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kernel - Move mplock to machine-independent C
[dragonfly.git] / sys / net / ipfw / ip_fw2.c
blob20bf240707f3c903cb13b5adab97602320a1c507
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 1.100 2008/11/22 11:03:35 sephe Exp $
27 */
28
29 /*
30 * Implement IP packet firewall (new version)
31 */
32
33 #include "opt_ipfw.h"
34 #include "opt_inet.h"
35 #ifndef INET
36 #error IPFIREWALL requires INET.
37 #endif /* INET */
38
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/malloc.h>
42 #include <sys/mbuf.h>
43 #include <sys/kernel.h>
44 #include <sys/proc.h>
45 #include <sys/socket.h>
46 #include <sys/socketvar.h>
47 #include <sys/sysctl.h>
48 #include <sys/syslog.h>
49 #include <sys/ucred.h>
50 #include <sys/in_cksum.h>
51 #include <sys/lock.h>
52
53 #include <net/if.h>
54 #include <net/route.h>
55 #include <net/pfil.h>
56 #include <net/dummynet/ip_dummynet.h>
57
58 #include <sys/thread2.h>
59 #include <sys/mplock2.h>
60 #include <net/netmsg2.h>
61
62 #include <netinet/in.h>
63 #include <netinet/in_systm.h>
64 #include <netinet/in_var.h>
65 #include <netinet/in_pcb.h>
66 #include <netinet/ip.h>
67 #include <netinet/ip_var.h>
68 #include <netinet/ip_icmp.h>
69 #include <netinet/tcp.h>
70 #include <netinet/tcp_timer.h>
71 #include <netinet/tcp_var.h>
72 #include <netinet/tcpip.h>
73 #include <netinet/udp.h>
74 #include <netinet/udp_var.h>
75 #include <netinet/ip_divert.h>
76 #include <netinet/if_ether.h> /* XXX for ETHERTYPE_IP */
77
78 #include <net/ipfw/ip_fw2.h>
79
80 #ifdef IPFIREWALL_DEBUG
81 #define DPRINTF(fmt, ...) \
82 do { \
83 if (fw_debug > 0) \
84 kprintf(fmt, __VA_ARGS__); \
85 } while (0)
86 #else
87 #define DPRINTF(fmt, ...) ((void)0)
88 #endif
89
90 /*
91 * Description about per-CPU rule duplication:
92 *
93 * Module loading/unloading and all ioctl operations are serialized
94 * by netisr0, so we don't have any ordering or locking problems.
95 *
96 * Following graph shows how operation on per-CPU rule list is
97 * performed [2 CPU case]:
98 *
99 * CPU0 CPU1
100 *
101 * netisr0 <------------------------------------+
102 * domsg |
103 * | |
104 * | netmsg |
105 * | |
106 * V |
107 * ifnet0 |
108 * : | netmsg
109 * :(delete/add...) |
110 * : |
111 * : netmsg |
112 * forwardmsg---------->ifnet1 |
113 * : |
114 * :(delete/add...) |
115 * : |
116 * : |
117 * replymsg--------------+
118 *
119 *
120 *
121 *
122 * Rules which will not create states (dyn rules) [2 CPU case]
123 *
124 * CPU0 CPU1
125 * layer3_chain layer3_chain
126 * | |
127 * V V
128 * +-------+ sibling +-------+ sibling
129 * | rule1 |--------->| rule1 |--------->NULL
130 * +-------+ +-------+
131 * | |
132 * |next |next
133 * V V
134 * +-------+ sibling +-------+ sibling
135 * | rule2 |--------->| rule2 |--------->NULL
136 * +-------+ +-------+
137 *
138 * ip_fw.sibling:
139 * 1) Ease statistics calculation during IP_FW_GET. We only need to
140 * iterate layer3_chain on CPU0; the current rule's duplication on
141 * the other CPUs could safely be read-only accessed by using
142 * ip_fw.sibling
143 * 2) Accelerate rule insertion and deletion, e.g. rule insertion:
144 * a) In netisr0 (on CPU0) rule3 is determined to be inserted between
145 * rule1 and rule2. To make this decision we need to iterate the
146 * layer3_chain on CPU0. The netmsg, which is used to insert the
147 * rule, will contain rule1 on CPU0 as prev_rule and rule2 on CPU0
148 * as next_rule
149 * b) After the insertion on CPU0 is done, we will move on to CPU1.
150 * But instead of relocating the rule3's position on CPU1 by
151 * iterating the layer3_chain on CPU1, we set the netmsg's prev_rule
152 * to rule1->sibling and next_rule to rule2->sibling before the
153 * netmsg is forwarded to CPU1 from CPU0
154 *
155 *
156 *
157 * Rules which will create states (dyn rules) [2 CPU case]
158 * (unnecessary parts are omitted; they are same as in the previous figure)
159 *
160 * CPU0 CPU1
161 *
162 * +-------+ +-------+
163 * | rule1 | | rule1 |
164 * +-------+ +-------+
165 * ^ | | ^
166 * | |stub stub| |
167 * | | | |
168 * | +----+ +----+ |
169 * | | | |
170 * | V V |
171 * | +--------------------+ |
172 * | | rule_stub | |
173 * | | (read-only shared) | |
174 * | | | |
175 * | | back pointer array | |
176 * | | (indexed by cpuid) | |
177 * | | | |
178 * +----|---------[0] | |
179 * | [1]--------|----+
180 * | |
181 * +--------------------+
182 * ^ ^
183 * | |
184 * ........|............|............
185 * : | | :
186 * : |stub |stub :
187 * : | | :
188 * : +---------+ +---------+ :
189 * : | state1a | | state1b | .... :
190 * : +---------+ +---------+ :
191 * : :
192 * : states table :
193 * : (shared) :
194 * : (protected by dyn_lock) :
195 * ..................................
196 *
197 * [state1a and state1b are states created by rule1]
198 *
199 * ip_fw_stub:
200 * This structure is introduced so that shared (locked) state table could
201 * work with per-CPU (duplicated) static rules. It mainly bridges states
202 * and static rules and serves as static rule's place holder (a read-only
203 * shared part of duplicated rules) from states point of view.
204 *
205 * IPFW_RULE_F_STATE (only for rules which create states):
206 * o During rule installation, this flag is turned on after rule's
207 * duplications reach all CPUs, to avoid at least following race:
208 * 1) rule1 is duplicated on CPU0 and is not duplicated on CPU1 yet
209 * 2) rule1 creates state1
210 * 3) state1 is located on CPU1 by check-state
211 * But rule1 is not duplicated on CPU1 yet
212 * o During rule deletion, this flag is turned off before deleting states
213 * created by the rule and before deleting the rule itself, so no
214 * more states will be created by the to-be-deleted rule even when its
215 * duplication on certain CPUs are not eliminated yet.
216 */
217
218 #define IPFW_AUTOINC_STEP_MIN 1
219 #define IPFW_AUTOINC_STEP_MAX 1000
220 #define IPFW_AUTOINC_STEP_DEF 100
221
222 #define IPFW_DEFAULT_RULE 65535 /* rulenum for the default rule */
223 #define IPFW_DEFAULT_SET 31 /* set number for the default rule */
224
225 struct netmsg_ipfw {
226 struct netmsg nmsg;
227 const struct ipfw_ioc_rule *ioc_rule;
228 struct ip_fw *next_rule;
229 struct ip_fw *prev_rule;
230 struct ip_fw *sibling;
231 struct ip_fw_stub *stub;
232 };
233
234 struct netmsg_del {
235 struct netmsg nmsg;
236 struct ip_fw *start_rule;
237 struct ip_fw *prev_rule;
238 uint16_t rulenum;
239 uint8_t from_set;
240 uint8_t to_set;
241 };
242
243 struct netmsg_zent {
244 struct netmsg nmsg;
245 struct ip_fw *start_rule;
246 uint16_t rulenum;
247 uint16_t log_only;
248 };
249
250 struct ipfw_context {
251 struct ip_fw *ipfw_layer3_chain; /* list of rules for layer3 */
252 struct ip_fw *ipfw_default_rule; /* default rule */
253 uint64_t ipfw_norule_counter; /* counter for ipfw_log(NULL) */
254
255 /*
256 * ipfw_set_disable contains one bit per set value (0..31).
257 * If the bit is set, all rules with the corresponding set
258 * are disabled. Set IPDW_DEFAULT_SET is reserved for the
259 * default rule and CANNOT be disabled.
260 */
261 uint32_t ipfw_set_disable;
262 uint32_t ipfw_gen; /* generation of rule list */
263 };
264
265 static struct ipfw_context *ipfw_ctx[MAXCPU];
266
267 #ifdef KLD_MODULE
268 /*
269 * Module can not be unloaded, if there are references to
270 * certains rules of ipfw(4), e.g. dummynet(4)
271 */
272 static int ipfw_refcnt;
273 #endif
274
275 MALLOC_DEFINE(M_IPFW, "IpFw/IpAcct", "IpFw/IpAcct chain's");
276
277 /*
278 * Following two global variables are accessed and
279 * updated only on CPU0
280 */
281 static uint32_t static_count; /* # of static rules */
282 static uint32_t static_ioc_len; /* bytes of static rules */
283
284 /*
285 * If 1, then ipfw static rules are being flushed,
286 * ipfw_chk() will skip to the default rule.
287 */
288 static int ipfw_flushing;
289
290 static int fw_verbose;
291 static int verbose_limit;
292
293 static int fw_debug;
294 static int autoinc_step = IPFW_AUTOINC_STEP_DEF;
295
296 static int ipfw_sysctl_enable(SYSCTL_HANDLER_ARGS);
297 static int ipfw_sysctl_autoinc_step(SYSCTL_HANDLER_ARGS);
298 static int ipfw_sysctl_dyn_buckets(SYSCTL_HANDLER_ARGS);
299 static int ipfw_sysctl_dyn_fin(SYSCTL_HANDLER_ARGS);
300 static int ipfw_sysctl_dyn_rst(SYSCTL_HANDLER_ARGS);
301
302 SYSCTL_NODE(_net_inet_ip, OID_AUTO, fw, CTLFLAG_RW, 0, "Firewall");
303 SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, enable, CTLTYPE_INT | CTLFLAG_RW,
304 &fw_enable, 0, ipfw_sysctl_enable, "I", "Enable ipfw");
305 SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, autoinc_step, CTLTYPE_INT | CTLFLAG_RW,
306 &autoinc_step, 0, ipfw_sysctl_autoinc_step, "I",
307 "Rule number autincrement step");
308 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO,one_pass,CTLFLAG_RW,
309 &fw_one_pass, 0,
310 "Only do a single pass through ipfw when using dummynet(4)");
311 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, debug, CTLFLAG_RW,
312 &fw_debug, 0, "Enable printing of debug ip_fw statements");
313 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, verbose, CTLFLAG_RW,
314 &fw_verbose, 0, "Log matches to ipfw rules");
315 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, verbose_limit, CTLFLAG_RW,
316 &verbose_limit, 0, "Set upper limit of matches of ipfw rules logged");
317
318 /*
319 * Description of dynamic rules.
320 *
321 * Dynamic rules are stored in lists accessed through a hash table
322 * (ipfw_dyn_v) whose size is curr_dyn_buckets. This value can
323 * be modified through the sysctl variable dyn_buckets which is
324 * updated when the table becomes empty.
325 *
326 * XXX currently there is only one list, ipfw_dyn.
327 *
328 * When a packet is received, its address fields are first masked
329 * with the mask defined for the rule, then hashed, then matched
330 * against the entries in the corresponding list.
331 * Dynamic rules can be used for different purposes:
332 * + stateful rules;
333 * + enforcing limits on the number of sessions;
334 * + in-kernel NAT (not implemented yet)
335 *
336 * The lifetime of dynamic rules is regulated by dyn_*_lifetime,
337 * measured in seconds and depending on the flags.
338 *
339 * The total number of dynamic rules is stored in dyn_count.
340 * The max number of dynamic rules is dyn_max. When we reach
341 * the maximum number of rules we do not create anymore. This is
342 * done to avoid consuming too much memory, but also too much
343 * time when searching on each packet (ideally, we should try instead
344 * to put a limit on the length of the list on each bucket...).
345 *
346 * Each dynamic rule holds a pointer to the parent ipfw rule so
347 * we know what action to perform. Dynamic rules are removed when
348 * the parent rule is deleted. XXX we should make them survive.
349 *
350 * There are some limitations with dynamic rules -- we do not
351 * obey the 'randomized match', and we do not do multiple
352 * passes through the firewall. XXX check the latter!!!
353 *
354 * NOTE about the SHARED LOCKMGR LOCK during dynamic rule looking up:
355 * Only TCP state transition will change dynamic rule's state and ack
356 * sequences, while all packets of one TCP connection only goes through
357 * one TCP thread, so it is safe to use shared lockmgr lock during dynamic
358 * rule looking up. The keep alive callout uses exclusive lockmgr lock
359 * when it tries to find suitable dynamic rules to send keep alive, so
360 * it will not see half updated state and ack sequences. Though the expire
361 * field updating looks racy for other protocols, the resolution (second)
362 * of expire field makes this kind of race harmless.
363 * XXX statistics' updating is _not_ MPsafe!!!
364 * XXX once UDP output path is fixed, we could use lockless dynamic rule
365 * hash table
366 */
367 static ipfw_dyn_rule **ipfw_dyn_v = NULL;
368 static uint32_t dyn_buckets = 256; /* must be power of 2 */
369 static uint32_t curr_dyn_buckets = 256; /* must be power of 2 */
370 static uint32_t dyn_buckets_gen; /* generation of dyn buckets array */
371 static struct lock dyn_lock; /* dynamic rules' hash table lock */
372
373 static struct netmsg ipfw_timeout_netmsg; /* schedule ipfw timeout */
374 static struct callout ipfw_timeout_h;
375
376 /*
377 * Timeouts for various events in handing dynamic rules.
378 */
379 static uint32_t dyn_ack_lifetime = 300;
380 static uint32_t dyn_syn_lifetime = 20;
381 static uint32_t dyn_fin_lifetime = 1;
382 static uint32_t dyn_rst_lifetime = 1;
383 static uint32_t dyn_udp_lifetime = 10;
384 static uint32_t dyn_short_lifetime = 5;
385
386 /*
387 * Keepalives are sent if dyn_keepalive is set. They are sent every
388 * dyn_keepalive_period seconds, in the last dyn_keepalive_interval
389 * seconds of lifetime of a rule.
390 * dyn_rst_lifetime and dyn_fin_lifetime should be strictly lower
391 * than dyn_keepalive_period.
392 */
393
394 static uint32_t dyn_keepalive_interval = 20;
395 static uint32_t dyn_keepalive_period = 5;
396 static uint32_t dyn_keepalive = 1; /* do send keepalives */
397
398 static uint32_t dyn_count; /* # of dynamic rules */
399 static uint32_t dyn_max = 4096; /* max # of dynamic rules */
400
401 SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, dyn_buckets, CTLTYPE_INT | CTLFLAG_RW,
402 &dyn_buckets, 0, ipfw_sysctl_dyn_buckets, "I", "Number of dyn. buckets");
403 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, curr_dyn_buckets, CTLFLAG_RD,
404 &curr_dyn_buckets, 0, "Current Number of dyn. buckets");
405 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_count, CTLFLAG_RD,
406 &dyn_count, 0, "Number of dyn. rules");
407 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_max, CTLFLAG_RW,
408 &dyn_max, 0, "Max number of dyn. rules");
409 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, static_count, CTLFLAG_RD,
410 &static_count, 0, "Number of static rules");
411 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_ack_lifetime, CTLFLAG_RW,
412 &dyn_ack_lifetime, 0, "Lifetime of dyn. rules for acks");
413 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_syn_lifetime, CTLFLAG_RW,
414 &dyn_syn_lifetime, 0, "Lifetime of dyn. rules for syn");
415 SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, dyn_fin_lifetime,
416 CTLTYPE_INT | CTLFLAG_RW, &dyn_fin_lifetime, 0, ipfw_sysctl_dyn_fin, "I",
417 "Lifetime of dyn. rules for fin");
418 SYSCTL_PROC(_net_inet_ip_fw, OID_AUTO, dyn_rst_lifetime,
419 CTLTYPE_INT | CTLFLAG_RW, &dyn_rst_lifetime, 0, ipfw_sysctl_dyn_rst, "I",
420 "Lifetime of dyn. rules for rst");
421 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_udp_lifetime, CTLFLAG_RW,
422 &dyn_udp_lifetime, 0, "Lifetime of dyn. rules for UDP");
423 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_short_lifetime, CTLFLAG_RW,
424 &dyn_short_lifetime, 0, "Lifetime of dyn. rules for other situations");
425 SYSCTL_INT(_net_inet_ip_fw, OID_AUTO, dyn_keepalive, CTLFLAG_RW,
426 &dyn_keepalive, 0, "Enable keepalives for dyn. rules");
427
428 static ip_fw_chk_t ipfw_chk;
429 static void ipfw_tick(void *);
430
431 static __inline int
432 ipfw_free_rule(struct ip_fw *rule)
433 {
434 KASSERT(rule->cpuid == mycpuid, ("rule freed on cpu%d\n", mycpuid));
435 KASSERT(rule->refcnt > 0, ("invalid refcnt %u\n", rule->refcnt));
436 rule->refcnt--;
437 if (rule->refcnt == 0) {
438 kfree(rule, M_IPFW);
439 return 1;
440 }
441 return 0;
442 }
443
444 static void
445 ipfw_unref_rule(void *priv)
446 {
447 ipfw_free_rule(priv);
448 #ifdef KLD_MODULE
449 atomic_subtract_int(&ipfw_refcnt, 1);
450 #endif
451 }
452
453 static __inline void
454 ipfw_ref_rule(struct ip_fw *rule)
455 {
456 KASSERT(rule->cpuid == mycpuid, ("rule used on cpu%d\n", mycpuid));
457 #ifdef KLD_MODULE
458 atomic_add_int(&ipfw_refcnt, 1);
459 #endif
460 rule->refcnt++;
461 }
462
463 /*
464 * This macro maps an ip pointer into a layer3 header pointer of type T
465 */
466 #define L3HDR(T, ip) ((T *)((uint32_t *)(ip) + (ip)->ip_hl))
467
468 static __inline int
469 icmptype_match(struct ip *ip, ipfw_insn_u32 *cmd)
470 {
471 int type = L3HDR(struct icmp,ip)->icmp_type;
472
473 return (type <= ICMP_MAXTYPE && (cmd->d[0] & (1 << type)));
474 }
475
476 #define TT ((1 << ICMP_ECHO) | \
477 (1 << ICMP_ROUTERSOLICIT) | \
478 (1 << ICMP_TSTAMP) | \
479 (1 << ICMP_IREQ) | \
480 (1 << ICMP_MASKREQ))
481
482 static int
483 is_icmp_query(struct ip *ip)
484 {
485 int type = L3HDR(struct icmp, ip)->icmp_type;
486
487 return (type <= ICMP_MAXTYPE && (TT & (1 << type)));
488 }
489
490 #undef TT
491
492 /*
493 * The following checks use two arrays of 8 or 16 bits to store the
494 * bits that we want set or clear, respectively. They are in the
495 * low and high half of cmd->arg1 or cmd->d[0].
496 *
497 * We scan options and store the bits we find set. We succeed if
498 *
499 * (want_set & ~bits) == 0 && (want_clear & ~bits) == want_clear
500 *
501 * The code is sometimes optimized not to store additional variables.
