1 /*-
2 * Copyright (c) 2002-2003 Luigi Rizzo
3 * Copyright (c) 1996 Alex Nash, Paul Traina, Poul-Henning Kamp
4 * Copyright (c) 1994 Ugen J.S.Antsilevich
5 *
6 * Idea and grammar partially left from:
7 * Copyright (c) 1993 Daniel Boulet
8 *
9 * Redistribution and use in source forms, with and without modification,
10 * are permitted provided that this entire comment appears intact.
11 *
12 * Redistribution in binary form may occur without any restrictions.
13 * Obviously, it would be nice if you gave credit where credit is due
14 * but requiring it would be too onerous.
15 *
16 * This software is provided ``AS IS'' without any warranties of any kind.
17 *
18 * NEW command line interface for IP firewall facility
19 *
20 * $FreeBSD$
21 *
22 * ipv6 support
23 */
24
25 #include <sys/types.h>
26 #include <sys/socket.h>
27
28 #include "ipfw2.h"
29
30 #include <err.h>
31 #include <netdb.h>
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <string.h>
35 #include <sysexits.h>
36
37 #include <net/if.h>
38 #include <netinet/in.h>
39 #include <netinet/in_systm.h>
40 #include <netinet/ip.h>
41 #include <netinet/icmp6.h>
42 #include <netinet/ip_fw.h>
43 #include <arpa/inet.h>
44
45 #define CHECK_LENGTH(v, len) do { \
46 if ((v) < (len)) \
47 errx(EX_DATAERR, "Rule too long"); \
48 } while (0)
49
50 static struct _s_x icmp6codes[] = {
51 { "no-route", ICMP6_DST_UNREACH_NOROUTE },
52 { "admin-prohib", ICMP6_DST_UNREACH_ADMIN },
53 { "address", ICMP6_DST_UNREACH_ADDR },
54 { "port", ICMP6_DST_UNREACH_NOPORT },
55 { NULL, 0 }
56 };
57
58 void
fill_unreach6_code(u_short * codep,char * str)59 fill_unreach6_code(u_short *codep, char *str)
60 {
61 int val;
62 char *s;
63
64 val = strtoul(str, &s, 0);
65 if (s == str || *s != '\0' || val >= 0x100)
66 val = match_token(icmp6codes, str);
67 if (val < 0)
68 errx(EX_DATAERR, "unknown ICMPv6 unreachable code ``%s''", str);
69 *codep = val;
70 return;
71 }
72
73 void
print_unreach6_code(struct buf_pr * bp,uint16_t code)74 print_unreach6_code(struct buf_pr *bp, uint16_t code)
75 {
76 char const *s = match_value(icmp6codes, code);
77
78 if (s != NULL)
79 bprintf(bp, "unreach6 %s", s);
80 else
81 bprintf(bp, "unreach6 %u", code);
82 }
83
84 /*
85 * Print the ip address contained in a command.
86 */
87 void
print_ip6(struct buf_pr * bp,ipfw_insn_ip6 * cmd)88 print_ip6(struct buf_pr *bp, ipfw_insn_ip6 *cmd)
89 {
90 char trad[255];
91 struct hostent *he = NULL;
92 struct in6_addr *a = &(cmd->addr6);
93 int len, mb;
94
95 len = F_LEN((ipfw_insn *) cmd) - 1;
96 if (cmd->o.opcode == O_IP6_SRC_ME || cmd->o.opcode == O_IP6_DST_ME) {
97 bprintf(bp, " me6");
98 return;
99 }
100 if (cmd->o.opcode == O_IP6) {
101 bprintf(bp, " ip6");
102 return;
103 }
104
105 /*
106 * len == 4 indicates a single IP, whereas lists of 1 or more
107 * addr/mask pairs have len = (2n+1). We convert len to n so we
108 * use that to count the number of entries.
