NetBSD/sys/dist/pf/net/pf_ruleset.c

421 lines
11 KiB
C

/* $NetBSD: pf_ruleset.c,v 1.2 2008/06/18 09:06:27 yamt Exp $ */
/* $OpenBSD: pf_ruleset.c,v 1.1 2006/10/27 13:56:51 mcbride Exp $ */
/*
* Copyright (c) 2001 Daniel Hartmeier
* Copyright (c) 2002,2003 Henning Brauer
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - 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 THE COPYRIGHT HOLDERS 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
* COPYRIGHT HOLDERS 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.
*
* Effort sponsored in part by the Defense Advanced Research Projects
* Agency (DARPA) and Air Force Research Laboratory, Air Force
* Materiel Command, USAF, under agreement number F30602-01-2-0537.
*
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: pf_ruleset.c,v 1.2 2008/06/18 09:06:27 yamt Exp $");
#include <sys/param.h>
#include <sys/socket.h>
#ifdef _KERNEL
# include <sys/systm.h>
#endif /* _KERNEL */
#include <sys/mbuf.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/tcp.h>
#include <net/if.h>
#include <net/pfvar.h>
#ifdef INET6
#include <netinet/ip6.h>
#endif /* INET6 */
#ifdef _KERNEL
# define DPFPRINTF(format, x...) \
if (pf_status.debug >= PF_DEBUG_NOISY) \
printf(format , ##x)
#define rs_malloc(x) malloc(x, M_TEMP, M_WAITOK)
#define rs_free(x) free(x, M_TEMP)
#else
/* Userland equivalents so we can lend code to pfctl et al. */
# include <arpa/inet.h>
# include <errno.h>
# include <stdio.h>
# include <stdlib.h>
# include <string.h>
# define rs_malloc(x) malloc(x)
# define rs_free(x) free(x)
# ifdef PFDEBUG
# include <sys/stdarg.h>
# define DPFPRINTF(format, x...) fprintf(stderr, format , ##x)
# else
# define DPFPRINTF(format, x...) ((void)0)
# endif /* PFDEBUG */
#endif /* _KERNEL */
struct pf_anchor_global pf_anchors;
struct pf_anchor pf_main_anchor;
int pf_get_ruleset_number(u_int8_t);
void pf_init_ruleset(struct pf_ruleset *);
int pf_anchor_setup(struct pf_rule *,
const struct pf_ruleset *, const char *);
int pf_anchor_copyout(const struct pf_ruleset *,
const struct pf_rule *, struct pfioc_rule *);
void pf_anchor_remove(struct pf_rule *);
static __inline int pf_anchor_compare(struct pf_anchor *, struct pf_anchor *);
RB_GENERATE(pf_anchor_global, pf_anchor, entry_global, pf_anchor_compare);
RB_GENERATE(pf_anchor_node, pf_anchor, entry_node, pf_anchor_compare);
static __inline int
pf_anchor_compare(struct pf_anchor *a, struct pf_anchor *b)
{
int c = strcmp(a->path, b->path);
return (c ? (c < 0 ? -1 : 1) : 0);
}
int
pf_get_ruleset_number(u_int8_t action)
{
switch (action) {
case PF_SCRUB:
case PF_NOSCRUB:
return (PF_RULESET_SCRUB);
break;
case PF_PASS:
case PF_DROP:
return (PF_RULESET_FILTER);
break;
case PF_NAT:
case PF_NONAT:
return (PF_RULESET_NAT);
break;
case PF_BINAT:
case PF_NOBINAT:
return (PF_RULESET_BINAT);
break;
case PF_RDR:
case PF_NORDR:
return (PF_RULESET_RDR);
break;
default:
return (PF_RULESET_MAX);
break;
}
}
void
pf_init_ruleset(struct pf_ruleset *ruleset)
{
int i;
memset(ruleset, 0, sizeof(struct pf_ruleset));
