[net-next-2.6.git] / fs / nfsd / nfs4idmap.c

/*
 *  fs/nfsd/nfs4idmap.c
 *
 *  Mapping of UID/GIDs to name and vice versa.
 *
 *  Copyright (c) 2002, 2003 The Regents of the University of
 *  Michigan.  All rights reserved.
 *
 *  Marius Aamodt Eriksen <marius@umich.edu>
 *
 *  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.
 *  3. Neither the name of the University nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED ``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 REGENTS 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.
 */

#include <linux/module.h>
#include <linux/init.h>

#include <linux/mm.h>
#include <linux/utsname.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/sunrpc/clnt.h>
#include <linux/nfs.h>
#include <linux/nfs4.h>
#include <linux/nfs_fs.h>
#include <linux/nfs_page.h>
#include <linux/smp_lock.h>
#include <linux/sunrpc/cache.h>
#include <linux/nfsd_idmap.h>
#include <linux/list.h>
#include <linux/time.h>
#include <linux/seq_file.h>
#include <linux/sunrpc/svcauth.h>

/*
 * Cache entry
 */

/*
 * XXX we know that IDMAP_NAMESZ < PAGE_SIZE, but it's ugly to rely on
 * that.
 */

#define IDMAP_TYPE_USER  0
#define IDMAP_TYPE_GROUP 1

struct ent {
	struct cache_head h;
	int               type;		       /* User / Group */
	uid_t             id;
	char              name[IDMAP_NAMESZ];
	char              authname[IDMAP_NAMESZ];
};

/* Common entry handling */

#define ENT_HASHBITS          8
#define ENT_HASHMAX           (1 << ENT_HASHBITS)
#define ENT_HASHMASK          (ENT_HASHMAX - 1)

static void
ent_init(struct cache_head *cnew, struct cache_head *citm)
{
	struct ent *new = container_of(cnew, struct ent, h);
	struct ent *itm = container_of(citm, struct ent, h);

	new->id = itm->id;
	new->type = itm->type;

	strlcpy(new->name, itm->name, sizeof(new->name));
	strlcpy(new->authname, itm->authname, sizeof(new->name));
}

static void
ent_put(struct kref *ref)
{
	struct ent *map = container_of(ref, struct ent, h.ref);
	kfree(map);
}

static struct cache_head *
ent_alloc(void)
{
	struct ent *e = kmalloc(sizeof(*e), GFP_KERNEL);
	if (e)
		return &e->h;
	else
		return NULL;
}

/*
 * ID -> Name cache
 */

static struct cache_head *idtoname_table[ENT_HASHMAX];

static uint32_t
idtoname_hash(struct ent *ent)
{
	uint32_t hash;

	hash = hash_str(ent->authname, ENT_HASHBITS);
	hash = hash_long(hash ^ ent->id, ENT_HASHBITS);

	/* Flip LSB for user/group */
	if (ent->type == IDMAP_TYPE_GROUP)
		hash ^= 1;

	return hash;
}

static void
idtoname_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
    int *blen)
{
 	struct ent *ent = container_of(ch, struct ent, h);
	char idstr[11];

	qword_add(bpp, blen, ent->authname);
	snprintf(idstr, sizeof(idstr), "%d", ent->id);
	qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
	qword_add(bpp, blen, idstr);

	(*bpp)[-1] = '\n';
}

static int
idtoname_match(struct cache_head *ca, struct cache_head *cb)
{
	struct ent *a = container_of(ca, struct ent, h);
	struct ent *b = container_of(cb, struct ent, h);

	return (a->id == b->id && a->type == b->type &&
	    strcmp(a->authname, b->authname) == 0);
}

static int
idtoname_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
{
	struct ent *ent;

	if (h == NULL) {
		seq_puts(m, "#domain type id [name]\n");
		return 0;
	}
	ent = container_of(h, struct ent, h);
	seq_printf(m, "%s %s %d", ent->authname,
			ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
			ent->id);
	if (test_bit(CACHE_VALID, &h->flags))
		seq_printf(m, " %s", ent->name);
	seq_printf(m, "\n");
	return 0;
}

static void
warn_no_idmapd(struct cache_detail *detail)
{
	printk("nfsd: nfsv4 idmapping failing: has idmapd %s?\n",
			detail->last_close? "died" : "not been started");
}


static int         idtoname_parse(struct cache_detail *, char *, int);
static struct ent *idtoname_lookup(struct ent *);
static struct ent *idtoname_update(struct ent *, struct ent *);

static struct cache_detail idtoname_cache = {
	.owner		= THIS_MODULE,
	.hash_size	= ENT_HASHMAX,
	.hash_table	= idtoname_table,
	.name		= "nfs4.idtoname",
	.cache_put	= ent_put,
	.cache_request	= idtoname_request,
	.cache_parse	= idtoname_parse,
	.cache_show	= idtoname_show,
	.warn_no_listener = warn_no_idmapd,
	.match		= idtoname_match,
	.init		= ent_init,
	.update		= ent_init,
	.alloc		= ent_alloc,
};

int
idtoname_parse(struct cache_detail *cd, char *buf, int buflen)
{
	struct ent ent, *res;
	char *buf1, *bp;
	int error = -EINVAL;

	if (buf[buflen - 1] != '\n')
		return (-EINVAL);
	buf[buflen - 1]= '\0';

	buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
	if (buf1 == NULL)
		return (-ENOMEM);

	memset(&ent, 0, sizeof(ent));