109 */
110 bprintf(bp, " ");
111 for (len = len / 4; len > 0; len -= 2, a += 2) {
112 /* mask length */
113 mb = (cmd->o.opcode == O_IP6_SRC ||
114 cmd->o.opcode == O_IP6_DST) ? 128:
115 contigmask((uint8_t *)&(a[1]), 128);
116
117 if (mb == 128 && co.do_resolv)
118 he = gethostbyaddr((char *)a, sizeof(*a), AF_INET6);
119
120 if (he != NULL) /* resolved to name */
121 bprintf(bp, "%s", he->h_name);
122 else if (mb == 0) /* any */
123 bprintf(bp, "any");
124 else { /* numeric IP followed by some kind of mask */
125 if (inet_ntop(AF_INET6, a, trad,
126 sizeof(trad)) == NULL)
127 bprintf(bp, "Error ntop in print_ip6\n");
128 bprintf(bp, "%s", trad );
129 if (mb < 0) /* mask not contiguous */
130 bprintf(bp, "/%s", inet_ntop(AF_INET6, &a[1],
131 trad, sizeof(trad)));
132 else if (mb < 128)
133 bprintf(bp, "/%d", mb);
134 }
135 if (len > 2)
136 bprintf(bp, ",");
137 }
138 }
139
140 void
fill_icmp6types(ipfw_insn_icmp6 * cmd,char * av,int cblen)141 fill_icmp6types(ipfw_insn_icmp6 *cmd, char *av, int cblen)
142 {
143 uint8_t type;
144
145 CHECK_LENGTH(cblen, F_INSN_SIZE(ipfw_insn_icmp6));
146 while (*av) {
147 if (*av == ',')
148 av++;
149 type = strtoul(av, &av, 0);
150 if (*av != ',' && *av != '\0')
151 errx(EX_DATAERR, "invalid ICMP6 type");
152 /*
153 * XXX: shouldn't this be 0xFF? I can't see any reason why
154 * we shouldn't be able to filter all possiable values
155 * regardless of the ability of the rest of the kernel to do
156 * anything useful with them.
157 */
158 if (type > ICMP6_MAXTYPE)
159 errx(EX_DATAERR, "ICMP6 type out of range");
160 cmd->d[type / 32] |= ( 1 << (type % 32));
161 }
162 cmd->o.opcode = O_ICMP6TYPE;
163 cmd->o.len |= F_INSN_SIZE(ipfw_insn_icmp6);
164 }
165
166 void
print_icmp6types(struct buf_pr * bp,ipfw_insn_u32 * cmd)167 print_icmp6types(struct buf_pr *bp, ipfw_insn_u32 *cmd)
168 {
169 int i, j;
170 char sep= ' ';
171
172 bprintf(bp, " icmp6types");
173 for (i = 0; i < 7; i++)
174 for (j=0; j < 32; ++j) {
175 if ( (cmd->d[i] & (1 << (j))) == 0)
176 continue;
177 bprintf(bp, "%c%d", sep, (i*32 + j));
178 sep = ',';
179 }
180 }
181
182 void
print_flow6id(struct buf_pr * bp,ipfw_insn_u32 * cmd)183 print_flow6id(struct buf_pr *bp, ipfw_insn_u32 *cmd)
184 {
185 uint16_t i, limit = cmd->o.arg1;
186 char sep = ',';
187
188 bprintf(bp, " flow-id ");
189 for( i=0; i < limit; ++i) {
190 if (i == limit - 1)
191 sep = ' ';
192 bprintf(bp, "%d%c", cmd->d[i], sep);
193 }
194 }
195
196 /* structure and define for the extension header in ipv6 */
197 static struct _s_x ext6hdrcodes[] = {
198 { "frag", EXT_FRAGMENT },
199 { "hopopt", EXT_HOPOPTS },
200 { "route", EXT_ROUTING },
201 { "dstopt", EXT_DSTOPTS },
202 { "ah", EXT_AH },
203 { "esp", EXT_ESP },
204 { "rthdr0", EXT_RTHDR0 },
205 { "rthdr2", EXT_RTHDR2 },
206 { NULL, 0 }
207 };
208
209 /* fills command for the extension header filtering */
210 int
