security/nss/lib/pkcs7/p7encode.c
author gerv%gerv.net
Wed, 25 Apr 2012 14:50:19 +0000
changeset 10313 008b1ff2736b6eb1af210a57c0bb84c2a58e8547
parent 10103 d37af8e58cca021ef1386e618a1c73c75ad9613a
permissions -rw-r--r--
Bug 716563 - update license to MPL 2. r=rrelyea.

/* 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/. */

/*
 * PKCS7 encoding.
 *
 * $Id$
 */

#include "p7local.h"

#include "cert.h"
#include "cryptohi.h"
#include "keyhi.h"
#include "secasn1.h"
#include "secoid.h"
#include "secitem.h"
#include "pk11func.h"
#include "secerr.h"
#include "sechash.h"	/* for HASH_GetHashObject() */

struct sec_pkcs7_encoder_output {
    SEC_PKCS7EncoderOutputCallback outputfn;
    void *outputarg;
};

struct SEC_PKCS7EncoderContextStr {
    SEC_ASN1EncoderContext *ecx;
    SEC_PKCS7ContentInfo *cinfo;
    struct sec_pkcs7_encoder_output output;
    sec_PKCS7CipherObject *encryptobj;
    const SECHashObject *digestobj;
    void *digestcx;
};


/*
 * 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
sec_pkcs7_encoder_out(void *arg, const char *buf, unsigned long len,
		      int depth, SEC_ASN1EncodingPart data_kind)
{
    struct sec_pkcs7_encoder_output *output;

    output = (struct sec_pkcs7_encoder_output*)arg;
    output->outputfn (output->outputarg, buf, len);
}

static sec_PKCS7CipherObject *
sec_pkcs7_encoder_start_encrypt (SEC_PKCS7ContentInfo *cinfo,
						 PK11SymKey *orig_bulkkey)
{
    SECOidTag kind;
    sec_PKCS7CipherObject *encryptobj;
    SEC_PKCS7RecipientInfo **recipientinfos, *ri;
    SEC_PKCS7EncryptedContentInfo *enccinfo;
    SECKEYPublicKey *publickey = NULL;
    SECKEYPrivateKey *ourPrivKey = NULL;
    PK11SymKey  *bulkkey;
    void *mark, *wincx;
    int i;
    PRArenaPool *arena = NULL;

    /* Get the context in case we need it below. */
    wincx = cinfo->pwfn_arg;

    kind = SEC_PKCS7ContentType (cinfo);
    switch (kind) {
      default:
      case SEC_OID_PKCS7_DATA:
      case SEC_OID_PKCS7_DIGESTED_DATA:
      case SEC_OID_PKCS7_SIGNED_DATA:
	recipientinfos = NULL;
	enccinfo = NULL;
	break;
      case SEC_OID_PKCS7_ENCRYPTED_DATA:
	{
	    SEC_PKCS7EncryptedData *encdp;

	    /* To do EncryptedData we *must* be given a bulk key. */
	    PORT_Assert (orig_bulkkey != NULL);
	    if (orig_bulkkey == NULL) {
		/* XXX error? */
		return NULL;
	    }

	    encdp = cinfo->content.encryptedData;
	    recipientinfos = NULL;
	    enccinfo = &(encdp->encContentInfo);
	}
	break;
      case SEC_OID_PKCS7_ENVELOPED_DATA:
	{
	    SEC_PKCS7EnvelopedData *envdp;

	    envdp = cinfo->content.envelopedData;
	    recipientinfos = envdp->recipientInfos;
	    enccinfo = &(envdp->encContentInfo);
	}
	break;
      case SEC_OID_PKCS7_SIGNED_ENVELOPED_DATA:
	{
	    SEC_PKCS7SignedAndEnvelopedData *saedp;

	    saedp = cinfo->content.signedAndEnvelopedData;
	    recipientinfos = saedp->recipientInfos;
	    enccinfo = &(saedp->encContentInfo);
	}
	break;
    }

    if (enccinfo == NULL)
	return NULL;

    bulkkey = orig_bulkkey;
    if (bulkkey == NULL) {
	CK_MECHANISM_TYPE type = PK11_AlgtagToMechanism(enccinfo->encalg);
	PK11SlotInfo *slot;


	slot = PK11_GetBestSlot(type,cinfo->pwfn_arg);
	if (slot == NULL) {
	    return NULL;
	}
	bulkkey = PK11_KeyGen(slot,type,NULL, enccinfo->keysize/8,
			      cinfo->pwfn_arg);
	PK11_FreeSlot(slot);
	if (bulkkey == NULL) {
	    return NULL;
	}
    }

    encryptobj = NULL;
    mark = PORT_ArenaMark (cinfo->poolp);