	/* Authentication name */
	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
		goto out;
	memcpy(ent.authname, buf1, sizeof(ent.authname));

	/* Type */
	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
		goto out;
	ent.type = strcmp(buf1, "user") == 0 ?
		IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;

	/* ID */
	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
		goto out;
	ent.id = simple_strtoul(buf1, &bp, 10);
	if (bp == buf1)
		goto out;

	/* expiry */
	ent.h.expiry_time = get_expiry(&buf);
	if (ent.h.expiry_time == 0)
		goto out;

	error = -ENOMEM;
	res = idtoname_lookup(&ent);
	if (!res)
		goto out;

	/* Name */
	error = qword_get(&buf, buf1, PAGE_SIZE);
	if (error == -EINVAL)
		goto out;
	if (error == -ENOENT)
		set_bit(CACHE_NEGATIVE, &ent.h.flags);
	else {
		if (error >= IDMAP_NAMESZ) {
			error = -EINVAL;
			goto out;
		}
		memcpy(ent.name, buf1, sizeof(ent.name));
	}
	error = -ENOMEM;
	res = idtoname_update(&ent, res);
	if (res == NULL)
		goto out;

	cache_put(&res->h, &idtoname_cache);

	error = 0;
out:
	kfree(buf1);

	return error;
}


static struct ent *
idtoname_lookup(struct ent *item)
{
	struct cache_head *ch = sunrpc_cache_lookup(&idtoname_cache,
						    &item->h,
						    idtoname_hash(item));
	if (ch)
		return container_of(ch, struct ent, h);
	else
		return NULL;
}

static struct ent *
idtoname_update(struct ent *new, struct ent *old)
{
	struct cache_head *ch = sunrpc_cache_update(&idtoname_cache,
						    &new->h, &old->h,
						    idtoname_hash(new));
	if (ch)
		return container_of(ch, struct ent, h);
	else
		return NULL;
}


/*
 * Name -> ID cache
 */

static struct cache_head *nametoid_table[ENT_HASHMAX];

static inline int
nametoid_hash(struct ent *ent)
{
	return hash_str(ent->name, ENT_HASHBITS);
}

static void
nametoid_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
    int *blen)
{
 	struct ent *ent = container_of(ch, struct ent, h);

	qword_add(bpp, blen, ent->authname);
	qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
	qword_add(bpp, blen, ent->name);

	(*bpp)[-1] = '\n';
}

static int
nametoid_match(struct cache_head *ca, struct cache_head *cb)
{
	struct ent *a = container_of(ca, struct ent, h);
	struct ent *b = container_of(cb, struct ent, h);

	return (a->type == b->type && strcmp(a->name, b->name) == 0 &&
	    strcmp(a->authname, b->authname) == 0);
}

static int
nametoid_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
{
	struct ent *ent;

	if (h == NULL) {
		seq_puts(m, "#domain type name [id]\n");
		return 0;
	}
	ent = container_of(h, struct ent, h);
	seq_printf(m, "%s %s %s", ent->authname,
			ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
			ent->name);
	if (test_bit(CACHE_VALID, &h->flags))
		seq_printf(m, " %d", ent->id);
	seq_printf(m, "\n");
	return 0;
}

static struct ent *nametoid_lookup(struct ent *);
static struct ent *nametoid_update(struct ent *, struct ent *);
static int         nametoid_parse(struct cache_detail *, char *, int);

static struct cache_detail nametoid_cache = {
	.owner		= THIS_MODULE,
	.hash_size	= ENT_HASHMAX,
	.hash_table	= nametoid_table,
	.name		= "nfs4.nametoid",
	.cache_put	= ent_put,
	.cache_request	= nametoid_request,
	.cache_parse	= nametoid_parse,
	.cache_show	= nametoid_show,
	.warn_no_listener = warn_no_idmapd,
	.match		= nametoid_match,
	.init		= ent_init,
	.update		= ent_init,
	.alloc		= ent_alloc,
};

static int
nametoid_parse(struct cache_detail *cd, char *buf, int buflen)
{
	struct ent ent, *res;
	char *buf1;
	int error = -EINVAL;

	if (buf[buflen - 1] != '\n')
		return (-EINVAL);
	buf[buflen - 1]= '\0';

	buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
	if (buf1 == NULL)
		return (-ENOMEM);

	memset(&ent, 0, sizeof(ent));

	/* Authentication name */
	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
		goto out;
	memcpy(ent.authname, buf1, sizeof(ent.authname));

	/* Type */
	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
		goto out;
	ent.type = strcmp(buf1, "user") == 0 ?
		IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;

	/* Name */
	error = qword_get(&buf, buf1, PAGE_SIZE);
	if (error <= 0 || error >= IDMAP_NAMESZ)
		goto out;
	memcpy(ent.name, buf1, sizeof(ent.name));

