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Save 'ipfw forward' information in mtag, use m_pkthdr.fw_flags to indicate
[dragonfly/netmp.git] / sys / net / ipfw / ip_fw2.c
bloba58de15995a310244931dd39501f3478b5d78fa8
1 /*
2 * Copyright (c) 2002 Luigi Rizzo, Universita` di Pisa
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23 * SUCH DAMAGE.
24 *
25 * $FreeBSD: src/sys/netinet/ip_fw2.c,v 1.6.2.12 2003/04/08 10:42:32 maxim Exp $
26 * $DragonFly: src/sys/net/ipfw/ip_fw2.c,v 1.75 2008/08/22 09:14:16 sephe Exp $
27 */
28
29 #define DEB(x)
30 #define DDB(x) x
31
32 /*
33 * Implement IP packet firewall (new version)
34 */
35
36 #ifndef KLD_MODULE
37 #include "opt_ipfw.h"
38 #include "opt_ipdn.h"
39 #include "opt_ipdivert.h"
40 #include "opt_inet.h"
41 #ifndef INET
42 #error IPFIREWALL requires INET.
43 #endif /* INET */
44 #endif
45
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/malloc.h>
49 #include <sys/mbuf.h>
50 #include <sys/kernel.h>
51 #include <sys/proc.h>
52 #include <sys/socket.h>
53 #include <sys/socketvar.h>
54 #include <sys/sysctl.h>
55 #include <sys/syslog.h>
56 #include <sys/thread2.h>
57 #include <sys/ucred.h>
58 #include <sys/in_cksum.h>
59 #include <sys/lock.h>
60
61 #include <net/if.h>
62 #include <net/route.h>
63 #include <net/netmsg2.h>
64
65 #include <netinet/in.h>
66 #include <netinet/in_systm.h>
67 #include <netinet/in_var.h>
68 #include <netinet/in_pcb.h>
69 #include <netinet/ip.h>
70 #include <netinet/ip_var.h>
71 #include <netinet/ip_icmp.h>
72 #include "ip_fw.h"
73 #include <net/dummynet/ip_dummynet.h>
74 #include <netinet/tcp.h>
75 #include <netinet/tcp_timer.h>
76 #include <netinet/tcp_var.h>
77 #include <netinet/tcpip.h>
78 #include <netinet/udp.h>
79 #include <netinet/udp_var.h>
80
81 #include <netinet/if_ether.h> /* XXX for ETHERTYPE_IP */
82
83 /*
84 * Description about per-CPU rule duplication:
85 *
86 * Module loading/unloading and all ioctl operations are serialized
87 * by netisr0, so we don't have any ordering or locking problems.
88 *
89 * Following graph shows how operation on per-CPU rule list is
90 * performed [2 CPU case]:
91 *
92 * CPU0 CPU1
93 *
94 * netisr0 <------------------------------------+
95 * domsg |
96 * | |
97 * | netmsg |
98 * | |
99 * V |
100 * ifnet0 |
101 * : | netmsg
102 * :(delete/add...) |
103 * : |
104 * : netmsg |
105 * forwardmsg---------->ifnet1 |
106 * : |
107 * :(delete/add...) |
108 * : |
109 * : |
110 * replymsg--------------+
111 *
112 *
113 *
114 *
115 * Rules which will not create states (dyn rules) [2 CPU case]
116 *
117 * CPU0 CPU1
118 * layer3_chain layer3_chain
119 * | |
120 * V V
121 * +-------+ sibling +-------+ sibling
122 * | rule1 |--------->| rule1 |--------->NULL
123 * +-------+ +-------+
124 * | |
125 * |next |next
126 * V V
127 * +-------+ sibling +-------+ sibling
128 * | rule2 |--------->| rule2 |--------->NULL
129 * +-------+ +-------+
130 *
131 * ip_fw.sibling:
132 * 1) Ease statistics calculation during IP_FW_GET. We only need to
133 * iterate layer3_chain on CPU0; the current rule's duplication on
134 * the other CPUs could safely be read-only accessed by using
135 * ip_fw.sibling
136 * 2) Accelerate rule insertion and deletion, e.g. rule insertion:
137 * a) In netisr0 (on CPU0) rule3 is determined to be inserted between
138 * rule1 and rule2. To make this decision we need to iterate the
139 * layer3_chain on CPU0. The netmsg, which is used to insert the
140 * rule, will contain rule1 on CPU0 as prev_rule and rule2 on CPU0
141 * as next_rule
142 * b) After the insertion on CPU0 is done, we will move on to CPU1.
143 * But instead of relocating the rule3's position on CPU1 by
144 * iterating the layer3_chain on CPU1, we set the netmsg's prev_rule
145 * to rule1->sibling and next_rule to rule2->sibling before the
146 * netmsg is forwarded to CPU1 from CPU0
147 *
148 *
149 *
150 * Rules which will create states (dyn rules) [2 CPU case]
151 * (unnecessary parts are omitted; they are same as in the previous figure)
152 *
153 * CPU0 CPU1
154 *
155 * +-------+ +-------+
156 * | rule1 | | rule1 |
157 * +-------+ +-------+
158 * ^ | | ^
159 * | |stub stub| |
160 * | | | |
161 * | +----+ +----+ |
162 * | | | |
163 * | V V |
164 * | +--------------------+ |
165 * | | rule_stub | |
166 * | | (read-only shared) | |
167 * | | | |
168 * | | back pointer array | |
169 * | | (indexed by cpuid) | |
170 * | | | |
171 * +----|---------[0] | |
172 * | [1]--------|----+
173 * | |
174 * +--------------------+
175 * ^ ^
176 * | |
177 * ........|............|............
178 * : | | :
179 * : |stub |stub :
180 * : | | :
181 * : +---------+ +---------+ :
182 * : | state1a | | state1b | .... :
183 * : +---------+ +---------+ :
184 * : :
185 * : states table :
186 * : (shared) :
187 * : (protected by dyn_lock) :
188 * ..................................
189 *
190 * [state1a and state1b are states created by rule1]
191 *
192 * ip_fw_stub:
193 * This structure is introduced so that shared (locked) state table could
194 * work with per-CPU (duplicated) static rules. It mainly bridges states
195 * and static rules and serves as static rule's place holder (a read-only
196 * shared part of duplicated rules) from states point of view.
197 *
198 * IPFW_RULE_F_STATE (only for rules which create states):
199 * o During rule installation, this flag is turned on after rule's
200 * duplications reach all CPUs, to avoid at least following race:
201 * 1) rule1 is duplicated on CPU0 and is not duplicated on CPU1 yet
202 * 2) rule1 creates state1
203 * 3) state1 is located on CPU1 by check-state
204 * But rule1 is not duplicated on CPU1 yet
205 * o During rule deletion, this flag is turned off before deleting states
206 * created by the rule and before deleting the rule itself, so no
207 * more states will be created by the to-be-deleted rule even when its
208 * duplication on certain CPUs are not eliminated yet.
209 */
210
211 #define IPFW_AUTOINC_STEP_MIN 1
212 #define IPFW_AUTOINC_STEP_MAX 1000
213 #define IPFW_AUTOINC_STEP_DEF 100
214
215 #define IPFW_DEFAULT_RULE 65535 /* rulenum for the default rule */
216 #define IPFW_DEFAULT_SET 31 /* set number for the default rule */
217
218 struct netmsg_ipfw {
219 struct netmsg nmsg;
220 const struct ipfw_ioc_rule *ioc_rule;
221 struct ip_fw *next_rule;
222 struct ip_fw *prev_rule;
223 struct ip_fw *sibling;
224 struct ip_fw_stub *stub;
225 };
226
227 struct netmsg_del {
228 struct netmsg nmsg;
229 struct ip_fw *start_rule;
230 struct ip_fw *prev_rule;
231 uint16_t rulenum;
232 uint8_t from_set;
233 uint8_t to_set;
234 };
235
236 struct netmsg_zent {
237 struct netmsg nmsg;
238 struct ip_fw *start_rule;
239 uint16_t rulenum;
240 uint16_t log_only;
241 };
242
243 struct ipfw_context {
244 struct ip_fw *ipfw_layer3_chain; /* list of rules for layer3 */
245 struct ip_fw *ipfw_default_rule; /* default rule */
246 uint64_t ipfw_norule_counter; /* counter for ipfw_log(NULL) */
247
248 /*
249 * ipfw_set_disable contains one bit per set value (0..31).
250 * If the bit is set, all rules with the corresponding set
251 * are disabled. Set IPDW_DEFAULT_SET is reserved for the
252 * default rule and CANNOT be disabled.
253 */
254 uint32_t ipfw_set_disable;
255 uint32_t ipfw_gen; /* generation of rule list */
256 };
257
258 static struct ipfw_context *ipfw_ctx[MAXCPU];
259
260 #ifdef KLD_MODULE
261 /*
262 * Module can not be unloaded, if there are references to
263 * certains rules of ipfw(4), e.g. dummynet(4)
264 */
265 static int ipfw_refcnt;
266 #endif
267
268 MALLOC_DEFINE(M_IPFW, "IpFw/IpAcct", "IpFw/IpAcct chain's");
269
270 /*
271 * Following two global variables are accessed and
272 * updated only on CPU0
273 */
274 static uint32_t static_count; /* # of static rules */
275 static uint32_t static_ioc_len; /* bytes of static rules */
276
277 /*
278 * If 1, then ipfw static rules are being flushed,
279 * ipfw_chk() will skip to the default rule.
280 */
281 static int ipfw_flushing;
282
283 static int fw_verbose;
284 static int verbose_limit;
285
286 static int fw_debug = 1;
287 static int autoinc_step = IPFW_AUTOINC_STEP_DEF;
288
289 static int ipfw_sysctl_autoinc_step(SYSCTL_HANDLER_ARGS);
290 static int ipfw_sysctl_dyn_buckets(SYSCTL_HANDLER_ARGS);
291 static int ipfw_sysctl_dyn_fin(SYSCTL_HANDLER_ARGS);
292 static int ipfw_sysctl_dyn_rst(SYSCTL_HANDLER_ARGS);
293
294 #ifdef SYSCTL_NODE
295 SYSCTL_NODE(_net_inet_ip, OID_AUTO, fw, CTLFLAG_RW, 0, "Firewall");
296 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, enable, CTLFLAG_RW,
297 &fw_enable, 0, "Enable ipfw");
298 SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, autoinc_step, CTLTYPE_INT | CTLFLAG_RW,
299 &autoinc_step, 0, ipfw_sysctl_autoinc_step, "I",
300 "Rule number autincrement step");
301 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO,one_pass,CTLFLAG_RW,
302 &fw_one_pass, 0,
303 "Only do a single pass through ipfw when using dummynet(4)");
304 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, debug, CTLFLAG_RW,
305 &fw_debug, 0, "Enable printing of debug ip_fw statements");
306 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, verbose, CTLFLAG_RW,
307 &fw_verbose, 0, "Log matches to ipfw rules");
308 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, verbose_limit, CTLFLAG_RW,
309 &verbose_limit, 0, "Set upper limit of matches of ipfw rules logged");
310
311 /*
312 * Description of dynamic rules.
313 *
314 * Dynamic rules are stored in lists accessed through a hash table
315 * (ipfw_dyn_v) whose size is curr_dyn_buckets. This value can
316 * be modified through the sysctl variable dyn_buckets which is
317 * updated when the table becomes empty.
318 *
319 * XXX currently there is only one list, ipfw_dyn.
320 *
321 * When a packet is received, its address fields are first masked
322 * with the mask defined for the rule, then hashed, then matched
323 * against the entries in the corresponding list.
324 * Dynamic rules can be used for different purposes:
325 * + stateful rules;
326 * + enforcing limits on the number of sessions;
327 * + in-kernel NAT (not implemented yet)
328 *
329 * The lifetime of dynamic rules is regulated by dyn_*_lifetime,
330 * measured in seconds and depending on the flags.
331 *
332 * The total number of dynamic rules is stored in dyn_count.
333 * The max number of dynamic rules is dyn_max. When we reach
334 * the maximum number of rules we do not create anymore. This is
335 * done to avoid consuming too much memory, but also too much
336 * time when searching on each packet (ideally, we should try instead
337 * to put a limit on the length of the list on each bucket...).
338 *
339 * Each dynamic rule holds a pointer to the parent ipfw rule so
340 * we know what action to perform. Dynamic rules are removed when
341 * the parent rule is deleted. XXX we should make them survive.
342 *
343 * There are some limitations with dynamic rules -- we do not
344 * obey the 'randomized match', and we do not do multiple
345 * passes through the firewall. XXX check the latter!!!
346 *
347 * NOTE about the SHARED LOCKMGR LOCK during dynamic rule looking up:
348 * Only TCP state transition will change dynamic rule's state and ack
349 * sequences, while all packets of one TCP connection only goes through
350 * one TCP thread, so it is safe to use shared lockmgr lock during dynamic
351 * rule looking up. The keep alive callout uses exclusive lockmgr lock
352 * when it tries to find suitable dynamic rules to send keep alive, so
353 * it will not see half updated state and ack sequences. Though the expire
354 * field updating looks racy for other protocols, the resolution (second)
355 * of expire field makes this kind of race harmless.
356 * XXX statistics' updating is _not_ MPsafe!!!
357 * XXX once UDP output path is fixed, we could use lockless dynamic rule
358 * hash table
359 */
360 static ipfw_dyn_rule **ipfw_dyn_v = NULL;
361 static uint32_t dyn_buckets = 256; /* must be power of 2 */
362 static uint32_t curr_dyn_buckets = 256; /* must be power of 2 */
363 static uint32_t dyn_buckets_gen; /* generation of dyn buckets array */
364 static struct lock dyn_lock; /* dynamic rules' hash table lock */
365 static struct callout ipfw_timeout_h;
366
367 /*
368 * Timeouts for various events in handing dynamic rules.
369 */
370 static uint32_t dyn_ack_lifetime = 300;
371 static uint32_t dyn_syn_lifetime = 20;
372 static uint32_t dyn_fin_lifetime = 1;
373 static uint32_t dyn_rst_lifetime = 1;
374 static uint32_t dyn_udp_lifetime = 10;
375 static uint32_t dyn_short_lifetime = 5;
376
377 /*
378 * Keepalives are sent if dyn_keepalive is set. They are sent every
379 * dyn_keepalive_period seconds, in the last dyn_keepalive_interval
380 * seconds of lifetime of a rule.
381 * dyn_rst_lifetime and dyn_fin_lifetime should be strictly lower
382 * than dyn_keepalive_period.
383 */
384
385 static uint32_t dyn_keepalive_interval = 20;
386 static uint32_t dyn_keepalive_period = 5;
387 static uint32_t dyn_keepalive = 1; /* do send keepalives */
388
389 static uint32_t dyn_count; /* # of dynamic rules */
390 static uint32_t dyn_max = 4096; /* max # of dynamic rules */
391
392 SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, dyn_buckets, CTLTYPE_INT | CTLFLAG_RW,
393 &dyn_buckets, 0, ipfw_sysctl_dyn_buckets, "I", "Number of dyn. buckets");
394 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, curr_dyn_buckets, CTLFLAG_RD,
395 &curr_dyn_buckets, 0, "Current Number of dyn. buckets");
396 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_count, CTLFLAG_RD,
397 &dyn_count, 0, "Number of dyn. rules");
398 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_max, CTLFLAG_RW,
399 &dyn_max, 0, "Max number of dyn. rules");
400 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, static_count, CTLFLAG_RD,
401 &static_count, 0, "Number of static rules");
402 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_ack_lifetime, CTLFLAG_RW,
403 &dyn_ack_lifetime, 0, "Lifetime of dyn. rules for acks");
404 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_syn_lifetime, CTLFLAG_RW,
405 &dyn_syn_lifetime, 0, "Lifetime of dyn. rules for syn");
406 SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, dyn_fin_lifetime,
407 CTLTYPE_INT | CTLFLAG_RW, &dyn_fin_lifetime, 0, ipfw_sysctl_dyn_fin, "I",
408 "Lifetime of dyn. rules for fin");
409 SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, dyn_rst_lifetime,
410 CTLTYPE_INT | CTLFLAG_RW, &dyn_rst_lifetime, 0, ipfw_sysctl_dyn_rst, "I",
411 "Lifetime of dyn. rules for rst");
412 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_udp_lifetime, CTLFLAG_RW,
413 &dyn_udp_lifetime, 0, "Lifetime of dyn. rules for UDP");
414 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_short_lifetime, CTLFLAG_RW,
415 &dyn_short_lifetime, 0, "Lifetime of dyn. rules for other situations");
416 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_keepalive, CTLFLAG_RW,
417 &dyn_keepalive, 0, "Enable keepalives for dyn. rules");
418
419 #endif /* SYSCTL_NODE */
420
421 static ip_fw_chk_t ipfw_chk;
422
423 static __inline int
424 ipfw_free_rule(struct ip_fw *rule)
425 {
426 KASSERT(rule->cpuid == mycpuid, ("rule freed on cpu%d\n", mycpuid));
427 KASSERT(rule->refcnt > 0, ("invalid refcnt %u\n", rule->refcnt));
428 rule->refcnt--;
429 if (rule->refcnt == 0) {
430 kfree(rule, M_IPFW);
431 return 1;
432 }
433 return 0;
434 }
435
436 static void
437 ipfw_unref_rule(void *priv)
438 {
439 ipfw_free_rule(priv);
440 #ifdef KLD_MODULE
441 atomic_subtract_int(&ipfw_refcnt, 1);
442 #endif
443 }
444
445 static __inline void
446 ipfw_ref_rule(struct ip_fw *rule)
447 {
448 KASSERT(rule->cpuid == mycpuid, ("rule used on cpu%d\n", mycpuid));
449 #ifdef KLD_MODULE
450 atomic_add_int(&ipfw_refcnt, 1);
451 #endif
452 rule->refcnt++;
453 }
454
455 /*
456 * This macro maps an ip pointer into a layer3 header pointer of type T
457 */
458 #define L3HDR(T, ip) ((T *)((uint32_t *)(ip) + (ip)->ip_hl))
459
460 static __inline int
461 icmptype_match(struct ip *ip, ipfw_insn_u32 *cmd)
462 {
463 int type = L3HDR(struct icmp,ip)->icmp_type;
464
465 return (type <= ICMP_MAXTYPE && (cmd->d[0] & (1 << type)));
466 }
467
468 #define TT ((1 << ICMP_ECHO) | \
469 (1 << ICMP_ROUTERSOLICIT) | \
470 (1 << ICMP_TSTAMP) | \
471 (1 << ICMP_IREQ) | \
472 (1 << ICMP_MASKREQ))
473
474 static int
475 is_icmp_query(struct ip *ip)
476 {
477 int type = L3HDR(struct icmp, ip)->icmp_type;
478
479 return (type <= ICMP_MAXTYPE && (TT & (1 << type)));
480 }
481
482 #undef TT
483
484 /*
485 * The following checks use two arrays of 8 or 16 bits to store the
486 * bits that we want set or clear, respectively. They are in the
487 * low and high half of cmd->arg1 or cmd->d[0].
488 *
489 * We scan options and store the bits we find set. We succeed if
490 *
491 * (want_set & ~bits) == 0 && (want_clear & ~bits) == want_clear
492 *
493 * The code is sometimes optimized not to store additional variables.
