[deliverable/linux.git] / net / sunrpc / auth_unix.c

/*
 * linux/net/sunrpc/auth_unix.c
 *
 * UNIX-style authentication; no AUTH_SHORT support
 *
 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
 */

#include <linux/types.h>
#include <linux/sched.h>
#include <linux/module.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/auth.h>

#define NFS_NGROUPS	16

struct unx_cred {
	struct rpc_cred		uc_base;
	gid_t			uc_gid;
	gid_t			uc_gids[NFS_NGROUPS];
};
#define uc_uid			uc_base.cr_uid
#define uc_count		uc_base.cr_count
#define uc_flags		uc_base.cr_flags
#define uc_expire		uc_base.cr_expire

#define UNX_CRED_EXPIRE		(60 * HZ)

#define UNX_WRITESLACK		(21 + (UNX_MAXNODENAME >> 2))

#ifdef RPC_DEBUG
# define RPCDBG_FACILITY	RPCDBG_AUTH
#endif

static struct rpc_auth		unix_auth;
static struct rpc_cred_cache	unix_cred_cache;
static struct rpc_credops	unix_credops;

static struct rpc_auth *
unx_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
{
	dprintk("RPC:       creating UNIX authenticator for client %p\n",
			clnt);
	if (atomic_inc_return(&unix_auth.au_count) == 0)
		unix_cred_cache.nextgc = jiffies + (unix_cred_cache.expire >> 1);
	return &unix_auth;
}

static void
unx_destroy(struct rpc_auth *auth)
{
	dprintk("RPC:       destroying UNIX authenticator %p\n", auth);
	rpcauth_free_credcache(auth);
}

/*
 * Lookup AUTH_UNIX creds for current process
 */
static struct rpc_cred *
unx_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
{
	return rpcauth_lookup_credcache(auth, acred, flags);
}

static struct rpc_cred *
unx_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
{
	struct unx_cred	*cred;
	int		i;

	dprintk("RPC:       allocating UNIX cred for uid %d gid %d\n",
			acred->uid, acred->gid);

	if (!(cred = kmalloc(sizeof(*cred), GFP_KERNEL)))
		return ERR_PTR(-ENOMEM);

	atomic_set(&cred->uc_count, 1);
	cred->uc_flags = RPCAUTH_CRED_UPTODATE;
	if (flags & RPCAUTH_LOOKUP_ROOTCREDS) {
		cred->uc_uid = 0;
		cred->uc_gid = 0;
		cred->uc_gids[0] = NOGROUP;
	} else {
		int groups = acred->group_info->ngroups;
		if (groups > NFS_NGROUPS)
			groups = NFS_NGROUPS;

		cred->uc_uid = acred->uid;
		cred->uc_gid = acred->gid;
		for (i = 0; i < groups; i++)
			cred->uc_gids[i] = GROUP_AT(acred->group_info, i);
		if (i < NFS_NGROUPS)
		  cred->uc_gids[i] = NOGROUP;
	}
	cred->uc_base.cr_ops = &unix_credops;

	return (struct rpc_cred *) cred;
}

static void
unx_destroy_cred(struct rpc_cred *cred)
{
	kfree(cred);
}

/*
 * Match credentials against current process creds.
 * The root_override argument takes care of cases where the caller may
 * request root creds (e.g. for NFS swapping).
 */
static int
unx_match(struct auth_cred *acred, struct rpc_cred *rcred, int flags)
{
	struct unx_cred	*cred = (struct unx_cred *) rcred;
	int		i;

	if (!(flags & RPCAUTH_LOOKUP_ROOTCREDS)) {
		int groups;

		if (cred->uc_uid != acred->uid
		 || cred->uc_gid != acred->gid)
			return 0;

		groups = acred->group_info->ngroups;
		if (groups > NFS_NGROUPS)
			groups = NFS_NGROUPS;
		for (i = 0; i < groups ; i++)
			if (cred->uc_gids[i] != GROUP_AT(acred->group_info, i))
				return 0;
		return 1;
	}
	return (cred->uc_uid == 0
	     && cred->uc_gid == 0
	     && cred->uc_gids[0] == (gid_t) NOGROUP);
}

