bsd/kern/kern_ktrace.c

   1 /*
   2  * Copyright (c) 2000-2001 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
  26 /*
  27  * Copyright (c) 1989, 1993
  28  *      The Regents of the University of California.  All rights reserved.
  29  *
  30  * Redistribution and use in source and binary forms, with or without
  31  * modification, are permitted provided that the following conditions
  32  * are met:
  33  * 1. Redistributions of source code must retain the above copyright
  34  *    notice, this list of conditions and the following disclaimer.
  35  * 2. Redistributions in binary form must reproduce the above copyright
  36  *    notice, this list of conditions and the following disclaimer in the
  37  *    documentation and/or other materials provided with the distribution.
  38  * 3. All advertising materials mentioning features or use of this software
  39  *    must display the following acknowledgement:
  40  *      This product includes software developed by the University of
  41  *      California, Berkeley and its contributors.
  42  * 4. Neither the name of the University nor the names of its contributors
  43  *    may be used to endorse or promote products derived from this software
  44  *    without specific prior written permission.
  45  *
  46  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  47  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  48  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  49  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  50  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  51  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  52  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  53  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  54  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  55  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  56  * SUCH DAMAGE.
  57  *
  58  *      @(#)kern_ktrace.c       8.2 (Berkeley) 9/23/93
  59  * $FreeBSD: src/sys/kern/kern_ktrace.c,v 1.35.2.4 2001/03/05 13:09:01 obrien Exp $
  60  */
  61
  62
  63 #include <sys/param.h>
  64 #include <sys/systm.h>
  65 #include <sys/types.h>
  66 #include <sys/proc.h>
  67 #include <sys/file.h>
  68 #include <sys/namei.h>
  69 #include <sys/vnode.h>
  70 #if KTRACE
  71 #include <sys/ktrace.h>
  72 #endif
  73 #include <sys/malloc.h>
  74 #include <sys/syslog.h>
  75
  76 #if KTRACE
  77 static struct ktr_header *ktrgetheader __P((int type));
  78 static void ktrwrite __P((struct vnode *, struct ktr_header *,
  79         struct uio *, int));
  80 static int ktrcanset __P((struct proc *,struct proc *));
  81 static int ktrsetchildren __P((struct proc *,struct proc *,
  82         int, int, struct vnode *));
  83 static int ktrops __P((struct proc *,struct proc *,int,int,struct vnode *));
  84
  85
  86 static struct ktr_header *
  87 ktrgetheader(type)
  88         int type;
  89 {
  90         register struct ktr_header *kth;
  91         struct proc *p = current_proc();        /* XXX */
  92
  93         MALLOC(kth, struct ktr_header *, sizeof (struct ktr_header),
  94                 M_KTRACE, M_WAITOK);
  95         kth->ktr_type = type;
  96         microtime(&kth->ktr_time);
  97         kth->ktr_pid = p->p_pid;
  98         bcopy(p->p_comm, kth->ktr_comm, MAXCOMLEN);
  99         return (kth);
 100 }
 101 #endif
 102
 103 void
 104 ktrsyscall(p, code, narg, args, funnel_type)
 105         struct proc *p;
 106         int code, narg;
 107         register_t args[];
 108         int funnel_type;
 109 {
 110 #if KTRACE
 111         struct vnode *vp;
 112         struct  ktr_header *kth;
 113         struct  ktr_syscall *ktp;
 114         register int len;
 115         register_t *argp;
 116         int i;
 117
