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-rw-r--r--fs/nfsd/export.c1200
1 files changed, 1200 insertions, 0 deletions
diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c
new file mode 100644
index 0000000..9a11aa3
--- /dev/null
+++ b/fs/nfsd/export.c
@@ -0,0 +1,1200 @@
+#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/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 inline 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);
+ return hash & EXPKEY_HASHMASK;
+}
+
+void expkey_put(struct cache_head *item, struct cache_detail *cd)
+{
+ if (cache_put(item, cd)) {
+ struct svc_expkey *key = container_of(item, struct svc_expkey, h);
+ if (test_bit(CACHE_VALID, &item->flags) &&
+ !test_bit(CACHE_NEGATIVE, &item->flags))
+ exp_put(key->ek_export);
+ 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_lookup(struct svc_expkey *, int);
+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;
+
+ 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 (fsidtype > 2)
+ 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);
+
+ /* now we want a pathname, or empty meaning NEGATIVE */
+ if ((len=qword_get(&mesg, buf, PAGE_SIZE)) < 0)
+ goto out;
+ dprintk("Path seems to be <%s>\n", buf);
+ err = 0;
+ if (len == 0) {
+ struct svc_expkey *ek;
+ set_bit(CACHE_NEGATIVE, &key.h.flags);
+ ek = svc_expkey_lookup(&key, 1);
+ if (ek)
+ expkey_put(&ek->h, &svc_expkey_cache);
+ } else {
+ struct nameidata nd;
+ struct svc_expkey *ek;
+ struct svc_export *exp;
+ err = path_lookup(buf, 0, &nd);
+ if (err)
+ goto out;
+
+ dprintk("Found the path %s\n", buf);
+ exp = exp_get_by_name(dom, nd.mnt, nd.dentry, NULL);
+
+ err = -ENOENT;
+ if (!exp)
+ goto out_nd;
+ key.ek_export = exp;
+ dprintk("And found export\n");
+
+ ek = svc_expkey_lookup(&key, 1);
+ if (ek)
+ expkey_put(&ek->h, &svc_expkey_cache);
+ exp_put(exp);
+ err = 0;
+ out_nd:
+ path_release(&nd);
+ }
+ cache_flush();
+ out:
+ if (dom)
+ auth_domain_put(dom);
+ if (buf)
+ 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_export->ex_mnt, ek->ek_export->ex_dentry, "\\ \t\n");
+ }
+ seq_printf(m, "\n");
+ return 0;
+}
+
+struct cache_detail svc_expkey_cache = {
+ .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,
+};
+
+static inline int svc_expkey_match (struct svc_expkey *a, struct svc_expkey *b)
+{
+ if (a->ek_fsidtype != b->ek_fsidtype ||
+ a->ek_client != b->ek_client ||
+ memcmp(a->ek_fsid, b->ek_fsid, key_len(a->ek_fsidtype)) != 0)
+ return 0;
+ return 1;
+}
+
+static inline void svc_expkey_init(struct svc_expkey *new, struct svc_expkey *item)
+{
+ cache_get(&item->ek_client->h);
+ 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 svc_expkey_update(struct svc_expkey *new, struct svc_expkey *item)
+{
+ cache_get(&item->ek_export->h);
+ new->ek_export = item->ek_export;
+}
+
+static DefineSimpleCacheLookup(svc_expkey,0) /* no inplace updates */
+
+#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 inline int svc_export_hash(struct svc_export *item)
+{
+ int rv;
+
+ rv = hash_ptr(item->ex_client, EXPORT_HASHBITS);
+ rv ^= hash_ptr(item->ex_dentry, EXPORT_HASHBITS);
+ rv ^= hash_ptr(item->ex_mnt, EXPORT_HASHBITS);
+ return rv;
+}
+
+void svc_export_put(struct cache_head *item, struct cache_detail *cd)
+{
+ if (cache_put(item, cd)) {
+ struct svc_export *exp = container_of(item, struct svc_export, h);
+ 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_lookup(struct svc_export *, int);
+
+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;
+
+ 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, 1);
+ if (expp)
+ exp_put(expp);
+ err = 0;
+ cache_flush();
+ out:
+ if (nd.dentry)
+ path_release(&nd);
+ if (dom)
+ auth_domain_put(dom);
+ if (buf)
+ 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;
+}
+struct cache_detail svc_export_cache = {
+ .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,
+};
+
+static inline int svc_export_match(struct svc_export *a, struct svc_export *b)
+{
+ return a->ex_client == b->ex_client &&
+ a->ex_dentry == b->ex_dentry &&
+ a->ex_mnt == b->ex_mnt;
+}
+static inline void svc_export_init(struct svc_export *new, struct svc_export *item)
+{
+ cache_get(&item->ex_client->h);
+ new->ex_client = item->ex_client;
+ new->ex_dentry = dget(item->ex_dentry);
+ new->ex_mnt = mntget(item->ex_mnt);
+}
+
+static inline void svc_export_update(struct svc_export *new, struct svc_export *item)
+{
+ 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 DefineSimpleCacheLookup(svc_export,1) /* allow inplace updates */
+
+
+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, 0);
+ 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_export = exp;
+ key.h.expiry_time = NEVER;
+ key.h.flags = 0;
+
+ ek = svc_expkey_lookup(&key, 1);
+ if (ek) {
+ expkey_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, 0);
+ 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;
+ expkey_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;
+ expkey_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_export &&
+ fsid_key->ek_export != exp)
+ 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, 1);
+
+ if (exp == NULL)
+ goto finish;
+
+ err = 0;
+
+ 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))
+ expkey_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;
+}
+
+/*
+ * 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;
+ 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;
+
+ rv = fh_compose(fhp, fsid_key->ek_export,
+ fsid_key->ek_export->ex_dentry, NULL);
+ expkey_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;
+ if (cache_put(&exp->h, &svc_export_cache)) BUG();
+ 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);
+ dom->h.expiry_time = get_seconds();
+ 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");
+}
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