Add getfooter tool for crypto debugging
Change-Id: I3b9e5f72f3c1c77e41a45d3c94a44f36cc5cbc3c
diff --git a/Android.mk b/Android.mk
index 98ea68d9..d96e53f 100644
--- a/Android.mk
+++ b/Android.mk
@@ -356,6 +356,7 @@
include $(commands_recovery_local_path)/crypto/fs_mgr/Android.mk
include $(commands_recovery_local_path)/crypto/logwrapper/Android.mk
include $(commands_recovery_local_path)/crypto/scrypt/Android.mk
+ include $(commands_recovery_local_path)/crypto/crypttools/Android.mk
endif
ifeq ($(HAVE_SELINUX), true)
include $(commands_recovery_local_path)/minzip/Android.mk
diff --git a/crypto/crypttools/Android.mk b/crypto/crypttools/Android.mk
new file mode 100644
index 0000000..a2f8dfe
--- /dev/null
+++ b/crypto/crypttools/Android.mk
@@ -0,0 +1,15 @@
+LOCAL_PATH:= $(call my-dir)
+include $(CLEAR_VARS)
+ifeq ($(TW_INCLUDE_JB_CRYPTO), true)
+LOCAL_SRC_FILES:= \
+ getfooter.c
+LOCAL_CFLAGS:= -g -c -W
+LOCAL_MODULE:=getfooter
+LOCAL_MODULE_TAGS:= eng
+LOCAL_STATIC_LIBRARIES += libfs_mgrtwrp libc libcutils
+LOCAL_MODULE_CLASS := UTILITY_EXECUTABLES
+LOCAL_MODULE_PATH := $(PRODUCT_OUT)/utilities
+LOCAL_FORCE_STATIC_EXECUTABLE := true
+LOCAL_C_INCLUDES := bootable/recovery/crypto/jb/
+include $(BUILD_EXECUTABLE)
+endif
\ No newline at end of file
diff --git a/crypto/crypttools/getfooter.c b/crypto/crypttools/getfooter.c
new file mode 100644
index 0000000..aa7f88e
--- /dev/null
+++ b/crypto/crypttools/getfooter.c
@@ -0,0 +1,219 @@
+#include <sys/types.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <linux/dm-ioctl.h>
+#include <sys/mount.h>
+#include "../fs_mgr/include/fs_mgr.h"
+#include "cryptfs.h"
+
+#include "cutils/properties.h"
+
+#ifndef PROPERTY_VALUE_MAX
+#define PROPERTY_VALUE_MAX 255
+#endif
+#ifndef FSTAB_PREFIX
+#define FSTAB_PREFIX "/fstab."
+#endif
+#ifndef KEY_IN_FOOTER
+#define KEY_IN_FOOTER "footer"
+#endif
+
+struct fstab *fstab;
+
+static unsigned int get_blkdev_size(int fd)
+{
+ unsigned int nr_sec;
+
+ if ( (ioctl(fd, BLKGETSIZE, &nr_sec)) == -1) {
+ nr_sec = 0;
+ }
+
+ return nr_sec;
+}
+
+int get_crypt_ftr_info(char **metadata_fname, off64_t *off)
+{
+ static int cached_data = 0;
+ static off64_t cached_off = 0;
+ static char cached_metadata_fname[PROPERTY_VALUE_MAX] = "";
+ int fd;
+ char key_loc[PROPERTY_VALUE_MAX];
+ char real_blkdev[PROPERTY_VALUE_MAX];
+ unsigned int nr_sec;
+ int rc = -1;
+
+ fs_mgr_get_crypt_info(fstab, key_loc, real_blkdev, sizeof(key_loc));
+
+ if (!strcmp(key_loc, KEY_IN_FOOTER)) {
+ if ( (fd = open(real_blkdev, O_RDWR)) < 0) {
+ printf("Cannot open real block device %s\n", real_blkdev);
+ return -1;
+ }
+
+ if ((nr_sec = get_blkdev_size(fd))) {
+ /* If it's an encrypted Android partition, the last 16 Kbytes contain the
+ * encryption info footer and key, and plenty of bytes to spare for future
+ * growth.
