vscan_svc.c revision d3d50737e566cade9a08d73d2af95105ac7cd960
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2009 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#include <sys/stat.h>
#include <sys/ddi.h>
#include <sys/sunddi.h>
#include <sys/time.h>
#include <sys/varargs.h>
#include <sys/conf.h>
#include <sys/modctl.h>
#include <sys/cmn_err.h>
#include <sys/vnode.h>
#include <fs/fs_subr.h>
#include <sys/types.h>
#include <sys/file.h>
#include <sys/disp.h>
#include <sys/sdt.h>
#include <sys/cred.h>
#include <sys/list.h>
#include <sys/vscan.h>
#define VS_REQ_MAGIC 0x52515354 /* 'RQST' */
#define VS_REQS_DEFAULT 20000 /* pending scan requests - reql */
#define VS_NODES_DEFAULT 128 /* concurrent file scans */
#define VS_WORKERS_DEFAULT 32 /* worker threads */
#define VS_SCANWAIT_DEFAULT 15*60 /* seconds to wait for scan result */
#define VS_REQL_HANDLER_TIMEOUT 30
#define VS_EXT_RECURSE_DEPTH 8
/* access derived from scan result (VS_STATUS_XXX) and file attributes */
#define VS_ACCESS_UNDEFINED 0
#define VS_ACCESS_ALLOW 1 /* return 0 */
#define VS_ACCESS_DENY 2 /* return EACCES */
#define tolower(C) (((C) >= 'A' && (C) <= 'Z') ? (C) - 'A' + 'a' : (C))
#define offsetof(s, m) (size_t)(&(((s *)0)->m))
/* global variables - tunable via /etc/system */
uint32_t vs_reqs_max = VS_REQS_DEFAULT; /* max scan requests */
uint32_t vs_nodes_max = VS_NODES_DEFAULT; /* max in-progress scan requests */
uint32_t vs_workers = VS_WORKERS_DEFAULT; /* max workers send reqs to vscand */
uint32_t vs_scan_wait = VS_SCANWAIT_DEFAULT; /* secs to wait for scan result */
/*
* vscan_svc_state
*
* +-----------------+
* | VS_SVC_UNCONFIG |
* +-----------------+
* | ^
* | svc_init | svc_fini
* v |
* +-----------------+
* | VS_SVC_IDLE |<----|
* +-----------------+ |
* | |
* | svc_enable |
* |<----------------| |
* v | |
* +-----------------+ | |
* | VS_SVC_ENABLED |--| |
* +-----------------+ |
* | |
* | svc_disable | handler thread exit,
* v | all requests complete
* +-----------------+ |
* | VS_SVC_DISABLED |-----|
* +-----------------+
*
* svc_enable may occur when we are already in the ENABLED
* state if vscand has exited without clean shutdown and
* then reconnected within the delayed disable time period
* (vs_reconnect_timeout) - see vscan_drv
*/
typedef enum {
VS_SVC_UNCONFIG,
VS_SVC_IDLE,
VS_SVC_ENABLED, /* service enabled and registered */
VS_SVC_DISABLED /* service disabled and nunregistered */
} vscan_svc_state_t;
static vscan_svc_state_t vscan_svc_state = VS_SVC_UNCONFIG;
/*
* vscan_svc_req_state
*
* When a scan request is received from the file system it is
* identified in or inserted into the vscan_svc_reql (INIT).
* If the request is asynchronous 0 is then returned to the caller.
* If the request is synchronous the req's refcnt is incremented
* and the caller waits for the request to complete.
* The refcnt is also incremented when the request is inserted
* in vscan_svc_nodes, and decremented on scan_complete.
*
* vscan_svc_handler processes requests from the request list,
* inserting them into vscan_svc_nodes and the task queue (QUEUED).
* When the task queue call back (vscan_svc_do_scan) is invoked
* the request transitions to IN_PROGRESS state. If the request
* is sucessfully sent to vscand (door_call) and the door response
* is SCANNING then the scan result will be received asynchronously.
* Although unusual, it is possible that the async response is
* received before the door call returns (hence the ASYNC_COMPLETE
* state).
* When the result has been determined / received,
* vscan_svc_scan_complete is invoked to transition the request to
* COMPLETE state, decrement refcnt and signal all waiting callers.
* When the last waiting caller has processed the result (refcnt == 0)
* the request is removed from vscan_svc_reql and vscan_svc_nodes
* and deleted.