    /*
     * Encrypt the bulk key with the public key of each recipient.
     */
    for (i = 0; recipientinfos && (ri = recipientinfos[i]) != NULL; i++) {
	CERTCertificate *cert;
	SECOidTag certalgtag, encalgtag;
	SECStatus rv;
	int data_len;
	SECItem *params = NULL;

	cert = ri->cert;
	PORT_Assert (cert != NULL);
	if (cert == NULL)
	    continue;

	/*
	 * XXX Want an interface that takes a cert and some data and
	 * fills in an algorithmID and encrypts the data with the public
	 * key from the cert.  Or, give me two interfaces -- one which
	 * gets the algorithm tag from a cert (I should not have to go
	 * down into the subjectPublicKeyInfo myself) and another which
	 * takes a public key and algorithm tag and data and encrypts
	 * the data.  Or something like that.  The point is that all
	 * of the following hardwired RSA stuff should be done elsewhere.
	 */

	certalgtag=SECOID_GetAlgorithmTag(&(cert->subjectPublicKeyInfo.algorithm));

	switch (certalgtag) {
	case SEC_OID_PKCS1_RSA_ENCRYPTION:
	    encalgtag = certalgtag;
	    publickey = CERT_ExtractPublicKey (cert);
	    if (publickey == NULL) goto loser;
		
	    data_len = SECKEY_PublicKeyStrength(publickey);
	    ri->encKey.data = 
	        (unsigned char*)PORT_ArenaAlloc(cinfo->poolp ,data_len);
	    ri->encKey.len = data_len;
	    if (ri->encKey.data == NULL) goto loser;

	    rv = PK11_PubWrapSymKey(PK11_AlgtagToMechanism(certalgtag),publickey,
				bulkkey,&ri->encKey);

	    SECKEY_DestroyPublicKey(publickey);
	    publickey = NULL;
	    if (rv != SECSuccess) goto loser;
	    params = NULL; /* paranoia */
	    break;
	default:
	    PORT_SetError (SEC_ERROR_INVALID_ALGORITHM);
	    goto loser;
	}

	rv = SECOID_SetAlgorithmID(cinfo->poolp, &ri->keyEncAlg, encalgtag, 
			params);
	if (rv != SECSuccess)
	    goto loser;
	if (arena) PORT_FreeArena(arena,PR_FALSE);
	arena = NULL;
    }

    encryptobj = sec_PKCS7CreateEncryptObject (cinfo->poolp, bulkkey,
					       enccinfo->encalg,
					       &(enccinfo->contentEncAlg));
    if (encryptobj != NULL) {
	PORT_ArenaUnmark (cinfo->poolp, mark);
	mark = NULL;		/* good one; do not want to release */
    }
    /* fallthru */

loser:
    if (arena) {
	PORT_FreeArena(arena, PR_FALSE);
    }
    if (publickey) {
        SECKEY_DestroyPublicKey(publickey);
    }
    if (ourPrivKey) {
        SECKEY_DestroyPrivateKey(ourPrivKey);
    }
    if (mark != NULL) {
	PORT_ArenaRelease (cinfo->poolp, mark);
    }
    if (orig_bulkkey == NULL) {
	if (bulkkey) PK11_FreeSymKey(bulkkey);
    }

    return encryptobj;
}


static void
sec_pkcs7_encoder_notify (void *arg, PRBool before, void *dest, int depth)
{
    SEC_PKCS7EncoderContext *p7ecx;
    SEC_PKCS7ContentInfo *cinfo;
    SECOidTag kind;
    PRBool before_content;

    /*
     * We want to notice just before the content field.  After fields are
     * not interesting to us.
     */
    if (!before)
	return;

    p7ecx = (SEC_PKCS7EncoderContext*)arg;
    cinfo = p7ecx->cinfo;

    before_content = PR_FALSE;

    /*
     * Watch for the content field, at which point we want to instruct
     * the ASN.1 encoder to start taking bytes from the buffer.
     *
     * XXX The following assumes the inner content type is data;
     * if/when we want to handle fully nested types, this will have
     * to recurse until reaching the innermost data content.
     */
    kind = SEC_PKCS7ContentType (cinfo);
    switch (kind) {
      default:
      case SEC_OID_PKCS7_DATA:
	if (dest == &(cinfo->content.data))
	    before_content = PR_TRUE;
	break;

      case SEC_OID_PKCS7_DIGESTED_DATA:
	{
	    SEC_PKCS7DigestedData *digd;

	    digd = cinfo->content.digestedData;
	    if (digd == NULL)
		break;

