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[PATCH] knfsd: nfsd4: reboot hash
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For the purposes of reboot recovery we keep a directory with subdirectories
each having a name that is the ascii hex representation of the md5 sum of a
client identifier for an active client.

This adds the code to calculate that name.  We also use it for the purposes of
comparing clients, so if someone ever manages to find two client names that
are md5 collisions, then we'll return clid_inuse to the second.

Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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NeilBrown authored and Linus Torvalds committed Jun 24, 2005
1 parent 7dea9d2 commit a55370a
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Showing 5 changed files with 143 additions and 44 deletions.
2 changes: 2 additions & 0 deletions fs/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -1413,6 +1413,8 @@ config NFSD_V4
bool "Provide NFSv4 server support (EXPERIMENTAL)"
depends on NFSD_V3 && EXPERIMENTAL
select NFSD_TCP
select CRYPTO_MD5
select CRYPTO
help
If you would like to include the NFSv4 server as well as the NFSv2
and NFSv3 servers, say Y here. This feature is experimental, and
Expand Down
2 changes: 1 addition & 1 deletion fs/nfsd/Makefile
Original file line number Diff line number Diff line change
Expand Up @@ -10,5 +10,5 @@ nfsd-$(CONFIG_NFSD_V2_ACL) += nfs2acl.o
nfsd-$(CONFIG_NFSD_V3) += nfs3proc.o nfs3xdr.o
nfsd-$(CONFIG_NFSD_V3_ACL) += nfs3acl.o
nfsd-$(CONFIG_NFSD_V4) += nfs4proc.o nfs4xdr.o nfs4state.o nfs4idmap.o \
nfs4acl.o nfs4callback.o
nfs4acl.o nfs4callback.o nfs4recover.o
nfsd-objs := $(nfsd-y)
97 changes: 97 additions & 0 deletions fs/nfsd/nfs4recover.c
Original file line number Diff line number Diff line change
@@ -0,0 +1,97 @@
/*
* linux/fs/nfsd/nfs4recover.c
*
* Copyright (c) 2004 The Regents of the University of Michigan.
* All rights reserved.
*
* Andy Adamson <andros@citi.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/sunrpc/svc.h>
#include <linux/nfsd/nfsd.h>
#include <linux/nfs4.h>
#include <linux/nfsd/state.h>
#include <linux/nfsd/xdr4.h>
#include <asm/uaccess.h>
#include <asm/scatterlist.h>
#include <linux/crypto.h>


#define NFSDDBG_FACILITY NFSDDBG_PROC

static void
md5_to_hex(char *out, char *md5)
{
int i;

for (i=0; i<16; i++) {
unsigned char c = md5[i];

*out++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)*('a'-'9'-1);
*out++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)*('a'-'9'-1);
}
*out = '\0';
}

int
nfs4_make_rec_clidname(char *dname, struct xdr_netobj *clname)
{
struct xdr_netobj cksum;
struct crypto_tfm *tfm;
struct scatterlist sg[1];
int status = nfserr_resource;

dprintk("NFSD: nfs4_make_rec_clidname for %.*s\n",
clname->len, clname->data);
tfm = crypto_alloc_tfm("md5", 0);
if (tfm == NULL)
goto out;
cksum.len = crypto_tfm_alg_digestsize(tfm);
cksum.data = kmalloc(cksum.len, GFP_KERNEL);
if (cksum.data == NULL)
goto out;
crypto_digest_init(tfm);

sg[0].page = virt_to_page(clname->data);
sg[0].offset = offset_in_page(clname->data);
sg[0].length = clname->len;

crypto_digest_update(tfm, sg, 1);
crypto_digest_final(tfm, cksum.data);

md5_to_hex(dname, cksum.data);

kfree(cksum.data);
status = nfs_ok;
out:
if (tfm)
crypto_free_tfm(tfm);
return status;
}
80 changes: 38 additions & 42 deletions fs/nfsd/nfs4state.c
Original file line number Diff line number Diff line change
Expand Up @@ -231,8 +231,8 @@ unhash_delegation(struct nfs4_delegation *dp)

#define clientid_hashval(id) \
((id) & CLIENT_HASH_MASK)
#define clientstr_hashval(name, namelen) \
(opaque_hashval((name), (namelen)) & CLIENT_HASH_MASK)
#define clientstr_hashval(name) \
(opaque_hashval((name), 8) & CLIENT_HASH_MASK)
/*
* reclaim_str_hashtbl[] holds known client info from previous reset/reboot
* used in reboot/reset lease grace period processing
Expand Down Expand Up @@ -366,11 +366,12 @@ expire_client(struct nfs4_client *clp)
}

static struct nfs4_client *
create_client(struct xdr_netobj name) {
create_client(struct xdr_netobj name, char *recdir) {
struct nfs4_client *clp;

if (!(clp = alloc_client(name)))
goto out;
memcpy(clp->cl_recdir, recdir, HEXDIR_LEN);
atomic_set(&clp->cl_count, 1);
atomic_set(&clp->cl_callback.cb_set, 0);
clp->cl_callback.cb_parsed = 0;
Expand Down Expand Up @@ -403,11 +404,9 @@ copy_cred(struct svc_cred *target, struct svc_cred *source) {
get_group_info(target->cr_group_info);
}

