Add sm-notify from SuSE

Not included in build yet.

2 files changed, 792 insertions, 0 deletions

diff --git a/utils/statd/sm-notify.8 b/utils/statd/sm-notify.8
new file mode 100644
index 0000000..29726d6
--- /dev/null
+++ b/utils/statd/sm-notify.8
@@ -0,0 +1,114 @@
+.\"
+.\" sm-notify(8)
+.\"
+.\" Copyright (C) 2004 Olaf Kirch <okir@suse.de>
+.TH sm-notify 8 "8 Mar 2004
+.SH NAME
+sm-notify \- Send out NSM reboot notifications
+.SH SYNOPSIS
+.BI "/sbin/sm-notify [-d] [-q] [-m " time "]
+.SH DESCRIPTION
+File locking over NFS requires a facility to notify peers in
+case of a reboot, so that clients can reclaim locks after
+a server crash, and/or
+servers can release locks held by the rebooted client.
+.PP
+This is a two-step process: during normal
+operations, a mechanism is required to keep track of which
+hosts need to be informed of a reboot. And of course,
+notifications need to be sent out during reboot.
+The protocol used for this is called NSM, for
+.IR "Network Status Monitor" .
+.PP
+Commonly, these two features are provided by the
+.B rpc.statd
+daemon.
+The SuSE Linux Kernel includes a kernel level implementation
+of
+.BR statd ", "
+which keeps track of the hosts that need notifications, and
+accepts reboot notifications.
+.PP
+This is complemented by the
+.B sm-notify
+application, which is responsible for sending out the reboot
+notifications.
+.SS Operation
+For each NFS client or server machine to be monitored,
+the kernel level
+.B statd
+creates a file in
+.BR /var/lib/nfs/sm ", "
+and removes the file if monitoring is no longer required.
+.PP
+When the machine is rebooted,
+.B sm-notify
+iterates through these files and notifies the peer
+.B statd
+server on those machines.
+.PP
+Each machine has an
+.I "NSM state" ,
+which is basically an integer counter that is incremented
+each time the machine reboots. This counter is stored
+in
+.BR /var/lib/nfs/state ,
+and updated by
+.BR sm-notify .
+.SH OPTIONS
+.TP
+.BI -m " failtime
+When notifying hosts,
+.B sm-notify
+will try to contact each host for up to 15 minutes,
+and will give up if unable to reach it within this time
+frame.
+.IP
+Using the
+.B -m
+option, you can override this. A value of 0 tells
+sm-notify to retry indefinitely; any other value is
+interpreted as the maximum retry time in minutes.
+.TP
+.BI -v " ipaddr
+This option tells
+.B sm-notify
+to bind to the specified
+.IR ipaddr ,
+so that all notification packets originate from this address.
+This is useful for NFS failover.
+.TP
+.BI -p " port
+instructs
+.B sm-notify
+to bind to the indicated IP
+.IR port
+number. If this option is not given, it will try to bind to
+a randomly chosen privileged port below 1024.
+.TP
+.B -q
+Be quiet. This suppresses all messages except error
+messages while collecting the list of hosts.
+.TP
+.B -n
+Do not update the NSM state. This is for testing only.
+.TP
+.B -d
+Enables debugging.
+By default,
+.B sm-notify
+forks and puts itself in the background after obtaining the
+list of hosts from
+.BR /var/lib/nfs/sm .