	    if (dest == &(digd->contentInfo.content))
		before_content = PR_TRUE;
	}
	break;

      case SEC_OID_PKCS7_ENCRYPTED_DATA:
	{
	    SEC_PKCS7EncryptedData *encd;

	    encd = cinfo->content.encryptedData;
	    if (encd == NULL)
		break;

	    if (dest == &(encd->encContentInfo.encContent))
		before_content = PR_TRUE;
	}
	break;

      case SEC_OID_PKCS7_ENVELOPED_DATA:
	{
	    SEC_PKCS7EnvelopedData *envd;

	    envd = cinfo->content.envelopedData;
	    if (envd == NULL)
		break;

	    if (dest == &(envd->encContentInfo.encContent))
		before_content = PR_TRUE;
	}
	break;

      case SEC_OID_PKCS7_SIGNED_DATA:
	{
	    SEC_PKCS7SignedData *sigd;

	    sigd = cinfo->content.signedData;
	    if (sigd == NULL)
		break;

	    if (dest == &(sigd->contentInfo.content))
		before_content = PR_TRUE;
	}
	break;

      case SEC_OID_PKCS7_SIGNED_ENVELOPED_DATA:
	{
	    SEC_PKCS7SignedAndEnvelopedData *saed;

	    saed = cinfo->content.signedAndEnvelopedData;
	    if (saed == NULL)
		break;

	    if (dest == &(saed->encContentInfo.encContent))
		before_content = PR_TRUE;
	}
	break;
    }

    if (before_content) {
	/*
	 * This will cause the next SEC_ASN1EncoderUpdate to take the
	 * contents bytes from the passed-in buffer.
	 */
	SEC_ASN1EncoderSetTakeFromBuf (p7ecx->ecx);
	/*
	 * And that is all we needed this notify function for.
	 */
	SEC_ASN1EncoderClearNotifyProc (p7ecx->ecx);
    }
}


static SEC_PKCS7EncoderContext *
sec_pkcs7_encoder_start_contexts (SEC_PKCS7ContentInfo *cinfo,
				  PK11SymKey *bulkkey)
{
    SEC_PKCS7EncoderContext *p7ecx;
    SECOidTag kind;
    PRBool encrypt;
    SECItem **digests;
    SECAlgorithmID *digestalg, **digestalgs;

    p7ecx = 
      (SEC_PKCS7EncoderContext*)PORT_ZAlloc (sizeof(SEC_PKCS7EncoderContext));
    if (p7ecx == NULL)
	return NULL;

    digests = NULL;
    digestalg = NULL;
    digestalgs = NULL;
    encrypt = PR_FALSE;

    kind = SEC_PKCS7ContentType (cinfo);
    switch (kind) {
      default:
      case SEC_OID_PKCS7_DATA:
	break;
      case SEC_OID_PKCS7_DIGESTED_DATA:
	digestalg = &(cinfo->content.digestedData->digestAlg);
	break;
      case SEC_OID_PKCS7_SIGNED_DATA:
	digests = cinfo->content.signedData->digests;
	digestalgs = cinfo->content.signedData->digestAlgorithms;
	break;
      case SEC_OID_PKCS7_ENCRYPTED_DATA:
      case SEC_OID_PKCS7_ENVELOPED_DATA:
	encrypt = PR_TRUE;
	break;
      case SEC_OID_PKCS7_SIGNED_ENVELOPED_DATA:
	digests = cinfo->content.signedAndEnvelopedData->digests;
	digestalgs = cinfo->content.signedAndEnvelopedData->digestAlgorithms;
	encrypt = PR_TRUE;
	break;
    }

    if (encrypt) {
	p7ecx->encryptobj = sec_pkcs7_encoder_start_encrypt (cinfo, bulkkey);
	if (p7ecx->encryptobj == NULL) {
	    PORT_Free (p7ecx);
	    return NULL;
	}
    }

    if (digestalgs != NULL) {
	if (digests != NULL) {
	    /* digests already created (probably for detached data) */
	    digestalg = NULL;
	} else {
	    /*
	     * XXX Some day we should handle multiple digests; for now,
	     * assume only one will be done.
	     */
	    PORT_Assert (digestalgs[0] != NULL && digestalgs[1] == NULL);
	    digestalg = digestalgs[0];
	}
    }

    if (digestalg != NULL) {
	SECOidTag  oidTag = SECOID_FindOIDTag(&(digestalg->algorithm));

