[unix-history] / sys / kern / kern_ktrace.c

/*
 * Copyright (c) 1989 The Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	from: @(#)kern_ktrace.c	7.15 (Berkeley) 6/21/91
 *	$Id: kern_ktrace.c,v 1.5 1993/11/25 01:33:00 wollman Exp $
 */

#ifdef KTRACE

#include "param.h"
#include "systm.h"
#include "proc.h"
#include "file.h"
#include "namei.h"
#include "vnode.h"
#include "ktrace.h"
#include "malloc.h"
#include "syslog.h"

static void ktrwrite(struct vnode *, struct ktr_header *);
static int ktrops(struct proc *, struct proc *, int, int, struct vnode *);
static int ktrsetchildren(struct proc *, struct proc *, int, int, struct vnode *);
static int ktrcanset(struct proc *, struct proc *);

static struct ktr_header *
ktrgetheader(type)
	int type;
{
	register struct ktr_header *kth;
	struct proc *p = curproc;	/* XXX */

	MALLOC(kth, struct ktr_header *, sizeof (struct ktr_header), 
		M_TEMP, M_WAITOK);
	kth->ktr_type = type;
	microtime(&kth->ktr_time);
	kth->ktr_pid = p->p_pid;
	bcopy(p->p_comm, kth->ktr_comm, MAXCOMLEN);
	return (kth);
}

void
ktrsyscall(vp, code, narg, args)
	struct vnode *vp;
	int code, narg, args[];
{
	struct	ktr_header *kth = ktrgetheader(KTR_SYSCALL);
	struct	ktr_syscall *ktp;
	register len = sizeof(struct ktr_syscall) + (narg * sizeof(int));
	int 	*argp, i;

	MALLOC(ktp, struct ktr_syscall *, len, M_TEMP, M_WAITOK);
	ktp->ktr_code = code;
	ktp->ktr_narg = narg;
	argp = (int *)((char *)ktp + sizeof(struct ktr_syscall));
	for (i = 0; i < narg; i++)
		*argp++ = args[i];
	kth->ktr_buf = (caddr_t)ktp;
	kth->ktr_len = len;
	ktrwrite(vp, kth);
	FREE(ktp, M_TEMP);
	FREE(kth, M_TEMP);
}

void
ktrsysret(vp, code, error, retval)
	struct vnode *vp;
	int code, error, retval;
{
	struct ktr_header *kth = ktrgetheader(KTR_SYSRET);
	struct ktr_sysret ktp;

	ktp.ktr_code = code;
	ktp.ktr_error = error;
	ktp.ktr_retval = retval;		/* what about val2 ? */

	kth->ktr_buf = (caddr_t)&ktp;
	kth->ktr_len = sizeof(struct ktr_sysret);

	ktrwrite(vp, kth);
	FREE(kth, M_TEMP);
}

void
ktrnamei(vp, path)
	struct vnode *vp;
	char *path;
{
	struct ktr_header *kth = ktrgetheader(KTR_NAMEI);

	kth->ktr_len = strlen(path);
	kth->ktr_buf = path;

	ktrwrite(vp, kth);
	FREE(kth, M_TEMP);
}

void
ktrgenio(vp, fd, rw, iov, len, error)
	struct vnode *vp;
	int fd;
	enum uio_rw rw;
	register struct iovec *iov;
	int len;
	int error;
{
	struct ktr_header *kth = ktrgetheader(KTR_GENIO);
	register struct ktr_genio *ktp;
	register caddr_t cp;
	register int resid = len, cnt;
	
	if (error)
		return;
	MALLOC(ktp, struct ktr_genio *, sizeof(struct ktr_genio) + len,
		M_TEMP, M_WAITOK);
	ktp->ktr_fd = fd;
	ktp->ktr_rw = rw;
	cp = (caddr_t)((char *)ktp + sizeof (struct ktr_genio));
	while (resid > 0) {
		if ((cnt = iov->iov_len) > resid)
			cnt = resid;
		if (copyin(iov->iov_base, cp, (unsigned)cnt))
			goto done;
		cp += cnt;
		resid -= cnt;
		iov++;
	}
	kth->ktr_buf = (caddr_t)ktp;
	kth->ktr_len = sizeof (struct ktr_genio) + len;

