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 memset(cmd, 0, sizeof(*cmd));
147 while (*av) {
148 if (*av == ',')
149 av++;
150 type = strtoul(av, &av, 0);
151 if (*av != ',' && *av != '\0')
152 errx(EX_DATAERR, "invalid ICMP6 type");
153 /*
154 * XXX: shouldn't this be 0xFF? I can't see any reason why
155 * we shouldn't be able to filter all possiable values
156 * regardless of the ability of the rest of the kernel to do
157 * anything useful with them.
158 */
159 if (type > ICMP6_MAXTYPE)
160 errx(EX_DATAERR, "ICMP6 type out of range");
161 cmd->d[type / 32] |= ( 1 << (type % 32));
162 }
163 cmd->o.opcode = O_ICMP6TYPE;
164 cmd->o.len |= F_INSN_SIZE(ipfw_insn_icmp6);
165 }
166
167 void
print_icmp6types(struct buf_pr * bp,ipfw_insn_u32 * cmd)168 print_icmp6types(struct buf_pr *bp, ipfw_insn_u32 *cmd)
169 {
170 int i, j;
171 char sep= ' ';
172
173 bprintf(bp, " icmp6types");
174 for (i = 0; i < 7; i++)
175 for (j=0; j < 32; ++j) {
176 if ( (cmd->d[i] & (1 << (j))) == 0)
177 continue;
178 bprintf(bp, "%c%d", sep, (i*32 + j));
179 sep = ',';
180 }
181 }
182
183 void
print_flow6id(struct buf_pr * bp,ipfw_insn_u32 * cmd)184 print_flow6id(struct buf_pr *bp, ipfw_insn_u32 *cmd)
185 {
186 uint16_t i, limit = cmd->o.arg1;
187 char sep = ',';
188
189 bprintf(bp, " flow-id ");
190 for( i=0; i < limit; ++i) {
191 if (i == limit - 1)
192 sep = ' ';
193 bprintf(bp, "%d%c", cmd->d[i], sep);
194 }
195 }
196
197 /* structure and define for the extension header in ipv6 */
198 static struct _s_x ext6hdrcodes[] = {
199 { "frag", EXT_FRAGMENT },
200 { "hopopt", EXT_HOPOPTS },
201 { "route", EXT_ROUTING },
202 { "dstopt", EXT_DSTOPTS },
203 { "ah", EXT_AH },
204 { "esp", EXT_ESP },
205 { "rthdr0", EXT_RTHDR0 },
206 { "rthdr2", EXT_RTHDR2 },
207 { NULL, 0 }
208 };
209
210 /* fills command for the extension header filtering */
211 int
fill_ext6hdr(ipfw_insn * cmd,char * av)212 fill_ext6hdr( ipfw_insn *cmd, char *av)
213 {
214 int tok;
215 char *s = av;
216
217 cmd->arg1 = 0;
218 while(s) {
219 av = strsep( &s, ",") ;
220 tok = match_token(ext6hdrcodes, av);
221 switch (tok) {
222 case EXT_FRAGMENT:
223 cmd->arg1 |= EXT_FRAGMENT;
224 break;
225 case EXT_HOPOPTS:
226 cmd->arg1 |= EXT_HOPOPTS;
227 break;
228 case EXT_ROUTING:
229 cmd->arg1 |= EXT_ROUTING;
230 break;
231 case EXT_DSTOPTS:
232 cmd->arg1 |= EXT_DSTOPTS;
233 break;
234 case EXT_AH:
235 cmd->arg1 |= EXT_AH;
236 break;
237 case EXT_ESP:
238 cmd->arg1 |= EXT_ESP;
239 break;
240 case EXT_RTHDR0:
241 cmd->arg1 |= EXT_RTHDR0;
242 break;
243 case EXT_RTHDR2:
244 cmd->arg1 |= EXT_RTHDR2;
245 break;
246 default:
247 errx(EX_DATAERR,
248 "invalid option for ipv6 exten header");
249 break;
250 }
251 }
252 if (cmd->arg1 == 0)
253 return (0);
254 cmd->opcode = O_EXT_HDR;
255 cmd->len |= F_INSN_SIZE(ipfw_insn);
256 return (1);
257 }
258
259 void
print_ext6hdr(struct buf_pr * bp,ipfw_insn * cmd)260 print_ext6hdr(struct buf_pr *bp, ipfw_insn *cmd )
261 {
262 char sep = ' ';
263
264 bprintf(bp, " extension header:");
265 if (cmd->arg1 & EXT_FRAGMENT) {
266 bprintf(bp, "%cfragmentation", sep);
267 sep = ',';
268 }
269 if (cmd->arg1 & EXT_HOPOPTS) {
270 bprintf(bp, "%chop options", sep);
271 sep = ',';
272 }
273 if (cmd->arg1 & EXT_ROUTING) {
274 bprintf(bp, "%crouting options", sep);
275 sep = ',';
276 }
277 if (cmd->arg1 & EXT_RTHDR0) {
278 bprintf(bp, "%crthdr0", sep);
279 sep = ',';
280 }
281 if (cmd->arg1 & EXT_RTHDR2) {
282 bprintf(bp, "%crthdr2", sep);
283 sep = ',';
284 }
285 if (cmd->arg1 & EXT_DSTOPTS) {
286 bprintf(bp, "%cdestination options", sep);
287 sep = ',';
288 }
289 if (cmd->arg1 & EXT_AH) {
290 bprintf(bp, "%cauthentication header", sep);
291 sep = ',';
292 }
293 if (cmd->arg1 & EXT_ESP) {
294 bprintf(bp, "%cencapsulated security payload", sep);
295 }
296 }
297
298 /* Try to find ipv6 address by hostname */
299 static int
lookup_host6(char * host,struct in6_addr * ip6addr)300 lookup_host6 (char *host, struct in6_addr *ip6addr)
301 {
302 struct hostent *he;
303
304 if (!inet_pton(AF_INET6, host, ip6addr)) {
305 if ((he = gethostbyname2(host, AF_INET6)) == NULL)
306 return(-1);
307 memcpy(ip6addr, he->h_addr_list[0], sizeof( struct in6_addr));
308 }
309 return (0);
310 }
311
312
313 /*
314 * fill the addr and mask fields in the instruction as appropriate from av.
