microsoft
/
WSL2-Linux-Kernel
зеркало из https://github.com/microsoft/WSL2-Linux-Kernel.git
1
0
Форкнуть 0
Код Задачи Пакеты Проекты Релизы Вики Активность
WSL2-Linux-Kernel/fs/nfsd/export.c

1336 строки
33 KiB
C
Исходник Ответственный История

// SPDX-License-Identifier: GPL-2.0
/*
* NFS exporting and validation.
*
* We maintain a list of clients, each of which has a list of
* exports. To export an fs to a given client, you first have
* to create the client entry with NFSCTL_ADDCLIENT, which
* creates a client control block and adds it to the hash
* table. Then, you call NFSCTL_EXPORT for each fs.
*
*
* Copyright (C) 1995, 1996 Olaf Kirch, <okir@monad.swb.de>
*/
#include <linux/slab.h>
#include <linux/namei.h>
#include <linux/module.h>
#include <linux/exportfs.h>
#include <linux/sunrpc/svc_xprt.h>
#include "nfsd.h"
#include "nfsfh.h"
#include "netns.h"
#include "pnfs.h"
#include "filecache.h"
#include "trace.h"
#define NFSDDBG_FACILITY NFSDDBG_EXPORT
/*
* We have two caches.
* One maps client+vfsmnt+dentry to export options - the export map
* The other maps client+filehandle-fragment to export options. - the expkey map
*
* The export options are actually stored in the first map, and the
* second map contains a reference to the entry in the first map.
*/
#define EXPKEY_HASHBITS 8
#define EXPKEY_HASHMAX (1 << EXPKEY_HASHBITS)
#define EXPKEY_HASHMASK (EXPKEY_HASHMAX -1)
static void expkey_put(struct kref *ref)
{
struct svc_expkey *key = container_of(ref, struct svc_expkey, h.ref);
if (test_bit(CACHE_VALID, &key->h.flags) &&
!test_bit(CACHE_NEGATIVE, &key->h.flags))
path_put(&key->ek_path);
auth_domain_put(key->ek_client);
kfree_rcu(key, ek_rcu);
}
static int expkey_upcall(struct cache_detail *cd, struct cache_head *h)
{
return sunrpc_cache_pipe_upcall(cd, h);
}
static void expkey_request(struct cache_detail *cd,
struct cache_head *h,
char **bpp, int *blen)
{
/* client fsidtype \xfsid */
struct svc_expkey *ek = container_of(h, struct svc_expkey, h);
char type[5];
qword_add(bpp, blen, ek->ek_client->name);
snprintf(type, 5, "%d", ek->ek_fsidtype);
qword_add(bpp, blen, type);
qword_addhex(bpp, blen, (char*)ek->ek_fsid, key_len(ek->ek_fsidtype));
(*bpp)[-1] = '\n';
}
static struct svc_expkey *svc_expkey_update(struct cache_detail *cd, struct svc_expkey *new,
struct svc_expkey *old);
static struct svc_expkey *svc_expkey_lookup(struct cache_detail *cd, struct svc_expkey *);
static int expkey_parse(struct cache_detail *cd, char *mesg, int mlen)
{
/* client fsidtype fsid expiry [path] */
char *buf;
int len;
struct auth_domain *dom = NULL;
int err;
int fsidtype;
char *ep;
struct svc_expkey key;
struct svc_expkey *ek = NULL;
if (mesg[mlen - 1] != '\n')
return -EINVAL;
mesg[mlen-1] = 0;
buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
err = -ENOMEM;
if (!buf)
goto out;
err = -EINVAL;
if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
goto out;
err = -ENOENT;
dom = auth_domain_find(buf);
if (!dom)
goto out;
dprintk("found domain %s\n", buf);
err = -EINVAL;
if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
goto out;
fsidtype = simple_strtoul(buf, &ep, 10);
if (*ep)
goto out;
dprintk("found fsidtype %d\n", fsidtype);
if (key_len(fsidtype)==0) /* invalid type */
goto out;
if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
goto out;
dprintk("found fsid length %d\n", len);
if (len != key_len(fsidtype))
goto out;
/* OK, we seem to have a valid key */
key.h.flags = 0;
key.h.expiry_time = get_expiry(&mesg);
if (key.h.expiry_time == 0)
goto out;
key.ek_client = dom;
key.ek_fsidtype = fsidtype;
memcpy(key.ek_fsid, buf, len);
ek = svc_expkey_lookup(cd, &key);
err = -ENOMEM;
if (!ek)
goto out;
/* now we want a pathname, or empty meaning NEGATIVE */
err = -EINVAL;
len = qword_get(&mesg, buf, PAGE_SIZE);
if (len < 0)
goto out;
dprintk("Path seems to be <%s>\n", buf);
err = 0;
if (len == 0) {
set_bit(CACHE_NEGATIVE, &key.h.flags);
ek = svc_expkey_update(cd, &key, ek);
if (ek)
trace_nfsd_expkey_update(ek, NULL);
else
err = -ENOMEM;
} else {
err = kern_path(buf, 0, &key.ek_path);
if (err)
goto out;
dprintk("Found the path %s\n", buf);
ek = svc_expkey_update(cd, &key, ek);
if (ek)
trace_nfsd_expkey_update(ek, buf);
else
err = -ENOMEM;
path_put(&key.ek_path);
}
cache_flush();
out:
if (ek)
cache_put(&ek->h, cd);
if (dom)
auth_domain_put(dom);
kfree(buf);
return err;
}
static int expkey_show(struct seq_file *m,
struct cache_detail *cd,
struct cache_head *h)
{
struct svc_expkey *ek ;
int i;
if (h ==NULL) {
seq_puts(m, "#domain fsidtype fsid [path]\n");
return 0;
}
