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
50static 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
58void
59fill_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
73void
74print_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 */
87void
88print_ip6(struct buf_pr *bp, const ipfw_insn_ip6 *cmd)
89{
90	char trad[255];
91	struct hostent *he = NULL;
92	const struct in6_addr *a = &(cmd->addr6);
93	int len, mb;
94
95	len = F_LEN((const 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((const uint8_t *)&(a[1]), 128);
116
117		if (mb == 128 && g_co.do_resolv)
118			he = gethostbyaddr((const char *)a, sizeof(*a),
119			    AF_INET6);
120
121		if (he != NULL)	     /* resolved to name */
122			bprintf(bp, "%s", he->h_name);
123		else if (mb == 0)	   /* any */
124			bprintf(bp, "any");
125		else {	  /* numeric IP followed by some kind of mask */
126			if (inet_ntop(AF_INET6,  a, trad,
127			    sizeof(trad)) == NULL)
128				bprintf(bp, "Error ntop in print_ip6\n");
129			bprintf(bp, "%s",  trad );
130			if (mb < 0) /* mask not contiguous */
131				bprintf(bp, "/%s", inet_ntop(AF_INET6, &a[1],
132				    trad, sizeof(trad)));
133			else if (mb < 128)
134				bprintf(bp, "/%d", mb);
135		}
136		if (len > 2)
137			bprintf(bp, ",");
138	}
139}
140
141void
142fill_icmp6types(ipfw_insn_icmp6 *cmd, char *av, int cblen)
143{
144       uint8_t type;
145
146       CHECK_LENGTH(cblen, (int)F_INSN_SIZE(ipfw_insn_icmp6));
147       memset(cmd, 0, sizeof(*cmd));
148       while (*av) {
149	       if (*av == ',')
150		       av++;
151	       type = strtoul(av, &av, 0);
152	       if (*av != ',' && *av != '\0')
153		       errx(EX_DATAERR, "invalid ICMP6 type");
154	       /*
155		* XXX: shouldn't this be 0xFF?  I can't see any reason why
156		* we shouldn't be able to filter all possiable values
157		* regardless of the ability of the rest of the kernel to do
158		* anything useful with them.
159		*/
160	       if (type > ICMP6_MAXTYPE)
161		       errx(EX_DATAERR, "ICMP6 type out of range");
162	       cmd->d[type / 32] |= ( 1 << (type % 32));
163       }
164       cmd->o.opcode = O_ICMP6TYPE;
165       cmd->o.len |= F_INSN_SIZE(ipfw_insn_icmp6);
166}
167
168void
169print_icmp6types(struct buf_pr *bp, const ipfw_insn_u32 *cmd)
170{
171	int i, j;
172	char sep= ' ';
173
174	bprintf(bp, " icmp6types");
175	for (i = 0; i < 7; i++)
176		for (j=0; j < 32; ++j) {
177			if ( (cmd->d[i] & (1 << (j))) == 0)
178				continue;
179			bprintf(bp, "%c%d", sep, (i*32 + j));
180			sep = ',';
181		}
182}
183
184void
185print_flow6id(struct buf_pr *bp, const ipfw_insn_u32 *cmd)
186{
187	uint16_t i, limit = cmd->o.arg1;
188	char sep = ',';
189
190	bprintf(bp, " flow-id ");
191	for( i=0; i < limit; ++i) {
192		if (i == limit - 1)
193			sep = ' ';
194		bprintf(bp, "%d%c", cmd->d[i], sep);
195	}
196}
197
198/* structure and define for the extension header in ipv6 */
