1 /* getprop.c - Get an Android system property
2 *
3 * Copyright 2015 The Android Open Source Project
4
5 USE_GETPROP(NEWTOY(getprop, ">2Z", TOYFLAG_USR|TOYFLAG_SBIN))
6
7 config GETPROP
8 bool "getprop"
9 default y
10 depends on TOYBOX_ON_ANDROID && TOYBOX_SELINUX
11 help
12 usage: getprop [NAME [DEFAULT]]
13
14 Gets an Android system property, or lists them all.
15 */
16
17 #define FOR_getprop
18 #include "toys.h"
19
20 #include <sys/system_properties.h>
21
22 #include <selinux/android.h>
23 #include <selinux/label.h>
24 #include <selinux/selinux.h>
25
GLOBALS(size_t size;char ** nv;struct selabel_handle * handle;)26 GLOBALS(
27 size_t size;
28 char **nv; // name/value pairs: even=name, odd=value
29 struct selabel_handle *handle;
30 )
31
32 static char *get_property_context(const char *property)
33 {
34 char *context = NULL;
35
36 if (selabel_lookup(TT.handle, &context, property, 1)) {
37 perror_exit("unable to lookup label for \"%s\"", property);
38 }
39 return context;
40 }
41
read_callback(void * unused,const char * name,const char * value)42 static void read_callback(void *unused, const char *name, const char *value)
43 {
44 if (!(TT.size&31)) TT.nv = xrealloc(TT.nv, (TT.size+32)*2*sizeof(char *));
45
46 TT.nv[2*TT.size] = xstrdup((char *)name);
47 if (toys.optflags & FLAG_Z) {
48 TT.nv[1+2*TT.size++] = get_property_context(name);
49 } else {
50 TT.nv[1+2*TT.size++] = xstrdup((char *)value);
51 }
52 }
53
add_property(const prop_info * pi,void * unused)54 static void add_property(const prop_info *pi, void *unused)
55 {
56 __system_property_read_callback(pi, read_callback, NULL);
57 }
58
59 // Needed to supress extraneous "Loaded property_contexts from" message
selinux_log_callback_local(int type,const char * fmt,...)60 static int selinux_log_callback_local(int type, const char *fmt, ...)
61 {
62 va_list ap;
63
64 if (type == SELINUX_INFO) return 0;
65 va_start(ap, fmt);
66 verror_msg((char *)fmt, 0, ap);
67 va_end(ap);
68 return 0;
69 }
70
getprop_main(void)71 void getprop_main(void)
72 {
73 if (toys.optflags & FLAG_Z) {
74 union selinux_callback cb;
75
76 cb.func_log = selinux_log_callback_local;
77 selinux_set_callback(SELINUX_CB_LOG, cb);
78 TT.handle = selinux_android_prop_context_handle();
79 if (!TT.handle) error_exit("unable to get selinux property context handle");
80 }
81
82 if (*toys.optargs) {
83 if (toys.optflags & FLAG_Z) {
84 char *context = get_property_context(*toys.optargs);
85
86 puts(context);
87 if (CFG_TOYBOX_FREE) free(context);
88 } else {
89 if (__system_property_get(*toys.optargs, toybuf) <= 0)
90 strcpy(toybuf, toys.optargs[1] ? toys.optargs[1] : "");
91 puts(toybuf);
92 }
93 } else {
94 size_t i;
95
96 if (__system_property_foreach(add_property, NULL))
97 error_exit("property_list");
98 qsort(TT.nv, TT.size, 2*sizeof(char *), qstrcmp);
99 for (i = 0; i<TT.size; i++) printf("[%s]: [%s]\n", TT.nv[i*2],TT.nv[1+i*2]);
100 if (CFG_TOYBOX_FREE) {
101 for (i = 0; i<TT.size; i++) {
102 free(TT.nv[i*2]);
103 free(TT.nv[1+i*2]);
104 }
105 free(TT.nv);
106 }
107 }
108 if (CFG_TOYBOX_FREE && (toys.optflags & FLAG_Z)) selabel_close(TT.handle);
109 }
110