1 /**
2  * sload.c
3  *
4  * Copyright (C) 2015 Huawei Ltd.
5  * Witten by:
6  *   Hou Pengyang <houpengyang@huawei.com>
7  *   Liu Shuoran <liushuoran@huawei.com>
8  *   Jaegeuk Kim <jaegeuk@kernel.org>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  */
14 #define _GNU_SOURCE
15 #include "fsck.h"
16 #include <libgen.h>
17 #include <dirent.h>
18 #ifdef HAVE_MNTENT_H
19 #include <mntent.h>
20 #endif
21 
22 #ifdef HAVE_LIBSELINUX
23 static struct selabel_handle *sehnd = NULL;
24 #endif
25 
26 typedef void (*fs_config_f)(const char *path, int dir,
27 			    const char *target_out_path,
28 			    unsigned *uid, unsigned *gid,
29 			    unsigned *mode, uint64_t *capabilities);
30 
31 static fs_config_f fs_config_func = NULL;
32 
33 #ifdef WITH_ANDROID
34 #include <selinux/android.h>
35 #include <private/android_filesystem_config.h>
36 #include <private/canned_fs_config.h>
37 #include <private/fs_config.h>
38 #endif
39 
filter_dot(const struct dirent * d)40 static int filter_dot(const struct dirent *d)
41 {
42 	return (strcmp(d->d_name, "..") && strcmp(d->d_name, "."));
43 }
44 
f2fs_make_directory(struct f2fs_sb_info * sbi,int entries,struct dentry * de)45 static int f2fs_make_directory(struct f2fs_sb_info *sbi,
46 				int entries, struct dentry *de)
47 {
48 	int ret = 0;
49 	int i = 0;
50 
51 	for (i = 0; i < entries; i++) {
52 		if (de[i].file_type == F2FS_FT_DIR)
53 			ret = f2fs_mkdir(sbi, de + i);
54 		else if (de[i].file_type == F2FS_FT_REG_FILE)
55 			ret = f2fs_create(sbi, de + i);
56 		else if (de[i].file_type == F2FS_FT_SYMLINK)
57 			ret = f2fs_symlink(sbi, de + i);
58 
59 		if (ret)
60 			break;
61 	}
62 
63 	return ret;
64 }
65 
66 #ifdef HAVE_LIBSELINUX
set_selinux_xattr(struct f2fs_sb_info * sbi,const char * path,nid_t ino,int mode)67 static int set_selinux_xattr(struct f2fs_sb_info *sbi, const char *path,
68 							nid_t ino, int mode)
69 {
70 	char *secontext = NULL;
71 	char *mnt_path = NULL;
72 
73 	if (!sehnd)
74 		return 0;
75 
76 	if (asprintf(&mnt_path, "%s%s", c.mount_point, path) <= 0) {
77 		ERR_MSG("cannot allocate security path for %s%s\n",
78 						c.mount_point, path);
79 		return -ENOMEM;
80 	}
81 
82 	/* set root inode selinux context */
83 	if (selabel_lookup(sehnd, &secontext, mnt_path, mode) < 0) {
84 		ERR_MSG("cannot lookup security context for %s\n", mnt_path);
85 		free(mnt_path);
86 		return -EINVAL;
87 	}
88 
89 	if (secontext) {
90 		MSG(2, "%s (%d) -> SELinux context = %s\n",
91 						mnt_path, ino, secontext);
92 		inode_set_selinux(sbi, ino, secontext);
93 	}
94 	freecon(secontext);
95 	free(mnt_path);
96 	return 0;
97 }
98 #else
99 #define set_selinux_xattr(...)	0
100 #endif
101 
set_perms_and_caps(struct dentry * de)102 static int set_perms_and_caps(struct dentry *de)
103 {
104 	uint64_t capabilities = 0;
105 	unsigned int uid = 0, gid = 0, imode = 0;
106 	char *mnt_path = NULL;
107 	char *mount_path = c.mount_point;
108 
109 	/*
110 	 * de->path already has "/" in the beginning of it.
111 	 * Need to remove "/" when c.mount_point is "/", not to add it twice.
