cmd/rmvolmgr/rmvolmgr.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * rmvolmgr daemon
 */

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <dirent.h>
#include <signal.h>
#include <unistd.h>
#include <fcntl.h>
#include <strings.h>
#include <errno.h>
#include <libintl.h>
#include <sys/syscall.h>
#include <libscf.h>
#include <priv_utils.h>

#include <dbus/dbus.h>
#include <dbus/dbus-glib.h>
#include <dbus/dbus-glib-lowlevel.h>
#include <libhal.h>

#include "rmm_common.h"

char *progname = "rmvolmgr";

#define RMVOLMGR_FMRI   "svc:/system/filesystem/rmvolmgr:default"

typedef struct managed_volume {
    char            *udi;
    boolean_t       my;
    struct action_arg   aa;
} managed_volume_t;

static GSList       *managed_volumes;

static GMainLoop    *mainloop;
static LibHalContext    *hal_ctx;
static int      sigexit_pipe[2];
static GIOChannel   *sigexit_ioch;

static boolean_t    opt_c;  /* disable CDE compatibility */
static boolean_t    opt_n;  /* disable legacy mountpoint symlinks */
static boolean_t    opt_s;  /* system instance */

/* SMF property "eject_button" */
static boolean_t    rmm_prop_eject_button = B_TRUE;

static void get_smf_properties();
static void rmm_device_added(LibHalContext *ctx, const char *udi);
static void rmm_device_removed(LibHalContext *ctx, const char *udi);
static void rmm_property_modified(LibHalContext *ctx, const char *udi,
        const char *key, dbus_bool_t is_removed, dbus_bool_t is_added);
static void rmm_device_condition(LibHalContext *ctx, const char *udi,
        const char *name, const char *detail);
static void rmm_mount_all();
static void rmm_unmount_all();
static void sigexit(int signo);
static gboolean sigexit_ioch_func(GIOChannel *source, GIOCondition condition,
        gpointer user_data);

static void
usage()
{
    (void) fprintf(stderr, gettext("\nusage: rmvolmgr [-v]\n"));
}

static int
rmvolmgr(int argc, char **argv)
{
    const char  *opts = "chnsv";
    DBusError   error;
    boolean_t   daemonize;
    rmm_error_t rmm_error;
    int     c;

    while ((c = getopt(argc, argv, opts)) != EOF) {
        switch (c) {
        case 'c':
            opt_c = B_TRUE;
            break;
        case 'n':
            opt_n = B_TRUE;
            break;
        case 's':
            opt_s = B_TRUE;
            break;
        case 'v':
            rmm_debug = 1;
            break;
        case '?':
        case 'h':
            usage();
            return (0);
        default:
            usage();
            return (1);
        }
    }

    if (opt_s) {
        if (geteuid() != 0) {
            (void) fprintf(stderr,
                gettext("system instance must have euid 0\n"));
            return (1);
        }

        get_smf_properties();

        if (opt_c) {
            rmm_vold_actions_enabled = B_FALSE;
        }
        if (opt_n) {
            rmm_vold_mountpoints_enabled = B_FALSE;
        }


        /*
         * Drop unused privileges. Remain root for HAL interaction
         * and to create legacy symlinks.
         *
         * Need PRIV_FILE_DAC_WRITE to write to users'
         * /tmp/.removable/notify* files.
         */
        if (__init_daemon_priv(PU_RESETGROUPS|PU_CLEARLIMITSET,
            0, 0,
            rmm_vold_actions_enabled ? PRIV_FILE_DAC_WRITE : NULL,
            NULL) == -1) {
            (void) fprintf(stderr,
                gettext("failed to drop privileges"));
            return (1);
        }
        /* basic privileges we don't need */
        (void) priv_set(PRIV_OFF, PRIV_PERMITTED, PRIV_PROC_EXEC,
            PRIV_PROC_INFO, PRIV_FILE_LINK_ANY, PRIV_PROC_SESSION,
            NULL);

