usr/src/lib/libgss/g_imp_name.c - illumos-gate - Gitiles

 /*
  * CDDL HEADER START
  *
  * The contents of this file are subject to the terms of the
  * Common Development and Distribution License (the "License").
  * You may not use this file except in compliance with the License.
  *
  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  * or http://www.opensolaris.org/os/licensing.
  * See the License for the specific language governing permissions
  * and limitations under the License.
  *
  * When distributing Covered Code, include this CDDL HEADER in each
  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  * If applicable, add the following below this CDDL HEADER, with the
  * fields enclosed by brackets "[]" replaced with your own identifying
  * information: Portions Copyright [yyyy] [name of copyright owner]
  *
  * CDDL HEADER END
  */
 /*
  * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
  */

 /*
  *  glue routine gss_import_name
  *
  */

 #include <mechglueP.h>
 #include "gssapiP_generic.h"
 #include <stdio.h>
 #ifdef HAVE_STDLIB_H
 #include <stdlib.h>
 #endif
 #include <string.h>
 #include <errno.h>

 extern int
 get_der_length(unsigned char **, unsigned int, unsigned int *);

 /* local function to import GSS_C_EXPORT_NAME names */
 static OM_uint32 importExportName(OM_uint32 *, gss_union_name_t);

 static OM_uint32
 val_imp_name_args(
 	OM_uint32 *minor_status,
 	gss_buffer_t input_name_buffer,
 	gss_name_t *output_name)
 {

 	/* Initialize outputs. */

 	if (minor_status != NULL)
 		*minor_status = 0;

 	if (output_name != NULL)
 		*output_name = GSS_C_NO_NAME;

 	/* Validate arguments. */

 	if (minor_status == NULL)
 		return (GSS_S_CALL_INACCESSIBLE_WRITE);

 	if (output_name == NULL)
 		return (GSS_S_CALL_INACCESSIBLE_WRITE);

 	if (input_name_buffer == GSS_C_NO_BUFFER)
 		return (GSS_S_CALL_INACCESSIBLE_READ | GSS_S_BAD_NAME);

 	if (GSS_EMPTY_BUFFER(input_name_buffer))
 		return (GSS_S_CALL_INACCESSIBLE_READ | GSS_S_BAD_NAME);

 	return (GSS_S_COMPLETE);
 }

 OM_uint32
 gss_import_name(minor_status,
 		input_name_buffer,
 		input_name_type,
 		output_name)

 OM_uint32 *minor_status;
 const gss_buffer_t input_name_buffer;
 const gss_OID input_name_type;
 gss_name_t *output_name;
 {
 	gss_union_name_t union_name;
 	OM_uint32 major_status = GSS_S_FAILURE, tmp;

 	major_status = val_imp_name_args(minor_status,
 					input_name_buffer,
 					output_name);
 	if (major_status != GSS_S_COMPLETE)
 		return (major_status);

 	/*
 	 * First create the union name struct that will hold the external
 	 * name and the name type.
 	 */
 	union_name = (gss_union_name_t)malloc(sizeof (gss_union_name_desc));
 	if (!union_name)
 		return (GSS_S_FAILURE);

 	union_name->mech_type = 0;
 	union_name->mech_name = 0;
 	union_name->name_type = 0;
 	union_name->external_name = 0;

 	/*
 	 * All we do here is record the external name and name_type.
 	 * When the name is actually used, the underlying gss_import_name()
 	 * is called for the appropriate mechanism.  The exception to this
 	 * rule is when the name of GSS_C_NT_EXPORT_NAME type.  If that is
 	 * the case, then we make it MN in this call.
 	 */
 	major_status = gssint_create_copy_buffer(input_name_buffer,
 					&union_name->external_name, 0);
 	if (major_status != GSS_S_COMPLETE) {
 		free(union_name);
 		return (major_status);
 	}

 	if (input_name_type != GSS_C_NULL_OID) {
 		major_status = generic_gss_copy_oid(minor_status,
 						input_name_type,
 						&union_name->name_type);
 		if (major_status != GSS_S_COMPLETE) {
 			map_errcode(minor_status);
 			goto allocation_failure;
 		}
 	}

