-/*
- * nfsdcld.c -- NFSv4 client name tracking daemon
- *
- * Copyright (C) 2011 Red Hat, Jeff Layton <jlayton@redhat.com>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor,
- * Boston, MA 02110-1301, USA.
- */
-
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif /* HAVE_CONFIG_H */
-
-#include <errno.h>
-#include <event.h>
-#include <stdbool.h>
-#include <getopt.h>
-#include <string.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <libgen.h>
-#include <sys/inotify.h>
-#ifdef HAVE_SYS_CAPABILITY_H
-#include <sys/prctl.h>
-#include <sys/capability.h>
-#endif
-
-#include "xlog.h"
-#include "nfslib.h"
-#include "cld.h"
-#include "sqlite.h"
-
-#ifndef PIPEFS_DIR
-#define PIPEFS_DIR NFS_STATEDIR "/rpc_pipefs"
-#endif
-
-#define DEFAULT_CLD_PATH PIPEFS_DIR "/nfsd/cld"
-
-#ifndef CLD_DEFAULT_STORAGEDIR
-#define CLD_DEFAULT_STORAGEDIR NFS_STATEDIR "/nfsdcld"
-#endif
-
-#define UPCALL_VERSION 1
-
-/* private data structures */
-struct cld_client {
- int cl_fd;
- struct event cl_event;
- struct cld_msg cl_msg;
-};
-
-/* global variables */
-static char *pipepath = DEFAULT_CLD_PATH;
-static int inotify_fd = -1;
-static struct event pipedir_event;
-
-static struct option longopts[] =
-{
- { "help", 0, NULL, 'h' },
- { "foreground", 0, NULL, 'F' },
- { "debug", 0, NULL, 'd' },
- { "pipe", 1, NULL, 'p' },
- { "storagedir", 1, NULL, 's' },
- { NULL, 0, 0, 0 },
-};
-
-/* forward declarations */
-static void cldcb(int UNUSED(fd), short which, void *data);
-
-static void
-usage(char *progname)
-{
- printf("%s [ -hFd ] [ -p pipe ] [ -s dir ]\n", progname);
-}
-
-static int
-cld_set_caps(void)
-{
- int ret = 0;
-#ifdef HAVE_SYS_CAPABILITY_H
- unsigned long i;
- cap_t caps;
-
- if (getuid() != 0) {
- xlog(L_ERROR, "Not running as root. Daemon won't be able to "
- "open the pipe after dropping capabilities!");
- return -EINVAL;
- }
-
- /* prune the bounding set to nothing */
- for (i = 0; prctl(PR_CAPBSET_READ, i, 0, 0, 0) >= 0 ; ++i) {
- ret = prctl(PR_CAPBSET_DROP, i, 0, 0, 0);
- if (ret) {
- xlog(L_ERROR, "Unable to prune capability %lu from "
- "bounding set: %m", i);
- return -errno;
- }
- }
-
- /* get a blank capset */
- caps = cap_init();
- if (caps == NULL) {
- xlog(L_ERROR, "Unable to get blank capability set: %m");
- return -errno;
- }
-
- /* reset the process capabilities */
- if (cap_set_proc(caps) != 0) {
- xlog(L_ERROR, "Unable to set process capabilities: %m");
- ret = -errno;
- }
- cap_free(caps);
-#endif
- return ret;
-}
-
-#define INOTIFY_EVENT_MAX (sizeof(struct inotify_event) + NAME_MAX)
-
-static int
-cld_pipe_open(struct cld_client *clnt)
-{
- int fd;
-
- xlog(D_GENERAL, "%s: opening upcall pipe %s", __func__, pipepath);
- fd = open(pipepath, O_RDWR, 0);
- if (fd < 0) {
- xlog(D_GENERAL, "%s: open of %s failed: %m", __func__, pipepath);
- return -errno;
- }
-
- if (clnt->cl_event.ev_flags & EVLIST_INIT)
- event_del(&clnt->cl_event);
- if (clnt->cl_fd >= 0)
- close(clnt->cl_fd);
-
- clnt->cl_fd = fd;
- event_set(&clnt->cl_event, clnt->cl_fd, EV_READ, cldcb, clnt);
- /* event_add is done by the caller */
- return 0;
-}
-
-static void
-cld_inotify_cb(int UNUSED(fd), short which, void *data)
-{
- int ret;
- size_t elen;
- ssize_t rret;
- char evbuf[INOTIFY_EVENT_MAX];
- char *dirc = NULL, *pname;
