1/*
   2 * NFS exporting and validation.
   3 *
   4 * We maintain a list of clients, each of which has a list of
   5 * exports. To export an fs to a given client, you first have
   6 * to create the client entry with NFSCTL_ADDCLIENT, which
   7 * creates a client control block and adds it to the hash
   8 * table. Then, you call NFSCTL_EXPORT for each fs.
   9 *
  10 *
  11 * Copyright (C) 1995, 1996 Olaf Kirch, <okir@monad.swb.de>
  12 */
  13
  14#include <linux/slab.h>
  15#include <linux/namei.h>
  16#include <linux/module.h>
  17#include <linux/exportfs.h>
  18#include <linux/sunrpc/svc_xprt.h>
  19
  20#include "nfsd.h"
  21#include "nfsfh.h"
  22#include "netns.h"
  23#include "pnfs.h"
  24
  25#define NFSDDBG_FACILITY	NFSDDBG_EXPORT
  26
  27/*
  28 * We have two caches.
  29 * One maps client+vfsmnt+dentry to export options - the export map
  30 * The other maps client+filehandle-fragment to export options. - the expkey map
  31 *
  32 * The export options are actually stored in the first map, and the
  33 * second map contains a reference to the entry in the first map.
  34 */
  35
  36#define	EXPKEY_HASHBITS		8
  37#define	EXPKEY_HASHMAX		(1 << EXPKEY_HASHBITS)
  38#define	EXPKEY_HASHMASK		(EXPKEY_HASHMAX -1)
  39
  40static void expkey_put(struct kref *ref)
  41{
  42	struct svc_expkey *key = container_of(ref, struct svc_expkey, h.ref);
  43
  44	if (test_bit(CACHE_VALID, &key->h.flags) &&
  45	    !test_bit(CACHE_NEGATIVE, &key->h.flags))
  46		path_put(&key->ek_path);
  47	auth_domain_put(key->ek_client);
  48	kfree(key);
  49}
  50
  51static void expkey_request(struct cache_detail *cd,
  52			   struct cache_head *h,
  53			   char **bpp, int *blen)
  54{
  55	/* client fsidtype \xfsid */
  56	struct svc_expkey *ek = container_of(h, struct svc_expkey, h);
  57	char type[5];
  58
  59	qword_add(bpp, blen, ek->ek_client->name);
  60	snprintf(type, 5, "%d", ek->ek_fsidtype);
  61	qword_add(bpp, blen, type);
  62	qword_addhex(bpp, blen, (char*)ek->ek_fsid, key_len(ek->ek_fsidtype));
  63	(*bpp)[-1] = '\n';
  64}
  65
  66static struct svc_expkey *svc_expkey_update(struct cache_detail *cd, struct svc_expkey *new,
  67					    struct svc_expkey *old);
  68static struct svc_expkey *svc_expkey_lookup(struct cache_detail *cd, struct svc_expkey *);
  69
  70static int expkey_parse(struct cache_detail *cd, char *mesg, int mlen)
  71{
  72	/* client fsidtype fsid expiry [path] */
  73	char *buf;
  74	int len;
  75	struct auth_domain *dom = NULL;
  76	int err;
  77	int fsidtype;
  78	char *ep;
  79	struct svc_expkey key;
  80	struct svc_expkey *ek = NULL;
  81
  82	if (mesg[mlen - 1] != '\n')
  83		return -EINVAL;
  84	mesg[mlen-1] = 0;
  85
  86	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
  87	err = -ENOMEM;
  88	if (!buf)
  89		goto out;
  90
  91	err = -EINVAL;
  92	if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
  93		goto out;
  94
  95	err = -ENOENT;
  96	dom = auth_domain_find(buf);
  97	if (!dom)
  98		goto out;
  99	dprintk("found domain %s\n", buf);
 100
 101	err = -EINVAL;
 102	if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
 103		goto out;
 104	fsidtype = simple_strtoul(buf, &ep, 10);
 105	if (*ep)
 106		goto out;
 107	dprintk("found fsidtype %d\n", fsidtype);
 108	if (key_len(fsidtype)==0) /* invalid type */
 109		goto out;
 110	if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
 111		goto out;
 112	dprintk("found fsid length %d\n", len);
 113	if (len != key_len(fsidtype))
 114		goto out;
 115
 116	/* OK, we seem to have a valid key */
 117	key.h.flags = 0;
 118	key.h.expiry_time = get_expiry(&mesg);
 119	if (key.h.expiry_time == 0)
 120		goto out;
 121
 122	key.ek_client = dom;	
 123	key.ek_fsidtype = fsidtype;
 124	memcpy(key.ek_fsid, buf, len);
 125
 126	ek = svc_expkey_lookup(cd, &key);
 127	err = -ENOMEM;
 128	if (!ek)
 129		goto out;
 130
 131	/* now we want a pathname, or empty meaning NEGATIVE  */
 132	err = -EINVAL;
 133	len = qword_get(&mesg, buf, PAGE_SIZE);
 134	if (len < 0)
 135		goto out;
 136	dprintk("Path seems to be <%s>\n", buf);
 137	err = 0;
 138	if (len == 0) {
 139		set_bit(CACHE_NEGATIVE, &key.h.flags);
 140		ek = svc_expkey_update(cd, &key, ek);
 141		if (!ek)
 142			err = -ENOMEM;
 143	} else {
 144		err = kern_path(buf, 0, &key.ek_path);
 145		if (err)
 146			goto out;
 147
 148		dprintk("Found the path %s\n", buf);
 149
 150		ek = svc_expkey_update(cd, &key, ek);
 151		if (!ek)
 152			err = -ENOMEM;
 153		path_put(&key.ek_path);
 154	}
 155	cache_flush();
 156 out:
 157	if (ek)
 158		cache_put(&ek->h, cd);
 159	if (dom)
 160		auth_domain_put(dom);
 161	kfree(buf);
 162	return err;
 163}
 164
 165static int expkey_show(struct seq_file *m,
 166		       struct cache_detail *cd,
 167		       struct cache_head *h)
 168{
 169	struct svc_expkey *ek ;
 170	int i;
 171
 172	if (h ==NULL) {
 173		seq_puts(m, "#domain fsidtype fsid [path]\n");
 174		return 0;
 175	}
 176	ek = container_of(h, struct svc_expkey, h);
