1 /*
2 * link_ip6tnl.c ip6tnl 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 <linux/ip6_tunnel.h>
22 #include "rt_names.h"
23 #include "utils.h"
24 #include "ip_common.h"
25 #include "tunnel.h"
26
27 #define IP6_FLOWINFO_TCLASS htonl(0x0FF00000)
28 #define IP6_FLOWINFO_FLOWLABEL htonl(0x000FFFFF)
29
30 #define DEFAULT_TNL_HOP_LIMIT (64)
31
print_usage(FILE * f)32 static void print_usage(FILE *f)
33 {
34 fprintf(f, "Usage: ip link { add | set | change | replace | del } NAME\n");
35 fprintf(f, " [ mode { ip6ip6 | ipip6 | any } ]\n");
36 fprintf(f, " type ip6tnl [ remote ADDR ] [ local ADDR ]\n");
37 fprintf(f, " [ dev PHYS_DEV ] [ encaplimit ELIM ]\n");
38 fprintf(f ," [ hoplimit HLIM ] [ tclass TCLASS ] [ flowlabel FLOWLABEL ]\n");
39 fprintf(f, " [ dscp inherit ] [ fwmark inherit ]\n");
40 fprintf(f, "\n");
41 fprintf(f, "Where: NAME := STRING\n");
42 fprintf(f, " ADDR := IPV6_ADDRESS\n");
43 fprintf(f, " ELIM := { none | 0..255 }(default=%d)\n",
44 IPV6_DEFAULT_TNL_ENCAP_LIMIT);
45 fprintf(f, " HLIM := 0..255 (default=%d)\n",
46 DEFAULT_TNL_HOP_LIMIT);
47 fprintf(f, " TCLASS := { 0x0..0xff | inherit }\n");
48 fprintf(f, " FLOWLABEL := { 0x0..0xfffff | inherit }\n");
49 }
50
51 static void usage(void) __attribute__((noreturn));
usage(void)52 static void usage(void)
53 {
54 print_usage(stderr);
55 exit(-1);
56 }
57
ip6tunnel_parse_opt(struct link_util * lu,int argc,char ** argv,struct nlmsghdr * n)58 static int ip6tunnel_parse_opt(struct link_util *lu, int argc, char **argv,
59 struct nlmsghdr *n)
60 {
61 struct {
62 struct nlmsghdr n;
63 struct ifinfomsg i;
64 char buf[2048];
65 } req;
66 struct ifinfomsg *ifi = (struct ifinfomsg *)(n + 1);
67 struct rtattr *tb[IFLA_MAX + 1];
68 struct rtattr *linkinfo[IFLA_INFO_MAX+1];
69 struct rtattr *iptuninfo[IFLA_IPTUN_MAX + 1];
70 int len;
71 struct in6_addr laddr;
72 struct in6_addr raddr;
73 __u8 hop_limit = DEFAULT_TNL_HOP_LIMIT;
74 __u8 encap_limit = IPV6_DEFAULT_TNL_ENCAP_LIMIT;
75 __u32 flowinfo = 0;
76 __u32 flags = 0;
77 __u32 link = 0;
78 __u8 proto = 0;
79
80 memset(&laddr, 0, sizeof(laddr));
81 memset(&raddr, 0, sizeof(raddr));
82
83 if (!(n->nlmsg_flags & NLM_F_CREATE)) {
84 memset(&req, 0, sizeof(req));
85
86 req.n.nlmsg_len = NLMSG_LENGTH(sizeof(*ifi));
87 req.n.nlmsg_flags = NLM_F_REQUEST;
88 req.n.nlmsg_type = RTM_GETLINK;
89 req.i.ifi_family = preferred_family;
90 req.i.ifi_index = ifi->ifi_index;
91
92 if (rtnl_talk(&rth, &req.n, &req.n, sizeof(req)) < 0) {
93 get_failed:
94 fprintf(stderr,
95 "Failed to get existing tunnel info.\n");
96 return -1;
97 }
98
