kvm_proc.c revision 1.20
1 /* $NetBSD: kvm_proc.c,v 1.20 1997/08/15 17:52:46 drochner Exp $ */ 2 3 /*- 4 * Copyright (c) 1994, 1995 Charles M. Hannum. All rights reserved. 5 * Copyright (c) 1989, 1992, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software developed by the Computer Systems 9 * Engineering group at Lawrence Berkeley Laboratory under DARPA contract 10 * BG 91-66 and contributed to Berkeley. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by the University of 23 * California, Berkeley and its contributors. 24 * 4. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 */ 40 41 #include <sys/cdefs.h> 42 #if defined(LIBC_SCCS) && !defined(lint) 43 #if 0 44 static char sccsid[] = "@(#)kvm_proc.c 8.3 (Berkeley) 9/23/93"; 45 #else 46 __RCSID("$NetBSD: kvm_proc.c,v 1.20 1997/08/15 17:52:46 drochner Exp $"); 47 #endif 48 #endif /* LIBC_SCCS and not lint */ 49 50 /* 51 * Proc traversal interface for kvm. ps and w are (probably) the exclusive 52 * users of this code, so we've factored it out into a separate module. 53 * Thus, we keep this grunge out of the other kvm applications (i.e., 54 * most other applications are interested only in open/close/read/nlist). 55 */ 56 57 #include <sys/param.h> 58 #include <sys/user.h> 59 #include <sys/proc.h> 60 #include <sys/exec.h> 61 #include <sys/stat.h> 62 #include <sys/ioctl.h> 63 #include <sys/tty.h> 64 #include <stdlib.h> 65 #include <string.h> 66 #include <unistd.h> 67 #include <nlist.h> 68 #include <kvm.h> 69 70 #include <vm/vm.h> 71 #include <vm/vm_param.h> 72 #include <vm/swap_pager.h> 73 74 #include <sys/sysctl.h> 75 76 #include <limits.h> 77 #include <db.h> 78 #include <paths.h> 79 80 #include "kvm_private.h" 81 82 #define KREAD(kd, addr, obj) \ 83 (kvm_read(kd, addr, (char *)(obj), sizeof(*obj)) != sizeof(*obj)) 84 85 char *_kvm_uread __P((kvm_t *, const struct proc *, u_long, u_long *)); 86 int _kvm_coreinit __P((kvm_t *)); 87 int _kvm_readfromcore __P((kvm_t *, u_long, u_long)); 88 int _kvm_readfrompager __P((kvm_t *, struct vm_object *, u_long)); 89 ssize_t kvm_uread __P((kvm_t *, const struct proc *, u_long, char *, 90 size_t)); 91 92 static char **kvm_argv __P((kvm_t *, const struct proc *, u_long, int, 93 int)); 94 static int kvm_deadprocs __P((kvm_t *, int, int, u_long, u_long, int)); 95 static char **kvm_doargv __P((kvm_t *, const struct kinfo_proc *, int, 96 void (*)(struct ps_strings *, u_long *, int *))); 97 static int kvm_proclist __P((kvm_t *, int, int, struct proc *, 98 struct kinfo_proc *, int)); 99 static int proc_verify __P((kvm_t *, u_long, const struct proc *)); 100 static void ps_str_a __P((struct ps_strings *, u_long *, int *)); 101 static void ps_str_e __P((struct ps_strings *, u_long *, int *)); 102 103 char * 104 _kvm_uread(kd, p, va, cnt) 105 kvm_t *kd; 106 const struct proc *p; 107 u_long va; 108 u_long *cnt; 109 { 110 register u_long addr, head; 111 register u_long offset; 112 struct vm_map_entry vme; 113 struct vm_object vmo; 114 int rv; 115 116 if (kd->swapspc == 0) { 117 kd->swapspc = (char *)_kvm_malloc(kd, kd->nbpg); 118 if (kd->swapspc == 0) 119 return (0); 120 } 121 122 /* 123 * Look through the address map for the memory object 124 * that corresponds to the given virtual address. 