xref: /netbsd-src/usr.sbin/puffs/mount_sysctlfs/sysctlfs.c (revision 0fb3a34de4c38db9537dcd3083d650ceb0aea07b)
1 /*	$NetBSD: sysctlfs.c,v 1.21 2023/04/02 18:23:02 ryo Exp $	*/
2 
3 /*-
4  * Copyright (c) 2006, 2007  Antti Kantee.  All Rights Reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
16  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 /*
29  * sysctlfs: mount sysctls as a file system tree.  Supports query and
30  * modify of nodes in the sysctl namespace in addition to namespace
31  * traversal.
32  */
33 
34 #include <sys/cdefs.h>
35 #ifndef lint
36 __RCSID("$NetBSD: sysctlfs.c,v 1.21 2023/04/02 18:23:02 ryo Exp $");
37 #endif /* !lint */
38 
39 #include <sys/types.h>
40 #include <sys/sysctl.h>
41 
42 #include <stdio.h>
43 #include <assert.h>
44 #include <err.h>
45 #include <errno.h>
46 #include <mntopts.h>
47 #include <paths.h>
48 #include <puffs.h>
49 #include <stdlib.h>
50 #include <string.h>
51 #include <unistd.h>
52 #include <util.h>
53 
54 #ifdef RUMP_ACTION
55 #include <rump/rump.h>
56 #include <rump/rump_syscalls.h>
57 
58 #define sysctl(a,b,c,d,e,f) rump_sys___sysctl(a,b,c,d,e,f)
59 #endif
60 
61 PUFFSOP_PROTOS(sysctlfs)
62 
63 struct sfsnode {
64 	int sysctl_flags;
65 	ino_t myid;
66 };
67 
68 #define SFSPATH_DOTDOT 0
69 #define SFSPATH_NORMAL 1
70 
71 #define N_HIERARCHY 10
72 typedef int SfsName[N_HIERARCHY];
73 
74 struct sfsfid {
75 	int len;
76 	SfsName path;
77 };
78 
79 static struct sfsnode rn;
80 static SfsName sname_root;
81 static struct timespec fstime;
82 
83 static ino_t nextid = 3;
84 static mode_t fileperms;
85 static uid_t fileuid;
86 static gid_t filegid;
87 
88 static int rflag;
89 
90 #define ISADIR(a) ((SYSCTL_TYPE(a->sysctl_flags) == CTLTYPE_NODE))
91 #define SFS_MAXFILE 32768
92 #define SFS_NODEPERDIR 128
93 
94 static int sysctlfs_domount(struct puffs_usermount *);
95 
96 /*
97  * build paths.  doesn't support rename (but neither does the fs)
98  */
99 static int
sysctlfs_pathbuild(struct puffs_usermount * pu,const struct puffs_pathobj * parent,const struct puffs_pathobj * comp,size_t offset,struct puffs_pathobj * res)100 sysctlfs_pathbuild(struct puffs_usermount *pu,
101     const struct puffs_pathobj *parent, const struct puffs_pathobj *comp,
102     size_t offset, struct puffs_pathobj *res)
103 {
104 	SfsName *sname;
105 	size_t clen;
106 
107 	assert(parent->po_len < N_HIERARCHY); /* code uses +1 */
108 
109 	sname = malloc(sizeof(SfsName));
110 	assert(sname != NULL);
111 
112 	clen = parent->po_len;
113 	if (comp->po_len == SFSPATH_DOTDOT) {
114 		assert(clen != 0);
115 		clen--;
116 	}
117 
118 	memcpy(sname, parent->po_path, clen * sizeof(int));
119 
120 	res->po_path = sname;
121 	res->po_len = clen;
122 
123 	return 0;
124 }
125 
126 static int
sysctlfs_pathtransform(struct puffs_usermount * pu,const struct puffs_pathobj * p,const struct puffs_cn * pcn,struct puffs_pathobj * res)127 sysctlfs_pathtransform(struct puffs_usermount *pu,
