Magisk/core/jni/magiskboot/ramdisk.c
2017-12-07 03:21:13 +08:00

333 lines
8.6 KiB
C

#include <stdio.h>
#include <unistd.h>
#include <sys/stat.h>
#include <utils.h>
#include <sys/mman.h>
#include <fcntl.h>
#include "magiskboot.h"
#include "cpio.h"
static void cpio_patch(struct vector *v, int keepverity, int keepforceencrypt) {
cpio_entry *f;
vec_for_each(v, f) {
if (!keepverity) {
if (strstr(f->filename, "fstab") != NULL && S_ISREG(f->mode)) {
patch_verity(&f->data, &f->filesize, 1);
} else if (strcmp(f->filename, "verity_key") == 0) {
fprintf(stderr, "Remove [verity_key]\n");
f->remove = 1;
}
}
if (!keepforceencrypt) {
if (strstr(f->filename, "fstab") != NULL && S_ISREG(f->mode)) {
patch_encryption(&f->data, &f->filesize);
}
}
}
}
#define STOCK_BOOT 0x0
#define MAGISK_PATCH 0x1
#define OTHER_PATCH 0x2
static int cpio_test(struct vector *v) {
int ret = STOCK_BOOT;
cpio_entry *f;
const char *OTHER_LIST[] = { "sbin/launch_daemonsu.sh", "sbin/su", "init.xposed.rc", "boot/sbin/launch_daemonsu.sh", NULL };
const char *MAGISK_LIST[] = { ".backup/.magisk", "init.magisk.rc", "overlay/init.magisk.rc", NULL };
vec_for_each(v, f) {
for (int i = 0; OTHER_LIST[i]; ++i) {
if (strcmp(f->filename, OTHER_LIST[i]) == 0) {
// Already find other files, abort
return OTHER_PATCH;
}
}
for (int i = 0; MAGISK_LIST[i]; ++i) {
if (strcmp(f->filename, MAGISK_LIST[i]) == 0)
ret = MAGISK_PATCH;
}
}
cpio_vec_destroy(v);
return ret;
}
static char *cpio_stocksha1(struct vector *v) {
cpio_entry *f;
char sha1[41];
vec_for_each(v, f) {
if (strcmp(f->filename, "init.magisk.rc") == 0
|| strcmp(f->filename, "overlay/init.magisk.rc") == 0) {
for (void *pos = f->data; pos < f->data + f->filesize; pos = strchr(pos + 1, '\n') + 1) {
if (memcmp(pos, "# STOCKSHA1=", 12) == 0) {
pos += 12;
memcpy(sha1, pos, 40);
sha1[40] = '\0';
return strdup(sha1);
}
}
} else if (strcmp(f->filename, ".backup/.sha1") == 0) {
return f->data;
}
}
return NULL;
}
static struct vector *cpio_backup(struct vector *v, const char *orig, const char *keepverity,
const char *keepforceencrypt, const char *sha1) {
struct vector o_body, *o = &o_body, *ret;
cpio_entry *m, *n, *rem, *cksm;
char buf[PATH_MAX];
int res, backup;
ret = xcalloc(sizeof(*ret), 1);
vec_init(o);
vec_init(ret);
m = xcalloc(sizeof(*m), 1);
m->filename = strdup(".backup");
m->mode = S_IFDIR;
vec_push_back(ret, m);
m = xcalloc(sizeof(*m), 1);
m->filename = strdup(".backup/.magisk");
m->mode = S_IFREG;
m->data = xmalloc(50);
snprintf(m->data, 50, "KEEPVERITY=%s\nKEEPFORCEENCRYPT=%s\n", keepverity, keepforceencrypt);
m->filesize = strlen(m->data) + 1;
vec_push_back(ret, m);
rem = xcalloc(sizeof(*rem), 1);
rem->filename = strdup(".backup/.rmlist");
rem->mode = S_IFREG;
vec_push_back(ret, rem);
if (sha1) {
fprintf(stderr, "Save SHA1: [%s] -> [.backup/.sha1]\n", sha1);
cksm = xcalloc(sizeof(*cksm), 1);
vec_push_back(ret, cksm);
cksm->filename = strdup(".backup/.sha1");
cksm->mode = S_IFREG;
cksm->data = strdup(sha1);
cksm->filesize = strlen(sha1) + 1;
}
parse_cpio(o, orig);
// Remove possible backups in original ramdisk
cpio_rm(o, 1, ".backup");
cpio_rm(v, 1, ".backup");
// Sort both vectors before comparing
vec_sort(v, cpio_cmp);
vec_sort(o, cpio_cmp);
// Start comparing
size_t i = 0, j = 0;
while(i != vec_size(o) || j != vec_size(v)) {
backup = 0;
if (i != vec_size(o) && j != vec_size(v)) {
m = vec_entry(o)[i];
n = vec_entry(v)[j];
res = strcmp(m->filename, n->filename);
} else if (i == vec_size(o)) {
n = vec_entry(v)[j];
res = 1;
} else if (j == vec_size(v)) {
m = vec_entry(o)[i];
res = -1;
}
if (res < 0) {
// Something is missing in new ramdisk, backup!
