[linux.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 <[email protected]>
 *
 *  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/sched.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 <[email protected]>
	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>
	53	#include <linux/sched.h>
	54	#include <linux/time.h>
	55	#include <linux/seq_file.h>
	56	#include <linux/sunrpc/svcauth.h>
	57
	58	/*
	59	* Cache entry
	60	*/
	61
	62	/*
	63	* XXX we know that IDMAP_NAMESZ < PAGE_SIZE, but it's ugly to rely on
	64	* that.
	65	*/
	66
	67	#define IDMAP_TYPE_USER 0
	68	#define IDMAP_TYPE_GROUP 1
	69
	70	struct ent {
	71	struct cache_head h;
	72	int type; /* User / Group */
	73	uid_t id;
	74	char name[IDMAP_NAMESZ];
	75	char authname[IDMAP_NAMESZ];
	76	};
	77
1da177e4 LT	78	/* Common entry handling */
	79
	80	#define ENT_HASHBITS 8
	81	#define ENT_HASHMAX (1 << ENT_HASHBITS)
	82	#define ENT_HASHMASK (ENT_HASHMAX - 1)
	83
f9ecc921 N	84	static void
f9ecc921 N	85	ent_init(struct cache_head cnew, struct cache_head citm)
1da177e4	86	{
f9ecc921 N	87	struct ent *new = container_of(cnew, struct ent, h);
	88	struct ent *itm = container_of(citm, struct ent, h);
	89
1da177e4 LT	90	new->id = itm->id;
	91	new->type = itm->type;
	92
	93	strlcpy(new->name, itm->name, sizeof(new->name));
	94	strlcpy(new->authname, itm->authname, sizeof(new->name));
	95	}
	96
fd39ca9a	97	static void
baab935f	98	ent_put(struct kref *ref)
1da177e4	99	{
baab935f N	100	struct ent *map = container_of(ref, struct ent, h.ref);
baab935f N	101	kfree(map);
1da177e4 LT	102	}
1da177e4 LT	103
f9ecc921 N	104	static struct cache_head *
	105	ent_alloc(void)
	106	{
	107	struct ent e = kmalloc(sizeof(e), GFP_KERNEL);
	108	if (e)
	109	return &e->h;
	110	else
	111	return NULL;
	112	}
	113
1da177e4 LT	114	/*
	115	* ID -> Name cache
	116	*/
	117
	118	static struct cache_head *idtoname_table[ENT_HASHMAX];
	119
	120	static uint32_t
	121	idtoname_hash(struct ent *ent)
	122	{
	123	uint32_t hash;
	124
	125	hash = hash_str(ent->authname, ENT_HASHBITS);
	126	hash = hash_long(hash ^ ent->id, ENT_HASHBITS);
	127
	128	/* Flip LSB for user/group */
	129	if (ent->type == IDMAP_TYPE_GROUP)
	130	hash ^= 1;
	131
	132	return hash;
	133	}
	134
	135	static void
	136	idtoname_request(struct cache_detail cd, struct cache_head ch, char **bpp,
	137	int *blen)
	138	{
	139	struct ent *ent = container_of(ch, struct ent, h);
	140	char idstr[11];
	141
	142	qword_add(bpp, blen, ent->authname);
	143	snprintf(idstr, sizeof(idstr), "%d", ent->id);
	144	qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
	145	qword_add(bpp, blen, idstr);
	146
	147	(*bpp)[-1] = '\n';
	148	}
	149
f9ecc921 N	150	static int
f9ecc921 N	151	idtoname_match(struct cache_head ca, struct cache_head cb)
1da177e4	152	{
f9ecc921 N	153	struct ent *a = container_of(ca, struct ent, h);
	154	struct ent *b = container_of(cb, struct ent, h);
	155
1da177e4 LT	156	return (a->id == b->id && a->type == b->type &&
	157	strcmp(a->authname, b->authname) == 0);
	158	}
	159
	160	static int
	161	idtoname_show(struct seq_file m, struct cache_detail cd, struct cache_head *h)
	162	{
	163	struct ent *ent;
	164
	165	if (h == NULL) {
	166	seq_puts(m, "#domain type id [name]\n");
	167	return 0;
	168	}
	169	ent = container_of(h, struct ent, h);