 177	seq_printf(m, "%s %d 0x", ek->ek_client->name,
 178		   ek->ek_fsidtype);
 179	for (i=0; i < key_len(ek->ek_fsidtype)/4; i++)
 180		seq_printf(m, "%08x", ek->ek_fsid[i]);
 181	if (test_bit(CACHE_VALID, &h->flags) && 
 182	    !test_bit(CACHE_NEGATIVE, &h->flags)) {
 183		seq_printf(m, " ");
 184		seq_path(m, &ek->ek_path, "\\ \t\n");
 185	}
 186	seq_printf(m, "\n");
 187	return 0;
 188}
 189
 190static inline int expkey_match (struct cache_head *a, struct cache_head *b)
 191{
 192	struct svc_expkey *orig = container_of(a, struct svc_expkey, h);
 193	struct svc_expkey *new = container_of(b, struct svc_expkey, h);
 194
 195	if (orig->ek_fsidtype != new->ek_fsidtype ||
 196	    orig->ek_client != new->ek_client ||
 197	    memcmp(orig->ek_fsid, new->ek_fsid, key_len(orig->ek_fsidtype)) != 0)
 198		return 0;
 199	return 1;
 200}
 201
 202static inline void expkey_init(struct cache_head *cnew,
 203				   struct cache_head *citem)
 204{
 205	struct svc_expkey *new = container_of(cnew, struct svc_expkey, h);
 206	struct svc_expkey *item = container_of(citem, struct svc_expkey, h);
 207
 208	kref_get(&item->ek_client->ref);
 209	new->ek_client = item->ek_client;
 210	new->ek_fsidtype = item->ek_fsidtype;
 211
 212	memcpy(new->ek_fsid, item->ek_fsid, sizeof(new->ek_fsid));
 213}
 214
 215static inline void expkey_update(struct cache_head *cnew,
 216				   struct cache_head *citem)
 217{
 218	struct svc_expkey *new = container_of(cnew, struct svc_expkey, h);
 219	struct svc_expkey *item = container_of(citem, struct svc_expkey, h);
 220
 221	new->ek_path = item->ek_path;
 222	path_get(&item->ek_path);
 223}
 224
 225static struct cache_head *expkey_alloc(void)
 226{
 227	struct svc_expkey *i = kmalloc(sizeof(*i), GFP_KERNEL);
 228	if (i)
 229		return &i->h;
 230	else
 231		return NULL;
 232}
 233
 234static struct cache_detail svc_expkey_cache_template = {
 235	.owner		= THIS_MODULE,
 236	.hash_size	= EXPKEY_HASHMAX,
 237	.name		= "nfsd.fh",
 238	.cache_put	= expkey_put,
 239	.cache_request	= expkey_request,
 240	.cache_parse	= expkey_parse,
 241	.cache_show	= expkey_show,
 242	.match		= expkey_match,
 243	.init		= expkey_init,
 244	.update       	= expkey_update,
 245	.alloc		= expkey_alloc,
 246};
 247
 248static int
 249svc_expkey_hash(struct svc_expkey *item)
 250{
 251	int hash = item->ek_fsidtype;
 252	char * cp = (char*)item->ek_fsid;
 253	int len = key_len(item->ek_fsidtype);
 254
 255	hash ^= hash_mem(cp, len, EXPKEY_HASHBITS);
 256	hash ^= hash_ptr(item->ek_client, EXPKEY_HASHBITS);
 257	hash &= EXPKEY_HASHMASK;
 258	return hash;
 259}
 260
 261static struct svc_expkey *
 262svc_expkey_lookup(struct cache_detail *cd, struct svc_expkey *item)
 263{
 264	struct cache_head *ch;
 265	int hash = svc_expkey_hash(item);
 266
 267	ch = sunrpc_cache_lookup(cd, &item->h, hash);
 268	if (ch)
 269		return container_of(ch, struct svc_expkey, h);
 270	else
 271		return NULL;
 272}
 273
 274static struct svc_expkey *
 275svc_expkey_update(struct cache_detail *cd, struct svc_expkey *new,
 276		  struct svc_expkey *old)
 277{
 278	struct cache_head *ch;
 279	int hash = svc_expkey_hash(new);
 280
 281	ch = sunrpc_cache_update(cd, &new->h, &old->h, hash);
 282	if (ch)
 283		return container_of(ch, struct svc_expkey, h);
 284	else
 285		return NULL;
 286}
 287
 288
 289#define	EXPORT_HASHBITS		8
 290#define	EXPORT_HASHMAX		(1<< EXPORT_HASHBITS)
 291
 292static void nfsd4_fslocs_free(struct nfsd4_fs_locations *fsloc)
 293{
 294	struct nfsd4_fs_location *locations = fsloc->locations;
 295	int i;
 296
 297	if (!locations)
 298		return;
 299
 300	for (i = 0; i < fsloc->locations_count; i++) {
 301		kfree(locations[i].path);
 302		kfree(locations[i].hosts);
 303	}
 304
 305	kfree(locations);
 306	fsloc->locations = NULL;
 307}
 308
 309static void svc_export_put(struct kref *ref)
 310{
 311	struct svc_export *exp = container_of(ref, struct svc_export, h.ref);
 312	path_put(&exp->ex_path);
 313	auth_domain_put(exp->ex_client);
 314	nfsd4_fslocs_free(&exp->ex_fslocs);
 315	kfree(exp->ex_uuid);
 316	kfree(exp);
 317}
 318
 319static void svc_export_request(struct cache_detail *cd,
 320			       struct cache_head *h,
 321			       char **bpp, int *blen)
 322{
 323	/*  client path */
 324	struct svc_export *exp = container_of(h, struct svc_export, h);
 325	char *pth;
 326
 327	qword_add(bpp, blen, exp->ex_client->name);
 328	pth = d_path(&exp->ex_path, *bpp, *blen);
 329	if (IS_ERR(pth)) {
 330		/* is this correct? */
 331		(*bpp)[0] = '\n';
 332		return;
 333	}
 334	qword_add(bpp, blen, pth);
 335	(*bpp)[-1] = '\n';
 336}
 337
 338static struct svc_export *svc_export_update(struct svc_export *new,
 339					    struct svc_export *old);
 340static struct svc_export *svc_export_lookup(struct svc_export *);
 341
 342static int check_export(struct inode *inode, int *flags, unsigned char *uuid)
 343{
 344
 345	/*
 346	 * We currently export only dirs, regular files, and (for v4
 347	 * pseudoroot) symlinks.
