devfs_rule.c revision 125855
1100206Sdd/*- 2100206Sdd * Copyright (c) 2002 Dima Dorfman. 3100206Sdd * All rights reserved. 4100206Sdd * 5100206Sdd * Redistribution and use in source and binary forms, with or without 6100206Sdd * modification, are permitted provided that the following conditions 7100206Sdd * are met: 8100206Sdd * 1. Redistributions of source code must retain the above copyright 9100206Sdd * notice, this list of conditions and the following disclaimer. 10100206Sdd * 2. Redistributions in binary form must reproduce the above copyright 11100206Sdd * notice, this list of conditions and the following disclaimer in the 12100206Sdd * documentation and/or other materials provided with the distribution. 13100206Sdd * 14100206Sdd * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15100206Sdd * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16100206Sdd * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17100206Sdd * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18100206Sdd * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19100206Sdd * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20100206Sdd * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21100206Sdd * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22100206Sdd * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23100206Sdd * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24100206Sdd * SUCH DAMAGE. 25100206Sdd * 26100206Sdd * $FreeBSD: head/sys/fs/devfs/devfs_rule.c 125855 2004-02-15 21:43:08Z phk $ 27100206Sdd */ 28100206Sdd 29100206Sdd/* 30100206Sdd * DEVFS ruleset implementation. 31100206Sdd * 32100206Sdd * A note on terminology: To "run" a rule on a dirent is to take the 33100206Sdd * prescribed action; to "apply" a rule is to check whether it matches 34100206Sdd * a dirent and run if if it does. 35100206Sdd * 36100206Sdd * A note on locking: Only foreign entry points (non-static functions) 37100206Sdd * should deal with locking. Everything else assumes we already hold 38100206Sdd * the required kind of lock. 39100206Sdd * 40100206Sdd * A note on namespace: devfs_rules_* are the non-static functions for 41100206Sdd * the entire "ruleset" subsystem, devfs_rule_* are the static 42100206Sdd * functions that operate on rules, and devfs_ruleset_* are the static 43100206Sdd * functions that operate on rulesets. The line between the last two 44100206Sdd * isn't always clear, but the guideline is still useful. 45100206Sdd * 46100206Sdd * A note on "special" identifiers: Ruleset 0 is the NULL, or empty, 47100206Sdd * ruleset; it cannot be deleted or changed in any way. This may be 48100206Sdd * assumed inside the code; e.g., a ruleset of 0 may be interpeted to 49100206Sdd * mean "no ruleset". The interpretation of rule 0 is 50100206Sdd * command-dependent, but in no case is there a real rule with number 51100206Sdd * 0. 52100206Sdd * 53100206Sdd * A note on errno codes: To make it easier for the userland to tell 54100206Sdd * what went wrong, we sometimes use errno codes that are not entirely 55100206Sdd * appropriate for the error but that would be less ambiguous than the 56100206Sdd * appropriate "generic" code. For example, when we can't find a 57100206Sdd * ruleset, we return ESRCH instead of ENOENT (except in 58100206Sdd * DEVFSIO_{R,S}GETNEXT, where a nonexistent ruleset means "end of 59100206Sdd * list", and the userland expects ENOENT to be this indicator); this 60100206Sdd * way, when an operation fails, it's clear that what couldn't be 61100206Sdd * found is a ruleset and not a rule (well, it's clear to those who 62100206Sdd * know the convention). 