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12#include <net/if.h>
13#include <net/if_packet.h>
14#include <netpacket/packet.h>
15#include <net/ethernet.h>
16
17#include "ip_common.h"
18#include "rt_names.h"
19#include "utils.h"
20
21
22#define SIOCSIFNAME 0x8923
23
24
25static int get_ctl_fd(void)
26{
27 int fd;
28
29 fd = socket(PF_INET, SOCK_DGRAM, 0);
30 if (fd >= 0)
31 return fd;
32 fd = socket(PF_PACKET, SOCK_DGRAM, 0);
33 if (fd >= 0)
34 return fd;
35 return xsocket(PF_INET6, SOCK_DGRAM, 0);
36}
37
38
39static void do_chflags(char *dev, uint32_t flags, uint32_t mask)
40{
41 struct ifreq ifr;
42 int fd;
43
44 strncpy_IFNAMSIZ(ifr.ifr_name, dev);
45 fd = get_ctl_fd();
46 xioctl(fd, SIOCGIFFLAGS, &ifr);
47 if ((ifr.ifr_flags ^ flags) & mask) {
48 ifr.ifr_flags &= ~mask;
49 ifr.ifr_flags |= mask & flags;
50 xioctl(fd, SIOCSIFFLAGS, &ifr);
51 }
52 close(fd);
53}
54
55
56static void do_changename(char *dev, char *newdev)
57{
58 struct ifreq ifr;
59 int fd;
60
61 strncpy_IFNAMSIZ(ifr.ifr_name, dev);
62 strncpy_IFNAMSIZ(ifr.ifr_newname, newdev);
63 fd = get_ctl_fd();
64 xioctl(fd, SIOCSIFNAME, &ifr);
65 close(fd);
66}
67
68
69static void set_qlen(char *dev, int qlen)
70{
71 struct ifreq ifr;
72 int s;
73
74 s = get_ctl_fd();
75 memset(&ifr, 0, sizeof(ifr));
76 strncpy_IFNAMSIZ(ifr.ifr_name, dev);
77 ifr.ifr_qlen = qlen;
78 xioctl(s, SIOCSIFTXQLEN, &ifr);
79 close(s);
80}
81
82
83static void set_mtu(char *dev, int mtu)
84{
85 struct ifreq ifr;
86 int s;
87
88 s = get_ctl_fd();
89 memset(&ifr, 0, sizeof(ifr));
90 strncpy_IFNAMSIZ(ifr.ifr_name, dev);
91 ifr.ifr_mtu = mtu;
92 xioctl(s, SIOCSIFMTU, &ifr);
93 close(s);
94}
95
96
97static int get_address(char *dev, int *htype)
98{
99 struct ifreq ifr;
100 struct sockaddr_ll me;
101 socklen_t alen;
102 int s;
103
104 s = xsocket(PF_PACKET, SOCK_DGRAM, 0);
105
106 memset(&ifr, 0, sizeof(ifr));
107 strncpy_IFNAMSIZ(ifr.ifr_name, dev);
108 xioctl(s, SIOCGIFINDEX, &ifr);
109
110 memset(&me, 0, sizeof(me));
111 me.sll_family = AF_PACKET;
112 me.sll_ifindex = ifr.ifr_ifindex;
113 me.sll_protocol = htons(ETH_P_LOOP);
114 xbind(s, (struct sockaddr*)&me, sizeof(me));
115
116 alen = sizeof(me);
117 if (getsockname(s, (struct sockaddr*)&me, &alen) == -1) {
118 bb_perror_msg_and_die("getsockname");
119 }
120 close(s);
121 *htype = me.sll_hatype;
122 return me.sll_halen;
123}
124
125
126static void parse_address(char *dev, int hatype, int halen, char *lla, struct ifreq *ifr)
127{
128 int alen;
129
130 memset(ifr, 0, sizeof(*ifr));
131 strncpy_IFNAMSIZ(ifr->ifr_name, dev);
132 ifr->ifr_hwaddr.sa_family = hatype;
133
134 alen = hatype == 1 ? 14 : 19;
135 alen = ll_addr_a2n((unsigned char *)(ifr->ifr_hwaddr.sa_data), alen, lla);
136 if (alen < 0)
137 exit(EXIT_FAILURE);
138 if (alen != halen) {
139 bb_error_msg_and_die("wrong address (%s) length: expected %d bytes", lla, halen);
140 }
141}
142
143
144static void set_address(struct ifreq *ifr, int brd)
145{
146 int s;
147
148 s = get_ctl_fd();
149 if (brd)
150 xioctl(s, SIOCSIFHWBROADCAST, ifr);
151 else
152 xioctl(s, SIOCSIFHWADDR, ifr);
153 close(s);
154}
155
156
157static void die_must_be_on_off(const char *msg) NORETURN;
158static void die_must_be_on_off(const char *msg)
