busybox/selinux/setfiles.c

/*
  setfiles: based on policycoreutils 2.0.19
  policycoreutils was released under GPL 2.
  Port to BusyBox (c) 2007 by Yuichi Nakamura <ynakam@hitachisoft.jp>
*/

#include "libbb.h"
#if ENABLE_FEATURE_SETFILES_CHECK_OPTION
#include <sepol/sepol.h>
#endif

#define MAX_EXCLUDES 50

struct edir {
	char *directory;
	size_t size;
};

struct globals {
	FILE *outfile;
	char *policyfile;
	char *rootpath;
	int rootpathlen;
	unsigned count;
	int excludeCtr;
	int errors;
	int verbose; /* getopt32 uses it, has to be int */
	smallint recurse; /* Recursive descent */
	smallint follow_mounts;
	/* Behavior flags determined based on setfiles vs. restorecon */
	smallint expand_realpath;  /* Expand paths via realpath */
	smallint abort_on_error; /* Abort the file tree walk upon an error */
	int add_assoc; /* Track inode associations for conflict detection */
	int matchpathcon_flags; /* Flags to matchpathcon */
	dev_t dev_id; /* Device id where target file exists */
	int nerr;
	struct edir excludeArray[MAX_EXCLUDES];
} FIX_ALIASING;
#define G (*(struct globals*)&bb_common_bufsiz1)
void BUG_setfiles_globals_too_big(void);
#define INIT_G() do { \
	if (sizeof(G) > COMMON_BUFSIZE) \
		BUG_setfiles_globals_too_big(); \
	/* memset(&G, 0, sizeof(G)); - already is */ \
} while (0)
#define outfile            (G.outfile           )
#define policyfile         (G.policyfile        )
#define rootpath           (G.rootpath          )
#define rootpathlen        (G.rootpathlen       )
#define count              (G.count             )
#define excludeCtr         (G.excludeCtr        )
#define errors             (G.errors            )
#define verbose            (G.verbose           )
#define recurse            (G.recurse           )
#define follow_mounts      (G.follow_mounts     )
#define expand_realpath    (G.expand_realpath   )
#define abort_on_error     (G.abort_on_error    )
#define add_assoc          (G.add_assoc         )
#define matchpathcon_flags (G.matchpathcon_flags)
#define dev_id             (G.dev_id            )
#define nerr               (G.nerr              )
#define excludeArray       (G.excludeArray      )

/* Must match getopt32 string! */
enum {
	OPT_d = (1 << 0),
	OPT_e = (1 << 1),
	OPT_f = (1 << 2),
	OPT_i = (1 << 3),
	OPT_l = (1 << 4),
	OPT_n = (1 << 5),
	OPT_p = (1 << 6),
	OPT_q = (1 << 7),
	OPT_r = (1 << 8),
	OPT_s = (1 << 9),
	OPT_v = (1 << 10),
	OPT_o = (1 << 11),
	OPT_F = (1 << 12),
	OPT_W = (1 << 13),
	OPT_c = (1 << 14), /* c only for setfiles */
	OPT_R = (1 << 14), /* R only for restorecon */
};
#define FLAG_d_debug         (option_mask32 & OPT_d)
#define FLAG_e               (option_mask32 & OPT_e)
#define FLAG_f               (option_mask32 & OPT_f)
#define FLAG_i_ignore_enoent (option_mask32 & OPT_i)
#define FLAG_l_take_log      (option_mask32 & OPT_l)
#define FLAG_n_dry_run       (option_mask32 & OPT_n)
#define FLAG_p_progress      (option_mask32 & OPT_p)
#define FLAG_q_quiet         (option_mask32 & OPT_q)
#define FLAG_r               (option_mask32 & OPT_r)
#define FLAG_s               (option_mask32 & OPT_s)
#define FLAG_v               (option_mask32 & OPT_v)
#define FLAG_o               (option_mask32 & OPT_o)
#define FLAG_F_force         (option_mask32 & OPT_F)
#define FLAG_W_warn_no_match (option_mask32 & OPT_W)
#define FLAG_c               (option_mask32 & OPT_c)
#define FLAG_R               (option_mask32 & OPT_R)


static void qprintf(const char *fmt UNUSED_PARAM, ...)
{
	/* quiet, do nothing */
}

static void inc_err(void)
{
	nerr++;
	if (nerr > 9 && !FLAG_d_debug) {
		bb_error_msg_and_die("exiting after 10 errors");
	}
}

static void add_exclude(const char *directory)
{
	struct stat sb;
	size_t len;

	if (directory == NULL || directory[0] != '/') {
		bb_error_msg_and_die("full path required for exclude: %s", directory);