 118         if (!KTRPOINT(p, KTR_SYSCALL))
 119                 return;
 120
 121         vp = p->p_tracep;
 122         len = __offsetof(struct ktr_syscall, ktr_args) +
 123             (narg * sizeof(register_t));
 124         p->p_traceflag |= KTRFAC_ACTIVE;
 125         kth = ktrgetheader(KTR_SYSCALL);
 126         MALLOC(ktp, struct ktr_syscall *, len, M_KTRACE, M_WAITOK);
 127         ktp->ktr_code = code;
 128         ktp->ktr_narg = narg;
 129         argp = &ktp->ktr_args[0];
 130         for (i = 0; i < narg; i++)
 131                 *argp++ = args[i];
 132         kth->ktr_buf = (caddr_t)ktp;
 133         kth->ktr_len = len;
 134         ktrwrite(vp, kth, NULL, funnel_type);
 135         FREE(ktp, M_KTRACE);
 136         FREE(kth, M_KTRACE);
 137         p->p_traceflag &= ~KTRFAC_ACTIVE;
 138 #else
 139         return;
 140 #endif
 141 }
 142
 143 void
 144 ktrsysret(p, code, error, retval, funnel_type)
 145         struct proc *p;
 146         int code, error;
 147         register_t retval;
 148         int funnel_type;
 149 {
 150 #if KTRACE
 151         struct vnode *vp;
 152         struct ktr_header *kth;
 153         struct ktr_sysret ktp;
 154
 155         if (!KTRPOINT(p, KTR_SYSRET))
 156                 return;
 157
 158         vp = p->p_tracep;
 159         p->p_traceflag |= KTRFAC_ACTIVE;
 160         kth = ktrgetheader(KTR_SYSRET);
 161         ktp.ktr_code = code;
 162         ktp.ktr_error = error;
 163         ktp.ktr_retval = retval;                /* what about val2 ? */
 164
 165         kth->ktr_buf = (caddr_t)&ktp;
 166         kth->ktr_len = sizeof(struct ktr_sysret);
 167
 168         ktrwrite(vp, kth, NULL, funnel_type);
 169         FREE(kth, M_KTRACE);
 170         p->p_traceflag &= ~KTRFAC_ACTIVE;
 171 #else
 172         return;
 173 #endif
 174 }
 175
 176 #if KTRACE
 177 void
 178 ktrnamei(vp, path)
 179         struct vnode *vp;
 180         char *path;
 181 {
 182         struct ktr_header *kth;
 183         struct proc *p = current_proc();        /* XXX */
 184
 185         p->p_traceflag |= KTRFAC_ACTIVE;
 186         kth = ktrgetheader(KTR_NAMEI);
 187         kth->ktr_len = strlen(path);
 188         kth->ktr_buf = path;
 189
 190         ktrwrite(vp, kth, NULL, KERNEL_FUNNEL);
 191         FREE(kth, M_KTRACE);
 192         p->p_traceflag &= ~KTRFAC_ACTIVE;
 193 }
 194
 195 void
 196 ktrgenio(vp, fd, rw, uio, error, funnel_type)
 197         struct vnode *vp;
 198         int fd;
 199         enum uio_rw rw;
 200         struct uio *uio;
 201         int error;
 202         int funnel_type;
 203 {
 204         struct ktr_header *kth;
 205         struct ktr_genio ktg;
 206         struct proc *p = current_proc();        /* XXX */
 207
 208         if (error)
 209                 return;
 210
 211         p->p_traceflag |= KTRFAC_ACTIVE;
 212         kth = ktrgetheader(KTR_GENIO);
 213         ktg.ktr_fd = fd;
 214         ktg.ktr_rw = rw;
 215         kth->ktr_buf = (caddr_t)&ktg;
 216         kth->ktr_len = sizeof(struct ktr_genio);
 217         uio->uio_offset = 0;
 218         uio->uio_rw = UIO_WRITE;
 219
 220         ktrwrite(vp, kth, uio, funnel_type);
 221         FREE(kth, M_KTRACE);
 222         p->p_traceflag &= ~KTRFAC_ACTIVE;
 223 }
 224
 225 void
 226 ktrpsig(vp, sig, action, mask, code, funnel_type)
 227         struct vnode *vp;
 228         int sig;
 229         sig_t action;
 230         sigset_t *mask;
 231         int code;
 232         int funnel_type;
 233 {
 234         struct ktr_header *kth;
 235         struct ktr_psig kp;
 236         struct proc *p = current_proc();        /* XXX */
 237
 238         p->p_traceflag |= KTRFAC_ACTIVE;
 239         kth = ktrgetheader(KTR_PSIG);
 240         kp.signo = (char)sig;
