCS7_SIGNED_DATA:

 	    rv = NSS_CMSSignedData_Encode_BeforeStart(cinfo->content.signedData);

 	    break;

 	case SEC_OID_PKCS7_ENVELOPED_DATA:

 	    rv = NSS_CMSEnvelopedData_Encode_BeforeStart(cinfo->content.envelopedData);

 	    break;

 	case SEC_OID_PKCS7_DIGESTED_DATA:

 	    rv = NSS_CMSDigestedData_Encode_BeforeStart(cinfo->content.digestedData);

 	    break;

 	case SEC_OID_PKCS7_ENCRYPTED_DATA:

 	    rv = NSS_CMSEncryptedData_Encode_BeforeStart(cinfo->content.encryptedData);

 	    break;

 	default:

 	    rv = NSS_CMSGenericWrapperData_Encode_BeforeStart(childp7ecx->type, cinfo->content.genericData);

 	    break;

 	}

 	if (rv != SECSuccess)

 	    goto loser;

 	/*

 	 * Initialize the BER encoder.

 	 */

 	childp7ecx->ecx = SEC_ASN1EncoderStart(cinfo->content.pointer, template,

 					   nss_cms_encoder_out, &(childp7ecx->output));

 	if (childp7ecx->ecx == NULL)

 	    goto loser;

 	/*

 	 * Indicate that we are streaming.  We will be streaming until we

 	 * get past the contents bytes.

 	 */

         if (!cinfo->privateInfo || !cinfo->privateInfo->dontStream)

 	    SEC_ASN1EncoderSetStreaming(childp7ecx->ecx);

 	/*

 	 * The notify function will watch for the contents field.

 	 */

 	p7ecx->childp7ecx = childp7ecx;

 	SEC_ASN1EncoderSetNotifyProc(childp7ecx->ecx, nss_cms_encoder_notify, childp7ecx);

 	/* please note that we are NOT calling SEC_ASN1EncoderUpdate here to kick off the */

 	/* encoding process - we'll do that from the update function instead */

 	/* otherwise we'd be encoding data from a call of the notify function of the */

 	/* parent encoder (which would not work) */

     } else if (NSS_CMSType_IsData(childtype)) {

 	p7ecx->childp7ecx = NULL;

     } else {

 	/* we do not know this type */

 	p7ecx->error = SEC_ERROR_BAD_DER;

     }

     return SECSuccess;

 loser:

     if (childp7ecx) {

 	if (childp7ecx->ecx)

 	    SEC_ASN1EncoderFinish(childp7ecx->ecx);

 	PORT_Free(childp7ecx);

 	p7ecx->childp7ecx = NULL;

     }

     return SECFailure;

 }

 static SECStatus

 nss_cms_after_data(NSSCMSEncoderContext *p7ecx)

 {

     SECStatus rv = SECFailure;

     switch (p7ecx->type) {

     case SEC_OID_PKCS7_SIGNED_DATA:

 	/* this will finish the digests and sign */

 	rv = NSS_CMSSignedData_Encode_AfterData(p7ecx->content.signedData);

 	break;

     case SEC_OID_PKCS7_ENVELOPED_DATA:

 	rv = NSS_CMSEnvelopedData_Encode_AfterData(p7ecx->content.envelopedData);

 	break;

     case SEC_OID_PKCS7_DIGESTED_DATA:

 	rv = NSS_CMSDigestedData_Encode_AfterData(p7ecx->content.digestedData);

 	break;

     case SEC_OID_PKCS7_ENCRYPTED_DATA:

 	rv = NSS_CMSEncryptedData_Encode_AfterData(p7ecx->content.encryptedData);

 	break;

     default:

         if (NSS_CMSType_IsWrapper(p7ecx->type)) {

 	    rv = NSS_CMSGenericWrapperData_Encode_AfterData(p7ecx->type, p7ecx->content.genericData);

 	} else {

 	    rv = SECFailure;

 	}

 	break;

