#define MSNFS /* HACK HACK */ /* * linux/fs/nfsd/export.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/unistd.h> #include <linux/slab.h> #include <linux/sched.h> #include <linux/stat.h> #include <linux/in.h> #include <linux/seq_file.h> #include <linux/syscalls.h> #include <linux/rwsem.h> #include <linux/dcache.h> #include <linux/namei.h> #include <linux/mount.h> #include <linux/hash.h> #include <linux/module.h> #include <linux/sunrpc/svc.h> #include <linux/nfsd/nfsd.h> #include <linux/nfsd/nfsfh.h> #include <linux/nfsd/syscall.h> #include <linux/lockd/bind.h> #define NFSDDBG_FACILITY NFSDDBG_EXPORT #define NFSD_PARANOIA 1 typedef struct auth_domain svc_client; typedef struct svc_export svc_export; static void exp_do_unexport(svc_export *unexp); static int exp_verify_string(char *cp, int max); /* * 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 struct cache_head *expkey_table[EXPKEY_HASHMAX]; 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)) { dput(key->ek_dentry); mntput(key->ek_mnt); } 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 svc_expkey *new, struct svc_expkey *old); static struct svc_expkey *svc_expkey_lookup(struct svc_expkey *); static struct cache_detail svc_expkey_cache; 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; 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(&key); err = -ENOMEM; if (!ek) goto out; /* now we want a pathname, or empty meaning NEGATIVE */ err = -EINVAL; if ((len=qword_get(&mesg, buf, PAGE_SIZE)) < 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(&key, ek); if (ek) cache_put(&ek->h, &svc_expkey_cache); else err = -ENOMEM; } else { struct nameidata nd; err = path_lookup(buf, 0, &nd); if (err) goto out; dprintk("Found the path %s\n", buf); key.ek_mnt = nd.mnt; key.ek_dentry = nd.dentry; ek = svc_expkey_update(&key, ek); if (ek) cache_put(&ek->h, &svc_expkey_cache); else err = -ENOMEM; path_release(&nd); } cache_flush(); out: 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 ; 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%08x", ek->ek_client->name, ek->ek_fsidtype, ek->ek_fsid[0]); if (ek->ek_fsidtype != 1) seq_printf(m, "%08x", ek->ek_fsid[1]); if (ek->ek_fsidtype == 2) seq_printf(m, "%08x", ek->ek_fsid[2]); if (test_bit(CACHE_VALID, &h->flags) && !test_bit(CACHE_NEGATIVE, &h->flags)) { seq_printf(m, " "); seq_path(m, ek->ek_mnt, ek->ek_dentry, "\\ \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; new->ek_fsid[0] = item->ek_fsid[0]; new->ek_fsid[1] = item->ek_fsid[1]; new->ek_fsid[2] = item->ek_fsid[2]; } 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_mnt = mntget(item->ek_mnt); new->ek_dentry = dget(item->ek_dentry); } 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 = { .owner = THIS_MODULE, .hash_size = EXPKEY_HASHMAX, .hash_table = expkey_table, .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 struct svc_expkey * svc_expkey_lookup(struct svc_expkey *item) { struct cache_head *ch; 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; ch = sunrpc_cache_lookup(&svc_expkey_cache, &item->h, hash); if (ch) return container_of(ch, struct svc_expkey, h); else return NULL; } static struct svc_expkey * svc_expkey_update(struct svc_expkey *new, struct svc_expkey *old) { struct cache_head *ch; int hash = new->ek_fsidtype; char * cp = (char*)new->ek_fsid; int len = key_len(new->ek_fsidtype); hash ^= hash_mem(cp, len, EXPKEY_HASHBITS); hash ^= hash_ptr(new->ek_client, EXPKEY_HASHBITS); hash &= EXPKEY_HASHMASK; ch = sunrpc_cache_update(&svc_expkey_cache, &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) #define EXPORT_HASHMASK (EXPORT_HASHMAX -1) static struct cache_head *export_table[EXPORT_HASHMAX]; static void svc_export_put(struct kref *ref) { struct svc_export *exp = container_of(ref, struct svc_export, h.ref); dput(exp->ex_dentry); mntput(exp->ex_mnt); auth_domain_put(exp->ex_client); 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_dentry, exp->ex_mnt, *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) { /* We currently export only dirs and regular files. * This is what umountd does. */ if (!S_ISDIR(inode->i_mode) && !S_ISREG(inode->i_mode)) return -ENOTDIR; /* 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 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)) { dprintk("exp_export: export of non-dev fs without fsid"); return -EINVAL; } if (!inode->i_sb->s_export_op) { dprintk("exp_export: export of invalid fs type.\n"); return -EINVAL; } /* Ok, we can export it */; if (!inode->i_sb->s_export_op->find_exported_dentry) inode->i_sb->s_export_op->find_exported_dentry = find_exported_dentry; 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 nameidata nd; struct svc_export exp, *expp; int an_int; nd.dentry = NULL; if (mesg[mlen-1] != '\n') return -EINVAL; mesg[mlen-1] = 0; buf = kmalloc(PAGE_SIZE, GFP_KERNEL); err = -ENOMEM; if (!buf) goto out; /* client */ len = qword_get(&mesg, buf, PAGE_SIZE); err = -EINVAL; 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 out; err = path_lookup(buf, 0, &nd); if (err) goto out_no_path; exp.h.flags = 0; exp.ex_client = dom; exp.ex_mnt = nd.mnt; exp.ex_dentry = nd.dentry; /* expiry */ err = -EINVAL; exp.h.expiry_time = get_expiry(&mesg); if (exp.h.expiry_time == 0) goto out; /* flags */ err = get_int(&mesg, &an_int); if (err == -ENOENT) set_bit(CACHE_NEGATIVE, &exp.h.flags); else { if (err || an_int < 0) goto out; exp.ex_flags= an_int; /* anon uid */ err = get_int(&mesg, &an_int); if (err) goto out; exp.ex_anon_uid= an_int; /* anon gid */ err = get_int(&mesg, &an_int); if (err) goto out; exp.ex_anon_gid= an_int; /* fsid */ err = get_int(&mesg, &an_int); if (err) goto out; exp.ex_fsid = an_int; err = check_export(nd.dentry->d_inode, exp.ex_flags); if (err) goto out; } 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); out: if (nd.dentry) path_release(&nd); out_no_path: if (dom) auth_domain_put(dom); kfree(buf); return err; } static void exp_flags(struct seq_file *m, int flag, int fsid, uid_t anonu, uid_t anong); 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_mnt, exp->ex_dentry, " \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); 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_dentry == new->ex_dentry && orig->ex_mnt == new->ex_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_dentry = dget(item->ex_dentry); new->ex_mnt = mntget(item->ex_mnt); } 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); 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; } 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; } struct cache_detail svc_export_cache = { .owner = THIS_MODULE, .hash_size = EXPORT_HASHMAX, .hash_table = export_table, .