1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* /proc interface for AFS 3 * 4 * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved. 5 * Written by David Howells (dhowells@redhat.com) 6 */ 7 8 #include <linux/slab.h> 9 #include <linux/module.h> 10 #include <linux/proc_fs.h> 11 #include <linux/seq_file.h> 12 #include <linux/sched.h> 13 #include <linux/uaccess.h> 14 #include "internal.h" 15 16 struct afs_vl_seq_net_private { 17 struct seq_net_private seq; /* Must be first */ 18 struct afs_vlserver_list *vllist; 19 }; 20 21 static inline struct afs_net *afs_seq2net(struct seq_file *m) 22 { 23 return afs_net(seq_file_net(m)); 24 } 25 26 static inline struct afs_net *afs_seq2net_single(struct seq_file *m) 27 { 28 return afs_net(seq_file_single_net(m)); 29 } 30 31 /* 32 * Display the list of cells known to the namespace. 33 */ 34 static int afs_proc_cells_show(struct seq_file *m, void *v) 35 { 36 struct afs_vlserver_list *vllist; 37 struct afs_cell *cell; 38 39 if (v == SEQ_START_TOKEN) { 40 /* display header on line 1 */ 41 seq_puts(m, "USE TTL SV NAME\n"); 42 return 0; 43 } 44 45 cell = list_entry(v, struct afs_cell, proc_link); 46 vllist = rcu_dereference(cell->vl_servers); 47 48 /* display one cell per line on subsequent lines */ 49 seq_printf(m, "%3u %6lld %2u %s\n", 50 atomic_read(&cell->usage), 51 cell->dns_expiry - ktime_get_real_seconds(), 52 vllist->nr_servers, 53 cell->name); 54 return 0; 55 } 56 57 static void *afs_proc_cells_start(struct seq_file *m, loff_t *_pos) 58 __acquires(rcu) 59 { 60 rcu_read_lock(); 61 return seq_hlist_start_head_rcu(&afs_seq2net(m)->proc_cells, *_pos); 62 } 63 64 static void *afs_proc_cells_next(struct seq_file *m, void *v, loff_t *pos) 65 { 66 return seq_hlist_next_rcu(v, &afs_seq2net(m)->proc_cells, pos); 67 } 68 69 static void afs_proc_cells_stop(struct seq_file *m, void *v) 70 __releases(rcu) 71 { 72 rcu_read_unlock(); 73 } 74 75 static const struct seq_operations afs_proc_cells_ops = { 76 .start = afs_proc_cells_start, 77 .next = afs_proc_cells_next, 78 .stop = afs_proc_cells_stop, 79 .show = afs_proc_cells_show, 80 }; 81 82 /* 83 * handle writes to /proc/fs/afs/cells 84 * - to add cells: echo "add <cellname> <IP>[:<IP>][:<IP>]" 85 */ 86 static int afs_proc_cells_write(struct file *file, char *buf, size_t size) 87 { 88 struct seq_file *m = file->private_data; 89 struct afs_net *net = afs_seq2net(m); 90 char *name, *args; 91 int ret; 92 93 /* trim to first NL */ 94 name = memchr(buf, '\n', size); 95 if (name) 96 *name = 0; 97 98 /* split into command, name and argslist */ 99 name = strchr(buf, ' '); 100 if (!name) 101 goto inval; 102 do { 103 *name++ = 0; 104 } while(*name == ' '); 105 if (!*name) 106 goto inval; 107 108 args = strchr(name, ' '); 109 if (args) { 110 do { 111 *args++ = 0; 112 } while(*args == ' '); 113 if (!