freebsd-skq/sys/rpc/rpcsec_gss.h

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Implement support for RPCSEC_GSS authentication to both the NFS client and server. This replaces the RPC implementation of the NFS client and server with the newer RPC implementation originally developed (actually ported from the userland sunrpc code) to support the NFS Lock Manager. I have tested this code extensively and I believe it is stable and that performance is at least equal to the legacy RPC implementation. The NFS code currently contains support for both the new RPC implementation and the older legacy implementation inherited from the original NFS codebase. The default is to use the new implementation - add the NFS_LEGACYRPC option to fall back to the old code. When I merge this support back to RELENG_7, I will probably change this so that users have to 'opt in' to get the new code. To use RPCSEC_GSS on either client or server, you must build a kernel which includes the KGSSAPI option and the crypto device. On the userland side, you must build at least a new libc, mountd, mount_nfs and gssd. You must install new versions of /etc/rc.d/gssd and /etc/rc.d/nfsd and add 'gssd_enable=YES' to /etc/rc.conf. As long as gssd is running, you should be able to mount an NFS filesystem from a server that requires RPCSEC_GSS authentication. The mount itself can happen without any kerberos credentials but all access to the filesystem will be denied unless the accessing user has a valid ticket file in the standard place (/tmp/krb5cc_<uid>). There is currently no support for situations where the ticket file is in a different place, such as when the user logged in via SSH and has delegated credentials from that login. This restriction is also present in Solaris and Linux. In theory, we could improve this in future, possibly using Brooks Davis' implementation of variant symlinks. Supporting RPCSEC_GSS on a server is nearly as simple. You must create service creds for the server in the form 'nfs/<fqdn>@<REALM>' and install them in /etc/krb5.keytab. The standard heimdal utility ktutil makes this fairly easy. After the service creds have been created, you can add a '-sec=krb5' option to /etc/exports and restart both mountd and nfsd. The only other difference an administrator should notice is that nfsd doesn't fork to create service threads any more. In normal operation, there will be two nfsd processes, one in userland waiting for TCP connections and one in the kernel handling requests. The latter process will create as many kthreads as required - these should be visible via 'top -H'. The code has some support for varying the number of service threads according to load but initially at least, nfsd uses a fixed number of threads according to the value supplied to its '-n' option. Sponsored by: Isilon Systems MFC after: 1 month
2008-11-03 10:38:00 +00:00
/*-
* Copyright (c) 2008 Doug Rabson
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _RPCSEC_GSS_H
#define _RPCSEC_GSS_H
#include <kgssapi/gssapi.h>
#ifndef MAX_GSS_MECH
#define MAX_GSS_MECH 64
#endif
/*
* Define the types of security service required for rpc_gss_seccreate().
*/
typedef enum {
rpc_gss_svc_default = 0,
rpc_gss_svc_none = 1,
rpc_gss_svc_integrity = 2,
rpc_gss_svc_privacy = 3
} rpc_gss_service_t;
/*
* Structure containing options for rpc_gss_seccreate().
*/
typedef struct {
int req_flags; /* GSS request bits */
int time_req; /* requested credential lifetime */
gss_cred_id_t my_cred; /* GSS credential */
gss_channel_bindings_t input_channel_bindings;
} rpc_gss_options_req_t;
/*
* Structure containing options returned by rpc_gss_seccreate().
*/
typedef struct {
int major_status;
int minor_status;
u_int rpcsec_version;
int ret_flags;
int time_req;
gss_ctx_id_t gss_context;
char actual_mechanism[MAX_GSS_MECH];
} rpc_gss_options_ret_t;
/*
* Client principal type. Used as an argument to
* rpc_gss_get_principal_name(). Also referenced by the
* rpc_gss_rawcred_t structure.
*/
typedef struct {
int len;
char name[1];
} *rpc_gss_principal_t;
/*
* Structure for raw credentials used by rpc_gss_getcred() and
* rpc_gss_set_callback().
*/
typedef struct {
u_int version; /* RPC version number */
const char *mechanism; /* security mechanism */
const char *qop; /* quality of protection */
rpc_gss_principal_t client_principal; /* client name */
const char *svc_principal; /* server name */
rpc_gss_service_t service; /* service type */
} rpc_gss_rawcred_t;
/*
* Unix credentials derived from raw credentials. Returned by
* rpc_gss_getcred().