502 */
503
504 static int
505 flags_match(ipfw_insn *cmd, uint8_t bits)
506 {
507 u_char want_clear;
508 bits = ~bits;
509
510 if (((cmd->arg1 & 0xff) & bits) != 0)
511 return 0; /* some bits we want set were clear */
512
513 want_clear = (cmd->arg1 >> 8) & 0xff;
514 if ((want_clear & bits) != want_clear)
515 return 0; /* some bits we want clear were set */
516 return 1;
517 }
518
519 static int
520 ipopts_match(struct ip *ip, ipfw_insn *cmd)
521 {
522 int optlen, bits = 0;
523 u_char *cp = (u_char *)(ip + 1);
524 int x = (ip->ip_hl << 2) - sizeof(struct ip);
525
526 for (; x > 0; x -= optlen, cp += optlen) {
527 int opt = cp[IPOPT_OPTVAL];
528
529 if (opt == IPOPT_EOL)
530 break;
531
532 if (opt == IPOPT_NOP) {
533 optlen = 1;
534 } else {
535 optlen = cp[IPOPT_OLEN];
536 if (optlen <= 0 || optlen > x)
537 return 0; /* invalid or truncated */
538 }
539
540 switch (opt) {
541 case IPOPT_LSRR:
542 bits |= IP_FW_IPOPT_LSRR;
543 break;
544
545 case IPOPT_SSRR:
546 bits |= IP_FW_IPOPT_SSRR;
547 break;
548
549 case IPOPT_RR:
550 bits |= IP_FW_IPOPT_RR;
551 break;
552
553 case IPOPT_TS:
554 bits |= IP_FW_IPOPT_TS;
555 break;
556
557 default:
558 break;
559 }
560 }
561 return (flags_match(cmd, bits));
562 }
563
564 static int
565 tcpopts_match(struct ip *ip, ipfw_insn *cmd)
566 {
567 int optlen, bits = 0;
568 struct tcphdr *tcp = L3HDR(struct tcphdr,ip);
569 u_char *cp = (u_char *)(tcp + 1);
570 int x = (tcp->th_off << 2) - sizeof(struct tcphdr);
571
572 for (; x > 0; x -= optlen, cp += optlen) {
573 int opt = cp[0];
574
575 if (opt == TCPOPT_EOL)
576 break;
577
578 if (opt == TCPOPT_NOP) {
579 optlen = 1;
580 } else {
581 optlen = cp[1];
582 if (optlen <= 0)
583 break;
584 }
585
586 switch (opt) {
587 case TCPOPT_MAXSEG:
588 bits |= IP_FW_TCPOPT_MSS;
589 break;
590
591 case TCPOPT_WINDOW:
592 bits |= IP_FW_TCPOPT_WINDOW;
593 break;
594
595 case TCPOPT_SACK_PERMITTED:
596 case TCPOPT_SACK:
597 bits |= IP_FW_TCPOPT_SACK;
598 break;
599
600 case TCPOPT_TIMESTAMP:
601 bits |= IP_FW_TCPOPT_TS;
602 break;
603
604 case TCPOPT_CC:
605 case TCPOPT_CCNEW:
606 case TCPOPT_CCECHO:
607 bits |= IP_FW_TCPOPT_CC;
608 break;
609
610 default:
611 break;
612 }
613 }
614 return (flags_match(cmd, bits));
615 }
616
617 static int
618 iface_match(struct ifnet *ifp, ipfw_insn_if *cmd)
619 {
620 if (ifp == NULL) /* no iface with this packet, match fails */
621 return 0;
622
623 /* Check by name or by IP address */
624 if (cmd->name[0] != '\0') { /* match by name */
625 /* Check name */
626 if (cmd->p.glob) {
627 if (kfnmatch(cmd->name, ifp->if_xname, 0) == 0)
628 return(1);
629 } else {
630 if (strncmp(ifp->if_xname, cmd->name, IFNAMSIZ) == 0)
631 return(1);
632 }
633 } else {
634 struct ifaddr_container *ifac;
635
636 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
637 struct ifaddr *ia = ifac->ifa;
638
639 if (ia->ifa_addr == NULL)
640 continue;
641 if (ia->ifa_addr->sa_family != AF_INET)
642 continue;
643 if (cmd->p.ip.s_addr == ((struct sockaddr_in *)
644 (ia->ifa_addr))->sin_addr.s_addr)
645 return(1); /* match */
646 }
647 }
648 return(0); /* no match, fail ... */
649 }
650
651 #define SNPARGS(buf, len) buf + len, sizeof(buf) > len ? sizeof(buf) - len : 0
652
653 /*
654 * We enter here when we have a rule with O_LOG.
655 * XXX this function alone takes about 2Kbytes of code!
656 */
657 static void
658 ipfw_log(struct ip_fw *f, u_int hlen, struct ether_header *eh,
659 struct mbuf *m, struct ifnet *oif)
660 {
661 char *action;
662 int limit_reached = 0;
663 char action2[40], proto[48], fragment[28];
664
665 fragment[0] = '\0';
666 proto[0] = '\0';
667
668 if (f == NULL) { /* bogus pkt */
669 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
670
671 if (verbose_limit != 0 &&
672 ctx->ipfw_norule_counter >= verbose_limit)
673 return;
674 ctx->ipfw_norule_counter++;
675 if (ctx->ipfw_norule_counter == verbose_limit)
676 limit_reached = verbose_limit;
677 action = "Refuse";
678 } else { /* O_LOG is the first action, find the real one */
679 ipfw_insn *cmd = ACTION_PTR(f);
680 ipfw_insn_log *l = (ipfw_insn_log *)cmd;
681
682 if (l->max_log != 0 && l->log_left == 0)
683 return;
684 l->log_left--;
685 if (l->log_left == 0)
686 limit_reached = l->max_log;
687 cmd += F_LEN(cmd); /* point to first action */
688 if (cmd->opcode == O_PROB)
689 cmd += F_LEN(cmd);
690
691 action = action2;
692 switch (cmd->opcode) {
693 case O_DENY:
694 action = "Deny";
695 break;
696
697 case O_REJECT:
698 if (cmd->arg1==ICMP_REJECT_RST) {
699 action = "Reset";
700 } else if (cmd->arg1==ICMP_UNREACH_HOST) {
701 action = "Reject";
702 } else {
703 ksnprintf(SNPARGS(action2, 0), "Unreach %d",
704 cmd->arg1);
705 }
706 break;
707
708 case O_ACCEPT:
709 action = "Accept";
710 break;
711
712 case O_COUNT:
713 action = "Count";
714 break;
715
716 case O_DIVERT:
717 ksnprintf(SNPARGS(action2, 0), "Divert %d", cmd->arg1);
718 break;
719
720 case O_TEE:
721 ksnprintf(SNPARGS(action2, 0), "Tee %d", cmd->arg1);
722 break;
723
724 case O_SKIPTO:
725 ksnprintf(SNPARGS(action2, 0), "SkipTo %d", cmd->arg1);
726 break;
727
728 case O_PIPE:
729 ksnprintf(SNPARGS(action2, 0), "Pipe %d", cmd->arg1);
730 break;
731
732 case O_QUEUE:
733 ksnprintf(SNPARGS(action2, 0), "Queue %d", cmd->arg1);
734 break;
735
736 case O_FORWARD_IP:
737 {
738 ipfw_insn_sa *sa = (ipfw_insn_sa *)cmd;
739 int len;
740
741 len = ksnprintf(SNPARGS(action2, 0),
742 "Forward to %s",
743 inet_ntoa(sa->sa.sin_addr));
744 if (sa->sa.sin_port) {
745 ksnprintf(SNPARGS(action2, len), ":%d",
746 sa->sa.sin_port);
747 }
748 }
749 break;
750
751 default:
752 action = "UNKNOWN";
753 break;
754 }
755 }
756
757 if (hlen == 0) { /* non-ip */
758 ksnprintf(SNPARGS(proto, 0), "MAC");
759 } else {
760 struct ip *ip = mtod(m, struct ip *);
761 /* these three are all aliases to the same thing */
762 struct icmp *const icmp = L3HDR(struct icmp, ip);
763 struct tcphdr *const tcp = (struct tcphdr *)icmp;
764 struct udphdr *const udp = (struct udphdr *)icmp;
765
766 int ip_off, offset, ip_len;
767 int len;
768
769 if (eh != NULL) { /* layer 2 packets are as on the wire */
770 ip_off = ntohs(ip->ip_off);
771 ip_len = ntohs(ip->ip_len);
772 } else {
773 ip_off = ip->ip_off;
774 ip_len = ip->ip_len;
775 }
776 offset = ip_off & IP_OFFMASK;
777 switch (ip->ip_p) {
778 case IPPROTO_TCP:
779 len = ksnprintf(SNPARGS(proto, 0), "TCP %s",
780 inet_ntoa(ip->ip_src));
781 if (offset == 0) {
782 ksnprintf(SNPARGS(proto, len), ":%d %s:%d",
783 ntohs(tcp->th_sport),
784 inet_ntoa(ip->ip_dst),
785 ntohs(tcp->th_dport));
786 } else {
787 ksnprintf(SNPARGS(proto, len), " %s",
788 inet_ntoa(ip->ip_dst));
789 }
790 break;
791
792 case IPPROTO_UDP:
793 len = ksnprintf(SNPARGS(proto, 0), "UDP %s",
794 inet_ntoa(ip->ip_src));
795 if (offset == 0) {
796 ksnprintf(SNPARGS(proto, len), ":%d %s:%d",
797 ntohs(udp->uh_sport),
798 inet_ntoa(ip->ip_dst),
799 ntohs(udp->uh_dport));
800 } else {
801 ksnprintf(SNPARGS(proto, len), " %s",
802 inet_ntoa(ip->ip_dst));
803 }
804 break;
805
806 case IPPROTO_ICMP:
807 if (offset == 0) {
808 len = ksnprintf(SNPARGS(proto, 0),
809 "ICMP:%u.%u ",
810 icmp->icmp_type,
811 icmp->icmp_code);
812 } else {
813 len = ksnprintf(SNPARGS(proto, 0), "ICMP ");
814 }
815 len += ksnprintf(SNPARGS(proto, len), "%s",
816 inet_ntoa(ip->ip_src));
817 ksnprintf(SNPARGS(proto, len), " %s",
818 inet_ntoa(ip->ip_dst));
819 break;
820
821 default:
822 len = ksnprintf(SNPARGS(proto, 0), "P:%d %s", ip->ip_p,
823 inet_ntoa(ip->ip_src));
824 ksnprintf(SNPARGS(proto, len), " %s",
825 inet_ntoa(ip->ip_dst));
826 break;
827 }
828
829 if (ip_off & (IP_MF | IP_OFFMASK)) {
830 ksnprintf(SNPARGS(fragment, 0), " (frag %d:%d@%d%s)",
831 ntohs(ip->ip_id), ip_len - (ip->ip_hl << 2),
832 offset << 3, (ip_off & IP_MF) ? "+" : "");
833 }
834 }
835
836 if (oif || m->m_pkthdr.rcvif) {
837 log(LOG_SECURITY | LOG_INFO,
838 "ipfw: %d %s %s %s via %s%s\n",
839 f ? f->rulenum : -1,
840 action, proto, oif ? "out" : "in",
841 oif ? oif->if_xname : m->m_pkthdr.rcvif->if_xname,
842 fragment);
843 } else {
844 log(LOG_SECURITY | LOG_INFO,
845 "ipfw: %d %s %s [no if info]%s\n",
846 f ? f->rulenum : -1,
847 action, proto, fragment);
848 }
849
850 if (limit_reached) {
851 log(LOG_SECURITY | LOG_NOTICE,
852 "ipfw: limit %d reached on entry %d\n",
853 limit_reached, f ? f->rulenum : -1);
854 }
855 }
856
857 #undef SNPARGS
858
859 /*
860 * IMPORTANT: the hash function for dynamic rules must be commutative
861 * in source and destination (ip,port), because rules are bidirectional
862 * and we want to find both in the same bucket.
863 */
864 static __inline int
865 hash_packet(struct ipfw_flow_id *id)
866 {
867 uint32_t i;
868
869 i = (id->dst_ip) ^ (id->src_ip) ^ (id->dst_port) ^ (id->src_port);
870 i &= (curr_dyn_buckets - 1);
871 return i;
872 }
873
874 /**
875 * unlink a dynamic rule from a chain. prev is a pointer to
876 * the previous one, q is a pointer to the rule to delete,
877 * head is a pointer to the head of the queue.
878 * Modifies q and potentially also head.
879 */
880 #define UNLINK_DYN_RULE(prev, head, q) \
881 do { \
882 ipfw_dyn_rule *old_q = q; \
883 \
884 /* remove a refcount to the parent */ \
885 if (q->dyn_type == O_LIMIT) \
886 q->parent->count--; \
887 DPRINTF("-- unlink entry 0x%08x %d -> 0x%08x %d, %d left\n", \
888 q->id.src_ip, q->id.src_port, \
889 q->id.dst_ip, q->id.dst_port, dyn_count - 1); \
890 if (prev != NULL) \
891 prev->next = q = q->next; \
892 else \
893 head = q = q->next; \
894 KASSERT(dyn_count > 0, ("invalid dyn count %u\n", dyn_count)); \
895 dyn_count--; \
896 kfree(old_q, M_IPFW); \
897 } while (0)
898
899 #define TIME_LEQ(a, b) ((int)((a) - (b)) <= 0)
900
901 /**
902 * Remove dynamic rules pointing to "rule", or all of them if rule == NULL.
903 *
904 * If keep_me == NULL, rules are deleted even if not expired,
905 * otherwise only expired rules are removed.
906 *
907 * The value of the second parameter is also used to point to identify
908 * a rule we absolutely do not want to remove (e.g. because we are
909 * holding a reference to it -- this is the case with O_LIMIT_PARENT
910 * rules). The pointer is only used for comparison, so any non-null
911 * value will do.
912 */
913 static void
914 remove_dyn_rule_locked(struct ip_fw *rule, ipfw_dyn_rule *keep_me)
915 {
916 static uint32_t last_remove = 0; /* XXX */
917
918 #define FORCE (keep_me == NULL)
919
920 ipfw_dyn_rule *prev, *q;
921 int i, pass = 0, max_pass = 0, unlinked = 0;
922
923 if (ipfw_dyn_v == NULL || dyn_count == 0)
924 return;
925 /* do not expire more than once per second, it is useless */
926 if (!FORCE && last_remove == time_second)
927 return;
928 last_remove = time_second;
929
930 /*
931 * because O_LIMIT refer to parent rules, during the first pass only
932 * remove child and mark any pending LIMIT_PARENT, and remove
933 * them in a second pass.
934 */
935 next_pass:
936 for (i = 0; i < curr_dyn_buckets; i++) {
937 for (prev = NULL, q = ipfw_dyn_v[i]; q;) {
938 /*
939 * Logic can become complex here, so we split tests.
940 */
941 if (q == keep_me)
942 goto next;
943 if (rule != NULL && rule->stub != q->stub)
944 goto next; /* not the one we are looking for */
945 if (q->dyn_type == O_LIMIT_PARENT) {
946 /*
947 * handle parent in the second pass,
948 * record we need one.
949 */
950 max_pass = 1;
951 if (pass == 0)
952 goto next;
953 if (FORCE && q->count != 0) {
954 /* XXX should not happen! */
955 kprintf("OUCH! cannot remove rule, "
956 "count %d\n", q->count);
957 }
958 } else {
959 if (!FORCE && !TIME_LEQ(q->expire, time_second))
960 goto next;
961 }
962 unlinked = 1;
963 UNLINK_DYN_RULE(prev, ipfw_dyn_v[i], q);
964 continue;
965 next:
966 prev = q;
967 q = q->next;
968 }
969 }
970 if (pass++ < max_pass)
971 goto next_pass;
972
973 if (unlinked)
974 ++dyn_buckets_gen;
975
976 #undef FORCE
977 }
978
979 /**
980 * lookup a dynamic rule.
981 */
982 static ipfw_dyn_rule *
983 lookup_dyn_rule(struct ipfw_flow_id *pkt, int *match_direction,
984 struct tcphdr *tcp)
985 {
986 /*
987 * stateful ipfw extensions.
988 * Lookup into dynamic session queue
989 */
990 #define MATCH_REVERSE 0
991 #define MATCH_FORWARD 1
992 #define MATCH_NONE 2
993 #define MATCH_UNKNOWN 3
994 int i, dir = MATCH_NONE;
995 ipfw_dyn_rule *prev, *q=NULL;
996
997 if (ipfw_dyn_v == NULL)
998 goto done; /* not found */
999
1000 i = hash_packet(pkt);
1001 for (prev = NULL, q = ipfw_dyn_v[i]; q != NULL;) {
1002 if (q->dyn_type == O_LIMIT_PARENT)
1003 goto next;
1004
1005 if (TIME_LEQ(q->expire, time_second)) {
1006 /*
1007 * Entry expired; skip.
1008 * Let ipfw_tick() take care of it
1009 */
1010 goto next;
1011 }
1012
1013 if (pkt->proto == q->id.proto) {
1014 if (pkt->src_ip == q->id.src_ip &&
1015 pkt->dst_ip == q->id.dst_ip &&
1016 pkt->src_port == q->id.src_port &&
1017 pkt->dst_port == q->id.dst_port) {
1018 dir = MATCH_FORWARD;
1019 break;
1020 }
1021 if (pkt->src_ip == q->id.dst_ip &&
1022 pkt->dst_ip == q->id.src_ip &&
1023 pkt->src_port == q->id.dst_port &&
1024 pkt->dst_port == q->id.src_port) {
1025 dir = MATCH_REVERSE;
1026 break;
1027 }
1028 }
1029 next:
1030 prev = q;
1031 q = q->next;
1032 }
1033 if (q == NULL)
1034 goto done; /* q = NULL, not found */
1035
1036 if (pkt->proto == IPPROTO_TCP) { /* update state according to flags */
1037 u_char flags = pkt->flags & (TH_FIN|TH_SYN|TH_RST);
1038
1039 #define BOTH_SYN (TH_SYN | (TH_SYN << 8))
1040 #define BOTH_FIN (TH_FIN | (TH_FIN << 8))
1041
1042 q->state |= (dir == MATCH_FORWARD ) ? flags : (flags << 8);
1043 switch (q->state) {
1044 case TH_SYN: /* opening */
1045 q->expire = time_second + dyn_syn_lifetime;
1046 break;
1047
1048 case BOTH_SYN: /* move to established */
1049 case BOTH_SYN | TH_FIN : /* one side tries to close */
1050 case BOTH_SYN | (TH_FIN << 8) :
1051 if (tcp) {
1052 uint32_t ack = ntohl(tcp->th_ack);
1053
1054 #define _SEQ_GE(a, b) ((int)(a) - (int)(b) >= 0)
1055
1056 if (dir == MATCH_FORWARD) {
1057 if (q->ack_fwd == 0 ||
1058 _SEQ_GE(ack, q->ack_fwd))
1059 q->ack_fwd = ack;
1060 else /* ignore out-of-sequence */
1061 break;
1062 } else {
1063 if (q->ack_rev == 0 ||
1064 _SEQ_GE(ack, q->ack_rev))
1065 q->ack_rev = ack;
1066 else /* ignore out-of-sequence */
1067 break;
1068 }
1069 #undef _SEQ_GE
1070 }
1071 q->expire = time_second + dyn_ack_lifetime;
1072 break;
1073
1074 case BOTH_SYN | BOTH_FIN: /* both sides closed */
1075 KKASSERT(dyn_fin_lifetime < dyn_keepalive_period);
1076 q->expire = time_second + dyn_fin_lifetime;
1077 break;
1078
1079 default:
1080 #if 0
1081 /*
1082 * reset or some invalid combination, but can also
1083 * occur if we use keep-state the wrong way.
1084 */
1085 if ((q->state & ((TH_RST << 8) | TH_RST)) == 0)
1086 kprintf("invalid state: 0x%x\n", q->state);
1087 #endif
1088 KKASSERT(dyn_rst_lifetime < dyn_keepalive_period);
1089 q->expire = time_second + dyn_rst_lifetime;
1090 break;
1091 }
1092 } else if (pkt->proto == IPPROTO_UDP) {
1093 q->expire = time_second + dyn_udp_lifetime;
1094 } else {
1095 /* other protocols */
1096 q->expire = time_second + dyn_short_lifetime;
1097 }
1098 done:
1099 if (match_direction)
1100 *match_direction = dir;
1101 return q;
1102 }
1103
1104 static struct ip_fw *
1105 lookup_rule(struct ipfw_flow_id *pkt, int *match_direction, struct tcphdr *tcp,
1106 uint16_t len, int *deny)
1107 {
1108 struct ip_fw *rule = NULL;
1109 ipfw_dyn_rule *q;
1110 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
1111 uint32_t gen;
1112
1113 *deny = 0;
1114 gen = ctx->ipfw_gen;
1115
1116 lockmgr(&dyn_lock, LK_SHARED);
1117
1118 if (ctx->ipfw_gen != gen) {
1119 /*
1120 * Static rules had been change when we were waiting
1121 * for the dynamic hash table lock; deny this packet,
1122 * since it is _not_ known whether it is safe to keep
1123 * iterating the static rules.