	170	seq_printf(m, "%s %s %d", ent->authname,
	171	ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
	172	ent->id);
	173	if (test_bit(CACHE_VALID, &h->flags))
	174	seq_printf(m, " %s", ent->name);
	175	seq_printf(m, "\n");
	176	return 0;
	177	}
	178
	179	static void
	180	warn_no_idmapd(struct cache_detail *detail)
	181	{
	182	printk("nfsd: nfsv4 idmapping failing: has idmapd %s?\n",
	183	detail->last_close? "died" : "not been started");
	184	}
	185
	186
	187	static int idtoname_parse(struct cache_detail , char , int);
f9ecc921 N	188	static struct ent idtoname_lookup(struct ent );
f9ecc921 N	189	static struct ent idtoname_update(struct ent , struct ent *);
1da177e4	190
fd39ca9a	191	static struct cache_detail idtoname_cache = {
f35279d3	192	.owner = THIS_MODULE,
1da177e4 LT	193	.hash_size = ENT_HASHMAX,
	194	.hash_table = idtoname_table,
	195	.name = "nfs4.idtoname",
	196	.cache_put = ent_put,
	197	.cache_request = idtoname_request,
	198	.cache_parse = idtoname_parse,
	199	.cache_show = idtoname_show,
	200	.warn_no_listener = warn_no_idmapd,
f9ecc921 N	201	.match = idtoname_match,
	202	.init = ent_init,
	203	.update = ent_init,
	204	.alloc = ent_alloc,
1da177e4 LT	205	};
	206
	207	int
	208	idtoname_parse(struct cache_detail cd, char buf, int buflen)
	209	{
	210	struct ent ent, *res;
	211	char buf1, bp;
	212	int error = -EINVAL;
	213
	214	if (buf[buflen - 1] != '\n')
	215	return (-EINVAL);
	216	buf[buflen - 1]= '\0';
	217
	218	buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
	219	if (buf1 == NULL)
	220	return (-ENOMEM);
	221
	222	memset(&ent, 0, sizeof(ent));
	223
	224	/* Authentication name */
	225	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
	226	goto out;
	227	memcpy(ent.authname, buf1, sizeof(ent.authname));
	228
	229	/* Type */
	230	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
	231	goto out;
	232	ent.type = strcmp(buf1, "user") == 0 ?
	233	IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
	234
	235	/* ID */
	236	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
	237	goto out;
	238	ent.id = simple_strtoul(buf1, &bp, 10);
	239	if (bp == buf1)
	240	goto out;
	241
	242	/* expiry */
	243	ent.h.expiry_time = get_expiry(&buf);
	244	if (ent.h.expiry_time == 0)
	245	goto out;
	246
f9ecc921 N	247	error = -ENOMEM;
	248	res = idtoname_lookup(&ent);
	249	if (!res)
	250	goto out;
	251
1da177e4 LT	252	/* Name */
	253	error = qword_get(&buf, buf1, PAGE_SIZE);
	254	if (error == -EINVAL)
	255	goto out;
	256	if (error == -ENOENT)
	257	set_bit(CACHE_NEGATIVE, &ent.h.flags);
	258	else {
	259	if (error >= IDMAP_NAMESZ) {
	260	error = -EINVAL;
	261	goto out;
	262	}
	263	memcpy(ent.name, buf1, sizeof(ent.name));
	264	}
	265	error = -ENOMEM;
f9ecc921 N	266	res = idtoname_update(&ent, res);
f9ecc921 N	267	if (res == NULL)
1da177e4 LT	268	goto out;
1da177e4 LT	269
baab935f	270	cache_put(&res->h, &idtoname_cache);
1da177e4 LT	271
	272	error = 0;
	273	out:
	274	kfree(buf1);
	275
	276	return error;
	277	}
	278
f9ecc921 N	279
	280	static struct ent *
	281	idtoname_lookup(struct ent *item)
	282	{
	283	struct cache_head *ch = sunrpc_cache_lookup(&idtoname_cache,
	284	&item->h,
	285	idtoname_hash(item));
	286	if (ch)
	287	return container_of(ch, struct ent, h);
	288	else
	289	return NULL;
	290	}
	291
	292	static struct ent *