128     const struct puffs_pathobj *p, const struct puffs_cn *pcn,
129     struct puffs_pathobj *res)
130 {
131 
132 	res->po_path = NULL;
133 	/*
134 	 * XXX: overload.  prevents us from doing rename, but the fs
135 	 * (and sysctl(3)) doesn't support it, so no biggie
136 	 */
137 	if (PCNISDOTDOT(pcn)) {
138 		res->po_len = SFSPATH_DOTDOT;
139 	}else {
140 		res->po_len = SFSPATH_NORMAL;
141 	}
142 
143 	return 0;
144 }
145 
146 static int
sysctlfs_pathcmp(struct puffs_usermount * pu,struct puffs_pathobj * po1,struct puffs_pathobj * po2,size_t clen,int checkprefix)147 sysctlfs_pathcmp(struct puffs_usermount *pu, struct puffs_pathobj *po1,
148     struct puffs_pathobj *po2, size_t clen, int checkprefix)
149 {
150 
151 	if (memcmp(po1->po_path, po2->po_path, clen * sizeof(int)) == 0)
152 		return 0;
153 	return 1;
154 }
155 
156 static void
sysctlfs_pathfree(struct puffs_usermount * pu,struct puffs_pathobj * po)157 sysctlfs_pathfree(struct puffs_usermount *pu, struct puffs_pathobj *po)
158 {
159 
160 	free(po->po_path);
161 }
162 
163 static struct puffs_node *
getnode(struct puffs_usermount * pu,struct puffs_pathobj * po,int nodetype)164 getnode(struct puffs_usermount *pu, struct puffs_pathobj *po, int nodetype)
165 {
166 	struct sysctlnode sn[SFS_NODEPERDIR];
167 	struct sysctlnode qnode;
168 	struct puffs_node *pn;
169 	struct sfsnode *sfs;
170 	SfsName myname, *sname;
171 	size_t sl, i;
172 
173 	/*
174 	 * Check if we need to create a new in-memory node or if we
175 	 * already have one for this path.  Shortcut for the rootnode.
176 	 * Also, memcmp against zero-length would be quite true always.
177 	 */
178 	if (po->po_len == 0)
179 		pn = puffs_getroot(pu);
180 	else
181 		pn = puffs_pn_nodewalk(pu, puffs_path_walkcmp, po);
182 
183 	if (pn != NULL)
184 		return pn;
185 	/*
186 	 * don't know nodetype?  query...
187 	 *
188 	 * XXX1: nothing really guarantees 0 is an invalid nodetype
189 	 * XXX2: is there really no easier way of doing this?  we
190 	 *       know the whole mib path
191 	 */
192 	if (!nodetype) {
193 		sname = po->po_path;
194 		memcpy(myname, po->po_path, po->po_len * sizeof(myname[0]));
195 
196 		memset(&qnode, 0, sizeof(qnode));
197 		qnode.sysctl_flags = SYSCTL_VERSION;
198 		myname[po->po_len-1] = CTL_QUERY;
199 
200 		sl = sizeof(sn);
201 		if (sysctl(myname, po->po_len, sn, &sl,
202 		    &qnode, sizeof(qnode)) == -1)
203 			abort();
204 
205 		for (i = 0; i < sl / sizeof(struct sysctlnode); i++) {
206 			 if (sn[i].sysctl_num == (*sname)[po->po_len-1]) {
207 				nodetype = sn[i].sysctl_flags;
208 				break;
209 			}
210 		}
211 		if (!nodetype)
212 			return NULL;
213 	}
214 
215 	sfs = emalloc(sizeof(*sfs));
216 	sfs->sysctl_flags = nodetype;
217 	sfs->myid = nextid++;
218 
219 	pn = puffs_pn_new(pu, sfs);
220 	assert(pn);
221 
222 	return pn;
223 }
