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|
/*
* fs/nfs/idmap.c
*
* UID and GID to name mapping for clients.
*
* Copyright (c) 2002 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/types.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/nfs_idmap.h>
#include <linux/nfs_fs.h>
/**
* nfs_fattr_init_names - initialise the nfs_fattr owner_name/group_name fields
* @fattr: fully initialised struct nfs_fattr
* @owner_name: owner name string cache
* @group_name: group name string cache
*/
void nfs_fattr_init_names(struct nfs_fattr *fattr,
struct nfs4_string *owner_name,
struct nfs4_string *group_name)
{
fattr->owner_name = owner_name;
fattr->group_name = group_name;
}
static void nfs_fattr_free_owner_name(struct nfs_fattr *fattr)
{
fattr->valid &= ~NFS_ATTR_FATTR_OWNER_NAME;
kfree(fattr->owner_name->data);
}
static void nfs_fattr_free_group_name(struct nfs_fattr *fattr)
{
fattr->valid &= ~NFS_ATTR_FATTR_GROUP_NAME;
kfree(fattr->group_name->data);
}
static bool nfs_fattr_map_owner_name(struct nfs_server *server, struct nfs_fattr *fattr)
{
struct nfs4_string *owner = fattr->owner_name;
__u32 uid;
if (!(fattr->valid & NFS_ATTR_FATTR_OWNER_NAME))
return false;
if (nfs_map_name_to_uid(server, owner->data, owner->len, &uid) == 0) {
fattr->uid = uid;
fattr->valid |= NFS_ATTR_FATTR_OWNER;
}
return true;
}
static bool nfs_fattr_map_group_name(struct nfs_server *server, struct nfs_fattr *fattr)
{
struct nfs4_string *group = fattr->group_name;
__u32 gid;
if (!(fattr->valid & NFS_ATTR_FATTR_GROUP_NAME))
return false;
if (nfs_map_group_to_gid(server, group->data, group->len, &gid) == 0) {
fattr->gid = gid;
fattr->valid |= NFS_ATTR_FATTR_GROUP;
}
return true;
}
/**
* nfs_fattr_free_names - free up the NFSv4 owner and group strings
* @fattr: a fully initialised nfs_fattr structure
*/
void nfs_fattr_free_names(struct nfs_fattr *fattr)
{
if (fattr->valid & NFS_ATTR_FATTR_OWNER_NAME)
nfs_fattr_free_owner_name(fattr);
if (fattr->valid & NFS_ATTR_FATTR_GROUP_NAME)
nfs_fattr_free_group_name(fattr);
}
/**
* nfs_fattr_map_and_free_names - map owner/group strings into uid/gid and free
* @server: pointer to the filesystem nfs_server structure
* @fattr: a fully initialised nfs_fattr structure
*
* This helper maps the cached NFSv4 owner/group strings in fattr into
* their numeric uid/gid equivalents, and then frees the cached strings.
