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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 attributes.

  */

 #include "cmslocal.h"

 #include "secasn1.h"

 #include "secitem.h"

 #include "secoid.h"

 #include "pk11func.h"

 #include "prtime.h"

 #include "secerr.h"

 /*

  * -------------------------------------------------------------------

  * XXX The following Attribute stuff really belongs elsewhere.

  * The Attribute type is *not* part of CMS but rather X.501.

  * But for now, since CMS is the only customer of attributes,

  * we define them here.  Once there is a use outside of CMS,

  * then change the attribute types and functions from internal

  * to external naming convention, and move them elsewhere!

  */

 /*

  * NSS_CMSAttribute_Create - create an attribute

  *

  * if value is NULL, the attribute won't have a value. It can be added later

  * with NSS_CMSAttribute_AddValue.

  */

 NSSCMSAttribute *

 NSS_CMSAttribute_Create(PLArenaPool *poolp, SECOidTag oidtag, SECItem *value, PRBool encoded)

 {

     NSSCMSAttribute *attr;

     SECItem *copiedvalue;

     void *mark;

     PORT_Assert (poolp != NULL);

     mark = PORT_ArenaMark (poolp);

     attr = (NSSCMSAttribute *)PORT_ArenaZAlloc(poolp, sizeof(NSSCMSAttribute));

     if (attr == NULL)

 	goto loser;

     attr->typeTag = SECOID_FindOIDByTag(oidtag);

     if (attr->typeTag == NULL)

 	goto loser;

     if (SECITEM_CopyItem(poolp, &(attr->type), &(attr->typeTag->oid)) != SECSuccess)

 	goto loser;

     if (value != NULL) {

 	if ((copiedvalue = SECITEM_ArenaDupItem(poolp, value)) == NULL)

 	    goto loser;

 	if (NSS_CMSArray_Add(poolp, (void ***)&(attr->values), (void *)copiedvalue) != SECSuccess)

 	    goto loser;

     }

     attr->encoded = encoded;

     PORT_ArenaUnmark (poolp, mark);

     return attr;

 loser:

     PORT_Assert (mark != NULL);

     PORT_ArenaRelease (poolp, mark);

     return NULL;

 }

 /*

  * NSS_CMSAttribute_AddValue - add another value to an attribute

  */

 SECStatus

 NSS_CMSAttribute_AddValue(PLArenaPool *poolp, NSSCMSAttribute *attr, SECItem *value)

 {

     SECItem *copiedvalue;

     void *mark;

     PORT_Assert (poolp != NULL);

     mark = PORT_ArenaMark(poolp);

     if (value == NULL) {

 	PORT_SetError(SEC_ERROR_INVALID_ARGS);

 	goto loser;

     }

     if ((copiedvalue = SECITEM_ArenaDupItem(poolp, value)) == NULL)

 	goto loser;

     if (NSS_CMSArray_Add(poolp, (void ***)&(attr->values), (void *)copiedvalue) != SECSuccess)

 	goto loser;

     PORT_ArenaUnmark(poolp, mark);

     return SECSuccess;

 loser:

     PORT_Assert (mark != NULL);

     PORT_ArenaRelease (poolp, mark);

     return SECFailure;

 }

 /*

  * NSS_CMSAttribute_GetType - return the OID tag

  */

 SECOidTag

 NSS_CMSAttribute_GetType(NSSCMSAttribute *attr)

 {

     SECOidData *typetag;

     typetag = SECOID_FindOID(&(attr->type));

     if (typetag == NULL)

 	return SEC_OID_UNKNOWN;

     return typetag->offset;

 }

 /*

  * NSS_CMSAttribute_GetValue - return the first attribute value

  *

  * We do some sanity checking first:

  * - Multiple values are *not* expected.

  * - Empty values are *not* expected.

  */

 SECItem *

 NSS_CMSAttribute_GetValue(NSSCMSAttribute *attr)

 {

     SECItem *value;

     if (attr == NULL)

 	return NULL;

     value = attr->values[0];

     if (value == NULL || value->data == NULL || value->len == 0)

 	return NULL;

     if (attr->values[1] != NULL)

 	return NULL;

     return value;

 }

 /*

  * NSS_CMSAttribute_CompareValue - compare the attribute's first value against data

  */

 PRBool

 NSS_CMSAttribute_CompareValue(NSSCMSAttribute *attr, SECItem *av)

 {

     SECItem *value;

     if (attr == NULL)

 	return PR_FALSE;

     value = NSS_CMSAttribute_GetValue(attr);

     return (value != NULL && value->len == av->len &&

 	PORT_Memcmp (value->data, av->data, value->len) == 0);