    } else {
        if (opt_c) {
            rmm_vold_actions_enabled = B_FALSE;
        }
        if (opt_n) {
            rmm_vold_mountpoints_enabled = B_FALSE;
        }
    }

    daemonize = (getenv("RMVOLMGR_NODAEMON") == NULL);

    if (daemonize && daemon(0, 0) < 0) {
        dprintf("daemonizing failed: %s", strerror(errno));
        return (1);
    }

    if (opt_s) {
        __fini_daemon_priv(PRIV_PROC_FORK, NULL);
    }

    /*
     * signal mainloop integration using pipes
     */
    if (pipe(sigexit_pipe) != 0) {
        dprintf("pipe failed %s\n", strerror(errno));
        return (1);
    }
    sigexit_ioch = g_io_channel_unix_new(sigexit_pipe[0]);
    if (sigexit_ioch == NULL) {
        dprintf("g_io_channel_unix_new failed\n");
        return (1);
    }
    g_io_add_watch(sigexit_ioch, G_IO_IN, sigexit_ioch_func, NULL);
    signal(SIGTERM, sigexit);
    signal(SIGINT, sigexit);
    signal(SIGHUP, SIG_IGN);
    signal(SIGUSR1, SIG_IGN);
    signal(SIGUSR2, SIG_IGN);

    if ((hal_ctx = rmm_hal_init(rmm_device_added, rmm_device_removed,
        rmm_property_modified, rmm_device_condition,
        &error, &rmm_error)) == NULL) {
        dbus_error_free(&error);
        return (1);
    }

    /* user instance should claim devices */
    if (!opt_s) {
        if (!rmm_hal_claim_branch(hal_ctx, HAL_BRANCH_LOCAL)) {
            (void) fprintf(stderr,
                gettext("cannot claim branch\n"));
            return (1);
        }
    }

    rmm_mount_all();

    if ((mainloop = g_main_loop_new(NULL, B_FALSE)) == NULL) {
        dprintf("Cannot create main loop\n");
        return (1);
    }

    g_main_loop_run(mainloop);

    return (0);
}

static void
get_smf_properties()
{
    scf_simple_prop_t *prop;
    uint8_t *val;

    if ((prop = scf_simple_prop_get(NULL, RMVOLMGR_FMRI,
        "rmvolmgr", "legacy_mountpoints")) != NULL) {
        if ((val = scf_simple_prop_next_boolean(prop)) != NULL) {
            rmm_vold_mountpoints_enabled = (*val != 0);
        }
        scf_simple_prop_free(prop);
    }

    if ((prop = scf_simple_prop_get(NULL, RMVOLMGR_FMRI,
        "rmvolmgr", "cde_compatible")) != NULL) {
        if ((val = scf_simple_prop_next_boolean(prop)) != NULL) {
            rmm_vold_actions_enabled = (*val != 0);
        }
        scf_simple_prop_free(prop);
    }

    if ((prop = scf_simple_prop_get(NULL, RMVOLMGR_FMRI,
        "rmvolmgr", "eject_button")) != NULL) {
        if ((val = scf_simple_prop_next_boolean(prop)) != NULL) {
            rmm_prop_eject_button = (*val != 0);
        }
        scf_simple_prop_free(prop);
    }
}

/* ARGSUSED */
static void
sigexit(int signo)
{
    dprintf("signal to exit %d\n", signo);

    write(sigexit_pipe[1], "s", 1);
}

/* ARGSUSED */
static gboolean
sigexit_ioch_func(GIOChannel *source, GIOCondition condition,
    gpointer user_data)
{
    gchar   buf[1];
    gsize   bytes_read;
    GError  *error = NULL;

    if (g_io_channel_read_chars(source, buf, 1, &bytes_read, &error) !=
        G_IO_STATUS_NORMAL) {
        dprintf("g_io_channel_read_chars failed %s", error->message);
        g_error_free(error);
        return (TRUE);
    }

    dprintf("signal to exit\n");

    rmm_unmount_all();

    g_main_loop_quit(mainloop);

    return (TRUE);
}

static managed_volume_t *
rmm_managed_alloc(LibHalContext *ctx, const char *udi)
{
    managed_volume_t *v;