 	/*
 	 * In MIT Distribution the mechanism is determined from the nametype;
 	 * This is not a good idea - first mechanism that supports a given
 	 * name type is picked up; later on the caller can request a
 	 * different mechanism. So we don't determine the mechanism here. Now
 	 * the user level and kernel level import_name routine looks similar
 	 * except the kernel routine makes a copy of the nametype structure. We
 	 * do however make this an MN for names of GSS_C_NT_EXPORT_NAME type.
 	 */
 	if (input_name_type != GSS_C_NULL_OID &&
 	    g_OID_equal(input_name_type, GSS_C_NT_EXPORT_NAME)) {
 		major_status = importExportName(minor_status, union_name);
 		if (major_status != GSS_S_COMPLETE)
 			goto allocation_failure;
 	}

 	*output_name = (gss_name_t)union_name;
 	return (GSS_S_COMPLETE);

 allocation_failure:
 	if (union_name) {
 		if (union_name->external_name) {
 			if (union_name->external_name->value)
 				free(union_name->external_name->value);
 			free(union_name->external_name);
 		}
 		if (union_name->name_type)
 			(void) generic_gss_release_oid(&tmp,
 						    &union_name->name_type);
 		if (union_name->mech_name)
 			(void) __gss_release_internal_name(minor_status,
 						union_name->mech_type,
 						&union_name->mech_name);
 		if (union_name->mech_type)
 			(void) generic_gss_release_oid(&tmp,
 						    &union_name->mech_type);
 		free(union_name);
 	}
 	return (major_status);
 }


 /*
  * GSS export name constants
  */
 static const char *expNameTokId = "\x04\x01";
 static const int expNameTokIdLen = 2;
 static const int mechOidLenLen = 2;
 static const int nameTypeLenLen = 2;

 static OM_uint32
 importExportName(minor, unionName)
 OM_uint32 *minor;
 gss_union_name_t unionName;
 {
 	gss_OID_desc mechOid;
 	gss_buffer_desc expName;
 	unsigned char *buf;
 	gss_mechanism mech;
 	OM_uint32 major, mechOidLen, nameLen, curLength;
 	unsigned int bytes;

 	expName.value = unionName->external_name->value;
 	expName.length = unionName->external_name->length;

 	curLength = expNameTokIdLen + mechOidLenLen;
 	if (expName.length < curLength)
 		return (GSS_S_DEFECTIVE_TOKEN);

 	buf = (unsigned char *)expName.value;
 	if (memcmp(expNameTokId, buf, expNameTokIdLen) != 0)
 		return (GSS_S_DEFECTIVE_TOKEN);

 	buf += expNameTokIdLen;

 	/* extract the mechanism oid length */
 	mechOidLen = (*buf++ << 8);
 	mechOidLen |= (*buf++);
 	curLength += mechOidLen;
 	if (expName.length < curLength)
 		return (GSS_S_DEFECTIVE_TOKEN);
 	/*
 	 * The mechOid itself is encoded in DER format, OID Tag (0x06)
 	 * length and the value of mech_OID
 	 */
 	if (*buf++ != 0x06)
 		return (GSS_S_DEFECTIVE_TOKEN);

 	/*
 	 * mechoid Length is encoded twice; once in 2 bytes as
 	 * explained in RFC2743 (under mechanism independent exported
 	 * name object format) and once using DER encoding
 	 *
 	 * We verify both lengths.
 	 */

 	mechOid.length = get_der_length(&buf,
 				(expName.length - curLength), &bytes);
 	mechOid.elements = (void *)buf;

 	/*
 	 * 'bytes' is the length of the DER length, '1' is for the DER
 	 * tag for OID
 	 */
 	if ((bytes + mechOid.length + 1) != mechOidLen)
 		return (GSS_S_DEFECTIVE_TOKEN);

 	buf += mechOid.length;
 	if ((mech = __gss_get_mechanism(&mechOid)) == NULL)
 		return (GSS_S_BAD_MECH);

 	if (mech->gss_import_name == NULL)
 		return (GSS_S_UNAVAILABLE);