315 * Update length as appropriate.
316 * The following formats are allowed:
317 * any matches any IP6. Actually returns an empty instruction.
318 * me returns O_IP6_*_ME
319 *
320 * 03f1::234:123:0342 single IP6 address
321 * 03f1::234:123:0342/24 address/masklen
322 * 03f1::234:123:0342/ffff::ffff:ffff address/mask
323 * 03f1::234:123:0342/24,03f1::234:123:0343/ List of address
324 *
325 * Set of address (as in ipv6) not supported because ipv6 address
326 * are typically random past the initial prefix.
327 * Return 1 on success, 0 on failure.
328 */
329 static int
fill_ip6(ipfw_insn_ip6 * cmd,char * av,int cblen,struct tidx * tstate)330 fill_ip6(ipfw_insn_ip6 *cmd, char *av, int cblen, struct tidx *tstate)
331 {
332 int len = 0;
333 struct in6_addr *d = &(cmd->addr6);
334 char *oav;
335 /*
336 * Needed for multiple address.
337 * Note d[1] points to struct in6_add r mask6 of cmd
338 */
339
340 cmd->o.len &= ~F_LEN_MASK; /* zero len */
341
342 if (strcmp(av, "any") == 0)
343 return (1);
344
345
346 if (strcmp(av, "me") == 0) { /* Set the data for "me" opt*/
347 cmd->o.len |= F_INSN_SIZE(ipfw_insn);
348 return (1);
349 }
350
351 if (strcmp(av, "me6") == 0) { /* Set the data for "me" opt*/
352 cmd->o.len |= F_INSN_SIZE(ipfw_insn);
353 return (1);
354 }
355
356 if (strncmp(av, "table(", 6) == 0) {
357 fill_table(&cmd->o, av, O_IP_DST_LOOKUP, tstate);
358 return (1);
359 }
360
361 oav = av = strdup(av);
362 while (av) {
363 /*
364 * After the address we can have '/' indicating a mask,
365 * or ',' indicating another address follows.
366 */
367
368 char *p, *q;
369 int masklen;
370 char md = '\0';
371
372 CHECK_LENGTH(cblen, 1 + len + 2 * F_INSN_SIZE(struct in6_addr));
373
374 if ((q = strchr(av, ',')) ) {
375 *q = '\0';
376 q++;
377 }
378
379 if ((p = strchr(av, '/')) ) {
380 md = *p; /* save the separator */
381 *p = '\0'; /* terminate address string */
382 p++; /* and skip past it */
383 }
384 /* now p points to NULL, mask or next entry */
385
386 /* lookup stores address in *d as a side effect */
387 if (lookup_host6(av, d) != 0) {
388 /* XXX: failed. Free memory and go */
389 errx(EX_DATAERR, "bad address \"%s\"", av);
390 }
391 /* next, look at the mask, if any */
392 if (md == '/' && strchr(p, ':')) {
393 if (!inet_pton(AF_INET6, p, &d[1]))
394 errx(EX_DATAERR, "bad mask \"%s\"", p);
395
396 masklen = contigmask((uint8_t *)&(d[1]), 128);
397 } else {
398 masklen = (md == '/') ? atoi(p) : 128;
399 if (masklen > 128 || masklen < 0)
400 errx(EX_DATAERR, "bad width \"%s\''", p);
401 else
402 n2mask(&d[1], masklen);
403 }
404
405 APPLY_MASK(d, &d[1]); /* mask base address with mask */
406
407 av = q;
408
409 /* Check this entry */
410 if (masklen == 0) {
411 /*
412 * 'any' turns the entire list into a NOP.
