--- /dev/null
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mount.h>
+#include <sys/wait.h>
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+#include <errno.h>
+
+#include <linux/limits.h>
+#include <linux/auto_fs4.h>
+
+#include <libubox/uloop.h>
+#include <libubox/vlist.h>
+#include <libubox/ulog.h>
+#include <libubox/avl-cmp.h>
+#include <libubus.h>
+
+#include "libfstools/libfstools.h"
+
+#define AUTOFS_MOUNT_PATH "/tmp/run/blockd/"
+#define AUTOFS_TIMEOUT 30
+#define AUTOFS_EXPIRE_TIMER (5 * 1000)
+
+struct device {
+ struct vlist_node node;
+ struct blob_attr *msg;
+ char *name;
+ char *target;
+ int autofs;
+ int anon;
+};
+
+static struct uloop_fd fd_autofs_read;
+static int fd_autofs_write = 0;
+static struct ubus_auto_conn conn;
+struct blob_buf bb = { 0 };
+
+enum {
+ MOUNT_UUID,
+ MOUNT_LABEL,
+ MOUNT_ENABLE,
+ MOUNT_TARGET,
+ MOUNT_DEVICE,
+ MOUNT_OPTIONS,
+ MOUNT_AUTOFS,
+ MOUNT_ANON,
+ MOUNT_REMOVE,
+ __MOUNT_MAX
+};
+
+static const struct blobmsg_policy mount_policy[__MOUNT_MAX] = {
+ [MOUNT_UUID] = { .name = "uuid", .type = BLOBMSG_TYPE_STRING },
+ [MOUNT_LABEL] = { .name = "label", .type = BLOBMSG_TYPE_STRING },
+ [MOUNT_DEVICE] = { .name = "device", .type = BLOBMSG_TYPE_STRING },
+ [MOUNT_TARGET] = { .name = "target", .type = BLOBMSG_TYPE_STRING },
+ [MOUNT_OPTIONS] = { .name = "options", .type = BLOBMSG_TYPE_STRING },
+ [MOUNT_ENABLE] = { .name = "enabled", .type = BLOBMSG_TYPE_INT32 },
+ [MOUNT_AUTOFS] = { .name = "autofs", .type = BLOBMSG_TYPE_INT32 },
+ [MOUNT_ANON] = { .name = "anon", .type = BLOBMSG_TYPE_INT32 },
+ [MOUNT_REMOVE] = { .name = "remove", .type = BLOBMSG_TYPE_INT32 },
+};
+
+static char*
+_find_mount_point(char *device)
+{
+ char dev[32] = { 0 };
+
+ snprintf(dev, sizeof(dev), "/dev/%s", device);
+
+ return find_mount_point(dev, 0);
+}
+
+static int
+block(char *cmd, char *action, char *device)
+{
+ pid_t pid = fork();
+ int ret = -1;
+ int status;
+ char *argv[5] = { 0 };
+ int a = 0;
+
+ switch (pid) {
+ case -1:
+ ULOG_ERR("failed to fork block process\n");
+ break;
+
+ case 0:
+ argv[a++] = "/sbin/block";
+ argv[a++] = cmd;
+ argv[a++] = action;
+ argv[a++] = device;
+ execvp(argv[0], argv);
+ ULOG_ERR("failed to spawn %s %s %s\n", *argv, action, device);
+ exit(-1);
+
+ default:
+ waitpid(pid, &status, 0);
+ ret = WEXITSTATUS(status);
+ if (ret)
+ ULOG_ERR("failed to run block. %s/%s\n", action, device);
+ break;
+ }
+
+ return ret;
+}
+
+static void
+device_free(struct device *device)
+{
+ struct blob_attr *data[__MOUNT_MAX];
+ char *target = NULL;
+ char *path = NULL, _path[64], *mp;
+
+ blobmsg_parse(mount_policy, __MOUNT_MAX, data,
+ blob_data(device->msg), blob_len(device->msg));
+
+ if (data[MOUNT_AUTOFS]) {
+ target = device->target;
+ snprintf(_path, sizeof(_path), "/tmp/run/blockd/%s",
