1 /*-
2 * Copyright (c) 2015 Dmitry Chagin <dchagin@FreeBSD.org>
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23 * SUCH DAMAGE.
24 */
25
26 #include <sys/param.h>
27 #include <sys/systm.h>
28 #include <sys/kernel.h>
29 #include <sys/ctype.h>
30 #include <sys/eventhandler.h>
31 #include <sys/jail.h>
32 #include <sys/socket.h>
33 #include <sys/sysctl.h>
34 #include <net/if.h>
35 #include <net/if_dl.h>
36 #include <net/if_types.h>
37 #include <net/if_var.h>
38 #include <net/if_private.h>
39 #include <net/vnet.h>
40
41 #include <compat/linux/linux.h>
42 #include <compat/linux/linux_common.h>
43 #include <compat/linux/linux_mib.h>
44
45 _Static_assert(LINUX_IFNAMSIZ == IFNAMSIZ, "Linux IFNAMSIZ");
46
47 static bool use_real_ifnames = false;
48 SYSCTL_BOOL(_compat_linux, OID_AUTO, use_real_ifnames, CTLFLAG_RWTUN,
49 &use_real_ifnames, 0,
50 "Use FreeBSD interface names instead of generating ethN aliases");
51
52 VNET_DEFINE_STATIC(struct unrhdr *, linux_eth_unr);
53 #define V_linux_eth_unr VNET(linux_eth_unr)
54
55 static eventhandler_tag ifnet_arrival_tag;
56 static eventhandler_tag ifnet_departure_tag;
57
58 static void
linux_ifnet_arrival(void * arg __unused,struct ifnet * ifp)59 linux_ifnet_arrival(void *arg __unused, struct ifnet *ifp)
60 {
61 if (ifp->if_type == IFT_ETHER)
62 ifp->if_linux_ethno = alloc_unr(V_linux_eth_unr);
63 }
64
65 static void
linux_ifnet_departure(void * arg __unused,struct ifnet * ifp)66 linux_ifnet_departure(void *arg __unused, struct ifnet *ifp)
67 {
68 if (ifp->if_type == IFT_ETHER)
69 free_unr(V_linux_eth_unr, ifp->if_linux_ethno);
70 }
71
72 void
linux_ifnet_init(void)73 linux_ifnet_init(void)
74 {
75 ifnet_arrival_tag = EVENTHANDLER_REGISTER(ifnet_arrival_event,
76 linux_ifnet_arrival, NULL, EVENTHANDLER_PRI_FIRST);
77 ifnet_departure_tag = EVENTHANDLER_REGISTER(ifnet_departure_event,
78 linux_ifnet_departure, NULL, EVENTHANDLER_PRI_LAST);
79 }
80
81 void
linux_ifnet_uninit(void)82 linux_ifnet_uninit(void)
83 {
84 EVENTHANDLER_DEREGISTER(ifnet_arrival_event, ifnet_arrival_tag);
85 EVENTHANDLER_DEREGISTER(ifnet_departure_event, ifnet_departure_tag);
86 }
87
88 static void
linux_ifnet_vnet_init(void * arg __unused)89 linux_ifnet_vnet_init(void *arg __unused)
90 {
91 struct epoch_tracker et;
92 struct if_iter it;
93 if_t ifp;
94
95 V_linux_eth_unr = new_unrhdr(0, INT_MAX, NULL);
96 NET_EPOCH_ENTER(et);
97 for (ifp = if_iter_start(&it); ifp != NULL; ifp = if_iter_next(&it))
98 linux_ifnet_arrival(NULL, ifp);
99 NET_EPOCH_EXIT(et);
100 }
101 VNET_SYSINIT(linux_ifnet_vnet_init, SI_SUB_PROTO_IF, SI_ORDER_ANY,
102 linux_ifnet_vnet_init, NULL);
103
104 static void
linux_ifnet_vnet_uninit(void * arg __unused)105 linux_ifnet_vnet_uninit(void *arg __unused)
106 {
107 /*
108 * At a normal vnet shutdown all interfaces are gone at this point.
109 * But when we kldunload linux.ko, the vnet_deregister_sysuninit()
110 * would call this function for the default vnet.
