[deliverable/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 <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/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/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), "%u", ent->id);
	qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
	qword_add(bpp, blen, idstr);

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

static int
idtoname_upcall(struct cache_detail *cd, struct cache_head *ch)
{
	return sunrpc_cache_pipe_upcall(cd, ch, idtoname_request);
}

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 %u", 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, int has_died)
{
	printk("nfsd: nfsv4 idmapping failing: has idmapd %s?\n",
			has_died ? "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_upcall	= idtoname_upcall,
	.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,
};

static int
idtoname_parse(struct cache_detail *cd, char *buf, int buflen)
{
	struct ent ent, *res;
	char *buf1, *bp;
	int len;
	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 = -EINVAL;
	len = qword_get(&buf, buf1, PAGE_SIZE);
	if (len < 0)
		goto out;
	if (len == 0)
		set_bit(CACHE_NEGATIVE, &ent.h.flags);
	else if (len >= IDMAP_NAMESZ)
		goto out;
	else
		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_upcall(struct cache_detail *cd, struct cache_head *ch)
{
	return sunrpc_cache_pipe_upcall(cd, ch, nametoid_request);
}

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, " %u", 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_upcall	= nametoid_upcall,
	.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
 */

int
nfsd_idmap_init(void)
{
	int rv;

	rv = cache_register(&idtoname_cache);
	if (rv)
		return rv;
	rv = cache_register(&nametoid_cache);
	if (rv)
		cache_unregister(&idtoname_cache);
	return rv;
}

void
nfsd_idmap_shutdown(void)
{
	cache_unregister(&idtoname_cache);
	cache_unregister(&nametoid_cache);
}

/*
 * 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 char *
rqst_authname(struct svc_rqst *rqstp)
{
	struct auth_domain *clp;

	clp = rqstp->rq_gssclient ? rqstp->rq_gssclient : rqstp->rq_client;
	return clp->name;
}