     }

     return rv;

 }

 /*

  * nss_cms_encoder_work_data - process incoming data

  *

  * (from the user or the next encoding layer)

  * Here, we need to digest and/or encrypt, then pass it on

  */

 static SECStatus

 nss_cms_encoder_work_data(NSSCMSEncoderContext *p7ecx, SECItem *dest,

 			     const unsigned char *data, unsigned long len,

 			     PRBool final, PRBool innermost)

 {

     unsigned char *buf = NULL;

     SECStatus rv;

     NSSCMSContentInfo *cinfo;

     rv = SECSuccess;		/* may as well be optimistic */

     /*

      * We should really have data to process, or we should be trying

      * to finish/flush the last block.  (This is an overly paranoid

      * check since all callers are in this file and simple inspection

      * proves they do it right.  But it could find a bug in future

      * modifications/development, that is why it is here.)

      */

     PORT_Assert ((data != NULL && len) || final);

     /* we got data (either from the caller, or from a lower level encoder) */

     cinfo = NSS_CMSContent_GetContentInfo(p7ecx->content.pointer, p7ecx->type);

     if (!cinfo) {

 	/* The original programmer didn't expect this to happen */

 	p7ecx->error = SEC_ERROR_LIBRARY_FAILURE;

 	return SECFailure;

     }

     /* Update the running digest. */

     if (len && cinfo->privateInfo && cinfo->privateInfo->digcx != NULL)

 	NSS_CMSDigestContext_Update(cinfo->privateInfo->digcx, data, len);

     /* Encrypt this chunk. */

     if (cinfo->privateInfo && cinfo->privateInfo->ciphcx != NULL) {

 	unsigned int inlen;	/* length of data being encrypted */

 	unsigned int outlen;	/* length of encrypted data */

 	unsigned int buflen;	/* length available for encrypted data */

 	inlen = len;

 	buflen = NSS_CMSCipherContext_EncryptLength(cinfo->privateInfo->ciphcx, inlen, final);

 	if (buflen == 0) {

 	    /*

 	     * No output is expected, but the input data may be buffered

 	     * so we still have to call Encrypt.

 	     */

 	    rv = NSS_CMSCipherContext_Encrypt(cinfo->privateInfo->ciphcx, NULL, NULL, 0,

 				   data, inlen, final);

 	    if (final) {

 		len = 0;

 		goto done;

 	    }

 	    return rv;

 	}

 	if (dest != NULL)

 	    buf = (unsigned char*)PORT_ArenaAlloc(p7ecx->cmsg->poolp, buflen);

 	else

 	    buf = (unsigned char*)PORT_Alloc(buflen);

 	if (buf == NULL) {

 	    rv = SECFailure;

 	} else {

 	    rv = NSS_CMSCipherContext_Encrypt(cinfo->privateInfo->ciphcx, buf, &outlen, buflen,

 				   data, inlen, final);

 	    data = buf;

 	    len = outlen;

 	}

 	if (rv != SECSuccess)

 	    /* encryption or malloc failed? */

 	    return rv;

     }

     /*

      * at this point (data,len) has everything we'd like to give to the CURRENT encoder

      * (which will encode it, then hand it back to the user or the parent encoder)

      * We don't encode the data if we're innermost and we're told not to include the data

      */

     if (p7ecx->ecx != NULL && len && (!innermost || cinfo->rawContent != cinfo->content.pointer))

 	rv = SEC_ASN1EncoderUpdate(p7ecx->ecx, (const char *)data, len);

 done:

     if (cinfo->privateInfo && cinfo->privateInfo->ciphcx != NULL) {

 	if (dest != NULL) {

 	    dest->data = buf;

 	    dest->len = len;

 	} else if (buf != NULL) {

 	    PORT_Free (buf);

 	}

     }

     return rv;

 }

 /*

  * nss_cms_encoder_update - deliver encoded data to the next higher level

  *

  * no recursion here because we REALLY want to end up at the next higher encoder!