224 
225 static void __dead
usage(void)226 usage(void)
227 {
228 
229 	fprintf(stderr, "Usage: %s [-o <mntopts>] sysctlfs mountpath\n",
230 	    getprogname());
231 	exit(1);
232 }
233 
234 int
main(int argc,char * argv[])235 main(int argc, char *argv[])
236 {
237 	struct puffs_usermount *pu;
238 	struct puffs_ops *pops;
239 	mntoptparse_t mp;
240 	int mntflags, pflags;
241 	int detach;
242 	int ch;
243 
244 	setprogname(argv[0]);
245 
246 	if (argc < 2)
247 		usage();
248 
249 	mntflags = pflags = 0;
250 	detach = 1;
251 	while ((ch = getopt(argc, argv, "o:rs")) != -1) {
252 		switch (ch) {
253 		case 'o':
254 			mp = getmntopts(optarg, puffsmopts, &mntflags, &pflags);
255 			if (mp == NULL)
256 				err(EXIT_FAILURE, "getmntopts");
257 			freemntopts(mp);
258 			break;
259 		case 'r':
260 			rflag = 1;
261 			break;
262 		case 's':
263 			detach = 0;
264 			break;
265 		}
266 	}
267 	argv += optind;
268 	argc -= optind;
269 	pflags |= PUFFS_FLAG_BUILDPATH | PUFFS_KFLAG_NOCACHE;
270 
271 	if (pflags & PUFFS_FLAG_OPDUMP)
272 		detach = 0;
273 
274 	if (argc != 2)
275 		usage();
276 
277 	PUFFSOP_INIT(pops);
278 
279 	PUFFSOP_SETFSNOP(pops, unmount);
280 	PUFFSOP_SETFSNOP(pops, sync);
281 	PUFFSOP_SETFSNOP(pops, statvfs);
282 	PUFFSOP_SET(pops, sysctlfs, fs, nodetofh);
283 	PUFFSOP_SET(pops, sysctlfs, fs, fhtonode);
284 
285 	PUFFSOP_SET(pops, sysctlfs, node, lookup);
286 	PUFFSOP_SET(pops, sysctlfs, node, getattr);
287 	PUFFSOP_SET(pops, sysctlfs, node, setattr);
288 	PUFFSOP_SET(pops, sysctlfs, node, readdir);
289 	PUFFSOP_SET(pops, sysctlfs, node, read);
290 	PUFFSOP_SET(pops, sysctlfs, node, write);
291 	PUFFSOP_SET(pops, puffs_genfs, node, reclaim);
292 
293 	pu = puffs_init(pops, _PATH_PUFFS, "sysctlfs", NULL, pflags);
294 	if (pu == NULL)
295 		err(EXIT_FAILURE, "puffs_init");
296 
297 	puffs_set_pathbuild(pu, sysctlfs_pathbuild);
298 	puffs_set_pathtransform(pu, sysctlfs_pathtransform);
299 	puffs_set_pathcmp(pu, sysctlfs_pathcmp);
300 	puffs_set_pathfree(pu, sysctlfs_pathfree);
301 
302 	puffs_setfhsize(pu, sizeof(struct sfsfid), PUFFS_FHFLAG_NFSV3);
303 
304 	if (sysctlfs_domount(pu) != 0)
305 		errx(EXIT_FAILURE, "domount");
306 
307 	if (detach)
308 		if (puffs_daemon(pu, 1, 1) == -1)
309 			err(EXIT_FAILURE, "puffs_daemon");
310 
311 #ifdef RUMP_ACTION
312 	{
313 		extern int puffs_fakecc;
314 		puffs_fakecc = 1;
315 		rump_init();
316 	}
317 #endif
318 
319 	if (puffs_mount(pu, argv[1], mntflags, puffs_getroot(pu)) == -1)
320 		err(EXIT_FAILURE, "puffs_mount");
321 	if (puffs_mainloop(pu) == -1)
322 		err(EXIT_FAILURE, "mainloop");
323 
324 	return 0;
325 }
326 
327 static int
sysctlfs_domount(struct puffs_usermount * pu)328 sysctlfs_domount(struct puffs_usermount *pu)
329 {
330 	struct puffs_pathobj *po_root;
331 	struct puffs_node *pn_root;
332 	struct timeval tv_now;
333 
334 	rn.myid = 2;
335 	rn.sysctl_flags = CTLTYPE_NODE;
