1 /* vi: set sw=4 ts=4: */
2 /*
3 * This program is free software; you can redistribute it and/or
4 * modify it under the terms of the GNU General Public License
5 * as published by the Free Software Foundation; either version
6 * 2 of the License, or (at your option) any later version.
7 *
8 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
9 *
10 * Changes:
11 *
12 * Rani Assaf <rani@magic.metawire.com> 980929: resolve addresses
13 * initially integrated into busybox by Bernhard Reutner-Fischer
14 */
15 #include <netinet/in.h>
16 #include <netinet/ip.h>
17 #include <arpa/inet.h>
18
19 /* from <linux/fib_rules.h>: */
20 #define FRA_FWMARK 10
21 #define FRA_SUPPRESS_IFGROUP 13
22 #define FRA_SUPPRESS_PREFIXLEN 14
23 #define FRA_FWMASK 16
24
25 #include "ip_common.h" /* #include "libbb.h" is inside */
26 #include "rt_names.h"
27 #include "utils.h"
28
29 #include <linux/version.h>
30 /* RTA_TABLE is not a define, can't test with ifdef. */
31 /* As a proxy, test which kernels toolchain expects: */
32 #define HAVE_RTA_TABLE (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,19))
33
34 /* If you add stuff here, update iprule_full_usage */
35 static const char keywords[] ALIGN1 =
36 "from\0""to\0""preference\0""order\0""priority\0"
37 "tos\0""fwmark\0""realms\0""table\0""lookup\0"
38 "suppress_prefixlength\0""suppress_ifgroup\0"
39 "dev\0""iif\0""nat\0""map-to\0""type\0""help\0"
40 ;
41 #define keyword_preference (keywords + sizeof("from") + sizeof("to"))
42 #define keyword_fwmark (keyword_preference + sizeof("preference") + sizeof("order") + sizeof("priority") + sizeof("tos"))
43 #define keyword_realms (keyword_fwmark + sizeof("fwmark"))
44 #define keyword_suppress_prefixlength (keyword_realms + sizeof("realms") + sizeof("table") + sizeof("lookup"))
45 #define keyword_suppress_ifgroup (keyword_suppress_prefixlength + sizeof("suppress_prefixlength"))
46 enum {
47 ARG_from = 1, ARG_to, ARG_preference, ARG_order, ARG_priority,
48 ARG_tos, ARG_fwmark, ARG_realms, ARG_table, ARG_lookup,
49 ARG_suppress_prefixlength, ARG_suppress_ifgroup,
50 ARG_dev, ARG_iif, ARG_nat, ARG_map_to, ARG_type, ARG_help,
51 };
52
print_rule(const struct sockaddr_nl * who UNUSED_PARAM,struct nlmsghdr * n,void * arg UNUSED_PARAM)53 static int FAST_FUNC print_rule(const struct sockaddr_nl *who UNUSED_PARAM,
54 struct nlmsghdr *n, void *arg UNUSED_PARAM)
55 {
56 struct rtmsg *r = NLMSG_DATA(n);
57 int len = n->nlmsg_len;
58 int host_len = -1;
59 struct rtattr * tb[RTA_MAX+1];
60
61 if (n->nlmsg_type != RTM_NEWRULE)
62 return 0;
63
64 len -= NLMSG_LENGTH(sizeof(*r));
65 if (len < 0)
66 return -1;
67
68 //memset(tb, 0, sizeof(tb)); - parse_rtattr does this
69 parse_rtattr(tb, RTA_MAX, RTM_RTA(r), len);
70
71 if (r->rtm_family == AF_INET)
72 host_len = 32;
73 else if (r->rtm_family == AF_INET6)
74 host_len = 128;
75 /* else if (r->rtm_family == AF_DECnet)
76 host_len = 16;
77 else if (r->rtm_family == AF_IPX)
78 host_len = 80;
79 */
80 printf("%u:\t", tb[RTA_PRIORITY] ?