	/* expiry */
	ent.h.expiry_time = get_expiry(&buf);
	if (ent.h.expiry_time == 0)
		goto out;

	/* ID */
	error = get_int(&buf, &ent.id);
	if (error == -EINVAL)
		goto out;
	if (error == -ENOENT)
		set_bit(CACHE_NEGATIVE, &ent.h.flags);

	error = -ENOMEM;
	res = nametoid_lookup(&ent);
	if (res == NULL)
		goto out;
	res = nametoid_update(&ent, res);
	if (res == NULL)
		goto out;

	cache_put(&res->h, &nametoid_cache);
	error = 0;
out:
	kfree(buf1);

	return (error);
}


static struct ent *
nametoid_lookup(struct ent *item)
{
	struct cache_head *ch = sunrpc_cache_lookup(&nametoid_cache,
						    &item->h,
						    nametoid_hash(item));
	if (ch)
		return container_of(ch, struct ent, h);
	else
		return NULL;
}

static struct ent *
nametoid_update(struct ent *new, struct ent *old)
{
	struct cache_head *ch = sunrpc_cache_update(&nametoid_cache,
						    &new->h, &old->h,
						    nametoid_hash(new));
	if (ch)
		return container_of(ch, struct ent, h);
	else
		return NULL;
}

/*
 * Exported API
 */

void
nfsd_idmap_init(void)
{
	cache_register(&idtoname_cache);
	cache_register(&nametoid_cache);
}

void
nfsd_idmap_shutdown(void)
{
	if (cache_unregister(&idtoname_cache))
		printk(KERN_ERR "nfsd: failed to unregister idtoname cache\n");
	if (cache_unregister(&nametoid_cache))
		printk(KERN_ERR "nfsd: failed to unregister nametoid cache\n");
}

/*
 * Deferred request handling
 */

struct idmap_defer_req {
       struct cache_req		req;
       struct cache_deferred_req deferred_req;
       wait_queue_head_t	waitq;
       atomic_t			count;
};

static inline void
put_mdr(struct idmap_defer_req *mdr)
{
	if (atomic_dec_and_test(&mdr->count))
		kfree(mdr);
}

static inline void
get_mdr(struct idmap_defer_req *mdr)
{
	atomic_inc(&mdr->count);
}

static void
idmap_revisit(struct cache_deferred_req *dreq, int toomany)
{
	struct idmap_defer_req *mdr =
		container_of(dreq, struct idmap_defer_req, deferred_req);

	wake_up(&mdr->waitq);
	put_mdr(mdr);
}

static struct cache_deferred_req *
idmap_defer(struct cache_req *req)
{
	struct idmap_defer_req *mdr =
		container_of(req, struct idmap_defer_req, req);

	mdr->deferred_req.revisit = idmap_revisit;
	get_mdr(mdr);
	return (&mdr->deferred_req);
}

static inline int
do_idmap_lookup(struct ent *(*lookup_fn)(struct ent *), struct ent *key,
		struct cache_detail *detail, struct ent **item,
		struct idmap_defer_req *mdr)
{
	*item = lookup_fn(key);
	if (!*item)
		return -ENOMEM;
	return cache_check(detail, &(*item)->h, &mdr->req);
}

static inline int
do_idmap_lookup_nowait(struct ent *(*lookup_fn)(struct ent *),
			struct ent *key, struct cache_detail *detail,
			struct ent **item)
{
	int ret = -ENOMEM;

	*item = lookup_fn(key);
	if (!*item)
		goto out_err;
	ret = -ETIMEDOUT;
	if (!test_bit(CACHE_VALID, &(*item)->h.flags)
			|| (*item)->h.expiry_time < get_seconds()
			|| detail->flush_time > (*item)->h.last_refresh)
		goto out_put;
	ret = -ENOENT;
	if (test_bit(CACHE_NEGATIVE, &(*item)->h.flags))
		goto out_put;
	return 0;
out_put:
	cache_put(&(*item)->h, detail);
out_err:
	*item = NULL;
	return ret;
}

static int
idmap_lookup(struct svc_rqst *rqstp,
		struct ent *(*lookup_fn)(struct ent *), struct ent *key,
		struct cache_detail *detail, struct ent **item)
{
	struct idmap_defer_req *mdr;
	int ret;

	mdr = kzalloc(sizeof(*mdr), GFP_KERNEL);
	if (!mdr)
		return -ENOMEM;
	atomic_set(&mdr->count, 1);
	init_waitqueue_head(&mdr->waitq);
	mdr->req.defer = idmap_defer;
	ret = do_idmap_lookup(lookup_fn, key, detail, item, mdr);
	if (ret == -EAGAIN) {
		wait_event_interruptible_timeout(mdr->waitq,
			test_bit(CACHE_VALID, &(*item)->h.flags), 1 * HZ);
		ret = do_idmap_lookup_nowait(lookup_fn, key, detail, item);
	}
	put_mdr(mdr);
	return ret;
}

static int
idmap_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen,
		uid_t *id)
{
	struct ent *item, key = {
		.type = type,
	};
	int ret;

