CIFS_UPCALL_OBJ = client/cifs.upcall.o libsmb/clikrb5.o libsmb/clispnego.o \

		libsmb/asn1.o libsmb/nterr.o libsmb/dcerpc_err.o \

		libsmb/smbdes.o libsmb/smbencrypt.o libsmb/ntlmssp_parse.o \

		$(PARAM_OBJ) $(LIBNMB_OBJ) $(KRBCLIENT_OBJ) $(SECRETS_OBJ) \

		$(ERRORMAP_OBJ) $(RPC_PARSE_OBJ1) $(DOSERR_OBJ) $(LIB_DUMMY_OBJ)

bin/cifs.upcall@EXEEXT@: $(BINARY_PREREQS) $(CIFS_UPCALL_OBJ) $(LIBSMBCLIENT_OBJ1) $(LIB_OBJ) @BUILD_POPT@

	@echo Linking $@

	@$(CC) $(FLAGS) -o $@ $(CIFS_UPCALL_OBJ) $(DYNEXP) $(LDFLAGS) \

		-lkeyutils $(LIBSMBCLIENT_OBJ1) $(LIB_OBJ) \

		$(KRB5LIBS) $(LDAP_LIBS) $(POPT_LIBS) $(LIBS) 

installcifsupcall: @CIFSUPCALL_PROGS@

	@$(SHELL) $(srcdir)/script/installdirs.sh $(INSTALLPERMS) $(DESTDIR) $(SBINDIR)

	@$(SHELL) script/installbin.sh $(INSTALLPERMS) $(DESTDIR) $(prefix) $(SBINDIR) @CIFSUPCALL_PROGS@

uninstallcifsupcall:

	@$(SHELL) script/uninstallbin.sh $(INSTALLPERMS_BIN) $(DESTDIR) $(prefix) $(SBINDIR) @CIFSUPCALL_PROGS@

/*

 *   fs/cifs/cifs_spnego.h -- SPNEGO upcall management for CIFS

 *

 *   Copyright (c) 2007 Red Hat, Inc.

 *   Author(s): Jeff Layton (jlayton@redhat.com)

 *              Steve French (sfrench@us.ibm.com)

 *

 *   This library is free software; you can redistribute it and/or modify

 *   it under the terms of the GNU Lesser General Public License as published

 *   by the Free Software Foundation; either version 2.1 of the License, or

 *   (at your option) any later version.

 *

 *   This library is distributed in the hope that it will be useful,

 *   but WITHOUT ANY WARRANTY; without even the implied warranty of

 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See

 *   the GNU Lesser General Public License for more details.

 *

 *   You should have received a copy of the GNU Lesser General Public License

 *   along with this library; if not, write to the Free Software

 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

 */

#ifndef _CIFS_SPNEGO_H

#define _CIFS_SPNEGO_H

#define CIFS_SPNEGO_UPCALL_VERSION 2

/*

 * The version field should always be set to CIFS_SPNEGO_UPCALL_VERSION.

 * The flags field is for future use. The request-key callout should set

 * sesskey_len and secblob_len, and then concatenate the SessKey+SecBlob

 * and stuff it in the data field.

 */

struct cifs_spnego_msg {

	uint32_t version;

	uint32_t flags;

	uint32_t sesskey_len;

	uint32_t secblob_len;

	uint8_t data[1];

};

#ifdef __KERNEL__

extern struct key_type cifs_spnego_key_type;

#endif				/* KERNEL */

#endif				/* _CIFS_SPNEGO_H */

AC_SUBST(CIFSUPCALL_PROGS)

AC_SUBST(INSTALL_CIFSUPCALL)

AC_SUBST(UNINSTALL_CIFSUPCALL)

#################################################

# check for cifs.upcall support

AC_CHECK_HEADERS([keyutils.h], [HAVE_KEYUTILS_H=1], [HAVE_KEYUTILS_H=0])

CIFSUPCALL_PROGS=""

INSTALL_CIFSUPCALL=""

UNINSTALL_CIFSUPCALL=""

AC_MSG_CHECKING(whether to build cifs.upcall)

AC_ARG_WITH(cifsupcall,

[AS_HELP_STRING([--with-cifsupcall], [Include cifs.upcall (Linux only) support (default=yes)])],

[ case "$withval" in

  no)

	AC_MSG_RESULT(no)

	;;