112 	 */
113 	if (strlen(c.mount_point) == 1 && c.mount_point[0] == '/')
114 		mount_path = "";
115 
116 	if (asprintf(&mnt_path, "%s%s", mount_path, de->path) <= 0) {
117 		ERR_MSG("cannot allocate mount path for %s%s\n",
118 				mount_path, de->path);
119 		return -ENOMEM;
120 	}
121 
122 	/* Permissions */
123 	if (fs_config_func != NULL) {
124 		fs_config_func(mnt_path, de->file_type == F2FS_FT_DIR,
125 				c.target_out_dir, &uid, &gid, &imode,
126 				&capabilities);
127 		de->uid = uid & 0xffff;
128 		de->gid = gid & 0xffff;
129 		de->mode = (de->mode & S_IFMT) | (imode & 0xffff);
130 		de->capabilities = capabilities;
131 	}
132 	MSG(2, "%s -> mode = 0x%x, uid = 0x%x, gid = 0x%x, "
133 			"capabilities = 0x%"PRIx64"\n",
134 		mnt_path, de->mode, de->uid, de->gid, de->capabilities);
135 	free(mnt_path);
136 	return 0;
137 }
138 
set_inode_metadata(struct dentry * de)139 static void set_inode_metadata(struct dentry *de)
140 {
141 	struct stat stat;
142 	int ret;
143 
144 	ret = lstat(de->full_path, &stat);
145 	if (ret < 0) {
146 		ERR_MSG("lstat failure\n");
147 		ASSERT(0);
148 	}
149 
150 	if (S_ISREG(stat.st_mode)) {
151 		if (stat.st_nlink > 1) {
152 			/*
153 			 * This file might have multiple links to it, so remember
154 			 * device and inode.
155 			 */
156 			de->from_devino = stat.st_dev;
157 			de->from_devino <<= 32;
158 			de->from_devino |= stat.st_ino;
159 		}
160 		de->file_type = F2FS_FT_REG_FILE;
161 	} else if (S_ISDIR(stat.st_mode)) {
162 		de->file_type = F2FS_FT_DIR;
163 	} else if (S_ISCHR(stat.st_mode)) {
164 		de->file_type = F2FS_FT_CHRDEV;
165 	} else if (S_ISBLK(stat.st_mode)) {
166 		de->file_type = F2FS_FT_BLKDEV;
167 	} else if (S_ISFIFO(stat.st_mode)) {
168 		de->file_type = F2FS_FT_FIFO;
169 	} else if (S_ISSOCK(stat.st_mode)) {
170 		de->file_type = F2FS_FT_SOCK;
171 	} else if (S_ISLNK(stat.st_mode)) {
172 		de->file_type = F2FS_FT_SYMLINK;
173 		de->link = calloc(F2FS_BLKSIZE, 1);
174 		ASSERT(de->link);
175 		ret = readlink(de->full_path, de->link, F2FS_BLKSIZE - 1);
176 		ASSERT(ret >= 0);
177 	} else {
178 		ERR_MSG("unknown file type on %s", de->path);
179 		ASSERT(0);
180 	}
181 
182 	de->size = stat.st_size;
183 	de->mode = stat.st_mode &
184 			(S_IFMT|S_ISUID|S_ISGID|S_ISVTX|S_IRWXU|S_IRWXG|S_IRWXO);
185 	if (c.fixed_time == -1 && c.from_dir)
186 		de->mtime = stat.st_mtime;
187 	else
188 		de->mtime = c.fixed_time;
189 
190 	if (c.preserve_perms) {
191 		de->uid = stat.st_uid;
192 		de->gid = stat.st_gid;
193 	}
194 
195 	set_perms_and_caps(de);
196 }
197 
build_directory(struct f2fs_sb_info * sbi,const char * full_path,const char * dir_path,const char * target_out_dir,nid_t dir_ino)198 static int build_directory(struct f2fs_sb_info *sbi, const char *full_path,
199 			const char *dir_path, const char *target_out_dir,
200 			nid_t dir_ino)
201 {
202 	int entries = 0;
203 	struct dentry *dentries;
204 	struct dirent **namelist = NULL;
205 	int i = 0, ret = 0;
206 
207 	entries = scandir(full_path, &namelist, filter_dot, (void *)alphasort);
208 	if (entries < 0) {
209 		ERR_MSG("No entries in %s\n", full_path);
210 		return -ENOENT;
211 	}
212 
213 	dentries = calloc(entries, sizeof(struct dentry));
214 	ASSERT(dentries);
215 
216 	for (i = 0; i < entries; i++) {
217 		dentries[i].name = (unsigned char *)strdup(namelist[i]->d_name);
218 		if (dentries[i].name == NULL) {
219 			ERR_MSG("Skip: ENOMEM\n");
220 			continue;
221 		}
222 		dentries[i].len = strlen((char *)dentries[i].name);
223 
224 		ret = asprintf(&dentries[i].path, "%s%s",
225 					dir_path, namelist[i]->d_name);
226 		ASSERT(ret > 0);
227 		ret = asprintf(&dentries[i].full_path, "%s/%s",
228 					full_path, namelist[i]->d_name);
229 		ASSERT(ret > 0);
230 		free(namelist[i]);
231 
