NetBSD/sys/dev/verified_exec.c

254 lines
7.6 KiB
C

/* $NetBSD: verified_exec.c,v 1.1 2002/10/29 12:31:22 blymn Exp $ */
/*-
* Copyright (c) 1998-1999 Brett Lymn
* (blymn@baea.com.au, brett_lymn@yahoo.com.au)
* All rights reserved.
*
* This code has been donated to The NetBSD Foundation by the Author.
*
* 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. The name of the author may not be used to endorse or promote products
* derived from this software withough specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/errno.h>
#include <sys/verified_exec.h>
#include <sys/buf.h>
#include <sys/malloc.h>
#include <sys/ioctl.h>
#include <sys/device.h>
#include <sys/conf.h>
#include <sys/lock.h>
#include <sys/queue.h>
#include <sys/vnode.h>
#include <sys/fcntl.h>
#include <sys/namei.h>
struct verified_exec_softc {
struct device veriexec_dev;
};
const struct cdevsw verifiedexec_cdevsw = {
verifiedexecopen, verifiedexecclose, noread, nowrite,
verifiedexecioctl, nostop, notty, nopoll, nommap, nokqfilter,
};
/* internal structures */
LIST_HEAD(veriexec_devhead, veriexec_dev_list) veriexec_dev_head;
/*LIST_HEAD(veriexec_file_devhead, veriexec_dev_list) veriexec_file_dev_head;*/
struct veriexec_devhead veriexec_file_dev_head;
/* Autoconfiguration glue */
void verifiedexecattach(struct device *parent, struct device *self,
void *aux);
int verifiedexecopen(dev_t dev, int flags, int fmt, struct proc *p);
int verifiedexecclose(dev_t dev, int flags, int fmt, struct proc *p);
int verifiedexecioctl(dev_t dev, u_long cmd, caddr_t data, int flags,
struct proc *p);
void add_veriexec_inode(struct veriexec_dev_list *list, unsigned long inode,
unsigned char fingerprint[MAXFINGERPRINTLEN],
unsigned char type, unsigned char fp_type);
struct veriexec_dev_list *find_veriexec_dev(unsigned long dev,
struct veriexec_devhead *head);
/*
* Attach for autoconfig to find. Initialise the lists and return...
*/
void
verifiedexecattach(struct device *parent, struct device *self, void *aux)
{
LIST_INIT(&veriexec_dev_head);
LIST_INIT(&veriexec_file_dev_head);
}
int
verifiedexecopen(dev_t dev, int flags, int fmt, struct proc *p)
{
return 0;
}
int
verifiedexecclose(dev_t dev, int flags, int fmt, struct proc *p)
{
#ifdef VERIFIED_EXEC_DEBUG_VERBOSE
struct veriexec_dev_list *lp;
struct veriexec_inode_list *ip;
printf("Loaded exec fingerprint list is:\n");
for (lp = LIST_FIRST(&veriexec_dev_head); lp != NULL;
lp = LIST_NEXT(lp, entries)) {
for (ip = LIST_FIRST(&(lp->inode_head)); ip != NULL;
ip = LIST_NEXT(ip, entries)) {
printf("Got loaded fingerprint for dev %lu, inode %lu\n",
lp->id, ip->inode);
}
}
printf("\n\nLoaded file fingerprint list is:\n");
for (lp = LIST_FIRST(&veriexec_file_dev_head); lp != NULL;
lp = LIST_NEXT(lp, entries)) {
for (ip = LIST_FIRST(&(lp->inode_head)); ip != NULL;
ip = LIST_NEXT(ip, entries)) {
printf("Got loaded fingerprint for dev %lu, inode %lu\n",
lp->id, ip->inode);
}
}
#endif
return 0;
}
/*
* Search the list of devices looking for the one given. If it is not
* in the list then add it.