*/
typedef struct {
uid_t uid; /* user ID */
gid_t gid; /* group ID */
short gidlen;
gid_t *gidlist; /* list of groups */
} rpc_gss_ucred_t;
/*
* Structure used to enforce a particular QOP and service.
*/
typedef struct {
bool_t locked;
rpc_gss_rawcred_t *raw_cred;
} rpc_gss_lock_t;
/*
* Callback structure used by rpc_gss_set_callback().
*/
typedef struct {
u_int program; /* RPC program number */
u_int version; /* RPC version number */
/* user defined callback */
bool_t (*callback)(struct svc_req *req,
gss_cred_id_t deleg,
gss_ctx_id_t gss_context,
rpc_gss_lock_t *lock,
void **cookie);
} rpc_gss_callback_t;
/*
* Structure used to return error information by rpc_gss_get_error()
*/
typedef struct {
int rpc_gss_error;
int system_error; /* same as errno */
} rpc_gss_error_t;
/*
* Values for rpc_gss_error
*/
#define RPC_GSS_ER_SUCCESS 0 /* no error */
#define RPC_GSS_ER_SYSTEMERROR 1 /* system error */
__BEGIN_DECLS
#ifdef _KERNEL
/*
* Set up a structure of entry points for the kgssapi module and inline
* functions named rpc_gss_XXX_call() to use them, so that the kgssapi
* module doesn't need to be loaded for the NFS modules to work using
* AUTH_SYS. The kgssapi modules will be loaded by the gssd(8) daemon
* when it is started up and the entry points will then be filled in.
*/
typedef AUTH *rpc_gss_secfind_ftype(CLIENT *clnt, struct ucred *cred,
const char *principal, gss_OID mech_oid,
rpc_gss_service_t service);
typedef void rpc_gss_secpurge_ftype(CLIENT *clnt);
typedef AUTH *rpc_gss_seccreate_ftype(CLIENT *clnt, struct ucred *cred,
const char *principal, const char *mechanism,
rpc_gss_service_t service, const char *qop,
rpc_gss_options_req_t *options_req,
rpc_gss_options_ret_t *options_ret);
typedef bool_t rpc_gss_set_defaults_ftype(AUTH *auth,
rpc_gss_service_t service, const char *qop);
typedef int rpc_gss_max_data_length_ftype(AUTH *handle,
int max_tp_unit_len);
typedef void rpc_gss_get_error_ftype(rpc_gss_error_t *error);
typedef bool_t rpc_gss_mech_to_oid_ftype(const char *mech, gss_OID *oid_ret);
typedef bool_t rpc_gss_oid_to_mech_ftype(gss_OID oid, const char **mech_ret);
typedef bool_t rpc_gss_qop_to_num_ftype(const char *qop, const char *mech,
u_int *num_ret);
typedef const char **rpc_gss_get_mechanisms_ftype(void);
typedef bool_t rpc_gss_get_versions_ftype(u_int *vers_hi, u_int *vers_lo);
typedef bool_t rpc_gss_is_installed_ftype(const char *mech);
typedef bool_t rpc_gss_set_svc_name_ftype(const char *principal,
const char *mechanism, u_int req_time, u_int program,
u_int version);
typedef void rpc_gss_clear_svc_name_ftype(u_int program, u_int version);
typedef bool_t rpc_gss_getcred_ftype(struct svc_req *req,
rpc_gss_rawcred_t **rcred,
rpc_gss_ucred_t **ucred, void **cookie);
typedef bool_t rpc_gss_set_callback_ftype(rpc_gss_callback_t *cb);
typedef void rpc_gss_clear_callback_ftype(rpc_gss_callback_t *cb);
typedef bool_t rpc_gss_get_principal_name_ftype(rpc_gss_principal_t *principal,
const char *mech, const char *name, const char *node,
const char *domain);
typedef int rpc_gss_svc_max_data_length_ftype(struct svc_req *req,
int max_tp_unit_len);
struct rpc_gss_entries {
rpc_gss_secfind_ftype *rpc_gss_secfind;
rpc_gss_secpurge_ftype *rpc_gss_secpurge;
rpc_gss_seccreate_ftype *rpc_gss_seccreate;
rpc_gss_set_defaults_ftype *rpc_gss_set_defaults;
rpc_gss_max_data_length_ftype *rpc_gss_max_data_length;
rpc_gss_get_error_ftype *rpc_gss_get_error;
