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 * ipv6 support
21 */
22
23#include <sys/types.h>
24#include <sys/socket.h>
25
26#include "ipfw2.h"
27
28#include <err.h>
29#include <netdb.h>
30#include <stdio.h>
31#include <stdlib.h>
32#include <string.h>
33#include <sysexits.h>
34
35#include <net/if.h>
36#include <netinet/in.h>
37#include <netinet/in_systm.h>
38#include <netinet/ip.h>
39#include <netinet/icmp6.h>
40#include <netinet/ip_fw.h>
41#include <arpa/inet.h>
42
43#define	CHECK_LENGTH(v, len) do {			\
44	if ((v) < (len))				\
45		errx(EX_DATAERR, "Rule too long");	\
46	} while (0)
47
48static struct _s_x icmp6codes[] = {
49	{ "no-route",		ICMP6_DST_UNREACH_NOROUTE },
50	{ "admin-prohib",		ICMP6_DST_UNREACH_ADMIN },
51	{ "address",		ICMP6_DST_UNREACH_ADDR },
52	{ "port",			ICMP6_DST_UNREACH_NOPORT },
53	{ NULL, 0 }
54};
55
56uint16_t
57get_unreach6_code(const char *str)
58{
59	int val;
60	char *s;
61
62	val = strtoul(str, &s, 0);
63	if (s == str || *s != '\0' || val >= 0x100)
64		val = match_token(icmp6codes, str);
65	if (val < 0)
66		errx(EX_DATAERR, "unknown ICMPv6 unreachable code ``%s''", str);
67	return (val);
68}
69
70void
71print_unreach6_code(struct buf_pr *bp, uint16_t code)
72{
73	char const *s = match_value(icmp6codes, code);
74
75	if (s != NULL)
76		bprintf(bp, "unreach6 %s", s);
77	else
78		bprintf(bp, "unreach6 %u", code);
79}
80
81/*
82 * Print the ip address contained in a command.
83 */
84void
85print_ip6(struct buf_pr *bp, const ipfw_insn_ip6 *cmd)
86{
87	char trad[255];
88	struct hostent *he = NULL;
89	const struct in6_addr *a = &(cmd->addr6);
90	int len, mb;
91
92	len = F_LEN((const ipfw_insn *)cmd) - 1;
93	if (cmd->o.opcode == O_IP6_SRC_ME || cmd->o.opcode == O_IP6_DST_ME) {
94		bprintf(bp, " me6");
95		return;
96	}
97	if (cmd->o.opcode == O_IP6) {
98		bprintf(bp, " ip6");
99		return;
100	}
101
102	/*
103	 * len == 4 indicates a single IP, whereas lists of 1 or more
104	 * addr/mask pairs have len = (2n+1). We convert len to n so we
105	 * use that to count the number of entries.
106	 */
107	bprintf(bp, " ");
108	for (len = len / 4; len > 0; len -= 2, a += 2) {
109		/* mask length */
110		mb = (cmd->o.opcode == O_IP6_SRC ||
111		    cmd->o.opcode == O_IP6_DST) ?  128:
112		    contigmask((const uint8_t *)&(a[1]), 128);
113
114		if (mb == 128 && g_co.do_resolv)
115			he = gethostbyaddr((const char *)a, sizeof(*a),
116			    AF_INET6);
117
118		if (he != NULL)	     /* resolved to name */
119			bprintf(bp, "%s", he->h_name);
120		else if (mb == 0)	   /* any */
121			bprintf(bp, "any");
122		else {	  /* numeric IP followed by some kind of mask */
123			if (inet_ntop(AF_INET6,  a, trad,
124			    sizeof(trad)) == NULL)
125				bprintf(bp, "Error ntop in print_ip6\n");
126			bprintf(bp, "%s",  trad );
127			if (mb < 0) /* mask not contiguous */
128				bprintf(bp, "/%s", inet_ntop(AF_INET6, &a[1],
129				    trad, sizeof(trad)));
130			else if (mb < 128)
131				bprintf(bp, "/%d", mb);
132		}
133		if (len > 2)
134			bprintf(bp, ",");
135	}
136}
137
138void
139fill_icmp6types(ipfw_insn_icmp6 *cmd, char *av, int cblen)
140{
141       uint8_t type;
142
143       CHECK_LENGTH(cblen, (int)F_INSN_SIZE(ipfw_insn_icmp6));
144       memset(cmd, 0, sizeof(*cmd));
145       while (*av) {
146	       if (*av == ',')
147		       av++;
148	       type = strtoul(av, &av, 0);
149	       if (*av != ',' && *av != '\0')
150		       errx(EX_DATAERR, "invalid ICMP6 type");
151	       /*
152		* XXX: shouldn't this be 0xFF?  I can't see any reason why
153		* we shouldn't be able to filter all possiable values
154		* regardless of the ability of the rest of the kernel to do
155		* anything useful with them.
