Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit a140afe4 authored by Jeff Sharkey's avatar Jeff Sharkey
Browse files

Add multi-user GIDs to SD card daemon. 

This will eventually allow us to have a single unified filesystem
instead of requiring zygote to use bind mounts.

Change-Id: I1fc4ada4874698a00e7e0b8800617732e69348f0
parent d46335ce

sdcard/sdcard.c

+29 −33
Original line number Diff line number Diff line
@@ -146,8 +146,6 @@ typedef enum { 
    PERM_ANDROID_OBB,

    /* This node is "/Android/media" */

    PERM_ANDROID_MEDIA,

    /* This node is "/Android/user" */

    PERM_ANDROID_USER,

} perm_t;



/* Permissions structure to derive */
@@ -250,7 +248,7 @@ struct fuse { 
    __u32 inode_ctr;



    Hashmap* package_to_appid;

    Hashmap* appid_with_rw;

    Hashmap* uid_with_rw;

};



/* Private data used by a single fuse handler. */
@@ -472,6 +470,7 @@ static void derive_permissions_locked(struct fuse* fuse, struct node *parent, 
        /* Legacy internal layout places users at top level */

        node->perm = PERM_ROOT;

        node->userid = strtoul(node->name, NULL, 10);

        node->gid = multiuser_get_uid(node->userid, AID_SDCARD_R);

        break;

    case PERM_ROOT:

        /* Assume masked off by default. */
@@ -483,14 +482,14 @@ static void derive_permissions_locked(struct fuse* fuse, struct node *parent, 
        } else if (fuse->split_perms) {

            if (!strcasecmp(node->name, "DCIM")

                    || !strcasecmp(node->name, "Pictures")) {

                node->gid = AID_SDCARD_PICS;

                node->gid = multiuser_get_uid(node->userid, AID_SDCARD_PICS);

            } else if (!strcasecmp(node->name, "Alarms")

                    || !strcasecmp(node->name, "Movies")

                    || !strcasecmp(node->name, "Music")

                    || !strcasecmp(node->name, "Notifications")

                    || !strcasecmp(node->name, "Podcasts")

                    || !strcasecmp(node->name, "Ringtones")) {

                node->gid = AID_SDCARD_AV;

                node->gid = multiuser_get_uid(node->userid, AID_SDCARD_AV);

            }

        }

        break;
@@ -510,13 +509,6 @@ static void derive_permissions_locked(struct fuse* fuse, struct node *parent, 
            /* App-specific directories inside; let anyone traverse */

            node->perm = PERM_ANDROID_MEDIA;

            node->mode = 0771;

        } else if (!strcasecmp(node->name, "user")) {

            /* User directories must only be accessible to system, protected

             * by sdcard_all. Zygote will bind mount the appropriate user-

             * specific path. */

            node->perm = PERM_ANDROID_USER;

            node->gid = AID_SDCARD_ALL;

            node->mode = 0770;

        }

        break;

    case PERM_ANDROID_DATA:
@@ -528,13 +520,6 @@ static void derive_permissions_locked(struct fuse* fuse, struct node *parent, 
        }

        node->mode = 0770;

        break;

    case PERM_ANDROID_USER:

        /* Root of a secondary user */

        node->perm = PERM_ROOT;

        node->userid = strtoul(node->name, NULL, 10);

        node->gid = AID_SDCARD_R;

        node->mode = 0771;

        break;

    }

}
@@ -545,8 +530,7 @@ static bool get_caller_has_rw_locked(struct fuse* fuse, const struct fuse_in_hea 
        return true;

    }



    appid_t appid = multiuser_get_app_id(hdr->uid);

    return hashmapContainsKey(fuse->appid_with_rw, (void*) (uintptr_t) appid);

    return hashmapContainsKey(fuse->uid_with_rw, (void*) (uintptr_t) hdr->uid);

}



/* Kernel has already enforced everything we returned through
@@ -725,7 +709,7 @@ static struct node* acquire_or_create_child_locked( 
}



static void fuse_init(struct fuse *fuse, int fd, const char *source_path,

        gid_t write_gid, derive_t derive, bool split_perms) {

        gid_t write_gid, userid_t owner_user, derive_t derive, bool split_perms) {

    pthread_mutex_init(&fuse->lock, NULL);



    fuse->fd = fd;
@@ -760,7 +744,7 @@ static void fuse_init(struct fuse *fuse, int fd, const char *source_path, 
        fuse->root.mode = 0771;

        fuse->root.gid = AID_SDCARD_R;

        fuse->package_to_appid = hashmapCreate(256, str_hash, str_icase_equals);

        fuse->appid_with_rw = hashmapCreate(128, int_hash, int_equals);

        fuse->uid_with_rw = hashmapCreate(128, int_hash, int_equals);

        snprintf(fuse->obbpath, sizeof(fuse->obbpath), "%s/obb", source_path);

        fs_prepare_dir(fuse->obbpath, 0775, getuid(), getgid());

