1/*
2 * link_iptnl.c	ipip and sit driver module
3 *
4 *		This program is free software; you can redistribute it and/or
5 *		modify it under the terms of the GNU General Public License
6 *		as published by the Free Software Foundation; either version
7 *		2 of the License, or (at your option) any later version.
8 *
9 * Authors:	Nicolas Dichtel <nicolas.dichtel@6wind.com>
10 *
11 */
12
13#include <string.h>
14#include <net/if.h>
15#include <sys/types.h>
16#include <sys/socket.h>
17#include <arpa/inet.h>
18
19#include <linux/ip.h>
20#include <linux/if_tunnel.h>
21#include "rt_names.h"
22#include "utils.h"
23#include "ip_common.h"
24#include "tunnel.h"
25
26static void print_usage(FILE *f, int sit)
27{
28	fprintf(f, "Usage: ip link { add | set | change | replace | del } NAME\n");
29	fprintf(f, "          type { ipip | sit } [ remote ADDR ] [ local ADDR ]\n");
30	fprintf(f, "          [ ttl TTL ] [ tos TOS ] [ [no]pmtudisc ] [ dev PHYS_DEV ]\n");
31	fprintf(f, "          [ 6rd-prefix ADDR ] [ 6rd-relay_prefix ADDR ] [ 6rd-reset ]\n");
32	fprintf(f, "          [ noencap ] [ encap { fou | gue | none } ]\n");
33	fprintf(f, "          [ encap-sport PORT ] [ encap-dport PORT ]\n");
34	fprintf(f, "          [ [no]encap-csum ] [ [no]encap-csum6 ] [ [no]encap-remcsum ]\n");
35	if (sit) {
36		fprintf(f, "          [ mode { ip6ip | ipip | any } ]\n");
37		fprintf(f, "          [ isatap ]\n");
38	}
39	fprintf(f, "\n");
40	fprintf(f, "Where: NAME := STRING\n");
41	fprintf(f, "       ADDR := { IP_ADDRESS | any }\n");
42	fprintf(f, "       TOS  := { NUMBER | inherit }\n");
43	fprintf(f, "       TTL  := { 1..255 | inherit }\n");
44}
45
46static void usage(int sit) __attribute__((noreturn));
47static void usage(int sit)
48{
49	print_usage(stderr, sit);
50	exit(-1);
51}
52
53static int iptunnel_parse_opt(struct link_util *lu, int argc, char **argv,
54			      struct nlmsghdr *n)
55{
56	struct {
57		struct nlmsghdr n;
58		struct ifinfomsg i;
59		char buf[2048];
60	} req;
61	struct ifinfomsg *ifi = (struct ifinfomsg *)(n + 1);
62	struct rtattr *tb[IFLA_MAX + 1];
63	struct rtattr *linkinfo[IFLA_INFO_MAX+1];
64	struct rtattr *iptuninfo[IFLA_IPTUN_MAX + 1];
65	int len;
66	__u32 link = 0;
67	__u32 laddr = 0;
68	__u32 raddr = 0;
69	__u8 ttl = 0;
70	__u8 tos = 0;
71	__u8 pmtudisc = 1;
72	__u16 iflags = 0;
73	__u8 proto = 0;
74	struct in6_addr ip6rdprefix;
75	__u16 ip6rdprefixlen = 0;
76	__u32 ip6rdrelayprefix = 0;
77	__u16 ip6rdrelayprefixlen = 0;
78	__u16 encaptype = 0;
79	__u16 encapflags = 0;
80	__u16 encapsport = 0;
81	__u16 encapdport = 0;
82
83	memset(&ip6rdprefix, 0, sizeof(ip6rdprefix));
84
85	if (!(n->nlmsg_flags & NLM_F_CREATE)) {
86		memset(&req, 0, sizeof(req));
87
88		req.n.nlmsg_len = NLMSG_LENGTH(sizeof(*ifi));
89		req.n.nlmsg_flags = NLM_F_REQUEST;
90		req.n.nlmsg_type = RTM_GETLINK;
91		req.i.ifi_family = preferred_family;
92		req.i.ifi_index = ifi->ifi_index;
93
94		if (rtnl_talk(&rth, &req.n, &req.n, sizeof(req)) < 0) {
95get_failed:
96			fprintf(stderr,