ek = container_of(h, struct svc_expkey, h);
seq_printf(m, "%s %d 0x", ek->ek_client->name,
ek->ek_fsidtype);
for (i=0; i < key_len(ek->ek_fsidtype)/4; i++)
seq_printf(m, "%08x", ek->ek_fsid[i]);
if (test_bit(CACHE_VALID, &h->flags) &&
!test_bit(CACHE_NEGATIVE, &h->flags)) {
seq_printf(m, " ");
seq_path(m, &ek->ek_path, "\\ \t\n");
}
seq_printf(m, "\n");
return 0;
}
static inline int expkey_match (struct cache_head *a, struct cache_head *b)
{
struct svc_expkey *orig = container_of(a, struct svc_expkey, h);
struct svc_expkey *new = container_of(b, struct svc_expkey, h);
if (orig->ek_fsidtype != new->ek_fsidtype ||
orig->ek_client != new->ek_client ||
memcmp(orig->ek_fsid, new->ek_fsid, key_len(orig->ek_fsidtype)) != 0)
return 0;
return 1;
}
static inline void expkey_init(struct cache_head *cnew,
struct cache_head *citem)
{
struct svc_expkey *new = container_of(cnew, struct svc_expkey, h);
struct svc_expkey *item = container_of(citem, struct svc_expkey, h);
kref_get(&item->ek_client->ref);
new->ek_client = item->ek_client;
new->ek_fsidtype = item->ek_fsidtype;
memcpy(new->ek_fsid, item->ek_fsid, sizeof(new->ek_fsid));
}
static inline void expkey_update(struct cache_head *cnew,
struct cache_head *citem)
{
struct svc_expkey *new = container_of(cnew, struct svc_expkey, h);
struct svc_expkey *item = container_of(citem, struct svc_expkey, h);
new->ek_path = item->ek_path;
path_get(&item->ek_path);
}
static struct cache_head *expkey_alloc(void)
{
struct svc_expkey *i = kmalloc(sizeof(*i), GFP_KERNEL);
if (i)
return &i->h;
else
return NULL;
}
static void expkey_flush(void)
{
/*
* Take the nfsd_mutex here to ensure that the file cache is not
* destroyed while we're in the middle of flushing.
*/
mutex_lock(&nfsd_mutex);
nfsd_file_cache_purge(current->nsproxy->net_ns);
mutex_unlock(&nfsd_mutex);
}
static const struct cache_detail svc_expkey_cache_template = {
.owner = THIS_MODULE,
.hash_size = EXPKEY_HASHMAX,
.name = "nfsd.fh",
.cache_put = expkey_put,
.cache_upcall = expkey_upcall,
.cache_request = expkey_request,
.cache_parse = expkey_parse,
.cache_show = expkey_show,
.match = expkey_match,
.init = expkey_init,
.update = expkey_update,
.alloc = expkey_alloc,
.flush = expkey_flush,
};
static int
svc_expkey_hash(struct svc_expkey *item)
{
int hash = item->ek_fsidtype;
char * cp = (char*)item->ek_fsid;
int len = key_len(item->ek_fsidtype);
hash ^= hash_mem(cp, len, EXPKEY_HASHBITS);
hash ^= hash_ptr(item->ek_client, EXPKEY_HASHBITS);
hash &= EXPKEY_HASHMASK;
return hash;
}
static struct svc_expkey *
svc_expkey_lookup(struct cache_detail *cd, struct svc_expkey *item)
{
struct cache_head *ch;
int hash = svc_expkey_hash(item);
ch = sunrpc_cache_lookup_rcu(cd, &item->h, hash);
if (ch)
return container_of(ch, struct svc_expkey, h);
else
return NULL;
}
static struct svc_expkey *
svc_expkey_update(struct cache_detail *cd, struct svc_expkey *new,
struct svc_expkey *old)
{
struct cache_head *ch;
int hash = svc_expkey_hash(new);
ch = sunrpc_cache_update(cd, &new->h, &old->h, hash);
if (ch)
return container_of(ch, struct svc_expkey, h);
else
return NULL;
}
#define EXPORT_HASHBITS 8
#define EXPORT_HASHMAX (1<< EXPORT_HASHBITS)
static void nfsd4_fslocs_free(struct nfsd4_fs_locations *fsloc)
{
struct nfsd4_fs_location *locations = fsloc->locations;
int i;
if (!locations)
return;
for (i = 0; i < fsloc->locations_count; i++) {
kfree(locations[i].path);
kfree(locations[i].hosts);
}
kfree(locations);
fsloc->locations = NULL;
}
static void svc_export_put(struct kref *ref)
{
struct svc_export *exp = container_of(ref, struct svc_export, h.ref);
path_put(&exp->ex_path);
auth_domain_put(exp->ex_client);
nfsd4_fslocs_free(&exp->ex_fslocs);
kfree(exp->ex_uuid);
kfree_rcu(exp, ex_rcu);
}
static int svc_export_upcall(struct cache_detail *cd, struct cache_head *h)
{
return sunrpc_cache_pipe_upcall(cd, h);
}
static void svc_export_request(struct cache_detail *cd,
struct cache_head *h,
char **bpp, int *blen)
{
/* client path */
struct svc_export *exp = container_of(h, struct svc_export, h);
char *pth;
qword_add(bpp, blen, exp->ex_client->name);
pth = d_path(&exp->ex_path, *bpp, *blen);
if (IS_ERR(pth)) {
/* is this correct? */
(*bpp)[0] = '\n';
return;
}
qword_add(bpp, blen, pth);
(*bpp)[-1] = '\n';
}
static struct svc_export *svc_export_update(struct svc_export *new,
struct svc_export *old);
static struct svc_export *svc_export_lookup(struct svc_export *);
static int check_export(struct inode *inode, int *flags, unsigned char *uuid)
{
/*
* We currently export only dirs, regular files, and (for v4
* pseudoroot) symlinks.
