Revert "Revert "Adding e4crypt support""

Fix build break caused by original change

This reverts commit 84b0bab58fcc7f225e9a17a15c531b0c2fc509c5.

Change-Id: I99fbd7c3d1ed92db1f546033c8493bb71a327924

9 files changed, 174 insertions, 30 deletions

diff --git a/fs_mgr/fs_mgr.c b/fs_mgr/fs_mgr.c
index d4daed6..273a2ec 100644
--- a/fs_mgr/fs_mgr.c
+++ b/fs_mgr/fs_mgr.c
@@ -31,6 +31,7 @@
 #include <dirent.h>
 #include <ext4.h>
 #include <ext4_sb.h>
+#include <ext4_crypt.h>
 
 #include <linux/loop.h>
 #include <private/android_filesystem_config.h>
@@ -428,6 +429,73 @@ out:
     return ret;
 }
 
+// Check to see if a mountable volume has encryption requirements
+static int handle_encryptable(struct fstab *fstab, const struct fstab_rec* rec)
+{
+    /* If this is block encryptable, need to trigger encryption */
+    if (   (rec->fs_mgr_flags & MF_FORCECRYPT)
+        || (device_is_force_encrypted() && fs_mgr_is_encryptable(rec))) {
+        if (umount(rec->mount_point) == 0) {
+            return FS_MGR_MNTALL_DEV_NEEDS_ENCRYPTION;
+        } else {
+            WARNING("Could not umount %s (%s) - allow continue unencrypted\n",
+                    rec->mount_point, strerror(errno));
+            return FS_MGR_MNTALL_DEV_NOT_ENCRYPTED;
+        }
+    }
+
+    // Deal with file level encryption
+    if (rec->fs_mgr_flags & MF_FILEENCRYPTION) {
+        // Default or not yet initialized encryption requires no more work here
+        if (!e4crypt_non_default_key(rec->mount_point)) {
+            INFO("%s is default file encrypted\n", rec->mount_point);
+            return FS_MGR_MNTALL_DEV_DEFAULT_FILE_ENCRYPTED;
+        }
+
+        INFO("%s is non-default file encrypted\n", rec->mount_point);
+
+        // Uses non-default key, so must unmount and set up temp file system
+        if (umount(rec->mount_point)) {
+            ERROR("Failed to umount %s - rebooting\n", rec->mount_point);
+            return FS_MGR_MNTALL_FAIL;
+        }
+
+        if (fs_mgr_do_tmpfs_mount(rec->mount_point) != 0) {
+            ERROR("Failed to mount a tmpfs at %s\n", rec->mount_point);
+            return FS_MGR_MNTALL_FAIL;
+        }
+
+        // Mount data temporarily so we can access unencrypted dir
+        char tmp_mnt[PATH_MAX];
+        strlcpy(tmp_mnt, rec->mount_point, sizeof(tmp_mnt));
+        strlcat(tmp_mnt, "/tmp_mnt", sizeof(tmp_mnt));
+        if (mkdir(tmp_mnt, 0700)) {
+            ERROR("Failed to create temp mount point\n");
+            return FS_MGR_MNTALL_FAIL;
+        }
+
+        if (fs_mgr_do_mount(fstab, rec->mount_point,
+                            rec->blk_device, tmp_mnt)) {
+            ERROR("Error temp mounting encrypted file system\n");
+            return FS_MGR_MNTALL_FAIL;
+        }
+
+        // Link it to the normal place so ext4_crypt functions work normally
+        strlcat(tmp_mnt, "/unencrypted", sizeof(tmp_mnt));
+        char link_path[PATH_MAX];
+        strlcpy(link_path, rec->mount_point, sizeof(link_path));
+        strlcat(link_path, "/unencrypted", sizeof(link_path));
+        if (symlink(tmp_mnt, link_path)) {
+            ERROR("Error creating symlink to unencrypted directory\n");
+            return FS_MGR_MNTALL_FAIL;
+        }
+
+        return FS_MGR_MNTALL_DEV_NON_DEFAULT_FILE_ENCRYPTED;
+    }
+
+    return FS_MGR_MNTALL_DEV_NOT_ENCRYPTED;
+}
+
 /* When multiple fstab records share the same mount_point, it will
  * try to mount each one in turn, and ignore any duplicates after a
  * first successful mount.
@@ -490,25 +558,21 @@ int fs_mgr_mount_all(struct fstab *fstab)
 
