| /* |
| * 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/err.h> |
| #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 <linux/param.h> |
| #include <linux/file.h> |
| #include <linux/namei.h> |
| #include <asm/uaccess.h> |
| #include <asm/scatterlist.h> |
| #include <linux/crypto.h> |
| #include <linux/sched.h> |
| |
| #define NFSDDBG_FACILITY NFSDDBG_PROC |
| |
| /* Globals */ |
| static struct nameidata rec_dir; |
| static int rec_dir_init = 0; |
| |
| static void |
| nfs4_save_user(uid_t *saveuid, gid_t *savegid) |
| { |
| *saveuid = current->fsuid; |
| *savegid = current->fsgid; |
| current->fsuid = 0; |
| current->fsgid = 0; |
| } |
| |
| static void |
| nfs4_reset_user(uid_t saveuid, gid_t savegid) |
| { |
| current->fsuid = saveuid; |
| current->fsgid = savegid; |
| } |
| |
| 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'; |
| } |
| |
| __be32 |
| nfs4_make_rec_clidname(char *dname, struct xdr_netobj *clname) |
| { |
| struct xdr_netobj cksum; |
| struct hash_desc desc; |
| struct scatterlist sg; |
| __be32 status = nfserr_resource; |
| |
| dprintk("NFSD: nfs4_make_rec_clidname for %.*s\n", |
| clname->len, clname->data); |
| desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; |
| desc.tfm = crypto_alloc_hash("md5", 0, CRYPTO_ALG_ASYNC); |
| if (IS_ERR(desc.tfm)) |
| goto out_no_tfm; |
| cksum.len = crypto_hash_digestsize(desc.tfm); |
| cksum.data = kmalloc(cksum.len, GFP_KERNEL); |
| if (cksum.data == NULL) |
| goto out; |
| |
| sg_init_one(&sg, clname->data, clname->len); |
| |
| if (crypto_hash_digest(&desc, &sg, sg.length, cksum.data)) |
| goto out; |
| |
| md5_to_hex(dname, cksum.data); |
| |
| kfree(cksum.data); |
| status = nfs_ok; |
| out: |
| crypto_free_hash(desc.tfm); |
| out_no_tfm: |
| return status; |
| } |
| |
| static void |
| nfsd4_sync_rec_dir(void) |
| { |
| mutex_lock(&rec_dir.dentry->d_inode->i_mutex); |
| nfsd_sync_dir(rec_dir.dentry); |
| mutex_unlock(&rec_dir.dentry->d_inode->i_mutex); |
| } |
| |
| int |
| nfsd4_create_clid_dir(struct nfs4_client *clp) |
| { |
| char *dname = clp->cl_recdir; |
| struct dentry *dentry; |
| uid_t uid; |
| gid_t gid; |
| int status; |
| |
| dprintk("NFSD: nfsd4_create_clid_dir for \"%s\"\n", dname); |
| |
| if (!rec_dir_init || clp->cl_firststate) |
| return 0; |
| |
| nfs4_save_user(&uid, &gid); |
| |
| /* lock the parent */ |
| mutex_lock(&rec_dir.dentry->d_inode->i_mutex); |
| |
| dentry = lookup_one_len(dname, rec_dir.dentry, HEXDIR_LEN-1); |
| if (IS_ERR(dentry)) { |
| status = PTR_ERR(dentry); |
| goto out_unlock; |
| } |
| status = -EEXIST; |
| if (dentry->d_inode) { |
| dprintk("NFSD: nfsd4_create_clid_dir: DIRECTORY EXISTS\n"); |
| goto out_put; |
| } |
| status = vfs_mkdir(rec_dir.dentry->d_inode, dentry, S_IRWXU); |
| out_put: |
| dput(dentry); |
| out_unlock: |
| mutex_unlock(&rec_dir.dentry->d_inode->i_mutex); |
| if (status == 0) { |
| clp->cl_firststate = 1; |
| nfsd4_sync_rec_dir(); |
| } |
| nfs4_reset_user(uid, gid); |
| dprintk("NFSD: nfsd4_create_clid_dir returns %d\n", status); |
| return status; |
| } |
| |
| typedef int (recdir_func)(struct dentry *, struct dentry *); |
