freebsd-dev/sys/dev/filemon/filemon_wrapper.c
David E. O'Brien eb9aea5ac0 Add the 'filemon' device. 'filemon' is a kernel module that provides a device
interface for processes to record system calls of its children.

Submitted by:	Juniper Networks.
2012-06-04 22:54:19 +00:00

747 lines
20 KiB
C

/*-
* Copyright (c) 2011, David E. O'Brien.
* Copyright (c) 2009-2011, Juniper Networks, Inc.
* 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.
*
* THIS SOFTWARE IS PROVIDED BY JUNIPER NETWORKS 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 JUNIPER NETWORKS 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#if __FreeBSD_version > 800032
#define FILEMON_HAS_LINKAT
#endif
#if __FreeBSD_version < 900044 /* r225617 (2011-09-16) failed to bump
__FreeBSD_version. This really should
be based on "900045". "900044" is r225469
(2011-09-10) so this code is broken for
9-CURRENT September 10th-16th. */
#define sys_chdir chdir
#define sys_execve execve
#define sys_fork fork
#define sys_link link
#define sys_open open
#define sys_rename rename
#define sys_stat stat
#define sys_symlink symlink
#define sys_unlink unlink
#define sys_vfork vfork
#define sys_sys_exit sys_exit
#ifdef FILEMON_HAS_LINKAT
#define sys_linkat linkat
#endif
#endif /* __FreeBSD_version */
static void
filemon_output(struct filemon *filemon, char *msg, size_t len)
{
struct uio auio;
struct iovec aiov;
if (filemon->fp == NULL)
return;
aiov.iov_base = msg;
aiov.iov_len = len;
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_resid = len;
auio.uio_segflg = UIO_SYSSPACE;
auio.uio_rw = UIO_WRITE;
auio.uio_td = curthread;
auio.uio_offset = (off_t) -1;
bwillwrite();
fo_write(filemon->fp, &auio, curthread->td_ucred, 0, curthread);
}
static struct filemon *
filemon_pid_check(struct proc *p)
{
struct filemon *filemon;
TAILQ_FOREACH(filemon, &filemons_inuse, link) {
if (p->p_pid == filemon->pid)
return (filemon);
}
if (p->p_pptr == NULL)
return (NULL);
return (filemon_pid_check(p->p_pptr));
}
static void
filemon_comment(struct filemon *filemon)
{
int len;
struct timeval now;
/* Load timestamp before locking. Less accurate but less contention. */
getmicrotime(&now);
/* Grab a read lock on the filemon inuse list. */
filemon_lock_read();
/* Lock the found filemon structure. */
filemon_filemon_lock(filemon);
len = snprintf(filemon->msgbufr, sizeof(filemon->msgbufr),
"# filemon version %d\n# Target pid %d\n# Start %ju.%06ju\nV %d\n",
FILEMON_VERSION, curproc->p_pid, (uintmax_t)now.tv_sec,
(uintmax_t)now.tv_usec, FILEMON_VERSION);
filemon_output(filemon, filemon->msgbufr, len);
/* Unlock the found filemon structure. */
filemon_filemon_unlock(filemon);
/* Release the read lock. */
filemon_unlock_read();
}
static int
filemon_wrapper_chdir(struct thread *td, struct chdir_args *uap)
{
int ret;
size_t done;
size_t len;
struct filemon *filemon;
if ((ret = sys_chdir(td, uap)) == 0) {
/* Grab a read lock on the filemon inuse list. */
filemon_lock_read();
if ((filemon = filemon_pid_check(curproc)) != NULL) {
/* Lock the found filemon structure. */
filemon_filemon_lock(filemon);
copyinstr(uap->path, filemon->fname1,
sizeof(filemon->fname1), &done);