	p7ecx->digestobj = HASH_GetHashObjectByOidTag(oidTag);
	if (p7ecx->digestobj != NULL) {
	    p7ecx->digestcx = (* p7ecx->digestobj->create) ();
	    if (p7ecx->digestcx == NULL)
		p7ecx->digestobj = NULL;
	    else
		(* p7ecx->digestobj->begin) (p7ecx->digestcx);
	}
	if (p7ecx->digestobj == NULL) {
	    if (p7ecx->encryptobj != NULL)
		sec_PKCS7DestroyEncryptObject (p7ecx->encryptobj);
	    PORT_Free (p7ecx);
	    return NULL;
	}
    }

    p7ecx->cinfo = cinfo;
    return p7ecx;
}


SEC_PKCS7EncoderContext *
SEC_PKCS7EncoderStart (SEC_PKCS7ContentInfo *cinfo,
		       SEC_PKCS7EncoderOutputCallback outputfn,
		       void *outputarg,
		       PK11SymKey *bulkkey)
{
    SEC_PKCS7EncoderContext *p7ecx;
    SECStatus rv;

    p7ecx = sec_pkcs7_encoder_start_contexts (cinfo, bulkkey);
    if (p7ecx == NULL)
	return NULL;

    p7ecx->output.outputfn = outputfn;
    p7ecx->output.outputarg = outputarg;

    /*
     * Initialize the BER encoder.
     */
    p7ecx->ecx = SEC_ASN1EncoderStart (cinfo, sec_PKCS7ContentInfoTemplate,
				       sec_pkcs7_encoder_out, &(p7ecx->output));
    if (p7ecx->ecx == NULL) {
	PORT_Free (p7ecx);
	return NULL;
    }

    /*
     * 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, sec_pkcs7_encoder_notify, p7ecx);

    /*
     * This will encode everything up to the content bytes.  (The notify
     * function will then cause the encoding to stop there.)  Then our
     * caller can start passing contents bytes to our Update, which we
     * will pass along.
     */
    rv = SEC_ASN1EncoderUpdate (p7ecx->ecx, NULL, 0);
    if (rv != SECSuccess) {
	PORT_Free (p7ecx);
	return NULL;
    }

    return p7ecx;
}


/*
 * XXX If/when we support nested contents, this needs to be revised.
 */
static SECStatus
sec_pkcs7_encoder_work_data (SEC_PKCS7EncoderContext *p7ecx, SECItem *dest,
			     const unsigned char *data, unsigned long len,
			     PRBool final)
{
    unsigned char *buf = NULL;
    SECStatus rv;


    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);

    /*
     * Update the running digest.
     * XXX This needs modification if/when we handle multiple digests.
     */
    if (len && p7ecx->digestobj != NULL) {
	(* p7ecx->digestobj->update) (p7ecx->digestcx, data, len);
    }

    /*
     * Encrypt this chunk.
     */
    if (p7ecx->encryptobj != NULL) {
	/* XXX the following lengths should all be longs? */
	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 = sec_PKCS7EncryptLength (p7ecx->encryptobj, inlen, final);
	if (buflen == 0) {
	    /*
	     * No output is expected, but the input data may be buffered
	     * so we still have to call Encrypt.
	     */
	    rv = sec_PKCS7Encrypt (p7ecx->encryptobj, NULL, NULL, 0,
				   data, inlen, final);
	    if (final) {
		len = 0;
		goto done;
	    }
	    return rv;
	}

	if (dest != NULL)
	    buf = (unsigned char*)PORT_ArenaAlloc(p7ecx->cinfo->poolp, buflen);
	else
	    buf = (unsigned char*)PORT_Alloc (buflen);

	if (buf == NULL) {
	    rv = SECFailure;
	} else {
	    rv = sec_PKCS7Encrypt (p7ecx->encryptobj, buf, &outlen, buflen,
				   data, inlen, final);
	    data = buf;
	    len = outlen;
	}
	if (rv != SECSuccess) {
	    if (final)
		goto done;
	    return rv;
	}
    }

    if (p7ecx->ecx != NULL) {
	/*
	 * Encode the contents bytes.
	 */
	if(len) {
	    rv = SEC_ASN1EncoderUpdate (p7ecx->ecx, (const char *)data, len);
	}
    }

done:
    if (p7ecx->encryptobj != NULL) {
	if (final)
	    sec_PKCS7DestroyEncryptObject (p7ecx->encryptobj);
	if (dest != NULL) {
	    dest->data = buf;
	    dest->len = len;
	} else if (buf != NULL) {
	    PORT_Free (buf);
	}
    }

    if (final && p7ecx->digestobj != NULL) {
	SECItem *digest, **digests, ***digestsp;
	unsigned char *digdata;
	SECOidTag kind;