	ktrwrite(vp, kth);
done:
	FREE(kth, M_TEMP);
	FREE(ktp, M_TEMP);
}

void
ktrpsig(vp, sig, action, mask, code)
	struct	vnode *vp;
	int sig;
	sig_t	action;
	int mask;
	int code;
{
	struct ktr_header *kth = ktrgetheader(KTR_PSIG);
	struct ktr_psig	kp;

	kp.signo = (char)sig;
	kp.action = action;
	kp.mask = mask;
	kp.code = code;
	kth->ktr_buf = (caddr_t)&kp;
	kth->ktr_len = sizeof (struct ktr_psig);

	ktrwrite(vp, kth);
	FREE(kth, M_TEMP);
}

/* Interface and common routines */

/*
 * ktrace system call
 */

struct ktrace_args {
	char	*fname;
	int	ops;
	int	facs;
	int	pid;
};

/* ARGSUSED */
int
ktrace(curp, uap, retval)
	struct proc *curp;
	register struct ktrace_args *uap;
	int *retval;
{
	register struct vnode *vp = NULL;
	register struct proc *p;
	struct pgrp *pg;
	int facs = uap->facs & ~KTRFAC_ROOT;
	int ops = KTROP(uap->ops);
	int descend = uap->ops & KTRFLAG_DESCEND;
	int ret = 0;
	int error = 0;
	struct nameidata nd;

	if (ops != KTROP_CLEAR) {
		/*
		 * an operation which requires a file argument.
		 */
		nd.ni_segflg = UIO_USERSPACE;
		nd.ni_dirp = uap->fname;
		if (error = vn_open(&nd, curp, FREAD|FWRITE, 0))
			return (error);
		vp = nd.ni_vp;
		VOP_UNLOCK(vp);
		if (vp->v_type != VREG) {
			(void) vn_close(vp, FREAD|FWRITE, curp->p_ucred, curp);
			return (EACCES);
		}
	}
	/*
	 * Clear all uses of the tracefile
	 */
	if (ops == KTROP_CLEARFILE) {
		for (p = allproc; p != NULL; p = p->p_nxt) {
			if (p->p_tracep == vp) {
				if (ktrcanset(curp, p)) {
					p->p_tracep = NULL;
					p->p_traceflag = 0;
					(void) vn_close(vp, FREAD|FWRITE,
						p->p_ucred, p);
				} else
					error = EPERM;
			}
		}
		goto done;
	}
	/*
	 * need something to (un)trace (XXX - why is this here?)
	 */
	if (!facs) {
		error = EINVAL;
		goto done;
	}
	/* 
	 * do it
	 */
	if (uap->pid < 0) {
		/*
		 * by process group
		 */
		pg = pgfind(-uap->pid);
		if (pg == NULL) {
			error = ESRCH;
			goto done;
		}
		for (p = pg->pg_mem; p != NULL; p = p->p_pgrpnxt)
			if (descend)
				ret |= ktrsetchildren(curp, p, ops, facs, vp);
			else 
				ret |= ktrops(curp, p, ops, facs, vp);
					
	} else {
		/*
		 * by pid
		 */
		p = pfind(uap->pid);
		if (p == NULL) {
			error = ESRCH;
			goto done;
		}
		if (descend)
			ret |= ktrsetchildren(curp, p, ops, facs, vp);
		else
			ret |= ktrops(curp, p, ops, facs, vp);
	}
	if (!ret)
		error = EPERM;
done:
	if (vp != NULL)
		(void) vn_close(vp, FWRITE, curp->p_ucred, curp);
	return (error);
}

static int
ktrops(curp, p, ops, facs, vp)
	struct proc *curp, *p;
	int ops;
	int facs;
	struct vnode *vp;
{