len = snprintf(filemon->msgbufr,
sizeof(filemon->msgbufr), "C %d %s\n",
curproc->p_pid, filemon->fname1);
filemon_output(filemon, filemon->msgbufr, len);
/* Unlock the found filemon structure. */
filemon_filemon_unlock(filemon);
}
/* Release the read lock. */
filemon_unlock_read();
}
return (ret);
}
static int
filemon_wrapper_execve(struct thread *td, struct execve_args *uap)
{
char fname[MAXPATHLEN];
int ret;
size_t done;
size_t len;
struct filemon *filemon;
copyinstr(uap->fname, fname, sizeof(fname), &done);
if ((ret = sys_execve(td, uap)) == 0) {
/* Grab a read lock on the filemon inuse list. */
filemon_lock_read();
if ((filemon = filemon_pid_check(curproc)) != NULL) {
/* Lock the found filemon structure. */
filemon_filemon_lock(filemon);
len = snprintf(filemon->msgbufr,
sizeof(filemon->msgbufr), "E %d %s\n",
curproc->p_pid, fname);
filemon_output(filemon, filemon->msgbufr, len);
/* Unlock the found filemon structure. */
filemon_filemon_unlock(filemon);
}
/* Release the read lock. */
filemon_unlock_read();
}
return (ret);
}
#if defined(COMPAT_IA32) || defined(COMPAT_FREEBSD32) || defined(COMPAT_ARCH32)
static int
filemon_wrapper_freebsd32_execve(struct thread *td,
struct freebsd32_execve_args *uap)
{
char fname[MAXPATHLEN];
int ret;
size_t done;
size_t len;
struct filemon *filemon;
copyinstr(uap->fname, fname, sizeof(fname), &done);
if ((ret = freebsd32_execve(td, uap)) == 0) {
/* Grab a read lock on the filemon inuse list. */
filemon_lock_read();
if ((filemon = filemon_pid_check(curproc)) != NULL) {
/* Lock the found filemon structure. */
filemon_filemon_lock(filemon);
len = snprintf(filemon->msgbufr,
sizeof(filemon->msgbufr), "E %d %s\n",
curproc->p_pid, fname);
filemon_output(filemon, filemon->msgbufr, len);
/* Unlock the found filemon structure. */
filemon_filemon_unlock(filemon);
}
/* Release the read lock. */
filemon_unlock_read();
}
return (ret);
}
#endif
static int
filemon_wrapper_fork(struct thread *td, struct fork_args *uap)
{
int ret;
size_t len;
struct filemon *filemon;
if ((ret = sys_fork(td, uap)) == 0) {
/* Grab a read lock on the filemon inuse list. */
filemon_lock_read();
if ((filemon = filemon_pid_check(curproc)) != NULL) {
/* Lock the found filemon structure. */
filemon_filemon_lock(filemon);
len = snprintf(filemon->msgbufr,
sizeof(filemon->msgbufr), "F %d %ld\n",
curproc->p_pid, (long)curthread->td_retval[0]);
filemon_output(filemon, filemon->msgbufr, len);
/* Unlock the found filemon structure. */
filemon_filemon_unlock(filemon);
}
/* Release the read lock. */
filemon_unlock_read();
}
return (ret);
}
static int
filemon_wrapper_open(struct thread *td, struct open_args *uap)
{
int ret;
size_t done;
size_t len;
struct filemon *filemon;
if ((ret = sys_open(td, uap)) == 0) {
/* Grab a read lock on the filemon inuse list. */
filemon_lock_read();
if ((filemon = filemon_pid_check(curproc)) != NULL) {
/* Lock the found filemon structure. */
filemon_filemon_lock(filemon);
copyinstr(uap->path, filemon->fname1,
sizeof(filemon->fname1), &done);
if (uap->flags & O_RDWR) {
/*
* We'll get the W record below, but need
* to also output an R to distingish from
* O_WRONLY.