1124 */
1125 *deny = 1;
1126 goto back;
1127 }
1128
1129 q = lookup_dyn_rule(pkt, match_direction, tcp);
1130 if (q == NULL) {
1131 rule = NULL;
1132 } else {
1133 rule = q->stub->rule[mycpuid];
1134 KKASSERT(rule->stub == q->stub && rule->cpuid == mycpuid);
1135
1136 /* XXX */
1137 q->pcnt++;
1138 q->bcnt += len;
1139 }
1140 back:
1141 lockmgr(&dyn_lock, LK_RELEASE);
1142 return rule;
1143 }
1144
1145 static void
1146 realloc_dynamic_table(void)
1147 {
1148 ipfw_dyn_rule **old_dyn_v;
1149 uint32_t old_curr_dyn_buckets;
1150
1151 KASSERT(dyn_buckets <= 65536 && (dyn_buckets & (dyn_buckets - 1)) == 0,
1152 ("invalid dyn_buckets %d\n", dyn_buckets));
1153
1154 /* Save the current buckets array for later error recovery */
1155 old_dyn_v = ipfw_dyn_v;
1156 old_curr_dyn_buckets = curr_dyn_buckets;
1157
1158 curr_dyn_buckets = dyn_buckets;
1159 for (;;) {
1160 ipfw_dyn_v = kmalloc(curr_dyn_buckets * sizeof(ipfw_dyn_rule *),
1161 M_IPFW, M_NOWAIT | M_ZERO);
1162 if (ipfw_dyn_v != NULL || curr_dyn_buckets <= 2)
1163 break;
1164
1165 curr_dyn_buckets /= 2;
1166 if (curr_dyn_buckets <= old_curr_dyn_buckets &&
1167 old_dyn_v != NULL) {
1168 /*
1169 * Don't try allocating smaller buckets array, reuse
1170 * the old one, which alreay contains enough buckets
1171 */
1172 break;
1173 }
1174 }
1175
1176 if (ipfw_dyn_v != NULL) {
1177 if (old_dyn_v != NULL)
1178 kfree(old_dyn_v, M_IPFW);
1179 } else {
1180 /* Allocation failed, restore old buckets array */
1181 ipfw_dyn_v = old_dyn_v;
1182 curr_dyn_buckets = old_curr_dyn_buckets;
1183 }
1184
1185 if (ipfw_dyn_v != NULL)
1186 ++dyn_buckets_gen;
1187 }
1188
1189 /**
1190 * Install state of type 'type' for a dynamic session.
1191 * The hash table contains two type of rules:
1192 * - regular rules (O_KEEP_STATE)
1193 * - rules for sessions with limited number of sess per user
1194 * (O_LIMIT). When they are created, the parent is
1195 * increased by 1, and decreased on delete. In this case,
1196 * the third parameter is the parent rule and not the chain.
1197 * - "parent" rules for the above (O_LIMIT_PARENT).
1198 */
1199 static ipfw_dyn_rule *
1200 add_dyn_rule(struct ipfw_flow_id *id, uint8_t dyn_type, struct ip_fw *rule)
1201 {
1202 ipfw_dyn_rule *r;
1203 int i;
1204
1205 if (ipfw_dyn_v == NULL ||
1206 (dyn_count == 0 && dyn_buckets != curr_dyn_buckets)) {
1207 realloc_dynamic_table();
1208 if (ipfw_dyn_v == NULL)
1209 return NULL; /* failed ! */
1210 }
1211 i = hash_packet(id);
1212
1213 r = kmalloc(sizeof(*r), M_IPFW, M_NOWAIT | M_ZERO);
1214 if (r == NULL) {
1215 kprintf ("sorry cannot allocate state\n");
1216 return NULL;
1217 }
1218
1219 /* increase refcount on parent, and set pointer */
1220 if (dyn_type == O_LIMIT) {
1221 ipfw_dyn_rule *parent = (ipfw_dyn_rule *)rule;
1222
1223 if (parent->dyn_type != O_LIMIT_PARENT)
1224 panic("invalid parent");
1225 parent->count++;
1226 r->parent = parent;
1227 rule = parent->stub->rule[mycpuid];
1228 KKASSERT(rule->stub == parent->stub);
1229 }
1230 KKASSERT(rule->cpuid == mycpuid && rule->stub != NULL);
1231
1232 r->id = *id;
1233 r->expire = time_second + dyn_syn_lifetime;
1234 r->stub = rule->stub;
1235 r->dyn_type = dyn_type;
1236 r->pcnt = r->bcnt = 0;
1237 r->count = 0;
1238
1239 r->bucket = i;
1240 r->next = ipfw_dyn_v[i];
1241 ipfw_dyn_v[i] = r;
1242 dyn_count++;
1243 dyn_buckets_gen++;
1244 DPRINTF("-- add dyn entry ty %d 0x%08x %d -> 0x%08x %d, total %d\n",
1245 dyn_type,
1246 r->id.src_ip, r->id.src_port,
1247 r->id.dst_ip, r->id.dst_port, dyn_count);
1248 return r;
1249 }
1250
1251 /**
1252 * lookup dynamic parent rule using pkt and rule as search keys.
1253 * If the lookup fails, then install one.
1254 */
1255 static ipfw_dyn_rule *
1256 lookup_dyn_parent(struct ipfw_flow_id *pkt, struct ip_fw *rule)
1257 {
1258 ipfw_dyn_rule *q;
1259 int i;
1260
1261 if (ipfw_dyn_v) {
1262 i = hash_packet(pkt);
1263 for (q = ipfw_dyn_v[i]; q != NULL; q = q->next) {
1264 if (q->dyn_type == O_LIMIT_PARENT &&
1265 rule->stub == q->stub &&
1266 pkt->proto == q->id.proto &&
1267 pkt->src_ip == q->id.src_ip &&
1268 pkt->dst_ip == q->id.dst_ip &&
1269 pkt->src_port == q->id.src_port &&
1270 pkt->dst_port == q->id.dst_port) {
1271 q->expire = time_second + dyn_short_lifetime;
1272 DPRINTF("lookup_dyn_parent found 0x%p\n", q);
1273 return q;
1274 }
1275 }
1276 }
1277 return add_dyn_rule(pkt, O_LIMIT_PARENT, rule);
1278 }
1279
1280 /**
1281 * Install dynamic state for rule type cmd->o.opcode
1282 *
1283 * Returns 1 (failure) if state is not installed because of errors or because
1284 * session limitations are enforced.
1285 */
1286 static int
1287 install_state_locked(struct ip_fw *rule, ipfw_insn_limit *cmd,
1288 struct ip_fw_args *args)
1289 {
1290 static int last_log; /* XXX */
1291
1292 ipfw_dyn_rule *q;
1293
1294 DPRINTF("-- install state type %d 0x%08x %u -> 0x%08x %u\n",
1295 cmd->o.opcode,
1296 args->f_id.src_ip, args->f_id.src_port,
1297 args->f_id.dst_ip, args->f_id.dst_port);
1298
1299 q = lookup_dyn_rule(&args->f_id, NULL, NULL);
1300 if (q != NULL) { /* should never occur */
1301 if (last_log != time_second) {
1302 last_log = time_second;
1303 kprintf(" install_state: entry already present, done\n");
1304 }
1305 return 0;
1306 }
1307
1308 if (dyn_count >= dyn_max) {
1309 /*
1310 * Run out of slots, try to remove any expired rule.
1311 */
1312 remove_dyn_rule_locked(NULL, (ipfw_dyn_rule *)1);
1313 if (dyn_count >= dyn_max) {
1314 if (last_log != time_second) {
1315 last_log = time_second;
1316 kprintf("install_state: "
1317 "Too many dynamic rules\n");
1318 }
1319 return 1; /* cannot install, notify caller */
1320 }
1321 }
1322
1323 switch (cmd->o.opcode) {
1324 case O_KEEP_STATE: /* bidir rule */
1325 if (add_dyn_rule(&args->f_id, O_KEEP_STATE, rule) == NULL)
1326 return 1;
1327 break;
1328
1329 case O_LIMIT: /* limit number of sessions */
1330 {
1331 uint16_t limit_mask = cmd->limit_mask;
1332 struct ipfw_flow_id id;
1333 ipfw_dyn_rule *parent;
1334
1335 DPRINTF("installing dyn-limit rule %d\n",
1336 cmd->conn_limit);
1337
1338 id.dst_ip = id.src_ip = 0;
1339 id.dst_port = id.src_port = 0;
1340 id.proto = args->f_id.proto;
1341
1342 if (limit_mask & DYN_SRC_ADDR)
1343 id.src_ip = args->f_id.src_ip;
1344 if (limit_mask & DYN_DST_ADDR)
1345 id.dst_ip = args->f_id.dst_ip;
1346 if (limit_mask & DYN_SRC_PORT)
1347 id.src_port = args->f_id.src_port;
1348 if (limit_mask & DYN_DST_PORT)
1349 id.dst_port = args->f_id.dst_port;
1350
1351 parent = lookup_dyn_parent(&id, rule);
1352 if (parent == NULL) {
1353 kprintf("add parent failed\n");
1354 return 1;
1355 }
1356
1357 if (parent->count >= cmd->conn_limit) {
1358 /*
1359 * See if we can remove some expired rule.
1360 */
1361 remove_dyn_rule_locked(rule, parent);
1362 if (parent->count >= cmd->conn_limit) {
1363 if (fw_verbose &&
1364 last_log != time_second) {
1365 last_log = time_second;
1366 log(LOG_SECURITY | LOG_DEBUG,
1367 "drop session, "
1368 "too many entries\n");
1369 }
1370 return 1;
1371 }
1372 }
1373 if (add_dyn_rule(&args->f_id, O_LIMIT,
1374 (struct ip_fw *)parent) == NULL)
1375 return 1;
1376 }
1377 break;
1378 default:
1379 kprintf("unknown dynamic rule type %u\n", cmd->o.opcode);
1380 return 1;
1381 }
1382 lookup_dyn_rule(&args->f_id, NULL, NULL); /* XXX just set lifetime */
1383 return 0;
1384 }
1385
1386 static int
1387 install_state(struct ip_fw *rule, ipfw_insn_limit *cmd,
1388 struct ip_fw_args *args, int *deny)
1389 {
1390 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
1391 uint32_t gen;
1392 int ret = 0;
1393
1394 *deny = 0;
1395 gen = ctx->ipfw_gen;
1396
1397 lockmgr(&dyn_lock, LK_EXCLUSIVE);
1398 if (ctx->ipfw_gen != gen) {
1399 /* See the comment in lookup_rule() */
1400 *deny = 1;
1401 } else {
1402 ret = install_state_locked(rule, cmd, args);
1403 }
1404 lockmgr(&dyn_lock, LK_RELEASE);
1405
1406 return ret;
1407 }
1408
1409 /*
1410 * Transmit a TCP packet, containing either a RST or a keepalive.
1411 * When flags & TH_RST, we are sending a RST packet, because of a
1412 * "reset" action matched the packet.
1413 * Otherwise we are sending a keepalive, and flags & TH_
1414 */
1415 static void
1416 send_pkt(struct ipfw_flow_id *id, uint32_t seq, uint32_t ack, int flags)
1417 {
1418 struct mbuf *m;
1419 struct ip *ip;
1420 struct tcphdr *tcp;
1421 struct route sro; /* fake route */
1422
1423 MGETHDR(m, MB_DONTWAIT, MT_HEADER);
1424 if (m == NULL)
1425 return;
1426 m->m_pkthdr.rcvif = NULL;
1427 m->m_pkthdr.len = m->m_len = sizeof(struct ip) + sizeof(struct tcphdr);
1428 m->m_data += max_linkhdr;
1429
1430 ip = mtod(m, struct ip *);
1431 bzero(ip, m->m_len);
1432 tcp = (struct tcphdr *)(ip + 1); /* no IP options */
1433 ip->ip_p = IPPROTO_TCP;
1434 tcp->th_off = 5;
1435
1436 /*
1437 * Assume we are sending a RST (or a keepalive in the reverse
1438 * direction), swap src and destination addresses and ports.
1439 */
1440 ip->ip_src.s_addr = htonl(id->dst_ip);
1441 ip->ip_dst.s_addr = htonl(id->src_ip);
1442 tcp->th_sport = htons(id->dst_port);
1443 tcp->th_dport = htons(id->src_port);
1444 if (flags & TH_RST) { /* we are sending a RST */
1445 if (flags & TH_ACK) {
1446 tcp->th_seq = htonl(ack);
1447 tcp->th_ack = htonl(0);
1448 tcp->th_flags = TH_RST;
1449 } else {
1450 if (flags & TH_SYN)
1451 seq++;
1452 tcp->th_seq = htonl(0);
1453 tcp->th_ack = htonl(seq);
1454 tcp->th_flags = TH_RST | TH_ACK;
1455 }
1456 } else {
1457 /*
1458 * We are sending a keepalive. flags & TH_SYN determines
1459 * the direction, forward if set, reverse if clear.
1460 * NOTE: seq and ack are always assumed to be correct
1461 * as set by the caller. This may be confusing...
1462 */
1463 if (flags & TH_SYN) {
1464 /*
1465 * we have to rewrite the correct addresses!
1466 */
1467 ip->ip_dst.s_addr = htonl(id->dst_ip);
1468 ip->ip_src.s_addr = htonl(id->src_ip);
1469 tcp->th_dport = htons(id->dst_port);
1470 tcp->th_sport = htons(id->src_port);
1471 }
1472 tcp->th_seq = htonl(seq);
1473 tcp->th_ack = htonl(ack);
1474 tcp->th_flags = TH_ACK;
1475 }
1476
1477 /*
1478 * set ip_len to the payload size so we can compute
1479 * the tcp checksum on the pseudoheader
1480 * XXX check this, could save a couple of words ?
1481 */
1482 ip->ip_len = htons(sizeof(struct tcphdr));
1483 tcp->th_sum = in_cksum(m, m->m_pkthdr.len);
1484
1485 /*
1486 * now fill fields left out earlier
1487 */
1488 ip->ip_ttl = ip_defttl;
1489 ip->ip_len = m->m_pkthdr.len;
1490
1491 bzero(&sro, sizeof(sro));
1492 ip_rtaddr(ip->ip_dst, &sro);
1493
1494 m->m_pkthdr.fw_flags |= IPFW_MBUF_GENERATED;
1495 ip_output(m, NULL, &sro, 0, NULL, NULL);
1496 if (sro.ro_rt)
1497 RTFREE(sro.ro_rt);
1498 }
1499
1500 /*
1501 * sends a reject message, consuming the mbuf passed as an argument.
1502 */
1503 static void
1504 send_reject(struct ip_fw_args *args, int code, int offset, int ip_len)
1505 {
1506 if (code != ICMP_REJECT_RST) { /* Send an ICMP unreach */
1507 /* We need the IP header in host order for icmp_error(). */
1508 if (args->eh != NULL) {
1509 struct ip *ip = mtod(args->m, struct ip *);
1510
1511 ip->ip_len = ntohs(ip->ip_len);
1512 ip->ip_off = ntohs(ip->ip_off);
1513 }
1514 icmp_error(args->m, ICMP_UNREACH, code, 0L, 0);
1515 } else if (offset == 0 && args->f_id.proto == IPPROTO_TCP) {
1516 struct tcphdr *const tcp =
1517 L3HDR(struct tcphdr, mtod(args->m, struct ip *));
1518
1519 if ((tcp->th_flags & TH_RST) == 0) {
1520 send_pkt(&args->f_id, ntohl(tcp->th_seq),
1521 ntohl(tcp->th_ack), tcp->th_flags | TH_RST);
1522 }
1523 m_freem(args->m);
1524 } else {
1525 m_freem(args->m);
1526 }
1527 args->m = NULL;
1528 }
1529
1530 /**
1531 *
1532 * Given an ip_fw *, lookup_next_rule will return a pointer
1533 * to the next rule, which can be either the jump
1534 * target (for skipto instructions) or the next one in the list (in
1535 * all other cases including a missing jump target).
1536 * The result is also written in the "next_rule" field of the rule.
1537 * Backward jumps are not allowed, so start looking from the next
1538 * rule...
1539 *
1540 * This never returns NULL -- in case we do not have an exact match,
1541 * the next rule is returned. When the ruleset is changed,
1542 * pointers are flushed so we are always correct.
1543 */
1544
1545 static struct ip_fw *
1546 lookup_next_rule(struct ip_fw *me)
1547 {
1548 struct ip_fw *rule = NULL;
1549 ipfw_insn *cmd;
1550
1551 /* look for action, in case it is a skipto */
1552 cmd = ACTION_PTR(me);
1553 if (cmd->opcode == O_LOG)
1554 cmd += F_LEN(cmd);
1555 if (cmd->opcode == O_SKIPTO) {
1556 for (rule = me->next; rule; rule = rule->next) {
1557 if (rule->rulenum >= cmd->arg1)
1558 break;
1559 }
1560 }
1561 if (rule == NULL) /* failure or not a skipto */
1562 rule = me->next;
1563 me->next_rule = rule;
1564 return rule;
1565 }
1566
1567 static int
1568 _ipfw_match_uid(const struct ipfw_flow_id *fid, struct ifnet *oif,
1569 enum ipfw_opcodes opcode, uid_t uid)
1570 {
1571 struct in_addr src_ip, dst_ip;
1572 struct inpcbinfo *pi;
1573 int wildcard;
1574 struct inpcb *pcb;
1575
1576 if (fid->proto == IPPROTO_TCP) {
1577 wildcard = 0;
1578 pi = &tcbinfo[mycpuid];
1579 } else if (fid->proto == IPPROTO_UDP) {
1580 wildcard = 1;
1581 pi = &udbinfo;
1582 } else {
1583 return 0;
1584 }
1585
1586 /*
1587 * Values in 'fid' are in host byte order
1588 */
1589 dst_ip.s_addr = htonl(fid->dst_ip);
1590 src_ip.s_addr = htonl(fid->src_ip);
1591 if (oif) {
1592 pcb = in_pcblookup_hash(pi,
1593 dst_ip, htons(fid->dst_port),
1594 src_ip, htons(fid->src_port),
1595 wildcard, oif);
1596 } else {
1597 pcb = in_pcblookup_hash(pi,
1598 src_ip, htons(fid->src_port),
1599 dst_ip, htons(fid->dst_port),
1600 wildcard, NULL);
1601 }
1602 if (pcb == NULL || pcb->inp_socket == NULL)
1603 return 0;
1604
1605 if (opcode == O_UID) {
1606 #define socheckuid(a,b) ((a)->so_cred->cr_uid != (b))
1607 return !socheckuid(pcb->inp_socket, uid);
1608 #undef socheckuid
1609 } else {
1610 return groupmember(uid, pcb->inp_socket->so_cred);
1611 }
1612 }
1613
1614 static int
1615 ipfw_match_uid(const struct ipfw_flow_id *fid, struct ifnet *oif,
1616 enum ipfw_opcodes opcode, uid_t uid, int *deny)
1617 {
1618 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
1619 uint32_t gen;
1620 int match = 0;
1621
1622 *deny = 0;
1623 gen = ctx->ipfw_gen;
1624
1625 get_mplock();
1626 if (gen != ctx->ipfw_gen) {
1627 /* See the comment in lookup_rule() */
1628 *deny = 1;
1629 } else {
1630 match = _ipfw_match_uid(fid, oif, opcode, uid);
1631 }
1632 rel_mplock();
1633 return match;
1634 }
1635
1636 /*
1637 * The main check routine for the firewall.
1638 *
1639 * All arguments are in args so we can modify them and return them
1640 * back to the caller.
1641 *
1642 * Parameters:
1643 *
1644 * args->m (in/out) The packet; we set to NULL when/if we nuke it.
1645 * Starts with the IP header.
1646 * args->eh (in) Mac header if present, or NULL for layer3 packet.
1647 * args->oif Outgoing interface, or NULL if packet is incoming.
1648 * The incoming interface is in the mbuf. (in)
1649 *
1650 * args->rule Pointer to the last matching rule (in/out)
1651 * args->f_id Addresses grabbed from the packet (out)
1652 *
1653 * Return value:
1654 *
1655 * If the packet was denied/rejected and has been dropped, *m is equal
1656 * to NULL upon return.
1657 *
1658 * IP_FW_DENY the packet must be dropped.
1659 * IP_FW_PASS The packet is to be accepted and routed normally.
1660 * IP_FW_DIVERT Divert the packet to port (args->cookie)
1661 * IP_FW_TEE Tee the packet to port (args->cookie)
1662 * IP_FW_DUMMYNET Send the packet to pipe/queue (args->cookie)
1663 */
1664
1665 static int
1666 ipfw_chk(struct ip_fw_args *args)
1667 {
1668 /*
1669 * Local variables hold state during the processing of a packet.