125 * The header just has the entire valid range. 126 */ 127 head = (u_long)&p->p_vmspace->vm_map.header; 128 addr = head; 129 while (1) { 130 if (KREAD(kd, addr, &vme)) 131 return (0); 132 133 if (va >= vme.start && va < vme.end && 134 vme.object.vm_object != 0) 135 break; 136 137 addr = (u_long)vme.next; 138 if (addr == head) 139 return (0); 140 } 141 142 /* 143 * We found the right object -- follow shadow links. 144 */ 145 offset = va - vme.start + vme.offset; 146 addr = (u_long)vme.object.vm_object; 147 148 while (1) { 149 /* Try reading the page from core first. */ 150 if ((rv = _kvm_readfromcore(kd, addr, offset))) 151 break; 152 153 if (KREAD(kd, addr, &vmo)) 154 return (0); 155 156 /* If there is a pager here, see if it has the page. */ 157 if (vmo.pager != 0 && 158 (rv = _kvm_readfrompager(kd, &vmo, offset))) 159 break; 160 161 /* Move down the shadow chain. */ 162 addr = (u_long)vmo.shadow; 163 if (addr == 0) 164 return (0); 165 offset += vmo.shadow_offset; 166 } 167 168 if (rv == -1) 169 return (0); 170 171 /* Found the page. */ 172 offset %= kd->nbpg; 173 *cnt = kd->nbpg - offset; 174 return (&kd->swapspc[offset]); 175 } 176 177 #define vm_page_hash(kd, object, offset) \ 178 (((u_long)object + (u_long)(offset / kd->nbpg)) & kd->vm_page_hash_mask) 179 180 int 181 _kvm_coreinit(kd) 182 kvm_t *kd; 183 { 184 struct nlist nlist[3]; 185 186 nlist[0].n_name = "_vm_page_buckets"; 187 nlist[1].n_name = "_vm_page_hash_mask"; 188 nlist[2].n_name = 0; 189 if (kvm_nlist(kd, nlist) != 0) 190 return (-1); 191 192 if (KREAD(kd, nlist[0].n_value, &kd->vm_page_buckets) || 193 KREAD(kd, nlist[1].n_value, &kd->vm_page_hash_mask)) 194 return (-1); 195 196 return (0); 197 } 198 199 int 200 _kvm_readfromcore(kd, object, offset) 201 kvm_t *kd; 202 u_long object, offset; 203 { 204 u_long addr; 205 struct pglist bucket; 206 struct vm_page mem; 207 off_t seekpoint; 208 209 if (kd->vm_page_buckets == 0 && 210 _kvm_coreinit(kd)) 211 return (-1); 212 213 addr = (u_long)&kd->vm_page_buckets[vm_page_hash(kd, object, offset)]; 214 if (KREAD(kd, addr, &bucket)) 215 return (-1); 216 217 addr = (u_long)bucket.tqh_first; 218 offset &= ~(kd->nbpg -1); 219 while (1) { 220 if (addr == 0) 221 return (0); 222 223 if (KREAD(kd, addr, &mem)) 224 return (-1); 225 226 if ((u_long)mem.object == object && 227 (u_long)mem.offset == offset) 228 break; 229 230 addr = (u_long)mem.hashq.tqe_next; 231 } 232 233 seekpoint = mem.phys_addr; 234 235 if (lseek(kd->pmfd, seekpoint, 0) == -1) 236 return (-1); 237 if (read(kd->pmfd, kd->swapspc, kd->nbpg) != kd->nbpg) 238 return (-1); 239 240 return (1); 241 } 242 243 int 244 _kvm_readfrompager(kd, vmop, offset) 