*args) 114 goto inval; 115 } 116 117 /* determine command to perform */ 118 _debug("cmd=%s name=%s args=%s", buf, name, args); 119 120 if (strcmp(buf, "add") == 0) { 121 struct afs_cell *cell; 122 123 cell = afs_lookup_cell(net, name, strlen(name), args, true); 124 if (IS_ERR(cell)) { 125 ret = PTR_ERR(cell); 126 goto done; 127 } 128 129 if (test_and_set_bit(AFS_CELL_FL_NO_GC, &cell->flags)) 130 afs_put_cell(net, cell); 131 } else { 132 goto inval; 133 } 134 135 ret = 0; 136 137 done: 138 _leave(" = %d", ret); 139 return ret; 140 141 inval: 142 ret = -EINVAL; 143 printk("kAFS: Invalid Command on /proc/fs/afs/cells file\n"); 144 goto done; 145 } 146 147 /* 148 * Display the name of the current workstation cell. 149 */ 150 static int afs_proc_rootcell_show(struct seq_file *m, void *v) 151 { 152 struct afs_cell *cell; 153 struct afs_net *net; 154 155 net = afs_seq2net_single(m); 156 if (rcu_access_pointer(net->ws_cell)) { 157 rcu_read_lock(); 158 cell = rcu_dereference(net->ws_cell); 159 if (cell) 160 seq_printf(m, "%s\n", cell->name); 161 rcu_read_unlock(); 162 } 163 return 0; 164 } 165 166 /* 167 * Set the current workstation cell and optionally supply its list of volume 168 * location servers. 169 * 170 * echo "cell.name:192.168.231.14" >/proc/fs/afs/rootcell 171 */ 172 static int afs_proc_rootcell_write(struct file *file, char *buf, size_t size) 173 { 174 struct seq_file *m = file->private_data; 175 struct afs_net *net = afs_seq2net_single(m); 176 char *s; 177 int ret; 178 179 ret = -EINVAL; 180 if (buf[0] == '.') 181 goto out; 182 if (memchr(buf, '/', size)) 183 goto out; 184 185 /* trim to first NL */ 186 s = memchr(buf, '\n', size); 187 if (s) 188 *s = 0; 189 190 /* determine command to perform */ 191 _debug("rootcell=%s", buf); 192 193 ret = afs_cell_init(net, buf); 194 195 out: 196 _leave(" = %d", ret); 197 return ret; 198 } 199 200 static const char afs_vol_types[3][3] = { 201 [AFSVL_RWVOL] = "RW", 202 [AFSVL_ROVOL] = "RO", 203 [AFSVL_BACKVOL] = "BK", 204 }; 205 206 /* 207 * Display the list of volumes known to a cell. 208 */ 209 static int afs_proc_cell_volumes_show(struct seq_file *m, void *v) 210 { 211 struct afs_cell *cell = PDE_DATA(file_inode(m->file)); 212 struct afs_volume *vol = list_entry(v, struct afs_volume, proc_link); 213 214 /* Display header on line 1 */ 215 if (v == &cell->proc_volumes) { 216 seq_puts(m, "USE VID TY\n"); 217 return 0; 218 } 219 220 seq_printf(m, "%3d %08llx %s\n", 221 atomic_read(&vol->usage), vol->vid, 222 afs_vol_types[vol->type]); 223 224 return 0; 225 } 226 227 static void *afs_proc_cell_volumes_start(struct seq_file *m, loff_t *_pos) 228 __acquires(cell->proc_lock) 229 { 230 struct afs_cell *cell = PDE_DATA(file_inode(m->file)); 231 232 read_lock(&cell->proc_lock); 233 return seq_list_start_head(&cell->proc_volumes, *_pos); 234 } 235 236 static void *afs_proc_cell_volumes_next(struct seq_file *m, void *v, 237 loff_t *_pos) 238 { 239 struct afs_cell *cell = PDE_DATA(file_inode(m->file)); 240 241 return seq_list_next(v, &cell->proc_volumes, _pos); 242 } 243 244 static void afs_proc_cell_volumes_stop(struct seq_file *m, void *v) 