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

/*
 * Copyright (c) 1989 The Regents of the University of California.
 * All rights reserved.
 *
 * %sccs.include.redist.c%
 *
 *	@(#)kern_ktrace.c	7.15 (Berkeley) %G%
 */

#ifdef KTRACE

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

struct ktr_header *
ktrgetheader(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);
}

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);
}

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);
}

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);
}

ktrgenio(vp, fd, rw, iov, len, error)
	struct vnode *vp;
	int fd;
	enum uio_rw rw;
	register struct iovec *iov;
{
	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);
}

ktrpsig(vp, sig, action, mask, code)
	struct	vnode *vp;
	sig_t	action;
{
	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
 */
/* ARGSUSED */
ktrace(curp, uap, retval)
	struct proc *curp;
	register struct args {
		char	*fname;
		int	ops;
		int	facs;
		int	pid;
	} *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);
}

ktrops(curp, p, ops, facs, vp)
	struct proc *curp, *p;
	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);
}

ktrsetchildren(curp, top, ops, facs, vp)
	struct proc *curp, *top;
	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*/
}

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.
 */
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
2d68027d MT	1	/*
	2	* Copyright (c) 1989 The Regents of the University of California.
	3	* All rights reserved.
	4	*
dbf0c423	5	* %sccs.include.redist.c%
2d68027d	6	*
79583d0d	7	* @(#)kern_ktrace.c 7.15 (Berkeley) %G%
2d68027d MT	8	*/
	9
	10	#ifdef KTRACE
	11
	12	#include "param.h"
2d68027d	13	#include "proc.h"
c4ec2128	14	#include "file.h"
48826579	15	#include "namei.h"
c4ec2128	16	#include "vnode.h"
2d68027d MT	17	#include "ktrace.h"
2d68027d MT	18	#include "malloc.h"
9db11bbb	19	#include "syslog.h"
2d68027d MT	20
	21	struct ktr_header *
	22	ktrgetheader(type)
	23	{
	24	register struct ktr_header *kth;
48826579	25	struct proc p = curproc; / XXX */
2d68027d MT	26
	27	MALLOC(kth, struct ktr_header *, sizeof (struct ktr_header),
	28	M_TEMP, M_WAITOK);
2d68027d	29	kth->ktr_type = type;
f73d8bd6	30	microtime(&kth->ktr_time);
b98b2de8 MK	31	kth->ktr_pid = p->p_pid;
b98b2de8 MK	32	bcopy(p->p_comm, kth->ktr_comm, MAXCOMLEN);
2d68027d MT	33	return (kth);
	34	}
	35
8b24ca5d	36	ktrsyscall(vp, code, narg, args)
c4ec2128	37	struct vnode *vp;
8b24ca5d	38	int code, narg, args[];
2d68027d MT	39	{
	40	struct ktr_header *kth = ktrgetheader(KTR_SYSCALL);
	41	struct ktr_syscall *ktp;
	42	register len = sizeof(struct ktr_syscall) + (narg * sizeof(int));
	43	int *argp, i;
	44
2d68027d	45	MALLOC(ktp, struct ktr_syscall *, len, M_TEMP, M_WAITOK);
2d68027d MT	46	ktp->ktr_code = code;
	47	ktp->ktr_narg = narg;
	48	argp = (int )((char )ktp + sizeof(struct ktr_syscall));
	49	for (i = 0; i < narg; i++)
8b24ca5d	50	*argp++ = args[i];
2d68027d MT	51	kth->ktr_buf = (caddr_t)ktp;
2d68027d MT	52	kth->ktr_len = len;
c4ec2128	53	ktrwrite(vp, kth);
2d68027d MT	54	FREE(ktp, M_TEMP);
	55	FREE(kth, M_TEMP);
	56	}
	57
8b24ca5d	58	ktrsysret(vp, code, error, retval)
c4ec2128	59	struct vnode *vp;