*/
void nfs_fattr_map_and_free_names(struct nfs_server *server, struct nfs_fattr *fattr)
{
if (nfs_fattr_map_owner_name(server, fattr))
nfs_fattr_free_owner_name(fattr);
if (nfs_fattr_map_group_name(server, fattr))
nfs_fattr_free_group_name(fattr);
}
static int nfs_map_string_to_numeric(const char *name, size_t namelen, __u32 *res)
{
unsigned long val;
char buf[16];
if (memchr(name, '@', namelen) != NULL || namelen >= sizeof(buf))
return 0;
memcpy(buf, name, namelen);
buf[namelen] = '\0';
if (strict_strtoul(buf, 0, &val) != 0)
return 0;
*res = val;
return 1;
}
static int nfs_map_numeric_to_string(__u32 id, char *buf, size_t buflen)
{
return snprintf(buf, buflen, "%u", id);
}
#ifdef CONFIG_NFS_USE_NEW_IDMAPPER
#include <linux/cred.h>
#include <linux/sunrpc/sched.h>
#include <linux/nfs4.h>
#include <linux/nfs_fs_sb.h>
#include <linux/keyctl.h>
#include <linux/key-type.h>
#include <linux/rcupdate.h>
#include <linux/err.h>
#include <keys/user-type.h>
#define NFS_UINT_MAXLEN 11
const struct cred *id_resolver_cache;
struct key_type key_type_id_resolver = {
.name = "id_resolver",
.instantiate = user_instantiate,
.match = user_match,
.revoke = user_revoke,
.destroy = user_destroy,
.describe = user_describe,
.read = user_read,
};
int nfs_idmap_init(void)
{
struct cred *cred;
struct key *keyring;
int ret = 0;
printk(KERN_NOTICE "NFS: Registering the %s key type\n",
key_type_id_resolver.name);
cred = prepare_kernel_cred(NULL);
if (!cred)
return -ENOMEM;
keyring = key_alloc(&key_type_keyring, ".id_resolver", 0, 0, cred,
(KEY_POS_ALL & ~KEY_POS_SETATTR) |
KEY_USR_VIEW | KEY_USR_READ,
KEY_ALLOC_NOT_IN_QUOTA);
if (IS_ERR(keyring)) {
ret = PTR_ERR(keyring);
goto failed_put_cred;
}
ret = key_instantiate_and_link(keyring, NULL, 0, NULL, NULL);
if (ret < 0)
goto failed_put_key;
ret = register_key_type(&key_type_id_resolver);
if (ret < 0)
goto failed_put_key;
cred->thread_keyring = keyring;
cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING;
id_resolver_cache = cred;
return 0;
failed_put_key:
key_put(keyring);
failed_put_cred:
put_cred(cred);
return ret;
}
void nfs_idmap_quit(void)
{
key_revoke(id_resolver_cache->thread_keyring);
unregister_key_type(&key_type_id_resolver);
put_cred(id_resolver_cache);
}
/*
* Assemble the description to pass to request_key()
* This function will allocate a new string and update dest to point
* at it. The caller is responsible for freeing dest.
*
* On error 0 is returned. Otherwise, the length of dest is returned.
*/
static ssize_t nfs_idmap_get_desc(const char *name, size_t namelen,
const char *type, size_t typelen, char **desc)
{
char *cp;
size_t desclen = typelen + namelen + 2;
*desc = kmalloc(desclen, GFP_KERNEL);
if (!*desc)
return -ENOMEM;
cp = *desc;
memcpy(cp, type, typelen);
cp += typelen;
*cp++ = ':';
memcpy(cp, name, namelen);
cp += namelen;
*cp = '\0';
return desclen;
}
static ssize_t nfs_idmap_request_key(const char *name, size_t namelen,
const char *type, void *data, size_t data_size)
{
const struct cred *saved_cred;
struct key *rkey;
char *desc;
struct user_key_payload *payload;
ssize_t ret;
ret = nfs_idmap_get_desc(name, namelen, type, strlen(type), &desc);
if (ret <= 0)
goto out;
saved_cred = override_creds(id_resolver_cache);
rkey = request_key(&key_type_id_resolver, desc, "");