 241         kp.action = action;
 242         kp.mask = *mask;
 243         kp.code = code;
 244         kth->ktr_buf = (caddr_t)&kp;
 245         kth->ktr_len = sizeof (struct ktr_psig);
 246
 247         ktrwrite(vp, kth, NULL, funnel_type);
 248         FREE(kth, M_KTRACE);
 249         p->p_traceflag &= ~KTRFAC_ACTIVE;
 250 }
 251
 252 void
 253 ktrcsw(vp, out, user, funnel_type)
 254         struct vnode *vp;
 255         int out, user;
 256         int funnel_type;
 257 {
 258         struct ktr_header *kth;
 259         struct  ktr_csw kc;
 260         struct proc *p = current_proc();        /* XXX */
 261
 262         p->p_traceflag |= KTRFAC_ACTIVE;
 263         kth = ktrgetheader(KTR_CSW);
 264         kc.out = out;
 265         kc.user = user;
 266         kth->ktr_buf = (caddr_t)&kc;
 267         kth->ktr_len = sizeof (struct ktr_csw);
 268
 269         ktrwrite(vp, kth, NULL, funnel_type);
 270         FREE(kth, M_KTRACE);
 271         p->p_traceflag &= ~KTRFAC_ACTIVE;
 272 }
 273 #endif /* KTRACE */
 274
 275 /* Interface and common routines */
 276
 277 /*
 278  * ktrace system call
 279  */
 280 struct ktrace_args {
 281         char    *fname;
 282         int     ops;
 283         int     facs;
 284         int     pid;
 285 };
 286 /* ARGSUSED */
 287 int
 288 ktrace(curp, uap, retval)
 289         struct proc *curp;
 290         register struct ktrace_args *uap;
 291         register_t *retval;
 292 {
 293 #if KTRACE
 294         register struct vnode *vp = NULL;
 295         register struct proc *p;
 296         struct pgrp *pg;
 297         int facs = uap->facs & ~KTRFAC_ROOT;
 298         int ops = KTROP(uap->ops);
 299         int descend = uap->ops & KTRFLAG_DESCEND;
 300         int ret = 0;
 301         int error = 0;
 302         struct nameidata nd;
 303
 304         curp->p_traceflag |= KTRFAC_ACTIVE;
 305         if (ops != KTROP_CLEAR) {
 306                 /*
 307                  * an operation which requires a file argument.
 308                  */
 309                 NDINIT(&nd, LOOKUP, (NOFOLLOW|LOCKLEAF), UIO_USERSPACE, uap->fname, curp);
 310                 error = vn_open(&nd, FREAD|FWRITE|O_NOFOLLOW, 0);
 311                 if (error) {
 312                         curp->p_traceflag &= ~KTRFAC_ACTIVE;
 313                         return (error);
 314                 }
 315                 vp = nd.ni_vp;
 316                 VOP_UNLOCK(vp, 0, curp);
 317                 if (vp->v_type != VREG) {
 318                         (void) vn_close(vp, FREAD|FWRITE, curp->p_ucred, curp);
 319                         curp->p_traceflag &= ~KTRFAC_ACTIVE;
 320                         return (EACCES);
 321                 }
 322         }
 323         /*
 324          * Clear all uses of the tracefile
 325          */
 326         if (ops == KTROP_CLEARFILE) {
 327                 LIST_FOREACH(p, &allproc, p_list) {
 328                         if (p->p_tracep == vp) {
 329                                 if (ktrcanset(curp, p)) {
 330                                         struct vnode *tvp = p->p_tracep;
 331                                         /* no more tracing */
 332                                         p->p_traceflag = 0;
 333                                         if (tvp != NULL) {
 334                                                 p->p_tracep = NULL;
 335                                                 vrele(tvp);
 336                                         }
 337                                 } else
 338                                         error = EPERM;
 339                         }
 340                 }
 341                 goto done;
 342         }
 343
 344         /*
 345          * need something to (un)trace (XXX - why is this here?)