63100206Sdd */ 64100206Sdd 65100206Sdd#include "opt_devfs.h" 66100206Sdd 67100206Sdd#include <sys/param.h> 68100206Sdd#include <sys/systm.h> 69100206Sdd#include <sys/conf.h> 70100206Sdd#include <sys/kernel.h> 71100206Sdd#include <sys/malloc.h> 72100206Sdd#include <sys/dirent.h> 73100206Sdd#include <sys/vnode.h> 74100206Sdd#include <sys/mount.h> 75100206Sdd#include <sys/ioccom.h> 76100206Sdd 77100206Sdd#include <fs/devfs/devfs.h> 78100206Sdd 79100206Sdd 80100206Sdd/* 81100206Sdd * Kernel version of devfs_rule. 82100206Sdd */ 83100206Sddstruct devfs_krule { 84100206Sdd SLIST_ENTRY(devfs_krule) dk_list; 85100206Sdd struct devfs_ruleset *dk_ruleset; 86100206Sdd struct devfs_rule dk_rule; 87100206Sdd}; 88100206Sdd 89100206Sdd/* 90100206Sdd * Structure to describe a ruleset. 91100206Sdd */ 92100206Sddstruct devfs_ruleset { 93100206Sdd SLIST_ENTRY(devfs_ruleset) ds_list; 94100206Sdd devfs_rsnum ds_number; 95100206Sdd SLIST_HEAD(, devfs_krule) ds_rules; 96100206Sdd int ds_refcount; 97100206Sdd int ds_flags; 98100206Sdd#define DS_IMMUTABLE 0x001 99100793Sdd int ds_running; 100100206Sdd}; 101100206Sdd 102100206Sddstatic devfs_rid devfs_rid_input(devfs_rid rid, struct devfs_mount *dm); 103100206Sdd 104100206Sddstatic void devfs_rule_applyde(struct devfs_krule *dk,struct devfs_dirent *de); 105100206Sddstatic void devfs_rule_applyde_recursive(struct devfs_krule *dk, 106100206Sdd struct devfs_dirent *de); 107100206Sddstatic void devfs_rule_applydm(struct devfs_krule *dk, struct devfs_mount *dm); 108100206Sddstatic int devfs_rule_autonumber(struct devfs_ruleset *ds, devfs_rnum *rnp); 109100206Sddstatic struct devfs_krule *devfs_rule_byid(devfs_rid rid); 110100206Sddstatic int devfs_rule_delete(struct devfs_krule **dkp); 111100206Sddstatic dev_t devfs_rule_getdev(struct devfs_dirent *de); 112100206Sddstatic int devfs_rule_input(struct devfs_rule *dr, struct devfs_mount *dm); 113100206Sddstatic int devfs_rule_insert(struct devfs_rule *dr); 114100206Sddstatic int devfs_rule_match(struct devfs_krule *dk, struct devfs_dirent *de); 115100206Sddstatic int devfs_rule_matchpath(struct devfs_krule *dk, 116100206Sdd struct devfs_dirent *de); 117100206Sddstatic void devfs_rule_run(struct devfs_krule *dk, struct devfs_dirent *de); 118100206Sdd 119100206Sddstatic void devfs_ruleset_applyde(struct devfs_ruleset *ds, 120100206Sdd struct devfs_dirent *de); 121100206Sddstatic void devfs_ruleset_applydm(struct devfs_ruleset *ds, 122100206Sdd struct devfs_mount *dm); 123100206Sddstatic struct devfs_ruleset *devfs_ruleset_bynum(devfs_rsnum rsnum); 124100206Sddstatic struct devfs_ruleset *devfs_ruleset_create(devfs_rsnum rsnum); 125100206Sddstatic void devfs_ruleset_destroy(struct devfs_ruleset **dsp); 126100206Sddstatic void devfs_ruleset_reap(struct devfs_ruleset **dsp); 127100206Sddstatic int devfs_ruleset_use(devfs_rsnum rsnum, struct devfs_mount *dm); 128100206Sdd 129100206Sddstatic SLIST_HEAD(, devfs_ruleset) devfs_rulesets; 130100206Sdd 131100206Sdd/* 132100206Sdd * Called to apply the proper rules for de before the latter can be 133100206Sdd * exposed to the userland. This should be called with an exclusive 134100206Sdd * lock on dm in case we need to run anything. 135100206Sdd */ 136100206Sddvoid 137100206Sdddevfs_rules_apply(struct devfs_mount *dm, struct devfs_dirent *de) 138100206Sdd{ 139100206Sdd struct devfs_ruleset *ds; 140100206Sdd 141100206Sdd ds = devfs_ruleset_bynum(dm->dm_ruleset); 142100206Sdd KASSERT(ds != NULL, ("mount-point has NULL ruleset")); 143100206Sdd devfs_ruleset_applyde(ds, de); 144100206Sdd} 145100206Sdd 146100206Sdd/* 147100206Sdd * Rule subsystem SYSINIT hook. 148100206Sdd */ 149125855Sphkstatic void 150125855Sphkdevfs_rules_init(void *junk __unused) 151100206Sdd{ 152100206Sdd struct devfs_ruleset *ds; 153100206Sdd 154100206Sdd SLIST_INIT(&devfs_rulesets); 155100206Sdd 156100206Sdd ds = devfs_ruleset_create(0); 157100206Sdd ds->ds_flags |= DS_IMMUTABLE; 158100206Sdd ds->ds_refcount = 1; /* Prevent reaping. */ 159100206Sdd} 160100206Sdd 161125855SphkSYSINIT(devfs_rules, SI_SUB_DEVFS, SI_ORDER_FIRST, devfs_rules_init, NULL); 162125855Sphk 163100206Sdd/* 164100206Sdd * Rule subsystem ioctl hook. 165100206Sdd */ 166100206Sddint 167105212Sphkdevfs_rules_ioctl(struct mount *mp, u_long cmd, caddr_t data, struct thread *td) 168100206Sdd{ 169100206Sdd