revert_creds(saved_cred);
kfree(desc);
if (IS_ERR(rkey)) {
ret = PTR_ERR(rkey);
goto out;
}
rcu_read_lock();
rkey->perm |= KEY_USR_VIEW;
ret = key_validate(rkey);
if (ret < 0)
goto out_up;
payload = rcu_dereference(rkey->payload.data);
if (IS_ERR_OR_NULL(payload)) {
ret = PTR_ERR(payload);
goto out_up;
}
ret = payload->datalen;
if (ret > 0 && ret <= data_size)
memcpy(data, payload->data, ret);
else
ret = -EINVAL;
out_up:
rcu_read_unlock();
key_put(rkey);
out:
return ret;
}
/* ID -> Name */
static ssize_t nfs_idmap_lookup_name(__u32 id, const char *type, char *buf, size_t buflen)
{
char id_str[NFS_UINT_MAXLEN];
int id_len;
ssize_t ret;
id_len = snprintf(id_str, sizeof(id_str), "%u", id);
ret = nfs_idmap_request_key(id_str, id_len, type, buf, buflen);
if (ret < 0)
return -EINVAL;
return ret;
}
/* Name -> ID */
static int nfs_idmap_lookup_id(const char *name, size_t namelen,
const char *type, __u32 *id)
{
char id_str[NFS_UINT_MAXLEN];
long id_long;
ssize_t data_size;
int ret = 0;
data_size = nfs_idmap_request_key(name, namelen, type, id_str, NFS_UINT_MAXLEN);
if (data_size <= 0) {
ret = -EINVAL;
} else {
ret = strict_strtol(id_str, 10, &id_long);
*id = (__u32)id_long;
}
return ret;
}
int nfs_map_name_to_uid(const struct nfs_server *server, const char *name, size_t namelen, __u32 *uid)
{
if (nfs_map_string_to_numeric(name, namelen, uid))
return 0;
return nfs_idmap_lookup_id(name, namelen, "uid", uid);
}
int nfs_map_group_to_gid(const struct nfs_server *server, const char *name, size_t namelen, __u32 *gid)
{
if (nfs_map_string_to_numeric(name, namelen, gid))
return 0;
return nfs_idmap_lookup_id(name, namelen, "gid", gid);
}
int nfs_map_uid_to_name(const struct nfs_server *server, __u32 uid, char *buf, size_t buflen)
{
int ret = -EINVAL;
if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
ret = nfs_idmap_lookup_name(uid, "user", buf, buflen);
if (ret < 0)
ret = nfs_map_numeric_to_string(uid, buf, buflen);
return ret;
}
int nfs_map_gid_to_group(const struct nfs_server *server, __u32 gid, char *buf, size_t buflen)
{
int ret = -EINVAL;
if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
ret = nfs_idmap_lookup_name(gid, "group", buf, buflen);
if (ret < 0)
ret = nfs_map_numeric_to_string(gid, buf, buflen);
return ret;
}
#else /* CONFIG_NFS_USE_NEW_IDMAPPER not defined */
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/init.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/sched.h>
#include <linux/sunrpc/clnt.h>
#include <linux/workqueue.h>
#include <linux/sunrpc/rpc_pipe_fs.h>
#include <linux/nfs_fs.h>
#include "nfs4_fs.h"
#include "internal.h"
#define IDMAP_HASH_SZ 128
/* Default cache timeout is 10 minutes */
unsigned int nfs_idmap_cache_timeout = 600 * HZ;
static int param_set_idmap_timeout(const char *val, struct kernel_param *kp)
{
char *endp;
int num = simple_strtol(val, &endp, 0);
int jif = num * HZ;
if (endp == val || *endp || num < 0 || jif < num)
return -EINVAL;
*((int *)kp->arg) = jif;
return 0;
}
module_param_call(idmap_cache_timeout, param_set_idmap_timeout, param_get_int,
&nfs_idmap_cache_timeout, 0644);
struct idmap_hashent {
unsigned long ih_expires;
__u32 ih_id;
size_t ih_namelen;
char ih_name[IDMAP_NAMESZ];
};
struct idmap_hashtable {
__u8 h_type;
struct idmap_hashent h_entries[IDMAP_HASH_SZ];
