/* * Copyright (c) 2000-2010 Apple Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the License * may not be used to create, or enable the creation or redistribution of, * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. * * The 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, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */ /*- * 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. 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 8.1 (Berkeley) 6/14/93 */ /* HISTORY * 08-May-95 Mac Gillon (mgillon) at NeXT * Purged old history * New version based on 4.4 */ /* * NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce * support for mandatory and extensible security protections. This notice * is included in support of clause 2.2 (b) of the Apple Public License, * Version 2.0. */ #include <sys/param.h> #include <sys/proc_internal.h> #include <sys/kauth.h> #include <sys/mount_internal.h> #include <sys/vnode_internal.h> #include <sys/file_internal.h> #include <sys/syslog.h> #include <sys/kernel.h> #include <sys/namei.h> #include <sys/errno.h> #include <sys/acct.h> #include <sys/resourcevar.h> #include <sys/ioctl.h> #include <sys/tty.h> #include <sys/sysproto.h> #if CONFIG_MACF #include <security/mac_framework.h> #endif /* * 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. */ /* * Internal accounting functions. * The former's operation is described in Leffler, et al., and the latter * was provided by UCB with the 4.4BSD-Lite release */ comp_t encode_comp_t(uint32_t, uint32_t); void acctwatch(void *); /* * Accounting vnode pointer, and suspended accounting vnode pointer. States * are as follows: * * acctp suspend_acctp state * ------------- ------------ ------------------------------ * NULL NULL Accounting disabled * !NULL NULL Accounting enabled * NULL !NULL Accounting enabled, but suspended * !NULL !NULL <not allowed> */ struct vnode *acctp; struct vnode *suspend_acctp; /* * 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 */ static LCK_GRP_DECLARE(acct_subsys_lck_grp, "acct"); static LCK_MTX_DECLARE(acct_subsys_mutex, &acct_subsys_lck_grp); #define ACCT_SUBSYS_LOCK() lck_mtx_lock(&acct_subsys_mutex) #define ACCT_SUBSYS_UNLOCK() lck_mtx_unlock(&acct_subsys_mutex) /* * Accounting system call. Written based on the specification and * previous implementation done by Mark Tinguely. */ int acct(proc_t p, struct acct_args *uap, __unused int *retval) { struct nameidata nd; int error; struct vfs_context *ctx; ctx = vfs_context_current(); /* Make sure that the caller is root. */ if ((error = suser(vfs_context_ucred(ctx), &p->p_acflag))) { return error; } /* * If accounting is to be started to a file, open that file for * writing and make sure it's a 'normal'. */ if (uap->path != USER_ADDR_NULL) { NDINIT(&nd, LOOKUP, OP_OPEN, NOFOLLOW, UIO_USERSPACE, uap->path, ctx); if ((error = vn_open(&nd, FWRITE, 0))) { return error; } #if CONFIG_MACF error = mac_system_check_acct(vfs_context_ucred(ctx), nd.ni_vp); if (error) { vnode_put(nd.ni_vp); vn_close(nd.ni_vp, FWRITE, ctx); return error; } #endif vnode_put(nd.ni_vp); if (nd.ni_vp->v_type != VREG) { vn_close(nd.ni_vp, FWRITE, ctx); return EACCES; } } #if CONFIG_MACF else { error = mac_system_check_acct(vfs_context_ucred(ctx), NULL); if (error) { return error; } } #endif /* * If accounting was previously enabled, kill the old space-watcher, * close the file, and (if no new file was specified, leave). */ ACCT_SUBSYS_LOCK(); if (acctp != NULLVP || suspend_acctp != NULLVP) { untimeout(acctwatch, NULL); error = vn_close((acctp != NULLVP ? acctp : suspend_acctp), FWRITE, vfs_context_current()); acctp = suspend_acctp = NULLVP; } if (uap->path == USER_ADDR_NULL) { ACCT_SUBSYS_UNLOCK(); return error; } /* * Save the new accounting file vnode, and schedule the new * free space watcher. */ acctp = nd.ni_vp; ACCT_SUBSYS_UNLOCK(); acctwatch(NULL); return error; } /* * 