struct devfs_mount *dm = VFSTODEVFS(mp); 170100206Sdd struct devfs_ruleset *ds; 171100206Sdd struct devfs_krule *dk; 172100206Sdd struct devfs_rule *dr; 173100206Sdd devfs_rsnum rsnum; 174100206Sdd devfs_rnum rnum; 175100206Sdd devfs_rid rid; 176100206Sdd int error; 177100206Sdd 178100206Sdd /* 179100206Sdd * XXX: This returns an error regardless of whether we 180100206Sdd * actually support the cmd or not. 181100206Sdd */ 182100206Sdd error = suser(td); 183100206Sdd if (error != 0) 184100206Sdd return (error); 185100206Sdd 186100206Sdd lockmgr(&dm->dm_lock, LK_SHARED, 0, td); 187100206Sdd 188100206Sdd switch (cmd) { 189100206Sdd case DEVFSIO_RADD: 190100206Sdd dr = (struct devfs_rule *)data; 191100206Sdd error = devfs_rule_input(dr, dm); 192100206Sdd if (error != 0) 193100206Sdd goto out; 194100206Sdd dk = devfs_rule_byid(dr->dr_id); 195100206Sdd if (dk != NULL) { 196100206Sdd error = EEXIST; 197100206Sdd goto out; 198100206Sdd } 199100206Sdd lockmgr(&dm->dm_lock, LK_UPGRADE, 0, td); 200100206Sdd error = devfs_rule_insert(dr); 201100206Sdd break; 202100206Sdd case DEVFSIO_RAPPLY: 203100206Sdd dr = (struct devfs_rule *)data; 204100206Sdd error = devfs_rule_input(dr, dm); 205100206Sdd if (error != 0) 206100206Sdd goto out; 207100206Sdd 208100206Sdd /* 209100206Sdd * This is one of many possible hackish 210100206Sdd * implementations. The primary contender is an 211100206Sdd * implementation where the rule we read in is 212100206Sdd * temporarily inserted into some ruleset, perhaps 213100206Sdd * with a hypothetical DRO_NOAUTO flag so that it 214100206Sdd * doesn't get used where it isn't intended, and 215100206Sdd * applied in the normal way. This can be done in the 216100206Sdd * userland (DEVFSIO_ADD, DEVFSIO_APPLYID, 217100206Sdd * DEVFSIO_DEL) or in the kernel; either way it breaks 218100206Sdd * some corner case assumptions in other parts of the 219100206Sdd * code (not that this implementation doesn't do 220100206Sdd * that). 221100206Sdd */ 222100206Sdd if (dr->dr_iacts & DRA_INCSET && 223100206Sdd devfs_ruleset_bynum(dr->dr_incset) == NULL) { 224100206Sdd error = ESRCH; 225100206Sdd goto out; 226100206Sdd } 227111119Simp dk = malloc(sizeof(*dk), M_TEMP, M_WAITOK | M_ZERO); 228100206Sdd memcpy(&dk->dk_rule, dr, sizeof(*dr)); 229100206Sdd lockmgr(&dm->dm_lock, LK_UPGRADE, 0, td); 230100206Sdd devfs_rule_applydm(dk, dm); 231100206Sdd lockmgr(&dm->dm_lock, LK_DOWNGRADE, 0, td); 232100206Sdd free(dk, M_TEMP); 233100206Sdd error = 0; 234100206Sdd break; 235100206Sdd case DEVFSIO_RAPPLYID: 236100206Sdd rid = *(devfs_rid *)data; 237100206Sdd rid = devfs_rid_input(rid, dm); 238100206Sdd dk = devfs_rule_byid(rid); 239100206Sdd if (dk == NULL) { 240100206Sdd error = ENOENT; 241100206Sdd goto out; 242100206Sdd } 243100206Sdd lockmgr(&dm->dm_lock, LK_UPGRADE, 0, td); 244100206Sdd devfs_rule_applydm(dk, dm); 245100206Sdd error = 0; 246100206Sdd break; 247100206Sdd case DEVFSIO_RDEL: 248100206Sdd rid = *(devfs_rid *)data; 249100206Sdd rid = devfs_rid_input(rid, dm); 250100206Sdd dk = devfs_rule_byid(rid); 251100206Sdd if (dk == NULL) { 252100206Sdd error = ENOENT; 253100206Sdd goto out; 254100206Sdd } 255100206Sdd ds = dk->dk_ruleset; 256100206Sdd lockmgr(&dm->dm_lock, LK_UPGRADE, 0, td); 257100206Sdd error = devfs_rule_delete(&dk); 258100206Sdd devfs_ruleset_reap(&ds); 259100206Sdd break; 260100206Sdd case DEVFSIO_RGETNEXT: 261100206Sdd dr = (struct devfs_rule *)data; 262100206Sdd error = devfs_rule_input(dr, dm); 263100206Sdd if (error != 0) 264100206Sdd goto out; 265100206Sdd /* 266100206Sdd * We can't use devfs_rule_byid() here since that 267100206Sdd * requires the rule specified to exist, but we want 268100206Sdd * getnext(N) to work whether there is a rule N or not 269100206Sdd * (specifically, getnext(0) must work, but we should 270100206Sdd * never have a rule 0 since the add command 271100206Sdd * interprets 0 to mean "auto-number"). 