+ */
+ strlcpy(cached_metadata_fname, real_blkdev, sizeof(cached_metadata_fname));
+ cached_off = ((off64_t)nr_sec * 512) - CRYPT_FOOTER_OFFSET;
+ cached_data = 1;
+ } else {
+ printf("Cannot get size of block device %s\n", real_blkdev);
+ }
+ close(fd);
+ } else {
+ strlcpy(cached_metadata_fname, key_loc, sizeof(cached_metadata_fname));
+ cached_off = 0;
+ cached_data = 1;
+ }
+
+ if (cached_data) {
+ if (metadata_fname) {
+ *metadata_fname = cached_metadata_fname;
+ }
+ if (off) {
+ *off = cached_off;
+ }
+ rc = 0;
+ }
+
+ return rc;
+}
+
+int get_crypt_ftr_and_key(struct crypt_mnt_ftr *crypt_ftr)
+{
+ int fd;
+ unsigned int nr_sec, cnt;
+ off64_t starting_off;
+ int rc = -1;
+ char *fname = NULL;
+ struct stat statbuf;
+
+ if (get_crypt_ftr_info(&fname, &starting_off)) {
+ printf("Unable to get crypt_ftr_info\n");
+ return -1;
+ }
+ if (fname[0] != '/') {
+ printf("Unexpected value for crypto key location '%s'\n", fname);
+ //return -1;
+ }
+ if ( (fd = open(fname, O_RDWR)) < 0) {
+ printf("Cannot open footer file %s for get\n", fname);
+ return -1;
+ }
+
+ /* Make sure it's 16 Kbytes in length */
+ fstat(fd, &statbuf);
+ if (S_ISREG(statbuf.st_mode) && (statbuf.st_size != 0x4000)) {
+ printf("footer file %s is not the expected size!\n", fname);
+ close(fd);
+ return -1;
+ }
+
+ /* Seek to the start of the crypt footer */
+ if (lseek64(fd, starting_off, SEEK_SET) == -1) {
+ printf("Cannot seek to real block device footer\n");
+ close(fd);
+ return -1;
+ }
+
+ if ( (cnt = read(fd, crypt_ftr, sizeof(struct crypt_mnt_ftr))) != sizeof(struct crypt_mnt_ftr)) {
+ printf("Cannot read real block device footer\n");
+ close(fd);
+ return -1;
+ }
+ close(fd);
+ return 0;
+}
+
+int main(void)
+{
+ char key_loc[PROPERTY_VALUE_MAX];
+ char blk_dev[PROPERTY_VALUE_MAX];
+ char fstab_filename[PROPERTY_VALUE_MAX + sizeof(FSTAB_PREFIX)];
+ struct stat st;
+ struct crypt_mnt_ftr crypt_ftr;
+ int fdout;
+
+ printf("This tool comes with no warranties whatsoever.\n");
+ printf("http://teamw.in\n\n");
+ strcpy(fstab_filename, FSTAB_PREFIX);
+ property_get("ro.hardware", fstab_filename + sizeof(FSTAB_PREFIX) - 1, "");
+
+ if (stat(fstab_filename, &st) != 0) {
+ printf("Cannot locate fstab file '%s'\n", fstab_filename);
+ return -1;
+ }
+
+ fstab = fs_mgr_read_fstab(fstab_filename);
+ if (!fstab) {
+ printf("failed to open %s\n", fstab_filename);
+ return -1;
+ }
+
+ fs_mgr_get_crypt_info(fstab, key_loc, blk_dev, sizeof(blk_dev));
+
+ if (get_crypt_ftr_and_key(&crypt_ftr)) {
+ printf("Error getting crypt footer and key\n");
+ return -1;
+ }
+
+ if ( (fdout = open("/footerfile", O_WRONLY | O_CREAT, 0644)) < 0) {
+ printf("Cannot open output file /footerfile\n");
+ return -1;
+ }
+ if (write(fdout, (void*) &crypt_ftr, sizeof(struct crypt_mnt_ftr)) != sizeof(struct crypt_mnt_ftr)) {
+ printf("Failed to write footer.\n");
+ }
+ close(fdout);
+
+ if (!strcmp(key_loc, KEY_IN_FOOTER)) {
+ unsigned int nr_sec, cnt;
+ off64_t off = 0;
+ char buffer[CRYPT_FOOTER_OFFSET];
+ int fd;
+
+ printf("\n\nDumping footer from '%s'...\n", blk_dev);
+ if ( (fd = open(blk_dev, O_RDONLY)) < 0) {
+ printf("Cannot open real block device %s\n", blk_dev);
+ return -1;
+ }
+
+ if ((nr_sec = get_blkdev_size(fd))) {
+ off = ((off64_t)nr_sec * 512) - CRYPT_FOOTER_OFFSET;
+ } else {
+ printf("Cannot get size of block device %s\n", blk_dev);
+ close(fd);
+ return -1;
+ }
+ printf("Size is %llu, offset is %llu\n", ((off64_t)nr_sec * 512), off);
+ if (lseek64(fd, off, SEEK_SET) == -1) {
+ printf("Cannot seek to real block device footer\n");
+ close(fd);
+ return -1;
+ }
+
+ if ( (cnt = read(fd, buffer, sizeof(buffer))) != sizeof(buffer)) {
+ printf("Cannot read real block device footer\n");
+ close(fd);
+ return -1;
+ }
+ close(fd);
+ if ( (fdout = open("/footerdump", O_WRONLY | O_CREAT, 0644)) < 0) {
+ printf("Cannot open output file /footerdump\n");
+ return -1;
+ }
+ if (write(fdout, buffer, sizeof(buffer)) != sizeof(buffer)) {
+ printf("Failed to write footer.\n");
+ }
+ close(fdout);
+ }
+
+ return 0;
+}