99 len = req.n.nlmsg_len;
100 len -= NLMSG_LENGTH(sizeof(*ifi));
101 if (len < 0)
102 goto get_failed;
103
104 parse_rtattr(tb, IFLA_MAX, IFLA_RTA(&req.i), len);
105
106 if (!tb[IFLA_LINKINFO])
107 goto get_failed;
108
109 parse_rtattr_nested(linkinfo, IFLA_INFO_MAX, tb[IFLA_LINKINFO]);
110
111 if (!linkinfo[IFLA_INFO_DATA])
112 goto get_failed;
113
114 parse_rtattr_nested(iptuninfo, IFLA_IPTUN_MAX,
115 linkinfo[IFLA_INFO_DATA]);
116
117 if (iptuninfo[IFLA_IPTUN_LOCAL])
118 memcpy(&laddr, RTA_DATA(iptuninfo[IFLA_IPTUN_LOCAL]),
119 sizeof(laddr));
120
121 if (iptuninfo[IFLA_IPTUN_REMOTE])
122 memcpy(&raddr, RTA_DATA(iptuninfo[IFLA_IPTUN_REMOTE]),
123 sizeof(raddr));
124
125 if (iptuninfo[IFLA_IPTUN_TTL])
126 hop_limit = rta_getattr_u8(iptuninfo[IFLA_IPTUN_TTL]);
127
128 if (iptuninfo[IFLA_IPTUN_ENCAP_LIMIT])
129 encap_limit = rta_getattr_u8(iptuninfo[IFLA_IPTUN_ENCAP_LIMIT]);
130
131 if (iptuninfo[IFLA_IPTUN_FLOWINFO])
132 flowinfo = rta_getattr_u32(iptuninfo[IFLA_IPTUN_FLOWINFO]);
133
134 if (iptuninfo[IFLA_IPTUN_FLAGS])
135 flags = rta_getattr_u32(iptuninfo[IFLA_IPTUN_FLAGS]);
136
137 if (iptuninfo[IFLA_IPTUN_LINK])
138 link = rta_getattr_u32(iptuninfo[IFLA_IPTUN_LINK]);
139
140 if (iptuninfo[IFLA_IPTUN_PROTO])
141 proto = rta_getattr_u8(iptuninfo[IFLA_IPTUN_PROTO]);
142 }
143
144 while (argc > 0) {
145 if (matches(*argv, "mode") == 0) {
146 NEXT_ARG();
147 if (strcmp(*argv, "ipv6/ipv6") == 0 ||
148 strcmp(*argv, "ip6ip6") == 0)
149 proto = IPPROTO_IPV6;
150 else if (strcmp(*argv, "ip/ipv6") == 0 ||
151 strcmp(*argv, "ipv4/ipv6") == 0 ||
152 strcmp(*argv, "ipip6") == 0 ||
153 strcmp(*argv, "ip4ip6") == 0)
154 proto = IPPROTO_IPIP;
155 else if (strcmp(*argv, "any/ipv6") == 0 ||
156 strcmp(*argv, "any") == 0)
157 proto = 0;
158 else
159 invarg("Cannot guess tunnel mode.", *argv);
160 } else if (strcmp(*argv, "remote") == 0) {
161 inet_prefix addr;
162 NEXT_ARG();
163 get_prefix(&addr, *argv, preferred_family);
164 if (addr.family == AF_UNSPEC)
165 invarg("\"remote\" address family is AF_UNSPEC", *argv);
166 memcpy(&raddr, addr.data, addr.bytelen);
167 } else if (strcmp(*argv, "local") == 0) {
168 inet_prefix addr;
169 NEXT_ARG();
170 get_prefix(&addr, *argv, preferred_family);
171 if (addr.family == AF_UNSPEC)
172 invarg("\"local\" address family is AF_UNSPEC", *argv);
173 memcpy(&laddr, addr.data, addr.bytelen);
174 } else if (matches(*argv, "dev") == 0) {
175 NEXT_ARG();
176 link = if_nametoindex(*argv);
177 if (link == 0)
178 invarg("\"dev\" is invalid", *argv);
179 } else if (strcmp(*argv, "hoplimit") == 0 ||
180 strcmp(*argv, "ttl") == 0 ||