245 __releases(cell->proc_lock) 246 { 247 struct afs_cell *cell = PDE_DATA(file_inode(m->file)); 248 249 read_unlock(&cell->proc_lock); 250 } 251 252 static const struct seq_operations afs_proc_cell_volumes_ops = { 253 .start = afs_proc_cell_volumes_start, 254 .next = afs_proc_cell_volumes_next, 255 .stop = afs_proc_cell_volumes_stop, 256 .show = afs_proc_cell_volumes_show, 257 }; 258 259 static const char *const dns_record_sources[NR__dns_record_source + 1] = { 260 [DNS_RECORD_UNAVAILABLE] = "unav", 261 [DNS_RECORD_FROM_CONFIG] = "cfg", 262 [DNS_RECORD_FROM_DNS_A] = "A", 263 [DNS_RECORD_FROM_DNS_AFSDB] = "AFSDB", 264 [DNS_RECORD_FROM_DNS_SRV] = "SRV", 265 [DNS_RECORD_FROM_NSS] = "nss", 266 [NR__dns_record_source] = "[weird]" 267 }; 268 269 static const char *const dns_lookup_statuses[NR__dns_lookup_status + 1] = { 270 [DNS_LOOKUP_NOT_DONE] = "no-lookup", 271 [DNS_LOOKUP_GOOD] = "good", 272 [DNS_LOOKUP_GOOD_WITH_BAD] = "good/bad", 273 [DNS_LOOKUP_BAD] = "bad", 274 [DNS_LOOKUP_GOT_NOT_FOUND] = "not-found", 275 [DNS_LOOKUP_GOT_LOCAL_FAILURE] = "local-failure", 276 [DNS_LOOKUP_GOT_TEMP_FAILURE] = "temp-failure", 277 [DNS_LOOKUP_GOT_NS_FAILURE] = "ns-failure", 278 [NR__dns_lookup_status] = "[weird]" 279 }; 280 281 /* 282 * Display the list of Volume Location servers we're using for a cell. 283 */ 284 static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v) 285 { 286 const struct afs_vl_seq_net_private *priv = m->private; 287 const struct afs_vlserver_list *vllist = priv->vllist; 288 const struct afs_vlserver_entry *entry; 289 const struct afs_vlserver *vlserver; 290 const struct afs_addr_list *alist; 291 int i; 292 293 if (v == SEQ_START_TOKEN) { 294 seq_printf(m, "# source %s, status %s\n", 295 dns_record_sources[vllist ? vllist->source : 0], 296 dns_lookup_statuses[vllist ? vllist->status : 0]); 297 return 0; 298 } 299 300 entry = v; 301 vlserver = entry->server; 302 alist = rcu_dereference(vlserver->addresses); 303 304 seq_printf(m, "%s [p=%hu w=%hu s=%s,%s]:\n", 305 vlserver->name, entry->priority, entry->weight, 306 dns_record_sources[alist ? alist->source : entry->source], 307 dns_lookup_statuses[alist ? alist->status : entry->status]); 308 if (alist) { 309 for (i = 0; i < alist->nr_addrs; i++) 310 seq_printf(m, " %c %pISpc\n", 311 alist->preferred == i ? '>' : '-', 312 &alist->addrs[i].transport); 313 } 314 return 0; 315 } 316 317 static void *afs_proc_cell_vlservers_start(struct seq_file *m, loff_t *_pos) 318 __acquires(rcu) 319 { 320 struct afs_vl_seq_net_private *priv = m->private; 321 struct afs_vlserver_list *vllist; 322 struct afs_cell *cell = PDE_DATA(file_inode(m->file)); 323 loff_t pos = *_pos; 324 325 rcu_read_lock(); 326 327 vllist = rcu_dereference(cell->vl_servers); 328 priv->vllist = vllist; 329 330 if (pos < 0) 331 *_pos = pos = 0; 332 if (pos == 0) 333 return SEQ_START_TOKEN; 334 335 if (pos - 1 >= vllist->nr_servers) 336 return NULL; 337 338 return &vllist->servers[pos - 1]; 339 } 340 341 static void *afs_proc_cell_vlservers_next(struct seq_file *m, void *v, 342 loff_t *_pos) 343 { 344 struct afs_vl_seq_net_private *priv = m->private; 345 struct afs_vlserver_list *vllist = priv->vllist; 346 loff_t pos; 347 348 pos = *_pos; 349 pos++; 350 *_pos = pos; 351 if (!vllist || pos - 1 >= vllist->nr_servers) 352 return NULL; 353 354 return &vllist->servers[pos - 1]; 355 } 356 357 static void afs_proc_cell_vlservers_stop(struct seq_file *m, void *v) 358 __releases(rcu) 359 { 360 rcu_read_unlock(); 361 } 362 363 static const struct seq_operations afs_proc_cell_vlservers_ops = { 364 .start = afs_proc_cell_vlservers_start, 365 .next = afs_proc_cell_vlservers_next, 366 .stop = afs_proc_cell_vlservers_stop, 367 .show = afs_proc_cell_vlservers_show, 368 }; 369 370 /* 371 * Display the list of fileservers we're using within a namespace. 372 */ 373 static int afs_proc_servers_show(struct seq_file *m, void *v) 374 { 375 struct afs_server *server; 376 struct afs_addr_list *alist; 377 int i; 378 379 if (v == SEQ_START_TOKEN) { 380 seq_puts(m, "UUID USE ADDR\n"); 381 return 0; 382 } 383 384 server = list_entry(v, struct afs_server, proc_link); 385 alist = rcu_dereference(server->addresses); 386 seq_printf(m, "%pU %3d %pISpc%s\n", 387 &server->uuid, 388 atomic_read(&server->usage), 389 &alist->addrs[0].transport, 390 alist->preferred == 0 ? "*" : ""); 391 for (i = 1; i < alist->nr_addrs; i++) 392 seq_printf(m, " %pISpc%s\n", 393 &alist->addrs[i].transport, 394 alist->preferred == i ? "*" : ""); 395 return 0; 396 } 397 398 static void *afs_proc_servers_start(struct seq_file *m, loff_t *_pos) 399 __acquires(rcu) 400 { 401 rcu_read_lock(); 402 return seq_hlist_start_head_rcu(&afs_seq2net(m)->fs_proc, *_pos); 403 } 404 405 static void *afs_proc_servers_next(struct seq_file *m, void *v, loff_t *_pos) 406 { 407 return seq_hlist_next_rcu(v, &afs_seq2net(m)->fs_proc, _pos); 408 } 409 410 static void afs_proc_servers_stop(struct seq_file *m, void *v) 411 __releases(rcu) 412 { 413 rcu_read_unlock(); 414 } 415 416 static const struct seq_operations afs_proc_servers_ops = { 417 .start = afs_proc_servers_start, 418 .next = afs_proc_servers_next, 419 .stop = afs_proc_servers_stop, 420 .show = afs_proc_servers_show, 421 }; 422 423 /* 424 * Display the list of strings that may be substituted for the @sys pathname 425 * macro. 426 */ 427 static int afs_proc_sysname_show(struct seq_file *m, void *v) 428 { 429 struct afs_net *net = afs_seq2net(m); 430 struct afs_sysnames *sysnames = net->sysnames; 431 unsigned int i = (unsigned long)v - 1; 432 433 if (i < sysnames->nr) 434 seq_printf(m, "%s\n", sysnames->subs[i]); 435 return 0; 436 } 437 438 static void *afs_proc_sysname_start(struct seq_file *m, loff_t *pos) 439 __acquires(&net->sysnames_lock) 440 { 441 struct afs_net *net = afs_seq2net(m); 442 struct afs_sysnames *names; 443 444 read_lock(&net->sysnames_lock); 445 446 names = net->sysnames; 447 if (*pos >= names->nr) 448 return NULL; 449 return (void *)(unsigned long)(*pos + 1); 450 } 451 452 static void *afs_proc_sysname_next(struct seq_file *m, void *v, loff_t *pos) 453 { 454 struct afs_net *net = afs_seq2net(m); 455 struct afs_sysnames *names = net->sysnames; 456 457 *pos += 1; 458 if (*pos >= names->nr) 459 return NULL; 460 return (void *)(unsigned long)(*pos + 1); 461 } 462 463 static void afs_proc_sysname_stop(struct seq_file *m, void *v) 464 __releases(&net->sysnames_lock) 465 { 466 struct afs_net *net = afs_seq2net(m); 467 468 read_unlock(&net->sysnames_lock); 469 } 470 471 static const struct seq_operations afs_proc_sysname_ops = { 472 .start = afs_proc_sysname_start, 473 .next = afs_proc_sysname_next, 474 .stop = afs_proc_sysname_stop, 475 .show = afs_proc_sysname_show, 476 }; 477 478 /* 479 * Allow the @sys substitution to be configured. 480 */ 481 static int afs_proc_sysname_write(struct file *file, char *buf, size_t size) 482 { 483 struct afs_sysnames *sysnames, *kill; 484 struct seq_file *m = file->private_data; 485 struct afs_net *net = afs_seq2net(m); 486 char *s, *p, *sub; 487 int ret, len; 488 489 sysnames = kzalloc(sizeof(*sysnames), GFP_KERNEL); 490 if (!sysnames) 491 return -ENOMEM; 492 refcount_set(&sysnames->usage, 1); 493 kill = sysnames; 494 495 p = buf; 496 while ((s = strsep(&p, " \t\n"))) { 497 len = strlen(s); 498 if (len == 0) 499 continue; 500 ret = -ENAMETOOLONG; 501 if (len >= AFSNAMEMAX) 502 goto error; 503 504 if (len >= 4 && 505 s[len - 4] == '@' && 506 s[len - 3] == 's' && 507 s[len - 2] == 'y' && 508 s[len - 1] == 's') 509 /* Protect against recursion */ 510 goto invalid; 511 512 if (s[0] == '.' && 513 (len < 2 || (len == 2 && s[1] == '.'))) 514 goto invalid; 515 516 if (memchr(s, '/', len)) 517 goto invalid; 518 519 ret = -EFBIG; 520 if (sysnames->nr >= AFS_NR_SYSNAME) 521 goto out; 522 523 if (strcmp(s, afs_init_sysname) == 0) { 524 sub = (char *)afs_init_sysname; 525 } else { 526 ret = -ENOMEM; 527 sub = kmemdup(s, len + 1, GFP_KERNEL); 528 if (!sub) 529 goto out; 530 } 531 532 sysnames->subs[sysnames->nr] = sub; 533 sysnames->nr++; 534 } 535 536 if (sysnames->nr == 0) { 537 sysnames->subs[0] = sysnames->blank; 538 sysnames->nr++; 539 } 540 541 write_lock(&net->sysnames_lock); 542 kill = net->sysnames; 543 net->sysnames = sysnames; 544 write_unlock(&net->sysnames_lock); 545 ret = 0; 546 out: 547 afs_put_sysnames(kill); 548 return ret; 549 550 invalid: 551 ret = -EINVAL; 552 error: 553 goto out; 554 } 555 556 void afs_put_sysnames(struct afs_sysnames *sysnames) 557 { 558 int i; 559 560 if (sysnames && refcount_dec_and_test(&sysnames->usage)) { 561 for (i = 0; i < sysnames->nr; i++) 562 if (sysnames->subs[i] != afs_init_sysname && 563 sysnames->subs[i] != sysnames->blank) 564 kfree(sysnames->subs[i]); 565 } 566 } 567 568 /* 569 * Display general per-net namespace statistics 570 */ 571 static int afs_proc_stats_show(struct seq_file *m, void *v) 572 { 573 struct afs_net *net = afs_seq2net_single(m); 574 575 seq_puts(m, "kAFS statistics\n"); 