8b24ca5d	60	int code, error, retval;
2d68027d MT	61	{
2d68027d MT	62	struct ktr_header *kth = ktrgetheader(KTR_SYSRET);
a97cc92e	63	struct ktr_sysret ktp;
2d68027d	64
a97cc92e	65	ktp.ktr_code = code;
8b24ca5d KM	66	ktp.ktr_error = error;
8b24ca5d KM	67	ktp.ktr_retval = retval; /* what about val2 ? */
2d68027d	68
a97cc92e	69	kth->ktr_buf = (caddr_t)&ktp;
2d68027d MT	70	kth->ktr_len = sizeof(struct ktr_sysret);
2d68027d MT	71
c4ec2128	72	ktrwrite(vp, kth);
2d68027d MT	73	FREE(kth, M_TEMP);
	74	}
	75
c4ec2128 KM	76	ktrnamei(vp, path)
c4ec2128 KM	77	struct vnode *vp;
2d68027d MT	78	char *path;
	79	{
	80	struct ktr_header *kth = ktrgetheader(KTR_NAMEI);
	81
2d68027d MT	82	kth->ktr_len = strlen(path);
	83	kth->ktr_buf = path;
	84
c4ec2128	85	ktrwrite(vp, kth);
2d68027d MT	86	FREE(kth, M_TEMP);
	87	}
	88
8b24ca5d	89	ktrgenio(vp, fd, rw, iov, len, error)
c4ec2128	90	struct vnode *vp;
8b24ca5d	91	int fd;
f73d8bd6 MT	92	enum uio_rw rw;
	93	register struct iovec *iov;
	94	{
	95	struct ktr_header *kth = ktrgetheader(KTR_GENIO);
	96	register struct ktr_genio *ktp;
	97	register caddr_t cp;
	98	register int resid = len, cnt;
	99
9db11bbb	100	if (error)
f73d8bd6 MT	101	return;
	102	MALLOC(ktp, struct ktr_genio *, sizeof(struct ktr_genio) + len,
	103	M_TEMP, M_WAITOK);
f73d8bd6 MT	104	ktp->ktr_fd = fd;
	105	ktp->ktr_rw = rw;
	106	cp = (caddr_t)((char *)ktp + sizeof (struct ktr_genio));
	107	while (resid > 0) {
	108	if ((cnt = iov->iov_len) > resid)
	109	cnt = resid;
e5e5e641	110	if (copyin(iov->iov_base, cp, (unsigned)cnt))
f73d8bd6 MT	111	goto done;
	112	cp += cnt;
	113	resid -= cnt;
	114	iov++;
	115	}
	116	kth->ktr_buf = (caddr_t)ktp;
	117	kth->ktr_len = sizeof (struct ktr_genio) + len;
	118
c4ec2128	119	ktrwrite(vp, kth);
f73d8bd6 MT	120	done:
	121	FREE(kth, M_TEMP);
	122	FREE(ktp, M_TEMP);
	123	}
	124
a97cc92e MT	125	ktrpsig(vp, sig, action, mask, code)
	126	struct vnode *vp;
	127	sig_t action;
	128	{
	129	struct ktr_header *kth = ktrgetheader(KTR_PSIG);
	130	struct ktr_psig kp;
	131
a97cc92e MT	132	kp.signo = (char)sig;
	133	kp.action = action;
	134	kp.mask = mask;
	135	kp.code = code;
	136	kth->ktr_buf = (caddr_t)&kp;
	137	kth->ktr_len = sizeof (struct ktr_psig);
	138
	139	ktrwrite(vp, kth);
	140	FREE(kth, M_TEMP);
	141	}
	142
	143	/* Interface and common routines */
	144
2d68027d MT	145	/*
	146	* ktrace system call
	147	*/
8b24ca5d KM	148	/* ARGSUSED */
	149	ktrace(curp, uap, retval)
	150	struct proc *curp;
	151	register struct args {
2d68027d MT	152	char *fname;
	153	int ops;
	154	int facs;
f73d8bd6	155	int pid;
8b24ca5d KM	156	} *uap;
	157	int *retval;
	158	{
c4ec2128	159	register struct vnode *vp = NULL;
2d68027d MT	160	register struct proc *p;
2d68027d MT	161	struct pgrp *pg;
9db11bbb MT	162	int facs = uap->facs & ~KTRFAC_ROOT;
	163	int ops = KTROP(uap->ops);
	164	int descend = uap->ops & KTRFLAG_DESCEND;
	165	int ret = 0;
8b24ca5d	166	int error = 0;
b98b2de8	167	struct nameidata nd;
2d68027d	168
2d68027d MT	169	if (ops != KTROP_CLEAR) {
	170	/*
	171	* an operation which requires a file argument.
	172	*/
b98b2de8 MK	173	nd.ni_segflg = UIO_USERSPACE;
	174	nd.ni_dirp = uap->fname;
	175	if (error = vn_open(&nd, curp, FREAD\|FWRITE, 0))
d9c2f47f	176	return (error);