| |
| struct dentry_list { |
| struct dentry *dentry; |
| struct list_head list; |
| }; |
| |
| struct dentry_list_arg { |
| struct list_head dentries; |
| struct dentry *parent; |
| }; |
| |
| static int |
| nfsd4_build_dentrylist(void *arg, const char *name, int namlen, |
| loff_t offset, u64 ino, unsigned int d_type) |
| { |
| struct dentry_list_arg *dla = arg; |
| struct list_head *dentries = &dla->dentries; |
| struct dentry *parent = dla->parent; |
| struct dentry *dentry; |
| struct dentry_list *child; |
| |
| if (name && isdotent(name, namlen)) |
| return 0; |
| dentry = lookup_one_len(name, parent, namlen); |
| if (IS_ERR(dentry)) |
| return PTR_ERR(dentry); |
| child = kmalloc(sizeof(*child), GFP_KERNEL); |
| if (child == NULL) |
| return -ENOMEM; |
| child->dentry = dentry; |
| list_add(&child->list, dentries); |
| return 0; |
| } |
| |
| static int |
| nfsd4_list_rec_dir(struct dentry *dir, recdir_func *f) |
| { |
| struct file *filp; |
| struct dentry_list_arg dla = { |
| .parent = dir, |
| }; |
| struct list_head *dentries = &dla.dentries; |
| struct dentry_list *child; |
| uid_t uid; |
| gid_t gid; |
| int status; |
| |
| if (!rec_dir_init) |
| return 0; |
| |
| nfs4_save_user(&uid, &gid); |
| |
| filp = dentry_open(dget(dir), mntget(rec_dir.mnt), O_RDONLY); |
| status = PTR_ERR(filp); |
| if (IS_ERR(filp)) |
| goto out; |
| INIT_LIST_HEAD(dentries); |
| status = vfs_readdir(filp, nfsd4_build_dentrylist, &dla); |
| fput(filp); |
| while (!list_empty(dentries)) { |
| child = list_entry(dentries->next, struct dentry_list, list); |
| status = f(dir, child->dentry); |
| if (status) |
| goto out; |
| list_del(&child->list); |
| dput(child->dentry); |
| kfree(child); |
| } |
| out: |
| while (!list_empty(dentries)) { |
| child = list_entry(dentries->next, struct dentry_list, list); |
| list_del(&child->list); |
| dput(child->dentry); |
| kfree(child); |
| } |
| nfs4_reset_user(uid, gid); |
| return status; |
| } |
| |
| static int |
| nfsd4_remove_clid_file(struct dentry *dir, struct dentry *dentry) |
| { |
| int status; |
| |
| if (!S_ISREG(dir->d_inode->i_mode)) { |
| printk("nfsd4: non-file found in client recovery directory\n"); |
| return -EINVAL; |
| } |
| mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT); |
| status = vfs_unlink(dir->d_inode, dentry); |
| mutex_unlock(&dir->d_inode->i_mutex); |
| return status; |
| } |
| |
| static int |
| nfsd4_clear_clid_dir(struct dentry *dir, struct dentry *dentry) |
| { |
| int status; |
| |
| /* For now this directory should already be empty, but we empty it of |
| * any regular files anyway, just in case the directory was created by |
| * a kernel from the future.... */ |
| nfsd4_list_rec_dir(dentry, nfsd4_remove_clid_file); |
| mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT); |
| status = vfs_rmdir(dir->d_inode, dentry); |
| mutex_unlock(&dir->d_inode->i_mutex); |
| return status; |
| } |
| |
| static int |
| nfsd4_unlink_clid_dir(char *name, int namlen) |
| { |
| struct dentry *dentry; |
| int status; |
| |
| dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name); |