- struct inotify_event *event = (struct inotify_event *)evbuf;
- struct cld_client *clnt = data;
-
- if (which != EV_READ)
- return;
-
- xlog(D_GENERAL, "%s: called for EV_READ", __func__);
-
- dirc = strndup(pipepath, PATH_MAX);
- if (!dirc) {
- xlog(L_ERROR, "%s: unable to allocate memory", __func__);
- goto out;
- }
-
- rret = read(inotify_fd, evbuf, INOTIFY_EVENT_MAX);
- if (rret < 0) {
- xlog(L_ERROR, "%s: read from inotify fd failed: %m", __func__);
- goto out;
- }
-
- /* check to see if we have a filename in the evbuf */
- if (!event->len) {
- xlog(D_GENERAL, "%s: no filename in inotify event", __func__);
- goto out;
- }
-
- pname = basename(dirc);
- elen = strnlen(event->name, event->len);
-
- /* does the filename match our pipe? */
- if (strlen(pname) != elen || memcmp(pname, event->name, elen)) {
- xlog(D_GENERAL, "%s: wrong filename (%s)", __func__,
- event->name);
- goto out;
- }
-
- ret = cld_pipe_open(clnt);
- switch (ret) {
- case 0:
- /* readd the event for the cl_event pipe */
- event_add(&clnt->cl_event, NULL);
- break;
- case -ENOENT:
- /* pipe must have disappeared, wait for it to come back */
- goto out;
- default:
- /* anything else is fatal */
- xlog(L_FATAL, "%s: unable to open new pipe (%d). Aborting.",
- ret, __func__);
- exit(ret);
- }
-
-out:
- event_add(&pipedir_event, NULL);
- free(dirc);
-}
-
-static int
-cld_inotify_setup(void)
-{
- int ret;
- char *dirc, *dname;
-
- dirc = strndup(pipepath, PATH_MAX);
- if (!dirc) {
- xlog_err("%s: unable to allocate memory", __func__);
- ret = -ENOMEM;
- goto out_free;
- }
-
- dname = dirname(dirc);
-
- inotify_fd = inotify_init();
- if (inotify_fd < 0) {
- xlog_err("%s: inotify_init failed: %m", __func__);
- ret = -errno;
- goto out_free;
- }
-
- ret = inotify_add_watch(inotify_fd, dname, IN_CREATE);
- if (ret < 0) {
- xlog_err("%s: inotify_add_watch failed: %m", __func__);
- ret = -errno;
- goto out_err;
- }
-
-out_free:
- free(dirc);
- return 0;
-out_err:
- close(inotify_fd);
- goto out_free;
-}
-
-/*
- * Set an inotify watch on the directory that should contain the pipe, and then
- * try to open it. If it fails with anything but -ENOENT, return the error
- * immediately.
- *
- * If it succeeds, then set up the pipe event handler. At that point, set up
- * the inotify event handler and go ahead and return success.
- */
-static int
-cld_pipe_init(struct cld_client *clnt)
-{
- int ret;
-
- xlog(D_GENERAL, "%s: init pipe handlers", __func__);
-
- ret = cld_inotify_setup();
- if (ret != 0)
- goto out;
-
- clnt->cl_fd = -1;
- ret = cld_pipe_open(clnt);
- switch (ret) {
- case 0:
- /* add the event and we're good to go */
- event_add(&clnt->cl_event, NULL);
- break;
- case -ENOENT:
- /* ignore this error -- cld_inotify_cb will handle it */
- ret = 0;
- break;
- default:
- /* anything else is fatal */
- close(inotify_fd);
- goto out;
- }
-
- /* set event for inotify read */
- event_set(&pipedir_event, inotify_fd, EV_READ, cld_inotify_cb, clnt);
- event_add(&pipedir_event, NULL);
-out:
- return ret;
-}
-
-static void
-cld_not_implemented(struct cld_client *clnt)
-{
- int ret;
- ssize_t bsize, wsize;
- struct cld_msg *cmsg = &clnt->cl_msg;
-
- xlog(D_GENERAL, "%s: downcalling with not implemented error", __func__);
-
- /* set up reply */
- cmsg->cm_status = -EOPNOTSUPP;
-
- bsize = sizeof(*cmsg);
