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