devfs_rule.c revision 216391
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 216391 2010-12-12 08:52:13Z jh $ 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 <sys/param.h> 66100206Sdd#include <sys/systm.h> 67100206Sdd#include <sys/conf.h> 68100206Sdd#include <sys/kernel.h> 69100206Sdd#include <sys/malloc.h> 70164033Srwatson#include <sys/priv.h> 71100206Sdd#include <sys/dirent.h> 72100206Sdd#include <sys/ioccom.h> 73150342Sphk#include <sys/lock.h> 74150150Sphk#include <sys/sx.h> 75100206Sdd 76100206Sdd#include <fs/devfs/devfs.h> 77150342Sphk#include <fs/devfs/devfs_int.h> 78100206Sdd 79100206Sdd/* 80100206Sdd * Kernel version of devfs_rule. 81100206Sdd */ 82100206Sddstruct devfs_krule { 83150501Sphk TAILQ_ENTRY(devfs_krule) dk_list; 84150501Sphk struct devfs_ruleset *dk_ruleset; 85150501Sphk struct devfs_rule dk_rule; 86100206Sdd}; 87100206Sdd 88150501SphkTAILQ_HEAD(rulehead, devfs_krule); 89150501Sphkstatic MALLOC_DEFINE(M_DEVFSRULE, "DEVFS_RULE", "DEVFS rule storage"); 90150501Sphk 91100206Sdd/* 92100206Sdd * Structure to describe a ruleset. 93100206Sdd */ 94100206Sddstruct devfs_ruleset { 95150501Sphk TAILQ_ENTRY(devfs_ruleset) ds_list; 96150501Sphk struct rulehead ds_rules; 97150501Sphk devfs_rsnum ds_number; 98150501Sphk int ds_refcount; 99100206Sdd}; 100100206Sdd 101100206Sddstatic devfs_rid devfs_rid_input(devfs_rid rid, struct devfs_mount *dm); 102100206Sdd 103100206Sddstatic void devfs_rule_applyde_recursive(struct devfs_krule *dk, 104100206Sdd struct devfs_dirent *de); 105100206Sddstatic void devfs_rule_applydm(struct devfs_krule *dk, struct devfs_mount *dm); 106100206Sddstatic int devfs_rule_autonumber(struct devfs_ruleset *ds, devfs_rnum *rnp); 107100206Sddstatic struct devfs_krule *devfs_rule_byid(devfs_rid rid); 108150501Sphkstatic int devfs_rule_delete(struct devfs_krule *dkp); 109130585Sphkstatic struct cdev *devfs_rule_getdev(struct devfs_dirent *de); 110100206Sddstatic int devfs_rule_input(struct devfs_rule *dr, struct devfs_mount *dm); 111100206Sddstatic int devfs_rule_insert(struct devfs_rule *dr); 112100206Sddstatic int devfs_rule_match(struct devfs_krule *dk, struct devfs_dirent *de); 113100206Sddstatic int devfs_rule_matchpath(struct devfs_krule *dk, 114100206Sdd struct devfs_dirent *de); 115150147Sphkstatic void devfs_rule_run(struct devfs_krule *dk, struct devfs_dirent *de, unsigned depth); 116100206Sdd 117100206Sddstatic void devfs_ruleset_applyde(struct devfs_ruleset *ds, 118150147Sphk struct devfs_dirent *de, unsigned depth); 119100206Sddstatic void devfs_ruleset_applydm(struct devfs_ruleset *ds, 120100206Sdd struct devfs_mount *dm); 121100206Sddstatic struct devfs_ruleset *devfs_ruleset_bynum(devfs_rsnum rsnum); 122100206Sddstatic struct devfs_ruleset *devfs_ruleset_create(devfs_rsnum rsnum); 123150501Sphkstatic void devfs_ruleset_reap(struct devfs_ruleset *dsp); 124100206Sddstatic int devfs_ruleset_use(devfs_rsnum rsnum, struct devfs_mount *dm); 125100206Sdd 126150150Sphkstatic struct sx sx_rules; 127150501SphkSX_SYSINIT(sx_rules, &sx_rules, "DEVFS ruleset lock"); 128100206Sdd 129150501Sphkstatic TAILQ_HEAD(, devfs_ruleset) devfs_rulesets = 130150501Sphk TAILQ_HEAD_INITIALIZER(devfs_rulesets); 131150501Sphk 132100206Sdd/* 133150147Sphk * Called to apply the proper rules for 'de' before it can be 134100206Sdd * exposed to the userland. This should be called with an exclusive 135100206Sdd * lock on dm in case we need to run anything. 