++i;
backup = 1;
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 = 1;
fprintf(stderr, "Backup mismatch entry: ");
} else {
// Someting new in ramdisk, record in rem
++j;
if (n->remove) continue;
rem->data = xrealloc(rem->data, rem->filesize + strlen(n->filename) + 1);
memcpy(rem->data + rem->filesize, n->filename, strlen(n->filename) + 1);
rem->filesize += strlen(n->filename) + 1;
fprintf(stderr, "Record new entry: [%s] -> [.backup/.rmlist]\n", n->filename);
}
if (backup) {
sprintf(buf, ".backup/%s", m->filename);
free(m->filename);
m->filename = strdup(buf);
fprintf(stderr, "[%s] -> [%s]\n", buf, m->filename);
vec_push_back(ret, m);
// NULL the original entry, so it won't be freed
vec_entry(o)[i - 1] = NULL;
}
}
if (rem->filesize == 0)
rem->remove = 1;
// Cleanup
cpio_vec_destroy(o);
return ret;
}
static void cpio_restore(struct vector *v) {
cpio_entry *f, *n;
vec_for_each(v, f) {
if (strncmp(f->filename, ".backup", 7) == 0) {
f->remove = 1;
if (f->filename[7] == '\0') continue;
if (f->filename[8] == '.') {
if (strcmp(f->filename, ".backup/.rmlist") == 0) {
for (int pos = 0; pos < f->filesize; pos += strlen(f->data + pos) + 1)
cpio_rm(v, 0, f->data + pos);
}
continue;
} else {
n = xcalloc(sizeof(*n), 1);
memcpy(n, f, sizeof(*f));
n->filename = strdup(f->filename + 8);
n->data = f->data;
f->data = NULL;
n->remove = 0;
fprintf(stderr, "Restore [%s] -> [%s]\n", f->filename, n->filename);
cpio_vec_insert(v, n);
}
}
if (strncmp(f->filename, "overlay", 7) == 0)
f->remove = 1;
}
// Some known stuff we can remove
cpio_rm(v, 0, "sbin/magic_mask.sh");
cpio_rm(v, 0, "init.magisk.rc");
cpio_rm(v, 0, "magisk");
cpio_rm(v, 0, "ramdisk-recovery.xz");
}
static void restore_high_compress(struct vector *v, const char *incpio) {
// Check if the ramdisk is in high compression mode
if (cpio_extract(v, "ramdisk.cpio.xz", incpio) == 0) {
void *xz;
size_t size;
full_read(incpio, &xz, &size);
int fd = creat(incpio, 0644);
lzma(0, fd, xz, size);
close(fd);
free(xz);
cpio_rm(v, 0, "ramdisk.cpio.xz");
cpio_rm(v, 0, "init");
struct vector vv;
vec_init(&vv);
parse_cpio(&vv, incpio);
cpio_entry *e;
vec_for_each(&vv, e)
vec_push_back(v, e);
vec_destroy(&vv);
}
}
static void enable_high_compress(struct vector *v, struct vector *b, const char *incpio) {
cpio_entry *e, *magiskinit, *init;
// Swap magiskinit with original init
vec_for_each(b, e) {
if (strcmp(e->filename, ".backup/init") == 0) {
free(e->filename);
e->filename = strdup("init");
init = e;
vec_for_each(v, e) {
if (strcmp(e->filename, "init") == 0) {
magiskinit = e;
vec_cur(v) = init;
break;
}
}
vec_cur(b) = NULL;
break;
}
}
dump_cpio(v, incpio);
cpio_vec_destroy(v);
void *cpio;
size_t size;
full_read(incpio, &cpio, &size);
int fd = creat(incpio, 0644);
lzma(1, fd, cpio, size);
close(fd);
free(cpio);
vec_init(v);
vec_push_back(v, magiskinit);
cpio_add(v, 0, "ramdisk.cpio.xz", incpio);
}
int cpio_commands(const char *command, int argc, char *argv[]) {
char *incpio = argv[0];
++argv;
--argc;
struct vector v;
vec_init(&v);
parse_cpio(&v, incpio);
if (strcmp(command, "test") == 0) {
exit(cpio_test(&v));
} else if (strcmp(command, "restore") == 0) {
restore_high_compress(&v, incpio);
cpio_restore(&v);
} else if (strcmp(command, "stocksha1") == 0) {
printf("%s\n", cpio_stocksha1(&v));
return 0;
} else if (argc >= 4 && strcmp(command, "backup") == 0) {
struct vector *back;
cpio_entry *e;
back = cpio_backup(&v, argv[0], argv[2], argv[3], argc > 4 ? argv[4] : NULL);
// Enable high compression mode
if (strcmp(argv[1], "true") == 0)
enable_high_compress(&v, back, incpio);
vec_for_each(back, e)
if (e) vec_push_back(&v, e);
} else if (argc > 0 && strcmp(command, "rm") == 0) {
int recursive = 0;
if (argc == 2 && strcmp(argv[0], "-r") == 0) {
recursive = 1;
++argv;
}
cpio_rm(&v, recursive, argv[0]);
} else if (argc == 2 && strcmp(command, "mv") == 0) {
if (cpio_mv(&v, argv[0], argv[1]))
return 1;
} else if (argc == 2 && strcmp(command, "patch") == 0) {
cpio_patch(&v, strcmp(argv[0], "true") == 0, strcmp(argv[1], "true") == 0);
} else if (strcmp(command, "extract") == 0) {
if (argc == 2) {
return cpio_extract(&v, argv[0], argv[1]);
} else {
cpio_extract_all(&v);
return 0;
}
} else if (argc == 2 && strcmp(command, "mkdir") == 0) {
cpio_mkdir(&v, strtoul(argv[0], NULL, 8), argv[1]);
} else if (argc == 2 && strcmp(command, "ln") == 0) {
cpio_ln(&v, argv[0], argv[1]);
} else if (argc == 3 && strcmp(command, "add") == 0) {
cpio_add(&v, strtoul(argv[0], NULL, 8), argv[1], argv[2]);
} else {
return 1;
}
dump_cpio(&v, incpio);
cpio_vec_destroy(&v);
exit(0);
}