for (i = 0; i < PF_RULESET_MAX; i++) {
TAILQ_INIT(&ruleset->rules[i].queues[0]);
TAILQ_INIT(&ruleset->rules[i].queues[1]);
ruleset->rules[i].active.ptr = &ruleset->rules[i].queues[0];
ruleset->rules[i].inactive.ptr = &ruleset->rules[i].queues[1];
}
}
struct pf_anchor *
pf_find_anchor(const char *path)
{
struct pf_anchor *key, *found;
key = (struct pf_anchor *)rs_malloc(sizeof(*key));
memset(key, 0, sizeof(*key));
strlcpy(key->path, path, sizeof(key->path));
found = RB_FIND(pf_anchor_global, &pf_anchors, key);
rs_free(key);
return (found);
}
struct pf_ruleset *
pf_find_ruleset(const char *path)
{
struct pf_anchor *anchor;
while (*path == '/')
path++;
if (!*path)
return (&pf_main_ruleset);
anchor = pf_find_anchor(path);
if (anchor == NULL)
return (NULL);
else
return (&anchor->ruleset);
}
struct pf_ruleset *
pf_find_or_create_ruleset(const char *path)
{
char *p, *q, *r;
struct pf_ruleset *ruleset;
struct pf_anchor *anchor = NULL /* XXX gcc */;
struct pf_anchor *dup, *parent = NULL;
if (path[0] == 0)
return (&pf_main_ruleset);
while (*path == '/')
path++;
ruleset = pf_find_ruleset(path);
if (ruleset != NULL)
return (ruleset);
p = (char *)rs_malloc(MAXPATHLEN);
bzero(p, MAXPATHLEN);
strlcpy(p, path, MAXPATHLEN);
while (parent == NULL && (q = strrchr(p, '/')) != NULL) {
*q = 0;
if ((ruleset = pf_find_ruleset(p)) != NULL) {
parent = ruleset->anchor;
break;
}
}
if (q == NULL)
q = p;
else
q++;
strlcpy(p, path, MAXPATHLEN);
if (!*q) {
rs_free(p);
return (NULL);
}
while ((r = strchr(q, '/')) != NULL || *q) {
if (r != NULL)
*r = 0;
if (!*q || strlen(q) >= PF_ANCHOR_NAME_SIZE ||
(parent != NULL && strlen(parent->path) >=
MAXPATHLEN - PF_ANCHOR_NAME_SIZE - 1)) {
rs_free(p);
return (NULL);
}
anchor = (struct pf_anchor *)rs_malloc(sizeof(*anchor));
if (anchor == NULL) {
rs_free(p);
return (NULL);
}
memset(anchor, 0, sizeof(*anchor));
RB_INIT(&anchor->children);
strlcpy(anchor->name, q, sizeof(anchor->name));
if (parent != NULL) {
strlcpy(anchor->path, parent->path,
sizeof(anchor->path));
strlcat(anchor->path, "/", sizeof(anchor->path));
}
strlcat(anchor->path, anchor->name, sizeof(anchor->path));
if ((dup = RB_INSERT(pf_anchor_global, &pf_anchors, anchor)) !=
NULL) {
printf("pf_find_or_create_ruleset: RB_INSERT1 "
"'%s' '%s' collides with '%s' '%s'\n",
anchor->path, anchor->name, dup->path, dup->name);
rs_free(anchor);
rs_free(p);
return (NULL);
}
if (parent != NULL) {
anchor->parent = parent;
if ((dup = RB_INSERT(pf_anchor_node, &parent->children,
anchor)) != NULL) {
printf("pf_find_or_create_ruleset: "
"RB_INSERT2 '%s' '%s' collides with "
"'%s' '%s'\n", anchor->path, anchor->name,
dup->path, dup->name);
RB_REMOVE(pf_anchor_global, &pf_anchors,
anchor);
rs_free(anchor);
rs_free(p);
return (NULL);
}
}
pf_init_ruleset(&anchor->ruleset);
anchor->ruleset.anchor = anchor;
parent = anchor;
if (r != NULL)
q = r + 1;
else
*q = 0;
}
rs_free(p);
return (&anchor->ruleset);
}
void
pf_remove_if_empty_ruleset(struct pf_ruleset *ruleset)
{
struct pf_anchor *parent;
int i;
while (ruleset != NULL) {
if (ruleset == &pf_main_ruleset || ruleset->anchor == NULL ||