 	/*
 	 * we must now determine if we should unwrap the name ourselves
 	 * or make the mechanism do it - we should only unwrap it
 	 * if we create it; so if mech->gss_export_name == NULL, we must
 	 * have created it.
 	 */
 	if (mech->gss_export_name) {
 		major = mech->gss_import_name(mech->context, minor,
 					    &expName,
 					    (gss_OID)GSS_C_NT_EXPORT_NAME,
 					    &unionName->mech_name);
 		if (major != GSS_S_COMPLETE)
 			map_error(minor, mech);
 		else {
 			major = generic_gss_copy_oid(minor, &mechOid,
 						    &unionName->mech_type);
 			if (major != GSS_S_COMPLETE)
 				map_errcode(minor);
 		}
 		return (major);
 	}
 	/*
 	 * we must have exported the name - so we now need to reconstruct it
 	 * and call the mechanism to create it
 	 *
 	 * WARNING:	Older versions of __gss_export_internal_name() did
 	 *		not export names correctly, but now it does.  In
 	 *		order to stay compatible with existing exported
 	 *		names we must support names exported the broken
 	 *		way.
 	 *
 	 * Specifically, __gss_export_internal_name() used to include
 	 * the name type OID in the encoding of the exported MN.
 	 * Additionally, the Kerberos V mech used to make display names
 	 * that included a null terminator which was counted in the
 	 * display name gss_buffer_desc.
 	 */
 	curLength += 4;		/* 4 bytes for name len */
 	if (expName.length < curLength)
 		return (GSS_S_DEFECTIVE_TOKEN);

 	/* next 4 bytes in the name are the name length */
 	nameLen = (*buf++) << 24;
 	nameLen |= (*buf++ << 16);
 	nameLen |= (*buf++ << 8);
 	nameLen |= (*buf++);

 	/*
 	 * we use < here because bad code in rpcsec_gss rounds up exported
 	 * name token lengths and pads with nulls, otherwise != would be
 	 * appropriate
 	 */
 	curLength += nameLen;   /* this is the total length */
 	if (expName.length < curLength)
 		return (GSS_S_DEFECTIVE_TOKEN);

 	/*
 	 * We detect broken exported names here: they always start with
 	 * a two-octet network-byte order OID length, which is always
 	 * less than 256 bytes, so the first octet of the length is
 	 * always '\0', which is not allowed in GSS-API display names
 	 * (or never occurs in them anyways).  Of course, the OID
 	 * shouldn't be there, but it is.  After the OID (sans DER tag
 	 * and length) there's the name itself, though null-terminated;
 	 * this null terminator should also not be there, but it is.
 	 */
 	if (nameLen > 0 && *buf == '\0') {
 		OM_uint32 nameTypeLen;
 		/* next two bytes are the name oid */
 		if (nameLen < nameTypeLenLen)
 			return (GSS_S_DEFECTIVE_TOKEN);

 		nameLen -= nameTypeLenLen;

 		nameTypeLen = (*buf++) << 8;
 		nameTypeLen |= (*buf++);

 		if (nameLen < nameTypeLen)
 			return (GSS_S_DEFECTIVE_TOKEN);

 		buf += nameTypeLen;
 		nameLen -= nameTypeLen;

 		/*
 		 * adjust for expected null terminator that should
 		 * really not be there
 		 */
 		if (nameLen > 0 && *(buf + nameLen - 1) == '\0')
 			nameLen--;
 	}

 	/*
 	 * Can a name be null?  Let the mech decide.
 	 *
 	 * NOTE: We use GSS_C_NULL_OID as the name type when importing
 	 *	 the unwrapped name.  Presumably the exported name had,
 	 *	 prior to being exported been obtained in such a way
 	 *	 that it has been properly perpared ("canonicalized," in
 	 *	 GSS-API terms) accroding to some name type; we cannot
 	 *	 tell what that name type was now, but the name should
 	 *	 need no further preparation other than the lowest
 	 *	 common denominator afforded by the mech to names
 	 *	 imported with GSS_C_NULL_OID.  For the Kerberos V mech
 	 *	 this means doing less busywork too (particularly once
 	 *	 IDN is thrown in with Kerberos V extensions).
 	 */
 	expName.length = nameLen;
 	expName.value = nameLen ? (void *)buf : NULL;
 	major = mech->gss_import_name(mech->context, minor, &expName,
 			    GSS_C_NULL_OID, &unionName->mech_name);
 	if (major != GSS_S_COMPLETE) {
 		map_error(minor, mech);
 		return (major);
 	}