136100206Sdd */ 137100206Sddvoid 138100206Sdddevfs_rules_apply(struct devfs_mount *dm, struct devfs_dirent *de) 139100206Sdd{ 140100206Sdd struct devfs_ruleset *ds; 141100206Sdd 142150501Sphk if (dm->dm_ruleset == 0) 143150501Sphk return; 144150150Sphk sx_slock(&sx_rules); 145100206Sdd ds = devfs_ruleset_bynum(dm->dm_ruleset); 146100206Sdd KASSERT(ds != NULL, ("mount-point has NULL ruleset")); 147150147Sphk devfs_ruleset_applyde(ds, de, devfs_rule_depth); 148150150Sphk sx_sunlock(&sx_rules); 149100206Sdd} 150100206Sdd 151100206Sdd/* 152100206Sdd * Rule subsystem ioctl hook. 153100206Sdd */ 154100206Sddint 155150149Sphkdevfs_rules_ioctl(struct devfs_mount *dm, u_long cmd, caddr_t data, struct thread *td) 156100206Sdd{ 157100206Sdd struct devfs_ruleset *ds; 158100206Sdd struct devfs_krule *dk; 159100206Sdd struct devfs_rule *dr; 160100206Sdd devfs_rsnum rsnum; 161100206Sdd devfs_rnum rnum; 162100206Sdd devfs_rid rid; 163100206Sdd int error; 164100206Sdd 165150342Sphk sx_assert(&dm->dm_lock, SX_XLOCKED); 166150342Sphk 167100206Sdd /* 168164033Srwatson * XXX: This returns an error regardless of whether we actually 169164033Srwatson * support the cmd or not. 170164033Srwatson * 171164033Srwatson * We could make this privileges finer grained if desired. 172100206Sdd */ 173164033Srwatson error = priv_check(td, PRIV_DEVFS_RULE); 174164033Srwatson if (error) 175100206Sdd return (error); 176100206Sdd 177150150Sphk sx_xlock(&sx_rules); 178150342Sphk 179100206Sdd switch (cmd) { 180100206Sdd case DEVFSIO_RADD: 181100206Sdd dr = (struct devfs_rule *)data; 182100206Sdd error = devfs_rule_input(dr, dm); 183100206Sdd if (error != 0) 184150501Sphk break; 185100206Sdd dk = devfs_rule_byid(dr->dr_id); 186100206Sdd if (dk != NULL) { 187100206Sdd error = EEXIST; 188150501Sphk break; 189100206Sdd } 190153986Srwatson if (rid2rsn(dr->dr_id) == 0) { 191153986Srwatson error = EIO; 192153986Srwatson break; 193153986Srwatson } 194100206Sdd error = devfs_rule_insert(dr); 195100206Sdd break; 196100206Sdd case DEVFSIO_RAPPLY: 197100206Sdd dr = (struct devfs_rule *)data; 198100206Sdd error = devfs_rule_input(dr, dm); 199100206Sdd if (error != 0) 200150501Sphk break; 201100206Sdd 202100206Sdd /* 203100206Sdd * This is one of many possible hackish 204100206Sdd * implementations. The primary contender is an 205100206Sdd * implementation where the rule we read in is 206100206Sdd * temporarily inserted into some ruleset, perhaps 207100206Sdd * with a hypothetical DRO_NOAUTO flag so that it 208100206Sdd * doesn't get used where it isn't intended, and 209100206Sdd * applied in the normal way. This can be done in the 210100206Sdd * userland (DEVFSIO_ADD, DEVFSIO_APPLYID, 211100206Sdd * DEVFSIO_DEL) or in the kernel; either way it breaks 212100206Sdd * some corner case assumptions in other parts of the 213100206Sdd * code (not that this implementation doesn't do 214100206Sdd * that). 