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(proc_t p) { struct acct an_acct; struct rusage rup, *r; struct timeval ut, st, tmp; int t; int error; struct vnode *vp; kauth_cred_t safecred; struct session * sessp; struct tty *tp; /* If accounting isn't enabled, don't bother */ ACCT_SUBSYS_LOCK(); vp = acctp; if (vp == NULLVP) { ACCT_SUBSYS_UNLOCK(); return 0; } /* * Get process accounting information. */ /* (1) The name of the command that ran */ bcopy(p->p_comm, an_acct.ac_comm, sizeof an_acct.ac_comm); /* (2) The amount of user and system time that was used */ calcru(p, &ut, &st, NULL); an_acct.ac_utime = encode_comp_t((uint32_t)ut.tv_sec, ut.tv_usec); an_acct.ac_stime = encode_comp_t((uint32_t)st.tv_sec, st.tv_usec); /* (3) The elapsed time the commmand ran (and its starting time) */ an_acct.ac_btime = (u_int32_t)p->p_start.tv_sec; microtime(&tmp); timevalsub(&tmp, &p->p_start); an_acct.ac_etime = encode_comp_t((uint32_t)tmp.tv_sec, tmp.tv_usec); /* (4) The average amount of memory used */ proc_lock(p); rup = p->p_stats->p_ru; proc_unlock(p); r = &rup; tmp = ut; timevaladd(&tmp, &st); t = (int)(tmp.tv_sec * hz + tmp.tv_usec / tick); if (t) { an_acct.ac_mem = (u_int16_t)((r->ru_ixrss + r->ru_idrss + r->ru_isrss) / t); } else { an_acct.ac_mem = 0; } /* (5) The number of disk I/O operations done */ an_acct.ac_io = encode_comp_t((uint32_t)(r->ru_inblock + r->ru_oublock), 0); /* (6) The UID and GID of the process */ safecred = kauth_cred_proc_ref(p); an_acct.ac_uid = kauth_cred_getruid(safecred); an_acct.ac_gid = kauth_cred_getrgid(safecred); /* (7) The terminal from which the process was started */ sessp = proc_session(p); if ((p->p_flag & P_CONTROLT) && (sessp != SESSION_NULL) && ((tp = SESSION_TP(sessp)) != TTY_NULL)) { tty_lock(tp); an_acct.ac_tty = tp->t_dev; tty_unlock(tp); } else { an_acct.ac_tty = NODEV; } if (sessp != SESSION_NULL) { session_rele(sessp); } /* (8) The boolean flags that tell how the process terminated, etc. */ an_acct.ac_flag = (u_int8_t)p->p_acflag; /* * Now, just write the accounting information to the file. */ if ((error = vnode_getwithref(vp)) == 0) { error = vn_rdwr(UIO_WRITE, vp, (caddr_t)&an_acct, sizeof(an_acct), (off_t)0, UIO_SYSSPACE, IO_APPEND | IO_UNIT, safecred, (int *)0, p); vnode_put(vp); } kauth_cred_unref(&safecred); ACCT_SUBSYS_UNLOCK(); return error; } /* * 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. */ comp_t encode_comp_t(uint32_t s, uint32_t 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 (comp_t)exp; } /* * 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. */ /* ARGSUSED */ void acctwatch(__unused void *a) { vfs_context_t ctx = vfs_context_current(); struct vfs_attr va; VFSATTR_INIT(&va); VFSATTR_WANTED(&va, f_blocks); VFSATTR_WANTED(&va, f_bavail); ACCT_SUBSYS_LOCK(); if (suspend_acctp != NULLVP) { /* * Resuming accounting when accounting is suspended, and the * filesystem containing the suspended accounting file goes * below a low watermark */ if (suspend_acctp->v_type == VBAD) { (void) vn_close(suspend_acctp, FWRITE, vfs_context_kernel()); suspend_acctp = NULLVP; ACCT_SUBSYS_UNLOCK(); return; } (void)vfs_getattr(suspend_acctp->v_mount, &va, ctx); if (va.f_bavail > acctresume * va.f_blocks / 100) { acctp = suspend_acctp; suspend_acctp = NULLVP; log(LOG_NOTICE, "Accounting resumed\n"); } } else if (acctp != NULLVP) { /* * Suspending accounting when accounting is currently active, * and the filesystem containing the active accounting file * goes over a high watermark */ if (acctp->v_type == VBAD) { (void) vn_close(acctp, FWRITE, vfs_context_kernel()); acctp = NULLVP; ACCT_SUBSYS_UNLOCK(); return; } (void)vfs_getattr(acctp->v_mount, &va, ctx); if (va.f_bavail <= acctsuspend * va.f_blocks / 100) { suspend_acctp = acctp; acctp = NULLVP; log(LOG_NOTICE, "Accounting suspended\n"); } } else { ACCT_SUBSYS_UNLOCK(); return; } ACCT_SUBSYS_UNLOCK(); timeout(acctwatch, NULL, acctchkfreq * hz); }