Magisk/jni/magiskboot/cpio.c
2017-11-10 01:51:41 +08:00

542 lines
14 KiB
C

#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include "magiskboot.h"
#include "cpio.h"
#include "logging.h"
#include "utils.h"
static uint32_t x8u(char *hex) {
uint32_t val, inpos = 8, outpos;
char pattern[6];
while (*hex == '0') {
hex++;
if (!--inpos) return 0;
}
// Because scanf gratuitously treats %*X differently than printf does.
sprintf(pattern, "%%%dx%%n", inpos);
sscanf(hex, pattern, &val, &outpos);
if (inpos != outpos) LOGE("bad cpio header\n");
return val;
}
static void cpio_free(cpio_entry *f) {
if (f) {
free(f->filename);
free(f->data);
free(f);
}
}
static void cpio_vec_insert(struct vector *v, cpio_entry *n) {
cpio_entry *f;
vec_for_each(v, f) {
if (strcmp(f->filename, n->filename) == 0) {
// Replace, then all is done
cpio_free(f);
vec_cur(v) = n;
return;
}
}
vec_push_back(v, n);
}
static int cpio_cmp(const void *a, const void *b) {
return strcmp((*(cpio_entry **) a)->filename, (*(cpio_entry **) b)->filename);
}
// Parse cpio file to a vector of cpio_entry
static void parse_cpio(const char *filename, struct vector *v) {
fprintf(stderr, "Loading cpio: [%s]\n\n", filename);
int fd = xopen(filename, O_RDONLY);
cpio_newc_header header;
cpio_entry *f;
while(xxread(fd, &header, 110) != -1) {
f = xcalloc(sizeof(*f), 1);
// f->ino = x8u(header.ino);
f->mode = x8u(header.mode);
f->uid = x8u(header.uid);
f->gid = x8u(header.gid);
// f->nlink = x8u(header.nlink);
// f->mtime = x8u(header.mtime);
f->filesize = x8u(header.filesize);
// f->devmajor = x8u(header.devmajor);
// f->devminor = x8u(header.devminor);
// f->rdevmajor = x8u(header.rdevmajor);
// f->rdevminor = x8u(header.rdevminor);
f->namesize = x8u(header.namesize);
// f->check = x8u(header.check);
f->filename = xmalloc(f->namesize);
xxread(fd, f->filename, f->namesize);
file_align(fd, 4, 0);
if (strcmp(f->filename, ".") == 0 || strcmp(f->filename, "..") == 0) {
cpio_free(f);
continue;
}
if (strcmp(f->filename, "TRAILER!!!") == 0) {
cpio_free(f);
break;
}
if (f->filesize) {
f->data = malloc(f->filesize);
xxread(fd, f->data, f->filesize);
file_align(fd, 4, 0);
}
vec_push_back(v, f);
}
close(fd);
}
static void dump_cpio(const char *filename, struct vector *v) {
fprintf(stderr, "\nDump cpio: [%s]\n\n", filename);
int fd = creat(filename, 0644);
unsigned inode = 300000;
char header[111];
// Sort by name
vec_sort(v, cpio_cmp);
cpio_entry *f;
vec_for_each(v, f) {
if (f->remove) continue;
sprintf(header, "070701%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x",
inode++, // f->ino
f->mode,
f->uid,
f->gid,
1, // f->nlink
0, // f->mtime
f->filesize,
0, // f->devmajor
0, // f->devminor
0, // f->rdevmajor
0, // f->rdevminor
f->namesize,
0 // f->check
);
xwrite(fd, header, 110);
xwrite(fd, f->filename, f->namesize);
file_align(fd, 4, 1);
if (f->filesize) {
xwrite(fd, f->data, f->filesize);
file_align(fd, 4, 1);
}
}
// Write trailer
sprintf(header, "070701%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x%08x", inode++, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 11, 0);
xwrite(fd, header, 110);
xwrite(fd, "TRAILER!!!\0", 11);
file_align(fd, 4, 1);
close(fd);
}
static void cpio_vec_destroy(struct vector *v) {
// Free each cpio_entry
cpio_entry *f;
vec_for_each(v, f) {
cpio_free(f);
}
vec_destroy(v);
}
static void cpio_rm(int recursive, const char *entry, struct vector *v) {
cpio_entry *f;
vec_for_each(v, f) {
if (strncmp(f->filename, entry, strlen(entry)) == 0) {
char next = f->filename[strlen(entry)];
if ((recursive && next == '/') || next == '\0') {
if (!f->remove) {
fprintf(stderr, "Remove [%s]\n", f->filename);
f->remove = 1;
}
if (!recursive) return;
}
}
}
}
static void cpio_mkdir(mode_t mode, const char *entry, struct vector *v) {
cpio_entry *f = xcalloc(sizeof(*f), 1);
f->mode = S_IFDIR | mode;
f->namesize = strlen(entry) + 1;
f->filename = strdup(entry);
cpio_vec_insert(v, f);
fprintf(stderr, "Create directory [%s] (%04o)\n",entry, mode);
}
static void cpio_add(mode_t mode, const char *entry, const char *filename, struct vector *v) {