 	major = generic_gss_copy_oid(minor, &mechOid, &unionName->mech_type);
 	if (major != GSS_S_COMPLETE) {
 		map_errcode(minor);
 	}
 	return (major);
 } /* importExportName */
	/*
	* CDDL HEADER START
	*
	* The contents of this file are subject to the terms of the
	* Common Development and Distribution License (the "License").
	* You may not use this file except in compliance with the License.
	*
	* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
	* or http://www.opensolaris.org/os/licensing.
	* See the License for the specific language governing permissions
	* and limitations under the License.
	*
	* When distributing Covered Code, include this CDDL HEADER in each
	* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
	* If applicable, add the following below this CDDL HEADER, with the
	* fields enclosed by brackets "[]" replaced with your own identifying
	* information: Portions Copyright [yyyy] [name of copyright owner]
	*
	* CDDL HEADER END
	*/
	/*
	* Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
	*/

	/*
	* glue routine gss_import_name
	*
	*/

	#include <mechglueP.h>
	#include "gssapiP_generic.h"
	#include <stdio.h>
	#ifdef HAVE_STDLIB_H
	#include <stdlib.h>
	#endif
	#include <string.h>
	#include <errno.h>

	extern int
	get_der_length(unsigned char *, unsigned int, unsigned int );

	/* local function to import GSS_C_EXPORT_NAME names */
	static OM_uint32 importExportName(OM_uint32 *, gss_union_name_t);

	static OM_uint32
	val_imp_name_args(
	OM_uint32 *minor_status,
	gss_buffer_t input_name_buffer,
	gss_name_t *output_name)
	{

	/* Initialize outputs. */

	if (minor_status != NULL)
	*minor_status = 0;

	if (output_name != NULL)
	*output_name = GSS_C_NO_NAME;

	/* Validate arguments. */

	if (minor_status == NULL)
	return (GSS_S_CALL_INACCESSIBLE_WRITE);

	if (output_name == NULL)
	return (GSS_S_CALL_INACCESSIBLE_WRITE);

	if (input_name_buffer == GSS_C_NO_BUFFER)
	return (GSS_S_CALL_INACCESSIBLE_READ \| GSS_S_BAD_NAME);

	if (GSS_EMPTY_BUFFER(input_name_buffer))
	return (GSS_S_CALL_INACCESSIBLE_READ \| GSS_S_BAD_NAME);

	return (GSS_S_COMPLETE);
	}

	OM_uint32
	gss_import_name(minor_status,
	input_name_buffer,
	input_name_type,
	output_name)

	OM_uint32 *minor_status;
	const gss_buffer_t input_name_buffer;
	const gss_OID input_name_type;
	gss_name_t *output_name;
	{
	gss_union_name_t union_name;
	OM_uint32 major_status = GSS_S_FAILURE, tmp;

	major_status = val_imp_name_args(minor_status,
	input_name_buffer,
	output_name);
	if (major_status != GSS_S_COMPLETE)
	return (major_status);

	/*
	* First create the union name struct that will hold the external
	* name and the name type.
	*/
	union_name = (gss_union_name_t)malloc(sizeof (gss_union_name_desc));
	if (!union_name)
	return (GSS_S_FAILURE);

	union_name->mech_type = 0;
	union_name->mech_name = 0;
	union_name->name_type = 0;
	union_name->external_name = 0;

	/*
	* All we do here is record the external name and name_type.
	* When the name is actually used, the underlying gss_import_name()
	* is called for the appropriate mechanism. The exception to this
	* rule is when the name of GSS_C_NT_EXPORT_NAME type. If that is
	* the case, then we make it MN in this call.
	*/
	major_status = gssint_create_copy_buffer(input_name_buffer,
	&union_name->external_name, 0);
	if (major_status != GSS_S_COMPLETE) {
	free(union_name);
	return (major_status);
	}

	if (input_name_type != GSS_C_NULL_OID) {
	major_status = generic_gss_copy_oid(minor_status,
	input_name_type,
	&union_name->name_type);
	if (major_status != GSS_S_COMPLETE) {
	map_errcode(minor_status);
	goto allocation_failure;
	}
	}