  *)

	case "$host_os" in

	*linux*)

		if test x"$use_ads" != x"yes"; then

			AC_MSG_ERROR(ADS support should be enabled for building cifs.upcall)

		elif test x"$HAVE_KEYUTILS_H" != "x1"; then

			AC_MSG_ERROR(keyutils package is required for cifs.upcall)

		else

			AC_MSG_RESULT(yes)

			AC_DEFINE(WITH_CIFSUPCALL,1,[whether to build cifs.upcall])

			CIFSUPCALL_PROGS="bin/cifs.upcall"

			INSTALL_CIFSUPCALL="installcifsupcall"

			UNINSTALL_CIFSUPCALL="uninstallcifsupcall"

		fi

		;;

	*)

		AC_MSG_ERROR(not on a linux system!)

		;;

	esac

    ;;

  esac ],

[ case "$host_os" in

  *linux*)

        if test x"$use_ads" != x"yes"; then

                AC_MSG_WARN(ADS support should be enabled for building cifs.upcall)

        elif test x"$HAVE_KEYUTILS_H" != "x1"; then

                AC_MSG_WARN(keyutils package is required for cifs.upcall)

        else

                AC_MSG_RESULT(yes)

                AC_DEFINE(WITH_CIFSUPCALL,1,[whether to build cifs.upcall])

                CIFSUPCALL_PROGS="bin/cifs.upcall"

                INSTALL_CIFSUPCALL="installcifsupcall"

                UNINSTALL_CIFSUPCALL="uninstallcifsupcall"

        fi

        ;;

  *)

        AC_MSG_RESULT(no)

        ;;

  esac ]

)

extern const DATA_BLOB data_blob_null;

const DATA_BLOB data_blob_null = { NULL, 0, NULL };

/*

* CIFS user-space helper.

* Copyright (C) Igor Mammedov (niallain@gmail.com) 2007

*

* Used by /sbin/request-key for handling

* cifs upcall for kerberos authorization of access to share and

* cifs upcall for DFS srver name resolving (IPv4/IPv6 aware).

* You should have keyutils installed and add something like the

* following lines to /etc/request-key.conf file:

create cifs.spnego * * /usr/local/sbin/cifs.upcall %k

create dns_resolver * * /usr/local/sbin/cifs.upcall %k

* This program is free software; you can redistribute it and/or modify

* it under the terms of the GNU General Public License as published by

* the Free Software Foundation; either version 2 of the License, or

* (at your option) any later version.

* This program is distributed in the hope that it will be useful,

* but WITHOUT ANY WARRANTY; without even the implied warranty of

* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

* GNU General Public License for more details.

* You should have received a copy of the GNU General Public License

* along with this program; if not, write to the Free Software

* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

*/

#include "includes.h"

#include <keyutils.h>

#include "cifs_spnego.h"

const char *CIFSSPNEGO_VERSION = "1.2";

static const char *prog = "cifs.upcall";

typedef enum _secType {

	NONE = 0,

	KRB5,

	MS_KRB5

} secType_t;

/*

 * Prepares AP-REQ data for mechToken and gets session key

 * Uses credentials from cache. It will not ask for password

 * you should receive credentials for yuor name manually using

 * kinit or whatever you wish.

 *

 * in:

 * 	oid -		string with OID/ Could be OID_KERBEROS5

 * 			or OID_KERBEROS5_OLD

 * 	principal -	Service name.

 * 			Could be "cifs/FQDN" for KRB5 OID

 * 			or for MS_KRB5 OID style server principal

 * 			like "pdc$@YOUR.REALM.NAME"

 *

 * out:

 * 	secblob -	pointer for spnego wrapped AP-REQ data to be stored

 * 	sess_key-	pointer for SessionKey data to be stored

 *

 * ret: 0 - success, others - failure

*/

static int

handle_krb5_mech(const char *oid, const char *principal,

		     DATA_BLOB * secblob, DATA_BLOB * sess_key)

{

	int retval;

	DATA_BLOB tkt, tkt_wrapped;

	/* get a kerberos ticket for the service and extract the session key */

	retval = cli_krb5_get_ticket(principal, 0,

				     &tkt, sess_key, 0, NULL, NULL);

	if (retval)

		return retval;

	/* wrap that up in a nice GSS-API wrapping */

	tkt_wrapped = spnego_gen_krb5_wrap(tkt, TOK_ID_KRB_AP_REQ);