 346          */
 347         if (!facs) {
 348                 error = EINVAL;
 349                 goto done;
 350         }
 351         /*
 352          * do it
 353          */
 354         if (uap->pid < 0) {
 355                 /*
 356                  * by process group
 357                  */
 358                 pg = pgfind(-uap->pid);
 359                 if (pg == NULL) {
 360                         error = ESRCH;
 361                         goto done;
 362                 }
 363                 LIST_FOREACH(p, &pg->pg_members, p_pglist)
 364                         if (descend)
 365                                 ret |= ktrsetchildren(curp, p, ops, facs, vp);
 366                         else
 367                                 ret |= ktrops(curp, p, ops, facs, vp);
 368
 369         } else {
 370                 /*
 371                  * by pid
 372                  */
 373                 p = pfind(uap->pid);
 374                 if (p == NULL) {
 375                         error = ESRCH;
 376                         goto done;
 377                 }
 378                 if (descend)
 379                         ret |= ktrsetchildren(curp, p, ops, facs, vp);
 380                 else
 381                         ret |= ktrops(curp, p, ops, facs, vp);
 382         }
 383         if (!ret)
 384                 error = EPERM;
 385 done:
 386         if (vp != NULL)
 387                 (void) vn_close(vp, FWRITE, curp->p_ucred, curp);
 388         curp->p_traceflag &= ~KTRFAC_ACTIVE;
 389         return (error);
 390 #else
 391         return ENOSYS;
 392 #endif
 393 }
 394
 395 /*
 396  * utrace system call
 397  */
 398 struct  utrace_args {
 399         const void *    addr;
 400         size_t  len;
 401 };
 402
 403 /* ARGSUSED */
 404 int
 405 utrace(curp, uap, retval)
 406         struct proc *curp;
 407         register struct utrace_args *uap;
 408         register_t *retval;
 409 {
 410 #if KTRACE
 411         struct ktr_header *kth;
 412         struct proc *p = current_proc();        /* XXX */
 413         register caddr_t cp;
 414
 415         if (!KTRPOINT(p, KTR_USER))
 416                 return (0);
 417         if (uap->len > KTR_USER_MAXLEN)
 418                 return (EINVAL);
 419         p->p_traceflag |= KTRFAC_ACTIVE;
 420         kth = ktrgetheader(KTR_USER);
 421         MALLOC(cp, caddr_t, uap->len, M_KTRACE, M_WAITOK);
 422         if (!copyin(uap->addr, cp, uap->len)) {
 423                 kth->ktr_buf = cp;
 424                 kth->ktr_len = uap->len;
 425                 ktrwrite(p->p_tracep, kth, NULL, KERNEL_FUNNEL);
 426         }
 427         FREE(kth, M_KTRACE);
 428         FREE(cp, M_KTRACE);
 429         p->p_traceflag &= ~KTRFAC_ACTIVE;
 430
 431         return (0);
 432 #else
 433         return (ENOSYS);
 434 #endif
 435 }
 436
 437 #if KTRACE
 438 static int
 439 ktrops(curp, p, ops, facs, vp)
 440         struct proc *p, *curp;
 441         int ops, facs;
 442         struct vnode *vp;
 443 {
 444         struct vnode *tvp;
 445
 446         if (!ktrcanset(curp, p))
 447                 return (0);
 448         if (ops == KTROP_SET) {
 449                 if (p->p_tracep != vp) {
 450                         /*
 451                          * if trace file already in use, relinquish
 452                          */
 453                         tvp = p->p_tracep;
 454                         VREF(vp);
 455                         p->p_tracep = vp;
 456                         if (tvp != NULL)
 457                                 vrele(tvp);
 458                 }
 459                 p->p_traceflag |= facs;
 460                 if (curp->p_ucred->cr_uid == 0)