int fd = xopen(filename, O_RDONLY);
cpio_entry *f = xcalloc(sizeof(*f), 1);
f->mode = S_IFREG | mode;
f->namesize = strlen(entry) + 1;
f->filename = strdup(entry);
f->filesize = lseek(fd, 0, SEEK_END);
lseek(fd, 0, SEEK_SET);
f->data = xmalloc(f->filesize);
xxread(fd, f->data, f->filesize);
close(fd);
cpio_vec_insert(v, f);
fprintf(stderr, "Add entry [%s] (%04o)\n", entry, mode);
}
static void cpio_test(struct vector *v) {
#define STOCK_BOOT 0x0
#define MAGISK_PATCH 0x1
#define OTHER_PATCH 0x2
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) {
ret |= OTHER_PATCH;
// Already find other files, abort
exit(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);
exit(ret);
}
int check_verity_pattern(const char *s) {
int pos = 0;
if (s[0] == ',') ++pos;
if (strncmp(s + pos, "verify", 6) != 0) return -1;
pos += 6;
if (s[pos] == '=') {
while (s[pos] != '\0' && s[pos] != ' ' && s[pos] != '\n' && s[pos] != ',') ++pos;
}
return pos;
}
int check_encryption_pattern(const char *s) {
const char *encrypt_list[] = { "forceencrypt", "forcefdeorfbe", NULL };
for (int i = 0 ; encrypt_list[i]; ++i) {
int len = strlen(encrypt_list[i]);
if (strncmp(s, encrypt_list[i], len) == 0)
return len;
}
return -1;
}
static void cpio_patch(struct vector *v, int keepverity, int keepforceencrypt) {
cpio_entry *f;
int skip, write;
vec_for_each(v, f) {
if (!keepverity) {
if (strstr(f->filename, "fstab") != NULL && S_ISREG(f->mode)) {
write = 0;
for (int read = 0; read < f->filesize; ++write, ++read) {
if ((skip = check_verity_pattern(f->data + read)) > 0) {
fprintf(stderr, "Remove pattern [%.*s] in [%s]\n", skip, f->data + read, f->filename);
read += skip;
}
f->data[write] = f->data[read];
}
f->filesize = write;
} 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)) {
write = 0;
for (int read = 0; read < f->filesize; ++write, ++read) {
if ((skip = check_encryption_pattern(f->data + read)) > 0) {
// assert(skip > 11)!
fprintf(stderr, "Replace pattern [%.*s] with [encryptable] in [%s]\n", skip, f->data + read, f->filename);
memcpy(f->data + write, "encryptable", 11);
write += 11;
read += skip;
}
f->data[write] = f->data[read];
}
f->filesize = write;
}
}
}
}
static void cpio_extract(const char *entry, const char *filename, struct vector *v) {
cpio_entry *f;
vec_for_each(v, f) {
if (strcmp(f->filename, entry) == 0 && S_ISREG(f->mode)) {
fprintf(stderr, "Extracting [%s] to [%s]\n\n", entry, filename);
int fd = creat(filename, 0644);
xwrite(fd, f->data, f->filesize);
fchmod(fd, f->mode);
fchown(fd, f->uid, f->gid);
close(fd);
exit(0);
}
}
LOGE("Cannot find the file entry [%s]\n", entry);
}
static void cpio_backup(const char *orig, const char *sha1, struct vector *v) {
struct vector o_body, *o = &o_body, bak;
cpio_entry *m, *n, *rem, *cksm;
char buf[PATH_MAX];
int res, doBak;
if (sha1) cksm = xcalloc(sizeof(*cksm), 1);
vec_init(o);
vec_init(&bak);
m = xcalloc(sizeof(*m), 1);
m->filename = strdup(".backup");
m->namesize = strlen(m->filename) + 1;
m->mode = S_IFDIR;
vec_push_back(&bak, m);
m = xcalloc(sizeof(*m), 1);
m->filename = strdup(".backup/.magisk");
m->namesize = strlen(m->filename) + 1;
m->mode = S_IFREG;
vec_push_back(&bak, m);
rem = xcalloc(sizeof(*rem), 1);
rem->filename = strdup(".backup/.rmlist");
rem->namesize = strlen(rem->filename) + 1;
rem->mode = S_IFREG;
vec_push_back(&bak, rem);
if (sha1) vec_push_back(&bak, cksm);
parse_cpio(orig, o);
// Remove possible backups in original ramdisk
cpio_rm(1, ".backup", o);
cpio_rm(1, ".backup", v);
// Sort both vectors before comparing
vec_sort(v, cpio_cmp);
vec_sort(o, cpio_cmp);
if (sha1) {
fprintf(stderr, "Save SHA1: [%s] -> [.backup/.sha1]\n", sha1);
cksm->filename = strdup(".backup/.sha1");
cksm->namesize = strlen(cksm->filename) + 1;
cksm->mode = S_IFREG;
cksm->data = strdup(sha1);
cksm->filesize = strlen(sha1) + 1;
}
// Start comparing
size_t i = 0, j = 0;
while(i != vec_size(o) || j != vec_size(v)) {
doBak = 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;
doBak = 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!
