Magisk/native/jni/resetprop/resetprop.cpp
2019-02-12 05:17:02 -05:00

314 lines
8.0 KiB
C++

#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <dirent.h>
#include <sys/types.h>
#include <vector>
#include <algorithm>
#include <magisk.h>
#include <resetprop.h>
#include <utils.h>
#include <flags.h>
#define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_
#include "private/_system_properties.h"
#include "private/system_properties.h"
#include "_resetprop.h"
using namespace std;
bool use_pb = false;
static bool verbose = false;
static bool check_legal_property_name(const char *name) {
int namelen = strlen(name);
if (namelen < 1) goto illegal;
if (name[0] == '.') goto illegal;
if (name[namelen - 1] == '.') goto illegal;
/* Only allow alphanumeric, plus '.', '-', '@', ':', or '_' */
/* Don't allow ".." to appear in a property name */
for (size_t i = 0; i < namelen; i++) {
if (name[i] == '.') {
// i=0 is guaranteed to never have a dot. See above.
if (name[i-1] == '.') goto illegal;
continue;
}
if (name[i] == '_' || name[i] == '-' || name[i] == '@' || name[i] == ':') continue;
if (name[i] >= 'a' && name[i] <= 'z') continue;
if (name[i] >= 'A' && name[i] <= 'Z') continue;
if (name[i] >= '0' && name[i] <= '9') continue;
goto illegal;
}
return true;
illegal:
LOGE("Illegal property name: [%s]\n", name);
return false;
}
[[noreturn]] static void usage(char* arg0) {
fprintf(stderr,
FULL_VER(resetprop) " - System Props Modification Tool\n\n"
"Usage: %s [flags] [options...]\n"
"\n"
"Options:\n"
" -h, --help show this message\n"
" (no arguments) print all properties\n"
" NAME get property\n"
" NAME VALUE set property entry NAME with VALUE\n"
" --file FILE load props from FILE\n"
" --delete NAME delete property\n"
"\n"
"Flags:\n"
" -v print verbose output to stderr\n"
" -n set properties without init triggers\n"
" only affects setprop\n"
" -p access actual persist storage\n"
" only affects getprop and deleteprop\n"
"\n"
, arg0);
exit(1);
}
static void read_props(const prop_info *pi, void *read_cb) {
__system_property_read_callback(
pi, [](auto cb, auto name, auto value, auto) -> void
{
((read_cb_t *) cb)->exec(name, value);
}, read_cb);
}
void collect_props(const char *name, const char *value, void *v_plist) {
auto &prop_list = *static_cast<vector<prop_t> *>(v_plist);
prop_list.emplace_back(name, value);
}
static void collect_unique_props(const char *name, const char *value, void *v_plist) {
auto &prop_list = *static_cast<vector<prop_t> *>(v_plist);
for (auto &prop : prop_list) {
if (strcmp(name, prop.name) == 0)
return;
}
collect_props(name, value, v_plist);
}
static int init_resetprop() {
use_pb = use_pb ? true : access(PERSISTENT_PROPERTY_DIR "/persistent_properties", R_OK) == 0;
if (__system_properties_init()) {
LOGE("resetprop: Initialize error\n");
return -1;
}
return 0;
}
static void print_props(bool persist) {
vector<prop_t> prop_list;
getprop(collect_props, &prop_list, persist);
sort(prop_list.begin(), prop_list.end());
for (auto &prop : prop_list)
printf("[%s]: [%s]\n", prop.name, prop.value);
}
/* **************************************************
* Implementations of functions in resetprop.h (APIs)
* **************************************************/
int prop_exist(const char *name) {
if (init_resetprop()) return 0;
return __system_property_find(name) != nullptr;
}
// Get prop by name, return string
string getprop(const char *name, bool persist) {
if (!check_legal_property_name(name) || init_resetprop())
return string();
const prop_info *pi = __system_property_find(name);
if (pi == nullptr) {
if (persist && strncmp(name, "persist.", 8) == 0) {
auto value = persist_getprop(name);
if (value.empty())
LOGD("resetprop: prop [%s] does not exist\n", name);
return value;
}
return string();
} else {
char value[PROP_VALUE_MAX];
read_cb_t read_cb;
