1 /*- 2 * Copyright (c) 1989, 1992, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software developed by the Computer Systems 6 * Engineering group at Lawrence Berkeley Laboratory under DARPA contract 7 * BG 91-66 and contributed to Berkeley. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * $FreeBSD: src/lib/libkvm/kvm_proc.c,v 1.25.2.3 2002/08/24 07:27:46 kris Exp $ 34 * 35 * @(#)kvm_proc.c 8.3 (Berkeley) 9/23/93 36 */ 37 38 /* 39 * Proc traversal interface for kvm. ps and w are (probably) the exclusive 40 * users of this code, so we've factored it out into a separate module. 41 * Thus, we keep this grunge out of the other kvm applications (i.e., 42 * most other applications are interested only in open/close/read/nlist). 43 */ 44 45 #include <sys/user.h> /* MUST BE FIRST */ 46 #include <sys/conf.h> 47 #include <sys/param.h> 48 #include <sys/proc.h> 49 #include <sys/exec.h> 50 #include <sys/stat.h> 51 #include <sys/globaldata.h> 52 #include <sys/ioctl.h> 53 #include <sys/tty.h> 54 #include <sys/file.h> 55 #include <sys/jail.h> 56 #include <stdio.h> 57 #include <stdlib.h> 58 #include <stddef.h> 59 #include <unistd.h> 60 #include <nlist.h> 61 62 #include <vm/vm.h> 63 #include <vm/vm_param.h> 64 #include <vm/swap_pager.h> 65 66 #include <sys/sysctl.h> 67 68 #include <limits.h> 69 #include <memory.h> 70 #include <paths.h> 71 72 #include "kvm.h" 73 #include "kvm_private.h" 74 75 dev_t dev2udev(cdev_t dev); 76 77 #define KREAD(kd, addr, obj) \ 78 (kvm_read(kd, addr, (char *)(obj), sizeof(*obj)) != sizeof(*obj)) 79 #define KREADSTR(kd, addr) \ 80 kvm_readstr(kd, (u_long)addr, NULL, NULL) 81 82 static struct kinfo_proc * 83 kinfo_resize_proc(kvm_t *kd, struct kinfo_proc *bp) 84 { 85 if (bp < kd->procend) 86 return bp; 87 88 size_t pos = bp - kd->procend; 89 size_t size = kd->procend - kd->procbase; 90 91 if (size == 0) 92 size = 8; 93 else 94 size *= 2; 95 kd->procbase = _kvm_realloc(kd, kd->procbase, sizeof(*bp) * size); 96 if (kd->procbase == NULL) 97 return NULL; 98 kd->procend = kd->procbase + size; 99 bp = kd->procbase + pos; 100 return bp; 101 } 102 103 /* 104 * note: this function is also used by /usr/src/sys/kern/kern_kinfo.c as 105 * compiled by userland. 106 */ 107 dev_t 108 dev2udev(cdev_t dev) 109 { 110 if (dev == NULL) 111 return NOUDEV; 112 if ((dev->si_umajor & 0xffffff00) || 113 (dev->si_uminor & 0x0000ff00)) { 114 return NOUDEV; 115 } 116 return((dev->si_umajor << 8) | dev->si_uminor); 117 } 118 119 /* 120 * Helper routine which traverses the left hand side of a red-black sub-tree. 121 */ 122 static uintptr_t 123 kvm_lwptraverse(kvm_t *kd, struct lwp *lwp, uintptr_t lwppos) 124 { 125 for (;;) { 126 if (KREAD(kd, lwppos, lwp)) { 127 _kvm_err(kd, kd->program, "can't read lwp at %p", 128 (void *)lwppos); 129 return ((uintptr_t)-1); 130 } 131 if (lwp->u.lwp_rbnode.rbe_left == NULL) 132 break; 133 lwppos = (uintptr_t)lwp->u.lwp_rbnode.rbe_left; 134 } 135 return(lwppos); 136 } 137 138 /* 139 * Iterate LWPs in a process. 