};
struct idmap {
struct rpc_pipe *idmap_pipe;
wait_queue_head_t idmap_wq;
struct idmap_msg idmap_im;
struct mutex idmap_lock; /* Serializes upcalls */
struct mutex idmap_im_lock; /* Protects the hashtable */
struct idmap_hashtable idmap_user_hash;
struct idmap_hashtable idmap_group_hash;
};
static ssize_t idmap_pipe_downcall(struct file *, const char __user *,
size_t);
static void idmap_pipe_destroy_msg(struct rpc_pipe_msg *);
static unsigned int fnvhash32(const void *, size_t);
static const struct rpc_pipe_ops idmap_upcall_ops = {
.upcall = rpc_pipe_generic_upcall,
.downcall = idmap_pipe_downcall,
.destroy_msg = idmap_pipe_destroy_msg,
};
static void __nfs_idmap_unregister(struct rpc_pipe *pipe)
{
if (pipe->dentry)
rpc_unlink(pipe->dentry);
}
static int __nfs_idmap_register(struct dentry *dir,
struct idmap *idmap,
struct rpc_pipe *pipe)
{
struct dentry *dentry;
dentry = rpc_mkpipe_dentry(dir, "idmap", idmap, pipe);
if (IS_ERR(dentry))
return PTR_ERR(dentry);
pipe->dentry = dentry;
return 0;
}
static void nfs_idmap_unregister(struct nfs_client *clp,
struct rpc_pipe *pipe)
{
struct net *net = clp->net;
struct super_block *pipefs_sb;
pipefs_sb = rpc_get_sb_net(net);
if (pipefs_sb) {
__nfs_idmap_unregister(pipe);
rpc_put_sb_net(net);
}
}
static int nfs_idmap_register(struct nfs_client *clp,
struct idmap *idmap,
struct rpc_pipe *pipe)
{
struct net *net = clp->net;
struct super_block *pipefs_sb;
int err = 0;
pipefs_sb = rpc_get_sb_net(net);
if (pipefs_sb) {
if (clp->cl_rpcclient->cl_dentry)
err = __nfs_idmap_register(clp->cl_rpcclient->cl_dentry,
idmap, pipe);
rpc_put_sb_net(net);
}
return err;
}
int
nfs_idmap_new(struct nfs_client *clp)
{
struct idmap *idmap;
struct rpc_pipe *pipe;
int error;
BUG_ON(clp->cl_idmap != NULL);
idmap = kzalloc(sizeof(*idmap), GFP_KERNEL);
if (idmap == NULL)
return -ENOMEM;
pipe = rpc_mkpipe_data(&idmap_upcall_ops, 0);
if (IS_ERR(pipe)) {
error = PTR_ERR(pipe);
kfree(idmap);
return error;
}
error = nfs_idmap_register(clp, idmap, pipe);
if (error) {
rpc_destroy_pipe_data(pipe);
kfree(idmap);
return error;
}
idmap->idmap_pipe = pipe;
mutex_init(&idmap->idmap_lock);
mutex_init(&idmap->idmap_im_lock);
init_waitqueue_head(&idmap->idmap_wq);
idmap->idmap_user_hash.h_type = IDMAP_TYPE_USER;
idmap->idmap_group_hash.h_type = IDMAP_TYPE_GROUP;
clp->cl_idmap = idmap;
return 0;
}
void
nfs_idmap_delete(struct nfs_client *clp)
{
struct idmap *idmap = clp->cl_idmap;
if (!idmap)
return;
nfs_idmap_unregister(clp, idmap->idmap_pipe);
rpc_destroy_pipe_data(idmap->idmap_pipe);
clp->cl_idmap = NULL;
kfree(idmap);
}
static int __rpc_pipefs_event(struct nfs_client *clp, unsigned long event,
struct super_block *sb)
{
int err = 0;
switch (event) {
case RPC_PIPEFS_MOUNT:
BUG_ON(clp->cl_rpcclient->cl_dentry == NULL);
err = __nfs_idmap_register(clp->cl_rpcclient->cl_dentry,
clp->cl_idmap,
clp->cl_idmap->idmap_pipe);
break;
case RPC_PIPEFS_UMOUNT:
if (clp->cl_idmap->idmap_pipe) {
struct dentry *parent;
parent = clp->cl_idmap->idmap_pipe->dentry->d_parent;
__nfs_idmap_unregister(clp->cl_idmap->idmap_pipe);
/*
* Note: This is a dirty hack. SUNRPC hook has been
* called already but simple_rmdir() call for the
* directory returned with error because of idmap pipe
* inside. Thus now we have to remove this directory
* here.
