1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1994 Christos Zoulas
5 * Copyright (c) 1995 Frank van der Linden
6 * Copyright (c) 1995 Scott Bartram
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. The name of the author may not be used to endorse or promote products
18 * derived from this software without specific prior written permission
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
21 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
24 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 *
31 * from: svr4_util.c,v 1.5 1995/01/22 23:44:50 christos Exp
32 */
33
34 #include <sys/param.h>
35 #include <sys/bus.h>
36 #include <sys/conf.h>
37 #include <sys/fcntl.h>
38 #include <sys/jail.h>
39 #include <sys/malloc.h>
40 #include <sys/namei.h>
41 #include <sys/proc.h>
42 #include <sys/stat.h>
43 #include <sys/stdarg.h>
44 #include <sys/syscallsubr.h>
45 #include <sys/vnode.h>
46
47 #include <compat/linux/linux_dtrace.h>
48 #include <compat/linux/linux_mib.h>
49 #include <compat/linux/linux_util.h>
50
51 MALLOC_DEFINE(M_LINUX, "linux", "Linux mode structures");
52 MALLOC_DEFINE(M_EPOLL, "lepoll", "Linux events structures");
53
54 FEATURE(linuxulator_v4l, "V4L ioctl wrapper support in the linuxulator");
55 FEATURE(linuxulator_v4l2, "V4L2 ioctl wrapper support in the linuxulator");
56
57 /**
58 * Special DTrace provider for the linuxulator.
59 *
60 * In this file we define the provider for the entire linuxulator. All
61 * modules (= files of the linuxulator) use it.
62 *
63 * We define a different name depending on the emulated bitsize, see
64 * ../../<ARCH>/linux{,32}/linux.h, e.g.:
65 * native bitsize = linuxulator
66 * amd64, 32bit emulation = linuxulator32
67 */
68 LIN_SDT_PROVIDER_DEFINE(linuxulator);
69 LIN_SDT_PROVIDER_DEFINE(linuxulator32);
70
71 char linux_emul_path[MAXPATHLEN] = "/compat/linux";
72
73 SYSCTL_STRING(_compat_linux, OID_AUTO, emul_path, CTLFLAG_RWTUN,
74 linux_emul_path, sizeof(linux_emul_path),
75 "Linux runtime environment path");
76
77 int
linux_pwd_onexec(struct thread * td)78 linux_pwd_onexec(struct thread *td)
79 {
80 struct nameidata nd;
81 int error;
82
83 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, linux_emul_path);
84 error = namei(&nd);
85 if (error != 0) {
86 /* Do not prevent execution if altroot is non-existent. */
87 pwd_altroot(td, NULL);
88 return (0);
89 }
90 NDFREE_PNBUF(&nd);
91 pwd_altroot(td, nd.ni_vp);
92 vrele(nd.ni_vp);
93 return (0);
94 }
95
96 void
linux_pwd_onexec_native(struct thread * td)97 linux_pwd_onexec_native(struct thread *td)
98 {
99
100 pwd_altroot(td, NULL);
101 }
102
103 void
linux_msg(const struct thread * td,const char * fmt,...)104 linux_msg(const struct thread *td, const char *fmt, ...)
105 {
106 va_list ap;
107 struct proc *p;
108
109 if (linux_debug == 0)
110 return;
111
112 p = td->td_proc;
113 printf("linux: jid %d pid %d (%s): ", p->p_ucred->cr_prison->pr_id,
114 (int)p->p_pid, p->p_comm);
115 va_start(ap, fmt);
116 vprintf(fmt, ap);
117 va_end(ap);
118 printf("\n");
119 }
120
121 struct device_element
122 {
123 TAILQ_ENTRY(device_element) list;
124 struct linux_device_handler entry;
125 };
126
127 static TAILQ_HEAD(, device_element) devices =
128 TAILQ_HEAD_INITIALIZER(devices);
129
130 static struct linux_device_handler null_handler =
131 { "mem", "mem", "null", "null", 1, 3, 1};
132
133 DATA_SET(linux_device_handler_set, null_handler);
134
135 char *
linux_driver_get_name_dev(device_t dev)136 linux_driver_get_name_dev(device_t dev)
137 {
138 struct device_element *de;
139 const char *device_name = device_get_name(dev);
140
141 if (device_name == NULL)
142 return (NULL);
143 TAILQ_FOREACH(de, &devices, list) {
144 if (strcmp(device_name, de->entry.bsd_driver_name) == 0)
145 return (de->entry.linux_driver_name);
146 }
147
148 return (NULL);
149 }
150
151 int
linux_driver_get_major_minor(const char * node,int * major,int * minor)152 linux_driver_get_major_minor(const char *node, int *major, int *minor)
153 {
154 struct device_element *de;
155 unsigned long devno;
156 size_t sz;
157
158 if (node == NULL || major == NULL || minor == NULL)
159 return (1);
160
161 sz = sizeof("pts/") - 1;
162 if (strncmp(node, "pts/", sz) == 0 && node[sz] != '\0') {
163 /*
164 * Linux checks major and minors of the slave device
165 * to make sure it's a pty device, so let's make him
166 * believe it is.