fill_ext6hdr(ipfw_insn * cmd,char * av)211 fill_ext6hdr( ipfw_insn *cmd, char *av)
212 {
213 int tok;
214 char *s = av;
215
216 cmd->arg1 = 0;
217 while(s) {
218 av = strsep( &s, ",") ;
219 tok = match_token(ext6hdrcodes, av);
220 switch (tok) {
221 case EXT_FRAGMENT:
222 cmd->arg1 |= EXT_FRAGMENT;
223 break;
224 case EXT_HOPOPTS:
225 cmd->arg1 |= EXT_HOPOPTS;
226 break;
227 case EXT_ROUTING:
228 cmd->arg1 |= EXT_ROUTING;
229 break;
230 case EXT_DSTOPTS:
231 cmd->arg1 |= EXT_DSTOPTS;
232 break;
233 case EXT_AH:
234 cmd->arg1 |= EXT_AH;
235 break;
236 case EXT_ESP:
237 cmd->arg1 |= EXT_ESP;
238 break;
239 case EXT_RTHDR0:
240 cmd->arg1 |= EXT_RTHDR0;
241 break;
242 case EXT_RTHDR2:
243 cmd->arg1 |= EXT_RTHDR2;
244 break;
245 default:
246 errx(EX_DATAERR,
247 "invalid option for ipv6 exten header");
248 break;
249 }
250 }
251 if (cmd->arg1 == 0)
252 return (0);
253 cmd->opcode = O_EXT_HDR;
254 cmd->len |= F_INSN_SIZE(ipfw_insn);
255 return (1);
256 }
257
258 void
print_ext6hdr(struct buf_pr * bp,ipfw_insn * cmd)259 print_ext6hdr(struct buf_pr *bp, ipfw_insn *cmd )
260 {
261 char sep = ' ';
262
263 bprintf(bp, " extension header:");
264 if (cmd->arg1 & EXT_FRAGMENT) {
265 bprintf(bp, "%cfragmentation", sep);
266 sep = ',';
267 }
268 if (cmd->arg1 & EXT_HOPOPTS) {
269 bprintf(bp, "%chop options", sep);
270 sep = ',';
271 }
272 if (cmd->arg1 & EXT_ROUTING) {
273 bprintf(bp, "%crouting options", sep);
274 sep = ',';
275 }
276 if (cmd->arg1 & EXT_RTHDR0) {
277 bprintf(bp, "%crthdr0", sep);
278 sep = ',';
279 }
280 if (cmd->arg1 & EXT_RTHDR2) {
281 bprintf(bp, "%crthdr2", sep);
282 sep = ',';
283 }
284 if (cmd->arg1 & EXT_DSTOPTS) {
285 bprintf(bp, "%cdestination options", sep);
286 sep = ',';
287 }
288 if (cmd->arg1 & EXT_AH) {
289 bprintf(bp, "%cauthentication header", sep);
290 sep = ',';
291 }
292 if (cmd->arg1 & EXT_ESP) {
293 bprintf(bp, "%cencapsulated security payload", sep);
294 }
295 }
296
297 /* Try to find ipv6 address by hostname */
298 static int
lookup_host6(char * host,struct in6_addr * ip6addr)299 lookup_host6 (char *host, struct in6_addr *ip6addr)
300 {
301 struct hostent *he;
302
303 if (!inet_pton(AF_INET6, host, ip6addr)) {
304 if ((he = gethostbyname2(host, AF_INET6)) == NULL)
305 return(-1);
306 memcpy(ip6addr, he->h_addr_list[0], sizeof( struct in6_addr));
307 }
308 return (0);
309 }
310
311
312 /*
313 * fill the addr and mask fields in the instruction as appropriate from av.
314 * Update length as appropriate.
315 * The following formats are allowed:
316 * any matches any IP6. Actually returns an empty instruction.
317 * me returns O_IP6_*_ME
318 *
319 * 03f1::234:123:0342 single IP6 address
320 * 03f1::234:123:0342/24 address/masklen
321 * 03f1::234:123:0342/ffff::ffff:ffff address/mask
322 * 03f1::234:123:0342/24,03f1::234:123:0343/ List of address
323 *
324 * Set of address (as in ipv6) not supported because ipv6 address
325 * are typically random past the initial prefix.