97				"Failed to get existing tunnel info.\n");
98			return -1;
99		}
100
101		len = req.n.nlmsg_len;
102		len -= NLMSG_LENGTH(sizeof(*ifi));
103		if (len < 0)
104			goto get_failed;
105
106		parse_rtattr(tb, IFLA_MAX, IFLA_RTA(&req.i), len);
107
108		if (!tb[IFLA_LINKINFO])
109			goto get_failed;
110
111		parse_rtattr_nested(linkinfo, IFLA_INFO_MAX, tb[IFLA_LINKINFO]);
112
113		if (!linkinfo[IFLA_INFO_DATA])
114			goto get_failed;
115
116		parse_rtattr_nested(iptuninfo, IFLA_IPTUN_MAX,
117				    linkinfo[IFLA_INFO_DATA]);
118
119		if (iptuninfo[IFLA_IPTUN_LOCAL])
120			laddr = rta_getattr_u32(iptuninfo[IFLA_IPTUN_LOCAL]);
121
122		if (iptuninfo[IFLA_IPTUN_REMOTE])
123			raddr = rta_getattr_u32(iptuninfo[IFLA_IPTUN_REMOTE]);
124
125		if (iptuninfo[IFLA_IPTUN_TTL])
126			ttl = rta_getattr_u8(iptuninfo[IFLA_IPTUN_TTL]);
127
128		if (iptuninfo[IFLA_IPTUN_TOS])
129			tos = rta_getattr_u8(iptuninfo[IFLA_IPTUN_TOS]);
130
131		if (iptuninfo[IFLA_IPTUN_PMTUDISC])
132			pmtudisc =
133				rta_getattr_u8(iptuninfo[IFLA_IPTUN_PMTUDISC]);
134
135		if (iptuninfo[IFLA_IPTUN_FLAGS])
136			iflags = rta_getattr_u16(iptuninfo[IFLA_IPTUN_FLAGS]);
137
138		if (iptuninfo[IFLA_IPTUN_LINK])
139			link = rta_getattr_u32(iptuninfo[IFLA_IPTUN_LINK]);
140
141		if (iptuninfo[IFLA_IPTUN_PROTO])
142			proto = rta_getattr_u8(iptuninfo[IFLA_IPTUN_PROTO]);
143
144		if (iptuninfo[IFLA_IPTUN_ENCAP_TYPE])
145			encaptype = rta_getattr_u16(iptuninfo[IFLA_IPTUN_ENCAP_TYPE]);
146		if (iptuninfo[IFLA_IPTUN_ENCAP_FLAGS])
147			encapflags = rta_getattr_u16(iptuninfo[IFLA_IPTUN_ENCAP_FLAGS]);
148		if (iptuninfo[IFLA_IPTUN_ENCAP_SPORT])
149			encapsport = rta_getattr_u16(iptuninfo[IFLA_IPTUN_ENCAP_SPORT]);
150		if (iptuninfo[IFLA_IPTUN_ENCAP_DPORT])
151			encapdport = rta_getattr_u16(iptuninfo[IFLA_IPTUN_ENCAP_DPORT]);
152		if (iptuninfo[IFLA_IPTUN_6RD_PREFIX])
153			memcpy(&ip6rdprefix,
154			       RTA_DATA(iptuninfo[IFLA_IPTUN_6RD_PREFIX]),
155			       sizeof(laddr));
156
157		if (iptuninfo[IFLA_IPTUN_6RD_PREFIXLEN])
158			ip6rdprefixlen =
159				rta_getattr_u16(iptuninfo[IFLA_IPTUN_6RD_PREFIXLEN]);
160
161		if (iptuninfo[IFLA_IPTUN_6RD_RELAY_PREFIX])
162			ip6rdrelayprefix =
163				rta_getattr_u32(iptuninfo[IFLA_IPTUN_6RD_RELAY_PREFIX]);
164
165		if (iptuninfo[IFLA_IPTUN_6RD_RELAY_PREFIXLEN])
166			ip6rdrelayprefixlen =
167				rta_getattr_u16(iptuninfo[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]);
168	}
169
170	while (argc > 0) {
171		if (strcmp(*argv, "remote") == 0) {
172			NEXT_ARG();
173			if (strcmp(*argv, "any"))
174				raddr = get_addr32(*argv);
175			else
176				raddr = 0;
177		} else if (strcmp(*argv, "local") == 0) {
178			NEXT_ARG();
179			if (strcmp(*argv, "any"))
180				laddr = get_addr32(*argv);
181			else
182				laddr = 0;
183		} else if (matches(*argv, "dev") == 0) {
184			NEXT_ARG();
185			link = if_nametoindex(*argv);
186			if (link == 0)
187				invarg("\"dev\" is invalid", *argv);
188		} else if (strcmp(*argv, "ttl") == 0 ||
189			   strcmp(*argv, "hoplimit") == 0) {