b98b2de8	177	vp = nd.ni_vp;
ead191fe	178	VOP_UNLOCK(vp);
c4ec2128	179	if (vp->v_type != VREG) {
79583d0d	180	(void) vn_close(vp, FREAD\|FWRITE, curp->p_ucred, curp);
d9c2f47f	181	return (EACCES);
2d68027d	182	}
2d68027d MT	183	}
	184	/*
	185	* Clear all uses of the tracefile
	186	*/
	187	if (ops == KTROP_CLEARFILE) {
	188	for (p = allproc; p != NULL; p = p->p_nxt) {
c4ec2128	189	if (p->p_tracep == vp) {
9db11bbb MT	190	if (ktrcanset(curp, p)) {
	191	p->p_tracep = NULL;
	192	p->p_traceflag = 0;
79583d0d KM	193	(void) vn_close(vp, FREAD\|FWRITE,
79583d0d KM	194	p->p_ucred, p);
9db11bbb MT	195	} else
9db11bbb MT	196	error = EPERM;
2d68027d MT	197	}
	198	}
	199	goto done;
	200	}
2d68027d	201	/*
9db11bbb	202	* need something to (un)trace (XXX - why is this here?)
2d68027d MT	203	*/
2d68027d MT	204	if (!facs) {
8b24ca5d	205	error = EINVAL;
2d68027d MT	206	goto done;
2d68027d MT	207	}
a97cc92e	208	/*
9db11bbb	209	* do it
a97cc92e	210	*/
2d68027d	211	if (uap->pid < 0) {
9db11bbb MT	212	/*
	213	* by process group
	214	*/
2d68027d MT	215	pg = pgfind(-uap->pid);
2d68027d MT	216	if (pg == NULL) {
8b24ca5d	217	error = ESRCH;
2d68027d MT	218	goto done;
	219	}
	220	for (p = pg->pg_mem; p != NULL; p = p->p_pgrpnxt)
9db11bbb MT	221	if (descend)
9db11bbb MT	222	ret \|= ktrsetchildren(curp, p, ops, facs, vp);
2d68027d	223	else
9db11bbb	224	ret \|= ktrops(curp, p, ops, facs, vp);
2d68027d MT	225
2d68027d MT	226	} else {
9db11bbb MT	227	/*
	228	* by pid
	229	*/
2d68027d MT	230	p = pfind(uap->pid);
2d68027d MT	231	if (p == NULL) {
8b24ca5d	232	error = ESRCH;
2d68027d MT	233	goto done;
2d68027d MT	234	}
9db11bbb MT	235	if (descend)
9db11bbb MT	236	ret \|= ktrsetchildren(curp, p, ops, facs, vp);
2d68027d	237	else
9db11bbb	238	ret \|= ktrops(curp, p, ops, facs, vp);
2d68027d	239	}
f73d8bd6	240	if (!ret)
8b24ca5d	241	error = EPERM;
2d68027d	242	done:
c4ec2128	243	if (vp != NULL)
79583d0d	244	(void) vn_close(vp, FWRITE, curp->p_ucred, curp);
d9c2f47f	245	return (error);
2d68027d MT	246	}
2d68027d MT	247
9db11bbb MT	248	ktrops(curp, p, ops, facs, vp)
9db11bbb MT	249	struct proc curp, p;
c4ec2128	250	struct vnode *vp;
2d68027d	251	{
f73d8bd6	252
9db11bbb	253	if (!ktrcanset(curp, p))
d9c2f47f	254	return (0);
2d68027d	255	if (ops == KTROP_SET) {
a97cc92e	256	if (p->p_tracep != vp) {
2d68027d MT	257	/*
	258	* if trace file already in use, relinquish
	259	*/
	260	if (p->p_tracep != NULL)
c4ec2128	261	vrele(p->p_tracep);
2c0d2f20	262	VREF(vp);
c4ec2128	263	p->p_tracep = vp;
2d68027d MT	264	}
2d68027d MT	265	p->p_traceflag \|= facs;
b98b2de8	266	if (curp->p_ucred->cr_uid == 0)
9db11bbb	267	p->p_traceflag \|= KTRFAC_ROOT;
2d68027d MT	268	} else {
2d68027d MT	269	/* KTROP_CLEAR */
9db11bbb	270	if (((p->p_traceflag &= ~facs) & KTRFAC_MASK) == 0) {
a97cc92e MT	271	/* no more tracing */
a97cc92e MT	272	p->p_traceflag = 0;
2d68027d	273	if (p->p_tracep != NULL) {
c4ec2128	274	vrele(p->p_tracep);
2d68027d MT	275	p->p_tracep = NULL;
2d68027d MT	276	}
2d68027d MT	277	}
2d68027d MT	278	}
f73d8bd6	279
9db11bbb	280	return (1);
2d68027d	281	}
f73d8bd6	282
9db11bbb MT	283	ktrsetchildren(curp, top, ops, facs, vp)
9db11bbb MT	284	struct proc curp, top;
c4ec2128	285	struct vnode *vp;
2d68027d MT	286	{