	293	idtoname_update(struct ent new, struct ent old)
	294	{
	295	struct cache_head *ch = sunrpc_cache_update(&idtoname_cache,
	296	&new->h, &old->h,
	297	idtoname_hash(new));
	298	if (ch)
	299	return container_of(ch, struct ent, h);
	300	else
	301	return NULL;
	302	}
	303
1da177e4 LT	304
	305	/*
	306	* Name -> ID cache
	307	*/
	308
	309	static struct cache_head *nametoid_table[ENT_HASHMAX];
	310
	311	static inline int
	312	nametoid_hash(struct ent *ent)
	313	{
	314	return hash_str(ent->name, ENT_HASHBITS);
	315	}
	316
fd39ca9a	317	static void
1da177e4 LT	318	nametoid_request(struct cache_detail cd, struct cache_head ch, char **bpp,
	319	int *blen)
	320	{
	321	struct ent *ent = container_of(ch, struct ent, h);
	322
	323	qword_add(bpp, blen, ent->authname);
	324	qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
	325	qword_add(bpp, blen, ent->name);
	326
	327	(*bpp)[-1] = '\n';
	328	}
	329
f9ecc921 N	330	static int
f9ecc921 N	331	nametoid_match(struct cache_head ca, struct cache_head cb)
1da177e4	332	{
f9ecc921 N	333	struct ent *a = container_of(ca, struct ent, h);
	334	struct ent *b = container_of(cb, struct ent, h);
	335
1da177e4 LT	336	return (a->type == b->type && strcmp(a->name, b->name) == 0 &&
	337	strcmp(a->authname, b->authname) == 0);
	338	}
	339
	340	static int
	341	nametoid_show(struct seq_file m, struct cache_detail cd, struct cache_head *h)
	342	{
	343	struct ent *ent;
	344
	345	if (h == NULL) {
	346	seq_puts(m, "#domain type name [id]\n");
	347	return 0;
	348	}
	349	ent = container_of(h, struct ent, h);
	350	seq_printf(m, "%s %s %s", ent->authname,
	351	ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
	352	ent->name);
	353	if (test_bit(CACHE_VALID, &h->flags))
	354	seq_printf(m, " %d", ent->id);
	355	seq_printf(m, "\n");
	356	return 0;
	357	}
	358
f9ecc921 N	359	static struct ent nametoid_lookup(struct ent );
f9ecc921 N	360	static struct ent nametoid_update(struct ent , struct ent *);
fd39ca9a	361	static int nametoid_parse(struct cache_detail , char , int);
1da177e4	362
fd39ca9a	363	static struct cache_detail nametoid_cache = {
f35279d3	364	.owner = THIS_MODULE,
1da177e4 LT	365	.hash_size = ENT_HASHMAX,
	366	.hash_table = nametoid_table,
	367	.name = "nfs4.nametoid",
	368	.cache_put = ent_put,
	369	.cache_request = nametoid_request,
	370	.cache_parse = nametoid_parse,
	371	.cache_show = nametoid_show,
	372	.warn_no_listener = warn_no_idmapd,
f9ecc921 N	373	.match = nametoid_match,
	374	.init = ent_init,
	375	.update = ent_init,
	376	.alloc = ent_alloc,
1da177e4 LT	377	};
1da177e4 LT	378
fd39ca9a	379	static int
1da177e4 LT	380	nametoid_parse(struct cache_detail cd, char buf, int buflen)
	381	{
	382	struct ent ent, *res;
	383	char *buf1;
	384	int error = -EINVAL;
	385
	386	if (buf[buflen - 1] != '\n')
	387	return (-EINVAL);
	388	buf[buflen - 1]= '\0';
	389
	390	buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
	391	if (buf1 == NULL)
	392	return (-ENOMEM);
	393
	394	memset(&ent, 0, sizeof(ent));
	395
	396	/* Authentication name */
	397	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
	398	goto out;
	399	memcpy(ent.authname, buf1, sizeof(ent.authname));
	400
	401	/* Type */
	402	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
	403	goto out;
	404	ent.type = strcmp(buf1, "user") == 0 ?