	}
	if (lstat(directory, &sb)) {
		bb_error_msg("directory \"%s\" not found, ignoring", directory);
		return;
	}
	if ((sb.st_mode & S_IFDIR) == 0) {
		bb_error_msg("\"%s\" is not a directory: mode %o, ignoring",
			directory, sb.st_mode);
		return;
	}
	if (excludeCtr == MAX_EXCLUDES) {
		bb_error_msg_and_die("maximum excludes %d exceeded", MAX_EXCLUDES);
	}

	len = strlen(directory);
	while (len > 1 && directory[len - 1] == '/') {
		len--;
	}
	excludeArray[excludeCtr].directory = xstrndup(directory, len);
	excludeArray[excludeCtr++].size = len;
}

static bool exclude(const char *file)
{
	int i = 0;
	for (i = 0; i < excludeCtr; i++) {
		if (strncmp(file, excludeArray[i].directory,
					excludeArray[i].size) == 0) {
			if (file[excludeArray[i].size] == '\0'
			 || file[excludeArray[i].size] == '/') {
				return 1;
			}
		}
	}
	return 0;
}

static int match(const char *name, struct stat *sb, char **con)
{
	int ret;
	char path[PATH_MAX + 1];
	char *tmp_path = xstrdup(name);

	if (excludeCtr > 0 && exclude(name)) {
		goto err;
	}
	ret = lstat(name, sb);
	if (ret) {
		if (FLAG_i_ignore_enoent && errno == ENOENT) {
			free(tmp_path);
			return 0;
		}
		bb_error_msg("stat(%s)", name);
		goto err;
	}

	if (expand_realpath) {
		if (S_ISLNK(sb->st_mode)) {
			char *p = NULL;
			char *file_sep;

			size_t len = 0;

			if (verbose > 1)
				bb_error_msg("warning! %s refers to a symbolic link, not following last component", name);

			file_sep = strrchr(tmp_path, '/');
			if (file_sep == tmp_path) {
				file_sep++;
				path[0] = '\0';
				p = path;
			} else if (file_sep) {
				*file_sep++ = '\0';
				p = realpath(tmp_path, path);
			} else {
				file_sep = tmp_path;
				p = realpath("./", path);
			}
			if (p)
				len = strlen(p);
			if (!p || len + strlen(file_sep) + 2 > PATH_MAX) {
				bb_perror_msg("realpath(%s) failed", name);
				goto err;
			}
			p += len;
			/* ensure trailing slash of directory name */
			if (len == 0 || p[-1] != '/') {
				*p++ = '/';
			}
			strcpy(p, file_sep);
			name = path;
			if (excludeCtr > 0 && exclude(name))
				goto err;

		} else {
			char *p;
			p = realpath(name, path);
			if (!p) {
				bb_perror_msg("realpath(%s)", name);
				goto err;
			}
			name = p;
			if (excludeCtr > 0 && exclude(name))
				goto err;
		}
	}

	/* name will be what is matched in the policy */
	if (NULL != rootpath) {
		if (0 != strncmp(rootpath, name, rootpathlen)) {
			bb_error_msg("%s is not located in %s",
				name, rootpath);
			goto err;
		}
		name += rootpathlen;
	}

	free(tmp_path);
	if (rootpath != NULL && name[0] == '\0')
		/* this is actually the root dir of the alt root */
		return matchpathcon_index("/", sb->st_mode, con);
	return matchpathcon_index(name, sb->st_mode, con);
 err:
	free(tmp_path);
	return -1;
}

/* Compare two contexts to see if their differences are "significant",
 * or whether the only difference is in the user. */
static bool only_changed_user(const char *a, const char *b)
{
	if (FLAG_F_force)
		return 0;
	if (!a || !b)
		return 0;
	a = strchr(a, ':'); /* Rest of the context after the user */
	b = strchr(b, ':');
	if (!a || !b)
		return 0;
	return (strcmp(a, b) == 0);
}

static int restore(const char *file)
{
	char *my_file;
	struct stat my_sb;
	int i, j, ret;
	char *context = NULL;
	char *newcon = NULL;
	bool user_only_changed = 0;
	int retval = 0;

	my_file = bb_simplify_path(file);

	i = match(my_file, &my_sb, &newcon);

	if (i < 0) /* No matching specification. */
		goto out;

	if (FLAG_p_progress) {
		count++;
		if (count % 0x400 == 0) { /* every 1024 times */
			count = (count % (80*0x400));
			if (count == 0)
				bb_putchar('\n');
			bb_putchar('*');
			fflush_all();
		}
	}

	/*
	 * Try to add an association between this inode and
	 * this specification. If there is already an association
	 * for this inode and it conflicts with this specification,
	 * then use the last matching specification.
	 */
	if (add_assoc) {
		j = matchpathcon_filespec_add(my_sb.st_ino, i, my_file);
		if (j < 0)
			goto err;

		if (j != i) {
			/* There was already an association and it took precedence. */
			goto out;
		}
	}

	if (FLAG_d_debug)
		printf("%s: %s matched by %s\n", applet_name, my_file, newcon);

	/* Get the current context of the file. */
	ret = lgetfilecon_raw(my_file, &context);
	if (ret < 0) {
		if (errno == ENODATA) {
			context = NULL; /* paranoia */
		} else {
			bb_perror_msg("lgetfilecon_raw on %s", my_file);
			goto err;
		}
		user_only_changed = 0;
	} else
		user_only_changed = only_changed_user(context, newcon);