1670 *
1671 * IMPORTANT NOTE: to speed up the processing of rules, there
1672 * are some assumption on the values of the variables, which
1673 * are documented here. Should you change them, please check
1674 * the implementation of the various instructions to make sure
1675 * that they still work.
1676 *
1677 * args->eh The MAC header. It is non-null for a layer2
1678 * packet, it is NULL for a layer-3 packet.
1679 *
1680 * m | args->m Pointer to the mbuf, as received from the caller.
1681 * It may change if ipfw_chk() does an m_pullup, or if it
1682 * consumes the packet because it calls send_reject().
1683 * XXX This has to change, so that ipfw_chk() never modifies
1684 * or consumes the buffer.
1685 * ip is simply an alias of the value of m, and it is kept
1686 * in sync with it (the packet is supposed to start with
1687 * the ip header).
1688 */
1689 struct mbuf *m = args->m;
1690 struct ip *ip = mtod(m, struct ip *);
1691
1692 /*
1693 * oif | args->oif If NULL, ipfw_chk has been called on the
1694 * inbound path (ether_input, ip_input).
1695 * If non-NULL, ipfw_chk has been called on the outbound path
1696 * (ether_output, ip_output).
1697 */
1698 struct ifnet *oif = args->oif;
1699
1700 struct ip_fw *f = NULL; /* matching rule */
1701 int retval = IP_FW_PASS;
1702 struct m_tag *mtag;
1703 struct divert_info *divinfo;
1704
1705 /*
1706 * hlen The length of the IPv4 header.
1707 * hlen >0 means we have an IPv4 packet.
1708 */
1709 u_int hlen = 0; /* hlen >0 means we have an IP pkt */
1710
1711 /*
1712 * offset The offset of a fragment. offset != 0 means that
1713 * we have a fragment at this offset of an IPv4 packet.
1714 * offset == 0 means that (if this is an IPv4 packet)
1715 * this is the first or only fragment.
1716 */
1717 u_short offset = 0;
1718
1719 /*
1720 * Local copies of addresses. They are only valid if we have
1721 * an IP packet.
1722 *
1723 * proto The protocol. Set to 0 for non-ip packets,
1724 * or to the protocol read from the packet otherwise.
1725 * proto != 0 means that we have an IPv4 packet.
1726 *
1727 * src_port, dst_port port numbers, in HOST format. Only
1728 * valid for TCP and UDP packets.
1729 *
1730 * src_ip, dst_ip ip addresses, in NETWORK format.
1731 * Only valid for IPv4 packets.
1732 */
1733 uint8_t proto;
1734 uint16_t src_port = 0, dst_port = 0; /* NOTE: host format */
1735 struct in_addr src_ip, dst_ip; /* NOTE: network format */
1736 uint16_t ip_len = 0;
1737
1738 /*
1739 * dyn_dir = MATCH_UNKNOWN when rules unchecked,
1740 * MATCH_NONE when checked and not matched (dyn_f = NULL),
1741 * MATCH_FORWARD or MATCH_REVERSE otherwise (dyn_f != NULL)
1742 */
1743 int dyn_dir = MATCH_UNKNOWN;
1744 struct ip_fw *dyn_f = NULL;
1745 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
1746
1747 if (m->m_pkthdr.fw_flags & IPFW_MBUF_GENERATED)
1748 return IP_FW_PASS; /* accept */
1749
1750 if (args->eh == NULL || /* layer 3 packet */
1751 (m->m_pkthdr.len >= sizeof(struct ip) &&
1752 ntohs(args->eh->ether_type) == ETHERTYPE_IP))
1753 hlen = ip->ip_hl << 2;
1754
1755 /*
1756 * Collect parameters into local variables for faster matching.
1757 */
1758 if (hlen == 0) { /* do not grab addresses for non-ip pkts */
1759 proto = args->f_id.proto = 0; /* mark f_id invalid */
1760 goto after_ip_checks;
1761 }
1762
1763 proto = args->f_id.proto = ip->ip_p;
1764 src_ip = ip->ip_src;
1765 dst_ip = ip->ip_dst;
1766 if (args->eh != NULL) { /* layer 2 packets are as on the wire */
1767 offset = ntohs(ip->ip_off) & IP_OFFMASK;
1768 ip_len = ntohs(ip->ip_len);
1769 } else {
1770 offset = ip->ip_off & IP_OFFMASK;
1771 ip_len = ip->ip_len;
1772 }
1773
1774 #define PULLUP_TO(len) \
1775 do { \
1776 if (m->m_len < (len)) { \
1777 args->m = m = m_pullup(m, (len));\
1778 if (m == NULL) \
1779 goto pullup_failed; \
1780 ip = mtod(m, struct ip *); \
1781 } \
1782 } while (0)
1783
1784 if (offset == 0) {
1785 switch (proto) {
1786 case IPPROTO_TCP:
1787 {
1788 struct tcphdr *tcp;
1789
1790 PULLUP_TO(hlen + sizeof(struct tcphdr));
1791 tcp = L3HDR(struct tcphdr, ip);
1792 dst_port = tcp->th_dport;
1793 src_port = tcp->th_sport;
1794 args->f_id.flags = tcp->th_flags;
1795 }
1796 break;
1797
1798 case IPPROTO_UDP:
1799 {
1800 struct udphdr *udp;
1801
1802 PULLUP_TO(hlen + sizeof(struct udphdr));
1803 udp = L3HDR(struct udphdr, ip);
1804 dst_port = udp->uh_dport;
1805 src_port = udp->uh_sport;
1806 }
1807 break;
1808
1809 case IPPROTO_ICMP:
1810 PULLUP_TO(hlen + 4); /* type, code and checksum. */
1811 args->f_id.flags = L3HDR(struct icmp, ip)->icmp_type;
1812 break;
1813
1814 default:
1815 break;
1816 }
1817 }
1818
1819 #undef PULLUP_TO
1820
1821 args->f_id.src_ip = ntohl(src_ip.s_addr);
1822 args->f_id.dst_ip = ntohl(dst_ip.s_addr);
1823 args->f_id.src_port = src_port = ntohs(src_port);
1824 args->f_id.dst_port = dst_port = ntohs(dst_port);
1825
1826 after_ip_checks:
1827 if (args->rule) {
1828 /*
1829 * Packet has already been tagged. Look for the next rule
1830 * to restart processing.
1831 *
1832 * If fw_one_pass != 0 then just accept it.
1833 * XXX should not happen here, but optimized out in
1834 * the caller.
1835 */
1836 if (fw_one_pass)
1837 return IP_FW_PASS;
1838
1839 /* This rule is being/has been flushed */
1840 if (ipfw_flushing)
1841 return IP_FW_DENY;
1842
1843 KASSERT(args->rule->cpuid == mycpuid,
1844 ("rule used on cpu%d\n", mycpuid));
1845
1846 /* This rule was deleted */
1847 if (args->rule->rule_flags & IPFW_RULE_F_INVALID)
1848 return IP_FW_DENY;
1849
1850 f = args->rule->next_rule;
1851 if (f == NULL)
1852 f = lookup_next_rule(args->rule);
1853 } else {
1854 /*
1855 * Find the starting rule. It can be either the first
1856 * one, or the one after divert_rule if asked so.
1857 */
1858 int skipto;
1859
1860 mtag = m_tag_find(m, PACKET_TAG_IPFW_DIVERT, NULL);
1861 if (mtag != NULL) {
1862 divinfo = m_tag_data(mtag);
1863 skipto = divinfo->skipto;
1864 } else {
1865 skipto = 0;
1866 }
1867
1868 f = ctx->ipfw_layer3_chain;
1869 if (args->eh == NULL && skipto != 0) {
1870 /* No skipto during rule flushing */
1871 if (ipfw_flushing)
1872 return IP_FW_DENY;
1873
1874 if (skipto >= IPFW_DEFAULT_RULE)
1875 return IP_FW_DENY; /* invalid */
1876
1877 while (f && f->rulenum <= skipto)
1878 f = f->next;
1879 if (f == NULL) /* drop packet */
1880 return IP_FW_DENY;
1881 } else if (ipfw_flushing) {
1882 /* Rules are being flushed; skip to default rule */
1883 f = ctx->ipfw_default_rule;
1884 }
1885 }
1886 if ((mtag = m_tag_find(m, PACKET_TAG_IPFW_DIVERT, NULL)) != NULL)
1887 m_tag_delete(m, mtag);
1888
1889 /*
1890 * Now scan the rules, and parse microinstructions for each rule.
1891 */
1892 for (; f; f = f->next) {
1893 int l, cmdlen;
1894 ipfw_insn *cmd;
1895 int skip_or; /* skip rest of OR block */
1896
1897 again:
1898 if (ctx->ipfw_set_disable & (1 << f->set))
1899 continue;
1900
1901 skip_or = 0;
1902 for (l = f->cmd_len, cmd = f->cmd; l > 0;
1903 l -= cmdlen, cmd += cmdlen) {
1904 int match, deny;
1905
1906 /*
1907 * check_body is a jump target used when we find a
1908 * CHECK_STATE, and need to jump to the body of
1909 * the target rule.
1910 */
1911
1912 check_body:
1913 cmdlen = F_LEN(cmd);
1914 /*
1915 * An OR block (insn_1 || .. || insn_n) has the
1916 * F_OR bit set in all but the last instruction.
1917 * The first match will set "skip_or", and cause
1918 * the following instructions to be skipped until
1919 * past the one with the F_OR bit clear.
1920 */
1921 if (skip_or) { /* skip this instruction */
1922 if ((cmd->len & F_OR) == 0)
1923 skip_or = 0; /* next one is good */
1924 continue;
1925 }
1926 match = 0; /* set to 1 if we succeed */
1927
1928 switch (cmd->opcode) {
1929 /*
1930 * The first set of opcodes compares the packet's
1931 * fields with some pattern, setting 'match' if a
1932 * match is found. At the end of the loop there is
1933 * logic to deal with F_NOT and F_OR flags associated
1934 * with the opcode.
1935 */
1936 case O_NOP:
1937 match = 1;
1938 break;
1939
1940 case O_FORWARD_MAC:
1941 kprintf("ipfw: opcode %d unimplemented\n",
1942 cmd->opcode);
1943 break;
1944
1945 case O_GID:
1946 case O_UID:
1947 /*
1948 * We only check offset == 0 && proto != 0,
1949 * as this ensures that we have an IPv4
1950 * packet with the ports info.
1951 */
1952 if (offset!=0)
1953 break;
1954
1955 match = ipfw_match_uid(&args->f_id, oif,
1956 cmd->opcode,
1957 (uid_t)((ipfw_insn_u32 *)cmd)->d[0],
1958 &deny);
1959 if (deny)
1960 return IP_FW_DENY;
1961 break;
1962
1963 case O_RECV:
1964 match = iface_match(m->m_pkthdr.rcvif,
1965 (ipfw_insn_if *)cmd);
1966 break;
1967
1968 case O_XMIT:
1969 match = iface_match(oif, (ipfw_insn_if *)cmd);
1970 break;
1971
1972 case O_VIA:
1973 match = iface_match(oif ? oif :
1974 m->m_pkthdr.rcvif, (ipfw_insn_if *)cmd);
1975 break;
1976
1977 case O_MACADDR2:
1978 if (args->eh != NULL) { /* have MAC header */
1979 uint32_t *want = (uint32_t *)
1980 ((ipfw_insn_mac *)cmd)->addr;
1981 uint32_t *mask = (uint32_t *)
1982 ((ipfw_insn_mac *)cmd)->mask;
1983 uint32_t *hdr = (uint32_t *)args->eh;
1984
1985 match =
1986 (want[0] == (hdr[0] & mask[0]) &&
1987 want[1] == (hdr[1] & mask[1]) &&
1988 want[2] == (hdr[2] & mask[2]));
1989 }
1990 break;
1991
1992 case O_MAC_TYPE:
1993 if (args->eh != NULL) {
1994 uint16_t t =
1995 ntohs(args->eh->ether_type);
1996 uint16_t *p =
1997 ((ipfw_insn_u16 *)cmd)->ports;
1998 int i;
1999
2000 /* Special vlan handling */
2001 if (m->m_flags & M_VLANTAG)
2002 t = ETHERTYPE_VLAN;
2003
2004 for (i = cmdlen - 1; !match && i > 0;
2005 i--, p += 2) {
2006 match =
2007 (t >= p[0] && t <= p[1]);
2008 }
2009 }
2010 break;
2011
2012 case O_FRAG:
2013 match = (hlen > 0 && offset != 0);
2014 break;
2015
2016 case O_IN: /* "out" is "not in" */
2017 match = (oif == NULL);
2018 break;
2019
2020 case O_LAYER2:
2021 match = (args->eh != NULL);
2022 break;
2023
2024 case O_PROTO:
2025 /*
2026 * We do not allow an arg of 0 so the
2027 * check of "proto" only suffices.
2028 */
2029 match = (proto == cmd->arg1);
2030 break;
2031
2032 case O_IP_SRC:
2033 match = (hlen > 0 &&
2034 ((ipfw_insn_ip *)cmd)->addr.s_addr ==
2035 src_ip.s_addr);
2036 break;
2037
2038 case O_IP_SRC_MASK:
2039 match = (hlen > 0 &&
2040 ((ipfw_insn_ip *)cmd)->addr.s_addr ==
2041 (src_ip.s_addr &
2042 ((ipfw_insn_ip *)cmd)->mask.s_addr));
2043 break;
2044
2045 case O_IP_SRC_ME:
2046 if (hlen > 0) {
2047 struct ifnet *tif;
2048
2049 tif = INADDR_TO_IFP(&src_ip);
2050 match = (tif != NULL);
2051 }
2052 break;
2053
2054 case O_IP_DST_SET:
2055 case O_IP_SRC_SET:
2056 if (hlen > 0) {
2057 uint32_t *d = (uint32_t *)(cmd + 1);
2058 uint32_t addr =
2059 cmd->opcode == O_IP_DST_SET ?
2060 args->f_id.dst_ip :
2061 args->f_id.src_ip;
2062
2063 if (addr < d[0])
2064 break;
2065 addr -= d[0]; /* subtract base */
2066 match =
2067 (addr < cmd->arg1) &&
2068 (d[1 + (addr >> 5)] &
2069 (1 << (addr & 0x1f)));
2070 }
2071 break;
2072
2073 case O_IP_DST:
2074 match = (hlen > 0 &&
2075 ((ipfw_insn_ip *)cmd)->addr.s_addr ==
2076 dst_ip.s_addr);
2077 break;
2078
2079 case O_IP_DST_MASK:
2080 match = (hlen > 0) &&
2081 (((ipfw_insn_ip *)cmd)->addr.s_addr ==
2082 (dst_ip.s_addr &
2083 ((ipfw_insn_ip *)cmd)->mask.s_addr));
2084 break;
2085
2086 case O_IP_DST_ME:
2087 if (hlen > 0) {
2088 struct ifnet *tif;
2089
2090 tif = INADDR_TO_IFP(&dst_ip);
2091 match = (tif != NULL);
2092 }
2093 break;
2094
2095 case O_IP_SRCPORT:
2096 case O_IP_DSTPORT:
2097 /*
2098 * offset == 0 && proto != 0 is enough
2099 * to guarantee that we have an IPv4
2100 * packet with port info.
2101 */
2102 if ((proto==IPPROTO_UDP || proto==IPPROTO_TCP)
2103 && offset == 0) {
2104 uint16_t x =
2105 (cmd->opcode == O_IP_SRCPORT) ?
2106 src_port : dst_port ;
2107 uint16_t *p =
2108 ((ipfw_insn_u16 *)cmd)->ports;
2109 int i;
2110
2111 for (i = cmdlen - 1; !match && i > 0;
2112 i--, p += 2) {
2113 match =
2114 (x >= p[0] && x <= p[1]);
2115 }
2116 }
2117 break;
2118
2119 case O_ICMPTYPE:
2120 match = (offset == 0 && proto==IPPROTO_ICMP &&
2121 icmptype_match(ip, (ipfw_insn_u32 *)cmd));
2122 break;
2123
2124 case O_IPOPT:
2125 match = (hlen > 0 && ipopts_match(ip, cmd));
2126 break;
2127
2128 case O_IPVER:
2129 match = (hlen > 0 && cmd->arg1 == ip->ip_v);
2130 break;
2131
2132 case O_IPTTL:
2133 match = (hlen > 0 && cmd->arg1 == ip->ip_ttl);
2134 break;
2135
2136 case O_IPID:
2137 match = (hlen > 0 &&
2138 cmd->arg1 == ntohs(ip->ip_id));
2139 break;
2140
2141 case O_IPLEN:
2142 match = (hlen > 0 && cmd->arg1 == ip_len);
2143 break;
2144
2145 case O_IPPRECEDENCE:
2146 match = (hlen > 0 &&
2147 (cmd->arg1 == (ip->ip_tos & 0xe0)));
2148 break;
2149
2150 case O_IPTOS:
2151 match = (hlen > 0 &&
2152 flags_match(cmd, ip->ip_tos));
2153 break;
2154
2155 case O_TCPFLAGS:
2156 match = (proto == IPPROTO_TCP && offset == 0 &&
2157 flags_match(cmd,
2158 L3HDR(struct tcphdr,ip)->th_flags));
2159 break;
2160
2161 case O_TCPOPTS:
2162 match = (proto == IPPROTO_TCP && offset == 0 &&
2163 tcpopts_match(ip, cmd));
2164 break;
2165
2166 case O_TCPSEQ:
2167 match = (proto == IPPROTO_TCP && offset == 0 &&
2168 ((ipfw_insn_u32 *)cmd)->d[0] ==
2169 L3HDR(struct tcphdr,ip)->th_seq);
2170 break;
2171
2172 case O_TCPACK:
2173 match = (proto == IPPROTO_TCP && offset == 0 &&
2174 ((ipfw_insn_u32 *)cmd)->d[0] ==
2175 L3HDR(struct tcphdr,ip)->th_ack);
2176 break;
2177
2178 case O_TCPWIN:
2179 match = (proto == IPPROTO_TCP && offset == 0 &&
2180 cmd->arg1 ==
2181 L3HDR(struct tcphdr,ip)->th_win);
2182 break;
2183
2184 case O_ESTAB:
2185 /* reject packets which have SYN only */
2186 /* XXX should i also check for TH_ACK ? */
2187 match = (proto == IPPROTO_TCP && offset == 0 &&
2188 (L3HDR(struct tcphdr,ip)->th_flags &
2189 (TH_RST | TH_ACK | TH_SYN)) != TH_SYN);
2190 break;
2191
2192 case O_LOG:
2193 if (fw_verbose)
2194 ipfw_log(f, hlen, args->eh, m, oif);
2195 match = 1;
2196 break;
2197
2198 case O_PROB:
2199 match = (krandom() <
2200 ((ipfw_insn_u32 *)cmd)->d[0]);
2201 break;
2202
2203 /*
2204 * The second set of opcodes represents 'actions',
2205 * i.e. the terminal part of a rule once the packet
2206 * matches all previous patterns.
2207 * Typically there is only one action for each rule,
2208 * and the opcode is stored at the end of the rule
2209 * (but there are exceptions -- see below).
2210 *
2211 * In general, here we set retval and terminate the
2212 * outer loop (would be a 'break 3' in some language,
2213 * but we need to do a 'goto done').
2214 *
2215 * Exceptions:
2216 * O_COUNT and O_SKIPTO actions:
2217 * instead of terminating, we jump to the next rule
2218 * ('goto next_rule', equivalent to a 'break 2'),
2219 * or to the SKIPTO target ('goto again' after
2220 * having set f, cmd and l), respectively.
2221 *
2222 * O_LIMIT and O_KEEP_STATE: these opcodes are
2223 * not real 'actions', and are stored right
2224 * before the 'action' part of the rule.
2225 * These opcodes try to install an entry in the
2226 * state tables; if successful, we continue with
2227 * the next opcode (match=1; break;), otherwise
2228 * the packet must be dropped ('goto done' after
2229 * setting retval). If static rules are changed
2230 * during the state installation, the packet will
2231 * be dropped and rule's stats will not beupdated
2232 * ('return IP_FW_DENY').
2233 *
2234 * O_PROBE_STATE and O_CHECK_STATE: these opcodes
2235 * cause a lookup of the state table, and a jump
2236 * to the 'action' part of the parent rule
2237 * ('goto check_body') if an entry is found, or
2238 * (CHECK_STATE only) a jump to the next rule if
2239 * the entry is not found ('goto next_rule').
2240 * The result of the lookup is cached to make
2241 * further instances of these opcodes are
2242 * effectively NOPs. If static rules are changed
2243 * during the state looking up, the packet will
2244 * be dropped and rule's stats will not be updated
2245 * ('return IP_FW_DENY').