199static struct _s_x ext6hdrcodes[] = {
200	{ "frag",       EXT_FRAGMENT },
201	{ "hopopt",     EXT_HOPOPTS },
202	{ "route",      EXT_ROUTING },
203	{ "dstopt",     EXT_DSTOPTS },
204	{ "ah",	 EXT_AH },
205	{ "esp",	EXT_ESP },
206	{ "rthdr0",     EXT_RTHDR0 },
207	{ "rthdr2",     EXT_RTHDR2 },
208	{ NULL,	 0 }
209};
210
211/* fills command for the extension header filtering */
212int
213fill_ext6hdr( ipfw_insn *cmd, char *av)
214{
215	int tok;
216	char *s = av;
217
218	cmd->arg1 = 0;
219	while(s) {
220		av = strsep( &s, ",") ;
221		tok = match_token(ext6hdrcodes, av);
222		switch (tok) {
223		case EXT_FRAGMENT:
224			cmd->arg1 |= EXT_FRAGMENT;
225			break;
226		case EXT_HOPOPTS:
227			cmd->arg1 |= EXT_HOPOPTS;
228			break;
229		case EXT_ROUTING:
230			cmd->arg1 |= EXT_ROUTING;
231			break;
232		case EXT_DSTOPTS:
233			cmd->arg1 |= EXT_DSTOPTS;
234			break;
235		case EXT_AH:
236			cmd->arg1 |= EXT_AH;
237			break;
238		case EXT_ESP:
239			cmd->arg1 |= EXT_ESP;
240			break;
241		case EXT_RTHDR0:
242			cmd->arg1 |= EXT_RTHDR0;
243			break;
244		case EXT_RTHDR2:
245			cmd->arg1 |= EXT_RTHDR2;
246			break;
247		default:
248			errx(EX_DATAERR,
249			    "invalid option for ipv6 exten header");
250			break;
251		}
252	}
253	if (cmd->arg1 == 0)
254		return (0);
255	cmd->opcode = O_EXT_HDR;
256	cmd->len |= F_INSN_SIZE(ipfw_insn);
257	return (1);
258}
259
260void
261print_ext6hdr(struct buf_pr *bp, const ipfw_insn *cmd )
262{
263	char sep = ' ';
264
265	bprintf(bp, " extension header:");
266	if (cmd->arg1 & EXT_FRAGMENT) {
267		bprintf(bp, "%cfragmentation", sep);
268		sep = ',';
269	}
270	if (cmd->arg1 & EXT_HOPOPTS) {
271		bprintf(bp, "%chop options", sep);
272		sep = ',';
273	}
274	if (cmd->arg1 & EXT_ROUTING) {
275		bprintf(bp, "%crouting options", sep);
276		sep = ',';
277	}
278	if (cmd->arg1 & EXT_RTHDR0) {
279		bprintf(bp, "%crthdr0", sep);
280		sep = ',';
281	}
282	if (cmd->arg1 & EXT_RTHDR2) {
283		bprintf(bp, "%crthdr2", sep);
284		sep = ',';
285	}
286	if (cmd->arg1 & EXT_DSTOPTS) {
287		bprintf(bp, "%cdestination options", sep);
288		sep = ',';
289	}
290	if (cmd->arg1 & EXT_AH) {
291		bprintf(bp, "%cauthentication header", sep);
292		sep = ',';
293	}
294	if (cmd->arg1 & EXT_ESP) {
295		bprintf(bp, "%cencapsulated security payload", sep);
296	}
297}
298
299/* Try to find ipv6 address by hostname */
300static int
301lookup_host6 (char *host, struct in6_addr *ip6addr)
302{
303	struct hostent *he;
304
305	if (!inet_pton(AF_INET6, host, ip6addr)) {
306		if ((he = gethostbyname2(host, AF_INET6)) == NULL)
307			return(-1);
308		memcpy(ip6addr, he->h_addr_list[0], sizeof( struct in6_addr));
309	}
310	return (0);
311}
312
313
314/*
315 * fill the addr and mask fields in the instruction as appropriate from av.
316 * Update length as appropriate.
317 * The following formats are allowed:
318 *     any     matches any IP6. Actually returns an empty instruction.