+.SH FILES
+.BR /var/lib/nfs/state
+.br
+.BR /var/lib/nfs/sm/*
+.br
+.BR /var/lib/nfs/sm.bak/*
+.SH SEE ALSO
+.BR rpc.nfsd(8),
+.BR portmap(8)
+.SH AUTHORS
+.br
+Olaf Kirch <okir@suse.de>
diff --git a/utils/statd/sm-notify.c b/utils/statd/sm-notify.c
new file mode 100644
index 0000000..7af0cea
--- /dev/null
+++ b/utils/statd/sm-notify.c
@@ -0,0 +1,678 @@
+/*
+ * Send NSM notify calls to all hosts listed in /var/lib/sm
+ *
+ * Copyright (C) 2004-2006 Olaf Kirch <okir@suse.de>
+ */
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/poll.h>
+#include <sys/param.h>
+#include <sys/syslog.h>
+#include <arpa/inet.h>
+#include <dirent.h>
+#include <time.h>
+#include <stdio.h>
+#include <getopt.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdarg.h>
+#include <netdb.h>
+#include <errno.h>
+
+#ifndef BASEDIR
+#define BASEDIR		"/var/lib/nfs"
+#endif
+
+#define _SM_STATE_PATH	BASEDIR "/state"
+#define	_SM_DIR_PATH	BASEDIR "/sm"
+#define	_SM_BAK_PATH	_SM_DIR_PATH ".bak"
+
+#define NSM_PROG	100024
+#define NSM_PROGRAM	100024
+#define NSM_VERSION	1
+#define NSM_TIMEOUT	2
+#define NSM_NOTIFY	6
+#define NSM_MAX_TIMEOUT	120	/* don't make this too big */
+#define MAXMSGSIZE	256
+
+typedef struct sockaddr_storage nsm_address;
+
+struct nsm_host {
+	struct nsm_host *	next;
+	char *			name;
+	char *			path;
+	nsm_address		addr;
+	time_t			last_used;
+	time_t			send_next;
+	unsigned int		timeout;
+	unsigned int		retries;
+	unsigned int		xid;
+};
+
+static char		nsm_hostname[256];
+static uint32_t		nsm_state;
+static int		opt_debug = 0;
+static int		opt_quiet = 0;
+static int		opt_update_state = 1;
+static unsigned int	opt_max_retry = 15 * 60;
+static char *		opt_srcaddr = 0;
+static uint16_t		opt_srcport = 0;
+static int		log_syslog = 0;
+
+static unsigned int	nsm_get_state(int);
+static void		notify(void);
+static void		notify_host(int, struct nsm_host *);
+static void		recv_reply(int);
+static void		backup_hosts(const char *, const char *);
+static void		get_hosts(const char *);
+static void		insert_host(struct nsm_host *);
+struct nsm_host *	find_host(uint32_t);
+static int		addr_parse(int, const char *, nsm_address *);
+static int		addr_get_port(nsm_address *);
+static void		addr_set_port(nsm_address *, int);
+static int		host_lookup(int, const char *, nsm_address *);
+void			nsm_log(int fac, const char *fmt, ...);
+
+static struct nsm_host *	hosts = NULL;
+
+int
+main(int argc, char **argv)
+{
+	int	c;
+
+	while ((c = getopt(argc, argv, "dm:np:v:q")) != -1) {
+		switch (c) {
+		case 'd':
+			opt_debug++;
+			break;
+		case 'm':
+			opt_max_retry = atoi(optarg) * 60;
+			break;
+		case 'n':
+			opt_update_state = 0;
+			break;
+		case 'p':
+			opt_srcport = atoi(optarg);
+			break;
+		case 'v':
+			opt_srcaddr = optarg;
+			break;
+		case 'q':
+			opt_quiet = 1;
+			break;
+		default:
+			goto usage;
+		}
+	}
+
+	if (optind < argc) {
+usage:		fprintf(stderr, "sm-notify [-d]\n");
+		return 1;
+	}
+
+	if (opt_srcaddr) {
+		strncpy(nsm_hostname, opt_srcaddr, sizeof(nsm_hostname)-1);
+	} else
+	if (gethostname(nsm_hostname, sizeof(nsm_hostname)) < 0) {
+		perror("gethostname");
+		return 1;
+	}
+
+	backup_hosts(_SM_DIR_PATH, _SM_BAK_PATH);