2246 */
2247 case O_LIMIT:
2248 case O_KEEP_STATE:
2249 if (!(f->rule_flags & IPFW_RULE_F_STATE)) {
2250 kprintf("%s rule (%d) is not ready "
2251 "on cpu%d\n",
2252 cmd->opcode == O_LIMIT ?
2253 "limit" : "keep state",
2254 f->rulenum, f->cpuid);
2255 goto next_rule;
2256 }
2257 if (install_state(f,
2258 (ipfw_insn_limit *)cmd, args, &deny)) {
2259 if (deny)
2260 return IP_FW_DENY;
2261
2262 retval = IP_FW_DENY;
2263 goto done; /* error/limit violation */
2264 }
2265 if (deny)
2266 return IP_FW_DENY;
2267 match = 1;
2268 break;
2269
2270 case O_PROBE_STATE:
2271 case O_CHECK_STATE:
2272 /*
2273 * dynamic rules are checked at the first
2274 * keep-state or check-state occurrence,
2275 * with the result being stored in dyn_dir.
2276 * The compiler introduces a PROBE_STATE
2277 * instruction for us when we have a
2278 * KEEP_STATE (because PROBE_STATE needs
2279 * to be run first).
2280 */
2281 if (dyn_dir == MATCH_UNKNOWN) {
2282 dyn_f = lookup_rule(&args->f_id,
2283 &dyn_dir,
2284 proto == IPPROTO_TCP ?
2285 L3HDR(struct tcphdr, ip) : NULL,
2286 ip_len, &deny);
2287 if (deny)
2288 return IP_FW_DENY;
2289 if (dyn_f != NULL) {
2290 /*
2291 * Found a rule from a dynamic
2292 * entry; jump to the 'action'
2293 * part of the rule.
2294 */
2295 f = dyn_f;
2296 cmd = ACTION_PTR(f);
2297 l = f->cmd_len - f->act_ofs;
2298 goto check_body;
2299 }
2300 }
2301 /*
2302 * Dynamic entry not found. If CHECK_STATE,
2303 * skip to next rule, if PROBE_STATE just
2304 * ignore and continue with next opcode.
2305 */
2306 if (cmd->opcode == O_CHECK_STATE)
2307 goto next_rule;
2308 else if (!(f->rule_flags & IPFW_RULE_F_STATE))
2309 goto next_rule; /* not ready yet */
2310 match = 1;
2311 break;
2312
2313 case O_ACCEPT:
2314 retval = IP_FW_PASS; /* accept */
2315 goto done;
2316
2317 case O_PIPE:
2318 case O_QUEUE:
2319 args->rule = f; /* report matching rule */
2320 args->cookie = cmd->arg1;
2321 retval = IP_FW_DUMMYNET;
2322 goto done;
2323
2324 case O_DIVERT:
2325 case O_TEE:
2326 if (args->eh) /* not on layer 2 */
2327 break;
2328
2329 mtag = m_tag_get(PACKET_TAG_IPFW_DIVERT,
2330 sizeof(*divinfo), MB_DONTWAIT);
2331 if (mtag == NULL) {
2332 retval = IP_FW_DENY;
2333 goto done;
2334 }
2335 divinfo = m_tag_data(mtag);
2336
2337 divinfo->skipto = f->rulenum;
2338 divinfo->port = cmd->arg1;
2339 divinfo->tee = (cmd->opcode == O_TEE);
2340 m_tag_prepend(m, mtag);
2341
2342 args->cookie = cmd->arg1;
2343 retval = (cmd->opcode == O_DIVERT) ?
2344 IP_FW_DIVERT : IP_FW_TEE;
2345 goto done;
2346
2347 case O_COUNT:
2348 case O_SKIPTO:
2349 f->pcnt++; /* update stats */
2350 f->bcnt += ip_len;
2351 f->timestamp = time_second;
2352 if (cmd->opcode == O_COUNT)
2353 goto next_rule;
2354 /* handle skipto */
2355 if (f->next_rule == NULL)
2356 lookup_next_rule(f);
2357 f = f->next_rule;
2358 goto again;
2359
2360 case O_REJECT:
2361 /*
2362 * Drop the packet and send a reject notice
2363 * if the packet is not ICMP (or is an ICMP
2364 * query), and it is not multicast/broadcast.
2365 */
2366 if (hlen > 0 &&
2367 (proto != IPPROTO_ICMP ||
2368 is_icmp_query(ip)) &&
2369 !(m->m_flags & (M_BCAST|M_MCAST)) &&
2370 !IN_MULTICAST(ntohl(dst_ip.s_addr))) {
2371 /*
2372 * Update statistics before the possible
2373 * blocking 'send_reject'
2374 */
2375 f->pcnt++;
2376 f->bcnt += ip_len;
2377 f->timestamp = time_second;
2378
2379 send_reject(args, cmd->arg1,
2380 offset,ip_len);
2381 m = args->m;
2382
2383 /*
2384 * Return directly here, rule stats
2385 * have been updated above.
2386 */
2387 return IP_FW_DENY;
2388 }
2389 /* FALLTHROUGH */
2390 case O_DENY:
2391 retval = IP_FW_DENY;
2392 goto done;
2393
2394 case O_FORWARD_IP:
2395 if (args->eh) /* not valid on layer2 pkts */
2396 break;
2397 if (!dyn_f || dyn_dir == MATCH_FORWARD) {
2398 struct sockaddr_in *sin;
2399
2400 mtag = m_tag_get(PACKET_TAG_IPFORWARD,
2401 sizeof(*sin), MB_DONTWAIT);
2402 if (mtag == NULL) {
2403 retval = IP_FW_DENY;
2404 goto done;
2405 }
2406 sin = m_tag_data(mtag);
2407
2408 /* Structure copy */
2409 *sin = ((ipfw_insn_sa *)cmd)->sa;
2410
2411 m_tag_prepend(m, mtag);
2412 m->m_pkthdr.fw_flags |=
2413 IPFORWARD_MBUF_TAGGED;
2414 }
2415 retval = IP_FW_PASS;
2416 goto done;
2417
2418 default:
2419 panic("-- unknown opcode %d\n", cmd->opcode);
2420 } /* end of switch() on opcodes */
2421
2422 if (cmd->len & F_NOT)
2423 match = !match;
2424
2425 if (match) {
2426 if (cmd->len & F_OR)
2427 skip_or = 1;
2428 } else {
2429 if (!(cmd->len & F_OR)) /* not an OR block, */
2430 break; /* try next rule */
2431 }
2432
2433 } /* end of inner for, scan opcodes */
2434
2435 next_rule:; /* try next rule */
2436
2437 } /* end of outer for, scan rules */
2438 kprintf("+++ ipfw: ouch!, skip past end of rules, denying packet\n");
2439 return IP_FW_DENY;
2440
2441 done:
2442 /* Update statistics */
2443 f->pcnt++;
2444 f->bcnt += ip_len;
2445 f->timestamp = time_second;
2446 return retval;
2447
2448 pullup_failed:
2449 if (fw_verbose)
2450 kprintf("pullup failed\n");
2451 return IP_FW_DENY;
2452 }
2453
2454 static void
2455 ipfw_dummynet_io(struct mbuf *m, int pipe_nr, int dir, struct ip_fw_args *fwa)
2456 {
2457 struct m_tag *mtag;
2458 struct dn_pkt *pkt;
2459 ipfw_insn *cmd;
2460 const struct ipfw_flow_id *id;
2461 struct dn_flow_id *fid;
2462
2463 M_ASSERTPKTHDR(m);
2464
2465 mtag = m_tag_get(PACKET_TAG_DUMMYNET, sizeof(*pkt), MB_DONTWAIT);
2466 if (mtag == NULL) {
2467 m_freem(m);
2468 return;
2469 }
2470 m_tag_prepend(m, mtag);
2471
2472 pkt = m_tag_data(mtag);
2473 bzero(pkt, sizeof(*pkt));
2474
2475 cmd = fwa->rule->cmd + fwa->rule->act_ofs;
2476 if (cmd->opcode == O_LOG)
2477 cmd += F_LEN(cmd);
2478 KASSERT(cmd->opcode == O_PIPE || cmd->opcode == O_QUEUE,
2479 ("Rule is not PIPE or QUEUE, opcode %d\n", cmd->opcode));
2480
2481 pkt->dn_m = m;
2482 pkt->dn_flags = (dir & DN_FLAGS_DIR_MASK);
2483 pkt->ifp = fwa->oif;
2484 pkt->pipe_nr = pipe_nr;
2485
2486 pkt->cpuid = mycpuid;
2487 pkt->msgport = curnetport;
2488
2489 id = &fwa->f_id;
2490 fid = &pkt->id;
2491 fid->fid_dst_ip = id->dst_ip;
2492 fid->fid_src_ip = id->src_ip;
2493 fid->fid_dst_port = id->dst_port;
2494 fid->fid_src_port = id->src_port;
2495 fid->fid_proto = id->proto;
2496 fid->fid_flags = id->flags;
2497
2498 ipfw_ref_rule(fwa->rule);
2499 pkt->dn_priv = fwa->rule;
2500 pkt->dn_unref_priv = ipfw_unref_rule;
2501
2502 if (cmd->opcode == O_PIPE)
2503 pkt->dn_flags |= DN_FLAGS_IS_PIPE;
2504
2505 m->m_pkthdr.fw_flags |= DUMMYNET_MBUF_TAGGED;
2506 }
2507
2508 /*
2509 * When a rule is added/deleted, clear the next_rule pointers in all rules.
2510 * These will be reconstructed on the fly as packets are matched.
2511 * Must be called at splimp().
2512 */
2513 static void
2514 ipfw_flush_rule_ptrs(struct ipfw_context *ctx)
2515 {
2516 struct ip_fw *rule;
2517
2518 for (rule = ctx->ipfw_layer3_chain; rule; rule = rule->next)
2519 rule->next_rule = NULL;
2520 }
2521
2522 static __inline void
2523 ipfw_inc_static_count(struct ip_fw *rule)
2524 {
2525 /* Static rule's counts are updated only on CPU0 */
2526 KKASSERT(mycpuid == 0);
2527
2528 static_count++;
2529 static_ioc_len += IOC_RULESIZE(rule);
2530 }
2531
2532 static __inline void
2533 ipfw_dec_static_count(struct ip_fw *rule)
2534 {
2535 int l = IOC_RULESIZE(rule);
2536
2537 /* Static rule's counts are updated only on CPU0 */
2538 KKASSERT(mycpuid == 0);
2539
2540 KASSERT(static_count > 0, ("invalid static count %u\n", static_count));
2541 static_count--;
2542
2543 KASSERT(static_ioc_len >= l,
2544 ("invalid static len %u\n", static_ioc_len));
2545 static_ioc_len -= l;
2546 }
2547
2548 static void
2549 ipfw_link_sibling(struct netmsg_ipfw *fwmsg, struct ip_fw *rule)
2550 {
2551 if (fwmsg->sibling != NULL) {
2552 KKASSERT(mycpuid > 0 && fwmsg->sibling->cpuid == mycpuid - 1);
2553 fwmsg->sibling->sibling = rule;
2554 }
2555 fwmsg->sibling = rule;
2556 }
2557
2558 static struct ip_fw *
2559 ipfw_create_rule(const struct ipfw_ioc_rule *ioc_rule, struct ip_fw_stub *stub)
2560 {
2561 struct ip_fw *rule;
2562
2563 rule = kmalloc(RULESIZE(ioc_rule), M_IPFW, M_WAITOK | M_ZERO);
2564
2565 rule->act_ofs = ioc_rule->act_ofs;
2566 rule->cmd_len = ioc_rule->cmd_len;
2567 rule->rulenum = ioc_rule->rulenum;
2568 rule->set = ioc_rule->set;
2569 rule->usr_flags = ioc_rule->usr_flags;
2570
2571 bcopy(ioc_rule->cmd, rule->cmd, rule->cmd_len * 4 /* XXX */);
2572
2573 rule->refcnt = 1;
2574 rule->cpuid = mycpuid;
2575
2576 rule->stub = stub;
2577 if (stub != NULL)
2578 stub->rule[mycpuid] = rule;
2579
2580 return rule;
2581 }
2582
2583 static void
2584 ipfw_add_rule_dispatch(struct netmsg *nmsg)
2585 {
2586 struct netmsg_ipfw *fwmsg = (struct netmsg_ipfw *)nmsg;
2587 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
2588 struct ip_fw *rule;
2589
2590 rule = ipfw_create_rule(fwmsg->ioc_rule, fwmsg->stub);
2591
2592 /*
2593 * Bump generation after ipfw_create_rule(),
2594 * since this function is blocking
2595 */
2596 ctx->ipfw_gen++;
2597
2598 /*
2599 * Insert rule into the pre-determined position
2600 */
2601 if (fwmsg->prev_rule != NULL) {
2602 struct ip_fw *prev, *next;
2603
2604 prev = fwmsg->prev_rule;
2605 KKASSERT(prev->cpuid == mycpuid);
2606
2607 next = fwmsg->next_rule;
2608 KKASSERT(next->cpuid == mycpuid);
2609
2610 rule->next = next;
2611 prev->next = rule;
2612
2613 /*
2614 * Move to the position on the next CPU
2615 * before the msg is forwarded.
2616 */
2617 fwmsg->prev_rule = prev->sibling;
2618 fwmsg->next_rule = next->sibling;
2619 } else {
2620 KKASSERT(fwmsg->next_rule == NULL);
2621 rule->next = ctx->ipfw_layer3_chain;
2622 ctx->ipfw_layer3_chain = rule;
2623 }
2624
2625 /* Link rule CPU sibling */
2626 ipfw_link_sibling(fwmsg, rule);
2627
2628 ipfw_flush_rule_ptrs(ctx);
2629
2630 if (mycpuid == 0) {
2631 /* Statistics only need to be updated once */
2632 ipfw_inc_static_count(rule);
2633
2634 /* Return the rule on CPU0 */
2635 nmsg->nm_lmsg.u.ms_resultp = rule;
2636 }
2637
2638 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
2639 }
2640
2641 static void
2642 ipfw_enable_state_dispatch(struct netmsg *nmsg)
2643 {
2644 struct lwkt_msg *lmsg = &nmsg->nm_lmsg;
2645 struct ip_fw *rule = lmsg->u.ms_resultp;
2646 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
2647
2648 ctx->ipfw_gen++;
2649
2650 KKASSERT(rule->cpuid == mycpuid);
2651 KKASSERT(rule->stub != NULL && rule->stub->rule[mycpuid] == rule);
2652 KKASSERT(!(rule->rule_flags & IPFW_RULE_F_STATE));
2653 rule->rule_flags |= IPFW_RULE_F_STATE;
2654 lmsg->u.ms_resultp = rule->sibling;
2655
2656 ifnet_forwardmsg(lmsg, mycpuid + 1);
2657 }
2658
2659 /*
2660 * Add a new rule to the list. Copy the rule into a malloc'ed area,
2661 * then possibly create a rule number and add the rule to the list.
2662 * Update the rule_number in the input struct so the caller knows
2663 * it as well.
2664 */
2665 static void
2666 ipfw_add_rule(struct ipfw_ioc_rule *ioc_rule, uint32_t rule_flags)
2667 {
2668 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
2669 struct netmsg_ipfw fwmsg;
2670 struct netmsg *nmsg;
2671 struct ip_fw *f, *prev, *rule;
2672 struct ip_fw_stub *stub;
2673
2674 IPFW_ASSERT_CFGPORT(&curthread->td_msgport);
2675
2676 /*
2677 * If rulenum is 0, find highest numbered rule before the
2678 * default rule, and add rule number incremental step.
2679 */
2680 if (ioc_rule->rulenum == 0) {
2681 int step = autoinc_step;
2682
2683 KKASSERT(step >= IPFW_AUTOINC_STEP_MIN &&
2684 step <= IPFW_AUTOINC_STEP_MAX);
2685
2686 /*
2687 * Locate the highest numbered rule before default
2688 */
2689 for (f = ctx->ipfw_layer3_chain; f; f = f->next) {
2690 if (f->rulenum == IPFW_DEFAULT_RULE)
2691 break;
2692 ioc_rule->rulenum = f->rulenum;
2693 }
2694 if (ioc_rule->rulenum < IPFW_DEFAULT_RULE - step)
2695 ioc_rule->rulenum += step;
2696 }
2697 KASSERT(ioc_rule->rulenum != IPFW_DEFAULT_RULE &&
2698 ioc_rule->rulenum != 0,
2699 ("invalid rule num %d\n", ioc_rule->rulenum));
2700
2701 /*
2702 * Now find the right place for the new rule in the sorted list.
2703 */
2704 for (prev = NULL, f = ctx->ipfw_layer3_chain; f;
2705 prev = f, f = f->next) {
2706 if (f->rulenum > ioc_rule->rulenum) {
2707 /* Found the location */
2708 break;
2709 }
2710 }
2711 KASSERT(f != NULL, ("no default rule?!\n"));
2712
2713 if (rule_flags & IPFW_RULE_F_STATE) {
2714 int size;
2715
2716 /*
2717 * If the new rule will create states, then allocate
2718 * a rule stub, which will be referenced by states
2719 * (dyn rules)
2720 */
2721 size = sizeof(*stub) + ((ncpus - 1) * sizeof(struct ip_fw *));
2722 stub = kmalloc(size, M_IPFW, M_WAITOK | M_ZERO);
2723 } else {
2724 stub = NULL;
2725 }
2726
2727 /*
2728 * Duplicate the rule onto each CPU.
2729 * The rule duplicated on CPU0 will be returned.
2730 */
2731 bzero(&fwmsg, sizeof(fwmsg));
2732 nmsg = &fwmsg.nmsg;
2733 netmsg_init(nmsg, NULL, &curthread->td_msgport,
2734 0, ipfw_add_rule_dispatch);
2735 fwmsg.ioc_rule = ioc_rule;
2736 fwmsg.prev_rule = prev;
2737 fwmsg.next_rule = prev == NULL ? NULL : f;
2738 fwmsg.stub = stub;
2739
2740 ifnet_domsg(&nmsg->nm_lmsg, 0);
2741 KKASSERT(fwmsg.prev_rule == NULL && fwmsg.next_rule == NULL);
2742
2743 rule = nmsg->nm_lmsg.u.ms_resultp;
2744 KKASSERT(rule != NULL && rule->cpuid == mycpuid);
2745
2746 if (rule_flags & IPFW_RULE_F_STATE) {
2747 /*
2748 * Turn on state flag, _after_ everything on all
2749 * CPUs have been setup.
2750 */
2751 bzero(nmsg, sizeof(*nmsg));
2752 netmsg_init(nmsg, NULL, &curthread->td_msgport,
2753 0, ipfw_enable_state_dispatch);
2754 nmsg->nm_lmsg.u.ms_resultp = rule;
2755
2756 ifnet_domsg(&nmsg->nm_lmsg, 0);
2757 KKASSERT(nmsg->nm_lmsg.u.ms_resultp == NULL);
2758 }
2759
2760 DPRINTF("++ installed rule %d, static count now %d\n",
2761 rule->rulenum, static_count);
2762 }
2763
2764 /**
2765 * Free storage associated with a static rule (including derived
2766 * dynamic rules).
2767 * The caller is in charge of clearing rule pointers to avoid
2768 * dangling pointers.
2769 * @return a pointer to the next entry.
2770 * Arguments are not checked, so they better be correct.
2771 * Must be called at splimp().