81 *(unsigned*)RTA_DATA(tb[RTA_PRIORITY])
82 : 0);
83 printf("from ");
84 if (tb[RTA_SRC]) {
85 if (r->rtm_src_len != host_len) {
86 printf("%s/%u",
87 rt_addr_n2a(r->rtm_family, RTA_DATA(tb[RTA_SRC])),
88 r->rtm_src_len
89 );
90 } else {
91 fputs_stdout(format_host(r->rtm_family,
92 RTA_PAYLOAD(tb[RTA_SRC]),
93 RTA_DATA(tb[RTA_SRC]))
94 );
95 }
96 } else if (r->rtm_src_len) {
97 printf("0/%d", r->rtm_src_len);
98 } else {
99 printf("all");
100 }
101 bb_putchar(' ');
102
103 if (tb[RTA_DST]) {
104 if (r->rtm_dst_len != host_len) {
105 printf("to %s/%u ", rt_addr_n2a(r->rtm_family,
106 RTA_DATA(tb[RTA_DST])),
107 r->rtm_dst_len
108 );
109 } else {
110 printf("to %s ", format_host(r->rtm_family,
111 RTA_PAYLOAD(tb[RTA_DST]),
112 RTA_DATA(tb[RTA_DST])));
113 }
114 } else if (r->rtm_dst_len) {
115 printf("to 0/%d ", r->rtm_dst_len);
116 }
117
118 if (r->rtm_tos) {
119 printf("tos %s ", rtnl_dsfield_n2a(r->rtm_tos));
120 }
121
122 if (tb[FRA_FWMARK] || tb[FRA_FWMASK]) {
123 uint32_t mark = 0, mask = 0;
124
125 if (tb[FRA_FWMARK])
126 mark = *(uint32_t*)RTA_DATA(tb[FRA_FWMARK]);
127 if (tb[FRA_FWMASK]
128 && (mask = *(uint32_t*)RTA_DATA(tb[FRA_FWMASK])) != 0xFFFFFFFF
129 )
130 printf("fwmark %#x/%#x ", mark, mask);
131 else
132 printf("fwmark %#x ", mark);
133 }
134
135 if (tb[RTA_IIF]) {
136 printf("iif %s ", (char*)RTA_DATA(tb[RTA_IIF]));
137 }
138
139 #if HAVE_RTA_TABLE
140 if (tb[RTA_TABLE])
141 printf("lookup %s ", rtnl_rttable_n2a(*(uint32_t*)RTA_DATA(tb[RTA_TABLE])));
142 else
143 #endif
144 if (r->rtm_table)
145 printf("lookup %s ", rtnl_rttable_n2a(r->rtm_table));
146
147 if (tb[FRA_SUPPRESS_PREFIXLEN]) {
148 int pl = *(uint32_t*)RTA_DATA(tb[FRA_SUPPRESS_PREFIXLEN]);
149 if (pl != -1)
150 printf("%s %d ", keyword_suppress_prefixlength, pl);
151 }
152 if (tb[FRA_SUPPRESS_IFGROUP]) {
153 int grp = *(uint32_t*)RTA_DATA(tb[FRA_SUPPRESS_IFGROUP]);
154 if (grp != -1)
155 printf("%s %d ", keyword_suppress_ifgroup, grp);
156 }
157
158 if (tb[RTA_FLOW]) {
159 uint32_t to = *(uint32_t*)RTA_DATA(tb[RTA_FLOW]);
160 uint32_t from = to>>16;
161 to &= 0xFFFF;
162 if (from) {
163 printf("realms %s/",
164 rtnl_rtrealm_n2a(from));
165 }
166 printf("%s ",
167 rtnl_rtrealm_n2a(to));
168 }
169
170 if (r->rtm_type == RTN_NAT) {
171 if (tb[RTA_GATEWAY]) {
172 printf("map-to %s ",
173 format_host(r->rtm_family,
174 RTA_PAYLOAD(tb[RTA_GATEWAY]),
175 RTA_DATA(tb[RTA_GATEWAY]))
176 );
177 } else
178 printf("masquerade");
179 } else if (r->rtm_type != RTN_UNICAST)
180 fputs_stdout(rtnl_rtntype_n2a(r->rtm_type));
181
182 bb_putchar('\n');
183 /*fflush_all();*/
184 return 0;
185 }