+ blobmsg_get_string(data[MOUNT_DEVICE]));
+ path = _path;
+ } else {
+ path = target = device->target;
+ }
+
+ mp = _find_mount_point(device->name);
+ if (path && mp)
+ if (umount2(path, MNT_DETACH))
+ ULOG_ERR("failed to unmount %s\n", path);
+ free(mp);
+
+ if (!target)
+ return;
+
+ if (data[MOUNT_AUTOFS])
+ unlink(target);
+ else
+ rmdir(target);
+}
+
+static void
+device_add(struct device *device)
+{
+ struct blob_attr *data[__MOUNT_MAX];
+ char path[64];
+
+ blobmsg_parse(mount_policy, __MOUNT_MAX, data,
+ blob_data(device->msg), blob_len(device->msg));
+
+ if (!data[MOUNT_AUTOFS])
+ return;
+
+ snprintf(path, sizeof(path), "/tmp/run/blockd/%s",
+ blobmsg_get_string(data[MOUNT_DEVICE]));
+ if (symlink(path, device->target))
+ ULOG_ERR("failed to symlink %s->%s\n", device->target, path);
+}
+
+static int
+device_move(struct device *device_o, struct device *device_n)
+{
+ char path[64];
+
+ if (device_o->autofs != device_n->autofs)
+ return -1;
+
+ if (device_o->anon || device_n->anon)
+ return -1;
+
+ if (device_o->autofs) {
+ unlink(device_o->target);
+ snprintf(path, sizeof(path), "/tmp/run/blockd/%s", device_n->name);
+ if (symlink(path, device_n->target))
+ ULOG_ERR("failed to symlink %s->%s\n", device_n->target, path);
+ } else {
+ mkdir(device_n->target, 0755);
+ if (mount(device_o->target, device_n->target, NULL, MS_MOVE, NULL))
+ rmdir(device_n->target);
+ else
+ rmdir(device_o->target);
+ }
+
+ return 0;
+}
+
+static void
+devices_update_cb(struct vlist_tree *tree, struct vlist_node *node_new,
+ struct vlist_node *node_old)
+{
+ struct device *device_o = NULL, *device_n = NULL;
+
+ if (node_old)
+ device_o = container_of(node_old, struct device, node);
+
+ if (node_new)
+ device_n = container_of(node_new, struct device, node);
+
+ if (device_o && device_n) {
+ if (device_move(device_o, device_n)) {
+ device_free(device_o);
+ device_add(device_n);
+ if (!device_n->autofs)
+ block("mount", NULL, NULL);
+ }
+ } else if (device_n) {
+ device_add(device_n);
+ } else {
+ device_free(device_o);
+ }
+
+ if (device_o)
+ free(device_o);
+}
+
+VLIST_TREE(devices, avl_strcmp, devices_update_cb, false, false);
+
+static int
+block_hotplug(struct ubus_context *ctx, struct ubus_object *obj,
+ struct ubus_request_data *req, const char *method,
+ struct blob_attr *msg)
+{
+ struct blob_attr *data[__MOUNT_MAX];
+ struct device *device;
+ struct blob_attr *_msg;
+ char *devname, *_name;
+ char *target = NULL, *__target;
+ char _target[32];
+
+ blobmsg_parse(mount_policy, __MOUNT_MAX, data, blob_data(msg), blob_len(msg));
+
+ if (!data[MOUNT_DEVICE])
+ return UBUS_STATUS_INVALID_ARGUMENT;
+
+ devname = blobmsg_get_string(data[MOUNT_DEVICE]);
+
+ if (data[MOUNT_TARGET]) {
+ target = blobmsg_get_string(data[MOUNT_TARGET]);