336 
337 	gettimeofday(&tv_now, NULL);
338 	TIMEVAL_TO_TIMESPEC(&tv_now, &fstime);
339 
340 	pn_root = puffs_pn_new(pu, &rn);
341 	assert(pn_root != NULL);
342 	puffs_setroot(pu, pn_root);
343 
344 	po_root = puffs_getrootpathobj(pu);
345 	po_root->po_path = &sname_root;
346 	po_root->po_len = 0;
347 
348 	fileuid = geteuid();
349 	filegid = getegid();
350 
351 	if (fileuid == 0)
352 		fileperms = 0644;
353 	else
354 		fileperms = 0444;
355 
356 	return 0;
357 }
358 
359 int
sysctlfs_fs_fhtonode(struct puffs_usermount * pu,void * fid,size_t fidsize,struct puffs_newinfo * pni)360 sysctlfs_fs_fhtonode(struct puffs_usermount *pu, void *fid, size_t fidsize,
361 	struct puffs_newinfo *pni)
362 {
363 	struct puffs_pathobj po;
364 	struct puffs_node *pn;
365 	struct sfsnode *sfs;
366 	struct sfsfid *sfid;
367 
368 	sfid = fid;
369 
370 	po.po_len = sfid->len;
371 	po.po_path = &sfid->path;
372 
373 	pn = getnode(pu, &po, 0);
374 	if (pn == NULL)
375 		return EINVAL;
376 	sfs = pn->pn_data;
377 
378 	puffs_newinfo_setcookie(pni, pn);
379 	if (ISADIR(sfs))
380 		puffs_newinfo_setvtype(pni, VDIR);
381 	else
382 		puffs_newinfo_setvtype(pni, VREG);
383 
384 	return 0;
385 }
386 
387 int
sysctlfs_fs_nodetofh(struct puffs_usermount * pu,void * cookie,void * fid,size_t * fidsize)388 sysctlfs_fs_nodetofh(struct puffs_usermount *pu, void *cookie,
389 	void *fid, size_t *fidsize)
390 {
391 	struct puffs_node *pn = cookie;
392 	struct sfsfid *sfid;
393 
394 	sfid = fid;
395 	sfid->len = PNPLEN(pn);
396 	memcpy(&sfid->path, PNPATH(pn), sfid->len * sizeof(int));
397 
398 	return 0;
399 }
400 
401 static void
getnodedata(struct sfsnode * sfs,struct puffs_pathobj * po,char * buf,size_t * bufsize)402 getnodedata(struct sfsnode *sfs, struct puffs_pathobj *po,
403 	char *buf, size_t *bufsize)
404 {
405 	size_t sz;
406 	int error = 0;
407 
408 	assert(!ISADIR(sfs));
409 
410 	memset(buf, 0, *bufsize);
411 	switch (SYSCTL_TYPE(sfs->sysctl_flags)) {
412 	case CTLTYPE_BOOL: {
413 		bool b;
414 		sz = sizeof(bool);
415 		assert(sz <= *bufsize);
416 		if (sysctl(po->po_path, po->po_len, &b, &sz, NULL, 0) == -1) {
417 			error = errno;
418 			break;
419 		}
420 		if (rflag)
421 			memcpy(buf, &b, sz);
422 		else
423 			snprintf(buf, *bufsize, "%s", b ? "true" : "false");
424 		break;
425 	}
426 	case CTLTYPE_INT: {
427 		int i;
428 		sz = sizeof(int);
429 		assert(sz <= *bufsize);
430 		if (sysctl(po->po_path, po->po_len, &i, &sz, NULL, 0) == -1) {
431 			error = errno;
432 			break;
433 		}
434 		if (rflag)
435 			memcpy(buf, &i, sz);
436 		else
437 			snprintf(buf, *bufsize, "%d", i);
438 		break;
439 	}
440 	case CTLTYPE_QUAD: {
441 		quad_t q;
442 		sz = sizeof(q);
443 		assert(sz <= *bufsize);
444 		if (sysctl(po->po_path, po->po_len, &q, &sz, NULL, 0) == -1) {
445 			error = errno;
446 			break;
447 		}
448 		if (rflag)
449 			memcpy(buf, &q, sz);
450 		else