272100206Sdd */ 273100206Sdd ds = devfs_ruleset_bynum(rid2rsn(dr->dr_id)); 274100206Sdd if (ds == NULL) { 275100206Sdd error = ENOENT; 276100206Sdd goto out; 277100206Sdd } 278100206Sdd rnum = rid2rn(dr->dr_id); 279100206Sdd SLIST_FOREACH(dk, &ds->ds_rules, dk_list) { 280100206Sdd if (rid2rn(dk->dk_rule.dr_id) > rnum) 281100206Sdd break; 282100206Sdd } 283100206Sdd if (dk == NULL) { 284100206Sdd error = ENOENT; 285100206Sdd goto out; 286100206Sdd } 287100206Sdd memcpy(dr, &dk->dk_rule, sizeof(*dr)); 288100206Sdd error = 0; 289100206Sdd break; 290100206Sdd case DEVFSIO_SUSE: 291100206Sdd rsnum = *(devfs_rsnum *)data; 292100206Sdd lockmgr(&dm->dm_lock, LK_UPGRADE, 0, td); 293100206Sdd error = devfs_ruleset_use(rsnum, dm); 294100206Sdd break; 295100206Sdd case DEVFSIO_SAPPLY: 296100206Sdd rsnum = *(devfs_rsnum *)data; 297100206Sdd rsnum = rid2rsn(devfs_rid_input(mkrid(rsnum, 0), dm)); 298100206Sdd ds = devfs_ruleset_bynum(rsnum); 299100206Sdd if (ds == NULL) { 300100206Sdd error = ESRCH; 301100206Sdd goto out; 302100206Sdd } 303100206Sdd lockmgr(&dm->dm_lock, LK_UPGRADE, 0, td); 304100206Sdd devfs_ruleset_applydm(ds, dm); 305100206Sdd error = 0; 306100206Sdd break; 307100206Sdd case DEVFSIO_SGETNEXT: 308100206Sdd rsnum = *(devfs_rsnum *)data; 309100206Sdd SLIST_FOREACH(ds, &devfs_rulesets, ds_list) { 310100206Sdd if (ds->ds_number > rsnum) 311100206Sdd break; 312100206Sdd } 313100206Sdd if (ds == NULL) 314100206Sdd error = ENOENT; 315100206Sdd else { 316100206Sdd *(devfs_rsnum *)data = ds->ds_number; 317100206Sdd error = 0; 318100206Sdd } 319100206Sdd break; 320100206Sdd default: 321100206Sdd error = ENOIOCTL; 322100206Sdd break; 323100206Sdd } 324100206Sdd 325100206Sddout: 326100206Sdd lockmgr(&dm->dm_lock, LK_RELEASE, 0, td); 327100206Sdd return (error); 328100206Sdd} 329100206Sdd 330100206Sdd/* 331100206Sdd * Called to initialize dm_ruleset when there is a new mount-point. 332100206Sdd */ 333100206Sddvoid 334100206Sdddevfs_rules_newmount(struct devfs_mount *dm, struct thread *td) 335100206Sdd{ 336100206Sdd struct devfs_ruleset *ds; 337100206Sdd 338100206Sdd lockmgr(&dm->dm_lock, LK_EXCLUSIVE, 0, td); 339100206Sdd /* 340100206Sdd * We can't use devfs_ruleset_use() since it will try to 341100206Sdd * decrement the refcount for the old ruleset, and there is no 342100206Sdd * old ruleset. Making some value of ds_ruleset "special" to 343100206Sdd * mean "don't decrement refcount" is uglier than this. 344100206Sdd */ 345100206Sdd ds = devfs_ruleset_bynum(0); 346100206Sdd KASSERT(ds != NULL, ("no ruleset 0")); 347100206Sdd ++ds->ds_refcount; 348100206Sdd dm->dm_ruleset = 0; 349100206Sdd lockmgr(&dm->dm_lock, LK_RELEASE, 0, td); 350100206Sdd} 351100206Sdd 352100206Sdd/* 353100206Sdd * Adjust the rule identifier to use the ruleset of dm if one isn't 354100206Sdd * explicitly specified. 355100206Sdd * 356100206Sdd * Note that after this operation, rid2rsn(rid) might still be 0, and 357100206Sdd * that's okay; ruleset 0 is a valid ruleset, but when it's read in 358100206Sdd * from the userland, it means "current ruleset for this mount-point". 359100206Sdd */ 360100206Sddstatic devfs_rid 361100206Sdddevfs_rid_input(devfs_rid rid, struct devfs_mount *dm) 362100206Sdd{ 363100206Sdd 364100206Sdd if (rid2rsn(rid) == 0) 365100206Sdd return (mkrid(dm->dm_ruleset, rid2rn(rid))); 366100206Sdd else 367100206Sdd return (rid); 368100206Sdd} 369100206Sdd 370100206Sdd/* 371100206Sdd * Apply dk to de. 372100206Sdd */ 373100206Sddstatic void 374100206Sdddevfs_rule_applyde(struct devfs_krule *dk, struct devfs_dirent *de) 375100206Sdd{ 376100206Sdd 377100206Sdd if (devfs_rule_match(dk, de)) 378100206Sdd devfs_rule_run(dk, de); 379100206Sdd} 380100206Sdd 381100206Sdd/* 382100206Sdd * Apply dk to de and everything under de. 383100206Sdd * 384100206Sdd * XXX: This method needs a function call for every nested 385100206Sdd * subdirectory in a devfs mount. If we plan to have many of these, 386100206Sdd * we might eventually run out of kernel stack space. 