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, rqst_authname(rqstp), 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, rqst_authname(rqstp), 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>
1da177e4 LT	41	#include <linux/errno.h>
	42	#include <linux/string.h>
	43	#include <linux/sunrpc/clnt.h>
	44	#include <linux/nfs.h>
	45	#include <linux/nfs4.h>
	46	#include <linux/nfs_fs.h>
	47	#include <linux/nfs_page.h>
1da177e4 LT	48	#include <linux/sunrpc/cache.h>
	49	#include <linux/nfsd_idmap.h>
	50	#include <linux/list.h>
1da177e4 LT	51	#include <linux/time.h>
	52	#include <linux/seq_file.h>
	53	#include <linux/sunrpc/svcauth.h>
	54
	55	/*
	56	* Cache entry
	57	*/
	58
	59	/*
	60	* XXX we know that IDMAP_NAMESZ < PAGE_SIZE, but it's ugly to rely on
	61	* that.
	62	*/
	63
	64	#define IDMAP_TYPE_USER 0
	65	#define IDMAP_TYPE_GROUP 1
	66
	67	struct ent {
	68	struct cache_head h;
	69	int type; /* User / Group */
	70	uid_t id;
	71	char name[IDMAP_NAMESZ];
	72	char authname[IDMAP_NAMESZ];
	73	};
	74
1da177e4 LT	75	/* Common entry handling */
	76
	77	#define ENT_HASHBITS 8
	78	#define ENT_HASHMAX (1 << ENT_HASHBITS)
	79	#define ENT_HASHMASK (ENT_HASHMAX - 1)
	80
f9ecc921 N	81	static void
f9ecc921 N	82	ent_init(struct cache_head cnew, struct cache_head citm)
1da177e4	83	{
f9ecc921 N	84	struct ent *new = container_of(cnew, struct ent, h);
	85	struct ent *itm = container_of(citm, struct ent, h);
	86
1da177e4 LT	87	new->id = itm->id;
	88	new->type = itm->type;
	89
	90	strlcpy(new->name, itm->name, sizeof(new->name));
	91	strlcpy(new->authname, itm->authname, sizeof(new->name));
	92	}
	93
fd39ca9a	94	static void
baab935f	95	ent_put(struct kref *ref)
1da177e4	96	{
baab935f N	97	struct ent *map = container_of(ref, struct ent, h.ref);
baab935f N	98	kfree(map);
1da177e4 LT	99	}
1da177e4 LT	100
f9ecc921 N	101	static struct cache_head *
	102	ent_alloc(void)
	103	{
	104	struct ent e = kmalloc(sizeof(e), GFP_KERNEL);
	105	if (e)
	106	return &e->h;
	107	else
	108	return NULL;
	109	}
	110
1da177e4 LT	111	/*
	112	* ID -> Name cache
	113	*/
	114
	115	static struct cache_head *idtoname_table[ENT_HASHMAX];
	116
	117	static uint32_t
	118	idtoname_hash(struct ent *ent)
	119	{
	120	uint32_t hash;
	121
	122	hash = hash_str(ent->authname, ENT_HASHBITS);
	123	hash = hash_long(hash ^ ent->id, ENT_HASHBITS);
	124
	125	/* Flip LSB for user/group */
	126	if (ent->type == IDMAP_TYPE_GROUP)
	127	hash ^= 1;
	128
	129	return hash;
	130	}
	131
	132	static void
	133	idtoname_request(struct cache_detail cd, struct cache_head ch, char **bpp,
	134	int *blen)
	135	{
	136	struct ent *ent = container_of(ch, struct ent, h);
	137	char idstr[11];
	138
	139	qword_add(bpp, blen, ent->authname);
0a725fc4	140	snprintf(idstr, sizeof(idstr), "%u", ent->id);
1da177e4 LT	141	qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
	142	qword_add(bpp, blen, idstr);
	143
	144	(*bpp)[-1] = '\n';
	145	}
	146
bc74b4f5 TM	147	static int
	148	idtoname_upcall(struct cache_detail cd, struct cache_head ch)
	149	{
	150	return sunrpc_cache_pipe_upcall(cd, ch, idtoname_request);
	151	}
	152
f9ecc921 N	153	static int
f9ecc921 N	154	idtoname_match(struct cache_head ca, struct cache_head cb)
1da177e4	155	{
f9ecc921 N	156	struct ent *a = container_of(ca, struct ent, h);
	157	struct ent *b = container_of(cb, struct ent, h);
	158
1da177e4 LT	159	return (a->id == b->id && a->type == b->type &&
	160	strcmp(a->authname, b->authname) == 0);
	161	}
	162
	163	static int
	164	idtoname_show(struct seq_file m, struct cache_detail cd, struct cache_head *h)
	165	{
	166	struct ent *ent;
	167