*
* | ^
* | reql_insert | refcnt == 0
* v | (delete)
* +------------------------+ +---------------------+
* | VS_SVC_REQ_INIT | -----DISABLE----> | VS_SVC_REQ_COMPLETE |
* +------------------------+ +---------------------+
* | ^
* | insert_req, tq_dispatch |
* v |
* +------------------------+ |
* | VS_SVC_REQ_QUEUED | scan_complete
* +------------------------+ |
* | |
* | tq_callback (do_scan) |
* | |
* v scan not req'd, error, |
* +------------------------+ or door_result != SCANNING |
* | VS_SVC_REQ_IN_PROGRESS |----------------->-------------|
* +------------------------+ |
* | | |
* | | door_result == SCANNING |
* | v |
* | +---------------------------+ async result |
* | | VS_SVC_REQ_SCANNING |-------->---------|
* | +---------------------------+ |
* | |
* | async result |
* v |
* +---------------------------+ door_result = SCANNING |
* | VS_SVC_REQ_ASYNC_COMPLETE |-------->------------------|
* +---------------------------+
*/
typedef enum {
VS_SVC_REQ_INIT,
VS_SVC_REQ_QUEUED,
VS_SVC_REQ_IN_PROGRESS,
VS_SVC_REQ_SCANNING,
VS_SVC_REQ_ASYNC_COMPLETE,
VS_SVC_REQ_COMPLETE
} vscan_svc_req_state_t;
/*
* vscan_svc_reql - the list of pending and in-progress scan requests
*/
typedef struct vscan_req {
uint32_t vsr_magic; /* VS_REQ_MAGIC */
list_node_t vsr_lnode;
vnode_t *vsr_vp;
uint32_t vsr_idx; /* vscan_svc_nodes index */
uint32_t vsr_seqnum; /* unigue request id */
uint32_t vsr_refcnt;
kcondvar_t vsr_cv;
vscan_svc_req_state_t vsr_state;
} vscan_req_t;
static list_t vscan_svc_reql;
/*
* vscan_svc_nodes - table of files being scanned
*
* The index into this table is passed in the door call to
* vscand. vscand uses the idx to determine which minor node
* to open to read the file data. Within the kernel driver
* the minor device number can thus be used to identify the
* table index to get the appropriate vnode.
*
* Instance 0 is reserved for the daemon/driver control
* interface: enable/configure/disable
*/
typedef struct vscan_svc_node {
vscan_req_t *vsn_req;
uint8_t vsn_quarantined;
uint8_t vsn_modified;
uint64_t vsn_size;
timestruc_t vsn_mtime;
vs_scanstamp_t vsn_scanstamp;
uint32_t vsn_result;
uint32_t vsn_access;
} vscan_svc_node_t;
static vscan_svc_node_t *vscan_svc_nodes;
static int vscan_svc_nodes_sz;
/* vscan_svc_taskq - queue of requests waiting to be sent to vscand */
static taskq_t *vscan_svc_taskq = NULL;
/* counts of entries in vscan_svc_reql, vscan_svc_nodes & vscan_svc_taskq */
typedef struct {
uint32_t vsc_reql;
uint32_t vsc_node;
uint32_t vsc_tq;
} vscan_svc_counts_t;
static vscan_svc_counts_t vscan_svc_counts;
/*
* vscan_svc_mutex protects the data pertaining to scan requests:
* request list - vscan_svc_reql
* node table - vscan_svc_nodes
*/
static kmutex_t vscan_svc_mutex;
/* unique request id for vscand request/response correlation */
static uint32_t vscan_svc_seqnum = 0;
/*
* vscan_svc_cfg_mutex protects the configuration data:
* vscan_svc_config, vscan_svc_types
*/
static kmutex_t vscan_svc_cfg_mutex;
/* configuration data - for virus scan exemption */
static vs_config_t vscan_svc_config;
static char *vscan_svc_types[VS_TYPES_MAX];
/* thread to insert reql entries into vscan_svc_nodes & vscan_svc_taskq */
static kthread_t *vscan_svc_reql_thread;
static kcondvar_t vscan_svc_reql_cv;
static vscan_req_t *vscan_svc_reql_next; /* next pending scan request */
/* local functions */
int vscan_svc_scan_file(vnode_t *, cred_t *, int);
static void vscan_svc_taskq_callback(void *);
static int vscan_svc_exempt_file(vnode_t *, boolean_t *);
static int vscan_svc_exempt_filetype(char *);
static int vscan_svc_match_ext(char *, char *, int);
static void vscan_svc_do_scan(vscan_req_t *);
static vs_scan_req_t *vscan_svc_populate_req(int);