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 struct svc_export * svc_export_lookup(struct svc_export *exp) { struct cache_head *ch; int hash; hash = hash_ptr(exp->ex_client, EXPORT_HASHBITS); hash ^= hash_ptr(exp->ex_dentry, EXPORT_HASHBITS); hash ^= hash_ptr(exp->ex_mnt, EXPORT_HASHBITS); ch = sunrpc_cache_lookup(&svc_export_cache, &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; hash = hash_ptr(old->ex_client, EXPORT_HASHBITS); hash ^= hash_ptr(old->ex_dentry, EXPORT_HASHBITS); hash ^= hash_ptr(old->ex_mnt, EXPORT_HASHBITS); ch = sunrpc_cache_update(&svc_export_cache, &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(svc_client *clp, int fsid_type, u32 *fsidv, struct cache_req *reqp) { struct svc_expkey key, *ek; int err; if (!clp) return NULL; key.ek_client = clp; key.ek_fsidtype = fsid_type; memcpy(key.ek_fsid, fsidv, key_len(fsid_type)); ek = svc_expkey_lookup(&key); if (ek != NULL) if ((err = cache_check(&svc_expkey_cache, &ek->h, reqp))) ek = ERR_PTR(err); return ek; } static int exp_set_key(svc_client *clp, int fsid_type, u32 *fsidv, struct svc_export *exp) { struct svc_expkey key, *ek; key.ek_client = clp; key.ek_fsidtype = fsid_type; memcpy(key.ek_fsid, fsidv, key_len(fsid_type)); key.ek_mnt = exp->ex_mnt; key.ek_dentry = exp->ex_dentry; key.h.expiry_time = NEVER; key.h.flags = 0; ek = svc_expkey_lookup(&key); if (ek) ek = svc_expkey_update(&key,ek); if (ek) { cache_put(&ek->h, &svc_expkey_cache); return 0; } return -ENOMEM; } /* * Find the client's export entry matching xdev/xino. */ static inline struct svc_expkey * exp_get_key(svc_client *clp, dev_t dev, ino_t ino) { u32 fsidv[3]; if (old_valid_dev(dev)) { mk_fsid_v0(fsidv, dev, ino); return exp_find_key(clp, 0, fsidv, NULL); } mk_fsid_v3(fsidv, dev, ino); return exp_find_key(clp, 3, fsidv, NULL); } /* * Find the client's export entry matching fsid */ static inline struct svc_expkey * exp_get_fsid_key(svc_client *clp, int fsid) { u32 fsidv[2]; mk_fsid_v1(fsidv, fsid); return exp_find_key(clp, 1, fsidv, NULL); } svc_export * exp_get_by_name(svc_client *clp, struct vfsmount *mnt, struct dentry *dentry, struct cache_req *reqp) { struct svc_export *exp, key; if (!clp) return NULL; key.ex_client = clp; key.ex_mnt = mnt; key.ex_dentry = dentry; exp = svc_export_lookup(&key); if (exp != NULL) switch (cache_check(&svc_export_cache, &exp->h, reqp)) { case 0: break; case -EAGAIN: exp = ERR_PTR(-EAGAIN); break; default: exp = NULL; } return exp; } /* * Find the export entry for a given dentry. */ struct svc_export * exp_parent(svc_client *clp, struct vfsmount *mnt, struct dentry *dentry, struct cache_req *reqp) { svc_export *exp; dget(dentry); exp = exp_get_by_name(clp, mnt, dentry, reqp); while (exp == NULL && !IS_ROOT(dentry)) { struct dentry *parent; parent = dget_parent(dentry); dput(dentry); dentry = parent; exp = exp_get_by_name(clp, mnt, dentry, reqp); } dput(dentry); return exp; } /* * Hashtable locking. Write locks are placed only by user processes * wanting to modify export information. * Write locking only done in this file. Read locking * needed externally. */ static DECLARE_RWSEM(hash_sem); void exp_readlock(void) { down_read(&hash_sem); } static inline void exp_writelock(void) { down_write(&hash_sem); } void exp_readunlock(void) { up_read(&hash_sem); } static inline void exp_writeunlock(void) { up_write(&hash_sem); } static void exp_fsid_unhash(struct svc_export *exp) { struct svc_expkey *ek; if ((exp->ex_flags & NFSEXP_FSID) == 0) return; ek = exp_get_fsid_key(exp->ex_client, exp->ex_fsid); if (ek && !IS_ERR(ek)) { ek->h.expiry_time = get_seconds()-1; cache_put(&ek->h, &svc_expkey_cache); } svc_expkey_cache.nextcheck = get_seconds(); } static int exp_fsid_hash(svc_client *clp, struct svc_export *exp) { u32 fsid[2]; if ((exp->ex_flags & NFSEXP_FSID) == 0) return 0; mk_fsid_v1(fsid, exp->ex_fsid); return exp_set_key(clp, 1, fsid, exp); } static int exp_hash(struct auth_domain *clp, struct svc_export *exp) { u32 fsid[2]; struct inode *inode = exp->ex_dentry->d_inode; dev_t dev = inode->i_sb->s_dev; if (old_valid_dev(dev)) { mk_fsid_v0(fsid, dev, inode->i_ino); return exp_set_key(clp, 0, fsid, exp); } mk_fsid_v3(fsid, dev, inode->i_ino); return exp_set_key(clp, 3, fsid, exp); } static void exp_unhash(struct svc_export *exp) { struct svc_expkey *ek; struct inode *inode = exp->ex_dentry->d_inode; ek = exp_get_key(exp->ex_client, inode->i_sb->s_dev, inode->i_ino); if (ek && !IS_ERR(ek)) { ek->h.expiry_time = get_seconds()-1; cache_put(&ek->h, &svc_expkey_cache); } svc_expkey_cache.nextcheck = get_seconds(); } /* * Export a file system. */ int exp_export(struct nfsctl_export *nxp) { svc_client *clp; struct svc_export *exp = NULL; struct svc_export new; struct svc_expkey *fsid_key = NULL; struct nameidata nd; int err; /* Consistency check */ err = -EINVAL; if (!exp_verify_string(nxp->ex_path, NFS_MAXPATHLEN) || !exp_verify_string(nxp->ex_client, NFSCLNT_IDMAX)) goto out; dprintk("exp_export called for %s:%s (%x/%ld fl %x).\n", nxp->ex_client, nxp->ex_path, (unsigned)nxp->ex_dev, (long)nxp->ex_ino, nxp->ex_flags); /* Try to lock the export table for update */ exp_writelock(); /* Look up client info */ if (!(clp = auth_domain_find(nxp->ex_client))) goto out_unlock; /* Look up the dentry */ err = path_lookup(nxp->ex_path, 0, &nd); if (err) goto out_unlock; err = -EINVAL; exp = exp_get_by_name(clp, nd.mnt, nd.dentry, NULL); /* must make sure there won't be an ex_fsid clash */ if ((nxp->ex_flags & NFSEXP_FSID) && (fsid_key = exp_get_fsid_key(clp, nxp->ex_dev)) && !IS_ERR(fsid_key) && fsid_key->ek_mnt && (fsid_key->ek_mnt != nd.mnt || fsid_key->ek_dentry != nd.dentry) ) goto finish; if (exp) { /* just a flags/id/fsid update */ exp_fsid_unhash(exp); exp->ex_flags = nxp->ex_flags; exp->ex_anon_uid = nxp->ex_anon_uid; exp->ex_anon_gid = nxp->ex_anon_gid; exp->ex_fsid = nxp->ex_dev; err = exp_fsid_hash(clp, exp); goto finish; } err = check_export(nd.dentry->d_inode, nxp->ex_flags); if (err) goto finish; err = -ENOMEM; dprintk("nfsd: creating export entry %p for client %p\n", exp, clp); new.h.expiry_time = NEVER; new.h.flags = 0; new.ex_client = clp; new.ex_mnt = nd.mnt; new.ex_dentry = nd.dentry; new.ex_flags = nxp->ex_flags; new.ex_anon_uid = nxp->ex_anon_uid; new.ex_anon_gid = nxp->ex_anon_gid; new.ex_fsid = nxp->ex_dev; exp = svc_export_lookup(&new); if (exp) exp = svc_export_update(&new, exp); if (!exp) goto finish; if (exp_hash(clp, exp) || exp_fsid_hash(clp, exp)) { /* failed to create at least one index */ exp_do_unexport(exp); cache_flush(); err = -ENOMEM; } finish: if (exp) exp_put(exp); if (fsid_key && !IS_ERR(fsid_key)) cache_put(&fsid_key->h, &svc_expkey_cache); if (clp) auth_domain_put(clp); path_release(&nd); out_unlock: exp_writeunlock(); out: return err; } /* * Unexport a file system. The export entry has already * been removed from the client's list of exported fs's. */ static void exp_do_unexport(svc_export *unexp) { unexp->h.expiry_time = get_seconds()-1; svc_export_cache.nextcheck = get_seconds(); exp_unhash(unexp); exp_fsid_unhash(unexp); } /* * unexport syscall. */ int exp_unexport(struct nfsctl_export *nxp) { struct auth_domain *dom; svc_export *exp; struct nameidata nd; int err; /* Consistency check */ if (!exp_verify_string(nxp->ex_path, NFS_MAXPATHLEN) || !exp_verify_string(nxp->ex_client, NFSCLNT_IDMAX)) return -EINVAL; exp_writelock(); err = -EINVAL; dom = auth_domain_find(nxp->ex_client); if (!dom) { dprintk("nfsd: unexport couldn't find %s\n", nxp->ex_client); goto out_unlock; } err = path_lookup(nxp->ex_path, 0, &nd); if (err) goto out_domain; err = -EINVAL; exp = exp_get_by_name(dom, nd.mnt, nd.dentry, NULL); path_release(&nd); if (!exp) goto out_domain; exp_do_unexport(exp); exp_put(exp); err = 0; out_domain: auth_domain_put(dom); cache_flush(); out_unlock: exp_writeunlock(); return err; } /* * 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(svc_client *clp, char *path, struct knfsd_fh *f, int maxsize) { struct svc_export *exp; struct nameidata nd; struct inode *inode; struct svc_fh fh; int err; err = -EPERM; /* NB: we probably ought to check that it's NUL-terminated */ if (path_lookup(path, 0, &nd)) { printk("nfsd: exp_rootfh path not found %s", path); return err; } inode = nd.dentry->d_inode; dprintk("nfsd: exp_rootfh(%s [%p] %s:%s/%ld)\n", path, nd.dentry, clp->name, inode->i_sb->s_id, inode->i_ino); exp = exp_parent(clp, nd.mnt, nd.dentry, NULL); if (!exp) { dprintk("nfsd: exp_rootfh export not found.\n"); goto out; } /* * fh must be initialized before calling fh_compose */ fh_init(&fh, maxsize); if (fh_compose(&fh, exp, nd.dentry, NULL)) err = -EINVAL; else err = 0; memcpy(f, &fh.fh_handle, sizeof(struct knfsd_fh)); fh_put(&fh); exp_put(exp); out: path_release(&nd); return err; } struct svc_export * exp_find(struct auth_domain *clp, int fsid_type, u32 *fsidv, struct cache_req *reqp) { struct svc_export *exp; struct svc_expkey *ek = exp_find_key(clp, fsid_type, fsidv, reqp); if (!ek || IS_ERR(ek)) return ERR_PTR(PTR_ERR(ek)); exp = exp_get_by_name(clp, ek->ek_mnt, ek->ek_dentry, reqp); cache_put(&ek->h, &svc_expkey_cache); if (!exp || IS_ERR(exp)) return ERR_PTR(PTR_ERR(exp)); return exp; } /* * 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 */ int exp_pseudoroot(struct auth_domain *clp, struct svc_fh *fhp, struct cache_req *creq) { struct svc_expkey *fsid_key; struct svc_export *exp; int rv; u32 fsidv[2]; mk_fsid_v1(fsidv, 0); fsid_key = exp_find_key(clp, 1, fsidv, creq); if (IS_ERR(fsid_key) && PTR_ERR(fsid_key) == -EAGAIN) return nfserr_dropit; if (!fsid_key || IS_ERR(fsid_key)) return nfserr_perm; exp = exp_get_by_name(clp, fsid_key->ek_mnt, fsid_key->ek_dentry, creq); if (exp == NULL) rv = nfserr_perm; else if (IS_ERR(exp)) rv = nfserrno(PTR_ERR(exp)); else { rv = fh_compose(fhp, exp, fsid_key->ek_dentry, NULL); exp_put(exp); } cache_put(&fsid_key->h, &svc_expkey_cache); return rv; } /* Iterator */ static void *e_start(struct seq_file *m, loff_t *pos) { loff_t n = *pos; unsigned hash, export; struct cache_head *ch; exp_readlock(); read_lock(&svc_export_cache.hash_lock); if (!n--) return (void *)1; 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); if (p == (void *)1) 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) { read_unlock(&svc_export_cache.hash_lock); exp_readunlock(); } 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", ""}}, #ifdef MSNFS { NFSEXP_MSNFS, {"msnfs", ""}}, #endif { 0, {"", ""}} }; static void exp_flags(struct seq_file *m, int flag, int fsid, uid_t anonu, uid_t anong) { int first = 0; struct flags *flg; for (flg = expflags; flg->flag; flg++) { int state = (flg->flag & flag)?0:1; if (*flg->name[state]) seq_printf(m, "%s%s", first++?",":"", flg->name[state]); } if (flag & NFSEXP_FSID) seq_printf(m, "%sfsid=%d", first++?",":"", fsid); if (anonu != (uid_t)-2 && anonu != (0x10000-2)) seq_printf(m, "%sanonuid=%d", first++?",":"", anonu); if (anong != (gid_t)-2 && anong != (0x10000-2)) seq_printf(m, "%sanongid=%d", first++?",":"", anong); } 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); svc_client *clp; if (p == (void *)1) { seq_puts(m, "# Version 1.1\n"); seq_puts(m, "# Path Client(Flags) # IPs\n"); return 0; } clp = exp->ex_client; cache_get(&exp->h); if (cache_check(&svc_export_cache, &exp->h, NULL)) return 0; cache_put(&exp->h, &svc_export_cache); return svc_export_show(m, &svc_export_cache, cp); } struct seq_operations nfs_exports_op = { .start = e_start, .next = e_next, .stop = e_stop, .show = e_show, }; /* * Add or modify a client. * Change requests may involve the list of host addresses. The list of * exports and possibly existing uid maps are left untouched. */ int exp_addclient(struct nfsctl_client *ncp) { struct auth_domain *dom; int i, err; /* First, consistency check. */ err = -EINVAL; if (! exp_verify_string(ncp->cl_ident, NFSCLNT_IDMAX)) goto out; if (ncp->cl_naddr > NFSCLNT_ADDRMAX) goto out; /* Lock the hashtable */ exp_writelock(); dom = unix_domain_find(ncp->cl_ident); err = -ENOMEM; if (!dom) goto out_unlock; /* Insert client into hashtable. */ for (i = 0; i < ncp->cl_naddr; i++) auth_unix_add_addr(ncp->cl_addrlist[i], dom); auth_unix_forget_old(dom); auth_domain_put(dom); err = 0; out_unlock: exp_writeunlock(); out: return err; } /* * Delete a client given an identifier. */ int exp_delclient(struct nfsctl_client *ncp) { int err; struct auth_domain *dom; err = -EINVAL; if (!exp_verify_string(ncp->cl_ident, NFSCLNT_IDMAX)) goto out; /* Lock the hashtable */ exp_writelock(); dom = auth_domain_find(ncp->cl_ident); /* just make sure that no addresses work * and that it will expire soon */ if (dom) { err = auth_unix_forget_old(dom); auth_domain_put(dom); } exp_writeunlock(); out: return err; } /* * Verify that string is non-empty and does not exceed max length. */ static int exp_verify_string(char *cp, int max) { int i; for (i = 0; i < max; i++) if (!cp[i]) return i; cp[i] = 0; printk(KERN_NOTICE "nfsd: couldn't validate string %s\n", cp); return 0; } /* * Initialize the exports module. */ void nfsd_export_init(void) { dprintk("nfsd: initializing export module.\n"); cache_register(&svc_export_cache); cache_register(&svc_expkey_cache); } /* * Flush exports table - called when last nfsd thread is killed */ void nfsd_export_flush(void) { exp_writelock(); cache_purge(&svc_expkey_cache); cache_purge(&svc_export_cache); exp_writeunlock(); } /* * Shutdown the exports module. */ void nfsd_export_shutdown(void) { dprintk("nfsd: shutting down export module.\n"); exp_writelock(); if (cache_unregister(&svc_expkey_cache)) printk(KERN_ERR "nfsd: failed to unregister expkey cache\n"); if (cache_unregister(&svc_export_cache)) printk(KERN_ERR "nfsd: failed to unregister export cache\n"); svcauth_unix_purge(); exp_writeunlock(); dprintk("nfsd: export shutdown complete.\n"); }