	168	if (h == NULL) {
	169	seq_puts(m, "#domain type id [name]\n");
	170	return 0;
	171	}
	172	ent = container_of(h, struct ent, h);
0a725fc4	173	seq_printf(m, "%s %s %u", ent->authname,
1da177e4 LT	174	ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
	175	ent->id);
	176	if (test_bit(CACHE_VALID, &h->flags))
	177	seq_printf(m, " %s", ent->name);
	178	seq_printf(m, "\n");
	179	return 0;
	180	}
	181
	182	static void
2da8ca26	183	warn_no_idmapd(struct cache_detail *detail, int has_died)
1da177e4 LT	184	{
1da177e4 LT	185	printk("nfsd: nfsv4 idmapping failing: has idmapd %s?\n",
2da8ca26	186	has_died ? "died" : "not been started");
1da177e4 LT	187	}
	188
	189
	190	static int idtoname_parse(struct cache_detail , char , int);
f9ecc921 N	191	static struct ent idtoname_lookup(struct ent );
f9ecc921 N	192	static struct ent idtoname_update(struct ent , struct ent *);
1da177e4	193
fd39ca9a	194	static struct cache_detail idtoname_cache = {
f35279d3	195	.owner = THIS_MODULE,
1da177e4 LT	196	.hash_size = ENT_HASHMAX,
	197	.hash_table = idtoname_table,
	198	.name = "nfs4.idtoname",
	199	.cache_put = ent_put,
bc74b4f5	200	.cache_upcall = idtoname_upcall,
1da177e4 LT	201	.cache_parse = idtoname_parse,
	202	.cache_show = idtoname_show,
	203	.warn_no_listener = warn_no_idmapd,
f9ecc921 N	204	.match = idtoname_match,
	205	.init = ent_init,
	206	.update = ent_init,
	207	.alloc = ent_alloc,
1da177e4 LT	208	};
1da177e4 LT	209
a254b246	210	static int
1da177e4 LT	211	idtoname_parse(struct cache_detail cd, char buf, int buflen)
	212	{
	213	struct ent ent, *res;
	214	char buf1, bp;
c9b6cbe5	215	int len;
1da177e4 LT	216	int error = -EINVAL;
	217
	218	if (buf[buflen - 1] != '\n')
	219	return (-EINVAL);
	220	buf[buflen - 1]= '\0';
	221
	222	buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
	223	if (buf1 == NULL)
	224	return (-ENOMEM);
	225
	226	memset(&ent, 0, sizeof(ent));
	227
	228	/* Authentication name */
	229	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
	230	goto out;
	231	memcpy(ent.authname, buf1, sizeof(ent.authname));
	232
	233	/* Type */
	234	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
	235	goto out;
	236	ent.type = strcmp(buf1, "user") == 0 ?
	237	IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
	238
	239	/* ID */
	240	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
	241	goto out;
	242	ent.id = simple_strtoul(buf1, &bp, 10);
	243	if (bp == buf1)
	244	goto out;
	245
	246	/* expiry */
	247	ent.h.expiry_time = get_expiry(&buf);
	248	if (ent.h.expiry_time == 0)
	249	goto out;
	250
f9ecc921 N	251	error = -ENOMEM;
	252	res = idtoname_lookup(&ent);
	253	if (!res)
	254	goto out;
	255
1da177e4	256	/* Name */
c9b6cbe5 BF	257	error = -EINVAL;
	258	len = qword_get(&buf, buf1, PAGE_SIZE);
	259	if (len < 0)
1da177e4	260	goto out;
c9b6cbe5	261	if (len == 0)
1da177e4	262	set_bit(CACHE_NEGATIVE, &ent.h.flags);
d4395e03 BF	263	else if (len >= IDMAP_NAMESZ)
	264	goto out;
	265	else
1da177e4	266	memcpy(ent.name, buf1, sizeof(ent.name));
1da177e4	267	error = -ENOMEM;
f9ecc921 N	268	res = idtoname_update(&ent, res);
f9ecc921 N	269	if (res == NULL)
1da177e4 LT	270	goto out;
1da177e4 LT	271
baab935f	272	cache_put(&res->h, &idtoname_cache);
1da177e4 LT	273
	274	error = 0;
	275	out:
	276	kfree(buf1);
	277
	278	return error;
	279	}
	280
f9ecc921 N	281
	282	static struct ent *
	283	idtoname_lookup(struct ent *item)
	284	{
	285	struct cache_head *ch = sunrpc_cache_lookup(&idtoname_cache,
	286	&item->h,
	287	idtoname_hash(item));
	288	if (ch)
	289	return container_of(ch, struct ent, h);
	290	else
	291	return NULL;
	292	}