static void vscan_svc_process_scan_result(int);
static void vscan_svc_scan_complete(vscan_req_t *);
static void vscan_svc_delete_req(vscan_req_t *);
static int vscan_svc_insert_req(vscan_req_t *);
static void vscan_svc_remove_req(int);
static vscan_req_t *vscan_svc_reql_find(vnode_t *);
static vscan_req_t *vscan_svc_reql_insert(vnode_t *);
static void vscan_svc_reql_remove(vscan_req_t *);
static int vscan_svc_getattr(int);
static int vscan_svc_setattr(int, int);
/* thread to insert reql entries into vscan_svc_nodes & vscan_svc_taskq */
static void vscan_svc_reql_handler(void);
/*
* vscan_svc_init
*/
int
vscan_svc_init()
{
if (vscan_svc_state != VS_SVC_UNCONFIG) {
DTRACE_PROBE1(vscan__svc__state__violation,
int, vscan_svc_state);
return (-1);
}
mutex_init(&vscan_svc_mutex, NULL, MUTEX_DEFAULT, NULL);
mutex_init(&vscan_svc_cfg_mutex, NULL, MUTEX_DEFAULT, NULL);
cv_init(&vscan_svc_reql_cv, NULL, CV_DEFAULT, NULL);
vscan_svc_nodes_sz = sizeof (vscan_svc_node_t) * (vs_nodes_max + 1);
vscan_svc_nodes = kmem_zalloc(vscan_svc_nodes_sz, KM_SLEEP);
vscan_svc_counts.vsc_reql = 0;
vscan_svc_counts.vsc_node = 0;
vscan_svc_counts.vsc_tq = 0;
vscan_svc_state = VS_SVC_IDLE;
return (0);
}
/*
* vscan_svc_fini
*/
void
vscan_svc_fini()
{
if (vscan_svc_state != VS_SVC_IDLE) {
DTRACE_PROBE1(vscan__svc__state__violation,
int, vscan_svc_state);
return;
}
kmem_free(vscan_svc_nodes, vscan_svc_nodes_sz);
cv_destroy(&vscan_svc_reql_cv);
mutex_destroy(&vscan_svc_mutex);
mutex_destroy(&vscan_svc_cfg_mutex);
vscan_svc_state = VS_SVC_UNCONFIG;
}
/*
* vscan_svc_enable
*/
int
vscan_svc_enable(void)
{
mutex_enter(&vscan_svc_mutex);
switch (vscan_svc_state) {
case VS_SVC_ENABLED:
/*
* it's possible (and okay) for vscan_svc_enable to be
* called when already enabled if vscand reconnects
* during a delayed disable
*/
break;
case VS_SVC_IDLE:
list_create(&vscan_svc_reql, sizeof (vscan_req_t),
offsetof(vscan_req_t, vsr_lnode));
vscan_svc_reql_next = list_head(&vscan_svc_reql);
vscan_svc_taskq = taskq_create("vscan_taskq", vs_workers,
MINCLSYSPRI, 1, INT_MAX, TASKQ_DYNAMIC);
ASSERT(vscan_svc_taskq != NULL);
vscan_svc_reql_thread = thread_create(NULL, 0,
vscan_svc_reql_handler, 0, 0, &p0, TS_RUN, MINCLSYSPRI);
ASSERT(vscan_svc_reql_thread != NULL);
/* ready to start processing requests */
vscan_svc_state = VS_SVC_ENABLED;
fs_vscan_register(vscan_svc_scan_file);
break;
default:
DTRACE_PROBE1(vscan__svc__state__violation,
int, vscan_svc_state);
return (-1);
}
mutex_exit(&vscan_svc_mutex);
return (0);
}
/*
* vscan_svc_disable
*
* Resources allocated during vscan_svc_enable are free'd by
* the handler thread immediately prior to exiting
*/
void
vscan_svc_disable(void)
{
mutex_enter(&vscan_svc_mutex);
switch (vscan_svc_state) {
case VS_SVC_ENABLED:
fs_vscan_register(NULL);
vscan_svc_state = VS_SVC_DISABLED;
cv_signal(&vscan_svc_reql_cv); /* wake handler thread */
break;
default:
DTRACE_PROBE1(vscan__svc__state__violation, int,
vscan_svc_state);
}
mutex_exit(&vscan_svc_mutex);
}
/*
* vscan_svc_in_use
*/
boolean_t
vscan_svc_in_use()
{
boolean_t in_use;
mutex_enter(&vscan_svc_mutex);
switch (vscan_svc_state) {
case VS_SVC_IDLE:
case VS_SVC_UNCONFIG:
in_use = B_FALSE;
break;
default:
in_use = B_TRUE;
break;
}
mutex_exit(&vscan_svc_mutex);
return (in_use);
}
/*
* vscan_svc_get_vnode
*
* Get the file vnode indexed by idx.
*/
vnode_t *
vscan_svc_get_vnode(int idx)
{
vnode_t *vp = NULL;
ASSERT(idx > 0);
ASSERT(idx <= vs_nodes_max);
mutex_enter(&vscan_svc_mutex);
if (vscan_svc_nodes[idx].vsn_req)
vp = vscan_svc_nodes[idx].vsn_req->vsr_vp;
mutex_exit(&vscan_svc_mutex);
return (vp);
}
/*
* vscan_svc_scan_file
*
* This function is the entry point for the file system to
* request that a file be virus scanned.