215100206Sdd */ 216100206Sdd if (dr->dr_iacts & DRA_INCSET && 217100206Sdd devfs_ruleset_bynum(dr->dr_incset) == NULL) { 218100206Sdd error = ESRCH; 219150501Sphk break; 220100206Sdd } 221111119Simp dk = malloc(sizeof(*dk), M_TEMP, M_WAITOK | M_ZERO); 222100206Sdd memcpy(&dk->dk_rule, dr, sizeof(*dr)); 223100206Sdd devfs_rule_applydm(dk, dm); 224100206Sdd free(dk, M_TEMP); 225100206Sdd break; 226100206Sdd case DEVFSIO_RAPPLYID: 227100206Sdd rid = *(devfs_rid *)data; 228100206Sdd rid = devfs_rid_input(rid, dm); 229100206Sdd dk = devfs_rule_byid(rid); 230100206Sdd if (dk == NULL) { 231100206Sdd error = ENOENT; 232150501Sphk break; 233100206Sdd } 234100206Sdd devfs_rule_applydm(dk, dm); 235100206Sdd break; 236100206Sdd case DEVFSIO_RDEL: 237100206Sdd rid = *(devfs_rid *)data; 238100206Sdd rid = devfs_rid_input(rid, dm); 239100206Sdd dk = devfs_rule_byid(rid); 240100206Sdd if (dk == NULL) { 241100206Sdd error = ENOENT; 242150501Sphk break; 243100206Sdd } 244100206Sdd ds = dk->dk_ruleset; 245150501Sphk error = devfs_rule_delete(dk); 246100206Sdd break; 247100206Sdd case DEVFSIO_RGETNEXT: 248100206Sdd dr = (struct devfs_rule *)data; 249100206Sdd error = devfs_rule_input(dr, dm); 250100206Sdd if (error != 0) 251150501Sphk break; 252100206Sdd /* 253100206Sdd * We can't use devfs_rule_byid() here since that 254100206Sdd * requires the rule specified to exist, but we want 255100206Sdd * getnext(N) to work whether there is a rule N or not 256100206Sdd * (specifically, getnext(0) must work, but we should 257100206Sdd * never have a rule 0 since the add command 258100206Sdd * interprets 0 to mean "auto-number"). 259100206Sdd */ 260100206Sdd ds = devfs_ruleset_bynum(rid2rsn(dr->dr_id)); 261100206Sdd if (ds == NULL) { 262100206Sdd error = ENOENT; 263150501Sphk break; 264100206Sdd } 265100206Sdd rnum = rid2rn(dr->dr_id); 266150501Sphk TAILQ_FOREACH(dk, &ds->ds_rules, dk_list) { 267100206Sdd if (rid2rn(dk->dk_rule.dr_id) > rnum) 268100206Sdd break; 269100206Sdd } 270100206Sdd if (dk == NULL) { 271100206Sdd error = ENOENT; 272150501Sphk break; 273100206Sdd } 274100206Sdd memcpy(dr, &dk->dk_rule, sizeof(*dr)); 275100206Sdd break; 276100206Sdd case DEVFSIO_SUSE: 277100206Sdd rsnum = *(devfs_rsnum *)data; 278100206Sdd error = devfs_ruleset_use(rsnum, dm); 279100206Sdd break; 280100206Sdd case DEVFSIO_SAPPLY: 281100206Sdd rsnum = *(devfs_rsnum *)data; 282100206Sdd rsnum = rid2rsn(devfs_rid_input(mkrid(rsnum, 0), dm)); 283100206Sdd ds = devfs_ruleset_bynum(rsnum); 284100206Sdd if (ds == NULL) { 285100206Sdd error = ESRCH; 286150501Sphk break; 287100206Sdd } 288100206Sdd devfs_ruleset_applydm(ds, dm); 289100206Sdd break; 290100206Sdd case DEVFSIO_SGETNEXT: 291100206Sdd rsnum = *(devfs_rsnum *)data; 292150501Sphk TAILQ_FOREACH(ds, &devfs_rulesets, ds_list) { 293100206Sdd if (ds->ds_number > rsnum) 294100206Sdd break; 295100206Sdd } 296150501Sphk if (ds == NULL) { 297100206Sdd error = ENOENT; 298150501Sphk break; 299100206Sdd } 300150501Sphk *(devfs_rsnum *)data = ds->ds_number; 301100206Sdd break; 302100206Sdd default: 303100206Sdd error = ENOIOCTL; 304100206Sdd break; 305100206Sdd } 306100206Sdd 307150150Sphk sx_xunlock(&sx_rules); 308100206Sdd return (error); 309100206Sdd} 310100206Sdd 311100206Sdd/* 312100206Sdd * Adjust the rule identifier to use the ruleset of dm if one isn't 313100206Sdd * explicitly specified. 