387100206Sdd */ 388100206Sddstatic void 389100206Sdddevfs_rule_applyde_recursive(struct devfs_krule *dk, struct devfs_dirent *de) 390100206Sdd{ 391100206Sdd struct devfs_dirent *de2; 392100206Sdd 393100206Sdd /* XXX: Should we apply to ourselves first or last? Does it matter? */ 394100206Sdd TAILQ_FOREACH(de2, &de->de_dlist, de_list) { 395100206Sdd devfs_rule_applyde_recursive(dk, de2); 396100206Sdd } 397100206Sdd devfs_rule_applyde(dk, de); 398100206Sdd} 399100206Sdd 400100206Sdd/* 401100206Sdd * Apply dk to all entires in dm. 402100206Sdd */ 403100206Sddstatic void 404100206Sdddevfs_rule_applydm(struct devfs_krule *dk, struct devfs_mount *dm) 405100206Sdd{ 406100206Sdd 407100206Sdd devfs_rule_applyde_recursive(dk, dm->dm_basedir); 408100206Sdd} 409100206Sdd 410100206Sdd/* 411100206Sdd * Automatically select a number for a new rule in ds, and write the 412100206Sdd * result into rnump. 413100206Sdd */ 414100206Sddstatic int 415100206Sdddevfs_rule_autonumber(struct devfs_ruleset *ds, devfs_rnum *rnump) 416100206Sdd{ 417100206Sdd struct devfs_krule *dk; 418100206Sdd 419100206Sdd /* Find the last rule. */ 420100206Sdd SLIST_FOREACH(dk, &ds->ds_rules, dk_list) { 421100206Sdd if (SLIST_NEXT(dk, dk_list) == NULL) 422100206Sdd break; 423100206Sdd } 424100206Sdd if (dk == NULL) 425100206Sdd *rnump = 100; 426100206Sdd else { 427100206Sdd *rnump = rid2rn(dk->dk_rule.dr_id) + 100; 428100206Sdd /* Detect overflow. */ 429100206Sdd if (*rnump < rid2rn(dk->dk_rule.dr_id)) 430100206Sdd return (ERANGE); 431100206Sdd } 432100206Sdd KASSERT(devfs_rule_byid(mkrid(ds->ds_number, *rnump)) == NULL, 433100206Sdd ("autonumbering resulted in an already existing rule")); 434100206Sdd return (0); 435100206Sdd} 436100206Sdd 437100206Sdd/* 438100206Sdd * Find a krule by id. 439100206Sdd */ 440100206Sddstatic struct devfs_krule * 441100206Sdddevfs_rule_byid(devfs_rid rid) 442100206Sdd{ 443100206Sdd struct devfs_ruleset *ds; 444100206Sdd struct devfs_krule *dk; 445100206Sdd devfs_rnum rn; 446100206Sdd 447100206Sdd rn = rid2rn(rid); 448100206Sdd ds = devfs_ruleset_bynum(rid2rsn(rid)); 449100206Sdd if (ds == NULL) 450100206Sdd return (NULL); 451100206Sdd SLIST_FOREACH(dk, &ds->ds_rules, dk_list) { 452100206Sdd if (rid2rn(dk->dk_rule.dr_id) == rn) 453100206Sdd return (dk); 454100206Sdd else if (rid2rn(dk->dk_rule.dr_id) > rn) 455100206Sdd break; 456100206Sdd } 457100206Sdd return (NULL); 458100206Sdd} 459100206Sdd 460100206Sdd/* 461100206Sdd * Remove dkp from any lists it may be on and remove memory associated 462100206Sdd * with it. 463100206Sdd */ 464100206Sddstatic int 465100206Sdddevfs_rule_delete(struct devfs_krule **dkp) 466100206Sdd{ 467100206Sdd struct devfs_krule *dk = *dkp; 468100206Sdd struct devfs_ruleset *ds; 469100206Sdd 470100206Sdd if (dk->dk_rule.dr_iacts & DRA_INCSET) { 471100206Sdd ds = devfs_ruleset_bynum(dk->dk_rule.dr_incset); 472100206Sdd KASSERT(ds != NULL, ("DRA_INCSET but bad dr_incset")); 473100206Sdd --ds->ds_refcount; 474100206Sdd devfs_ruleset_reap(&ds); 475100206Sdd } 476100206Sdd SLIST_REMOVE(&dk->dk_ruleset->ds_rules, dk, devfs_krule, dk_list); 477100206Sdd free(dk, M_DEVFS); 478100206Sdd *dkp = NULL; 479100206Sdd return (0); 480100206Sdd} 481100206Sdd 482100206Sdd/* 483100206Sdd * Get a dev_t corresponding to de so we can try to match rules based 484100206Sdd * on it. If this routine returns NULL, there is no dev_t associated 485100206Sdd * with the dirent (symlinks and directories don't have dev_ts), and 486100206Sdd * the caller should assume that any critera dependent on a dev_t 487100206Sdd * don't match. 488100206Sdd */ 489100206Sddstatic dev_t 490100206Sdddevfs_rule_getdev(struct devfs_dirent *de) 491100206Sdd{ 492100206Sdd dev_t *devp, dev; 493100206Sdd 494100206Sdd devp = devfs_itod(de->de_inode); 495100206Sdd if (devp != NULL) 496100206Sdd dev = *devp; 497100206Sdd else 498100206Sdd dev = NULL; 499100206Sdd /* If we think this dirent should have a dev_t, alert the user. */ 500100206Sdd if (dev == NULL && de->de_dirent->d_type != DT_LNK && 501100206Sdd de->de_dirent->d_type != DT_DIR) 502100206Sdd printf("Warning: no dev_t for %s\n", de->de_dirent->d_name); 503100206Sdd return (dev); 504100206Sdd} 505100206Sdd 506100206Sdd/* 507100206Sdd * Do what we need to do to a rule that we just loaded from the 508100206Sdd * userland. In particular, we need to check the magic, and adjust 509100206Sdd * the ruleset appropriate if desired. 