 348	 */
 349	if (!S_ISDIR(inode->i_mode) &&
 350	    !S_ISLNK(inode->i_mode) &&
 351	    !S_ISREG(inode->i_mode))
 352		return -ENOTDIR;
 353
 354	/*
 355	 * Mountd should never pass down a writeable V4ROOT export, but,
 356	 * just to make sure:
 357	 */
 358	if (*flags & NFSEXP_V4ROOT)
 359		*flags |= NFSEXP_READONLY;
 360
 361	/* There are two requirements on a filesystem to be exportable.
 362	 * 1:  We must be able to identify the filesystem from a number.
 363	 *       either a device number (so FS_REQUIRES_DEV needed)
 364	 *       or an FSID number (so NFSEXP_FSID or ->uuid is needed).
 365	 * 2:  We must be able to find an inode from a filehandle.
 366	 *       This means that s_export_op must be set.
 367	 */
 368	if (!(inode->i_sb->s_type->fs_flags & FS_REQUIRES_DEV) &&
 369	    !(*flags & NFSEXP_FSID) &&
 370	    uuid == NULL) {
 371		dprintk("exp_export: export of non-dev fs without fsid\n");
 372		return -EINVAL;
 373	}
 374
 375	if (!inode->i_sb->s_export_op ||
 376	    !inode->i_sb->s_export_op->fh_to_dentry) {
 377		dprintk("exp_export: export of invalid fs type.\n");
 378		return -EINVAL;
 379	}
 380
 381	return 0;
 382
 383}
 384
 385#ifdef CONFIG_NFSD_V4
 386
 387static int
 388fsloc_parse(char **mesg, char *buf, struct nfsd4_fs_locations *fsloc)
 389{
 390	int len;
 391	int migrated, i, err;
 392
 393	/* more than one fsloc */
 394	if (fsloc->locations)
 395		return -EINVAL;
 396
 397	/* listsize */
 398	err = get_uint(mesg, &fsloc->locations_count);
 399	if (err)
 400		return err;
 401	if (fsloc->locations_count > MAX_FS_LOCATIONS)
 402		return -EINVAL;
 403	if (fsloc->locations_count == 0)
 404		return 0;
 405
 406	fsloc->locations = kzalloc(fsloc->locations_count
 407			* sizeof(struct nfsd4_fs_location), GFP_KERNEL);
 408	if (!fsloc->locations)
 409		return -ENOMEM;
 410	for (i=0; i < fsloc->locations_count; i++) {
 411		/* colon separated host list */
 412		err = -EINVAL;
 413		len = qword_get(mesg, buf, PAGE_SIZE);
 414		if (len <= 0)
 415			goto out_free_all;
 416		err = -ENOMEM;
 417		fsloc->locations[i].hosts = kstrdup(buf, GFP_KERNEL);
 418		if (!fsloc->locations[i].hosts)
 419			goto out_free_all;
 420		err = -EINVAL;
 421		/* slash separated path component list */
 422		len = qword_get(mesg, buf, PAGE_SIZE);
 423		if (len <= 0)
 424			goto out_free_all;
 425		err = -ENOMEM;
 426		fsloc->locations[i].path = kstrdup(buf, GFP_KERNEL);
 427		if (!fsloc->locations[i].path)
 428			goto out_free_all;
 429	}
 430	/* migrated */
 431	err = get_int(mesg, &migrated);
 432	if (err)
 433		goto out_free_all;
 434	err = -EINVAL;
 435	if (migrated < 0 || migrated > 1)
 436		goto out_free_all;
 437	fsloc->migrated = migrated;
 438	return 0;
 439out_free_all:
 440	nfsd4_fslocs_free(fsloc);
 441	return err;
 442}
 443
 444static int secinfo_parse(char **mesg, char *buf, struct svc_export *exp)
 445{
 446	struct exp_flavor_info *f;
 447	u32 listsize;
 448	int err;
 449
 450	/* more than one secinfo */
 451	if (exp->ex_nflavors)
 452		return -EINVAL;
 453
 454	err = get_uint(mesg, &listsize);
 455	if (err)
 456		return err;
 457	if (listsize > MAX_SECINFO_LIST)
 458		return -EINVAL;
 459
 460	for (f = exp->ex_flavors; f < exp->ex_flavors + listsize; f++) {
 461		err = get_uint(mesg, &f->pseudoflavor);
 462		if (err)
 463			return err;
 464		/*
 465		 * XXX: It would be nice to also check whether this
 466		 * pseudoflavor is supported, so we can discover the
 467		 * problem at export time instead of when a client fails
 468		 * to authenticate.