326 * Return 1 on success, 0 on failure.
327 */
328 static int
fill_ip6(ipfw_insn_ip6 * cmd,char * av,int cblen,struct tidx * tstate)329 fill_ip6(ipfw_insn_ip6 *cmd, char *av, int cblen, struct tidx *tstate)
330 {
331 int len = 0;
332 struct in6_addr *d = &(cmd->addr6);
333 char *oav;
334 /*
335 * Needed for multiple address.
336 * Note d[1] points to struct in6_add r mask6 of cmd
337 */
338
339 cmd->o.len &= ~F_LEN_MASK; /* zero len */
340
341 if (strcmp(av, "any") == 0)
342 return (1);
343
344
345 if (strcmp(av, "me") == 0) { /* Set the data for "me" opt*/
346 cmd->o.len |= F_INSN_SIZE(ipfw_insn);
347 return (1);
348 }
349
350 if (strcmp(av, "me6") == 0) { /* Set the data for "me" opt*/
351 cmd->o.len |= F_INSN_SIZE(ipfw_insn);
352 return (1);
353 }
354
355 if (strncmp(av, "table(", 6) == 0) {
356 fill_table(&cmd->o, av, O_IP_DST_LOOKUP, tstate);
357 return (1);
358 }
359
360 oav = av = strdup(av);
361 while (av) {
362 /*
363 * After the address we can have '/' indicating a mask,
364 * or ',' indicating another address follows.
365 */
366
367 char *p, *q;
368 int masklen;
369 char md = '\0';
370
371 CHECK_LENGTH(cblen, 1 + len + 2 * F_INSN_SIZE(struct in6_addr));
372
373 if ((q = strchr(av, ',')) ) {
374 *q = '\0';
375 q++;
376 }
377
378 if ((p = strchr(av, '/')) ) {
379 md = *p; /* save the separator */
380 *p = '\0'; /* terminate address string */
381 p++; /* and skip past it */
382 }
383 /* now p points to NULL, mask or next entry */
384
385 /* lookup stores address in *d as a side effect */
386 if (lookup_host6(av, d) != 0) {
387 /* XXX: failed. Free memory and go */
388 errx(EX_DATAERR, "bad address \"%s\"", av);
389 }
390 /* next, look at the mask, if any */
391 if (md == '/' && strchr(p, ':')) {
392 if (!inet_pton(AF_INET6, p, &d[1]))
393 errx(EX_DATAERR, "bad mask \"%s\"", p);
394
395 masklen = contigmask((uint8_t *)&(d[1]), 128);
396 } else {
397 masklen = (md == '/') ? atoi(p) : 128;
398 if (masklen > 128 || masklen < 0)
399 errx(EX_DATAERR, "bad width \"%s\''", p);
400 else
401 n2mask(&d[1], masklen);
402 }
403
404 APPLY_MASK(d, &d[1]); /* mask base address with mask */
405
406 av = q;
407
408 /* Check this entry */
409 if (masklen == 0) {
410 /*
411 * 'any' turns the entire list into a NOP.
412 * 'not any' never matches, so it is removed from the
413 * list unless it is the only item, in which case we
414 * report an error.
415 */
416 if (cmd->o.len & F_NOT && av == NULL && len == 0)
417 errx(EX_DATAERR, "not any never matches");
418 continue;
419 }
420
421 /*
422 * A single IP can be stored alone
423 */
424 if (masklen == 128 && av == NULL && len == 0) {
425 len = F_INSN_SIZE(struct in6_addr);
426 break;
427 }
428
429 /* Update length and pointer to arguments */
430 len += F_INSN_SIZE(struct in6_addr)*2;
431 d += 2;
432 } /* end while */
433
434 /*
435 * Total length of the command, remember that 1 is the size of
436 * the base command.