	293
	294	static struct ent *
	295	idtoname_update(struct ent new, struct ent old)
	296	{
	297	struct cache_head *ch = sunrpc_cache_update(&idtoname_cache,
	298	&new->h, &old->h,
	299	idtoname_hash(new));
	300	if (ch)
	301	return container_of(ch, struct ent, h);
	302	else
	303	return NULL;
	304	}
	305
1da177e4 LT	306
	307	/*
	308	* Name -> ID cache
	309	*/
	310
	311	static struct cache_head *nametoid_table[ENT_HASHMAX];
	312
	313	static inline int
	314	nametoid_hash(struct ent *ent)
	315	{
	316	return hash_str(ent->name, ENT_HASHBITS);
	317	}
	318
fd39ca9a	319	static void
1da177e4 LT	320	nametoid_request(struct cache_detail cd, struct cache_head ch, char **bpp,
	321	int *blen)
	322	{
	323	struct ent *ent = container_of(ch, struct ent, h);
	324
	325	qword_add(bpp, blen, ent->authname);
	326	qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
	327	qword_add(bpp, blen, ent->name);
	328
	329	(*bpp)[-1] = '\n';
	330	}
	331
bc74b4f5 TM	332	static int
	333	nametoid_upcall(struct cache_detail cd, struct cache_head ch)
	334	{
	335	return sunrpc_cache_pipe_upcall(cd, ch, nametoid_request);
	336	}
	337
f9ecc921 N	338	static int
f9ecc921 N	339	nametoid_match(struct cache_head ca, struct cache_head cb)
1da177e4	340	{
f9ecc921 N	341	struct ent *a = container_of(ca, struct ent, h);
	342	struct ent *b = container_of(cb, struct ent, h);
	343
1da177e4 LT	344	return (a->type == b->type && strcmp(a->name, b->name) == 0 &&
	345	strcmp(a->authname, b->authname) == 0);
	346	}
	347
	348	static int
	349	nametoid_show(struct seq_file m, struct cache_detail cd, struct cache_head *h)
	350	{
	351	struct ent *ent;
	352
	353	if (h == NULL) {
	354	seq_puts(m, "#domain type name [id]\n");
	355	return 0;
	356	}
	357	ent = container_of(h, struct ent, h);
	358	seq_printf(m, "%s %s %s", ent->authname,
	359	ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
	360	ent->name);
	361	if (test_bit(CACHE_VALID, &h->flags))
0a725fc4	362	seq_printf(m, " %u", ent->id);
1da177e4 LT	363	seq_printf(m, "\n");
	364	return 0;
	365	}
	366
f9ecc921 N	367	static struct ent nametoid_lookup(struct ent );
f9ecc921 N	368	static struct ent nametoid_update(struct ent , struct ent *);
fd39ca9a	369	static int nametoid_parse(struct cache_detail , char , int);
1da177e4	370
fd39ca9a	371	static struct cache_detail nametoid_cache = {
f35279d3	372	.owner = THIS_MODULE,
1da177e4 LT	373	.hash_size = ENT_HASHMAX,
	374	.hash_table = nametoid_table,
	375	.name = "nfs4.nametoid",
	376	.cache_put = ent_put,
bc74b4f5	377	.cache_upcall = nametoid_upcall,
1da177e4 LT	378	.cache_parse = nametoid_parse,
	379	.cache_show = nametoid_show,
	380	.warn_no_listener = warn_no_idmapd,
f9ecc921 N	381	.match = nametoid_match,
	382	.init = ent_init,
	383	.update = ent_init,
	384	.alloc = ent_alloc,
1da177e4 LT	385	};
1da177e4 LT	386
fd39ca9a	387	static int
1da177e4 LT	388	nametoid_parse(struct cache_detail cd, char buf, int buflen)
	389	{
	390	struct ent ent, *res;
	391	char *buf1;
	392	int error = -EINVAL;
	393
	394	if (buf[buflen - 1] != '\n')
	395	return (-EINVAL);
	396	buf[buflen - 1]= '\0';
	397
	398	buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
	399	if (buf1 == NULL)
	400	return (-ENOMEM);
	401
	402	memset(&ent, 0, sizeof(ent));
	403
	404	/* Authentication name */
	405	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
	406	goto out;
	407	memcpy(ent.authname, buf1, sizeof(ent.authname));
	408
	409	/* Type */
	410	if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
	411	goto out;
	412	ent.type = strcmp(buf1, "user") == 0 ?
	413	IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
