xref: /netbsd-src/usr.bin/pmap/main.c (revision 946379e7b37692fc43f68eb0d1c10daa0a7f3b6c)
1 /*	$NetBSD: main.c,v 1.26 2015/12/14 03:15:10 christos Exp $ */
2 
3 /*
4  * Copyright (c) 2002, 2003 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Andrew Brown.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #ifndef lint
34 __RCSID("$NetBSD: main.c,v 1.26 2015/12/14 03:15:10 christos Exp $");
35 #endif
36 
37 #include <sys/param.h>
38 
39 #ifndef __NetBSD_Version__
40 #error go away, you fool
41 #elif (__NetBSD_Version__ < 105000000)
42 #error only works with uvm
43 #endif
44 
45 #include <fcntl.h>
46 #include <errno.h>
47 #include <unistd.h>
48 #include <limits.h>
49 #include <string.h>
50 #include <signal.h>
51 #include <util.h>
52 
53 #include "pmap.h"
54 #include "main.h"
55 
56 struct cache_head lcache;
57 struct nchashhead *nchashtbl;
58 void *uvm_vnodeops, *uvm_deviceops, *aobj_pager, *ubc_pager;
59 struct vm_map *kmem_map, *mb_map, *phys_map, *exec_map, *pager_map;
60 struct vm_map *st_map, *pt_map, *lkm_map, *buf_map;
61 u_long nchash_addr, nchashtbl_addr, kernel_map_addr;
62 int debug, verbose, recurse, page_size;
63 int print_all, print_map, print_maps, print_solaris, print_ddb;
64 rlim_t maxssiz;
65 
66 struct nlist ksyms[] = {
67 	{ "_maxsmap", 0, 0, 0, 0 },
68 #define NL_MAXSSIZ		0
69 	{ "_uvm_vnodeops", 0, 0, 0, 0 },
70 #define NL_UVM_VNODEOPS		1
71 	{ "_uvm_deviceops", 0, 0, 0, 0 },
72 #define NL_UVM_DEVICEOPS	2
73 	{ "_aobj_pager", 0, 0, 0, 0 },
74 #define NL_AOBJ_PAGER		3
75 	{ "_ubc_pager", 0, 0, 0, 0 },
76 #define NL_UBC_PAGER		4
77 	{ "_kernel_map", 0, 0, 0, 0 },
78 #define NL_KERNEL_MAP		5
79 	{ "_nchashtbl", 0, 0, 0, 0 },
80 #define NL_NCHASHTBL		6
81 	{ "_nchash", 0, 0, 0, 0 },
82 #define NL_NCHASH		7
83 	{ NULL, 0, 0, 0, 0 }
84 };
85 
86 struct nlist kmaps[] = {
87 	{ "_kmem_map", 0, 0, 0, 0 },
88 #define NL_kmem_map		0
89 	{ "_mb_map", 0, 0, 0, 0 },
90 #define NL_mb_map		1
91 	{ "_phys_map", 0, 0, 0, 0 },
92 #define NL_phys_map		2
93 	{ "_exec_map", 0, 0, 0, 0 },
94 #define NL_exec_map		3
95 	{ "_pager_map", 0, 0, 0, 0 },
96 #define NL_pager_map		4
97 	{ "_st_map", 0, 0, 0, 0 },
98 #define NL_st_map		5
99 	{ "_pt_map", 0, 0, 0, 0 },
100 #define NL_pt_map		6
101 	{ "_lkm_map", 0, 0, 0, 0 },
102 #define NL_lkm_map		7
103 	{ "_buf_map", 0, 0, 0, 0 },
104 #define NL_buf_map		8
105 	{ NULL, 0, 0, 0, 0 },
106 };
107 
108 #define VMSPACE_ADDRESS		1
109 #define VM_MAP_ADDRESS		2
110 #define VM_MAP_ENTRY_ADDRESS	3
111 #define AMAP_ADDRESS		4
112 
113 void check_fd(int);
114 void load_symbols(kvm_t *);
115 void cache_enter(u_long, struct namecache *);
116 
117 int
118 main(int argc, char *argv[])
119 {
120 	kvm_t *kd;
121 	pid_t pid;
122 	uid_t uid;
123 	int which, many, ch, rc;
124 	char errbuf[_POSIX2_LINE_MAX + 1];
125 	struct kinfo_proc2 *kproc;
126 	char *kmem, *kernel, *t;
127 	gid_t egid;
128 	struct kbit kbit, *vmspace;
129 	u_long address;
130 
131 	egid = getegid();
132 	if (setegid(getgid()) == -1)
133 		err(1, "failed to reset privileges");
134 
135 	check_fd(STDIN_FILENO);
136 	check_fd(STDOUT_FILENO);
137 	check_fd(STDERR_FILENO);
138 
139 	pid = -1;
140 	which = verbose = debug = 0;
141 	print_all = print_map = print_maps = print_solaris = print_ddb = 0;
142 	recurse = 0;
143 	kmem = kernel = NULL;
144 	address = 0;
145 	vmspace = &kbit;
146 
147 	while ((ch = getopt(argc, argv, "A:aD:dE:lM:mN:Pp:RrS:sV:vx")) != -1) {