/*
 * Marshal credentials.
 * Maybe we should keep a cached credential for performance reasons.
 */
static __be32 *
unx_marshal(struct rpc_task *task, __be32 *p)
{
	struct rpc_clnt	*clnt = task->tk_client;
	struct unx_cred	*cred = (struct unx_cred *) task->tk_msg.rpc_cred;
	__be32		*base, *hold;
	int		i;

	*p++ = htonl(RPC_AUTH_UNIX);
	base = p++;
	*p++ = htonl(jiffies/HZ);

	/*
	 * Copy the UTS nodename captured when the client was created.
	 */
	p = xdr_encode_array(p, clnt->cl_nodename, clnt->cl_nodelen);

	*p++ = htonl((u32) cred->uc_uid);
	*p++ = htonl((u32) cred->uc_gid);
	hold = p++;
	for (i = 0; i < 16 && cred->uc_gids[i] != (gid_t) NOGROUP; i++)
		*p++ = htonl((u32) cred->uc_gids[i]);
	*hold = htonl(p - hold - 1);		/* gid array length */
	*base = htonl((p - base - 1) << 2);	/* cred length */

	*p++ = htonl(RPC_AUTH_NULL);
	*p++ = htonl(0);

	return p;
}

/*
 * Refresh credentials. This is a no-op for AUTH_UNIX
 */
static int
unx_refresh(struct rpc_task *task)
{
	task->tk_msg.rpc_cred->cr_flags |= RPCAUTH_CRED_UPTODATE;
	return 0;
}

static __be32 *
unx_validate(struct rpc_task *task, __be32 *p)
{
	rpc_authflavor_t	flavor;
	u32			size;

	flavor = ntohl(*p++);
	if (flavor != RPC_AUTH_NULL &&
	    flavor != RPC_AUTH_UNIX &&
	    flavor != RPC_AUTH_SHORT) {
		printk("RPC: bad verf flavor: %u\n", flavor);
		return NULL;
	}

	size = ntohl(*p++);
	if (size > RPC_MAX_AUTH_SIZE) {
		printk("RPC: giant verf size: %u\n", size);
		return NULL;
	}
	task->tk_auth->au_rslack = (size >> 2) + 2;
	p += (size >> 2);

	return p;
}

struct rpc_authops	authunix_ops = {
	.owner		= THIS_MODULE,
	.au_flavor	= RPC_AUTH_UNIX,
#ifdef RPC_DEBUG
	.au_name	= "UNIX",
#endif
	.create		= unx_create,
	.destroy	= unx_destroy,
	.lookup_cred	= unx_lookup_cred,
	.crcreate	= unx_create_cred,
};

static
struct rpc_cred_cache	unix_cred_cache = {
	.expire		= UNX_CRED_EXPIRE,
};

static
struct rpc_auth		unix_auth = {
	.au_cslack	= UNX_WRITESLACK,
	.au_rslack	= 2,			/* assume AUTH_NULL verf */
	.au_ops		= &authunix_ops,
	.au_flavor	= RPC_AUTH_UNIX,
	.au_count	= ATOMIC_INIT(0),
	.au_credcache	= &unix_cred_cache,
};