    if ((v = calloc(1, sizeof (managed_volume_t))) == NULL) {
        return (NULL);
    }
    if ((v->udi = strdup(udi)) == NULL) {
        free(v);
        return (NULL);
    }
    if (!rmm_volume_aa_from_prop(ctx, udi, NULL, &v->aa)) {
        free(v->udi);
        free(v);
        return (NULL);
    }

    return (v);
}

static void
rmm_managed_free(managed_volume_t *v)
{
    rmm_volume_aa_free(&v->aa);
    free(v->udi);
    free(v);
}

static gint
rmm_managed_compare_udi(gconstpointer a, gconstpointer b)
{
    const managed_volume_t *va = a;
    const char *udi = b;

    return (strcmp(va->udi, udi));
}

static boolean_t
volume_should_mount(const char *udi)
{
    char    *storage_device = NULL;
    int ret = B_FALSE;

    if (libhal_device_get_property_bool(hal_ctx, udi,
        "volume.ignore", NULL)) {
        goto out;
    }

    /* get the backing storage device */
    if (!(storage_device = libhal_device_get_property_string(hal_ctx, udi,
        "block.storage_device", NULL))) {
        dprintf("cannot get block.storage_device\n");
        goto out;
    }

    /* we handle either removable or hotpluggable */
    if (!libhal_device_get_property_bool(hal_ctx, storage_device,
        "storage.removable", NULL) &&
        !libhal_device_get_property_bool(hal_ctx, storage_device,
        "storage.hotpluggable", NULL)) {
        goto out;
    }

    /* ignore if claimed by another volume manager */
    if (libhal_device_get_property_bool(hal_ctx, storage_device,
        "info.claimed", NULL)) {
        goto out;
    }

    ret = B_TRUE;

out:
    libhal_free_string(storage_device);
    return (ret);
}

static void
volume_added(const char *udi)
{
    GSList      *l;
    managed_volume_t *v;

    dprintf("volume added %s\n", udi);

    l = g_slist_find_custom(managed_volumes, udi, rmm_managed_compare_udi);
    v = (l != NULL) ? l->data : NULL;

    if (v != NULL) {
        dprintf("already managed %s\n", udi);
        return;
    }
    if (!volume_should_mount(udi)) {
        dprintf("should not mount %s\n", udi);
        return;
    }
    if ((v = rmm_managed_alloc(hal_ctx, udi)) == NULL) {
        return;
    }
    if (rmm_action(hal_ctx, udi, INSERT, &v->aa, 0, 0, 0)) {
        v->my = B_TRUE;
        managed_volumes = g_slist_prepend(managed_volumes, v);
    } else {
        dprintf("rmm_action failed %s\n", udi);
        rmm_managed_free(v);
    }
}

static void
volume_removed(const char *udi)
{
    GSList      *l;
    managed_volume_t *v;

    dprintf("volume removed %s\n", udi);

    l = g_slist_find_custom(managed_volumes, udi, rmm_managed_compare_udi);
    v = (l != NULL) ? l->data : NULL;
    if (v == NULL) {
        return;
    }

    /* HAL will unmount, just do the vold legacy stuff */
    v->aa.aa_action = EJECT;
    (void) vold_postprocess(hal_ctx, udi, &v->aa);

    rmm_managed_free(v);
    managed_volumes = g_slist_delete_link(managed_volumes, l);
}

/* ARGSUSED */
static void
rmm_device_added(LibHalContext *ctx, const char *udi)
{
    if (libhal_device_query_capability(hal_ctx, udi, "volume", NULL)) {
        volume_added(udi);
    }
}

/* ARGSUSED */
static void
rmm_device_removed(LibHalContext *ctx, const char *udi)
{
    if (libhal_device_query_capability(hal_ctx, udi, "volume", NULL)) {
        volume_removed(udi);
    }
}