140 * 141 * The first lwp in a red-black tree is a left-side traversal of the tree. 142 */ 143 static uintptr_t 144 kvm_firstlwp(kvm_t *kd, struct lwp *lwp, struct proc *proc) 145 { 146 return(kvm_lwptraverse(kd, lwp, (uintptr_t)proc->p_lwp_tree.rbh_root)); 147 } 148 149 /* 150 * If the current element is the left side of the parent the next element 151 * will be a left side traversal of the parent's right side. If the parent 152 * has no right side the next element will be the parent. 153 * 154 * If the current element is the right side of the parent the next element 155 * is the parent. 156 * 157 * If the parent is NULL we are done. 158 */ 159 static uintptr_t 160 kvm_nextlwp(kvm_t *kd, uintptr_t lwppos, struct lwp *lwp) 161 { 162 uintptr_t nextpos; 163 164 nextpos = (uintptr_t)lwp->u.lwp_rbnode.rbe_parent; 165 if (nextpos) { 166 if (KREAD(kd, nextpos, lwp)) { 167 _kvm_err(kd, kd->program, "can't read lwp at %p", 168 (void *)lwppos); 169 return ((uintptr_t)-1); 170 } 171 if (lwppos == (uintptr_t)lwp->u.lwp_rbnode.rbe_left) { 172 /* 173 * If we had gone down the left side the next element 174 * is a left hand traversal of the parent's right 175 * side, or the parent itself if there is no right 176 * side. 177 */ 178 lwppos = (uintptr_t)lwp->u.lwp_rbnode.rbe_right; 179 if (lwppos) 180 nextpos = kvm_lwptraverse(kd, lwp, lwppos); 181 } else { 182 /* 183 * If we had gone down the right side the next 184 * element is the parent. 185 */ 186 /* nextpos = nextpos */ 187 } 188 } 189 return(nextpos); 190 } 191 192 /* 193 * Read proc's from memory file into buffer bp, which has space to hold 194 * at most maxcnt procs. 195 */ 196 static int 197 kvm_proclist(kvm_t *kd, int what, int arg, struct proc *p, 198 struct kinfo_proc *bp) 199 { 200 struct pgrp pgrp; 201 struct pgrp tpgrp; 202 struct globaldata gdata; 203 struct session sess; 204 struct session tsess; 205 struct tty tty; 206 struct proc proc; 207 struct ucred ucred; 208 struct thread thread; 209 struct proc pproc; 210 struct cdev cdev; 211 struct vmspace vmspace; 212 struct prison prison; 213 struct sigacts sigacts; 214 struct lwp lwp; 215 uintptr_t lwppos; 216 int count; 217 char *wmesg; 218 219 count = 0; 220 221 for (; p != NULL; p = proc.p_list.le_next) { 222 if (KREAD(kd, (u_long)p, &proc)) { 223 _kvm_err(kd, kd->program, "can't read proc at %p", p); 224 return (-1); 225 } 226 if (KREAD(kd, (u_long)proc.p_ucred, &ucred)) { 227 _kvm_err(kd, kd->program, "can't read ucred at %p", 228 proc.p_ucred); 229 return (-1); 230 } 231 proc.p_ucred = &ucred; 232 233 switch(what & ~KERN_PROC_FLAGMASK) { 234 235 case KERN_PROC_PID: 236 if (proc.p_pid != (pid_t)arg) 237 continue; 238 break; 239 240 case KERN_PROC_UID: 241 if (ucred.cr_uid != (uid_t)arg) 242 continue; 243 break; 244 245 case KERN_PROC_RUID: 246 if (ucred.cr_ruid != (uid_t)arg) 247 continue; 248 break; 249 } 250 251 if (KREAD(kd, (u_long)proc.p_pgrp, &pgrp)) { 252 _kvm_err(kd, kd->program, "can't read pgrp at %p", 253 proc.p_pgrp); 254 return (-1); 255 } 256 proc.p_pgrp = &pgrp; 257 if (proc.p_pptr) { 258 if (KREAD(kd, (u_long)proc.p_pptr, &pproc)) { 259 _kvm_err(kd, kd->program, "can't read pproc at %p", 260 proc.p_pptr); 261 return (-1); 262 } 263 proc.p_pptr = &pproc; 264 } 265 266 if (proc.p_sigacts) { 267 if (KREAD(kd, (u_long)proc.p_sigacts, &sigacts)) { 268 _kvm_err(kd, kd->program, 269 "can't read sigacts at %p", 270 proc.p_sigacts); 271 return (-1); 272 } 273 proc.p_sigacts = &sigacts; 274 } 275 276 if (KREAD(kd, (u_long)pgrp.pg_session, &sess)) { 277 _kvm_err(kd, kd->program, "can't read session at %p", 278 pgrp.pg_session); 279 return (-1); 280 } 281 pgrp.pg_session = &sess; 282 283 if ((proc.p_flags & P_CONTROLT) && sess.s_ttyp != NULL) { 284 if (KREAD(kd, (u_long)sess.s_ttyp, &tty)) { 285 _kvm_err(kd, kd->program, 286 "can't read tty at %p", sess.s_ttyp); 287 return (-1); 288 } 289 sess.s_ttyp = &tty; 290 if (tty.t_dev != NULL) { 291 if (KREAD(kd, (u_long)tty.t_dev, &cdev)) 292 tty.t_dev = NULL; 293 else 294 tty.t_dev = &cdev; 295 } 296 if (tty.t_pgrp != NULL) { 297 if (KREAD(kd, (u_long)tty.t_pgrp, &tpgrp)) { 298 _kvm_err(kd, kd->program, 299 "can't read tpgrp at %p", 300 tty.t_pgrp); 301 return (-1); 302 } 303 tty.t_pgrp = &tpgrp; 304 } 305 if (tty.t_session != NULL) { 306 if (KREAD(kd, (u_long)tty.t_session, &tsess)) { 307 _kvm_err(kd, kd->program, 308 "can't read tsess at %p", 309 tty.t_session); 310 return (-1); 311 } 312 tty.t_session = &tsess; 313 } 314 } 315 316 if (KREAD(kd, (u_long)proc.p_vmspace, &vmspace)) { 317 _kvm_err(kd, kd->program, "can't read vmspace at %p", 318 proc.p_vmspace); 319 return (-1); 320 } 321 proc.p_vmspace = &vmspace; 322 323 if (ucred.cr_prison != NULL) { 324 if (KREAD(kd, (u_long)ucred.cr_prison, &prison)) { 325 _kvm_err(kd, kd->program, "can't read prison at %p", 326 ucred.cr_prison); 327 return (-1); 328 } 329 ucred.cr_prison = &prison; 330 } 331 332 switch (what & ~KERN_PROC_FLAGMASK) { 333 334 case KERN_PROC_PGRP: 335 if (proc.p_pgrp->pg_id != (pid_t)arg) 336 continue; 337 break; 338 339 case KERN_PROC_TTY: 340 if ((proc.p_flags & P_CONTROLT) == 0 || 341 dev2udev(proc.p_pgrp->pg_session->s_ttyp->t_dev) 342 != (dev_t)arg) 343 continue; 344 break; 345 } 346 347 if ((bp = kinfo_resize_proc(kd, bp)) == NULL) 348 return (-1); 349 fill_kinfo_proc(&proc, bp); 350 bp->kp_paddr = (uintptr_t)p; 351 352 lwppos = kvm_firstlwp(kd, &lwp, &proc); 353 if (lwppos == 0) { 354 bp++; /* Just export the proc then */ 355 count++; 356 } 357 while (lwppos && lwppos != (uintptr_t)-1) { 358 if (p != lwp.lwp_proc) { 359 _kvm_err(kd, kd->program, "lwp has wrong parent"); 360 return (-1); 361 } 362 lwp.lwp_proc = &proc; 363 if (KREAD(kd, (u_long)lwp.lwp_thread, &thread)) { 364 _kvm_err(kd, kd->program, "can't read thread at %p", 365 lwp.lwp_thread); 366 return (-1); 367 } 368 lwp.lwp_thread = &thread; 369 370 if (thread.td_gd) { 371 if (KREAD(kd, (u_long)thread.td_gd, &gdata)) { 372 _kvm_err(kd, kd->program, "can't read" 373 " gd at %p", 374 thread.td_gd); 375 return(-1); 376 } 377 thread.td_gd = &gdata; 378 } 379 if (thread.td_wmesg) { 380 wmesg = (void *)KREADSTR(kd, thread.td_wmesg); 381 if (wmesg == NULL) { 382 _kvm_err(kd, kd->program, "can't read" 383 " wmesg %p", 384 thread.td_wmesg); 385 return(-1); 386 } 387 thread.td_wmesg = wmesg; 388 } else { 389 wmesg = NULL; 390 } 391 392 if ((bp = kinfo_resize_proc(kd, bp)) == NULL) 393 return (-1); 394 fill_kinfo_proc(&proc, bp); 395 fill_kinfo_lwp(&lwp, &bp->kp_lwp); 396 bp->kp_paddr = (uintptr_t)p; 397 bp++; 398 count++; 399 if (wmesg) 400 free(wmesg); 401 if ((what & KERN_PROC_FLAG_LWP) == 0) 402 break; 403 lwppos = kvm_nextlwp(kd, lwppos, &lwp); 404 } 405 if (lwppos == (uintptr_t)-1) 406 return(-1); 407 } 408 return (count); 409 } 410 411 /* 412 * Build proc info array by reading in proc list from a crash dump. 413 * We reallocate kd->procbase as necessary. 414 */ 415 static int 416 kvm_deadprocs(kvm_t *kd, int what, int arg, int allproc_hsize) 417 { 418 struct kinfo_proc *bp; 419 struct proc *p; 420 struct proclist **pl; 421 int cnt, partcnt, n; 422 u_long nextoff; 423 u_long a_allproc; 424 425 cnt = partcnt = 0; 426 nextoff = 0; 427 428 /* 429 * Dynamically allocate space for all the elements of the 430 * allprocs array and KREAD() them. 431 */ 432 pl = _kvm_malloc(kd, allproc_hsize * sizeof(struct proclist *)); 433 for (n = 0; n < allproc_hsize; n++) { 434 pl[n] = _kvm_malloc(kd, sizeof(struct proclist)); 435 a_allproc = sizeof(struct procglob) * n + 436 offsetof(struct procglob, allproc); 437 nextoff = a_allproc; 438 if (KREAD(kd, (u_long)nextoff, pl[n])) { 439 _kvm_err(kd, kd->program, "can't read proclist at 0x%lx", 440 a_allproc); 441 return (-1); 442 } 443 444 /* Ignore empty proclists */ 445 if (LIST_EMPTY(pl[n])) 446 continue; 447 448 bp = kd->procbase + cnt; 449 p = pl[n]->lh_first; 450 partcnt = kvm_proclist(kd, what, arg, p, bp); 451 if (partcnt < 0) { 452 free(pl[n]); 453 return (partcnt); 454 } 455 456 cnt += partcnt; 457 free(pl[n]); 458 } 459 460 return (cnt); 461 } 462 463 struct kinfo_proc * 464 kvm_getprocs(kvm_t *kd, int op, int arg, int *cnt) 465 { 466 int mib[4], st, nprocs, allproc_hsize; 467 int miblen = ((op & ~KERN_PROC_FLAGMASK) == KERN_PROC_ALL) ? 3 : 4; 468 size_t size; 469 470 if (kd->procbase != 0) { 471 free((void *)kd->procbase); 472 /* 473 * Clear this pointer in case this call fails. Otherwise, 474 * kvm_close() will free it again. 