*/
int
vscan_svc_scan_file(vnode_t *vp, cred_t *cr, int async)
{
int access;
vscan_req_t *req;
boolean_t allow;
clock_t timeout, time_left;
if ((vp == NULL) || (vp->v_path == NULL) || cr == NULL)
return (0);
DTRACE_PROBE2(vscan__scan__file, char *, vp->v_path, int, async);
/* check if size or type exempts file from scanning */
if (vscan_svc_exempt_file(vp, &allow)) {
if ((allow == B_TRUE) || (async != 0))
return (0);
return (EACCES);
}
mutex_enter(&vscan_svc_mutex);
if (vscan_svc_state != VS_SVC_ENABLED) {
DTRACE_PROBE1(vscan__svc__state__violation,
int, vscan_svc_state);
mutex_exit(&vscan_svc_mutex);
return (0);
}
/* insert (or find) request in list */
if ((req = vscan_svc_reql_insert(vp)) == NULL) {
mutex_exit(&vscan_svc_mutex);
cmn_err(CE_WARN, "Virus scan request list full");
return ((async != 0) ? 0 : EACCES);
}
/* asynchronous request: return 0 */
if (async) {
mutex_exit(&vscan_svc_mutex);
return (0);
}
/* synchronous scan request: wait for result */
++(req->vsr_refcnt);
time_left = SEC_TO_TICK(vs_scan_wait);
while ((time_left > 0) && (req->vsr_state != VS_SVC_REQ_COMPLETE)) {
timeout = time_left;
time_left = cv_reltimedwait_sig(&(req->vsr_cv),
&vscan_svc_mutex, timeout, TR_CLOCK_TICK);
}
if (time_left == -1) {
cmn_err(CE_WARN, "Virus scan request timeout %s (%d) \n",
vp->v_path, req->vsr_seqnum);
DTRACE_PROBE1(vscan__scan__timeout, vscan_req_t *, req);
}
ASSERT(req->vsr_magic == VS_REQ_MAGIC);
if (vscan_svc_state == VS_SVC_DISABLED)
access = VS_ACCESS_ALLOW;
else if (req->vsr_idx == 0)
access = VS_ACCESS_DENY;
else
access = vscan_svc_nodes[req->vsr_idx].vsn_access;
if ((--req->vsr_refcnt) == 0)
vscan_svc_delete_req(req);
mutex_exit(&vscan_svc_mutex);
return ((access == VS_ACCESS_ALLOW) ? 0 : EACCES);
}
/*
* vscan_svc_reql_handler
*
* inserts scan requests (from vscan_svc_reql) into
* vscan_svc_nodes and vscan_svc_taskq
*/
static void
vscan_svc_reql_handler(void)
{
vscan_req_t *req, *next;
for (;;) {
mutex_enter(&vscan_svc_mutex);
if ((vscan_svc_state == VS_SVC_DISABLED) &&
(vscan_svc_counts.vsc_reql == 0)) {
/* free resources allocated durining enable */
taskq_destroy(vscan_svc_taskq);
vscan_svc_taskq = NULL;
list_destroy(&vscan_svc_reql);
vscan_svc_state = VS_SVC_IDLE;
mutex_exit(&vscan_svc_mutex);
return;
}
/*
* If disabled, scan_complete any pending requests.
* Otherwise insert pending requests into vscan_svc_nodes
* and vscan_svc_taskq. If no slots are available in
* vscan_svc_nodes break loop and wait for one
*/
req = vscan_svc_reql_next;
while (req != NULL) {
ASSERT(req->vsr_magic == VS_REQ_MAGIC);
next = list_next(&vscan_svc_reql, req);
if (vscan_svc_state == VS_SVC_DISABLED) {
vscan_svc_scan_complete(req);
} else {
/* insert request into vscan_svc_nodes */
if (vscan_svc_insert_req(req) == -1)
break;
/* add the scan request into the taskq */
(void) taskq_dispatch(vscan_svc_taskq,
vscan_svc_taskq_callback,
(void *)req, TQ_SLEEP);
++(vscan_svc_counts.vsc_tq);
req->vsr_state = VS_SVC_REQ_QUEUED;
}
req = next;
}
vscan_svc_reql_next = req;
DTRACE_PROBE2(vscan__req__counts, char *, "handler wait",
vscan_svc_counts_t *, &vscan_svc_counts);
(void) cv_reltimedwait(&vscan_svc_reql_cv, &vscan_svc_mutex,
SEC_TO_TICK(VS_REQL_HANDLER_TIMEOUT), TR_CLOCK_TICK);
DTRACE_PROBE2(vscan__req__counts, char *, "handler wake",
vscan_svc_counts_t *, &vscan_svc_counts);
mutex_exit(&vscan_svc_mutex);
}
}
static void
vscan_svc_taskq_callback(void *data)
{
vscan_req_t *req;
mutex_enter(&vscan_svc_mutex);
req = (vscan_req_t *)data;
ASSERT(req->vsr_magic == VS_REQ_MAGIC);
vscan_svc_do_scan(req);
if (req->vsr_state != VS_SVC_REQ_SCANNING)
vscan_svc_scan_complete(req);
--(vscan_svc_counts.vsc_tq);
mutex_exit(&vscan_svc_mutex);
}
/*
* vscan_svc_do_scan
*
* Note: To avoid potential deadlock it is important that
* vscan_svc_mutex is not held during the call to
* vscan_drv_create_note. vscan_drv_create_note enters
* the vscan_drv_mutex and it is possible that a thread
* holding that mutex could be waiting for vscan_svc_mutex.