159{
160 bb_error_msg_and_die("argument of \"%s\" must be \"on\" or \"off\"", msg);
161}
162
163
164static int do_set(char **argv)
165{
166 char *dev = NULL;
167 uint32_t mask = 0;
168 uint32_t flags = 0;
169 int qlen = -1;
170 int mtu = -1;
171 char *newaddr = NULL;
172 char *newbrd = NULL;
173 struct ifreq ifr0, ifr1;
174 char *newname = NULL;
175 int htype, halen;
176 static const char keywords[] ALIGN1 =
177 "up\0""down\0""name\0""mtu\0""multicast\0"
178 "arp\0""address\0""dev\0";
179 enum { ARG_up = 0, ARG_down, ARG_name, ARG_mtu, ARG_multicast,
180 ARG_arp, ARG_addr, ARG_dev };
181 static const char str_on_off[] ALIGN1 = "on\0""off\0";
182 enum { PARM_on = 0, PARM_off };
183 smalluint key;
184
185 while (*argv) {
186
187
188 key = index_in_substrings(keywords, *argv);
189 if (key == ARG_up) {
190 mask |= IFF_UP;
191 flags |= IFF_UP;
192 }
193 if (key == ARG_down) {
194 mask |= IFF_UP;
195 flags &= ~IFF_UP;
196 }
197 if (key == ARG_name) {
198 NEXT_ARG();
199 newname = *argv;
200 }
201 if (key == ARG_mtu) {
202 NEXT_ARG();
203 if (mtu != -1)
204 duparg("mtu", *argv);
205 mtu = get_unsigned(*argv, "mtu");
206 }
207 if (key == ARG_multicast) {
208 int param;
209 NEXT_ARG();
210 mask |= IFF_MULTICAST;
211 param = index_in_strings(str_on_off, *argv);
212 if (param < 0)
213 die_must_be_on_off("multicast");
214 if (param == PARM_on)
215 flags |= IFF_MULTICAST;
216 else
217 flags &= ~IFF_MULTICAST;
218 }
219 if (key == ARG_arp) {
220 int param;
221 NEXT_ARG();
222 mask |= IFF_NOARP;
223 param = index_in_strings(str_on_off, *argv);
224 if (param < 0)
225 die_must_be_on_off("arp");
226 if (param == PARM_on)
227 flags &= ~IFF_NOARP;
228 else
229 flags |= IFF_NOARP;
230 }
231 if (key == ARG_addr) {
232 NEXT_ARG();
233 newaddr = *argv;
234 }
235 if (key >= ARG_dev) {
236 if (key == ARG_dev) {
237 NEXT_ARG();
238 }
239 if (dev)
240 duparg2("dev", *argv);
241 dev = *argv;
242 }
243 argv++;
244 }
245
246 if (!dev) {
247 bb_error_msg_and_die(bb_msg_requires_arg, "\"dev\"");
248 }
249
250 if (newaddr || newbrd) {
251 halen = get_address(dev, &htype);
252 if (newaddr) {
253 parse_address(dev, htype, halen, newaddr, &ifr0);
254 }
255 if (newbrd) {
256 parse_address(dev, htype, halen, newbrd, &ifr1);
257 }
258 }
259
260 if (newname && strcmp(dev, newname)) {
261 do_changename(dev, newname);
262 dev = newname;
263 }
264 if (qlen != -1) {
265 set_qlen(dev, qlen);
266 }
267 if (mtu != -1) {
268 set_mtu(dev, mtu);
269 }
270 if (newaddr || newbrd) {
271 if (newbrd) {
272 set_address(&ifr1, 1);
273 }
274 if (newaddr) {
275 set_address(&ifr0, 0);
276 }
277 }
278 if (mask)
279 do_chflags(dev, flags, mask);
280 return 0;
281}
282
283static int ipaddr_list_link(char **argv)
284{
285 preferred_family = AF_PACKET;
286 return ipaddr_list_or_flush(argv, 0);
287}
288
289
290int do_iplink(char **argv)
291{
292 static const char keywords[] ALIGN1 =
293 "set\0""show\0""lst\0""list\0";
294 int key;
295 if (!*argv)
296 return ipaddr_list_link(argv);
297 key = index_in_substrings(keywords, *argv);
298 if (key < 0)
299 bb_error_msg_and_die(bb_msg_invalid_arg, *argv, applet_name);
300 argv++;
301 if (key == 0)
302 return do_set(argv);
303
304 return ipaddr_list_link(argv);
305}
306