111 */
112 if (IS_DEFAULT_VNET(curvnet))
113 clear_unrhdr(V_linux_eth_unr);
114 delete_unrhdr(V_linux_eth_unr);
115 }
116 VNET_SYSUNINIT(linux_ifnet_vnet_uninit, SI_SUB_PROTO_IF, SI_ORDER_ANY,
117 linux_ifnet_vnet_uninit, NULL);
118
119 /*
120 * Translate a FreeBSD interface name to a Linux interface name
121 * by interface index, and return the number of bytes copied to lxname.
122 */
123 int
ifname_bsd_to_linux_idx(u_int idx,char * lxname,size_t len)124 ifname_bsd_to_linux_idx(u_int idx, char *lxname, size_t len)
125 {
126 struct epoch_tracker et;
127 struct ifnet *ifp;
128 int ret;
129
130 ret = 0;
131 CURVNET_SET(TD_TO_VNET(curthread));
132 NET_EPOCH_ENTER(et);
133 ifp = ifnet_byindex(idx);
134 if (ifp != NULL)
135 ret = ifname_bsd_to_linux_ifp(ifp, lxname, len);
136 NET_EPOCH_EXIT(et);
137 CURVNET_RESTORE();
138 return (ret);
139 }
140
141 /*
142 * Translate a FreeBSD interface name to a Linux interface name,
143 * and return the number of bytes copied to lxname, 0 if interface
144 * not found, -1 on error.
145 */
146 int
ifname_bsd_to_linux_ifp(const struct ifnet * ifp,char * lxname,size_t len)147 ifname_bsd_to_linux_ifp(const struct ifnet *ifp, char *lxname, size_t len)
148 {
149 /*
150 * Linux loopback interface name is lo (not lo0),
151 * we translate lo to lo0, loX to loX.
152 */
153 if (ifp->if_type == IFT_LOOP &&
154 strncmp(ifp->if_xname, "lo0", IFNAMSIZ) == 0)
155 return (strlcpy(lxname, "lo", len));
156
157 /* Short-circuit non ethernet interfaces. */
158 if (ifp->if_type != IFT_ETHER || use_real_ifnames)
159 return (strlcpy(lxname, ifp->if_xname, len));
160
161 /* Determine the (relative) unit number for ethernet interfaces. */
162 return (snprintf(lxname, len, "eth%d", ifp->if_linux_ethno));
163 }
164
165 /*
166 * Translate a Linux interface name to a FreeBSD interface name,
167 * and return the associated ifnet structure
168 * bsdname and lxname need to be least IFNAMSIZ bytes long, but
169 * can point to the same buffer.
170 */
171 struct ifname_linux_to_ifp_cb_s {
172 bool is_lo;
173 bool is_eth;
174 int unit;
175 const char *lxname;
176 if_t ifp;
177 };
178
179 static int
ifname_linux_to_ifp_cb(if_t ifp,void * arg)180 ifname_linux_to_ifp_cb(if_t ifp, void *arg)
181 {
182 struct ifname_linux_to_ifp_cb_s *cbs = arg;
183
184 NET_EPOCH_ASSERT();
185
186 /*
187 * Allow Linux programs to use FreeBSD names. Don't presume
188 * we never have an interface named "eth", so don't make
189 * the test optional based on is_eth.
190 */
191 if (strncmp(if_name(ifp), cbs->lxname, LINUX_IFNAMSIZ) == 0)
192 goto out;
193 if (cbs->is_eth && ifp->if_type == IFT_ETHER &&
194 ifp->if_linux_ethno == cbs->unit)
195 goto out;
196 if (cbs->is_lo && ifp->if_type == IFT_LOOP)
197 goto out;
198 return (0);
199
200 out:
201 cbs->ifp = ifp;
202 return (1);
203 }
204
205 struct ifnet *
ifname_linux_to_ifp(const char * lxname)206 ifname_linux_to_ifp(const char *lxname)
207 {
208 struct ifname_linux_to_ifp_cb_s arg = {
209 .lxname = lxname,
210 };
211 int len;
212 char *ep;
213
214 NET_EPOCH_ASSERT();
215
216 for (len = 0; len < LINUX_IFNAMSIZ; ++len)
217 if (!isalpha(lxname[len]) || lxname[len] == '\0')
218 break;
219 if (len == 0 || len == LINUX_IFNAMSIZ)
220 return (NULL);
221 /*
222 * Linux loopback interface name is lo (not lo0),
223 * we translate lo to lo0, loX to loX.