	/*
	 * Do not relabel the file if the matching specification is
	 * <<none>> or the file is already labeled according to the
	 * specification.
	 */
	if ((strcmp(newcon, "<<none>>") == 0)
	 || (context && (strcmp(context, newcon) == 0) && !FLAG_F_force)) {
		goto out;
	}

	if (!FLAG_F_force && context && (is_context_customizable(context) > 0)) {
		if (verbose > 1) {
			bb_error_msg("skipping %s. %s is customizable_types",
				my_file, context);
		}
		goto out;
	}

	if (verbose) {
		/* If we're just doing "-v", trim out any relabels where
		 * the user has changed but the role and type are the
		 * same.  For "-vv", emit everything. */
		if (verbose > 1 || !user_only_changed) {
			bb_info_msg("%s: reset %s context %s->%s",
				applet_name, my_file, context ? context : "", newcon);
		}
	}

	if (FLAG_l_take_log && !user_only_changed) {
		if (context)
			bb_info_msg("relabeling %s from %s to %s", my_file, context, newcon);
		else
			bb_info_msg("labeling %s to %s", my_file, newcon);
	}

	if (outfile && !user_only_changed)
		fprintf(outfile, "%s\n", my_file);

	/*
	 * Do not relabel the file if -n was used.
	 */
	if (FLAG_n_dry_run || user_only_changed)
		goto out;

	/*
	 * Relabel the file to the specified context.
	 */
	ret = lsetfilecon(my_file, newcon);
	if (ret) {
		bb_perror_msg("lsetfileconon(%s,%s)", my_file, newcon);
		goto err;
	}

 out:
	freecon(context);
	freecon(newcon);
	free(my_file);
	return retval;
 err:
	retval--; /* -1 */
	goto out;
}

/*
 * Apply the last matching specification to a file.
 * This function is called by recursive_action on each file during
 * the directory traversal.
 */
static int FAST_FUNC apply_spec(
		const char *file,
		struct stat *sb,
		void *userData UNUSED_PARAM,
		int depth UNUSED_PARAM)
{
	if (!follow_mounts) {
		/* setfiles does not process across different mount points */
		if (sb->st_dev != dev_id) {
			return SKIP;
		}
	}
	errors |= restore(file);
	if (abort_on_error && errors)
		return FALSE;
	return TRUE;
}


static int canoncon(const char *path, unsigned lineno, char **contextp)
{
	static const char err_msg[] ALIGN1 = "%s: line %u has invalid context %s";

	char *tmpcon;
	char *context = *contextp;
	int invalid = 0;

#if ENABLE_FEATURE_SETFILES_CHECK_OPTION
	if (policyfile) {
		if (sepol_check_context(context) >= 0)
			return 0;
		/* Exit immediately if we're in checking mode. */
		bb_error_msg_and_die(err_msg, path, lineno, context);
	}
#endif

	if (security_canonicalize_context_raw(context, &tmpcon) < 0) {
		if (errno != ENOENT) {
			invalid = 1;
			inc_err();
		}
	} else {
		free(context);
		*contextp = tmpcon;
	}

	if (invalid) {
		bb_error_msg(err_msg, path, lineno, context);
	}

	return invalid;
}

static int process_one(char *name)
{
	struct stat sb;
	int rc;

	rc = lstat(name, &sb);
	if (rc < 0) {
		if (FLAG_i_ignore_enoent && errno == ENOENT)
			return 0;
		bb_perror_msg("stat(%s)", name);
		goto err;
	}
	dev_id = sb.st_dev;

	if (S_ISDIR(sb.st_mode) && recurse) {
		if (recursive_action(name,
				     ACTION_RECURSE,
				     apply_spec,
				     apply_spec,
				     NULL, 0) != TRUE) {
			bb_error_msg("error while labeling %s", name);
			goto err;
		}
	} else {
		rc = restore(name);
		if (rc)
			goto err;
	}

 out:
	if (add_assoc) {
		if (FLAG_q_quiet)
			set_matchpathcon_printf(&qprintf);
		matchpathcon_filespec_eval();
		set_matchpathcon_printf(NULL);
		matchpathcon_filespec_destroy();
	}

	return rc;

 err:
	rc = -1;
	goto out;
}

int setfiles_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int setfiles_main(int argc UNUSED_PARAM, char **argv)
{
	struct stat sb;
	int rc, i = 0;
	const char *input_filename = NULL;
	char *buf = NULL;
	size_t buf_len;
	int flags;
	llist_t *exclude_dir = NULL;
	char *out_filename = NULL;