	if (namelen + 1 > sizeof(key.name))
		return -EINVAL;
	memcpy(key.name, name, namelen);
	key.name[namelen] = '\0';
	strlcpy(key.authname, rqstp->rq_client->name, sizeof(key.authname));
	ret = idmap_lookup(rqstp, nametoid_lookup, &key, &nametoid_cache, &item);
	if (ret == -ENOENT)
		ret = -ESRCH; /* nfserr_badname */
	if (ret)
		return ret;
	*id = item->id;
	cache_put(&item->h, &nametoid_cache);
	return 0;
}

static int
idmap_id_to_name(struct svc_rqst *rqstp, int type, uid_t id, char *name)
{
	struct ent *item, key = {
		.id = id,
		.type = type,
	};
	int ret;

	strlcpy(key.authname, rqstp->rq_client->name, sizeof(key.authname));
	ret = idmap_lookup(rqstp, idtoname_lookup, &key, &idtoname_cache, &item);
	if (ret == -ENOENT)
		return sprintf(name, "%u", id);
	if (ret)
		return ret;
	ret = strlen(item->name);
	BUG_ON(ret > IDMAP_NAMESZ);
	memcpy(name, item->name, ret);
	cache_put(&item->h, &idtoname_cache);
	return ret;
}

int
nfsd_map_name_to_uid(struct svc_rqst *rqstp, const char *name, size_t namelen,
		__u32 *id)
{
	return idmap_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, id);
}

int
nfsd_map_name_to_gid(struct svc_rqst *rqstp, const char *name, size_t namelen,
		__u32 *id)
{
	return idmap_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, id);
}

int
nfsd_map_uid_to_name(struct svc_rqst *rqstp, __u32 id, char *name)
{
	return idmap_id_to_name(rqstp, IDMAP_TYPE_USER, id, name);
}