*/
if (!S_ISDIR(inode->i_mode) &&
!S_ISLNK(inode->i_mode) &&
!S_ISREG(inode->i_mode))
return -ENOTDIR;
/*
* Mountd should never pass down a writeable V4ROOT export, but,
* just to make sure:
*/
if (*flags & NFSEXP_V4ROOT)
*flags |= NFSEXP_READONLY;
/* There are two requirements on a filesystem to be exportable.
* 1: We must be able to identify the filesystem from a number.
* either a device number (so FS_REQUIRES_DEV needed)
* or an FSID number (so NFSEXP_FSID or ->uuid is needed).
* 2: We must be able to find an inode from a filehandle.
* This means that s_export_op must be set.
*/
if (!(inode->i_sb->s_type->fs_flags & FS_REQUIRES_DEV) &&
!(*flags & NFSEXP_FSID) &&
uuid == NULL) {
dprintk("exp_export: export of non-dev fs without fsid\n");
return -EINVAL;
}
if (!inode->i_sb->s_export_op ||
!inode->i_sb->s_export_op->fh_to_dentry) {
dprintk("exp_export: export of invalid fs type.\n");
return -EINVAL;
}
if (inode->i_sb->s_export_op->flags & EXPORT_OP_NOSUBTREECHK &&
!(*flags & NFSEXP_NOSUBTREECHECK)) {
dprintk("%s: %s does not support subtree checking!\n",
__func__, inode->i_sb->s_type->name);
return -EINVAL;
}
return 0;
}
#ifdef CONFIG_NFSD_V4
static int
fsloc_parse(char **mesg, char *buf, struct nfsd4_fs_locations *fsloc)
{
int len;
int migrated, i, err;
/* more than one fsloc */
if (fsloc->locations)
return -EINVAL;
/* listsize */
err = get_uint(mesg, &fsloc->locations_count);
if (err)
return err;
if (fsloc->locations_count > MAX_FS_LOCATIONS)
return -EINVAL;
if (fsloc->locations_count == 0)
return 0;
fsloc->locations = kcalloc(fsloc->locations_count,
sizeof(struct nfsd4_fs_location),
GFP_KERNEL);
if (!fsloc->locations)
return -ENOMEM;
for (i=0; i < fsloc->locations_count; i++) {
/* colon separated host list */
err = -EINVAL;
len = qword_get(mesg, buf, PAGE_SIZE);
if (len <= 0)
goto out_free_all;
err = -ENOMEM;
fsloc->locations[i].hosts = kstrdup(buf, GFP_KERNEL);
if (!fsloc->locations[i].hosts)
goto out_free_all;
err = -EINVAL;
/* slash separated path component list */
len = qword_get(mesg, buf, PAGE_SIZE);
if (len <= 0)
goto out_free_all;
err = -ENOMEM;
fsloc->locations[i].path = kstrdup(buf, GFP_KERNEL);
if (!fsloc->locations[i].path)
goto out_free_all;
}
/* migrated */
err = get_int(mesg, &migrated);
if (err)
goto out_free_all;
err = -EINVAL;
if (migrated < 0 || migrated > 1)
goto out_free_all;
fsloc->migrated = migrated;
return 0;
out_free_all:
nfsd4_fslocs_free(fsloc);
return err;
}
static int secinfo_parse(char **mesg, char *buf, struct svc_export *exp)
{
struct exp_flavor_info *f;
u32 listsize;
int err;
/* more than one secinfo */
if (exp->ex_nflavors)
return -EINVAL;
err = get_uint(mesg, &listsize);
if (err)
return err;
if (listsize > MAX_SECINFO_LIST)
return -EINVAL;
for (f = exp->ex_flavors; f < exp->ex_flavors + listsize; f++) {
err = get_uint(mesg, &f->pseudoflavor);
if (err)
return err;
/*
* XXX: It would be nice to also check whether this
* pseudoflavor is supported, so we can discover the
* problem at export time instead of when a client fails
* to authenticate.
