[apple/xnu.git] / bsd / kern / kern_ktrace.c

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
/*
 * Copyright (c) 1989, 1993
 *	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.
 *
 *	@(#)kern_ktrace.c	8.2 (Berkeley) 9/23/93
 */


#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/file.h>
#include <sys/namei.h>
#include <sys/vnode.h>
#include <sys/ktrace.h>
#include <sys/malloc.h>
#include <sys/syslog.h>

#include <sys/mount.h>

#if KTRACE

struct ktr_header *
ktrgetheader(type)
	int type;
{
	register struct ktr_header *kth;
	struct proc *p = current_proc();	/* 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, argsize, args)
	struct vnode *vp;
	register_t code;
	size_t argsize;
	register_t args[];
{
	struct	ktr_header *kth;
	struct	ktr_syscall *ktp;
	register len = sizeof(struct ktr_syscall) + argsize;
	struct proc *p = current_proc();	/* XXX */
	register_t *argp;
	int i;

	p->p_traceflag |= KTRFAC_ACTIVE;
	kth = ktrgetheader(KTR_SYSCALL);
	MALLOC(ktp, struct ktr_syscall *, len, M_TEMP, M_WAITOK);
	ktp->ktr_code = code;
	ktp->ktr_argsize = argsize;
	argp = (register_t *)((char *)ktp + sizeof(struct ktr_syscall));
	for (i = 0; i < (argsize / sizeof *argp); 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);
	p->p_traceflag &= ~KTRFAC_ACTIVE;
}

void
ktrsysret(vp, code, error, retval)
	struct vnode *vp;
	register_t code;
	int error;
	register_t retval;
{
	struct ktr_header *kth;
	struct ktr_sysret ktp;
	struct proc *p = current_proc();	/* XXX */

	p->p_traceflag |= KTRFAC_ACTIVE;
	kth = ktrgetheader(KTR_SYSRET);
	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);
	p->p_traceflag &= ~KTRFAC_ACTIVE;
}

void
ktrnamei(vp, path)
	struct vnode *vp;
	char *path;
{
	struct ktr_header *kth;
	struct proc *p = current_proc();	/* XXX */

	p->p_traceflag |= KTRFAC_ACTIVE;
	kth = ktrgetheader(KTR_NAMEI);
	kth->ktr_len = strlen(path);
	kth->ktr_buf = path;

	ktrwrite(vp, kth);
	FREE(kth, M_TEMP);
	p->p_traceflag &= ~KTRFAC_ACTIVE;
}

void
ktrgenio(vp, fd, rw, iov, len, error)
	struct vnode *vp;
	int fd;
	enum uio_rw rw;
	register struct iovec *iov;
	int len, error;
{
	struct ktr_header *kth;
	register struct ktr_genio *ktp;
	register caddr_t cp;
	register int resid = len, cnt;
	struct proc *p = current_proc();	/* XXX */
	
	if (error)
		return;
	p->p_traceflag |= KTRFAC_ACTIVE;
	kth = ktrgetheader(KTR_GENIO);
	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);
	p->p_traceflag &= ~KTRFAC_ACTIVE;
}

void
ktrpsig(vp, sig, action, mask, code)
	struct vnode *vp;
	int sig;
	sig_t action;
	int mask, code;
{
	struct ktr_header *kth;
	struct ktr_psig	kp;
	struct proc *p = current_proc();	/* XXX */

	p->p_traceflag |= KTRFAC_ACTIVE;
	kth = ktrgetheader(KTR_PSIG);
	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);
	p->p_traceflag &= ~KTRFAC_ACTIVE;
}

void
ktrcsw(vp, out, user)
	struct vnode *vp;
	int out, user;
{
	struct ktr_header *kth;
	struct	ktr_csw kc;
	struct proc *p = current_proc();	/* XXX */