-
- wsize = atomicio((void *)write, clnt->cl_fd, cmsg, bsize);
- if (wsize != bsize)
- xlog(L_ERROR, "%s: problem writing to cld pipe (%ld): %m",
- __func__, wsize);
-
- /* reopen pipe, just to be sure */
- ret = cld_pipe_open(clnt);
- if (ret) {
- xlog(L_FATAL, "%s: unable to reopen pipe: %d", __func__, ret);
- exit(ret);
- }
-}
-
-static void
-cld_create(struct cld_client *clnt)
-{
- int ret;
- ssize_t bsize, wsize;
- struct cld_msg *cmsg = &clnt->cl_msg;
-
- xlog(D_GENERAL, "%s: create client record.", __func__);
-
- ret = sqlite_insert_client(cmsg->cm_u.cm_name.cn_id,
- cmsg->cm_u.cm_name.cn_len);
-
- cmsg->cm_status = ret ? -EREMOTEIO : ret;
-
- bsize = sizeof(*cmsg);
-
- xlog(D_GENERAL, "Doing downcall with status %d", cmsg->cm_status);
- wsize = atomicio((void *)write, clnt->cl_fd, cmsg, bsize);
- if (wsize != bsize) {
- xlog(L_ERROR, "%s: problem writing to cld pipe (%ld): %m",
- __func__, wsize);
- ret = cld_pipe_open(clnt);
- if (ret) {
- xlog(L_FATAL, "%s: unable to reopen pipe: %d",
- __func__, ret);
- exit(ret);
- }
- }
-}
-
-static void
-cld_remove(struct cld_client *clnt)
-{
- int ret;
- ssize_t bsize, wsize;
- struct cld_msg *cmsg = &clnt->cl_msg;
-
- xlog(D_GENERAL, "%s: remove client record.", __func__);
-
- ret = sqlite_remove_client(cmsg->cm_u.cm_name.cn_id,
- cmsg->cm_u.cm_name.cn_len);
-
- cmsg->cm_status = ret ? -EREMOTEIO : ret;
-
- bsize = sizeof(*cmsg);
-
- xlog(D_GENERAL, "%s: downcall with status %d", __func__,
- cmsg->cm_status);
- wsize = atomicio((void *)write, clnt->cl_fd, cmsg, bsize);
- if (wsize != bsize) {
- xlog(L_ERROR, "%s: problem writing to cld pipe (%ld): %m",
- __func__, wsize);
- ret = cld_pipe_open(clnt);
- if (ret) {
- xlog(L_FATAL, "%s: unable to reopen pipe: %d",
- __func__, ret);
- exit(ret);
- }
- }
-}
-
-static void
-cld_check(struct cld_client *clnt)
-{
- int ret;
- ssize_t bsize, wsize;
- struct cld_msg *cmsg = &clnt->cl_msg;
-
- xlog(D_GENERAL, "%s: check client record", __func__);
-
- ret = sqlite_check_client(cmsg->cm_u.cm_name.cn_id,
- cmsg->cm_u.cm_name.cn_len);
-
- /* set up reply */
- cmsg->cm_status = ret ? -EACCES : ret;
-
- bsize = sizeof(*cmsg);
-
- xlog(D_GENERAL, "%s: downcall with status %d", __func__,
- cmsg->cm_status);
- wsize = atomicio((void *)write, clnt->cl_fd, cmsg, bsize);
- if (wsize != bsize) {
- xlog(L_ERROR, "%s: problem writing to cld pipe (%ld): %m",
- __func__, wsize);
- ret = cld_pipe_open(clnt);
- if (ret) {
- xlog(L_FATAL, "%s: unable to reopen pipe: %d",
- __func__, ret);
- exit(ret);
- }
- }
-}
-
-static void
-cld_gracedone(struct cld_client *clnt)
-{
- int ret;
- ssize_t bsize, wsize;
- struct cld_msg *cmsg = &clnt->cl_msg;
-
- xlog(D_GENERAL, "%s: grace done. cm_gracetime=%ld", __func__,
- cmsg->cm_u.cm_gracetime);
-
- ret = sqlite_remove_unreclaimed(cmsg->cm_u.cm_gracetime);
-
- /* set up reply: downcall with 0 status */
- cmsg->cm_status = ret ? -EREMOTEIO : ret;
-
- bsize = sizeof(*cmsg);
-
- xlog(D_GENERAL, "Doing downcall with status %d", cmsg->cm_status);
- wsize = atomicio((void *)write, clnt->cl_fd, cmsg, bsize);
- if (wsize != bsize) {
- xlog(L_ERROR, "%s: problem writing to cld pipe (%ld): %m",
- __func__, wsize);
- ret = cld_pipe_open(clnt);
- if (ret) {
- xlog(L_FATAL, "%s: unable to reopen pipe: %d",
- __func__, ret);