*/
err = get_uint(mesg, &f->flags);
if (err)
return err;
/* Only some flags are allowed to differ between flavors: */
if (~NFSEXP_SECINFO_FLAGS & (f->flags ^ exp->ex_flags))
return -EINVAL;
}
exp->ex_nflavors = listsize;
return 0;
}
#else /* CONFIG_NFSD_V4 */
static inline int
fsloc_parse(char **mesg, char *buf, struct nfsd4_fs_locations *fsloc){return 0;}
static inline int
secinfo_parse(char **mesg, char *buf, struct svc_export *exp) { return 0; }
#endif
static inline int
nfsd_uuid_parse(char **mesg, char *buf, unsigned char **puuid)
{
int len;
/* more than one uuid */
if (*puuid)
return -EINVAL;
/* expect a 16 byte uuid encoded as \xXXXX... */
len = qword_get(mesg, buf, PAGE_SIZE);
if (len != EX_UUID_LEN)
return -EINVAL;
*puuid = kmemdup(buf, EX_UUID_LEN, GFP_KERNEL);
if (*puuid == NULL)
return -ENOMEM;
return 0;
}
static int svc_export_parse(struct cache_detail *cd, char *mesg, int mlen)
{
/* client path expiry [flags anonuid anongid fsid] */
char *buf;
int len;
int err;
struct auth_domain *dom = NULL;
struct svc_export exp = {}, *expp;
int an_int;
if (mesg[mlen-1] != '\n')
return -EINVAL;
mesg[mlen-1] = 0;
buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
if (!buf)
return -ENOMEM;
/* client */
err = -EINVAL;
len = qword_get(&mesg, buf, PAGE_SIZE);
if (len <= 0)
goto out;
err = -ENOENT;
dom = auth_domain_find(buf);
if (!dom)
goto out;
/* path */
err = -EINVAL;
if ((len = qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
goto out1;
err = kern_path(buf, 0, &exp.ex_path);
if (err)
goto out1;
exp.ex_client = dom;
exp.cd = cd;
exp.ex_devid_map = NULL;
/* expiry */
err = -EINVAL;
exp.h.expiry_time = get_expiry(&mesg);
if (exp.h.expiry_time == 0)
goto out3;
/* flags */
err = get_int(&mesg, &an_int);
if (err == -ENOENT) {
err = 0;
set_bit(CACHE_NEGATIVE, &exp.h.flags);
} else {
if (err || an_int < 0)
goto out3;
exp.ex_flags= an_int;
/* anon uid */
err = get_int(&mesg, &an_int);
if (err)
goto out3;
exp.ex_anon_uid= make_kuid(current_user_ns(), an_int);
/* anon gid */
err = get_int(&mesg, &an_int);
if (err)
goto out3;
exp.ex_anon_gid= make_kgid(current_user_ns(), an_int);
/* fsid */
err = get_int(&mesg, &an_int);
if (err)
goto out3;
exp.ex_fsid = an_int;
while ((len = qword_get(&mesg, buf, PAGE_SIZE)) > 0) {
if (strcmp(buf, "fsloc") == 0)
err = fsloc_parse(&mesg, buf, &exp.ex_fslocs);
else if (strcmp(buf, "uuid") == 0)
err = nfsd_uuid_parse(&mesg, buf, &exp.ex_uuid);
else if (strcmp(buf, "secinfo") == 0)
err = secinfo_parse(&mesg, buf, &exp);
else
/* quietly ignore unknown words and anything
* following. Newer user-space can try to set
* new values, then see what the result was.
*/
break;
if (err)
goto out4;
}
err = check_export(d_inode(exp.ex_path.dentry), &exp.ex_flags,
exp.ex_uuid);
if (err)
goto out4;
/*
* No point caching this if it would immediately expire.
* Also, this protects exportfs's dummy export from the
* anon_uid/anon_gid checks:
*/
if (exp.h.expiry_time < seconds_since_boot())
goto out4;
/*
* For some reason exportfs has been passing down an
* invalid (-1) uid & gid on the "dummy" export which it
* uses to test export support. To make sure exportfs
* sees errors from check_export we therefore need to
* delay these checks till after check_export:
*/
err = -EINVAL;
if (!uid_valid(exp.ex_anon_uid))
goto out4;
if (!gid_valid(exp.ex_anon_gid))
goto out4;
err = 0;
nfsd4_setup_layout_type(&exp);
}
expp = svc_export_lookup(&exp);
if (!expp) {
err = -ENOMEM;
goto out4;
}
expp = svc_export_update(&exp, expp);
if (expp) {
trace_nfsd_export_update(expp);
cache_flush();
exp_put(expp);
} else
err = -ENOMEM;
out4:
nfsd4_fslocs_free(&exp.ex_fslocs);
kfree(exp.ex_uuid);
out3:
path_put(&exp.ex_path);
out1:
auth_domain_put(dom);
out:
kfree(buf);
return err;
}
static void exp_flags(struct seq_file *m, int flag, int fsid,
kuid_t anonu, kgid_t anong, struct nfsd4_fs_locations *fslocs);
static void show_secinfo(struct seq_file *m, struct svc_export *exp);
static int svc_export_show(struct seq_file *m,
struct cache_detail *cd,
struct cache_head *h)
{
struct svc_export *exp ;
if (h ==NULL) {
seq_puts(m, "#path domain(flags)\n");
return 0;
}
exp = container_of(h, struct svc_export, h);
seq_path(m, &exp->ex_path, " \t\n\\");
seq_putc(m, '\t');
seq_escape(m, exp->ex_client->name, " \t\n\\");
seq_putc(m, '(');
if (test_bit(CACHE_VALID, &h->flags) &&
!test_bit(CACHE_NEGATIVE, &h->flags)) {