	/* and wrap that in a shiny SPNEGO wrapper */

	*secblob = gen_negTokenInit(oid, tkt_wrapped);

	data_blob_free(&tkt_wrapped);

	data_blob_free(&tkt);

	return retval;

}

#define DKD_HAVE_HOSTNAME	1

#define DKD_HAVE_VERSION	2

#define DKD_HAVE_SEC		4

#define DKD_HAVE_IPV4		8

#define DKD_HAVE_IPV6		16

#define DKD_HAVE_UID		32

#define DKD_MUSTHAVE_SET (DKD_HAVE_HOSTNAME|DKD_HAVE_VERSION|DKD_HAVE_SEC)

static int

decode_key_description(const char *desc, int *ver, secType_t * sec,

			   char **hostname, uid_t * uid)

{

	int retval = 0;

	char *pos;

	const char *tkn = desc;

	do {

		pos = index(tkn, ';');

		if (strncmp(tkn, "host=", 5) == 0) {

			int len;

			if (pos == NULL) {

				len = strlen(tkn);

			} else {

				len = pos - tkn;

			}

			len -= 4;

			SAFE_FREE(*hostname);

			*hostname = SMB_XMALLOC_ARRAY(char, len);

			strlcpy(*hostname, tkn + 5, len);

			retval |= DKD_HAVE_HOSTNAME;

		} else if (strncmp(tkn, "ipv4=", 5) == 0) {

			/* BB: do we need it if we have hostname already? */

		} else if (strncmp(tkn, "ipv6=", 5) == 0) {

			/* BB: do we need it if we have hostname already? */

		} else if (strncmp(tkn, "sec=", 4) == 0) {

			if (strncmp(tkn + 4, "krb5", 4) == 0) {

				retval |= DKD_HAVE_SEC;

				*sec = KRB5;

			} else if (strncmp(tkn + 4, "mskrb5", 6) == 0) {

				retval |= DKD_HAVE_SEC;

				*sec = MS_KRB5;

			}

		} else if (strncmp(tkn, "uid=", 4) == 0) {

			errno = 0;

			*uid = strtol(tkn + 4, NULL, 16);

			if (errno != 0) {

				syslog(LOG_WARNING, "Invalid uid format: %s",

				       strerror(errno));

				return 1;

			} else {

				retval |= DKD_HAVE_UID;

			}

		} else if (strncmp(tkn, "ver=", 4) == 0) {	/* if version */

			errno = 0;

			*ver = strtol(tkn + 4, NULL, 16);

			if (errno != 0) {

				syslog(LOG_WARNING,

				       "Invalid version format: %s",

				       strerror(errno));

				return 1;

			} else {

				retval |= DKD_HAVE_VERSION;

			}

		}

		if (pos == NULL)

			break;

		tkn = pos + 1;

	} while (tkn);

	return retval;

}

static int

cifs_resolver(const key_serial_t key, const char *key_descr)

{

	int c;

	struct addrinfo *addr;

	char ip[INET6_ADDRSTRLEN];

	void *p;

	const char *keyend = key_descr;

	/* skip next 4 ';' delimiters to get to description */

	for (c = 1; c <= 4; c++) {

		keyend = index(keyend+1, ';');

		if (!keyend) {

			syslog(LOG_WARNING, "invalid key description: %s",

					key_descr);

			return 1;

		}

	}

	keyend++;

	/* resolve name to ip */

	c = getaddrinfo(keyend, NULL, NULL, &addr);

	if (c) {

		syslog(LOG_WARNING, "unable to resolve hostname: %s [%s]",

				keyend, gai_strerror(c));

		return 1;

	}

	/* conver ip to string form */

	if (addr->ai_family == AF_INET) {

		p = &(((struct sockaddr_in *)addr->ai_addr)->sin_addr);

	} else {

		p = &(((struct sockaddr_in6 *)addr->ai_addr)->sin6_addr);

	}

	if (!inet_ntop(addr->ai_family, p, ip, sizeof(ip))) {

		syslog(LOG_WARNING, "%s: inet_ntop: %s",

				__FUNCTION__, strerror(errno));

		freeaddrinfo(addr);

		return 1;

	}

	/* setup key */

	c = keyctl_instantiate(key, ip, strlen(ip)+1, 0);

	if (c == -1) {

		syslog(LOG_WARNING, "%s: keyctl_instantiate: %s",

				__FUNCTION__, strerror(errno));

		freeaddrinfo(addr);

		return 1;