245 kvm_t *kd; 246 struct vm_object *vmop; 247 u_long offset; 248 { 249 u_long addr; 250 struct pager_struct pager; 251 struct swpager swap; 252 int ix; 253 struct swblock swb; 254 off_t seekpoint; 255 256 /* Read in the pager info and make sure it's a swap device. */ 257 addr = (u_long)vmop->pager; 258 if (KREAD(kd, addr, &pager) || pager.pg_type != PG_SWAP) 259 return (-1); 260 261 /* Read in the swap_pager private data. */ 262 addr = (u_long)pager.pg_data; 263 if (KREAD(kd, addr, &swap)) 264 return (-1); 265 266 /* 267 * Calculate the paging offset, and make sure it's within the 268 * bounds of the pager. 269 */ 270 offset += vmop->paging_offset; 271 ix = offset / dbtob(swap.sw_bsize); 272 #if 0 273 if (swap.sw_blocks == 0 || ix >= swap.sw_nblocks) 274 return (-1); 275 #else 276 if (swap.sw_blocks == 0 || ix >= swap.sw_nblocks) { 277 int i; 278 printf("BUG BUG BUG BUG:\n"); 279 printf("object %p offset %lx pgoffset %lx ", 280 vmop, offset - vmop->paging_offset, 281 (u_long)vmop->paging_offset); 282 printf("pager %p swpager %p\n", 283 vmop->pager, pager.pg_data); 284 printf("osize %lx bsize %x blocks %p nblocks %x\n", 285 (u_long)swap.sw_osize, swap.sw_bsize, swap.sw_blocks, 286 swap.sw_nblocks); 287 for (i = 0; i < swap.sw_nblocks; i++) { 288 addr = (u_long)&swap.sw_blocks[i]; 289 if (KREAD(kd, addr, &swb)) 290 return (0); 291 printf("sw_blocks[%d]: block %x mask %x\n", i, 292 swb.swb_block, swb.swb_mask); 293 } 294 return (-1); 295 } 296 #endif 297 298 /* Read in the swap records. */ 299 addr = (u_long)&swap.sw_blocks[ix]; 300 if (KREAD(kd, addr, &swb)) 301 return (-1); 302 303 /* Calculate offset within pager. */ 304 offset %= dbtob(swap.sw_bsize); 305 306 /* Check that the page is actually present. */ 307 if ((swb.swb_mask & (1 << (offset / kd->nbpg))) == 0) 308 return (0); 309 310 if (!ISALIVE(kd)) 311 return (-1); 312 313 /* Calculate the physical address and read the page. */ 314 seekpoint = dbtob(swb.swb_block) + (offset & ~(kd->nbpg -1)); 315 316 if (lseek(kd->swfd, seekpoint, 0) == -1) 317 return (-1); 318 if (read(kd->swfd, kd->swapspc, kd->nbpg) != kd->nbpg) 319 return (-1); 320 321 return (1); 322 } 323 324 /* 325 * Read proc's from memory file into buffer bp, which has space to hold 326 * at most maxcnt procs. 327 */ 328 static int 329 kvm_proclist(kd, what, arg, p, bp, maxcnt) 330 kvm_t *kd; 331 int what, arg; 332 struct proc *p; 333 struct kinfo_proc *bp; 334 int maxcnt; 335 { 336 register int cnt = 0; 337 struct eproc eproc; 338 struct pgrp pgrp; 339 struct session sess; 340 struct tty tty; 341 struct proc proc; 342 343 for (; cnt < maxcnt && p != NULL; p = proc.p_list.le_next) { 344 if (KREAD(kd, (u_long)p, &proc)) { 345 _kvm_err(kd, kd->program, "can't read proc at %x", p); 346 return (-1); 347 } 348 if (KREAD(kd, (u_long)proc.p_cred, &eproc.e_pcred) == 0) 349 (void)KREAD(kd, (u_long)eproc.e_pcred.pc_ucred, 350 &eproc.e_ucred); 351 352 switch(what) { 353 354 case KERN_PROC_PID: 