int
nfsd_map_gid_to_name(struct svc_rqst *rqstp, __u32 id, char *name)
{
	return idmap_id_to_name(rqstp, IDMAP_TYPE_GROUP, id, name);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* fs/nfsd/nfs4idmap.c
	3	*
	4	* Mapping of UID/GIDs to name and vice versa.
	5	*
	6	* Copyright (c) 2002, 2003 The Regents of the University of
	7	* Michigan. All rights reserved.
	8	*
	9	* Marius Aamodt Eriksen <marius@umich.edu>
	10	*
	11	* Redistribution and use in source and binary forms, with or without
	12	* modification, are permitted provided that the following conditions
	13	* are met:
	14	*
	15	* 1. Redistributions of source code must retain the above copyright
	16	* notice, this list of conditions and the following disclaimer.
	17	* 2. Redistributions in binary form must reproduce the above copyright
	18	* notice, this list of conditions and the following disclaimer in the
	19	* documentation and/or other materials provided with the distribution.
	20	* 3. Neither the name of the University nor the names of its
	21	* contributors may be used to endorse or promote products derived
	22	* from this software without specific prior written permission.
	23	*
	24	* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
	25	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
	26	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
	27	* DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	28	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	29	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	30	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
	31	* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
	32	* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
	33	* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
	34	* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	35	*/
	36
1da177e4 LT	37	#include <linux/module.h>
	38	#include <linux/init.h>
	39
	40	#include <linux/mm.h>
	41	#include <linux/utsname.h>
	42	#include <linux/errno.h>
	43	#include <linux/string.h>
	44	#include <linux/sunrpc/clnt.h>
	45	#include <linux/nfs.h>
	46	#include <linux/nfs4.h>
	47	#include <linux/nfs_fs.h>
	48	#include <linux/nfs_page.h>
	49	#include <linux/smp_lock.h>
	50	#include <linux/sunrpc/cache.h>
	51	#include <linux/nfsd_idmap.h>
	52	#include <linux/list.h>
1da177e4 LT	53	#include <linux/time.h>
	54	#include <linux/seq_file.h>
	55	#include <linux/sunrpc/svcauth.h>
	56
	57	/*
	58	* Cache entry
	59	*/
	60
	61	/*
	62	* XXX we know that IDMAP_NAMESZ < PAGE_SIZE, but it's ugly to rely on
	63	* that.
	64	*/
	65
	66	#define IDMAP_TYPE_USER 0
	67	#define IDMAP_TYPE_GROUP 1
	68
	69	struct ent {
	70	struct cache_head h;
	71	int type; /* User / Group */
	72	uid_t id;
	73	char name[IDMAP_NAMESZ];
	74	char authname[IDMAP_NAMESZ];
	75	};
	76
1da177e4 LT	77	/* Common entry handling */
	78
	79	#define ENT_HASHBITS 8
	80	#define ENT_HASHMAX (1 << ENT_HASHBITS)
	81	#define ENT_HASHMASK (ENT_HASHMAX - 1)
	82
f9ecc921 N	83	static void
f9ecc921 N	84	ent_init(struct cache_head cnew, struct cache_head citm)
1da177e4	85	{
f9ecc921 N	86	struct ent *new = container_of(cnew, struct ent, h);
	87	struct ent *itm = container_of(citm, struct ent, h);
	88
1da177e4 LT	89	new->id = itm->id;
	90	new->type = itm->type;
	91
	92	strlcpy(new->name, itm->name, sizeof(new->name));
	93	strlcpy(new->authname, itm->authname, sizeof(new->name));
	94	}
	95
fd39ca9a	96	static void
baab935f	97	ent_put(struct kref *ref)
1da177e4	98	{
baab935f N	99	struct ent *map = container_of(ref, struct ent, h.ref);
baab935f N	100	kfree(map);
1da177e4 LT	101	}
1da177e4 LT	102
f9ecc921 N	103	static struct cache_head *
	104	ent_alloc(void)
	105	{
	106	struct ent e = kmalloc(sizeof(e), GFP_KERNEL);
	107	if (e)
	108	return &e->h;
	109	else
	110	return NULL;
	111	}
	112
1da177e4 LT	113	/*
	114	* ID -> Name cache
	115	*/
	116
	117	static struct cache_head *idtoname_table[ENT_HASHMAX];
	118
	119	static uint32_t
	120	idtoname_hash(struct ent *ent)
	121	{
	122	uint32_t hash;
	123
	124	hash = hash_str(ent->authname, ENT_HASHBITS);
	125	hash = hash_long(hash ^ ent->id, ENT_HASHBITS);
	126
	127	/* Flip LSB for user/group */
	128	if (ent->type == IDMAP_TYPE_GROUP)
	129	hash ^= 1;
	130
	131	return hash;
	132	}
	133
	134	static void
	135	idtoname_request(struct cache_detail cd, struct cache_head ch, char **bpp,
	136	int *blen)
	137	{
	138	struct ent *ent = container_of(ch, struct ent, h);
	139	char idstr[11];
	140
	141	qword_add(bpp, blen, ent->authname);
	142	snprintf(idstr, sizeof(idstr), "%d", ent->id);
	143	qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
	144	qword_add(bpp, blen, idstr);
	145
	146	(*bpp)[-1] = '\n';
	147	}
	148
f9ecc921 N	149	static int