*/
static void
vscan_svc_do_scan(vscan_req_t *req)
{
int idx, result;
vscan_svc_node_t *node;
vs_scan_req_t *door_req;
ASSERT(MUTEX_HELD(&vscan_svc_mutex));
idx = req->vsr_idx;
node = &vscan_svc_nodes[idx];
req->vsr_state = VS_SVC_REQ_IN_PROGRESS;
/* if vscan not enabled (shutting down), allow ACCESS */
if (vscan_svc_state != VS_SVC_ENABLED) {
node->vsn_access = VS_ACCESS_ALLOW;
return;
}
if (vscan_svc_getattr(idx) != 0) {
cmn_err(CE_WARN, "Can't access xattr for %s\n",
req->vsr_vp->v_path);
node->vsn_access = VS_ACCESS_DENY;
return;
}
/* valid scan_req ptr guaranteed */
door_req = vscan_svc_populate_req(idx);
/* free up mutex around create node and door call */
mutex_exit(&vscan_svc_mutex);
if (vscan_drv_create_node(idx) != B_TRUE)
result = VS_STATUS_ERROR;
else
result = vscan_door_scan_file(door_req);
kmem_free(door_req, sizeof (vs_scan_req_t));
mutex_enter(&vscan_svc_mutex);
if (result != VS_STATUS_SCANNING) {
vscan_svc_nodes[idx].vsn_result = result;
vscan_svc_process_scan_result(idx);
} else { /* async response */
if (req->vsr_state == VS_SVC_REQ_IN_PROGRESS)
req->vsr_state = VS_SVC_REQ_SCANNING;
}
}
/*
* vscan_svc_populate_req
*
* Allocate a scan request to be sent to vscand, populating it
* from the data in vscan_svc_nodes[idx].
*
* Returns: scan request object
*/
static vs_scan_req_t *
vscan_svc_populate_req(int idx)
{
vs_scan_req_t *scan_req;
vscan_req_t *req;
vscan_svc_node_t *node;
ASSERT(MUTEX_HELD(&vscan_svc_mutex));
node = &vscan_svc_nodes[idx];
req = node->vsn_req;
scan_req = kmem_zalloc(sizeof (vs_scan_req_t), KM_SLEEP);
scan_req->vsr_idx = idx;
scan_req->vsr_seqnum = req->vsr_seqnum;
(void) strncpy(scan_req->vsr_path, req->vsr_vp->v_path, MAXPATHLEN);
scan_req->vsr_size = node->vsn_size;
scan_req->vsr_modified = node->vsn_modified;
scan_req->vsr_quarantined = node->vsn_quarantined;
scan_req->vsr_flags = 0;
(void) strncpy(scan_req->vsr_scanstamp,
node->vsn_scanstamp, sizeof (vs_scanstamp_t));
return (scan_req);
}
/*
* vscan_svc_scan_complete
*/
static void
vscan_svc_scan_complete(vscan_req_t *req)
{
ASSERT(MUTEX_HELD(&vscan_svc_mutex));
ASSERT(req != NULL);
req->vsr_state = VS_SVC_REQ_COMPLETE;
if ((--req->vsr_refcnt) == 0)
vscan_svc_delete_req(req);
else
cv_broadcast(&(req->vsr_cv));
}
/*
* vscan_svc_delete_req
*/
static void
vscan_svc_delete_req(vscan_req_t *req)
{
int idx;
ASSERT(MUTEX_HELD(&vscan_svc_mutex));
ASSERT(req != NULL);
ASSERT(req->vsr_refcnt == 0);
ASSERT(req->vsr_state == VS_SVC_REQ_COMPLETE);
if ((idx = req->vsr_idx) != 0)
vscan_svc_remove_req(idx);
vscan_svc_reql_remove(req);
cv_signal(&vscan_svc_reql_cv);
}
/*
* vscan_svc_scan_result
*
* Invoked from vscan_drv.c on receipt of an ioctl containing
* an async scan result (VS_DRV_IOCTL_RESULT)
* If the vsr_seqnum in the response does not match that in the
* vscan_svc_nodes entry the result is discarded.
*/
void
vscan_svc_scan_result(vs_scan_rsp_t *scan_rsp)
{
vscan_req_t *req;
vscan_svc_node_t *node;
mutex_enter(&vscan_svc_mutex);
node = &vscan_svc_nodes[scan_rsp->vsr_idx];
if ((req = node->vsn_req) == NULL) {
mutex_exit(&vscan_svc_mutex);
return;
}
ASSERT(req->vsr_magic == VS_REQ_MAGIC);
if (scan_rsp->vsr_seqnum != req->vsr_seqnum) {
mutex_exit(&vscan_svc_mutex);
return;
}
node->vsn_result = scan_rsp->vsr_result;
(void) strncpy(node->vsn_scanstamp,
scan_rsp->vsr_scanstamp, sizeof (vs_scanstamp_t));
vscan_svc_process_scan_result(scan_rsp->vsr_idx);
if (node->vsn_req->vsr_state == VS_SVC_REQ_SCANNING)
vscan_svc_scan_complete(node->vsn_req);
else
node->vsn_req->vsr_state = VS_SVC_REQ_ASYNC_COMPLETE;
mutex_exit(&vscan_svc_mutex);
}
/*
* vscan_svc_scan_abort
*
* Abort in-progress scan requests.
