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
16 #include <netinet/in.h>
17 #include <netinet/ip.h>
18 #include <arpa/inet.h>
19
20 #include "ip_common.h" /* #include "libbb.h" is inside */
21 #include "rt_names.h"
22 #include "utils.h"
23
24 /*
25 static void usage(void) __attribute__((noreturn));
26
27 static void usage(void)
28 {
29 fprintf(stderr, "Usage: ip rule [ list | add | del ] SELECTOR ACTION\n");
30 fprintf(stderr, "SELECTOR := [ from PREFIX ] [ to PREFIX ] [ tos TOS ] [ fwmark FWMARK ]\n");
31 fprintf(stderr, " [ dev STRING ] [ pref NUMBER ]\n");
32 fprintf(stderr, "ACTION := [ table TABLE_ID ] [ nat ADDRESS ]\n");
33 fprintf(stderr, " [ prohibit | reject | unreachable ]\n");
34 fprintf(stderr, " [ realms [SRCREALM/]DSTREALM ]\n");
35 fprintf(stderr, "TABLE_ID := [ local | main | default | NUMBER ]\n");
36 exit(-1);
37 }
38 */
39
print_rule(const struct sockaddr_nl * who UNUSED_PARAM,struct nlmsghdr * n,void * arg UNUSED_PARAM)40 static int FAST_FUNC print_rule(const struct sockaddr_nl *who UNUSED_PARAM,
41 struct nlmsghdr *n, void *arg UNUSED_PARAM)
42 {
43 struct rtmsg *r = NLMSG_DATA(n);
44 int len = n->nlmsg_len;
45 int host_len = -1;
46 struct rtattr * tb[RTA_MAX+1];
47
48 if (n->nlmsg_type != RTM_NEWRULE)
49 return 0;
50
51 len -= NLMSG_LENGTH(sizeof(*r));
52 if (len < 0)
53 return -1;
54
55 memset(tb, 0, sizeof(tb));
56 parse_rtattr(tb, RTA_MAX, RTM_RTA(r), len);
57
58 if (r->rtm_family == AF_INET)
59 host_len = 32;
60 else if (r->rtm_family == AF_INET6)
61 host_len = 128;
62 /* else if (r->rtm_family == AF_DECnet)
63 host_len = 16;
64 else if (r->rtm_family == AF_IPX)
65 host_len = 80;
66 */
67 printf("%u:\t", tb[RTA_PRIORITY] ?
68 *(unsigned*)RTA_DATA(tb[RTA_PRIORITY])
69 : 0);
70 printf("from ");
71 if (tb[RTA_SRC]) {
72 if (r->rtm_src_len != host_len) {
73 printf("%s/%u",
74 rt_addr_n2a(r->rtm_family, RTA_DATA(tb[RTA_SRC])),
75 r->rtm_src_len
76 );
77 } else {
78 fputs(format_host(r->rtm_family,
79 RTA_PAYLOAD(tb[RTA_SRC]),
80 RTA_DATA(tb[RTA_SRC])),
81 stdout
82 );
83 }
84 } else if (r->rtm_src_len) {
85 printf("0/%d", r->rtm_src_len);
86 } else {
87 printf("all");
88 }
89 bb_putchar(' ');
90
91 if (tb[RTA_DST]) {
92 if (r->rtm_dst_len != host_len) {
93 printf("to %s/%u ", rt_addr_n2a(r->rtm_family,
94 RTA_DATA(tb[RTA_DST])),
95 r->rtm_dst_len
96 );
97 } else {
98 printf("to %s ", format_host(r->rtm_family,
99 RTA_PAYLOAD(tb[RTA_DST]),
100 RTA_DATA(tb[RTA_DST])));
101 }
102 } else if (r->rtm_dst_len) {
103 printf("to 0/%d ", r->rtm_dst_len);
104 }
105
106 if (r->rtm_tos) {
107 printf("tos %s ", rtnl_dsfield_n2a(r->rtm_tos));
108 }
109 if (tb[RTA_PROTOINFO]) {
110 printf("fwmark %#x ", *(uint32_t*)RTA_DATA(tb[RTA_PROTOINFO]));
111 }
112
113 if (tb[RTA_IIF]) {
114 printf("iif %s ", (char*)RTA_DATA(tb[RTA_IIF]));
115 }
116
117 if (tb[RTA_TABLE])