451 			snprintf(buf, *bufsize, "%" PRId64, q);
452 		break;
453 	}
454 	case CTLTYPE_STRUCT: {
455 		uint8_t snode[SFS_MAXFILE/2-1];
456 		unsigned i;
457 
458 		sz = sizeof(snode);
459 		assert(sz <= *bufsize);
460 		if (sysctl(po->po_path, po->po_len, snode, &sz, NULL, 0) == -1){
461 			error = errno;
462 			break;
463 		}
464 		if (rflag) {
465 			memcpy(buf, &snode, sz);
466 		} else {
467 			for (i = 0; i < sz && 2*i < *bufsize; i++) {
468 				sprintf(&buf[2*i], "%02x", snode[i]);
469 			}
470 			buf[2*i] = '\0';
471 		}
472 		break;
473 	}
474 	case CTLTYPE_STRING: {
475 		sz = *bufsize;
476 		assert(sz <= *bufsize);
477 		if (sysctl(po->po_path, po->po_len, buf, &sz, NULL, 0) == -1) {
478 			error = errno;
479 			break;
480 		}
481 		break;
482 	}
483 	default:
484 		snprintf(buf, *bufsize, "invalid sysctl CTLTYPE %d",
485 		    SYSCTL_TYPE(sfs->sysctl_flags));
486 		break;
487 	}
488 
489 	if (error) {
490 		*bufsize = 0;
491 		return;
492 	}
493 
494 	if (rflag)
495 		*bufsize = sz;
496 	else
497 		*bufsize = strlen(buf);
498 }
499 
500 static int
getlinks(struct sfsnode * sfs,struct puffs_pathobj * po)501 getlinks(struct sfsnode *sfs, struct puffs_pathobj *po)
502 {
503 	struct sysctlnode sn[SFS_NODEPERDIR];
504 	struct sysctlnode qnode;
505 	SfsName *sname;
506 	size_t sl;
507 
508 	if (!ISADIR(sfs))
509 		return 1;
510 
511 	memset(&qnode, 0, sizeof(qnode));
512 	sl = sizeof(sn);
513 	qnode.sysctl_flags = SYSCTL_VERSION;
514 	sname = po->po_path;
515 	(*sname)[po->po_len] = CTL_QUERY;
516 
517 	if (sysctl(*sname, po->po_len + 1, sn, &sl,
518 	    &qnode, sizeof(qnode)) == -1)
519 		return 0;
520 
521 	return (sl / sizeof(sn[0])) + 2;
522 }
523 
524 static int
getsize(struct sfsnode * sfs,struct puffs_pathobj * po)525 getsize(struct sfsnode *sfs, struct puffs_pathobj *po)
526 {
527 	char buf[SFS_MAXFILE];
528 	size_t sz = sizeof(buf);
529 
530 	if (ISADIR(sfs))
531 		return getlinks(sfs, po) * 16; /* totally arbitrary */
532 
533 	getnodedata(sfs, po, buf, &sz);
534 	if (rflag)
535 		return sz;
536 	else
537 		return sz + 1; /* for \n, not \0 */
538 }
539 
540 int
sysctlfs_node_lookup(struct puffs_usermount * pu,void * opc,struct puffs_newinfo * pni,const struct puffs_cn * pcn)541 sysctlfs_node_lookup(struct puffs_usermount *pu, void *opc,
542 	struct puffs_newinfo *pni, const struct puffs_cn *pcn)
543 {
544 	struct puffs_cn *p2cn = __UNCONST(pcn); /* XXX: fix the interface */
545 	struct sysctlnode sn[SFS_NODEPERDIR];
546 	struct sysctlnode qnode;
547 	struct puffs_node *pn_dir = opc;
548 	struct puffs_node *pn_new;
549 	struct sfsnode *sfs_dir = pn_dir->pn_data, *sfs_new;
550 	SfsName *sname = PCNPATH(pcn);
551 	size_t sl, i;
552 	int nodetype;
553 
554 	assert(ISADIR(sfs_dir));
555 
556 	/*
557 	 * If we're looking for dotdot, we already have the entire pathname
558 	 * in sname, courtesy of pathbuild, so we can skip this step.