 461                         p->p_traceflag |= KTRFAC_ROOT;
 462         } else {
 463                 /* KTROP_CLEAR */
 464                 if (((p->p_traceflag &= ~facs) & KTRFAC_MASK) == 0) {
 465                         /* no more tracing */
 466                         tvp = p->p_tracep;
 467                         p->p_traceflag = 0;
 468                         if (tvp != NULL) {
 469                                 p->p_tracep = NULL;
 470                                 vrele(tvp);
 471                         }
 472                 }
 473         }
 474
 475         return (1);
 476 }
 477
 478 static int
 479 ktrsetchildren(curp, top, ops, facs, vp)
 480         struct proc *curp, *top;
 481         int ops, facs;
 482         struct vnode *vp;
 483 {
 484         register struct proc *p;
 485         register int ret = 0;
 486
 487         p = top;
 488         for (;;) {
 489                 ret |= ktrops(curp, p, ops, facs, vp);
 490                 /*
 491                  * If this process has children, descend to them next,
 492                  * otherwise do any siblings, and if done with this level,
 493                  * follow back up the tree (but not past top).
 494                  */
 495                 if (!LIST_EMPTY(&p->p_children))
 496                         p = LIST_FIRST(&p->p_children);
 497                 else for (;;) {
 498                         if (p == top)
 499                                 return (ret);
 500                         if (LIST_NEXT(p, p_sibling)) {
 501                                 p = LIST_NEXT(p, p_sibling);
 502                                 break;
 503                         }
 504                         p = p->p_pptr;
 505                 }
 506         }
 507         /*NOTREACHED*/
 508 }
 509
 510 static void
 511 ktrwrite(vp, kth, uio, funnel_type)
 512         struct vnode *vp;
 513         register struct ktr_header *kth;
 514         struct uio *uio;
 515 {
 516         struct uio auio;
 517         struct iovec aiov[2];
 518         register struct proc *p = current_proc();       /* XXX */
 519         int error;
 520
 521         if (vp == NULL)
 522                 return;
 523
 524         if (funnel_type == -1) {
 525                 funnel_t *f = thread_funnel_get();
 526                 if(f == THR_FUNNEL_NULL)
 527                         funnel_type = NO_FUNNEL;
 528                 else if (f == (funnel_t *)network_flock)
 529                         funnel_type = NETWORK_FUNNEL;
 530                 else if (f == (funnel_t *)kernel_flock)
 531                         funnel_type = KERNEL_FUNNEL;
 532         }
 533
 534         switch (funnel_type) {
 535         case KERNEL_FUNNEL:
 536                 /* Nothing more to do */
 537                 break;
 538         case NETWORK_FUNNEL:
 539                 thread_funnel_switch(NETWORK_FUNNEL, KERNEL_FUNNEL);
 540                 break;
 541         case NO_FUNNEL:
 542                 (void) thread_funnel_set(kernel_flock, TRUE);
 543                 break;
 544         default:
 545                 panic("Invalid funnel (%)", funnel_type);
 546         }
 547         auio.uio_iov = &aiov[0];
 548         auio.uio_offset = 0;
 549         auio.uio_segflg = UIO_SYSSPACE;
 550         auio.uio_rw = UIO_WRITE;
 551         aiov[0].iov_base = (caddr_t)kth;
 552         aiov[0].iov_len = sizeof(struct ktr_header);
 553         auio.uio_resid = sizeof(struct ktr_header);
 554         auio.uio_iovcnt = 1;
 555         auio.uio_procp = current_proc();
 556         if (kth->ktr_len > 0) {
 557                 auio.uio_iovcnt++;
 558                 aiov[1].iov_base = kth->ktr_buf;
