xref: /freebsd-src/sys/contrib/openzfs/lib/libzfs/os/freebsd/libzfs_compat.c (revision e67e85659c0de33e617e5fbf1028c6e8b49eee53)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright (c) 2013 Martin Matuska <mm@FreeBSD.org>. All rights reserved.
24  */
25 #include "../../libzfs_impl.h"
26 #include <libzfs.h>
27 #include <libzutil.h>
28 #include <sys/sysctl.h>
29 #include <libintl.h>
30 #include <sys/linker.h>
31 #include <sys/module.h>
32 #include <sys/stat.h>
33 #include <sys/param.h>
34 
35 #ifdef IN_BASE
36 #define	ZFS_KMOD	"zfs"
37 #else
38 #define	ZFS_KMOD	"openzfs"
39 #endif
40 
41 
42 static int
43 execvPe(const char *name, const char *path, char * const *argv,
44     char * const *envp)
45 {
46 	const char **memp;
47 	size_t cnt, lp, ln;
48 	int eacces, save_errno;
49 	char buf[MAXPATHLEN];
50 	const char *bp, *np, *op, *p;
51 	struct stat sb;
52 
53 	eacces = 0;
54 
55 	/* If it's an absolute or relative path name, it's easy. */
56 	if (strchr(name, '/')) {
57 		bp = name;
58 		op = NULL;
59 		goto retry;
60 	}
61 	bp = buf;
62 
63 	/* If it's an empty path name, fail in the usual POSIX way. */
64 	if (*name == '\0') {
65 		errno = ENOENT;
66 		return (-1);
67 	}
68 
69 	op = path;
70 	ln = strlen(name);
71 	while (op != NULL) {
72 		np = strchrnul(op, ':');
73 
74 		/*
75 		 * It's a SHELL path -- double, leading and trailing colons
76 		 * mean the current directory.
77 		 */
78 		if (np == op) {
79 			/* Empty component. */
80 			p = ".";
81 			lp = 1;
82 		} else {
83 			/* Non-empty component. */
84 			p = op;
85 			lp = np - op;
86 		}
87 
88 		/* Advance to the next component or terminate after this. */
89 		if (*np == '\0')
90 			op = NULL;
91 		else
92 			op = np + 1;
93 
94 		/*
95 		 * If the path is too long complain.  This is a possible
96 		 * security issue; given a way to make the path too long
97 		 * the user may execute the wrong program.
98 		 */
99 		if (lp + ln + 2 > sizeof (buf)) {
100 			(void) write(STDERR_FILENO, "execvP: ", 8);
101 			(void) write(STDERR_FILENO, p, lp);
102 			(void) write(STDERR_FILENO, ": path too long\n",
103 			    16);
104 			continue;
105 		}
106 		memcpy(buf, p, lp);
107 		buf[lp] = '/';
108 		memcpy(buf + lp + 1, name, ln);
109 		buf[lp + ln + 1] = '\0';
110 
111 retry:		(void) execve(bp, argv, envp);
112 		switch (errno) {
113 		case E2BIG:
114 			goto done;
115 		case ELOOP:
116 		case ENAMETOOLONG:
117 		case ENOENT:
118 			break;
119 		case ENOEXEC:
120 			for (cnt = 0; argv[cnt]; ++cnt)
121 				;
122 
123 			/*
124 			 * cnt may be 0 above; always allocate at least
125 			 * 3 entries so that we can at least fit "sh", bp, and
126 			 * the NULL terminator.  We can rely on cnt to take into
127 			 * account the NULL terminator in all other scenarios,
128 			 * as we drop argv[0].
129 			 */
130 			memp = alloca(MAX(3, cnt + 2) * sizeof (char *));
131 			if (memp == NULL) {
132 				/* errno = ENOMEM; XXX override ENOEXEC? */
133 				goto done;
134 			}
135 			if (cnt > 0) {
136 				memp[0] = argv[0];
137 				memp[1] = bp;
138 				memcpy(memp + 2, argv + 1,
139 				    cnt * sizeof (char *));
140 			} else {
141 				memp[0] = "sh";
142 				memp[1] = bp;
143 				memp[2] = NULL;
144 			}
145 			(void) execve(_PATH_BSHELL,
146 			    __DECONST(char **, memp), envp);
147 			goto done;
148 		case ENOMEM:
149 			goto done;
150 		case ENOTDIR:
151 			break;
152 		case ETXTBSY:
153 			/*
154 			 * We used to retry here, but sh(1) doesn't.
