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