static
struct rpc_credops	unix_credops = {
	.cr_name	= "AUTH_UNIX",
	.crdestroy	= unx_destroy_cred,
	.crmatch	= unx_match,
	.crmarshal	= unx_marshal,
	.crrefresh	= unx_refresh,
	.crvalidate	= unx_validate,
};
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/net/sunrpc/auth_unix.c
	3	*
	4	* UNIX-style authentication; no AUTH_SHORT support
	5	*
	6	* Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
	7	*/
	8
	9	#include <linux/types.h>
	10	#include <linux/sched.h>
	11	#include <linux/module.h>
1da177e4 LT	12	#include <linux/sunrpc/clnt.h>
	13	#include <linux/sunrpc/auth.h>
	14
	15	#define NFS_NGROUPS 16
	16
	17	struct unx_cred {
	18	struct rpc_cred uc_base;
	19	gid_t uc_gid;
	20	gid_t uc_gids[NFS_NGROUPS];
	21	};
	22	#define uc_uid uc_base.cr_uid
	23	#define uc_count uc_base.cr_count
	24	#define uc_flags uc_base.cr_flags
	25	#define uc_expire uc_base.cr_expire
	26
	27	#define UNX_CRED_EXPIRE (60 * HZ)
	28
	29	#define UNX_WRITESLACK (21 + (UNX_MAXNODENAME >> 2))
	30
	31	#ifdef RPC_DEBUG
	32	# define RPCDBG_FACILITY RPCDBG_AUTH
	33	#endif
	34
	35	static struct rpc_auth unix_auth;
	36	static struct rpc_cred_cache unix_cred_cache;
	37	static struct rpc_credops unix_credops;
	38
	39	static struct rpc_auth *
	40	unx_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
	41	{
46121cf7 CL	42	dprintk("RPC: creating UNIX authenticator for client %p\n",
46121cf7 CL	43	clnt);
1da177e4 LT	44	if (atomic_inc_return(&unix_auth.au_count) == 0)
	45	unix_cred_cache.nextgc = jiffies + (unix_cred_cache.expire >> 1);
	46	return &unix_auth;
	47	}
	48
	49	static void
	50	unx_destroy(struct rpc_auth *auth)
	51	{
46121cf7	52	dprintk("RPC: destroying UNIX authenticator %p\n", auth);
1da177e4 LT	53	rpcauth_free_credcache(auth);
	54	}
	55
	56	/*
	57	* Lookup AUTH_UNIX creds for current process
	58	*/
	59	static struct rpc_cred *
	60	unx_lookup_cred(struct rpc_auth auth, struct auth_cred acred, int flags)
	61	{
	62	return rpcauth_lookup_credcache(auth, acred, flags);
	63	}
	64
	65	static struct rpc_cred *
	66	unx_create_cred(struct rpc_auth auth, struct auth_cred acred, int flags)
	67	{
	68	struct unx_cred *cred;
	69	int i;
	70
46121cf7 CL	71	dprintk("RPC: allocating UNIX cred for uid %d gid %d\n",
46121cf7 CL	72	acred->uid, acred->gid);
1da177e4	73
8b3a7005	74	if (!(cred = kmalloc(sizeof(*cred), GFP_KERNEL)))
1da177e4 LT	75	return ERR_PTR(-ENOMEM);
	76
	77	atomic_set(&cred->uc_count, 1);
	78	cred->uc_flags = RPCAUTH_CRED_UPTODATE;
8a317760	79	if (flags & RPCAUTH_LOOKUP_ROOTCREDS) {
1da177e4 LT	80	cred->uc_uid = 0;
	81	cred->uc_gid = 0;
	82	cred->uc_gids[0] = NOGROUP;
	83	} else {
	84	int groups = acred->group_info->ngroups;
	85	if (groups > NFS_NGROUPS)
	86	groups = NFS_NGROUPS;
	87
	88	cred->uc_uid = acred->uid;
	89	cred->uc_gid = acred->gid;
	90	for (i = 0; i < groups; i++)
	91	cred->uc_gids[i] = GROUP_AT(acred->group_info, i);
	92	if (i < NFS_NGROUPS)
	93	cred->uc_gids[i] = NOGROUP;
	94	}
	95	cred->uc_base.cr_ops = &unix_credops;
	96
	97	return (struct rpc_cred *) cred;
	98	}
	99
	100	static void
	101	unx_destroy_cred(struct rpc_cred *cred)
	102	{
	103	kfree(cred);
	104	}
	105
	106	/*
	107	* Match credentials against current process creds.
	108	* The root_override argument takes care of cases where the caller may
	109	* request root creds (e.g. for NFS swapping).
	110	*/
	111	static int
8a317760	112	unx_match(struct auth_cred acred, struct rpc_cred rcred, int flags)
1da177e4 LT	113	{