/* ARGSUSED */
static void
rmm_property_modified(LibHalContext *ctx, const char *udi, const char *key,
    dbus_bool_t is_removed, dbus_bool_t is_added)
{
    DBusError       error;
    GSList          *l;
    managed_volume_t    *v;
    boolean_t       is_mounted;

    if (strcmp(key, "volume.is_mounted") != 0) {
        return;
    }
    is_mounted = libhal_device_get_property_bool(hal_ctx, udi, key, NULL);

    l = g_slist_find_custom(managed_volumes, udi, rmm_managed_compare_udi);
    v = (l != NULL) ? l->data : NULL;

    if (is_mounted) {
        dprintf("Mounted: %s\n", udi);

        if (v != NULL) {
            /* volume mounted by us is already taken care of */
            if (v->my) {
                return;
            }
        } else {
            if ((v = rmm_managed_alloc(ctx, udi)) == NULL) {
                return;
            }
            managed_volumes = g_slist_prepend(managed_volumes, v);
        }

        v->aa.aa_action = INSERT;
        (void) vold_postprocess(hal_ctx, udi, &v->aa);

    } else {
        dprintf("Unmounted: %s\n", udi);

        if (v == NULL) {
            return;
        }

        v->aa.aa_action = EJECT;
        (void) vold_postprocess(hal_ctx, udi, &v->aa);

        rmm_managed_free(v);
        managed_volumes = g_slist_delete_link(managed_volumes, l);
    }
}

static void
storage_eject_pressed(const char *udi)
{
    DBusError   error;

    /* ignore if disabled via SMF or claimed by another volume manager */
    if (!rmm_prop_eject_button ||
        libhal_device_get_property_bool(hal_ctx, udi, "info.claimed",
        NULL)) {
        return;
    }

    dbus_error_init(&error);
    (void) rmm_hal_eject(hal_ctx, udi, &error);
    rmm_dbus_error_free(&error);
}

/* ARGSUSED */
static void
rmm_device_condition(LibHalContext *ctx, const char *udi,
    const char *name, const char *detail)
{
    if ((strcmp(name, "EjectPressed") == 0) &&
        libhal_device_query_capability(hal_ctx, udi, "storage", NULL)) {
        storage_eject_pressed(udi);
    }
}

/*
 * Mount all mountable volumes
 */
static void
rmm_mount_all()
{
    DBusError   error;
    char        **udis = NULL;
    int     num_udis;
    int     i;
    managed_volume_t *v;

    dbus_error_init(&error);

    /* get all volumes */
    if ((udis = libhal_find_device_by_capability(hal_ctx, "volume",
        &num_udis, &error)) == NULL) {
        dprintf("mount_all: no volumes found\n");
        goto out;
    }

    for (i = 0; i < num_udis; i++) {
        /* skip if already mounted */
        if (libhal_device_get_property_bool(hal_ctx, udis[i],
            "volume.is_mounted", NULL)) {
            dprintf("mount_all: %s already mounted\n", udis[i]);
            continue;
        }
        if (!volume_should_mount(udis[i])) {
            continue;
        }
        if ((v = rmm_managed_alloc(hal_ctx, udis[i])) == NULL) {
            continue;
        }
        if (rmm_action(hal_ctx, udis[i], INSERT, &v->aa, 0, 0, 0)) {
            v->my = B_TRUE;
            managed_volumes = g_slist_prepend(managed_volumes, v);
        } else {
            rmm_managed_free(v);
        }
    }

out:
    if (udis != NULL) {
        libhal_free_string_array(udis);
    }
    rmm_dbus_error_free(&error);
}

/*
 * Mount all volumes mounted by this program
 */
static void
rmm_unmount_all()
{
    GSList      *i;
    managed_volume_t *v;

    for (i = managed_volumes; i != NULL; i = managed_volumes) {
        v = (managed_volume_t *)i->data;

        if (v->my && libhal_device_get_property_bool(hal_ctx, v->udi,
            "volume.is_mounted", NULL)) {
            (void) rmm_action(hal_ctx, v->udi, UNMOUNT,
                &v->aa, 0, 0, 0);
        }

        managed_volumes = g_slist_remove(managed_volumes, v);
        rmm_managed_free(v);
    }
}

int
main(int argc, char **argv)
{
    vold_init(argc, argv);

    return (rmvolmgr(argc, argv));
}