	INIT_G();

	if (applet_name[0] == 's') { /* "setfiles" */
		/*
		 * setfiles:
		 * Recursive descent,
		 * Does not expand paths via realpath,
		 * Aborts on errors during the file tree walk,
		 * Try to track inode associations for conflict detection,
		 * Does not follow mounts,
		 * Validates all file contexts at init time.
		 */
		recurse = 1;
		abort_on_error = 1;
		add_assoc = 1;
		/* follow_mounts = 0; - already is */
		matchpathcon_flags = MATCHPATHCON_VALIDATE | MATCHPATHCON_NOTRANS;
	} else {
		/*
		 * restorecon:
		 * No recursive descent unless -r/-R,
		 * Expands paths via realpath,
		 * Do not abort on errors during the file tree walk,
		 * Do not try to track inode associations for conflict detection,
		 * Follows mounts,
		 * Does lazy validation of contexts upon use.
		 */
		expand_realpath = 1;
		follow_mounts = 1;
		matchpathcon_flags = MATCHPATHCON_NOTRANS;
		/* restorecon only */
		selinux_or_die();
	}

	set_matchpathcon_flags(matchpathcon_flags);

	opt_complementary = "e::vv:v--p:p--v:v--q:q--v";
	/* Option order must match OPT_x definitions! */
	if (applet_name[0] == 'r') { /* restorecon */
		flags = getopt32(argv, "de:f:ilnpqrsvo:FWR",
			&exclude_dir, &input_filename, &out_filename, &verbose);
	} else { /* setfiles */
		flags = getopt32(argv, "de:f:ilnpqr:svo:FW"
				IF_FEATURE_SETFILES_CHECK_OPTION("c:"),
			&exclude_dir, &input_filename, &rootpath, &out_filename,
				 IF_FEATURE_SETFILES_CHECK_OPTION(&policyfile,)
			&verbose);
	}
	argv += optind;

#if ENABLE_FEATURE_SETFILES_CHECK_OPTION
	if ((applet_name[0] == 's') && (flags & OPT_c)) {
		FILE *policystream;

		policystream = xfopen_for_read(policyfile);
		if (sepol_set_policydb_from_file(policystream) < 0) {
			bb_error_msg_and_die("sepol_set_policydb_from_file on %s", policyfile);
		}
		fclose(policystream);

		/* Only process the specified file_contexts file, not
		   any .homedirs or .local files, and do not perform
		   context translations. */
		set_matchpathcon_flags(MATCHPATHCON_BASEONLY |
				       MATCHPATHCON_NOTRANS |
				       MATCHPATHCON_VALIDATE);
	}
#endif

	while (exclude_dir)
		add_exclude(llist_pop(&exclude_dir));

	if (flags & OPT_o) {
		outfile = stdout;
		if (NOT_LONE_CHAR(out_filename, '-')) {
			outfile = xfopen_for_write(out_filename);
		}
	}
	if (applet_name[0] == 'r') { /* restorecon */
		if (flags & (OPT_r | OPT_R))
			recurse = 1;
	} else { /* setfiles */
		if (flags & OPT_r)
			rootpathlen = strlen(rootpath);
	}
	if (flags & OPT_s) {
		input_filename = "-";
		add_assoc = 0;
	}

	if (applet_name[0] == 's') { /* setfiles */
		/* Use our own invalid context checking function so that
		   we can support either checking against the active policy or
		   checking against a binary policy file. */
		set_matchpathcon_canoncon(&canoncon);
		if (!argv[0])
			bb_show_usage();
		xstat(argv[0], &sb);
		if (!S_ISREG(sb.st_mode)) {
			bb_error_msg_and_die("spec file %s is not a regular file", argv[0]);
		}
		/* Load the file contexts configuration and check it. */
		rc = matchpathcon_init(argv[0]);
		if (rc < 0) {
			bb_simple_perror_msg_and_die(argv[0]);
		}
		if (nerr)
			exit(EXIT_FAILURE);
		argv++;
	}

	if (input_filename) {
		ssize_t len;
		FILE *f = stdin;

		if (NOT_LONE_CHAR(input_filename, '-'))
			f = xfopen_for_read(input_filename);
		while ((len = getline(&buf, &buf_len, f)) > 0) {
			buf[len - 1] = '\0';
			errors |= process_one(buf);
		}
		if (ENABLE_FEATURE_CLEAN_UP)
			fclose_if_not_stdin(f);
	} else {
		if (!argv[0])
			bb_show_usage();
		for (i = 0; argv[i]; i++) {
			errors |= process_one(argv[i]);
		}
	}

	if (FLAG_W_warn_no_match)
		matchpathcon_checkmatches(argv[0]);

	if (ENABLE_FEATURE_CLEAN_UP && outfile)
		fclose(outfile);