  */

 static SECStatus

 nss_cms_encoder_update(NSSCMSEncoderContext *p7ecx, const char *data, unsigned long len)

 {

     /* XXX Error handling needs help.  Return what?  Do "Finish" on failure? */

     return nss_cms_encoder_work_data (p7ecx, NULL, (const unsigned char *)data, len, PR_FALSE, PR_FALSE);

 }

 /*

  * NSS_CMSEncoder_Start - set up encoding of a CMS message

  *

  * "cmsg" - message to encode

  * "outputfn", "outputarg" - callback function for delivery of DER-encoded output

  *                           will not be called if NULL.

  * "dest" - if non-NULL, pointer to SECItem that will hold the DER-encoded output

  * "destpoolp" - pool to allocate DER-encoded output in

  * "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

  */

 NSSCMSEncoderContext *

 NSS_CMSEncoder_Start(NSSCMSMessage *cmsg,

 			NSSCMSContentCallback outputfn, void *outputarg,

 			SECItem *dest, PLArenaPool *destpoolp,

 			PK11PasswordFunc pwfn, void *pwfn_arg,

 			NSSCMSGetDecryptKeyCallback decrypt_key_cb, void *decrypt_key_cb_arg,

 			SECAlgorithmID **detached_digestalgs, SECItem **detached_digests)

 {

     NSSCMSEncoderContext *p7ecx;

     SECStatus rv;

     NSSCMSContentInfo *cinfo;

     SECOidTag tag;

     NSS_CMSMessage_SetEncodingParams(cmsg, pwfn, pwfn_arg, decrypt_key_cb, decrypt_key_cb_arg,

 					detached_digestalgs, detached_digests);

     p7ecx = (NSSCMSEncoderContext *)PORT_ZAlloc(sizeof(NSSCMSEncoderContext));

     if (p7ecx == NULL) {

 	PORT_SetError(SEC_ERROR_NO_MEMORY);

 	return NULL;

     }

     p7ecx->cmsg = cmsg;

     p7ecx->output.outputfn = outputfn;

     p7ecx->output.outputarg = outputarg;

     p7ecx->output.dest = dest;

     p7ecx->output.destpoolp = destpoolp;

     p7ecx->type = SEC_OID_UNKNOWN;

     cinfo = NSS_CMSMessage_GetContentInfo(cmsg);

     tag = NSS_CMSContentInfo_GetContentTypeTag(cinfo);

     switch (tag) {

     case SEC_OID_PKCS7_SIGNED_DATA:

 	rv = NSS_CMSSignedData_Encode_BeforeStart(cinfo->content.signedData);

 	break;

     case SEC_OID_PKCS7_ENVELOPED_DATA:

 	rv = NSS_CMSEnvelopedData_Encode_BeforeStart(cinfo->content.envelopedData);

 	break;

     case SEC_OID_PKCS7_DIGESTED_DATA:

 	rv = NSS_CMSDigestedData_Encode_BeforeStart(cinfo->content.digestedData);

 	break;

     case SEC_OID_PKCS7_ENCRYPTED_DATA:

 	rv = NSS_CMSEncryptedData_Encode_BeforeStart(cinfo->content.encryptedData);

 	break;

     default:

         if (NSS_CMSType_IsWrapper(tag)) {

 	    rv = NSS_CMSGenericWrapperData_Encode_BeforeStart(tag, 

 						p7ecx->content.genericData);

 	} else {

 	    rv = SECFailure;

 	}

 	break;

     }

     if (rv != SECSuccess) {

 	PORT_Free(p7ecx);

 	return NULL;

     }

     /* Initialize the BER encoder.

      * Note that this will not encode anything until the first call to SEC_ASN1EncoderUpdate */

     p7ecx->ecx = SEC_ASN1EncoderStart(cmsg, NSSCMSMessageTemplate,

 				       nss_cms_encoder_out, &(p7ecx->output));

     if (p7ecx->ecx == NULL) {

 	PORT_Free (p7ecx);

 	return NULL;

     }

     p7ecx->ecxupdated = PR_FALSE;

     /*

      * Indicate that we are streaming.  We will be streaming until we

      * get past the contents bytes.