f9ecc921 N	150	idtoname_match(struct cache_head ca, struct cache_head cb)
1da177e4	151	{
f9ecc921 N	152	struct ent *a = container_of(ca, struct ent, h);
	153	struct ent *b = container_of(cb, struct ent, h);
	154
1da177e4 LT	155	return (a->id == b->id && a->type == b->type &&
	156	strcmp(a->authname, b->authname) == 0);
	157	}
	158
	159	static int
	160	idtoname_show(struct seq_file m, struct cache_detail cd, struct cache_head *h)
	161	{
	162	struct ent *ent;
	163
	164	if (h == NULL) {
	165	seq_puts(m, "#domain type id [name]\n");
	166	return 0;
	167	}
	168	ent = container_of(h, struct ent, h);
	169	seq_printf(m, "%s %s %d", ent->authname,
	170	ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
	171	ent->id);
	172	if (test_bit(CACHE_VALID, &h->flags))
	173	seq_printf(m, " %s", ent->name);
	174	seq_printf(m, "\n");
	175	return 0;
	176	}
	177
	178	static void
	179	warn_no_idmapd(struct cache_detail *detail)
	180	{
	181	printk("nfsd: nfsv4 idmapping failing: has idmapd %s?\n",
	182	detail->last_close? "died" : "not been started");
	183	}
	184
	185
	186	static int idtoname_parse(struct cache_detail , char , int);
f9ecc921 N	187	static struct ent idtoname_lookup(struct ent );
f9ecc921 N	188	static struct ent idtoname_update(struct ent , struct ent *);
1da177e4	189
fd39ca9a	190	static struct cache_detail idtoname_cache = {
f35279d3	191	.owner = THIS_MODULE,
1da177e4 LT	192	.hash_size = ENT_HASHMAX,
	193	.hash_table = idtoname_table,
	194	.name = "nfs4.idtoname",
	195	.cache_put = ent_put,
	196	.cache_request = idtoname_request,
	197	.cache_parse = idtoname_parse,
	198	.cache_show = idtoname_show,
	199	.warn_no_listener = warn_no_idmapd,
f9ecc921 N	200	.match = idtoname_match,
	201	.init = ent_init,
	202	.update = ent_init,
	203	.alloc = ent_alloc,
1da177e4 LT	204	};
	205
	206	int
	207	idtoname_parse(struct cache_detail cd, char buf, int buflen)
	208	{
	209	struct ent ent, *res;
	210	char buf1, bp;
	211	int error = -EINVAL;
	212
	213	if (buf[buflen - 1] != '\n')
	214	return (-EINVAL);
	215	buf[buflen - 1]= '\0';
	216
	217	buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
	218	if (buf1 == NULL)
	219	return (-ENOMEM);
	220
	221	memset(&ent, 0, sizeof(ent));
	222
	223	/* Authentication name */
	224	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
	225	goto out;
	226	memcpy(ent.authname, buf1, sizeof(ent.authname));
	227
	228	/* Type */
	229	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
	230	goto out;
	231	ent.type = strcmp(buf1, "user") == 0 ?
	232	IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
	233
	234	/* ID */
	235	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
	236	goto out;
	237	ent.id = simple_strtoul(buf1, &bp, 10);
	238	if (bp == buf1)
	239	goto out;
	240
	241	/* expiry */
	242	ent.h.expiry_time = get_expiry(&buf);
	243	if (ent.h.expiry_time == 0)
	244	goto out;
	245
f9ecc921 N	246	error = -ENOMEM;
	247	res = idtoname_lookup(&ent);
	248	if (!res)
	249	goto out;
	250
1da177e4 LT	251	/* Name */
	252	error = qword_get(&buf, buf1, PAGE_SIZE);
	253	if (error == -EINVAL)
	254	goto out;
	255	if (error == -ENOENT)
	256	set_bit(CACHE_NEGATIVE, &ent.h.flags);
	257	else {
	258	if (error >= IDMAP_NAMESZ) {
	259	error = -EINVAL;
	260	goto out;
	261	}
	262	memcpy(ent.name, buf1, sizeof(ent.name));
	263	}
	264	error = -ENOMEM;
f9ecc921 N	265	res = idtoname_update(&ent, res);
f9ecc921 N	266	if (res == NULL)
1da177e4 LT	267	goto out;
1da177e4 LT	268
baab935f	269	cache_put(&res->h, &idtoname_cache);
1da177e4 LT	270
	271	error = 0;
	272	out:
	273	kfree(buf1);
	274
	275	return error;
	276	}
	277
f9ecc921 N	278
	279	static struct ent *
	280	idtoname_lookup(struct ent *item)
	281	{
	282	struct cache_head *ch = sunrpc_cache_lookup(&idtoname_cache,
	283	&item->h,
	284	idtoname_hash(item));
	285	if (ch)
	286	return container_of(ch, struct ent, h);
	287	else
	288	return NULL;
	289	}
	290
	291	static struct ent *
	292	idtoname_update(struct ent new, struct ent old)
	293	{
	294	struct cache_head *ch = sunrpc_cache_update(&idtoname_cache,
	295	&new->h, &old->h,
	296	idtoname_hash(new));
	297	if (ch)
	298	return container_of(ch, struct ent, h);
	299	else
	300	return NULL;
	301	}
	302
1da177e4 LT	303
	304	/*
	305	* Name -> ID cache
	306	*/
	307
	308	static struct cache_head *nametoid_table[ENT_HASHMAX];
	309
	310	static inline int
	311	nametoid_hash(struct ent *ent)
	312	{
	313	return hash_str(ent->name, ENT_HASHBITS);
	314	}
	315
fd39ca9a	316	static void
1da177e4 LT	317	nametoid_request(struct cache_detail cd, struct cache_head ch, char **bpp,
	318	int *blen)
	319	{
	320	struct ent *ent = container_of(ch, struct ent, h);
	321
	322	qword_add(bpp, blen, ent->authname);
	323	qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