         /* Deal with encryptability. */
         if (!mret) {
-            /* If this is encryptable, need to trigger encryption */
-            if (   (fstab->recs[attempted_idx].fs_mgr_flags & MF_FORCECRYPT)
-                || (device_is_force_encrypted()
-                    && fs_mgr_is_encryptable(&fstab->recs[attempted_idx]))) {
-                if (umount(fstab->recs[attempted_idx].mount_point) == 0) {
-                    if (encryptable == FS_MGR_MNTALL_DEV_NOT_ENCRYPTED) {
-                        ERROR("Will try to encrypt %s %s\n", fstab->recs[attempted_idx].mount_point,
-                              fstab->recs[attempted_idx].fs_type);
-                        encryptable = FS_MGR_MNTALL_DEV_NEEDS_ENCRYPTION;
-                    } else {
-                        ERROR("Only one encryptable/encrypted partition supported\n");
-                        encryptable = FS_MGR_MNTALL_DEV_MIGHT_BE_ENCRYPTED;
-                    }
-                } else {
-                    WARNING("Could not umount %s (%s) - allow continue unencrypted\n",
-                            fstab->recs[attempted_idx].mount_point, strerror(errno));
-                    continue;
+            int status = handle_encryptable(fstab, &fstab->recs[attempted_idx]);
+
+            if (status == FS_MGR_MNTALL_FAIL) {
+                /* Fatal error - no point continuing */
+                return status;
+            }
+
+            if (status != FS_MGR_MNTALL_DEV_NOT_ENCRYPTED) {
+                if (encryptable != FS_MGR_MNTALL_DEV_NOT_ENCRYPTED) {
+                    // Log and continue
+                    ERROR("Only one encryptable/encrypted partition supported\n");
                 }
+                encryptable = status;
             }
+
             /* Success!  Go get the next one */
             continue;
         }
diff --git a/fs_mgr/fs_mgr_fstab.c b/fs_mgr/fs_mgr_fstab.c
index 2c3c90d..8b0f714 100644
--- a/fs_mgr/fs_mgr_fstab.c
+++ b/fs_mgr/fs_mgr_fstab.c
@@ -61,6 +61,7 @@ static struct flag_list fs_mgr_flags[] = {
     { "check",       MF_CHECK },
     { "encryptable=",MF_CRYPT },
     { "forceencrypt=",MF_FORCECRYPT },
+    { "fileencryption",MF_FILEENCRYPTION },
     { "nonremovable",MF_NONREMOVABLE },
     { "voldmanaged=",MF_VOLDMANAGED},
     { "length=",     MF_LENGTH },
@@ -418,27 +419,32 @@ struct fstab_rec *fs_mgr_get_entry_for_mount_point(struct fstab *fstab, const ch
     return fs_mgr_get_entry_for_mount_point_after(NULL, fstab, path);
 }
 
-int fs_mgr_is_voldmanaged(struct fstab_rec *fstab)
+int fs_mgr_is_voldmanaged(const struct fstab_rec *fstab)
 {
     return fstab->fs_mgr_flags & MF_VOLDMANAGED;
 }
 
-int fs_mgr_is_nonremovable(struct fstab_rec *fstab)
+int fs_mgr_is_nonremovable(const struct fstab_rec *fstab)
 {
     return fstab->fs_mgr_flags & MF_NONREMOVABLE;
 }
 
-int fs_mgr_is_verified(struct fstab_rec *fstab)
+int fs_mgr_is_verified(const struct fstab_rec *fstab)
 {
     return fstab->fs_mgr_flags & MF_VERIFY;
 }
 
-int fs_mgr_is_encryptable(struct fstab_rec *fstab)
+int fs_mgr_is_encryptable(const struct fstab_rec *fstab)
 {
     return fstab->fs_mgr_flags & (MF_CRYPT | MF_FORCECRYPT);
 }
 
-int fs_mgr_is_noemulatedsd(struct fstab_rec *fstab)
+int fs_mgr_is_file_encrypted(const struct fstab_rec *fstab)
+{
+    return fstab->fs_mgr_flags & MF_FILEENCRYPTION;
+}
+
+int fs_mgr_is_noemulatedsd(const struct fstab_rec *fstab)
 {
     return fstab->fs_mgr_flags & MF_NOEMULATEDSD;
 }
diff --git a/fs_mgr/fs_mgr_priv.h b/fs_mgr/fs_mgr_priv.h
index 88a1040..d56111a 100644
--- a/fs_mgr/fs_mgr_priv.h
+++ b/fs_mgr/fs_mgr_priv.h
@@ -76,6 +76,7 @@
 #define MF_FORCECRYPT   0x400
 #define MF_NOEMULATEDSD 0x800 /* no emulated sdcard daemon, sd card is the only
                                  external storage */
+#define MF_FILEENCRYPTION 0x2000
 
 #define DM_BUF_SIZE 4096
 
diff --git a/fs_mgr/include/fs_mgr.h b/fs_mgr/include/fs_mgr.h
index ad8a8fc..b5e02f9 100644
--- a/fs_mgr/include/fs_mgr.h
+++ b/fs_mgr/include/fs_mgr.h
@@ -74,10 +74,13 @@ typedef void (*fs_mgr_verity_state_callback)(struct fstab_rec *fstab,
 struct fstab *fs_mgr_read_fstab(const char *fstab_path);
 void fs_mgr_free_fstab(struct fstab *fstab);
 