494 */
495
496 static int
497 flags_match(ipfw_insn *cmd, uint8_t bits)
498 {
499 u_char want_clear;
500 bits = ~bits;
501
502 if (((cmd->arg1 & 0xff) & bits) != 0)
503 return 0; /* some bits we want set were clear */
504
505 want_clear = (cmd->arg1 >> 8) & 0xff;
506 if ((want_clear & bits) != want_clear)
507 return 0; /* some bits we want clear were set */
508 return 1;
509 }
510
511 static int
512 ipopts_match(struct ip *ip, ipfw_insn *cmd)
513 {
514 int optlen, bits = 0;
515 u_char *cp = (u_char *)(ip + 1);
516 int x = (ip->ip_hl << 2) - sizeof(struct ip);
517
518 for (; x > 0; x -= optlen, cp += optlen) {
519 int opt = cp[IPOPT_OPTVAL];
520
521 if (opt == IPOPT_EOL)
522 break;
523
524 if (opt == IPOPT_NOP) {
525 optlen = 1;
526 } else {
527 optlen = cp[IPOPT_OLEN];
528 if (optlen <= 0 || optlen > x)
529 return 0; /* invalid or truncated */
530 }
531
532 switch (opt) {
533 case IPOPT_LSRR:
534 bits |= IP_FW_IPOPT_LSRR;
535 break;
536
537 case IPOPT_SSRR:
538 bits |= IP_FW_IPOPT_SSRR;
539 break;
540
541 case IPOPT_RR:
542 bits |= IP_FW_IPOPT_RR;
543 break;
544
545 case IPOPT_TS:
546 bits |= IP_FW_IPOPT_TS;
547 break;
548
549 default:
550 break;
551 }
552 }
553 return (flags_match(cmd, bits));
554 }
555
556 static int
557 tcpopts_match(struct ip *ip, ipfw_insn *cmd)
558 {
559 int optlen, bits = 0;
560 struct tcphdr *tcp = L3HDR(struct tcphdr,ip);
561 u_char *cp = (u_char *)(tcp + 1);
562 int x = (tcp->th_off << 2) - sizeof(struct tcphdr);
563
564 for (; x > 0; x -= optlen, cp += optlen) {
565 int opt = cp[0];
566
567 if (opt == TCPOPT_EOL)
568 break;
569
570 if (opt == TCPOPT_NOP) {
571 optlen = 1;
572 } else {
573 optlen = cp[1];
574 if (optlen <= 0)
575 break;
576 }
577
578 switch (opt) {
579 case TCPOPT_MAXSEG:
580 bits |= IP_FW_TCPOPT_MSS;
581 break;
582
583 case TCPOPT_WINDOW:
584 bits |= IP_FW_TCPOPT_WINDOW;
585 break;
586
587 case TCPOPT_SACK_PERMITTED:
588 case TCPOPT_SACK:
589 bits |= IP_FW_TCPOPT_SACK;
590 break;
591
592 case TCPOPT_TIMESTAMP:
593 bits |= IP_FW_TCPOPT_TS;
594 break;
595
596 case TCPOPT_CC:
597 case TCPOPT_CCNEW:
598 case TCPOPT_CCECHO:
599 bits |= IP_FW_TCPOPT_CC;
600 break;
601
602 default:
603 break;
604 }
605 }
606 return (flags_match(cmd, bits));
607 }
608
609 static int
610 iface_match(struct ifnet *ifp, ipfw_insn_if *cmd)
611 {
612 if (ifp == NULL) /* no iface with this packet, match fails */
613 return 0;
614
615 /* Check by name or by IP address */
616 if (cmd->name[0] != '\0') { /* match by name */
617 /* Check name */
618 if (cmd->p.glob) {
619 if (kfnmatch(cmd->name, ifp->if_xname, 0) == 0)
620 return(1);
621 } else {
622 if (strncmp(ifp->if_xname, cmd->name, IFNAMSIZ) == 0)
623 return(1);
624 }
625 } else {
626 struct ifaddr_container *ifac;
627
628 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
629 struct ifaddr *ia = ifac->ifa;
630
631 if (ia->ifa_addr == NULL)
632 continue;
633 if (ia->ifa_addr->sa_family != AF_INET)
634 continue;
635 if (cmd->p.ip.s_addr == ((struct sockaddr_in *)
636 (ia->ifa_addr))->sin_addr.s_addr)
637 return(1); /* match */
638 }
639 }
640 return(0); /* no match, fail ... */
641 }
642
643 #define SNPARGS(buf, len) buf + len, sizeof(buf) > len ? sizeof(buf) - len : 0
644
645 /*
646 * We enter here when we have a rule with O_LOG.
647 * XXX this function alone takes about 2Kbytes of code!
648 */
649 static void
650 ipfw_log(struct ip_fw *f, u_int hlen, struct ether_header *eh,
651 struct mbuf *m, struct ifnet *oif)
652 {
653 char *action;
654 int limit_reached = 0;
655 char action2[40], proto[48], fragment[28];
656
657 fragment[0] = '\0';
658 proto[0] = '\0';
659
660 if (f == NULL) { /* bogus pkt */
661 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
662
663 if (verbose_limit != 0 &&
664 ctx->ipfw_norule_counter >= verbose_limit)
665 return;
666 ctx->ipfw_norule_counter++;
667 if (ctx->ipfw_norule_counter == verbose_limit)
668 limit_reached = verbose_limit;
669 action = "Refuse";
670 } else { /* O_LOG is the first action, find the real one */
671 ipfw_insn *cmd = ACTION_PTR(f);
672 ipfw_insn_log *l = (ipfw_insn_log *)cmd;
673
674 if (l->max_log != 0 && l->log_left == 0)
675 return;
676 l->log_left--;
677 if (l->log_left == 0)
678 limit_reached = l->max_log;
679 cmd += F_LEN(cmd); /* point to first action */
680 if (cmd->opcode == O_PROB)
681 cmd += F_LEN(cmd);
682
683 action = action2;
684 switch (cmd->opcode) {
685 case O_DENY:
686 action = "Deny";
687 break;
688
689 case O_REJECT:
690 if (cmd->arg1==ICMP_REJECT_RST) {
691 action = "Reset";
692 } else if (cmd->arg1==ICMP_UNREACH_HOST) {
693 action = "Reject";
694 } else {
695 ksnprintf(SNPARGS(action2, 0), "Unreach %d",
696 cmd->arg1);
697 }
698 break;
699
700 case O_ACCEPT:
701 action = "Accept";
702 break;
703
704 case O_COUNT:
705 action = "Count";
706 break;
707
708 case O_DIVERT:
709 ksnprintf(SNPARGS(action2, 0), "Divert %d", cmd->arg1);
710 break;
711
712 case O_TEE:
713 ksnprintf(SNPARGS(action2, 0), "Tee %d", cmd->arg1);
714 break;
715
716 case O_SKIPTO:
717 ksnprintf(SNPARGS(action2, 0), "SkipTo %d", cmd->arg1);
718 break;
719
720 case O_PIPE:
721 ksnprintf(SNPARGS(action2, 0), "Pipe %d", cmd->arg1);
722 break;
723
724 case O_QUEUE:
725 ksnprintf(SNPARGS(action2, 0), "Queue %d", cmd->arg1);
726 break;
727
728 case O_FORWARD_IP:
729 {
730 ipfw_insn_sa *sa = (ipfw_insn_sa *)cmd;
731 int len;
732
733 len = ksnprintf(SNPARGS(action2, 0),
734 "Forward to %s",
735 inet_ntoa(sa->sa.sin_addr));
736 if (sa->sa.sin_port) {
737 ksnprintf(SNPARGS(action2, len), ":%d",
738 sa->sa.sin_port);
739 }
740 }
741 break;
742
743 default:
744 action = "UNKNOWN";
745 break;
746 }
747 }
748
749 if (hlen == 0) { /* non-ip */
750 ksnprintf(SNPARGS(proto, 0), "MAC");
751 } else {
752 struct ip *ip = mtod(m, struct ip *);
753 /* these three are all aliases to the same thing */
754 struct icmp *const icmp = L3HDR(struct icmp, ip);
755 struct tcphdr *const tcp = (struct tcphdr *)icmp;
756 struct udphdr *const udp = (struct udphdr *)icmp;
757
758 int ip_off, offset, ip_len;
759 int len;
760
761 if (eh != NULL) { /* layer 2 packets are as on the wire */
762 ip_off = ntohs(ip->ip_off);
763 ip_len = ntohs(ip->ip_len);
764 } else {
765 ip_off = ip->ip_off;
766 ip_len = ip->ip_len;
767 }
768 offset = ip_off & IP_OFFMASK;
769 switch (ip->ip_p) {
770 case IPPROTO_TCP:
771 len = ksnprintf(SNPARGS(proto, 0), "TCP %s",
772 inet_ntoa(ip->ip_src));
773 if (offset == 0) {
774 ksnprintf(SNPARGS(proto, len), ":%d %s:%d",
775 ntohs(tcp->th_sport),
776 inet_ntoa(ip->ip_dst),
777 ntohs(tcp->th_dport));
778 } else {
779 ksnprintf(SNPARGS(proto, len), " %s",
780 inet_ntoa(ip->ip_dst));
781 }
782 break;
783
784 case IPPROTO_UDP:
785 len = ksnprintf(SNPARGS(proto, 0), "UDP %s",
786 inet_ntoa(ip->ip_src));
787 if (offset == 0) {
788 ksnprintf(SNPARGS(proto, len), ":%d %s:%d",
789 ntohs(udp->uh_sport),
790 inet_ntoa(ip->ip_dst),
791 ntohs(udp->uh_dport));
792 } else {
793 ksnprintf(SNPARGS(proto, len), " %s",
794 inet_ntoa(ip->ip_dst));
795 }
796 break;
797
798 case IPPROTO_ICMP:
799 if (offset == 0) {
800 len = ksnprintf(SNPARGS(proto, 0),
801 "ICMP:%u.%u ",
802 icmp->icmp_type,
803 icmp->icmp_code);
804 } else {
805 len = ksnprintf(SNPARGS(proto, 0), "ICMP ");
806 }
807 len += ksnprintf(SNPARGS(proto, len), "%s",
808 inet_ntoa(ip->ip_src));
809 ksnprintf(SNPARGS(proto, len), " %s",
810 inet_ntoa(ip->ip_dst));
811 break;
812
813 default:
814 len = ksnprintf(SNPARGS(proto, 0), "P:%d %s", ip->ip_p,
815 inet_ntoa(ip->ip_src));
816 ksnprintf(SNPARGS(proto, len), " %s",
817 inet_ntoa(ip->ip_dst));
818 break;
819 }
820
821 if (ip_off & (IP_MF | IP_OFFMASK)) {
822 ksnprintf(SNPARGS(fragment, 0), " (frag %d:%d@%d%s)",
823 ntohs(ip->ip_id), ip_len - (ip->ip_hl << 2),
824 offset << 3, (ip_off & IP_MF) ? "+" : "");
825 }
826 }
827
828 if (oif || m->m_pkthdr.rcvif) {
829 log(LOG_SECURITY | LOG_INFO,
830 "ipfw: %d %s %s %s via %s%s\n",
831 f ? f->rulenum : -1,
832 action, proto, oif ? "out" : "in",
833 oif ? oif->if_xname : m->m_pkthdr.rcvif->if_xname,
834 fragment);
835 } else {
836 log(LOG_SECURITY | LOG_INFO,
837 "ipfw: %d %s %s [no if info]%s\n",
838 f ? f->rulenum : -1,
839 action, proto, fragment);
840 }
841
842 if (limit_reached) {
843 log(LOG_SECURITY | LOG_NOTICE,
844 "ipfw: limit %d reached on entry %d\n",
845 limit_reached, f ? f->rulenum : -1);
846 }
847 }
848
849 #undef SNPARGS
850
851 /*
852 * IMPORTANT: the hash function for dynamic rules must be commutative
853 * in source and destination (ip,port), because rules are bidirectional
854 * and we want to find both in the same bucket.
855 */
856 static __inline int
857 hash_packet(struct ipfw_flow_id *id)
858 {
859 uint32_t i;
860
861 i = (id->dst_ip) ^ (id->src_ip) ^ (id->dst_port) ^ (id->src_port);
862 i &= (curr_dyn_buckets - 1);
863 return i;
864 }
865
866 /**
867 * unlink a dynamic rule from a chain. prev is a pointer to
868 * the previous one, q is a pointer to the rule to delete,
869 * head is a pointer to the head of the queue.
870 * Modifies q and potentially also head.
871 */
872 #define UNLINK_DYN_RULE(prev, head, q) \
873 do { \
874 ipfw_dyn_rule *old_q = q; \
875 \
876 /* remove a refcount to the parent */ \
877 if (q->dyn_type == O_LIMIT) \
878 q->parent->count--; \
879 DEB(kprintf("-- unlink entry 0x%08x %d -> 0x%08x %d, %d left\n", \
880 (q->id.src_ip), (q->id.src_port), \
881 (q->id.dst_ip), (q->id.dst_port), dyn_count-1 ); ) \
882 if (prev != NULL) \
883 prev->next = q = q->next; \
884 else \
885 head = q = q->next; \
886 KASSERT(dyn_count > 0, ("invalid dyn count %u\n", dyn_count)); \
887 dyn_count--; \
888 kfree(old_q, M_IPFW); \
889 } while (0)
890
891 #define TIME_LEQ(a, b) ((int)((a) - (b)) <= 0)
892
893 /**
894 * Remove dynamic rules pointing to "rule", or all of them if rule == NULL.
895 *
896 * If keep_me == NULL, rules are deleted even if not expired,
897 * otherwise only expired rules are removed.
898 *
899 * The value of the second parameter is also used to point to identify
900 * a rule we absolutely do not want to remove (e.g. because we are
901 * holding a reference to it -- this is the case with O_LIMIT_PARENT
902 * rules). The pointer is only used for comparison, so any non-null
903 * value will do.
904 */
905 static void
906 remove_dyn_rule_locked(struct ip_fw *rule, ipfw_dyn_rule *keep_me)
907 {
908 static uint32_t last_remove = 0; /* XXX */
909
910 #define FORCE (keep_me == NULL)
911
912 ipfw_dyn_rule *prev, *q;
913 int i, pass = 0, max_pass = 0, unlinked = 0;
914
915 if (ipfw_dyn_v == NULL || dyn_count == 0)
916 return;
917 /* do not expire more than once per second, it is useless */
918 if (!FORCE && last_remove == time_second)
919 return;
920 last_remove = time_second;
921
922 /*
923 * because O_LIMIT refer to parent rules, during the first pass only
924 * remove child and mark any pending LIMIT_PARENT, and remove
925 * them in a second pass.
926 */
927 next_pass:
928 for (i = 0; i < curr_dyn_buckets; i++) {
929 for (prev = NULL, q = ipfw_dyn_v[i]; q;) {
930 /*
931 * Logic can become complex here, so we split tests.
932 */
933 if (q == keep_me)
934 goto next;
935 if (rule != NULL && rule->stub != q->stub)
936 goto next; /* not the one we are looking for */
937 if (q->dyn_type == O_LIMIT_PARENT) {
938 /*
939 * handle parent in the second pass,
940 * record we need one.
941 */
942 max_pass = 1;
943 if (pass == 0)
944 goto next;
945 if (FORCE && q->count != 0) {
946 /* XXX should not happen! */
947 kprintf("OUCH! cannot remove rule, "
948 "count %d\n", q->count);
949 }
950 } else {
951 if (!FORCE && !TIME_LEQ(q->expire, time_second))
952 goto next;
953 }
954 unlinked = 1;
955 UNLINK_DYN_RULE(prev, ipfw_dyn_v[i], q);
956 continue;
957 next:
958 prev = q;
959 q = q->next;
960 }
961 }
962 if (pass++ < max_pass)
963 goto next_pass;
964
965 if (unlinked)
966 ++dyn_buckets_gen;
967
968 #undef FORCE
969 }
970
971 /**
972 * lookup a dynamic rule.
973 */
974 static ipfw_dyn_rule *
975 lookup_dyn_rule(struct ipfw_flow_id *pkt, int *match_direction,
976 struct tcphdr *tcp)
977 {
978 /*
979 * stateful ipfw extensions.
980 * Lookup into dynamic session queue
981 */
982 #define MATCH_REVERSE 0
983 #define MATCH_FORWARD 1
984 #define MATCH_NONE 2
985 #define MATCH_UNKNOWN 3
986 int i, dir = MATCH_NONE;
987 ipfw_dyn_rule *prev, *q=NULL;
988
989 if (ipfw_dyn_v == NULL)
990 goto done; /* not found */
991
992 i = hash_packet(pkt);
993 for (prev = NULL, q = ipfw_dyn_v[i]; q != NULL;) {
994 if (q->dyn_type == O_LIMIT_PARENT)
995 goto next;
996
997 if (TIME_LEQ(q->expire, time_second)) {
998 /*
999 * Entry expired; skip.
1000 * Let ipfw_tick() take care of it
1001 */
1002 goto next;
1003 }
1004
1005 if (pkt->proto == q->id.proto) {
1006 if (pkt->src_ip == q->id.src_ip &&
1007 pkt->dst_ip == q->id.dst_ip &&
1008 pkt->src_port == q->id.src_port &&
1009 pkt->dst_port == q->id.dst_port) {
1010 dir = MATCH_FORWARD;
1011 break;
1012 }
1013 if (pkt->src_ip == q->id.dst_ip &&
1014 pkt->dst_ip == q->id.src_ip &&
1015 pkt->src_port == q->id.dst_port &&
1016 pkt->dst_port == q->id.src_port) {
1017 dir = MATCH_REVERSE;
1018 break;
1019 }
1020 }
1021 next:
1022 prev = q;
1023 q = q->next;
1024 }
1025 if (q == NULL)
1026 goto done; /* q = NULL, not found */
1027
1028 if (pkt->proto == IPPROTO_TCP) { /* update state according to flags */
1029 u_char flags = pkt->flags & (TH_FIN|TH_SYN|TH_RST);
1030
1031 #define BOTH_SYN (TH_SYN | (TH_SYN << 8))
1032 #define BOTH_FIN (TH_FIN | (TH_FIN << 8))
1033
1034 q->state |= (dir == MATCH_FORWARD ) ? flags : (flags << 8);
1035 switch (q->state) {
1036 case TH_SYN: /* opening */
1037 q->expire = time_second + dyn_syn_lifetime;
1038 break;
1039
1040 case BOTH_SYN: /* move to established */
1041 case BOTH_SYN | TH_FIN : /* one side tries to close */
1042 case BOTH_SYN | (TH_FIN << 8) :
1043 if (tcp) {
1044 uint32_t ack = ntohl(tcp->th_ack);
1045
1046 #define _SEQ_GE(a, b) ((int)(a) - (int)(b) >= 0)
1047
1048 if (dir == MATCH_FORWARD) {
1049 if (q->ack_fwd == 0 ||
1050 _SEQ_GE(ack, q->ack_fwd))
1051 q->ack_fwd = ack;
1052 else /* ignore out-of-sequence */
1053 break;
1054 } else {
1055 if (q->ack_rev == 0 ||
1056 _SEQ_GE(ack, q->ack_rev))
1057 q->ack_rev = ack;
1058 else /* ignore out-of-sequence */
1059 break;
1060 }
1061 #undef _SEQ_GE
1062 }
1063 q->expire = time_second + dyn_ack_lifetime;
1064 break;
1065
1066 case BOTH_SYN | BOTH_FIN: /* both sides closed */
1067 KKASSERT(dyn_fin_lifetime < dyn_keepalive_period);
1068 q->expire = time_second + dyn_fin_lifetime;
1069 break;
1070
1071 default:
1072 #if 0
1073 /*
1074 * reset or some invalid combination, but can also
1075 * occur if we use keep-state the wrong way.