2772 */
2773 static struct ip_fw *
2774 ipfw_delete_rule(struct ipfw_context *ctx,
2775 struct ip_fw *prev, struct ip_fw *rule)
2776 {
2777 struct ip_fw *n;
2778 struct ip_fw_stub *stub;
2779
2780 ctx->ipfw_gen++;
2781
2782 /* STATE flag should have been cleared before we reach here */
2783 KKASSERT((rule->rule_flags & IPFW_RULE_F_STATE) == 0);
2784
2785 stub = rule->stub;
2786 n = rule->next;
2787 if (prev == NULL)
2788 ctx->ipfw_layer3_chain = n;
2789 else
2790 prev->next = n;
2791
2792 /* Mark the rule as invalid */
2793 rule->rule_flags |= IPFW_RULE_F_INVALID;
2794 rule->next_rule = NULL;
2795 rule->sibling = NULL;
2796 rule->stub = NULL;
2797 #ifdef foo
2798 /* Don't reset cpuid here; keep various assertion working */
2799 rule->cpuid = -1;
2800 #endif
2801
2802 /* Statistics only need to be updated once */
2803 if (mycpuid == 0)
2804 ipfw_dec_static_count(rule);
2805
2806 /* Free 'stub' on the last CPU */
2807 if (stub != NULL && mycpuid == ncpus - 1)
2808 kfree(stub, M_IPFW);
2809
2810 /* Try to free this rule */
2811 ipfw_free_rule(rule);
2812
2813 /* Return the next rule */
2814 return n;
2815 }
2816
2817 static void
2818 ipfw_flush_dispatch(struct netmsg *nmsg)
2819 {
2820 struct lwkt_msg *lmsg = &nmsg->nm_lmsg;
2821 int kill_default = lmsg->u.ms_result;
2822 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
2823 struct ip_fw *rule;
2824
2825 ipfw_flush_rule_ptrs(ctx); /* more efficient to do outside the loop */
2826
2827 while ((rule = ctx->ipfw_layer3_chain) != NULL &&
2828 (kill_default || rule->rulenum != IPFW_DEFAULT_RULE))
2829 ipfw_delete_rule(ctx, NULL, rule);
2830
2831 ifnet_forwardmsg(lmsg, mycpuid + 1);
2832 }
2833
2834 static void
2835 ipfw_disable_rule_state_dispatch(struct netmsg *nmsg)
2836 {
2837 struct netmsg_del *dmsg = (struct netmsg_del *)nmsg;
2838 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
2839 struct ip_fw *rule;
2840
2841 ctx->ipfw_gen++;
2842
2843 rule = dmsg->start_rule;
2844 if (rule != NULL) {
2845 KKASSERT(rule->cpuid == mycpuid);
2846
2847 /*
2848 * Move to the position on the next CPU
2849 * before the msg is forwarded.
2850 */
2851 dmsg->start_rule = rule->sibling;
2852 } else {
2853 KKASSERT(dmsg->rulenum == 0);
2854 rule = ctx->ipfw_layer3_chain;
2855 }
2856
2857 while (rule != NULL) {
2858 if (dmsg->rulenum && rule->rulenum != dmsg->rulenum)
2859 break;
2860 rule->rule_flags &= ~IPFW_RULE_F_STATE;
2861 rule = rule->next;
2862 }
2863
2864 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
2865 }
2866
2867 /*
2868 * Deletes all rules from a chain (including the default rule
2869 * if the second argument is set).
2870 * Must be called at splimp().
2871 */
2872 static void
2873 ipfw_flush(int kill_default)
2874 {
2875 struct netmsg_del dmsg;
2876 struct netmsg nmsg;
2877 struct lwkt_msg *lmsg;
2878 struct ip_fw *rule;
2879 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
2880
2881 IPFW_ASSERT_CFGPORT(&curthread->td_msgport);
2882
2883 /*
2884 * If 'kill_default' then caller has done the necessary
2885 * msgport syncing; unnecessary to do it again.
2886 */
2887 if (!kill_default) {
2888 /*
2889 * Let ipfw_chk() know the rules are going to
2890 * be flushed, so it could jump directly to
2891 * the default rule.
2892 */
2893 ipfw_flushing = 1;
2894 netmsg_service_sync();
2895 }
2896
2897 /*
2898 * Clear STATE flag on rules, so no more states (dyn rules)
2899 * will be created.
2900 */
2901 bzero(&dmsg, sizeof(dmsg));
2902 netmsg_init(&dmsg.nmsg, NULL, &curthread->td_msgport,
2903 0, ipfw_disable_rule_state_dispatch);
2904 ifnet_domsg(&dmsg.nmsg.nm_lmsg, 0);
2905
2906 /*
2907 * This actually nukes all states (dyn rules)
2908 */
2909 lockmgr(&dyn_lock, LK_EXCLUSIVE);
2910 for (rule = ctx->ipfw_layer3_chain; rule != NULL; rule = rule->next) {
2911 /*
2912 * Can't check IPFW_RULE_F_STATE here,
2913 * since it has been cleared previously.
2914 * Check 'stub' instead.
2915 */
2916 if (rule->stub != NULL) {
2917 /* Force removal */
2918 remove_dyn_rule_locked(rule, NULL);
2919 }
2920 }
2921 lockmgr(&dyn_lock, LK_RELEASE);
2922
2923 /*
2924 * Press the 'flush' button
2925 */
2926 bzero(&nmsg, sizeof(nmsg));
2927 netmsg_init(&nmsg, NULL, &curthread->td_msgport,
2928 0, ipfw_flush_dispatch);
2929 lmsg = &nmsg.nm_lmsg;
2930 lmsg->u.ms_result = kill_default;
2931 ifnet_domsg(lmsg, 0);
2932
2933 KASSERT(dyn_count == 0, ("%u dyn rule remains\n", dyn_count));
2934
2935 if (kill_default) {
2936 if (ipfw_dyn_v != NULL) {
2937 /*
2938 * Free dynamic rules(state) hash table
2939 */
2940 kfree(ipfw_dyn_v, M_IPFW);
2941 ipfw_dyn_v = NULL;
2942 }
2943
2944 KASSERT(static_count == 0,
2945 ("%u static rules remains\n", static_count));
2946 KASSERT(static_ioc_len == 0,
2947 ("%u bytes of static rules remains\n", static_ioc_len));
2948 } else {
2949 KASSERT(static_count == 1,
2950 ("%u static rules remains\n", static_count));
2951 KASSERT(static_ioc_len == IOC_RULESIZE(ctx->ipfw_default_rule),
2952 ("%u bytes of static rules remains, should be %lu\n",
2953 static_ioc_len,
2954 (u_long)IOC_RULESIZE(ctx->ipfw_default_rule)));
2955 }
2956
2957 /* Flush is done */
2958 ipfw_flushing = 0;
2959 }
2960
2961 static void
2962 ipfw_alt_delete_rule_dispatch(struct netmsg *nmsg)
2963 {
2964 struct netmsg_del *dmsg = (struct netmsg_del *)nmsg;
2965 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
2966 struct ip_fw *rule, *prev;
2967
2968 rule = dmsg->start_rule;
2969 KKASSERT(rule->cpuid == mycpuid);
2970 dmsg->start_rule = rule->sibling;
2971
2972 prev = dmsg->prev_rule;
2973 if (prev != NULL) {
2974 KKASSERT(prev->cpuid == mycpuid);
2975
2976 /*
2977 * Move to the position on the next CPU
2978 * before the msg is forwarded.
2979 */
2980 dmsg->prev_rule = prev->sibling;
2981 }
2982
2983 /*
2984 * flush pointers outside the loop, then delete all matching
2985 * rules. 'prev' remains the same throughout the cycle.
2986 */
2987 ipfw_flush_rule_ptrs(ctx);
2988 while (rule && rule->rulenum == dmsg->rulenum)
2989 rule = ipfw_delete_rule(ctx, prev, rule);
2990
2991 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
2992 }
2993
2994 static int
2995 ipfw_alt_delete_rule(uint16_t rulenum)
2996 {
2997 struct ip_fw *prev, *rule, *f;
2998 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
2999 struct netmsg_del dmsg;
3000 struct netmsg *nmsg;
3001 int state;
3002
3003 /*
3004 * Locate first rule to delete
3005 */
3006 for (prev = NULL, rule = ctx->ipfw_layer3_chain;
3007 rule && rule->rulenum < rulenum;
3008 prev = rule, rule = rule->next)
3009 ; /* EMPTY */
3010 if (rule->rulenum != rulenum)
3011 return EINVAL;
3012
3013 /*
3014 * Check whether any rules with the given number will
3015 * create states.
3016 */
3017 state = 0;
3018 for (f = rule; f && f->rulenum == rulenum; f = f->next) {
3019 if (f->rule_flags & IPFW_RULE_F_STATE) {
3020 state = 1;
3021 break;
3022 }
3023 }
3024
3025 if (state) {
3026 /*
3027 * Clear the STATE flag, so no more states will be
3028 * created based the rules numbered 'rulenum'.
3029 */
3030 bzero(&dmsg, sizeof(dmsg));
3031 nmsg = &dmsg.nmsg;
3032 netmsg_init(nmsg, NULL, &curthread->td_msgport,
3033 0, ipfw_disable_rule_state_dispatch);
3034 dmsg.start_rule = rule;
3035 dmsg.rulenum = rulenum;
3036
3037 ifnet_domsg(&nmsg->nm_lmsg, 0);
3038 KKASSERT(dmsg.start_rule == NULL);
3039
3040 /*
3041 * Nuke all related states
3042 */
3043 lockmgr(&dyn_lock, LK_EXCLUSIVE);
3044 for (f = rule; f && f->rulenum == rulenum; f = f->next) {
3045 /*
3046 * Can't check IPFW_RULE_F_STATE here,
3047 * since it has been cleared previously.
3048 * Check 'stub' instead.
3049 */
3050 if (f->stub != NULL) {
3051 /* Force removal */
3052 remove_dyn_rule_locked(f, NULL);
3053 }
3054 }
3055 lockmgr(&dyn_lock, LK_RELEASE);
3056 }
3057
3058 /*
3059 * Get rid of the rule duplications on all CPUs
3060 */
3061 bzero(&dmsg, sizeof(dmsg));
3062 nmsg = &dmsg.nmsg;
3063 netmsg_init(nmsg, NULL, &curthread->td_msgport,
3064 0, ipfw_alt_delete_rule_dispatch);
3065 dmsg.prev_rule = prev;
3066 dmsg.start_rule = rule;
3067 dmsg.rulenum = rulenum;
3068
3069 ifnet_domsg(&nmsg->nm_lmsg, 0);
3070 KKASSERT(dmsg.prev_rule == NULL && dmsg.start_rule == NULL);
3071 return 0;
3072 }
3073
3074 static void
3075 ipfw_alt_delete_ruleset_dispatch(struct netmsg *nmsg)
3076 {
3077 struct netmsg_del *dmsg = (struct netmsg_del *)nmsg;
3078 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3079 struct ip_fw *prev, *rule;
3080 #ifdef INVARIANTS
3081 int del = 0;
3082 #endif
3083
3084 ipfw_flush_rule_ptrs(ctx);
3085
3086 prev = NULL;
3087 rule = ctx->ipfw_layer3_chain;
3088 while (rule != NULL) {
3089 if (rule->set == dmsg->from_set) {
3090 rule = ipfw_delete_rule(ctx, prev, rule);
3091 #ifdef INVARIANTS
3092 del = 1;
3093 #endif
3094 } else {
3095 prev = rule;
3096 rule = rule->next;
3097 }
3098 }
3099 KASSERT(del, ("no match set?!\n"));
3100
3101 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
3102 }
3103
3104 static void
3105 ipfw_disable_ruleset_state_dispatch(struct netmsg *nmsg)
3106 {
3107 struct netmsg_del *dmsg = (struct netmsg_del *)nmsg;
3108 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3109 struct ip_fw *rule;
3110 #ifdef INVARIANTS
3111 int cleared = 0;
3112 #endif
3113
3114 ctx->ipfw_gen++;
3115
3116 for (rule = ctx->ipfw_layer3_chain; rule; rule = rule->next) {
3117 if (rule->set == dmsg->from_set) {
3118 #ifdef INVARIANTS
3119 cleared = 1;
3120 #endif
3121 rule->rule_flags &= ~IPFW_RULE_F_STATE;
3122 }
3123 }
3124 KASSERT(cleared, ("no match set?!\n"));
3125
3126 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
3127 }
3128
3129 static int
3130 ipfw_alt_delete_ruleset(uint8_t set)
3131 {
3132 struct netmsg_del dmsg;
3133 struct netmsg *nmsg;
3134 int state, del;
3135 struct ip_fw *rule;
3136 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3137
3138 /*
3139 * Check whether the 'set' exists. If it exists,
3140 * then check whether any rules within the set will
3141 * try to create states.
3142 */
3143 state = 0;
3144 del = 0;
3145 for (rule = ctx->ipfw_layer3_chain; rule; rule = rule->next) {
3146 if (rule->set == set) {
3147 del = 1;
3148 if (rule->rule_flags & IPFW_RULE_F_STATE) {
3149 state = 1;
3150 break;
3151 }
3152 }
3153 }
3154 if (!del)
3155 return 0; /* XXX EINVAL? */
3156
3157 if (state) {
3158 /*
3159 * Clear the STATE flag, so no more states will be
3160 * created based the rules in this set.
3161 */
3162 bzero(&dmsg, sizeof(dmsg));
3163 nmsg = &dmsg.nmsg;
3164 netmsg_init(nmsg, NULL, &curthread->td_msgport,
3165 0, ipfw_disable_ruleset_state_dispatch);
3166 dmsg.from_set = set;
3167
3168 ifnet_domsg(&nmsg->nm_lmsg, 0);
3169
3170 /*
3171 * Nuke all related states
3172 */
3173 lockmgr(&dyn_lock, LK_EXCLUSIVE);
3174 for (rule = ctx->ipfw_layer3_chain; rule; rule = rule->next) {
3175 if (rule->set != set)
3176 continue;
3177
3178 /*
3179 * Can't check IPFW_RULE_F_STATE here,
3180 * since it has been cleared previously.
3181 * Check 'stub' instead.
3182 */
3183 if (rule->stub != NULL) {
3184 /* Force removal */
3185 remove_dyn_rule_locked(rule, NULL);
3186 }
3187 }
3188 lockmgr(&dyn_lock, LK_RELEASE);
3189 }
3190
3191 /*
3192 * Delete this set
3193 */
3194 bzero(&dmsg, sizeof(dmsg));
3195 nmsg = &dmsg.nmsg;
3196 netmsg_init(nmsg, NULL, &curthread->td_msgport,
3197 0, ipfw_alt_delete_ruleset_dispatch);
3198 dmsg.from_set = set;
3199
3200 ifnet_domsg(&nmsg->nm_lmsg, 0);
3201 return 0;
3202 }
3203
3204 static void
3205 ipfw_alt_move_rule_dispatch(struct netmsg *nmsg)
3206 {
3207 struct netmsg_del *dmsg = (struct netmsg_del *)nmsg;
3208 struct ip_fw *rule;
3209
3210 rule = dmsg->start_rule;
3211 KKASSERT(rule->cpuid == mycpuid);
3212
3213 /*
3214 * Move to the position on the next CPU
3215 * before the msg is forwarded.
3216 */
3217 dmsg->start_rule = rule->sibling;
3218
3219 while (rule && rule->rulenum <= dmsg->rulenum) {
3220 if (rule->rulenum == dmsg->rulenum)
3221 rule->set = dmsg->to_set;
3222 rule = rule->next;
3223 }
3224 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
3225 }
3226
3227 static int
3228 ipfw_alt_move_rule(uint16_t rulenum, uint8_t set)
3229 {
3230 struct netmsg_del dmsg;
3231 struct netmsg *nmsg;
3232 struct ip_fw *rule;
3233 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3234
3235 /*
3236 * Locate first rule to move
3237 */
3238 for (rule = ctx->ipfw_layer3_chain; rule && rule->rulenum <= rulenum;
3239 rule = rule->next) {
3240 if (rule->rulenum == rulenum && rule->set != set)
3241 break;
3242 }
3243 if (rule == NULL || rule->rulenum > rulenum)
3244 return 0; /* XXX error? */
3245
3246 bzero(&dmsg, sizeof(dmsg));
3247 nmsg = &dmsg.nmsg;
3248 netmsg_init(nmsg, NULL, &curthread->td_msgport,
3249 0, ipfw_alt_move_rule_dispatch);
3250 dmsg.start_rule = rule;
3251 dmsg.rulenum = rulenum;
3252 dmsg.to_set = set;
3253
3254 ifnet_domsg(&nmsg->nm_lmsg, 0);
3255 KKASSERT(dmsg.start_rule == NULL);
3256 return 0;
3257 }
3258
3259 static void
3260 ipfw_alt_move_ruleset_dispatch(struct netmsg *nmsg)
3261 {
3262 struct netmsg_del *dmsg = (struct netmsg_del *)nmsg;
3263 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3264 struct ip_fw *rule;
3265
3266 for (rule = ctx->ipfw_layer3_chain; rule; rule = rule->next) {
3267 if (rule->set == dmsg->from_set)
3268 rule->set = dmsg->to_set;
3269 }
3270 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
3271 }
3272
3273 static int
3274 ipfw_alt_move_ruleset(uint8_t from_set, uint8_t to_set)
3275 {
3276 struct netmsg_del dmsg;
3277 struct netmsg *nmsg;
3278
3279 bzero(&dmsg, sizeof(dmsg));
3280 nmsg = &dmsg.nmsg;
3281 netmsg_init(nmsg, NULL, &curthread->td_msgport,
3282 0, ipfw_alt_move_ruleset_dispatch);
3283 dmsg.from_set = from_set;
3284 dmsg.to_set = to_set;
3285
3286 ifnet_domsg(&nmsg->nm_lmsg, 0);
3287 return 0;
3288 }
3289
3290 static void
3291 ipfw_alt_swap_ruleset_dispatch(struct netmsg *nmsg)
3292 {
3293 struct netmsg_del *dmsg = (struct netmsg_del *)nmsg;
3294 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3295 struct ip_fw *rule;
3296
3297 for (rule = ctx->ipfw_layer3_chain; rule; rule = rule->next) {
3298 if (rule->set == dmsg->from_set)
3299 rule->set = dmsg->to_set;
3300 else if (rule->set == dmsg->to_set)
3301 rule->set = dmsg->from_set;
3302 }
3303 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
3304 }
3305
3306 static int
3307 ipfw_alt_swap_ruleset(uint8_t set1, uint8_t set2)
3308 {
3309 struct netmsg_del dmsg;
3310 struct netmsg *nmsg;
3311
3312 bzero(&dmsg, sizeof(dmsg));
3313 nmsg = &dmsg.nmsg;
3314 netmsg_init(nmsg, NULL, &curthread->td_msgport,
3315 0, ipfw_alt_swap_ruleset_dispatch);
3316 dmsg.from_set = set1;
3317 dmsg.to_set = set2;
3318
3319 ifnet_domsg(&nmsg->nm_lmsg, 0);
3320 return 0;
3321 }
3322
3323 /**
3324 * Remove all rules with given number, and also do set manipulation.
3325 *
3326 * The argument is an uint32_t. The low 16 bit are the rule or set number,
3327 * the next 8 bits are the new set, the top 8 bits are the command:
3328 *
3329 * 0 delete rules with given number
3330 * 1 delete rules with given set number
3331 * 2 move rules with given number to new set
3332 * 3 move rules with given set number to new set
3333 * 4 swap sets with given numbers
3334 */
3335 static int
3336 ipfw_ctl_alter(uint32_t arg)
3337 {
3338 uint16_t rulenum;
3339 uint8_t cmd, new_set;
3340 int error = 0;
3341
3342 rulenum = arg & 0xffff;
3343 cmd = (arg >> 24) & 0xff;
3344 new_set = (arg >> 16) & 0xff;
3345
3346 if (cmd > 4)
3347 return EINVAL;
3348 if (new_set >= IPFW_DEFAULT_SET)
3349 return EINVAL;
3350 if (cmd == 0 || cmd == 2) {
3351 if (rulenum == IPFW_DEFAULT_RULE)
3352 return EINVAL;
3353 } else {
3354 if (rulenum >= IPFW_DEFAULT_SET)
3355 return EINVAL;
3356 }
3357
3358 switch (cmd) {
3359 case 0: /* delete rules with given number */
3360 error = ipfw_alt_delete_rule(rulenum);
3361 break;
3362
3363 case 1: /* delete all rules with given set number */
3364 error = ipfw_alt_delete_ruleset(rulenum);
3365 break;
3366
3367 case 2: /* move rules with given number to new set */
3368 error = ipfw_alt_move_rule(rulenum, new_set);
3369 break;
3370
3371 case 3: /* move rules with given set number to new set */
3372 error = ipfw_alt_move_ruleset(rulenum, new_set);
3373 break;
3374
3375 case 4: /* swap two sets */
3376 error = ipfw_alt_swap_ruleset(rulenum, new_set);
3377 break;
3378 }
3379 return error;
3380 }
3381
3382 /*
3383 * Clear counters for a specific rule.