475 */ 476 kd->procbase = 0; 477 } 478 if (kvm_ishost(kd)) { 479 size = 0; 480 mib[0] = CTL_KERN; 481 mib[1] = KERN_PROC; 482 mib[2] = op; 483 mib[3] = arg; 484 st = sysctl(mib, miblen, NULL, &size, NULL, 0); 485 if (st == -1) { 486 _kvm_syserr(kd, kd->program, "kvm_getprocs"); 487 return (0); 488 } 489 do { 490 size += size / 10; 491 kd->procbase = (struct kinfo_proc *) 492 _kvm_realloc(kd, kd->procbase, size); 493 if (kd->procbase == 0) 494 return (0); 495 st = sysctl(mib, miblen, kd->procbase, &size, NULL, 0); 496 } while (st == -1 && errno == ENOMEM); 497 if (st == -1) { 498 _kvm_syserr(kd, kd->program, "kvm_getprocs"); 499 return (0); 500 } 501 if (size % sizeof(struct kinfo_proc) != 0) { 502 _kvm_err(kd, kd->program, 503 "proc size mismatch (%zd total, %zd chunks)", 504 size, sizeof(struct kinfo_proc)); 505 return (0); 506 } 507 nprocs = size / sizeof(struct kinfo_proc); 508 } else { 509 struct nlist nl[4], *p; 510 511 nl[0].n_name = "_nprocs"; 512 nl[1].n_name = "_procglob"; 513 nl[2].n_name = "_allproc_hsize"; 514 nl[3].n_name = 0; 515 516 if (kvm_nlist(kd, nl) != 0) { 517 for (p = nl; p->n_type != 0; ++p) 518 ; 519 _kvm_err(kd, kd->program, 520 "%s: no such symbol", p->n_name); 521 return (0); 522 } 523 if (KREAD(kd, nl[0].n_value, &nprocs)) { 524 _kvm_err(kd, kd->program, "can't read nprocs"); 525 return (0); 526 } 527 if (KREAD(kd, nl[2].n_value, &allproc_hsize)) { 528 _kvm_err(kd, kd->program, "can't read allproc_hsize"); 529 return (0); 530 } 531 nprocs = kvm_deadprocs(kd, op, arg, allproc_hsize); 532 #ifdef notdef 533 size = nprocs * sizeof(struct kinfo_proc); 534 (void)realloc(kd->procbase, size); 535 #endif 536 } 537 *cnt = nprocs; 538 return (kd->procbase); 539 } 540 541 void 542 _kvm_freeprocs(kvm_t *kd) 543 { 544 if (kd->procbase) { 545 free(kd->procbase); 546 kd->procbase = 0; 547 } 548 } 549 550 void * 551 _kvm_realloc(kvm_t *kd, void *p, size_t n) 552 { 553 void *np = (void *)realloc(p, n); 554 555 if (np == NULL) { 556 free(p); 557 _kvm_err(kd, kd->program, "out of memory"); 558 } 559 return (np); 560 } 561 562 #ifndef MAX 563 #define MAX(a, b) ((a) > (b) ? (a) : (b)) 564 #endif 565 566 /* 567 * Read in an argument vector from the user address space of process pid. 568 * addr if the user-space base address of narg null-terminated contiguous 569 * strings. This is used to read in both the command arguments and 570 * environment strings. Read at most maxcnt characters of strings. 571 */ 572 static char ** 573 kvm_argv(kvm_t *kd, pid_t pid, u_long addr, int narg, int maxcnt) 574 { 575 char *np, *cp, *ep, *ap; 576 u_long oaddr = -1; 577 u_long addr_min = VM_MIN_USER_ADDRESS; 578 u_long addr_max = VM_MAX_USER_ADDRESS; 579 int len, cc; 580 char **argv; 581 582 /* 583 * Check that there aren't an unreasonable number of agruments, 584 * and that the address is in user space. 585 */ 586 if (narg > 512 || addr < addr_min || addr >= addr_max) 587 return (0); 588 589 /* 590 * kd->argv : work space for fetching the strings from the target 591 * process's space, and is converted for returning to caller 592 */ 593 if (kd->argv == 0) { 594 /* 595 * Try to avoid reallocs. 