 469		 */
 470		err = get_uint(mesg, &f->flags);
 471		if (err)
 472			return err;
 473		/* Only some flags are allowed to differ between flavors: */
 474		if (~NFSEXP_SECINFO_FLAGS & (f->flags ^ exp->ex_flags))
 475			return -EINVAL;
 476	}
 477	exp->ex_nflavors = listsize;
 478	return 0;
 479}
 480
 481#else /* CONFIG_NFSD_V4 */
 482static inline int
 483fsloc_parse(char **mesg, char *buf, struct nfsd4_fs_locations *fsloc){return 0;}
 484static inline int
 485secinfo_parse(char **mesg, char *buf, struct svc_export *exp) { return 0; }
 486#endif
 487
 488static inline int
 489uuid_parse(char **mesg, char *buf, unsigned char **puuid)
 490{
 491	int len;
 492
 493	/* more than one uuid */
 494	if (*puuid)
 495		return -EINVAL;
 496
 497	/* expect a 16 byte uuid encoded as \xXXXX... */
 498	len = qword_get(mesg, buf, PAGE_SIZE);
 499	if (len != EX_UUID_LEN)
 500		return -EINVAL;
 501
 502	*puuid = kmemdup(buf, EX_UUID_LEN, GFP_KERNEL);
 503	if (*puuid == NULL)
 504		return -ENOMEM;
 505
 506	return 0;
 507}
 508
 509static int svc_export_parse(struct cache_detail *cd, char *mesg, int mlen)
 510{
 511	/* client path expiry [flags anonuid anongid fsid] */
 512	char *buf;
 513	int len;
 514	int err;
 515	struct auth_domain *dom = NULL;
 516	struct svc_export exp = {}, *expp;
 517	int an_int;
 518
 519	if (mesg[mlen-1] != '\n')
 520		return -EINVAL;
 521	mesg[mlen-1] = 0;
 522
 523	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
 524	if (!buf)
 525		return -ENOMEM;
 526
 527	/* client */
 528	err = -EINVAL;
 529	len = qword_get(&mesg, buf, PAGE_SIZE);
 530	if (len <= 0)
 531		goto out;
 532
 533	err = -ENOENT;
 534	dom = auth_domain_find(buf);
 535	if (!dom)
 536		goto out;
 537
 538	/* path */
 539	err = -EINVAL;
 540	if ((len = qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
 541		goto out1;
 542
 543	err = kern_path(buf, 0, &exp.ex_path);
 544	if (err)
 545		goto out1;
 546
 547	exp.ex_client = dom;
 548	exp.cd = cd;
 549	exp.ex_devid_map = NULL;
 550
 551	/* expiry */
 552	err = -EINVAL;
 553	exp.h.expiry_time = get_expiry(&mesg);
 554	if (exp.h.expiry_time == 0)
 555		goto out3;
 556
 557	/* flags */
 558	err = get_int(&mesg, &an_int);
 559	if (err == -ENOENT) {
 560		err = 0;
 561		set_bit(CACHE_NEGATIVE, &exp.h.flags);
 562	} else {
 563		if (err || an_int < 0)
 564			goto out3;
 565		exp.ex_flags= an_int;
 566	
 567		/* anon uid */
 568		err = get_int(&mesg, &an_int);
 569		if (err)
 570			goto out3;
 571		exp.ex_anon_uid= make_kuid(&init_user_ns, an_int);
 572
 573		/* anon gid */
 574		err = get_int(&mesg, &an_int);
 575		if (err)
 576			goto out3;
 577		exp.ex_anon_gid= make_kgid(&init_user_ns, an_int);
 578
 579		/* fsid */
 580		err = get_int(&mesg, &an_int);
 581		if (err)
 582			goto out3;
 583		exp.ex_fsid = an_int;
 584
 585		while ((len = qword_get(&mesg, buf, PAGE_SIZE)) > 0) {
 586			if (strcmp(buf, "fsloc") == 0)
 587				err = fsloc_parse(&mesg, buf, &exp.ex_fslocs);
 588			else if (strcmp(buf, "uuid") == 0)
 589				err = uuid_parse(&mesg, buf, &exp.ex_uuid);
 590			else if (strcmp(buf, "secinfo") == 0)
 591				err = secinfo_parse(&mesg, buf, &exp);
 592			else
 593				/* quietly ignore unknown words and anything
 594				 * following. Newer user-space can try to set
 595				 * new values, then see what the result was.
 596				 */
 597				break;
 598			if (err)
 599				goto out4;
 600		}
 601
 602		err = check_export(d_inode(exp.ex_path.dentry), &exp.ex_flags,
 603				   exp.ex_uuid);
 604		if (err)
 605			goto out4;
 606		/*
 607		 * No point caching this if it would immediately expire.
 608		 * Also, this protects exportfs's dummy export from the
 609		 * anon_uid/anon_gid checks:
 610		 */
 611		if (exp.h.expiry_time < seconds_since_boot())
 612			goto out4;
 613		/*
 614		 * For some reason exportfs has been passing down an
 615		 * invalid (-1) uid & gid on the "dummy" export which it
 616		 * uses to test export support.  To make sure exportfs
 617		 * sees errors from check_export we therefore need to
 618		 * delay these checks till after check_export:
 619		 */
 620		err = -EINVAL;
 621		if (!uid_valid(exp.ex_anon_uid))
 622			goto out4;
 623		if (!gid_valid(exp.ex_anon_gid))
 624			goto out4;
 625		err = 0;
 626
 627		nfsd4_setup_layout_type(&exp);
 628	}
 629
 630	expp = svc_export_lookup(&exp);
 631	if (expp)
 632		expp = svc_export_update(&exp, expp);
 633	else
 634		err = -ENOMEM;
 635	cache_flush();
 636	if (expp == NULL)
 637		err = -ENOMEM;
 638	else
 639		exp_put(expp);
 640out4:
 641	nfsd4_fslocs_free(&exp.ex_fslocs);
 642	kfree(exp.ex_uuid);
 643out3:
 644	path_put(&exp.ex_path);
 645out1:
 646	auth_domain_put(dom);
 647out:
 648	kfree(buf);
 649	return err;
 650}
 651
 652static void exp_flags(struct seq_file *m, int flag, int fsid,
 653		kuid_t anonu, kgid_t anong, struct nfsd4_fs_locations *fslocs);
 654static void show_secinfo(struct seq_file *m, struct svc_export *exp);
 655
 656static int svc_export_show(struct seq_file *m,
 657			   struct cache_detail *cd,
 658			   struct cache_head *h)
 659{
 660	struct svc_export *exp ;
 661
 662	if (h ==NULL) {
 663		seq_puts(m, "#path domain(flags)\n");
 664		return 0;
 665	}
 666	exp = container_of(h, struct svc_export, h);
 667	seq_path(m, &exp->ex_path, " \t\n\\");
 668	seq_putc(m, '\t');
 669	seq_escape(m, exp->ex_client->name, " \t\n\\");