+	get_hosts(_SM_BAK_PATH);
+
+	if (!opt_debug) {
+		if (!opt_quiet)
+			printf("Backgrounding to notify hosts...\n");
+
+		openlog("sm-notify", LOG_PID, LOG_DAEMON);
+		log_syslog = 1;
+
+		if (daemon(0, 0) < 0) {
+			nsm_log(LOG_WARNING, "unable to background: %s",
+					strerror(errno));
+			return 1;
+		}
+
+		close(0);
+		close(1);
+		close(2);
+	}
+
+	/* Get and update the NSM state. This will call sync() */
+	nsm_state = nsm_get_state(opt_update_state);
+
+	notify();
+
+	if (hosts) {
+		struct nsm_host	*hp;
+
+		while ((hp = hosts) != 0) {
+			hosts = hp->next;
+			nsm_log(LOG_NOTICE,
+				"Unable to notify %s, giving up",
+				hp->name);
+		}
+		return 1;
+	}
+
+	return 0;
+}
+
+/*
+ * Notify hosts
+ */
+void
+notify(void)
+{
+	nsm_address local_addr;
+	time_t	failtime = 0;
+	int	sock = -1;
+
+	sock = socket(AF_INET, SOCK_DGRAM, 0);
+	if (sock < 0) {
+		perror("socket");
+		exit(1);
+	}
+	fcntl(sock, F_SETFL, O_NONBLOCK);
+
+	memset(&local_addr, 0, sizeof(local_addr));
+	local_addr.ss_family = AF_INET; /* Default to IPv4 */
+
+	/* Bind source IP if provided on command line */
+	if (opt_srcaddr) {
+		if (!addr_parse(AF_INET, opt_srcaddr, &local_addr)
+		 && !host_lookup(AF_INET, opt_srcaddr, &local_addr)) {
+			nsm_log(LOG_WARNING,
+				"Not a valid hostname or address: \"%s\"\n",
+				opt_srcaddr);
+			exit(1);
+		}
+		/* We know it's IPv4 at this point */
+	}
+
+	/* Use source port if provided on the command line,
+	 * otherwise use bindresvport */
+	if (opt_srcport) {
+		addr_set_port(&local_addr, opt_srcport);
+		if (bind(sock, (struct sockaddr *) &local_addr, sizeof(local_addr)) < 0) {
+			perror("bind");
+			exit(1);
+		}
+	} else {
+		(void) bindresvport(sock, (struct sockaddr_in *) &local_addr);
+	}
+
+	if (opt_max_retry)
+		failtime = time(NULL) + opt_max_retry;
+
+	while (hosts) {
+		struct pollfd	pfd;
+		time_t		now = time(NULL);
+		unsigned int	sent = 0;
+		struct nsm_host	*hp;
+		long		wait;
+
+		if (failtime && now >= failtime)
+			break;
+
+		while ((wait = hosts->send_next - now) <= 0) {
+			/* Never send more than 10 packets at once */
+			if (sent++ >= 10)
+				break;
+
+			/* Remove queue head */
+			hp = hosts;
+			hosts = hp->next;
+
+			notify_host(sock, hp);
+
+			/* Set the timeout for this call, using an
+			   exponential timeout strategy */
+			wait = hp->timeout;
+			if ((hp->timeout <<= 1) > NSM_MAX_TIMEOUT)
+				hp->timeout = NSM_MAX_TIMEOUT;
+			hp->send_next = now + wait;
+			hp->retries++;
+
+			insert_host(hp);
+		}
+
+		nsm_log(LOG_DEBUG, "Host %s due in %ld seconds",
+				hosts->name, wait);
+
+		pfd.fd = sock;
+		pfd.events = POLLIN;
+
+		wait *= 1000;
+		if (wait < 100)
+			wait = 100;
+		if (poll(&pfd, 1, wait) != 1)
+			continue;
+
+		recv_reply(sock);
+	}
+}
+
+/*
+ * Send notification to a single host
+ */
+void
+notify_host(int sock, struct nsm_host *host)
+{
+	static unsigned int	xid = 0;
+	nsm_address		dest;
+	uint32_t		msgbuf[MAXMSGSIZE], *p;
+	unsigned int		len;
+
+	if (!xid)
+		xid = getpid() + time(NULL);
+	if (!host->xid)
+		host->xid = xid++;
+
+	memset(msgbuf, 0, sizeof(msgbuf));
+	p = msgbuf;
+	*p++ = htonl(host->xid);
+	*p++ = 0;
+	*p++ = htonl(2);
+