static int
cmp_name(struct xdr_netobj *n1, struct xdr_netobj *n2) {
if (!n1 || !n2)
return 0;
return((n1->len == n2->len) && !memcmp(n1->data, n2->data, n2->len));
static inline int
same_name(const char *n1, const char *n2) {
return 0 == memcmp(n1, n2, HEXDIR_LEN);
}

static int
Expand Down Expand Up @@ -479,8 +478,7 @@ move_to_confirmed(struct nfs4_client *clp)
list_del_init(&clp->cl_strhash);
list_del_init(&clp->cl_idhash);
list_add(&clp->cl_idhash, &conf_id_hashtbl[idhashval]);
strhashval = clientstr_hashval(clp->cl_name.data,
clp->cl_name.len);
strhashval = clientstr_hashval(clp->cl_recdir);
list_add(&clp->cl_strhash, &conf_str_hashtbl[strhashval]);
renew_client(clp);
}
Expand Down Expand Up @@ -651,22 +649,27 @@ nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_setclientid *setclid)
unsigned int strhashval;
struct nfs4_client * conf, * unconf, * new, * clp;
int status;
char dname[HEXDIR_LEN];

status = nfserr_inval;
if (!check_name(clname))
goto out;

status = nfs4_make_rec_clidname(dname, &clname);
if (status)
goto out;

/*
* XXX The Duplicate Request Cache (DRC) has been checked (??)
* We get here on a DRC miss.
*/

strhashval = clientstr_hashval(clname.data, clname.len);
strhashval = clientstr_hashval(dname);

conf = NULL;
nfs4_lock_state();
list_for_each_entry(clp, &conf_str_hashtbl[strhashval], cl_strhash) {
if (!cmp_name(&clp->cl_name, &clname))
if (!same_name(clp->cl_recdir, dname))
continue;
/*
* CASE 0:
Expand All @@ -686,7 +689,7 @@ nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_setclientid *setclid)
}
unconf = NULL;
list_for_each_entry(clp, &unconf_str_hashtbl[strhashval], cl_strhash) {
if (!cmp_name(&clp->cl_name, &clname))
if (!same_name(clp->cl_recdir, dname))
continue;
/* cl_name match from a previous SETCLIENTID operation */
unconf = clp;
Expand All @@ -700,7 +703,8 @@ nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_setclientid *setclid)
*/
if (unconf)
expire_client(unconf);
if (!(new = create_client(clname)))
new = create_client(clname, dname);
if (new == NULL)
goto out;
copy_verf(new, &clverifier);
new->cl_addr = ip_addr;
Expand Down Expand Up @@ -728,7 +732,8 @@ nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_setclientid *setclid)
cmp_clid(&unconf->cl_clientid, &conf->cl_clientid)) {
expire_client(unconf);
}
if (!(new = create_client(clname)))
new = create_client(clname, dname);
if (new == NULL)
goto out;
copy_verf(new,&conf->cl_verifier);
new->cl_addr = ip_addr;
Expand All @@ -746,7 +751,8 @@ nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_setclientid *setclid)
* using input clverifier, clname, and callback info
* and generate a new cl_clientid and cl_confirm.
*/
if (!(new = create_client(clname)))
new = create_client(clname, dname);
if (new == NULL)
goto out;
copy_verf(new,&clverifier);
new->cl_addr = ip_addr;
Expand All @@ -772,7 +778,8 @@ nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_setclientid *setclid)
* new cl_verifier and a new cl_confirm
*/
expire_client(unconf);
if (!(new = create_client(clname)))
new = create_client(clname, dname);
if (new == NULL)
goto out;
copy_verf(new,&clverifier);
new->cl_addr = ip_addr;
Expand Down Expand Up @@ -856,7 +863,7 @@ nfsd4_setclientid_confirm(struct svc_rqst *rqstp, struct nfsd4_setclientid_confi
if ((conf && unconf) &&
(cmp_verf(&unconf->cl_confirm, &confirm)) &&
(cmp_verf(&conf->cl_verifier, &unconf->cl_verifier)) &&
(cmp_name(&conf->cl_name,&unconf->cl_name)) &&
(same_name(conf->cl_recdir,unconf->cl_recdir)) &&
(!cmp_verf(&conf->cl_confirm, &unconf->cl_confirm))) {
if (!cmp_creds(&conf->cl_cred, &unconf->cl_cred))
status = nfserr_clid_inuse;
Expand All @@ -876,7 +883,7 @@ nfsd4_setclientid_confirm(struct svc_rqst *rqstp, struct nfsd4_setclientid_confi
if ((conf && !unconf) ||
((conf && unconf) &&
(!cmp_verf(&conf->cl_verifier, &unconf->cl_verifier) ||
!cmp_name(&conf->cl_name, &unconf->cl_name)))) {
!same_name(conf->cl_recdir, unconf->cl_recdir)))) {
if (!cmp_creds(&conf->cl_cred,&rqstp->rq_cred)) {
status = nfserr_clid_inuse;
} else {
Expand Down Expand Up @@ -3074,39 +3081,28 @@ nfsd4_release_lockowner(struct svc_rqst *rqstp, struct nfsd4_release_lockowner *
}