3384 */
3385 static void
3386 clear_counters(struct ip_fw *rule, int log_only)
3387 {
3388 ipfw_insn_log *l = (ipfw_insn_log *)ACTION_PTR(rule);
3389
3390 if (log_only == 0) {
3391 rule->bcnt = rule->pcnt = 0;
3392 rule->timestamp = 0;
3393 }
3394 if (l->o.opcode == O_LOG)
3395 l->log_left = l->max_log;
3396 }
3397
3398 static void
3399 ipfw_zero_entry_dispatch(struct netmsg *nmsg)
3400 {
3401 struct netmsg_zent *zmsg = (struct netmsg_zent *)nmsg;
3402 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3403 struct ip_fw *rule;
3404
3405 if (zmsg->rulenum == 0) {
3406 KKASSERT(zmsg->start_rule == NULL);
3407
3408 ctx->ipfw_norule_counter = 0;
3409 for (rule = ctx->ipfw_layer3_chain; rule; rule = rule->next)
3410 clear_counters(rule, zmsg->log_only);
3411 } else {
3412 struct ip_fw *start = zmsg->start_rule;
3413
3414 KKASSERT(start->cpuid == mycpuid);
3415 KKASSERT(start->rulenum == zmsg->rulenum);
3416
3417 /*
3418 * We can have multiple rules with the same number, so we
3419 * need to clear them all.
3420 */
3421 for (rule = start; rule && rule->rulenum == zmsg->rulenum;
3422 rule = rule->next)
3423 clear_counters(rule, zmsg->log_only);
3424
3425 /*
3426 * Move to the position on the next CPU
3427 * before the msg is forwarded.
3428 */
3429 zmsg->start_rule = start->sibling;
3430 }
3431 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
3432 }
3433
3434 /**
3435 * Reset some or all counters on firewall rules.
3436 * @arg frwl is null to clear all entries, or contains a specific
3437 * rule number.
3438 * @arg log_only is 1 if we only want to reset logs, zero otherwise.
3439 */
3440 static int
3441 ipfw_ctl_zero_entry(int rulenum, int log_only)
3442 {
3443 struct netmsg_zent zmsg;
3444 struct netmsg *nmsg;
3445 const char *msg;
3446 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3447
3448 bzero(&zmsg, sizeof(zmsg));
3449 nmsg = &zmsg.nmsg;
3450 netmsg_init(nmsg, NULL, &curthread->td_msgport,
3451 0, ipfw_zero_entry_dispatch);
3452 zmsg.log_only = log_only;
3453
3454 if (rulenum == 0) {
3455 msg = log_only ? "ipfw: All logging counts reset.\n"
3456 : "ipfw: Accounting cleared.\n";
3457 } else {
3458 struct ip_fw *rule;
3459
3460 /*
3461 * Locate the first rule with 'rulenum'
3462 */
3463 for (rule = ctx->ipfw_layer3_chain; rule; rule = rule->next) {
3464 if (rule->rulenum == rulenum)
3465 break;
3466 }
3467 if (rule == NULL) /* we did not find any matching rules */
3468 return (EINVAL);
3469 zmsg.start_rule = rule;
3470 zmsg.rulenum = rulenum;
3471
3472 msg = log_only ? "ipfw: Entry %d logging count reset.\n"
3473 : "ipfw: Entry %d cleared.\n";
3474 }
3475 ifnet_domsg(&nmsg->nm_lmsg, 0);
3476 KKASSERT(zmsg.start_rule == NULL);
3477
3478 if (fw_verbose)
3479 log(LOG_SECURITY | LOG_NOTICE, msg, rulenum);
3480 return (0);
3481 }
3482
3483 /*
3484 * Check validity of the structure before insert.
3485 * Fortunately rules are simple, so this mostly need to check rule sizes.
3486 */
3487 static int
3488 ipfw_check_ioc_rule(struct ipfw_ioc_rule *rule, int size, uint32_t *rule_flags)
3489 {
3490 int l, cmdlen = 0;
3491 int have_action = 0;
3492 ipfw_insn *cmd;
3493
3494 *rule_flags = 0;
3495
3496 /* Check for valid size */
3497 if (size < sizeof(*rule)) {
3498 kprintf("ipfw: rule too short\n");
3499 return EINVAL;
3500 }
3501 l = IOC_RULESIZE(rule);
3502 if (l != size) {
3503 kprintf("ipfw: size mismatch (have %d want %d)\n", size, l);
3504 return EINVAL;
3505 }
3506
3507 /* Check rule number */
3508 if (rule->rulenum == IPFW_DEFAULT_RULE) {
3509 kprintf("ipfw: invalid rule number\n");
3510 return EINVAL;
3511 }
3512
3513 /*
3514 * Now go for the individual checks. Very simple ones, basically only
3515 * instruction sizes.
3516 */
3517 for (l = rule->cmd_len, cmd = rule->cmd; l > 0;
3518 l -= cmdlen, cmd += cmdlen) {
3519 cmdlen = F_LEN(cmd);
3520 if (cmdlen > l) {
3521 kprintf("ipfw: opcode %d size truncated\n",
3522 cmd->opcode);
3523 return EINVAL;
3524 }
3525
3526 DPRINTF("ipfw: opcode %d\n", cmd->opcode);
3527
3528 if (cmd->opcode == O_KEEP_STATE || cmd->opcode == O_LIMIT) {
3529 /* This rule will create states */
3530 *rule_flags |= IPFW_RULE_F_STATE;
3531 }
3532
3533 switch (cmd->opcode) {
3534 case O_NOP:
3535 case O_PROBE_STATE:
3536 case O_KEEP_STATE:
3537 case O_PROTO:
3538 case O_IP_SRC_ME:
3539 case O_IP_DST_ME:
3540 case O_LAYER2:
3541 case O_IN:
3542 case O_FRAG:
3543 case O_IPOPT:
3544 case O_IPLEN:
3545 case O_IPID:
3546 case O_IPTOS:
3547 case O_IPPRECEDENCE:
3548 case O_IPTTL:
3549 case O_IPVER:
3550 case O_TCPWIN:
3551 case O_TCPFLAGS:
3552 case O_TCPOPTS:
3553 case O_ESTAB:
3554 if (cmdlen != F_INSN_SIZE(ipfw_insn))
3555 goto bad_size;
3556 break;
3557
3558 case O_UID:
3559 case O_GID:
3560 case O_IP_SRC:
3561 case O_IP_DST:
3562 case O_TCPSEQ:
3563 case O_TCPACK:
3564 case O_PROB:
3565 case O_ICMPTYPE:
3566 if (cmdlen != F_INSN_SIZE(ipfw_insn_u32))
3567 goto bad_size;
3568 break;
3569
3570 case O_LIMIT:
3571 if (cmdlen != F_INSN_SIZE(ipfw_insn_limit))
3572 goto bad_size;
3573 break;
3574
3575 case O_LOG:
3576 if (cmdlen != F_INSN_SIZE(ipfw_insn_log))
3577 goto bad_size;
3578
3579 ((ipfw_insn_log *)cmd)->log_left =
3580 ((ipfw_insn_log *)cmd)->max_log;
3581
3582 break;
3583
3584 case O_IP_SRC_MASK:
3585 case O_IP_DST_MASK:
3586 if (cmdlen != F_INSN_SIZE(ipfw_insn_ip))
3587 goto bad_size;
3588 if (((ipfw_insn_ip *)cmd)->mask.s_addr == 0) {
3589 kprintf("ipfw: opcode %d, useless rule\n",
3590 cmd->opcode);
3591 return EINVAL;
3592 }
3593 break;
3594
3595 case O_IP_SRC_SET:
3596 case O_IP_DST_SET:
3597 if (cmd->arg1 == 0 || cmd->arg1 > 256) {
3598 kprintf("ipfw: invalid set size %d\n",
3599 cmd->arg1);
3600 return EINVAL;
3601 }
3602 if (cmdlen != F_INSN_SIZE(ipfw_insn_u32) +
3603 (cmd->arg1+31)/32 )
3604 goto bad_size;
3605 break;
3606
3607 case O_MACADDR2:
3608 if (cmdlen != F_INSN_SIZE(ipfw_insn_mac))
3609 goto bad_size;
3610 break;
3611
3612 case O_MAC_TYPE:
3613 case O_IP_SRCPORT:
3614 case O_IP_DSTPORT: /* XXX artificial limit, 30 port pairs */
3615 if (cmdlen < 2 || cmdlen > 31)
3616 goto bad_size;
3617 break;
3618
3619 case O_RECV:
3620 case O_XMIT:
3621 case O_VIA:
3622 if (cmdlen != F_INSN_SIZE(ipfw_insn_if))
3623 goto bad_size;
3624 break;
3625
3626 case O_PIPE:
3627 case O_QUEUE:
3628 if (cmdlen != F_INSN_SIZE(ipfw_insn_pipe))
3629 goto bad_size;
3630 goto check_action;
3631
3632 case O_FORWARD_IP:
3633 if (cmdlen != F_INSN_SIZE(ipfw_insn_sa)) {
3634 goto bad_size;
3635 } else {
3636 in_addr_t fwd_addr;
3637
3638 fwd_addr = ((ipfw_insn_sa *)cmd)->
3639 sa.sin_addr.s_addr;
3640 if (IN_MULTICAST(ntohl(fwd_addr))) {
3641 kprintf("ipfw: try forwarding to "
3642 "multicast address\n");
3643 return EINVAL;
3644 }
3645 }
3646 goto check_action;
3647
3648 case O_FORWARD_MAC: /* XXX not implemented yet */
3649 case O_CHECK_STATE:
3650 case O_COUNT:
3651 case O_ACCEPT:
3652 case O_DENY:
3653 case O_REJECT:
3654 case O_SKIPTO:
3655 case O_DIVERT:
3656 case O_TEE:
3657 if (cmdlen != F_INSN_SIZE(ipfw_insn))
3658 goto bad_size;
3659 check_action:
3660 if (have_action) {
3661 kprintf("ipfw: opcode %d, multiple actions"
3662 " not allowed\n",
3663 cmd->opcode);
3664 return EINVAL;
3665 }
3666 have_action = 1;
3667 if (l != cmdlen) {
3668 kprintf("ipfw: opcode %d, action must be"
3669 " last opcode\n",
3670 cmd->opcode);
3671 return EINVAL;
3672 }
3673 break;
3674 default:
3675 kprintf("ipfw: opcode %d, unknown opcode\n",
3676 cmd->opcode);
3677 return EINVAL;
3678 }
3679 }
3680 if (have_action == 0) {
3681 kprintf("ipfw: missing action\n");
3682 return EINVAL;
3683 }
3684 return 0;
3685
3686 bad_size:
3687 kprintf("ipfw: opcode %d size %d wrong\n",
3688 cmd->opcode, cmdlen);
3689 return EINVAL;
3690 }
3691
3692 static int
3693 ipfw_ctl_add_rule(struct sockopt *sopt)
3694 {
3695 struct ipfw_ioc_rule *ioc_rule;
3696 size_t size;
3697 uint32_t rule_flags;
3698 int error;
3699
3700 size = sopt->sopt_valsize;
3701 if (size > (sizeof(uint32_t) * IPFW_RULE_SIZE_MAX) ||
3702 size < sizeof(*ioc_rule)) {
3703 return EINVAL;
3704 }
3705 if (size != (sizeof(uint32_t) * IPFW_RULE_SIZE_MAX)) {
3706 sopt->sopt_val = krealloc(sopt->sopt_val, sizeof(uint32_t) *
3707 IPFW_RULE_SIZE_MAX, M_TEMP, M_WAITOK);
3708 }
3709 ioc_rule = sopt->sopt_val;
3710
3711 error = ipfw_check_ioc_rule(ioc_rule, size, &rule_flags);
3712 if (error)
3713 return error;
3714
3715 ipfw_add_rule(ioc_rule, rule_flags);
3716
3717 if (sopt->sopt_dir == SOPT_GET)
3718 sopt->sopt_valsize = IOC_RULESIZE(ioc_rule);
3719 return 0;
3720 }
3721
3722 static void *
3723 ipfw_copy_rule(const struct ip_fw *rule, struct ipfw_ioc_rule *ioc_rule)
3724 {
3725 const struct ip_fw *sibling;
3726 #ifdef INVARIANTS
3727 int i;
3728 #endif
3729
3730 KKASSERT(rule->cpuid == IPFW_CFGCPUID);
3731
3732 ioc_rule->act_ofs = rule->act_ofs;
3733 ioc_rule->cmd_len = rule->cmd_len;
3734 ioc_rule->rulenum = rule->rulenum;
3735 ioc_rule->set = rule->set;
3736 ioc_rule->usr_flags = rule->usr_flags;
3737
3738 ioc_rule->set_disable = ipfw_ctx[mycpuid]->ipfw_set_disable;
3739 ioc_rule->static_count = static_count;
3740 ioc_rule->static_len = static_ioc_len;
3741
3742 /*
3743 * Visit (read-only) all of the rule's duplications to get
3744 * the necessary statistics
3745 */
3746 #ifdef INVARIANTS
3747 i = 0;
3748 #endif
3749 ioc_rule->pcnt = 0;
3750 ioc_rule->bcnt = 0;
3751 ioc_rule->timestamp = 0;
3752 for (sibling = rule; sibling != NULL; sibling = sibling->sibling) {
3753 ioc_rule->pcnt += sibling->pcnt;
3754 ioc_rule->bcnt += sibling->bcnt;
3755 if (sibling->timestamp > ioc_rule->timestamp)
3756 ioc_rule->timestamp = sibling->timestamp;
3757 #ifdef INVARIANTS
3758 ++i;
3759 #endif
3760 }
3761 KASSERT(i == ncpus, ("static rule is not duplicated on every cpu\n"));
3762
3763 bcopy(rule->cmd, ioc_rule->cmd, ioc_rule->cmd_len * 4 /* XXX */);
3764
3765 return ((uint8_t *)ioc_rule + IOC_RULESIZE(ioc_rule));
3766 }
3767
3768 static void
3769 ipfw_copy_state(const ipfw_dyn_rule *dyn_rule,
3770 struct ipfw_ioc_state *ioc_state)
3771 {
3772 const struct ipfw_flow_id *id;
3773 struct ipfw_ioc_flowid *ioc_id;
3774
3775 ioc_state->expire = TIME_LEQ(dyn_rule->expire, time_second) ?
3776 0 : dyn_rule->expire - time_second;
3777 ioc_state->pcnt = dyn_rule->pcnt;
3778 ioc_state->bcnt = dyn_rule->bcnt;
3779
3780 ioc_state->dyn_type = dyn_rule->dyn_type;
3781 ioc_state->count = dyn_rule->count;
3782
3783 ioc_state->rulenum = dyn_rule->stub->rule[mycpuid]->rulenum;
3784
3785 id = &dyn_rule->id;
3786 ioc_id = &ioc_state->id;
3787
3788 ioc_id->type = ETHERTYPE_IP;
3789 ioc_id->u.ip.dst_ip = id->dst_ip;
3790 ioc_id->u.ip.src_ip = id->src_ip;
3791 ioc_id->u.ip.dst_port = id->dst_port;
3792 ioc_id->u.ip.src_port = id->src_port;
3793 ioc_id->u.ip.proto = id->proto;
3794 }
3795
3796 static int
3797 ipfw_ctl_get_rules(struct sockopt *sopt)
3798 {
3799 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3800 struct ip_fw *rule;
3801 void *bp;
3802 size_t size;
3803 uint32_t dcount = 0;
3804
3805 /*
3806 * pass up a copy of the current rules. Static rules
3807 * come first (the last of which has number IPFW_DEFAULT_RULE),
3808 * followed by a possibly empty list of dynamic rule.
3809 */
3810
3811 size = static_ioc_len; /* size of static rules */
3812 if (ipfw_dyn_v) { /* add size of dyn.rules */
3813 dcount = dyn_count;
3814 size += dcount * sizeof(struct ipfw_ioc_state);
3815 }
3816
3817 if (sopt->sopt_valsize < size) {
3818 /* short length, no need to return incomplete rules */
3819 /* XXX: if superuser, no need to zero buffer */
3820 bzero(sopt->sopt_val, sopt->sopt_valsize);
3821 return 0;
3822 }
3823 bp = sopt->sopt_val;
3824
3825 for (rule = ctx->ipfw_layer3_chain; rule; rule = rule->next)
3826 bp = ipfw_copy_rule(rule, bp);
3827
3828 if (ipfw_dyn_v && dcount != 0) {
3829 struct ipfw_ioc_state *ioc_state = bp;
3830 uint32_t dcount2 = 0;
3831 #ifdef INVARIANTS
3832 size_t old_size = size;
3833 #endif
3834 int i;
3835
3836 lockmgr(&dyn_lock, LK_SHARED);
3837
3838 /* Check 'ipfw_dyn_v' again with lock held */
3839 if (ipfw_dyn_v == NULL)
3840 goto skip;
3841
3842 for (i = 0; i < curr_dyn_buckets; i++) {
3843 ipfw_dyn_rule *p;
3844
3845 /*
3846 * The # of dynamic rules may have grown after the
3847 * snapshot of 'dyn_count' was taken, so we will have
3848 * to check 'dcount' (snapshot of dyn_count) here to
3849 * make sure that we don't overflow the pre-allocated
3850 * buffer.
3851 */
3852 for (p = ipfw_dyn_v[i]; p != NULL && dcount != 0;
3853 p = p->next, ioc_state++, dcount--, dcount2++)
3854 ipfw_copy_state(p, ioc_state);
3855 }
3856 skip:
3857 lockmgr(&dyn_lock, LK_RELEASE);
3858
3859 /*
3860 * The # of dynamic rules may be shrinked after the
3861 * snapshot of 'dyn_count' was taken. To give user a
3862 * correct dynamic rule count, we use the 'dcount2'
3863 * calculated above (with shared lockmgr lock held).
3864 */
3865 size = static_ioc_len +
3866 (dcount2 * sizeof(struct ipfw_ioc_state));
3867 KKASSERT(size <= old_size);
3868 }
3869
3870 sopt->sopt_valsize = size;
3871 return 0;
3872 }
3873
3874 static void
3875 ipfw_set_disable_dispatch(struct netmsg *nmsg)
3876 {
3877 struct lwkt_msg *lmsg = &nmsg->nm_lmsg;
3878 struct ipfw_context *ctx = ipfw_ctx[mycpuid];
3879
3880 ctx->ipfw_gen++;
3881 ctx->ipfw_set_disable = lmsg->u.ms_result32;
3882
3883 ifnet_forwardmsg(lmsg, mycpuid + 1);
3884 }
3885
3886 static void
3887 ipfw_ctl_set_disable(uint32_t disable, uint32_t enable)
3888 {
3889 struct netmsg nmsg;
3890 struct lwkt_msg *lmsg;
3891 uint32_t set_disable;
3892
3893 /* IPFW_DEFAULT_SET is always enabled */
3894 enable |= (1 << IPFW_DEFAULT_SET);
3895 set_disable = (ipfw_ctx[mycpuid]->ipfw_set_disable | disable) & ~enable;
3896
3897 bzero(&nmsg, sizeof(nmsg));
3898 netmsg_init(&nmsg, NULL, &curthread->td_msgport,
3899 0, ipfw_set_disable_dispatch);
3900 lmsg = &nmsg.nm_lmsg;
3901 lmsg->u.ms_result32 = set_disable;
3902
3903 ifnet_domsg(lmsg, 0);
3904 }
3905
3906 /**
3907 * {set|get}sockopt parser.
3908 */
3909 static int
3910 ipfw_ctl(struct sockopt *sopt)
3911 {
3912 int error, rulenum;
3913 uint32_t *masks;
3914 size_t size;
3915
3916 error = 0;
3917
3918 switch (sopt->sopt_name) {
3919 case IP_FW_GET:
3920 error = ipfw_ctl_get_rules(sopt);
3921 break;
3922
3923 case IP_FW_FLUSH:
3924 ipfw_flush(0 /* keep default rule */);
3925 break;
3926
3927 case IP_FW_ADD:
3928 error = ipfw_ctl_add_rule(sopt);
3929 break;
3930
3931 case IP_FW_DEL:
3932 /*
3933 * IP_FW_DEL is used for deleting single rules or sets,
3934 * and (ab)used to atomically manipulate sets.
3935 * Argument size is used to distinguish between the two:
3936 * sizeof(uint32_t)
3937 * delete single rule or set of rules,
3938 * or reassign rules (or sets) to a different set.
3939 * 2 * sizeof(uint32_t)
3940 * atomic disable/enable sets.
3941 * first uint32_t contains sets to be disabled,
3942 * second uint32_t contains sets to be enabled.