	/*
	* In MIT Distribution the mechanism is determined from the nametype;
	* This is not a good idea - first mechanism that supports a given
	* name type is picked up; later on the caller can request a
	* different mechanism. So we don't determine the mechanism here. Now
	* the user level and kernel level import_name routine looks similar
	* except the kernel routine makes a copy of the nametype structure. We
	* do however make this an MN for names of GSS_C_NT_EXPORT_NAME type.
	*/
	if (input_name_type != GSS_C_NULL_OID &&
	g_OID_equal(input_name_type, GSS_C_NT_EXPORT_NAME)) {
	major_status = importExportName(minor_status, union_name);
	if (major_status != GSS_S_COMPLETE)
	goto allocation_failure;
	}

	*output_name = (gss_name_t)union_name;
	return (GSS_S_COMPLETE);

	allocation_failure:
	if (union_name) {
	if (union_name->external_name) {
	if (union_name->external_name->value)
	free(union_name->external_name->value);
	free(union_name->external_name);
	}
	if (union_name->name_type)
	(void) generic_gss_release_oid(&tmp,
	&union_name->name_type);
	if (union_name->mech_name)
	(void) __gss_release_internal_name(minor_status,
	union_name->mech_type,
	&union_name->mech_name);
	if (union_name->mech_type)
	(void) generic_gss_release_oid(&tmp,
	&union_name->mech_type);
	free(union_name);
	}
	return (major_status);
	}


	/*
	* GSS export name constants
	*/
	static const char *expNameTokId = "\x04\x01";
	static const int expNameTokIdLen = 2;
	static const int mechOidLenLen = 2;
	static const int nameTypeLenLen = 2;

	static OM_uint32
	importExportName(minor, unionName)
	OM_uint32 *minor;
	gss_union_name_t unionName;
	{
	gss_OID_desc mechOid;
	gss_buffer_desc expName;
	unsigned char *buf;
	gss_mechanism mech;
	OM_uint32 major, mechOidLen, nameLen, curLength;
	unsigned int bytes;

	expName.value = unionName->external_name->value;
	expName.length = unionName->external_name->length;

	curLength = expNameTokIdLen + mechOidLenLen;
	if (expName.length < curLength)
	return (GSS_S_DEFECTIVE_TOKEN);

	buf = (unsigned char *)expName.value;
	if (memcmp(expNameTokId, buf, expNameTokIdLen) != 0)
	return (GSS_S_DEFECTIVE_TOKEN);

	buf += expNameTokIdLen;

	/* extract the mechanism oid length */
	mechOidLen = (*buf++ << 8);
	mechOidLen \|= (*buf++);
	curLength += mechOidLen;
	if (expName.length < curLength)
	return (GSS_S_DEFECTIVE_TOKEN);
	/*
	* The mechOid itself is encoded in DER format, OID Tag (0x06)
	* length and the value of mech_OID
	*/
	if (*buf++ != 0x06)
	return (GSS_S_DEFECTIVE_TOKEN);

	/*
	* mechoid Length is encoded twice; once in 2 bytes as
	* explained in RFC2743 (under mechanism independent exported
	* name object format) and once using DER encoding
	*
	* We verify both lengths.
	*/

	mechOid.length = get_der_length(&buf,
	(expName.length - curLength), &bytes);
	mechOid.elements = (void *)buf;

	/*
	* 'bytes' is the length of the DER length, '1' is for the DER
	* tag for OID
	*/
	if ((bytes + mechOid.length + 1) != mechOidLen)
	return (GSS_S_DEFECTIVE_TOKEN);

	buf += mechOid.length;
	if ((mech = __gss_get_mechanism(&mechOid)) == NULL)
	return (GSS_S_BAD_MECH);

	if (mech->gss_import_name == NULL)
	return (GSS_S_UNAVAILABLE);