	return errors;
}
1	/*
2	setfiles: based on policycoreutils 2.0.19
3	policycoreutils was released under GPL 2.
4	Port to BusyBox (c) 2007 by Yuichi Nakamura <ynakam@hitachisoft.jp>
5	*/
6
7	#include "libbb.h"
8	#if ENABLE_FEATURE_SETFILES_CHECK_OPTION
9	#include <sepol/sepol.h>
10	#endif
11
12	#define MAX_EXCLUDES 50
13
14	struct edir {
15	char *directory;
16	size_t size;
17	};
18
19	struct globals {
20	FILE *outfile;
21	char *policyfile;
22	char *rootpath;
23	int rootpathlen;
24	unsigned count;
25	int excludeCtr;
26	int errors;
27	int verbose; /* getopt32 uses it, has to be int */
28	smallint recurse; /* Recursive descent */
29	smallint follow_mounts;
30	/* Behavior flags determined based on setfiles vs. restorecon */
31	smallint expand_realpath; /* Expand paths via realpath */
32	smallint abort_on_error; /* Abort the file tree walk upon an error */
33	int add_assoc; /* Track inode associations for conflict detection */
34	int matchpathcon_flags; /* Flags to matchpathcon */
35	dev_t dev_id; /* Device id where target file exists */
36	int nerr;
37	struct edir excludeArray[MAX_EXCLUDES];
38	} FIX_ALIASING;
39	#define G ((struct globals)&bb_common_bufsiz1)
40	void BUG_setfiles_globals_too_big(void);
41	#define INIT_G() do { \
42	if (sizeof(G) > COMMON_BUFSIZE) \
43	BUG_setfiles_globals_too_big(); \
44	/* memset(&G, 0, sizeof(G)); - already is */ \
45	} while (0)
46	#define outfile (G.outfile )
47	#define policyfile (G.policyfile )
48	#define rootpath (G.rootpath )
49	#define rootpathlen (G.rootpathlen )
50	#define count (G.count )
51	#define excludeCtr (G.excludeCtr )
52	#define errors (G.errors )
53	#define verbose (G.verbose )
54	#define recurse (G.recurse )
55	#define follow_mounts (G.follow_mounts )
56	#define expand_realpath (G.expand_realpath )
57	#define abort_on_error (G.abort_on_error )
58	#define add_assoc (G.add_assoc )
59	#define matchpathcon_flags (G.matchpathcon_flags)
60	#define dev_id (G.dev_id )
61	#define nerr (G.nerr )
62	#define excludeArray (G.excludeArray )
63
64	/* Must match getopt32 string! */
65	enum {
66	OPT_d = (1 << 0),
67	OPT_e = (1 << 1),
68	OPT_f = (1 << 2),
69	OPT_i = (1 << 3),
70	OPT_l = (1 << 4),
71	OPT_n = (1 << 5),
72	OPT_p = (1 << 6),
73	OPT_q = (1 << 7),
74	OPT_r = (1 << 8),
75	OPT_s = (1 << 9),
76	OPT_v = (1 << 10),
77	OPT_o = (1 << 11),
78	OPT_F = (1 << 12),
79	OPT_W = (1 << 13),
80	OPT_c = (1 << 14), /* c only for setfiles */
81	OPT_R = (1 << 14), /* R only for restorecon */
82	};
83	#define FLAG_d_debug (option_mask32 & OPT_d)
84	#define FLAG_e (option_mask32 & OPT_e)
85	#define FLAG_f (option_mask32 & OPT_f)
86	#define FLAG_i_ignore_enoent (option_mask32 & OPT_i)
87	#define FLAG_l_take_log (option_mask32 & OPT_l)
88	#define FLAG_n_dry_run (option_mask32 & OPT_n)
89	#define FLAG_p_progress (option_mask32 & OPT_p)
90	#define FLAG_q_quiet (option_mask32 & OPT_q)
91	#define FLAG_r (option_mask32 & OPT_r)
92	#define FLAG_s (option_mask32 & OPT_s)
93	#define FLAG_v (option_mask32 & OPT_v)
94	#define FLAG_o (option_mask32 & OPT_o)
95	#define FLAG_F_force (option_mask32 & OPT_F)
96	#define FLAG_W_warn_no_match (option_mask32 & OPT_W)
97	#define FLAG_c (option_mask32 & OPT_c)
98	#define FLAG_R (option_mask32 & OPT_R)
99
100
101	static void qprintf(const char *fmt UNUSED_PARAM, ...)
102	{
103	/* quiet, do nothing */
104	}
105
106	static void inc_err(void)
107	{
108	nerr++;
109	if (nerr > 9 && !FLAG_d_debug) {
110	bb_error_msg_and_die("exiting after 10 errors");
111	}
112	}
113
114	static void add_exclude(const char *directory)
115	{
116	struct stat sb;
117	size_t len;
118
119	if (directory == NULL \|\| directory[0] != '/') {
120	bb_error_msg_and_die("full path required for exclude: %s", directory);
121
122	}
123	if (lstat(directory, &sb)) {
124	bb_error_msg("directory \"%s\" not found, ignoring", directory);
125	return;
126	}
127	if ((sb.st_mode & S_IFDIR) == 0) {
128	bb_error_msg("\"%s\" is not a directory: mode %o, ignoring",
129	directory, sb.st_mode);
130	return;
131	}
132	if (excludeCtr == MAX_EXCLUDES) {
133	bb_error_msg_and_die("maximum excludes %d exceeded", MAX_EXCLUDES);
134	}
135
136	len = strlen(directory);
137	while (len > 1 && directory[len - 1] == '/') {
138	len--;
139	}