*/
len = snprintf(filemon->msgbufr,
sizeof(filemon->msgbufr), "R %d %s\n",
curproc->p_pid, filemon->fname1);
filemon_output(filemon, filemon->msgbufr, len);
}
len = snprintf(filemon->msgbufr,
sizeof(filemon->msgbufr), "%c %d %s\n",
(uap->flags & O_ACCMODE) ? 'W':'R',
curproc->p_pid, filemon->fname1);
filemon_output(filemon, filemon->msgbufr, len);
/* Unlock the found filemon structure. */
filemon_filemon_unlock(filemon);
}
/* Release the read lock. */
filemon_unlock_read();
}
return (ret);
}
static int
filemon_wrapper_rename(struct thread *td, struct rename_args *uap)
{
int ret;
size_t done;
size_t len;
struct filemon *filemon;
if ((ret = sys_rename(td, uap)) == 0) {
/* Grab a read lock on the filemon inuse list. */
filemon_lock_read();
if ((filemon = filemon_pid_check(curproc)) != NULL) {
/* Lock the found filemon structure. */
filemon_filemon_lock(filemon);
copyinstr(uap->from, filemon->fname1,
sizeof(filemon->fname1), &done);
copyinstr(uap->to, filemon->fname2,
sizeof(filemon->fname2), &done);
len = snprintf(filemon->msgbufr,
sizeof(filemon->msgbufr), "M %d '%s' '%s'\n",
curproc->p_pid, filemon->fname1, filemon->fname2);
filemon_output(filemon, filemon->msgbufr, len);
/* Unlock the found filemon structure. */
filemon_filemon_unlock(filemon);
}
/* Release the read lock. */
filemon_unlock_read();
}
return (ret);
}
static int
filemon_wrapper_link(struct thread *td, struct link_args *uap)
{
int ret;
size_t done;
size_t len;
struct filemon *filemon;
if ((ret = sys_link(td, uap)) == 0) {
/* Grab a read lock on the filemon inuse list. */
filemon_lock_read();
if ((filemon = filemon_pid_check(curproc)) != NULL) {
/* Lock the found filemon structure. */
filemon_filemon_lock(filemon);
copyinstr(uap->path, filemon->fname1,
sizeof(filemon->fname1), &done);
copyinstr(uap->link, filemon->fname2,
sizeof(filemon->fname2), &done);
len = snprintf(filemon->msgbufr,
sizeof(filemon->msgbufr), "L %d '%s' '%s'\n",
curproc->p_pid, filemon->fname1, filemon->fname2);
filemon_output(filemon, filemon->msgbufr, len);
/* Unlock the found filemon structure. */
filemon_filemon_unlock(filemon);
}
/* Release the read lock. */
filemon_unlock_read();
}
return (ret);
}
static int
filemon_wrapper_symlink(struct thread *td, struct symlink_args *uap)
{
int ret;
size_t done;
size_t len;
struct filemon *filemon;
if ((ret = sys_symlink(td, uap)) == 0) {
/* Grab a read lock on the filemon inuse list. */
filemon_lock_read();
if ((filemon = filemon_pid_check(curproc)) != NULL) {
/* Lock the found filemon structure. */
filemon_filemon_lock(filemon);
copyinstr(uap->path, filemon->fname1,
sizeof(filemon->fname1), &done);
copyinstr(uap->link, filemon->fname2,
sizeof(filemon->fname2), &done);
len = snprintf(filemon->msgbufr,
sizeof(filemon->msgbufr), "L %d '%s' '%s'\n",
curproc->p_pid, filemon->fname1, filemon->fname2);
filemon_output(filemon, filemon->msgbufr, len);
/* Unlock the found filemon structure. */
filemon_filemon_unlock(filemon);
}
/* Release the read lock. */
filemon_unlock_read();
}
return (ret);