*/
void
vscan_svc_scan_abort()
{
int idx;
vscan_req_t *req;
mutex_enter(&vscan_svc_mutex);
for (idx = 1; idx <= vs_nodes_max; idx++) {
if ((req = vscan_svc_nodes[idx].vsn_req) == NULL)
continue;
ASSERT(req->vsr_magic == VS_REQ_MAGIC);
if (req->vsr_state == VS_SVC_REQ_SCANNING) {
DTRACE_PROBE1(vscan__abort, vscan_req_t *, req);
vscan_svc_process_scan_result(idx);
vscan_svc_scan_complete(req);
}
}
mutex_exit(&vscan_svc_mutex);
}
/*
* vscan_svc_process_scan_result
*
* Sets vsn_access and updates file attributes based on vsn_result,
* as follows:
*
* VS_STATUS_INFECTED
* deny access, set quarantine attribute, clear scanstamp
* VS_STATUS_CLEAN
* allow access, set scanstamp,
* if file not modified since scan initiated, clear modified attribute
* VS_STATUS_NO_SCAN
* deny access if file quarantined, otherwise allow access
* VS_STATUS_UNDEFINED, VS_STATUS_ERROR
* deny access if file quarantined, modified or no scanstamp
* otherwise, allow access
*/
static void
vscan_svc_process_scan_result(int idx)
{
struct vattr attr;
vnode_t *vp;
timestruc_t *mtime;
vscan_svc_node_t *node;
ASSERT(MUTEX_HELD(&vscan_svc_mutex));
node = &vscan_svc_nodes[idx];
switch (node->vsn_result) {
case VS_STATUS_INFECTED:
node->vsn_access = VS_ACCESS_DENY;
node->vsn_quarantined = 1;
node->vsn_scanstamp[0] = '\0';
(void) vscan_svc_setattr(idx,
XAT_AV_QUARANTINED | XAT_AV_SCANSTAMP);
break;
case VS_STATUS_CLEAN:
node->vsn_access = VS_ACCESS_ALLOW;
/* if mtime has changed, don't clear the modified attribute */
vp = node->vsn_req->vsr_vp;
mtime = &(node->vsn_mtime);
attr.va_mask = AT_MTIME;
if ((VOP_GETATTR(vp, &attr, 0, kcred, NULL) != 0) ||
(mtime->tv_sec != attr.va_mtime.tv_sec) ||
(mtime->tv_nsec != attr.va_mtime.tv_nsec)) {
DTRACE_PROBE1(vscan__mtime__changed, vscan_svc_node_t *,
node);
(void) vscan_svc_setattr(idx, XAT_AV_SCANSTAMP);
break;
}
node->vsn_modified = 0;
(void) vscan_svc_setattr(idx,
XAT_AV_SCANSTAMP | XAT_AV_MODIFIED);
break;
case VS_STATUS_NO_SCAN:
if (node->vsn_quarantined)
node->vsn_access = VS_ACCESS_DENY;
else
node->vsn_access = VS_ACCESS_ALLOW;
break;
case VS_STATUS_ERROR:
case VS_STATUS_UNDEFINED:
default:
if ((node->vsn_quarantined) ||
(node->vsn_modified) ||
(node->vsn_scanstamp[0] == '\0'))
node->vsn_access = VS_ACCESS_DENY;
else
node->vsn_access = VS_ACCESS_ALLOW;
break;
}
DTRACE_PROBE4(vscan__result,
int, idx, int, node->vsn_req->vsr_seqnum,
int, node->vsn_result, int, node->vsn_access);
}
/*
* vscan_svc_getattr
*
* Get the vscan related system attributes, AT_SIZE & AT_MTIME.
*/
static int
vscan_svc_getattr(int idx)
{
xvattr_t xvattr;
xoptattr_t *xoap = NULL;
vnode_t *vp;
vscan_svc_node_t *node;
ASSERT(MUTEX_HELD(&vscan_svc_mutex));
node = &vscan_svc_nodes[idx];
if ((vp = node->vsn_req->vsr_vp) == NULL)
return (-1);
/* get the attributes */
xva_init(&xvattr); /* sets AT_XVATTR */
xvattr.xva_vattr.va_mask |= AT_SIZE;
xvattr.xva_vattr.va_mask |= AT_MTIME;
XVA_SET_REQ(&xvattr, XAT_AV_MODIFIED);
XVA_SET_REQ(&xvattr, XAT_AV_QUARANTINED);
XVA_SET_REQ(&xvattr, XAT_AV_SCANSTAMP);
if (VOP_GETATTR(vp, (vattr_t *)&xvattr, 0, kcred, NULL) != 0)
return (-1);
if ((xoap = xva_getxoptattr(&xvattr)) == NULL) {
cmn_err(CE_NOTE, "Virus scan request failed; "
"file system does not support virus scanning");
return (-1);
}
node->vsn_size = xvattr.xva_vattr.va_size;
node->vsn_mtime.tv_sec = xvattr.xva_vattr.va_mtime.tv_sec;
node->vsn_mtime.tv_nsec = xvattr.xva_vattr.va_mtime.tv_nsec;
if (XVA_ISSET_RTN(&xvattr, XAT_AV_MODIFIED) == 0)
return (-1);
node->vsn_modified = xoap->xoa_av_modified;
if (XVA_ISSET_RTN(&xvattr, XAT_AV_QUARANTINED) == 0)
return (-1);
node->vsn_quarantined = xoap->xoa_av_quarantined;
if (XVA_ISSET_RTN(&xvattr, XAT_AV_SCANSTAMP) != 0) {
(void) memcpy(node->vsn_scanstamp,
xoap->xoa_av_scanstamp, AV_SCANSTAMP_SZ);
}
DTRACE_PROBE1(vscan__getattr, vscan_svc_node_t *, node);
return (0);
}
/*
* vscan_svc_setattr
*
* Set the vscan related system attributes.