140	excludeArray[excludeCtr].directory = xstrndup(directory, len);
141	excludeArray[excludeCtr++].size = len;
142	}
143
144	static bool exclude(const char *file)
145	{
146	int i = 0;
147	for (i = 0; i < excludeCtr; i++) {
148	if (strncmp(file, excludeArray[i].directory,
149	excludeArray[i].size) == 0) {
150	if (file[excludeArray[i].size] == '\0'
151	\|\| file[excludeArray[i].size] == '/') {
152	return 1;
153	}
154	}
155	}
156	return 0;
157	}
158
159	static int match(const char name, struct stat sb, char **con)
160	{
161	int ret;
162	char path[PATH_MAX + 1];
163	char *tmp_path = xstrdup(name);
164
165	if (excludeCtr > 0 && exclude(name)) {
166	goto err;
167	}
168	ret = lstat(name, sb);
169	if (ret) {
170	if (FLAG_i_ignore_enoent && errno == ENOENT) {
171	free(tmp_path);
172	return 0;
173	}
174	bb_error_msg("stat(%s)", name);
175	goto err;
176	}
177
178	if (expand_realpath) {
179	if (S_ISLNK(sb->st_mode)) {
180	char *p = NULL;
181	char *file_sep;
182
183	size_t len = 0;
184
185	if (verbose > 1)
186	bb_error_msg("warning! %s refers to a symbolic link, not following last component", name);
187
188	file_sep = strrchr(tmp_path, '/');
189	if (file_sep == tmp_path) {
190	file_sep++;
191	path[0] = '\0';
192	p = path;
193	} else if (file_sep) {
194	*file_sep++ = '\0';
195	p = realpath(tmp_path, path);
196	} else {
197	file_sep = tmp_path;
198	p = realpath("./", path);
199	}
200	if (p)
201	len = strlen(p);
202	if (!p \|\| len + strlen(file_sep) + 2 > PATH_MAX) {
203	bb_perror_msg("realpath(%s) failed", name);
204	goto err;
205	}
206	p += len;
207	/* ensure trailing slash of directory name */
208	if (len == 0 \|\| p[-1] != '/') {
209	*p++ = '/';
210	}
211	strcpy(p, file_sep);
212	name = path;
213	if (excludeCtr > 0 && exclude(name))
214	goto err;
215
216	} else {
217	char *p;
218	p = realpath(name, path);
219	if (!p) {
220	bb_perror_msg("realpath(%s)", name);
221	goto err;
222	}
223	name = p;
224	if (excludeCtr > 0 && exclude(name))
225	goto err;
226	}
227	}
228
229	/* name will be what is matched in the policy */
230	if (NULL != rootpath) {
231	if (0 != strncmp(rootpath, name, rootpathlen)) {
232	bb_error_msg("%s is not located in %s",
233	name, rootpath);
234	goto err;
235	}
236	name += rootpathlen;
237	}
238
239	free(tmp_path);
240	if (rootpath != NULL && name[0] == '\0')
241	/* this is actually the root dir of the alt root */
242	return matchpathcon_index("/", sb->st_mode, con);
243	return matchpathcon_index(name, sb->st_mode, con);
244	err:
245	free(tmp_path);
246	return -1;
247	}
248
249	/* Compare two contexts to see if their differences are "significant",
250	* or whether the only difference is in the user. */
251	static bool only_changed_user(const char a, const char b)
252	{
253	if (FLAG_F_force)
254	return 0;
255	if (!a \|\| !b)
256	return 0;
257	a = strchr(a, ':'); /* Rest of the context after the user */
258	b = strchr(b, ':');
259	if (!a \|\| !b)
260	return 0;
261	return (strcmp(a, b) == 0);
262	}
263
264	static int restore(const char *file)
265	{
266	char *my_file;
267	struct stat my_sb;
268	int i, j, ret;
269	char *context = NULL;
270	char *newcon = NULL;
271	bool user_only_changed = 0;
272	int retval = 0;
273
274	my_file = bb_simplify_path(file);
275
276	i = match(my_file, &my_sb, &newcon);
277
278	if (i < 0) /* No matching specification. */
279	goto out;
280
281	if (FLAG_p_progress) {
282	count++;
283	if (count % 0x400 == 0) { /* every 1024 times */
284	count = (count % (80*0x400));
285	if (count == 0)
286	bb_putchar('\n');
287	bb_putchar('*');
288	fflush_all();
289	}
290	}
291
292	/*
293	* Try to add an association between this inode and
294	* this specification. If there is already an association
295	* for this inode and it conflicts with this specification,
296	* then use the last matching specification.
297	*/
298	if (add_assoc) {
299	j = matchpathcon_filespec_add(my_sb.st_ino, i, my_file);
300	if (j < 0)
301	goto err;
302
303	if (j != i) {
304	/* There was already an association and it took precedence. */
305	goto out;
306	}
307	}
308
309	if (FLAG_d_debug)
310	printf("%s: %s matched by %s\n", applet_name, my_file, newcon);
311
312	/* Get the current context of the file. */
313	ret = lgetfilecon_raw(my_file, &context);
314	if (ret < 0) {