+#define FS_MGR_MNTALL_DEV_NON_DEFAULT_FILE_ENCRYPTED 5
+#define FS_MGR_MNTALL_DEV_DEFAULT_FILE_ENCRYPTED 4
 #define FS_MGR_MNTALL_DEV_NEEDS_RECOVERY 3
 #define FS_MGR_MNTALL_DEV_NEEDS_ENCRYPTION 2
 #define FS_MGR_MNTALL_DEV_MIGHT_BE_ENCRYPTED 1
 #define FS_MGR_MNTALL_DEV_NOT_ENCRYPTED 0
+#define FS_MGR_MNTALL_FAIL -1
 int fs_mgr_mount_all(struct fstab *fstab);
 
 #define FS_MGR_DOMNT_FAILED -1
@@ -94,11 +97,12 @@ int fs_mgr_add_entry(struct fstab *fstab,
                      const char *mount_point, const char *fs_type,
                      const char *blk_device);
 struct fstab_rec *fs_mgr_get_entry_for_mount_point(struct fstab *fstab, const char *path);
-int fs_mgr_is_voldmanaged(struct fstab_rec *fstab);
-int fs_mgr_is_nonremovable(struct fstab_rec *fstab);
-int fs_mgr_is_verified(struct fstab_rec *fstab);
-int fs_mgr_is_encryptable(struct fstab_rec *fstab);
-int fs_mgr_is_noemulatedsd(struct fstab_rec *fstab);
+int fs_mgr_is_voldmanaged(const struct fstab_rec *fstab);
+int fs_mgr_is_nonremovable(const struct fstab_rec *fstab);
+int fs_mgr_is_verified(const struct fstab_rec *fstab);
+int fs_mgr_is_encryptable(const struct fstab_rec *fstab);
+int fs_mgr_is_file_encrypted(const struct fstab_rec *fstab);
+int fs_mgr_is_noemulatedsd(const struct fstab_rec *fstab);
 int fs_mgr_swapon_all(struct fstab *fstab);
 #ifdef __cplusplus
 }
diff --git a/init/Android.mk b/init/Android.mk
index cb4cb11..dd867cb 100644
--- a/init/Android.mk
+++ b/init/Android.mk
@@ -47,7 +47,7 @@ LOCAL_SRC_FILES:= \
     watchdogd.cpp \
 
 LOCAL_MODULE:= init
-
+LOCAL_C_INCLUDES += system/extras/ext4_utils
 LOCAL_FORCE_STATIC_EXECUTABLE := true
 LOCAL_MODULE_PATH := $(TARGET_ROOT_OUT)
 LOCAL_UNSTRIPPED_PATH := $(TARGET_ROOT_OUT_UNSTRIPPED)
@@ -58,11 +58,14 @@ LOCAL_STATIC_LIBRARIES := \
     liblogwrap \
     libcutils \
     libbase \
+    libext4_utils_static \
+    libutils \
     liblog \
     libc \
     libselinux \
     libmincrypt \
-    libext4_utils_static
+    libc++_static \
+    libdl
 
 # Create symlinks
 LOCAL_POST_INSTALL_CMD := $(hide) mkdir -p $(TARGET_ROOT_OUT)/sbin; \
diff --git a/init/builtins.cpp b/init/builtins.cpp
index 6daea37..9d5b8a8 100644
--- a/init/builtins.cpp
+++ b/init/builtins.cpp
@@ -29,6 +29,7 @@
 #include <sys/wait.h>
 #include <unistd.h>
 #include <linux/loop.h>
+#include <ext4_crypt.h>
 
 #include <selinux/selinux.h>
 #include <selinux/label.h>
@@ -302,7 +303,7 @@ int do_mkdir(int nargs, char **args)
         }
     }
 
-    return 0;
+    return e4crypt_set_directory_policy(args[1]);
 }
 
 static struct {
@@ -446,6 +447,17 @@ static int wipe_data_via_recovery()
     while (1) { pause(); }  // never reached
 }
 
+/*
+ * Callback to make a directory from the ext4 code
+ */
+static int do_mount_alls_make_dir(const char* dir)
+{
+    if (make_dir(dir, 0700) && errno != EEXIST) {
+        return -1;
+    }
+
+    return 0;
+}
 