148 		switch (ch) {
149 		case 'A':
150 		case 'E':
151 		case 'S':
152 		case 'V':
153 			if (which != 0)
154 				errx(1, "use only one of -A, -E, -S, or -V");
155 			errno = 0;
156 			address = strtoul(optarg, &t, 0);
157 			if (*t != '\0')
158 				errx(1, "%s is not a valid address", optarg);
159 			if (errno != 0)
160 				err(1, "%s is not a valid address", optarg);
161 			switch (ch) {
162 			case 'A':	which = AMAP_ADDRESS;		break;
163 			case 'E':	which = VM_MAP_ENTRY_ADDRESS;	break;
164 			case 'S':	which = VMSPACE_ADDRESS;	break;
165 			case 'V':	which = VM_MAP_ADDRESS;		break;
166 			}
167 			break;
168 		case 'a':
169 			print_all = 1;
170 			break;
171 		case 'd':
172 			print_ddb = 1;
173 			break;
174 		case 'D':
175 			errno = 0;
176 			debug = strtoul(optarg, &t, 0);
177 			if (*t != '\0')
178 				errx(1, "%s is not a valid number", optarg);
179 			if (errno != 0)
180 				err(1, "%s is not a valid number", optarg);
181 			break;
182 		case 'l':
183 			print_maps = 1;
184 			break;
185 		case 'm':
186 			print_map = 1;
187 			break;
188 		case 'M':
189 			kmem = optarg;
190 			break;
191 		case 'N':
192 			kernel = optarg;
193 			break;
194 		case 'p':
195 			errno = 0;
196 			pid = strtol(optarg, &t, 0);
197 			if (pid < 0)
198 				errno = EINVAL;
199 			if (*t != '\0')
200 				errx(1, "%s is not a valid pid", optarg);
201 			if (errno != 0)
202 				err(1, "%s is not a valid pid", optarg);
203 			break;
204 		case 'P':
205 			pid = getpid();
206 			break;
207 		case 'R':
208 			recurse = 1;
209 			break;
210 		case 's':
211 			print_solaris = 1;
212 			break;
213 		case 'v':
214 			verbose++;
215 			break;
216 		case 'r':
217 		case 'x':
218 			errx(1, "-%c option not implemented, sorry", optopt);
219 			/*NOTREACHED*/
220 		case '?':
221 		default:
222 			fprintf(stderr, "usage: %s [-adlmPRsv] [-A address] "
223 				"[-D number] [-E address] [-M core]\n"
224 				"\t[-N system] [-p pid] [-S address] "
225 				"[-V address] [pid ...]\n",
226 				getprogname());
227 			exit(1);
228 		}
229 	}
230 	argc -= optind;
231 	argv += optind;
232 
233 	/* more than one "process" to dump? */
234 	many = (argc > 1 - (pid == -1 ? 0 : 1)) ? 1 : 0;
235 
236 	/* apply default */
237 	if (print_all + print_map + print_maps + print_solaris +
238 	    print_ddb == 0)
239 		print_solaris = 1;
240 
241 	/* get privs back if it appears to be safe, otherwise toss them */
242 	if (kernel == NULL && kmem == NULL && address == 0)
243 		rc = setegid(egid);
244 	else
245 		rc = setgid(getgid());
246 	if (rc == -1)
247 		err(1, "failed to reset privileges");
248 
249 	/* start by opening libkvm */
250 	kd = kvm_openfiles(kernel, kmem, NULL, O_RDONLY, errbuf);
251 
252 	/* we're completely done with privileges now */
253 	rc = setgid(getgid());
254 	if (rc == -1)
255 		err(1, "failed to reset privileges");
256 
257 	/* print the kvm_open error, if any */
258 	errbuf[_POSIX2_LINE_MAX] = '\0';
259 	if (kd == NULL)
260 		errx(1, "%s", errbuf);
261 
262 	/* get "bootstrap" addresses from kernel */
263 	load_symbols(kd);
264 
265 	if (address) {
266 		struct kbit kbit2, *at = &kbit2;
267 
268 		memset(vmspace, 0, sizeof(*vmspace));
269 		A(at) = address;
270 		S(at) = (size_t)-1;
271 
272 		switch (which) {
273 		    case VMSPACE_ADDRESS:
274 			/* (kd, kproc, vmspace, thing) */
275 			(*process_map)(kd, NULL, at, "vm_map");
276 			break;
277 		    case VM_MAP_ADDRESS:
278 			/* (kd, proc, vmspace, vm_map, thing) */
279 			(*dump_vm_map)(kd, NULL, vmspace, at, "vm_map");
280 			break;
281 		    case VM_MAP_ENTRY_ADDRESS:
282 			/* (kd, proc, vmspace, vm_map_entry, 0) */
283 			(*dump_vm_map_entry)(kd, NULL, vmspace, at, 0);
284 			break;
285 		    case AMAP_ADDRESS:
286 			/* (kd, amap) */
287 			(*dump_amap)(kd, at);
288 			break;
289 		}
290 		exit(0);
291 	}
292 
293 	uid = getuid();
294 
295 	do {
296 		if (pid == -1) {
297 			if (argc == 0)
298 				pid = getppid();
299 			else {
300 				errno = 0;
301 				pid = strtol(argv[0], &t, 0);
302 				if (pid < 0)
303 					errno = EINVAL;
304 				if (*t != '\0')
305 					errx(1, "%s is not a valid pid",
306 					    argv[0]);
307 				if (errno != 0)
308 					err(1, "%s is not a valid pid",
309 					    argv[0]);
310 				argv++;
311 				argc--;
312 			}
313 		}
314 
315 		errno = 0;
316 		/* find the process id */
317 		if (pid == 0) {
318 			kproc = NULL;
319 			if (uid != 0) {
320 				/* only root can print kernel mappings */
321 				errno = EPERM;
322 			}
323 		} else {
324 			kproc = kvm_getproc2(kd, KERN_PROC_PID, pid,
325 			    sizeof(struct kinfo_proc2), &rc);
326 			if (kproc == NULL || rc == 0) {
327 				errno = ESRCH;
328 			} else if (uid != 0 && uid != kproc->p_uid) {
329 				/*
330 				 * only the real owner of the process and
331 				 * root can print process mappings
332 				 */
333 				errno = EPERM;
334 			}
335 		}
336 
337 		if (errno != 0) {
338 			warn("%d", pid);
339 			pid = -1;
340 			continue;
341 		}
342 
343 		/* dump it */
344 		if (many) {
345 			if (kproc != NULL)
346 				printf("process %d:\n", kproc->p_pid);
347 			else
348 				printf("kernel:\n");
349 		}
350 
351 		(*process_map)(kd, kproc, vmspace, NULL);
352 		pid = -1;
353 	} while (argc > 0);
354 
355 	/* done.  go away. */
356 	rc = kvm_close(kd);
357 	if (rc == -1)
358 		err(1, "kvm_close");
359 
360 	return (0);
361 }
362 
363 void
364 check_fd(int fd)
365 {
366 	struct stat st;
367 	int n;
368 
369 	if (fstat(fd, &st) == -1) {
370 		(void)close(fd);
371 		n = open("/dev/null", O_RDWR);
372 		if (n == fd || n == -1)
373 			/* we're either done or we can do no more */
374 			return;
375 		/* if either of these fail, there's not much we can do */
376 		(void)dup2(n, fd);
377 		(void)close(n);
378 		/* XXX should we exit if it fails? */
379 	}
380 }
381 
382 void
383 load_symbols(kvm_t *kd)
384 {
385 	int rc, i, mib[2];
386 	size_t sz;
387 
388 	rc = kvm_nlist(kd, &ksyms[0]);
389 	if (rc != 0) {
390 		for (i = 0; ksyms[i].n_name != NULL; i++)
391 			if (ksyms[i].n_value == 0)
392 				warnx("symbol %s: not found", ksyms[i].n_name);
393 		exit(1);
394 	}
395 
396 	uvm_vnodeops =	(void*)ksyms[NL_UVM_VNODEOPS].n_value;
397 	uvm_deviceops =	(void*)ksyms[NL_UVM_DEVICEOPS].n_value;
398 	aobj_pager =	(void*)ksyms[NL_AOBJ_PAGER].n_value;
399 	ubc_pager =	(void*)ksyms[NL_UBC_PAGER].n_value;
400 
401 	nchash_addr =	ksyms[NL_NCHASH].n_value;
402 
403 	_KDEREF(kd, ksyms[NL_MAXSSIZ].n_value, &maxssiz,
404 		sizeof(maxssiz));
405 	_KDEREF(kd, ksyms[NL_NCHASHTBL].n_value, &nchashtbl_addr,
406 	       sizeof(nchashtbl_addr));
407 	_KDEREF(kd, ksyms[NL_KERNEL_MAP].n_value, &kernel_map_addr,
408 		sizeof(kernel_map_addr));
409 
410 	/*
411 	 * Some of these may be missing from some platforms, for
412 	 * example sparc, sh3, and most powerpc platforms don't
413 	 * have a "phys_map", etc.