	p->p_traceflag |= KTRFAC_ACTIVE;
	kth = ktrgetheader(KTR_CSW);
	kc.out = out;
	kc.user = user;
	kth->ktr_buf = (caddr_t)&kc;
	kth->ktr_len = sizeof (struct ktr_csw);

	ktrwrite(vp, kth);
	FREE(kth, M_TEMP);
	p->p_traceflag &= ~KTRFAC_ACTIVE;
}

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

	curp->p_traceflag |= KTRFAC_ACTIVE;
	if (ops != KTROP_CLEAR) {
		/*
		 * an operation which requires a file argument.
		 */
		NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, fname),
		    curp);
		if (error = vn_open(&nd, FREAD|FWRITE, 0)) {
			curp->p_traceflag &= ~KTRFAC_ACTIVE;
			return (error);
		}
		vp = nd.ni_vp;
		VOP_UNLOCK(vp, 0, p);
		if (vp->v_type != VREG) {
			(void) vn_close(vp, FREAD|FWRITE, curp->p_ucred, curp);
			curp->p_traceflag &= ~KTRFAC_ACTIVE;
			return (EACCES);
		}
	}
	/*
	 * Clear all uses of the tracefile
	 */
	if (ops == KTROP_CLEARFILE) {
		for (p = allproc.lh_first; p != 0; p = p->p_list.le_next) {
			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 (SCARG(uap, pid) < 0) {
		/*
		 * by process group
		 */
		pg = pgfind(-SCARG(uap, pid));
		if (pg == NULL) {
			error = ESRCH;
			goto done;
		}
		for (p = pg->pg_members.lh_first; p != 0; p = p->p_pglist.le_next)
			if (descend)
				ret |= ktrsetchildren(curp, p, ops, facs, vp);
			else 
				ret |= ktrops(curp, p, ops, facs, vp);
					
	} else {
		/*
		 * by pid
		 */
		p = pfind(SCARG(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);
	curp->p_traceflag &= ~KTRFAC_ACTIVE;
	return (error);
}

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

ktrsetchildren(curp, top, ops, facs, vp)
	struct proc *curp, *top;
	int ops, 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_children.lh_first)
			p = p->p_children.lh_first;
		else for (;;) {
			if (p == top)
				return (ret);
			if (p->p_sibling.le_next) {
				p = p->p_sibling.le_next;
				break;
			}
			p = p->p_pptr;
		}
	}
	/*NOTREACHED*/
}