181 strcmp(*argv, "hlim") == 0) {
182 __u8 uval;
183 NEXT_ARG();
184 if (get_u8(&uval, *argv, 0))
185 invarg("invalid HLIM", *argv);
186 hop_limit = uval;
187 } else if (matches(*argv, "encaplimit") == 0) {
188 NEXT_ARG();
189 if (strcmp(*argv, "none") == 0) {
190 flags |= IP6_TNL_F_IGN_ENCAP_LIMIT;
191 } else {
192 __u8 uval;
193 if (get_u8(&uval, *argv, 0) < -1)
194 invarg("invalid ELIM", *argv);
195 encap_limit = uval;
196 flags &= ~IP6_TNL_F_IGN_ENCAP_LIMIT;
197 }
198 } else if (strcmp(*argv, "tclass") == 0 ||
199 strcmp(*argv, "tc") == 0 ||
200 strcmp(*argv, "tos") == 0 ||
201 matches(*argv, "dsfield") == 0) {
202 __u8 uval;
203 NEXT_ARG();
204 flowinfo &= ~IP6_FLOWINFO_TCLASS;
205 if (strcmp(*argv, "inherit") == 0)
206 flags |= IP6_TNL_F_USE_ORIG_TCLASS;
207 else {
208 if (get_u8(&uval, *argv, 16))
209 invarg("invalid TClass", *argv);
210 flowinfo |= htonl((__u32)uval << 20) & IP6_FLOWINFO_TCLASS;
211 flags &= ~IP6_TNL_F_USE_ORIG_TCLASS;
212 }
213 } else if (strcmp(*argv, "flowlabel") == 0 ||
214 strcmp(*argv, "fl") == 0) {
215 __u32 uval;
216 NEXT_ARG();
217 flowinfo &= ~IP6_FLOWINFO_FLOWLABEL;
218 if (strcmp(*argv, "inherit") == 0)
219 flags |= IP6_TNL_F_USE_ORIG_FLOWLABEL;
220 else {
221 if (get_u32(&uval, *argv, 16))
222 invarg("invalid Flowlabel", *argv);
223 if (uval > 0xFFFFF)
224 invarg("invalid Flowlabel", *argv);
225 flowinfo |= htonl(uval) & IP6_FLOWINFO_FLOWLABEL;
226 flags &= ~IP6_TNL_F_USE_ORIG_FLOWLABEL;
227 }
228 } else if (strcmp(*argv, "dscp") == 0) {
229 NEXT_ARG();
230 if (strcmp(*argv, "inherit") != 0)
231 invarg("not inherit", *argv);
232 flags |= IP6_TNL_F_RCV_DSCP_COPY;
233 } else if (strcmp(*argv, "fwmark") == 0) {
234 NEXT_ARG();
235 if (strcmp(*argv, "inherit") != 0)
236 invarg("not inherit", *argv);
237 flags |= IP6_TNL_F_USE_ORIG_FWMARK;
238 } else
239 usage();
240 argc--, argv++;
241 }
242
243 addattr8(n, 1024, IFLA_IPTUN_PROTO, proto);
244 addattr_l(n, 1024, IFLA_IPTUN_LOCAL, &laddr, sizeof(laddr));
245 addattr_l(n, 1024, IFLA_IPTUN_REMOTE, &raddr, sizeof(raddr));
246 addattr8(n, 1024, IFLA_IPTUN_TTL, hop_limit);
247 addattr8(n, 1024, IFLA_IPTUN_ENCAP_LIMIT, encap_limit);
248 addattr32(n, 1024, IFLA_IPTUN_FLOWINFO, flowinfo);
249 addattr32(n, 1024, IFLA_IPTUN_FLAGS, flags);
250 addattr32(n, 1024, IFLA_IPTUN_LINK, link);
251
252 return 0;
253 }
254
ip6tunnel_print_opt(struct link_util * lu,FILE * f,struct rtattr * tb[])255 static void ip6tunnel_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
256 {
257 char s1[256];
258 char s2[64];
259 int flags = 0;
260 __u32 flowinfo = 0;