static inline struct nfs4_client_reclaim *
alloc_reclaim(int namelen)
alloc_reclaim(void)
{
struct nfs4_client_reclaim *crp = NULL;

crp = kmalloc(sizeof(struct nfs4_client_reclaim), GFP_KERNEL);
if (!crp)
return NULL;
crp->cr_name.data = kmalloc(namelen, GFP_KERNEL);
if (!crp->cr_name.data) {
kfree(crp);
return NULL;
}
return crp;
return kmalloc(sizeof(struct nfs4_client_reclaim), GFP_KERNEL);
}

/*
* failure => all reset bets are off, nfserr_no_grace...
*/
static int
nfs4_client_to_reclaim(char *name, int namlen)
nfs4_client_to_reclaim(char *name)
{
unsigned int strhashval;
struct nfs4_client_reclaim *crp = NULL;

dprintk("NFSD nfs4_client_to_reclaim NAME: %.*s\n", namlen, name);
crp = alloc_reclaim(namlen);
dprintk("NFSD nfs4_client_to_reclaim NAME: %.*s\n", HEXDIR_LEN, name);
crp = alloc_reclaim();
if (!crp)
return 0;
strhashval = clientstr_hashval(name, namlen);
strhashval = clientstr_hashval(name);
INIT_LIST_HEAD(&crp->cr_strhash);
list_add(&crp->cr_strhash, &reclaim_str_hashtbl[strhashval]);
memcpy(crp->cr_name.data, name, namlen);
crp->cr_name.len = namlen;
memcpy(crp->cr_recdir, name, HEXDIR_LEN);
reclaim_str_hashtbl_size++;
return 1;
}
Expand All @@ -3122,7 +3118,6 @@ nfs4_release_reclaim(void)
crp = list_entry(reclaim_str_hashtbl[i].next,
struct nfs4_client_reclaim, cr_strhash);
list_del(&crp->cr_strhash);
kfree(crp->cr_name.data);
kfree(crp);
reclaim_str_hashtbl_size--;
}
Expand All @@ -3145,13 +3140,14 @@ nfs4_find_reclaim_client(clientid_t *clid)
if (clp == NULL)
return NULL;

dprintk("NFSD: nfs4_find_reclaim_client for %.*s\n",
clp->cl_name.len, clp->cl_name.data);
dprintk("NFSD: nfs4_find_reclaim_client for %.*s with recdir %s\n",
clp->cl_name.len, clp->cl_name.data,
clp->cl_recdir);

/* find clp->cl_name in reclaim_str_hashtbl */
strhashval = clientstr_hashval(clp->cl_name.data, clp->cl_name.len);
strhashval = clientstr_hashval(clp->cl_recdir);
list_for_each_entry(crp, &reclaim_str_hashtbl[strhashval], cr_strhash) {
if (cmp_name(&crp->cr_name, &clp->cl_name)) {
if (same_name(crp->cr_recdir, clp->cl_recdir)) {
return crp;
}
}
Expand Down
6 changes: 5 additions & 1 deletion include/linux/nfsd/state.h
Original file line number Diff line number Diff line change
Expand Up @@ -109,6 +109,8 @@ struct nfs4_callback {
struct rpc_clnt * cb_client;
};

#define HEXDIR_LEN 33 /* hex version of 16 byte md5 of cl_name plus '\0' */

/*
* struct nfs4_client - one per client. Clientids live here.
* o Each nfs4_client is hashed by clientid.
Expand All @@ -126,6 +128,7 @@ struct nfs4_client {
struct list_head cl_del_perclnt; /* list: delegations */
struct list_head cl_lru; /* tail queue */
struct xdr_netobj cl_name; /* id generated by client */
char cl_recdir[HEXDIR_LEN]; /* recovery dir */
nfs4_verifier cl_verifier; /* generated by client */
time_t cl_time; /* time of last lease renewal */
u32 cl_addr; /* client ipaddress */
Expand All @@ -143,7 +146,7 @@ struct nfs4_client {
*/
struct nfs4_client_reclaim {
struct list_head cr_strhash; /* hash by cr_name */
struct xdr_netobj cr_name; /* id generated by client */
char cr_recdir[HEXDIR_LEN]; /* recover dir */
};

static inline void
Expand Down Expand Up @@ -283,6 +286,7 @@ extern void nfs4_free_stateowner(struct kref *kref);
extern void nfsd4_probe_callback(struct nfs4_client *clp);
extern void nfsd4_cb_recall(struct nfs4_delegation *dp);
extern void nfs4_put_delegation(struct nfs4_delegation *dp);
extern int nfs4_make_rec_clidname(char *clidname, struct xdr_netobj *clname);

static inline void
nfs4_put_stateowner(struct nfs4_stateowner *so)
Expand Down

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