1076 */
1077 if ((q->state & ((TH_RST << 8) | TH_RST)) == 0)
1078 kprintf("invalid state: 0x%x\n", q->state);
1079 #endif
1080 KKASSERT(dyn_rst_lifetime < dyn_keepalive_period);
1081 q->expire = time_second + dyn_rst_lifetime;
1082 break;
1083 }
1084 } else if (pkt->proto == IPPROTO_UDP) {
1085 q->expire = time_second + dyn_udp_lifetime;
1086 } else {
1087 /* other protocols */
1088 q->expire = time_second + dyn_short_lifetime;
1089 }
1090 done:
1091 if (match_direction)
1092 *match_direction = dir;
1093 return q;
1094 }
1095
1096 static struct ip_fw *
1097 lookup_rule(struct ipfw_flow_id *pkt, int *match_direction, struct tcphdr *tcp,
1098 uint16_t len, int *deny)
1099 {
1100 struct ip_fw *rule = NULL;
1101 ipfw_dyn_rule *q;
1102 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
1103 uint32_t gen;
1104
1105 *deny = 0;
1106 gen = ctx->ipfw_gen;
1107
1108 lockmgr(&dyn_lock, LK_SHARED);
1109
1110 if (ctx->ipfw_gen != gen) {
1111 /*
1112 * Static rules had been change when we were waiting
1113 * for the dynamic hash table lock; deny this packet,
1114 * since it is _not_ known whether it is safe to keep
1115 * iterating the static rules.
1116 */
1117 *deny = 1;
1118 goto back;
1119 }
1120
1121 q = lookup_dyn_rule(pkt, match_direction, tcp);
1122 if (q == NULL) {
1123 rule = NULL;
1124 } else {
1125 rule = q->stub->rule[mycpuid];
1126 KKASSERT(rule->stub == q->stub && rule->cpuid == mycpuid);
1127
1128 /* XXX */
1129 q->pcnt++;
1130 q->bcnt += len;
1131 }
1132 back:
1133 lockmgr(&dyn_lock, LK_RELEASE);
1134 return rule;
1135 }
1136
1137 static void
1138 realloc_dynamic_table(void)
1139 {
1140 ipfw_dyn_rule **old_dyn_v;
1141 uint32_t old_curr_dyn_buckets;
1142
1143 KASSERT(dyn_buckets <= 65536 && (dyn_buckets & (dyn_buckets - 1)) == 0,
1144 ("invalid dyn_buckets %d\n", dyn_buckets));
1145
1146 /* Save the current buckets array for later error recovery */
1147 old_dyn_v = ipfw_dyn_v;
1148 old_curr_dyn_buckets = curr_dyn_buckets;
1149
1150 curr_dyn_buckets = dyn_buckets;
1151 for (;;) {
1152 ipfw_dyn_v = kmalloc(curr_dyn_buckets * sizeof(ipfw_dyn_rule *),
1153 M_IPFW, M_NOWAIT | M_ZERO);
1154 if (ipfw_dyn_v != NULL || curr_dyn_buckets <= 2)
1155 break;
1156
1157 curr_dyn_buckets /= 2;
1158 if (curr_dyn_buckets <= old_curr_dyn_buckets &&
1159 old_dyn_v != NULL) {
1160 /*
1161 * Don't try allocating smaller buckets array, reuse
1162 * the old one, which alreay contains enough buckets
1163 */
1164 break;
1165 }
1166 }
1167
1168 if (ipfw_dyn_v != NULL) {
1169 if (old_dyn_v != NULL)
1170 kfree(old_dyn_v, M_IPFW);
1171 } else {
1172 /* Allocation failed, restore old buckets array */
1173 ipfw_dyn_v = old_dyn_v;
1174 curr_dyn_buckets = old_curr_dyn_buckets;
1175 }
1176
1177 if (ipfw_dyn_v != NULL)
1178 ++dyn_buckets_gen;
1179 }
1180
1181 /**
1182 * Install state of type 'type' for a dynamic session.
1183 * The hash table contains two type of rules:
1184 * - regular rules (O_KEEP_STATE)
1185 * - rules for sessions with limited number of sess per user
1186 * (O_LIMIT). When they are created, the parent is
1187 * increased by 1, and decreased on delete. In this case,
1188 * the third parameter is the parent rule and not the chain.
1189 * - "parent" rules for the above (O_LIMIT_PARENT).
1190 */
1191 static ipfw_dyn_rule *
1192 add_dyn_rule(struct ipfw_flow_id *id, uint8_t dyn_type, struct ip_fw *rule)
1193 {
1194 ipfw_dyn_rule *r;
1195 int i;
1196
1197 if (ipfw_dyn_v == NULL ||
1198 (dyn_count == 0 && dyn_buckets != curr_dyn_buckets)) {
1199 realloc_dynamic_table();
1200 if (ipfw_dyn_v == NULL)
1201 return NULL; /* failed ! */
1202 }
1203 i = hash_packet(id);
1204
1205 r = kmalloc(sizeof(*r), M_IPFW, M_NOWAIT | M_ZERO);
1206 if (r == NULL) {
1207 kprintf ("sorry cannot allocate state\n");
1208 return NULL;
1209 }
1210
1211 /* increase refcount on parent, and set pointer */
1212 if (dyn_type == O_LIMIT) {
1213 ipfw_dyn_rule *parent = (ipfw_dyn_rule *)rule;
1214
1215 if (parent->dyn_type != O_LIMIT_PARENT)
1216 panic("invalid parent");
1217 parent->count++;
1218 r->parent = parent;
1219 rule = parent->stub->rule[mycpuid];
1220 KKASSERT(rule->stub == parent->stub);
1221 }
1222 KKASSERT(rule->cpuid == mycpuid && rule->stub != NULL);
1223
1224 r->id = *id;
1225 r->expire = time_second + dyn_syn_lifetime;
1226 r->stub = rule->stub;
1227 r->dyn_type = dyn_type;
1228 r->pcnt = r->bcnt = 0;
1229 r->count = 0;
1230
1231 r->bucket = i;
1232 r->next = ipfw_dyn_v[i];
1233 ipfw_dyn_v[i] = r;
1234 dyn_count++;
1235 dyn_buckets_gen++;
1236 DEB(kprintf("-- add dyn entry ty %d 0x%08x %d -> 0x%08x %d, total %d\n",
1237 dyn_type,
1238 (r->id.src_ip), (r->id.src_port),
1239 (r->id.dst_ip), (r->id.dst_port),
1240 dyn_count );)
1241 return r;
1242 }
1243
1244 /**
1245 * lookup dynamic parent rule using pkt and rule as search keys.
1246 * If the lookup fails, then install one.
1247 */
1248 static ipfw_dyn_rule *
1249 lookup_dyn_parent(struct ipfw_flow_id *pkt, struct ip_fw *rule)
1250 {
1251 ipfw_dyn_rule *q;
1252 int i;
1253
1254 if (ipfw_dyn_v) {
1255 i = hash_packet(pkt);
1256 for (q = ipfw_dyn_v[i]; q != NULL; q = q->next) {
1257 if (q->dyn_type == O_LIMIT_PARENT &&
1258 rule->stub == q->stub &&
1259 pkt->proto == q->id.proto &&
1260 pkt->src_ip == q->id.src_ip &&
1261 pkt->dst_ip == q->id.dst_ip &&
1262 pkt->src_port == q->id.src_port &&
1263 pkt->dst_port == q->id.dst_port) {
1264 q->expire = time_second + dyn_short_lifetime;
1265 DEB(kprintf("lookup_dyn_parent found 0x%p\n",q);)
1266 return q;
1267 }
1268 }
1269 }
1270 return add_dyn_rule(pkt, O_LIMIT_PARENT, rule);
1271 }
1272
1273 /**
1274 * Install dynamic state for rule type cmd->o.opcode
1275 *
1276 * Returns 1 (failure) if state is not installed because of errors or because
1277 * session limitations are enforced.
1278 */
1279 static int
1280 install_state_locked(struct ip_fw *rule, ipfw_insn_limit *cmd,
1281 struct ip_fw_args *args)
1282 {
1283 static int last_log; /* XXX */
1284
1285 ipfw_dyn_rule *q;
1286
1287 DEB(kprintf("-- install state type %d 0x%08x %u -> 0x%08x %u\n",
1288 cmd->o.opcode,
1289 (args->f_id.src_ip), (args->f_id.src_port),
1290 (args->f_id.dst_ip), (args->f_id.dst_port) );)
1291
1292 q = lookup_dyn_rule(&args->f_id, NULL, NULL);
1293 if (q != NULL) { /* should never occur */
1294 if (last_log != time_second) {
1295 last_log = time_second;
1296 kprintf(" install_state: entry already present, done\n");
1297 }
1298 return 0;
1299 }
1300
1301 if (dyn_count >= dyn_max) {
1302 /*
1303 * Run out of slots, try to remove any expired rule.
1304 */
1305 remove_dyn_rule_locked(NULL, (ipfw_dyn_rule *)1);
1306 if (dyn_count >= dyn_max) {
1307 if (last_log != time_second) {
1308 last_log = time_second;
1309 kprintf("install_state: "
1310 "Too many dynamic rules\n");
1311 }
1312 return 1; /* cannot install, notify caller */
1313 }
1314 }
1315
1316 switch (cmd->o.opcode) {
1317 case O_KEEP_STATE: /* bidir rule */
1318 if (add_dyn_rule(&args->f_id, O_KEEP_STATE, rule) == NULL)
1319 return 1;
1320 break;
1321
1322 case O_LIMIT: /* limit number of sessions */
1323 {
1324 uint16_t limit_mask = cmd->limit_mask;
1325 struct ipfw_flow_id id;
1326 ipfw_dyn_rule *parent;
1327
1328 DEB(kprintf("installing dyn-limit rule %d\n",
1329 cmd->conn_limit);)
1330
1331 id.dst_ip = id.src_ip = 0;
1332 id.dst_port = id.src_port = 0;
1333 id.proto = args->f_id.proto;
1334
1335 if (limit_mask & DYN_SRC_ADDR)
1336 id.src_ip = args->f_id.src_ip;
1337 if (limit_mask & DYN_DST_ADDR)
1338 id.dst_ip = args->f_id.dst_ip;
1339 if (limit_mask & DYN_SRC_PORT)
1340 id.src_port = args->f_id.src_port;
1341 if (limit_mask & DYN_DST_PORT)
1342 id.dst_port = args->f_id.dst_port;
1343
1344 parent = lookup_dyn_parent(&id, rule);
1345 if (parent == NULL) {
1346 kprintf("add parent failed\n");
1347 return 1;
1348 }
1349
1350 if (parent->count >= cmd->conn_limit) {
1351 /*
1352 * See if we can remove some expired rule.
1353 */
1354 remove_dyn_rule_locked(rule, parent);
1355 if (parent->count >= cmd->conn_limit) {
1356 if (fw_verbose &&
1357 last_log != time_second) {
1358 last_log = time_second;
1359 log(LOG_SECURITY | LOG_DEBUG,
1360 "drop session, "
1361 "too many entries\n");
1362 }
1363 return 1;
1364 }
1365 }
1366 if (add_dyn_rule(&args->f_id, O_LIMIT,
1367 (struct ip_fw *)parent) == NULL)
1368 return 1;
1369 }
1370 break;
1371 default:
1372 kprintf("unknown dynamic rule type %u\n", cmd->o.opcode);
1373 return 1;
1374 }
1375 lookup_dyn_rule(&args->f_id, NULL, NULL); /* XXX just set lifetime */
1376 return 0;
1377 }
1378
1379 static int
1380 install_state(struct ip_fw *rule, ipfw_insn_limit *cmd,
1381 struct ip_fw_args *args, int *deny)
1382 {
1383 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
1384 uint32_t gen;
1385 int ret = 0;
1386
1387 *deny = 0;
1388 gen = ctx->ipfw_gen;
1389
1390 lockmgr(&dyn_lock, LK_EXCLUSIVE);
1391 if (ctx->ipfw_gen != gen) {
1392 /* See the comment in lookup_rule() */
1393 *deny = 1;
1394 } else {
1395 ret = install_state_locked(rule, cmd, args);
1396 }
1397 lockmgr(&dyn_lock, LK_RELEASE);
1398
1399 return ret;
1400 }
1401
1402 /*
1403 * Transmit a TCP packet, containing either a RST or a keepalive.
1404 * When flags & TH_RST, we are sending a RST packet, because of a
1405 * "reset" action matched the packet.
1406 * Otherwise we are sending a keepalive, and flags & TH_
1407 */
1408 static void
1409 send_pkt(struct ipfw_flow_id *id, uint32_t seq, uint32_t ack, int flags)
1410 {
1411 struct mbuf *m;
1412 struct ip *ip;
1413 struct tcphdr *tcp;
1414 struct route sro; /* fake route */
1415
1416 MGETHDR(m, MB_DONTWAIT, MT_HEADER);
1417 if (m == NULL)
1418 return;
1419 m->m_pkthdr.rcvif = NULL;
1420 m->m_pkthdr.len = m->m_len = sizeof(struct ip) + sizeof(struct tcphdr);
1421 m->m_data += max_linkhdr;
1422
1423 ip = mtod(m, struct ip *);
1424 bzero(ip, m->m_len);
1425 tcp = (struct tcphdr *)(ip + 1); /* no IP options */
1426 ip->ip_p = IPPROTO_TCP;
1427 tcp->th_off = 5;
1428
1429 /*
1430 * Assume we are sending a RST (or a keepalive in the reverse
1431 * direction), swap src and destination addresses and ports.
1432 */
1433 ip->ip_src.s_addr = htonl(id->dst_ip);
1434 ip->ip_dst.s_addr = htonl(id->src_ip);
1435 tcp->th_sport = htons(id->dst_port);
1436 tcp->th_dport = htons(id->src_port);
1437 if (flags & TH_RST) { /* we are sending a RST */
1438 if (flags & TH_ACK) {
1439 tcp->th_seq = htonl(ack);
1440 tcp->th_ack = htonl(0);
1441 tcp->th_flags = TH_RST;
1442 } else {
1443 if (flags & TH_SYN)
1444 seq++;
1445 tcp->th_seq = htonl(0);
1446 tcp->th_ack = htonl(seq);
1447 tcp->th_flags = TH_RST | TH_ACK;
1448 }
1449 } else {
1450 /*
1451 * We are sending a keepalive. flags & TH_SYN determines
1452 * the direction, forward if set, reverse if clear.
1453 * NOTE: seq and ack are always assumed to be correct
1454 * as set by the caller. This may be confusing...
1455 */
1456 if (flags & TH_SYN) {
1457 /*
1458 * we have to rewrite the correct addresses!
1459 */
1460 ip->ip_dst.s_addr = htonl(id->dst_ip);
1461 ip->ip_src.s_addr = htonl(id->src_ip);
1462 tcp->th_dport = htons(id->dst_port);
1463 tcp->th_sport = htons(id->src_port);
1464 }
1465 tcp->th_seq = htonl(seq);
1466 tcp->th_ack = htonl(ack);
1467 tcp->th_flags = TH_ACK;
1468 }
1469
1470 /*
1471 * set ip_len to the payload size so we can compute
1472 * the tcp checksum on the pseudoheader
1473 * XXX check this, could save a couple of words ?
1474 */
1475 ip->ip_len = htons(sizeof(struct tcphdr));
1476 tcp->th_sum = in_cksum(m, m->m_pkthdr.len);
1477
1478 /*
1479 * now fill fields left out earlier
1480 */
1481 ip->ip_ttl = ip_defttl;
1482 ip->ip_len = m->m_pkthdr.len;
1483
1484 bzero(&sro, sizeof(sro));
1485 ip_rtaddr(ip->ip_dst, &sro);
1486
1487 m->m_pkthdr.fw_flags |= IPFW_MBUF_GENERATED;
1488 ip_output(m, NULL, &sro, 0, NULL, NULL);
1489 if (sro.ro_rt)
1490 RTFREE(sro.ro_rt);
1491 }
1492
1493 /*
1494 * sends a reject message, consuming the mbuf passed as an argument.
1495 */
1496 static void
1497 send_reject(struct ip_fw_args *args, int code, int offset, int ip_len)
1498 {
1499 if (code != ICMP_REJECT_RST) { /* Send an ICMP unreach */
1500 /* We need the IP header in host order for icmp_error(). */
1501 if (args->eh != NULL) {
1502 struct ip *ip = mtod(args->m, struct ip *);
1503
1504 ip->ip_len = ntohs(ip->ip_len);
1505 ip->ip_off = ntohs(ip->ip_off);
1506 }
1507 icmp_error(args->m, ICMP_UNREACH, code, 0L, 0);
1508 } else if (offset == 0 && args->f_id.proto == IPPROTO_TCP) {
1509 struct tcphdr *const tcp =
1510 L3HDR(struct tcphdr, mtod(args->m, struct ip *));
1511
1512 if ((tcp->th_flags & TH_RST) == 0) {
1513 send_pkt(&args->f_id, ntohl(tcp->th_seq),
1514 ntohl(tcp->th_ack), tcp->th_flags | TH_RST);
1515 }
1516 m_freem(args->m);
1517 } else {
1518 m_freem(args->m);
1519 }
1520 args->m = NULL;
1521 }
1522
1523 /**
1524 *
1525 * Given an ip_fw *, lookup_next_rule will return a pointer
1526 * to the next rule, which can be either the jump
1527 * target (for skipto instructions) or the next one in the list (in
1528 * all other cases including a missing jump target).
1529 * The result is also written in the "next_rule" field of the rule.
1530 * Backward jumps are not allowed, so start looking from the next
1531 * rule...
1532 *
1533 * This never returns NULL -- in case we do not have an exact match,
1534 * the next rule is returned. When the ruleset is changed,
1535 * pointers are flushed so we are always correct.
1536 */
1537
1538 static struct ip_fw *
1539 lookup_next_rule(struct ip_fw *me)
1540 {
1541 struct ip_fw *rule = NULL;
1542 ipfw_insn *cmd;
1543
1544 /* look for action, in case it is a skipto */
1545 cmd = ACTION_PTR(me);
1546 if (cmd->opcode == O_LOG)
1547 cmd += F_LEN(cmd);
1548 if (cmd->opcode == O_SKIPTO) {
1549 for (rule = me->next; rule; rule = rule->next) {
1550 if (rule->rulenum >= cmd->arg1)
1551 break;
1552 }
1553 }
1554 if (rule == NULL) /* failure or not a skipto */
1555 rule = me->next;
1556 me->next_rule = rule;
1557 return rule;
1558 }
1559
1560 /*
1561 * The main check routine for the firewall.
1562 *
1563 * All arguments are in args so we can modify them and return them
1564 * back to the caller.
1565 *
1566 * Parameters:
1567 *
1568 * args->m (in/out) The packet; we set to NULL when/if we nuke it.
1569 * Starts with the IP header.
1570 * args->eh (in) Mac header if present, or NULL for layer3 packet.
1571 * args->oif Outgoing interface, or NULL if packet is incoming.
1572 * The incoming interface is in the mbuf. (in)
1573 *
1574 * args->rule Pointer to the last matching rule (in/out)
1575 * args->f_id Addresses grabbed from the packet (out)
1576 *
1577 * Return value:
1578 *
1579 * IP_FW_PORT_DENY_FLAG the packet must be dropped.