232 		set_inode_metadata(dentries + i);
233 
234 		dentries[i].pino = dir_ino;
235 	}
236 
237 	free(namelist);
238 
239 	ret = f2fs_make_directory(sbi, entries, dentries);
240 	if (ret)
241 		goto out_free;
242 
243 	for (i = 0; i < entries; i++) {
244 		if (dentries[i].file_type == F2FS_FT_REG_FILE) {
245 			f2fs_build_file(sbi, dentries + i);
246 		} else if (dentries[i].file_type == F2FS_FT_DIR) {
247 			char *subdir_full_path = NULL;
248 			char *subdir_dir_path = NULL;
249 
250 			ret = asprintf(&subdir_full_path, "%s",
251 							dentries[i].full_path);
252 			ASSERT(ret > 0);
253 			ret = asprintf(&subdir_dir_path, "%s/",
254 							dentries[i].path);
255 			ASSERT(ret > 0);
256 
257 			ret = build_directory(sbi, subdir_full_path,
258 						subdir_dir_path,
259 						target_out_dir,
260 						dentries[i].ino);
261 			free(subdir_full_path);
262 			free(subdir_dir_path);
263 
264 			if (ret)
265 				goto out_free;
266 		} else if (dentries[i].file_type == F2FS_FT_SYMLINK) {
267 			/*
268 			 * It is already done in f2fs_make_directory
269 			 * f2fs_make_symlink(sbi, dir_ino, &dentries[i]);
270 			 */
271 		} else {
272 			MSG(1, "Error unknown file type\n");
273 		}
274 
275 		ret = set_selinux_xattr(sbi, dentries[i].path,
276 					dentries[i].ino, dentries[i].mode);
277 		if (ret)
278 			goto out_free;
279 
280 		free(dentries[i].path);
281 		free(dentries[i].full_path);
282 		free((void *)dentries[i].name);
283 	}
284 out_free:
285 	for (; i < entries; i++) {
286 		free(dentries[i].path);
287 		free(dentries[i].full_path);
288 		free((void *)dentries[i].name);
289 	}
290 
291 	free(dentries);
292 	return 0;
293 }
294 
configure_files(void)295 static int configure_files(void)
296 {
297 #ifdef HAVE_LIBSELINUX
298 	if (!c.nr_opt)
299 		goto skip;
300 #if !defined(__ANDROID__)
301 	sehnd = selabel_open(SELABEL_CTX_FILE, c.seopt_file, c.nr_opt);
302 	if (!sehnd) {
303 		ERR_MSG("Failed to open file contexts \"%s\"",
304 					c.seopt_file[0].value);
305 			return -EINVAL;
306 	}
307 #else
308 	sehnd = selinux_android_file_context_handle();
309 	if (!sehnd) {
310 		ERR_MSG("Failed to get android file_contexts\n", c.mount_point);
311 		return -EINVAL;
312 	}
313 #endif
314 skip:
315 #endif
316 #ifdef WITH_ANDROID
317 	/* Load the FS config */
318 	if (c.fs_config_file) {
319 		int ret = load_canned_fs_config(c.fs_config_file);
320 
321 		if (ret < 0) {
322 			ERR_MSG("Failed to load fs_config \"%s\"",
323 						c.fs_config_file);
324 			return ret;
325 		}
326 		fs_config_func = canned_fs_config;
327 	} else {
328 		fs_config_func = fs_config;
329 	}
330 #endif
331 	return 0;
332 }
333 
f2fs_sload(struct f2fs_sb_info * sbi)334 int f2fs_sload(struct f2fs_sb_info *sbi)
335 {
336 	int ret = 0;
337 
338 	/* this requires for the below sanity checks */
339 	fsck_init(sbi);
340 
341 	ret = configure_files();
342 	if (ret) {
343 		ERR_MSG("Failed to configure files\n");
344 		return ret;
345 	}
346 
347 	/* flush NAT/SIT journal entries */
348 	flush_journal_entries(sbi);
349 
350 	/* initialize empty hardlink cache */
351 	sbi->hardlink_cache = 0;
352 
353 	ret = build_directory(sbi, c.from_dir, "/",
354 					c.target_out_dir, F2FS_ROOT_INO(sbi));
355 	if (ret) {
356 		ERR_MSG("Failed to build due to %d\n", ret);
357 		return ret;
358 	}
359 
360 	ret = set_selinux_xattr(sbi, c.mount_point,
361 					F2FS_ROOT_INO(sbi), S_IFDIR);
362 	if (ret) {
363 		ERR_MSG("Failed to set selinux for root: %d\n", ret);
364 		return ret;
365 	}
366 
367 	/* update curseg info; can update sit->types */
368 	move_curseg_info(sbi, SM_I(sbi)->main_blkaddr, 0);
369 	zero_journal_entries(sbi);
370 	write_curseg_info(sbi);
371 
372 	/* flush dirty sit entries */
373 	flush_sit_entries(sbi);
374 
375 	write_checkpoint(sbi);
376 	return 0;
377 }
378