Plumbing in PackageManager and installd for multi-user support.

- Create /data/user directory and symlink /data/user/0 -> /data/data for
  backward compatibility
- Create data directories for all packages for new user

- Remove data directories when removing a user

- Create data directories for all users when a package is created

- Clear / Remove data for multiple users

- Fixed a bug in verifying the location of a system app

- pm commands for createUser and removeUser (will be disabled later)

- symlink duplicate lib directories to the original lib directory

Change-Id: Id9fdfcf0e62406a8896aa811314dfc08d5f6ed95

4 files changed, 178 insertions, 14 deletions

diff --git a/cmds/installd/commands.c b/cmds/installd/commands.c
index 80ba1e9..9a93137 100644
--- a/cmds/installd/commands.c
+++ b/cmds/installd/commands.c
@@ -67,15 +67,15 @@ int install(const char *pkgname, uid_t uid, gid_t gid)
     return 0;
 }
 
-int uninstall(const char *pkgname)
+int uninstall(const char *pkgname, uid_t persona)
 {
     char pkgdir[PKG_PATH_MAX];
 
-    if (create_pkg_path(pkgdir, pkgname, PKG_DIR_POSTFIX, 0))
+    if (create_pkg_path(pkgdir, pkgname, PKG_DIR_POSTFIX, persona))
         return -1;
 
-        /* delete contents AND directory, no exceptions */
-    return delete_dir_contents(pkgdir, 1, 0);
+    /* delete contents AND directory, no exceptions */
+    return delete_dir_contents(pkgdir, 1, NULL);
 }
 
 int renamepkg(const char *oldpkgname, const char *newpkgname)
@@ -95,17 +95,48 @@ int renamepkg(const char *oldpkgname, const char *newpkgname)
     return 0;
 }
 
-int delete_user_data(const char *pkgname)
+int delete_user_data(const char *pkgname, uid_t persona)
 {
     char pkgdir[PKG_PATH_MAX];
 
-    if (create_pkg_path(pkgdir, pkgname, PKG_DIR_POSTFIX, 0))
+    if (create_pkg_path(pkgdir, pkgname, PKG_DIR_POSTFIX, persona))
         return -1;
 
-        /* delete contents, excluding "lib", but not the directory itself */
+    /* delete contents, excluding "lib", but not the directory itself */
     return delete_dir_contents(pkgdir, 0, "lib");
 }
 
+int make_user_data(const char *pkgname, uid_t uid, uid_t persona)
+{
+    char pkgdir[PKG_PATH_MAX];
+    char real_libdir[PKG_PATH_MAX];
+
+    // Create the data dir for the package
+    if (create_pkg_path(pkgdir, pkgname, PKG_DIR_POSTFIX, persona)) {
+        return -1;
+    }
+    if (mkdir(pkgdir, 0751) < 0) {
+        LOGE("cannot create dir '%s': %s\n", pkgdir, strerror(errno));
+        return -errno;
+    }
+    if (chown(pkgdir, uid, uid) < 0) {
+        LOGE("cannot chown dir '%s': %s\n", pkgdir, strerror(errno));
+        unlink(pkgdir);
+        return -errno;
+    }
+    return 0;
+}
+
+int delete_persona(uid_t persona)
+{
+    char pkgdir[PKG_PATH_MAX];
+
+    if (create_persona_path(pkgdir, persona))
+        return -1;
+
+    return delete_dir_contents(pkgdir, 1, NULL);
+}
+
 int delete_cache(const char *pkgname)
 {
     char cachedir[PKG_PATH_MAX];
diff --git a/cmds/installd/installd.c b/cmds/installd/installd.c
index e0d0f97..c062d36 100644
--- a/cmds/installd/installd.c
+++ b/cmds/installd/installd.c
@@ -49,7 +49,7 @@ static int do_rm_dex(char **arg, char reply[REPLY_MAX])
 
 static int do_remove(char **arg, char reply[REPLY_MAX])
 {
-    return uninstall(arg[0]); /* pkgname */
+    return uninstall(arg[0], atoi(arg[1])); /* pkgname, userid */
 }
 
 static int do_rename(char **arg, char reply[REPLY_MAX])
@@ -92,7 +92,17 @@ static int do_get_size(char **arg, char reply[REPLY_MAX])
 