	405	IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
	406
	407	/* Name */
	408	error = qword_get(&buf, buf1, PAGE_SIZE);
	409	if (error <= 0 \|\| error >= IDMAP_NAMESZ)
	410	goto out;
	411	memcpy(ent.name, buf1, sizeof(ent.name));
	412
	413	/* expiry */
	414	ent.h.expiry_time = get_expiry(&buf);
	415	if (ent.h.expiry_time == 0)
	416	goto out;
	417
	418	/* ID */
	419	error = get_int(&buf, &ent.id);
	420	if (error == -EINVAL)
	421	goto out;
	422	if (error == -ENOENT)
	423	set_bit(CACHE_NEGATIVE, &ent.h.flags);
	424
	425	error = -ENOMEM;
f9ecc921 N	426	res = nametoid_lookup(&ent);
	427	if (res == NULL)
	428	goto out;
	429	res = nametoid_update(&ent, res);
	430	if (res == NULL)
1da177e4 LT	431	goto out;
1da177e4 LT	432
baab935f	433	cache_put(&res->h, &nametoid_cache);
1da177e4 LT	434	error = 0;
	435	out:
	436	kfree(buf1);
	437
	438	return (error);
	439	}
	440
f9ecc921 N	441
	442	static struct ent *
	443	nametoid_lookup(struct ent *item)
	444	{
	445	struct cache_head *ch = sunrpc_cache_lookup(&nametoid_cache,
	446	&item->h,
	447	nametoid_hash(item));
	448	if (ch)
	449	return container_of(ch, struct ent, h);
	450	else
	451	return NULL;
	452	}
	453
	454	static struct ent *
	455	nametoid_update(struct ent new, struct ent old)
	456	{
	457	struct cache_head *ch = sunrpc_cache_update(&nametoid_cache,
	458	&new->h, &old->h,
	459	nametoid_hash(new));
	460	if (ch)
	461	return container_of(ch, struct ent, h);
	462	else
	463	return NULL;
	464	}
1da177e4 LT	465
	466	/*
	467	* Exported API
	468	*/
	469
	470	void
	471	nfsd_idmap_init(void)
	472	{
	473	cache_register(&idtoname_cache);
	474	cache_register(&nametoid_cache);
	475	}
	476
	477	void
	478	nfsd_idmap_shutdown(void)
	479	{
f35279d3 BA	480	if (cache_unregister(&idtoname_cache))
	481	printk(KERN_ERR "nfsd: failed to unregister idtoname cache\n");
	482	if (cache_unregister(&nametoid_cache))
	483	printk(KERN_ERR "nfsd: failed to unregister nametoid cache\n");
1da177e4 LT	484	}
	485
	486	/*
	487	* Deferred request handling
	488	*/
	489
	490	struct idmap_defer_req {
	491	struct cache_req req;
	492	struct cache_deferred_req deferred_req;
	493	wait_queue_head_t waitq;
	494	atomic_t count;
	495	};
	496
	497	static inline void
	498	put_mdr(struct idmap_defer_req *mdr)
	499	{
	500	if (atomic_dec_and_test(&mdr->count))
	501	kfree(mdr);
	502	}
	503
	504	static inline void
	505	get_mdr(struct idmap_defer_req *mdr)
	506	{
	507	atomic_inc(&mdr->count);
	508	}
	509
	510	static void
	511	idmap_revisit(struct cache_deferred_req *dreq, int toomany)
	512	{
	513	struct idmap_defer_req *mdr =
	514	container_of(dreq, struct idmap_defer_req, deferred_req);
	515
	516	wake_up(&mdr->waitq);
	517	put_mdr(mdr);
	518	}
	519
	520	static struct cache_deferred_req *
	521	idmap_defer(struct cache_req *req)
	522	{
	523	struct idmap_defer_req *mdr =
	524	container_of(req, struct idmap_defer_req, req);
	525
	526	mdr->deferred_req.revisit = idmap_revisit;
	527	get_mdr(mdr);
	528	return (&mdr->deferred_req);
	529	}
	530
	531	static inline int
f9ecc921	532	do_idmap_lookup(struct ent (lookup_fn)(struct ent ), struct ent key,
1da177e4 LT	533	struct cache_detail detail, struct ent *item,
	534	struct idmap_defer_req *mdr)
	535	{
f9ecc921	536	*item = lookup_fn(key);
1da177e4 LT	537	if (!*item)
	538	return -ENOMEM;
	539	return cache_check(detail, &(*item)->h, &mdr->req);
	540	}
	541
	542	static inline int
f9ecc921	543	do_idmap_lookup_nowait(struct ent (lookup_fn)(struct ent *),