	if (!ktrcanset(curp, p))
		return (0);
	if (ops == KTROP_SET) {
		if (p->p_tracep != vp) { 
			/*
			 * if trace file already in use, relinquish
			 */
			if (p->p_tracep != NULL)
				vrele(p->p_tracep);
			VREF(vp);
			p->p_tracep = vp;
		}
		p->p_traceflag |= facs;
		if (curp->p_ucred->cr_uid == 0)
			p->p_traceflag |= KTRFAC_ROOT;
	} else {	
		/* KTROP_CLEAR */
		if (((p->p_traceflag &= ~facs) & KTRFAC_MASK) == 0) {
			/* no more tracing */
			p->p_traceflag = 0;
			if (p->p_tracep != NULL) {
				vrele(p->p_tracep);
				p->p_tracep = NULL;
			}
		}
	}

	return (1);
}

static int
ktrsetchildren(curp, top, ops, facs, vp)
	struct proc *curp, *top;
	int ops;
	int facs;
	struct vnode *vp;
{
	register struct proc *p;
	register int ret = 0;

	p = top;
	for (;;) {
		ret |= ktrops(curp, p, ops, facs, vp);
		/*
		 * If this process has children, descend to them next,
		 * otherwise do any siblings, and if done with this level,
		 * follow back up the tree (but not past top).
		 */
		if (p->p_cptr)
			p = p->p_cptr;
		else if (p == top)
			return (ret);
		else if (p->p_osptr)
			p = p->p_osptr;
		else for (;;) {
			p = p->p_pptr;
			if (p == top)
				return (ret);
			if (p->p_osptr) {
				p = p->p_osptr;
				break;
			}
		}
	}
	/*NOTREACHED*/
}

static void
ktrwrite(vp, kth)
	struct vnode *vp;
	register struct ktr_header *kth;
{
	struct uio auio;
	struct iovec aiov[2];
	register struct proc *p = curproc;	/* XXX */
	int error;

	if (vp == NULL)
		return;
	auio.uio_iov = &aiov[0];
	auio.uio_offset = 0;
	auio.uio_segflg = UIO_SYSSPACE;
	auio.uio_rw = UIO_WRITE;
	aiov[0].iov_base = (caddr_t)kth;
	aiov[0].iov_len = sizeof(struct ktr_header);
	auio.uio_resid = sizeof(struct ktr_header);
	auio.uio_iovcnt = 1;
	auio.uio_procp = (struct proc *)0;
	if (kth->ktr_len > 0) {
		auio.uio_iovcnt++;
		aiov[1].iov_base = kth->ktr_buf;
		aiov[1].iov_len = kth->ktr_len;
		auio.uio_resid += kth->ktr_len;
	}
	VOP_LOCK(vp);
	error = VOP_WRITE(vp, &auio, IO_UNIT|IO_APPEND, p->p_ucred);
	VOP_UNLOCK(vp);
	if (!error)
		return;
	/*
	 * If error encountered, give up tracing on this vnode.
	 */
	log(LOG_NOTICE, "ktrace write failed, errno %d, tracing stopped\n",
	    error);
	for (p = allproc; p != NULL; p = p->p_nxt) {
		if (p->p_tracep == vp) {
			p->p_tracep = NULL;
			p->p_traceflag = 0;
			vrele(vp);
		}
	}
}

/*
 * Return true if caller has permission to set the ktracing state
 * of target.  Essentially, the target can't possess any
 * more permissions than the caller.  KTRFAC_ROOT signifies that
 * root previously set the tracing status on the target process, and 
 * so, only root may further change it.
 *
 * TODO: check groups.  use caller effective gid.
 */
static int
ktrcanset(callp, targetp)
	struct proc *callp, *targetp;
{
	register struct pcred *caller = callp->p_cred;
	register struct pcred *target = targetp->p_cred;

	if ((caller->pc_ucred->cr_uid == target->p_ruid &&
	     target->p_ruid == target->p_svuid &&
	     caller->p_rgid == target->p_rgid &&	/* XXX */
	     target->p_rgid == target->p_svgid &&
	     (targetp->p_traceflag & KTRFAC_ROOT) == 0) ||
	     caller->pc_ucred->cr_uid == 0)
		return (1);