596 */ 597 kd->argc = MAX(narg + 1, 32); 598 kd->argv = (char **)_kvm_malloc(kd, kd->argc * 599 sizeof(*kd->argv)); 600 if (kd->argv == 0) 601 return (0); 602 } else if (narg + 1 > kd->argc) { 603 kd->argc = MAX(2 * kd->argc, narg + 1); 604 kd->argv = (char **)_kvm_realloc(kd, kd->argv, kd->argc * 605 sizeof(*kd->argv)); 606 if (kd->argv == 0) 607 return (0); 608 } 609 /* 610 * kd->argspc : returned to user, this is where the kd->argv 611 * arrays are left pointing to the collected strings. 612 */ 613 if (kd->argspc == 0) { 614 kd->argspc = (char *)_kvm_malloc(kd, PAGE_SIZE); 615 if (kd->argspc == 0) 616 return (0); 617 kd->arglen = PAGE_SIZE; 618 } 619 /* 620 * kd->argbuf : used to pull in pages from the target process. 621 * the strings are copied out of here. 622 */ 623 if (kd->argbuf == 0) { 624 kd->argbuf = (char *)_kvm_malloc(kd, PAGE_SIZE); 625 if (kd->argbuf == 0) 626 return (0); 627 } 628 629 /* Pull in the target process'es argv vector */ 630 cc = sizeof(char *) * narg; 631 if (kvm_uread(kd, pid, addr, (char *)kd->argv, cc) != cc) 632 return (0); 633 /* 634 * ap : saved start address of string we're working on in kd->argspc 635 * np : pointer to next place to write in kd->argspc 636 * len: length of data in kd->argspc 637 * argv: pointer to the argv vector that we are hunting around the 638 * target process space for, and converting to addresses in 639 * our address space (kd->argspc). 640 */ 641 ap = np = kd->argspc; 642 argv = kd->argv; 643 len = 0; 644 /* 645 * Loop over pages, filling in the argument vector. 646 * Note that the argv strings could be pointing *anywhere* in 647 * the user address space and are no longer contiguous. 648 * Note that *argv is modified when we are going to fetch a string 649 * that crosses a page boundary. We copy the next part of the string 650 * into to "np" and eventually convert the pointer. 651 */ 652 while (argv < kd->argv + narg && *argv != NULL) { 653 654 /* get the address that the current argv string is on */ 655 addr = (u_long)*argv & ~(PAGE_SIZE - 1); 656 657 /* is it the same page as the last one? */ 658 if (addr != oaddr) { 659 if (kvm_uread(kd, pid, addr, kd->argbuf, PAGE_SIZE) != 660 PAGE_SIZE) 661 return (0); 662 oaddr = addr; 663 } 664 665 /* offset within the page... kd->argbuf */ 666 addr = (u_long)*argv & (PAGE_SIZE - 1); 667 668 /* cp = start of string, cc = count of chars in this chunk */ 669 cp = kd->argbuf + addr; 670 cc = PAGE_SIZE - addr; 671 672 /* dont get more than asked for by user process */ 673 if (maxcnt > 0 && cc > maxcnt - len) 674 cc = maxcnt - len; 675 676 /* pointer to end of string if we found it in this page */ 677 ep = memchr(cp, '\0', cc); 678 if (ep != NULL) 679 cc = ep - cp + 1; 680 /* 681 * at this point, cc is the count of the chars that we are 682 * going to retrieve this time. we may or may not have found 683 * the end of it. (ep points to the null if the end is known) 684 */ 685 686 /* will we exceed the malloc/realloced buffer? */ 687 if (len + cc > kd->arglen) { 688 size_t off; 689 char **pp; 690 char *op = kd->argspc; 691 692 kd->arglen *= 2; 693 kd->argspc = (char *)_kvm_realloc(kd, kd->argspc, 694 kd->arglen); 695 if (kd->argspc == 0) 696 return (0); 697 /* 698 * Adjust argv pointers in case realloc moved 699 * the string space. 