Revert "Add fileencrypted=software/ice to fstab options"
This reverts commit e8299d81a18d16b006019f37ec9d84921d5ff845.
Bug: 28905864
Change-Id: I077f1ce7337c7ff42be67fb7acbb80ce5ee9b9ba
diff --git a/ext4_utils/Android.mk b/ext4_utils/Android.mk
index e5431dd..a8362b2 100644
--- a/ext4_utils/Android.mk
+++ b/ext4_utils/Android.mk
@@ -87,7 +87,6 @@
LOCAL_SRC_FILES := $(libext4_utils_src_files) \
ext4_crypt_init_extensions.cpp
LOCAL_MODULE := libext4_utils_static
-LOCAL_C_INCLUDES += system/core/init
# Various instances of dereferencing a type-punned pointer in extent.c
LOCAL_CFLAGS += -fno-strict-aliasing
LOCAL_STATIC_LIBRARIES := \
diff --git a/ext4_utils/ext4_crypt.cpp b/ext4_utils/ext4_crypt.cpp
index 72ce104..be77b79 100644
--- a/ext4_utils/ext4_crypt.cpp
+++ b/ext4_utils/ext4_crypt.cpp
@@ -16,11 +16,182 @@
#include "ext4_crypt.h"
+#include <dirent.h>
+#include <errno.h>
#include <string.h>
+#include <unistd.h>
+
+#include <fcntl.h>
+#include <asm/ioctl.h>
+#include <sys/syscall.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <android-base/logging.h>
#include <cutils/properties.h>
+#define XATTR_NAME_ENCRYPTION_POLICY "encryption.policy"
+#define EXT4_KEYREF_DELIMITER ((char)'.')
+
+// ext4enc:TODO Include structure from somewhere sensible
+// MUST be in sync with ext4_crypto.c in kernel
+#define EXT4_KEY_DESCRIPTOR_SIZE 8
+#define EXT4_KEY_DESCRIPTOR_SIZE_HEX 17
+
+struct ext4_encryption_policy {
+ char version;
+ char contents_encryption_mode;
+ char filenames_encryption_mode;
+ char flags;
+ char master_key_descriptor[EXT4_KEY_DESCRIPTOR_SIZE];
+} __attribute__((__packed__));
+
+#define EXT4_ENCRYPTION_MODE_AES_256_XTS 1
+#define EXT4_ENCRYPTION_MODE_AES_256_CTS 4
+
+// ext4enc:TODO Get value from somewhere sensible
+#define EXT4_IOC_SET_ENCRYPTION_POLICY _IOR('f', 19, struct ext4_encryption_policy)
+#define EXT4_IOC_GET_ENCRYPTION_POLICY _IOW('f', 21, struct ext4_encryption_policy)
+
+#define HEX_LOOKUP "0123456789abcdef"
+
bool e4crypt_is_native() {
char value[PROPERTY_VALUE_MAX];
property_get("ro.crypto.type", value, "none");
return !strcmp(value, "file");
}
+
+static void policy_to_hex(const char* policy, char* hex) {
+ for (size_t i = 0, j = 0; i < EXT4_KEY_DESCRIPTOR_SIZE; i++) {
+ hex[j++] = HEX_LOOKUP[(policy[i] & 0xF0) >> 4];
+ hex[j++] = HEX_LOOKUP[policy[i] & 0x0F];
+ }
+ hex[EXT4_KEY_DESCRIPTOR_SIZE_HEX - 1] = '\0';
+}
+
+static bool is_dir_empty(const char *dirname, bool *is_empty)
+{
+ int n = 0;
+ auto dirp = std::unique_ptr<DIR, int (*)(DIR*)>(opendir(dirname), closedir);
+ if (!dirp) {
+ PLOG(ERROR) << "Unable to read directory: " << dirname;
+ return false;
+ }
+ for (;;) {
+ errno = 0;
+ auto entry = readdir(dirp.get());
+ if (!entry) {
+ if (errno) {
+ PLOG(ERROR) << "Unable to read directory: " << dirname;
+ return false;
+ }
+ break;
+ }