414 	 */
415 	(void)kvm_nlist(kd, &kmaps[0]);
416 
417 #define get_map_address(m) do {\
418 	if (kmaps[__CONCAT(NL_,m)].n_value != 0) \
419 		_KDEREF(kd, kmaps[__CONCAT(NL_,m)].n_value, &m, sizeof(m)); \
420 	} while (0/*CONSTCOND*/)
421 
422 	get_map_address(kmem_map);
423 	get_map_address(mb_map);
424 	get_map_address(phys_map);
425 	get_map_address(exec_map);
426 	get_map_address(pager_map);
427 	get_map_address(st_map);
428 	get_map_address(pt_map);
429 	get_map_address(lkm_map);
430 	get_map_address(buf_map);
431 
432 	mib[0] = CTL_HW;
433 	mib[1] = HW_PAGESIZE;
434 	sz = sizeof(page_size);
435 	if (sysctl(&mib[0], 2, &page_size, &sz, NULL, 0) == -1)
436 		err(1, "sysctl: hw.pagesize");
437 }
438 
439 const char *
440 mapname(void *addr)
441 {
442 
443 	if (addr == (void*)kernel_map_addr)
444 		return ("kernel_map");
445 	else if (addr == kmem_map)
446 		return ("kmem_map");
447 	else if (addr == mb_map)
448 		return ("mb_map");
449 	else if (addr == phys_map)
450 		return ("phys_map");
451 	else if (addr == exec_map)
452 		return ("exec_map");
453 	else if (addr == pager_map)
454 		return ("pager_map");
455 	else if (addr == st_map)
456 		return ("st_map");
457 	else if (addr == pt_map)
458 		return ("pt_map");
459 	else if (addr == lkm_map)
460 		return ("lkm_map");
461 	else if (addr == buf_map)
462 		return ("buf_map");
463 	else
464 		return (NULL);
465 }
466 
467 void
468 load_name_cache(kvm_t *kd)
469 {
470 	struct namecache _ncp, *ncp, *oncp;
471 	struct nchashhead _ncpp, *ncpp;
472 	u_long lnchash;
473 	size_t nchash, i;
474 
475 	LIST_INIT(&lcache);
476 
477 	_KDEREF(kd, nchash_addr, &lnchash, sizeof(lnchash));
478 	nchash = (size_t)lnchash + 1;
479 	nchashtbl = ecalloc(nchash, sizeof(*nchashtbl));
480 	_KDEREF(kd, nchashtbl_addr, nchashtbl, sizeof(*nchashtbl) * nchash);
481 
482 	ncpp = &_ncpp;
483 
484 	for (i = 0; i < nchash; i++) {
485 		ncpp = &nchashtbl[i];
486 		oncp = NULL;
487 		LIST_FOREACH(ncp, ncpp, nc_hash) {
488 			if (ncp == oncp ||
489 			    ncp == (void*)0xdeadbeef)
490 				break;
491 			oncp = ncp;
492 			_KDEREF(kd, (u_long)ncp, &_ncp, sizeof(*ncp));
493 			ncp = &_ncp;
494 			if (ncp->nc_nlen > 0) {
495 				if (ncp->nc_nlen > 2 ||
496 				    ncp->nc_name[0] != '.' ||
497 				    (ncp->nc_name[1] != '.' &&
498 				     ncp->nc_nlen != 1))
499 					cache_enter(i, ncp);
500 			}
501 		}
502 	}
503 }
504 
505 void
506 cache_enter(u_long i, struct namecache *ncp)
507 {
508 	struct cache_entry *ce;
509 
510 	if (debug & DUMP_NAMEI_CACHE)
511 		printf("[%lu] ncp->nc_vp %10p, ncp->nc_dvp %10p, "
512 		       "ncp->nc_nlen %3d [%.*s]\n",
513 		       i, ncp->nc_vp, ncp->nc_dvp,
514 		       ncp->nc_nlen, ncp->nc_nlen, ncp->nc_name);
515 
516 	ce = emalloc(sizeof(struct cache_entry));
517 
518 	ce->ce_vp = ncp->nc_vp;
519 	ce->ce_pvp = ncp->nc_dvp;
520 	ce->ce_nlen = ncp->nc_nlen;
521 	strncpy(ce->ce_name, ncp->nc_name, sizeof(ce->ce_name));
522 	ce->ce_name[MIN(ce->ce_nlen, (int)(sizeof(ce->ce_name) - 1))] = '\0';
523 
524 	LIST_INSERT_HEAD(&lcache, ce, ce_next);
525 }
526