}
#ifdef FILEMON_HAS_LINKAT
static int
filemon_wrapper_linkat(struct thread *td, struct linkat_args *uap)
{
int ret;
size_t done;
size_t len;
struct filemon *filemon;
if ((ret = sys_linkat(td, uap)) == 0) {
/* Grab a read lock on the filemon inuse list. */
filemon_lock_read();
if ((filemon = filemon_pid_check(curproc)) != NULL) {
/* Lock the found filemon structure. */
filemon_filemon_lock(filemon);
copyinstr(uap->path1, filemon->fname1,
sizeof(filemon->fname1), &done);
copyinstr(uap->path2, filemon->fname2,
sizeof(filemon->fname2), &done);
len = snprintf(filemon->msgbufr,
sizeof(filemon->msgbufr), "L %d '%s' '%s'\n",
curproc->p_pid, filemon->fname1, filemon->fname2);
filemon_output(filemon, filemon->msgbufr, len);
/* Unlock the found filemon structure. */
filemon_filemon_unlock(filemon);
}
/* Release the read lock. */
filemon_unlock_read();
}
return (ret);
}
#endif
static int
filemon_wrapper_stat(struct thread *td, struct stat_args *uap)
{
int ret;
size_t done;
size_t len;
struct filemon *filemon;
if ((ret = sys_stat(td, uap)) == 0) {
/* Grab a read lock on the filemon inuse list. */
filemon_lock_read();
if ((filemon = filemon_pid_check(curproc)) != NULL) {
/* Lock the found filemon structure. */
filemon_filemon_lock(filemon);
copyinstr(uap->path, filemon->fname1,
sizeof(filemon->fname1), &done);
len = snprintf(filemon->msgbufr,
sizeof(filemon->msgbufr), "S %d %s\n",
curproc->p_pid, filemon->fname1);
filemon_output(filemon, filemon->msgbufr, len);
/* Unlock the found filemon structure. */
filemon_filemon_unlock(filemon);
}
/* Release the read lock. */
filemon_unlock_read();
}
return (ret);
}
#if defined(COMPAT_IA32) || defined(COMPAT_FREEBSD32) || defined(COMPAT_ARCH32)
static int
filemon_wrapper_freebsd32_stat(struct thread *td,
struct freebsd32_stat_args *uap)
{
int ret;
size_t done;
size_t len;
struct filemon *filemon;
if ((ret = freebsd32_stat(td, uap)) == 0) {
/* Grab a read lock on the filemon inuse list. */
filemon_lock_read();
if ((filemon = filemon_pid_check(curproc)) != NULL) {
/* Lock the found filemon structure. */
filemon_filemon_lock(filemon);
copyinstr(uap->path, filemon->fname1,
sizeof(filemon->fname1), &done);
len = snprintf(filemon->msgbufr,
sizeof(filemon->msgbufr), "S %d %s\n",
curproc->p_pid, filemon->fname1);
filemon_output(filemon, filemon->msgbufr, len);
/* Unlock the found filemon structure. */
filemon_filemon_unlock(filemon);
}
/* Release the read lock. */
filemon_unlock_read();
}
return (ret);
}
#endif
static void
filemon_wrapper_sys_exit(struct thread *td, struct sys_exit_args *uap)
{
size_t len;
struct filemon *filemon;
struct timeval now;
/* Get timestamp before locking. */
getmicrotime(&now);
/* Grab a read lock on the filemon inuse list. */
filemon_lock_read();
if ((filemon = filemon_pid_check(curproc)) != NULL) {
/* Lock the found filemon structure. */
filemon_filemon_lock(filemon);
len = snprintf(filemon->msgbufr, sizeof(filemon->msgbufr),
"X %d %d\n", curproc->p_pid, uap->rval);
filemon_output(filemon, filemon->msgbufr, len);
