Magisk/native/jni/magiskboot/ramdisk.cpp
2019-01-19 23:59:37 -05:00

268 lines
6.6 KiB
C++

#include <string.h>
#include <stdlib.h>
#include <sys/stat.h>
#include "magiskboot.h"
#include "cpio.h"
#include "utils.h"
using namespace std;
class magisk_cpio : public cpio {
public:
explicit magisk_cpio(const char *filename) : cpio(filename) {}
void patch(bool keepverity, bool keepforceencrypt);
int test();
char * sha1();
void restore();
void backup(const char *orig);
};
void magisk_cpio::patch(bool keepverity, bool keepforceencrypt) {
fprintf(stderr, "Patch with flag KEEPVERITY=[%s] KEEPFORCEENCRYPT=[%s]\n",
keepverity ? "true" : "false", keepforceencrypt ? "true" : "false");
for (auto &e : arr) {
if (!e)
continue;
bool fstab = (!keepverity || !keepforceencrypt) &&
!str_starts(e->filename, ".backup") &&
str_contains(e->filename, "fstab") && S_ISREG(e->mode);
if (!keepverity) {
if (fstab) {
patch_verity(&e->data, &e->filesize, 1);
} else if (e->filename == "verity_key") {
fprintf(stderr, "Remove [verity_key]\n");
delete e;
e = nullptr;
continue;
}
}
if (!keepforceencrypt) {
if (fstab) {
patch_encryption(&e->data, &e->filesize);
}
}
}
}
#define STOCK_BOOT 0x0
#define MAGISK_PATCH 0x1
#define UNSUPPORT_PATCH 0x2
int magisk_cpio::test() {
static const char *UNSUPPORT_LIST[] = { "sbin/launch_daemonsu.sh", "sbin/su", "init.xposed.rc",
"boot/sbin/launch_daemonsu.sh" };
static const char *MAGISK_LIST[] = { ".backup/.magisk", "init.magisk.rc",
"overlay/init.magisk.rc" };
for (auto file : UNSUPPORT_LIST)
if (find(file) >= 0)
return UNSUPPORT_PATCH;
for (auto file : MAGISK_LIST)
if (find(file) >= 0)
return MAGISK_PATCH;
return STOCK_BOOT;
}
#define for_each_line(line, buf, size) \
for (line = (char *) buf; line < (char *) buf + size && line[0]; line = strchr(line + 1, '\n') + 1)
char *magisk_cpio::sha1() {
char sha1[41];
char *line;
for (auto &e : arr) {
if (!e) continue;
if (e->filename == "init.magisk.rc" || e->filename == "overlay/init.magisk.rc") {
for_each_line(line, e->data, e->filesize) {
if (strncmp(line, "#STOCKSHA1=", 11) == 0) {
strncpy(sha1, line + 12, 40);
sha1[40] = '\0';
return strdup(sha1);
}
}
} else if (e->filename == ".backup/.magisk") {
for_each_line(line, e->data, e->filesize) {
if (strncmp(line, "SHA1=", 5) == 0) {
strncpy(sha1, line + 5, 40);
sha1[40] = '\0';
return strdup(sha1);
}
}
} else if (e->filename == ".backup/.sha1") {
return (char *) e->data;
}
}
return nullptr;
}
void magisk_cpio::restore() {
for (auto &e : arr) {
if (!e) continue;
if (str_starts(e->filename, ".backup")) {
if (e->filename[7] == '\0') continue;
if (e->filename[8] == '.') {
if (strcmp(&e->filename[8], ".rmlist") == 0) {
for (int pos = 0; pos < e->filesize; pos += strlen((char *) e->data + pos) + 1)
rm((char *) e->data + pos, false);
}
} else {
mv(e->filename.c_str(), &e->filename[8]);
}
}
}
// Some known stuff we can remove
rm(".backup", true);
rm("overlay", true);
rm("sbin/magic_mask.sh", false);
rm("init.magisk.rc", false);
rm("magisk", true);
}
void magisk_cpio::backup(const char *orig) {
vector<cpio_entry*> bak;
cpio_entry *m, *n, *rem;
char buf[PATH_MAX];
m = new cpio_entry(".backup");
m->mode = S_IFDIR;
bak.push_back(m);
rem = new cpio_entry(".backup/.rmlist");
rem->mode = S_IFREG;
magisk_cpio o(orig);
// Remove possible backups in original ramdisk
o.rm(".backup", true);
rm(".backup", true);
// Sort both CPIOs before comparing
o.sort();
sort();
// Start comparing
size_t i = 0, j = 0;
while(i != o.arr.size() || j != arr.size()) {
int res;
bool backup = false;
if (i != o.arr.size() && j != arr.size()) {
m = o.arr[i];
n = arr[j];
res = m->filename.compare(n->filename);
} else if (i == o.arr.size()) {
n = arr[j];
res = 1;
} else if (j == arr.size()) {
m = o.arr[i];
res = -1;
}
if (res < 0) {
// Something is missing in new ramdisk, backup!