	}

	freeaddrinfo(addr);

	return 0;

}

static void

usage(void)

{

	syslog(LOG_WARNING, "Usage: %s [-c] [-v] key_serial", prog);

	fprintf(stderr, "Usage: %s [-c] [-v] key_serial\n", prog);

}

int main(const int argc, char *const argv[])

{

	struct cifs_spnego_msg *keydata = NULL;

	DATA_BLOB secblob = data_blob_null;

	DATA_BLOB sess_key = data_blob_null;

	secType_t sectype = NONE;

	key_serial_t key = 0;

	size_t datalen;

	long rc = 1;

	uid_t uid = 0;

	int kernel_upcall_version = 0;

	int c, use_cifs_service_prefix = 0;

	char *buf, *hostname = NULL;

	const char *oid;

	openlog(prog, 0, LOG_DAEMON);

	while ((c = getopt(argc, argv, "cv")) != -1) {

		switch (c) {

		case 'c':{

			use_cifs_service_prefix = 1;

			break;

			}

		case 'v':{

			printf("version: %s\n", CIFSSPNEGO_VERSION);

			goto out;

			}

		default:{

			syslog(LOG_WARNING, "unknown option: %c", c);

			goto out;

			}

		}

	}

	/* is there a key? */

	if (argc <= optind) {

		usage();

		goto out;

	}

	/* get key and keyring values */

	errno = 0;

	key = strtol(argv[optind], NULL, 10);

	if (errno != 0) {

		key = 0;

		syslog(LOG_WARNING, "Invalid key format: %s", strerror(errno));

		goto out;

	}

	rc = keyctl_describe_alloc(key, &buf);

	if (rc == -1) {

		syslog(LOG_WARNING, "keyctl_describe_alloc failed: %s",

		       strerror(errno));

		rc = 1;

		goto out;

	}

	if ((strncmp(buf, "cifs.resolver", sizeof("cifs.resolver")-1) == 0) ||

	    (strncmp(buf, "dns_resolver", sizeof("dns_resolver")-1) == 0)) {

		rc = cifs_resolver(key, buf);

		goto out;

	}

	rc = decode_key_description(buf, &kernel_upcall_version, &sectype,

				    &hostname, &uid);

	if ((rc & DKD_MUSTHAVE_SET) != DKD_MUSTHAVE_SET) {

		syslog(LOG_WARNING,

		       "unable to get from description necessary params");

		rc = 1;

		SAFE_FREE(buf);

		goto out;

	}

	SAFE_FREE(buf);

	if (kernel_upcall_version > CIFS_SPNEGO_UPCALL_VERSION) {

		syslog(LOG_WARNING,

		       "incompatible kernel upcall version: 0x%x",

		       kernel_upcall_version);

		rc = 1;

		goto out;

	}

	if (rc & DKD_HAVE_UID) {

		rc = setuid(uid);

		if (rc == -1) {

			syslog(LOG_WARNING, "setuid: %s", strerror(errno));

			goto out;

		}

	}

	/* BB: someday upcall SPNEGO blob could be checked here to decide

	 * what mech to use */

	// do mech specific authorization

	switch (sectype) {

	case MS_KRB5:

	case KRB5:{

			char *princ;

			size_t len;

			/* for "cifs/" service name + terminating 0 */

			len = strlen(hostname) + 5 + 1;

			princ = SMB_XMALLOC_ARRAY(char, len);

			if (!princ) {

				rc = 1;

				break;

			}

			if (use_cifs_service_prefix) {

				strlcpy(princ, "cifs/", len);

			} else {

				strlcpy(princ, "host/", len);

			}

			strlcpy(princ + 5, hostname, len - 5);

			if (sectype == MS_KRB5)

				oid = OID_KERBEROS5_OLD;

			else

				oid = OID_KERBEROS5;

			rc = handle_krb5_mech(oid, princ, &secblob, &sess_key);

			SAFE_FREE(princ);

			break;

		}

	default:{

			syslog(LOG_WARNING, "sectype: %d is not implemented",

			       sectype);

			rc = 1;

			break;

		}

	}

	if (rc) {

		goto out;

	}

	/* pack SecurityBLob and SessionKey into downcall packet */

	datalen =

	    sizeof(struct cifs_spnego_msg) + secblob.length + sess_key.length;

	keydata = (struct cifs_spnego_msg*)SMB_XMALLOC_ARRAY(char, datalen);

	if (!keydata) {

		rc = 1;

		goto out;

