Magisk/core/jni/magiskboot/ramdisk.c
2017-12-04 15:16:41 +08:00

120 lines
3.3 KiB
C

#include <stdio.h>
#include <unistd.h>
#include <sys/stat.h>
#include "magiskboot.h"
#include "cpio.h"
int check_verity_pattern(const char *s) {
int pos = 0;
if (s[0] == ',') ++pos;
if (strncmp(s + pos, "verify", 6) == 0)
pos += 6;
else if (strncmp(s + pos, "avb", 3) == 0)
pos += 3;
else
return -1;
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;
}
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;
}
}
}
}
int cpio_commands(const char *command, int argc, char *argv[]) {
int ret = 0;
char *incpio = argv[0];
++argv;
--argc;
struct vector v;
vec_init(&v);
parse_cpio(&v, incpio);
if (strcmp(command, "test") == 0) {
return cpio_test(&v);
} else if (strcmp(command, "restore") == 0) {
ret = cpio_restore(&v);
} else if (strcmp(command, "stocksha1") == 0) {
printf("%s\n", cpio_stocksha1(&v));
return 0;
} else if (argc >= 1 && strcmp(command, "backup") == 0) {
cpio_backup(&v, argv[0], argc > 1 ? argv[1] : NULL);
} else if (argc > 0 && strcmp(command, "rm") == 0) {
int recursive = 0;
if (argc == 2 && strcmp(argv[0], "-r") == 0) {
recursive = 1;
++argv;
--argc;
}
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 (argc == 2 && strcmp(command, "extract") == 0) {
return cpio_extract(&v, argv[0], argv[1]);
} 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(ret);
}