*/
static int
vscan_svc_setattr(int idx, int which)
{
xvattr_t xvattr;
xoptattr_t *xoap = NULL;
vnode_t *vp;
int len;
vscan_svc_node_t *node;
ASSERT(MUTEX_HELD(&vscan_svc_mutex));
node = &vscan_svc_nodes[idx];
if ((vp = node->vsn_req->vsr_vp) == NULL)
return (-1);
/* update the attributes */
xva_init(&xvattr); /* sets AT_XVATTR */
if ((xoap = xva_getxoptattr(&xvattr)) == NULL)
return (-1);
if (which & XAT_AV_MODIFIED) {
XVA_SET_REQ(&xvattr, XAT_AV_MODIFIED);
xoap->xoa_av_modified = node->vsn_modified;
}
if (which & XAT_AV_QUARANTINED) {
XVA_SET_REQ(&xvattr, XAT_AV_QUARANTINED);
xoap->xoa_av_quarantined = node->vsn_quarantined;
}
if (which & XAT_AV_SCANSTAMP) {
XVA_SET_REQ(&xvattr, XAT_AV_SCANSTAMP);
len = strlen(node->vsn_scanstamp);
(void) memcpy(xoap->xoa_av_scanstamp,
node->vsn_scanstamp, len);
}
/* if access is denied, set mtime to invalidate client cache */
if (node->vsn_access != VS_ACCESS_ALLOW) {
xvattr.xva_vattr.va_mask |= AT_MTIME;
gethrestime(&xvattr.xva_vattr.va_mtime);
}
if (VOP_SETATTR(vp, (vattr_t *)&xvattr, 0, kcred, NULL) != 0)
return (-1);
DTRACE_PROBE2(vscan__setattr,
vscan_svc_node_t *, node, int, which);
return (0);
}
/*
* vscan_svc_configure
*
* store configuration in vscan_svc_config
* set up vscan_svc_types array of pointers into
* vscan_svc_config.vsc_types for efficient searching
*/
int
vscan_svc_configure(vs_config_t *conf)
{
int count = 0;
char *p, *beg, *end;
mutex_enter(&vscan_svc_cfg_mutex);
vscan_svc_config = *conf;
(void) memset(vscan_svc_types, 0, sizeof (vscan_svc_types));
beg = vscan_svc_config.vsc_types;
end = beg + vscan_svc_config.vsc_types_len;
for (p = beg; p < end; p += strlen(p) + 1) {
if (count >= VS_TYPES_MAX) {
mutex_exit(&vscan_svc_mutex);
return (-1);
}
vscan_svc_types[count] = p;
++count;
}
mutex_exit(&vscan_svc_cfg_mutex);
return (0);
}
/*
* vscan_svc_exempt_file
*
* check if a file's size or type exempts it from virus scanning
*
* If the file is exempt from virus scanning, allow will be set
* to define whether files access should be allowed (B_TRUE) or
* denied (B_FALSE)
*
* Returns: 1 exempt
* 0 scan required
*/
static int
vscan_svc_exempt_file(vnode_t *vp, boolean_t *allow)
{
struct vattr attr;
ASSERT(vp != NULL);
ASSERT(vp->v_path != NULL);
attr.va_mask = AT_SIZE;
if (VOP_GETATTR(vp, &attr, 0, kcred, NULL) != 0) {
*allow = B_FALSE;
return (0);
}
mutex_enter(&vscan_svc_cfg_mutex);
if (attr.va_size > vscan_svc_config.vsc_max_size) {
DTRACE_PROBE2(vscan__exempt__filesize, char *,
vp->v_path, int, *allow);
*allow = (vscan_svc_config.vsc_allow) ? B_TRUE : B_FALSE;
mutex_exit(&vscan_svc_cfg_mutex);
return (1);
}
if (vscan_svc_exempt_filetype(vp->v_path)) {
DTRACE_PROBE1(vscan__exempt__filetype, char *, vp->v_path);
*allow = B_TRUE;
mutex_exit(&vscan_svc_cfg_mutex);
return (1);
}
mutex_exit(&vscan_svc_cfg_mutex);
return (0);
}
/*
* vscan_svc_exempt_filetype
*
* Each entry in vscan_svc_types includes a rule indicator (+,-)
* followed by the match string for file types to which the rule
* applies. Look for first match of file type in vscan_svc_types
* and return 1 (exempt) if the indicator is '-', and 0 (not exempt)
* if the indicator is '+'.