510100206Sdd */ 511100206Sddstatic int 512100206Sdddevfs_rule_input(struct devfs_rule *dr, struct devfs_mount *dm) 513100206Sdd{ 514100206Sdd 515100206Sdd if (dr->dr_magic != DEVFS_MAGIC) 516100206Sdd return (ERPCMISMATCH); 517100206Sdd dr->dr_id = devfs_rid_input(dr->dr_id, dm); 518100206Sdd return (0); 519100206Sdd} 520100206Sdd 521100206Sdd/* 522100206Sdd * Import dr into the appropriate place in the kernel (i.e., make a 523100206Sdd * krule). The value of dr is copied, so the pointer may be destroyed 524100206Sdd * after this call completes. 525100206Sdd */ 526100206Sddstatic int 527100206Sdddevfs_rule_insert(struct devfs_rule *dr) 528100206Sdd{ 529100206Sdd struct devfs_ruleset *ds, *dsi; 530100206Sdd struct devfs_krule *k1, *k2; 531100206Sdd struct devfs_krule *dk; 532100206Sdd devfs_rsnum rsnum; 533100206Sdd devfs_rnum dkrn; 534100206Sdd int error; 535100206Sdd 536100206Sdd /* 537100206Sdd * This stuff seems out of place here, but we want to do it as 538100206Sdd * soon as possible so that if it fails, we don't have to roll 539100206Sdd * back any changes we already made (e.g., ruleset creation). 540100206Sdd */ 541100206Sdd if (dr->dr_iacts & DRA_INCSET) { 542100206Sdd dsi = devfs_ruleset_bynum(dr->dr_incset); 543100206Sdd if (dsi == NULL) 544100206Sdd return (ESRCH); 545100206Sdd } else 546100206Sdd dsi = NULL; 547100206Sdd 548100206Sdd rsnum = rid2rsn(dr->dr_id); 549100206Sdd ds = devfs_ruleset_bynum(rsnum); 550100206Sdd if (ds == NULL) 551100206Sdd ds = devfs_ruleset_create(rsnum); 552100206Sdd if (ds->ds_flags & DS_IMMUTABLE) 553100206Sdd return (EIO); 554100206Sdd dkrn = rid2rn(dr->dr_id); 555100206Sdd if (dkrn == 0) { 556100206Sdd error = devfs_rule_autonumber(ds, &dkrn); 557100206Sdd if (error != 0) 558100206Sdd return (error); 559100206Sdd } 560100206Sdd 561111119Simp dk = malloc(sizeof(*dk), M_DEVFS, M_WAITOK); 562100206Sdd dk->dk_ruleset = ds; 563100206Sdd if (dsi != NULL) 564100206Sdd ++dsi->ds_refcount; 565100206Sdd /* XXX: Inspect dr? */ 566100206Sdd memcpy(&dk->dk_rule, dr, sizeof(*dr)); 567100206Sdd dk->dk_rule.dr_id = mkrid(rid2rsn(dk->dk_rule.dr_id), dkrn); 568100206Sdd 569100206Sdd k1 = SLIST_FIRST(&ds->ds_rules); 570100206Sdd if (k1 == NULL || rid2rn(k1->dk_rule.dr_id) > dkrn) 571100206Sdd SLIST_INSERT_HEAD(&ds->ds_rules, dk, dk_list); 572100206Sdd else { 573100206Sdd SLIST_FOREACH(k1, &ds->ds_rules, dk_list) { 574100206Sdd k2 = SLIST_NEXT(k1, dk_list); 575100206Sdd if (k2 == NULL || rid2rn(k2->dk_rule.dr_id) > dkrn) { 576100206Sdd SLIST_INSERT_AFTER(k1, dk, dk_list); 577100206Sdd break; 578100206Sdd } 579100206Sdd } 580100206Sdd } 581100206Sdd 582100206Sdd return (0); 583100206Sdd} 584100206Sdd 585100206Sdd/* 586100206Sdd * Determine whether dk matches de. Returns 1 if dk should be run on 587100206Sdd * de; 0, otherwise. 588100206Sdd */ 589100206Sddstatic int 590100206Sdddevfs_rule_match(struct devfs_krule *dk, struct devfs_dirent *de) 591100206Sdd{ 592100206Sdd struct devfs_rule *dr = &dk->dk_rule; 593100206Sdd dev_t dev; 594100206Sdd 595100206Sdd dev = devfs_rule_getdev(de); 596100206Sdd /* 597100206Sdd * At this point, if dev is NULL, we should assume that any 598100206Sdd * criteria that depend on it don't match. We should *not* 599100206Sdd * just ignore them (i.e., act like they weren't specified), 600100206Sdd * since that makes a rule that only has criteria dependent on 601100206Sdd * the dev_t match all symlinks and directories. 