	324	qword_add(bpp, blen, ent->name);
	325
	326	(*bpp)[-1] = '\n';
	327	}
	328
f9ecc921 N	329	static int
f9ecc921 N	330	nametoid_match(struct cache_head ca, struct cache_head cb)
1da177e4	331	{
f9ecc921 N	332	struct ent *a = container_of(ca, struct ent, h);
	333	struct ent *b = container_of(cb, struct ent, h);
	334
1da177e4 LT	335	return (a->type == b->type && strcmp(a->name, b->name) == 0 &&
	336	strcmp(a->authname, b->authname) == 0);
	337	}
	338
	339	static int
	340	nametoid_show(struct seq_file m, struct cache_detail cd, struct cache_head *h)
	341	{
	342	struct ent *ent;
	343
	344	if (h == NULL) {
	345	seq_puts(m, "#domain type name [id]\n");
	346	return 0;
	347	}
	348	ent = container_of(h, struct ent, h);
	349	seq_printf(m, "%s %s %s", ent->authname,
	350	ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
	351	ent->name);
	352	if (test_bit(CACHE_VALID, &h->flags))
	353	seq_printf(m, " %d", ent->id);
	354	seq_printf(m, "\n");
	355	return 0;
	356	}
	357
f9ecc921 N	358	static struct ent nametoid_lookup(struct ent );
f9ecc921 N	359	static struct ent nametoid_update(struct ent , struct ent *);
fd39ca9a	360	static int nametoid_parse(struct cache_detail , char , int);
1da177e4	361
fd39ca9a	362	static struct cache_detail nametoid_cache = {
f35279d3	363	.owner = THIS_MODULE,
1da177e4 LT	364	.hash_size = ENT_HASHMAX,
	365	.hash_table = nametoid_table,
	366	.name = "nfs4.nametoid",
	367	.cache_put = ent_put,
	368	.cache_request = nametoid_request,
	369	.cache_parse = nametoid_parse,
	370	.cache_show = nametoid_show,
	371	.warn_no_listener = warn_no_idmapd,
f9ecc921 N	372	.match = nametoid_match,
	373	.init = ent_init,
	374	.update = ent_init,
	375	.alloc = ent_alloc,
1da177e4 LT	376	};
1da177e4 LT	377
fd39ca9a	378	static int
1da177e4 LT	379	nametoid_parse(struct cache_detail cd, char buf, int buflen)
	380	{
	381	struct ent ent, *res;
	382	char *buf1;
	383	int error = -EINVAL;
	384
	385	if (buf[buflen - 1] != '\n')
	386	return (-EINVAL);
	387	buf[buflen - 1]= '\0';
	388
	389	buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
	390	if (buf1 == NULL)
	391	return (-ENOMEM);
	392
	393	memset(&ent, 0, sizeof(ent));
	394
	395	/* Authentication name */
	396	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
	397	goto out;
	398	memcpy(ent.authname, buf1, sizeof(ent.authname));
	399
	400	/* Type */
	401	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
	402	goto out;
	403	ent.type = strcmp(buf1, "user") == 0 ?
	404	IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
	405
	406	/* Name */
	407	error = qword_get(&buf, buf1, PAGE_SIZE);
	408	if (error <= 0 \|\| error >= IDMAP_NAMESZ)
	409	goto out;
	410	memcpy(ent.name, buf1, sizeof(ent.name));
	411
	412	/* expiry */
	413	ent.h.expiry_time = get_expiry(&buf);
	414	if (ent.h.expiry_time == 0)
	415	goto out;
	416
	417	/* ID */
	418	error = get_int(&buf, &ent.id);
	419	if (error == -EINVAL)
	420	goto out;
	421	if (error == -ENOENT)
	422	set_bit(CACHE_NEGATIVE, &ent.h.flags);
	423
	424	error = -ENOMEM;
f9ecc921 N	425	res = nametoid_lookup(&ent);
	426	if (res == NULL)
	427	goto out;
	428	res = nametoid_update(&ent, res);
	429	if (res == NULL)
1da177e4 LT	430	goto out;
1da177e4 LT	431
baab935f	432	cache_put(&res->h, &nametoid_cache);
1da177e4 LT	433	error = 0;
	434	out:
	435	kfree(buf1);
	436
	437	return (error);
	438	}
	439
f9ecc921 N	440
	441	static struct ent *
	442	nametoid_lookup(struct ent *item)
	443	{
	444	struct cache_head *ch = sunrpc_cache_lookup(&nametoid_cache,
	445	&item->h,
	446	nametoid_hash(item));
	447	if (ch)
	448	return container_of(ch, struct ent, h);
	449	else
	450	return NULL;
	451	}
	452
	453	static struct ent *
	454	nametoid_update(struct ent new, struct ent old)
	455	{
	456	struct cache_head *ch = sunrpc_cache_update(&nametoid_cache,
	457	&new->h, &old->h,
	458	nametoid_hash(new));
	459	if (ch)
	460	return container_of(ch, struct ent, h);
	461	else
	462	return NULL;
	463	}
1da177e4 LT	464
	465	/*
	466	* Exported API
	467	*/
	468
	469	void
	470	nfsd_idmap_init(void)
	471	{
	472	cache_register(&idtoname_cache);
	473	cache_register(&nametoid_cache);
	474	}
	475
	476	void
	477	nfsd_idmap_shutdown(void)
	478	{
f35279d3 BA	479	if (cache_unregister(&idtoname_cache))
	480	printk(KERN_ERR "nfsd: failed to unregister idtoname cache\n");
	481	if (cache_unregister(&nametoid_cache))
	482	printk(KERN_ERR "nfsd: failed to unregister nametoid cache\n");
1da177e4 LT	483	}
	484
	485	/*
	486	* Deferred request handling
	487	*/
	488
	489	struct idmap_defer_req {
	490	struct cache_req req;
	491	struct cache_deferred_req deferred_req;
	492	wait_queue_head_t waitq;
	493	atomic_t count;
	494	};
	495
	496	static inline void
	497	put_mdr(struct idmap_defer_req *mdr)