190			NEXT_ARG();
191			if (strcmp(*argv, "inherit") != 0) {
192				if (get_u8(&ttl, *argv, 0))
193					invarg("invalid TTL\n", *argv);
194			} else
195				ttl = 0;
196		} else if (strcmp(*argv, "tos") == 0 ||
197			   strcmp(*argv, "tclass") == 0 ||
198			   matches(*argv, "dsfield") == 0) {
199			__u32 uval;
200			NEXT_ARG();
201			if (strcmp(*argv, "inherit") != 0) {
202				if (rtnl_dsfield_a2n(&uval, *argv))
203					invarg("bad TOS value", *argv);
204				tos = uval;
205			} else
206				tos = 1;
207		} else if (strcmp(*argv, "nopmtudisc") == 0) {
208			pmtudisc = 0;
209		} else if (strcmp(*argv, "pmtudisc") == 0) {
210			pmtudisc = 1;
211		} else if (strcmp(lu->id, "sit") == 0 &&
212			   strcmp(*argv, "isatap") == 0) {
213			iflags |= SIT_ISATAP;
214		} else if (strcmp(lu->id, "sit") == 0 &&
215			   strcmp(*argv, "mode") == 0) {
216			NEXT_ARG();
217			if (strcmp(*argv, "ipv6/ipv4") == 0 ||
218			    strcmp(*argv, "ip6ip") == 0)
219				proto = IPPROTO_IPV6;
220			else if (strcmp(*argv, "ipv4/ipv4") == 0 ||
221				 strcmp(*argv, "ipip") == 0 ||
222				 strcmp(*argv, "ip4ip4") == 0)
223				proto = IPPROTO_IPIP;
224			else if (strcmp(*argv, "any/ipv4") == 0 ||
225				 strcmp(*argv, "any") == 0)
226				proto = 0;
227			else
228				invarg("Cannot guess tunnel mode.", *argv);
229		} else if (strcmp(*argv, "noencap") == 0) {
230			encaptype = TUNNEL_ENCAP_NONE;
231		} else if (strcmp(*argv, "encap") == 0) {
232			NEXT_ARG();
233			if (strcmp(*argv, "fou") == 0)
234				encaptype = TUNNEL_ENCAP_FOU;
235			else if (strcmp(*argv, "gue") == 0)
236				encaptype = TUNNEL_ENCAP_GUE;
237			else if (strcmp(*argv, "none") == 0)
238				encaptype = TUNNEL_ENCAP_NONE;
239			else
240				invarg("Invalid encap type.", *argv);
241		} else if (strcmp(*argv, "encap-sport") == 0) {
242			NEXT_ARG();
243			if (strcmp(*argv, "auto") == 0)
244				encapsport = 0;
245			else if (get_u16(&encapsport, *argv, 0))
246				invarg("Invalid source port.", *argv);
247		} else if (strcmp(*argv, "encap-dport") == 0) {
248			NEXT_ARG();
249			if (get_u16(&encapdport, *argv, 0))
250				invarg("Invalid destination port.", *argv);
251		} else if (strcmp(*argv, "encap-csum") == 0) {
252			encapflags |= TUNNEL_ENCAP_FLAG_CSUM;
253		} else if (strcmp(*argv, "noencap-csum") == 0) {
254			encapflags &= ~TUNNEL_ENCAP_FLAG_CSUM;
255		} else if (strcmp(*argv, "encap-udp6-csum") == 0) {
256			encapflags |= TUNNEL_ENCAP_FLAG_CSUM6;
257		} else if (strcmp(*argv, "noencap-udp6-csum") == 0) {
258			encapflags &= ~TUNNEL_ENCAP_FLAG_CSUM6;
259		} else if (strcmp(*argv, "encap-remcsum") == 0) {
260			encapflags |= TUNNEL_ENCAP_FLAG_REMCSUM;
261		} else if (strcmp(*argv, "noencap-remcsum") == 0) {
262			encapflags &= ~TUNNEL_ENCAP_FLAG_REMCSUM;
263		} else if (strcmp(*argv, "6rd-prefix") == 0) {
264			inet_prefix prefix;
265			NEXT_ARG();
266			if (get_prefix(&prefix, *argv, AF_INET6))
267				invarg("invalid 6rd_prefix\n", *argv);
268			memcpy(&ip6rdprefix, prefix.data, 16);
269			ip6rdprefixlen = prefix.bitlen;