 }

 /*

  * templates and functions for separate ASN.1 encoding of attributes

  *

  * used in NSS_CMSAttributeArray_Reorder

  */

 /*

  * helper function for dynamic template determination of the attribute value

  */

 static const SEC_ASN1Template *

 cms_attr_choose_attr_value_template(void *src_or_dest, PRBool encoding)

 {

     const SEC_ASN1Template *theTemplate;

     NSSCMSAttribute *attribute;

     SECOidData *oiddata;

     PRBool encoded;

     PORT_Assert (src_or_dest != NULL);

     if (src_or_dest == NULL)

 	return NULL;

     attribute = (NSSCMSAttribute *)src_or_dest;

     if (encoding && (!attribute->values || !attribute->values[0] ||

         attribute->encoded)) {

         /* we're encoding, and the attribute has no value or the attribute

          * value is already encoded. */

         return SEC_ASN1_GET(SEC_AnyTemplate);

     }

     /* get attribute's typeTag */

     oiddata = attribute->typeTag;

     if (oiddata == NULL) {

 	oiddata = SECOID_FindOID(&attribute->type);

 	attribute->typeTag = oiddata;

     }

     if (oiddata == NULL) {

 	/* still no OID tag? OID is unknown then. en/decode value as ANY. */

 	encoded = PR_TRUE;

 	theTemplate = SEC_ASN1_GET(SEC_AnyTemplate);

     } else {

 	switch (oiddata->offset) {

 	case SEC_OID_PKCS9_SMIME_CAPABILITIES:

 	case SEC_OID_SMIME_ENCRYPTION_KEY_PREFERENCE:

 	    /* these guys need to stay DER-encoded */

 	default:

 	    /* same goes for OIDs that are not handled here */

 	    encoded = PR_TRUE;

 	    theTemplate = SEC_ASN1_GET(SEC_AnyTemplate);

 	    break;

 	    /* otherwise choose proper template */

 	case SEC_OID_PKCS9_EMAIL_ADDRESS:

 	case SEC_OID_RFC1274_MAIL:

 	case SEC_OID_PKCS9_UNSTRUCTURED_NAME:

 	    encoded = PR_FALSE;

 	    theTemplate = SEC_ASN1_GET(SEC_IA5StringTemplate);

 	    break;

 	case SEC_OID_PKCS9_CONTENT_TYPE:

 	    encoded = PR_FALSE;

 	    theTemplate = SEC_ASN1_GET(SEC_ObjectIDTemplate);

 	    break;

 	case SEC_OID_PKCS9_MESSAGE_DIGEST:

 	    encoded = PR_FALSE;

 	    theTemplate = SEC_ASN1_GET(SEC_OctetStringTemplate);

 	    break;

 	case SEC_OID_PKCS9_SIGNING_TIME:

 	    encoded = PR_FALSE;

 	    theTemplate = SEC_ASN1_GET(CERT_TimeChoiceTemplate);

 	    break;

 	  /* XXX Want other types here, too */

 	}

     }

     if (encoding) {

 	/*

 	 * If we are encoding and we think we have an already-encoded value,

 	 * then the code which initialized this attribute should have set

 	 * the "encoded" property to true (and we would have returned early,

 	 * up above).  No devastating error, but that code should be fixed.

 	 * (It could indicate that the resulting encoded bytes are wrong.)

 	 */

 	PORT_Assert (!encoded);

     } else {

 	/*

 	 * We are decoding; record whether the resulting value is

 	 * still encoded or not.

 	 */

 	attribute->encoded = encoded;

     }

     return theTemplate;

 }

 static const SEC_ASN1TemplateChooserPtr cms_attr_chooser

 	= cms_attr_choose_attr_value_template;

 const SEC_ASN1Template nss_cms_attribute_template[] = {

     { SEC_ASN1_SEQUENCE,

 	  0, NULL, sizeof(NSSCMSAttribute) },

     { SEC_ASN1_OBJECT_ID,

 	  offsetof(NSSCMSAttribute,type) },

     { SEC_ASN1_DYNAMIC | SEC_ASN1_SET_OF,

 	  offsetof(NSSCMSAttribute,values),

 	  &cms_attr_chooser },

     { 0 }

 };

 const SEC_ASN1Template nss_cms_set_of_attribute_template[] = {

     { SEC_ASN1_SET_OF, 0, nss_cms_attribute_template },

 };

 /* =============================================================================

  * Attribute Array methods

  */

 /*

  * NSS_CMSAttributeArray_Encode - encode an Attribute array as SET OF Attributes

  *

  * If you are wondering why this routine does not reorder the attributes

  * first, and might be tempted to make it do so, see the comment by the

  * call to ReorderAttributes in cmsencode.c.  (Or, see who else calls this

  * and think long and hard about the implications of making it always

  * do the reordering.)