700 */ 701 off = kd->argspc - op; 702 for (pp = kd->argv; pp < argv; pp++) 703 *pp += off; 704 ap += off; 705 np += off; 706 } 707 /* np = where to put the next part of the string in kd->argspc*/ 708 /* np is kinda redundant.. could use "kd->argspc + len" */ 709 memcpy(np, cp, cc); 710 np += cc; /* inc counters */ 711 len += cc; 712 713 /* 714 * if end of string found, set the *argv pointer to the 715 * saved beginning of string, and advance. argv points to 716 * somewhere in kd->argv.. This is initially relative 717 * to the target process, but when we close it off, we set 718 * it to point in our address space. 719 */ 720 if (ep != NULL) { 721 *argv++ = ap; 722 ap = np; 723 } else { 724 /* update the address relative to the target process */ 725 *argv += cc; 726 } 727 728 if (maxcnt > 0 && len >= maxcnt) { 729 /* 730 * We're stopping prematurely. Terminate the 731 * current string. 732 */ 733 if (ep == NULL) { 734 *np = '\0'; 735 *argv++ = ap; 736 } 737 break; 738 } 739 } 740 /* Make sure argv is terminated. */ 741 *argv = NULL; 742 return (kd->argv); 743 } 744 745 static void 746 ps_str_a(struct ps_strings *p, u_long *addr, int *n) 747 { 748 *addr = (u_long)p->ps_argvstr; 749 *n = p->ps_nargvstr; 750 } 751 752 static void 753 ps_str_e(struct ps_strings *p, u_long *addr, int *n) 754 { 755 *addr = (u_long)p->ps_envstr; 756 *n = p->ps_nenvstr; 757 } 758 759 /* 760 * Determine if the proc indicated by p is still active. 761 * This test is not 100% foolproof in theory, but chances of 762 * being wrong are very low. 763 */ 764 static int 765 proc_verify(const struct kinfo_proc *p) 766 { 767 struct kinfo_proc kp; 768 int mib[4]; 769 size_t len; 770 int error; 771 772 mib[0] = CTL_KERN; 773 mib[1] = KERN_PROC; 774 mib[2] = KERN_PROC_PID; 775 mib[3] = p->kp_pid; 776 777 len = sizeof(kp); 778 error = sysctl(mib, 4, &kp, &len, NULL, 0); 779 if (error) 780 return (0); 781 782 error = (p->kp_pid == kp.kp_pid && 783 (kp.kp_stat != SZOMB || p->kp_stat == SZOMB)); 784 return (error); 785 } 786 787 static char ** 788 kvm_doargv(kvm_t *kd, const struct kinfo_proc *kp, int nchr, 789 void (*info)(struct ps_strings *, u_long *, int *)) 790 { 791 char **ap; 792 u_long addr; 793 int cnt; 794 static struct ps_strings arginfo; 795 static u_long ps_strings; 796 size_t len; 797 798 if (ps_strings == 0) { 799 len = sizeof(ps_strings); 800 if (sysctlbyname("kern.ps_strings", &ps_strings, &len, NULL, 801 0) == -1) 802 ps_strings = PS_STRINGS; 803 } 804 805 /* 806 * Pointers are stored at the top of the user stack. 