319 *     me      returns O_IP6_*_ME
320 *
321 *     03f1::234:123:0342			single IP6 address
322 *     03f1::234:123:0342/24			address/masklen
323 *     03f1::234:123:0342/ffff::ffff:ffff	address/mask
324 *     03f1::234:123:0342/24,03f1::234:123:0343/	List of address
325 *
326 * Set of address (as in ipv6) not supported because ipv6 address
327 * are typically random past the initial prefix.
328 * Return 1 on success, 0 on failure.
329 */
330static int
331fill_ip6(ipfw_insn_ip6 *cmd, char *av, int cblen, struct tidx *tstate)
332{
333	int len = 0;
334	struct in6_addr *d = &(cmd->addr6);
335	char *oav;
336	/*
337	 * Needed for multiple address.
338	 * Note d[1] points to struct in6_add r mask6 of cmd
339	 */
340
341	cmd->o.len &= ~F_LEN_MASK;	/* zero len */
342
343	if (strcmp(av, "any") == 0)
344		return (1);
345
346	/* Set the data for "me" opt */
347	if (strcmp(av, "me") == 0 || strcmp(av, "me6") == 0) {
348		cmd->o.len |= F_INSN_SIZE(ipfw_insn);
349		return (1);
350	}
351
352	if (strncmp(av, "table(", 6) == 0) {
353		fill_table(&cmd->o, av, O_IP_DST_LOOKUP, tstate);
354		return (1);
355	}
356
357	oav = av = strdup(av);
358	while (av) {
359		/*
360		 * After the address we can have '/' indicating a mask,
361		 * or ',' indicating another address follows.
362		 */
363
364		char *p, *q;
365		int masklen;
366		char md = '\0';
367
368		CHECK_LENGTH(cblen,
369		    1 + len + 2 * (int)F_INSN_SIZE(struct in6_addr));
370
371		if ((q = strchr(av, ',')) ) {
372			*q = '\0';
373			q++;
374		}
375
376		if ((p = strchr(av, '/')) ) {
377			md = *p;	/* save the separator */
378			*p = '\0';	/* terminate address string */
379			p++;		/* and skip past it */
380		}
381		/* now p points to NULL, mask or next entry */
382
383		/* lookup stores address in *d as a side effect */
384		if (lookup_host6(av, d) != 0) {
385			/* XXX: failed. Free memory and go */
386			errx(EX_DATAERR, "bad address \"%s\"", av);
387		}
388		/* next, look at the mask, if any */
389		if (md == '/' && strchr(p, ':')) {
390			if (!inet_pton(AF_INET6, p, &d[1]))
391				errx(EX_DATAERR, "bad mask \"%s\"", p);
392
393			masklen = contigmask((uint8_t *)&(d[1]), 128);
394		} else {
395			masklen = (md == '/') ? atoi(p) : 128;
396			if (masklen > 128 || masklen < 0)
397				errx(EX_DATAERR, "bad width \"%s\''", p);
398			else
399				n2mask(&d[1], masklen);
400		}
401
402		APPLY_MASK(d, &d[1]);   /* mask base address with mask */
403
404		av = q;
405
406		/* Check this entry */
407		if (masklen == 0) {
408			/*
409			 * 'any' turns the entire list into a NOP.
410			 * 'not any' never matches, so it is removed from the
411			 * list unless it is the only item, in which case we
412			 * report an error.
413			 */
414			if (cmd->o.len & F_NOT && av == NULL && len == 0)
415				errx(EX_DATAERR, "not any never matches");
416			continue;
417		}
418
419		/*
420		 * A single IP can be stored alone
421		 */
422		if (masklen == 128 && av == NULL && len == 0) {
423			len = F_INSN_SIZE(struct in6_addr);
424			break;
425		}
426
427		/* Update length and pointer to arguments */
428		len += F_INSN_SIZE(struct in6_addr)*2;
429		d += 2;
430	} /* end while */
431
432	/*
433	 * Total length of the command, remember that 1 is the size of
434	 * the base command.