| |
| mutex_lock(&rec_dir.dentry->d_inode->i_mutex); |
| dentry = lookup_one_len(name, rec_dir.dentry, namlen); |
| mutex_unlock(&rec_dir.dentry->d_inode->i_mutex); |
| if (IS_ERR(dentry)) { |
| status = PTR_ERR(dentry); |
| return status; |
| } |
| status = -ENOENT; |
| if (!dentry->d_inode) |
| goto out; |
| |
| status = nfsd4_clear_clid_dir(rec_dir.dentry, dentry); |
| out: |
| dput(dentry); |
| return status; |
| } |
| |
| void |
| nfsd4_remove_clid_dir(struct nfs4_client *clp) |
| { |
| uid_t uid; |
| gid_t gid; |
| int status; |
| |
| if (!rec_dir_init || !clp->cl_firststate) |
| return; |
| |
| clp->cl_firststate = 0; |
| nfs4_save_user(&uid, &gid); |
| status = nfsd4_unlink_clid_dir(clp->cl_recdir, HEXDIR_LEN-1); |
| nfs4_reset_user(uid, gid); |
| if (status == 0) |
| nfsd4_sync_rec_dir(); |
| if (status) |
| printk("NFSD: Failed to remove expired client state directory" |
| " %.*s\n", HEXDIR_LEN, clp->cl_recdir); |
| return; |
| } |
| |
| static int |
| purge_old(struct dentry *parent, struct dentry *child) |
| { |
| int status; |
| |
| if (nfs4_has_reclaimed_state(child->d_name.name)) |
| return 0; |
| |
| status = nfsd4_clear_clid_dir(parent, child); |
| if (status) |
| printk("failed to remove client recovery directory %s\n", |
| child->d_name.name); |
| /* Keep trying, success or failure: */ |
| return 0; |
| } |
| |
| void |
| nfsd4_recdir_purge_old(void) { |
| int status; |
| |
| if (!rec_dir_init) |
| return; |
| status = nfsd4_list_rec_dir(rec_dir.dentry, purge_old); |
| if (status == 0) |
| nfsd4_sync_rec_dir(); |
| if (status) |
| printk("nfsd4: failed to purge old clients from recovery" |
| " directory %s\n", rec_dir.dentry->d_name.name); |
| return; |
| } |
| |
| static int |
| load_recdir(struct dentry *parent, struct dentry *child) |
| { |
| if (child->d_name.len != HEXDIR_LEN - 1) { |
| printk("nfsd4: illegal name %s in recovery directory\n", |
| child->d_name.name); |
| /* Keep trying; maybe the others are OK: */ |
| return 0; |
| } |
| nfs4_client_to_reclaim(child->d_name.name); |
| return 0; |
| } |
| |
| int |
| nfsd4_recdir_load(void) { |
| int status; |
| |
| status = nfsd4_list_rec_dir(rec_dir.dentry, load_recdir); |
| if (status) |
| printk("nfsd4: failed loading clients from recovery" |
| " directory %s\n", rec_dir.dentry->d_name.name); |
| return status; |
| } |
| |
| /* |
| * Hold reference to the recovery directory. |
| */ |
| |
| void |
| nfsd4_init_recdir(char *rec_dirname) |
| { |
| uid_t uid = 0; |
| gid_t gid = 0; |
| int status; |
| |
| printk("NFSD: Using %s as the NFSv4 state recovery directory\n", |
| rec_dirname); |
| |
| BUG_ON(rec_dir_init); |
| |
| nfs4_save_user(&uid, &gid); |
| |
| status = path_lookup(rec_dirname, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, |
| &rec_dir); |
| if (status) |
| printk("NFSD: unable to find recovery directory %s\n", |
| rec_dirname); |
| |
| if (!status) |
| rec_dir_init = 1; |
| nfs4_reset_user(uid, gid); |
| } |
| |
| void |
| nfsd4_shutdown_recdir(void) |
| { |
| if (!rec_dir_init) |
| return; |
| rec_dir_init = 0; |
| path_release(&rec_dir); |
| } |