ktrwrite(vp, kth)
	struct vnode *vp;
	register struct ktr_header *kth;
{
	struct uio auio;
	struct iovec aiov[2];
	register struct proc *p = current_proc();	/* 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;
	}
	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
	error = VOP_WRITE(vp, &auio, IO_UNIT|IO_APPEND, p->p_ucred);
	VOP_UNLOCK(vp, 0, p);
	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.lh_first; p != 0; p = p->p_list.le_next) {
		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
1c79356b A	1	/*
	2	* Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
	6	* The contents of this file constitute Original Code as defined in and
	7	* are subject to the Apple Public Source License Version 1.1 (the
	8	* "License"). You may not use this file except in compliance with the
	9	* License. Please obtain a copy of the License at
	10	* http://www.apple.com/publicsource and read it before using this file.
	11	*
	12	* This Original Code and all software distributed under the License are
	13	* distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	14	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	15	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	16	* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
	17	* License for the specific language governing rights and limitations
	18	* under the License.
	19	*
	20	* @APPLE_LICENSE_HEADER_END@
	21	*/
	22	/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
	23	/*
	24	* Copyright (c) 1989, 1993
	25	* The Regents of the University of California. All rights reserved.
	26	*
	27	* Redistribution and use in source and binary forms, with or without
	28	* modification, are permitted provided that the following conditions
	29	* are met:
	30	* 1. Redistributions of source code must retain the above copyright
	31	* notice, this list of conditions and the following disclaimer.
	32	* 2. Redistributions in binary form must reproduce the above copyright
	33	* notice, this list of conditions and the following disclaimer in the
	34	* documentation and/or other materials provided with the distribution.
	35	* 3. All advertising materials mentioning features or use of this software
	36	* must display the following acknowledgement:
	37	* This product includes software developed by the University of
	38	* California, Berkeley and its contributors.
	39	* 4. Neither the name of the University nor the names of its contributors
	40	* may be used to endorse or promote products derived from this software
	41	* without specific prior written permission.
	42	*
	43	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	44	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	45	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	46	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	47	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	48	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	49	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	50	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	51	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	52	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	53	* SUCH DAMAGE.
	54	*
	55	* @(#)kern_ktrace.c 8.2 (Berkeley) 9/23/93
	56	*/
	57
	58
	59	#include <sys/param.h>
	60	#include <sys/systm.h>
	61	#include <sys/proc.h>
	62	#include <sys/file.h>
	63	#include <sys/namei.h>
	64	#include <sys/vnode.h>
65	#include <sys/ktrace.h>
66	#include <sys/malloc.h>
67	#include <sys/syslog.h>
68