	kind = SEC_PKCS7ContentType (p7ecx->cinfo);
	switch (kind) {
	  default:
	    PORT_Assert (0);
	    return SECFailure;
	  case SEC_OID_PKCS7_DIGESTED_DATA:
	    digest = &(p7ecx->cinfo->content.digestedData->digest);
	    digestsp = NULL;
	    break;
	  case SEC_OID_PKCS7_SIGNED_DATA:
	    digest = NULL;
	    digestsp = &(p7ecx->cinfo->content.signedData->digests);
	    break;
	  case SEC_OID_PKCS7_SIGNED_ENVELOPED_DATA:
	    digest = NULL;
	    digestsp = &(p7ecx->cinfo->content.signedAndEnvelopedData->digests);
	    break;
	}

	digdata = (unsigned char*)PORT_ArenaAlloc (p7ecx->cinfo->poolp,
				   p7ecx->digestobj->length);
	if (digdata == NULL)
	    return SECFailure;

	if (digestsp != NULL) {
	    PORT_Assert (digest == NULL);

	    digest = (SECItem*)PORT_ArenaAlloc (p7ecx->cinfo->poolp, 
						sizeof(SECItem));
	    digests = (SECItem**)PORT_ArenaAlloc (p7ecx->cinfo->poolp,
				       2 * sizeof(SECItem *));
	    if (digests == NULL || digest == NULL)
		return SECFailure;

	    digests[0] = digest;
	    digests[1] = NULL;

	    *digestsp = digests;
	}

	PORT_Assert (digest != NULL);

	digest->data = digdata;
	digest->len = p7ecx->digestobj->length;

	(* p7ecx->digestobj->end) (p7ecx->digestcx, digest->data,
				   &(digest->len), digest->len);
	(* p7ecx->digestobj->destroy) (p7ecx->digestcx, PR_TRUE);
    }

    return rv;
}


SECStatus
SEC_PKCS7EncoderUpdate (SEC_PKCS7EncoderContext *p7ecx,
			const char *data, unsigned long len)
{
    /* XXX Error handling needs help.  Return what?  Do "Finish" on failure? */
    return sec_pkcs7_encoder_work_data (p7ecx, NULL,
					(const unsigned char *)data, len,
					PR_FALSE);
}

static SECStatus
sec_pkcs7_encoder_sig_and_certs (SEC_PKCS7ContentInfo *cinfo,
				 SECKEYGetPasswordKey pwfn, void *pwfnarg)
{
    SECOidTag kind;
    CERTCertificate **certs;
    CERTCertificateList **certlists;
    SECAlgorithmID **digestalgs;
    SECItem **digests;
    SEC_PKCS7SignerInfo *signerinfo, **signerinfos;
    SECItem **rawcerts, ***rawcertsp;
    PRArenaPool *poolp;
    int certcount;
    int ci, cli, rci, si;

    kind = SEC_PKCS7ContentType (cinfo);
    switch (kind) {
      default:
      case SEC_OID_PKCS7_DATA:
      case SEC_OID_PKCS7_DIGESTED_DATA:
      case SEC_OID_PKCS7_ENCRYPTED_DATA:
      case SEC_OID_PKCS7_ENVELOPED_DATA:
	certs = NULL;
	certlists = NULL;
	digestalgs = NULL;
	digests = NULL;
	signerinfos = NULL;
	rawcertsp = NULL;
	break;
      case SEC_OID_PKCS7_SIGNED_DATA:
	{
	    SEC_PKCS7SignedData *sdp;

	    sdp = cinfo->content.signedData;
	    certs = sdp->certs;
	    certlists = sdp->certLists;
	    digestalgs = sdp->digestAlgorithms;
	    digests = sdp->digests;
	    signerinfos = sdp->signerInfos;
	    rawcertsp = &(sdp->rawCerts);
	}
	break;
      case SEC_OID_PKCS7_SIGNED_ENVELOPED_DATA:
	{
	    SEC_PKCS7SignedAndEnvelopedData *saedp;

	    saedp = cinfo->content.signedAndEnvelopedData;
	    certs = saedp->certs;
	    certlists = saedp->certLists;
	    digestalgs = saedp->digestAlgorithms;
	    digests = saedp->digests;
	    signerinfos = saedp->signerInfos;
	    rawcertsp = &(saedp->rawCerts);
	}
	break;
    }

    if (certs == NULL && certlists == NULL && signerinfos == NULL)
	return SECSuccess;		/* nothing for us to do! */

    poolp = cinfo->poolp;
    certcount = 0;

    if (signerinfos != NULL) {
	SECOidTag digestalgtag;
	int di;
	SECStatus rv;
	CERTCertificate *cert;
	SECKEYPrivateKey *privkey;
	SECItem signature;
	SECOidTag signalgtag;