*/
struct veriexec_dev_list *
find_veriexec_dev(unsigned long dev, struct veriexec_devhead *head)
{
struct veriexec_dev_list *lp;
for (lp = LIST_FIRST(head); lp != NULL;
lp = LIST_NEXT(lp, entries))
if (lp->id == dev) break;
if (lp == NULL) {
/* if pointer is null then entry not there, add a new one */
MALLOC(lp, struct veriexec_dev_list *,
sizeof(struct veriexec_dev_list), M_TEMP, M_WAITOK);
LIST_INIT(&(lp->inode_head));
lp->id = dev;
LIST_INSERT_HEAD(head, lp, entries);
}
return lp;
}
/*
* Add a file's inode and fingerprint to the list of inodes attached
* to the device id. Only add the entry if it is not already on the
* list.
*/
void
add_veriexec_inode(struct veriexec_dev_list *list, unsigned long inode,
unsigned char fingerprint[MAXFINGERPRINTLEN],
unsigned char type, unsigned char fp_type)
{
struct veriexec_inode_list *ip;
for (ip = LIST_FIRST(&(list->inode_head)); ip != NULL;
ip = LIST_NEXT(ip, entries))
/* check for a dupe inode in the list, skip if an entry
* exists for this inode except for when the type is
* VERIEXEC_INDIRECT, always set the type when it is so
* we don't get a hole caused by conflicting types on
* hardlinked files. XXX maybe we should validate
* fingerprint is same and complain if it is not...
*/
if (ip->inode == inode) {
if (type == VERIEXEC_INDIRECT)
ip->type = type;
return;
}
MALLOC(ip, struct veriexec_inode_list *, sizeof(struct veriexec_inode_list),
M_TEMP, M_WAITOK);
ip->type = type;
ip->fp_type = fp_type;
ip->inode = inode;
memcpy(ip->fingerprint, fingerprint, sizeof(ip->fingerprint));
LIST_INSERT_HEAD(&(list->inode_head), ip, entries);
}
/*
* Handle the ioctl for the device
*/
int
verifiedexecioctl(dev_t dev, u_long cmd, caddr_t data, int flags,
struct proc *p)
{
int error = 0;
struct verified_exec_params *params = (struct verified_exec_params *)data;
struct nameidata nid;
struct vattr vattr;
struct veriexec_dev_list *dlp;
#ifdef VERIFIED_EXEC_DEBUG
printf("veriexec_ioctl: got cmd 0x%lx for file %s\n", cmd, params->file);
#endif
switch (cmd) {
case VERIEXECLOAD:
if (securelevel > 0) {
/* don't allow updates when secure */
error = EPERM;
} else {
/*
* Get the attributes for the file name passed
* stash the file's device id and inode number
* along with it's fingerprint in a list for
* exec to use later.
*/
NDINIT(&nid, LOOKUP, FOLLOW, UIO_USERSPACE,
params->file, p);
if ((error = vn_open(&nid, FREAD, 0)) != 0) {
return(error);
}
error = VOP_GETATTR(nid.ni_vp, &vattr, p->p_ucred, p);
if (error) {
nid.ni_vp->fp_status = FINGERPRINT_INVALID;
VOP_UNLOCK(nid.ni_vp, 0);
(void) vn_close(nid.ni_vp, FREAD,
p->p_ucred, p);
return(error);
}
/* invalidate the node fingerprint status
* which will have been set in the vn_open
* and would always be FINGERPRINT_NOTFOUND
*/
nid.ni_vp->fp_status = FINGERPRINT_INVALID;
VOP_UNLOCK(nid.ni_vp, 0);
(void) vn_close(nid.ni_vp, FREAD, p->p_ucred, p);
/* vattr.va_fsid = dev, vattr.va_fileid = inode */
if (params->type == VERIEXEC_FILE) {
dlp = find_veriexec_dev(vattr.va_fsid,
&veriexec_file_dev_head);
} else {
dlp = find_veriexec_dev(vattr.va_fsid,
&veriexec_dev_head);
}
add_veriexec_inode(dlp, vattr.va_fileid,
params->fingerprint, params->type,
params->fp_type);
}
break;
default:
error = ENODEV;
}
return (error);
}