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,unsigned serial)42 static void read_callback(void *unused, const char *name, const char *value,
43 unsigned serial)
44 {
45 if (!(TT.size&31)) TT.nv = xrealloc(TT.nv, (TT.size+32)*2*sizeof(char *));
46
47 TT.nv[2*TT.size] = xstrdup((char *)name);
48 if (toys.optflags & FLAG_Z) {
49 TT.nv[1+2*TT.size++] = get_property_context(name);
50 } else {
51 TT.nv[1+2*TT.size++] = xstrdup((char *)value);
52 }
53 }
54
add_property(const prop_info * pi,void * unused)55 static void add_property(const prop_info *pi, void *unused)
56 {
57 __system_property_read_callback(pi, read_callback, NULL);
58 }
59
print_callback(void * unused,const char * unused_name,const char * value,unsigned unused_serial)60 static void print_callback(void *unused, const char *unused_name, const char *value,
61 unsigned unused_serial)
62 {
63 puts(value);
64 }
65
66 // Needed to supress extraneous "Loaded property_contexts from" message
selinux_log_callback_local(int type,const char * fmt,...)67 static int selinux_log_callback_local(int type, const char *fmt, ...)
68 {
69 va_list ap;
70
71 if (type == SELINUX_INFO) return 0;
72 va_start(ap, fmt);
73 verror_msg((char *)fmt, 0, ap);
74 va_end(ap);
75 return 0;
76 }
77
getprop_main(void)78 void getprop_main(void)
79 {
80 if (toys.optflags & FLAG_Z) {
81 union selinux_callback cb;
82
83 cb.func_log = selinux_log_callback_local;
84 selinux_set_callback(SELINUX_CB_LOG, cb);
85 TT.handle = selinux_android_prop_context_handle();
86 if (!TT.handle) error_exit("unable to get selinux property context handle");
87 }
88
89 if (*toys.optargs) {
90 if (toys.optflags & FLAG_Z) {
91 char *context = get_property_context(*toys.optargs);
92
93 puts(context);
94 if (CFG_TOYBOX_FREE) free(context);
95 } else {
96 const prop_info* pi = __system_property_find(*toys.optargs);
97 if (pi == NULL) {
98 puts(toys.optargs[1] ? toys.optargs[1] : "");
99 } else {
100 __system_property_read_callback(pi, print_callback, NULL);
101 }
102 }
103 } else {
104 size_t i;
105
106 if (__system_property_foreach(add_property, NULL))
107 error_exit("property_list");
108 qsort(TT.nv, TT.size, 2*sizeof(char *), qstrcmp);
109 for (i = 0; i<TT.size; i++) printf("[%s]: [%s]\n", TT.nv[i*2],TT.nv[1+i*2]);
110 if (CFG_TOYBOX_FREE) {
111 for (i = 0; i<TT.size; i++) {
112 free(TT.nv[i*2]);
113 free(TT.nv[1+i*2]);
114 }
115 free(TT.nv);
116 }
117 }
118 if (CFG_TOYBOX_FREE && (toys.optflags & FLAG_Z)) selabel_close(TT.handle);
119 }
120