	PORT_Assert (digestalgs != NULL && digests != NULL);

	/*
	 * If one fails, we bail right then.  If we want to continue and
	 * try to do subsequent signatures, this loop, and the departures
	 * from it, will need to be reworked.
	 */
	for (si = 0; signerinfos[si] != NULL; si++) {

	    signerinfo = signerinfos[si];

	    /* find right digest */
	    digestalgtag = SECOID_GetAlgorithmTag (&(signerinfo->digestAlg));
	    for (di = 0; digestalgs[di] != NULL; di++) {
		/* XXX Should I be comparing more than the tag? */
		if (digestalgtag == SECOID_GetAlgorithmTag (digestalgs[di]))
		    break;
	    }
	    if (digestalgs[di] == NULL) {
		/* XXX oops; do what? set an error? */
		return SECFailure;
	    }
	    PORT_Assert (digests[di] != NULL);

	    cert = signerinfo->cert;
	    privkey = PK11_FindKeyByAnyCert (cert, pwfnarg);
	    if (privkey == NULL)
		return SECFailure;

	    /*
	     * XXX I think there should be a cert-level interface for this,
	     * so that I do not have to know about subjectPublicKeyInfo...
	     */
	    signalgtag = SECOID_GetAlgorithmTag (&(cert->subjectPublicKeyInfo.algorithm));

	    if (signerinfo->authAttr != NULL) {
		SEC_PKCS7Attribute *attr;
		SECItem encoded_attrs;
		SECItem *dummy;
		SECOidTag algid;

		/*
		 * First, find and fill in the message digest attribute.
		 */
		attr = sec_PKCS7FindAttribute (signerinfo->authAttr,
					       SEC_OID_PKCS9_MESSAGE_DIGEST,
					       PR_TRUE);
		PORT_Assert (attr != NULL);
		if (attr == NULL) {
		    SECKEY_DestroyPrivateKey (privkey);
		    return SECFailure;
		}

		/*
		 * XXX The second half of the following assertion prevents
		 * the encoder from being called twice on the same content.
		 * Either just remove the second half the assertion, or
		 * change the code to check if the value already there is
		 * the same as digests[di], whichever seems more right.
		 */
		PORT_Assert (attr->values != NULL && attr->values[0] == NULL);
		attr->values[0] = digests[di];

		/*
		 * Before encoding, reorder the attributes so that when they
		 * are encoded, they will be conforming DER, which is required
		 * to have a specific order and that is what must be used for
		 * the hash/signature.  We do this here, rather than building
		 * it into EncodeAttributes, because we do not want to do
		 * such reordering on incoming messages (which also uses
		 * EncodeAttributes) or our old signatures (and other "broken"
		 * implementations) will not verify.  So, we want to guarantee
		 * that we send out good DER encodings of attributes, but not
		 * to expect to receive them.
		 */
		rv = sec_PKCS7ReorderAttributes (signerinfo->authAttr);
		if (rv != SECSuccess) {
		    SECKEY_DestroyPrivateKey (privkey);
		    return SECFailure;
		}

		encoded_attrs.data = NULL;
		encoded_attrs.len = 0;
		dummy = sec_PKCS7EncodeAttributes (NULL, &encoded_attrs,
						   &(signerinfo->authAttr));
		if (dummy == NULL) {
		    SECKEY_DestroyPrivateKey (privkey);
		    return SECFailure;
		}

	        algid = SEC_GetSignatureAlgorithmOidTag(privkey->keyType,
 							digestalgtag);
		if (algid == SEC_OID_UNKNOWN) {
		    PORT_SetError(SEC_ERROR_INVALID_ALGORITHM);
		    SECKEY_DestroyPrivateKey (privkey);
		    return SECFailure;
		}
		rv = SEC_SignData (&signature,
				   encoded_attrs.data, encoded_attrs.len,
				   privkey,
				   algid);
		SECITEM_FreeItem (&encoded_attrs, PR_FALSE);
	    } else {
		rv = SGN_Digest (privkey, digestalgtag, &signature,
				 digests[di]);
	    }

	    SECKEY_DestroyPrivateKey (privkey);

	    if (rv != SECSuccess)
		return rv;

	    rv = SECITEM_CopyItem (poolp, &(signerinfo->encDigest), &signature);
	    if (rv != SECSuccess)
		return rv;

	    SECITEM_FreeItem (&signature, PR_FALSE);

	    rv = SECOID_SetAlgorithmID (poolp, &(signerinfo->digestEncAlg),
					signalgtag, NULL);
	    if (rv != SECSuccess)
		return SECFailure;