	}

	keydata->version = kernel_upcall_version;

	keydata->flags = 0;

	keydata->sesskey_len = sess_key.length;

	keydata->secblob_len = secblob.length;

	memcpy(&(keydata->data), sess_key.data, sess_key.length);

	memcpy(&(keydata->data) + keydata->sesskey_len,

	       secblob.data, secblob.length);

	/* setup key */

	rc = keyctl_instantiate(key, keydata, datalen, 0);

	if (rc == -1) {

		syslog(LOG_WARNING, "keyctl_instantiate: %s", strerror(errno));

		goto out;

	}

	/* BB: maybe we need use timeout for key: for example no more then

	 * ticket lifietime? */

	/* keyctl_set_timeout( key, 60); */

out:

	/*

	 * on error, negatively instantiate the key ourselves so that we can

	 * make sure the kernel doesn't hang it off of a searchable keyring

	 * and interfere with the next attempt to instantiate the key.

	 */

	if (rc != 0  && key == 0)

		keyctl_negate(key, 1, KEY_REQKEY_DEFL_DEFAULT);

	data_blob_free(&secblob);

	data_blob_free(&sess_key);

	SAFE_FREE(hostname);

	SAFE_FREE(keydata);

	return rc;

}

.\"     Title: cifs.upcall

.\"    Author: 

.\" Generator: DocBook XSL Stylesheets v1.73.1 <http://docbook.sf.net/>

.\"      Date: 09/18/2008

.\"    Manual: System Administration tools

.\"    Source: Samba 3.2

.\"

.TH "CIFS\.UPCALL" "8" "09/18/2008" "Samba 3\.2" "System Administration tools"

.\" disable hyphenation

.nh

.\" disable justification (adjust text to left margin only)

.ad l

.SH "NAME"

cifs.upcall - Userspace upcall helper for Common Internet File System (CIFS)

.SH "SYNOPSIS"

.HP 1

cifs\.upcall [\-c] [\-v] {keyid}

.SH "DESCRIPTION"

.PP

This tool is part of the

\fBsamba\fR(7)

suite\.

.PP

cifs\.upcall is a userspace helper program for the linux CIFS client filesystem\. There are a number of activities that the kernel cannot easily do itself\. This program is a callout program that does these things for the kernel and then returns the result\.

.PP

cifs\.upcall is generally intended to be run when the kernel calls request\-key(8)

for a particular key type\. While it can be run directly from the command\-line, it\'s not generally intended to be run that way\.

.SH "OPTIONS"

.PP

\-c

.RS 4

When handling a kerberos upcall, use a service principal that starts with "cifs/"\. The default is to use the "host/" service principal\.

.RE

.PP

\-v

.RS 4

Print version number and exit\.

.RE

.SH "CONFIGURATION FOR KEYCTL"

.PP

cifs\.upcall is designed to be called from the kernel via the request\-key callout program\. This requires that request\-key be told where and how to call this program\. The current cifs\.upcall program handles two different key types:

.PP

cifs\.spnego

.RS 4

This keytype is for retrieving kerberos session keys

.RE

.PP

dns_resolver

.RS 4

This key type is for resolving hostnames into IP addresses

.RE

.PP

To make this program useful for CIFS, you\'ll need to set up entries for them in request\-key\.conf(5)\. Here\'s an example of an entry for each key type:

.sp

.RS 4

.nf

#OPERATION  TYPE           D C PROGRAM ARG1 ARG2\.\.\.

#=========  =============  = = ==========================================

create	    cifs\.spnego    * * /usr/local/sbin/cifs\.upcall \-c %k

create      dns_resolver   * * /usr/local/sbin/cifs\.upcall %k

.fi

.RE

.PP

See

\fBrequest-key.conf5\fR()

for more info on each field\.

.SH "SEE ALSO"

.PP

\fBrequest-key.conf\fR(5),

\fBmount.cifs\fR(8)

.SH "AUTHOR"

.PP

Igor Mammedov wrote the cifs\.upcall program\.

.PP

Jeff Layton authored this manpage\.

.PP

The maintainer of the Linux CIFS VFS is Steve French\.

.PP

The

Linux CIFS Mailing list

is the preferred place to ask questions regarding these programs\.