+ } else {
+ snprintf(_target, sizeof(_target), "/mnt/%s",
+ blobmsg_get_string(data[MOUNT_DEVICE]));
+ target = _target;
+ }
+
+ if (data[MOUNT_REMOVE])
+ device = vlist_find(&devices, devname, device, node);
+ else
+ device = calloc_a(sizeof(*device), &_msg, blob_raw_len(msg),
+ &_name, strlen(devname) + 1, &__target, strlen(target) + 1);
+
+ if (!device)
+ return UBUS_STATUS_UNKNOWN_ERROR;
+
+ vlist_update(&devices);
+ if (data[MOUNT_REMOVE]) {
+ vlist_delete(&devices, &device->node);
+ } else {
+ if (data[MOUNT_AUTOFS])
+ device->autofs = blobmsg_get_u32(data[MOUNT_AUTOFS]);
+ else
+ device->autofs = 0;
+ if (data[MOUNT_ANON])
+ device->anon = blobmsg_get_u32(data[MOUNT_ANON]);
+ else
+ device->anon = 0;
+ device->msg = _msg;
+ memcpy(_msg, msg, blob_raw_len(msg));
+ device->name = _name;
+ strcpy(_name, devname);
+ device->target = __target;
+ strcpy(__target, target);
+ vlist_add(&devices, &device->node, blobmsg_get_string(data[MOUNT_DEVICE]));
+ }
+ vlist_flush(&devices);
+
+ return 0;
+}
+
+static int
+block_info(struct ubus_context *ctx, struct ubus_object *obj,
+ struct ubus_request_data *req, const char *method,
+ struct blob_attr *msg)
+{
+ struct device *device;
+ void *a;
+
+ blob_buf_init(&bb, 0);
+ a = blobmsg_open_array(&bb, "devices");
+ vlist_for_each_element(&devices, device, node) {
+ void *t = blobmsg_open_table(&bb, "");
+ struct blob_attr *v;
+ char *mp;
+ int rem;
+
+ blob_for_each_attr(v, device->msg, rem)
+ blobmsg_add_blob(&bb, v);
+
+ mp = _find_mount_point(device->name);
+ if (mp) {
+ blobmsg_add_string(&bb, "mount", mp);
+ free(mp);
+ }
+ blobmsg_close_table(&bb, t);
+ }
+ blobmsg_close_array(&bb, a);
+ ubus_send_reply(ctx, req, bb.head);
+
+ return 0;
+}
+
+static const struct ubus_method block_methods[] = {
+ UBUS_METHOD("hotplug", block_hotplug, mount_policy),
+ UBUS_METHOD_NOARG("info", block_info),
+};
+
+static struct ubus_object_type block_object_type =
+ UBUS_OBJECT_TYPE("block", block_methods);
+
+static struct ubus_object block_object = {
+ .name = "block",
+ .type = &block_object_type,
+ .methods = block_methods,
+ .n_methods = ARRAY_SIZE(block_methods),
+};
+
+static void
+ubus_connect_handler(struct ubus_context *ctx)
+{
+ int ret;
+
+ ret = ubus_add_object(ctx, &block_object);
+ if (ret)
+ fprintf(stderr, "Failed to add object: %s\n", ubus_strerror(ret));
+}
+
+static int autofs_umount(void)
+{
+ umount2(AUTOFS_MOUNT_PATH, MNT_DETACH);
+ return 0;
+}
+
+static void autofs_read_handler(struct uloop_fd *u, unsigned int events)
+{
+ union autofs_v5_packet_union pktu;
+ const struct autofs_v5_packet *pkt;
+ int cmd = AUTOFS_IOC_READY;
+ struct stat st;
+
+ while (read(u->fd, &pktu, sizeof(pktu)) == -1) {
+ if (errno != EINTR)
+ return;
+ continue;
+ }
+