	return (0);
}

#endif
Commit	Line	Data
15637ed4 RG	1	/*
	2	* Copyright (c) 1989 The Regents of the University of California.
	3	* All rights reserved.
	4	*
	5	* Redistribution and use in source and binary forms, with or without
	6	* modification, are permitted provided that the following conditions
	7	* are met:
	8	* 1. Redistributions of source code must retain the above copyright
	9	* notice, this list of conditions and the following disclaimer.
	10	* 2. Redistributions in binary form must reproduce the above copyright
	11	* notice, this list of conditions and the following disclaimer in the
	12	* documentation and/or other materials provided with the distribution.
	13	* 3. All advertising materials mentioning features or use of this software
	14	* must display the following acknowledgement:
	15	* This product includes software developed by the University of
	16	* California, Berkeley and its contributors.
	17	* 4. 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	*
600f7f07	33	* from: @(#)kern_ktrace.c 7.15 (Berkeley) 6/21/91
fde1aeb2	34	* $Id: kern_ktrace.c,v 1.5 1993/11/25 01:33:00 wollman Exp $
15637ed4 RG	35	*/
	36
	37	#ifdef KTRACE
	38
	39	#include "param.h"
dd18dc33	40	#include "systm.h"
15637ed4 RG	41	#include "proc.h"
	42	#include "file.h"
	43	#include "namei.h"
	44	#include "vnode.h"
	45	#include "ktrace.h"
	46	#include "malloc.h"
	47	#include "syslog.h"
	48
4c45483e	49	static void ktrwrite(struct vnode , struct ktr_header );
fde1aeb2 GW	50	static int ktrops(struct proc , struct proc , int, int, struct vnode *);
	51	static int ktrsetchildren(struct proc , struct proc , int, int, struct vnode *);
	52	static int ktrcanset(struct proc , struct proc );
4c45483e	53
fde1aeb2	54	static struct ktr_header *
15637ed4	55	ktrgetheader(type)
4c45483e	56	int type;
15637ed4 RG	57	{
	58	register struct ktr_header *kth;
	59	struct proc p = curproc; / XXX */
	60
	61	MALLOC(kth, struct ktr_header *, sizeof (struct ktr_header),
	62	M_TEMP, M_WAITOK);
	63	kth->ktr_type = type;
	64	microtime(&kth->ktr_time);
	65	kth->ktr_pid = p->p_pid;
	66	bcopy(p->p_comm, kth->ktr_comm, MAXCOMLEN);
	67	return (kth);
	68	}
	69
4c45483e	70	void
15637ed4 RG	71	ktrsyscall(vp, code, narg, args)
	72	struct vnode *vp;
	73	int code, narg, args[];
	74	{
	75	struct ktr_header *kth = ktrgetheader(KTR_SYSCALL);
	76	struct ktr_syscall *ktp;
	77	register len = sizeof(struct ktr_syscall) + (narg * sizeof(int));
	78	int *argp, i;
	79
	80	MALLOC(ktp, struct ktr_syscall *, len, M_TEMP, M_WAITOK);
	81	ktp->ktr_code = code;
	82	ktp->ktr_narg = narg;
	83	argp = (int )((char )ktp + sizeof(struct ktr_syscall));
	84	for (i = 0; i < narg; i++)
	85	*argp++ = args[i];
	86	kth->ktr_buf = (caddr_t)ktp;
	87	kth->ktr_len = len;
	88	ktrwrite(vp, kth);
	89	FREE(ktp, M_TEMP);
	90	FREE(kth, M_TEMP);
	91	}
	92
4c45483e	93	void
15637ed4 RG	94	ktrsysret(vp, code, error, retval)