	/*
	* we must now determine if we should unwrap the name ourselves
	* or make the mechanism do it - we should only unwrap it
	* if we create it; so if mech->gss_export_name == NULL, we must
	* have created it.
	*/
	if (mech->gss_export_name) {
	major = mech->gss_import_name(mech->context, minor,
	&expName,
	(gss_OID)GSS_C_NT_EXPORT_NAME,
	&unionName->mech_name);
	if (major != GSS_S_COMPLETE)
	map_error(minor, mech);
	else {
	major = generic_gss_copy_oid(minor, &mechOid,
	&unionName->mech_type);
	if (major != GSS_S_COMPLETE)
	map_errcode(minor);
	}
	return (major);
	}
	/*
	* we must have exported the name - so we now need to reconstruct it
	* and call the mechanism to create it
	*
	* WARNING: Older versions of __gss_export_internal_name() did
	* not export names correctly, but now it does. In
	* order to stay compatible with existing exported
	* names we must support names exported the broken
	* way.
	*
	* Specifically, __gss_export_internal_name() used to include
	* the name type OID in the encoding of the exported MN.
	* Additionally, the Kerberos V mech used to make display names
	* that included a null terminator which was counted in the
	* display name gss_buffer_desc.
	*/
	curLength += 4; /* 4 bytes for name len */
	if (expName.length < curLength)
	return (GSS_S_DEFECTIVE_TOKEN);

	/* next 4 bytes in the name are the name length */
	nameLen = (*buf++) << 24;
	nameLen \|= (*buf++ << 16);
	nameLen \|= (*buf++ << 8);
	nameLen \|= (*buf++);

	/*
	* we use < here because bad code in rpcsec_gss rounds up exported
	* name token lengths and pads with nulls, otherwise != would be
	* appropriate
	*/
	curLength += nameLen; /* this is the total length */
	if (expName.length < curLength)
	return (GSS_S_DEFECTIVE_TOKEN);

	/*
	* We detect broken exported names here: they always start with
	* a two-octet network-byte order OID length, which is always
	* less than 256 bytes, so the first octet of the length is
	* always '\0', which is not allowed in GSS-API display names
	* (or never occurs in them anyways). Of course, the OID
	* shouldn't be there, but it is. After the OID (sans DER tag
	* and length) there's the name itself, though null-terminated;
	* this null terminator should also not be there, but it is.
	*/
	if (nameLen > 0 && *buf == '\0') {
	OM_uint32 nameTypeLen;
	/* next two bytes are the name oid */
	if (nameLen < nameTypeLenLen)
	return (GSS_S_DEFECTIVE_TOKEN);

	nameLen -= nameTypeLenLen;

	nameTypeLen = (*buf++) << 8;
	nameTypeLen \|= (*buf++);

	if (nameLen < nameTypeLen)
	return (GSS_S_DEFECTIVE_TOKEN);

	buf += nameTypeLen;
	nameLen -= nameTypeLen;

	/*
	* adjust for expected null terminator that should
	* really not be there
	*/
	if (nameLen > 0 && *(buf + nameLen - 1) == '\0')
	nameLen--;
	}

	/*
	* Can a name be null? Let the mech decide.
	*
	* NOTE: We use GSS_C_NULL_OID as the name type when importing
	* the unwrapped name. Presumably the exported name had,
	* prior to being exported been obtained in such a way
	* that it has been properly perpared ("canonicalized," in
	* GSS-API terms) accroding to some name type; we cannot
	* tell what that name type was now, but the name should
	* need no further preparation other than the lowest
	* common denominator afforded by the mech to names
	* imported with GSS_C_NULL_OID. For the Kerberos V mech
	* this means doing less busywork too (particularly once
	* IDN is thrown in with Kerberos V extensions).
	*/
	expName.length = nameLen;
	expName.value = nameLen ? (void *)buf : NULL;
	major = mech->gss_import_name(mech->context, minor, &expName,
	GSS_C_NULL_OID, &unionName->mech_name);
	if (major != GSS_S_COMPLETE) {
	map_error(minor, mech);
	return (major);
	}

	major = generic_gss_copy_oid(minor, &mechOid, &unionName->mech_type);
	if (major != GSS_S_COMPLETE) {
	map_errcode(minor);
	}
	return (major);
	} /* importExportName */