118 printf("lookup %s ", rtnl_rttable_n2a(*(uint32_t*)RTA_DATA(tb[RTA_TABLE])));
119 else if (r->rtm_table)
120 printf("lookup %s ", rtnl_rttable_n2a(r->rtm_table));
121
122 if (tb[RTA_FLOW]) {
123 uint32_t to = *(uint32_t*)RTA_DATA(tb[RTA_FLOW]);
124 uint32_t from = to>>16;
125 to &= 0xFFFF;
126 if (from) {
127 printf("realms %s/",
128 rtnl_rtrealm_n2a(from));
129 }
130 printf("%s ",
131 rtnl_rtrealm_n2a(to));
132 }
133
134 if (r->rtm_type == RTN_NAT) {
135 if (tb[RTA_GATEWAY]) {
136 printf("map-to %s ",
137 format_host(r->rtm_family,
138 RTA_PAYLOAD(tb[RTA_GATEWAY]),
139 RTA_DATA(tb[RTA_GATEWAY]))
140 );
141 } else
142 printf("masquerade");
143 } else if (r->rtm_type != RTN_UNICAST)
144 fputs(rtnl_rtntype_n2a(r->rtm_type), stdout);
145
146 bb_putchar('\n');
147 /*fflush_all();*/
148 return 0;
149 }
150
151 /* Return value becomes exitcode. It's okay to not return at all */
iprule_list(char ** argv)152 static int iprule_list(char **argv)
153 {
154 struct rtnl_handle rth;
155 int af = preferred_family;
156
157 if (af == AF_UNSPEC)
158 af = AF_INET;
159
160 if (*argv) {
161 //bb_error_msg("\"rule show\" needs no arguments");
162 bb_warn_ignoring_args(*argv);
163 return -1;
164 }
165
166 xrtnl_open(&rth);
167
168 xrtnl_wilddump_request(&rth, af, RTM_GETRULE);
169 xrtnl_dump_filter(&rth, print_rule, NULL);
170
171 return 0;
172 }
173
174 /* Return value becomes exitcode. It's okay to not return at all */
iprule_modify(int cmd,char ** argv)175 static int iprule_modify(int cmd, char **argv)
176 {
177 static const char keywords[] ALIGN1 =
178 "from\0""to\0""preference\0""order\0""priority\0"
179 "tos\0""fwmark\0""realms\0""table\0""lookup\0""dev\0"
180 "iif\0""nat\0""map-to\0""type\0""help\0";
181 enum {
182 ARG_from = 1, ARG_to, ARG_preference, ARG_order, ARG_priority,
183 ARG_tos, ARG_fwmark, ARG_realms, ARG_table, ARG_lookup, ARG_dev,
184 ARG_iif, ARG_nat, ARG_map_to, ARG_type, ARG_help
185 };
186 bool table_ok = 0;
187 struct rtnl_handle rth;
188 struct {
189 struct nlmsghdr n;
190 struct rtmsg r;
191 char buf[1024];
192 } req;
193 smalluint key;
194
195 memset(&req, 0, sizeof(req));
196
197 req.n.nlmsg_type = cmd;
198 req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
199 req.n.nlmsg_flags = NLM_F_REQUEST;
200 req.r.rtm_family = preferred_family;
201 req.r.rtm_protocol = RTPROT_BOOT;
202 if (RT_SCOPE_UNIVERSE != 0)
203 req.r.rtm_scope = RT_SCOPE_UNIVERSE;
204 /*req.r.rtm_table = 0; - already is */
205 if (RTN_UNSPEC != 0)
206 req.r.rtm_type = RTN_UNSPEC;
207
208 if (cmd == RTM_NEWRULE) {
209 req.n.nlmsg_flags |= NLM_F_CREATE|NLM_F_EXCL;
210 req.r.rtm_type = RTN_UNICAST;
211 }
212
213 while (*argv) {
214 key = index_in_substrings(keywords, *argv) + 1;
215 if (key == 0) /* no match found in keywords array, bail out. */
216 invarg_1_to_2(*argv, applet_name);
217 if (key == ARG_from) {
218 inet_prefix dst;
219 NEXT_ARG();