rpc_gss_mech_to_oid_ftype *rpc_gss_mech_to_oid;
rpc_gss_oid_to_mech_ftype *rpc_gss_oid_to_mech;
rpc_gss_qop_to_num_ftype *rpc_gss_qop_to_num;
rpc_gss_get_mechanisms_ftype *rpc_gss_get_mechanisms;
rpc_gss_get_versions_ftype *rpc_gss_get_versions;
rpc_gss_is_installed_ftype *rpc_gss_is_installed;
rpc_gss_set_svc_name_ftype *rpc_gss_set_svc_name;
rpc_gss_clear_svc_name_ftype *rpc_gss_clear_svc_name;
rpc_gss_getcred_ftype *rpc_gss_getcred;
rpc_gss_set_callback_ftype *rpc_gss_set_callback;
rpc_gss_clear_callback_ftype *rpc_gss_clear_callback;
rpc_gss_get_principal_name_ftype *rpc_gss_get_principal_name;
rpc_gss_svc_max_data_length_ftype *rpc_gss_svc_max_data_length;
};
extern struct rpc_gss_entries rpc_gss_entries;
/* Functions to access the entry points. */
static __inline AUTH *
rpc_gss_secfind_call(CLIENT *clnt, struct ucred *cred, const char *principal,
gss_OID mech_oid, rpc_gss_service_t service)
{
AUTH *ret = NULL;
if (rpc_gss_entries.rpc_gss_secfind != NULL)
ret = (*rpc_gss_entries.rpc_gss_secfind)(clnt, cred, principal,
mech_oid, service);
return (ret);
}
static __inline void
rpc_gss_secpurge_call(CLIENT *clnt)
{
if (rpc_gss_entries.rpc_gss_secpurge != NULL)
(*rpc_gss_entries.rpc_gss_secpurge)(clnt);
}
static __inline AUTH *
rpc_gss_seccreate_call(CLIENT *clnt, struct ucred *cred, const char *principal,
const char *mechanism, rpc_gss_service_t service, const char *qop,
rpc_gss_options_req_t *options_req, rpc_gss_options_ret_t *options_ret)
{
AUTH *ret = NULL;
if (rpc_gss_entries.rpc_gss_seccreate != NULL)
ret = (*rpc_gss_entries.rpc_gss_seccreate)(clnt, cred,
principal, mechanism, service, qop, options_req,
options_ret);
return (ret);
}
static __inline bool_t
rpc_gss_set_defaults_call(AUTH *auth, rpc_gss_service_t service,
const char *qop)
{
bool_t ret = 1;
if (rpc_gss_entries.rpc_gss_set_defaults != NULL)
ret = (*rpc_gss_entries.rpc_gss_set_defaults)(auth, service,
qop);
return (ret);
}
static __inline int
rpc_gss_max_data_length_call(AUTH *handle, int max_tp_unit_len)
{
int ret = 0;
if (rpc_gss_entries.rpc_gss_max_data_length != NULL)
ret = (*rpc_gss_entries.rpc_gss_max_data_length)(handle,
max_tp_unit_len);
return (ret);
}
static __inline void
rpc_gss_get_error_call(rpc_gss_error_t *error)
{
if (rpc_gss_entries.rpc_gss_get_error != NULL)
(*rpc_gss_entries.rpc_gss_get_error)(error);
}
static __inline bool_t
rpc_gss_mech_to_oid_call(const char *mech, gss_OID *oid_ret)
{
bool_t ret = 1;
if (rpc_gss_entries.rpc_gss_mech_to_oid != NULL)
ret = (*rpc_gss_entries.rpc_gss_mech_to_oid)(mech, oid_ret);
return (ret);
}
static __inline bool_t
rpc_gss_oid_to_mech_call(gss_OID oid, const char **mech_ret)
{
bool_t ret = 1;
if (rpc_gss_entries.rpc_gss_oid_to_mech != NULL)
ret = (*rpc_gss_entries.rpc_gss_oid_to_mech)(oid, mech_ret);
return (ret);
}
static __inline bool_t
rpc_gss_qop_to_num_call(const char *qop, const char *mech, u_int *num_ret)
{
bool_t ret = 1;
if (rpc_gss_entries.rpc_gss_qop_to_num != NULL)
ret = (*rpc_gss_entries.rpc_gss_qop_to_num)(qop, mech, num_ret);
return (ret);
}
static __inline const char **
rpc_gss_get_mechanisms_call(void)
{
const char **ret = NULL;
if (rpc_gss_entries.rpc_gss_get_mechanisms != NULL)
ret = (*rpc_gss_entries.rpc_gss_get_mechanisms)();
return (ret);
}
static __inline bool_t
rpc_gss_get_versions_call(u_int *vers_hi, u_int *vers_lo)
{
bool_t ret = 1;
if (rpc_gss_entries.rpc_gss_get_versions != NULL)
ret = (*rpc_gss_entries.rpc_gss_get_versions)(vers_hi, vers_lo);