- exit(ret);
- }
- }
-}
-
-static void
-cldcb(int UNUSED(fd), short which, void *data)
-{
- ssize_t len;
- struct cld_client *clnt = data;
- struct cld_msg *cmsg = &clnt->cl_msg;
-
- if (which != EV_READ)
- goto out;
-
- len = atomicio(read, clnt->cl_fd, cmsg, sizeof(*cmsg));
- if (len <= 0) {
- xlog(L_ERROR, "%s: pipe read failed: %m", __func__);
- cld_pipe_open(clnt);
- goto out;
- }
-
- if (cmsg->cm_vers != UPCALL_VERSION) {
- xlog(L_ERROR, "%s: unsupported upcall version: %hu",
- cmsg->cm_vers);
- cld_pipe_open(clnt);
- goto out;
- }
-
- switch(cmsg->cm_cmd) {
- case Cld_Create:
- cld_create(clnt);
- break;
- case Cld_Remove:
- cld_remove(clnt);
- break;
- case Cld_Check:
- cld_check(clnt);
- break;
- case Cld_GraceDone:
- cld_gracedone(clnt);
- break;
- default:
- xlog(L_WARNING, "%s: command %u is not yet implemented",
- __func__, cmsg->cm_cmd);
- cld_not_implemented(clnt);
- }
-out:
- event_add(&clnt->cl_event, NULL);
-}
-
-int
-main(int argc, char **argv)
-{
- char arg;
- int rc = 0;
- bool foreground = false;
- char *progname;
- char *storagedir = CLD_DEFAULT_STORAGEDIR;
- struct cld_client clnt;
-
- memset(&clnt, 0, sizeof(clnt));
-
- progname = strdup(basename(argv[0]));
- if (!progname) {
- fprintf(stderr, "%s: unable to allocate memory.\n", argv[0]);
- return 1;
- }
-
- event_init();
- xlog_syslog(0);
- xlog_stderr(1);
-
- /* process command-line options */
- while ((arg = getopt_long(argc, argv, "hdFp:s:", longopts,
- NULL)) != EOF) {
- switch (arg) {
- case 'd':
- xlog_config(D_ALL, 1);
- break;
- case 'F':
- foreground = true;
- break;
- case 'p':
- pipepath = optarg;
- break;
- case 's':
- storagedir = optarg;
- break;
- default:
- usage(progname);
- return 0;
- }
- }
-
-
- xlog_open(progname);
- if (!foreground) {
- xlog_syslog(1);
- xlog_stderr(0);
- rc = daemon(0, 0);
- if (rc) {
- xlog(L_ERROR, "Unable to daemonize: %m");
- goto out;
- }
- }
-
- /* drop all capabilities */
- rc = cld_set_caps();
- if (rc)
- goto out;
-
- /*
- * now see if the storagedir is writable by root w/o CAP_DAC_OVERRIDE.
- * If it isn't then give the user a warning but proceed as if
- * everything is OK. If the DB has already been created, then
- * everything might still work. If it doesn't exist at all, then
- * assume that the maindb init will be able to create it. Fail on
- * anything else.
- */
- if (access(storagedir, W_OK) == -1) {
- switch (errno) {
- case EACCES:
- xlog(L_WARNING, "Storage directory %s is not writable. "
- "Should be owned by root and writable "
- "by owner!", storagedir);
- break;
- case ENOENT:
- /* ignore and assume that we can create dir as root */
- break;
- default:
- xlog(L_ERROR, "Unexpected error when checking access "
- "on %s: %m", storagedir);
- rc = -errno;
- goto out;
- }
- }
-
- /* set up storage db */
- rc = sqlite_maindb_init(storagedir);
- if (rc) {
- xlog(L_ERROR, "Failed to open main database: %d", rc);
- goto out;
- }
-
- /* set up event handler */
- rc = cld_pipe_init(&clnt);
- if (rc)
- goto out;
-
- xlog(D_GENERAL, "%s: Starting event dispatch handler.", __func__);
- rc = event_dispatch();
- if (rc < 0)
- xlog(L_ERROR, "%s: event_dispatch failed: %m", __func__);
-
- close(clnt.cl_fd);
- close(inotify_fd);
-out:
- free(progname);
- return rc;
-}
projects / nfs-utils.git / commitdiff