559 	 */
560 	if (!PCNISDOTDOT(pcn)) {
561 		memset(&qnode, 0, sizeof(qnode));
562 		sl = SFS_NODEPERDIR * sizeof(struct sysctlnode);
563 		qnode.sysctl_flags = SYSCTL_VERSION;
564 		(*sname)[PCNPLEN(pcn)] = CTL_QUERY;
565 
566 		if (sysctl(*sname, PCNPLEN(pcn) + 1, sn, &sl,
567 		    &qnode, sizeof(qnode)) == -1)
568 			return ENOENT;
569 
570 		for (i = 0; i < sl / sizeof(struct sysctlnode); i++)
571 			if (strcmp(sn[i].sysctl_name, pcn->pcn_name) == 0)
572 				break;
573 		if (i == sl / sizeof(struct sysctlnode))
574 			return ENOENT;
575 
576 		(*sname)[PCNPLEN(pcn)] = sn[i].sysctl_num;
577 		p2cn->pcn_po_full.po_len++;
578 		nodetype = sn[i].sysctl_flags;
579 	} else
580 		nodetype = CTLTYPE_NODE;
581 
582 	pn_new = getnode(pu, &p2cn->pcn_po_full, nodetype);
583 	if (pn_new == NULL)
584 		return ENOENT;
585 	sfs_new = pn_new->pn_data;
586 
587 	puffs_newinfo_setcookie(pni, pn_new);
588 	if (ISADIR(sfs_new))
589 		puffs_newinfo_setvtype(pni, VDIR);
590 	else
591 		puffs_newinfo_setvtype(pni, VREG);
592 
593 	return 0;
594 }
595 
596 int
sysctlfs_node_getattr(struct puffs_usermount * pu,void * opc,struct vattr * va,const struct puffs_cred * pcr)597 sysctlfs_node_getattr(struct puffs_usermount *pu, void *opc, struct vattr *va,
598 	const struct puffs_cred *pcr)
599 {
600 	struct puffs_node *pn = opc;
601 	struct sfsnode *sfs = pn->pn_data;
602 
603 	memset(va, 0, sizeof(struct vattr));
604 
605 	if (ISADIR(sfs)) {
606 		va->va_type = VDIR;
607 		va->va_mode = 0555;
608 	} else {
609 		va->va_type = VREG;
610 		va->va_mode = fileperms;
611 	}
612 	va->va_uid = fileuid;
613 	va->va_gid = filegid;
614 	va->va_nlink = getlinks(sfs, &pn->pn_po);
615 	va->va_fileid = sfs->myid;
616 	va->va_size = getsize(sfs, &pn->pn_po);
617 	va->va_gen = 1;
618 	va->va_rdev = PUFFS_VNOVAL;
619 	va->va_blocksize = 512;
620 	va->va_filerev = 1;
621 
622 	va->va_atime = va->va_mtime = va->va_ctime = va->va_birthtime = fstime;
623 
624 	return 0;
625 }
626 
627 int
