/*
* 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/seq_file.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/sunrpc/svc_xprt.h>
#include <net/net_namespace.h>
#include "idmap.h"
#include "nfsd.h"
#include "netns.h"
#include "vfs.h"
/*
* Turn off idmapping when using AUTH_SYS.
*/
static bool nfs4_disable_idmapping = true;
module_param(nfs4_disable_idmapping, bool, 0644);
MODULE_PARM_DESC(nfs4_disable_idmapping,
"Turn off server's NFSv4 idmapping when using 'sec=sys'");
/*
* Cache entry
*/
/*
* XXX we know that IDMAP_NAMESZ < PAGE_SIZE, but it's ugly to rely on
* that.
*/
struct ent {
struct cache_head h;
int type; /* User / Group */
u32 id;
char name[IDMAP_NAMESZ];
char authname[IDMAP_NAMESZ];
struct rcu_head rcu_head;
};
/* Common entry handling */
#define ENT_HASHBITS 8
#define ENT_HASHMAX (1 << ENT_HASHBITS)
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;
strscpy(new->name, itm->name, sizeof(new->name));
strscpy(new->authname, itm->authname, sizeof(new->authname));
}
static void
ent_put(struct kref *ref)
{
struct ent *map = container_of(ref, struct ent, h.ref);
kfree_rcu(map, rcu_head);
}
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 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 int
idtoname_upcall(struct cache_detail *cd, struct cache_head *h)
{
return sunrpc_cache_pipe_upcall_timeout(cd, h);
}
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_putc(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 cache_detail *, struct ent *);
static struct ent *idtoname_update(struct cache_detail *, struct ent *,
struct ent *);
static const struct cache_detail idtoname_cache_template = {
.owner = THIS_MODULE,
.hash_size = ENT_HASHMAX,
.name = "nfs4.idtoname",
.cache_put = ent_put,
.cache_upcall = idtoname_upcall,
.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 */
len = qword_get(&buf, buf1, PAGE_SIZE);
if (len <= 0 || len >= IDMAP_NAMESZ)
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 */
error = get_expiry(&buf, &ent.h.expiry_time);
if (error)
goto out;
error = -ENOMEM;
res = idtoname_lookup(cd, &ent);
if (!res)
goto out;
/* Name */
error = -EINVAL;
len = qword_get(&buf, buf1, PAGE_SIZE);
if (len < 0 || len >= IDMAP_NAMESZ)
goto out;
if (len == 0)
set_bit(CACHE_NEGATIVE, &ent.h.flags);
else
memcpy(ent.name, buf1, sizeof(ent.name));
error = -ENOMEM;
res = idtoname_update(cd, &ent, res);
if (res == NULL)
goto out;
cache_put(&res->h, cd);
error = 0;
out:
kfree(buf1);
return error;
}
static struct ent *
idtoname_lookup(struct cache_detail *cd, struct ent *item)
{
struct cache_head *ch = sunrpc_cache_lookup_rcu(cd, &item->h,
idtoname_hash(item));
if (ch)
return container_of(ch, struct ent, h);
else
return NULL;
}
static struct ent *
idtoname_update(struct cache_detail *cd, struct ent *new, struct ent *old)
{
struct cache_head *ch = sunrpc_cache_update(cd, &new->h, &old->h,
idtoname_hash(new));
if (ch)
return container_of(ch, struct ent, h);
else
return NULL;
}
/*
* Name -> ID cache
*/
static inline int
nametoid_hash(struct ent *ent)
{
return hash_str(ent->name, ENT_HASHBITS);
}
static int
nametoid_upcall(struct cache_detail *cd, struct cache_head *h)
{
return sunrpc_cache_pipe_upcall_timeout(cd, h);
}
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_putc(m, '\n');
return 0;
}
static struct ent *nametoid_lookup(struct cache_detail *, struct ent *);