	498	{
	499	if (atomic_dec_and_test(&mdr->count))
	500	kfree(mdr);
	501	}
	502
	503	static inline void
	504	get_mdr(struct idmap_defer_req *mdr)
	505	{
	506	atomic_inc(&mdr->count);
	507	}
	508
	509	static void
	510	idmap_revisit(struct cache_deferred_req *dreq, int toomany)
	511	{
	512	struct idmap_defer_req *mdr =
	513	container_of(dreq, struct idmap_defer_req, deferred_req);
	514
	515	wake_up(&mdr->waitq);
	516	put_mdr(mdr);
	517	}
	518
	519	static struct cache_deferred_req *
	520	idmap_defer(struct cache_req *req)
	521	{
	522	struct idmap_defer_req *mdr =
	523	container_of(req, struct idmap_defer_req, req);
	524
	525	mdr->deferred_req.revisit = idmap_revisit;
	526	get_mdr(mdr);
	527	return (&mdr->deferred_req);
	528	}
	529
	530	static inline int
f9ecc921	531	do_idmap_lookup(struct ent (lookup_fn)(struct ent ), struct ent key,
1da177e4 LT	532	struct cache_detail detail, struct ent *item,
	533	struct idmap_defer_req *mdr)
	534	{
f9ecc921	535	*item = lookup_fn(key);
1da177e4 LT	536	if (!*item)
	537	return -ENOMEM;
	538	return cache_check(detail, &(*item)->h, &mdr->req);
	539	}
	540
	541	static inline int
f9ecc921	542	do_idmap_lookup_nowait(struct ent (lookup_fn)(struct ent *),
1da177e4 LT	543	struct ent key, struct cache_detail detail,
	544	struct ent **item)
	545	{
	546	int ret = -ENOMEM;
	547
f9ecc921	548	*item = lookup_fn(key);
1da177e4 LT	549	if (!*item)
	550	goto out_err;
	551	ret = -ETIMEDOUT;
	552	if (!test_bit(CACHE_VALID, &(*item)->h.flags)
	553	\|\| (*item)->h.expiry_time < get_seconds()
	554	\|\| detail->flush_time > (*item)->h.last_refresh)
	555	goto out_put;
	556	ret = -ENOENT;
	557	if (test_bit(CACHE_NEGATIVE, &(*item)->h.flags))
	558	goto out_put;
	559	return 0;
	560	out_put:
baab935f	561	cache_put(&(*item)->h, detail);
1da177e4 LT	562	out_err:
	563	*item = NULL;
	564	return ret;
	565	}
	566
	567	static int
	568	idmap_lookup(struct svc_rqst *rqstp,
f9ecc921	569	struct ent (lookup_fn)(struct ent ), struct ent key,
1da177e4 LT	570	struct cache_detail detail, struct ent *item)
	571	{
	572	struct idmap_defer_req *mdr;
	573	int ret;
	574
f8314dc6	575	mdr = kzalloc(sizeof(*mdr), GFP_KERNEL);
1da177e4 LT	576	if (!mdr)
1da177e4 LT	577	return -ENOMEM;
1da177e4 LT	578	atomic_set(&mdr->count, 1);
	579	init_waitqueue_head(&mdr->waitq);
	580	mdr->req.defer = idmap_defer;
	581	ret = do_idmap_lookup(lookup_fn, key, detail, item, mdr);
	582	if (ret == -EAGAIN) {
	583	wait_event_interruptible_timeout(mdr->waitq,
	584	test_bit(CACHE_VALID, &(item)->h.flags), 1 HZ);
	585	ret = do_idmap_lookup_nowait(lookup_fn, key, detail, item);
	586	}
	587	put_mdr(mdr);
	588	return ret;
	589	}
	590
	591	static int
	592	idmap_name_to_id(struct svc_rqst rqstp, int type, const char name, u32 namelen,
	593	uid_t *id)
	594	{
	595	struct ent *item, key = {
	596	.type = type,
	597	};
	598	int ret;
	599
	600	if (namelen + 1 > sizeof(key.name))
	601	return -EINVAL;
	602	memcpy(key.name, name, namelen);
	603	key.name[namelen] = '\0';
	604	strlcpy(key.authname, rqstp->rq_client->name, sizeof(key.authname));
	605	ret = idmap_lookup(rqstp, nametoid_lookup, &key, &nametoid_cache, &item);
	606	if (ret == -ENOENT)
	607	ret = -ESRCH; /* nfserr_badname */
	608	if (ret)
	609	return ret;
	610	*id = item->id;
baab935f	611	cache_put(&item->h, &nametoid_cache);
1da177e4 LT	612	return 0;
	613	}
	614
	615	static int
	616	idmap_id_to_name(struct svc_rqst rqstp, int type, uid_t id, char name)
	617	{
	618	struct ent *item, key = {
	619	.id = id,
	620	.type = type,
	621	};
	622	int ret;
	623
	624	strlcpy(key.authname, rqstp->rq_client->name, sizeof(key.authname));
	625	ret = idmap_lookup(rqstp, idtoname_lookup, &key, &idtoname_cache, &item);
	626	if (ret == -ENOENT)
	627	return sprintf(name, "%u", id);
	628	if (ret)
	629	return ret;
	630	ret = strlen(item->name);
	631	BUG_ON(ret > IDMAP_NAMESZ);
	632	memcpy(name, item->name, ret);
baab935f	633	cache_put(&item->h, &idtoname_cache);
1da177e4 LT	634	return ret;
	635	}
	636
	637	int
	638	nfsd_map_name_to_uid(struct svc_rqst rqstp, const char name, size_t namelen,
	639	__u32 *id)
	640	{
	641	return idmap_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, id);
	642	}
	643
	644	int
	645	nfsd_map_name_to_gid(struct svc_rqst rqstp, const char name, size_t namelen,
	646	__u32 *id)
	647	{
	648	return idmap_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, id);
	649	}
	650
	651	int
	652	nfsd_map_uid_to_name(struct svc_rqst rqstp, __u32 id, char name)
	653	{
	654	return idmap_id_to_name(rqstp, IDMAP_TYPE_USER, id, name);
	655	}
	656
	657	int
	658	nfsd_map_gid_to_name(struct svc_rqst rqstp, __u32 id, char name)
	659	{
	660	return idmap_id_to_name(rqstp, IDMAP_TYPE_GROUP, id, name);
	661	}