read_cb.cb = [](auto, auto value, auto dst) -> void { strcpy((char *) dst, value); };
read_cb.arg = value;
read_props(pi, &read_cb);
LOGD("resetprop: getprop [%s]: [%s]\n", name, value);
return value;
}
}
void getprop(void (*callback)(const char *, const char *, void *), void *cookie, bool persist) {
if (init_resetprop()) return;
read_cb_t read_cb(callback, cookie);
__system_property_foreach(read_props, &read_cb);
if (persist) {
read_cb.cb = collect_unique_props;
persist_getprop(&read_cb);
}
}
int setprop(const char *name, const char *value, bool trigger) {
if (!check_legal_property_name(name))
return 1;
if (init_resetprop())
return -1;
int ret;
auto pi = (prop_info*) __system_property_find(name);
if (pi != nullptr) {
if (trigger) {
if (strncmp(name, "ro.", 3) == 0) deleteprop(name);
ret = __system_property_set(name, value);
} else {
ret = __system_property_update(pi, value, strlen(value));
}
} else {
LOGD("resetprop: New prop [%s]\n", name);
if (trigger) {
ret = __system_property_set(name, value);
} else {
ret = __system_property_add(name, strlen(name), value, strlen(value));
}
}
LOGD("resetprop: setprop [%s]: [%s] by %s\n", name, value,
trigger ? "property_service" : "modifing prop data structure");
if (ret)
LOGE("resetprop: setprop error\n");
return ret;
}
int deleteprop(const char *name, bool persist) {
if (!check_legal_property_name(name))
return 1;
if (init_resetprop()) return -1;
char path[PATH_MAX];
path[0] = '\0';
LOGD("resetprop: deleteprop [%s]\n", name);
if (persist && strncmp(name, "persist.", 8) == 0)
persist = persist_deleteprop(name);
return __system_property_del(name) && !(persist && strncmp(name, "persist.", 8) == 0);
}
int parse_prop_file(const char *filename, const function<bool (const char *, const char *)> &cb) {
LOGD("resetprop: Parse prop file [%s]\n", filename);
FILE *fp = xfopen(filename, "re");
if (fp == nullptr) {
LOGE("Cannot open [%s]\n", filename);
return 1;
}
char *line = nullptr, *eql;
size_t len;
ssize_t read;
int i;
while ((read = getline(&line, &len, fp)) != -1) {
// Remove the trailing newline
if (line[read - 1] == '\n') {
line[--read] = '\0';
}
bool comment = false;
for (i = 0; i < read; ++i) {
// Ignore starting spaces
if (line[i] == ' ') continue;
// A line starting with # is ignored
if (line[i] == '#') comment = true;
break;
}
if (comment) continue;
eql = strchr(line, '=');
// Ignore invalid formats
if ( ((eql == nullptr) || (i >= (eql - line))) || (eql >= line + read - 1) )
continue;
// Separate the string
*eql = '\0';
if (!cb(line + i, eql + 1))
break;
}
free(line);
fclose(fp);
return 0;
}
int load_prop_file(const char *filename, bool trigger) {
if (init_resetprop()) return -1;
return parse_prop_file(filename, [=](auto key, auto val) -> bool {
setprop(key, val, trigger);
return true;
});
}
int resetprop_main(int argc, char *argv[]) {
log_cb.d = [](auto fmt, auto ap) -> int { return verbose ? vfprintf(stderr, fmt, ap) : 0; };
bool trigger = true, persist = false;
char *argv0 = argv[0];
string prop;
--argc;
++argv;
// Parse flags and -- options
while (argc && argv[0][0] == '-') {
for (int idx = 1; true; ++idx) {
switch (argv[0][idx]) {
case '-':
if (strcmp(argv[0], "--file") == 0 && argc == 2) {
return load_prop_file(argv[1], trigger);
} else if (strcmp(argv[0], "--delete") == 0 && argc == 2) {
return deleteprop(argv[1], persist);
} else if (strcmp(argv[0], "--help") == 0) {
usage(argv0);
}
case 'v':
verbose = true;
continue;
case 'p':
persist = true;
continue;
case 'n':
trigger = false;
continue;
case '\0':
break;
case 'h':
default:
usage(argv0);
}
break;
}
--argc;
++argv;
}
switch (argc) {
case 0:
print_props(persist);
return 0;
case 1:
prop = getprop(argv[0], persist);
if (prop.empty()) return 1;
printf("%s\n", prop.c_str());
return 0;
case 2:
return setprop(argv[0], argv[1], trigger);
default:
usage(argv0);
}
}