	95	struct vnode *vp;
	96	int code, error, retval;
	97	{
	98	struct ktr_header *kth = ktrgetheader(KTR_SYSRET);
	99	struct ktr_sysret ktp;
	100
	101	ktp.ktr_code = code;
	102	ktp.ktr_error = error;
	103	ktp.ktr_retval = retval; /* what about val2 ? */
	104
	105	kth->ktr_buf = (caddr_t)&ktp;
	106	kth->ktr_len = sizeof(struct ktr_sysret);
	107
	108	ktrwrite(vp, kth);
	109	FREE(kth, M_TEMP);
	110	}
	111
4c45483e	112	void
15637ed4 RG	113	ktrnamei(vp, path)
	114	struct vnode *vp;
	115	char *path;
	116	{
	117	struct ktr_header *kth = ktrgetheader(KTR_NAMEI);
	118
	119	kth->ktr_len = strlen(path);
	120	kth->ktr_buf = path;
	121
	122	ktrwrite(vp, kth);
	123	FREE(kth, M_TEMP);
	124	}
	125
4c45483e	126	void
15637ed4 RG	127	ktrgenio(vp, fd, rw, iov, len, error)
	128	struct vnode *vp;
	129	int fd;
	130	enum uio_rw rw;
	131	register struct iovec *iov;
4c45483e GW	132	int len;
4c45483e GW	133	int error;
15637ed4 RG	134	{
	135	struct ktr_header *kth = ktrgetheader(KTR_GENIO);
	136	register struct ktr_genio *ktp;
	137	register caddr_t cp;
	138	register int resid = len, cnt;
	139
	140	if (error)
	141	return;
	142	MALLOC(ktp, struct ktr_genio *, sizeof(struct ktr_genio) + len,
	143	M_TEMP, M_WAITOK);
	144	ktp->ktr_fd = fd;
	145	ktp->ktr_rw = rw;
	146	cp = (caddr_t)((char *)ktp + sizeof (struct ktr_genio));
	147	while (resid > 0) {
	148	if ((cnt = iov->iov_len) > resid)
	149	cnt = resid;
	150	if (copyin(iov->iov_base, cp, (unsigned)cnt))
	151	goto done;
	152	cp += cnt;
	153	resid -= cnt;
	154	iov++;
	155	}
	156	kth->ktr_buf = (caddr_t)ktp;
	157	kth->ktr_len = sizeof (struct ktr_genio) + len;
	158
	159	ktrwrite(vp, kth);
	160	done:
	161	FREE(kth, M_TEMP);
	162	FREE(ktp, M_TEMP);
	163	}
	164
4c45483e	165	void
15637ed4 RG	166	ktrpsig(vp, sig, action, mask, code)
15637ed4 RG	167	struct vnode *vp;
4c45483e	168	int sig;
15637ed4	169	sig_t action;
4c45483e GW	170	int mask;
4c45483e GW	171	int code;
15637ed4 RG	172	{
	173	struct ktr_header *kth = ktrgetheader(KTR_PSIG);
	174	struct ktr_psig kp;
	175
	176	kp.signo = (char)sig;
	177	kp.action = action;
	178	kp.mask = mask;
	179	kp.code = code;
	180	kth->ktr_buf = (caddr_t)&kp;
	181	kth->ktr_len = sizeof (struct ktr_psig);
	182
	183	ktrwrite(vp, kth);
	184	FREE(kth, M_TEMP);
	185	}
	186
	187	/* Interface and common routines */
	188
	189	/*
	190	* ktrace system call
	191	*/
3c7eb27c DG	192
	193	struct ktrace_args {
	194	char *fname;
	195	int ops;
	196	int facs;
	197	int pid;
	198	};
	199
15637ed4	200	/* ARGSUSED */
4c45483e	201	int
15637ed4 RG	202	ktrace(curp, uap, retval)
15637ed4 RG	203	struct proc *curp;
3c7eb27c	204	register struct ktrace_args *uap;
15637ed4 RG	205	int *retval;
	206	{
	207	register struct vnode *vp = NULL;
	208	register struct proc *p;
	209	struct pgrp *pg;
	210	int facs = uap->facs & ~KTRFAC_ROOT;
	211	int ops = KTROP(uap->ops);