602100206Sdd * 603100206Sdd * Note also that the following tests are somewhat reversed: 604100206Sdd * They're actually testing to see whether the condition does 605100206Sdd * *not* match, since the default is to assume the rule should 606100206Sdd * be run (such as if there are no conditions). 607100206Sdd */ 608100206Sdd if (dr->dr_icond & DRC_DSWFLAGS) 609100206Sdd if (dev == NULL || 610100206Sdd (dev->si_devsw->d_flags & dr->dr_dswflags) == 0) 611100206Sdd goto nomatch; 612100206Sdd if (dr->dr_icond & DRC_PATHPTRN) 613100206Sdd if (!devfs_rule_matchpath(dk, de)) 614100206Sdd goto nomatch; 615100206Sdd if (dr->dr_icond & DRC_MAJOR) 616100206Sdd if (dev == NULL || major(dev) != dr->dr_major) 617100206Sdd goto nomatch; 618100206Sdd 619100206Sdd return (1); 620100206Sdd 621100206Sddnomatch: 622100206Sdd return (0); 623100206Sdd} 624100206Sdd 625100206Sdd/* 626100206Sdd * Determine whether dk matches de on account of dr_pathptrn. 627100206Sdd */ 628100206Sddstatic int 629100206Sdddevfs_rule_matchpath(struct devfs_krule *dk, struct devfs_dirent *de) 630100206Sdd{ 631100206Sdd struct devfs_rule *dr = &dk->dk_rule; 632100206Sdd char *pname; 633100206Sdd dev_t dev; 634100206Sdd 635100206Sdd dev = devfs_rule_getdev(de); 636100206Sdd if (dev != NULL) 637100206Sdd pname = dev->si_name; 638124798Scperciva else if (de->de_dirent->d_type == DT_LNK || 639124804Scperciva de->de_dirent->d_type == DT_DIR) 640109090Sdd pname = de->de_dirent->d_name; 641100206Sdd else 642100206Sdd return (0); 643100206Sdd KASSERT(pname != NULL, ("devfs_rule_matchpath: NULL pname")); 644100206Sdd 645104653Sdd return (fnmatch(dr->dr_pathptrn, pname, 0) == 0); 646100206Sdd} 647100206Sdd 648100206Sdd/* 649100206Sdd * Run dk on de. 650100206Sdd */ 651100206Sddstatic void 652100206Sdddevfs_rule_run(struct devfs_krule *dk, struct devfs_dirent *de) 653100206Sdd{ 654100206Sdd struct devfs_rule *dr = &dk->dk_rule; 655100206Sdd struct devfs_ruleset *ds; 656100206Sdd 657100206Sdd if (dr->dr_iacts & DRA_BACTS) { 658100206Sdd if (dr->dr_bacts & DRB_HIDE) 659100206Sdd de->de_flags |= DE_WHITEOUT; 660100206Sdd if (dr->dr_bacts & DRB_UNHIDE) 661100206Sdd de->de_flags &= ~DE_WHITEOUT; 662100206Sdd } 663100206Sdd if (dr->dr_iacts & DRA_UID) 664100206Sdd de->de_uid = dr->dr_uid; 665100206Sdd if (dr->dr_iacts & DRA_GID) 666100206Sdd de->de_gid = dr->dr_gid; 667100206Sdd if (dr->dr_iacts & DRA_MODE) 668100206Sdd de->de_mode = dr->dr_mode; 669100206Sdd if (dr->dr_iacts & DRA_INCSET) { 670100206Sdd ds = devfs_ruleset_bynum(dk->dk_rule.dr_incset); 671100206Sdd KASSERT(ds != NULL, ("DRA_INCSET but bad dr_incset")); 672100793Sdd if (ds->ds_running) 673100793Sdd printf("Warning: avoiding loop through ruleset %d\n", 674100793Sdd ds->ds_number); 675100793Sdd else 676100206Sdd devfs_ruleset_applyde(ds, de); 677100206Sdd } 678100206Sdd} 679100206Sdd 680100206Sdd/* 681100206Sdd * Apply all the rules in ds to de. 682100206Sdd */ 683100206Sddstatic void 684100206Sdddevfs_ruleset_applyde(struct devfs_ruleset *ds, struct devfs_dirent *de) 685100206Sdd{ 686100206Sdd struct devfs_krule *dk; 687100206Sdd 688100793Sdd KASSERT(!ds->ds_running,("ruleset %d already running", ds->ds_number)); 689100793Sdd ds->ds_running = 1; 690100206Sdd SLIST_FOREACH(dk, &ds->ds_rules, dk_list) { 691100206Sdd devfs_rule_applyde(dk, de); 692100206Sdd } 693100793Sdd ds->ds_running = 0; 694100206Sdd} 695100206Sdd 696100206Sdd/* 697100206Sdd * Apply all the rules in ds to all the entires in dm. 698100206Sdd */ 699100206Sddstatic void 700100206Sdddevfs_ruleset_applydm(struct devfs_ruleset *ds, struct devfs_mount *dm) 701100206Sdd{ 702100206Sdd struct devfs_krule *dk; 703100206Sdd 704100793Sdd KASSERT(!ds->ds_running,("ruleset %d already running", ds->ds_number)); 705100793Sdd ds->ds_running = 1; 706100206Sdd /* 707100206Sdd * XXX: Does it matter whether we do 708100206Sdd * 709100206Sdd * foreach(dk in ds) 710100206Sdd * foreach(de in dm) 711100206Sdd * apply(dk to de) 712100206Sdd * 713100206Sdd * as opposed to 714100206Sdd * 715100206Sdd * foreach(de in dm) 716100206Sdd * foreach(dk in ds) 717100206Sdd * apply(dk to de) 718100206Sdd * 719100206Sdd * The end result is obviously the same, but does the order 720100206Sdd * matter? 