      */

     if (!cinfo->privateInfo || !cinfo->privateInfo->dontStream)

 	SEC_ASN1EncoderSetStreaming(p7ecx->ecx);

     /*

      * The notify function will watch for the contents field.

      */

     SEC_ASN1EncoderSetNotifyProc(p7ecx->ecx, nss_cms_encoder_notify, p7ecx);

     /* this will kick off the encoding process & encode everything up to the content bytes,

      * at which point the notify function sets streaming mode (and possibly creates

      * a child encoder). */

     p7ecx->ecxupdated = PR_TRUE;

     if (SEC_ASN1EncoderUpdate(p7ecx->ecx, NULL, 0) != SECSuccess) {

 	PORT_Free (p7ecx);

 	return NULL;

     }

     return p7ecx;

 }

 /*

  * NSS_CMSEncoder_Update - take content data delivery from the user

  *

  * "p7ecx" - encoder context

  * "data" - content data

  * "len" - length of content data

  *

  * need to find the lowest level (and call SEC_ASN1EncoderUpdate on the way down),

  * then hand the data to the work_data fn

  */

 SECStatus

 NSS_CMSEncoder_Update(NSSCMSEncoderContext *p7ecx, const char *data, unsigned long len)

 {

     SECStatus rv;

     NSSCMSContentInfo *cinfo;

     SECOidTag childtype;

     if (p7ecx->error)

 	return SECFailure;

     /* hand data to the innermost decoder */

     if (p7ecx->childp7ecx) {

 	/* tell the child to start encoding, up to its first data byte, if it

 	 * hasn't started yet */

 	if (!p7ecx->childp7ecx->ecxupdated) {

 	    p7ecx->childp7ecx->ecxupdated = PR_TRUE;

 	    if (SEC_ASN1EncoderUpdate(p7ecx->childp7ecx->ecx, NULL, 0) != SECSuccess)

 	        return SECFailure;

 	}

 	/* recursion here */

 	rv = NSS_CMSEncoder_Update(p7ecx->childp7ecx, data, len);

     } else {

 	/* we are at innermost decoder */

 	/* find out about our inner content type - must be data */

 	cinfo = NSS_CMSContent_GetContentInfo(p7ecx->content.pointer, p7ecx->type);

 	if (!cinfo) {

 	    /* The original programmer didn't expect this to happen */

 	    p7ecx->error = SEC_ERROR_LIBRARY_FAILURE;

 	    return SECFailure;

 	}

 	childtype = NSS_CMSContentInfo_GetContentTypeTag(cinfo);

 	if (!NSS_CMSType_IsData(childtype))

 	    return SECFailure;

 	/* and we must not have preset data */

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

 	    return SECFailure;

 	/*  hand it the data so it can encode it (let DER trickle up the chain) */

 	rv = nss_cms_encoder_work_data(p7ecx, NULL, (const unsigned char *)data, len, PR_FALSE, PR_TRUE);

     }

     return rv;

 }

 /*

  * NSS_CMSEncoder_Cancel - stop all encoding

  *

  * we need to walk down the chain of encoders and the finish them from the innermost out

  */

 SECStatus

 NSS_CMSEncoder_Cancel(NSSCMSEncoderContext *p7ecx)

 {

     SECStatus rv = SECFailure;

     /* XXX do this right! */

     /*

      * Finish any inner decoders before us so that all the encoded data is flushed

      * This basically finishes all the decoders from the innermost to the outermost.

      * Finishing an inner decoder may result in data being updated to the outer decoder

      * while we are already in NSS_CMSEncoder_Finish, but that's allright.