355 if (proc.p_pid != (pid_t)arg) 356 continue; 357 break; 358 359 case KERN_PROC_UID: 360 if (eproc.e_ucred.cr_uid != (uid_t)arg) 361 continue; 362 break; 363 364 case KERN_PROC_RUID: 365 if (eproc.e_pcred.p_ruid != (uid_t)arg) 366 continue; 367 break; 368 } 369 /* 370 * We're going to add another proc to the set. If this 371 * will overflow the buffer, assume the reason is because 372 * nprocs (or the proc list) is corrupt and declare an error. 373 */ 374 if (cnt >= maxcnt) { 375 _kvm_err(kd, kd->program, "nprocs corrupt"); 376 return (-1); 377 } 378 /* 379 * gather eproc 380 */ 381 eproc.e_paddr = p; 382 if (KREAD(kd, (u_long)proc.p_pgrp, &pgrp)) { 383 _kvm_err(kd, kd->program, "can't read pgrp at %x", 384 proc.p_pgrp); 385 return (-1); 386 } 387 eproc.e_sess = pgrp.pg_session; 388 eproc.e_pgid = pgrp.pg_id; 389 eproc.e_jobc = pgrp.pg_jobc; 390 if (KREAD(kd, (u_long)pgrp.pg_session, &sess)) { 391 _kvm_err(kd, kd->program, "can't read session at %x", 392 pgrp.pg_session); 393 return (-1); 394 } 395 if ((proc.p_flag & P_CONTROLT) && sess.s_ttyp != NULL) { 396 if (KREAD(kd, (u_long)sess.s_ttyp, &tty)) { 397 _kvm_err(kd, kd->program, 398 "can't read tty at %x", sess.s_ttyp); 399 return (-1); 400 } 401 eproc.e_tdev = tty.t_dev; 402 eproc.e_tsess = tty.t_session; 403 if (tty.t_pgrp != NULL) { 404 if (KREAD(kd, (u_long)tty.t_pgrp, &pgrp)) { 405 _kvm_err(kd, kd->program, 406 "can't read tpgrp at &x", 407 tty.t_pgrp); 408 return (-1); 409 } 410 eproc.e_tpgid = pgrp.pg_id; 411 } else 412 eproc.e_tpgid = -1; 413 } else 414 eproc.e_tdev = NODEV; 415 eproc.e_flag = sess.s_ttyvp ? EPROC_CTTY : 0; 416 if (sess.s_leader == p) 417 eproc.e_flag |= EPROC_SLEADER; 418 if (proc.p_wmesg) 419 (void)kvm_read(kd, (u_long)proc.p_wmesg, 420 eproc.e_wmesg, WMESGLEN); 421 422 (void)kvm_read(kd, (u_long)proc.p_vmspace, 423 (char *)&eproc.e_vm, sizeof(eproc.e_vm)); 424 425 eproc.e_xsize = eproc.e_xrssize = 0; 426 eproc.e_xccount = eproc.e_xswrss = 0; 427 428 switch (what) { 429 430 case KERN_PROC_PGRP: 431 if (eproc.e_pgid != (pid_t)arg) 432 continue; 433 break; 434 435 case KERN_PROC_TTY: 436 if ((proc.p_flag & P_CONTROLT) == 0 || 437 eproc.e_tdev != (dev_t)arg) 438 continue; 439 break; 440 } 441 bcopy(&proc, &bp->kp_proc, sizeof(proc)); 442 bcopy(&eproc, &bp->kp_eproc, sizeof(eproc)); 443 ++bp; 444 ++cnt; 445 } 446 return (cnt); 447 } 448 449 /* 450 * Build proc info array by reading in proc list from a crash dump. 451 * Return number of procs read. maxcnt is the max we will read. 452 */ 453 static int 454 kvm_deadprocs(kd, what, arg, a_allproc, a_zombproc, maxcnt) 455 kvm_t *kd; 456 int what, arg; 457 u_long a_allproc; 458 u_long a_zombproc; 459 int maxcnt; 460 { 461 register struct kinfo_proc *bp = kd->procbase; 462 register int acnt, zcnt; 463 struct proc *p; 464 465 if (KREAD(kd, a_allproc, &p)) { 466 _kvm_err(kd, kd->program, "cannot read allproc"); 467 return (-1); 468 } 469 acnt = kvm_proclist(kd, what, arg, p, bp, maxcnt); 