220 get_prefix(&dst, *argv, req.r.rtm_family);
221 req.r.rtm_src_len = dst.bitlen;
222 addattr_l(&req.n, sizeof(req), RTA_SRC, &dst.data, dst.bytelen);
223 } else if (key == ARG_to) {
224 inet_prefix dst;
225 NEXT_ARG();
226 get_prefix(&dst, *argv, req.r.rtm_family);
227 req.r.rtm_dst_len = dst.bitlen;
228 addattr_l(&req.n, sizeof(req), RTA_DST, &dst.data, dst.bytelen);
229 } else if (key == ARG_preference ||
230 key == ARG_order ||
231 key == ARG_priority
232 ) {
233 uint32_t pref;
234 NEXT_ARG();
235 pref = get_u32(*argv, "preference");
236 addattr32(&req.n, sizeof(req), RTA_PRIORITY, pref);
237 } else if (key == ARG_tos) {
238 uint32_t tos;
239 NEXT_ARG();
240 if (rtnl_dsfield_a2n(&tos, *argv))
241 invarg_1_to_2(*argv, "TOS");
242 req.r.rtm_tos = tos;
243 } else if (key == ARG_fwmark) {
244 uint32_t fwmark;
245 NEXT_ARG();
246 fwmark = get_u32(*argv, "fwmark");
247 addattr32(&req.n, sizeof(req), RTA_PROTOINFO, fwmark);
248 } else if (key == ARG_realms) {
249 uint32_t realm;
250 NEXT_ARG();
251 if (get_rt_realms(&realm, *argv))
252 invarg_1_to_2(*argv, "realms");
253 addattr32(&req.n, sizeof(req), RTA_FLOW, realm);
254 } else if (key == ARG_table ||
255 key == ARG_lookup
256 ) {
257 uint32_t tid;
258 NEXT_ARG();
259 if (rtnl_rttable_a2n(&tid, *argv))
260 invarg_1_to_2(*argv, "table ID");
261 if (tid < 256)
262 req.r.rtm_table = tid;
263 else {
264 req.r.rtm_table = RT_TABLE_UNSPEC;
265 addattr32(&req.n, sizeof(req), RTA_TABLE, tid);
266 }
267 table_ok = 1;
268 } else if (key == ARG_dev ||
269 key == ARG_iif
270 ) {
271 NEXT_ARG();
272 addattr_l(&req.n, sizeof(req), RTA_IIF, *argv, strlen(*argv)+1);
273 } else if (key == ARG_nat ||
274 key == ARG_map_to
275 ) {
276 NEXT_ARG();
277 addattr32(&req.n, sizeof(req), RTA_GATEWAY, get_addr32(*argv));
278 req.r.rtm_type = RTN_NAT;
279 } else {
280 int type;
281
282 if (key == ARG_type) {
283 NEXT_ARG();
284 }
285 if (key == ARG_help)
286 bb_show_usage();
287 if (rtnl_rtntype_a2n(&type, *argv))
288 invarg_1_to_2(*argv, "type");
289 req.r.rtm_type = type;
290 }
291 argv++;
292 }
293
294 if (req.r.rtm_family == AF_UNSPEC)
295 req.r.rtm_family = AF_INET;
296
297 if (!table_ok && cmd == RTM_NEWRULE)
298 req.r.rtm_table = RT_TABLE_MAIN;
299
300 xrtnl_open(&rth);
301
302 if (rtnl_talk(&rth, &req.n, 0, 0, NULL, NULL, NULL) < 0)
303 return 2;
304
305 return 0;
306 }
307
308 /* Return value becomes exitcode. It's okay to not return at all */
do_iprule(char ** argv)309 int FAST_FUNC do_iprule(char **argv)
310 {
311 static const char ip_rule_commands[] ALIGN1 =
312 "add\0""delete\0""list\0""show\0";
313 if (*argv) {
314 int cmd = index_in_substrings(ip_rule_commands, *argv);
315 if (cmd < 0)
316 invarg_1_to_2(*argv, applet_name);
317 argv++;
318 if (cmd < 2)
319 return iprule_modify((cmd == 0) ? RTM_NEWRULE : RTM_DELRULE, argv);
320 }
321 return iprule_list(argv);
322 }
323