	212	int descend = uap->ops & KTRFLAG_DESCEND;
	213	int ret = 0;
	214	int error = 0;
	215	struct nameidata nd;
	216
	217	if (ops != KTROP_CLEAR) {
	218	/*
	219	* an operation which requires a file argument.
	220	*/
	221	nd.ni_segflg = UIO_USERSPACE;
	222	nd.ni_dirp = uap->fname;
	223	if (error = vn_open(&nd, curp, FREAD\|FWRITE, 0))
	224	return (error);
	225	vp = nd.ni_vp;
	226	VOP_UNLOCK(vp);
	227	if (vp->v_type != VREG) {
	228	(void) vn_close(vp, FREAD\|FWRITE, curp->p_ucred, curp);
	229	return (EACCES);
	230	}
	231	}
	232	/*
	233	* Clear all uses of the tracefile
	234	*/
	235	if (ops == KTROP_CLEARFILE) {
	236	for (p = allproc; p != NULL; p = p->p_nxt) {
	237	if (p->p_tracep == vp) {
	238	if (ktrcanset(curp, p)) {
	239	p->p_tracep = NULL;
	240	p->p_traceflag = 0;
	241	(void) vn_close(vp, FREAD\|FWRITE,
	242	p->p_ucred, p);
	243	} else
	244	error = EPERM;
	245	}
	246	}
	247	goto done;
	248	}
	249	/*
	250	* need something to (un)trace (XXX - why is this here?)
	251	*/
	252	if (!facs) {
	253	error = EINVAL;
	254	goto done;
	255	}
	256	/*
	257	* do it
	258	*/
	259	if (uap->pid < 0) {
	260	/*
	261	* by process group
	262	*/
	263	pg = pgfind(-uap->pid);
	264	if (pg == NULL) {
	265	error = ESRCH;
	266	goto done;
	267	}
	268	for (p = pg->pg_mem; p != NULL; p = p->p_pgrpnxt)
269	if (descend)
270	ret \|= ktrsetchildren(curp, p, ops, facs, vp);
271	else
272	ret \|= ktrops(curp, p, ops, facs, vp);
273
274	} else {
275	/*
276	* by pid
277	*/
278	p = pfind(uap->pid);
279	if (p == NULL) {
280	error = ESRCH;
281	goto done;
282	}
283	if (descend)
284	ret \|= ktrsetchildren(curp, p, ops, facs, vp);
285	else
286	ret \|= ktrops(curp, p, ops, facs, vp);
287	}
288	if (!ret)
289	error = EPERM;
290	done:
291	if (vp != NULL)
292	(void) vn_close(vp, FWRITE, curp->p_ucred, curp);
293	return (error);
294	}
295
fde1aeb2	296	static int
15637ed4 RG	297	ktrops(curp, p, ops, facs, vp)
15637ed4 RG	298	struct proc curp, p;
4c45483e GW	299	int ops;
4c45483e GW	300	int facs;
15637ed4 RG	301	struct vnode *vp;
	302	{
	303
	304	if (!ktrcanset(curp, p))
	305	return (0);
	306	if (ops == KTROP_SET) {
	307	if (p->p_tracep != vp) {
	308	/*
	309	* if trace file already in use, relinquish
	310	*/
	311	if (p->p_tracep != NULL)
	312	vrele(p->p_tracep);
	313	VREF(vp);
	314	p->p_tracep = vp;
	315	}
	316	p->p_traceflag \|= facs;
	317	if (curp->p_ucred->cr_uid == 0)
	318	p->p_traceflag \|= KTRFAC_ROOT;
	319	} else {
	320	/* KTROP_CLEAR */
	321	if (((p->p_traceflag &= ~facs) & KTRFAC_MASK) == 0) {
	322	/* no more tracing */
	323	p->p_traceflag = 0;
	324	if (p->p_tracep != NULL) {
	325	vrele(p->p_tracep);
	326	p->p_tracep = NULL;
	327	}
	328	}
	329	}
	330
	331	return (1);
	332	}
	333
fde1aeb2	334	static int
15637ed4 RG	335	ktrsetchildren(curp, top, ops, facs, vp)
15637ed4 RG	336	struct proc curp, top;
4c45483e GW	337	int ops;
4c45483e GW	338	int facs;
15637ed4 RG	339	struct vnode *vp;