69	#include <sys/mount.h>
70
71	#if KTRACE
72
73	struct ktr_header *
74	ktrgetheader(type)
75	int type;
76	{
77	register struct ktr_header *kth;
78	struct proc p = current_proc(); / XXX */
79
80	MALLOC(kth, struct ktr_header *, sizeof (struct ktr_header),
81	M_TEMP, M_WAITOK);
82	kth->ktr_type = type;
83	microtime(&kth->ktr_time);
84	kth->ktr_pid = p->p_pid;
85	bcopy(p->p_comm, kth->ktr_comm, MAXCOMLEN);
86	return (kth);
87	}
88
89	void
90	ktrsyscall(vp, code, argsize, args)
91	struct vnode *vp;
92	register_t code;
93	size_t argsize;
94	register_t args[];
95	{
96	struct ktr_header *kth;
97	struct ktr_syscall *ktp;
98	register len = sizeof(struct ktr_syscall) + argsize;
99	struct proc p = current_proc(); / XXX */
100	register_t *argp;
101	int i;
102
103	p->p_traceflag \|= KTRFAC_ACTIVE;
104	kth = ktrgetheader(KTR_SYSCALL);
105	MALLOC(ktp, struct ktr_syscall *, len, M_TEMP, M_WAITOK);
106	ktp->ktr_code = code;
107	ktp->ktr_argsize = argsize;
108	argp = (register_t )((char )ktp + sizeof(struct ktr_syscall));
109	for (i = 0; i < (argsize / sizeof *argp); i++)
110	*argp++ = args[i];
111	kth->ktr_buf = (caddr_t)ktp;
112	kth->ktr_len = len;
113	ktrwrite(vp, kth);
114	FREE(ktp, M_TEMP);
115	FREE(kth, M_TEMP);
116	p->p_traceflag &= ~KTRFAC_ACTIVE;
117	}
118
119	void
120	ktrsysret(vp, code, error, retval)
121	struct vnode *vp;
122	register_t code;
123	int error;
124	register_t retval;
125	{
126	struct ktr_header *kth;
127	struct ktr_sysret ktp;
128	struct proc p = current_proc(); / XXX */
129
130	p->p_traceflag \|= KTRFAC_ACTIVE;
131	kth = ktrgetheader(KTR_SYSRET);
132	ktp.ktr_code = code;
133	ktp.ktr_error = error;
134	ktp.ktr_retval = retval; /* what about val2 ? */
135
136	kth->ktr_buf = (caddr_t)&ktp;
137	kth->ktr_len = sizeof(struct ktr_sysret);
138
139	ktrwrite(vp, kth);
140	FREE(kth, M_TEMP);
141	p->p_traceflag &= ~KTRFAC_ACTIVE;
142	}
143
144	void
145	ktrnamei(vp, path)
146	struct vnode *vp;
147	char *path;
148	{
149	struct ktr_header *kth;
150	struct proc p = current_proc(); / XXX */
151
152	p->p_traceflag \|= KTRFAC_ACTIVE;
153	kth = ktrgetheader(KTR_NAMEI);
154	kth->ktr_len = strlen(path);
155	kth->ktr_buf = path;
156
157	ktrwrite(vp, kth);
158	FREE(kth, M_TEMP);
159	p->p_traceflag &= ~KTRFAC_ACTIVE;
160	}
161
162	void
163	ktrgenio(vp, fd, rw, iov, len, error)
164	struct vnode *vp;
165	int fd;
166	enum uio_rw rw;
167	register struct iovec *iov;
168	int len, error;
169	{
170	struct ktr_header *kth;
171	register struct ktr_genio *ktp;
172	register caddr_t cp;
173	register int resid = len, cnt;
174	struct proc p = current_proc(); / XXX */
175
176	if (error)
177	return;
178	p->p_traceflag \|= KTRFAC_ACTIVE;
179	kth = ktrgetheader(KTR_GENIO);
180	MALLOC(ktp, struct ktr_genio *, sizeof(struct ktr_genio) + len,
181	M_TEMP, M_WAITOK);
182	ktp->ktr_fd = fd;
183	ktp->ktr_rw = rw;
184	cp = (caddr_t)((char *)ktp + sizeof (struct ktr_genio));
185	while (resid > 0) {
186	if ((cnt = iov->iov_len) > resid)
187	cnt = resid;
188	if (copyin(iov->iov_base, cp, (unsigned)cnt))
189	goto done;
190	cp += cnt;
191	resid -= cnt;
192	iov++;
193	}
194	kth->ktr_buf = (caddr_t)ktp;
195	kth->ktr_len = sizeof (struct ktr_genio) + len;
196
197	ktrwrite(vp, kth);
198	done:
199	FREE(kth, M_TEMP);
200	FREE(ktp, M_TEMP);
201	p->p_traceflag &= ~KTRFAC_ACTIVE;
202	}
203
204	void
205	ktrpsig(vp, sig, action, mask, code)
206	struct vnode *vp;
207	int sig;
208	sig_t action;
209	int mask, code;
210	{
211	struct ktr_header *kth;
212	struct ktr_psig kp;