        break;
@@ -769,9 +753,10 @@ static void fuse_init(struct fuse *fuse, int fd, const char *source_path, 
         * /Android/user and shared OBB path under /Android/obb. */

        fuse->root.perm = PERM_ROOT;

        fuse->root.mode = 0771;

        fuse->root.gid = AID_SDCARD_R;

        fuse->root.userid = owner_user;

        fuse->root.gid = multiuser_get_uid(owner_userid, AID_SDCARD_R);

        fuse->package_to_appid = hashmapCreate(256, str_hash, str_icase_equals);

        fuse->appid_with_rw = hashmapCreate(128, int_hash, int_equals);

        fuse->uid_with_rw = hashmapCreate(128, int_hash, int_equals);

        snprintf(fuse->obbpath, sizeof(fuse->obbpath), "%s/Android/obb", source_path);

        break;

    }
@@ -1692,7 +1677,7 @@ static int read_package_list(struct fuse *fuse) { 
    pthread_mutex_lock(&fuse->lock);



    hashmapForEach(fuse->package_to_appid, remove_str_to_int, fuse->package_to_appid);

    hashmapForEach(fuse->appid_with_rw, remove_int_to_null, fuse->appid_with_rw);

    hashmapForEach(fuse->uid_with_rw, remove_int_to_null, fuse->uid_with_rw);



    FILE* file = fopen(kPackagesListFile, "r");

    if (!file) {
@@ -1713,8 +1698,14 @@ static int read_package_list(struct fuse *fuse) { 


            char* token = strtok(gids, ",");

            while (token != NULL) {

                if (strtoul(token, NULL, 10) == fuse->write_gid) {

                    hashmapPut(fuse->appid_with_rw, (void*) (uintptr_t) appid, (void*) (uintptr_t) 1);

                // Current packages.list format is a bit funky; it blends per

                // user GID membership into a single per-app line. Here we

                // work backwards from the groups to build the per-user UIDs

                // that have write permission.

                gid_t gid = strtoul(token, NULL, 10);

                if (multiuser_get_app_id(gid) == fuse->write_gid) {

                    uid_t uid = multiuser_get_uid(multiuser_get_user_id(gid), appid);

                    hashmapPut(fuse->uid_with_rw, (void*) (uintptr_t) uid, (void*) (uintptr_t) 1);

                    break;

                }

                token = strtok(NULL, ",");
@@ -1724,7 +1715,7 @@ static int read_package_list(struct fuse *fuse) { 


    TRACE("read_package_list: found %zu packages, %zu with write_gid\n",

            hashmapSize(fuse->package_to_appid),

            hashmapSize(fuse->appid_with_rw));

            hashmapSize(fuse->uid_with_rw));

    fclose(file);

    pthread_mutex_unlock(&fuse->lock);

    return 0;
@@ -1849,7 +1840,7 @@ static int usage() 
}



static int run(const char* source_path, const char* dest_path, uid_t uid,

        gid_t gid, gid_t write_gid, int num_threads, derive_t derive,

        gid_t gid, gid_t write_gid, userid_t owner_user, int num_threads, derive_t derive,

        bool split_perms) {

    int fd;

    char opts[256];
@@ -1893,7 +1884,7 @@ static int run(const char* source_path, const char* dest_path, uid_t uid, 
        goto error;

    }



    fuse_init(&fuse, fd, source_path, write_gid, derive, split_perms);

    fuse_init(&fuse, fd, source_path, write_gid, owner_user, derive, split_perms);



    umask(0);

    res = ignite_fuse(&fuse, num_threads);
@@ -1914,6 +1905,7 @@ int main(int argc, char **argv) 
    uid_t uid = 0;

    gid_t gid = 0;

    gid_t write_gid = AID_SDCARD_RW;

    userid_t owner_user = 0;

    int num_threads = DEFAULT_NUM_THREADS;

    derive_t derive = DERIVE_NONE;

    bool split_perms = false;
@@ -1922,7 +1914,7 @@ int main(int argc, char **argv) 
    int fs_version;



    int opt;

    while ((opt = getopt(argc, argv, "u:g:w:t:dls")) != -1) {

    while ((opt = getopt(argc, argv, "u:g:w:o:t:dls")) != -1) {

        switch (opt) {

            case 'u':

                uid = strtoul(optarg, NULL, 10);
@@ -1933,6 +1925,9 @@ int main(int argc, char **argv) 
            case 'w':

                write_gid = strtoul(optarg, NULL, 10);

                break;

            case 'o':

                owner_user = strtoul(optarg, NULL, 10);

                break;

            case 't':

                num_threads = strtoul(optarg, NULL, 10);

                break;
@@ -1999,6 +1994,7 @@ int main(int argc, char **argv) 
        sleep(1);

    }



    res = run(source_path, dest_path, uid, gid, write_gid, num_threads, derive, split_perms);

    res = run(source_path, dest_path, uid, gid, write_gid, owner_user,

            num_threads, derive, split_perms);

    return res < 0 ? 1 : 0;

}