314100206Sdd * 315100206Sdd * Note that after this operation, rid2rsn(rid) might still be 0, and 316100206Sdd * that's okay; ruleset 0 is a valid ruleset, but when it's read in 317100206Sdd * from the userland, it means "current ruleset for this mount-point". 318100206Sdd */ 319100206Sddstatic devfs_rid 320100206Sdddevfs_rid_input(devfs_rid rid, struct devfs_mount *dm) 321100206Sdd{ 322100206Sdd 323100206Sdd if (rid2rsn(rid) == 0) 324100206Sdd return (mkrid(dm->dm_ruleset, rid2rn(rid))); 325100206Sdd else 326100206Sdd return (rid); 327100206Sdd} 328100206Sdd 329100206Sdd/* 330100206Sdd * Apply dk to de and everything under de. 331100206Sdd * 332100206Sdd * XXX: This method needs a function call for every nested 333100206Sdd * subdirectory in a devfs mount. If we plan to have many of these, 334100206Sdd * we might eventually run out of kernel stack space. 335150342Sphk * XXX: a linear search could be done through the cdev list instead. 336100206Sdd */ 337100206Sddstatic void 338100206Sdddevfs_rule_applyde_recursive(struct devfs_krule *dk, struct devfs_dirent *de) 339100206Sdd{ 340100206Sdd struct devfs_dirent *de2; 341100206Sdd 342150147Sphk TAILQ_FOREACH(de2, &de->de_dlist, de_list) 343100206Sdd devfs_rule_applyde_recursive(dk, de2); 344150147Sphk devfs_rule_run(dk, de, devfs_rule_depth); 345100206Sdd} 346100206Sdd 347100206Sdd/* 348100206Sdd * Apply dk to all entires in dm. 349100206Sdd */ 350100206Sddstatic void 351100206Sdddevfs_rule_applydm(struct devfs_krule *dk, struct devfs_mount *dm) 352100206Sdd{ 353100206Sdd 354149107Sphk devfs_rule_applyde_recursive(dk, dm->dm_rootdir); 355100206Sdd} 356100206Sdd 357100206Sdd/* 358100206Sdd * Automatically select a number for a new rule in ds, and write the 359100206Sdd * result into rnump. 360100206Sdd */ 361100206Sddstatic int 362100206Sdddevfs_rule_autonumber(struct devfs_ruleset *ds, devfs_rnum *rnump) 363100206Sdd{ 364100206Sdd struct devfs_krule *dk; 365100206Sdd 366100206Sdd /* Find the last rule. */ 367150501Sphk dk = TAILQ_LAST(&ds->ds_rules, rulehead); 368100206Sdd if (dk == NULL) 369100206Sdd *rnump = 100; 370100206Sdd else { 371100206Sdd *rnump = rid2rn(dk->dk_rule.dr_id) + 100; 372100206Sdd /* Detect overflow. */ 373100206Sdd if (*rnump < rid2rn(dk->dk_rule.dr_id)) 374100206Sdd return (ERANGE); 375100206Sdd } 376100206Sdd KASSERT(devfs_rule_byid(mkrid(ds->ds_number, *rnump)) == NULL, 377100206Sdd ("autonumbering resulted in an already existing rule")); 378100206Sdd return (0); 379100206Sdd} 380100206Sdd 381100206Sdd/* 382100206Sdd * Find a krule by id. 383100206Sdd */ 384100206Sddstatic struct devfs_krule * 385100206Sdddevfs_rule_byid(devfs_rid rid) 386100206Sdd{ 387100206Sdd struct devfs_ruleset *ds; 388100206Sdd struct devfs_krule *dk; 389100206Sdd devfs_rnum rn; 390100206Sdd 391100206Sdd rn = rid2rn(rid); 392100206Sdd ds = devfs_ruleset_bynum(rid2rsn(rid)); 393100206Sdd if (ds == NULL) 394100206Sdd return (NULL); 395150501Sphk TAILQ_FOREACH(dk, &ds->ds_rules, dk_list) { 396100206Sdd if (rid2rn(dk->dk_rule.dr_id) == rn) 397100206Sdd return (dk); 398100206Sdd else if (rid2rn(dk->dk_rule.dr_id) > rn) 399100206Sdd break; 400100206Sdd } 401100206Sdd return (NULL); 402100206Sdd} 403100206Sdd 404100206Sdd/* 405100206Sdd * Remove dkp from any lists it may be on and remove memory associated 406100206Sdd * with it. 407100206Sdd */ 