[mirror_ubuntu-bionic-kernel.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/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_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)
{
	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,
};

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_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_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
 */

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