 static int do_rm_user_data(char **arg, char reply[REPLY_MAX])
 {
-    return delete_user_data(arg[0]); /* pkgname */
+    return delete_user_data(arg[0], atoi(arg[1])); /* pkgname, userid */
+}
+
+static int do_mk_user_data(char **arg, char reply[REPLY_MAX])
+{
+    return make_user_data(arg[0], atoi(arg[1]), atoi(arg[2])); /* pkgname, uid, userid */
+}
+
+static int do_rm_user(char **arg, char reply[REPLY_MAX])
+{
+    return delete_persona(atoi(arg[0])); /* userid */
 }
 
 static int do_movefiles(char **arg, char reply[REPLY_MAX])
@@ -122,16 +132,18 @@ struct cmdinfo cmds[] = {
     { "dexopt",               3, do_dexopt },
     { "movedex",              2, do_move_dex },
     { "rmdex",                1, do_rm_dex },
-    { "remove",               1, do_remove },
+    { "remove",               2, do_remove },
     { "rename",               2, do_rename },
     { "freecache",            1, do_free_cache },
     { "rmcache",              1, do_rm_cache },
     { "protect",              2, do_protect },
     { "getsize",              3, do_get_size },
-    { "rmuserdata",           1, do_rm_user_data },
+    { "rmuserdata",           2, do_rm_user_data },
     { "movefiles",            0, do_movefiles },
     { "linklib",              2, do_linklib },
     { "unlinklib",            1, do_unlinklib },
+    { "mkuserdata",           3, do_mk_user_data },
+    { "rmuser",               1, do_rm_user },
 };
 
 static int readx(int s, void *_buf, int count)
@@ -286,14 +298,50 @@ int initialize_globals() {
         return -1;
     }
 
+    // append "app/" to dirs[0]
+    char *system_app_path = build_string2(android_system_dirs.dirs[0].path, APP_SUBDIR);
+    android_system_dirs.dirs[0].path = system_app_path;
+    android_system_dirs.dirs[0].len = strlen(system_app_path);
+
     // vendor
     // TODO replace this with an environment variable (doesn't exist yet)
-    android_system_dirs.dirs[1].path = "/vendor/";
+    android_system_dirs.dirs[1].path = "/vendor/app/";
     android_system_dirs.dirs[1].len = strlen(android_system_dirs.dirs[1].path);
 
     return 0;
 }
 
+int initialize_directories() {
+    // /data/user
+    char *user_data_dir = build_string2(android_data_dir.path, SECONDARY_USER_PREFIX);
+    // /data/data
+    char *legacy_data_dir = build_string2(android_data_dir.path, PRIMARY_USER_PREFIX);
+    // /data/user/0
+    char *primary_data_dir = build_string3(android_data_dir.path, SECONDARY_USER_PREFIX,
+            "0");
+    int ret = -1;
+    if (user_data_dir != NULL && primary_data_dir != NULL && legacy_data_dir != NULL) {
+        ret = 0;
+        // Make the /data/user directory if necessary
+        if (access(user_data_dir, R_OK) < 0) {
+            if (mkdir(user_data_dir, 0755) < 0) {
+                return -1;
+            }
+            if (chown(user_data_dir, AID_SYSTEM, AID_SYSTEM) < 0) {
+                return -1;
+            }
+        }
+        // Make the /data/user/0 symlink to /data/data if necessary
+        if (access(primary_data_dir, R_OK) < 0) {
+              ret = symlink(legacy_data_dir, primary_data_dir);
+        }
+        free(user_data_dir);
+        free(legacy_data_dir);
+        free(primary_data_dir);
+    }
+    return ret;
+}
+
 int main(const int argc, const char *argv[]) {
     char buf[BUFFER_MAX];
     struct sockaddr addr;
@@ -305,6 +353,11 @@ int main(const int argc, const char *argv[]) {
         exit(1);
     }
 
+    if (initialize_directories() < 0) {
+        LOGE("Could not create directories; exiting.\n");
+        exit(1);
+    }
+
     lsocket = android_get_control_socket(SOCKET_PATH);
     if (lsocket < 0) {
         LOGE("Failed to get socket from environment: %s\n", strerror(errno));
diff --git a/cmds/installd/installd.h b/cmds/installd/installd.h
index cbca135..e5f6739 100644
--- a/cmds/installd/installd.h
+++ b/cmds/installd/installd.h
@@ -102,6 +102,9 @@ int create_pkg_path(char path[PKG_PATH_MAX],
                     const char *postfix,
                     uid_t persona);
 