 670	seq_putc(m, '(');
 671	if (test_bit(CACHE_VALID, &h->flags) && 
 672	    !test_bit(CACHE_NEGATIVE, &h->flags)) {
 673		exp_flags(m, exp->ex_flags, exp->ex_fsid,
 674			  exp->ex_anon_uid, exp->ex_anon_gid, &exp->ex_fslocs);
 675		if (exp->ex_uuid) {
 676			int i;
 677			seq_puts(m, ",uuid=");
 678			for (i = 0; i < EX_UUID_LEN; i++) {
 679				if ((i&3) == 0 && i)
 680					seq_putc(m, ':');
 681				seq_printf(m, "%02x", exp->ex_uuid[i]);
 682			}
 683		}
 684		show_secinfo(m, exp);
 685	}
 686	seq_puts(m, ")\n");
 687	return 0;
 688}
 689static int svc_export_match(struct cache_head *a, struct cache_head *b)
 690{
 691	struct svc_export *orig = container_of(a, struct svc_export, h);
 692	struct svc_export *new = container_of(b, struct svc_export, h);
 693	return orig->ex_client == new->ex_client &&
 694		path_equal(&orig->ex_path, &new->ex_path);
 695}
 696
 697static void svc_export_init(struct cache_head *cnew, struct cache_head *citem)
 698{
 699	struct svc_export *new = container_of(cnew, struct svc_export, h);
 700	struct svc_export *item = container_of(citem, struct svc_export, h);
 701
 702	kref_get(&item->ex_client->ref);
 703	new->ex_client = item->ex_client;
 704	new->ex_path = item->ex_path;
 705	path_get(&item->ex_path);
 706	new->ex_fslocs.locations = NULL;
 707	new->ex_fslocs.locations_count = 0;
 708	new->ex_fslocs.migrated = 0;
 709	new->ex_layout_type = 0;
 710	new->ex_uuid = NULL;
 711	new->cd = item->cd;
 712}
 713
 714static void export_update(struct cache_head *cnew, struct cache_head *citem)
 715{
 716	struct svc_export *new = container_of(cnew, struct svc_export, h);
 717	struct svc_export *item = container_of(citem, struct svc_export, h);
 718	int i;
 719
 720	new->ex_flags = item->ex_flags;
 721	new->ex_anon_uid = item->ex_anon_uid;
 722	new->ex_anon_gid = item->ex_anon_gid;
 723	new->ex_fsid = item->ex_fsid;
 724	new->ex_devid_map = item->ex_devid_map;
 725	item->ex_devid_map = NULL;
 726	new->ex_uuid = item->ex_uuid;
 727	item->ex_uuid = NULL;
 728	new->ex_fslocs.locations = item->ex_fslocs.locations;
 729	item->ex_fslocs.locations = NULL;
 730	new->ex_fslocs.locations_count = item->ex_fslocs.locations_count;
 731	item->ex_fslocs.locations_count = 0;
 732	new->ex_fslocs.migrated = item->ex_fslocs.migrated;
 733	item->ex_fslocs.migrated = 0;
 734	new->ex_layout_type = item->ex_layout_type;
 735	new->ex_nflavors = item->ex_nflavors;
 736	for (i = 0; i < MAX_SECINFO_LIST; i++) {
 737		new->ex_flavors[i] = item->ex_flavors[i];
 738	}
 739}
 740
 741static struct cache_head *svc_export_alloc(void)
 742{
 743	struct svc_export *i = kmalloc(sizeof(*i), GFP_KERNEL);
 744	if (i)
 745		return &i->h;
 746	else
 747		return NULL;
 748}
 749
 750static struct cache_detail svc_export_cache_template = {
 751	.owner		= THIS_MODULE,
 752	.hash_size	= EXPORT_HASHMAX,
 753	.name		= "nfsd.export",
 754	.cache_put	= svc_export_put,
 755	.cache_request	= svc_export_request,
 756	.cache_parse	= svc_export_parse,
 757	.cache_show	= svc_export_show,
 758	.match		= svc_export_match,
 759	.init		= svc_export_init,
 760	.update		= export_update,
 761	.alloc		= svc_export_alloc,
 762};
 763
 764static int
 765svc_export_hash(struct svc_export *exp)
 766{
 767	int hash;
 768
 769	hash = hash_ptr(exp->ex_client, EXPORT_HASHBITS);
 770	hash ^= hash_ptr(exp->ex_path.dentry, EXPORT_HASHBITS);
 771	hash ^= hash_ptr(exp->ex_path.mnt, EXPORT_HASHBITS);
 772	return hash;
 773}
 774
 775static struct svc_export *
 776svc_export_lookup(struct svc_export *exp)
 777{
 778	struct cache_head *ch;
 779	int hash = svc_export_hash(exp);
 780
 781	ch = sunrpc_cache_lookup(exp->cd, &exp->h, hash);
 782	if (ch)
 783		return container_of(ch, struct svc_export, h);
 784	else
 785		return NULL;
 786}
 787
 788static struct svc_export *
 789svc_export_update(struct svc_export *new, struct svc_export *old)
 790{
 791	struct cache_head *ch;
 792	int hash = svc_export_hash(old);
 793
 794	ch = sunrpc_cache_update(old->cd, &new->h, &old->h, hash);
 795	if (ch)
 796		return container_of(ch, struct svc_export, h);
 797	else
 798		return NULL;
 799}
 800
 801
 802static struct svc_expkey *
 803exp_find_key(struct cache_detail *cd, struct auth_domain *clp, int fsid_type,
 804	     u32 *fsidv, struct cache_req *reqp)
 805{
 806	struct svc_expkey key, *ek;
 807	int err;
 808	
 809	if (!clp)
 810		return ERR_PTR(-ENOENT);
 811
 812	key.ek_client = clp;
 813	key.ek_fsidtype = fsid_type;
 814	memcpy(key.ek_fsid, fsidv, key_len(fsid_type));
 815
 816	ek = svc_expkey_lookup(cd, &key);
 817	if (ek == NULL)
 818		return ERR_PTR(-ENOMEM);
 819	err = cache_check(cd, &ek->h, reqp);
 820	if (err)
 821		return ERR_PTR(err);
 822	return ek;
 823}
 824
 825static struct svc_export *
 826exp_get_by_name(struct cache_detail *cd, struct auth_domain *clp,
 827		const struct path *path, struct cache_req *reqp)
 828{
 829	struct svc_export *exp, key;
 830	int err;
 831
 832	if (!clp)
 833		return ERR_PTR(-ENOENT);
 834
 835	key.ex_client = clp;
 836	key.ex_path = *path;
 837	key.cd = cd;
 838
 839	exp = svc_export_lookup(&key);
 840	if (exp == NULL)
 841		return ERR_PTR(-ENOMEM);
 842	err = cache_check(cd, &exp->h, reqp);
 843	if (err)
 844		return ERR_PTR(err);
 845	return exp;
 846}
 847
 848/*
 849 * Find the export entry for a given dentry.