	    /*
	     * Count the cert chain for this signer.
	     */
	    if (signerinfo->certList != NULL)
		certcount += signerinfo->certList->len;
	}
    }

    if (certs != NULL) {
	for (ci = 0; certs[ci] != NULL; ci++)
	    certcount++;
    }

    if (certlists != NULL) {
	for (cli = 0; certlists[cli] != NULL; cli++)
	    certcount += certlists[cli]->len;
    }

    if (certcount == 0)
	return SECSuccess;		/* signing done; no certs */

    /*
     * Combine all of the certs and cert chains into rawcerts.
     * Note: certcount is an upper bound; we may not need that many slots
     * but we will allocate anyway to avoid having to do another pass.
     * (The temporary space saving is not worth it.)
     */
    rawcerts = (SECItem**)PORT_ArenaAlloc (poolp, 
					(certcount + 1) * sizeof(SECItem *));
    if (rawcerts == NULL)
	return SECFailure;

    /*
     * XXX Want to check for duplicates and not add *any* cert that is
     * already in the set.  This will be more important when we start
     * dealing with larger sets of certs, dual-key certs (signing and
     * encryption), etc.  For the time being we can slide by...
     */
    rci = 0;
    if (signerinfos != NULL) {
	for (si = 0; signerinfos[si] != NULL; si++) {
	    signerinfo = signerinfos[si];
	    for (ci = 0; ci < signerinfo->certList->len; ci++)
		rawcerts[rci++] = &(signerinfo->certList->certs[ci]);
	}

    }

    if (certs != NULL) {
	for (ci = 0; certs[ci] != NULL; ci++)
	    rawcerts[rci++] = &(certs[ci]->derCert);
    }

    if (certlists != NULL) {
	for (cli = 0; certlists[cli] != NULL; cli++) {
	    for (ci = 0; ci < certlists[cli]->len; ci++)
		rawcerts[rci++] = &(certlists[cli]->certs[ci]);
	}
    }

    rawcerts[rci] = NULL;
    *rawcertsp = rawcerts;

    return SECSuccess;
}


SECStatus
SEC_PKCS7EncoderFinish (SEC_PKCS7EncoderContext *p7ecx,
			SECKEYGetPasswordKey pwfn, void *pwfnarg)
{
    SECStatus rv;

    /*
     * Flush out any remaining data.
     */
    rv = sec_pkcs7_encoder_work_data (p7ecx, NULL, NULL, 0, PR_TRUE);

    /*
     * Turn off streaming stuff.
     */
    SEC_ASN1EncoderClearTakeFromBuf (p7ecx->ecx);
    SEC_ASN1EncoderClearStreaming (p7ecx->ecx);

    if (rv != SECSuccess)
	goto loser;

    rv = sec_pkcs7_encoder_sig_and_certs (p7ecx->cinfo, pwfn, pwfnarg);
    if (rv != SECSuccess)
	goto loser;

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

loser:
    SEC_ASN1EncoderFinish (p7ecx->ecx);
    PORT_Free (p7ecx);
    return rv;
}

/*
 * Abort the ASN.1 stream. Used by pkcs 12
 */
void
SEC_PKCS7EncoderAbort(SEC_PKCS7EncoderContext *p7ecx, int error)
{
    PORT_Assert(p7ecx);
    SEC_ASN1EncoderAbort(p7ecx->ecx, error);
}

/*
 * After this routine is called, the entire PKCS7 contentInfo is ready
 * to be encoded.  This is used internally, but can also be called from
 * elsewhere for those who want to be able to just have pointers to
 * the ASN1 template for pkcs7 contentInfo built into their own encodings.
 */
SECStatus
SEC_PKCS7PrepareForEncode (SEC_PKCS7ContentInfo *cinfo,
			   PK11SymKey *bulkkey,
			   SECKEYGetPasswordKey pwfn,
			   void *pwfnarg)
{
    SEC_PKCS7EncoderContext *p7ecx;
    SECItem *content, *enc_content;
    SECStatus rv;

    p7ecx = sec_pkcs7_encoder_start_contexts (cinfo, bulkkey);
    if (p7ecx == NULL)
	return SECFailure;

    content = SEC_PKCS7GetContent (cinfo);

    if (p7ecx->encryptobj != NULL) {
	SECOidTag kind;
	SEC_PKCS7EncryptedContentInfo *enccinfo;