exp_flags(m, exp->ex_flags, exp->ex_fsid,
exp->ex_anon_uid, exp->ex_anon_gid, &exp->ex_fslocs);
if (exp->ex_uuid) {
int i;
seq_puts(m, ",uuid=");
for (i = 0; i < EX_UUID_LEN; i++) {
if ((i&3) == 0 && i)
seq_putc(m, ':');
seq_printf(m, "%02x", exp->ex_uuid[i]);
}
}
show_secinfo(m, exp);
}
seq_puts(m, ")\n");
return 0;
}
static int svc_export_match(struct cache_head *a, struct cache_head *b)
{
struct svc_export *orig = container_of(a, struct svc_export, h);
struct svc_export *new = container_of(b, struct svc_export, h);
return orig->ex_client == new->ex_client &&
path_equal(&orig->ex_path, &new->ex_path);
}
static void svc_export_init(struct cache_head *cnew, struct cache_head *citem)
{
struct svc_export *new = container_of(cnew, struct svc_export, h);
struct svc_export *item = container_of(citem, struct svc_export, h);
kref_get(&item->ex_client->ref);
new->ex_client = item->ex_client;
new->ex_path = item->ex_path;
path_get(&item->ex_path);
new->ex_fslocs.locations = NULL;
new->ex_fslocs.locations_count = 0;
new->ex_fslocs.migrated = 0;
new->ex_layout_types = 0;
new->ex_uuid = NULL;
new->cd = item->cd;
}
static void export_update(struct cache_head *cnew, struct cache_head *citem)
{
struct svc_export *new = container_of(cnew, struct svc_export, h);
struct svc_export *item = container_of(citem, struct svc_export, h);
int i;
new->ex_flags = item->ex_flags;
new->ex_anon_uid = item->ex_anon_uid;
new->ex_anon_gid = item->ex_anon_gid;
new->ex_fsid = item->ex_fsid;
new->ex_devid_map = item->ex_devid_map;
item->ex_devid_map = NULL;
new->ex_uuid = item->ex_uuid;
item->ex_uuid = NULL;
new->ex_fslocs.locations = item->ex_fslocs.locations;
item->ex_fslocs.locations = NULL;
new->ex_fslocs.locations_count = item->ex_fslocs.locations_count;
item->ex_fslocs.locations_count = 0;
new->ex_fslocs.migrated = item->ex_fslocs.migrated;
item->ex_fslocs.migrated = 0;
new->ex_layout_types = item->ex_layout_types;
new->ex_nflavors = item->ex_nflavors;
for (i = 0; i < MAX_SECINFO_LIST; i++) {
new->ex_flavors[i] = item->ex_flavors[i];
}
}
static struct cache_head *svc_export_alloc(void)
{
struct svc_export *i = kmalloc(sizeof(*i), GFP_KERNEL);
if (i)
return &i->h;
else
return NULL;
}
static const struct cache_detail svc_export_cache_template = {
.owner = THIS_MODULE,
.hash_size = EXPORT_HASHMAX,
.name = "nfsd.export",
.cache_put = svc_export_put,
.cache_upcall = svc_export_upcall,
.cache_request = svc_export_request,
.cache_parse = svc_export_parse,
.cache_show = svc_export_show,
.match = svc_export_match,
.init = svc_export_init,
.update = export_update,
.alloc = svc_export_alloc,
};
static int
svc_export_hash(struct svc_export *exp)
{
int hash;
hash = hash_ptr(exp->ex_client, EXPORT_HASHBITS);
hash ^= hash_ptr(exp->ex_path.dentry, EXPORT_HASHBITS);
hash ^= hash_ptr(exp->ex_path.mnt, EXPORT_HASHBITS);
return hash;
}
static struct svc_export *
svc_export_lookup(struct svc_export *exp)
{
struct cache_head *ch;
int hash = svc_export_hash(exp);
ch = sunrpc_cache_lookup_rcu(exp->cd, &exp->h, hash);
if (ch)
return container_of(ch, struct svc_export, h);
else
return NULL;
}
static struct svc_export *
svc_export_update(struct svc_export *new, struct svc_export *old)
{
struct cache_head *ch;
int hash = svc_export_hash(old);
ch = sunrpc_cache_update(old->cd, &new->h, &old->h, hash);
if (ch)
return container_of(ch, struct svc_export, h);
else
return NULL;
}
static struct svc_expkey *
exp_find_key(struct cache_detail *cd, struct auth_domain *clp, int fsid_type,
u32 *fsidv, struct cache_req *reqp)
{
struct svc_expkey key, *ek;
int err;
if (!clp)
return ERR_PTR(-ENOENT);
key.ek_client = clp;
key.ek_fsidtype = fsid_type;
memcpy(key.ek_fsid, fsidv, key_len(fsid_type));
ek = svc_expkey_lookup(cd, &key);
if (ek == NULL)
return ERR_PTR(-ENOMEM);
err = cache_check(cd, &ek->h, reqp);
if (err) {
trace_nfsd_exp_find_key(&key, err);
return ERR_PTR(err);
}
return ek;
}
static struct svc_export *
exp_get_by_name(struct cache_detail *cd, struct auth_domain *clp,
const struct path *path, struct cache_req *reqp)
{
struct svc_export *exp, key;
int err;
if (!clp)
return ERR_PTR(-ENOENT);
key.ex_client = clp;
key.ex_path = *path;
key.cd = cd;
exp = svc_export_lookup(&key);
if (exp == NULL)
return ERR_PTR(-ENOMEM);
err = cache_check(cd, &exp->h, reqp);
if (err) {
trace_nfsd_exp_get_by_name(&key, err);
return ERR_PTR(err);
}
return exp;
}
/*
* Find the export entry for a given dentry.