156		*/
157	       if (type > ICMP6_MAXTYPE)
158		       errx(EX_DATAERR, "ICMP6 type out of range");
159	       cmd->d[type / 32] |= ( 1 << (type % 32));
160       }
161       cmd->o.opcode = O_ICMP6TYPE;
162       cmd->o.len |= F_INSN_SIZE(ipfw_insn_icmp6);
163}
164
165void
166print_icmp6types(struct buf_pr *bp, const ipfw_insn_u32 *cmd)
167{
168	int i, j;
169	char sep= ' ';
170
171	bprintf(bp, " icmp6types");
172	for (i = 0; i < 7; i++)
173		for (j=0; j < 32; ++j) {
174			if ( (cmd->d[i] & (1 << (j))) == 0)
175				continue;
176			bprintf(bp, "%c%d", sep, (i*32 + j));
177			sep = ',';
178		}
179}
180
181void
182print_flow6id(struct buf_pr *bp, const ipfw_insn_u32 *cmd)
183{
184	uint16_t i, limit = cmd->o.arg1;
185	char sep = ',';
186
187	bprintf(bp, " flow-id ");
188	for( i=0; i < limit; ++i) {
189		if (i == limit - 1)
190			sep = ' ';
191		bprintf(bp, "%d%c", cmd->d[i], sep);
192	}
193}
194
195/* structure and define for the extension header in ipv6 */
196static struct _s_x ext6hdrcodes[] = {
197	{ "frag",       EXT_FRAGMENT },
198	{ "hopopt",     EXT_HOPOPTS },
199	{ "route",      EXT_ROUTING },
200	{ "dstopt",     EXT_DSTOPTS },
201	{ "ah",	 EXT_AH },
202	{ "esp",	EXT_ESP },
203	{ "rthdr0",     EXT_RTHDR0 },
204	{ "rthdr2",     EXT_RTHDR2 },
205	{ NULL,	 0 }
206};
207
208/* fills command for the extension header filtering */
209int
210fill_ext6hdr( ipfw_insn *cmd, char *av)
211{
212	int tok;
213	char *s = av;
214
215	cmd->arg1 = 0;
216	while(s) {
217		av = strsep( &s, ",") ;
218		tok = match_token(ext6hdrcodes, av);
219		switch (tok) {
220		case EXT_FRAGMENT:
221			cmd->arg1 |= EXT_FRAGMENT;
222			break;
223		case EXT_HOPOPTS:
224			cmd->arg1 |= EXT_HOPOPTS;
225			break;
226		case EXT_ROUTING:
227			cmd->arg1 |= EXT_ROUTING;
228			break;
229		case EXT_DSTOPTS:
230			cmd->arg1 |= EXT_DSTOPTS;
231			break;
232		case EXT_AH:
233			cmd->arg1 |= EXT_AH;
234			break;
235		case EXT_ESP:
236			cmd->arg1 |= EXT_ESP;
237			break;
238		case EXT_RTHDR0:
239			cmd->arg1 |= EXT_RTHDR0;
240			break;
241		case EXT_RTHDR2:
242			cmd->arg1 |= EXT_RTHDR2;
243			break;
244		default:
245			errx(EX_DATAERR,
246			    "invalid option for ipv6 exten header");
247			break;
248		}
249	}
250	if (cmd->arg1 == 0)
251		return (0);
252	cmd->opcode = O_EXT_HDR;
253	cmd->len |= F_INSN_SIZE(ipfw_insn);
254	return (1);
255}
256
257void
258print_ext6hdr(struct buf_pr *bp, const ipfw_insn *cmd )
259{
260	char sep = ' ';
261
262	bprintf(bp, " extension header:");
263	if (cmd->arg1 & EXT_FRAGMENT) {
264		bprintf(bp, "%cfragmentation", sep);
265		sep = ',';
266	}
267	if (cmd->arg1 & EXT_HOPOPTS) {
268		bprintf(bp, "%chop options", sep);
269		sep = ',';
270	}
271	if (cmd->arg1 & EXT_ROUTING) {
272		bprintf(bp, "%crouting options", sep);
273		sep = ',';
274	}
275	if (cmd->arg1 & EXT_RTHDR0) {
276		bprintf(bp, "%crthdr0", sep);
277		sep = ',';
278	}
279	if (cmd->arg1 & EXT_RTHDR2) {
280		bprintf(bp, "%crthdr2", sep);
281		sep = ',';
282	}
283	if (cmd->arg1 & EXT_DSTOPTS) {
284		bprintf(bp, "%cdestination options", sep);
285		sep = ',';
286	}
287	if (cmd->arg1 & EXT_AH) {
288		bprintf(bp, "%cauthentication header", sep);
289		sep = ',';
290	}
291	if (cmd->arg1 & EXT_ESP) {
292		bprintf(bp, "%cencapsulated security payload", sep);
293	}
294}
295
296/* Try to find ipv6 address by hostname */
297static int
298lookup_host6 (char *host, struct in6_addr *ip6addr)
299{
300	struct hostent *he;
301
302	if (!inet_pton(AF_INET6, host, ip6addr)) {
303		if ((he = gethostbyname2(host, AF_INET6)) == NULL)
304			return(-1);
305		memcpy(ip6addr, he->h_addr_list[0], sizeof( struct in6_addr));
306	}
307	return (0);
308}
309
310
311/*
312 * fill the addr and mask fields in the instruction as appropriate from av.