408100206Sddstatic int 409150501Sphkdevfs_rule_delete(struct devfs_krule *dk) 410100206Sdd{ 411100206Sdd struct devfs_ruleset *ds; 412100206Sdd 413100206Sdd if (dk->dk_rule.dr_iacts & DRA_INCSET) { 414100206Sdd ds = devfs_ruleset_bynum(dk->dk_rule.dr_incset); 415100206Sdd KASSERT(ds != NULL, ("DRA_INCSET but bad dr_incset")); 416100206Sdd --ds->ds_refcount; 417150501Sphk devfs_ruleset_reap(ds); 418100206Sdd } 419150501Sphk ds = dk->dk_ruleset; 420150501Sphk TAILQ_REMOVE(&ds->ds_rules, dk, dk_list); 421150501Sphk devfs_ruleset_reap(ds); 422150501Sphk free(dk, M_DEVFSRULE); 423100206Sdd return (0); 424100206Sdd} 425100206Sdd 426100206Sdd/* 427130585Sphk * Get a struct cdev *corresponding to de so we can try to match rules based 428130585Sphk * on it. If this routine returns NULL, there is no struct cdev *associated 429100206Sdd * with the dirent (symlinks and directories don't have dev_ts), and 430100206Sdd * the caller should assume that any critera dependent on a dev_t 431100206Sdd * don't match. 432100206Sdd */ 433130585Sphkstatic struct cdev * 434100206Sdddevfs_rule_getdev(struct devfs_dirent *de) 435100206Sdd{ 436100206Sdd 437150342Sphk if (de->de_cdp == NULL) 438150342Sphk return (NULL); 439150342Sphk if (de->de_cdp->cdp_flags & CDP_ACTIVE) 440150342Sphk return (&de->de_cdp->cdp_c); 441100206Sdd else 442150342Sphk return (NULL); 443100206Sdd} 444100206Sdd 445100206Sdd/* 446100206Sdd * Do what we need to do to a rule that we just loaded from the 447100206Sdd * userland. In particular, we need to check the magic, and adjust 448100206Sdd * the ruleset appropriate if desired. 449100206Sdd */ 450100206Sddstatic int 451100206Sdddevfs_rule_input(struct devfs_rule *dr, struct devfs_mount *dm) 452100206Sdd{ 453100206Sdd 454100206Sdd if (dr->dr_magic != DEVFS_MAGIC) 455100206Sdd return (ERPCMISMATCH); 456100206Sdd dr->dr_id = devfs_rid_input(dr->dr_id, dm); 457100206Sdd return (0); 458100206Sdd} 459100206Sdd 460100206Sdd/* 461100206Sdd * Import dr into the appropriate place in the kernel (i.e., make a 462100206Sdd * krule). The value of dr is copied, so the pointer may be destroyed 463100206Sdd * after this call completes. 464100206Sdd */ 465100206Sddstatic int 466100206Sdddevfs_rule_insert(struct devfs_rule *dr) 467100206Sdd{ 468100206Sdd struct devfs_ruleset *ds, *dsi; 469150501Sphk struct devfs_krule *k1; 470100206Sdd struct devfs_krule *dk; 471100206Sdd devfs_rsnum rsnum; 472100206Sdd devfs_rnum dkrn; 473100206Sdd int error; 474100206Sdd 475100206Sdd /* 476100206Sdd * This stuff seems out of place here, but we want to do it as 477100206Sdd * soon as possible so that if it fails, we don't have to roll 478100206Sdd * back any changes we already made (e.g., ruleset creation). 479100206Sdd */ 480100206Sdd if (dr->dr_iacts & DRA_INCSET) { 481100206Sdd dsi = devfs_ruleset_bynum(dr->dr_incset); 482100206Sdd if (dsi == NULL) 483100206Sdd return (ESRCH); 484100206Sdd } else 485100206Sdd dsi = NULL; 486100206Sdd 487100206Sdd rsnum = rid2rsn(dr->dr_id); 488150501Sphk KASSERT(rsnum != 0, ("Inserting into ruleset zero")); 489150501Sphk 490100206Sdd ds = devfs_ruleset_bynum(rsnum); 491100206Sdd if (ds == NULL) 492100206Sdd ds = devfs_ruleset_create(rsnum); 493100206Sdd dkrn = rid2rn(dr->dr_id); 494100206Sdd if (dkrn == 0) { 495100206Sdd error = devfs_rule_autonumber(ds, &dkrn); 496150501Sphk if (error != 0) { 497150501Sphk devfs_ruleset_reap(ds); 498100206Sdd return (error); 499150501Sphk } 500100206Sdd } 501100206Sdd 502150501Sphk dk = malloc(sizeof(*dk), M_DEVFSRULE, M_WAITOK | M_ZERO); 503100206Sdd dk->dk_ruleset = ds; 504100206Sdd if (dsi != NULL) 505100206Sdd ++dsi->ds_refcount; 506100206Sdd /* XXX: Inspect dr? */ 507100206Sdd memcpy(&dk->dk_rule, dr, sizeof(*dr)); 508100206Sdd dk->dk_rule.dr_id = mkrid(rid2rsn(dk->dk_rule.dr_id), dkrn); 509100206Sdd 510150501Sphk TAILQ_FOREACH(k1, &ds->ds_rules, dk_list) { 511150501Sphk if (rid2rn(k1->dk_rule.dr_id) > dkrn) { 512150501Sphk TAILQ_INSERT_BEFORE(k1, dk, dk_list); 513150501Sphk break; 514100206Sdd } 515100206Sdd } 516150501Sphk if (k1 == NULL) 517150501Sphk TAILQ_INSERT_TAIL(&ds->ds_rules, dk, dk_list); 518100206Sdd return (0); 519100206Sdd} 520100206Sdd 521100206Sdd/* 522100206Sdd * Determine whether dk matches de. Returns 1 if dk should be run on 523100206Sdd * de; 0, otherwise. 524100206Sdd */ 525100206Sddstatic int 526100206Sdddevfs_rule_match(struct devfs_krule *dk, struct devfs_dirent *de) 527100206Sdd{ 528100206Sdd struct devfs_rule *dr = &dk->dk_rule; 529130585Sphk struct cdev *dev; 530177458Skib struct cdevsw *dsw; 531210923Skib int ref; 532100206Sdd 533100206Sdd dev = devfs_rule_getdev(de); 534100206Sdd /* 535100206Sdd * At this point, if dev is NULL, we should assume that any 536100206Sdd * criteria that depend on it don't match. We should *not* 537100206Sdd * just ignore them (i.e., act like they weren't specified), 538100206Sdd * since that makes a rule that only has criteria dependent on 539130585Sphk * the struct cdev *match all symlinks and directories. 540100206Sdd * 541100206Sdd * Note also that the following tests are somewhat reversed: 542100206Sdd * They're actually testing to see whether the condition does 543100206Sdd * *not* match, since the default is to assume the rule should 544100206Sdd * be run (such as if there are no conditions). 545100206Sdd */ 546177458Skib if (dr->dr_icond & DRC_DSWFLAGS) { 547177458Skib if (dev == NULL) 548150147Sphk return (0); 549210923Skib dsw = dev_refthread(dev, &ref); 550177458Skib if (dsw == NULL) 551177458Skib return (0); 552177458Skib if ((dsw->d_flags & dr->dr_dswflags) == 0) { 553210923Skib dev_relthread(dev, ref); 554177458Skib return (0); 555177458Skib } 556210923Skib dev_relthread(dev, ref); 557177458Skib } 558100206Sdd if (dr->dr_icond & DRC_PATHPTRN) 559100206Sdd if (!devfs_rule_matchpath(dk, de)) 560150147Sphk return (0); 561100206Sdd 562100206Sdd return (1); 563100206Sdd} 564100206Sdd 565100206Sdd/* 566100206Sdd * Determine whether dk matches de on account of dr_pathptrn. 567100206Sdd */ 568100206Sddstatic int 569100206Sdddevfs_rule_matchpath(struct devfs_krule *dk, struct devfs_dirent *de) 570100206Sdd{ 571100206Sdd struct devfs_rule *dr = &dk->dk_rule; 572100206Sdd char *pname; 573130585Sphk struct cdev *dev; 574100206Sdd 575100206Sdd dev = devfs_rule_getdev(de); 576100206Sdd if (dev != NULL) 577100206Sdd pname = dev->si_name; 578124798Scperciva else if (de->de_dirent->d_type == DT_LNK || 579124804Scperciva de->de_dirent->d_type == DT_DIR) 580109090Sdd pname = de->de_dirent->d_name; 