*/
if (rpc_rmdir(parent))
printk(KERN_ERR "NFS: %s: failed to remove "
"clnt dir!\n", __func__);
}
break;
default:
printk(KERN_ERR "NFS: %s: unknown event: %ld\n", __func__,
event);
return -ENOTSUPP;
}
return err;
}
static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
void *ptr)
{
struct super_block *sb = ptr;
struct nfs_client *clp;
int error = 0;
spin_lock(&nfs_client_lock);
list_for_each_entry(clp, &nfs_client_list, cl_share_link) {
if (clp->net != sb->s_fs_info)
continue;
if (clp->rpc_ops != &nfs_v4_clientops)
continue;
error = __rpc_pipefs_event(clp, event, sb);
if (error)
break;
}
spin_unlock(&nfs_client_lock);
return error;
}
#define PIPEFS_NFS_PRIO 1
static struct notifier_block nfs_idmap_block = {
.notifier_call = rpc_pipefs_event,
.priority = SUNRPC_PIPEFS_NFS_PRIO,
};
int nfs_idmap_init(void)
{
return rpc_pipefs_notifier_register(&nfs_idmap_block);
}
void nfs_idmap_quit(void)
{
rpc_pipefs_notifier_unregister(&nfs_idmap_block);
}
/*
* Helper routines for manipulating the hashtable
*/
static inline struct idmap_hashent *
idmap_name_hash(struct idmap_hashtable* h, const char *name, size_t len)
{
return &h->h_entries[fnvhash32(name, len) % IDMAP_HASH_SZ];
}
static struct idmap_hashent *
idmap_lookup_name(struct idmap_hashtable *h, const char *name, size_t len)
{
struct idmap_hashent *he = idmap_name_hash(h, name, len);
if (he->ih_namelen != len || memcmp(he->ih_name, name, len) != 0)
return NULL;
if (time_after(jiffies, he->ih_expires))
return NULL;
return he;
}
static inline struct idmap_hashent *
idmap_id_hash(struct idmap_hashtable* h, __u32 id)
{
return &h->h_entries[fnvhash32(&id, sizeof(id)) % IDMAP_HASH_SZ];
}
static struct idmap_hashent *
idmap_lookup_id(struct idmap_hashtable *h, __u32 id)
{
struct idmap_hashent *he = idmap_id_hash(h, id);
if (he->ih_id != id || he->ih_namelen == 0)
return NULL;
if (time_after(jiffies, he->ih_expires))
return NULL;
return he;
}
/*
* Routines for allocating new entries in the hashtable.
* For now, we just have 1 entry per bucket, so it's all
* pretty trivial.
*/
static inline struct idmap_hashent *
idmap_alloc_name(struct idmap_hashtable *h, char *name, size_t len)
{
return idmap_name_hash(h, name, len);
}
static inline struct idmap_hashent *
idmap_alloc_id(struct idmap_hashtable *h, __u32 id)
{
return idmap_id_hash(h, id);
}
static void
idmap_update_entry(struct idmap_hashent *he, const char *name,
size_t namelen, __u32 id)
{
he->ih_id = id;
memcpy(he->ih_name, name, namelen);
he->ih_name[namelen] = '\0';
he->ih_namelen = namelen;
he->ih_expires = jiffies + nfs_idmap_cache_timeout;
}
/*
* Name -> ID
*/
static int
nfs_idmap_id(struct idmap *idmap, struct idmap_hashtable *h,
const char *name, size_t namelen, __u32 *id)
{
struct rpc_pipe_msg msg;
struct idmap_msg *im;
struct idmap_hashent *he;
DECLARE_WAITQUEUE(wq, current);
int ret = -EIO;
im = &idmap->idmap_im;
/*
* String sanity checks
* Note that the userland daemon expects NUL terminated strings
*/
for (;;) {
if (namelen == 0)
return -EINVAL;
if (name[namelen-1] != '\0')
break;
namelen--;
}
if (namelen >= IDMAP_NAMESZ)
return -EINVAL;
mutex_lock(&idmap->idmap_lock);