*/
static struct svc_export *
exp_parent(struct cache_detail *cd, struct auth_domain *clp, struct path *path)
{
struct dentry *saved = dget(path->dentry);
struct svc_export *exp = exp_get_by_name(cd, clp, path, NULL);
while (PTR_ERR(exp) == -ENOENT && !IS_ROOT(path->dentry)) {
struct dentry *parent = dget_parent(path->dentry);
dput(path->dentry);
path->dentry = parent;
exp = exp_get_by_name(cd, clp, path, NULL);
}
dput(path->dentry);
path->dentry = saved;
return exp;
}
/*
* Obtain the root fh on behalf of a client.
* This could be done in user space, but I feel that it adds some safety
* since its harder to fool a kernel module than a user space program.
*/
int
exp_rootfh(struct net *net, struct auth_domain *clp, char *name,
struct knfsd_fh *f, int maxsize)
{
struct svc_export *exp;
struct path path;
struct inode *inode;
struct svc_fh fh;
int err;
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
struct cache_detail *cd = nn->svc_export_cache;
err = -EPERM;
/* NB: we probably ought to check that it's NUL-terminated */
if (kern_path(name, 0, &path)) {
printk("nfsd: exp_rootfh path not found %s", name);
return err;
}
inode = d_inode(path.dentry);
dprintk("nfsd: exp_rootfh(%s [%p] %s:%s/%ld)\n",
name, path.dentry, clp->name,
inode->i_sb->s_id, inode->i_ino);
exp = exp_parent(cd, clp, &path);
if (IS_ERR(exp)) {
err = PTR_ERR(exp);
goto out;
}
/*
* fh must be initialized before calling fh_compose
*/
fh_init(&fh, maxsize);
if (fh_compose(&fh, exp, path.dentry, NULL))
err = -EINVAL;
else
err = 0;
memcpy(f, &fh.fh_handle, sizeof(struct knfsd_fh));
fh_put(&fh);
exp_put(exp);
out:
path_put(&path);
return err;
}
static struct svc_export *exp_find(struct cache_detail *cd,
struct auth_domain *clp, int fsid_type,
u32 *fsidv, struct cache_req *reqp)
{
struct svc_export *exp;
struct nfsd_net *nn = net_generic(cd->net, nfsd_net_id);
struct svc_expkey *ek = exp_find_key(nn->svc_expkey_cache, clp, fsid_type, fsidv, reqp);
if (IS_ERR(ek))
return ERR_CAST(ek);
exp = exp_get_by_name(cd, clp, &ek->ek_path, reqp);
cache_put(&ek->h, nn->svc_expkey_cache);
if (IS_ERR(exp))
return ERR_CAST(exp);
return exp;
}
__be32 check_nfsd_access(struct svc_export *exp, struct svc_rqst *rqstp)
{
struct exp_flavor_info *f;
struct exp_flavor_info *end = exp->ex_flavors + exp->ex_nflavors;
/* legacy gss-only clients are always OK: */
if (exp->ex_client == rqstp->rq_gssclient)
return 0;
/* ip-address based client; check sec= export option: */
for (f = exp->ex_flavors; f < end; f++) {
if (f->pseudoflavor == rqstp->rq_cred.cr_flavor)
return 0;
}
/* defaults in absence of sec= options: */
if (exp->ex_nflavors == 0) {
if (rqstp->rq_cred.cr_flavor == RPC_AUTH_NULL ||
rqstp->rq_cred.cr_flavor == RPC_AUTH_UNIX)
return 0;
}
/* If the compound op contains a spo_must_allowed op,
* it will be sent with integrity/protection which
* will have to be expressly allowed on mounts that
* don't support it
*/
if (nfsd4_spo_must_allow(rqstp))
return 0;
return rqstp->rq_vers < 4 ? nfserr_acces : nfserr_wrongsec;
}
/*
* Uses rq_client and rq_gssclient to find an export; uses rq_client (an
* auth_unix client) if it's available and has secinfo information;
* otherwise, will try to use rq_gssclient.
*
* Called from functions that handle requests; functions that do work on
* behalf of mountd are passed a single client name to use, and should
* use exp_get_by_name() or exp_find().