807 */ 808 if (kp->kp_stat == SZOMB || 809 kvm_uread(kd, kp->kp_pid, ps_strings, (char *)&arginfo, 810 sizeof(arginfo)) != sizeof(arginfo)) 811 return (0); 812 813 (*info)(&arginfo, &addr, &cnt); 814 if (cnt == 0) 815 return (0); 816 ap = kvm_argv(kd, kp->kp_pid, addr, cnt, nchr); 817 /* 818 * For live kernels, make sure this process didn't go away. 819 */ 820 if (ap != NULL && (kvm_ishost(kd) || kvm_isvkernel(kd)) && 821 !proc_verify(kp)) 822 ap = NULL; 823 return (ap); 824 } 825 826 /* 827 * Get the command args. This code is now machine independent. 828 */ 829 char ** 830 kvm_getargv(kvm_t *kd, const struct kinfo_proc *kp, int nchr) 831 { 832 int oid[4]; 833 int i; 834 size_t bufsz; 835 static unsigned long buflen; 836 static char *buf, *p; 837 static char **bufp; 838 static int argc; 839 840 if (!kvm_ishost(kd)) { /* XXX: vkernels */ 841 _kvm_err(kd, kd->program, 842 "cannot read user space from dead kernel"); 843 return (0); 844 } 845 846 if (!buflen) { 847 bufsz = sizeof(buflen); 848 i = sysctlbyname("kern.ps_arg_cache_limit", 849 &buflen, &bufsz, NULL, 0); 850 if (i == -1) { 851 buflen = 0; 852 } else { 853 buf = malloc(buflen); 854 if (buf == NULL) 855 buflen = 0; 856 argc = 32; 857 bufp = malloc(sizeof(char *) * argc); 858 } 859 } 860 if (buf != NULL) { 861 oid[0] = CTL_KERN; 862 oid[1] = KERN_PROC; 863 oid[2] = KERN_PROC_ARGS; 864 oid[3] = kp->kp_pid; 865 bufsz = buflen; 866 i = sysctl(oid, 4, buf, &bufsz, 0, 0); 867 if (i == 0 && bufsz > 0) { 868 i = 0; 869 p = buf; 870 do { 871 bufp[i++] = p; 872 p += strlen(p) + 1; 873 if (i >= argc) { 874 argc += argc; 875 bufp = realloc(bufp, 876 sizeof(char *) * argc); 877 } 878 } while (p < buf + bufsz); 879 bufp[i++] = NULL; 880 return (bufp); 881 } 882 } 883 if (kp->kp_flags & P_SYSTEM) 884 return (NULL); 885 return (kvm_doargv(kd, kp, nchr, ps_str_a)); 886 } 887 888 char ** 889 kvm_getenvv(kvm_t *kd, const struct kinfo_proc *kp, int nchr) 890 { 891 return (kvm_doargv(kd, kp, nchr, ps_str_e)); 892 } 893 894 /* 895 * Read from user space. The user context is given by pid. 896 */ 897 ssize_t 898 kvm_uread(kvm_t *kd, pid_t pid, u_long uva, char *buf, size_t len) 899 { 900 char *cp; 901 char procfile[MAXPATHLEN]; 902 ssize_t amount; 903 int fd; 904 905 if (!kvm_ishost(kd)) { /* XXX: vkernels */ 906 _kvm_err(kd, kd->program, 907 "cannot read user space from dead kernel"); 908 return (0); 909 } 910 911 sprintf(procfile, "/proc/%d/mem", pid); 912 fd = open(procfile, O_RDONLY, 0); 913 if (fd < 0) { 914 _kvm_err(kd, kd->program, "cannot open %s", procfile); 915 close(fd); 916 return (0); 917 } 918 919 cp = buf; 920 while (len > 0) { 921 errno = 0; 922 if (lseek(fd, (off_t)uva, 0) == -1 && errno != 0) { 923 _kvm_err(kd, kd->program, "invalid address (%lx) in %s", 924 uva, procfile); 925 break; 926 } 927 amount = read(fd, cp, len); 928 if (amount < 0) { 929 _kvm_syserr(kd, kd->program, "error reading %s", 930 procfile); 931 break; 932 } 933 if (amount == 0) { 934 _kvm_err(kd, kd->program, "EOF reading %s", procfile); 935 break; 936 } 937 cp += amount; 938 uva += amount; 939 len -= amount; 940 } 941 942 close(fd); 943 return ((ssize_t)(cp - buf)); 944 } 945