1580 * 0 The packet is to be accepted and routed normally OR
1581 * the packet was denied/rejected and has been dropped;
1582 * in the latter case, *m is equal to NULL upon return.
1583 * port Divert the packet to port, with these caveats:
1584 *
1585 * - If IP_FW_PORT_TEE_FLAG is set, tee the packet instead
1586 * of diverting it (ie, 'ipfw tee').
1587 *
1588 * - If IP_FW_PORT_DYNT_FLAG is set, interpret the lower
1589 * 16 bits as a dummynet pipe number instead of diverting
1590 */
1591
1592 static int
1593 ipfw_chk(struct ip_fw_args *args)
1594 {
1595 /*
1596 * Local variables hold state during the processing of a packet.
1597 *
1598 * IMPORTANT NOTE: to speed up the processing of rules, there
1599 * are some assumption on the values of the variables, which
1600 * are documented here. Should you change them, please check
1601 * the implementation of the various instructions to make sure
1602 * that they still work.
1603 *
1604 * args->eh The MAC header. It is non-null for a layer2
1605 * packet, it is NULL for a layer-3 packet.
1606 *
1607 * m | args->m Pointer to the mbuf, as received from the caller.
1608 * It may change if ipfw_chk() does an m_pullup, or if it
1609 * consumes the packet because it calls send_reject().
1610 * XXX This has to change, so that ipfw_chk() never modifies
1611 * or consumes the buffer.
1612 * ip is simply an alias of the value of m, and it is kept
1613 * in sync with it (the packet is supposed to start with
1614 * the ip header).
1615 */
1616 struct mbuf *m = args->m;
1617 struct ip *ip = mtod(m, struct ip *);
1618
1619 /*
1620 * oif | args->oif If NULL, ipfw_chk has been called on the
1621 * inbound path (ether_input, ip_input).
1622 * If non-NULL, ipfw_chk has been called on the outbound path
1623 * (ether_output, ip_output).
1624 */
1625 struct ifnet *oif = args->oif;
1626
1627 struct ip_fw *f = NULL; /* matching rule */
1628 int retval = 0;
1629 struct m_tag *mtag;
1630
1631 /*
1632 * hlen The length of the IPv4 header.
1633 * hlen >0 means we have an IPv4 packet.
1634 */
1635 u_int hlen = 0; /* hlen >0 means we have an IP pkt */
1636
1637 /*
1638 * offset The offset of a fragment. offset != 0 means that
1639 * we have a fragment at this offset of an IPv4 packet.
1640 * offset == 0 means that (if this is an IPv4 packet)
1641 * this is the first or only fragment.
1642 */
1643 u_short offset = 0;
1644
1645 /*
1646 * Local copies of addresses. They are only valid if we have
1647 * an IP packet.
1648 *
1649 * proto The protocol. Set to 0 for non-ip packets,
1650 * or to the protocol read from the packet otherwise.
1651 * proto != 0 means that we have an IPv4 packet.
1652 *
1653 * src_port, dst_port port numbers, in HOST format. Only
1654 * valid for TCP and UDP packets.
1655 *
1656 * src_ip, dst_ip ip addresses, in NETWORK format.
1657 * Only valid for IPv4 packets.
1658 */
1659 uint8_t proto;
1660 uint16_t src_port = 0, dst_port = 0; /* NOTE: host format */
1661 struct in_addr src_ip, dst_ip; /* NOTE: network format */
1662 uint16_t ip_len = 0;
1663
1664 /*
1665 * dyn_dir = MATCH_UNKNOWN when rules unchecked,
1666 * MATCH_NONE when checked and not matched (dyn_f = NULL),
1667 * MATCH_FORWARD or MATCH_REVERSE otherwise (dyn_f != NULL)
1668 */
1669 int dyn_dir = MATCH_UNKNOWN;
1670 struct ip_fw *dyn_f = NULL;
1671 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
1672
1673 if (m->m_pkthdr.fw_flags & IPFW_MBUF_GENERATED)
1674 return 0; /* accept */
1675
1676 if (args->eh == NULL || /* layer 3 packet */
1677 (m->m_pkthdr.len >= sizeof(struct ip) &&
1678 ntohs(args->eh->ether_type) == ETHERTYPE_IP))
1679 hlen = ip->ip_hl << 2;
1680
1681 /*
1682 * Collect parameters into local variables for faster matching.
1683 */
1684 if (hlen == 0) { /* do not grab addresses for non-ip pkts */
1685 proto = args->f_id.proto = 0; /* mark f_id invalid */
1686 goto after_ip_checks;
1687 }
1688
1689 proto = args->f_id.proto = ip->ip_p;
1690 src_ip = ip->ip_src;
1691 dst_ip = ip->ip_dst;
1692 if (args->eh != NULL) { /* layer 2 packets are as on the wire */
1693 offset = ntohs(ip->ip_off) & IP_OFFMASK;
1694 ip_len = ntohs(ip->ip_len);
1695 } else {
1696 offset = ip->ip_off & IP_OFFMASK;
1697 ip_len = ip->ip_len;
1698 }
1699
1700 #define PULLUP_TO(len) \
1701 do { \
1702 if (m->m_len < (len)) { \
1703 args->m = m = m_pullup(m, (len));\
1704 if (m == NULL) \
1705 goto pullup_failed; \
1706 ip = mtod(m, struct ip *); \
1707 } \
1708 } while (0)
1709
1710 if (offset == 0) {
1711 switch (proto) {
1712 case IPPROTO_TCP:
1713 {
1714 struct tcphdr *tcp;
1715
1716 PULLUP_TO(hlen + sizeof(struct tcphdr));
1717 tcp = L3HDR(struct tcphdr, ip);
1718 dst_port = tcp->th_dport;
1719 src_port = tcp->th_sport;
1720 args->f_id.flags = tcp->th_flags;
1721 }
1722 break;
1723
1724 case IPPROTO_UDP:
1725 {
1726 struct udphdr *udp;
1727
1728 PULLUP_TO(hlen + sizeof(struct udphdr));
1729 udp = L3HDR(struct udphdr, ip);
1730 dst_port = udp->uh_dport;
1731 src_port = udp->uh_sport;
1732 }
1733 break;
1734
1735 case IPPROTO_ICMP:
1736 PULLUP_TO(hlen + 4); /* type, code and checksum. */
1737 args->f_id.flags = L3HDR(struct icmp, ip)->icmp_type;
1738 break;
1739
1740 default:
1741 break;
1742 }
1743 }
1744
1745 #undef PULLUP_TO
1746
1747 args->f_id.src_ip = ntohl(src_ip.s_addr);
1748 args->f_id.dst_ip = ntohl(dst_ip.s_addr);
1749 args->f_id.src_port = src_port = ntohs(src_port);
1750 args->f_id.dst_port = dst_port = ntohs(dst_port);
1751
1752 after_ip_checks:
1753 if (args->rule) {
1754 /*
1755 * Packet has already been tagged. Look for the next rule
1756 * to restart processing.
1757 *
1758 * If fw_one_pass != 0 then just accept it.
1759 * XXX should not happen here, but optimized out in
1760 * the caller.
1761 */
1762 if (fw_one_pass)
1763 return 0;
1764
1765 /* This rule is being/has been flushed */
1766 if (ipfw_flushing)
1767 return IP_FW_PORT_DENY_FLAG;
1768
1769 KASSERT(args->rule->cpuid == mycpuid,
1770 ("rule used on cpu%d\n", mycpuid));
1771
1772 /* This rule was deleted */
1773 if (args->rule->rule_flags & IPFW_RULE_F_INVALID)
1774 return IP_FW_PORT_DENY_FLAG;
1775
1776 f = args->rule->next_rule;
1777 if (f == NULL)
1778 f = lookup_next_rule(args->rule);
1779 } else {
1780 /*
1781 * Find the starting rule. It can be either the first
1782 * one, or the one after divert_rule if asked so.
1783 */
1784 int skipto;
1785
1786 mtag = m_tag_find(m, PACKET_TAG_IPFW_DIVERT, NULL);
1787 if (mtag != NULL)
1788 skipto = *(uint16_t *)m_tag_data(mtag);
1789 else
1790 skipto = 0;
1791
1792 f = ctx->ipfw_layer3_chain;
1793 if (args->eh == NULL && skipto != 0) {
1794 /* No skipto during rule flushing */
1795 if (ipfw_flushing)
1796 return IP_FW_PORT_DENY_FLAG;
1797
1798 if (skipto >= IPFW_DEFAULT_RULE)
1799 return(IP_FW_PORT_DENY_FLAG); /* invalid */
1800
1801 while (f && f->rulenum <= skipto)
1802 f = f->next;
1803 if (f == NULL) /* drop packet */
1804 return(IP_FW_PORT_DENY_FLAG);
1805 } else if (ipfw_flushing) {
1806 /* Rules are being flushed; skip to default rule */
1807 f = ctx->ipfw_default_rule;
1808 }
1809 }
1810 if ((mtag = m_tag_find(m, PACKET_TAG_IPFW_DIVERT, NULL)) != NULL)
1811 m_tag_delete(m, mtag);
1812
1813 /*
1814 * Now scan the rules, and parse microinstructions for each rule.
1815 */
1816 for (; f; f = f->next) {
1817 int l, cmdlen;
1818 ipfw_insn *cmd;
1819 int skip_or; /* skip rest of OR block */
1820
1821 again:
1822 if (ctx->ipfw_set_disable & (1 << f->set))
1823 continue;
1824
1825 skip_or = 0;
1826 for (l = f->cmd_len, cmd = f->cmd; l > 0;
1827 l -= cmdlen, cmd += cmdlen) {
1828 int match, deny;
1829
1830 /*
1831 * check_body is a jump target used when we find a
1832 * CHECK_STATE, and need to jump to the body of
1833 * the target rule.
1834 */
1835
1836 check_body:
1837 cmdlen = F_LEN(cmd);
1838 /*
1839 * An OR block (insn_1 || .. || insn_n) has the
1840 * F_OR bit set in all but the last instruction.
1841 * The first match will set "skip_or", and cause
1842 * the following instructions to be skipped until
1843 * past the one with the F_OR bit clear.
1844 */
1845 if (skip_or) { /* skip this instruction */
1846 if ((cmd->len & F_OR) == 0)
1847 skip_or = 0; /* next one is good */
1848 continue;
1849 }
1850 match = 0; /* set to 1 if we succeed */
1851
1852 switch (cmd->opcode) {
1853 /*
1854 * The first set of opcodes compares the packet's
1855 * fields with some pattern, setting 'match' if a
1856 * match is found. At the end of the loop there is
1857 * logic to deal with F_NOT and F_OR flags associated
1858 * with the opcode.
1859 */
1860 case O_NOP:
1861 match = 1;
1862 break;
1863
1864 case O_FORWARD_MAC:
1865 kprintf("ipfw: opcode %d unimplemented\n",
1866 cmd->opcode);
1867 break;
1868
1869 case O_GID:
1870 case O_UID:
1871 /*
1872 * We only check offset == 0 && proto != 0,
1873 * as this ensures that we have an IPv4
1874 * packet with the ports info.
1875 */
1876 if (offset!=0)
1877 break;
1878 {
1879 struct inpcbinfo *pi;
1880 int wildcard;
1881 struct inpcb *pcb;
1882
1883 if (proto == IPPROTO_TCP) {
1884 wildcard = 0;
1885 pi = &tcbinfo[mycpu->gd_cpuid];
1886 } else if (proto == IPPROTO_UDP) {
1887 wildcard = 1;
1888 pi = &udbinfo;
1889 } else
1890 break;
1891
1892 pcb = (oif) ?
1893 in_pcblookup_hash(pi,
1894 dst_ip, htons(dst_port),
1895 src_ip, htons(src_port),
1896 wildcard, oif) :
1897 in_pcblookup_hash(pi,
1898 src_ip, htons(src_port),
1899 dst_ip, htons(dst_port),
1900 wildcard, NULL);
1901
1902 if (pcb == NULL || pcb->inp_socket == NULL)
1903 break;
1904
1905 if (cmd->opcode == O_UID) {
1906 #define socheckuid(a,b) ((a)->so_cred->cr_uid != (b))
1907 match =
1908 !socheckuid(pcb->inp_socket,
1909 (uid_t)((ipfw_insn_u32 *)cmd)->d[0]);
1910 #undef socheckuid
1911 } else {
1912 match = groupmember(
1913 (uid_t)((ipfw_insn_u32 *)cmd)->d[0],
1914 pcb->inp_socket->so_cred);
1915 }
1916 }
1917 break;
1918
1919 case O_RECV:
1920 match = iface_match(m->m_pkthdr.rcvif,
1921 (ipfw_insn_if *)cmd);
1922 break;
1923
1924 case O_XMIT:
1925 match = iface_match(oif, (ipfw_insn_if *)cmd);
1926 break;
1927
1928 case O_VIA:
1929 match = iface_match(oif ? oif :
1930 m->m_pkthdr.rcvif, (ipfw_insn_if *)cmd);
1931 break;
1932
1933 case O_MACADDR2:
1934 if (args->eh != NULL) { /* have MAC header */
1935 uint32_t *want = (uint32_t *)
1936 ((ipfw_insn_mac *)cmd)->addr;
1937 uint32_t *mask = (uint32_t *)
1938 ((ipfw_insn_mac *)cmd)->mask;
1939 uint32_t *hdr = (uint32_t *)args->eh;
1940
1941 match =
1942 (want[0] == (hdr[0] & mask[0]) &&
1943 want[1] == (hdr[1] & mask[1]) &&
1944 want[2] == (hdr[2] & mask[2]));
1945 }
1946 break;
1947
1948 case O_MAC_TYPE:
1949 if (args->eh != NULL) {
1950 uint16_t t =
1951 ntohs(args->eh->ether_type);
1952 uint16_t *p =
1953 ((ipfw_insn_u16 *)cmd)->ports;
1954 int i;
1955
1956 /* Special vlan handling */
1957 if (m->m_flags & M_VLANTAG)
1958 t = ETHERTYPE_VLAN;
1959
1960 for (i = cmdlen - 1; !match && i > 0;
1961 i--, p += 2) {
1962 match =
1963 (t >= p[0] && t <= p[1]);
1964 }
1965 }
1966 break;
1967
1968 case O_FRAG:
1969 match = (hlen > 0 && offset != 0);
1970 break;
1971
1972 case O_IN: /* "out" is "not in" */
1973 match = (oif == NULL);
1974 break;
1975
1976 case O_LAYER2:
1977 match = (args->eh != NULL);
1978 break;
1979
1980 case O_PROTO:
1981 /*
1982 * We do not allow an arg of 0 so the
1983 * check of "proto" only suffices.
1984 */
1985 match = (proto == cmd->arg1);
1986 break;
1987
1988 case O_IP_SRC:
1989 match = (hlen > 0 &&
1990 ((ipfw_insn_ip *)cmd)->addr.s_addr ==
1991 src_ip.s_addr);
1992 break;
1993
1994 case O_IP_SRC_MASK:
1995 match = (hlen > 0 &&
1996 ((ipfw_insn_ip *)cmd)->addr.s_addr ==
1997 (src_ip.s_addr &
1998 ((ipfw_insn_ip *)cmd)->mask.s_addr));
1999 break;
2000
2001 case O_IP_SRC_ME:
2002 if (hlen > 0) {
2003 struct ifnet *tif;
2004
2005 tif = INADDR_TO_IFP(&src_ip);
2006 match = (tif != NULL);
2007 }
2008 break;
2009
2010 case O_IP_DST_SET:
2011 case O_IP_SRC_SET:
2012 if (hlen > 0) {
2013 uint32_t *d = (uint32_t *)(cmd + 1);
2014 uint32_t addr =
2015 cmd->opcode == O_IP_DST_SET ?
2016 args->f_id.dst_ip :
2017 args->f_id.src_ip;
2018
2019 if (addr < d[0])
2020 break;
2021 addr -= d[0]; /* subtract base */
2022 match =
2023 (addr < cmd->arg1) &&
2024 (d[1 + (addr >> 5)] &
2025 (1 << (addr & 0x1f)));
2026 }
2027 break;
2028
2029 case O_IP_DST:
2030 match = (hlen > 0 &&
2031 ((ipfw_insn_ip *)cmd)->addr.s_addr ==
2032 dst_ip.s_addr);
2033 break;
2034
2035 case O_IP_DST_MASK:
2036 match = (hlen > 0) &&
2037 (((ipfw_insn_ip *)cmd)->addr.s_addr ==
2038 (dst_ip.s_addr &
2039 ((ipfw_insn_ip *)cmd)->mask.s_addr));
2040 break;
2041
2042 case O_IP_DST_ME:
2043 if (hlen > 0) {
2044 struct ifnet *tif;
2045
2046 tif = INADDR_TO_IFP(&dst_ip);
2047 match = (tif != NULL);
2048 }
2049 break;
2050
2051 case O_IP_SRCPORT:
2052 case O_IP_DSTPORT:
2053 /*
2054 * offset == 0 && proto != 0 is enough
2055 * to guarantee that we have an IPv4
2056 * packet with port info.
2057 */
2058 if ((proto==IPPROTO_UDP || proto==IPPROTO_TCP)
2059 && offset == 0) {
2060 uint16_t x =
2061 (cmd->opcode == O_IP_SRCPORT) ?
2062 src_port : dst_port ;
2063 uint16_t *p =
2064 ((ipfw_insn_u16 *)cmd)->ports;
2065 int i;
2066
2067 for (i = cmdlen - 1; !match && i > 0;
2068 i--, p += 2) {
2069 match =
2070 (x >= p[0] && x <= p[1]);
2071 }
2072 }
2073 break;
2074
2075 case O_ICMPTYPE:
2076 match = (offset == 0 && proto==IPPROTO_ICMP &&
2077 icmptype_match(ip, (ipfw_insn_u32 *)cmd));
2078 break;
2079
2080 case O_IPOPT:
2081 match = (hlen > 0 && ipopts_match(ip, cmd));
2082 break;
2083
2084 case O_IPVER:
2085 match = (hlen > 0 && cmd->arg1 == ip->ip_v);
2086 break;
2087
2088 case O_IPTTL:
2089 match = (hlen > 0 && cmd->arg1 == ip->ip_ttl);
2090 break;
2091
2092 case O_IPID:
2093 match = (hlen > 0 &&
2094 cmd->arg1 == ntohs(ip->ip_id));
2095 break;
2096
2097 case O_IPLEN:
2098 match = (hlen > 0 && cmd->arg1 == ip_len);
2099 break;
2100
2101 case O_IPPRECEDENCE:
2102 match = (hlen > 0 &&
2103 (cmd->arg1 == (ip->ip_tos & 0xe0)));
2104 break;
2105
2106 case O_IPTOS:
2107 match = (hlen > 0 &&
2108 flags_match(cmd, ip->ip_tos));
2109 break;
2110
2111 case O_TCPFLAGS:
2112 match = (proto == IPPROTO_TCP && offset == 0 &&
2113 flags_match(cmd,
2114 L3HDR(struct tcphdr,ip)->th_flags));
2115 break;
2116
2117 case O_TCPOPTS:
2118 match = (proto == IPPROTO_TCP && offset == 0 &&
2119 tcpopts_match(ip, cmd));
2120 break;
2121
2122 case O_TCPSEQ:
2123 match = (proto == IPPROTO_TCP && offset == 0 &&
2124 ((ipfw_insn_u32 *)cmd)->d[0] ==
2125 L3HDR(struct tcphdr,ip)->th_seq);
2126 break;
2127
2128 case O_TCPACK:
2129 match = (proto == IPPROTO_TCP && offset == 0 &&
2130 ((ipfw_insn_u32 *)cmd)->d[0] ==
2131 L3HDR(struct tcphdr,ip)->th_ack);
2132 break;
2133
2134 case O_TCPWIN:
2135 match = (proto == IPPROTO_TCP && offset == 0 &&
2136 cmd->arg1 ==
2137 L3HDR(struct tcphdr,ip)->th_win);
2138 break;
2139
2140 case O_ESTAB:
2141 /* reject packets which have SYN only */
2142 /* XXX should i also check for TH_ACK ? */
2143 match = (proto == IPPROTO_TCP && offset == 0 &&
2144 (L3HDR(struct tcphdr,ip)->th_flags &
2145 (TH_RST | TH_ACK | TH_SYN)) != TH_SYN);
2146 break;
2147
2148 case O_LOG:
2149 if (fw_verbose)
2150 ipfw_log(f, hlen, args->eh, m, oif);
2151 match = 1;
2152 break;
2153
2154 case O_PROB:
2155 match = (krandom() <
2156 ((ipfw_insn_u32 *)cmd)->d[0]);
2157 break;
2158
2159 /*
2160 * The second set of opcodes represents 'actions',
2161 * i.e. the terminal part of a rule once the packet
2162 * matches all previous patterns.