      */

     if (p7ecx->childp7ecx) {

 	rv = NSS_CMSEncoder_Cancel(p7ecx->childp7ecx); /* frees p7ecx->childp7ecx */

 	/* remember rv for now */

     }

     /*

      * On the way back up, there will be no more data (if we had an

      * inner encoder, it is done now!)

      * Flush out any remaining data and/or finish digests.

      */

     rv = nss_cms_encoder_work_data(p7ecx, NULL, NULL, 0, PR_TRUE, (p7ecx->childp7ecx == NULL));

     if (rv != SECSuccess)

 	goto loser;

     p7ecx->childp7ecx = NULL;

     /* kick the encoder back into working mode again.

      * We turn off streaming stuff (which will cause the encoder to continue

      * encoding happily, now that we have all the data (like digests) ready for it).

      */

     SEC_ASN1EncoderClearTakeFromBuf(p7ecx->ecx);

     SEC_ASN1EncoderClearStreaming(p7ecx->ecx);

     /* now that TakeFromBuf is off, this will kick this encoder to finish encoding */

     rv = SEC_ASN1EncoderUpdate(p7ecx->ecx, NULL, 0);

 loser:

     SEC_ASN1EncoderFinish(p7ecx->ecx);

     PORT_Free (p7ecx);

     return rv;

 }

 /*

  * NSS_CMSEncoder_Finish - signal the end of data

  *

  * we need to walk down the chain of encoders and the finish them from the innermost out

  */

 SECStatus

 NSS_CMSEncoder_Finish(NSSCMSEncoderContext *p7ecx)

 {

     SECStatus rv = SECFailure;

     NSSCMSContentInfo *cinfo;

     /*

      * Finish any inner decoders before us so that all the encoded data is flushed

      * This basically finishes all the decoders from the innermost to the outermost.

      * Finishing an inner decoder may result in data being updated to the outer decoder

      * while we are already in NSS_CMSEncoder_Finish, but that's allright.

      */

     if (p7ecx->childp7ecx) {

 	/* tell the child to start encoding, up to its first data byte, if it

 	 * hasn't yet */

 	if (!p7ecx->childp7ecx->ecxupdated) {

 	    p7ecx->childp7ecx->ecxupdated = PR_TRUE;

 	    rv = SEC_ASN1EncoderUpdate(p7ecx->childp7ecx->ecx, NULL, 0);

 	    if (rv != SECSuccess) {

 		NSS_CMSEncoder_Finish(p7ecx->childp7ecx); /* frees p7ecx->childp7ecx */

 		goto loser;

 	    }

 	}

 	rv = NSS_CMSEncoder_Finish(p7ecx->childp7ecx); /* frees p7ecx->childp7ecx */

 	if (rv != SECSuccess)

 	    goto loser;

     }

     /*

      * On the way back up, there will be no more data (if we had an

      * inner encoder, it is done now!)

      * Flush out any remaining data and/or finish digests.

      */

     rv = nss_cms_encoder_work_data(p7ecx, NULL, NULL, 0, PR_TRUE, (p7ecx->childp7ecx == NULL));

     if (rv != SECSuccess)

 	goto loser;

     p7ecx->childp7ecx = NULL;

     cinfo = NSS_CMSContent_GetContentInfo(p7ecx->content.pointer, p7ecx->type);

     if (!cinfo) {

 	/* The original programmer didn't expect this to happen */

 	p7ecx->error = SEC_ERROR_LIBRARY_FAILURE;

 	rv = SECFailure;

 	goto loser;

     }

     SEC_ASN1EncoderClearTakeFromBuf(p7ecx->ecx);

     SEC_ASN1EncoderClearStreaming(p7ecx->ecx);

     /* now that TakeFromBuf is off, this will kick this encoder to finish encoding */

     rv = SEC_ASN1EncoderUpdate(p7ecx->ecx, NULL, 0);

     if (p7ecx->error)

 	rv = SECFailure;

 loser:

     SEC_ASN1EncoderFinish(p7ecx->ecx);

     PORT_Free (p7ecx);

     return rv;

 }