721100206Sdd */ 722100206Sdd SLIST_FOREACH(dk, &ds->ds_rules, dk_list) { 723100206Sdd devfs_rule_applydm(dk, dm); 724100206Sdd } 725100793Sdd ds->ds_running = 0; 726100206Sdd} 727100206Sdd 728100206Sdd/* 729100206Sdd * Find a ruleset by number. 730100206Sdd */ 731100206Sddstatic struct devfs_ruleset * 732100206Sdddevfs_ruleset_bynum(devfs_rsnum rsnum) 733100206Sdd{ 734100206Sdd struct devfs_ruleset *ds; 735100206Sdd 736100206Sdd SLIST_FOREACH(ds, &devfs_rulesets, ds_list) { 737100206Sdd if (ds->ds_number == rsnum) 738100206Sdd return (ds); 739100206Sdd } 740100206Sdd return (NULL); 741100206Sdd} 742100206Sdd 743100206Sdd/* 744100206Sdd * Create a new ruleset. 745100206Sdd */ 746100206Sddstatic struct devfs_ruleset * 747100206Sdddevfs_ruleset_create(devfs_rsnum rsnum) 748100206Sdd{ 749100206Sdd struct devfs_ruleset *s1, *s2; 750100206Sdd struct devfs_ruleset *ds; 751100206Sdd 752100206Sdd KASSERT(devfs_ruleset_bynum(rsnum) == NULL, 753100206Sdd ("creating already existent ruleset %d", rsnum)); 754100206Sdd 755111119Simp ds = malloc(sizeof(*ds), M_DEVFS, M_WAITOK | M_ZERO); 756100206Sdd ds->ds_number = rsnum; 757100206Sdd ds->ds_refcount = ds->ds_flags = 0; 758100206Sdd SLIST_INIT(&ds->ds_rules); 759100206Sdd 760100206Sdd s1 = SLIST_FIRST(&devfs_rulesets); 761100206Sdd if (s1 == NULL || s1->ds_number > rsnum) 762100206Sdd SLIST_INSERT_HEAD(&devfs_rulesets, ds, ds_list); 763100206Sdd else { 764100206Sdd SLIST_FOREACH(s1, &devfs_rulesets, ds_list) { 765100206Sdd s2 = SLIST_NEXT(s1, ds_list); 766100206Sdd if (s2 == NULL || s2->ds_number > rsnum) { 767100206Sdd SLIST_INSERT_AFTER(s1, ds, ds_list); 768100206Sdd break; 769100206Sdd } 770100206Sdd } 771100206Sdd } 772100206Sdd 773100206Sdd return (ds); 774100206Sdd} 775100206Sdd 776100206Sdd/* 777100206Sdd * Remove a ruleset form the system. The ruleset specified must be 778100206Sdd * empty and not in use. 779100206Sdd */ 780100206Sddstatic void 781100206Sdddevfs_ruleset_destroy(struct devfs_ruleset **dsp) 782100206Sdd{ 783100206Sdd struct devfs_ruleset *ds = *dsp; 784100206Sdd 785100206Sdd KASSERT(SLIST_EMPTY(&ds->ds_rules), ("destroying non-empty ruleset")); 786100206Sdd KASSERT(ds->ds_refcount == 0, ("destroying busy ruleset")); 787100206Sdd KASSERT((ds->ds_flags & DS_IMMUTABLE) == 0, 788100206Sdd ("destroying immutable ruleset")); 789100206Sdd 790100206Sdd SLIST_REMOVE(&devfs_rulesets, ds, devfs_ruleset, ds_list); 791100206Sdd free(ds, M_DEVFS); 792100206Sdd *dsp = NULL; 793100206Sdd} 794100206Sdd 795100206Sdd/* 796100206Sdd * Remove a ruleset from the system if it's empty and not used 797100206Sdd * anywhere. This should be called after every time a rule is deleted 798100206Sdd * from this ruleset or the reference count is decremented. 799100206Sdd */ 800100206Sddstatic void 801100206Sdddevfs_ruleset_reap(struct devfs_ruleset **dsp) 802100206Sdd{ 803100206Sdd struct devfs_ruleset *ds = *dsp; 804100206Sdd 805100206Sdd if (SLIST_EMPTY(&ds->ds_rules) && ds->ds_refcount == 0) { 806100206Sdd devfs_ruleset_destroy(&ds); 807100206Sdd *dsp = ds; 808100206Sdd } 809100206Sdd} 810100206Sdd 811100206Sdd/* 812100206Sdd * Make rsnum the active ruleset for dm. 813100206Sdd */ 814100206Sddstatic int 815100206Sdddevfs_ruleset_use(devfs_rsnum rsnum, struct devfs_mount *dm) 816100206Sdd{ 817100206Sdd struct devfs_ruleset *cds, *ds; 818100206Sdd 819100206Sdd ds = devfs_ruleset_bynum(rsnum); 820100206Sdd if (ds == NULL) 821100206Sdd ds = devfs_ruleset_create(rsnum); 822100206Sdd cds = devfs_ruleset_bynum(dm->dm_ruleset); 823100206Sdd KASSERT(cds != NULL, ("mount-point has NULL ruleset")); 824100206Sdd 825100206Sdd /* These should probably be made atomic somehow. */ 826100206Sdd --cds->ds_refcount; 827100206Sdd ++ds->ds_refcount; 828100206Sdd dm->dm_ruleset = rsnum; 829100206Sdd 830100206Sdd devfs_ruleset_reap(&cds); 831100206Sdd return (0); 832100206Sdd} 833100206Sdd 834