+int create_persona_path(char path[PKG_PATH_MAX],
+                    uid_t persona);
+
 int is_valid_package_name(const char* pkgname);
 
 int create_cache_path(char path[PKG_PATH_MAX], const char *src);
@@ -124,12 +127,17 @@ int validate_apk_path(const char *path);
 
 int append_and_increment(char** dst, const char* src, size_t* dst_size);
 
+char *build_string2(char *s1, char *s2);
+char *build_string3(char *s1, char *s2, char *s3);
+
 /* commands.c */
 
 int install(const char *pkgname, uid_t uid, gid_t gid);
-int uninstall(const char *pkgname);
+int uninstall(const char *pkgname, uid_t persona);
 int renamepkg(const char *oldpkgname, const char *newpkgname);
-int delete_user_data(const char *pkgname);
+int delete_user_data(const char *pkgname, uid_t persona);
+int make_user_data(const char *pkgname, uid_t uid, uid_t persona);
+int delete_persona(uid_t persona);
 int delete_cache(const char *pkgname);
 int move_dex(const char *src, const char *dst);
 int rm_dex(const char *path);
diff --git a/cmds/installd/utils.c b/cmds/installd/utils.c
index f37a6fb..3099b83 100644
--- a/cmds/installd/utils.c
+++ b/cmds/installd/utils.c
@@ -96,6 +96,46 @@ int create_pkg_path(char path[PKG_PATH_MAX],
 }
 
 /**
+ * Create the path name for user data for a certain persona.
+ * Returns 0 on success, and -1 on failure.
+ */
+int create_persona_path(char path[PKG_PATH_MAX],
+                    uid_t persona)
+{
+    size_t uid_len;
+    char* persona_prefix;
+    if (persona == 0) {
+        persona_prefix = PRIMARY_USER_PREFIX;
+        uid_len = 0;
+    } else {
+        persona_prefix = SECONDARY_USER_PREFIX;
+        uid_len = snprintf(NULL, 0, "%d", persona);
+    }
+
+    char *dst = path;
+    size_t dst_size = PKG_PATH_MAX;
+
+    if (append_and_increment(&dst, android_data_dir.path, &dst_size) < 0
+            || append_and_increment(&dst, persona_prefix, &dst_size) < 0) {
+        LOGE("Error building prefix for user path");
+        return -1;
+    }
+
+    if (persona != 0) {
+        if (dst_size < uid_len + 1) {
+            LOGE("Error building user path");
+            return -1;
+        }
+        int ret = snprintf(dst, dst_size, "%d", persona);
+        if (ret < 0 || (size_t) ret != uid_len) {
+            LOGE("Error appending persona id to path");
+            return -1;
+        }
+    }
+    return 0;
+}
+
+/**
  * Checks whether the package name is valid. Returns -1 on error and
  * 0 on success.
  */
@@ -408,3 +448,35 @@ int append_and_increment(char** dst, const char* src, size_t* dst_size) {
     *dst_size -= ret;
     return 0;
 }
+
+char *build_string2(char *s1, char *s2) {
+    if (s1 == NULL || s2 == NULL) return NULL;
+
+    int len_s1 = strlen(s1);
+    int len_s2 = strlen(s2);
+    int len = len_s1 + len_s2 + 1;
+    char *result = malloc(len);
+    if (result == NULL) return NULL;
+
+    strcpy(result, s1);
+    strcpy(result + len_s1, s2);
+
+    return result;
+}
+
+char *build_string3(char *s1, char *s2, char *s3) {
+    if (s1 == NULL || s2 == NULL || s3 == NULL) return NULL;
+
+    int len_s1 = strlen(s1);
+    int len_s2 = strlen(s2);
+    int len_s3 = strlen(s3);
+    int len = len_s1 + len_s2 + len_s3 + 1;
+    char *result = malloc(len);
+    if (result == NULL) return NULL;
+
+    strcpy(result, s1);
+    strcpy(result + len_s1, s2);
+    strcpy(result + len_s1 + len_s2, s3);
+
+    return result;
+}