313 * Update length as appropriate.
314 * The following formats are allowed:
315 *     any     matches any IP6. Actually returns an empty instruction.
316 *     me      returns O_IP6_*_ME
317 *
318 *     03f1::234:123:0342			single IP6 address
319 *     03f1::234:123:0342/24			address/masklen
320 *     03f1::234:123:0342/ffff::ffff:ffff	address/mask
321 *     03f1::234:123:0342/24,03f1::234:123:0343/	List of address
322 *
323 * Set of address (as in ipv6) not supported because ipv6 address
324 * are typically random past the initial prefix.
325 * Return 1 on success, 0 on failure.
326 */
327static int
328fill_ip6(ipfw_insn_ip6 *cmd, char *av, int cblen, struct tidx *tstate)
329{
330	int len = 0;
331	struct in6_addr *d = &(cmd->addr6);
332	char *oav;
333	/*
334	 * Needed for multiple address.
335	 * Note d[1] points to struct in6_add r mask6 of cmd
336	 */
337
338	cmd->o.len &= ~F_LEN_MASK;	/* zero len */
339
340	if (strcmp(av, "any") == 0)
341		return (1);
342
343	/* Set the data for "me" opt */
344	if (strcmp(av, "me") == 0 || strcmp(av, "me6") == 0) {
345		cmd->o.len |= F_INSN_SIZE(ipfw_insn);
346		return (1);
347	}
348
349	if (strncmp(av, "table(", 6) == 0) {
350		fill_table(&cmd->o, av, O_IP_DST_LOOKUP, tstate);
351		return (1);
352	}
353
354	oav = av = strdup(av);
355	while (av) {
356		/*
357		 * After the address we can have '/' indicating a mask,
358		 * or ',' indicating another address follows.
359		 */
360
361		char *p, *q;
362		int masklen;
363		char md = '\0';
364
365		CHECK_LENGTH(cblen,
366		    1 + len + 2 * (int)F_INSN_SIZE(struct in6_addr));
367
368		if ((q = strchr(av, ',')) ) {
369			*q = '\0';
370			q++;
371		}
372
373		if ((p = strchr(av, '/')) ) {
374			md = *p;	/* save the separator */
375			*p = '\0';	/* terminate address string */
376			p++;		/* and skip past it */
377		}
378		/* now p points to NULL, mask or next entry */
379
380		/* lookup stores address in *d as a side effect */
381		if (lookup_host6(av, d) != 0) {
382			/* XXX: failed. Free memory and go */
383			errx(EX_DATAERR, "bad address \"%s\"", av);
384		}
385		/* next, look at the mask, if any */
386		if (md == '/' && strchr(p, ':')) {
387			if (!inet_pton(AF_INET6, p, &d[1]))
388				errx(EX_DATAERR, "bad mask \"%s\"", p);
389
390			masklen = contigmask((uint8_t *)&(d[1]), 128);
391		} else {
392			masklen = (md == '/') ? atoi(p) : 128;
393			if (masklen > 128 || masklen < 0)
394				errx(EX_DATAERR, "bad width \"%s\''", p);
395			else
396				n2mask(&d[1], masklen);
397		}
398
399		APPLY_MASK(d, &d[1]);   /* mask base address with mask */
400
401		av = q;
402
403		/* Check this entry */
404		if (masklen == 0) {
405			/*
406			 * 'any' turns the entire list into a NOP.
407			 * 'not any' never matches, so it is removed from the
408			 * list unless it is the only item, in which case we
409			 * report an error.