213	struct proc p = current_proc(); / XXX */
214
215	p->p_traceflag \|= KTRFAC_ACTIVE;
216	kth = ktrgetheader(KTR_PSIG);
217	kp.signo = (char)sig;
218	kp.action = action;
219	kp.mask = mask;
220	kp.code = code;
221	kth->ktr_buf = (caddr_t)&kp;
222	kth->ktr_len = sizeof (struct ktr_psig);
223
224	ktrwrite(vp, kth);
225	FREE(kth, M_TEMP);
226	p->p_traceflag &= ~KTRFAC_ACTIVE;
227	}
228
229	void
230	ktrcsw(vp, out, user)
231	struct vnode *vp;
232	int out, user;
233	{
234	struct ktr_header *kth;
235	struct ktr_csw kc;
236	struct proc p = current_proc(); / XXX */
237
238	p->p_traceflag \|= KTRFAC_ACTIVE;
239	kth = ktrgetheader(KTR_CSW);
240	kc.out = out;
241	kc.user = user;
242	kth->ktr_buf = (caddr_t)&kc;
243	kth->ktr_len = sizeof (struct ktr_csw);
244
245	ktrwrite(vp, kth);
246	FREE(kth, M_TEMP);
247	p->p_traceflag &= ~KTRFAC_ACTIVE;
248	}
249
250	/* Interface and common routines */
251
252	/*
253	* ktrace system call
254	*/
255	struct ktrace_args {
256	char * fname;
257	int ops;
258	int facs;
259	int pid;
260	};
261	/* ARGSUSED */
262	int
263	ktrace(curp, uap, retval)
264	struct proc *curp;
265	register struct ktrace_args *uap;
266	register_t *retval;
267	{
268	register struct vnode *vp = NULL;
269	register struct proc *p;
270	struct pgrp *pg;
271	int facs = SCARG(uap, facs) & ~KTRFAC_ROOT;
272	int ops = KTROP(SCARG(uap, ops));
273	int descend = SCARG(uap, ops) & KTRFLAG_DESCEND;
274	int ret = 0;
275	int error = 0;
276	struct nameidata nd;
277
278	curp->p_traceflag \|= KTRFAC_ACTIVE;
279	if (ops != KTROP_CLEAR) {
280	/*
281	* an operation which requires a file argument.
282	*/
283	NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, fname),
284	curp);
285	if (error = vn_open(&nd, FREAD\|FWRITE, 0)) {
286	curp->p_traceflag &= ~KTRFAC_ACTIVE;
287	return (error);
288	}
289	vp = nd.ni_vp;
290	VOP_UNLOCK(vp, 0, p);
291	if (vp->v_type != VREG) {
292	(void) vn_close(vp, FREAD\|FWRITE, curp->p_ucred, curp);
293	curp->p_traceflag &= ~KTRFAC_ACTIVE;
294	return (EACCES);
295	}
296	}
297	/*
298	* Clear all uses of the tracefile
299	*/
300	if (ops == KTROP_CLEARFILE) {
301	for (p = allproc.lh_first; p != 0; p = p->p_list.le_next) {
302	if (p->p_tracep == vp) {
303	if (ktrcanset(curp, p)) {
304	p->p_tracep = NULL;
305	p->p_traceflag = 0;
306	(void) vn_close(vp, FREAD\|FWRITE,
307	p->p_ucred, p);
308	} else
309	error = EPERM;
310	}
311	}
312	goto done;
313	}
314	/*
315	* need something to (un)trace (XXX - why is this here?)
316	*/
317	if (!facs) {
318	error = EINVAL;
319	goto done;
320	}
321	/*
322	* do it
323	*/
324	if (SCARG(uap, pid) < 0) {
325	/*
326	* by process group
327	*/
328	pg = pgfind(-SCARG(uap, pid));
329	if (pg == NULL) {
330	error = ESRCH;
331	goto done;
332	}
333	for (p = pg->pg_members.lh_first; p != 0; p = p->p_pglist.le_next)
334	if (descend)
335	ret \|= ktrsetchildren(curp, p, ops, facs, vp);
336	else
337	ret \|= ktrops(curp, p, ops, facs, vp);
338
339	} else {
340	/*
341	* by pid
342	*/
343	p = pfind(SCARG(uap, pid));
344	if (p == NULL) {
345	error = ESRCH;
346	goto done;
347	}
348	if (descend)
349	ret \|= ktrsetchildren(curp, p, ops, facs, vp);
350	else
351	ret \|= ktrops(curp, p, ops, facs, vp);
352	}
353	if (!ret)
354	error = EPERM;
355	done:
356	if (vp != NULL)
357	(void) vn_close(vp, FWRITE, curp->p_ucred, curp);
358	curp->p_traceflag &= ~KTRFAC_ACTIVE;
359	return (error);
360	}
361
362	int
363	ktrops(curp, p, ops, facs, vp)
364	struct proc p, curp;
365	int ops, facs;