2163 * Typically there is only one action for each rule,
2164 * and the opcode is stored at the end of the rule
2165 * (but there are exceptions -- see below).
2166 *
2167 * In general, here we set retval and terminate the
2168 * outer loop (would be a 'break 3' in some language,
2169 * but we need to do a 'goto done').
2170 *
2171 * Exceptions:
2172 * O_COUNT and O_SKIPTO actions:
2173 * instead of terminating, we jump to the next rule
2174 * ('goto next_rule', equivalent to a 'break 2'),
2175 * or to the SKIPTO target ('goto again' after
2176 * having set f, cmd and l), respectively.
2177 *
2178 * O_LIMIT and O_KEEP_STATE: these opcodes are
2179 * not real 'actions', and are stored right
2180 * before the 'action' part of the rule.
2181 * These opcodes try to install an entry in the
2182 * state tables; if successful, we continue with
2183 * the next opcode (match=1; break;), otherwise
2184 * the packet must be dropped ('goto done' after
2185 * setting retval). If static rules are changed
2186 * during the state installation, the packet will
2187 * be dropped ('return IP_FW_PORT_DENY_FLAG').
2188 *
2189 * O_PROBE_STATE and O_CHECK_STATE: these opcodes
2190 * cause a lookup of the state table, and a jump
2191 * to the 'action' part of the parent rule
2192 * ('goto check_body') if an entry is found, or
2193 * (CHECK_STATE only) a jump to the next rule if
2194 * the entry is not found ('goto next_rule').
2195 * The result of the lookup is cached to make
2196 * further instances of these opcodes are
2197 * effectively NOPs. If static rules are changed
2198 * during the state looking up, the packet will
2199 * be dropped ('return IP_FW_PORT_DENY_FLAG').
2200 */
2201 case O_LIMIT:
2202 case O_KEEP_STATE:
2203 if (!(f->rule_flags & IPFW_RULE_F_STATE)) {
2204 kprintf("%s rule (%d) is not ready "
2205 "on cpu%d\n",
2206 cmd->opcode == O_LIMIT ?
2207 "limit" : "keep state",
2208 f->rulenum, f->cpuid);
2209 goto next_rule;
2210 }
2211 if (install_state(f,
2212 (ipfw_insn_limit *)cmd, args, &deny)) {
2213 if (deny)
2214 return IP_FW_PORT_DENY_FLAG;
2215
2216 retval = IP_FW_PORT_DENY_FLAG;
2217 goto done; /* error/limit violation */
2218 }
2219 if (deny)
2220 return IP_FW_PORT_DENY_FLAG;
2221 match = 1;
2222 break;
2223
2224 case O_PROBE_STATE:
2225 case O_CHECK_STATE:
2226 /*
2227 * dynamic rules are checked at the first
2228 * keep-state or check-state occurrence,
2229 * with the result being stored in dyn_dir.
2230 * The compiler introduces a PROBE_STATE
2231 * instruction for us when we have a
2232 * KEEP_STATE (because PROBE_STATE needs
2233 * to be run first).
2234 */
2235 if (dyn_dir == MATCH_UNKNOWN) {
2236 dyn_f = lookup_rule(&args->f_id,
2237 &dyn_dir,
2238 proto == IPPROTO_TCP ?
2239 L3HDR(struct tcphdr, ip) : NULL,
2240 ip_len, &deny);
2241 if (deny)
2242 return IP_FW_PORT_DENY_FLAG;
2243 if (dyn_f != NULL) {
2244 /*
2245 * Found a rule from a dynamic
2246 * entry; jump to the 'action'
2247 * part of the rule.
2248 */
2249 f = dyn_f;
2250 cmd = ACTION_PTR(f);
2251 l = f->cmd_len - f->act_ofs;
2252 goto check_body;
2253 }
2254 }
2255 /*
2256 * Dynamic entry not found. If CHECK_STATE,
2257 * skip to next rule, if PROBE_STATE just
2258 * ignore and continue with next opcode.
2259 */
2260 if (cmd->opcode == O_CHECK_STATE)
2261 goto next_rule;
2262 else if (!(f->rule_flags & IPFW_RULE_F_STATE))
2263 goto next_rule; /* not ready yet */
2264 match = 1;
2265 break;
2266
2267 case O_ACCEPT:
2268 retval = 0; /* accept */
2269 goto done;
2270
2271 case O_PIPE:
2272 case O_QUEUE:
2273 args->rule = f; /* report matching rule */
2274 retval = cmd->arg1 | IP_FW_PORT_DYNT_FLAG;
2275 goto done;
2276
2277 case O_DIVERT:
2278 case O_TEE:
2279 if (args->eh) /* not on layer 2 */
2280 break;
2281
2282 mtag = m_tag_get(PACKET_TAG_IPFW_DIVERT,
2283 sizeof(uint16_t), MB_DONTWAIT);
2284 if (mtag == NULL) {
2285 retval = IP_FW_PORT_DENY_FLAG;
2286 goto done;
2287 }
2288 *(uint16_t *)m_tag_data(mtag) = f->rulenum;
2289 m_tag_prepend(m, mtag);
2290 retval = (cmd->opcode == O_DIVERT) ?
2291 cmd->arg1 :
2292 cmd->arg1 | IP_FW_PORT_TEE_FLAG;
2293 goto done;
2294
2295 case O_COUNT:
2296 case O_SKIPTO:
2297 f->pcnt++; /* update stats */
2298 f->bcnt += ip_len;
2299 f->timestamp = time_second;
2300 if (cmd->opcode == O_COUNT)
2301 goto next_rule;
2302 /* handle skipto */
2303 if (f->next_rule == NULL)
2304 lookup_next_rule(f);
2305 f = f->next_rule;
2306 goto again;
2307
2308 case O_REJECT:
2309 /*
2310 * Drop the packet and send a reject notice
2311 * if the packet is not ICMP (or is an ICMP
2312 * query), and it is not multicast/broadcast.
2313 */
2314 if (hlen > 0 &&
2315 (proto != IPPROTO_ICMP ||
2316 is_icmp_query(ip)) &&
2317 !(m->m_flags & (M_BCAST|M_MCAST)) &&
2318 !IN_MULTICAST(ntohl(dst_ip.s_addr))) {
2319 /*
2320 * Update statistics before the possible
2321 * blocking 'send_reject'
2322 */
2323 f->pcnt++;
2324 f->bcnt += ip_len;
2325 f->timestamp = time_second;
2326
2327 send_reject(args, cmd->arg1,
2328 offset,ip_len);
2329 m = args->m;
2330
2331 /*
2332 * Return directly here, rule stats
2333 * have been updated above.
2334 */
2335 return IP_FW_PORT_DENY_FLAG;
2336 }
2337 /* FALLTHROUGH */
2338 case O_DENY:
2339 retval = IP_FW_PORT_DENY_FLAG;
2340 goto done;
2341
2342 case O_FORWARD_IP:
2343 if (args->eh) /* not valid on layer2 pkts */
2344 break;
2345 if (!dyn_f || dyn_dir == MATCH_FORWARD) {
2346 struct sockaddr_in *sin;
2347
2348 mtag = m_tag_get(PACKET_TAG_IPFORWARD,
2349 sizeof(*sin), MB_DONTWAIT);
2350 if (mtag == NULL) {
2351 retval = IP_FW_PORT_DENY_FLAG;
2352 goto done;
2353 }
2354 sin = m_tag_data(mtag);
2355
2356 /* Structure copy */
2357 *sin = ((ipfw_insn_sa *)cmd)->sa;
2358
2359 m_tag_prepend(m, mtag);
2360 m->m_pkthdr.fw_flags |=
2361 IPFORWARD_MBUF_TAGGED;
2362 }
2363 retval = 0;
2364 goto done;
2365
2366 default:
2367 panic("-- unknown opcode %d\n", cmd->opcode);
2368 } /* end of switch() on opcodes */
2369
2370 if (cmd->len & F_NOT)
2371 match = !match;
2372
2373 if (match) {
2374 if (cmd->len & F_OR)
2375 skip_or = 1;
2376 } else {
2377 if (!(cmd->len & F_OR)) /* not an OR block, */
2378 break; /* try next rule */
2379 }
2380
2381 } /* end of inner for, scan opcodes */
2382
2383 next_rule:; /* try next rule */
2384
2385 } /* end of outer for, scan rules */
2386 kprintf("+++ ipfw: ouch!, skip past end of rules, denying packet\n");
2387 return(IP_FW_PORT_DENY_FLAG);
2388
2389 done:
2390 /* Update statistics */
2391 f->pcnt++;
2392 f->bcnt += ip_len;
2393 f->timestamp = time_second;
2394 return retval;
2395
2396 pullup_failed:
2397 if (fw_verbose)
2398 kprintf("pullup failed\n");
2399 return(IP_FW_PORT_DENY_FLAG);
2400 }
2401
2402 static void
2403 ipfw_dummynet_io(struct mbuf *m, int pipe_nr, int dir, struct ip_fw_args *fwa)
2404 {
2405 struct m_tag *mtag;
2406 struct dn_pkt *pkt;
2407 ipfw_insn *cmd;
2408 const struct ipfw_flow_id *id;
2409 struct dn_flow_id *fid;
2410
2411 M_ASSERTPKTHDR(m);
2412
2413 mtag = m_tag_get(PACKET_TAG_DUMMYNET, sizeof(*pkt), MB_DONTWAIT);
2414 if (mtag == NULL) {
2415 m_freem(m);
2416 return;
2417 }
2418 m_tag_prepend(m, mtag);
2419
2420 pkt = m_tag_data(mtag);
2421 bzero(pkt, sizeof(*pkt));
2422
2423 cmd = fwa->rule->cmd + fwa->rule->act_ofs;
2424 if (cmd->opcode == O_LOG)
2425 cmd += F_LEN(cmd);
2426 KASSERT(cmd->opcode == O_PIPE || cmd->opcode == O_QUEUE,
2427 ("Rule is not PIPE or QUEUE, opcode %d\n", cmd->opcode));
2428
2429 pkt->dn_m = m;
2430 pkt->dn_flags = (dir & DN_FLAGS_DIR_MASK);
2431 pkt->ifp = fwa->oif;
2432 pkt->cpuid = mycpu->gd_cpuid;
2433 pkt->pipe_nr = pipe_nr;
2434
2435 id = &fwa->f_id;
2436 fid = &pkt->id;
2437 fid->fid_dst_ip = id->dst_ip;
2438 fid->fid_src_ip = id->src_ip;
2439 fid->fid_dst_port = id->dst_port;
2440 fid->fid_src_port = id->src_port;
2441 fid->fid_proto = id->proto;
2442 fid->fid_flags = id->flags;
2443
2444 ipfw_ref_rule(fwa->rule);
2445 pkt->dn_priv = fwa->rule;
2446 pkt->dn_unref_priv = ipfw_unref_rule;
2447
2448 if (cmd->opcode == O_PIPE)
2449 pkt->dn_flags |= DN_FLAGS_IS_PIPE;
2450
2451 if (dir == DN_TO_IP_OUT) {
2452 /*
2453 * We need to copy *ro because for ICMP pkts (and maybe
2454 * others) the caller passed a pointer into the stack;
2455 * dst might also be a pointer into *ro so it needs to
2456 * be updated.
2457 */
2458 pkt->ro = *(fwa->ro);
2459 if (fwa->ro->ro_rt)
2460 fwa->ro->ro_rt->rt_refcnt++;
2461 if (fwa->dst == (struct sockaddr_in *)&fwa->ro->ro_dst) {
2462 /* 'dst' points into 'ro' */
2463 fwa->dst = (struct sockaddr_in *)&(pkt->ro.ro_dst);
2464 }
2465 pkt->dn_dst = fwa->dst;
2466 pkt->flags = fwa->flags;
2467 }
2468
2469 m->m_pkthdr.fw_flags |= DUMMYNET_MBUF_TAGGED;
2470 ip_dn_queue(m);
2471 }
2472
2473 /*
2474 * When a rule is added/deleted, clear the next_rule pointers in all rules.
2475 * These will be reconstructed on the fly as packets are matched.
2476 * Must be called at splimp().
2477 */
2478 static void
2479 ipfw_flush_rule_ptrs(struct ipfw_context *ctx)
2480 {
2481 struct ip_fw *rule;
2482
2483 for (rule = ctx->ipfw_layer3_chain; rule; rule = rule->next)
2484 rule->next_rule = NULL;
2485 }
2486
2487 static __inline void
2488 ipfw_inc_static_count(struct ip_fw *rule)
2489 {
2490 KKASSERT(mycpuid == 0);
2491
2492 static_count++;
2493 static_ioc_len += IOC_RULESIZE(rule);
2494 }
2495
2496 static __inline void
2497 ipfw_dec_static_count(struct ip_fw *rule)
2498 {
2499 int l = IOC_RULESIZE(rule);
2500
2501 KKASSERT(mycpuid == 0);
2502
2503 KASSERT(static_count > 0, ("invalid static count %u\n", static_count));
2504 static_count--;
2505
2506 KASSERT(static_ioc_len >= l,
2507 ("invalid static len %u\n", static_ioc_len));
2508 static_ioc_len -= l;
2509 }
2510
2511 static void
2512 ipfw_link_sibling(struct netmsg_ipfw *fwmsg, struct ip_fw *rule)
2513 {
2514 if (fwmsg->sibling != NULL) {
2515 KKASSERT(mycpuid > 0 && fwmsg->sibling->cpuid == mycpuid - 1);
2516 fwmsg->sibling->sibling = rule;
2517 }
2518 fwmsg->sibling = rule;
2519 }
2520
2521 static struct ip_fw *
2522 ipfw_create_rule(const struct ipfw_ioc_rule *ioc_rule, struct ip_fw_stub *stub)
2523 {
2524 struct ip_fw *rule;
2525
2526 rule = kmalloc(RULESIZE(ioc_rule), M_IPFW, M_WAITOK | M_ZERO);
2527
2528 rule->act_ofs = ioc_rule->act_ofs;
2529 rule->cmd_len = ioc_rule->cmd_len;
2530 rule->rulenum = ioc_rule->rulenum;
2531 rule->set = ioc_rule->set;
2532 rule->usr_flags = ioc_rule->usr_flags;
2533
2534 bcopy(ioc_rule->cmd, rule->cmd, rule->cmd_len * 4 /* XXX */);
2535
2536 rule->refcnt = 1;
2537 rule->cpuid = mycpuid;
2538
2539 rule->stub = stub;
2540 if (stub != NULL)
2541 stub->rule[mycpuid] = rule;
2542
2543 return rule;
2544 }
2545
2546 static void
2547 ipfw_add_rule_dispatch(struct netmsg *nmsg)
2548 {
2549 struct netmsg_ipfw *fwmsg = (struct netmsg_ipfw *)nmsg;
2550 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
2551 struct ip_fw *rule;
2552
2553 rule = ipfw_create_rule(fwmsg->ioc_rule, fwmsg->stub);
2554
2555 /*
2556 * Bump generation after ipfw_create_rule(),
2557 * since this function is blocking
2558 */
2559 ctx->ipfw_gen++;
2560
2561 /*
2562 * Insert rule into the pre-determined position
2563 */
2564 if (fwmsg->prev_rule != NULL) {
2565 struct ip_fw *prev, *next;
2566
2567 prev = fwmsg->prev_rule;
2568 KKASSERT(prev->cpuid == mycpuid);
2569
2570 next = fwmsg->next_rule;
2571 KKASSERT(next->cpuid == mycpuid);
2572
2573 rule->next = next;
2574 prev->next = rule;
2575
2576 /*
2577 * Move to the position on the next CPU
2578 * before the msg is forwarded.
2579 */
2580 fwmsg->prev_rule = prev->sibling;
2581 fwmsg->next_rule = next->sibling;
2582 } else {
2583 KKASSERT(fwmsg->next_rule == NULL);
2584 rule->next = ctx->ipfw_layer3_chain;
2585 ctx->ipfw_layer3_chain = rule;
2586 }
2587
2588 /* Link rule CPU sibling */
2589 ipfw_link_sibling(fwmsg, rule);
2590
2591 ipfw_flush_rule_ptrs(ctx);
2592
2593 if (mycpuid == 0) {
2594 /* Statistics only need to be updated once */
2595 ipfw_inc_static_count(rule);
2596
2597 /* Return the rule on CPU0 */
2598 nmsg->nm_lmsg.u.ms_resultp = rule;
2599 }
2600
2601 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
2602 }
2603
2604 static void
2605 ipfw_enable_state_dispatch(struct netmsg *nmsg)
2606 {
2607 struct lwkt_msg *lmsg = &nmsg->nm_lmsg;
2608 struct ip_fw *rule = lmsg->u.ms_resultp;
2609
2610 KKASSERT(rule->cpuid == mycpuid);
2611 KKASSERT(rule->stub != NULL && rule->stub->rule[mycpuid] == rule);
2612 KKASSERT(!(rule->rule_flags & IPFW_RULE_F_STATE));
2613 rule->rule_flags |= IPFW_RULE_F_STATE;
2614 lmsg->u.ms_resultp = rule->sibling;
2615
2616 ifnet_forwardmsg(lmsg, mycpuid + 1);
2617 }
2618
2619 /*
2620 * Add a new rule to the list. Copy the rule into a malloc'ed area,
2621 * then possibly create a rule number and add the rule to the list.
2622 * Update the rule_number in the input struct so the caller knows
2623 * it as well.
2624 */
2625 static void
2626 ipfw_add_rule(struct ipfw_ioc_rule *ioc_rule, uint32_t rule_flags)
2627 {
2628 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
2629 struct netmsg_ipfw fwmsg;
2630 struct netmsg *nmsg;
2631 struct ip_fw *f, *prev, *rule;
2632 struct ip_fw_stub *stub;
2633
2634 IPFW_ASSERT_CFGPORT(&curthread->td_msgport);
2635
2636 crit_enter();
2637
2638 /*
2639 * If rulenum is 0, find highest numbered rule before the
2640 * default rule, and add rule number incremental step.