+	/* If we retransmitted 4 times, reset the port to force
+	 * a new portmap lookup (in case statd was restarted)
+	 */
+	if (host->retries >= 4) {
+		addr_set_port(&host->addr, 0);
+		host->retries = 0;
+	}
+
+	dest = host->addr;
+	if (addr_get_port(&dest) == 0) {
+		/* Build a PMAP packet */
+		nsm_log(LOG_DEBUG, "Sending portmap query to %s", host->name);
+
+		addr_set_port(&dest, 111);
+		*p++ = htonl(100000);
+		*p++ = htonl(2);
+		*p++ = htonl(3);
+
+		/* Auth and verf */
+		*p++ = 0; *p++ = 0;
+		*p++ = 0; *p++ = 0;
+
+		*p++ = htonl(NSM_PROGRAM);
+		*p++ = htonl(NSM_VERSION);
+		*p++ = htonl(IPPROTO_UDP);
+		*p++ = 0;
+	} else {
+		/* Build an SM_NOTIFY packet */
+		nsm_log(LOG_DEBUG, "Sending SM_NOTIFY to %s", host->name);
+
+		*p++ = htonl(NSM_PROGRAM);
+		*p++ = htonl(NSM_VERSION);
+		*p++ = htonl(NSM_NOTIFY);
+
+		/* Auth and verf */
+		*p++ = 0; *p++ = 0;
+		*p++ = 0; *p++ = 0;
+
+		/* state change */
+		len = strlen(nsm_hostname);
+		*p++ = htonl(len);
+		memcpy(p, nsm_hostname, len);
+		p += (len + 3) >> 2;
+		*p++ = htonl(nsm_state);
+	}
+	len = (p - msgbuf) << 2;
+
+	sendto(sock, msgbuf, len, 0, (struct sockaddr *) &dest, sizeof(dest));
+}
+
+/*
+ * Receive reply from remote host
+ */
+void
+recv_reply(int sock)
+{
+	struct nsm_host	*hp;
+	uint32_t	msgbuf[MAXMSGSIZE], *p, *end;
+	uint32_t	xid;
+	int		res;
+
+	res = recv(sock, msgbuf, sizeof(msgbuf), 0);
+	if (res < 0)
+		return;
+
+	nsm_log(LOG_DEBUG, "Received packet...");
+
+	p = msgbuf;
+	end = p + (res >> 2);
+
+	xid = ntohl(*p++);
+	if (*p++ != htonl(1)	/* must be REPLY */
+	 || *p++ != htonl(0)	/* must be ACCEPTED */
+	 || *p++ != htonl(0)	/* must be NULL verifier */
+	 || *p++ != htonl(0)
+	 || *p++ != htonl(0))	/* must be SUCCESS */
+		return;
+
+	/* Before we look at the data, find the host struct for
+	   this reply */
+	if ((hp = find_host(xid)) == NULL)
+		return;
+
+	if (addr_get_port(&hp->addr) == 0) {
+		/* This was a portmap request */
+		unsigned int	port;
+
+		port = ntohl(*p++);
+		if (p > end)
+			goto fail;
+
+		hp->send_next = time(NULL);
+		if (port == 0) {
+			/* No binding for statd. Delay the next
+			 * portmap query for max timeout */
+			nsm_log(LOG_DEBUG, "No statd on %s", hp->name);
+			hp->timeout = NSM_MAX_TIMEOUT;
+			hp->send_next += NSM_MAX_TIMEOUT;
+		} else {
+			addr_set_port(&hp->addr, port);
+			if (hp->timeout >= NSM_MAX_TIMEOUT / 4)
+				hp->timeout = NSM_MAX_TIMEOUT / 4;
+		}
+		hp->xid = 0;
+	} else {
+		/* Successful NOTIFY call. Server returns void,
+		 * so nothing we need to do here (except
+		 * check that we didn't read past the end of the
+		 * packet)
+		 */
+		if (p <= end) {
+			nsm_log(LOG_DEBUG, "Host %s notified successfully", hp->name);
+			unlink(hp->path);
+			free(hp->name);
+			free(hp->path);
+			free(hp);
+			return;
+		}
+	}
+
+fail:	/* Re-insert the host */
+	insert_host(hp);
+}
+
+/*
+ * Back up all hosts from the sm directory to sm.bak
+ */
+static void
+backup_hosts(const char *dirname, const char *bakname)
+{
+	struct dirent	*de;
+	DIR		*dir;
+
+	if (!(dir = opendir(dirname))) {
+		perror(dirname);
+		return;
+	}
+
+	while ((de = readdir(dir)) != NULL) {
+		char	src[1024], dst[1024];
+
+		if (de->d_name[0] == '.')
