Start working on snmpd(8) and snmpctl(8), a lightweight SNMP implementation

for OpenBSD.  SNMP is a necessary evil.  This is work in progress, don't
expect too much from it yet.

ok deraadt@

5 files changed, 448 insertions, 0 deletions

diff --git a/usr.sbin/snmpctl/Makefile b/usr.sbin/snmpctl/Makefile
new file mode 100644
index 00000000000..dedb04dd6e7
--- /dev/null
+++ b/usr.sbin/snmpctl/Makefile
@@ -0,0 +1,16 @@
+#	$Id: Makefile,v 1.1 2007/12/05 09:22:44 reyk Exp $
+
+.PATH:		${.CURDIR}/../snmpd
+
+PROG=		snmpctl
+SRCS=		buffer.c imsg.c log.c snmpctl.c parser.c
+
+MAN=		snmpctl.8
+
+CFLAGS+=	-Wall -I${.CURDIR} -I${.CURDIR}/../snmpd
+CFLAGS+=	-Wstrict-prototypes -Wmissing-prototypes
+CFLAGS+=	-Wmissing-declarations
+CFLAGS+=	-Wshadow -Wpointer-arith -Wcast-qual
+CFLAGS+=	-Wsign-compare -Wbounded
+
+.include <bsd.prog.mk>
diff --git a/usr.sbin/snmpctl/parser.c b/usr.sbin/snmpctl/parser.c
new file mode 100644
index 00000000000..1f9c0140c6e
--- /dev/null
+++ b/usr.sbin/snmpctl/parser.c
@@ -0,0 +1,155 @@
+/*	$Id: parser.c,v 1.1 2007/12/05 09:22:44 reyk Exp $	*/
+
+/*
+ * Copyright (c) 2004 Esben Norby <norby@openbsd.org>
+ * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/queue.h>
+#include <sys/tree.h>
+
+#include <netinet/in.h>
+#include <net/if.h>
+#include <arpa/inet.h>
+
+#include <err.h>
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <event.h>
+
+#include "snmpd.h"
+#include "parser.h"
+
+enum token_type {
+	NOTOKEN,
+	ENDTOKEN,
+	KEYWORD
+};
+
+struct token {
+	enum token_type		 type;
+	const char		*keyword;
+	int			 value;
+	const struct token	*next;
+};
+
+static const struct token t_main[];
+static const struct token t_show[];
+
+static const struct token t_main[] = {
+	{KEYWORD,	"monitor",	MONITOR,	NULL},
+	{ENDTOKEN,	"",		NONE,		NULL}
+};
+
+static struct parse_result	res;
+
+struct parse_result *
+parse(int argc, char *argv[])
+{
+	const struct token	*table = t_main;
+	const struct token	*match;
+
+	bzero(&res, sizeof(res));
+
+	while (argc >= 0) {
+		if ((match = match_token(argv[0], table)) == NULL) {
+			fprintf(stderr, "valid commands/args:\n");
+			show_valid_args(table);
+			return (NULL);
+		}
+
+		argc--;
+		argv++;
+
+		if (match->type == NOTOKEN || match->next == NULL)
+			break;
+
+		table = match->next;
+	}
+
+	if (argc > 0) {
+		fprintf(stderr, "superfluous argument: %s\n", argv[0]);
+		return (NULL);
+	}
+
+	return (&res);
+}
+
+const struct token *
+match_token(const char *word, const struct token table[])
+{
+	u_int			 i, match;
+	const struct token	*t = NULL;
+
+	match = 0;
+
+	for (i = 0; table[i].type != ENDTOKEN; i++) {
+		switch (table[i].type) {
+		case NOTOKEN:
+			if (word == NULL || strlen(word) == 0) {
+				match++;
+				t = &table[i];
+			}
+			break;