/* Check if the monitored process is about to exit. */
if (filemon->pid == curproc->p_pid) {
len = snprintf(filemon->msgbufr,
sizeof(filemon->msgbufr),
"# Stop %ju.%06ju\n# Bye bye\n",
(uintmax_t)now.tv_sec, (uintmax_t)now.tv_usec);
filemon_output(filemon, filemon->msgbufr, len);
}
/* Unlock the found filemon structure. */
filemon_filemon_unlock(filemon);
}
/* Release the read lock. */
filemon_unlock_read();
sys_sys_exit(td, uap);
}
static int
filemon_wrapper_unlink(struct thread *td, struct unlink_args *uap)
{
int ret;
size_t done;
size_t len;
struct filemon *filemon;
if ((ret = sys_unlink(td, uap)) == 0) {
/* Grab a read lock on the filemon inuse list. */
filemon_lock_read();
if ((filemon = filemon_pid_check(curproc)) != NULL) {
/* Lock the found filemon structure. */
filemon_filemon_lock(filemon);
copyinstr(uap->path, filemon->fname1,
sizeof(filemon->fname1), &done);
len = snprintf(filemon->msgbufr,
sizeof(filemon->msgbufr), "D %d %s\n",
curproc->p_pid, filemon->fname1);
filemon_output(filemon, filemon->msgbufr, len);
/* Unlock the found filemon structure. */
filemon_filemon_unlock(filemon);
}
/* Release the read lock. */
filemon_unlock_read();
}
return (ret);
}
static int
filemon_wrapper_vfork(struct thread *td, struct vfork_args *uap)
{
int ret;
size_t len;
struct filemon *filemon;
if ((ret = sys_vfork(td, uap)) == 0) {
/* Grab a read lock on the filemon inuse list. */
filemon_lock_read();
if ((filemon = filemon_pid_check(curproc)) != NULL) {
/* Lock the found filemon structure. */
filemon_filemon_lock(filemon);
len = snprintf(filemon->msgbufr,
sizeof(filemon->msgbufr), "F %d %ld\n",
curproc->p_pid, (long)curthread->td_retval[0]);
filemon_output(filemon, filemon->msgbufr, len);
/* Unlock the found filemon structure. */
filemon_filemon_unlock(filemon);
}
/* Release the read lock. */
filemon_unlock_read();
}
return (ret);
}
static void
filemon_wrapper_install(void)
{
#if defined(__i386__)
struct sysent *sv_table = elf32_freebsd_sysvec.sv_table;
#elif defined(__amd64__)
struct sysent *sv_table = elf64_freebsd_sysvec.sv_table;
#else
#error Machine type not supported
#endif
sv_table[SYS_chdir].sy_call = (sy_call_t *) filemon_wrapper_chdir;
sv_table[SYS_exit].sy_call = (sy_call_t *) filemon_wrapper_sys_exit;
sv_table[SYS_execve].sy_call = (sy_call_t *) filemon_wrapper_execve;
sv_table[SYS_fork].sy_call = (sy_call_t *) filemon_wrapper_fork;
sv_table[SYS_open].sy_call = (sy_call_t *) filemon_wrapper_open;
sv_table[SYS_rename].sy_call = (sy_call_t *) filemon_wrapper_rename;
sv_table[SYS_stat].sy_call = (sy_call_t *) filemon_wrapper_stat;
sv_table[SYS_unlink].sy_call = (sy_call_t *) filemon_wrapper_unlink;
sv_table[SYS_vfork].sy_call = (sy_call_t *) filemon_wrapper_vfork;
sv_table[SYS_link].sy_call = (sy_call_t *) filemon_wrapper_link;
sv_table[SYS_symlink].sy_call = (sy_call_t *) filemon_wrapper_symlink;
#ifdef FILEMON_HAS_LINKAT
sv_table[SYS_linkat].sy_call = (sy_call_t *) filemon_wrapper_linkat;
#endif
#if defined(COMPAT_IA32) || defined(COMPAT_FREEBSD32) || defined(COMPAT_ARCH32)