	340	{
	341	register struct proc *p;
	342	register int ret = 0;
	343
	344	p = top;
	345	for (;;) {
	346	ret \|= ktrops(curp, p, ops, facs, vp);
	347	/*
	348	* If this process has children, descend to them next,
	349	* otherwise do any siblings, and if done with this level,
	350	* follow back up the tree (but not past top).
	351	*/
	352	if (p->p_cptr)
	353	p = p->p_cptr;
	354	else if (p == top)
	355	return (ret);
	356	else if (p->p_osptr)
	357	p = p->p_osptr;
	358	else for (;;) {
	359	p = p->p_pptr;
	360	if (p == top)
	361	return (ret);
	362	if (p->p_osptr) {
	363	p = p->p_osptr;
	364	break;
	365	}
	366	}
	367	}
	368	/NOTREACHED/
	369	}
	370
4c45483e	371	static void
15637ed4 RG	372	ktrwrite(vp, kth)
	373	struct vnode *vp;
	374	register struct ktr_header *kth;
	375	{
	376	struct uio auio;
	377	struct iovec aiov[2];
	378	register struct proc p = curproc; / XXX */
	379	int error;
	380
	381	if (vp == NULL)
	382	return;
	383	auio.uio_iov = &aiov[0];
	384	auio.uio_offset = 0;
	385	auio.uio_segflg = UIO_SYSSPACE;
	386	auio.uio_rw = UIO_WRITE;
	387	aiov[0].iov_base = (caddr_t)kth;
	388	aiov[0].iov_len = sizeof(struct ktr_header);
	389	auio.uio_resid = sizeof(struct ktr_header);
	390	auio.uio_iovcnt = 1;
	391	auio.uio_procp = (struct proc *)0;
	392	if (kth->ktr_len > 0) {
	393	auio.uio_iovcnt++;
	394	aiov[1].iov_base = kth->ktr_buf;
	395	aiov[1].iov_len = kth->ktr_len;
	396	auio.uio_resid += kth->ktr_len;
	397	}
	398	VOP_LOCK(vp);
	399	error = VOP_WRITE(vp, &auio, IO_UNIT\|IO_APPEND, p->p_ucred);
	400	VOP_UNLOCK(vp);
	401	if (!error)
	402	return;
	403	/*
	404	* If error encountered, give up tracing on this vnode.
	405	*/
	406	log(LOG_NOTICE, "ktrace write failed, errno %d, tracing stopped\n",
	407	error);
	408	for (p = allproc; p != NULL; p = p->p_nxt) {
	409	if (p->p_tracep == vp) {
	410	p->p_tracep = NULL;
	411	p->p_traceflag = 0;
	412	vrele(vp);
	413	}
	414	}
	415	}
	416
	417	/*
	418	* Return true if caller has permission to set the ktracing state
	419	* of target. Essentially, the target can't possess any
	420	* more permissions than the caller. KTRFAC_ROOT signifies that
	421	* root previously set the tracing status on the target process, and
	422	* so, only root may further change it.
	423	*
	424	* TODO: check groups. use caller effective gid.
	425	*/
fde1aeb2	426	static int
15637ed4 RG	427	ktrcanset(callp, targetp)
	428	struct proc callp, targetp;
	429	{
	430	register struct pcred *caller = callp->p_cred;
	431	register struct pcred *target = targetp->p_cred;
	432
	433	if ((caller->pc_ucred->cr_uid == target->p_ruid &&
	434	target->p_ruid == target->p_svuid &&
	435	caller->p_rgid == target->p_rgid && /* XXX */
	436	target->p_rgid == target->p_svgid &&
	437	(targetp->p_traceflag & KTRFAC_ROOT) == 0) \|\|
	438	caller->pc_ucred->cr_uid == 0)
	439	return (1);
	440
	441	return (0);
	442	}
	443
	444	#endif