++i;
backup = true;
fprintf(stderr, "Backup missing entry: ");
} else if (res == 0) {
++i; ++j;
if (m->filesize == n->filesize && memcmp(m->data, n->data, m->filesize) == 0)
continue;
// Not the same!
backup = true;
fprintf(stderr, "Backup mismatch entry: ");
} else {
// Something new in ramdisk, record in rem
++j;
rem->data = xrealloc(rem->data, rem->filesize + n->filename.size());
memcpy((char *) rem->data + rem->filesize, n->filename.c_str(), n->filename.size());
rem->filesize += n->filename.size();
fprintf(stderr, "Record new entry: [%s] -> [.backup/.rmlist]\n", n->filename.c_str());
}
if (backup) {
sprintf(buf, ".backup/%s", m->filename.c_str());
fprintf(stderr, "[%s] -> [%s]\n", m->filename.c_str(), buf);
m->filename = buf;
bak.push_back(m);
// NULL the original entry, so it won't be freed
o.arr[i - 1] = nullptr;
}
}
if (rem->filesize)
bak.push_back(rem);
else
delete rem;
if (bak.size() > 1)
for (auto item : bak)
insert(item);
}
int cpio_commands(int argc, char *argv[]) {
char *incpio = argv[0];
++argv;
--argc;
magisk_cpio cpio(incpio);
int cmdc;
char *cmdv[6];
while (argc) {
// Clean up
cmdc = 0;
memset(cmdv, NULL, sizeof(cmdv));
// Split the commands
for (char *tok = strtok(argv[0], " "); tok; tok = strtok(nullptr, " "))
cmdv[cmdc++] = tok;
if (cmdc == 0)
continue;
if (strcmp(cmdv[0], "test") == 0) {
exit(cpio.test());
} else if (strcmp(cmdv[0], "restore") == 0) {
cpio.restore();
} else if (strcmp(cmdv[0], "sha1") == 0) {
char *sha1 = cpio.sha1();
if (sha1) printf("%s\n", sha1);
return 0;
} else if (cmdc == 2 && strcmp(cmdv[0], "exists") == 0) {
exit(cpio.find(cmdv[1]) < 0);
} else if (cmdc == 2 && strcmp(cmdv[0], "backup") == 0) {
cpio.backup(cmdv[1]);
} else if (cmdc >= 2 && strcmp(cmdv[0], "rm") == 0) {
bool r = cmdc > 2 && strcmp(cmdv[1], "-r") == 0;
cpio.rm(cmdv[1 + r], r);
} else if (cmdc == 3 && strcmp(cmdv[0], "mv") == 0) {
cpio.mv(cmdv[1], cmdv[2]);
} else if (cmdc == 3 && strcmp(cmdv[0], "patch") == 0) {
cpio.patch(strcmp(cmdv[1], "true") == 0, strcmp(cmdv[2], "true") == 0);
} else if (strcmp(cmdv[0], "extract") == 0) {
if (cmdc == 3) {
return !cpio.extract(cmdv[1], cmdv[2]);
} else {
cpio.extract();
return 0;
}
} else if (cmdc == 3 && strcmp(cmdv[0], "mkdir") == 0) {
cpio.makedir(strtoul(cmdv[1], nullptr, 8), cmdv[2]);
} else if (cmdc == 3 && strcmp(cmdv[0], "ln") == 0) {
cpio.ln(cmdv[1], cmdv[2]);
} else if (cmdc == 4 && strcmp(cmdv[0], "add") == 0) {
cpio.add(strtoul(cmdv[1], nullptr, 8), cmdv[2], cmdv[3]);
} else {
return 1;
}
--argc;
++argv;
}
cpio.dump(incpio);
return 0;
}