581100206Sdd else 582100206Sdd return (0); 583100206Sdd KASSERT(pname != NULL, ("devfs_rule_matchpath: NULL pname")); 584100206Sdd 585104653Sdd return (fnmatch(dr->dr_pathptrn, pname, 0) == 0); 586100206Sdd} 587100206Sdd 588100206Sdd/* 589100206Sdd * Run dk on de. 590100206Sdd */ 591100206Sddstatic void 592150147Sphkdevfs_rule_run(struct devfs_krule *dk, struct devfs_dirent *de, unsigned depth) 593100206Sdd{ 594100206Sdd struct devfs_rule *dr = &dk->dk_rule; 595100206Sdd struct devfs_ruleset *ds; 596100206Sdd 597150147Sphk if (!devfs_rule_match(dk, de)) 598150147Sphk return; 599100206Sdd if (dr->dr_iacts & DRA_BACTS) { 600100206Sdd if (dr->dr_bacts & DRB_HIDE) 601100206Sdd de->de_flags |= DE_WHITEOUT; 602100206Sdd if (dr->dr_bacts & DRB_UNHIDE) 603100206Sdd de->de_flags &= ~DE_WHITEOUT; 604100206Sdd } 605100206Sdd if (dr->dr_iacts & DRA_UID) 606100206Sdd de->de_uid = dr->dr_uid; 607100206Sdd if (dr->dr_iacts & DRA_GID) 608100206Sdd de->de_gid = dr->dr_gid; 609100206Sdd if (dr->dr_iacts & DRA_MODE) 610100206Sdd de->de_mode = dr->dr_mode; 611100206Sdd if (dr->dr_iacts & DRA_INCSET) { 612150147Sphk /* 613150147Sphk * XXX: we should tell the user if the depth is exceeded here 614150147Sphk * XXX: but it is not obvious how to. A return value will 615150147Sphk * XXX: not work as this is called when devices are created 616150147Sphk * XXX: long time after the rules were instantiated. 617150147Sphk * XXX: a printf() would probably give too much noise, or 618150147Sphk * XXX: DoS the machine. I guess a a rate-limited message 619150147Sphk * XXX: might work. 620150147Sphk */ 621150147Sphk if (depth > 0) { 622150147Sphk ds = devfs_ruleset_bynum(dk->dk_rule.dr_incset); 623150147Sphk KASSERT(ds != NULL, ("DRA_INCSET but bad dr_incset")); 624150147Sphk devfs_ruleset_applyde(ds, de, depth - 1); 625150147Sphk } 626100206Sdd } 627100206Sdd} 628100206Sdd 629100206Sdd/* 630100206Sdd * Apply all the rules in ds to de. 631100206Sdd */ 632100206Sddstatic void 633150147Sphkdevfs_ruleset_applyde(struct devfs_ruleset *ds, struct devfs_dirent *de, unsigned depth) 634100206Sdd{ 635100206Sdd struct devfs_krule *dk; 636100206Sdd 637150501Sphk TAILQ_FOREACH(dk, &ds->ds_rules, dk_list) 638150147Sphk devfs_rule_run(dk, de, depth); 639100206Sdd} 640100206Sdd 641100206Sdd/* 642100206Sdd * Apply all the rules in ds to all the entires in dm. 643100206Sdd */ 644100206Sddstatic void 645100206Sdddevfs_ruleset_applydm(struct devfs_ruleset *ds, struct devfs_mount *dm) 646100206Sdd{ 647100206Sdd struct devfs_krule *dk; 648100206Sdd 649100206Sdd /* 650100206Sdd * XXX: Does it matter whether we do 651100206Sdd * 652100206Sdd * foreach(dk in ds) 653100206Sdd * foreach(de in dm) 654100206Sdd * apply(dk to de) 655100206Sdd * 656100206Sdd * as opposed to 657100206Sdd * 658100206Sdd * foreach(de in dm) 659100206Sdd * foreach(dk in ds) 660100206Sdd * apply(dk to de) 661100206Sdd * 662100206Sdd * The end result is obviously the same, but does the order 663100206Sdd * matter? 664100206Sdd */ 665150501Sphk TAILQ_FOREACH(dk, &ds->ds_rules, dk_list) 666100206Sdd devfs_rule_applydm(dk, dm); 667100206Sdd} 668100206Sdd 669100206Sdd/* 670100206Sdd * Find a ruleset by number. 