155 			 */
156 			goto done;
157 		default:
158 			/*
159 			 * EACCES may be for an inaccessible directory or
160 			 * a non-executable file.  Call stat() to decide
161 			 * which.  This also handles ambiguities for EFAULT
162 			 * and EIO, and undocumented errors like ESTALE.
163 			 * We hope that the race for a stat() is unimportant.
164 			 */
165 			save_errno = errno;
166 			if (stat(bp, &sb) != 0)
167 				break;
168 			if (save_errno == EACCES) {
169 				eacces = 1;
170 				continue;
171 			}
172 			errno = save_errno;
173 			goto done;
174 		}
175 	}
176 	if (eacces)
177 		errno = EACCES;
178 	else
179 		errno = ENOENT;
180 done:
181 	return (-1);
182 }
183 
184 int
185 execvpe(const char *name, char * const argv[], char * const envp[])
186 {
187 	const char *path;
188 
189 	/* Get the path we're searching. */
190 	if ((path = getenv("PATH")) == NULL)
191 		path = _PATH_DEFPATH;
192 
193 	return (execvPe(name, path, argv, envp));
194 }
195 
196 static __thread char errbuf[ERRBUFLEN];
197 
198 const char *
199 libzfs_error_init(int error)
200 {
201 	char *msg = errbuf;
202 	size_t msglen = sizeof (errbuf);
203 
204 	if (modfind("zfs") < 0) {
205 		size_t len = snprintf(msg, msglen, dgettext(TEXT_DOMAIN,
206 		    "Failed to load %s module: "), ZFS_KMOD);
207 		msg += len;
208 		msglen -= len;
209 	}
210 
211 	(void) snprintf(msg, msglen, "%s", strerror(error));
212 
213 	return (errbuf);
214 }
215 
216 int
217 zfs_ioctl(libzfs_handle_t *hdl, int request, zfs_cmd_t *zc)
218 {
219 	return (lzc_ioctl_fd(hdl->libzfs_fd, request, zc));
220 }
221 
222 /*
223  * Verify the required ZFS_DEV device is available and optionally attempt
224  * to load the ZFS modules.  Under normal circumstances the modules
225  * should already have been loaded by some external mechanism.
226  */
227 int
228 libzfs_load_module(void)
229 {
230 	/*
231 	 * XXX: kldfind(ZFS_KMOD) would be nice here, but we retain
232 	 * modfind("zfs") so out-of-base openzfs userland works with the
233 	 * in-base module.
234 	 */
235 	if (modfind("zfs") < 0) {
236 		/* Not present in kernel, try loading it. */
237 		if (kldload(ZFS_KMOD) < 0 && errno != EEXIST) {
238 			return (errno);
239 		}
240 	}
241 	return (0);
242 }
243 
244 int
245 zpool_relabel_disk(libzfs_handle_t *hdl, const char *path, const char *msg)
246 {
247 	(void) hdl, (void) path, (void) msg;
248 	return (0);
249 }
250 
251 int
252 zpool_label_disk(libzfs_handle_t *hdl, zpool_handle_t *zhp, const char *name)
253 {
254 	(void) hdl, (void) zhp, (void) name;
255 	return (0);
256 }
257 
258 int
259 find_shares_object(differ_info_t *di)
260 {
261 	(void) di;
262 	return (0);
263 }
264 
265 int
266 zfs_destroy_snaps_nvl_os(libzfs_handle_t *hdl, nvlist_t *snaps)
267 {
268 	(void) hdl, (void) snaps;
269 	return (0);
270 }
271 
272 /*
273  * Attach/detach the given filesystem to/from the given jail.