	114	struct unx_cred cred = (struct unx_cred ) rcred;
	115	int i;
	116
8a317760	117	if (!(flags & RPCAUTH_LOOKUP_ROOTCREDS)) {
1da177e4 LT	118	int groups;
	119
	120	if (cred->uc_uid != acred->uid
	121	\|\| cred->uc_gid != acred->gid)
	122	return 0;
	123
	124	groups = acred->group_info->ngroups;
	125	if (groups > NFS_NGROUPS)
	126	groups = NFS_NGROUPS;
	127	for (i = 0; i < groups ; i++)
	128	if (cred->uc_gids[i] != GROUP_AT(acred->group_info, i))
	129	return 0;
	130	return 1;
	131	}
	132	return (cred->uc_uid == 0
	133	&& cred->uc_gid == 0
	134	&& cred->uc_gids[0] == (gid_t) NOGROUP);
	135	}
	136
	137	/*
	138	* Marshal credentials.
	139	* Maybe we should keep a cached credential for performance reasons.
	140	*/
d8ed029d AD	141	static __be32 *
d8ed029d AD	142	unx_marshal(struct rpc_task task, __be32 p)
1da177e4 LT	143	{
	144	struct rpc_clnt *clnt = task->tk_client;
	145	struct unx_cred cred = (struct unx_cred ) task->tk_msg.rpc_cred;
d8ed029d	146	__be32 base, hold;
1da177e4 LT	147	int i;
	148
	149	*p++ = htonl(RPC_AUTH_UNIX);
	150	base = p++;
	151	*p++ = htonl(jiffies/HZ);
	152
	153	/*
	154	* Copy the UTS nodename captured when the client was created.
	155	*/
	156	p = xdr_encode_array(p, clnt->cl_nodename, clnt->cl_nodelen);
	157
	158	*p++ = htonl((u32) cred->uc_uid);
	159	*p++ = htonl((u32) cred->uc_gid);
	160	hold = p++;
	161	for (i = 0; i < 16 && cred->uc_gids[i] != (gid_t) NOGROUP; i++)
	162	*p++ = htonl((u32) cred->uc_gids[i]);
	163	hold = htonl(p - hold - 1); / gid array length */
	164	base = htonl((p - base - 1) << 2); / cred length */
	165
	166	*p++ = htonl(RPC_AUTH_NULL);
	167	*p++ = htonl(0);
	168
	169	return p;
	170	}
	171
	172	/*
	173	* Refresh credentials. This is a no-op for AUTH_UNIX
	174	*/
	175	static int
	176	unx_refresh(struct rpc_task *task)
	177	{
	178	task->tk_msg.rpc_cred->cr_flags \|= RPCAUTH_CRED_UPTODATE;
	179	return 0;
	180	}
	181
d8ed029d AD	182	static __be32 *
d8ed029d AD	183	unx_validate(struct rpc_task task, __be32 p)
1da177e4 LT	184	{
	185	rpc_authflavor_t flavor;
	186	u32 size;
	187
	188	flavor = ntohl(*p++);
	189	if (flavor != RPC_AUTH_NULL &&
	190	flavor != RPC_AUTH_UNIX &&
	191	flavor != RPC_AUTH_SHORT) {
	192	printk("RPC: bad verf flavor: %u\n", flavor);
	193	return NULL;
	194	}
	195
	196	size = ntohl(*p++);
	197	if (size > RPC_MAX_AUTH_SIZE) {
	198	printk("RPC: giant verf size: %u\n", size);
	199	return NULL;
	200	}
	201	task->tk_auth->au_rslack = (size >> 2) + 2;
	202	p += (size >> 2);
	203
	204	return p;
	205	}
	206
	207	struct rpc_authops authunix_ops = {
	208	.owner = THIS_MODULE,
	209	.au_flavor = RPC_AUTH_UNIX,
	210	#ifdef RPC_DEBUG
	211	.au_name = "UNIX",
	212	#endif
	213	.create = unx_create,
	214	.destroy = unx_destroy,
	215	.lookup_cred = unx_lookup_cred,
	216	.crcreate = unx_create_cred,
	217	};
	218
	219	static
	220	struct rpc_cred_cache unix_cred_cache = {
	221	.expire = UNX_CRED_EXPIRE,
	222	};
	223
	224	static
	225	struct rpc_auth unix_auth = {
	226	.au_cslack = UNX_WRITESLACK,
	227	.au_rslack = 2, /* assume AUTH_NULL verf */
	228	.au_ops = &authunix_ops,
81039f1f	229	.au_flavor = RPC_AUTH_UNIX,
1da177e4 LT	230	.au_count = ATOMIC_INIT(0),
	231	.au_credcache = &unix_cred_cache,
	232	};
	233
	234	static
	235	struct rpc_credops unix_credops = {
	236	.cr_name = "AUTH_UNIX",
	237	.crdestroy = unx_destroy_cred,
	238	.crmatch = unx_match,
	239	.crmarshal = unx_marshal,
	240	.crrefresh = unx_refresh,
	241	.crvalidate = unx_validate,
	242	};