410			 */
411			if (cmd->o.len & F_NOT && av == NULL && len == 0)
412				errx(EX_DATAERR, "not any never matches");
413			continue;
414		}
415
416		/*
417		 * A single IP can be stored alone
418		 */
419		if (masklen == 128 && av == NULL && len == 0) {
420			len = F_INSN_SIZE(struct in6_addr);
421			break;
422		}
423
424		/* Update length and pointer to arguments */
425		len += F_INSN_SIZE(struct in6_addr)*2;
426		d += 2;
427	} /* end while */
428
429	/*
430	 * Total length of the command, remember that 1 is the size of
431	 * the base command.
432	 */
433	if (len + 1 > F_LEN_MASK)
434		errx(EX_DATAERR, "address list too long");
435	cmd->o.len |= len+1;
436	free(oav);
437	return (1);
438}
439
440/*
441 * fills command for ipv6 flow-id filtering
442 * note that the 20 bit flow number is stored in a array of u_int32_t
443 * it's supported lists of flow-id, so in the o.arg1 we store how many
444 * additional flow-id we want to filter, the basic is 1
445 */
446void
447fill_flow6( ipfw_insn_u32 *cmd, char *av, int cblen)
448{
449	u_int32_t type;	 /* Current flow number */
450	u_int16_t nflow = 0;    /* Current flow index */
451	char *s = av;
452	cmd->d[0] = 0;	  /* Initializing the base number*/
453
454	while (s) {
455		CHECK_LENGTH(cblen,
456		    (int)F_INSN_SIZE(ipfw_insn_u32) + nflow + 1);
457
458		av = strsep( &s, ",") ;
459		type = strtoul(av, &av, 0);
460		if (*av != ',' && *av != '\0')
461			errx(EX_DATAERR, "invalid ipv6 flow number %s", av);
462		if (type > 0xfffff)
463			errx(EX_DATAERR, "flow number out of range %s", av);
464		cmd->d[nflow] |= type;
465		nflow++;
466	}
467	if( nflow > 0 ) {
468		cmd->o.opcode = O_FLOW6ID;
469		cmd->o.len |= F_INSN_SIZE(ipfw_insn_u32) + nflow;
470		cmd->o.arg1 = nflow;
471	}
472	else {
473		errx(EX_DATAERR, "invalid ipv6 flow number %s", av);
474	}
475}
476
477ipfw_insn *
478add_srcip6(ipfw_insn *cmd, char *av, int cblen, struct tidx *tstate)
479{
480
481	fill_ip6((ipfw_insn_ip6 *)cmd, av, cblen, tstate);
482	if (cmd->opcode == O_IP_DST_SET)			/* set */
483		cmd->opcode = O_IP_SRC_SET;
484	else if (cmd->opcode == O_IP_DST_LOOKUP)		/* table */
485		cmd->opcode = O_IP_SRC_LOOKUP;
486	else if (F_LEN(cmd) == 0) {				/* any */
487	} else if (F_LEN(cmd) == F_INSN_SIZE(ipfw_insn)) {	/* "me" */
488		cmd->opcode = O_IP6_SRC_ME;
489	} else if (F_LEN(cmd) ==
490	    (F_INSN_SIZE(struct in6_addr) + F_INSN_SIZE(ipfw_insn))) {
491		/* single IP, no mask*/
492		cmd->opcode = O_IP6_SRC;
493	} else {					/* addr/mask opt */
494		cmd->opcode = O_IP6_SRC_MASK;
495	}
496	return cmd;
497}
498
499ipfw_insn *
500add_dstip6(ipfw_insn *cmd, char *av, int cblen, struct tidx *tstate)
501{
502
503	fill_ip6((ipfw_insn_ip6 *)cmd, av, cblen, tstate);
504	if (cmd->opcode == O_IP_DST_SET)			/* set */
505		;
506	else if (cmd->opcode == O_IP_DST_LOOKUP)		/* table */
507		;
508	else if (F_LEN(cmd) == 0) {				/* any */
509	} else if (F_LEN(cmd) == F_INSN_SIZE(ipfw_insn)) {	/* "me" */
510		cmd->opcode = O_IP6_DST_ME;
511	} else if (F_LEN(cmd) ==
512	    (F_INSN_SIZE(struct in6_addr) + F_INSN_SIZE(ipfw_insn))) {
513		/* single IP, no mask*/
514		cmd->opcode = O_IP6_DST;
515	} else {					/* addr/mask opt */
516		cmd->opcode = O_IP6_DST_MASK;
517	}
518	return cmd;
519}
520