2641 */
2642 if (ioc_rule->rulenum == 0) {
2643 int step = autoinc_step;
2644
2645 KKASSERT(step >= IPFW_AUTOINC_STEP_MIN &&
2646 step <= IPFW_AUTOINC_STEP_MAX);
2647
2648 /*
2649 * Locate the highest numbered rule before default
2650 */
2651 for (f = ctx->ipfw_layer3_chain; f; f = f->next) {
2652 if (f->rulenum == IPFW_DEFAULT_RULE)
2653 break;
2654 ioc_rule->rulenum = f->rulenum;
2655 }
2656 if (ioc_rule->rulenum < IPFW_DEFAULT_RULE - step)
2657 ioc_rule->rulenum += step;
2658 }
2659 KASSERT(ioc_rule->rulenum != IPFW_DEFAULT_RULE &&
2660 ioc_rule->rulenum != 0,
2661 ("invalid rule num %d\n", ioc_rule->rulenum));
2662
2663 /*
2664 * Now find the right place for the new rule in the sorted list.
2665 */
2666 for (prev = NULL, f = ctx->ipfw_layer3_chain; f;
2667 prev = f, f = f->next) {
2668 if (f->rulenum > ioc_rule->rulenum) {
2669 /* Found the location */
2670 break;
2671 }
2672 }
2673 KASSERT(f != NULL, ("no default rule?!\n"));
2674
2675 if (rule_flags & IPFW_RULE_F_STATE) {
2676 int size;
2677
2678 /*
2679 * If the new rule will create states, then allocate
2680 * a rule stub, which will be referenced by states
2681 * (dyn rules)
2682 */
2683 size = sizeof(*stub) + ((ncpus - 1) * sizeof(struct ip_fw *));
2684 stub = kmalloc(size, M_IPFW, M_WAITOK | M_ZERO);
2685 } else {
2686 stub = NULL;
2687 }
2688
2689 /*
2690 * Duplicate the rule onto each CPU.
2691 * The rule duplicated on CPU0 will be returned.
2692 */
2693 bzero(&fwmsg, sizeof(fwmsg));
2694 nmsg = &fwmsg.nmsg;
2695 netmsg_init(nmsg, &curthread->td_msgport, 0, ipfw_add_rule_dispatch);
2696 fwmsg.ioc_rule = ioc_rule;
2697 fwmsg.prev_rule = prev;
2698 fwmsg.next_rule = prev == NULL ? NULL : f;
2699 fwmsg.stub = stub;
2700
2701 ifnet_domsg(&nmsg->nm_lmsg, 0);
2702 KKASSERT(fwmsg.prev_rule == NULL && fwmsg.next_rule == NULL);
2703
2704 rule = nmsg->nm_lmsg.u.ms_resultp;
2705 KKASSERT(rule != NULL && rule->cpuid == mycpuid);
2706
2707 if (rule_flags & IPFW_RULE_F_STATE) {
2708 /*
2709 * Turn on state flag, _after_ everything on all
2710 * CPUs have been setup.
2711 */
2712 bzero(nmsg, sizeof(*nmsg));
2713 netmsg_init(nmsg, &curthread->td_msgport, 0,
2714 ipfw_enable_state_dispatch);
2715 nmsg->nm_lmsg.u.ms_resultp = rule;
2716
2717 ifnet_domsg(&nmsg->nm_lmsg, 0);
2718 KKASSERT(nmsg->nm_lmsg.u.ms_resultp == NULL);
2719 }
2720
2721 crit_exit();
2722
2723 DEB(kprintf("++ installed rule %d, static count now %d\n",
2724 rule->rulenum, static_count);)
2725 }
2726
2727 /**
2728 * Free storage associated with a static rule (including derived
2729 * dynamic rules).
2730 * The caller is in charge of clearing rule pointers to avoid
2731 * dangling pointers.
2732 * @return a pointer to the next entry.
2733 * Arguments are not checked, so they better be correct.
2734 * Must be called at splimp().
2735 */
2736 static struct ip_fw *
2737 ipfw_delete_rule(struct ipfw_context *ctx,
2738 struct ip_fw *prev, struct ip_fw *rule)
2739 {
2740 struct ip_fw *n;
2741 struct ip_fw_stub *stub;
2742
2743 ctx->ipfw_gen++;
2744
2745 /* STATE flag should have been cleared before we reach here */
2746 KKASSERT((rule->rule_flags & IPFW_RULE_F_STATE) == 0);
2747
2748 stub = rule->stub;
2749 n = rule->next;
2750 if (prev == NULL)
2751 ctx->ipfw_layer3_chain = n;
2752 else
2753 prev->next = n;
2754
2755 /* Mark the rule as invalid */
2756 rule->rule_flags |= IPFW_RULE_F_INVALID;
2757 rule->next_rule = NULL;
2758 rule->sibling = NULL;
2759 rule->stub = NULL;
2760 #ifdef foo
2761 /* Don't reset cpuid here; keep various assertion working */
2762 rule->cpuid = -1;
2763 #endif
2764
2765 /* Statistics only need to be updated once */
2766 if (mycpuid == 0)
2767 ipfw_dec_static_count(rule);
2768
2769 /* Free 'stub' on the last CPU */
2770 if (stub != NULL && mycpuid == ncpus - 1)
2771 kfree(stub, M_IPFW);
2772
2773 /* Try to free this rule */
2774 ipfw_free_rule(rule);
2775
2776 /* Return the next rule */
2777 return n;
2778 }
2779
2780 static void
2781 ipfw_flush_dispatch(struct netmsg *nmsg)
2782 {
2783 struct lwkt_msg *lmsg = &nmsg->nm_lmsg;
2784 int kill_default = lmsg->u.ms_result;
2785 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
2786 struct ip_fw *rule;
2787
2788 ipfw_flush_rule_ptrs(ctx); /* more efficient to do outside the loop */
2789
2790 while ((rule = ctx->ipfw_layer3_chain) != NULL &&
2791 (kill_default || rule->rulenum != IPFW_DEFAULT_RULE))
2792 ipfw_delete_rule(ctx, NULL, rule);
2793
2794 ifnet_forwardmsg(lmsg, mycpuid + 1);
2795 }
2796
2797 static void
2798 ipfw_disable_rule_state_dispatch(struct netmsg *nmsg)
2799 {
2800 struct netmsg_del *dmsg = (struct netmsg_del *)nmsg;
2801 struct ip_fw *rule;
2802
2803 rule = dmsg->start_rule;
2804 if (rule != NULL) {
2805 KKASSERT(rule->cpuid == mycpuid);
2806
2807 /*
2808 * Move to the position on the next CPU
2809 * before the msg is forwarded.
2810 */
2811 dmsg->start_rule = rule->sibling;
2812 } else {
2813 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
2814
2815 KKASSERT(dmsg->rulenum == 0);
2816 rule = ctx->ipfw_layer3_chain;
2817 }
2818
2819 while (rule != NULL) {
2820 if (dmsg->rulenum && rule->rulenum != dmsg->rulenum)
2821 break;
2822 rule->rule_flags &= ~IPFW_RULE_F_STATE;
2823 rule = rule->next;
2824 }
2825
2826 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
2827 }
2828
2829 /*
2830 * Deletes all rules from a chain (including the default rule
2831 * if the second argument is set).
2832 * Must be called at splimp().
2833 */
2834 static void
2835 ipfw_flush(int kill_default)
2836 {
2837 struct netmsg_del dmsg;
2838 struct netmsg nmsg;
2839 struct lwkt_msg *lmsg;
2840 struct ip_fw *rule;
2841 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
2842
2843 IPFW_ASSERT_CFGPORT(&curthread->td_msgport);
2844
2845 /*
2846 * If 'kill_default' then caller has done the necessary
2847 * msgport syncing; unnecessary to do it again.
2848 */
2849 if (!kill_default) {
2850 /*
2851 * Let ipfw_chk() know the rules are going to
2852 * be flushed, so it could jump directly to
2853 * the default rule.
2854 */
2855 ipfw_flushing = 1;
2856 netmsg_service_sync();
2857 }
2858
2859 /*
2860 * Clear STATE flag on rules, so no more states (dyn rules)
2861 * will be created.
2862 */
2863 bzero(&dmsg, sizeof(dmsg));
2864 netmsg_init(&dmsg.nmsg, &curthread->td_msgport, 0,
2865 ipfw_disable_rule_state_dispatch);
2866 ifnet_domsg(&dmsg.nmsg.nm_lmsg, 0);
2867
2868 /*
2869 * This actually nukes all states (dyn rules)
2870 */
2871 lockmgr(&dyn_lock, LK_EXCLUSIVE);
2872 for (rule = ctx->ipfw_layer3_chain; rule != NULL; rule = rule->next) {
2873 /*
2874 * Can't check IPFW_RULE_F_STATE here,
2875 * since it has been cleared previously.
2876 * Check 'stub' instead.
2877 */
2878 if (rule->stub != NULL) {
2879 /* Force removal */
2880 remove_dyn_rule_locked(rule, NULL);
2881 }
2882 }
2883 lockmgr(&dyn_lock, LK_RELEASE);
2884
2885 /*
2886 * Press the 'flush' button
2887 */
2888 bzero(&nmsg, sizeof(nmsg));
2889 netmsg_init(&nmsg, &curthread->td_msgport, 0, ipfw_flush_dispatch);
2890 lmsg = &nmsg.nm_lmsg;
2891 lmsg->u.ms_result = kill_default;
2892 ifnet_domsg(lmsg, 0);
2893
2894 KASSERT(dyn_count == 0, ("%u dyn rule remains\n", dyn_count));
2895
2896 if (kill_default) {
2897 if (ipfw_dyn_v != NULL) {
2898 /*
2899 * Free dynamic rules(state) hash table
2900 */
2901 kfree(ipfw_dyn_v, M_IPFW);
2902 ipfw_dyn_v = NULL;
2903 }
2904
2905 KASSERT(static_count == 0,
2906 ("%u static rules remains\n", static_count));
2907 KASSERT(static_ioc_len == 0,
2908 ("%u bytes of static rules remains\n", static_ioc_len));
2909 } else {
2910 KASSERT(static_count == 1,
2911 ("%u static rules remains\n", static_count));
2912 KASSERT(static_ioc_len == IOC_RULESIZE(ctx->ipfw_default_rule),
2913 ("%u bytes of static rules remains, should be %u\n",
2914 static_ioc_len, IOC_RULESIZE(ctx->ipfw_default_rule)));
2915 }
2916
2917 /* Flush is done */
2918 ipfw_flushing = 0;
2919 }
2920
2921 static void
2922 ipfw_alt_delete_rule_dispatch(struct netmsg *nmsg)
2923 {
2924 struct netmsg_del *dmsg = (struct netmsg_del *)nmsg;
2925 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
2926 struct ip_fw *rule, *prev;
2927
2928 rule = dmsg->start_rule;
2929 KKASSERT(rule->cpuid == mycpuid);
2930 dmsg->start_rule = rule->sibling;
2931
2932 prev = dmsg->prev_rule;
2933 if (prev != NULL) {
2934 KKASSERT(prev->cpuid == mycpuid);
2935
2936 /*
2937 * Move to the position on the next CPU
2938 * before the msg is forwarded.
2939 */
2940 dmsg->prev_rule = prev->sibling;
2941 }
2942
2943 /*
2944 * flush pointers outside the loop, then delete all matching
2945 * rules. 'prev' remains the same throughout the cycle.
2946 */
2947 ipfw_flush_rule_ptrs(ctx);
2948 while (rule && rule->rulenum == dmsg->rulenum)
2949 rule = ipfw_delete_rule(ctx, prev, rule);
2950
2951 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
2952 }
2953
2954 static int
2955 ipfw_alt_delete_rule(uint16_t rulenum)
2956 {
2957 struct ip_fw *prev, *rule, *f;
2958 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
2959 struct netmsg_del dmsg;
2960 struct netmsg *nmsg;
2961 int state;
2962
2963 /*
2964 * Locate first rule to delete
2965 */
2966 for (prev = NULL, rule = ctx->ipfw_layer3_chain;
2967 rule && rule->rulenum < rulenum;
2968 prev = rule, rule = rule->next)
2969 ; /* EMPTY */
2970 if (rule->rulenum != rulenum)
2971 return EINVAL;
2972
2973 /*
2974 * Check whether any rules with the given number will
2975 * create states.
2976 */
2977 state = 0;
2978 for (f = rule; f && f->rulenum == rulenum; f = f->next) {
2979 if (f->rule_flags & IPFW_RULE_F_STATE) {
2980 state = 1;
2981 break;
2982 }
2983 }
2984
2985 if (state) {
2986 /*
2987 * Clear the STATE flag, so no more states will be
2988 * created based the rules numbered 'rulenum'.
2989 */
2990 bzero(&dmsg, sizeof(dmsg));
2991 nmsg = &dmsg.nmsg;
2992 netmsg_init(nmsg, &curthread->td_msgport, 0,
2993 ipfw_disable_rule_state_dispatch);
2994 dmsg.start_rule = rule;
2995 dmsg.rulenum = rulenum;
2996
2997 ifnet_domsg(&nmsg->nm_lmsg, 0);
2998 KKASSERT(dmsg.start_rule == NULL);
2999
3000 /*
3001 * Nuke all related states
3002 */
3003 lockmgr(&dyn_lock, LK_EXCLUSIVE);
3004 for (f = rule; f && f->rulenum == rulenum; f = f->next) {
3005 /*
3006 * Can't check IPFW_RULE_F_STATE here,
3007 * since it has been cleared previously.
3008 * Check 'stub' instead.
3009 */
3010 if (f->stub != NULL) {
3011 /* Force removal */
3012 remove_dyn_rule_locked(f, NULL);
3013 }
3014 }
3015 lockmgr(&dyn_lock, LK_RELEASE);
3016 }
3017
3018 /*
3019 * Get rid of the rule duplications on all CPUs
3020 */
3021 bzero(&dmsg, sizeof(dmsg));
3022 nmsg = &dmsg.nmsg;
3023 netmsg_init(nmsg, &curthread->td_msgport, 0,
3024 ipfw_alt_delete_rule_dispatch);
3025 dmsg.prev_rule = prev;
3026 dmsg.start_rule = rule;
3027 dmsg.rulenum = rulenum;
3028
3029 ifnet_domsg(&nmsg->nm_lmsg, 0);
3030 KKASSERT(dmsg.prev_rule == NULL && dmsg.start_rule == NULL);
3031 return 0;
3032 }
3033
3034 static void
3035 ipfw_alt_delete_ruleset_dispatch(struct netmsg *nmsg)
3036 {
3037 struct netmsg_del *dmsg = (struct netmsg_del *)nmsg;
3038 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3039 struct ip_fw *prev, *rule;
3040 #ifdef INVARIANTS
3041 int del = 0;
3042 #endif
3043
3044 ipfw_flush_rule_ptrs(ctx);
3045
3046 prev = NULL;
3047 rule = ctx->ipfw_layer3_chain;
3048 while (rule != NULL) {
3049 if (rule->set == dmsg->from_set) {
3050 rule = ipfw_delete_rule(ctx, prev, rule);
3051 #ifdef INVARIANTS
3052 del = 1;
3053 #endif
3054 } else {
3055 prev = rule;
3056 rule = rule->next;
3057 }
3058 }
3059 KASSERT(del, ("no match set?!\n"));
3060
3061 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
3062 }
3063
3064 static void
3065 ipfw_disable_ruleset_state_dispatch(struct netmsg *nmsg)
3066 {
3067 struct netmsg_del *dmsg = (struct netmsg_del *)nmsg;
3068 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3069 struct ip_fw *rule;
3070 #ifdef INVARIANTS
3071 int cleared = 0;
3072 #endif
3073
3074 for (rule = ctx->ipfw_layer3_chain; rule; rule = rule->next) {
3075 if (rule->set == dmsg->from_set) {
3076 #ifdef INVARIANTS
3077 cleared = 1;
3078 #endif
3079 rule->rule_flags &= ~IPFW_RULE_F_STATE;
3080 }
3081 }
3082 KASSERT(cleared, ("no match set?!\n"));
3083
3084 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
3085 }
3086
3087 static int
3088 ipfw_alt_delete_ruleset(uint8_t set)
3089 {
3090 struct netmsg_del dmsg;
3091 struct netmsg *nmsg;
3092 int state, del;
3093 struct ip_fw *rule;
3094 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3095
3096 /*
3097 * Check whether the 'set' exists. If it exists,
3098 * then check whether any rules within the set will
3099 * try to create states.
3100 */
3101 state = 0;
3102 del = 0;
3103 for (rule = ctx->ipfw_layer3_chain; rule; rule = rule->next) {
3104 if (rule->set == set) {
3105 del = 1;
3106 if (rule->rule_flags & IPFW_RULE_F_STATE) {
3107 state = 1;
3108 break;
3109 }
3110 }
3111 }
3112 if (!del)
3113 return 0; /* XXX EINVAL? */
3114
3115 if (state) {
3116 /*
3117 * Clear the STATE flag, so no more states will be
3118 * created based the rules in this set.
3119 */
3120 bzero(&dmsg, sizeof(dmsg));
3121 nmsg = &dmsg.nmsg;
3122 netmsg_init(nmsg, &curthread->td_msgport, 0,
3123 ipfw_disable_ruleset_state_dispatch);
3124 dmsg.from_set = set;
3125
3126 ifnet_domsg(&nmsg->nm_lmsg, 0);
3127
3128 /*
3129 * Nuke all related states
3130 */
3131 lockmgr(&dyn_lock, LK_EXCLUSIVE);
3132 for (rule = ctx->ipfw_layer3_chain; rule; rule = rule->next) {
3133 if (rule->set != set)
3134 continue;
3135
3136 /*
3137 * Can't check IPFW_RULE_F_STATE here,
3138 * since it has been cleared previously.
3139 * Check 'stub' instead.
3140 */
3141 if (rule->stub != NULL) {
3142 /* Force removal */
3143 remove_dyn_rule_locked(rule, NULL);
3144 }
3145 }
3146 lockmgr(&dyn_lock, LK_RELEASE);
3147 }
3148
3149 /*
3150 * Delete this set
3151 */
3152 bzero(&dmsg, sizeof(dmsg));
3153 nmsg = &dmsg.nmsg;
3154 netmsg_init(nmsg, &curthread->td_msgport, 0,
3155 ipfw_alt_delete_ruleset_dispatch);
3156 dmsg.from_set = set;
3157
3158 ifnet_domsg(&nmsg->nm_lmsg, 0);
3159 return 0;
3160 }
3161
3162 static void
3163 ipfw_alt_move_rule_dispatch(struct netmsg *nmsg)
3164 {
3165 struct netmsg_del *dmsg = (struct netmsg_del *)nmsg;
3166 struct ip_fw *rule;
3167
3168 rule = dmsg->start_rule;
3169 KKASSERT(rule->cpuid == mycpuid);
3170
3171 /*
3172 * Move to the position on the next CPU
3173 * before the msg is forwarded.