671100206Sdd */ 672100206Sddstatic struct devfs_ruleset * 673100206Sdddevfs_ruleset_bynum(devfs_rsnum rsnum) 674100206Sdd{ 675100206Sdd struct devfs_ruleset *ds; 676100206Sdd 677150501Sphk TAILQ_FOREACH(ds, &devfs_rulesets, ds_list) { 678100206Sdd if (ds->ds_number == rsnum) 679100206Sdd return (ds); 680100206Sdd } 681100206Sdd return (NULL); 682100206Sdd} 683100206Sdd 684100206Sdd/* 685100206Sdd * Create a new ruleset. 686100206Sdd */ 687100206Sddstatic struct devfs_ruleset * 688100206Sdddevfs_ruleset_create(devfs_rsnum rsnum) 689100206Sdd{ 690150501Sphk struct devfs_ruleset *s1; 691100206Sdd struct devfs_ruleset *ds; 692100206Sdd 693150501Sphk KASSERT(rsnum != 0, ("creating ruleset zero")); 694150501Sphk 695100206Sdd KASSERT(devfs_ruleset_bynum(rsnum) == NULL, 696100206Sdd ("creating already existent ruleset %d", rsnum)); 697100206Sdd 698150501Sphk ds = malloc(sizeof(*ds), M_DEVFSRULE, M_WAITOK | M_ZERO); 699100206Sdd ds->ds_number = rsnum; 700150501Sphk TAILQ_INIT(&ds->ds_rules); 701100206Sdd 702150501Sphk TAILQ_FOREACH(s1, &devfs_rulesets, ds_list) { 703150501Sphk if (s1->ds_number > rsnum) { 704150501Sphk TAILQ_INSERT_BEFORE(s1, ds, ds_list); 705150501Sphk break; 706100206Sdd } 707100206Sdd } 708150501Sphk if (s1 == NULL) 709150501Sphk TAILQ_INSERT_TAIL(&devfs_rulesets, ds, ds_list); 710100206Sdd return (ds); 711100206Sdd} 712100206Sdd 713100206Sdd/* 714100206Sdd * Remove a ruleset from the system if it's empty and not used 715100206Sdd * anywhere. This should be called after every time a rule is deleted 716100206Sdd * from this ruleset or the reference count is decremented. 717100206Sdd */ 718100206Sddstatic void 719150501Sphkdevfs_ruleset_reap(struct devfs_ruleset *ds) 720100206Sdd{ 721100206Sdd 722150501Sphk KASSERT(ds->ds_number != 0, ("reaping ruleset zero ")); 723150501Sphk 724150501Sphk if (!TAILQ_EMPTY(&ds->ds_rules) || ds->ds_refcount != 0) 725150501Sphk return; 726150501Sphk 727150501Sphk TAILQ_REMOVE(&devfs_rulesets, ds, ds_list); 728150501Sphk free(ds, M_DEVFSRULE); 729100206Sdd} 730100206Sdd 731100206Sdd/* 732100206Sdd * Make rsnum the active ruleset for dm. 733100206Sdd */ 734100206Sddstatic int 735100206Sdddevfs_ruleset_use(devfs_rsnum rsnum, struct devfs_mount *dm) 736100206Sdd{ 737100206Sdd struct devfs_ruleset *cds, *ds; 738100206Sdd 739150501Sphk if (dm->dm_ruleset != 0) { 740150501Sphk cds = devfs_ruleset_bynum(dm->dm_ruleset); 741150501Sphk --cds->ds_refcount; 742150501Sphk devfs_ruleset_reap(cds); 743150501Sphk } 744100206Sdd 745216391Sjh if (rsnum == 0) { 746216391Sjh dm->dm_ruleset = 0; 747216391Sjh return (0); 748216391Sjh } 749216391Sjh 750179926Sgonzo ds = devfs_ruleset_bynum(rsnum); 751179926Sgonzo if (ds == NULL) 752179926Sgonzo ds = devfs_ruleset_create(rsnum); 753100206Sdd /* These should probably be made atomic somehow. */ 754100206Sdd ++ds->ds_refcount; 755100206Sdd dm->dm_ruleset = rsnum; 756100206Sdd 757100206Sdd return (0); 758100206Sdd} 759150501Sphk 760150501Sphkvoid 761150501Sphkdevfs_rules_cleanup(struct devfs_mount *dm) 762150501Sphk{ 763150501Sphk struct devfs_ruleset *ds; 764150501Sphk 765150501Sphk sx_assert(&dm->dm_lock, SX_XLOCKED); 766150501Sphk if (dm->dm_ruleset != 0) { 767150501Sphk ds = devfs_ruleset_bynum(dm->dm_ruleset); 768150501Sphk --ds->ds_refcount; 769150501Sphk devfs_ruleset_reap(ds); 770150501Sphk } 771150501Sphk} 772