576 577 seq_printf(m, "dir-mgmt: look=%u reval=%u inval=%u relpg=%u\n", 578 atomic_read(&net->n_lookup), 579 atomic_read(&net->n_reval), 580 atomic_read(&net->n_inval), 581 atomic_read(&net->n_relpg)); 582 583 seq_printf(m, "dir-data: rdpg=%u\n", 584 atomic_read(&net->n_read_dir)); 585 586 seq_printf(m, "dir-edit: cr=%u rm=%u\n", 587 atomic_read(&net->n_dir_cr), 588 atomic_read(&net->n_dir_rm)); 589 590 seq_printf(m, "file-rd : n=%u nb=%lu\n", 591 atomic_read(&net->n_fetches), 592 atomic_long_read(&net->n_fetch_bytes)); 593 seq_printf(m, "file-wr : n=%u nb=%lu\n", 594 atomic_read(&net->n_stores), 595 atomic_long_read(&net->n_store_bytes)); 596 return 0; 597 } 598 599 /* 600 * initialise /proc/fs/afs/<cell>/ 601 */ 602 int afs_proc_cell_setup(struct afs_cell *cell) 603 { 604 struct proc_dir_entry *dir; 605 struct afs_net *net = cell->net; 606 607 _enter("%p{%s},%p", cell, cell->name, net->proc_afs); 608 609 dir = proc_net_mkdir(net->net, cell->name, net->proc_afs); 610 if (!dir) 611 goto error_dir; 612 613 if (!proc_create_net_data("vlservers", 0444, dir, 614 &afs_proc_cell_vlservers_ops, 615 sizeof(struct afs_vl_seq_net_private), 616 cell) || 617 !proc_create_net_data("volumes", 0444, dir, 618 &afs_proc_cell_volumes_ops, 619 sizeof(struct seq_net_private), 620 cell)) 621 goto error_tree; 622 623 _leave(" = 0"); 624 return 0; 625 626 error_tree: 627 remove_proc_subtree(cell->name, net->proc_afs); 628 error_dir: 629 _leave(" = -ENOMEM"); 630 return -ENOMEM; 631 } 632 633 /* 634 * remove /proc/fs/afs/<cell>/ 635 */ 636 void afs_proc_cell_remove(struct afs_cell *cell) 637 { 638 struct afs_net *net = cell->net; 639 640 _enter(""); 641 remove_proc_subtree(cell->name, net->proc_afs); 642 _leave(""); 643 } 644 645 /* 646 * initialise the /proc/fs/afs/ directory 647 */ 648 int afs_proc_init(struct afs_net *net) 649 { 650 struct proc_dir_entry *p; 651 652 _enter(""); 653 654 p = proc_net_mkdir(net->net, "afs", net->net->proc_net); 655 if (!p) 656 goto error_dir; 657 658 if (!proc_create_net_data_write("cells", 0644, p, 659 &afs_proc_cells_ops, 660 afs_proc_cells_write, 661 sizeof(struct seq_net_private), 662 NULL) || 663 !proc_create_net_single_write("rootcell", 0644, p, 664 afs_proc_rootcell_show, 665 afs_proc_rootcell_write, 666 NULL) || 667 !proc_create_net("servers", 0444, p, &afs_proc_servers_ops, 668 sizeof(struct seq_net_private)) || 669 !proc_create_net_single("stats", 0444, p, afs_proc_stats_show, NULL) || 670 !proc_create_net_data_write("sysname", 0644, p, 671 &afs_proc_sysname_ops, 672 afs_proc_sysname_write, 673 sizeof(struct seq_net_private), 674 NULL)) 675 goto error_tree; 676 677 net->proc_afs = p; 678 _leave(" = 0"); 679 return 0; 680 681 error_tree: 682 proc_remove(p); 683 error_dir: 684 _leave(" = -ENOMEM"); 685 return -ENOMEM; 686 } 687 688 /* 689 * clean up the /proc/fs/afs/ directory 690 */ 691 void afs_proc_cleanup(struct afs_net *net) 692 { 693 proc_remove(net->proc_afs); 694 net->proc_afs = NULL; 695 } 696