3174 */
3175 dmsg->start_rule = rule->sibling;
3176
3177 while (rule && rule->rulenum <= dmsg->rulenum) {
3178 if (rule->rulenum == dmsg->rulenum)
3179 rule->set = dmsg->to_set;
3180 rule = rule->next;
3181 }
3182 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
3183 }
3184
3185 static int
3186 ipfw_alt_move_rule(uint16_t rulenum, uint8_t set)
3187 {
3188 struct netmsg_del dmsg;
3189 struct netmsg *nmsg;
3190 struct ip_fw *rule;
3191 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3192
3193 /*
3194 * Locate first rule to move
3195 */
3196 for (rule = ctx->ipfw_layer3_chain; rule && rule->rulenum <= rulenum;
3197 rule = rule->next) {
3198 if (rule->rulenum == rulenum && rule->set != set)
3199 break;
3200 }
3201 if (rule == NULL || rule->rulenum > rulenum)
3202 return 0; /* XXX error? */
3203
3204 bzero(&dmsg, sizeof(dmsg));
3205 nmsg = &dmsg.nmsg;
3206 netmsg_init(nmsg, &curthread->td_msgport, 0,
3207 ipfw_alt_move_rule_dispatch);
3208 dmsg.start_rule = rule;
3209 dmsg.rulenum = rulenum;
3210 dmsg.to_set = set;
3211
3212 ifnet_domsg(&nmsg->nm_lmsg, 0);
3213 KKASSERT(dmsg.start_rule == NULL);
3214 return 0;
3215 }
3216
3217 static void
3218 ipfw_alt_move_ruleset_dispatch(struct netmsg *nmsg)
3219 {
3220 struct netmsg_del *dmsg = (struct netmsg_del *)nmsg;
3221 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3222 struct ip_fw *rule;
3223
3224 for (rule = ctx->ipfw_layer3_chain; rule; rule = rule->next) {
3225 if (rule->set == dmsg->from_set)
3226 rule->set = dmsg->to_set;
3227 }
3228 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
3229 }
3230
3231 static int
3232 ipfw_alt_move_ruleset(uint8_t from_set, uint8_t to_set)
3233 {
3234 struct netmsg_del dmsg;
3235 struct netmsg *nmsg;
3236
3237 bzero(&dmsg, sizeof(dmsg));
3238 nmsg = &dmsg.nmsg;
3239 netmsg_init(nmsg, &curthread->td_msgport, 0,
3240 ipfw_alt_move_ruleset_dispatch);
3241 dmsg.from_set = from_set;
3242 dmsg.to_set = to_set;
3243
3244 ifnet_domsg(&nmsg->nm_lmsg, 0);
3245 return 0;
3246 }
3247
3248 static void
3249 ipfw_alt_swap_ruleset_dispatch(struct netmsg *nmsg)
3250 {
3251 struct netmsg_del *dmsg = (struct netmsg_del *)nmsg;
3252 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3253 struct ip_fw *rule;
3254
3255 for (rule = ctx->ipfw_layer3_chain; rule; rule = rule->next) {
3256 if (rule->set == dmsg->from_set)
3257 rule->set = dmsg->to_set;
3258 else if (rule->set == dmsg->to_set)
3259 rule->set = dmsg->from_set;
3260 }
3261 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
3262 }
3263
3264 static int
3265 ipfw_alt_swap_ruleset(uint8_t set1, uint8_t set2)
3266 {
3267 struct netmsg_del dmsg;
3268 struct netmsg *nmsg;
3269
3270 bzero(&dmsg, sizeof(dmsg));
3271 nmsg = &dmsg.nmsg;
3272 netmsg_init(nmsg, &curthread->td_msgport, 0,
3273 ipfw_alt_swap_ruleset_dispatch);
3274 dmsg.from_set = set1;
3275 dmsg.to_set = set2;
3276
3277 ifnet_domsg(&nmsg->nm_lmsg, 0);
3278 return 0;
3279 }
3280
3281 /**
3282 * Remove all rules with given number, and also do set manipulation.
3283 *
3284 * The argument is an uint32_t. The low 16 bit are the rule or set number,
3285 * the next 8 bits are the new set, the top 8 bits are the command:
3286 *
3287 * 0 delete rules with given number
3288 * 1 delete rules with given set number
3289 * 2 move rules with given number to new set
3290 * 3 move rules with given set number to new set
3291 * 4 swap sets with given numbers
3292 */
3293 static int
3294 ipfw_ctl_alter(uint32_t arg)
3295 {
3296 uint16_t rulenum;
3297 uint8_t cmd, new_set;
3298 int error = 0;
3299
3300 rulenum = arg & 0xffff;
3301 cmd = (arg >> 24) & 0xff;
3302 new_set = (arg >> 16) & 0xff;
3303
3304 if (cmd > 4)
3305 return EINVAL;
3306 if (new_set >= IPFW_DEFAULT_SET)
3307 return EINVAL;
3308 if (cmd == 0 || cmd == 2) {
3309 if (rulenum == IPFW_DEFAULT_RULE)
3310 return EINVAL;
3311 } else {
3312 if (rulenum >= IPFW_DEFAULT_SET)
3313 return EINVAL;
3314 }
3315
3316 switch (cmd) {
3317 case 0: /* delete rules with given number */
3318 error = ipfw_alt_delete_rule(rulenum);
3319 break;
3320
3321 case 1: /* delete all rules with given set number */
3322 error = ipfw_alt_delete_ruleset(rulenum);
3323 break;
3324
3325 case 2: /* move rules with given number to new set */
3326 error = ipfw_alt_move_rule(rulenum, new_set);
3327 break;
3328
3329 case 3: /* move rules with given set number to new set */
3330 error = ipfw_alt_move_ruleset(rulenum, new_set);
3331 break;
3332
3333 case 4: /* swap two sets */
3334 error = ipfw_alt_swap_ruleset(rulenum, new_set);
3335 break;
3336 }
3337 return error;
3338 }
3339
3340 /*
3341 * Clear counters for a specific rule.
3342 */
3343 static void
3344 clear_counters(struct ip_fw *rule, int log_only)
3345 {
3346 ipfw_insn_log *l = (ipfw_insn_log *)ACTION_PTR(rule);
3347
3348 if (log_only == 0) {
3349 rule->bcnt = rule->pcnt = 0;
3350 rule->timestamp = 0;
3351 }
3352 if (l->o.opcode == O_LOG)
3353 l->log_left = l->max_log;
3354 }
3355
3356 static void
3357 ipfw_zero_entry_dispatch(struct netmsg *nmsg)
3358 {
3359 struct netmsg_zent *zmsg = (struct netmsg_zent *)nmsg;
3360 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3361 struct ip_fw *rule;
3362
3363 if (zmsg->rulenum == 0) {
3364 KKASSERT(zmsg->start_rule == NULL);
3365
3366 ctx->ipfw_norule_counter = 0;
3367 for (rule = ctx->ipfw_layer3_chain; rule; rule = rule->next)
3368 clear_counters(rule, zmsg->log_only);
3369 } else {
3370 struct ip_fw *start = zmsg->start_rule;
3371
3372 KKASSERT(start->cpuid == mycpuid);
3373 KKASSERT(start->rulenum == zmsg->rulenum);
3374
3375 /*
3376 * We can have multiple rules with the same number, so we
3377 * need to clear them all.
3378 */
3379 for (rule = start; rule && rule->rulenum == zmsg->rulenum;
3380 rule = rule->next)
3381 clear_counters(rule, zmsg->log_only);
3382
3383 /*
3384 * Move to the position on the next CPU
3385 * before the msg is forwarded.
3386 */
3387 zmsg->start_rule = start->sibling;
3388 }
3389 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
3390 }
3391
3392 /**
3393 * Reset some or all counters on firewall rules.
3394 * @arg frwl is null to clear all entries, or contains a specific
3395 * rule number.
3396 * @arg log_only is 1 if we only want to reset logs, zero otherwise.
3397 */
3398 static int
3399 ipfw_ctl_zero_entry(int rulenum, int log_only)
3400 {
3401 struct netmsg_zent zmsg;
3402 struct netmsg *nmsg;
3403 const char *msg;
3404 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3405
3406 bzero(&zmsg, sizeof(zmsg));
3407 nmsg = &zmsg.nmsg;
3408 netmsg_init(nmsg, &curthread->td_msgport, 0, ipfw_zero_entry_dispatch);
3409 zmsg.log_only = log_only;
3410
3411 if (rulenum == 0) {
3412 msg = log_only ? "ipfw: All logging counts reset.\n"
3413 : "ipfw: Accounting cleared.\n";
3414 } else {
3415 struct ip_fw *rule;
3416
3417 /*
3418 * Locate the first rule with 'rulenum'
3419 */
3420 for (rule = ctx->ipfw_layer3_chain; rule; rule = rule->next) {
3421 if (rule->rulenum == rulenum)
3422 break;
3423 }
3424 if (rule == NULL) /* we did not find any matching rules */
3425 return (EINVAL);
3426 zmsg.start_rule = rule;
3427 zmsg.rulenum = rulenum;
3428
3429 msg = log_only ? "ipfw: Entry %d logging count reset.\n"
3430 : "ipfw: Entry %d cleared.\n";
3431 }
3432 ifnet_domsg(&nmsg->nm_lmsg, 0);
3433 KKASSERT(zmsg.start_rule == NULL);
3434
3435 if (fw_verbose)
3436 log(LOG_SECURITY | LOG_NOTICE, msg, rulenum);
3437 return (0);
3438 }
3439
3440 /*
3441 * Check validity of the structure before insert.
3442 * Fortunately rules are simple, so this mostly need to check rule sizes.
3443 */
3444 static int
3445 ipfw_check_ioc_rule(struct ipfw_ioc_rule *rule, int size, uint32_t *rule_flags)
3446 {
3447 int l, cmdlen = 0;
3448 int have_action = 0;
3449 ipfw_insn *cmd;
3450
3451 *rule_flags = 0;
3452
3453 /* Check for valid size */
3454 if (size < sizeof(*rule)) {
3455 kprintf("ipfw: rule too short\n");
3456 return EINVAL;
3457 }
3458 l = IOC_RULESIZE(rule);
3459 if (l != size) {
3460 kprintf("ipfw: size mismatch (have %d want %d)\n", size, l);
3461 return EINVAL;
3462 }
3463
3464 /* Check rule number */
3465 if (rule->rulenum == IPFW_DEFAULT_RULE) {
3466 kprintf("ipfw: invalid rule number\n");
3467 return EINVAL;
3468 }
3469
3470 /*
3471 * Now go for the individual checks. Very simple ones, basically only
3472 * instruction sizes.
3473 */
3474 for (l = rule->cmd_len, cmd = rule->cmd; l > 0;
3475 l -= cmdlen, cmd += cmdlen) {
3476 cmdlen = F_LEN(cmd);
3477 if (cmdlen > l) {
3478 kprintf("ipfw: opcode %d size truncated\n",
3479 cmd->opcode);
3480 return EINVAL;
3481 }
3482
3483 DEB(kprintf("ipfw: opcode %d\n", cmd->opcode);)
3484
3485 if (cmd->opcode == O_KEEP_STATE || cmd->opcode == O_LIMIT) {
3486 /* This rule will create states */
3487 *rule_flags |= IPFW_RULE_F_STATE;
3488 }
3489
3490 switch (cmd->opcode) {
3491 case O_NOP:
3492 case O_PROBE_STATE:
3493 case O_KEEP_STATE:
3494 case O_PROTO:
3495 case O_IP_SRC_ME:
3496 case O_IP_DST_ME:
3497 case O_LAYER2:
3498 case O_IN:
3499 case O_FRAG:
3500 case O_IPOPT:
3501 case O_IPLEN:
3502 case O_IPID:
3503 case O_IPTOS:
3504 case O_IPPRECEDENCE:
3505 case O_IPTTL:
3506 case O_IPVER:
3507 case O_TCPWIN:
3508 case O_TCPFLAGS:
3509 case O_TCPOPTS:
3510 case O_ESTAB:
3511 if (cmdlen != F_INSN_SIZE(ipfw_insn))
3512 goto bad_size;
3513 break;
3514
3515 case O_UID:
3516 case O_GID:
3517 case O_IP_SRC:
3518 case O_IP_DST:
3519 case O_TCPSEQ:
3520 case O_TCPACK:
3521 case O_PROB:
3522 case O_ICMPTYPE:
3523 if (cmdlen != F_INSN_SIZE(ipfw_insn_u32))
3524 goto bad_size;
3525 break;
3526
3527 case O_LIMIT:
3528 if (cmdlen != F_INSN_SIZE(ipfw_insn_limit))
3529 goto bad_size;
3530 break;
3531
3532 case O_LOG:
3533 if (cmdlen != F_INSN_SIZE(ipfw_insn_log))
3534 goto bad_size;
3535
3536 ((ipfw_insn_log *)cmd)->log_left =
3537 ((ipfw_insn_log *)cmd)->max_log;
3538
3539 break;
3540
3541 case O_IP_SRC_MASK:
3542 case O_IP_DST_MASK:
3543 if (cmdlen != F_INSN_SIZE(ipfw_insn_ip))
3544 goto bad_size;
3545 if (((ipfw_insn_ip *)cmd)->mask.s_addr == 0) {
3546 kprintf("ipfw: opcode %d, useless rule\n",
3547 cmd->opcode);
3548 return EINVAL;
3549 }
3550 break;
3551
3552 case O_IP_SRC_SET:
3553 case O_IP_DST_SET:
3554 if (cmd->arg1 == 0 || cmd->arg1 > 256) {
3555 kprintf("ipfw: invalid set size %d\n",
3556 cmd->arg1);
3557 return EINVAL;
3558 }
3559 if (cmdlen != F_INSN_SIZE(ipfw_insn_u32) +
3560 (cmd->arg1+31)/32 )
3561 goto bad_size;
3562 break;
3563
3564 case O_MACADDR2:
3565 if (cmdlen != F_INSN_SIZE(ipfw_insn_mac))
3566 goto bad_size;
3567 break;
3568
3569 case O_MAC_TYPE:
3570 case O_IP_SRCPORT:
3571 case O_IP_DSTPORT: /* XXX artificial limit, 30 port pairs */
3572 if (cmdlen < 2 || cmdlen > 31)
3573 goto bad_size;
3574 break;
3575
3576 case O_RECV:
3577 case O_XMIT:
3578 case O_VIA:
3579 if (cmdlen != F_INSN_SIZE(ipfw_insn_if))
3580 goto bad_size;
3581 break;
3582
3583 case O_PIPE:
3584 case O_QUEUE:
3585 if (cmdlen != F_INSN_SIZE(ipfw_insn_pipe))
3586 goto bad_size;
3587 goto check_action;
3588
3589 case O_FORWARD_IP:
3590 if (cmdlen != F_INSN_SIZE(ipfw_insn_sa))
3591 goto bad_size;
3592 goto check_action;
3593
3594 case O_FORWARD_MAC: /* XXX not implemented yet */
3595 case O_CHECK_STATE:
3596 case O_COUNT:
3597 case O_ACCEPT:
3598 case O_DENY:
3599 case O_REJECT:
3600 case O_SKIPTO:
3601 case O_DIVERT:
3602 case O_TEE:
3603 if (cmdlen != F_INSN_SIZE(ipfw_insn))
3604 goto bad_size;
3605 check_action:
3606 if (have_action) {
3607 kprintf("ipfw: opcode %d, multiple actions"
3608 " not allowed\n",
3609 cmd->opcode);
3610 return EINVAL;
3611 }
3612 have_action = 1;
3613 if (l != cmdlen) {
3614 kprintf("ipfw: opcode %d, action must be"
3615 " last opcode\n",
3616 cmd->opcode);
3617 return EINVAL;
3618 }
3619 break;
3620 default:
3621 kprintf("ipfw: opcode %d, unknown opcode\n",
3622 cmd->opcode);
3623 return EINVAL;
3624 }
3625 }
3626 if (have_action == 0) {
3627 kprintf("ipfw: missing action\n");
3628 return EINVAL;
3629 }
3630 return 0;
3631
3632 bad_size:
3633 kprintf("ipfw: opcode %d size %d wrong\n",
3634 cmd->opcode, cmdlen);
3635 return EINVAL;
3636 }
3637
3638 static int
3639 ipfw_ctl_add_rule(struct sockopt *sopt)
3640 {
3641 struct ipfw_ioc_rule *ioc_rule;
3642 size_t size;
3643 uint32_t rule_flags;
3644 int error;
3645
3646 size = sopt->sopt_valsize;
3647 if (size > (sizeof(uint32_t) * IPFW_RULE_SIZE_MAX) ||
3648 size < sizeof(*ioc_rule)) {
3649 return EINVAL;
3650 }
3651 if (size != (sizeof(uint32_t) * IPFW_RULE_SIZE_MAX)) {
3652 sopt->sopt_val = krealloc(sopt->sopt_val, sizeof(uint32_t) *
3653 IPFW_RULE_SIZE_MAX, M_TEMP, M_WAITOK);
3654 }
3655 ioc_rule = sopt->sopt_val;
3656
3657 error = ipfw_check_ioc_rule(ioc_rule, size, &rule_flags);
3658 if (error)
3659 return error;
3660
3661 ipfw_add_rule(ioc_rule, rule_flags);
3662
3663 if (sopt->sopt_dir == SOPT_GET)
3664 sopt->sopt_valsize = IOC_RULESIZE(ioc_rule);
3665 return 0;
3666 }
3667
3668 static void *
3669 ipfw_copy_rule(const struct ip_fw *rule, struct ipfw_ioc_rule *ioc_rule)
3670 {
3671 const struct ip_fw *sibling;
3672 #ifdef INVARIANTS
3673 int i;
3674 #endif
3675
3676 KKASSERT(rule->cpuid == 0);
3677
3678 ioc_rule->act_ofs = rule->act_ofs;
3679 ioc_rule->cmd_len = rule->cmd_len;
3680 ioc_rule->rulenum = rule->rulenum;
3681 ioc_rule->set = rule->set;
3682 ioc_rule->usr_flags = rule->usr_flags;
3683
3684 ioc_rule->set_disable = ipfw_ctx[mycpuid]->ipfw_set_disable;
3685 ioc_rule->static_count = static_count;
3686 ioc_rule->static_len = static_ioc_len;
3687
3688 /*
3689 * Visit (read-only) all of the rule's duplications to get
3690 * the necessary statistics
3691 */
3692 #ifdef INVARIANTS
3693 i = 0;
3694 #endif
3695 ioc_rule->pcnt = 0;
3696 ioc_rule->bcnt = 0;
3697 ioc_rule->timestamp = 0;
3698 for (sibling = rule; sibling != NULL; sibling = sibling->sibling) {
3699 ioc_rule->pcnt += sibling->pcnt;
3700 ioc_rule->bcnt += sibling->bcnt;
3701 if (sibling->timestamp > ioc_rule->timestamp)
3702 ioc_rule->timestamp = sibling->timestamp;
3703 #ifdef INVARIANTS
3704 ++i;
3705 #endif
3706 }
3707 KASSERT(i == ncpus, ("static rule is not duplicated on every cpu\n"));
3708
3709 bcopy(rule->cmd, ioc_rule->cmd, ioc_rule->cmd_len * 4 /* XXX */);
3710
3711 return ((uint8_t *)ioc_rule + IOC_RULESIZE(ioc_rule));
3712 }
3713
3714 static void
3715 ipfw_copy_state(const ipfw_dyn_rule *dyn_rule,
3716 struct ipfw_ioc_state *ioc_state)
3717 {
3718 const struct ipfw_flow_id *id;
3719 struct ipfw_ioc_flowid *ioc_id;
3720
3721 ioc_state->expire = TIME_LEQ(dyn_rule->expire, time_second) ?
