linux/fs/nfsd/export.c
Linus Torvalds b6669737d3 Merge branch 'for-3.9' of git://linux-nfs.org/~bfields/linux
Pull nfsd changes from J Bruce Fields:
 "Miscellaneous bugfixes, plus:

   - An overhaul of the DRC cache by Jeff Layton.  The main effect is
     just to make it larger.  This decreases the chances of intermittent
     errors especially in the UDP case.  But we'll need to watch for any
     reports of performance regressions.

   - Containerized nfsd: with some limitations, we now support
     per-container nfs-service, thanks to extensive work from Stanislav
     Kinsbursky over the last year."

Some notes about conflicts, since there were *two* non-data semantic
conflicts here:

 - idr_remove_all() had been added by a memory leak fix, but has since
   become deprecated since idr_destroy() does it for us now.

 - xs_local_connect() had been added by this branch to make AF_LOCAL
   connections be synchronous, but in the meantime Trond had changed the
   calling convention in order to avoid a RCU dereference.

There were a couple of more obvious actual source-level conflicts due to
the hlist traversal changes and one just due to code changes next to
each other, but those were trivial.

* 'for-3.9' of git://linux-nfs.org/~bfields/linux: (49 commits)
  SUNRPC: make AF_LOCAL connect synchronous
  nfsd: fix compiler warning about ambiguous types in nfsd_cache_csum
  svcrpc: fix rpc server shutdown races
  svcrpc: make svc_age_temp_xprts enqueue under sv_lock
  lockd: nlmclnt_reclaim(): avoid stack overflow
  nfsd: enable NFSv4 state in containers
  nfsd: disable usermode helper client tracker in container
  nfsd: use proper net while reading "exports" file
  nfsd: containerize NFSd filesystem
  nfsd: fix comments on nfsd_cache_lookup
  SUNRPC: move cache_detail->cache_request callback call to cache_read()
  SUNRPC: remove "cache_request" argument in sunrpc_cache_pipe_upcall() function
  SUNRPC: rework cache upcall logic
  SUNRPC: introduce cache_detail->cache_request callback
  NFS: simplify and clean cache library
  NFS: use SUNRPC cache creation and destruction helper for DNS cache
  nfsd4: free_stid can be static
  nfsd: keep a checksum of the first 256 bytes of request
  sunrpc: trim off trailing checksum before returning decrypted or integrity authenticated buffer
  sunrpc: fix comment in struct xdr_buf definition
  ...
2013-02-28 18:02:55 -08:00