 850 */
 851static struct svc_export *
 852exp_parent(struct cache_detail *cd, struct auth_domain *clp, struct path *path)
 853{
 854	struct dentry *saved = dget(path->dentry);
 855	struct svc_export *exp = exp_get_by_name(cd, clp, path, NULL);
 856
 857	while (PTR_ERR(exp) == -ENOENT && !IS_ROOT(path->dentry)) {
 858		struct dentry *parent = dget_parent(path->dentry);
 859		dput(path->dentry);
 860		path->dentry = parent;
 861		exp = exp_get_by_name(cd, clp, path, NULL);
 862	}
 863	dput(path->dentry);
 864	path->dentry = saved;
 865	return exp;
 866}
 867
 868
 869
 870/*
 871 * Obtain the root fh on behalf of a client.
 872 * This could be done in user space, but I feel that it adds some safety
 873 * since its harder to fool a kernel module than a user space program.
 874 */
 875int
 876exp_rootfh(struct net *net, struct auth_domain *clp, char *name,
 877	   struct knfsd_fh *f, int maxsize)
 878{
 879	struct svc_export	*exp;
 880	struct path		path;
 881	struct inode		*inode;
 882	struct svc_fh		fh;
 883	int			err;
 884	struct nfsd_net		*nn = net_generic(net, nfsd_net_id);
 885	struct cache_detail	*cd = nn->svc_export_cache;
 886
 887	err = -EPERM;
 888	/* NB: we probably ought to check that it's NUL-terminated */
 889	if (kern_path(name, 0, &path)) {
 890		printk("nfsd: exp_rootfh path not found %s", name);
 891		return err;
 892	}
 893	inode = d_inode(path.dentry);
 894
 895	dprintk("nfsd: exp_rootfh(%s [%p] %s:%s/%ld)\n",
 896		 name, path.dentry, clp->name,
 897		 inode->i_sb->s_id, inode->i_ino);
 898	exp = exp_parent(cd, clp, &path);
 899	if (IS_ERR(exp)) {
 900		err = PTR_ERR(exp);
 901		goto out;
 902	}
 903
 904	/*
 905	 * fh must be initialized before calling fh_compose
 906	 */
 907	fh_init(&fh, maxsize);
 908	if (fh_compose(&fh, exp, path.dentry, NULL))
 909		err = -EINVAL;
 910	else
 911		err = 0;
 912	memcpy(f, &fh.fh_handle, sizeof(struct knfsd_fh));
 913	fh_put(&fh);
 914	exp_put(exp);
 915out:
 916	path_put(&path);
 917	return err;
 918}
 919
 920static struct svc_export *exp_find(struct cache_detail *cd,
 921				   struct auth_domain *clp, int fsid_type,
 922				   u32 *fsidv, struct cache_req *reqp)
 923{
 924	struct svc_export *exp;
 925	struct nfsd_net *nn = net_generic(cd->net, nfsd_net_id);
 926	struct svc_expkey *ek = exp_find_key(nn->svc_expkey_cache, clp, fsid_type, fsidv, reqp);
 927	if (IS_ERR(ek))
 928		return ERR_CAST(ek);
 929
 930	exp = exp_get_by_name(cd, clp, &ek->ek_path, reqp);
 931	cache_put(&ek->h, nn->svc_expkey_cache);
 932
 933	if (IS_ERR(exp))
 934		return ERR_CAST(exp);
 935	return exp;
 936}
 937
 938__be32 check_nfsd_access(struct svc_export *exp, struct svc_rqst *rqstp)
 939{
 940	struct exp_flavor_info *f;
 941	struct exp_flavor_info *end = exp->ex_flavors + exp->ex_nflavors;
 942
 943	/* legacy gss-only clients are always OK: */
 944	if (exp->ex_client == rqstp->rq_gssclient)
 945		return 0;
 946	/* ip-address based client; check sec= export option: */
 947	for (f = exp->ex_flavors; f < end; f++) {
 948		if (f->pseudoflavor == rqstp->rq_cred.cr_flavor)
 949			return 0;
 950	}
 951	/* defaults in absence of sec= options: */
 952	if (exp->ex_nflavors == 0) {
 953		if (rqstp->rq_cred.cr_flavor == RPC_AUTH_NULL ||
 954		    rqstp->rq_cred.cr_flavor == RPC_AUTH_UNIX)
 955			return 0;
 956	}
 
 
 
 
 
 
 
 
 
 
 957	return nfserr_wrongsec;
 958}
 959
 960/*
 961 * Uses rq_client and rq_gssclient to find an export; uses rq_client (an
 962 * auth_unix client) if it's available and has secinfo information;
 963 * otherwise, will try to use rq_gssclient.
 964 *
 965 * Called from functions that handle requests; functions that do work on
 966 * behalf of mountd are passed a single client name to use, and should
 967 * use exp_get_by_name() or exp_find().