  */

 SECItem *

 NSS_CMSAttributeArray_Encode(PLArenaPool *poolp, NSSCMSAttribute ***attrs, SECItem *dest)

 {

     return SEC_ASN1EncodeItem (poolp, dest, (void *)attrs, nss_cms_set_of_attribute_template);

 }

 /*

  * NSS_CMSAttributeArray_Reorder - sort attribute array by attribute's DER encoding

  *

  * make sure that the order of the attributes guarantees valid DER (which must be

  * in lexigraphically ascending order for a SET OF); if reordering is necessary it

  * will be done in place (in attrs).

  */

 SECStatus

 NSS_CMSAttributeArray_Reorder(NSSCMSAttribute **attrs)

 {

     return NSS_CMSArray_SortByDER((void **)attrs, nss_cms_attribute_template, NULL);

 }

 /*

  * NSS_CMSAttributeArray_FindAttrByOidTag - look through a set of attributes and

  * find one that matches the specified object ID.

  *

  * If "only" is true, then make sure that there is not more than one attribute

  * of the same type.  Otherwise, just return the first one found. (XXX Does

  * anybody really want that first-found behavior?  It was like that when I found it...)

  */

 NSSCMSAttribute *

 NSS_CMSAttributeArray_FindAttrByOidTag(NSSCMSAttribute **attrs, SECOidTag oidtag, PRBool only)

 {

     SECOidData *oid;

     NSSCMSAttribute *attr1, *attr2;

     if (attrs == NULL)

 	return NULL;

     oid = SECOID_FindOIDByTag(oidtag);

     if (oid == NULL)

 	return NULL;

     while ((attr1 = *attrs++) != NULL) {

 	if (attr1->type.len == oid->oid.len && PORT_Memcmp (attr1->type.data,

 							    oid->oid.data,

 							    oid->oid.len) == 0)

 	    break;

     }

     if (attr1 == NULL)

 	return NULL;

     if (!only)

 	return attr1;

     while ((attr2 = *attrs++) != NULL) {

 	if (attr2->type.len == oid->oid.len && PORT_Memcmp (attr2->type.data,

 							    oid->oid.data,

 							    oid->oid.len) == 0)

 	    break;

     }

     if (attr2 != NULL)

 	return NULL;

     return attr1;

 }

 /*

  * NSS_CMSAttributeArray_AddAttr - add an attribute to an

  * array of attributes. 

  */

 SECStatus

 NSS_CMSAttributeArray_AddAttr(PLArenaPool *poolp, NSSCMSAttribute ***attrs, NSSCMSAttribute *attr)

 {

     NSSCMSAttribute *oattr;

     void *mark;

     SECOidTag type;

     mark = PORT_ArenaMark(poolp);

     /* find oidtag of attr */

     type = NSS_CMSAttribute_GetType(attr);

     /* see if we have one already */

     oattr = NSS_CMSAttributeArray_FindAttrByOidTag(*attrs, type, PR_FALSE);

     PORT_Assert (oattr == NULL);

     if (oattr != NULL)

 	goto loser;	/* XXX or would it be better to replace it? */

     /* no, shove it in */

     if (NSS_CMSArray_Add(poolp, (void ***)attrs, (void *)attr) != SECSuccess)

 	goto loser;

     PORT_ArenaUnmark(poolp, mark);

     return SECSuccess;

 loser:

     PORT_ArenaRelease(poolp, mark);

     return SECFailure;

 }

 /*

  * NSS_CMSAttributeArray_SetAttr - set an attribute's value in a set of attributes

  */

 SECStatus

 NSS_CMSAttributeArray_SetAttr(PLArenaPool *poolp, NSSCMSAttribute ***attrs, SECOidTag type, SECItem *value, PRBool encoded)

 {

     NSSCMSAttribute *attr;

     void *mark;

     mark = PORT_ArenaMark(poolp);

     /* see if we have one already */

     attr = NSS_CMSAttributeArray_FindAttrByOidTag(*attrs, type, PR_FALSE);

     if (attr == NULL) {

 	/* not found? create one! */

 	attr = NSS_CMSAttribute_Create(poolp, type, value, encoded);

 	if (attr == NULL)

 	    goto loser;

 	/* and add it to the list */

 	if (NSS_CMSArray_Add(poolp, (void ***)attrs, (void *)attr) != SECSuccess)

 	    goto loser;

     } else {

 	/* found, shove it in */

 	/* XXX we need a decent memory model @#$#$!#!!! */

 	attr->values[0] = value;

 	attr->encoded = encoded;

     }

     PORT_ArenaUnmark (poolp, mark);

     return SECSuccess;

 loser:

     PORT_ArenaRelease (poolp, mark);

     return SECFailure;

 }