 /*
  * This function might request a reboot, in which case it will
@@ -514,6 +526,37 @@ int do_mount_all(int nargs, char **args)
         ERROR("fs_mgr_mount_all suggested recovery, so wiping data via recovery.\n");
         ret = wipe_data_via_recovery();
         /* If reboot worked, there is no return. */
+    } else if (ret == FS_MGR_MNTALL_DEV_DEFAULT_FILE_ENCRYPTED) {
+        // We have to create the key files here. Only init can call make_dir,
+        // and we can't do it from fs_mgr as then fs_mgr would depend on
+        // make_dir creating a circular dependency.
+        fstab = fs_mgr_read_fstab(args[1]);
+        for (int i = 0; i < fstab->num_entries; ++i) {
+            if (fs_mgr_is_file_encrypted(&fstab->recs[i])) {
+              if (e4crypt_create_device_key(fstab->recs[i].mount_point,
+                                            do_mount_alls_make_dir)) {
+                    ERROR("Could not create device key on %s"
+                          " - continue unencrypted\n",
+                          fstab->recs[i].mount_point);
+                }
+            }
+        }
+        fs_mgr_free_fstab(fstab);
+
+        if (e4crypt_install_keyring()) {
+            return -1;
+        }
+        property_set("ro.crypto.state", "encrypted");
+
+        // Although encrypted, we have device key, so we do not need to
+        // do anything different from the nonencrypted case.
+        action_for_each_trigger("nonencrypted", action_add_queue_tail);
+    } else if (ret == FS_MGR_MNTALL_DEV_NON_DEFAULT_FILE_ENCRYPTED) {
+        if (e4crypt_install_keyring()) {
+            return -1;
+        }
+        property_set("ro.crypto.state", "encrypted");
+        property_set("vold.decrypt", "trigger_restart_min_framework");
     } else if (ret > 0) {
         ERROR("fs_mgr_mount_all returned unexpected error %d\n", ret);
     }
@@ -866,3 +909,12 @@ int do_wait(int nargs, char **args)
     } else
         return -1;
 }
+
+int do_installkey(int nargs, char **args)
+{
+    if (nargs == 2) {
+        return e4crypt_install_key(args[1]);
+    }
+
+    return -1;
+}
diff --git a/init/init_parser.cpp b/init/init_parser.cpp
index 294dc19..4e18e20 100644
--- a/init/init_parser.cpp
+++ b/init/init_parser.cpp
@@ -153,6 +153,7 @@ static int lookup_keyword(const char *s)
         if (!strcmp(s, "fup")) return K_ifup;
         if (!strcmp(s, "nsmod")) return K_insmod;
         if (!strcmp(s, "mport")) return K_import;
+        if (!strcmp(s, "nstallkey")) return K_installkey;
         break;
     case 'k':
         if (!strcmp(s, "eycodes")) return K_keycodes;
diff --git a/init/keywords.h b/init/keywords.h
index 09f645b..34cb2ad 100644
--- a/init/keywords.h
+++ b/init/keywords.h
@@ -11,6 +11,7 @@ int do_export(int nargs, char **args);
 int do_hostname(int nargs, char **args);
 int do_ifup(int nargs, char **args);
 int do_insmod(int nargs, char **args);
+int do_installkey(int nargs, char **args);
 int do_mkdir(int nargs, char **args);
 int do_mount_all(int nargs, char **args);
 int do_mount(int nargs, char **args);
@@ -61,6 +62,7 @@ enum {
     KEYWORD(hostname,    COMMAND, 1, do_hostname)
     KEYWORD(ifup,        COMMAND, 1, do_ifup)
     KEYWORD(insmod,      COMMAND, 1, do_insmod)
+    KEYWORD(installkey,  COMMAND, 1, do_installkey)
     KEYWORD(import,      SECTION, 1, 0)
     KEYWORD(keycodes,    OPTION,  0, 0)
     KEYWORD(mkdir,       COMMAND, 1, do_mkdir)
diff --git a/rootdir/init.rc b/rootdir/init.rc
index 3ae0954..cda79ce 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -225,6 +225,8 @@ on post-fs
     mkdir /cache/lost+found 0770 root root
 
 on post-fs-data
+    installkey /data
+
     # We chown/chmod /data again so because mount is run as root + defaults
     chown system system /data
     chmod 0771 /data
@@ -303,6 +305,14 @@ on post-fs-data
     # Separate location for storing security policy files on data
     mkdir /data/security 0711 system system
 
+    # Create all remaining /data root dirs so that they are made through init
+    # and get proper encryption policy installed
+    mkdir /data/backup 0700 system system
+    mkdir /data/media 0770 media_rw media_rw
+    mkdir /data/ss 0700 system system
+    mkdir /data/system 0775 system system
+    mkdir /data/user 0711 system system
+
     # Reload policy from /data/security if present.
     setprop selinux.reload_policy 1
 
@@ -438,6 +448,7 @@ on property:vold.decrypt=trigger_restart_min_framework
     class_start main
 
 on property:vold.decrypt=trigger_restart_framework
+    installkey /data
     class_start main
     class_start late_start