xref: /freebsd/sys/compat/linux/linux.c (revision daceb336172a6b0572de864b97e70b28451ca636)
1 /*-
2  * Copyright (c) 2015 Dmitry Chagin
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/ctype.h>
33 #include <sys/jail.h>
34 #include <sys/lock.h>
35 #include <sys/signalvar.h>
36 #include <sys/socket.h>
37 
38 #include <net/if.h>
39 #include <net/if_var.h>
40 #include <net/if_dl.h>
41 #include <net/if_types.h>
42 
43 #include <compat/linux/linux.h>
44 #include <compat/linux/linux_common.h>
45 
46 CTASSERT(LINUX_IFNAMSIZ == IFNAMSIZ);
47 
48 static int bsd_to_linux_sigtbl[LINUX_SIGTBLSZ] = {
49 	LINUX_SIGHUP,	/* SIGHUP */
50 	LINUX_SIGINT,	/* SIGINT */
51 	LINUX_SIGQUIT,	/* SIGQUIT */
52 	LINUX_SIGILL,	/* SIGILL */
53 	LINUX_SIGTRAP,	/* SIGTRAP */
54 	LINUX_SIGABRT,	/* SIGABRT */
55 	0,		/* SIGEMT */
56 	LINUX_SIGFPE,	/* SIGFPE */
57 	LINUX_SIGKILL,	/* SIGKILL */
58 	LINUX_SIGBUS,	/* SIGBUS */
59 	LINUX_SIGSEGV,	/* SIGSEGV */
60 	LINUX_SIGSYS,	/* SIGSYS */
61 	LINUX_SIGPIPE,	/* SIGPIPE */
62 	LINUX_SIGALRM,	/* SIGALRM */
63 	LINUX_SIGTERM,	/* SIGTERM */
64 	LINUX_SIGURG,	/* SIGURG */
65 	LINUX_SIGSTOP,	/* SIGSTOP */
66 	LINUX_SIGTSTP,	/* SIGTSTP */
67 	LINUX_SIGCONT,	/* SIGCONT */
68 	LINUX_SIGCHLD,	/* SIGCHLD */
69 	LINUX_SIGTTIN,	/* SIGTTIN */
70 	LINUX_SIGTTOU,	/* SIGTTOU */
71 	LINUX_SIGIO,	/* SIGIO */
72 	LINUX_SIGXCPU,	/* SIGXCPU */
73 	LINUX_SIGXFSZ,	/* SIGXFSZ */
74 	LINUX_SIGVTALRM,/* SIGVTALRM */
75 	LINUX_SIGPROF,	/* SIGPROF */
76 	LINUX_SIGWINCH,	/* SIGWINCH */
77 	0,		/* SIGINFO */
78 	LINUX_SIGUSR1,	/* SIGUSR1 */
79 	LINUX_SIGUSR2	/* SIGUSR2 */
80 };
81 
82 static int linux_to_bsd_sigtbl[LINUX_SIGTBLSZ] = {
83 	SIGHUP,		/* LINUX_SIGHUP */
84 	SIGINT,		/* LINUX_SIGINT */
85 	SIGQUIT,	/* LINUX_SIGQUIT */
86 	SIGILL,		/* LINUX_SIGILL */
87 	SIGTRAP,	/* LINUX_SIGTRAP */
88 	SIGABRT,	/* LINUX_SIGABRT */
89 	SIGBUS,		/* LINUX_SIGBUS */
90 	SIGFPE,		/* LINUX_SIGFPE */
91 	SIGKILL,	/* LINUX_SIGKILL */
92 	SIGUSR1,	/* LINUX_SIGUSR1 */
93 	SIGSEGV,	/* LINUX_SIGSEGV */
94 	SIGUSR2,	/* LINUX_SIGUSR2 */
95 	SIGPIPE,	/* LINUX_SIGPIPE */
96 	SIGALRM,	/* LINUX_SIGALRM */
97 	SIGTERM,	/* LINUX_SIGTERM */
98 	SIGBUS,		/* LINUX_SIGSTKFLT */
99 	SIGCHLD,	/* LINUX_SIGCHLD */
100 	SIGCONT,	/* LINUX_SIGCONT */
101 	SIGSTOP,	/* LINUX_SIGSTOP */
102 	SIGTSTP,	/* LINUX_SIGTSTP */
103 	SIGTTIN,	/* LINUX_SIGTTIN */
104 	SIGTTOU,	/* LINUX_SIGTTOU */
105 	SIGURG,		/* LINUX_SIGURG */
106 	SIGXCPU,	/* LINUX_SIGXCPU */
107 	SIGXFSZ,	/* LINUX_SIGXFSZ */
108 	SIGVTALRM,	/* LINUX_SIGVTALARM */
109 	SIGPROF,	/* LINUX_SIGPROF */
110 	SIGWINCH,	/* LINUX_SIGWINCH */
111 	SIGIO,		/* LINUX_SIGIO */
112 	/*
113 	 * FreeBSD does not have SIGPWR signal, map Linux SIGPWR signal
114 	 * to the first unused FreeBSD signal number. Since Linux supports
115 	 * signals from 1 to 64 we are ok here as our SIGRTMIN = 65.