+			continue;
+
+		snprintf(src, sizeof(src), "%s/%s", dirname, de->d_name);
+		snprintf(dst, sizeof(dst), "%s/%s", bakname, de->d_name);
+		if (rename(src, dst) < 0) {
+			nsm_log(LOG_WARNING,
+				"Failed to rename %s -> %s: %m",
+				src, dst);
+		}
+	}
+	closedir(dir);
+}
+
+/*
+ * Get all entries from sm.bak and convert them to host names
+ */
+static void
+get_hosts(const char *dirname)
+{
+	struct nsm_host	*host;
+	struct dirent	*de;
+	DIR		*dir;
+
+	if (!(dir = opendir(dirname))) {
+		perror(dirname);
+		return;
+	}
+
+	host = NULL;
+	while ((de = readdir(dir)) != NULL) {
+		struct stat	stb;
+		char		path[1024];
+
+		if (de->d_name[0] == '.')
+			continue;
+		if (host == NULL)
+			host = calloc(1, sizeof(*host));
+
+		snprintf(path, sizeof(path), "%s/%s", dirname, de->d_name);
+		if (!addr_parse(AF_INET, de->d_name, &host->addr)
+		 && !addr_parse(AF_INET6, de->d_name, &host->addr)
+		 && !host_lookup(AF_INET, de->d_name, &host->addr)) {
+			nsm_log(LOG_WARNING,
+				"%s doesn't seem to be a valid address, skipped",
+				de->d_name);
+			unlink(path);
+			continue;
+		}
+
+		if (stat(path, &stb) < 0)
+			continue;
+		host->last_used = stb.st_mtime;
+		host->timeout = NSM_TIMEOUT;
+		host->path = strdup(path);
+		host->name = strdup(de->d_name);
+
+		insert_host(host);
+		host = NULL;
+	}
+	closedir(dir);
+
+	if (host)
+		free(host);
+}
+
+/*
+ * Insert host into sorted list
+ */
+void
+insert_host(struct nsm_host *host)
+{
+	struct nsm_host	**where, *p;
+
+	where = &hosts;
+	while ((p = *where) != 0) {
+		/* Sort in ascending order of timeout */
+		if (host->send_next < p->send_next)
+			break;
+		/* If we have the same timeout, put the
+		 * most recently used host first.
+		 * This makes sure that "recent" hosts
+		 * get notified first.