mutex_lock(&idmap->idmap_im_lock);
he = idmap_lookup_name(h, name, namelen);
if (he != NULL) {
*id = he->ih_id;
ret = 0;
goto out;
}
memset(im, 0, sizeof(*im));
memcpy(im->im_name, name, namelen);
im->im_type = h->h_type;
im->im_conv = IDMAP_CONV_NAMETOID;
memset(&msg, 0, sizeof(msg));
msg.data = im;
msg.len = sizeof(*im);
add_wait_queue(&idmap->idmap_wq, &wq);
if (rpc_queue_upcall(idmap->idmap_pipe, &msg) < 0) {
remove_wait_queue(&idmap->idmap_wq, &wq);
goto out;
}
set_current_state(TASK_UNINTERRUPTIBLE);
mutex_unlock(&idmap->idmap_im_lock);
schedule();
__set_current_state(TASK_RUNNING);
remove_wait_queue(&idmap->idmap_wq, &wq);
mutex_lock(&idmap->idmap_im_lock);
if (im->im_status & IDMAP_STATUS_SUCCESS) {
*id = im->im_id;
ret = 0;
}
out:
memset(im, 0, sizeof(*im));
mutex_unlock(&idmap->idmap_im_lock);
mutex_unlock(&idmap->idmap_lock);
return ret;
}
/*
* ID -> Name
*/
static int
nfs_idmap_name(struct idmap *idmap, struct idmap_hashtable *h,
__u32 id, char *name)
{
struct rpc_pipe_msg msg;
struct idmap_msg *im;
struct idmap_hashent *he;
DECLARE_WAITQUEUE(wq, current);
int ret = -EIO;
unsigned int len;
im = &idmap->idmap_im;
mutex_lock(&idmap->idmap_lock);
mutex_lock(&idmap->idmap_im_lock);
he = idmap_lookup_id(h, id);
if (he) {
memcpy(name, he->ih_name, he->ih_namelen);
ret = he->ih_namelen;
goto out;
}
memset(im, 0, sizeof(*im));
im->im_type = h->h_type;
im->im_conv = IDMAP_CONV_IDTONAME;
im->im_id = id;
memset(&msg, 0, sizeof(msg));
msg.data = im;
msg.len = sizeof(*im);
add_wait_queue(&idmap->idmap_wq, &wq);
if (rpc_queue_upcall(idmap->idmap_pipe, &msg) < 0) {
remove_wait_queue(&idmap->idmap_wq, &wq);
goto out;
}
set_current_state(TASK_UNINTERRUPTIBLE);
mutex_unlock(&idmap->idmap_im_lock);
schedule();
__set_current_state(TASK_RUNNING);
remove_wait_queue(&idmap->idmap_wq, &wq);
mutex_lock(&idmap->idmap_im_lock);
if (im->im_status & IDMAP_STATUS_SUCCESS) {
if ((len = strnlen(im->im_name, IDMAP_NAMESZ)) == 0)
goto out;
memcpy(name, im->im_name, len);
ret = len;
}
out:
memset(im, 0, sizeof(*im));
mutex_unlock(&idmap->idmap_im_lock);
mutex_unlock(&idmap->idmap_lock);
return ret;
}
static ssize_t
idmap_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
{
struct rpc_inode *rpci = RPC_I(filp->f_path.dentry->d_inode);
struct idmap *idmap = (struct idmap *)rpci->private;
struct idmap_msg im_in, *im = &idmap->idmap_im;
struct idmap_hashtable *h;
struct idmap_hashent *he = NULL;
size_t namelen_in;
int ret;
if (mlen != sizeof(im_in))
return -ENOSPC;
if (copy_from_user(&im_in, src, mlen) != 0)
return -EFAULT;
mutex_lock(&idmap->idmap_im_lock);
ret = mlen;
im->im_status = im_in.im_status;
/* If we got an error, terminate now, and wake up pending upcalls */
if (!(im_in.im_status & IDMAP_STATUS_SUCCESS)) {
wake_up(&idmap->idmap_wq);
goto out;
}
/* Sanity checking of strings */
ret = -EINVAL;
namelen_in = strnlen(im_in.im_name, IDMAP_NAMESZ);
if (namelen_in == 0 || namelen_in == IDMAP_NAMESZ)
goto out;
switch (im_in.im_type) {
case IDMAP_TYPE_USER:
h = &idmap->idmap_user_hash;
break;
case IDMAP_TYPE_GROUP:
h = &idmap->idmap_group_hash;
break;
default:
goto out;
}
switch (im_in.im_conv) {