	414
	415	/* Name */
	416	error = qword_get(&buf, buf1, PAGE_SIZE);
	417	if (error <= 0 \|\| error >= IDMAP_NAMESZ)
	418	goto out;
	419	memcpy(ent.name, buf1, sizeof(ent.name));
	420
	421	/* expiry */
	422	ent.h.expiry_time = get_expiry(&buf);
	423	if (ent.h.expiry_time == 0)
	424	goto out;
	425
	426	/* ID */
	427	error = get_int(&buf, &ent.id);
	428	if (error == -EINVAL)
	429	goto out;
	430	if (error == -ENOENT)
	431	set_bit(CACHE_NEGATIVE, &ent.h.flags);
	432
	433	error = -ENOMEM;
f9ecc921 N	434	res = nametoid_lookup(&ent);
	435	if (res == NULL)
	436	goto out;
	437	res = nametoid_update(&ent, res);
	438	if (res == NULL)
1da177e4 LT	439	goto out;
1da177e4 LT	440
baab935f	441	cache_put(&res->h, &nametoid_cache);
1da177e4 LT	442	error = 0;
	443	out:
	444	kfree(buf1);
	445
	446	return (error);
	447	}
	448
f9ecc921 N	449
	450	static struct ent *
	451	nametoid_lookup(struct ent *item)
	452	{
	453	struct cache_head *ch = sunrpc_cache_lookup(&nametoid_cache,
	454	&item->h,
	455	nametoid_hash(item));
	456	if (ch)
	457	return container_of(ch, struct ent, h);
	458	else
	459	return NULL;
	460	}
	461
	462	static struct ent *
	463	nametoid_update(struct ent new, struct ent old)
	464	{
	465	struct cache_head *ch = sunrpc_cache_update(&nametoid_cache,
	466	&new->h, &old->h,
	467	nametoid_hash(new));
	468	if (ch)
	469	return container_of(ch, struct ent, h);
	470	else
	471	return NULL;
	472	}
1da177e4 LT	473
	474	/*
	475	* Exported API
	476	*/
	477
dbf847ec	478	int
1da177e4 LT	479	nfsd_idmap_init(void)
1da177e4 LT	480	{
dbf847ec BF	481	int rv;
	482
	483	rv = cache_register(&idtoname_cache);
	484	if (rv)
	485	return rv;
	486	rv = cache_register(&nametoid_cache);
	487	if (rv)
	488	cache_unregister(&idtoname_cache);
	489	return rv;
1da177e4 LT	490	}
	491
	492	void
	493	nfsd_idmap_shutdown(void)
	494	{
df95a9d4 BF	495	cache_unregister(&idtoname_cache);
df95a9d4 BF	496	cache_unregister(&nametoid_cache);
1da177e4 LT	497	}
	498
	499	/*
	500	* Deferred request handling
	501	*/
	502
	503	struct idmap_defer_req {
	504	struct cache_req req;
	505	struct cache_deferred_req deferred_req;
	506	wait_queue_head_t waitq;
	507	atomic_t count;
	508	};
	509
	510	static inline void
	511	put_mdr(struct idmap_defer_req *mdr)
	512	{
	513	if (atomic_dec_and_test(&mdr->count))
	514	kfree(mdr);
	515	}
	516
	517	static inline void
	518	get_mdr(struct idmap_defer_req *mdr)
	519	{
	520	atomic_inc(&mdr->count);
	521	}
	522
	523	static void
	524	idmap_revisit(struct cache_deferred_req *dreq, int toomany)
	525	{
	526	struct idmap_defer_req *mdr =
	527	container_of(dreq, struct idmap_defer_req, deferred_req);
	528
	529	wake_up(&mdr->waitq);
	530	put_mdr(mdr);
	531	}
	532
	533	static struct cache_deferred_req *
	534	idmap_defer(struct cache_req *req)
	535	{
	536	struct idmap_defer_req *mdr =
	537	container_of(req, struct idmap_defer_req, req);
	538
	539	mdr->deferred_req.revisit = idmap_revisit;
	540	get_mdr(mdr);
	541	return (&mdr->deferred_req);
	542	}
	543
	544	static inline int
f9ecc921	545	do_idmap_lookup(struct ent (lookup_fn)(struct ent ), struct ent key,
1da177e4 LT	546	struct cache_detail detail, struct ent *item,
	547	struct idmap_defer_req *mdr)
	548	{
f9ecc921	549	*item = lookup_fn(key);
1da177e4 LT	550	if (!*item)
	551	return -ENOMEM;
	552	return cache_check(detail, &(*item)->h, &mdr->req);
	553	}
	554
	555	static inline int
f9ecc921	556	do_idmap_lookup_nowait(struct ent (lookup_fn)(struct ent *),
1da177e4 LT	557	struct ent key, struct cache_detail detail,
	558	struct ent **item)
	559	{
	560	int ret = -ENOMEM;
	561
f9ecc921	562	*item = lookup_fn(key);
