/*-
* Copyright (c) 1982, 1986, 1989, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* 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. 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_acct.c 8.8 (Berkeley) 5/14/95
*/
/*-
* Copyright (c) 1994 Christopher G. Demetriou
*
* 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_acct.c 8.8 (Berkeley) 5/14/95
*/
/*
* The routines implemented in this file are described in:
* Leffler, et al.: The Design and Implementation of the 4.3BSD
* UNIX Operating System (Addison Welley, 1989)
* on pages 62-63.
*
* Arguably, to simplify accounting operations, this mechanism should
* be replaced by one in which an accounting log file (similar to /dev/klog)
* is read by a user process, etc. However, that has its own problems.
*/
/*
* Lock to serialize system calls and kernel threads.
*/
krwlock_t acct_lock;
/*
* The global accounting state and related data. Gain the mutex before
* accessing these variables.
*/
static enum {
ACCT_STOP,
ACCT_ACTIVE,
ACCT_SUSPENDED
} acct_state; /* The current accounting state. */
static struct vnode *acct_vp; /* Accounting vnode pointer. */
static kauth_cred_t acct_cred; /* Credential of accounting file
owner (i.e root). Used when
accounting file i/o. */
static struct lwp *acct_dkwatcher; /* Free disk space checker. */
/*
* Values associated with enabling and disabling accounting
*/
int acctsuspend = 2; /* stop accounting when < 2% free space left */
int acctresume = 4; /* resume when free space risen to > 4% */
int acctchkfreq = 15; /* frequency (in seconds) to check space */
/*
* Encode_comp_t converts from ticks in seconds and microseconds
* to ticks in 1/AHZ seconds. The encoding is described in
* Leffler, et al., on page 63.
*/
#define MANTSIZE 13 /* 13 bit mantissa. */
#define EXPSIZE 3 /* Base 8 (3 bit) exponent. */
#define MAXFRACT ((1 << MANTSIZE) - 1) /* Maximum fractional value. */
static comp_t
encode_comp_t(u_long s, u_long us)
{
int exp, rnd;
exp = 0;
rnd = 0;
s *= AHZ;
s += us / (1000000 / AHZ); /* Maximize precision. */
while (s > MAXFRACT) {
rnd = s & (1 << (EXPSIZE - 1)); /* Round up? */
s >>= EXPSIZE; /* Base 8 exponent == 3 bit shift. */
exp++;
}
/* If we need to round up, do it (and handle overflow correctly). */
if (rnd && (++s > MAXFRACT)) {
s >>= EXPSIZE;
exp++;
}
/* Clean it up and polish it off. */
exp <<= MANTSIZE; /* Shift the exponent into place */
exp += s; /* and add on the mantissa. */
return (exp);
}
static int
acct_chkfree(void)
{
int error;
struct statvfs *sb;
fsblkcnt_t bavail;
/*
* Periodically check the file system to see if accounting
* should be turned on or off. Beware the case where the vnode
* has been vgone()'d out from underneath us, e.g. when the file
* system containing the accounting file has been forcibly unmounted.
*/
static void
acctwatch(void *arg)
{
int error;
/*
* Accounting system call. Written based on the specification and
* previous implementation done by Mark Tinguely.
*/
int
sys_acct(struct lwp *l, const struct sys_acct_args *uap, register_t *retval)
{
/* {
syscallarg(const char *) path;
} */
struct pathbuf *pb;
struct vnode *vp;
int error;
/* Make sure that the caller is root. */
if ((error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_ACCOUNTING,
0, NULL, NULL, NULL)))
return (error);
/*
* If accounting is to be started to a file, open that file for
* writing and make sure it's a 'normal'.
*/
if (SCARG(uap, path) != NULL) {
struct vattr va;
size_t pad;
if ((pad = (va.va_size % sizeof(struct acct))) != 0) {
u_quad_t size = va.va_size - pad;
#ifdef DIAGNOSTIC
printf("Size of accounting file not a multiple of "
"%lu - incomplete record truncated\n",
(unsigned long)sizeof(struct acct));
#endif
vattr_null(&va);
va.va_size = size;
error = VOP_SETATTR(vp, &va, l->l_cred);
if (error != 0) {
VOP_UNLOCK(vp);
goto bad;
}
}
VOP_UNLOCK(vp);
}
rw_enter(&acct_lock, RW_WRITER);
/*
* If accounting was previously enabled, kill the old space-watcher,
* free credential for accounting file i/o,
* ... (and, if no new file was specified, leave).