!RB_EMPTY(&ruleset->anchor->children) ||
ruleset->anchor->refcnt > 0 || ruleset->tables > 0 ||
ruleset->topen)
return;
for (i = 0; i < PF_RULESET_MAX; ++i)
if (!TAILQ_EMPTY(ruleset->rules[i].active.ptr) ||
!TAILQ_EMPTY(ruleset->rules[i].inactive.ptr) ||
ruleset->rules[i].inactive.open)
return;
RB_REMOVE(pf_anchor_global, &pf_anchors, ruleset->anchor);
if ((parent = ruleset->anchor->parent) != NULL)
RB_REMOVE(pf_anchor_node, &parent->children,
ruleset->anchor);
rs_free(ruleset->anchor);
if (parent == NULL)
return;
ruleset = &parent->ruleset;
}
}
int
pf_anchor_setup(struct pf_rule *r, const struct pf_ruleset *s,
const char *name)
{
char *p, *path;
struct pf_ruleset *ruleset;
r->anchor = NULL;
r->anchor_relative = 0;
r->anchor_wildcard = 0;
if (!name[0])
return (0);
path = (char *)rs_malloc(MAXPATHLEN);
bzero(path, MAXPATHLEN);
if (name[0] == '/')
strlcpy(path, name + 1, MAXPATHLEN);
else {
/* relative path */
r->anchor_relative = 1;
if (s->anchor == NULL || !s->anchor->path[0])
path[0] = 0;
else
strlcpy(path, s->anchor->path, MAXPATHLEN);
while (name[0] == '.' && name[1] == '.' && name[2] == '/') {
if (!path[0]) {
printf("pf_anchor_setup: .. beyond root\n");
rs_free(path);
return (1);
}
if ((p = strrchr(path, '/')) != NULL)
*p = 0;
else
path[0] = 0;
r->anchor_relative++;
name += 3;
}
if (path[0])
strlcat(path, "/", MAXPATHLEN);
strlcat(path, name, MAXPATHLEN);
}
if ((p = strrchr(path, '/')) != NULL && !strcmp(p, "/*")) {
r->anchor_wildcard = 1;
*p = 0;
}
ruleset = pf_find_or_create_ruleset(path);
rs_free(path);
if (ruleset == NULL || ruleset->anchor == NULL) {
printf("pf_anchor_setup: ruleset\n");
return (1);
}
r->anchor = ruleset->anchor;
r->anchor->refcnt++;
return (0);
}
int
pf_anchor_copyout(const struct pf_ruleset *rs, const struct pf_rule *r,
struct pfioc_rule *pr)
{
pr->anchor_call[0] = 0;
if (r->anchor == NULL)
return (0);
if (!r->anchor_relative) {
strlcpy(pr->anchor_call, "/", sizeof(pr->anchor_call));
strlcat(pr->anchor_call, r->anchor->path,
sizeof(pr->anchor_call));
} else {
char *a, *p;
int i;
a = (char *)rs_malloc(MAXPATHLEN);
bzero(a, MAXPATHLEN);
if (rs->anchor == NULL)
a[0] = 0;
else
strlcpy(a, rs->anchor->path, MAXPATHLEN);
for (i = 1; i < r->anchor_relative; ++i) {
if ((p = strrchr(a, '/')) == NULL)
p = a;
*p = 0;
strlcat(pr->anchor_call, "../",
sizeof(pr->anchor_call));
}
if (strncmp(a, r->anchor->path, strlen(a))) {
printf("pf_anchor_copyout: '%s' '%s'\n", a,
r->anchor->path);
rs_free(a);
return (1);
}
if (strlen(r->anchor->path) > strlen(a))
strlcat(pr->anchor_call, r->anchor->path + (a[0] ?
strlen(a) + 1 : 0), sizeof(pr->anchor_call));
rs_free(a);
}
if (r->anchor_wildcard)
strlcat(pr->anchor_call, pr->anchor_call[0] ? "/*" : "*",
sizeof(pr->anchor_call));
return (0);
}
void
pf_anchor_remove(struct pf_rule *r)
{
if (r->anchor == NULL)
return;
if (r->anchor->refcnt <= 0) {
printf("pf_anchor_remove: broken refcount\n");
r->anchor = NULL;
return;
}
if (!--r->anchor->refcnt)
pf_remove_if_empty_ruleset(&r->anchor->ruleset);
r->anchor = NULL;
}