366	struct vnode *vp;
367	{
368
369	if (!ktrcanset(curp, p))
370	return (0);
371	if (ops == KTROP_SET) {
372	if (p->p_tracep != vp) {
373	/*
374	* if trace file already in use, relinquish
375	*/
376	if (p->p_tracep != NULL)
377	vrele(p->p_tracep);
378	VREF(vp);
379	p->p_tracep = vp;
380	}
381	p->p_traceflag \|= facs;
382	if (curp->p_ucred->cr_uid == 0)
383	p->p_traceflag \|= KTRFAC_ROOT;
384	} else {
385	/* KTROP_CLEAR */
386	if (((p->p_traceflag &= ~facs) & KTRFAC_MASK) == 0) {
387	/* no more tracing */
388	p->p_traceflag = 0;
389	if (p->p_tracep != NULL) {
390	vrele(p->p_tracep);
391	p->p_tracep = NULL;
392	}
393	}
394	}
395
396	return (1);
397	}
398
399	ktrsetchildren(curp, top, ops, facs, vp)
400	struct proc curp, top;
401	int ops, facs;
402	struct vnode *vp;
403	{
404	register struct proc *p;
405	register int ret = 0;
406
407	p = top;
408	for (;;) {
409	ret \|= ktrops(curp, p, ops, facs, vp);
410	/*
411	* If this process has children, descend to them next,
412	* otherwise do any siblings, and if done with this level,
413	* follow back up the tree (but not past top).
414	*/
415	if (p->p_children.lh_first)
416	p = p->p_children.lh_first;
417	else for (;;) {
418	if (p == top)
419	return (ret);
420	if (p->p_sibling.le_next) {
421	p = p->p_sibling.le_next;
422	break;
423	}
424	p = p->p_pptr;
425	}
426	}
427	/NOTREACHED/
428	}
429
430	ktrwrite(vp, kth)
431	struct vnode *vp;
432	register struct ktr_header *kth;
433	{
434	struct uio auio;
435	struct iovec aiov[2];
436	register struct proc p = current_proc(); / XXX */
437	int error;
438
439	if (vp == NULL)
440	return;
441	auio.uio_iov = &aiov[0];
442	auio.uio_offset = 0;
443	auio.uio_segflg = UIO_SYSSPACE;
444	auio.uio_rw = UIO_WRITE;
445	aiov[0].iov_base = (caddr_t)kth;
446	aiov[0].iov_len = sizeof(struct ktr_header);
447	auio.uio_resid = sizeof(struct ktr_header);
448	auio.uio_iovcnt = 1;
449	auio.uio_procp = (struct proc *)0;
450	if (kth->ktr_len > 0) {
451	auio.uio_iovcnt++;
452	aiov[1].iov_base = kth->ktr_buf;
453	aiov[1].iov_len = kth->ktr_len;
454	auio.uio_resid += kth->ktr_len;
455	}
456	vn_lock(vp, LK_EXCLUSIVE \| LK_RETRY, p);
457	error = VOP_WRITE(vp, &auio, IO_UNIT\|IO_APPEND, p->p_ucred);
458	VOP_UNLOCK(vp, 0, p);
459	if (!error)
460	return;
461	/*
462	* If error encountered, give up tracing on this vnode.
463	*/
464	log(LOG_NOTICE, "ktrace write failed, errno %d, tracing stopped\n",
465	error);
466	for (p = allproc.lh_first; p != 0; p = p->p_list.le_next) {
467	if (p->p_tracep == vp) {
468	p->p_tracep = NULL;
469	p->p_traceflag = 0;
470	vrele(vp);
471	}
472	}
473	}
474
475	/*
476	* Return true if caller has permission to set the ktracing state
477	* of target. Essentially, the target can't possess any
478	* more permissions than the caller. KTRFAC_ROOT signifies that
479	* root previously set the tracing status on the target process, and
480	* so, only root may further change it.
481	*
482	* TODO: check groups. use caller effective gid.
483	*/
484	ktrcanset(callp, targetp)
485	struct proc callp, targetp;
486	{
487	register struct pcred *caller = callp->p_cred;
488	register struct pcred *target = targetp->p_cred;
489
490	if ((caller->pc_ucred->cr_uid == target->p_ruid &&
491	target->p_ruid == target->p_svuid &&
492	caller->p_rgid == target->p_rgid && /* XXX */
493	target->p_rgid == target->p_svgid &&
494	(targetp->p_traceflag & KTRFAC_ROOT) == 0) \|\|
495	caller->pc_ucred->cr_uid == 0)
496	return (1);
497
498	return (0);
499	}
500
501	#endif