return (ret);
}
static __inline bool_t
rpc_gss_is_installed_call(const char *mech)
{
bool_t ret = 1;
if (rpc_gss_entries.rpc_gss_is_installed != NULL)
ret = (*rpc_gss_entries.rpc_gss_is_installed)(mech);
return (ret);
}
static __inline bool_t
rpc_gss_set_svc_name_call(const char *principal, const char *mechanism,
u_int req_time, u_int program, u_int version)
{
bool_t ret = 1;
if (rpc_gss_entries.rpc_gss_set_svc_name != NULL)
ret = (*rpc_gss_entries.rpc_gss_set_svc_name)(principal,
mechanism, req_time, program, version);
return (ret);
}
static __inline void
rpc_gss_clear_svc_name_call(u_int program, u_int version)
{
if (rpc_gss_entries.rpc_gss_clear_svc_name != NULL)
(*rpc_gss_entries.rpc_gss_clear_svc_name)(program, version);
}
static __inline bool_t
rpc_gss_getcred_call(struct svc_req *req, rpc_gss_rawcred_t **rcred,
rpc_gss_ucred_t **ucred, void **cookie)
{
bool_t ret = 1;
if (rpc_gss_entries.rpc_gss_getcred != NULL)
ret = (*rpc_gss_entries.rpc_gss_getcred)(req, rcred, ucred,
cookie);
return (ret);
}
static __inline bool_t
rpc_gss_set_callback_call(rpc_gss_callback_t *cb)
{
bool_t ret = 1;
if (rpc_gss_entries.rpc_gss_set_callback != NULL)
ret = (*rpc_gss_entries.rpc_gss_set_callback)(cb);
return (ret);
}
static __inline void
rpc_gss_clear_callback_call(rpc_gss_callback_t *cb)
{
if (rpc_gss_entries.rpc_gss_clear_callback != NULL)
(*rpc_gss_entries.rpc_gss_clear_callback)(cb);
}
static __inline bool_t
rpc_gss_get_principal_name_call(rpc_gss_principal_t *principal,
const char *mech, const char *name, const char *node, const char *domain)
{
bool_t ret = 1;
if (rpc_gss_entries.rpc_gss_get_principal_name != NULL)
ret = (*rpc_gss_entries.rpc_gss_get_principal_name)(principal,
mech, name, node, domain);
return (ret);
}
static __inline int
rpc_gss_svc_max_data_length_call(struct svc_req *req, int max_tp_unit_len)
{
int ret = 0;
if (rpc_gss_entries.rpc_gss_svc_max_data_length != NULL)
ret = (*rpc_gss_entries.rpc_gss_svc_max_data_length)(req,
max_tp_unit_len);
return (ret);
}
Implement support for RPCSEC_GSS authentication to both the NFS client and server. This replaces the RPC implementation of the NFS client and server with the newer RPC implementation originally developed (actually ported from the userland sunrpc code) to support the NFS Lock Manager. I have tested this code extensively and I believe it is stable and that performance is at least equal to the legacy RPC implementation. The NFS code currently contains support for both the new RPC implementation and the older legacy implementation inherited from the original NFS codebase. The default is to use the new implementation - add the NFS_LEGACYRPC option to fall back to the old code. When I merge this support back to RELENG_7, I will probably change this so that users have to 'opt in' to get the new code. To use RPCSEC_GSS on either client or server, you must build a kernel which includes the KGSSAPI option and the crypto device. On the userland side, you must build at least a new libc, mountd, mount_nfs and gssd. You must install new versions of /etc/rc.d/gssd and /etc/rc.d/nfsd and add 'gssd_enable=YES' to /etc/rc.conf. As long as gssd is running, you should be able to mount an NFS filesystem from a server that requires RPCSEC_GSS authentication. The mount itself can happen without any kerberos credentials but all access to the filesystem will be denied unless the accessing user