sysctlfs_node_setattr(struct puffs_usermount * pu,void * opc,const struct vattr * va,const struct puffs_cred * pcr)628 sysctlfs_node_setattr(struct puffs_usermount *pu, void *opc,
629 	const struct vattr *va, const struct puffs_cred *pcr)
630 {
631 
632 	/* dummy, but required for write */
633 	/* XXX: we could return EOPNOTSUPP or something */
634 	return 0;
635 }
636 
637 int
sysctlfs_node_readdir(struct puffs_usermount * pu,void * opc,struct dirent * dent,off_t * readoff,size_t * reslen,const struct puffs_cred * pcr,int * eofflag,off_t * cookies,size_t * ncookies)638 sysctlfs_node_readdir(struct puffs_usermount *pu, void *opc,
639 	struct dirent *dent, off_t *readoff, size_t *reslen,
640 	const struct puffs_cred *pcr, int *eofflag,
641 	off_t *cookies, size_t *ncookies)
642 {
643 	struct sysctlnode sn[SFS_NODEPERDIR];
644 	struct sysctlnode qnode;
645 	struct puffs_node *pn_dir = opc;
646 	struct puffs_node *pn_res;
647 	struct puffs_pathobj po;
648 	struct sfsnode *sfs_dir = pn_dir->pn_data, *sfs_ent;
649 	SfsName *sname;
650 	size_t sl, i;
651 	enum vtype vt;
652 	ino_t id;
653 
654 	*ncookies = 0;
655 
656  again:
657 	if (*readoff == DENT_DOT || *readoff == DENT_DOTDOT) {
658 		puffs_gendotdent(&dent, sfs_dir->myid, *readoff, reslen);
659 		(*readoff)++;
660 		PUFFS_STORE_DCOOKIE(cookies, ncookies, *readoff);
661 		goto again;
662 	}
663 
664 	memset(&qnode, 0, sizeof(qnode));
665 	sl = SFS_NODEPERDIR * sizeof(struct sysctlnode);
666 	qnode.sysctl_flags = SYSCTL_VERSION;
667 	sname = PNPATH(pn_dir);
668 	(*sname)[PNPLEN(pn_dir)] = CTL_QUERY;
669 
670 	if (sysctl(*sname, PNPLEN(pn_dir) + 1, sn, &sl,
671 	    &qnode, sizeof(qnode)) == -1)
672 		return ENOENT;
673 
674 	po.po_path = sname;
675 	po.po_len = PNPLEN(pn_dir)+1;
676 
677 	for (i = DENT_ADJ(*readoff); i < sl / sizeof(struct sysctlnode); i++) {
678 		if (SYSCTL_TYPE(sn[i].sysctl_flags) == CTLTYPE_NODE)
679 			vt = VDIR;
680 		else
681 			vt = VREG;
682 
683 		/*
684 		 * check if the node exists.  if so, give it the real
685 		 * inode number.  otherwise just fake it.