1da177e4 LT	544	struct ent key, struct cache_detail detail,
	545	struct ent **item)
	546	{
	547	int ret = -ENOMEM;
	548
f9ecc921	549	*item = lookup_fn(key);
1da177e4 LT	550	if (!*item)
	551	goto out_err;
	552	ret = -ETIMEDOUT;
	553	if (!test_bit(CACHE_VALID, &(*item)->h.flags)
	554	\|\| (*item)->h.expiry_time < get_seconds()
	555	\|\| detail->flush_time > (*item)->h.last_refresh)
	556	goto out_put;
	557	ret = -ENOENT;
	558	if (test_bit(CACHE_NEGATIVE, &(*item)->h.flags))
	559	goto out_put;
	560	return 0;
	561	out_put:
baab935f	562	cache_put(&(*item)->h, detail);
1da177e4 LT	563	out_err:
	564	*item = NULL;
	565	return ret;
	566	}
	567
	568	static int
	569	idmap_lookup(struct svc_rqst *rqstp,
f9ecc921	570	struct ent (lookup_fn)(struct ent ), struct ent key,
1da177e4 LT	571	struct cache_detail detail, struct ent *item)
	572	{
	573	struct idmap_defer_req *mdr;
	574	int ret;
	575
f8314dc6	576	mdr = kzalloc(sizeof(*mdr), GFP_KERNEL);
1da177e4 LT	577	if (!mdr)
1da177e4 LT	578	return -ENOMEM;
1da177e4 LT	579	atomic_set(&mdr->count, 1);
	580	init_waitqueue_head(&mdr->waitq);
	581	mdr->req.defer = idmap_defer;
	582	ret = do_idmap_lookup(lookup_fn, key, detail, item, mdr);
	583	if (ret == -EAGAIN) {
	584	wait_event_interruptible_timeout(mdr->waitq,
	585	test_bit(CACHE_VALID, &(item)->h.flags), 1 HZ);
	586	ret = do_idmap_lookup_nowait(lookup_fn, key, detail, item);
	587	}
	588	put_mdr(mdr);
	589	return ret;
	590	}
	591
	592	static int
	593	idmap_name_to_id(struct svc_rqst rqstp, int type, const char name, u32 namelen,
	594	uid_t *id)
	595	{
	596	struct ent *item, key = {
	597	.type = type,
	598	};
	599	int ret;
	600
	601	if (namelen + 1 > sizeof(key.name))
	602	return -EINVAL;
	603	memcpy(key.name, name, namelen);
	604	key.name[namelen] = '\0';
	605	strlcpy(key.authname, rqstp->rq_client->name, sizeof(key.authname));
	606	ret = idmap_lookup(rqstp, nametoid_lookup, &key, &nametoid_cache, &item);
	607	if (ret == -ENOENT)
	608	ret = -ESRCH; /* nfserr_badname */
	609	if (ret)
	610	return ret;
	611	*id = item->id;
baab935f	612	cache_put(&item->h, &nametoid_cache);
1da177e4 LT	613	return 0;
	614	}
	615
	616	static int
	617	idmap_id_to_name(struct svc_rqst rqstp, int type, uid_t id, char name)
	618	{
	619	struct ent *item, key = {
	620	.id = id,
	621	.type = type,
	622	};
	623	int ret;
	624
	625	strlcpy(key.authname, rqstp->rq_client->name, sizeof(key.authname));
	626	ret = idmap_lookup(rqstp, idtoname_lookup, &key, &idtoname_cache, &item);
	627	if (ret == -ENOENT)
	628	return sprintf(name, "%u", id);
	629	if (ret)
	630	return ret;
	631	ret = strlen(item->name);
	632	BUG_ON(ret > IDMAP_NAMESZ);
	633	memcpy(name, item->name, ret);
baab935f	634	cache_put(&item->h, &idtoname_cache);
1da177e4 LT	635	return ret;
	636	}
	637
	638	int
	639	nfsd_map_name_to_uid(struct svc_rqst rqstp, const char name, size_t namelen,
	640	__u32 *id)
	641	{
	642	return idmap_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, id);
	643	}
	644
	645	int
	646	nfsd_map_name_to_gid(struct svc_rqst rqstp, const char name, size_t namelen,
	647	__u32 *id)
	648	{
	649	return idmap_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, id);
	650	}
	651
	652	int
	653	nfsd_map_uid_to_name(struct svc_rqst rqstp, __u32 id, char name)
	654	{
	655	return idmap_id_to_name(rqstp, IDMAP_TYPE_USER, id, name);
	656	}
	657
	658	int
	659	nfsd_map_gid_to_name(struct svc_rqst rqstp, __u32 id, char name)
	660	{
	661	return idmap_id_to_name(rqstp, IDMAP_TYPE_GROUP, id, name);
	662	}