3722 0 : dyn_rule->expire - time_second;
3723 ioc_state->pcnt = dyn_rule->pcnt;
3724 ioc_state->bcnt = dyn_rule->bcnt;
3725
3726 ioc_state->dyn_type = dyn_rule->dyn_type;
3727 ioc_state->count = dyn_rule->count;
3728
3729 ioc_state->rulenum = dyn_rule->stub->rule[mycpuid]->rulenum;
3730
3731 id = &dyn_rule->id;
3732 ioc_id = &ioc_state->id;
3733
3734 ioc_id->type = ETHERTYPE_IP;
3735 ioc_id->u.ip.dst_ip = id->dst_ip;
3736 ioc_id->u.ip.src_ip = id->src_ip;
3737 ioc_id->u.ip.dst_port = id->dst_port;
3738 ioc_id->u.ip.src_port = id->src_port;
3739 ioc_id->u.ip.proto = id->proto;
3740 }
3741
3742 static int
3743 ipfw_ctl_get_rules(struct sockopt *sopt)
3744 {
3745 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3746 struct ip_fw *rule;
3747 void *bp;
3748 size_t size;
3749 uint32_t dcount = 0;
3750
3751 /*
3752 * pass up a copy of the current rules. Static rules
3753 * come first (the last of which has number IPFW_DEFAULT_RULE),
3754 * followed by a possibly empty list of dynamic rule.
3755 */
3756 crit_enter();
3757
3758 size = static_ioc_len; /* size of static rules */
3759 if (ipfw_dyn_v) { /* add size of dyn.rules */
3760 dcount = dyn_count;
3761 size += dcount * sizeof(struct ipfw_ioc_state);
3762 }
3763
3764 if (sopt->sopt_valsize < size) {
3765 /* short length, no need to return incomplete rules */
3766 /* XXX: if superuser, no need to zero buffer */
3767 bzero(sopt->sopt_val, sopt->sopt_valsize);
3768 return 0;
3769 }
3770 bp = sopt->sopt_val;
3771
3772 for (rule = ctx->ipfw_layer3_chain; rule; rule = rule->next)
3773 bp = ipfw_copy_rule(rule, bp);
3774
3775 if (ipfw_dyn_v && dcount != 0) {
3776 struct ipfw_ioc_state *ioc_state = bp;
3777 uint32_t dcount2 = 0;
3778 #ifdef INVARIANTS
3779 size_t old_size = size;
3780 #endif
3781 int i;
3782
3783 lockmgr(&dyn_lock, LK_SHARED);
3784
3785 /* Check 'ipfw_dyn_v' again with lock held */
3786 if (ipfw_dyn_v == NULL)
3787 goto skip;
3788
3789 for (i = 0; i < curr_dyn_buckets; i++) {
3790 ipfw_dyn_rule *p;
3791
3792 /*
3793 * The # of dynamic rules may have grown after the
3794 * snapshot of 'dyn_count' was taken, so we will have
3795 * to check 'dcount' (snapshot of dyn_count) here to
3796 * make sure that we don't overflow the pre-allocated
3797 * buffer.
3798 */
3799 for (p = ipfw_dyn_v[i]; p != NULL && dcount != 0;
3800 p = p->next, ioc_state++, dcount--, dcount2++)
3801 ipfw_copy_state(p, ioc_state);
3802 }
3803 skip:
3804 lockmgr(&dyn_lock, LK_RELEASE);
3805
3806 /*
3807 * The # of dynamic rules may be shrinked after the
3808 * snapshot of 'dyn_count' was taken. To give user a
3809 * correct dynamic rule count, we use the 'dcount2'
3810 * calculated above (with shared lockmgr lock held).
3811 */
3812 size = static_ioc_len +
3813 (dcount2 * sizeof(struct ipfw_ioc_state));
3814 KKASSERT(size <= old_size);
3815 }
3816
3817 crit_exit();
3818
3819 sopt->sopt_valsize = size;
3820 return 0;
3821 }
3822
3823 static void
3824 ipfw_set_disable_dispatch(struct netmsg *nmsg)
3825 {
3826 struct lwkt_msg *lmsg = &nmsg->nm_lmsg;
3827 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3828
3829 ctx->ipfw_gen++;
3830 ctx->ipfw_set_disable = lmsg->u.ms_result32;
3831
3832 ifnet_forwardmsg(lmsg, mycpuid + 1);
3833 }
3834
3835 static void
3836 ipfw_ctl_set_disable(uint32_t disable, uint32_t enable)
3837 {
3838 struct netmsg nmsg;
3839 struct lwkt_msg *lmsg;
3840 uint32_t set_disable;
3841
3842 /* IPFW_DEFAULT_SET is always enabled */
3843 enable |= (1 << IPFW_DEFAULT_SET);
3844 set_disable = (ipfw_ctx[mycpuid]->ipfw_set_disable | disable) & ~enable;
3845
3846 bzero(&nmsg, sizeof(nmsg));
3847 netmsg_init(&nmsg, &curthread->td_msgport, 0, ipfw_set_disable_dispatch);
3848 lmsg = &nmsg.nm_lmsg;
3849 lmsg->u.ms_result32 = set_disable;
3850
3851 ifnet_domsg(lmsg, 0);
3852 }
3853
3854 /**
3855 * {set|get}sockopt parser.
3856 */
3857 static int
3858 ipfw_ctl(struct sockopt *sopt)
3859 {
3860 int error, rulenum;
3861 uint32_t *masks;
3862 size_t size;
3863
3864 error = 0;
3865
3866 switch (sopt->sopt_name) {
3867 case IP_FW_GET:
3868 error = ipfw_ctl_get_rules(sopt);
3869 break;
3870
3871 case IP_FW_FLUSH:
3872 /*
3873 * Normally we cannot release the lock on each iteration.
3874 * We could do it here only because we start from the head all
3875 * the times so there is no risk of missing some entries.
3876 * On the other hand, the risk is that we end up with
3877 * a very inconsistent ruleset, so better keep the lock
3878 * around the whole cycle.
3879 *
3880 * XXX this code can be improved by resetting the head of
3881 * the list to point to the default rule, and then freeing
3882 * the old list without the need for a lock.
3883 */
3884
3885 crit_enter();
3886 ipfw_flush(0 /* keep default rule */);
3887 crit_exit();
3888 break;
3889
3890 case IP_FW_ADD:
3891 error = ipfw_ctl_add_rule(sopt);
3892 break;
3893
3894 case IP_FW_DEL:
3895 /*
3896 * IP_FW_DEL is used for deleting single rules or sets,
3897 * and (ab)used to atomically manipulate sets.
3898 * Argument size is used to distinguish between the two:
3899 * sizeof(uint32_t)
3900 * delete single rule or set of rules,
3901 * or reassign rules (or sets) to a different set.
3902 * 2 * sizeof(uint32_t)
3903 * atomic disable/enable sets.
3904 * first uint32_t contains sets to be disabled,
3905 * second uint32_t contains sets to be enabled.
3906 */
3907 masks = sopt->sopt_val;
3908 size = sopt->sopt_valsize;
3909 if (size == sizeof(*masks)) {
3910 /*
3911 * Delete or reassign static rule
3912 */
3913 error = ipfw_ctl_alter(masks[0]);
3914 } else if (size == (2 * sizeof(*masks))) {
3915 /*
3916 * Set enable/disable
3917 */
3918 ipfw_ctl_set_disable(masks[0], masks[1]);
3919 } else {
3920 error = EINVAL;
3921 }
3922 break;
3923
3924 case IP_FW_ZERO:
3925 case IP_FW_RESETLOG: /* argument is an int, the rule number */
3926 rulenum = 0;
3927
3928 if (sopt->sopt_val != 0) {
3929 error = soopt_to_kbuf(sopt, &rulenum,
3930 sizeof(int), sizeof(int));
3931 if (error)
3932 break;
3933 }
3934 error = ipfw_ctl_zero_entry(rulenum,
3935 sopt->sopt_name == IP_FW_RESETLOG);
3936 break;
3937
3938 default:
3939 kprintf("ipfw_ctl invalid option %d\n", sopt->sopt_name);
3940 error = EINVAL;
3941 }
3942 return error;
3943 }
3944
3945 /*
3946 * This procedure is only used to handle keepalives. It is invoked
3947 * every dyn_keepalive_period
3948 */
3949 static void
3950 ipfw_tick(void *dummy __unused)
3951 {
3952 time_t keep_alive;
3953 uint32_t gen;
3954 int i;
3955
3956 if (ipfw_dyn_v == NULL || dyn_count == 0)
3957 goto done;
3958
3959 keep_alive = time_second;
3960
3961 lockmgr(&dyn_lock, LK_EXCLUSIVE);
3962 again:
3963 if (ipfw_dyn_v == NULL || dyn_count == 0) {
3964 lockmgr(&dyn_lock, LK_RELEASE);
3965 goto done;
3966 }
3967 gen = dyn_buckets_gen;
3968
3969 for (i = 0; i < curr_dyn_buckets; i++) {
3970 ipfw_dyn_rule *q, *prev;
3971
3972 for (prev = NULL, q = ipfw_dyn_v[i]; q != NULL;) {
3973 uint32_t ack_rev, ack_fwd;
3974 struct ipfw_flow_id id;
3975
3976 if (q->dyn_type == O_LIMIT_PARENT)
3977 goto next;
3978
3979 if (TIME_LEQ(q->expire, time_second)) {
3980 /* State expired */
3981 UNLINK_DYN_RULE(prev, ipfw_dyn_v[i], q);
3982 continue;
3983 }
3984
3985 /*
3986 * Keep alive processing
3987 */
3988
3989 if (!dyn_keepalive)
3990 goto next;
3991 if (q->id.proto != IPPROTO_TCP)
3992 goto next;
3993 if ((q->state & BOTH_SYN) != BOTH_SYN)
3994 goto next;
3995 if (TIME_LEQ(time_second + dyn_keepalive_interval,
3996 q->expire))
3997 goto next; /* too early */
3998 if (q->keep_alive == keep_alive)
3999 goto next; /* alreay done */
4000
4001 /*
4002 * Save necessary information, so that they could
4003 * survive after possible blocking in send_pkt()
4004 */
4005 id = q->id;
4006 ack_rev = q->ack_rev;
4007 ack_fwd = q->ack_fwd;
4008
4009 /* Sending has been started */
4010 q->keep_alive = keep_alive;
4011
4012 /* Release lock to avoid possible dead lock */
4013 lockmgr(&dyn_lock, LK_RELEASE);
4014 send_pkt(&id, ack_rev - 1, ack_fwd, TH_SYN);
4015 send_pkt(&id, ack_fwd - 1, ack_rev, 0);
4016 lockmgr(&dyn_lock, LK_EXCLUSIVE);
4017
4018 if (gen != dyn_buckets_gen) {
4019 /*
4020 * Dyn bucket array has been changed during
4021 * the above two sending; reiterate.
4022 */
4023 goto again;
4024 }
4025 next:
4026 prev = q;
4027 q = q->next;
4028 }
4029 }
4030 lockmgr(&dyn_lock, LK_RELEASE);
4031 done:
4032 callout_reset(&ipfw_timeout_h, dyn_keepalive_period * hz,
4033 ipfw_tick, NULL);
4034 }
4035
4036 static int
4037 ipfw_sysctl_autoinc_step(SYSCTL_HANDLER_ARGS)
4038 {
4039 return sysctl_int_range(oidp, arg1, arg2, req,
4040 IPFW_AUTOINC_STEP_MIN, IPFW_AUTOINC_STEP_MAX);
4041 }
4042
4043 static int
4044 ipfw_sysctl_dyn_buckets(SYSCTL_HANDLER_ARGS)
4045 {
4046 int error, value;
4047
4048 lockmgr(&dyn_lock, LK_EXCLUSIVE);
4049
4050 value = dyn_buckets;
4051 error = sysctl_handle_int(oidp, &value, 0, req);
4052 if (error || !req->newptr)
4053 goto back;
4054
4055 /*
4056 * Make sure we have a power of 2 and
4057 * do not allow more than 64k entries.
4058 */
4059 error = EINVAL;
4060 if (value <= 1 || value > 65536)
4061 goto back;
4062 if ((value & (value - 1)) != 0)
4063 goto back;
4064
4065 error = 0;
4066 dyn_buckets = value;
4067 back:
4068 lockmgr(&dyn_lock, LK_RELEASE);
4069 return error;
4070 }
4071
4072 static int
4073 ipfw_sysctl_dyn_fin(SYSCTL_HANDLER_ARGS)
4074 {
4075 return sysctl_int_range(oidp, arg1, arg2, req,
4076 1, dyn_keepalive_period - 1);
4077 }
4078
4079 static int
4080 ipfw_sysctl_dyn_rst(SYSCTL_HANDLER_ARGS)
4081 {
4082 return sysctl_int_range(oidp, arg1, arg2, req,
4083 1, dyn_keepalive_period - 1);
4084 }
4085
4086 static void
4087 ipfw_ctx_init_dispatch(struct netmsg *nmsg)
4088 {
4089 struct netmsg_ipfw *fwmsg = (struct netmsg_ipfw *)nmsg;
4090 struct ipfw_context *ctx;
4091 struct ip_fw *def_rule;
4092
4093 ctx = kmalloc(sizeof(*ctx), M_IPFW, M_WAITOK | M_ZERO);
4094 ipfw_ctx[mycpuid] = ctx;
4095
4096 def_rule = kmalloc(sizeof(*def_rule), M_IPFW, M_WAITOK | M_ZERO);
4097
4098 def_rule->act_ofs = 0;
4099 def_rule->rulenum = IPFW_DEFAULT_RULE;
4100 def_rule->cmd_len = 1;
4101 def_rule->set = IPFW_DEFAULT_SET;
4102
4103 def_rule->cmd[0].len = 1;
4104 #ifdef IPFIREWALL_DEFAULT_TO_ACCEPT
4105 def_rule->cmd[0].opcode = O_ACCEPT;
4106 #else
4107 def_rule->cmd[0].opcode = O_DENY;
4108 #endif
4109
4110 def_rule->refcnt = 1;
4111 def_rule->cpuid = mycpuid;
4112
4113 /* Install the default rule */
4114 ctx->ipfw_default_rule = def_rule;
4115 ctx->ipfw_layer3_chain = def_rule;
4116
4117 /* Link rule CPU sibling */
4118 ipfw_link_sibling(fwmsg, def_rule);
4119
4120 /* Statistics only need to be updated once */
4121 if (mycpuid == 0)
4122 ipfw_inc_static_count(def_rule);
4123
4124 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
4125 }
4126
4127 static void
4128 ipfw_init_dispatch(struct netmsg *nmsg)
4129 {
4130 struct netmsg_ipfw fwmsg;
4131 int error = 0;
4132
4133 crit_enter();
4134
4135 if (IPFW_LOADED) {
4136 kprintf("IP firewall already loaded\n");
4137 error = EEXIST;
4138 goto reply;
4139 }
4140
4141 bzero(&fwmsg, sizeof(fwmsg));
4142 netmsg_init(&fwmsg.nmsg, &curthread->td_msgport, 0,
4143 ipfw_ctx_init_dispatch);
4144 ifnet_domsg(&fwmsg.nmsg.nm_lmsg, 0);
4145
4146 ip_fw_chk_ptr = ipfw_chk;
4147 ip_fw_ctl_ptr = ipfw_ctl;
4148 ip_fw_dn_io_ptr = ipfw_dummynet_io;
4149
4150 kprintf("ipfw2 initialized, divert %s, "
4151 "rule-based forwarding enabled, default to %s, logging ",
4152 #ifdef IPDIVERT
4153 "enabled",
4154 #else
4155 "disabled",
4156 #endif
4157 ipfw_ctx[mycpuid]->ipfw_default_rule->cmd[0].opcode ==
4158 O_ACCEPT ? "accept" : "deny");
4159
4160 #ifdef IPFIREWALL_VERBOSE
4161 fw_verbose = 1;
4162 #endif
4163 #ifdef IPFIREWALL_VERBOSE_LIMIT
4164 verbose_limit = IPFIREWALL_VERBOSE_LIMIT;
4165 #endif
4166 if (fw_verbose == 0) {
4167 kprintf("disabled\n");
4168 } else if (verbose_limit == 0) {
4169 kprintf("unlimited\n");
4170 } else {
4171 kprintf("limited to %d packets/entry by default\n",
4172 verbose_limit);
4173 }
4174
4175 callout_init(&ipfw_timeout_h);
4176 lockinit(&dyn_lock, "ipfw_dyn", 0, 0);
4177
4178 ip_fw_loaded = 1;
4179 callout_reset(&ipfw_timeout_h, hz, ipfw_tick, NULL);
4180 reply:
4181 crit_exit();
4182 lwkt_replymsg(&nmsg->nm_lmsg, error);
4183 }
4184
4185 static int
4186 ipfw_init(void)
4187 {
4188 struct netmsg smsg;
4189
4190 netmsg_init(&smsg, &curthread->td_msgport, 0, ipfw_init_dispatch);
4191 return lwkt_domsg(IPFW_CFGPORT, &smsg.nm_lmsg, 0);
4192 }
4193
4194 #ifdef KLD_MODULE
4195
4196 static void
4197 ipfw_fini_dispatch(struct netmsg *nmsg)
4198 {
4199 int error = 0, cpu;
4200
4201 crit_enter();
4202
4203 if (ipfw_refcnt != 0) {
4204 error = EBUSY;
4205 goto reply;
4206 }
4207
4208 callout_stop(&ipfw_timeout_h);
4209
4210 ip_fw_loaded = 0;
4211 netmsg_service_sync();
4212
4213 ip_fw_chk_ptr = NULL;
4214 ip_fw_ctl_ptr = NULL;
4215 ip_fw_dn_io_ptr = NULL;
4216 ipfw_flush(1 /* kill default rule */);
4217
4218 /* Free pre-cpu context */
4219 for (cpu = 0; cpu < ncpus; ++cpu)
4220 kfree(ipfw_ctx[cpu], M_IPFW);
4221
4222 kprintf("IP firewall unloaded\n");
4223 reply:
4224 crit_exit();
4225 lwkt_replymsg(&nmsg->nm_lmsg, error);
4226 }
4227
4228 static int
4229 ipfw_fini(void)
4230 {
4231 struct netmsg smsg;
4232
4233 netmsg_init(&smsg, &curthread->td_msgport, 0, ipfw_fini_dispatch);
4234 return lwkt_domsg(IPFW_CFGPORT, &smsg.nm_lmsg, 0);
4235 }
4236
4237 #endif /* KLD_MODULE */
4238
4239 static int
4240 ipfw_modevent(module_t mod, int type, void *unused)
4241 {
4242 int err = 0;
4243
4244 switch (type) {
4245 case MOD_LOAD:
4246 err = ipfw_init();
4247 break;
4248
4249 case MOD_UNLOAD:
4250 #ifndef KLD_MODULE
4251 kprintf("ipfw statically compiled, cannot unload\n");
4252 err = EBUSY;
4253 #else
4254 err = ipfw_fini();
4255 #endif
4256 break;
4257 default:
4258 break;
4259 }
4260 return err;
4261 }
4262
4263 static moduledata_t ipfwmod = {
4264 "ipfw",
4265 ipfw_modevent,
4266 0
4267 };
4268 DECLARE_MODULE(ipfw, ipfwmod, SI_SUB_PROTO_END, SI_ORDER_ANY);
4269 MODULE_VERSION(ipfw, 1);
MP support for (parts of) the network stack