has a valid ticket file in the standard place (/tmp/krb5cc_<uid>). There is currently no support for situations where the ticket file is in a different place, such as when the user logged in via SSH and has delegated credentials from that login. This restriction is also present in Solaris and Linux. In theory, we could improve this in future, possibly using Brooks Davis' implementation of variant symlinks. Supporting RPCSEC_GSS on a server is nearly as simple. You must create service creds for the server in the form 'nfs/<fqdn>@<REALM>' and install them in /etc/krb5.keytab. The standard heimdal utility ktutil makes this fairly easy. After the service creds have been created, you can add a '-sec=krb5' option to /etc/exports and restart both mountd and nfsd. The only other difference an administrator should notice is that nfsd doesn't fork to create service threads any more. In normal operation, there will be two nfsd processes, one in userland waiting for TCP connections and one in the kernel handling requests. The latter process will create as many kthreads as required - these should be visible via 'top -H'. The code has some support for varying the number of service threads according to load but initially at least, nfsd uses a fixed number of threads according to the value supplied to its '-n' option. Sponsored by: Isilon Systems MFC after: 1 month
2008-11-03 10:38:00 +00:00
AUTH *rpc_gss_secfind(CLIENT *clnt, struct ucred *cred,
const char *principal, gss_OID mech_oid, rpc_gss_service_t service);
void rpc_gss_secpurge(CLIENT *clnt);
#endif
AUTH *rpc_gss_seccreate(CLIENT *clnt, struct ucred *cred,
const char *principal, const char *mechanism, rpc_gss_service_t service,
const char *qop, rpc_gss_options_req_t *options_req,
rpc_gss_options_ret_t *options_ret);
bool_t rpc_gss_set_defaults(AUTH *auth, rpc_gss_service_t service,
const char *qop);
int rpc_gss_max_data_length(AUTH *handle, int max_tp_unit_len);
void rpc_gss_get_error(rpc_gss_error_t *error);
bool_t rpc_gss_mech_to_oid(const char *mech, gss_OID *oid_ret);
bool_t rpc_gss_oid_to_mech(gss_OID oid, const char **mech_ret);
bool_t rpc_gss_qop_to_num(const char *qop, const char *mech, u_int *num_ret);
const char **rpc_gss_get_mechanisms(void);
const char **rpc_gss_get_mech_info(const char *mech, rpc_gss_service_t *service);
bool_t rpc_gss_get_versions(u_int *vers_hi, u_int *vers_lo);
bool_t rpc_gss_is_installed(const char *mech);
bool_t rpc_gss_set_svc_name(const char *principal, const char *mechanism,
u_int req_time, u_int program, u_int version);
void rpc_gss_clear_svc_name(u_int program, u_int version);
bool_t rpc_gss_getcred(struct svc_req *req, rpc_gss_rawcred_t **rcred,
rpc_gss_ucred_t **ucred, void **cookie);
bool_t rpc_gss_set_callback(rpc_gss_callback_t *cb);
void rpc_gss_clear_callback(rpc_gss_callback_t *cb);
bool_t rpc_gss_get_principal_name(rpc_gss_principal_t *principal,
const char *mech, const char *name, const char *node, const char *domain);
int rpc_gss_svc_max_data_length(struct svc_req *req, int max_tp_unit_len);
/*
* Internal interface from the RPC implementation.
*/
#ifndef _KERNEL
bool_t __rpc_gss_wrap(AUTH *auth, void *header, size_t headerlen,
XDR* xdrs, xdrproc_t xdr_args, void *args_ptr);
bool_t __rpc_gss_unwrap(AUTH *auth, XDR* xdrs, xdrproc_t xdr_args,
void *args_ptr);
#endif
bool_t __rpc_gss_set_error(int rpc_gss_error, int system_error);
__END_DECLS
#endif /* !_RPCSEC_GSS_H */