3943 */
3944 masks = sopt->sopt_val;
3945 size = sopt->sopt_valsize;
3946 if (size == sizeof(*masks)) {
3947 /*
3948 * Delete or reassign static rule
3949 */
3950 error = ipfw_ctl_alter(masks[0]);
3951 } else if (size == (2 * sizeof(*masks))) {
3952 /*
3953 * Set enable/disable
3954 */
3955 ipfw_ctl_set_disable(masks[0], masks[1]);
3956 } else {
3957 error = EINVAL;
3958 }
3959 break;
3960
3961 case IP_FW_ZERO:
3962 case IP_FW_RESETLOG: /* argument is an int, the rule number */
3963 rulenum = 0;
3964
3965 if (sopt->sopt_val != 0) {
3966 error = soopt_to_kbuf(sopt, &rulenum,
3967 sizeof(int), sizeof(int));
3968 if (error)
3969 break;
3970 }
3971 error = ipfw_ctl_zero_entry(rulenum,
3972 sopt->sopt_name == IP_FW_RESETLOG);
3973 break;
3974
3975 default:
3976 kprintf("ipfw_ctl invalid option %d\n", sopt->sopt_name);
3977 error = EINVAL;
3978 }
3979 return error;
3980 }
3981
3982 /*
3983 * This procedure is only used to handle keepalives. It is invoked
3984 * every dyn_keepalive_period
3985 */
3986 static void
3987 ipfw_tick_dispatch(struct netmsg *nmsg)
3988 {
3989 time_t keep_alive;
3990 uint32_t gen;
3991 int i;
3992
3993 IPFW_ASSERT_CFGPORT(&curthread->td_msgport);
3994 KKASSERT(IPFW_LOADED);
3995
3996 /* Reply ASAP */
3997 crit_enter();
3998 lwkt_replymsg(&nmsg->nm_lmsg, 0);
3999 crit_exit();
4000
4001 if (ipfw_dyn_v == NULL || dyn_count == 0)
4002 goto done;
4003
4004 keep_alive = time_second;
4005
4006 lockmgr(&dyn_lock, LK_EXCLUSIVE);
4007 again:
4008 if (ipfw_dyn_v == NULL || dyn_count == 0) {
4009 lockmgr(&dyn_lock, LK_RELEASE);
4010 goto done;
4011 }
4012 gen = dyn_buckets_gen;
4013
4014 for (i = 0; i < curr_dyn_buckets; i++) {
4015 ipfw_dyn_rule *q, *prev;
4016
4017 for (prev = NULL, q = ipfw_dyn_v[i]; q != NULL;) {
4018 uint32_t ack_rev, ack_fwd;
4019 struct ipfw_flow_id id;
4020
4021 if (q->dyn_type == O_LIMIT_PARENT)
4022 goto next;
4023
4024 if (TIME_LEQ(q->expire, time_second)) {
4025 /* State expired */
4026 UNLINK_DYN_RULE(prev, ipfw_dyn_v[i], q);
4027 continue;
4028 }
4029
4030 /*
4031 * Keep alive processing
4032 */
4033
4034 if (!dyn_keepalive)
4035 goto next;
4036 if (q->id.proto != IPPROTO_TCP)
4037 goto next;
4038 if ((q->state & BOTH_SYN) != BOTH_SYN)
4039 goto next;
4040 if (TIME_LEQ(time_second + dyn_keepalive_interval,
4041 q->expire))
4042 goto next; /* too early */
4043 if (q->keep_alive == keep_alive)
4044 goto next; /* alreay done */
4045
4046 /*
4047 * Save necessary information, so that they could
4048 * survive after possible blocking in send_pkt()
4049 */
4050 id = q->id;
4051 ack_rev = q->ack_rev;
4052 ack_fwd = q->ack_fwd;
4053
4054 /* Sending has been started */
4055 q->keep_alive = keep_alive;
4056
4057 /* Release lock to avoid possible dead lock */
4058 lockmgr(&dyn_lock, LK_RELEASE);
4059 send_pkt(&id, ack_rev - 1, ack_fwd, TH_SYN);
4060 send_pkt(&id, ack_fwd - 1, ack_rev, 0);
4061 lockmgr(&dyn_lock, LK_EXCLUSIVE);
4062
4063 if (gen != dyn_buckets_gen) {
4064 /*
4065 * Dyn bucket array has been changed during
4066 * the above two sending; reiterate.
4067 */
4068 goto again;
4069 }
4070 next:
4071 prev = q;
4072 q = q->next;
4073 }
4074 }
4075 lockmgr(&dyn_lock, LK_RELEASE);
4076 done:
4077 callout_reset(&ipfw_timeout_h, dyn_keepalive_period * hz,
4078 ipfw_tick, NULL);
4079 }
4080
4081 /*
4082 * This procedure is only used to handle keepalives. It is invoked
4083 * every dyn_keepalive_period
4084 */
4085 static void
4086 ipfw_tick(void *dummy __unused)
4087 {
4088 struct lwkt_msg *lmsg = &ipfw_timeout_netmsg.nm_lmsg;
4089
4090 KKASSERT(mycpuid == IPFW_CFGCPUID);
4091
4092 crit_enter();
4093
4094 KKASSERT(lmsg->ms_flags & MSGF_DONE);
4095 if (IPFW_LOADED) {
4096 lwkt_sendmsg(IPFW_CFGPORT, lmsg);
4097 /* ipfw_timeout_netmsg's handler reset this callout */
4098 }
4099
4100 crit_exit();
4101 }
4102
4103 static int
4104 ipfw_check_in(void *arg, struct mbuf **m0, struct ifnet *ifp, int dir)
4105 {
4106 struct ip_fw_args args;
4107 struct mbuf *m = *m0;
4108 struct m_tag *mtag;
4109 int tee = 0, error = 0, ret;
4110
4111 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
4112 /* Extract info from dummynet tag */
4113 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
4114 KKASSERT(mtag != NULL);
4115 args.rule = ((struct dn_pkt *)m_tag_data(mtag))->dn_priv;
4116 KKASSERT(args.rule != NULL);
4117
4118 m_tag_delete(m, mtag);
4119 m->m_pkthdr.fw_flags &= ~DUMMYNET_MBUF_TAGGED;
4120 } else {
4121 args.rule = NULL;
4122 }
4123
4124 args.eh = NULL;
4125 args.oif = NULL;
4126 args.m = m;
4127 ret = ipfw_chk(&args);
4128 m = args.m;
4129
4130 if (m == NULL) {
4131 error = EACCES;
4132 goto back;
4133 }
4134
4135 switch (ret) {
4136 case IP_FW_PASS:
4137 break;
4138
4139 case IP_FW_DENY:
4140 m_freem(m);
4141 m = NULL;
4142 error = EACCES;
4143 break;
4144
4145 case IP_FW_DUMMYNET:
4146 /* Send packet to the appropriate pipe */
4147 ipfw_dummynet_io(m, args.cookie, DN_TO_IP_IN, &args);
4148 break;
4149
4150 case IP_FW_TEE:
4151 tee = 1;
4152 /* FALL THROUGH */
4153
4154 case IP_FW_DIVERT:
4155 if (ip_divert_p != NULL) {
4156 m = ip_divert_p(m, tee, 1);
4157 } else {
4158 m_freem(m);
4159 m = NULL;
4160 /* not sure this is the right error msg */
4161 error = EACCES;
4162 }
4163 break;
4164
4165 default:
4166 panic("unknown ipfw return value: %d\n", ret);
4167 }
4168 back:
4169 *m0 = m;
4170 return error;
4171 }
4172
4173 static int
4174 ipfw_check_out(void *arg, struct mbuf **m0, struct ifnet *ifp, int dir)
4175 {
4176 struct ip_fw_args args;
4177 struct mbuf *m = *m0;
4178 struct m_tag *mtag;
4179 int tee = 0, error = 0, ret;
4180
4181 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
4182 /* Extract info from dummynet tag */
4183 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
4184 KKASSERT(mtag != NULL);
4185 args.rule = ((struct dn_pkt *)m_tag_data(mtag))->dn_priv;
4186 KKASSERT(args.rule != NULL);
4187
4188 m_tag_delete(m, mtag);
4189 m->m_pkthdr.fw_flags &= ~DUMMYNET_MBUF_TAGGED;
4190 } else {
4191 args.rule = NULL;
4192 }
4193
4194 args.eh = NULL;
4195 args.m = m;
4196 args.oif = ifp;
4197 ret = ipfw_chk(&args);
4198 m = args.m;
4199
4200 if (m == NULL) {
4201 error = EACCES;
4202 goto back;
4203 }
4204
4205 switch (ret) {
4206 case IP_FW_PASS:
4207 break;
4208
4209 case IP_FW_DENY:
4210 m_freem(m);
4211 m = NULL;
4212 error = EACCES;
4213 break;
4214
4215 case IP_FW_DUMMYNET:
4216 ipfw_dummynet_io(m, args.cookie, DN_TO_IP_OUT, &args);
4217 break;
4218
4219 case IP_FW_TEE:
4220 tee = 1;
4221 /* FALL THROUGH */
4222
4223 case IP_FW_DIVERT:
4224 if (ip_divert_p != NULL) {
4225 m = ip_divert_p(m, tee, 0);
4226 } else {
4227 m_freem(m);
4228 m = NULL;
4229 /* not sure this is the right error msg */
4230 error = EACCES;
4231 }
4232 break;
4233
4234 default:
4235 panic("unknown ipfw return value: %d\n", ret);
4236 }
4237 back:
4238 *m0 = m;
4239 return error;
4240 }
4241
4242 static void
4243 ipfw_hook(void)
4244 {
4245 struct pfil_head *pfh;
4246
4247 IPFW_ASSERT_CFGPORT(&curthread->td_msgport);
4248
4249 pfh = pfil_head_get(PFIL_TYPE_AF, AF_INET);
4250 if (pfh == NULL)
4251 return;
4252
4253 pfil_add_hook(ipfw_check_in, NULL, PFIL_IN | PFIL_MPSAFE, pfh);
4254 pfil_add_hook(ipfw_check_out, NULL, PFIL_OUT | PFIL_MPSAFE, pfh);
4255 }
4256
4257 static void
4258 ipfw_dehook(void)
4259 {
4260 struct pfil_head *pfh;
4261
4262 IPFW_ASSERT_CFGPORT(&curthread->td_msgport);
4263
4264 pfh = pfil_head_get(PFIL_TYPE_AF, AF_INET);
4265 if (pfh == NULL)
4266 return;
4267
4268 pfil_remove_hook(ipfw_check_in, NULL, PFIL_IN, pfh);
4269 pfil_remove_hook(ipfw_check_out, NULL, PFIL_OUT, pfh);
4270 }
4271
4272 static void
4273 ipfw_sysctl_enable_dispatch(struct netmsg *nmsg)
4274 {
4275 struct lwkt_msg *lmsg = &nmsg->nm_lmsg;
4276 int enable = lmsg->u.ms_result;
4277
4278 if (fw_enable == enable)
4279 goto reply;
4280
4281 fw_enable = enable;
4282 if (fw_enable)
4283 ipfw_hook();
4284 else
4285 ipfw_dehook();
4286 reply:
4287 lwkt_replymsg(lmsg, 0);
4288 }
4289
4290 static int
4291 ipfw_sysctl_enable(SYSCTL_HANDLER_ARGS)
4292 {
4293 struct netmsg nmsg;
4294 struct lwkt_msg *lmsg;
4295 int enable, error;
4296
4297 enable = fw_enable;
4298 error = sysctl_handle_int(oidp, &enable, 0, req);
4299 if (error || req->newptr == NULL)
4300 return error;
4301
4302 netmsg_init(&nmsg, NULL, &curthread->td_msgport,
4303 0, ipfw_sysctl_enable_dispatch);
4304 lmsg = &nmsg.nm_lmsg;
4305 lmsg->u.ms_result = enable;
4306
4307 return lwkt_domsg(IPFW_CFGPORT, lmsg, 0);
4308 }
4309
4310 static int
4311 ipfw_sysctl_autoinc_step(SYSCTL_HANDLER_ARGS)
4312 {
4313 return sysctl_int_range(oidp, arg1, arg2, req,
4314 IPFW_AUTOINC_STEP_MIN, IPFW_AUTOINC_STEP_MAX);
4315 }
4316
4317 static int
4318 ipfw_sysctl_dyn_buckets(SYSCTL_HANDLER_ARGS)
4319 {
4320 int error, value;
4321
4322 lockmgr(&dyn_lock, LK_EXCLUSIVE);
4323
4324 value = dyn_buckets;
4325 error = sysctl_handle_int(oidp, &value, 0, req);
4326 if (error || !req->newptr)
4327 goto back;
4328
4329 /*
4330 * Make sure we have a power of 2 and
4331 * do not allow more than 64k entries.
4332 */
4333 error = EINVAL;
4334 if (value <= 1 || value > 65536)
4335 goto back;
4336 if ((value & (value - 1)) != 0)
4337 goto back;
4338
4339 error = 0;
4340 dyn_buckets = value;
4341 back:
4342 lockmgr(&dyn_lock, LK_RELEASE);
4343 return error;
4344 }
4345
4346 static int
4347 ipfw_sysctl_dyn_fin(SYSCTL_HANDLER_ARGS)
4348 {
4349 return sysctl_int_range(oidp, arg1, arg2, req,
4350 1, dyn_keepalive_period - 1);
4351 }
4352
4353 static int
4354 ipfw_sysctl_dyn_rst(SYSCTL_HANDLER_ARGS)
4355 {
4356 return sysctl_int_range(oidp, arg1, arg2, req,
4357 1, dyn_keepalive_period - 1);
4358 }
4359
4360 static void
4361 ipfw_ctx_init_dispatch(struct netmsg *nmsg)
4362 {
4363 struct netmsg_ipfw *fwmsg = (struct netmsg_ipfw *)nmsg;
4364 struct ipfw_context *ctx;
4365 struct ip_fw *def_rule;
4366
4367 ctx = kmalloc(sizeof(*ctx), M_IPFW, M_WAITOK | M_ZERO);
4368 ipfw_ctx[mycpuid] = ctx;
4369
4370 def_rule = kmalloc(sizeof(*def_rule), M_IPFW, M_WAITOK | M_ZERO);
4371
4372 def_rule->act_ofs = 0;
4373 def_rule->rulenum = IPFW_DEFAULT_RULE;
4374 def_rule->cmd_len = 1;
4375 def_rule->set = IPFW_DEFAULT_SET;
4376
4377 def_rule->cmd[0].len = 1;
4378 #ifdef IPFIREWALL_DEFAULT_TO_ACCEPT
4379 def_rule->cmd[0].opcode = O_ACCEPT;
4380 #else
4381 def_rule->cmd[0].opcode = O_DENY;
4382 #endif
4383
4384 def_rule->refcnt = 1;
4385 def_rule->cpuid = mycpuid;
4386
4387 /* Install the default rule */
4388 ctx->ipfw_default_rule = def_rule;
4389 ctx->ipfw_layer3_chain = def_rule;
4390
4391 /* Link rule CPU sibling */
4392 ipfw_link_sibling(fwmsg, def_rule);
4393
4394 /* Statistics only need to be updated once */
4395 if (mycpuid == 0)
4396 ipfw_inc_static_count(def_rule);
4397
4398 ifnet_forwardmsg(&nmsg->nm_lmsg, mycpuid + 1);
4399 }
4400
4401 static void
4402 ipfw_init_dispatch(struct netmsg *nmsg)
4403 {
4404 struct netmsg_ipfw fwmsg;
4405 int error = 0;
4406
4407 if (IPFW_LOADED) {
4408 kprintf("IP firewall already loaded\n");
4409 error = EEXIST;
4410 goto reply;
4411 }
4412
4413 bzero(&fwmsg, sizeof(fwmsg));
4414 netmsg_init(&fwmsg.nmsg, NULL, &curthread->td_msgport,
4415 0, ipfw_ctx_init_dispatch);
4416 ifnet_domsg(&fwmsg.nmsg.nm_lmsg, 0);
4417
4418 ip_fw_chk_ptr = ipfw_chk;
4419 ip_fw_ctl_ptr = ipfw_ctl;
4420 ip_fw_dn_io_ptr = ipfw_dummynet_io;
4421
4422 kprintf("ipfw2 initialized, default to %s, logging ",
4423 ipfw_ctx[mycpuid]->ipfw_default_rule->cmd[0].opcode ==
4424 O_ACCEPT ? "accept" : "deny");
4425
4426 #ifdef IPFIREWALL_VERBOSE
4427 fw_verbose = 1;
4428 #endif
4429 #ifdef IPFIREWALL_VERBOSE_LIMIT
4430 verbose_limit = IPFIREWALL_VERBOSE_LIMIT;
4431 #endif
4432 if (fw_verbose == 0) {
4433 kprintf("disabled\n");
4434 } else if (verbose_limit == 0) {
4435 kprintf("unlimited\n");
4436 } else {
4437 kprintf("limited to %d packets/entry by default\n",
4438 verbose_limit);
4439 }
4440
4441 callout_init_mp(&ipfw_timeout_h);
4442 netmsg_init(&ipfw_timeout_netmsg, NULL, &netisr_adone_rport,
4443 MSGF_MPSAFE | MSGF_DROPABLE | MSGF_PRIORITY,
4444 ipfw_tick_dispatch);
4445 lockinit(&dyn_lock, "ipfw_dyn", 0, 0);
4446
4447 ip_fw_loaded = 1;
4448 callout_reset(&ipfw_timeout_h, hz, ipfw_tick, NULL);
4449
4450 if (fw_enable)
4451 ipfw_hook();
4452 reply:
4453 lwkt_replymsg(&nmsg->nm_lmsg, error);
4454 }
4455
4456 static int
4457 ipfw_init(void)
4458 {
4459 struct netmsg smsg;
4460
4461 netmsg_init(&smsg, NULL, &curthread->td_msgport,
4462 0, ipfw_init_dispatch);
4463 return lwkt_domsg(IPFW_CFGPORT, &smsg.nm_lmsg, 0);
4464 }
4465
4466 #ifdef KLD_MODULE
4467
4468 static void
4469 ipfw_fini_dispatch(struct netmsg *nmsg)
4470 {
4471 int error = 0, cpu;
4472
4473 if (ipfw_refcnt != 0) {
4474 error = EBUSY;
4475 goto reply;
4476 }
4477
4478 ip_fw_loaded = 0;
4479
4480 ipfw_dehook();
4481 callout_stop(&ipfw_timeout_h);
4482
4483 netmsg_service_sync();
4484
4485 crit_enter();
4486 if ((ipfw_timeout_netmsg.nm_lmsg.ms_flags & MSGF_DONE) == 0) {
4487 /*
4488 * Callout message is pending; drop it
4489 */
4490 lwkt_dropmsg(&ipfw_timeout_netmsg.nm_lmsg);
4491 }
4492 crit_exit();
4493
4494 ip_fw_chk_ptr = NULL;
4495 ip_fw_ctl_ptr = NULL;
4496 ip_fw_dn_io_ptr = NULL;
4497 ipfw_flush(1 /* kill default rule */);
4498
4499 /* Free pre-cpu context */
4500 for (cpu = 0; cpu < ncpus; ++cpu)
4501 kfree(ipfw_ctx[cpu], M_IPFW);
4502
4503 kprintf("IP firewall unloaded\n");
4504 reply:
4505 lwkt_replymsg(&nmsg->nm_lmsg, error);
4506 }
4507
4508 static int
4509 ipfw_fini(void)
4510 {
4511 struct netmsg smsg;
4512
4513 netmsg_init(&smsg, NULL, &curthread->td_msgport,
4514 0, ipfw_fini_dispatch);
4515 return lwkt_domsg(IPFW_CFGPORT, &smsg.nm_lmsg, 0);
4516 }
4517
4518 #endif /* KLD_MODULE */
4519
4520 static int
4521 ipfw_modevent(module_t mod, int type, void *unused)
4522 {
4523 int err = 0;
4524
4525 switch (type) {
4526 case MOD_LOAD:
4527 err = ipfw_init();
4528 break;
4529
4530 case MOD_UNLOAD:
4531 #ifndef KLD_MODULE
4532 kprintf("ipfw statically compiled, cannot unload\n");
4533 err = EBUSY;
4534 #else
4535 err = ipfw_fini();
4536 #endif
4537 break;
4538 default:
4539 break;
4540 }
4541 return err;
4542 }
4543
4544 static moduledata_t ipfwmod = {
4545 "ipfw",
4546 ipfw_modevent,
4547 0
4548 };
4549 DECLARE_MODULE(ipfw, ipfwmod, SI_SUB_PROTO_END, SI_ORDER_ANY);
4550 MODULE_VERSION(ipfw, 1);
DragonFly BSD