315	if (errno == ENODATA) {
316	context = NULL; /* paranoia */
317	} else {
318	bb_perror_msg("lgetfilecon_raw on %s", my_file);
319	goto err;
320	}
321	user_only_changed = 0;
322	} else
323	user_only_changed = only_changed_user(context, newcon);
324
325	/*
326	* Do not relabel the file if the matching specification is
327	* <<none>> or the file is already labeled according to the
328	* specification.
329	*/
330	if ((strcmp(newcon, "<<none>>") == 0)
331	\|\| (context && (strcmp(context, newcon) == 0) && !FLAG_F_force)) {
332	goto out;
333	}
334
335	if (!FLAG_F_force && context && (is_context_customizable(context) > 0)) {
336	if (verbose > 1) {
337	bb_error_msg("skipping %s. %s is customizable_types",
338	my_file, context);
339	}
340	goto out;
341	}
342
343	if (verbose) {
344	/* If we're just doing "-v", trim out any relabels where
345	* the user has changed but the role and type are the
346	* same. For "-vv", emit everything. */
347	if (verbose > 1 \|\| !user_only_changed) {
348	bb_info_msg("%s: reset %s context %s->%s",
349	applet_name, my_file, context ? context : "", newcon);
350	}
351	}
352
353	if (FLAG_l_take_log && !user_only_changed) {
354	if (context)
355	bb_info_msg("relabeling %s from %s to %s", my_file, context, newcon);
356	else
357	bb_info_msg("labeling %s to %s", my_file, newcon);
358	}
359
360	if (outfile && !user_only_changed)
361	fprintf(outfile, "%s\n", my_file);
362
363	/*
364	* Do not relabel the file if -n was used.
365	*/
366	if (FLAG_n_dry_run \|\| user_only_changed)
367	goto out;
368
369	/*
370	* Relabel the file to the specified context.
371	*/
372	ret = lsetfilecon(my_file, newcon);
373	if (ret) {
374	bb_perror_msg("lsetfileconon(%s,%s)", my_file, newcon);
375	goto err;
376	}
377
378	out:
379	freecon(context);
380	freecon(newcon);
381	free(my_file);
382	return retval;
383	err:
384	retval--; /* -1 */
385	goto out;
386	}
387
388	/*
389	* Apply the last matching specification to a file.
390	* This function is called by recursive_action on each file during
391	* the directory traversal.
392	*/
393	static int FAST_FUNC apply_spec(
394	const char *file,
395	struct stat *sb,
396	void *userData UNUSED_PARAM,
397	int depth UNUSED_PARAM)
398	{
399	if (!follow_mounts) {
400	/* setfiles does not process across different mount points */
401	if (sb->st_dev != dev_id) {
402	return SKIP;
403	}
404	}
405	errors \|= restore(file);
406	if (abort_on_error && errors)
407	return FALSE;
408	return TRUE;
409	}
410
411
412	static int canoncon(const char path, unsigned lineno, char *contextp)
413	{
414	static const char err_msg[] ALIGN1 = "%s: line %u has invalid context %s";
415
416	char *tmpcon;
417	char context = contextp;
418	int invalid = 0;
419
420	#if ENABLE_FEATURE_SETFILES_CHECK_OPTION
421	if (policyfile) {
422	if (sepol_check_context(context) >= 0)
423	return 0;
424	/* Exit immediately if we're in checking mode. */
425	bb_error_msg_and_die(err_msg, path, lineno, context);
426	}
427	#endif
428
429	if (security_canonicalize_context_raw(context, &tmpcon) < 0) {
430	if (errno != ENOENT) {
431	invalid = 1;
432	inc_err();
433	}
434	} else {
435	free(context);
436	*contextp = tmpcon;
437	}
438
439	if (invalid) {
440	bb_error_msg(err_msg, path, lineno, context);
441	}
442
443	return invalid;
444	}
445
446	static int process_one(char *name)
447	{
448	struct stat sb;
449	int rc;
450
451	rc = lstat(name, &sb);
452	if (rc < 0) {
453	if (FLAG_i_ignore_enoent && errno == ENOENT)
454	return 0;
455	bb_perror_msg("stat(%s)", name);
456	goto err;
457	}
458	dev_id = sb.st_dev;
459
460	if (S_ISDIR(sb.st_mode) && recurse) {
461	if (recursive_action(name,
462	ACTION_RECURSE,
463	apply_spec,
464	apply_spec,
465	NULL, 0) != TRUE) {
466	bb_error_msg("error while labeling %s", name);
467	goto err;
468	}
469	} else {
470	rc = restore(name);
471	if (rc)
472	goto err;
473	}
474
475	out:
476	if (add_assoc) {
477	if (FLAG_q_quiet)
478	set_matchpathcon_printf(&qprintf);
479	matchpathcon_filespec_eval();
480	set_matchpathcon_printf(NULL);
481	matchpathcon_filespec_destroy();
482	}
483
484	return rc;
485
486	err:
487	rc = -1;
488	goto out;
489	}
490
491	int setfiles_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
492	int setfiles_main(int argc UNUSED_PARAM, char **argv)