437 */
438 if (len + 1 > F_LEN_MASK)
439 errx(EX_DATAERR, "address list too long");
440 cmd->o.len |= len+1;
441 free(oav);
442 return (1);
443 }
444
445 /*
446 * fills command for ipv6 flow-id filtering
447 * note that the 20 bit flow number is stored in a array of u_int32_t
448 * it's supported lists of flow-id, so in the o.arg1 we store how many
449 * additional flow-id we want to filter, the basic is 1
450 */
451 void
fill_flow6(ipfw_insn_u32 * cmd,char * av,int cblen)452 fill_flow6( ipfw_insn_u32 *cmd, char *av, int cblen)
453 {
454 u_int32_t type; /* Current flow number */
455 u_int16_t nflow = 0; /* Current flow index */
456 char *s = av;
457 cmd->d[0] = 0; /* Initializing the base number*/
458
459 while (s) {
460 CHECK_LENGTH(cblen, F_INSN_SIZE(ipfw_insn_u32) + nflow + 1);
461
462 av = strsep( &s, ",") ;
463 type = strtoul(av, &av, 0);
464 if (*av != ',' && *av != '\0')
465 errx(EX_DATAERR, "invalid ipv6 flow number %s", av);
466 if (type > 0xfffff)
467 errx(EX_DATAERR, "flow number out of range %s", av);
468 cmd->d[nflow] |= type;
469 nflow++;
470 }
471 if( nflow > 0 ) {
472 cmd->o.opcode = O_FLOW6ID;
473 cmd->o.len |= F_INSN_SIZE(ipfw_insn_u32) + nflow;
474 cmd->o.arg1 = nflow;
475 }
476 else {
477 errx(EX_DATAERR, "invalid ipv6 flow number %s", av);
478 }
479 }
480
481 ipfw_insn *
add_srcip6(ipfw_insn * cmd,char * av,int cblen,struct tidx * tstate)482 add_srcip6(ipfw_insn *cmd, char *av, int cblen, struct tidx *tstate)
483 {
484
485 fill_ip6((ipfw_insn_ip6 *)cmd, av, cblen, tstate);
486 if (cmd->opcode == O_IP_DST_SET) /* set */
487 cmd->opcode = O_IP_SRC_SET;
488 else if (cmd->opcode == O_IP_DST_LOOKUP) /* table */
489 cmd->opcode = O_IP_SRC_LOOKUP;
490 else if (F_LEN(cmd) == 0) { /* any */
491 } else if (F_LEN(cmd) == F_INSN_SIZE(ipfw_insn)) { /* "me" */
492 cmd->opcode = O_IP6_SRC_ME;
493 } else if (F_LEN(cmd) ==
494 (F_INSN_SIZE(struct in6_addr) + F_INSN_SIZE(ipfw_insn))) {
495 /* single IP, no mask*/
496 cmd->opcode = O_IP6_SRC;
497 } else { /* addr/mask opt */
498 cmd->opcode = O_IP6_SRC_MASK;
499 }
500 return cmd;
501 }
502
503 ipfw_insn *
add_dstip6(ipfw_insn * cmd,char * av,int cblen,struct tidx * tstate)504 add_dstip6(ipfw_insn *cmd, char *av, int cblen, struct tidx *tstate)
505 {
506
507 fill_ip6((ipfw_insn_ip6 *)cmd, av, cblen, tstate);
508 if (cmd->opcode == O_IP_DST_SET) /* set */
509 ;
510 else if (cmd->opcode == O_IP_DST_LOOKUP) /* table */
511 ;
512 else if (F_LEN(cmd) == 0) { /* any */
513 } else if (F_LEN(cmd) == F_INSN_SIZE(ipfw_insn)) { /* "me" */
514 cmd->opcode = O_IP6_DST_ME;
515 } else if (F_LEN(cmd) ==
516 (F_INSN_SIZE(struct in6_addr) + F_INSN_SIZE(ipfw_insn))) {
517 /* single IP, no mask*/
518 cmd->opcode = O_IP6_DST;
519 } else { /* addr/mask opt */
520 cmd->opcode = O_IP6_DST_MASK;
521 }
522 return cmd;
523 }
524