*/
acct_stop();
if (SCARG(uap, path) == NULL)
goto out;
/*
* Save the new accounting file vnode and credential,
* and schedule the new free space watcher.
*/
acct_state = ACCT_ACTIVE;
acct_vp = vp;
acct_cred = l->l_cred;
kauth_cred_hold(acct_cred);
/*
* Write out process accounting information, on process exit.
* Data to be written out is specified in Leffler, et al.
* and are enumerated below. (They're also noted in the system
* "acct.h" header file.)
*/
int
acct_process(struct lwp *l)
{
struct acct acct;
struct timeval ut, st, tmp;
struct rusage *r;
int t, error = 0;
struct rlimit orlim;
struct proc *p = l->l_proc;
if (acct_state != ACCT_ACTIVE)
return 0;
memset(&acct, 0, sizeof(acct)); /* to zerofill padded data */
rw_enter(&acct_lock, RW_READER);
/* If accounting isn't enabled, don't bother */
if (acct_state != ACCT_ACTIVE)
goto out;
/*
* Temporarily raise the file limit so that accounting can't
* be stopped by the user.
*
* XXX We should think about the CPU limit, too.
*/
lim_privatise(p);
orlim = p->p_rlimit[RLIMIT_FSIZE];
/* Set current and max to avoid illegal values */
p->p_rlimit[RLIMIT_FSIZE].rlim_cur = RLIM_INFINITY;
p->p_rlimit[RLIMIT_FSIZE].rlim_max = RLIM_INFINITY;
/*
* Get process accounting information.
*/
/* (1) The name of the command that ran */
strncpy(acct.ac_comm, p->p_comm, sizeof(acct.ac_comm));
/* (2) The amount of user and system time that was used */
mutex_enter(p->p_lock);
calcru(p, &ut, &st, NULL, NULL);
mutex_exit(p->p_lock);
acct.ac_utime = encode_comp_t(ut.tv_sec, ut.tv_usec);
acct.ac_stime = encode_comp_t(st.tv_sec, st.tv_usec);
/* (3) The elapsed time the command ran (and its starting time) */
acct.ac_btime = p->p_stats->p_start.tv_sec;
getmicrotime(&tmp);
timersub(&tmp, &p->p_stats->p_start, &tmp);
acct.ac_etime = encode_comp_t(tmp.tv_sec, tmp.tv_usec);
/* (4) The average amount of memory used */
r = &p->p_stats->p_ru;
timeradd(&ut, &st, &tmp);
t = tmp.tv_sec * hz + tmp.tv_usec / tick;
if (t)
acct.ac_mem = (r->ru_ixrss + r->ru_idrss + r->ru_isrss) / t;
else
acct.ac_mem = 0;
/* (5) The number of disk I/O operations done */
acct.ac_io = encode_comp_t(r->ru_inblock + r->ru_oublock, 0);
/* (6) The UID and GID of the process */
acct.ac_uid = kauth_cred_getuid(l->l_cred);
acct.ac_gid = kauth_cred_getgid(l->l_cred);
/* (7) The terminal from which the process was started */
mutex_enter(&proc_lock);
if ((p->p_lflag & PL_CONTROLT) && p->p_pgrp->pg_session->s_ttyp)
acct.ac_tty = p->p_pgrp->pg_session->s_ttyp->t_dev;
else
acct.ac_tty = NODEV;
mutex_exit(&proc_lock);
/* (8) The boolean flags that tell how the process terminated, etc. */
acct.ac_flag = p->p_acflag;
/*
* Now, just write the accounting information to the file.
*/
error = vn_rdwr(UIO_WRITE, acct_vp, (void *)&acct,
sizeof(acct), (off_t)0, UIO_SYSSPACE, IO_APPEND|IO_UNIT,
acct_cred, NULL, NULL);
if (error != 0)
log(LOG_ERR, "Accounting: write failed %d\n", error);
/* Restore limit - rather pointless since process is about to exit */
p->p_rlimit[RLIMIT_FSIZE] = orlim;