case IDMAP_CONV_IDTONAME:
/* Did we match the current upcall? */
if (im->im_conv == IDMAP_CONV_IDTONAME
&& im->im_type == im_in.im_type
&& im->im_id == im_in.im_id) {
/* Yes: copy string, including the terminating '\0' */
memcpy(im->im_name, im_in.im_name, namelen_in);
im->im_name[namelen_in] = '\0';
wake_up(&idmap->idmap_wq);
}
he = idmap_alloc_id(h, im_in.im_id);
break;
case IDMAP_CONV_NAMETOID:
/* Did we match the current upcall? */
if (im->im_conv == IDMAP_CONV_NAMETOID
&& im->im_type == im_in.im_type
&& strnlen(im->im_name, IDMAP_NAMESZ) == namelen_in
&& memcmp(im->im_name, im_in.im_name, namelen_in) == 0) {
im->im_id = im_in.im_id;
wake_up(&idmap->idmap_wq);
}
he = idmap_alloc_name(h, im_in.im_name, namelen_in);
break;
default:
goto out;
}
/* If the entry is valid, also copy it to the cache */
if (he != NULL)
idmap_update_entry(he, im_in.im_name, namelen_in, im_in.im_id);
ret = mlen;
out:
mutex_unlock(&idmap->idmap_im_lock);
return ret;
}
static void
idmap_pipe_destroy_msg(struct rpc_pipe_msg *msg)
{
struct idmap_msg *im = msg->data;
struct idmap *idmap = container_of(im, struct idmap, idmap_im);
if (msg->errno >= 0)
return;
mutex_lock(&idmap->idmap_im_lock);
im->im_status = IDMAP_STATUS_LOOKUPFAIL;
wake_up(&idmap->idmap_wq);
mutex_unlock(&idmap->idmap_im_lock);
}
/*
* Fowler/Noll/Vo hash
* http://www.isthe.com/chongo/tech/comp/fnv/
*/
#define FNV_P_32 ((unsigned int)0x01000193) /* 16777619 */
#define FNV_1_32 ((unsigned int)0x811c9dc5) /* 2166136261 */
static unsigned int fnvhash32(const void *buf, size_t buflen)
{
const unsigned char *p, *end = (const unsigned char *)buf + buflen;
unsigned int hash = FNV_1_32;
for (p = buf; p < end; p++) {
hash *= FNV_P_32;
hash ^= (unsigned int)*p;
}
return hash;
}
int nfs_map_name_to_uid(const struct nfs_server *server, const char *name, size_t namelen, __u32 *uid)
{
struct idmap *idmap = server->nfs_client->cl_idmap;
if (nfs_map_string_to_numeric(name, namelen, uid))
return 0;
return nfs_idmap_id(idmap, &idmap->idmap_user_hash, name, namelen, uid);
}
int nfs_map_group_to_gid(const struct nfs_server *server, const char *name, size_t namelen, __u32 *uid)
{
struct idmap *idmap = server->nfs_client->cl_idmap;
if (nfs_map_string_to_numeric(name, namelen, uid))
return 0;
return nfs_idmap_id(idmap, &idmap->idmap_group_hash, name, namelen, uid);
}
int nfs_map_uid_to_name(const struct nfs_server *server, __u32 uid, char *buf, size_t buflen)
{
struct idmap *idmap = server->nfs_client->cl_idmap;
int ret = -EINVAL;
if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
ret = nfs_idmap_name(idmap, &idmap->idmap_user_hash, uid, buf);
if (ret < 0)
ret = nfs_map_numeric_to_string(uid, buf, buflen);
return ret;
}
int nfs_map_gid_to_group(const struct nfs_server *server, __u32 uid, char *buf, size_t buflen)
{
struct idmap *idmap = server->nfs_client->cl_idmap;
int ret = -EINVAL;
if (!(server->caps & NFS_CAP_UIDGID_NOMAP))
ret = nfs_idmap_name(idmap, &idmap->idmap_group_hash, uid, buf);
if (ret < 0)
ret = nfs_map_numeric_to_string(uid, buf, buflen);
return ret;
}
#endif /* CONFIG_NFS_USE_NEW_IDMAPPER */
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