	kind = SEC_PKCS7ContentType (p7ecx->cinfo);
	switch (kind) {
	  default:
	    PORT_Assert (0);
	    rv = SECFailure;
	    goto loser;
	  case SEC_OID_PKCS7_ENCRYPTED_DATA:
	    enccinfo = &(p7ecx->cinfo->content.encryptedData->encContentInfo);
	    break;
	  case SEC_OID_PKCS7_ENVELOPED_DATA:
	    enccinfo = &(p7ecx->cinfo->content.envelopedData->encContentInfo);
	    break;
	  case SEC_OID_PKCS7_SIGNED_ENVELOPED_DATA:
	    enccinfo = &(p7ecx->cinfo->content.signedAndEnvelopedData->encContentInfo);
	    break;
	}
	enc_content = &(enccinfo->encContent);
    } else {
	enc_content = NULL;
    }

    if (content != NULL && content->data != NULL && content->len) {
	rv = sec_pkcs7_encoder_work_data (p7ecx, enc_content,
					  content->data, content->len, PR_TRUE);
	if (rv != SECSuccess)
	    goto loser;
    }

    rv = sec_pkcs7_encoder_sig_and_certs (cinfo, pwfn, pwfnarg);

loser:
    PORT_Free (p7ecx);
    return rv;
}


/*
 * Encode a PKCS7 object, in one shot.  All necessary components
 * of the object must already be specified.  Either the data has
 * already been included (via SetContent), or the data is detached,
 * or there is no data at all (certs-only).
 *
 * "cinfo" specifies the object to be encoded.
 *
 * "outputfn" is where the encoded bytes will be passed.
 *
 * "outputarg" is an opaque argument to the above callback.
 *
 * "bulkkey" specifies the bulk encryption key to use.   This argument
 * can be NULL if no encryption is being done, or if the bulk key should
 * be generated internally (usually the case for EnvelopedData but never
 * for EncryptedData, which *must* provide a bulk encryption key).
 *
 * "pwfn" is a callback for getting the password which protects the
 * private key of the signer.  This argument can be NULL if it is known
 * that no signing is going to be done.
 *
 * "pwfnarg" is an opaque argument to the above callback.
 */
SECStatus
SEC_PKCS7Encode (SEC_PKCS7ContentInfo *cinfo,
		 SEC_PKCS7EncoderOutputCallback outputfn,
		 void *outputarg,
		 PK11SymKey *bulkkey,
		 SECKEYGetPasswordKey pwfn,
		 void *pwfnarg)
{
    SECStatus rv;

    rv = SEC_PKCS7PrepareForEncode (cinfo, bulkkey, pwfn, pwfnarg);
    if (rv == SECSuccess) {
	struct sec_pkcs7_encoder_output outputcx;

	outputcx.outputfn = outputfn;
	outputcx.outputarg = outputarg;

	rv = SEC_ASN1Encode (cinfo, sec_PKCS7ContentInfoTemplate,
			     sec_pkcs7_encoder_out, &outputcx);
    }

    return rv;
}


/*
 * Encode a PKCS7 object, in one shot.  All necessary components
 * of the object must already be specified.  Either the data has
 * already been included (via SetContent), or the data is detached,
 * or there is no data at all (certs-only).  The output, rather than
 * being passed to an output function as is done above, is all put
 * into a SECItem.
 *
 * "pool" specifies a pool from which to allocate the result.
 * It can be NULL, in which case memory is allocated generically.
 *
 * "dest" specifies a SECItem in which to put the result data.
 * It can be NULL, in which case the entire item is allocated, too.
 *
 * "cinfo" specifies the object to be encoded.
 *
 * "bulkkey" specifies the bulk encryption key to use.   This argument
 * can be NULL if no encryption is being done, or if the bulk key should
 * be generated internally (usually the case for EnvelopedData but never
 * for EncryptedData, which *must* provide a bulk encryption key).
 *
 * "pwfn" is a callback for getting the password which protects the
 * private key of the signer.  This argument can be NULL if it is known
 * that no signing is going to be done.
 *
 * "pwfnarg" is an opaque argument to the above callback.
 */
SECItem *
SEC_PKCS7EncodeItem (PRArenaPool *pool,
		     SECItem *dest,
		     SEC_PKCS7ContentInfo *cinfo,
		     PK11SymKey *bulkkey,
		     SECKEYGetPasswordKey pwfn,
		     void *pwfnarg)
{
    SECStatus rv;

    rv = SEC_PKCS7PrepareForEncode (cinfo, bulkkey, pwfn, pwfnarg);
    if (rv != SECSuccess)
	return NULL;

    return SEC_ASN1EncodeItem (pool, dest, cinfo, sec_PKCS7ContentInfoTemplate);
}