274  */
275 int
276 zfs_jail(zfs_handle_t *zhp, int jailid, int attach)
277 {
278 	libzfs_handle_t *hdl = zhp->zfs_hdl;
279 	zfs_cmd_t zc = {"\0"};
280 	unsigned long cmd;
281 	int ret;
282 
283 	if (attach) {
284 		(void) snprintf(errbuf, sizeof (errbuf),
285 		    dgettext(TEXT_DOMAIN, "cannot jail '%s'"), zhp->zfs_name);
286 	} else {
287 		(void) snprintf(errbuf, sizeof (errbuf),
288 		    dgettext(TEXT_DOMAIN, "cannot unjail '%s'"), zhp->zfs_name);
289 	}
290 
291 	switch (zhp->zfs_type) {
292 	case ZFS_TYPE_VOLUME:
293 		zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
294 		    "volumes can not be jailed"));
295 		return (zfs_error(hdl, EZFS_BADTYPE, errbuf));
296 	case ZFS_TYPE_SNAPSHOT:
297 		zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
298 		    "snapshots can not be jailed"));
299 		return (zfs_error(hdl, EZFS_BADTYPE, errbuf));
300 	case ZFS_TYPE_BOOKMARK:
301 		zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
302 		    "bookmarks can not be jailed"));
303 		return (zfs_error(hdl, EZFS_BADTYPE, errbuf));
304 	case ZFS_TYPE_VDEV:
305 		zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
306 		    "vdevs can not be jailed"));
307 		return (zfs_error(hdl, EZFS_BADTYPE, errbuf));
308 	case ZFS_TYPE_INVALID:
309 		zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
310 		    "invalid zfs_type_t: ZFS_TYPE_INVALID"));
311 		return (zfs_error(hdl, EZFS_BADTYPE, errbuf));
312 	case ZFS_TYPE_POOL:
313 	case ZFS_TYPE_FILESYSTEM:
314 		/* OK */
315 		;
316 	}
317 	assert(zhp->zfs_type == ZFS_TYPE_FILESYSTEM);
318 
319 	(void) strlcpy(zc.zc_name, zhp->zfs_name, sizeof (zc.zc_name));
320 	zc.zc_objset_type = DMU_OST_ZFS;
321 	zc.zc_zoneid = jailid;
322 
323 	cmd = attach ? ZFS_IOC_JAIL : ZFS_IOC_UNJAIL;
324 	if ((ret = zfs_ioctl(hdl, cmd, &zc)) != 0)
325 		zfs_standard_error(hdl, errno, errbuf);
326 
327 	return (ret);
328 }
329 
330 /*
331  * Set loader options for next boot.
332  */
333 int
334 zpool_nextboot(libzfs_handle_t *hdl, uint64_t pool_guid, uint64_t dev_guid,
335     const char *command)
336 {
337 	zfs_cmd_t zc = {"\0"};
338 	nvlist_t *args;
339 
340 	args = fnvlist_alloc();
341 	fnvlist_add_uint64(args, ZPOOL_CONFIG_POOL_GUID, pool_guid);
342 	fnvlist_add_uint64(args, ZPOOL_CONFIG_GUID, dev_guid);
343 	fnvlist_add_string(args, "command", command);
344 	zcmd_write_src_nvlist(hdl, &zc, args);
345 	int error = zfs_ioctl(hdl, ZFS_IOC_NEXTBOOT, &zc);
346 	zcmd_free_nvlists(&zc);
347 	nvlist_free(args);
348 	return (error);
349 }
350 
351 /*
352  * Return allocated loaded module version, or NULL on error (with errno set)
353  */
354 char *
355 zfs_version_kernel(void)
356 {
357 	size_t l;
358 	if (sysctlbyname("vfs.zfs.version.module",
359 	    NULL, &l, NULL, 0) == -1)
360 		return (NULL);
361 	char *version = malloc(l);
362 	if (version == NULL)
363 		return (NULL);
364 	if (sysctlbyname("vfs.zfs.version.module",
365 	    version, &l, NULL, 0) == -1) {
366 		free(version);
367 		return (NULL);
368 	}
369 	return (version);
370 }
371