470 if (acnt < 0) 471 return (acnt); 472 473 if (KREAD(kd, a_zombproc, &p)) { 474 _kvm_err(kd, kd->program, "cannot read zombproc"); 475 return (-1); 476 } 477 zcnt = kvm_proclist(kd, what, arg, p, bp + acnt, maxcnt - acnt); 478 if (zcnt < 0) 479 zcnt = 0; 480 481 return (acnt + zcnt); 482 } 483 484 struct kinfo_proc * 485 kvm_getprocs(kd, op, arg, cnt) 486 kvm_t *kd; 487 int op, arg; 488 int *cnt; 489 { 490 size_t size; 491 int mib[4], st, nprocs; 492 493 if (kd->procbase != 0) { 494 free((void *)kd->procbase); 495 /* 496 * Clear this pointer in case this call fails. Otherwise, 497 * kvm_close() will free it again. 498 */ 499 kd->procbase = 0; 500 } 501 if (ISALIVE(kd)) { 502 size = 0; 503 mib[0] = CTL_KERN; 504 mib[1] = KERN_PROC; 505 mib[2] = op; 506 mib[3] = arg; 507 st = sysctl(mib, 4, NULL, &size, NULL, 0); 508 if (st == -1) { 509 _kvm_syserr(kd, kd->program, "kvm_getprocs"); 510 return (0); 511 } 512 kd->procbase = (struct kinfo_proc *)_kvm_malloc(kd, size); 513 if (kd->procbase == 0) 514 return (0); 515 st = sysctl(mib, 4, kd->procbase, &size, NULL, 0); 516 if (st == -1) { 517 _kvm_syserr(kd, kd->program, "kvm_getprocs"); 518 return (0); 519 } 520 if (size % sizeof(struct kinfo_proc) != 0) { 521 _kvm_err(kd, kd->program, 522 "proc size mismatch (%d total, %d chunks)", 523 size, sizeof(struct kinfo_proc)); 524 return (0); 525 } 526 nprocs = size / sizeof(struct kinfo_proc); 527 } else { 528 struct nlist nl[4], *p; 529 530 nl[0].n_name = "_nprocs"; 531 nl[1].n_name = "_allproc"; 532 nl[2].n_name = "_zombproc"; 533 nl[3].n_name = 0; 534 535 if (kvm_nlist(kd, nl) != 0) { 536 for (p = nl; p->n_type != 0; ++p) 537 ; 538 _kvm_err(kd, kd->program, 539 "%s: no such symbol", p->n_name); 540 return (0); 541 } 542 if (KREAD(kd, nl[0].n_value, &nprocs)) { 543 _kvm_err(kd, kd->program, "can't read nprocs"); 544 return (0); 545 } 546 size = nprocs * sizeof(struct kinfo_proc); 547 kd->procbase = (struct kinfo_proc *)_kvm_malloc(kd, size); 548 if (kd->procbase == 0) 549 return (0); 550 551 nprocs = kvm_deadprocs(kd, op, arg, nl[1].n_value, 552 nl[2].n_value, nprocs); 553 #ifdef notdef 554 size = nprocs * sizeof(struct kinfo_proc); 555 (void)realloc(kd->procbase, size); 556 #endif 557 } 558 *cnt = nprocs; 559 return (kd->procbase); 560 } 561 562 void 563 _kvm_freeprocs(kd) 564 kvm_t *kd; 565 { 566 if (kd->procbase) { 567 free(kd->procbase); 568 kd->procbase = 0; 569 } 570 } 571 572 void * 573 _kvm_realloc(kd, p, n) 574 kvm_t *kd; 575 void *p; 576 size_t n; 577 { 578 void *np = (void *)realloc(p, n); 579 580 if (np == 0) 581 _kvm_err(kd, kd->program, "out of memory"); 582 return (np); 583 } 584 585 #ifndef MAX 586 #define MAX(a, b) ((a) > (b) ? (a) : (b)) 587 #endif 588 589 /* 590 * Read in an argument vector from the user address space of process p. 591 * addr if the user-space base address of narg null-terminated contiguous 592 * strings. This is used to read in both the command arguments and 593 * environment strings. Read at most maxcnt characters of strings. 