static struct ent *nametoid_update(struct cache_detail *, struct ent *,
struct ent *);
static int nametoid_parse(struct cache_detail *, char *, int);
static const struct cache_detail nametoid_cache_template = {
.owner = THIS_MODULE,
.hash_size = ENT_HASHMAX,
.name = "nfs4.nametoid",
.cache_put = ent_put,
.cache_upcall = nametoid_upcall,
.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 len, 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 */
len = qword_get(&buf, buf1, PAGE_SIZE);
if (len <= 0 || len >= IDMAP_NAMESZ)
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 */
len = qword_get(&buf, buf1, PAGE_SIZE);
if (len <= 0 || len >= IDMAP_NAMESZ)
goto out;
memcpy(ent.name, buf1, sizeof(ent.name));
/* expiry */
error = get_expiry(&buf, &ent.h.expiry_time);
if (error)
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(cd, &ent);
if (res == NULL)
goto out;
res = nametoid_update(cd, &ent, res);
if (res == NULL)
goto out;
cache_put(&res->h, cd);
error = 0;
out:
kfree(buf1);
return (error);
}
static struct ent *
nametoid_lookup(struct cache_detail *cd, struct ent *item)
{
struct cache_head *ch = sunrpc_cache_lookup_rcu(cd, &item->h,
nametoid_hash(item));
if (ch)
return container_of(ch, struct ent, h);
else
return NULL;
}
static struct ent *
nametoid_update(struct cache_detail *cd, struct ent *new, struct ent *old)
{
struct cache_head *ch = sunrpc_cache_update(cd, &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(struct net *net)
{
int rv;
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
nn->idtoname_cache = cache_create_net(&idtoname_cache_template, net);
if (IS_ERR(nn->idtoname_cache))
return PTR_ERR(nn->idtoname_cache);
rv = cache_register_net(nn->idtoname_cache, net);
if (rv)
goto destroy_idtoname_cache;
nn->nametoid_cache = cache_create_net(&nametoid_cache_template, net);
if (IS_ERR(nn->nametoid_cache)) {
rv = PTR_ERR(nn->nametoid_cache);
goto unregister_idtoname_cache;
}
rv = cache_register_net(nn->nametoid_cache, net);
if (rv)
goto destroy_nametoid_cache;
return 0;
destroy_nametoid_cache:
cache_destroy_net(nn->nametoid_cache, net);
unregister_idtoname_cache:
cache_unregister_net(nn->idtoname_cache, net);
destroy_idtoname_cache:
cache_destroy_net(nn->idtoname_cache, net);
return rv;
}
void
nfsd_idmap_shutdown(struct net *net)
{
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
cache_unregister_net(nn->idtoname_cache, net);
cache_unregister_net(nn->nametoid_cache, net);
cache_destroy_net(nn->idtoname_cache, net);
cache_destroy_net(nn->nametoid_cache, net);
}
static int
idmap_lookup(struct svc_rqst *rqstp,
struct ent *(*lookup_fn)(struct cache_detail *, struct ent *),
struct ent *key, struct cache_detail *detail, struct ent **item)
{
int ret;
*item = lookup_fn(detail, key);
if (!*item)
return -ENOMEM;
retry:
ret = cache_check(detail, &(*item)->h, &rqstp->rq_chandle);
if (ret == -ETIMEDOUT) {
struct ent *prev_item = *item;
*item = lookup_fn(detail, key);
if (*item != prev_item)
goto retry;
cache_put(&(*item)->h, detail);
}
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 __be32
idmap_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen,
u32 *id)
{
struct ent *item, key = {
.type = type,
};
int ret;
struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
if (namelen + 1 > sizeof(key.name))
return nfserr_badowner;
memcpy(key.name, name, namelen);
key.name[namelen] = '\0';
strscpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