*/
struct svc_export *
rqst_exp_get_by_name(struct svc_rqst *rqstp, struct path *path)
{
struct svc_export *gssexp, *exp = ERR_PTR(-ENOENT);
struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
struct cache_detail *cd = nn->svc_export_cache;
if (rqstp->rq_client == NULL)
goto gss;
/* First try the auth_unix client: */
exp = exp_get_by_name(cd, rqstp->rq_client, path, &rqstp->rq_chandle);
if (PTR_ERR(exp) == -ENOENT)
goto gss;
if (IS_ERR(exp))
return exp;
/* If it has secinfo, assume there are no gss/... clients */
if (exp->ex_nflavors > 0)
return exp;
gss:
/* Otherwise, try falling back on gss client */
if (rqstp->rq_gssclient == NULL)
return exp;
gssexp = exp_get_by_name(cd, rqstp->rq_gssclient, path, &rqstp->rq_chandle);
if (PTR_ERR(gssexp) == -ENOENT)
return exp;
if (!IS_ERR(exp))
exp_put(exp);
return gssexp;
}
struct svc_export *
rqst_exp_find(struct svc_rqst *rqstp, int fsid_type, u32 *fsidv)
{
struct svc_export *gssexp, *exp = ERR_PTR(-ENOENT);
struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
struct cache_detail *cd = nn->svc_export_cache;
if (rqstp->rq_client == NULL)
goto gss;
/* First try the auth_unix client: */
exp = exp_find(cd, rqstp->rq_client, fsid_type,
fsidv, &rqstp->rq_chandle);
if (PTR_ERR(exp) == -ENOENT)
goto gss;
if (IS_ERR(exp))
return exp;
/* If it has secinfo, assume there are no gss/... clients */
if (exp->ex_nflavors > 0)
return exp;
gss:
/* Otherwise, try falling back on gss client */
if (rqstp->rq_gssclient == NULL)
return exp;
gssexp = exp_find(cd, rqstp->rq_gssclient, fsid_type, fsidv,
&rqstp->rq_chandle);
if (PTR_ERR(gssexp) == -ENOENT)
return exp;
if (!IS_ERR(exp))
exp_put(exp);
return gssexp;
}
struct svc_export *
rqst_exp_parent(struct svc_rqst *rqstp, struct path *path)
{
struct dentry *saved = dget(path->dentry);
struct svc_export *exp = rqst_exp_get_by_name(rqstp, path);
while (PTR_ERR(exp) == -ENOENT && !IS_ROOT(path->dentry)) {
struct dentry *parent = dget_parent(path->dentry);
dput(path->dentry);
path->dentry = parent;
exp = rqst_exp_get_by_name(rqstp, path);
}
dput(path->dentry);
path->dentry = saved;
return exp;
}
struct svc_export *rqst_find_fsidzero_export(struct svc_rqst *rqstp)
{
u32 fsidv[2];
mk_fsid(FSID_NUM, fsidv, 0, 0, 0, NULL);
return rqst_exp_find(rqstp, FSID_NUM, fsidv);
}
/*
* Called when we need the filehandle for the root of the pseudofs,
* for a given NFSv4 client. The root is defined to be the
* export point with fsid==0
*/
__be32
exp_pseudoroot(struct svc_rqst *rqstp, struct svc_fh *fhp)
{
struct svc_export *exp;
__be32 rv;
exp = rqst_find_fsidzero_export(rqstp);
if (IS_ERR(exp))
return nfserrno(PTR_ERR(exp));
rv = fh_compose(fhp, exp, exp->ex_path.dentry, NULL);
exp_put(exp);
return rv;
}
static struct flags {
int flag;
char *name[2];
} expflags[] = {
{ NFSEXP_READONLY, {"ro", "rw"}},
{ NFSEXP_INSECURE_PORT, {"insecure", ""}},
{ NFSEXP_ROOTSQUASH, {"root_squash", "no_root_squash"}},
{ NFSEXP_ALLSQUASH, {"all_squash", ""}},
{ NFSEXP_ASYNC, {"async", "sync"}},
{ NFSEXP_GATHERED_WRITES, {"wdelay", "no_wdelay"}},
{ NFSEXP_NOREADDIRPLUS, {"nordirplus", ""}},
{ NFSEXP_NOHIDE, {"nohide", ""}},
{ NFSEXP_CROSSMOUNT, {"crossmnt", ""}},
{ NFSEXP_NOSUBTREECHECK, {"no_subtree_check", ""}},
{ NFSEXP_NOAUTHNLM, {"insecure_locks", ""}},
{ NFSEXP_V4ROOT, {"v4root", ""}},
{ NFSEXP_PNFS, {"pnfs", ""}},
{ NFSEXP_SECURITY_LABEL, {"security_label", ""}},
{ 0, {"", ""}}
};
static void show_expflags(struct seq_file *m, int flags, int mask)
{
struct flags *flg;
int state, first = 0;
for (flg = expflags; flg->flag; flg++) {
if (flg->flag & ~mask)
continue;
state = (flg->flag & flags) ? 0 : 1;
if (*flg->name[state])
seq_printf(m, "%s%s", first++?",":"", flg->name[state]);
}
}
static void show_secinfo_flags(struct seq_file *m, int flags)
{
seq_printf(m, ",");
show_expflags(m, flags, NFSEXP_SECINFO_FLAGS);
}
static bool secinfo_flags_equal(int f, int g)
{
f &= NFSEXP_SECINFO_FLAGS;
g &= NFSEXP_SECINFO_FLAGS;
return f == g;
}
static int show_secinfo_run(struct seq_file *m, struct exp_flavor_info **fp, struct exp_flavor_info *end)