261
262 if (!tb)
263 return;
264
265 if (tb[IFLA_IPTUN_FLAGS])
266 flags = rta_getattr_u32(tb[IFLA_IPTUN_FLAGS]);
267
268 if (tb[IFLA_IPTUN_FLOWINFO])
269 flowinfo = rta_getattr_u32(tb[IFLA_IPTUN_FLOWINFO]);
270
271 if (tb[IFLA_IPTUN_PROTO]) {
272 switch (rta_getattr_u8(tb[IFLA_IPTUN_PROTO])) {
273 case IPPROTO_IPIP:
274 fprintf(f, "ipip6 ");
275 break;
276 case IPPROTO_IPV6:
277 fprintf(f, "ip6ip6 ");
278 break;
279 case 0:
280 fprintf(f, "any ");
281 break;
282 }
283 }
284
285 if (tb[IFLA_IPTUN_REMOTE]) {
286 fprintf(f, "remote %s ",
287 rt_addr_n2a(AF_INET6,
288 RTA_PAYLOAD(tb[IFLA_IPTUN_REMOTE]),
289 RTA_DATA(tb[IFLA_IPTUN_REMOTE]),
290 s1, sizeof(s1)));
291 }
292
293 if (tb[IFLA_IPTUN_LOCAL]) {
294 fprintf(f, "local %s ",
295 rt_addr_n2a(AF_INET6,
296 RTA_PAYLOAD(tb[IFLA_IPTUN_LOCAL]),
297 RTA_DATA(tb[IFLA_IPTUN_LOCAL]),
298 s1, sizeof(s1)));
299 }
300
301 if (tb[IFLA_IPTUN_LINK] && rta_getattr_u32(tb[IFLA_IPTUN_LINK])) {
302 unsigned link = rta_getattr_u32(tb[IFLA_IPTUN_LINK]);
303 const char *n = if_indextoname(link, s2);
304
305 if (n)
306 fprintf(f, "dev %s ", n);
307 else
308 fprintf(f, "dev %u ", link);
309 }
310
311 if (flags & IP6_TNL_F_IGN_ENCAP_LIMIT)
312 printf("encaplimit none ");
313 else if (tb[IFLA_IPTUN_ENCAP_LIMIT])
314 fprintf(f, "encaplimit %u ",
315 rta_getattr_u8(tb[IFLA_IPTUN_ENCAP_LIMIT]));
316
317 if (tb[IFLA_IPTUN_TTL])
318 fprintf(f, "hoplimit %u ", rta_getattr_u8(tb[IFLA_IPTUN_TTL]));
319
320 if (flags & IP6_TNL_F_USE_ORIG_TCLASS)
321 printf("tclass inherit ");
322 else if (tb[IFLA_IPTUN_FLOWINFO]) {
323 __u32 val = ntohl(flowinfo & IP6_FLOWINFO_TCLASS);
324
325 printf("tclass 0x%02x ", (__u8)(val >> 20));
326 }
327
328 if (flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
329 printf("flowlabel inherit ");
330 else
331 printf("flowlabel 0x%05x ", ntohl(flowinfo & IP6_FLOWINFO_FLOWLABEL));
332
333 printf("(flowinfo 0x%08x) ", ntohl(flowinfo));
334
335 if (flags & IP6_TNL_F_RCV_DSCP_COPY)
336 printf("dscp inherit ");
337
338 if (flags & IP6_TNL_F_MIP6_DEV)
339 fprintf(f, "mip6 ");
340
341 if (flags & IP6_TNL_F_USE_ORIG_FWMARK)
342 fprintf(f, "fwmark inherit ");
343 }
344
ip6tunnel_print_help(struct link_util * lu,int argc,char ** argv,FILE * f)345 static void ip6tunnel_print_help(struct link_util *lu, int argc, char **argv,
346 FILE *f)
347 {
348 print_usage(f);
349 }
350
351 struct link_util ip6tnl_link_util = {
352 .id = "ip6tnl",
353 .maxattr = IFLA_IPTUN_MAX,
354 .parse_opt = ip6tunnel_parse_opt,
355 .print_opt = ip6tunnel_print_opt,
356 .print_help = ip6tunnel_print_help,
357 };
358