pjs/security/nss/lib/smime/cmsencode.c

741 строка
24 KiB
C

/*
* The contents of this file are subject to the Mozilla Public
* License Version 1.1 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS
* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
* implied. See the License for the specific language governing
* rights and limitations under the License.
*
* The Original Code is the Netscape security libraries.
*
* The Initial Developer of the Original Code is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1994-2000 Netscape Communications Corporation. All
* Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the
* terms of the GNU General Public License Version 2 or later (the
* "GPL"), in which case the provisions of the GPL are applicable
* instead of those above. If you wish to allow use of your
* version of this file only under the terms of the GPL and not to
* allow others to use your version of this file under the MPL,
* indicate your decision by deleting the provisions above and
* replace them with the notice and other provisions required by
* the GPL. If you do not delete the provisions above, a recipient
* may use your version of this file under either the MPL or the
* GPL.
*/
/*
* CMS encoding.
*
* $Id: cmsencode.c,v 1.2 2000-06-13 21:56:29 chrisk%netscape.com Exp $
*/
#include "cmslocal.h"
#include "cert.h"
#include "key.h"
#include "secasn1.h"
#include "secoid.h"
#include "secrng.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;
fprintf(stderr, "kind = %d, depth = %d, len = %d\n", data_kind, 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.
*/
switch (p7ecx->type) {
default:
case SEC_OID_UNKNOWN:
/* 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;
}
break;
case SEC_OID_PKCS7_DATA:
if (before && dest == &(rootcinfo->rawContent)) {
/* just set up encoder to grab from user - no encryption or digesting */
if ((item = rootcinfo->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 */
}
break;
case SEC_OID_PKCS7_SIGNED_DATA:
case SEC_OID_PKCS7_ENVELOPED_DATA:
case SEC_OID_PKCS7_DIGESTED_DATA:
case SEC_OID_PKCS7_ENCRYPTED_DATA:
/* 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 (childtype == SEC_OID_PKCS7_DATA && (item = cinfo->content.data) != NULL)
/* we have data - feed it in */
(void)nss_cms_encoder_work_data(p7ecx, NULL, item->data, item->len, PR_TRUE, PR_TRUE);
else
/* else try to get it from user */
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 */
}
break;
}
}
/*
* 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:
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);
switch (childtype) {
case SEC_OID_PKCS7_SIGNED_DATA:
case SEC_OID_PKCS7_ENVELOPED_DATA:
case SEC_OID_PKCS7_ENCRYPTED_DATA:
case SEC_OID_PKCS7_DIGESTED_DATA:
#if 0
case SEC_OID_PKCS7_DATA: /* XXX here also??? maybe yes! */
#endif
/* 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;
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;
case SEC_OID_PKCS7_DATA:
rv = SECSuccess;
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;
childp7ecx->ecxupdated = PR_FALSE;
/*
* Indicate that we are streaming. We will be streaming until we
* get past the contents bytes.
*/
SEC_ASN1EncoderSetStreaming(childp7ecx->ecx);
/*
* The notify function will watch for the contents field.
*/
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) */
/* 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
* another child encoder). */
if (SEC_ASN1EncoderUpdate(childp7ecx->ecx, NULL, 0) != SECSuccess)
goto loser;
p7ecx->childp7ecx = childp7ecx;
break;
case SEC_OID_PKCS7_DATA:
p7ecx->childp7ecx = NULL;
break;
default:
/* we do not know this type */
p7ecx->error = SEC_ERROR_BAD_DER;
break;
}
return SECSuccess;
loser:
if (childp7ecx) {
if (childp7ecx->ecx)
SEC_ASN1EncoderFinish(childp7ecx->ecx);
PORT_Free(childp7ecx);
}
return SECFailure;
}
static SECStatus
nss_cms_after_data(NSSCMSEncoderContext *p7ecx)
{
SECStatus rv;
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;
case SEC_OID_PKCS7_DATA:
/* do nothing */
break;
default:
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);
/* Update the running digest. */
if (len && cinfo->digcx != NULL)
NSS_CMSDigestContext_Update(cinfo->digcx, data, len);
/* Encrypt this chunk. */
if (cinfo->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->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->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->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 != NULL))
rv = SEC_ASN1EncoderUpdate(p7ecx->ecx, (const char *)data, len);
done:
if (cinfo->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;
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);
switch (NSS_CMSContentInfo_GetContentTypeTag(cinfo)) {
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 = SECFailure;
break;
}
if (rv != SECSuccess)
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.
*/
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). */
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) {
/* 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);
childtype = NSS_CMSContentInfo_GetContentTypeTag(cinfo);
if (childtype != SEC_OID_PKCS7_DATA)
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;
SECOidTag childtype;
/*
* 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_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;
/* find out about our inner content type - must be data */
cinfo = NSS_CMSContent_GetContentInfo(p7ecx->content.pointer, p7ecx->type);
childtype = NSS_CMSContentInfo_GetContentTypeTag(cinfo);
if (childtype == SEC_OID_PKCS7_DATA && cinfo->content.data == NULL) {
SEC_ASN1EncoderClearTakeFromBuf(p7ecx->ecx);
/* now that TakeFromBuf is off, this will kick this encoder to finish encoding */
rv = SEC_ASN1EncoderUpdate(p7ecx->ecx, NULL, 0);
}
SEC_ASN1EncoderClearStreaming(p7ecx->ecx);
if (p7ecx->error)
rv = SECFailure;
loser:
SEC_ASN1EncoderFinish(p7ecx->ecx);
PORT_Free (p7ecx);
return rv;
}