sv_table = ia32_freebsd_sysvec.sv_table;
sv_table[FREEBSD32_SYS_chdir].sy_call = (sy_call_t *) filemon_wrapper_chdir;
sv_table[FREEBSD32_SYS_exit].sy_call = (sy_call_t *) filemon_wrapper_sys_exit;
sv_table[FREEBSD32_SYS_freebsd32_execve].sy_call = (sy_call_t *) filemon_wrapper_freebsd32_execve;
sv_table[FREEBSD32_SYS_fork].sy_call = (sy_call_t *) filemon_wrapper_fork;
sv_table[FREEBSD32_SYS_open].sy_call = (sy_call_t *) filemon_wrapper_open;
sv_table[FREEBSD32_SYS_rename].sy_call = (sy_call_t *) filemon_wrapper_rename;
sv_table[FREEBSD32_SYS_freebsd32_stat].sy_call = (sy_call_t *) filemon_wrapper_freebsd32_stat;
sv_table[FREEBSD32_SYS_unlink].sy_call = (sy_call_t *) filemon_wrapper_unlink;
sv_table[FREEBSD32_SYS_vfork].sy_call = (sy_call_t *) filemon_wrapper_vfork;
sv_table[FREEBSD32_SYS_link].sy_call = (sy_call_t *) filemon_wrapper_link;
sv_table[FREEBSD32_SYS_symlink].sy_call = (sy_call_t *) filemon_wrapper_symlink;
#ifdef FILEMON_HAS_LINKAT
sv_table[FREEBSD32_SYS_linkat].sy_call = (sy_call_t *) filemon_wrapper_linkat;
#endif
#endif /* COMPAT_ARCH32 */
}
static void
filemon_wrapper_deinstall(void)
{
#if defined(__i386__)
struct sysent *sv_table = elf32_freebsd_sysvec.sv_table;
#elif defined(__amd64__)
struct sysent *sv_table = elf64_freebsd_sysvec.sv_table;
#else
#error Machine type not supported
#endif
sv_table[SYS_chdir].sy_call = (sy_call_t *)sys_chdir;
sv_table[SYS_exit].sy_call = (sy_call_t *)sys_sys_exit;
sv_table[SYS_execve].sy_call = (sy_call_t *)sys_execve;
sv_table[SYS_fork].sy_call = (sy_call_t *)sys_fork;
sv_table[SYS_open].sy_call = (sy_call_t *)sys_open;
sv_table[SYS_rename].sy_call = (sy_call_t *)sys_rename;
sv_table[SYS_stat].sy_call = (sy_call_t *)sys_stat;
sv_table[SYS_unlink].sy_call = (sy_call_t *)sys_unlink;
sv_table[SYS_vfork].sy_call = (sy_call_t *)sys_vfork;
sv_table[SYS_link].sy_call = (sy_call_t *)sys_link;
sv_table[SYS_symlink].sy_call = (sy_call_t *)sys_symlink;
#ifdef FILEMON_HAS_LINKAT
sv_table[SYS_linkat].sy_call = (sy_call_t *)sys_linkat;
#endif
#if defined(COMPAT_IA32) || defined(COMPAT_FREEBSD32) || defined(COMPAT_ARCH32)
sv_table = ia32_freebsd_sysvec.sv_table;
sv_table[FREEBSD32_SYS_chdir].sy_call = (sy_call_t *)sys_chdir;
sv_table[FREEBSD32_SYS_exit].sy_call = (sy_call_t *)sys_sys_exit;
sv_table[FREEBSD32_SYS_freebsd32_execve].sy_call = (sy_call_t *)freebsd32_execve;
sv_table[FREEBSD32_SYS_fork].sy_call = (sy_call_t *)sys_fork;
sv_table[FREEBSD32_SYS_open].sy_call = (sy_call_t *)sys_open;
sv_table[FREEBSD32_SYS_rename].sy_call = (sy_call_t *)sys_rename;
sv_table[FREEBSD32_SYS_freebsd32_stat].sy_call = (sy_call_t *)freebsd32_stat;
sv_table[FREEBSD32_SYS_unlink].sy_call = (sy_call_t *)sys_unlink;
sv_table[FREEBSD32_SYS_vfork].sy_call = (sy_call_t *)sys_vfork;
sv_table[FREEBSD32_SYS_link].sy_call = (sy_call_t *)sys_link;
sv_table[FREEBSD32_SYS_symlink].sy_call = (sy_call_t *)sys_symlink;
#ifdef FILEMON_HAS_LINKAT
sv_table[FREEBSD32_SYS_linkat].sy_call = (sy_call_t *)sys_linkat;
#endif
#endif /* COMPAT_ARCH32 */
}