186
187 /* Return value becomes exitcode. It's okay to not return at all */
iprule_list(char ** argv)188 static int iprule_list(char **argv)
189 {
190 struct rtnl_handle rth;
191 int af = preferred_family;
192
193 if (af == AF_UNSPEC)
194 af = AF_INET;
195
196 if (*argv) {
197 //bb_error_msg("\"rule show\" needs no arguments");
198 bb_warn_ignoring_args(*argv);
199 return -1;
200 }
201
202 xrtnl_open(&rth);
203
204 xrtnl_wilddump_request(&rth, af, RTM_GETRULE);
205 xrtnl_dump_filter(&rth, print_rule, NULL);
206
207 return 0;
208 }
209
210 /* Return value becomes exitcode. It's okay to not return at all */
iprule_modify(int cmd,char ** argv)211 static int iprule_modify(int cmd, char **argv)
212 {
213 bool table_ok = 0;
214 struct rtnl_handle rth;
215 struct {
216 struct nlmsghdr n;
217 struct rtmsg r;
218 char buf[1024];
219 } req;
220 smalluint key;
221
222 memset(&req, 0, sizeof(req));
223
224 req.n.nlmsg_type = cmd;
225 req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
226 req.n.nlmsg_flags = NLM_F_REQUEST;
227 req.r.rtm_family = preferred_family;
228 req.r.rtm_protocol = RTPROT_BOOT;
229 if (RT_SCOPE_UNIVERSE != 0)
230 req.r.rtm_scope = RT_SCOPE_UNIVERSE;
231 /*req.r.rtm_table = 0; - already is */
232 if (RTN_UNSPEC != 0)
233 req.r.rtm_type = RTN_UNSPEC;
234
235 if (cmd == RTM_NEWRULE) {
236 req.n.nlmsg_flags |= NLM_F_CREATE|NLM_F_EXCL;
237 req.r.rtm_type = RTN_UNICAST;
238 }
239
240 while (*argv) {
241 key = index_in_substrings(keywords, *argv) + 1;
242 if (key == 0) /* no match found in keywords array, bail out. */
243 invarg_1_to_2(*argv, applet_name);
244 if (key == ARG_from) {
245 inet_prefix dst;
246 NEXT_ARG();
247 get_prefix(&dst, *argv, req.r.rtm_family);
248 req.r.rtm_src_len = dst.bitlen;
249 addattr_l(&req.n, sizeof(req), RTA_SRC, &dst.data, dst.bytelen);
250 } else if (key == ARG_to) {
251 inet_prefix dst;
252 NEXT_ARG();
253 get_prefix(&dst, *argv, req.r.rtm_family);
254 req.r.rtm_dst_len = dst.bitlen;
255 addattr_l(&req.n, sizeof(req), RTA_DST, &dst.data, dst.bytelen);
256 } else if (key == ARG_preference ||
257 key == ARG_order ||
258 key == ARG_priority
259 ) {
260 uint32_t pref;
261 NEXT_ARG();
262 pref = get_u32(*argv, keyword_preference);
263 addattr32(&req.n, sizeof(req), RTA_PRIORITY, pref);
264 } else if (key == ARG_tos) {
265 uint32_t tos;
266 NEXT_ARG();
267 if (rtnl_dsfield_a2n(&tos, *argv))
268 invarg_1_to_2(*argv, "TOS");
269 req.r.rtm_tos = tos;
270 } else if (key == ARG_fwmark) {
271 char *slash;
272 uint32_t fwmark, fwmask;
273 NEXT_ARG();
274 slash = strchr(*argv, '/');
275 if (slash)
276 *slash = '\0';