 968 */
 969struct svc_export *
 970rqst_exp_get_by_name(struct svc_rqst *rqstp, struct path *path)
 971{
 972	struct svc_export *gssexp, *exp = ERR_PTR(-ENOENT);
 973	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
 974	struct cache_detail *cd = nn->svc_export_cache;
 975
 976	if (rqstp->rq_client == NULL)
 977		goto gss;
 978
 979	/* First try the auth_unix client: */
 980	exp = exp_get_by_name(cd, rqstp->rq_client, path, &rqstp->rq_chandle);
 981	if (PTR_ERR(exp) == -ENOENT)
 982		goto gss;
 983	if (IS_ERR(exp))
 984		return exp;
 985	/* If it has secinfo, assume there are no gss/... clients */
 986	if (exp->ex_nflavors > 0)
 987		return exp;
 988gss:
 989	/* Otherwise, try falling back on gss client */
 990	if (rqstp->rq_gssclient == NULL)
 991		return exp;
 992	gssexp = exp_get_by_name(cd, rqstp->rq_gssclient, path, &rqstp->rq_chandle);
 993	if (PTR_ERR(gssexp) == -ENOENT)
 994		return exp;
 995	if (!IS_ERR(exp))
 996		exp_put(exp);
 997	return gssexp;
 998}
 999
1000struct svc_export *
1001rqst_exp_find(struct svc_rqst *rqstp, int fsid_type, u32 *fsidv)
1002{
1003	struct svc_export *gssexp, *exp = ERR_PTR(-ENOENT);
1004	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
1005	struct cache_detail *cd = nn->svc_export_cache;
1006
1007	if (rqstp->rq_client == NULL)
1008		goto gss;
1009
1010	/* First try the auth_unix client: */
1011	exp = exp_find(cd, rqstp->rq_client, fsid_type,
1012		       fsidv, &rqstp->rq_chandle);
1013	if (PTR_ERR(exp) == -ENOENT)
1014		goto gss;
1015	if (IS_ERR(exp))
1016		return exp;
1017	/* If it has secinfo, assume there are no gss/... clients */
1018	if (exp->ex_nflavors > 0)
1019		return exp;
1020gss:
1021	/* Otherwise, try falling back on gss client */
1022	if (rqstp->rq_gssclient == NULL)
1023		return exp;
1024	gssexp = exp_find(cd, rqstp->rq_gssclient, fsid_type, fsidv,
1025						&rqstp->rq_chandle);
1026	if (PTR_ERR(gssexp) == -ENOENT)
1027		return exp;
1028	if (!IS_ERR(exp))
1029		exp_put(exp);
1030	return gssexp;
1031}
1032
1033struct svc_export *
1034rqst_exp_parent(struct svc_rqst *rqstp, struct path *path)
1035{
1036	struct dentry *saved = dget(path->dentry);
1037	struct svc_export *exp = rqst_exp_get_by_name(rqstp, path);
1038
1039	while (PTR_ERR(exp) == -ENOENT && !IS_ROOT(path->dentry)) {
1040		struct dentry *parent = dget_parent(path->dentry);
1041		dput(path->dentry);
1042		path->dentry = parent;
1043		exp = rqst_exp_get_by_name(rqstp, path);
1044	}
1045	dput(path->dentry);
1046	path->dentry = saved;
1047	return exp;
1048}
1049
1050struct svc_export *rqst_find_fsidzero_export(struct svc_rqst *rqstp)
1051{
1052	u32 fsidv[2];
1053
1054	mk_fsid(FSID_NUM, fsidv, 0, 0, 0, NULL);
1055
1056	return rqst_exp_find(rqstp, FSID_NUM, fsidv);
1057}
1058
1059/*
1060 * Called when we need the filehandle for the root of the pseudofs,
1061 * for a given NFSv4 client.   The root is defined to be the
1062 * export point with fsid==0
1063 */
1064__be32
1065exp_pseudoroot(struct svc_rqst *rqstp, struct svc_fh *fhp)
1066{
1067	struct svc_export *exp;
1068	__be32 rv;
1069
1070	exp = rqst_find_fsidzero_export(rqstp);
1071	if (IS_ERR(exp))
1072		return nfserrno(PTR_ERR(exp));
1073	rv = fh_compose(fhp, exp, exp->ex_path.dentry, NULL);
1074	exp_put(exp);
1075	return rv;
1076}
1077
1078static struct flags {
1079	int flag;
1080	char *name[2];
1081} expflags[] = {
1082	{ NFSEXP_READONLY, {"ro", "rw"}},
1083	{ NFSEXP_INSECURE_PORT, {"insecure", ""}},
1084	{ NFSEXP_ROOTSQUASH, {"root_squash", "no_root_squash"}},
1085	{ NFSEXP_ALLSQUASH, {"all_squash", ""}},
1086	{ NFSEXP_ASYNC, {"async", "sync"}},
1087	{ NFSEXP_GATHERED_WRITES, {"wdelay", "no_wdelay"}},
1088	{ NFSEXP_NOREADDIRPLUS, {"nordirplus", ""}},
1089	{ NFSEXP_NOHIDE, {"nohide", ""}},
1090	{ NFSEXP_CROSSMOUNT, {"crossmnt", ""}},
1091	{ NFSEXP_NOSUBTREECHECK, {"no_subtree_check", ""}},
1092	{ NFSEXP_NOAUTHNLM, {"insecure_locks", ""}},
1093	{ NFSEXP_V4ROOT, {"v4root", ""}},
1094	{ NFSEXP_PNFS, {"pnfs", ""}},
1095	{ 0, {"", ""}}
1096};
1097
1098static void show_expflags(struct seq_file *m, int flags, int mask)
1099{
1100	struct flags *flg;
1101	int state, first = 0;
1102
1103	for (flg = expflags; flg->flag; flg++) {
1104		if (flg->flag & ~mask)
1105			continue;
1106		state = (flg->flag & flags) ? 0 : 1;
1107		if (*flg->name[state])
1108			seq_printf(m, "%s%s", first++?",":"", flg->name[state]);
1109	}
1110}
1111
1112static void show_secinfo_flags(struct seq_file *m, int flags)
1113{
1114	seq_printf(m, ",");
1115	show_expflags(m, flags, NFSEXP_SECINFO_FLAGS);
1116}
1117
1118static bool secinfo_flags_equal(int f, int g)
1119{
1120	f &= NFSEXP_SECINFO_FLAGS;
1121	g &= NFSEXP_SECINFO_FLAGS;
1122	return f == g;
1123}
1124
1125static int show_secinfo_run(struct seq_file *m, struct exp_flavor_info **fp, struct exp_flavor_info *end)