 559                 aiov[1].iov_len = kth->ktr_len;
 560                 auio.uio_resid += kth->ktr_len;
 561                 if (uio != NULL)
 562                         kth->ktr_len += uio->uio_resid;
 563         }
 564         error = vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
 565         if (error)
 566                 goto bad;
 567         (void)VOP_LEASE(vp, p, p->p_ucred, LEASE_WRITE);
 568         error = VOP_WRITE(vp, &auio, IO_UNIT | IO_APPEND, p->p_ucred);
 569         if (error == 0 && uio != NULL) {
 570                 (void)VOP_LEASE(vp, p, p->p_ucred, LEASE_WRITE);
 571                 error = VOP_WRITE(vp, uio, IO_UNIT | IO_APPEND, p->p_ucred);
 572         }
 573         VOP_UNLOCK(vp, 0, p);
 574         if (!error) {
 575                 switch (funnel_type) {
 576                 case KERNEL_FUNNEL:
 577                         /* Nothing more to do */
 578                         break;
 579                 case NETWORK_FUNNEL:
 580                         thread_funnel_switch(KERNEL_FUNNEL, NETWORK_FUNNEL);
 581                         /* switch funnel to NETWORK_FUNNEL */
 582                         break;
 583                 case NO_FUNNEL:
 584                          (void) thread_funnel_set(kernel_flock, FALSE);
 585                         break;
 586                 default:
 587                         panic("Invalid funnel (%)", funnel_type);
 588                 }
 589                 return;
 590         }
 591
 592 bad:
 593         /*
 594          * If error encountered, give up tracing on this vnode.
 595          */
 596         log(LOG_NOTICE, "ktrace write failed, errno %d, tracing stopped\n",
 597             error);
 598         LIST_FOREACH(p, &allproc, p_list) {
 599                 if (p->p_tracep == vp) {
 600                         p->p_tracep = NULL;
 601                         p->p_traceflag = 0;
 602                         vrele(vp);
 603                 }
 604         }
 605
 606         switch (funnel_type) {
 607         case KERNEL_FUNNEL:
 608                 /* Nothing more to do */
 609                 break;
 610         case NETWORK_FUNNEL:
 611                 thread_funnel_switch(KERNEL_FUNNEL, NETWORK_FUNNEL);
 612                 /* switch funnel to NETWORK_FUNNEL */
 613                 break;
 614         case NO_FUNNEL:
 615                  (void) thread_funnel_set(kernel_flock, FALSE);
 616                 break;
 617         default:
 618                 panic("Invalid funnel (%)", funnel_type);
 619         }
 620 }
 621
 622 /*
 623  * Return true if caller has permission to set the ktracing state
 624  * of target.  Essentially, the target can't possess any
 625  * more permissions than the caller.  KTRFAC_ROOT signifies that
 626  * root previously set the tracing status on the target process, and
 627  * so, only root may further change it.
 628  *
 629  * TODO: check groups.  use caller effective gid.
 630  */
 631 static int
 632 ktrcanset(callp, targetp)
 633         struct proc *callp, *targetp;
 634 {
 635         register struct pcred *caller = callp->p_cred;
 636         register struct pcred *target = targetp->p_cred;
 637
 638         if (!PRISON_CHECK(callp, targetp))
 639                 return (0);
 640         if ((caller->pc_ucred->cr_uid == target->p_ruid &&
 641              target->p_ruid == target->p_svuid &&
 642              caller->p_rgid == target->p_rgid &&        /* XXX */
 643              target->p_rgid == target->p_svgid &&
 644              (targetp->p_traceflag & KTRFAC_ROOT) == 0) ||
 645              caller->pc_ucred->cr_uid == 0)
 646                 return (1);
 647
 648         return (0);
 649 }
 650
 651 #endif /* KTRACE */