+ if (strcmp(entry->d_name, "lost+found") != 0) { // Skip lost+found
+ ++n;
+ if (n > 2) {
+ *is_empty = false;
+ return true;
+ }
+ }
+ }
+ *is_empty = true;
+ return true;
+}
+
+static bool e4crypt_policy_set(const char *directory, const char *policy, size_t policy_length) {
+ if (policy_length != EXT4_KEY_DESCRIPTOR_SIZE) {
+ LOG(ERROR) << "Policy wrong length: " << policy_length;
+ return false;
+ }
+ int fd = open(directory, O_DIRECTORY | O_NOFOLLOW | O_CLOEXEC);
+ if (fd == -1) {
+ PLOG(ERROR) << "Failed to open directory " << directory;
+ return false;
+ }
+
+ ext4_encryption_policy eep;
+ eep.version = 0;
+ eep.contents_encryption_mode = EXT4_ENCRYPTION_MODE_AES_256_XTS;
+ eep.filenames_encryption_mode = EXT4_ENCRYPTION_MODE_AES_256_CTS;
+ eep.flags = 0;
+ memcpy(eep.master_key_descriptor, policy, EXT4_KEY_DESCRIPTOR_SIZE);
+ if (ioctl(fd, EXT4_IOC_SET_ENCRYPTION_POLICY, &eep)) {
+ PLOG(ERROR) << "Failed to set encryption policy for " << directory;
+ close(fd);
+ return false;
+ }
+ close(fd);
+
+ char policy_hex[EXT4_KEY_DESCRIPTOR_SIZE_HEX];
+ policy_to_hex(policy, policy_hex);
+ LOG(INFO) << "Policy for " << directory << " set to " << policy_hex;
+ return true;
+}
+
+static bool e4crypt_policy_get(const char *directory, char *policy, size_t policy_length) {
+ if (policy_length != EXT4_KEY_DESCRIPTOR_SIZE) {
+ LOG(ERROR) << "Policy wrong length: " << policy_length;
+ return false;
+ }
+
+ int fd = open(directory, O_DIRECTORY | O_NOFOLLOW | O_CLOEXEC);
+ if (fd == -1) {
+ PLOG(ERROR) << "Failed to open directory " << directory;
+ return false;
+ }
+
+ ext4_encryption_policy eep;
+ memset(&eep, 0, sizeof(ext4_encryption_policy));
+ if (ioctl(fd, EXT4_IOC_GET_ENCRYPTION_POLICY, &eep) != 0) {
+ PLOG(ERROR) << "Failed to get encryption policy for " << directory;
+ close(fd);
+ return -1;
+ }
+ close(fd);
+
+ if ((eep.version != 0)
+ || (eep.contents_encryption_mode != EXT4_ENCRYPTION_MODE_AES_256_XTS)
+ || (eep.filenames_encryption_mode != EXT4_ENCRYPTION_MODE_AES_256_CTS)
+ || (eep.flags != 0)) {
+ LOG(ERROR) << "Failed to find matching encryption policy for " << directory;
+ return false;
+ }
+ memcpy(policy, eep.master_key_descriptor, EXT4_KEY_DESCRIPTOR_SIZE);
+
+ return true;
+}
+
+static bool e4crypt_policy_check(const char *directory, const char *policy, size_t policy_length) {
+ if (policy_length != EXT4_KEY_DESCRIPTOR_SIZE) {
+ LOG(ERROR) << "Policy wrong length: " << policy_length;
+ return false;
+ }
+ char existing_policy[EXT4_KEY_DESCRIPTOR_SIZE];
+ if (!e4crypt_policy_get(directory, existing_policy, EXT4_KEY_DESCRIPTOR_SIZE)) return false;
+ char existing_policy_hex[EXT4_KEY_DESCRIPTOR_SIZE_HEX];
+
+ policy_to_hex(existing_policy, existing_policy_hex);
+
+ if (memcmp(policy, existing_policy, EXT4_KEY_DESCRIPTOR_SIZE) != 0) {
+ char policy_hex[EXT4_KEY_DESCRIPTOR_SIZE_HEX];