116 	 */
117 	SIGRTMIN,	/* LINUX_SIGPWR */
118 	SIGSYS		/* LINUX_SIGSYS */
119 };
120 
121 /*
122  * Map Linux RT signals to the FreeBSD RT signals.
123  */
124 static inline int
125 linux_to_bsd_rt_signal(int sig)
126 {
127 
128 	return (SIGRTMIN + 1 + sig - LINUX_SIGRTMIN);
129 }
130 
131 static inline int
132 bsd_to_linux_rt_signal(int sig)
133 {
134 
135 	return (sig - SIGRTMIN - 1 + LINUX_SIGRTMIN);
136 }
137 
138 int
139 linux_to_bsd_signal(int sig)
140 {
141 
142 	KASSERT(sig > 0 && sig <= LINUX_SIGRTMAX, ("invalid Linux signal %d\n", sig));
143 
144 	if (sig < LINUX_SIGRTMIN)
145 		return (linux_to_bsd_sigtbl[_SIG_IDX(sig)]);
146 
147 	return (linux_to_bsd_rt_signal(sig));
148 }
149 
150 int
151 bsd_to_linux_signal(int sig)
152 {
153 
154 	if (sig <= LINUX_SIGTBLSZ)
155 		return (bsd_to_linux_sigtbl[_SIG_IDX(sig)]);
156 	if (sig == SIGRTMIN)
157 		return (LINUX_SIGPWR);
158 
159 	return (bsd_to_linux_rt_signal(sig));
160 }
161 
162 int
163 linux_to_bsd_sigaltstack(int lsa)
164 {
165 	int bsa = 0;
166 
167 	if (lsa & LINUX_SS_DISABLE)
168 		bsa |= SS_DISABLE;
169 	/*
170 	 * Linux ignores SS_ONSTACK flag for ss
171 	 * parameter while FreeBSD prohibits it.
172 	 */
173 	return (bsa);
174 }
175 
176 int
177 bsd_to_linux_sigaltstack(int bsa)
178 {
179 	int lsa = 0;
180 
181 	if (bsa & SS_DISABLE)
182 		lsa |= LINUX_SS_DISABLE;
183 	if (bsa & SS_ONSTACK)
184 		lsa |= LINUX_SS_ONSTACK;
185 	return (lsa);
186 }
187 
188 void
189 linux_to_bsd_sigset(l_sigset_t *lss, sigset_t *bss)
190 {
191 	int b, l;
192 
193 	SIGEMPTYSET(*bss);
194 	for (l = 1; l <= LINUX_SIGRTMAX; l++) {
195 		if (LINUX_SIGISMEMBER(*lss, l)) {
196 			b = linux_to_bsd_signal(l);
197 			if (b)
198 				SIGADDSET(*bss, b);
199 		}
200 	}
201 }
202 
203 void
204 bsd_to_linux_sigset(sigset_t *bss, l_sigset_t *lss)
205 {
206 	int b, l;
207 
208 	LINUX_SIGEMPTYSET(*lss);
209 	for (b = 1; b <= SIGRTMAX; b++) {
210 		if (SIGISMEMBER(*bss, b)) {
211 			l = bsd_to_linux_signal(b);
212 			if (l)
213 				LINUX_SIGADDSET(*lss, l);
214 		}
215 	}
216 }
217 
218 /*
219  * Translate a Linux interface name to a FreeBSD interface name,
220  * and return the associated ifnet structure
221  * bsdname and lxname need to be least IFNAMSIZ bytes long, but
222  * can point to the same buffer.