594 */ 595 static char ** 596 kvm_argv(kd, p, addr, narg, maxcnt) 597 kvm_t *kd; 598 const struct proc *p; 599 register u_long addr; 600 register int narg; 601 register int maxcnt; 602 { 603 register char *np, *cp, *ep, *ap; 604 register u_long oaddr = -1; 605 register int len, cc; 606 register char **argv; 607 608 /* 609 * Check that there aren't an unreasonable number of agruments, 610 * and that the address is in user space. 611 */ 612 if (narg > ARG_MAX || addr < kd->min_uva || addr >= kd->max_uva) 613 return (0); 614 615 if (kd->argv == 0) { 616 /* 617 * Try to avoid reallocs. 618 */ 619 kd->argc = MAX(narg + 1, 32); 620 kd->argv = (char **)_kvm_malloc(kd, kd->argc * 621 sizeof(*kd->argv)); 622 if (kd->argv == 0) 623 return (0); 624 } else if (narg + 1 > kd->argc) { 625 kd->argc = MAX(2 * kd->argc, narg + 1); 626 kd->argv = (char **)_kvm_realloc(kd, kd->argv, kd->argc * 627 sizeof(*kd->argv)); 628 if (kd->argv == 0) 629 return (0); 630 } 631 if (kd->argspc == 0) { 632 kd->argspc = (char *)_kvm_malloc(kd, kd->nbpg); 633 if (kd->argspc == 0) 634 return (0); 635 kd->arglen = kd->nbpg; 636 } 637 if (kd->argbuf == 0) { 638 kd->argbuf = (char *)_kvm_malloc(kd, kd->nbpg); 639 if (kd->argbuf == 0) 640 return (0); 641 } 642 cc = sizeof(char *) * narg; 643 if (kvm_uread(kd, p, addr, (char *)kd->argv, cc) != cc) 644 return (0); 645 ap = np = kd->argspc; 646 argv = kd->argv; 647 len = 0; 648 /* 649 * Loop over pages, filling in the argument vector. 650 */ 651 while (argv < kd->argv + narg && *argv != 0) { 652 addr = (u_long)*argv & ~(kd->nbpg - 1); 653 if (addr != oaddr) { 654 if (kvm_uread(kd, p, addr, kd->argbuf, kd->nbpg) != 655 kd->nbpg) 656 return (0); 657 oaddr = addr; 658 } 659 addr = (u_long)*argv & (kd->nbpg - 1); 660 cp = kd->argbuf + addr; 661 cc = kd->nbpg - addr; 662 if (maxcnt > 0 && cc > maxcnt - len) 663 cc = maxcnt - len;; 664 ep = memchr(cp, '\0', cc); 665 if (ep != 0) 666 cc = ep - cp + 1; 667 if (len + cc > kd->arglen) { 668 register int off; 669 register char **pp; 670 register char *op = kd->argspc; 671 672 kd->arglen *= 2; 673 kd->argspc = (char *)_kvm_realloc(kd, kd->argspc, 674 kd->arglen); 675 if (kd->argspc == 0) 676 return (0); 677 /* 678 * Adjust argv pointers in case realloc moved 679 * the string space. 680 */ 681 off = kd->argspc - op; 682 for (pp = kd->argv; pp < argv; pp++) 683 *pp += off; 684 ap += off; 685 np += off; 686 } 687 memcpy(np, cp, cc); 688 np += cc; 689 len += cc; 690 if (ep != 0) { 691 *argv++ = ap; 692 ap = np; 693 } else 694 *argv += cc; 695 if (maxcnt > 0 && len >= maxcnt) { 696 /* 697 * We're stopping prematurely. Terminate the 698 * current string. 