1126{
1127	int flags;
1128
1129	flags = (*fp)->flags;
1130	seq_printf(m, ",sec=%d", (*fp)->pseudoflavor);
1131	(*fp)++;
1132	while (*fp != end && secinfo_flags_equal(flags, (*fp)->flags)) {
1133		seq_printf(m, ":%d", (*fp)->pseudoflavor);
1134		(*fp)++;
1135	}
1136	return flags;
1137}
1138
1139static void show_secinfo(struct seq_file *m, struct svc_export *exp)
1140{
1141	struct exp_flavor_info *f;
1142	struct exp_flavor_info *end = exp->ex_flavors + exp->ex_nflavors;
1143	int flags;
1144
1145	if (exp->ex_nflavors == 0)
1146		return;
1147	f = exp->ex_flavors;
1148	flags = show_secinfo_run(m, &f, end);
1149	if (!secinfo_flags_equal(flags, exp->ex_flags))
1150		show_secinfo_flags(m, flags);
1151	while (f != end) {
1152		flags = show_secinfo_run(m, &f, end);
1153		show_secinfo_flags(m, flags);
1154	}
1155}
1156
1157static void exp_flags(struct seq_file *m, int flag, int fsid,
1158		kuid_t anonu, kgid_t anong, struct nfsd4_fs_locations *fsloc)
1159{
1160	show_expflags(m, flag, NFSEXP_ALLFLAGS);
1161	if (flag & NFSEXP_FSID)
1162		seq_printf(m, ",fsid=%d", fsid);
1163	if (!uid_eq(anonu, make_kuid(&init_user_ns, (uid_t)-2)) &&
1164	    !uid_eq(anonu, make_kuid(&init_user_ns, 0x10000-2)))
1165		seq_printf(m, ",anonuid=%u", from_kuid(&init_user_ns, anonu));
1166	if (!gid_eq(anong, make_kgid(&init_user_ns, (gid_t)-2)) &&
1167	    !gid_eq(anong, make_kgid(&init_user_ns, 0x10000-2)))
1168		seq_printf(m, ",anongid=%u", from_kgid(&init_user_ns, anong));
1169	if (fsloc && fsloc->locations_count > 0) {
1170		char *loctype = (fsloc->migrated) ? "refer" : "replicas";
1171		int i;
1172
1173		seq_printf(m, ",%s=", loctype);
1174		seq_escape(m, fsloc->locations[0].path, ",;@ \t\n\\");
1175		seq_putc(m, '@');
1176		seq_escape(m, fsloc->locations[0].hosts, ",;@ \t\n\\");
1177		for (i = 1; i < fsloc->locations_count; i++) {
1178			seq_putc(m, ';');
1179			seq_escape(m, fsloc->locations[i].path, ",;@ \t\n\\");
1180			seq_putc(m, '@');
1181			seq_escape(m, fsloc->locations[i].hosts, ",;@ \t\n\\");
1182		}
1183	}
1184}
1185
1186static int e_show(struct seq_file *m, void *p)
1187{
1188	struct cache_head *cp = p;
1189	struct svc_export *exp = container_of(cp, struct svc_export, h);
1190	struct cache_detail *cd = m->private;
1191
1192	if (p == SEQ_START_TOKEN) {
1193		seq_puts(m, "# Version 1.1\n");
1194		seq_puts(m, "# Path Client(Flags) # IPs\n");
1195		return 0;
1196	}
1197
1198	exp_get(exp);
1199	if (cache_check(cd, &exp->h, NULL))
1200		return 0;
1201	exp_put(exp);
1202	return svc_export_show(m, cd, cp);
1203}
1204
1205const struct seq_operations nfs_exports_op = {
1206	.start	= cache_seq_start,
1207	.next	= cache_seq_next,
1208	.stop	= cache_seq_stop,
1209	.show	= e_show,
1210};
1211
1212/*
1213 * Initialize the exports module.
1214 */
1215int
1216nfsd_export_init(struct net *net)
1217{
1218	int rv;
1219	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
1220
1221	dprintk("nfsd: initializing export module (net: %p).\n", net);
1222
1223	nn->svc_export_cache = cache_create_net(&svc_export_cache_template, net);
1224	if (IS_ERR(nn->svc_export_cache))
1225		return PTR_ERR(nn->svc_export_cache);
1226	rv = cache_register_net(nn->svc_export_cache, net);
1227	if (rv)
1228		goto destroy_export_cache;
1229
1230	nn->svc_expkey_cache = cache_create_net(&svc_expkey_cache_template, net);
1231	if (IS_ERR(nn->svc_expkey_cache)) {
1232		rv = PTR_ERR(nn->svc_expkey_cache);
1233		goto unregister_export_cache;
1234	}
1235	rv = cache_register_net(nn->svc_expkey_cache, net);
1236	if (rv)
1237		goto destroy_expkey_cache;
1238	return 0;
1239
1240destroy_expkey_cache:
1241	cache_destroy_net(nn->svc_expkey_cache, net);
1242unregister_export_cache:
1243	cache_unregister_net(nn->svc_export_cache, net);
1244destroy_export_cache:
1245	cache_destroy_net(nn->svc_export_cache, net);
1246	return rv;
1247}
1248
1249/*
1250 * Flush exports table - called when last nfsd thread is killed
1251 */
1252void
1253nfsd_export_flush(struct net *net)
1254{
1255	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
1256
1257	cache_purge(nn->svc_expkey_cache);
1258	cache_purge(nn->svc_export_cache);
1259}
1260
1261/*
1262 * Shutdown the exports module.
1263 */
1264void
1265nfsd_export_shutdown(struct net *net)
1266{
1267	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
1268
1269	dprintk("nfsd: shutting down export module (net: %p).\n", net);
1270
1271	cache_unregister_net(nn->svc_expkey_cache, net);
1272	cache_unregister_net(nn->svc_export_cache, net);
1273	cache_destroy_net(nn->svc_expkey_cache, net);
1274	cache_destroy_net(nn->svc_export_cache, net);
1275	svcauth_unix_purge(net);
1276
1277	dprintk("nfsd: export shutdown complete (net: %p).\n", net);
1278}