+ if (pktu.hdr.type != autofs_ptype_missing_indirect) {
+ ULOG_ERR("unknown packet type %d\n", pktu.hdr.type);
+ return;
+ }
+
+ pkt = &pktu.missing_indirect;
+ ULOG_ERR("kernel is requesting a mount -> %s\n", pkt->name);
+ if (lstat(pkt->name, &st) == -1)
+ if (block("autofs", "add", (char *)pkt->name))
+ cmd = AUTOFS_IOC_FAIL;
+
+ if (ioctl(fd_autofs_write, cmd, pkt->wait_queue_token) < 0)
+ ULOG_ERR("failed to report back to kernel\n");
+}
+
+static void autofs_expire(struct uloop_timeout *t)
+{
+ struct autofs_packet_expire pkt;
+
+ while (ioctl(fd_autofs_write, AUTOFS_IOC_EXPIRE, &pkt) == 0)
+ block("autofs", "remove", pkt.name);
+
+ uloop_timeout_set(t, AUTOFS_EXPIRE_TIMER);
+}
+
+struct uloop_timeout autofs_expire_timer = {
+ .cb = autofs_expire,
+};
+
+static int autofs_mount(void)
+{
+ int autofs_timeout = AUTOFS_TIMEOUT;
+ int kproto_version;
+ int pipefd[2];
+ char source[64];
+ char opts[64];
+
+ if (pipe(pipefd) < 0) {
+ ULOG_ERR("failed to get kernel pipe\n");
+ return -1;
+ }
+
+ snprintf(source, sizeof(source), "mountd(pid%u)", getpid());
+ snprintf(opts, sizeof(opts), "fd=%d,pgrp=%u,minproto=5,maxproto=5", pipefd[1], (unsigned) getpgrp());
+ mkdir(AUTOFS_MOUNT_PATH, 0555);
+ if (mount(source, AUTOFS_MOUNT_PATH, "autofs", 0, opts)) {
+ ULOG_ERR("unable to mount autofs on %s\n", AUTOFS_MOUNT_PATH);
+ close(pipefd[0]);
+ close(pipefd[1]);
+ return -1;
+ }
+ close(pipefd[1]);
+ fd_autofs_read.fd = pipefd[0];
+ fd_autofs_read.cb = autofs_read_handler;
+ uloop_fd_add(&fd_autofs_read, ULOOP_READ);
+
+ fd_autofs_write = open(AUTOFS_MOUNT_PATH, O_RDONLY);
+ if(fd_autofs_write < 0) {
+ autofs_umount();
+ ULOG_ERR("failed to open direcory\n");
+ return -1;
+ }
+
+ ioctl(fd_autofs_write, AUTOFS_IOC_PROTOVER, &kproto_version);
+ if (kproto_version != 5) {
+ ULOG_ERR("only kernel protocol version 5 is tested. You have %d.\n",
+ kproto_version);
+ exit(1);
+ }
+ if (ioctl(fd_autofs_write, AUTOFS_IOC_SETTIMEOUT, &autofs_timeout))
+ ULOG_ERR("failed to set autofs timeout\n");
+
+ uloop_timeout_set(&autofs_expire_timer, AUTOFS_EXPIRE_TIMER);
+
+ fcntl(fd_autofs_write, F_SETFD, fcntl(fd_autofs_write, F_GETFD) | FD_CLOEXEC);
+ fcntl(fd_autofs_read.fd, F_SETFD, fcntl(fd_autofs_read.fd, F_GETFD) | FD_CLOEXEC);
+
+ return 0;
+}
+
+static void blockd_startup(struct uloop_timeout *t)
+{
+ block("autofs", "start", NULL);
+}
+
+struct uloop_timeout startup = {
+ .cb = blockd_startup,
+};
+
+int main(int argc, char **argv)
+{
+ ulog_open(ULOG_SYSLOG | ULOG_STDIO, LOG_DAEMON, "blockd");
+ uloop_init();
+
+ autofs_mount();
+
+ conn.cb = ubus_connect_handler;
+ ubus_auto_connect(&conn);
+
+ uloop_timeout_set(&startup, 1000);
+
+ uloop_run();
+ uloop_done();
+
+ autofs_umount();
+
+ vlist_flush_all(&devices);
+
+ return 0;
+}
projects / project / fstools.git / blobdiff