699 */ 700 if (ep == 0) { 701 *np = '\0'; 702 *argv++ = ap; 703 } 704 break; 705 } 706 } 707 /* Make sure argv is terminated. */ 708 *argv = 0; 709 return (kd->argv); 710 } 711 712 static void 713 ps_str_a(p, addr, n) 714 struct ps_strings *p; 715 u_long *addr; 716 int *n; 717 { 718 *addr = (u_long)p->ps_argvstr; 719 *n = p->ps_nargvstr; 720 } 721 722 static void 723 ps_str_e(p, addr, n) 724 struct ps_strings *p; 725 u_long *addr; 726 int *n; 727 { 728 *addr = (u_long)p->ps_envstr; 729 *n = p->ps_nenvstr; 730 } 731 732 /* 733 * Determine if the proc indicated by p is still active. 734 * This test is not 100% foolproof in theory, but chances of 735 * being wrong are very low. 736 */ 737 static int 738 proc_verify(kd, kernp, p) 739 kvm_t *kd; 740 u_long kernp; 741 const struct proc *p; 742 { 743 struct proc kernproc; 744 745 /* 746 * Just read in the whole proc. It's not that big relative 747 * to the cost of the read system call. 748 */ 749 if (kvm_read(kd, kernp, (char *)&kernproc, sizeof(kernproc)) != 750 sizeof(kernproc)) 751 return (0); 752 return (p->p_pid == kernproc.p_pid && 753 (kernproc.p_stat != SZOMB || p->p_stat == SZOMB)); 754 } 755 756 static char ** 757 kvm_doargv(kd, kp, nchr, info) 758 kvm_t *kd; 759 const struct kinfo_proc *kp; 760 int nchr; 761 void (*info)(struct ps_strings *, u_long *, int *); 762 { 763 register const struct proc *p = &kp->kp_proc; 764 register char **ap; 765 u_long addr; 766 int cnt; 767 struct ps_strings arginfo; 768 769 /* 770 * Pointers are stored at the top of the user stack. 771 */ 772 if (p->p_stat == SZOMB) 773 return (0); 774 cnt = kvm_uread(kd, p, kd->usrstack - sizeof(arginfo), 775 (char *)&arginfo, sizeof(arginfo)); 776 if (cnt != sizeof(arginfo)) 777 return (0); 778 779 (*info)(&arginfo, &addr, &cnt); 780 if (cnt == 0) 781 return (0); 782 ap = kvm_argv(kd, p, addr, cnt, nchr); 783 /* 784 * For live kernels, make sure this process didn't go away. 785 */ 786 if (ap != 0 && ISALIVE(kd) && 787 !proc_verify(kd, (u_long)kp->kp_eproc.e_paddr, p)) 788 ap = 0; 789 return (ap); 790 } 791 792 /* 793 * Get the command args. This code is now machine independent. 794 */ 795 char ** 796 kvm_getargv(kd, kp, nchr) 797 kvm_t *kd; 798 const struct kinfo_proc *kp; 799 int nchr; 800 { 801 return (kvm_doargv(kd, kp, nchr, ps_str_a)); 802 } 803 804 char ** 805 kvm_getenvv(kd, kp, nchr) 806 kvm_t *kd; 807 const struct kinfo_proc *kp; 808 int nchr; 809 { 810 return (kvm_doargv(kd, kp, nchr, ps_str_e)); 811 } 812 813 /* 814 * Read from user space. The user context is given by p. 815 */ 816 ssize_t 817 kvm_uread(kd, p, uva, buf, len) 818 kvm_t *kd; 819 register const struct proc *p; 820 register u_long uva; 821 register char *buf; 822 register size_t len; 823 { 824 register char *cp; 825 826 cp = buf; 827 while (len > 0) { 828 register int cc; 829 register char *dp; 830 u_long cnt; 831 832 dp = _kvm_uread(kd, p, uva, &cnt); 833 if (dp == 0) { 834 _kvm_err(kd, 0, "invalid address (%x)", uva); 835 return (0); 836 } 837 cc = MIN(cnt, len); 838 bcopy(dp, cp, cc); 839 840 cp += cc; 841 uva += cc; 842 len -= cc; 843 } 844 return (ssize_t)(cp - buf); 845 } 846
Indexes created Mon Sep 22 10:09:38 GMT 2025