686 		 */
687 		(*sname)[PNPLEN(pn_dir)] = sn[i].sysctl_num;
688 		pn_res = puffs_pn_nodewalk(pu, puffs_path_walkcmp, &po);
689 		if (pn_res) {
690 			sfs_ent = pn_res->pn_data;
691 			id = sfs_ent->myid;
692 		} else {
693 			id = nextid++;
694 		}
695 
696 		if (!puffs_nextdent(&dent, sn[i].sysctl_name, id,
697 		    puffs_vtype2dt(vt), reslen))
698 			return 0;
699 
700 		(*readoff)++;
701 		PUFFS_STORE_DCOOKIE(cookies, ncookies, *readoff);
702 	}
703 
704 	*eofflag = 1;
705 	return 0;
706 }
707 
708 int
sysctlfs_node_read(struct puffs_usermount * pu,void * opc,uint8_t * buf,off_t offset,size_t * resid,const struct puffs_cred * pcr,int ioflag)709 sysctlfs_node_read(struct puffs_usermount *pu, void *opc, uint8_t *buf,
710 	off_t offset, size_t *resid, const struct puffs_cred *pcr,
711 	int ioflag)
712 {
713 	char localbuf[SFS_MAXFILE];
714 	struct puffs_node *pn = opc;
715 	struct sfsnode *sfs = pn->pn_data;
716 	size_t sz = sizeof(localbuf);
717 	int xfer;
718 
719 	if (ISADIR(sfs))
720 		return EISDIR;
721 
722 	getnodedata(sfs, &pn->pn_po, localbuf, &sz);
723 	if ((ssize_t)sz < offset)
724 		xfer = 0;
725 	else
726 		xfer = MIN(*resid, sz - offset);
727 
728 	if (xfer <= 0)
729 		return 0;
730 
731 	memcpy(buf, localbuf + offset, xfer);
732 	*resid -= xfer;
733 
734 	if (*resid && !rflag) {
735 		buf[xfer] = '\n';
736 		(*resid)--;
737 	}
738 
739 	return 0;
740 }
741 
742 int
sysctlfs_node_write(struct puffs_usermount * pu,void * opc,uint8_t * buf,off_t offset,size_t * resid,const struct puffs_cred * cred,int ioflag)743 sysctlfs_node_write(struct puffs_usermount *pu, void *opc, uint8_t *buf,
744 	off_t offset, size_t *resid, const struct puffs_cred *cred,
745 	int ioflag)
746 {
747 	struct puffs_node *pn = opc;
748 	struct sfsnode *sfs = pn->pn_data;
749 	long long ll;
750 	int i, rv;
751 	bool b;
752 
753 	/*
754 	 * I picked the wrong day to ... um, the wrong place to return errors
755 	 */
756 
757 	/* easy to support, but just unavailable now */
758 	if (rflag)
759 		return EOPNOTSUPP;
760 
761 	if (puffs_cred_isjuggernaut(cred) == 0)
762 		return EACCES;
763 
764 	if (ISADIR(sfs))
765 		return EISDIR;
766 
767 	if (offset != 0)
768 		return EINVAL;
769 
770 	if (ioflag & PUFFS_IO_APPEND)
771 		return EINVAL;
772 
773 	switch (SYSCTL_TYPE(sfs->sysctl_flags)) {
774 	case CTLTYPE_BOOL:
775 		if (strcasestr((const char *)buf, "true"))
776 			b = true;
777 		else if (strcasestr((const char *)buf, "false"))
778 			b = false;
779 		else
780 			return EINVAL;
781 		rv = sysctl(PNPATH(pn), PNPLEN(pn), NULL, NULL,
782 		    &b, sizeof(b));
783 		break;
784 	case CTLTYPE_INT:
785 		if (sscanf((const char *)buf, "%d", &i) != 1)
786 			return EINVAL;
787 		rv = sysctl(PNPATH(pn), PNPLEN(pn), NULL, NULL,
788 		    &i, sizeof(int));
789 		break;
790 	case CTLTYPE_QUAD:
791 		if (sscanf((const char *)buf, "%lld", &ll) != 1)
792 			return EINVAL;
793 		rv =  sysctl(PNPATH(pn), PNPLEN(pn), NULL, NULL,
794 		    &ll, sizeof(long long));
795 		break;
796 	case CTLTYPE_STRING:
797 		rv = sysctl(PNPATH(pn), PNPLEN(pn), NULL, NULL, buf, *resid);
798 		break;
799 	default:
800 		rv = EINVAL;
801 		break;
802 	}
803 
804 	if (rv)
805 		return rv;
806 
807 	*resid = 0;
808 	return 0;
809 }
810