493	{
494	struct stat sb;
495	int rc, i = 0;
496	const char *input_filename = NULL;
497	char *buf = NULL;
498	size_t buf_len;
499	int flags;
500	llist_t *exclude_dir = NULL;
501	char *out_filename = NULL;
502
503	INIT_G();
504
505	if (applet_name[0] == 's') { /* "setfiles" */
506	/*
507	* setfiles:
508	* Recursive descent,
509	* Does not expand paths via realpath,
510	* Aborts on errors during the file tree walk,
511	* Try to track inode associations for conflict detection,
512	* Does not follow mounts,
513	* Validates all file contexts at init time.
514	*/
515	recurse = 1;
516	abort_on_error = 1;
517	add_assoc = 1;
518	/* follow_mounts = 0; - already is */
519	matchpathcon_flags = MATCHPATHCON_VALIDATE \| MATCHPATHCON_NOTRANS;
520	} else {
521	/*
522	* restorecon:
523	* No recursive descent unless -r/-R,
524	* Expands paths via realpath,
525	* Do not abort on errors during the file tree walk,
526	* Do not try to track inode associations for conflict detection,
527	* Follows mounts,
528	* Does lazy validation of contexts upon use.
529	*/
530	expand_realpath = 1;
531	follow_mounts = 1;
532	matchpathcon_flags = MATCHPATHCON_NOTRANS;
533	/* restorecon only */
534	selinux_or_die();
535	}
536
537	set_matchpathcon_flags(matchpathcon_flags);
538
539	opt_complementary = "e::vv:v--p:p--v:v--q:q--v";
540	/* Option order must match OPT_x definitions! */
541	if (applet_name[0] == 'r') { /* restorecon */
542	flags = getopt32(argv, "de:f:ilnpqrsvo:FWR",
543	&exclude_dir, &input_filename, &out_filename, &verbose);
544	} else { /* setfiles */
545	flags = getopt32(argv, "de:f:ilnpqr:svo:FW"
546	IF_FEATURE_SETFILES_CHECK_OPTION("c:"),
547	&exclude_dir, &input_filename, &rootpath, &out_filename,
548	IF_FEATURE_SETFILES_CHECK_OPTION(&policyfile,)
549	&verbose);
550	}
551	argv += optind;
552
553	#if ENABLE_FEATURE_SETFILES_CHECK_OPTION
554	if ((applet_name[0] == 's') && (flags & OPT_c)) {
555	FILE *policystream;
556
557	policystream = xfopen_for_read(policyfile);
558	if (sepol_set_policydb_from_file(policystream) < 0) {
559	bb_error_msg_and_die("sepol_set_policydb_from_file on %s", policyfile);
560	}
561	fclose(policystream);
562
563	/* Only process the specified file_contexts file, not
564	any .homedirs or .local files, and do not perform
565	context translations. */
566	set_matchpathcon_flags(MATCHPATHCON_BASEONLY \|
567	MATCHPATHCON_NOTRANS \|
568	MATCHPATHCON_VALIDATE);
569	}
570	#endif
571
572	while (exclude_dir)
573	add_exclude(llist_pop(&exclude_dir));
574
575	if (flags & OPT_o) {
576	outfile = stdout;
577	if (NOT_LONE_CHAR(out_filename, '-')) {
578	outfile = xfopen_for_write(out_filename);
579	}
580	}
581	if (applet_name[0] == 'r') { /* restorecon */
582	if (flags & (OPT_r \| OPT_R))
583	recurse = 1;
584	} else { /* setfiles */
585	if (flags & OPT_r)
586	rootpathlen = strlen(rootpath);
587	}
588	if (flags & OPT_s) {
589	input_filename = "-";
590	add_assoc = 0;
591	}
592
593	if (applet_name[0] == 's') { /* setfiles */
594	/* Use our own invalid context checking function so that
595	we can support either checking against the active policy or
596	checking against a binary policy file. */
597	set_matchpathcon_canoncon(&canoncon);
598	if (!argv[0])
599	bb_show_usage();
600	xstat(argv[0], &sb);
601	if (!S_ISREG(sb.st_mode)) {
602	bb_error_msg_and_die("spec file %s is not a regular file", argv[0]);
603	}
604	/* Load the file contexts configuration and check it. */
605	rc = matchpathcon_init(argv[0]);
606	if (rc < 0) {
607	bb_simple_perror_msg_and_die(argv[0]);
608	}
609	if (nerr)
610	exit(EXIT_FAILURE);
611	argv++;
612	}
613
614	if (input_filename) {
615	ssize_t len;
616	FILE *f = stdin;
617
618	if (NOT_LONE_CHAR(input_filename, '-'))
619	f = xfopen_for_read(input_filename);
620	while ((len = getline(&buf, &buf_len, f)) > 0) {
621	buf[len - 1] = '\0';
622	errors \|= process_one(buf);
623	}
624	if (ENABLE_FEATURE_CLEAN_UP)
625	fclose_if_not_stdin(f);
626	} else {
627	if (!argv[0])
628	bb_show_usage();
629	for (i = 0; argv[i]; i++) {
630	errors \|= process_one(argv[i]);
631	}
632	}
633
634	if (FLAG_W_warn_no_match)
635	matchpathcon_checkmatches(argv[0]);
636
637	if (ENABLE_FEATURE_CLEAN_UP && outfile)
638	fclose(outfile);
639
640	return errors;
641	}