doBak = 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 + n->namesize);
memcpy(rem->data + rem->filesize, n->filename, n->namesize);
rem->filesize += n->namesize;
fprintf(stderr, "Record new entry: [%s] -> [.backup/.rmlist]\n", n->filename);
}
if (doBak) {
m->namesize += 8;
m->filename = realloc(m->filename, m->namesize);
strcpy(buf, m->filename);
sprintf(m->filename, ".backup/%s", buf);
fprintf(stderr, "[%s] -> [%s]\n", buf, m->filename);
vec_push_back(&bak, m);
// NULL the original entry, so it won't be freed
vec_entry(o)[i - 1] = NULL;
}
}
// Add the backup files to the original ramdisk
vec_for_each(&bak, m) {
vec_push_back(v, m);
}
if (rem->filesize == 0)
rem->remove = 1;
// Cleanup
cpio_vec_destroy(o);
}
static int cpio_restore(struct vector *v) {
cpio_entry *f, *n;
int ret = 1;
vec_for_each(v, f) {
if (strstr(f->filename, ".backup") != NULL) {
ret = 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(0, f->data + pos, v);
}
continue;
} else {
n = xcalloc(sizeof(*n), 1);
memcpy(n, f, sizeof(*f));
n->namesize -= 8;
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);
}
}
}
// Some known stuff we can remove
cpio_rm(0, "sbin/magic_mask.sh", v);
cpio_rm(0, "init.magisk.rc", v);
cpio_rm(0, "magisk", v);
return ret;
}
static void 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 (char *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';
printf("%s\n", sha1);
return;
}
}
} else if (strcmp(f->filename, ".backup/.sha1") == 0) {
printf("%s\n", f->data);
}
}
}
static void cpio_mv(struct vector *v, const char *from, const char *to) {
struct cpio_entry *f, *t;
vec_for_each(v, f) {
if (strcmp(f->filename, from) == 0) {
fprintf(stderr, "Move [%s] -> [%s]\n", from, to);
vec_for_each(v, t) {
if (strcmp(t->filename, to) == 0) {
t->remove = 1;
break;
}
}
free(f->filename);
f->namesize = strlen(to) + 1;
f->filename = strdup(to);
return;
}
}
fprintf(stderr, "Cannot find entry %s\n", from);
exit(1);
}
int cpio_commands(const char *command, int argc, char *argv[]) {
int recursive = 0, ret = 0;
command_t cmd;
char *incpio = argv[0];
++argv;
--argc;
if (strcmp(command, "test") == 0) {
cmd = TEST;
} else if (strcmp(command, "restore") == 0) {
cmd = RESTORE;
} else if (strcmp(command, "stocksha1") == 0) {
cmd = STOCKSHA1;
} else if (argc >= 1 && strcmp(command, "backup") == 0) {
cmd = BACKUP;
} else if (argc > 0 && strcmp(command, "rm") == 0) {
cmd = RM;
if (argc == 2 && strcmp(argv[0], "-r") == 0) {
recursive = 1;
++argv;
--argc;
}
} else if (argc == 2 && strcmp(command, "mv") == 0) {
cmd = MV;
} else if (argc == 2 && strcmp(command, "patch") == 0) {
cmd = PATCH;
} else if (argc == 2 && strcmp(command, "extract") == 0) {
cmd = EXTRACT;
} else if (argc == 2 && strcmp(command, "mkdir") == 0) {
cmd = MKDIR;
} else if (argc == 3 && strcmp(command, "add") == 0) {
cmd = ADD;
} else {
cmd = NONE;
}
struct vector v;
vec_init(&v);
parse_cpio(incpio, &v);
switch(cmd) {
case TEST:
cpio_test(&v);
break;
case RESTORE:
ret = cpio_restore(&v);
break;
case STOCKSHA1:
cpio_stocksha1(&v);
return 0;
case BACKUP:
cpio_backup(argv[0], argc > 1 ? argv[1] : NULL, &v);
case RM:
cpio_rm(recursive, argv[0], &v);
break;
case PATCH:
cpio_patch(&v, strcmp(argv[0], "true") == 0, strcmp(argv[1], "true") == 0);
break;
case EXTRACT:
cpio_extract(argv[0], argv[1], &v);
break;
case MKDIR:
cpio_mkdir(strtoul(argv[0], NULL, 8), argv[1], &v);
break;
case ADD:
cpio_add(strtoul(argv[0], NULL, 8), argv[1], argv[2], &v);
break;
case MV:
cpio_mv(&v, argv[0], argv[1]);
break;
case NONE:
return 1;
}
dump_cpio(incpio, &v);
cpio_vec_destroy(&v);
exit(ret);
}