270		} else if (strcmp(*argv, "6rd-relay_prefix") == 0) {
271			inet_prefix prefix;
272			NEXT_ARG();
273			if (get_prefix(&prefix, *argv, AF_INET))
274				invarg("invalid 6rd-relay_prefix\n", *argv);
275			memcpy(&ip6rdrelayprefix, prefix.data, 4);
276			ip6rdrelayprefixlen = prefix.bitlen;
277		} else if (strcmp(*argv, "6rd-reset") == 0) {
278			inet_prefix prefix;
279			get_prefix(&prefix, "2002::", AF_INET6);
280			memcpy(&ip6rdprefix, prefix.data, 16);
281			ip6rdprefixlen = 16;
282			ip6rdrelayprefix = 0;
283			ip6rdrelayprefixlen = 0;
284		} else
285			usage(strcmp(lu->id, "sit") == 0);
286		argc--, argv++;
287	}
288
289	if (ttl && pmtudisc == 0) {
290		fprintf(stderr, "ttl != 0 and nopmtudisc are incompatible\n");
291		exit(-1);
292	}
293
294	addattr32(n, 1024, IFLA_IPTUN_LINK, link);
295	addattr32(n, 1024, IFLA_IPTUN_LOCAL, laddr);
296	addattr32(n, 1024, IFLA_IPTUN_REMOTE, raddr);
297	addattr8(n, 1024, IFLA_IPTUN_TTL, ttl);
298	addattr8(n, 1024, IFLA_IPTUN_TOS, tos);
299	addattr8(n, 1024, IFLA_IPTUN_PMTUDISC, pmtudisc);
300
301	addattr16(n, 1024, IFLA_IPTUN_ENCAP_TYPE, encaptype);
302	addattr16(n, 1024, IFLA_IPTUN_ENCAP_FLAGS, encapflags);
303	addattr16(n, 1024, IFLA_IPTUN_ENCAP_SPORT, htons(encapsport));
304	addattr16(n, 1024, IFLA_IPTUN_ENCAP_DPORT, htons(encapdport));
305
306	if (strcmp(lu->id, "sit") == 0) {
307		addattr16(n, 1024, IFLA_IPTUN_FLAGS, iflags);
308		addattr8(n, 1024, IFLA_IPTUN_PROTO, proto);
309		if (ip6rdprefixlen) {
310			addattr_l(n, 1024, IFLA_IPTUN_6RD_PREFIX,
311				  &ip6rdprefix, sizeof(ip6rdprefix));
312			addattr16(n, 1024, IFLA_IPTUN_6RD_PREFIXLEN,
313				  ip6rdprefixlen);
314			addattr32(n, 1024, IFLA_IPTUN_6RD_RELAY_PREFIX,
315				  ip6rdrelayprefix);
316			addattr16(n, 1024, IFLA_IPTUN_6RD_RELAY_PREFIXLEN,
317				  ip6rdrelayprefixlen);
318		}
319	}
320
321	return 0;
322}
323
324static void iptunnel_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
325{
326	char s1[1024];
327	char s2[64];
328	const char *local = "any";
329	const char *remote = "any";
330
331	if (!tb)
332		return;
333
334	if (tb[IFLA_IPTUN_REMOTE]) {
335		unsigned addr = rta_getattr_u32(tb[IFLA_IPTUN_REMOTE]);
336
337		if (addr)
338			remote = format_host(AF_INET, 4, &addr, s1, sizeof(s1));
339	}
340
341	fprintf(f, "remote %s ", remote);
342
343	if (tb[IFLA_IPTUN_LOCAL]) {
344		unsigned addr = rta_getattr_u32(tb[IFLA_IPTUN_LOCAL]);
345
346		if (addr)
347			local = format_host(AF_INET, 4, &addr, s1, sizeof(s1));
348	}
349
350	fprintf(f, "local %s ", local);
351
352	if (tb[IFLA_IPTUN_LINK] && rta_getattr_u32(tb[IFLA_IPTUN_LINK])) {
353		unsigned link = rta_getattr_u32(tb[IFLA_IPTUN_LINK]);
354		const char *n = if_indextoname(link, s2);
355
356		if (n)
357			fprintf(f, "dev %s ", n);
358		else
359			fprintf(f, "dev %u ", link);
360	}
361
362	if (tb[IFLA_IPTUN_TTL] && rta_getattr_u8(tb[IFLA_IPTUN_TTL]))
363		fprintf(f, "ttl %d ", rta_getattr_u8(tb[IFLA_IPTUN_TTL]));
364	else
365		fprintf(f, "ttl inherit ");
366