2d68027d MT	287	register struct proc *p;
f73d8bd6	288	register int ret = 0;
2d68027d MT	289
	290	p = top;
	291	for (;;) {
9db11bbb	292	ret \|= ktrops(curp, p, ops, facs, vp);
2d68027d MT	293	/*
	294	* If this process has children, descend to them next,
	295	* otherwise do any siblings, and if done with this level,
	296	* follow back up the tree (but not past top).
	297	*/
	298	if (p->p_cptr)
	299	p = p->p_cptr;
	300	else if (p == top)
9db11bbb	301	return (ret);
2d68027d MT	302	else if (p->p_osptr)
	303	p = p->p_osptr;
	304	else for (;;) {
	305	p = p->p_pptr;
	306	if (p == top)
9db11bbb	307	return (ret);
2d68027d MT	308	if (p->p_osptr) {
	309	p = p->p_osptr;
	310	break;
	311	}
	312	}
	313	}
f73d8bd6	314	/NOTREACHED/
2d68027d MT	315	}
2d68027d MT	316
c4ec2128 KM	317	ktrwrite(vp, kth)
	318	struct vnode *vp;
	319	register struct ktr_header *kth;
2d68027d	320	{
c4ec2128 KM	321	struct uio auio;
c4ec2128 KM	322	struct iovec aiov[2];
48826579	323	register struct proc p = curproc; / XXX */
aeb44310	324	int error;
c4ec2128 KM	325
c4ec2128 KM	326	if (vp == NULL)
f73d8bd6	327	return;
c4ec2128 KM	328	auio.uio_iov = &aiov[0];
	329	auio.uio_offset = 0;
	330	auio.uio_segflg = UIO_SYSSPACE;
	331	auio.uio_rw = UIO_WRITE;
	332	aiov[0].iov_base = (caddr_t)kth;
	333	aiov[0].iov_len = sizeof(struct ktr_header);
	334	auio.uio_resid = sizeof(struct ktr_header);
	335	auio.uio_iovcnt = 1;
48826579	336	auio.uio_procp = (struct proc *)0;
2d68027d	337	if (kth->ktr_len > 0) {
c4ec2128 KM	338	auio.uio_iovcnt++;
	339	aiov[1].iov_base = kth->ktr_buf;
	340	aiov[1].iov_len = kth->ktr_len;
	341	auio.uio_resid += kth->ktr_len;
2d68027d	342	}
aeb44310	343	VOP_LOCK(vp);
48826579	344	error = VOP_WRITE(vp, &auio, IO_UNIT\|IO_APPEND, p->p_ucred);
aeb44310	345	VOP_UNLOCK(vp);
e5e5e641 KM	346	if (!error)
	347	return;
	348	/*
	349	* If error encountered, give up tracing on this vnode.
	350	*/
b98b2de8 MK	351	log(LOG_NOTICE, "ktrace write failed, errno %d, tracing stopped\n",
b98b2de8 MK	352	error);
e5e5e641 KM	353	for (p = allproc; p != NULL; p = p->p_nxt) {
	354	if (p->p_tracep == vp) {
	355	p->p_tracep = NULL;
	356	p->p_traceflag = 0;
	357	vrele(vp);
	358	}
	359	}
2d68027d	360	}
9db11bbb MT	361
	362	/*
	363	* Return true if caller has permission to set the ktracing state
	364	* of target. Essentially, the target can't possess any
	365	* more permissions than the caller. KTRFAC_ROOT signifies that
	366	* root previously set the tracing status on the target process, and
	367	* so, only root may further change it.
	368	*
b98b2de8	369	* TODO: check groups. use caller effective gid.
9db11bbb	370	*/
b98b2de8 MK	371	ktrcanset(callp, targetp)
b98b2de8 MK	372	struct proc callp, targetp;
9db11bbb	373	{
b98b2de8 MK	374	register struct pcred *caller = callp->p_cred;
	375	register struct pcred *target = targetp->p_cred;
	376
	377	if ((caller->pc_ucred->cr_uid == target->p_ruid &&
9db11bbb MT	378	target->p_ruid == target->p_svuid &&
	379	caller->p_rgid == target->p_rgid && /* XXX */
	380	target->p_rgid == target->p_svgid &&
b98b2de8 MK	381	(targetp->p_traceflag & KTRFAC_ROOT) == 0) \|\|
b98b2de8 MK	382	caller->pc_ucred->cr_uid == 0)
9db11bbb MT	383	return (1);
	384
	385	return (0);
	386	}
	387
2d68027d	388	#endif