+		case KEYWORD:
+			if (word != NULL && strncmp(word, table[i].keyword,
+			    strlen(word)) == 0) {
+				match++;
+				t = &table[i];
+				if (t->value)
+					res.action = t->value;
+			}
+			break;
+		case ENDTOKEN:
+			break;
+		}
+	}
+
+	if (match != 1) {
+		if (word == NULL)
+			fprintf(stderr, "missing argument:\n");
+		else if (match > 1)
+			fprintf(stderr, "ambiguous argument: %s\n", word);
+		else if (match < 1)
+			fprintf(stderr, "unknown argument: %s\n", word);
+		return (NULL);
+	}
+
+	return (t);
+}
+
+void
+show_valid_args(const struct token table[])
+{
+	int	i;
+
+	for (i = 0; table[i].type != ENDTOKEN; i++) {
+		switch (table[i].type) {
+		case NOTOKEN:
+			fprintf(stderr, "  <cr>\n");
+			break;
+		case KEYWORD:
+			fprintf(stderr, "  %s\n", table[i].keyword);
+			break;
+		case ENDTOKEN:
+			break;
+		}
+	}
+}
diff --git a/usr.sbin/snmpctl/parser.h b/usr.sbin/snmpctl/parser.h
new file mode 100644
index 00000000000..41202685b9d
--- /dev/null
+++ b/usr.sbin/snmpctl/parser.h
@@ -0,0 +1,30 @@
+/*	$OpenBSD: parser.h,v 1.1 2007/12/05 09:22:44 reyk Exp $	*/
+
+/*
+ * Copyright (c) 2007 Reyk Floeter <reyk@vantronix.net>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+enum actions {
+	NONE,
+	MONITOR
+};
+
+struct parse_result {
+	enum actions	action;
+};
+
+struct parse_result	*parse(int, char *[]);
+const struct token      *match_token(const char *, const struct token []);
+void                     show_valid_args(const struct token []);
diff --git a/usr.sbin/snmpctl/snmpctl.8 b/usr.sbin/snmpctl/snmpctl.8
new file mode 100644
index 00000000000..c83747ffe1c
--- /dev/null
+++ b/usr.sbin/snmpctl/snmpctl.8
@@ -0,0 +1,56 @@
+.\" $OpenBSD: snmpctl.8,v 1.1 2007/12/05 09:22:44 reyk Exp $
+.\"
+.\" Copyright (c) 2006 Reyk Floeter <reyk@vantronix.net>
+.\"
+.\" Permission to use, copy, modify, and distribute this software for any
+.\" purpose with or without fee is hereby granted, provided that the above
+.\" copyright notice and this permission notice appear in all copies.
+.\"
+.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+.\"
+.Dd $Mdocdate: December 5 2007 $
+.Dt SNMPCTL 8
+.Os
+.Sh NAME
+.Nm snmpctl
+.Nd control the SNMP daemon
+.Sh SYNOPSIS
+.Nm
+.Ar command
+.Op Ar arguments ...
+.Sh DESCRIPTION
+The
+.Nm
+program controls the
+.Xr snmpd 8
+daemon.
+.Pp
+The following commands are available:
+.Bl -tag -width Ds
+.It Cm something
+Do something
+.El
+.Sh FILES
+.Bl -tag -width "/var/run/snmpd.sockXX" -compact
+.It /var/run/snmpd.sock
+Unix-domain socket used for communication with
+.Xr snmpd 8 .
+.El
+.Sh SEE ALSO
+.Xr snmpd 8
+.Sh HISTORY
+The
+.Nm
+program first appeared in
+.Ox 4.3 .
+.Sh AUTHORS
+The
+.Nm
+program was written by
+.An Reyk Floeter Aq reyk@vantronix.net .