+		 */
+		if (host->send_next == p->send_next
+		 && host->last_used > p->last_used)
+			break;
+		where = &p->next;
+	}
+
+	host->next = *where;
+	*where = host;
+}
+
+/*
+ * Find host given the XID
+ */
+struct nsm_host *
+find_host(uint32_t xid)
+{
+	struct nsm_host	**where, *p;
+
+	where = &hosts;
+	while ((p = *where) != 0) {
+		if (p->xid == xid) {
+			*where = p->next;
+			return p;
+		}
+		where = &p->next;
+	}
+	return NULL;
+}
+
+
+/*
+ * Retrieve the current NSM state
+ */
+unsigned int
+nsm_get_state(int update)
+{
+	char		newfile[PATH_MAX];
+	int		fd, state;
+
+	if ((fd = open(_SM_STATE_PATH, O_RDONLY)) < 0) {
+		if (!opt_quiet) {
+			nsm_log(LOG_WARNING, "%s: %m", _SM_STATE_PATH);
+			nsm_log(LOG_WARNING, "Creating %s, set initial state 1",
+				_SM_STATE_PATH);
+		}
+		state = 1;
+		update = 1;
+	} else {
+		if (read(fd, &state, sizeof(state)) != sizeof(state)) {
+			nsm_log(LOG_WARNING,
+				"%s: bad file size, setting state = 1",
+				_SM_STATE_PATH);
+			state = 1;
+			update = 1;
+		} else {
+			if (!(state & 1))
+				state += 1;
+		}
+		close(fd);
+	}
+
+	if (update) {
+		state += 2;
+		snprintf(newfile, sizeof(newfile),
+				"%s.new", _SM_STATE_PATH);
+		if ((fd = open(newfile, O_CREAT|O_WRONLY, 0644)) < 0) {
+			nsm_log(LOG_WARNING, "Cannot create %s: %m", newfile);
+			exit(1);
+		}
+		if (write(fd, &state, sizeof(state)) != sizeof(state)) {
+			nsm_log(LOG_WARNING,
+				"Failed to write state to %s", newfile);
+			exit(1);
+		}
+		close(fd);
+		if (rename(newfile, _SM_STATE_PATH) < 0) {
+			nsm_log(LOG_WARNING,
+				"Cannot create %s: %m", _SM_STATE_PATH);
+			exit(1);
+		}
+		sync();
+	}
+
+	return state;
+}
+
+/*
+ * Address handling utilities
+ */
+static int
+addr_parse(int af, const char *name, nsm_address *addr)
+{
+	void	*ptr;
+
+	if (af == AF_INET)
+		ptr = &((struct sockaddr_in *) addr)->sin_addr;
+	else if (af == AF_INET6)
+		ptr = &((struct sockaddr_in6 *) addr)->sin6_addr;
+	else
+		return 0;
+	if (inet_pton(af, name, ptr) <= 0)
+		return 0;
+	((struct sockaddr *) addr)->sa_family = af;
+	return 1;
+}
+
+int
+addr_get_port(nsm_address *addr)
+{
+	switch (((struct sockaddr *) addr)->sa_family) {
+	case AF_INET:
+		return ntohs(((struct sockaddr_in *) addr)->sin_port);
+	case AF_INET6:
+		return ntohs(((struct sockaddr_in6 *) addr)->sin6_port);
+	}
+	return 0;
+}
+
+static void
+addr_set_port(nsm_address *addr, int port)
+{
+	switch (((struct sockaddr *) addr)->sa_family) {
+	case AF_INET:
+		((struct sockaddr_in *) addr)->sin_port = htons(port);
+		break;
+	case AF_INET6:
+		((struct sockaddr_in6 *) addr)->sin6_port = htons(port);
+	}
+}
+
+static int
+host_lookup(int af, const char *name, nsm_address *addr)
+{
+	struct addrinfo	hints, *ai;
+	int okay = 0;
+
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_family = af;
+
+	if (getaddrinfo(name, NULL, &hints, &ai) != 0)
+		return 0;
+
+	if (ai->ai_addrlen < sizeof(*addr)) {
+		memcpy(addr, ai->ai_addr, ai->ai_addrlen);
+		okay = 1;
+	}
+
+	freeaddrinfo(ai);
+	return okay;
+}
+
+/*
+ * Log a message
+ */
+void
+nsm_log(int fac, const char *fmt, ...)
+{
+	va_list	ap;
+
+	if (fac == LOG_DEBUG && !opt_debug)
+		return;
+
+	va_start(ap, fmt);
+	if (log_syslog)
+		vsyslog(fac, fmt, ap);
+	else {
+		vfprintf(stderr, fmt, ap);
+		fputs("\n", stderr);
+	}
+	va_end(ap);
+}