1da177e4 LT	563	if (!*item)
	564	goto out_err;
	565	ret = -ETIMEDOUT;
	566	if (!test_bit(CACHE_VALID, &(*item)->h.flags)
	567	\|\| (*item)->h.expiry_time < get_seconds()
	568	\|\| detail->flush_time > (*item)->h.last_refresh)
	569	goto out_put;
	570	ret = -ENOENT;
	571	if (test_bit(CACHE_NEGATIVE, &(*item)->h.flags))
	572	goto out_put;
	573	return 0;
	574	out_put:
baab935f	575	cache_put(&(*item)->h, detail);
1da177e4 LT	576	out_err:
	577	*item = NULL;
	578	return ret;
	579	}
	580
	581	static int
	582	idmap_lookup(struct svc_rqst *rqstp,
f9ecc921	583	struct ent (lookup_fn)(struct ent ), struct ent key,
1da177e4 LT	584	struct cache_detail detail, struct ent *item)
	585	{
	586	struct idmap_defer_req *mdr;
	587	int ret;
	588
f8314dc6	589	mdr = kzalloc(sizeof(*mdr), GFP_KERNEL);
1da177e4 LT	590	if (!mdr)
1da177e4 LT	591	return -ENOMEM;
1da177e4 LT	592	atomic_set(&mdr->count, 1);
	593	init_waitqueue_head(&mdr->waitq);
	594	mdr->req.defer = idmap_defer;
	595	ret = do_idmap_lookup(lookup_fn, key, detail, item, mdr);
	596	if (ret == -EAGAIN) {
	597	wait_event_interruptible_timeout(mdr->waitq,
	598	test_bit(CACHE_VALID, &(item)->h.flags), 1 HZ);
	599	ret = do_idmap_lookup_nowait(lookup_fn, key, detail, item);
	600	}
	601	put_mdr(mdr);
	602	return ret;
	603	}
	604
3ab4d8b1 BF	605	static char *
	606	rqst_authname(struct svc_rqst *rqstp)
	607	{
	608	struct auth_domain *clp;
	609
	610	clp = rqstp->rq_gssclient ? rqstp->rq_gssclient : rqstp->rq_client;
	611	return clp->name;
	612	}
	613
1da177e4 LT	614	static int
	615	idmap_name_to_id(struct svc_rqst rqstp, int type, const char name, u32 namelen,
	616	uid_t *id)
	617	{
	618	struct ent *item, key = {
	619	.type = type,
	620	};
	621	int ret;
	622
	623	if (namelen + 1 > sizeof(key.name))
	624	return -EINVAL;
	625	memcpy(key.name, name, namelen);
	626	key.name[namelen] = '\0';
3ab4d8b1	627	strlcpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
1da177e4 LT	628	ret = idmap_lookup(rqstp, nametoid_lookup, &key, &nametoid_cache, &item);
	629	if (ret == -ENOENT)
	630	ret = -ESRCH; /* nfserr_badname */
	631	if (ret)
	632	return ret;
	633	*id = item->id;
baab935f	634	cache_put(&item->h, &nametoid_cache);
1da177e4 LT	635	return 0;
	636	}
	637
	638	static int
	639	idmap_id_to_name(struct svc_rqst rqstp, int type, uid_t id, char name)
	640	{
	641	struct ent *item, key = {
	642	.id = id,
	643	.type = type,
	644	};
	645	int ret;
	646
3ab4d8b1	647	strlcpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
1da177e4 LT	648	ret = idmap_lookup(rqstp, idtoname_lookup, &key, &idtoname_cache, &item);
	649	if (ret == -ENOENT)
	650	return sprintf(name, "%u", id);
	651	if (ret)
	652	return ret;
	653	ret = strlen(item->name);
	654	BUG_ON(ret > IDMAP_NAMESZ);
	655	memcpy(name, item->name, ret);
baab935f	656	cache_put(&item->h, &idtoname_cache);
1da177e4 LT	657	return ret;
	658	}
	659
	660	int
	661	nfsd_map_name_to_uid(struct svc_rqst rqstp, const char name, size_t namelen,
	662	__u32 *id)
	663	{
	664	return idmap_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, id);
	665	}
	666
	667	int
	668	nfsd_map_name_to_gid(struct svc_rqst rqstp, const char name, size_t namelen,
	669	__u32 *id)
	670	{
	671	return idmap_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, id);
	672	}
	673
	674	int
	675	nfsd_map_uid_to_name(struct svc_rqst rqstp, __u32 id, char name)
	676	{
	677	return idmap_id_to_name(rqstp, IDMAP_TYPE_USER, id, name);
	678	}
	679
	680	int
	681	nfsd_map_gid_to_name(struct svc_rqst rqstp, __u32 id, char name)
	682	{
	683	return idmap_id_to_name(rqstp, IDMAP_TYPE_GROUP, id, name);
	684	}