435	 */
436	if (len + 1 > F_LEN_MASK)
437		errx(EX_DATAERR, "address list too long");
438	cmd->o.len |= len+1;
439	free(oav);
440	return (1);
441}
442
443/*
444 * fills command for ipv6 flow-id filtering
445 * note that the 20 bit flow number is stored in a array of u_int32_t
446 * it's supported lists of flow-id, so in the o.arg1 we store how many
447 * additional flow-id we want to filter, the basic is 1
448 */
449void
450fill_flow6( ipfw_insn_u32 *cmd, char *av, int cblen)
451{
452	u_int32_t type;	 /* Current flow number */
453	u_int16_t nflow = 0;    /* Current flow index */
454	char *s = av;
455	cmd->d[0] = 0;	  /* Initializing the base number*/
456
457	while (s) {
458		CHECK_LENGTH(cblen,
459		    (int)F_INSN_SIZE(ipfw_insn_u32) + nflow + 1);
460
461		av = strsep( &s, ",") ;
462		type = strtoul(av, &av, 0);
463		if (*av != ',' && *av != '\0')
464			errx(EX_DATAERR, "invalid ipv6 flow number %s", av);
465		if (type > 0xfffff)
466			errx(EX_DATAERR, "flow number out of range %s", av);
467		cmd->d[nflow] |= type;
468		nflow++;
469	}
470	if( nflow > 0 ) {
471		cmd->o.opcode = O_FLOW6ID;
472		cmd->o.len |= F_INSN_SIZE(ipfw_insn_u32) + nflow;
473		cmd->o.arg1 = nflow;
474	}
475	else {
476		errx(EX_DATAERR, "invalid ipv6 flow number %s", av);
477	}
478}
479
480ipfw_insn *
481add_srcip6(ipfw_insn *cmd, char *av, int cblen, struct tidx *tstate)
482{
483
484	fill_ip6((ipfw_insn_ip6 *)cmd, av, cblen, tstate);
485	if (cmd->opcode == O_IP_DST_SET)			/* set */
486		cmd->opcode = O_IP_SRC_SET;
487	else if (cmd->opcode == O_IP_DST_LOOKUP)		/* table */
488		cmd->opcode = O_IP_SRC_LOOKUP;
489	else if (F_LEN(cmd) == 0) {				/* any */
490	} else if (F_LEN(cmd) == F_INSN_SIZE(ipfw_insn)) {	/* "me" */
491		cmd->opcode = O_IP6_SRC_ME;
492	} else if (F_LEN(cmd) ==
493	    (F_INSN_SIZE(struct in6_addr) + F_INSN_SIZE(ipfw_insn))) {
494		/* single IP, no mask*/
495		cmd->opcode = O_IP6_SRC;
496	} else {					/* addr/mask opt */
497		cmd->opcode = O_IP6_SRC_MASK;
498	}
499	return cmd;
500}
501
502ipfw_insn *
503add_dstip6(ipfw_insn *cmd, char *av, int cblen, struct tidx *tstate)
504{
505
506	fill_ip6((ipfw_insn_ip6 *)cmd, av, cblen, tstate);
507	if (cmd->opcode == O_IP_DST_SET)			/* set */
508		;
509	else if (cmd->opcode == O_IP_DST_LOOKUP)		/* table */
510		;
511	else if (F_LEN(cmd) == 0) {				/* any */
512	} else if (F_LEN(cmd) == F_INSN_SIZE(ipfw_insn)) {	/* "me" */
513		cmd->opcode = O_IP6_DST_ME;
514	} else if (F_LEN(cmd) ==
515	    (F_INSN_SIZE(struct in6_addr) + F_INSN_SIZE(ipfw_insn))) {
516		/* single IP, no mask*/
517		cmd->opcode = O_IP6_DST;
518	} else {					/* addr/mask opt */
519		cmd->opcode = O_IP6_DST_MASK;
520	}
521	return cmd;
522}
523