167 */
168 devno = strtoul(node + sz, NULL, 10);
169 *major = 136 + (devno / 256);
170 *minor = devno % 256;
171 return (0);
172 }
173
174 sz = sizeof("dri/card") - 1;
175 if (strncmp(node, "dri/card", sz) == 0 && node[sz] != '\0') {
176 devno = strtoul(node + sz, NULL, 10);
177 *major = 226 + (devno / 256);
178 *minor = devno % 256;
179 return (0);
180 }
181 sz = sizeof("dri/controlD") - 1;
182 if (strncmp(node, "dri/controlD", sz) == 0 && node[sz] != '\0') {
183 devno = strtoul(node + sz, NULL, 10);
184 *major = 226 + (devno / 256);
185 *minor = devno % 256;
186 return (0);
187 }
188 sz = sizeof("dri/renderD") - 1;
189 if (strncmp(node, "dri/renderD", sz) == 0 && node[sz] != '\0') {
190 devno = strtoul(node + sz, NULL, 10);
191 *major = 226 + (devno / 256);
192 *minor = devno % 256;
193 return (0);
194 }
195 sz = sizeof("drm/") - 1;
196 if (strncmp(node, "drm/", sz) == 0 && node[sz] != '\0') {
197 devno = strtoul(node + sz, NULL, 10);
198 *major = 226 + (devno / 256);
199 *minor = devno % 256;
200 return (0);
201 }
202
203 TAILQ_FOREACH(de, &devices, list) {
204 if (strcmp(node, de->entry.bsd_device_name) == 0) {
205 *major = de->entry.linux_major;
206 *minor = de->entry.linux_minor;
207 return (0);
208 }
209 }
210
211 return (1);
212 }
213
214 int
linux_vn_get_major_minor(const struct vnode * vp,int * major,int * minor)215 linux_vn_get_major_minor(const struct vnode *vp, int *major, int *minor)
216 {
217 int error;
218
219 if (vp->v_type != VCHR)
220 return (ENOTBLK);
221 dev_lock();
222 if (vp->v_rdev == NULL) {
223 dev_unlock();
224 return (ENXIO);
225 }
226 error = linux_driver_get_major_minor(devtoname(vp->v_rdev),
227 major, minor);
228 dev_unlock();
229 return (error);
230 }
231
232 void
translate_vnhook_major_minor(struct vnode * vp,struct stat * sb)233 translate_vnhook_major_minor(struct vnode *vp, struct stat *sb)
234 {
235 int major, minor;
236
237 if (vn_isdisk(vp)) {
238 sb->st_mode &= ~S_IFMT;
239 sb->st_mode |= S_IFBLK;
240 }
241
242 /*
243 * Return the same st_dev for every devfs instance. The reason
244 * for this is to work around an idiosyncrasy of glibc getttynam()
245 * implementation: it checks whether st_dev returned for fd 0
246 * is the same as st_dev returned for the target of /proc/self/fd/0
247 * symlink, and with linux chroots having their own devfs instance,
248 * the check will fail if you chroot into it.
249 */
250 if (rootdevmp != NULL && vp->v_mount->mnt_vfc == rootdevmp->mnt_vfc)
251 sb->st_dev = rootdevmp->mnt_stat.f_fsid.val[0];
252
253 if (linux_vn_get_major_minor(vp, &major, &minor) == 0)
254 sb->st_rdev = makedev(major, minor);
255 }
256
257 char *
linux_get_char_devices(void)258 linux_get_char_devices(void)
259 {
260 struct device_element *de;
261 char *temp, *string, *last;
262 char formated[256];
263 int current_size = 0, string_size = 1024;
264
265 string = malloc(string_size, M_LINUX, M_WAITOK);
266 string[0] = '\000';
267 last = "";
268 TAILQ_FOREACH(de, &devices, list) {
269 if (!de->entry.linux_char_device)
270 continue;
271 temp = string;
272 if (strcmp(last, de->entry.bsd_driver_name) != 0) {
273 last = de->entry.bsd_driver_name;
274
275 snprintf(formated, sizeof(formated), "%3d %s\n",
276 de->entry.linux_major,
277 de->entry.linux_device_name);
278 if (strlen(formated) + current_size
279 >= string_size) {
280 string_size *= 2;
281 string = malloc(string_size,
282 M_LINUX, M_WAITOK);
283 bcopy(temp, string, current_size);
284 free(temp, M_LINUX);
285 }
286 strcat(string, formated);
287 current_size = strlen(string);
288 }
289 }
290
291 return (string);
292 }
293
294 void
linux_free_get_char_devices(char * string)295 linux_free_get_char_devices(char *string)
296 {
297
298 free(string, M_LINUX);
299 }
300
301 static int linux_major_starting = 200;
302
303 int
linux_device_register_handler(struct linux_device_handler * d)304 linux_device_register_handler(struct linux_device_handler *d)
305 {
306 struct device_element *de;
307
308 if (d == NULL)
309 return (EINVAL);
310
311 de = malloc(sizeof(*de), M_LINUX, M_WAITOK);
312 if (d->linux_major < 0) {
313 d->linux_major = linux_major_starting++;
314 }
315 bcopy(d, &de->entry, sizeof(*d));
316
317 /* Add the element to the list, sorted on span. */
318 TAILQ_INSERT_TAIL(&devices, de, list);
319
320 return (0);
321 }
322
323 int
linux_device_unregister_handler(struct linux_device_handler * d)324 linux_device_unregister_handler(struct linux_device_handler *d)
325 {
326 struct device_element *de;
327
328 if (d == NULL)
329 return (EINVAL);
330
331 TAILQ_FOREACH(de, &devices, list) {
332 if (bcmp(d, &de->entry, sizeof(*d)) == 0) {
333 TAILQ_REMOVE(&devices, de, list);
334 free(de, M_LINUX);
335
336 return (0);
337 }
338 }
339
340 return (EINVAL);
341 }
342