ret = idmap_lookup(rqstp, nametoid_lookup, &key, nn->nametoid_cache, &item);
if (ret == -ENOENT)
return nfserr_badowner;
if (ret)
return nfserrno(ret);
*id = item->id;
cache_put(&item->h, nn->nametoid_cache);
return 0;
}
static __be32 encode_ascii_id(struct xdr_stream *xdr, u32 id)
{
char buf[11];
int len;
__be32 *p;
len = sprintf(buf, "%u", id);
p = xdr_reserve_space(xdr, len + 4);
if (!p)
return nfserr_resource;
p = xdr_encode_opaque(p, buf, len);
return 0;
}
static __be32 idmap_id_to_name(struct xdr_stream *xdr,
struct svc_rqst *rqstp, int type, u32 id)
{
struct ent *item, key = {
.id = id,
.type = type,
};
__be32 status = nfs_ok;
__be32 *p;
int ret;
struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
strscpy(key.authname, rqst_authname(rqstp), sizeof(key.authname));
ret = idmap_lookup(rqstp, idtoname_lookup, &key, nn->idtoname_cache, &item);
if (ret == -ENOENT)
return encode_ascii_id(xdr, id);
if (ret)
return nfserrno(ret);
ret = strlen(item->name);
WARN_ON_ONCE(ret > IDMAP_NAMESZ);
p = xdr_reserve_space(xdr, ret + 4);
if (unlikely(!p)) {
status = nfserr_resource;
goto out_put;
}
xdr_encode_opaque(p, item->name, ret);
out_put:
cache_put(&item->h, nn->idtoname_cache);
return status;
}
static bool
numeric_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, u32 *id)
{
int ret;
char buf[11];
if (namelen + 1 > sizeof(buf))
/* too long to represent a 32-bit id: */
return false;
/* Just to make sure it's null-terminated: */
memcpy(buf, name, namelen);
buf[namelen] = '\0';
ret = kstrtouint(buf, 10, id);
return ret == 0;
}
static __be32
do_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, u32 *id)
{
if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
if (numeric_name_to_id(rqstp, type, name, namelen, id))
return 0;
/*
* otherwise, fall through and try idmapping, for
* backwards compatibility with clients sending names:
*/
return idmap_name_to_id(rqstp, type, name, namelen, id);
}
static __be32 encode_name_from_id(struct xdr_stream *xdr,
struct svc_rqst *rqstp, int type, u32 id)
{
if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
return encode_ascii_id(xdr, id);
return idmap_id_to_name(xdr, rqstp, type, id);
}
__be32
nfsd_map_name_to_uid(struct svc_rqst *rqstp, const char *name, size_t namelen,
kuid_t *uid)
{
__be32 status;
u32 id = -1;
if (name == NULL || namelen == 0)
return nfserr_inval;
status = do_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, &id);
*uid = make_kuid(nfsd_user_namespace(rqstp), id);
if (!uid_valid(*uid))
status = nfserr_badowner;
return status;
}
__be32
nfsd_map_name_to_gid(struct svc_rqst *rqstp, const char *name, size_t namelen,
kgid_t *gid)
{
__be32 status;
u32 id = -1;
if (name == NULL || namelen == 0)
return nfserr_inval;
status = do_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, &id);
*gid = make_kgid(nfsd_user_namespace(rqstp), id);
if (!gid_valid(*gid))
status = nfserr_badowner;
return status;
}
__be32 nfsd4_encode_user(struct xdr_stream *xdr, struct svc_rqst *rqstp,
kuid_t uid)
{
u32 id = from_kuid_munged(nfsd_user_namespace(rqstp), uid);
return encode_name_from_id(xdr, rqstp, IDMAP_TYPE_USER, id);
}
__be32 nfsd4_encode_group(struct xdr_stream *xdr, struct svc_rqst *rqstp,
kgid_t gid)
{
u32 id = from_kgid_munged(nfsd_user_namespace(rqstp), gid);
return encode_name_from_id(xdr, rqstp, IDMAP_TYPE_GROUP, id);
}
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