{
int flags;
flags = (*fp)->flags;
seq_printf(m, ",sec=%d", (*fp)->pseudoflavor);
(*fp)++;
while (*fp != end && secinfo_flags_equal(flags, (*fp)->flags)) {
seq_printf(m, ":%d", (*fp)->pseudoflavor);
(*fp)++;
}
return flags;
}
static void show_secinfo(struct seq_file *m, struct svc_export *exp)
{
struct exp_flavor_info *f;
struct exp_flavor_info *end = exp->ex_flavors + exp->ex_nflavors;
int flags;
if (exp->ex_nflavors == 0)
return;
f = exp->ex_flavors;
flags = show_secinfo_run(m, &f, end);
if (!secinfo_flags_equal(flags, exp->ex_flags))
show_secinfo_flags(m, flags);
while (f != end) {
flags = show_secinfo_run(m, &f, end);
show_secinfo_flags(m, flags);
}
}
static void exp_flags(struct seq_file *m, int flag, int fsid,
kuid_t anonu, kgid_t anong, struct nfsd4_fs_locations *fsloc)
{
struct user_namespace *userns = m->file->f_cred->user_ns;
show_expflags(m, flag, NFSEXP_ALLFLAGS);
if (flag & NFSEXP_FSID)
seq_printf(m, ",fsid=%d", fsid);
if (!uid_eq(anonu, make_kuid(userns, (uid_t)-2)) &&
!uid_eq(anonu, make_kuid(userns, 0x10000-2)))
seq_printf(m, ",anonuid=%u", from_kuid_munged(userns, anonu));
if (!gid_eq(anong, make_kgid(userns, (gid_t)-2)) &&
!gid_eq(anong, make_kgid(userns, 0x10000-2)))
seq_printf(m, ",anongid=%u", from_kgid_munged(userns, anong));
if (fsloc && fsloc->locations_count > 0) {
char *loctype = (fsloc->migrated) ? "refer" : "replicas";
int i;
seq_printf(m, ",%s=", loctype);
seq_escape(m, fsloc->locations[0].path, ",;@ \t\n\\");
seq_putc(m, '@');
seq_escape(m, fsloc->locations[0].hosts, ",;@ \t\n\\");
for (i = 1; i < fsloc->locations_count; i++) {
seq_putc(m, ';');
seq_escape(m, fsloc->locations[i].path, ",;@ \t\n\\");
seq_putc(m, '@');
seq_escape(m, fsloc->locations[i].hosts, ",;@ \t\n\\");
}
}
}
static int e_show(struct seq_file *m, void *p)
{
struct cache_head *cp = p;
struct svc_export *exp = container_of(cp, struct svc_export, h);
struct cache_detail *cd = m->private;
if (p == SEQ_START_TOKEN) {
seq_puts(m, "# Version 1.1\n");
seq_puts(m, "# Path Client(Flags) # IPs\n");
return 0;
}
exp_get(exp);
if (cache_check(cd, &exp->h, NULL))
return 0;
exp_put(exp);
return svc_export_show(m, cd, cp);
}
const struct seq_operations nfs_exports_op = {
.start = cache_seq_start_rcu,
.next = cache_seq_next_rcu,
.stop = cache_seq_stop_rcu,
.show = e_show,
};
/*
* Initialize the exports module.
*/
int
nfsd_export_init(struct net *net)
{
int rv;
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
dprintk("nfsd: initializing export module (net: %x).\n", net->ns.inum);
nn->svc_export_cache = cache_create_net(&svc_export_cache_template, net);
if (IS_ERR(nn->svc_export_cache))
return PTR_ERR(nn->svc_export_cache);
rv = cache_register_net(nn->svc_export_cache, net);
if (rv)
goto destroy_export_cache;
nn->svc_expkey_cache = cache_create_net(&svc_expkey_cache_template, net);
if (IS_ERR(nn->svc_expkey_cache)) {
rv = PTR_ERR(nn->svc_expkey_cache);
goto unregister_export_cache;
}
rv = cache_register_net(nn->svc_expkey_cache, net);
if (rv)
goto destroy_expkey_cache;
return 0;
destroy_expkey_cache:
cache_destroy_net(nn->svc_expkey_cache, net);
unregister_export_cache:
cache_unregister_net(nn->svc_export_cache, net);
destroy_export_cache:
cache_destroy_net(nn->svc_export_cache, net);
return rv;
}
/*
* Flush exports table - called when last nfsd thread is killed
*/
void
nfsd_export_flush(struct net *net)
{
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
cache_purge(nn->svc_expkey_cache);
cache_purge(nn->svc_export_cache);
}
/*
* Shutdown the exports module.
*/
void
nfsd_export_shutdown(struct net *net)
{
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
dprintk("nfsd: shutting down export module (net: %x).\n", net->ns.inum);
cache_unregister_net(nn->svc_expkey_cache, net);
cache_unregister_net(nn->svc_export_cache, net);
cache_destroy_net(nn->svc_expkey_cache, net);
cache_destroy_net(nn->svc_export_cache, net);
svcauth_unix_purge(net);
dprintk("nfsd: export shutdown complete (net: %x).\n", net->ns.inum);
}
Ссылка в новой задаче Показать git blame Копировать постоянную ссылку