* If vscan_svc_match_ext fails, or no match is found, return 0
* (not exempt)
*
* Returns 1: exempt, 0: not exempt
*/
static int
vscan_svc_exempt_filetype(char *filepath)
{
int i, rc, exempt = 0;
char *filename, *ext;
ASSERT(MUTEX_HELD(&vscan_svc_cfg_mutex));
if ((filename = strrchr(filepath, '/')) == 0)
filename = filepath;
else
filename++;
if ((ext = strrchr(filename, '.')) == NULL)
ext = "";
else
ext++;
for (i = 0; i < VS_TYPES_MAX; i ++) {
if (vscan_svc_types[i] == 0)
break;
rc = vscan_svc_match_ext(vscan_svc_types[i] + 1, ext, 1);
if (rc == -1)
break;
if (rc > 0) {
DTRACE_PROBE2(vscan__type__match, char *, ext,
char *, vscan_svc_types[i]);
exempt = (vscan_svc_types[i][0] == '-');
break;
}
}
return (exempt);
}
/*
* vscan_svc_match_ext
*
* Performs a case-insensitive match for two strings. The first string
* argument can contain the wildcard characters '?' and '*'
*
* Returns: 0 no match
* 1 match
* -1 recursion error
*/
static int
vscan_svc_match_ext(char *patn, char *str, int depth)
{
int c1, c2;
if (depth > VS_EXT_RECURSE_DEPTH)
return (-1);
for (;;) {
switch (*patn) {
case 0:
return (*str == 0);
case '?':
if (*str != 0) {
str++;
patn++;
continue;
}
return (0);
case '*':
patn++;
if (*patn == 0)
return (1);
while (*str) {
if (vscan_svc_match_ext(patn, str, depth + 1))
return (1);
str++;
}
return (0);
default:
if (*str != *patn) {
c1 = *str;
c2 = *patn;
c1 = tolower(c1);
c2 = tolower(c2);
if (c1 != c2)
return (0);
}
str++;
patn++;
continue;
}
}
/* NOT REACHED */
}
/*
* vscan_svc_insert_req
*
* Insert request in next available available slot in vscan_svc_nodes
*
* Returns: idx of slot, or -1 if no slot available
*/
static int
vscan_svc_insert_req(vscan_req_t *req)
{
int idx;
vscan_svc_node_t *node;
ASSERT(MUTEX_HELD(&vscan_svc_mutex));
if (vscan_svc_counts.vsc_node == vs_nodes_max)
return (-1);
for (idx = 1; idx <= vs_nodes_max; idx++) {
if (vscan_svc_nodes[idx].vsn_req == NULL) {
req->vsr_idx = idx;
node = &vscan_svc_nodes[idx];
(void) memset(node, 0, sizeof (vscan_svc_node_t));
node->vsn_req = req;
node->vsn_modified = 1;
node->vsn_result = VS_STATUS_UNDEFINED;
node->vsn_access = VS_ACCESS_UNDEFINED;
++(vscan_svc_counts.vsc_node);
return (idx);
}
}
return (-1);
}
/*
* vscan_svc_remove_req
*/
static void
vscan_svc_remove_req(int idx)
{
ASSERT(MUTEX_HELD(&vscan_svc_mutex));
if (idx != 0) {
(void) memset(&vscan_svc_nodes[idx], 0,
sizeof (vscan_svc_node_t));
--(vscan_svc_counts.vsc_node);
}
}
/*
* vscan_svc_reql_find
*/
static vscan_req_t *
vscan_svc_reql_find(vnode_t *vp)
{
vscan_req_t *req;
ASSERT(MUTEX_HELD(&vscan_svc_mutex));
req = list_head(&vscan_svc_reql);
while (req != NULL) {
ASSERT(req->vsr_magic == VS_REQ_MAGIC);
if ((req->vsr_vp == vp) &&
(req->vsr_state != VS_SVC_REQ_COMPLETE))
break;
req = list_next(&vscan_svc_reql, req);
}
return (req);
}
/*
* vscan_svc_reql_insert
*/
static vscan_req_t *
vscan_svc_reql_insert(vnode_t *vp)
{
vscan_req_t *req;
ASSERT(MUTEX_HELD(&vscan_svc_mutex));
/* if request already in list then return it */
if ((req = vscan_svc_reql_find(vp)) != NULL)
return (req);
/* if list is full return NULL */
if (vscan_svc_counts.vsc_reql == vs_reqs_max)
return (NULL);
/* create a new request and insert into list */
VN_HOLD(vp);
req = kmem_zalloc(sizeof (vscan_req_t), KM_SLEEP);
req->vsr_magic = VS_REQ_MAGIC;
if (vscan_svc_seqnum == UINT32_MAX)
vscan_svc_seqnum = 0;
req->vsr_seqnum = ++vscan_svc_seqnum;
req->vsr_vp = vp;
req->vsr_refcnt = 1; /* decremented in vscan_svc_scan_complete */
req->vsr_state = VS_SVC_REQ_INIT;
cv_init(&(req->vsr_cv), NULL, CV_DEFAULT, NULL);
list_insert_tail(&vscan_svc_reql, req);
if (vscan_svc_reql_next == NULL)
vscan_svc_reql_next = req;
++(vscan_svc_counts.vsc_reql);
/* wake reql handler thread */
cv_signal(&vscan_svc_reql_cv);
return (req);
}
/*
* vscan_svc_reql_remove
*/
static void
vscan_svc_reql_remove(vscan_req_t *req)
{
ASSERT(MUTEX_HELD(&vscan_svc_mutex));
ASSERT(req->vsr_magic == VS_REQ_MAGIC);
if (vscan_svc_reql_next == req)
vscan_svc_reql_next = list_next(&vscan_svc_reql, req);
list_remove(&vscan_svc_reql, req);
cv_destroy(&(req->vsr_cv));
VN_RELE(req->vsr_vp);
kmem_free(req, sizeof (vscan_req_t));
--(vscan_svc_counts.vsc_reql);
}