224 */
225 arg.is_lo = (len == 2 && strncmp(lxname, "lo", LINUX_IFNAMSIZ) == 0);
226 arg.unit = (int)strtoul(lxname + len, &ep, 10);
227 if ((ep == NULL || ep == lxname + len || ep >= lxname + LINUX_IFNAMSIZ) &&
228 arg.is_lo == 0)
229 return (NULL);
230 arg.is_eth = (len == 3 && strncmp(lxname, "eth", len) == 0);
231
232 if_foreach(ifname_linux_to_ifp_cb, &arg);
233 return (arg.ifp);
234 }
235
236 int
ifname_linux_to_bsd(struct thread * td,const char * lxname,char * bsdname)237 ifname_linux_to_bsd(struct thread *td, const char *lxname, char *bsdname)
238 {
239 struct epoch_tracker et;
240 struct ifnet *ifp;
241
242 CURVNET_SET(TD_TO_VNET(td));
243 NET_EPOCH_ENTER(et);
244 ifp = ifname_linux_to_ifp(lxname);
245 if (ifp != NULL && bsdname != NULL)
246 strlcpy(bsdname, if_name(ifp), IFNAMSIZ);
247 NET_EPOCH_EXIT(et);
248 CURVNET_RESTORE();
249 return (ifp != NULL ? 0 : EINVAL);
250 }
251
252 unsigned short
linux_ifflags(struct ifnet * ifp)253 linux_ifflags(struct ifnet *ifp)
254 {
255 unsigned short flags;
256
257 NET_EPOCH_ASSERT();
258
259 flags = if_getflags(ifp) | if_getdrvflags(ifp);
260 return (bsd_to_linux_ifflags(flags));
261 }
262
263 unsigned short
bsd_to_linux_ifflags(int fl)264 bsd_to_linux_ifflags(int fl)
265 {
266 unsigned short flags = 0;
267
268 if (fl & IFF_UP)
269 flags |= LINUX_IFF_UP;
270 if (fl & IFF_BROADCAST)
271 flags |= LINUX_IFF_BROADCAST;
272 if (fl & IFF_DEBUG)
273 flags |= LINUX_IFF_DEBUG;
274 if (fl & IFF_LOOPBACK)
275 flags |= LINUX_IFF_LOOPBACK;
276 if (fl & IFF_POINTOPOINT)
277 flags |= LINUX_IFF_POINTOPOINT;
278 if (fl & IFF_DRV_RUNNING)
279 flags |= LINUX_IFF_RUNNING;
280 if (fl & IFF_NOARP)
281 flags |= LINUX_IFF_NOARP;
282 if (fl & IFF_PROMISC)
283 flags |= LINUX_IFF_PROMISC;
284 if (fl & IFF_ALLMULTI)
285 flags |= LINUX_IFF_ALLMULTI;
286 if (fl & IFF_MULTICAST)
287 flags |= LINUX_IFF_MULTICAST;
288 return (flags);
289 }
290
291 static u_int
linux_ifhwaddr_cb(void * arg,struct ifaddr * ifa,u_int count)292 linux_ifhwaddr_cb(void *arg, struct ifaddr *ifa, u_int count)
293 {
294 struct sockaddr_dl *sdl = (struct sockaddr_dl *)ifa->ifa_addr;
295 struct l_sockaddr *lsa = arg;
296
297 if (count > 0)
298 return (0);
299 if (sdl->sdl_type != IFT_ETHER)
300 return (0);
301 bzero(lsa, sizeof(*lsa));
302 lsa->sa_family = LINUX_ARPHRD_ETHER;
303 bcopy(LLADDR(sdl), lsa->sa_data, LINUX_IFHWADDRLEN);
304 return (1);
305 }
306
307 int
linux_ifhwaddr(struct ifnet * ifp,struct l_sockaddr * lsa)308 linux_ifhwaddr(struct ifnet *ifp, struct l_sockaddr *lsa)
309 {
310
311 NET_EPOCH_ASSERT();
312
313 if (ifp->if_type == IFT_LOOP) {
314 bzero(lsa, sizeof(*lsa));
315 lsa->sa_family = LINUX_ARPHRD_LOOPBACK;
316 return (0);
317 }
318 if (ifp->if_type != IFT_ETHER)
319 return (ENOENT);
320 if (if_foreach_addr_type(ifp, AF_LINK, linux_ifhwaddr_cb, lsa) > 0)
321 return (0);
322 return (ENOENT);
323 }
324