277 fwmark = get_u32(*argv, keyword_fwmark);
278 addattr32(&req.n, sizeof(req), FRA_FWMARK, fwmark);
279 if (slash) {
280 fwmask = get_u32(slash + 1, "fwmask");
281 addattr32(&req.n, sizeof(req), FRA_FWMASK, fwmask);
282 }
283 } else if (key == ARG_realms) {
284 uint32_t realm;
285 NEXT_ARG();
286 if (get_rt_realms(&realm, *argv))
287 invarg_1_to_2(*argv, keyword_realms);
288 addattr32(&req.n, sizeof(req), RTA_FLOW, realm);
289 } else if (key == ARG_table ||
290 key == ARG_lookup
291 ) {
292 uint32_t tid;
293 NEXT_ARG();
294 if (rtnl_rttable_a2n(&tid, *argv))
295 invarg_1_to_2(*argv, "table ID");
296
297 #if HAVE_RTA_TABLE
298 if (tid > 255) {
299 req.r.rtm_table = RT_TABLE_UNSPEC;
300 addattr32(&req.n, sizeof(req), RTA_TABLE, tid);
301 } else
302 #endif
303 req.r.rtm_table = tid;
304
305 table_ok = 1;
306 } else if (key == ARG_suppress_prefixlength) {
307 int prefix_length;
308 NEXT_ARG();
309 prefix_length = get_u32(*argv, keyword_suppress_prefixlength);
310 addattr32(&req.n, sizeof(req), FRA_SUPPRESS_PREFIXLEN, prefix_length);
311 } else if (key == ARG_suppress_ifgroup) {
312 int grp;
313 NEXT_ARG();
314 grp = get_u32(*argv, keyword_suppress_ifgroup);
315 addattr32(&req.n, sizeof(req), FRA_SUPPRESS_IFGROUP, grp);
316 } else if (key == ARG_dev ||
317 key == ARG_iif
318 ) {
319 NEXT_ARG();
320 addattr_l(&req.n, sizeof(req), RTA_IIF, *argv, strlen(*argv)+1);
321 } else if (key == ARG_nat ||
322 key == ARG_map_to
323 ) {
324 NEXT_ARG();
325 addattr32(&req.n, sizeof(req), RTA_GATEWAY, get_addr32(*argv));
326 req.r.rtm_type = RTN_NAT;
327 } else {
328 int type;
329
330 if (key == ARG_type) {
331 NEXT_ARG();
332 }
333 if (key == ARG_help)
334 bb_show_usage();
335 if (rtnl_rtntype_a2n(&type, *argv))
336 invarg_1_to_2(*argv, "type");
337 req.r.rtm_type = type;
338 }
339 argv++;
340 }
341
342 if (req.r.rtm_family == AF_UNSPEC)
343 req.r.rtm_family = AF_INET;
344
345 if (!table_ok && cmd == RTM_NEWRULE)
346 req.r.rtm_table = RT_TABLE_MAIN;
347
348 xrtnl_open(&rth);
349
350 if (rtnl_talk(&rth, &req.n, 0, 0, NULL, NULL, NULL) < 0)
351 return 2;
352
353 return 0;
354 }
355
356 /* Return value becomes exitcode. It's okay to not return at all */
do_iprule(char ** argv)357 int FAST_FUNC do_iprule(char **argv)
358 {
359 static const char ip_rule_commands[] ALIGN1 =
360 "add\0""delete\0""list\0""show\0";
361 if (*argv) {
362 int cmd = index_in_substrings(ip_rule_commands, *argv);
363 if (cmd < 0)
364 invarg_1_to_2(*argv, applet_name);
365 argv++;
366 if (cmd < 2)
367 return iprule_modify((cmd == 0) ? RTM_NEWRULE : RTM_DELRULE, argv);
368 }
369 return iprule_list(argv);
370 }
371