1299 lines
32 KiB
C

/*
* 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 <net/ipv6.h>
#include "nfsd.h"
#include "nfsfh.h"
#include "netns.h"
#define NFSDDBG_FACILITY NFSDDBG_EXPORT
typedef struct auth_domain svc_client;
typedef struct svc_export svc_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(key);
}
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 [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)
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)
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 struct cache_detail svc_expkey_cache_template = {
.owner = THIS_MODULE,
.hash_size = EXPKEY_HASHMAX,
.name = "nfsd.fh",
.cache_put = expkey_put,
.cache_request = expkey_request,
.cache_parse = expkey_parse,
.cache_show = expkey_show,
.match = expkey_match,
.init = expkey_init,
.update = expkey_update,
.alloc = expkey_alloc,
};
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(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)
{
int i;
for (i = 0; i < fsloc->locations_count; i++) {
kfree(fsloc->locations[i].path);
kfree(fsloc->locations[i].hosts);
}
kfree(fsloc->locations);
}
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(exp);
}
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;
}
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;
/* 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 = kzalloc(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)
{
int listsize, err;
struct exp_flavor_info *f;
err = get_int(mesg, &listsize);
if (err)
return err;
if (listsize < 0 || 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 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;
/* 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(&init_user_ns, an_int);
if (!uid_valid(exp.ex_anon_uid))
goto out3;
/* anon gid */
err = get_int(&mesg, &an_int);
if (err)
goto out3;
exp.ex_anon_gid= make_kgid(&init_user_ns, an_int);
if (!gid_valid(exp.ex_anon_gid))
goto out3;
/* 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) {
/* expect a 16 byte uuid encoded as \xXXXX... */
len = qword_get(&mesg, buf, PAGE_SIZE);
if (len != 16)
err = -EINVAL;
else {
exp.ex_uuid =
kmemdup(buf, 16, GFP_KERNEL);
if (exp.ex_uuid == NULL)
err = -ENOMEM;
}
} 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(exp.ex_path.dentry->d_inode, &exp.ex_flags,
exp.ex_uuid);
if (err)
goto out4;
}
expp = svc_export_lookup(&exp);
if (expp)
expp = svc_export_update(&exp, expp);
else
err = -ENOMEM;
cache_flush();
if (expp == NULL)
err = -ENOMEM;
else
exp_put(expp);
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<16; 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 &&
orig->ex_path.dentry == new->ex_path.dentry &&
orig->ex_path.mnt == new->ex_path.mnt;
}
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.dentry = dget(item->ex_path.dentry);
new->ex_path.mnt = mntget(item->ex_path.mnt);
new->ex_fslocs.locations = NULL;
new->ex_fslocs.locations_count = 0;
new->ex_fslocs.migrated = 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_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_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 struct cache_detail svc_export_cache_template = {
.owner = THIS_MODULE,
.hash_size = EXPORT_HASHMAX,
.name = "nfsd.export",
.cache_put = svc_export_put,
.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(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, svc_client *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)
return ERR_PTR(err);
return ek;
}
static svc_export *exp_get_by_name(struct cache_detail *cd, svc_client *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)
return ERR_PTR(err);
return exp;
}
/*
* Find the export entry for a given dentry.
*/
static struct svc_export *exp_parent(struct cache_detail *cd, svc_client *clp,
struct path *path)
{
struct dentry *saved = dget(path->dentry);
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, svc_client *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 = path.dentry->d_inode;
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;
}
return 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;
}
/* Iterator */
static void *e_start(struct seq_file *m, loff_t *pos)
__acquires(((struct cache_detail *)m->private)->hash_lock)
{
loff_t n = *pos;
unsigned hash, export;
struct cache_head *ch;
struct cache_detail *cd = m->private;
struct cache_head **export_table = cd->hash_table;
read_lock(&cd->hash_lock);
if (!n--)
return SEQ_START_TOKEN;
hash = n >> 32;
export = n & ((1LL<<32) - 1);
for (ch=export_table[hash]; ch; ch=ch->next)
if (!export--)
return ch;
n &= ~((1LL<<32) - 1);
do {
hash++;
n += 1LL<<32;
} while(hash < EXPORT_HASHMAX && export_table[hash]==NULL);
if (hash >= EXPORT_HASHMAX)
return NULL;
*pos = n+1;
return export_table[hash];
}
static void *e_next(struct seq_file *m, void *p, loff_t *pos)
{
struct cache_head *ch = p;
int hash = (*pos >> 32);
struct cache_detail *cd = m->private;
struct cache_head **export_table = cd->hash_table;
if (p == SEQ_START_TOKEN)
hash = 0;
else if (ch->next == NULL) {
hash++;
*pos += 1LL<<32;
} else {
++*pos;
return ch->next;
}
*pos &= ~((1LL<<32) - 1);
while (hash < EXPORT_HASHMAX && export_table[hash] == NULL) {
hash++;
*pos += 1LL<<32;
}
if (hash >= EXPORT_HASHMAX)
return NULL;
++*pos;
return export_table[hash];
}
static void e_stop(struct seq_file *m, void *p)
__releases(((struct cache_detail *)m->private)->hash_lock)
{
struct cache_detail *cd = m->private;
read_unlock(&cd->hash_lock);
}
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_NOHIDE, {"nohide", ""}},
{ NFSEXP_CROSSMOUNT, {"crossmnt", ""}},
{ NFSEXP_NOSUBTREECHECK, {"no_subtree_check", ""}},
{ NFSEXP_NOAUTHNLM, {"insecure_locks", ""}},
{ NFSEXP_V4ROOT, {"v4root", ""}},
{ 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)
{
show_expflags(m, flag, NFSEXP_ALLFLAGS);
if (flag & NFSEXP_FSID)
seq_printf(m, ",fsid=%d", fsid);
if (!uid_eq(anonu, make_kuid(&init_user_ns, (uid_t)-2)) &&
!uid_eq(anonu, make_kuid(&init_user_ns, 0x10000-2)))
seq_printf(m, ",anonuid=%u", from_kuid(&init_user_ns, anonu));
if (!gid_eq(anong, make_kgid(&init_user_ns, (gid_t)-2)) &&
!gid_eq(anong, make_kgid(&init_user_ns, 0x10000-2)))
seq_printf(m, ",anongid=%u", from_kgid(&init_user_ns, 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;
}
cache_get(&exp->h);
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 = e_start,
.next = e_next,
.stop = e_stop,
.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: %p).\n", net);
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: %p).\n", net);
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: %p).\n", net);
}