+ policy_to_hex(policy, policy_hex);
+ LOG(ERROR) << "Found policy " << existing_policy_hex << " at " << directory
+ << " which doesn't match expected value " << policy_hex;
+ return false;
+ }
+ LOG(INFO) << "Found policy " << existing_policy_hex << " at " << directory
+ << " which matches expected value";
+ return true;
+}
+
+int e4crypt_policy_ensure(const char *directory, const char *policy, size_t policy_length) {
+ bool is_empty;
+ if (!is_dir_empty(directory, &is_empty)) return -1;
+ if (is_empty) {
+ if (!e4crypt_policy_set(directory, policy, policy_length)) return -1;
+ } else {
+ if (!e4crypt_policy_check(directory, policy, policy_length)) return -1;
+ }
+ return 0;
+}
diff --git a/ext4_utils/ext4_crypt.h b/ext4_utils/ext4_crypt.h
index 8a83da1..ddc09a7 100644
--- a/ext4_utils/ext4_crypt.h
+++ b/ext4_utils/ext4_crypt.h
@@ -20,9 +20,11 @@
__BEGIN_DECLS
+bool e4crypt_is_native();
+
+int e4crypt_policy_ensure(const char *directory, const char* policy, size_t policy_length);
+
static const char* e4crypt_unencrypted_folder = "/unencrypted";
static const char* e4crypt_key_ref = "/unencrypted/ref";
-bool e4crypt_is_native();
-
__END_DECLS
diff --git a/ext4_utils/ext4_crypt_init_extensions.cpp b/ext4_utils/ext4_crypt_init_extensions.cpp
index 0298b11..c6baea7 100644
--- a/ext4_utils/ext4_crypt_init_extensions.cpp
+++ b/ext4_utils/ext4_crypt_init_extensions.cpp
@@ -24,11 +24,18 @@
#include <string>
#include <vector>
+#include <dirent.h>
+#include <errno.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
#include <android-base/file.h>
#include <cutils/klog.h>
+#include <cutils/properties.h>
+#include <cutils/sockets.h>
#include <logwrap/logwrap.h>
-#include <util.h>
#include "key_control.h"
@@ -110,6 +117,9 @@
return 0;
}
+ // Special case various directories that must not be encrypted,
+ // often because their subdirectories must be encrypted.
+ // This isn't a nice way to do this, see b/26641735
std::vector<std::string> directories_to_exclude = {
"lost+found",
"system_ce", "system_de",
@@ -131,19 +141,12 @@
KLOG_ERROR(TAG, "Unable to read system policy to set on %s\n", dir);
return -1;
}
-
- std::string hex_policy = bytes_to_hex((const uint8_t*)policy.c_str(),
- policy.length());
-
- const char* argv[] = { "/system/bin/vdc", "--wait", "cryptfs",
- "ensure_policy", dir, hex_policy.c_str()};
-
KLOG_INFO(TAG, "Setting policy on %s\n", dir);
- int rc = android_fork_execvp(6, (char**) argv, NULL, false, true);
- if (rc) {
- KLOG_ERROR(TAG, "Setting %s policy on %s failed!\n",
- hex_policy.c_str(), dir);
- return rc;
+ int result = e4crypt_policy_ensure(dir, policy.c_str(), policy.size());
+ if (result) {
+ KLOG_ERROR(TAG, "Setting %02x%02x%02x%02x policy on %s failed!\n",
+ policy[0], policy[1], policy[2], policy[3], dir);
+ return -1;
}
return 0;