diff --git a/usr.sbin/snmpctl/snmpctl.c b/usr.sbin/snmpctl/snmpctl.c
new file mode 100644
index 00000000000..c625645223f
--- /dev/null
+++ b/usr.sbin/snmpctl/snmpctl.c
@@ -0,0 +1,191 @@
+/*	$Id: snmpctl.c,v 1.1 2007/12/05 09:22:44 reyk Exp $	*/
+
+/*
+ * Copyright (c) 2007 Reyk Floeter <reyk@vantronix.net>
+ * Copyright (c) 2005 Claudio Jeker <claudio@openbsd.org>
+ * Copyright (c) 2004, 2005 Esben Norby <norby@openbsd.org>
+ * Copyright (c) 2003 Henning Brauer <henning@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/queue.h>
+#include <sys/un.h>
+#include <sys/tree.h>
+
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <net/if.h>
+#include <net/if_media.h>
+#include <net/if_types.h>
+
+#include <err.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <event.h>
+
+#include "snmpd.h"
+#include "parser.h"
+
+__dead void	 usage(void);
+
+struct imsgname {
+	int type;
+	char *name;
+	void (*func)(struct imsg *);
+};
+
+struct imsgname *monitor_lookup(u_int8_t);
+void		 monitor_host_status(struct imsg *);
+void		 monitor_id(struct imsg *);
+int		 monitor(struct imsg *);
+
+struct imsgname imsgs[] = {
+	{ 0,				NULL,			NULL }
+};
+struct imsgname imsgunknown = {
+	-1,				"<unknown>",		NULL
+};
+
+struct imsgbuf	*ibuf;
+
+__dead void
+usage(void)
+{
+	extern char *__progname;
+
+	fprintf(stderr, "usage: %s <command> [arg [...]]\n", __progname);
+	exit(1);
+}
+
+/* dummy function so that hoststatectl does not need libevent */
+void
+imsg_event_add(struct imsgbuf *i)
+{
+	/* nothing */
+}
+
+int
+main(int argc, char *argv[])
+{
+	struct sockaddr_un	 sun;
+	struct parse_result	*res;
+	struct imsg		 imsg;
+	int			 ctl_sock;
+	int			 done = 0;
+	int			 n;
+
+	/* parse options */
+	if ((res = parse(argc - 1, argv + 1)) == NULL)
+		exit(1);
+
+	/* connect to snmpd control socket */
+	if ((ctl_sock = socket(AF_UNIX, SOCK_STREAM, 0)) == -1)
+		err(1, "socket");
+
+	bzero(&sun, sizeof(sun));
+	sun.sun_family = AF_UNIX;
+	strlcpy(sun.sun_path, SNMPD_SOCKET, sizeof(sun.sun_path));
+ reconnect:
+	if (connect(ctl_sock, (struct sockaddr *)&sun, sizeof(sun)) == -1) {
+		/* Keep retrying if running in monitor mode */
+		if (res->action == MONITOR &&
+		    (errno == ENOENT || errno == ECONNREFUSED)) {
+			usleep(100);
+			goto reconnect;
+		}
+		err(1, "connect: %s", SNMPD_SOCKET);
+	}
+
+	if ((ibuf = malloc(sizeof(struct imsgbuf))) == NULL)
+		err(1, NULL);
+	imsg_init(ibuf, ctl_sock, NULL);
+	done = 0;
+
+	/* process user request */
+	switch (res->action) {
+	case NONE:
+		usage();
+		/* not reached */
+	case MONITOR:
+		imsg_compose(ibuf, IMSG_CTL_NOTIFY, 0, 0, -1, NULL, 0);
+		break;
+	}
+
+	while (ibuf->w.queued)
+		if (msgbuf_write(&ibuf->w) < 0)
+			err(1, "write error");
+
+	while (!done) {
+		if ((n = imsg_read(ibuf)) == -1)
+			errx(1, "imsg_read error");
+		if (n == 0)
+			errx(1, "pipe closed");
+
+		while (!done) {
+			if ((n = imsg_get(ibuf, &imsg)) == -1)
+				errx(1, "imsg_get error");
+			if (n == 0)
+				break;
+			switch (res->action) {
+			case MONITOR:
+				done = monitor(&imsg);
+				break;
+			case NONE:
+				break;
+			}
+			imsg_free(&imsg);
+		}
+	}
+	close(ctl_sock);
+	free(ibuf);
+
+	return (0);
+}
+
+struct imsgname *
+monitor_lookup(u_int8_t type)
+{
+	int i;
+
+	for (i = 0; imsgs[i].name != NULL; i++)
+		if (imsgs[i].type == type)
+			return (&imsgs[i]);
+	return (&imsgunknown);
+}
+
+int
+monitor(struct imsg *imsg)
+{
+	time_t			 now;
+	int			 done = 0;
+	struct imsgname		*imn;
+
+	now = time(NULL);
+
+	imn = monitor_lookup(imsg->hdr.type);
+	printf("%s: imsg type %u len %u peerid %u pid %d\n", imn->name,
+	    imsg->hdr.type, imsg->hdr.len, imsg->hdr.peerid, imsg->hdr.pid);
+	printf("\ttimestamp: %u, %s", now, ctime(&now));
+	if (imn->type == -1)
+		done = 1;
+	if (imn->func != NULL)
+		(*imn->func)(imsg);
+
+	return (done);
+}