223  */
224 struct ifnet *
225 ifname_linux_to_bsd(struct thread *td, const char *lxname, char *bsdname)
226 {
227 	struct ifnet *ifp;
228 	int len, unit;
229 	char *ep;
230 	int index;
231 	bool is_eth, is_lo;
232 
233 	for (len = 0; len < LINUX_IFNAMSIZ; ++len)
234 		if (!isalpha(lxname[len]) || lxname[len] == '\0')
235 			break;
236 	if (len == 0 || len == LINUX_IFNAMSIZ)
237 		return (NULL);
238 	/* Linux loopback interface name is lo (not lo0) */
239 	is_lo = (len == 2 && strncmp(lxname, "lo", len) == 0);
240 	unit = (int)strtoul(lxname + len, &ep, 10);
241 	if ((ep == NULL || ep == lxname + len || ep >= lxname + LINUX_IFNAMSIZ) &&
242 	    is_lo == 0)
243 		return (NULL);
244 	index = 0;
245 	is_eth = (len == 3 && strncmp(lxname, "eth", len) == 0);
246 
247 	CURVNET_SET(TD_TO_VNET(td));
248 	IFNET_RLOCK();
249 	CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link) {
250 		/*
251 		 * Allow Linux programs to use FreeBSD names. Don't presume
252 		 * we never have an interface named "eth", so don't make
253 		 * the test optional based on is_eth.
254 		 */
255 		if (strncmp(ifp->if_xname, lxname, LINUX_IFNAMSIZ) == 0)
256 			break;
257 		if (is_eth && IFP_IS_ETH(ifp) && unit == index++)
258 			break;
259 		if (is_lo && IFP_IS_LOOP(ifp))
260 			break;
261 	}
262 	IFNET_RUNLOCK();
263 	CURVNET_RESTORE();
264 	if (ifp != NULL && bsdname != NULL)
265 		strlcpy(bsdname, ifp->if_xname, IFNAMSIZ);
266 	return (ifp);
267 }
268 
269 void
270 linux_ifflags(struct ifnet *ifp, short *flags)
271 {
272 	unsigned short fl;
273 
274 	fl = (ifp->if_flags | ifp->if_drv_flags) & 0xffff;
275 	*flags = 0;
276 	if (fl & IFF_UP)
277 		*flags |= LINUX_IFF_UP;
278 	if (fl & IFF_BROADCAST)
279 		*flags |= LINUX_IFF_BROADCAST;
280 	if (fl & IFF_DEBUG)
281 		*flags |= LINUX_IFF_DEBUG;
282 	if (fl & IFF_LOOPBACK)
283 		*flags |= LINUX_IFF_LOOPBACK;
284 	if (fl & IFF_POINTOPOINT)
285 		*flags |= LINUX_IFF_POINTOPOINT;
286 	if (fl & IFF_DRV_RUNNING)
287 		*flags |= LINUX_IFF_RUNNING;
288 	if (fl & IFF_NOARP)
289 		*flags |= LINUX_IFF_NOARP;
290 	if (fl & IFF_PROMISC)
291 		*flags |= LINUX_IFF_PROMISC;
292 	if (fl & IFF_ALLMULTI)
293 		*flags |= LINUX_IFF_ALLMULTI;
294 	if (fl & IFF_MULTICAST)
295 		*flags |= LINUX_IFF_MULTICAST;
296 }
297 
298 int
299 linux_ifhwaddr(struct ifnet *ifp, struct l_sockaddr *lsa)
300 {
301 	struct ifaddr *ifa;
302 	struct sockaddr_dl *sdl;
303 
304 	if (IFP_IS_LOOP(ifp)) {
305 		bzero(lsa, sizeof(*lsa));
306 		lsa->sa_family = LINUX_ARPHRD_LOOPBACK;
307 		return (0);
308 	}
309 
310 	if (!IFP_IS_ETH(ifp))
311 		return (ENOENT);
312 
313 	CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
314 		sdl = (struct sockaddr_dl*)ifa->ifa_addr;
315 		if (sdl != NULL && (sdl->sdl_family == AF_LINK) &&
316 		    (sdl->sdl_type == IFT_ETHER)) {
317 			bzero(lsa, sizeof(*lsa));
318 			lsa->sa_family = LINUX_ARPHRD_ETHER;
319 			bcopy(LLADDR(sdl), lsa->sa_data, LINUX_IFHWADDRLEN);
320 			return (0);
321 		}
322 	}
323 
324 	return (ENOENT);
325 }
326