413 * 'not any' never matches, so it is removed from the
414 * list unless it is the only item, in which case we
415 * report an error.
416 */
417 if (cmd->o.len & F_NOT && av == NULL && len == 0)
418 errx(EX_DATAERR, "not any never matches");
419 continue;
420 }
421
422 /*
423 * A single IP can be stored alone
424 */
425 if (masklen == 128 && av == NULL && len == 0) {
426 len = F_INSN_SIZE(struct in6_addr);
427 break;
428 }
429
430 /* Update length and pointer to arguments */
431 len += F_INSN_SIZE(struct in6_addr)*2;
432 d += 2;
433 } /* end while */
434
435 /*
436 * Total length of the command, remember that 1 is the size of
437 * the base command.
438 */
439 if (len + 1 > F_LEN_MASK)
440 errx(EX_DATAERR, "address list too long");
441 cmd->o.len |= len+1;
442 free(oav);
443 return (1);
444 }
445
446 /*
447 * fills command for ipv6 flow-id filtering
448 * note that the 20 bit flow number is stored in a array of u_int32_t
449 * it's supported lists of flow-id, so in the o.arg1 we store how many
450 * additional flow-id we want to filter, the basic is 1
451 */
452 void
fill_flow6(ipfw_insn_u32 * cmd,char * av,int cblen)453 fill_flow6( ipfw_insn_u32 *cmd, char *av, int cblen)
454 {
455 u_int32_t type; /* Current flow number */
456 u_int16_t nflow = 0; /* Current flow index */
457 char *s = av;
458 cmd->d[0] = 0; /* Initializing the base number*/
459
460 while (s) {
461 CHECK_LENGTH(cblen, F_INSN_SIZE(ipfw_insn_u32) + nflow + 1);
462
463 av = strsep( &s, ",") ;
464 type = strtoul(av, &av, 0);
465 if (*av != ',' && *av != '\0')
466 errx(EX_DATAERR, "invalid ipv6 flow number %s", av);
467 if (type > 0xfffff)
468 errx(EX_DATAERR, "flow number out of range %s", av);
469 cmd->d[nflow] |= type;
470 nflow++;
471 }
472 if( nflow > 0 ) {
473 cmd->o.opcode = O_FLOW6ID;
474 cmd->o.len |= F_INSN_SIZE(ipfw_insn_u32) + nflow;
475 cmd->o.arg1 = nflow;
476 }
477 else {
478 errx(EX_DATAERR, "invalid ipv6 flow number %s", av);
479 }
480 }
481
482 ipfw_insn *
add_srcip6(ipfw_insn * cmd,char * av,int cblen,struct tidx * tstate)483 add_srcip6(ipfw_insn *cmd, char *av, int cblen, struct tidx *tstate)
484 {
485
486 fill_ip6((ipfw_insn_ip6 *)cmd, av, cblen, tstate);
487 if (cmd->opcode == O_IP_DST_SET) /* set */
488 cmd->opcode = O_IP_SRC_SET;
489 else if (cmd->opcode == O_IP_DST_LOOKUP) /* table */
490 cmd->opcode = O_IP_SRC_LOOKUP;
491 else if (F_LEN(cmd) == 0) { /* any */
492 } else if (F_LEN(cmd) == F_INSN_SIZE(ipfw_insn)) { /* "me" */
493 cmd->opcode = O_IP6_SRC_ME;
494 } else if (F_LEN(cmd) ==
495 (F_INSN_SIZE(struct in6_addr) + F_INSN_SIZE(ipfw_insn))) {
496 /* single IP, no mask*/
497 cmd->opcode = O_IP6_SRC;
498 } else { /* addr/mask opt */
499 cmd->opcode = O_IP6_SRC_MASK;
500 }
501 return cmd;
502 }
503
504 ipfw_insn *
add_dstip6(ipfw_insn * cmd,char * av,int cblen,struct tidx * tstate)505 add_dstip6(ipfw_insn *cmd, char *av, int cblen, struct tidx *tstate)
506 {
507
508 fill_ip6((ipfw_insn_ip6 *)cmd, av, cblen, tstate);
509 if (cmd->opcode == O_IP_DST_SET) /* set */
510 ;
511 else if (cmd->opcode == O_IP_DST_LOOKUP) /* table */
512 ;
513 else if (F_LEN(cmd) == 0) { /* any */
514 } else if (F_LEN(cmd) == F_INSN_SIZE(ipfw_insn)) { /* "me" */
515 cmd->opcode = O_IP6_DST_ME;
516 } else if (F_LEN(cmd) ==
517 (F_INSN_SIZE(struct in6_addr) + F_INSN_SIZE(ipfw_insn))) {
518 /* single IP, no mask*/
519 cmd->opcode = O_IP6_DST;
520 } else { /* addr/mask opt */
521 cmd->opcode = O_IP6_DST_MASK;
522 }
523 return cmd;
524 }
525