367	if (tb[IFLA_IPTUN_TOS] && rta_getattr_u8(tb[IFLA_IPTUN_TOS])) {
368		int tos = rta_getattr_u8(tb[IFLA_IPTUN_TOS]);
369
370		fputs("tos ", f);
371		if (tos == 1)
372			fputs("inherit ", f);
373		else
374			fprintf(f, "0x%x ", tos);
375	}
376
377	if (tb[IFLA_IPTUN_PMTUDISC] && rta_getattr_u8(tb[IFLA_IPTUN_PMTUDISC]))
378		fprintf(f, "pmtudisc ");
379	else
380		fprintf(f, "nopmtudisc ");
381
382	if (tb[IFLA_IPTUN_FLAGS]) {
383		__u16 iflags = rta_getattr_u16(tb[IFLA_IPTUN_FLAGS]);
384
385		if (iflags & SIT_ISATAP)
386			fprintf(f, "isatap ");
387	}
388
389	if (tb[IFLA_IPTUN_6RD_PREFIXLEN] &&
390	    *(__u16 *)RTA_DATA(tb[IFLA_IPTUN_6RD_PREFIXLEN])) {
391		__u16 prefixlen = rta_getattr_u16(tb[IFLA_IPTUN_6RD_PREFIXLEN]);
392		__u16 relayprefixlen =
393			rta_getattr_u16(tb[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]);
394		__u32 relayprefix =
395			rta_getattr_u32(tb[IFLA_IPTUN_6RD_RELAY_PREFIX]);
396
397		printf("6rd-prefix %s/%u ",
398		       inet_ntop(AF_INET6, RTA_DATA(tb[IFLA_IPTUN_6RD_PREFIX]),
399				 s1, sizeof(s1)),
400		       prefixlen);
401		if (relayprefix) {
402			printf("6rd-relay_prefix %s/%u ",
403			       format_host(AF_INET, 4, &relayprefix, s1,
404					   sizeof(s1)),
405			       relayprefixlen);
406		}
407	}
408
409	if (tb[IFLA_IPTUN_ENCAP_TYPE] &&
410	    *(__u16 *)RTA_DATA(tb[IFLA_IPTUN_ENCAP_TYPE]) != TUNNEL_ENCAP_NONE) {
411		__u16 type = rta_getattr_u16(tb[IFLA_IPTUN_ENCAP_TYPE]);
412		__u16 flags = rta_getattr_u16(tb[IFLA_IPTUN_ENCAP_FLAGS]);
413		__u16 sport = rta_getattr_u16(tb[IFLA_IPTUN_ENCAP_SPORT]);
414		__u16 dport = rta_getattr_u16(tb[IFLA_IPTUN_ENCAP_DPORT]);
415
416		fputs("encap ", f);
417		switch (type) {
418		case TUNNEL_ENCAP_FOU:
419			fputs("fou ", f);
420			break;
421		case TUNNEL_ENCAP_GUE:
422			fputs("gue ", f);
423			break;
424		default:
425			fputs("unknown ", f);
426			break;
427		}
428
429		if (sport == 0)
430			fputs("encap-sport auto ", f);
431		else
432			fprintf(f, "encap-sport %u", ntohs(sport));
433
434		fprintf(f, "encap-dport %u ", ntohs(dport));
435
436		if (flags & TUNNEL_ENCAP_FLAG_CSUM)
437			fputs("encap-csum ", f);
438		else
439			fputs("noencap-csum ", f);
440
441		if (flags & TUNNEL_ENCAP_FLAG_CSUM6)
442			fputs("encap-csum6 ", f);
443		else
444			fputs("noencap-csum6 ", f);
445
446		if (flags & TUNNEL_ENCAP_FLAG_REMCSUM)
447			fputs("encap-remcsum ", f);
448		else
449			fputs("noencap-remcsum ", f);
450	}
451}
452
453static void iptunnel_print_help(struct link_util *lu, int argc, char **argv,
454	FILE *f)
455{
456	print_usage(f, strcmp(lu->id, "sit") == 0);
457}
458
459struct link_util ipip_link_util = {
460	.id = "ipip",
461	.maxattr = IFLA_IPTUN_MAX,
462	.parse_opt = iptunnel_parse_opt,
463	.print_opt = iptunnel_print_opt,
464	.print_help = iptunnel_print_help,
465};
466
467struct link_util sit_link_util = {
468	.id = "sit",
469	.maxattr = IFLA_IPTUN_MAX,
470	.parse_opt = iptunnel_parse_opt,
471	.print_opt = iptunnel_print_opt,
472	.print_help = iptunnel_print_help,
473};
474