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@

1 files changed, 407 insertions, 0 deletions

diff --git a/usr.sbin/snmpd/snmpd.h b/usr.sbin/snmpd/snmpd.h
new file mode 100644
index 00000000000..b8570b3ddaa
--- /dev/null
+++ b/usr.sbin/snmpd/snmpd.h
@@ -0,0 +1,407 @@
+/*	$OpenBSD: snmpd.h,v 1.1 2007/12/05 09:22:44 reyk Exp $	*/
+
+/*
+ * Copyright (c) 2007 Reyk Floeter <reyk@vantronix.net>
+ * 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.
+ */
+
+#ifndef _SNMPD_H
+#define _SNMPD_H
+
+#include <netinet/in.h>
+#include <netinet/if_ether.h>
+#include <net/route.h>
+
+#include <ber.h>
+#include <snmp.h>
+
+/*
+ * common definitions for snmpd
+ */
+
+#define CONF_FILE		"/etc/snmpd.conf"
+#define SNMPD_SOCKET		"/var/run/snmpd.sock"
+#define SNMPD_USER		"_snmpd"
+#define SNMPD_PORT		161
+#define SNMPD_TRAPPORT		162
+
+#define SNMPD_MAXSTRLEN		484
+#define SNMPD_MAXCOMMUNITYLEN	SNMPD_MAXSTRLEN
+#define SNMPD_MAXVARBINDLEN	1210
+
+#define SMALL_READ_BUF_SIZE	1024
+#define READ_BUF_SIZE		65535
+#define	RT_BUF_SIZE		16384
+#define	MAX_RTSOCK_BUF		(128 * 1024)
+
+struct address {
+	struct sockaddr_storage	 ss;
+	in_port_t		 port;
+	char			 ifname[IFNAMSIZ];
+	TAILQ_ENTRY(address)	 entry;
+};
+TAILQ_HEAD(addresslist, address);
+
+/*
+ * imsg framework and privsep
+ */
+
+struct buf {
+	TAILQ_ENTRY(buf)	 entry;
+	u_char			*buf;
+	size_t			 size;
+	size_t			 max;
+	size_t			 wpos;
+	size_t			 rpos;
+	int			 fd;
+};
+
+struct msgbuf {
+	TAILQ_HEAD(, buf)	 bufs;
+	u_int32_t		 queued;
+	int			 fd;
+};
+
+#define IMSG_HEADER_SIZE	sizeof(struct imsg_hdr)
+#define MAX_IMSGSIZE		8192
+
+struct buf_read {
+	u_char			 buf[READ_BUF_SIZE];
+	u_char			*rptr;
+	size_t			 wpos;
+};
+
+struct imsg_fd {
+	TAILQ_ENTRY(imsg_fd)	entry;
+	int			fd;
+};
+
+struct imsgbuf {
+	TAILQ_HEAD(, imsg_fd)	 fds;
+	struct buf_read		 r;
+	struct msgbuf		 w;
+	struct event		 ev;
+	void			(*handler)(int, short, void *);
+	int			 fd;
+	pid_t			 pid;
+	short			 events;
+};
+
+enum imsg_type {
+	IMSG_NONE,
+	IMSG_CTL_OK,		/* answer to snmpctl requests */
+	IMSG_CTL_FAIL,
+	IMSG_CTL_END,
+	IMSG_CTL_NOTIFY
+};
+
+struct imsg_hdr {
+	u_int16_t	 type;
+	u_int16_t	 len;
+	u_int32_t	 peerid;
+	pid_t		 pid;
+};
+
+struct imsg {
+	struct imsg_hdr	 hdr;
+	void		*data;
+};
+
+enum {
+	PROC_PARENT,	/* Parent process and application interface */
+	PROC_SNMPE	/* SNMP engine */
+} snmpd_process;
+
+/* initially control.h */
+struct {
+	struct event	 ev;
+	int		 fd;
+} control_state;
+
+enum blockmodes {
+	BM_NORMAL,
+	BM_NONBLOCK
+};
+
+struct ctl_conn {
+	TAILQ_ENTRY(ctl_conn)	 entry;
+	u_int8_t		 flags;
+#define CTL_CONN_NOTIFY		 0x01
+	struct imsgbuf		 ibuf;
+
+};
+TAILQ_HEAD(ctl_connlist, ctl_conn);
+extern  struct ctl_connlist ctl_conns;
+
+/*
+ * kroute
+ */
+
+struct kroute {
+	struct in_addr	prefix;
+	struct in_addr	nexthop;
+	u_int16_t	flags;
+	u_int16_t	rtlabel;
+	u_short		if_index;
+	u_int8_t	prefixlen;
+	u_long		ticks;
+};
+
+struct kif_addr {
+	TAILQ_ENTRY(kif_addr)	 entry;
+	struct in_addr		 addr;
+	struct in_addr		 mask;
+	struct in_addr		 dstbrd;
+};
+
+struct kif {
+	char			 if_name[IF_NAMESIZE];
+	char			 if_descr[IFDESCRSIZE];
+	u_int8_t		 if_lladdr[ETHER_ADDR_LEN];
+	int			 if_flags;
+	u_short			 if_index;
+	u_int8_t		 if_nhreachable; /* for nexthop verification */
+	u_long			 if_ticks;
+	struct if_data		 if_data;
+};
+
+#define	F_OSPFD_INSERTED	0x0001
+#define	F_KERNEL		0x0002
+#define	F_BGPD_INSERTED		0x0004
+#define	F_CONNECTED		0x0008
+#define	F_DOWN			0x0010
+#define	F_STATIC		0x0020
+#define	F_DYNAMIC		0x0040
+#define	F_REDISTRIBUTED		0x0100
+
+/*
+ * Message Processing Subsystem (mps)
+ */
+
+struct oid {
+	struct ber_oid		 o_id;
+#define o_oid			 o_id.bo_id
+#define o_oidlen		 o_id.bo_n
+
+	char			*o_name;
+
+	u_int			 o_flags;
+
+	int			(*o_get)(struct oid *, struct ber_oid *,
+				    struct ber_element **);
+	int			(*o_set)(struct oid *, struct ber_oid *,
+				    struct ber_element **);
+
+	void			*o_data;
+	long long		 o_val;
+
+	RB_ENTRY(oid)		 o_element;
+};
+
+#define OID_ROOT		0x00
+#define OID_RD			0x01
+#define OID_WR			0x02
+#define OID_IFSET		0x04	/* only if user-specified value */
+#define OID_DYNAMIC		0x08	/* free allocated data */
+#define OID_TABLE		0x10	/* dynamic sub-elements */
+#define OID_MIB			0x20	/* root-OID of a supported MIB */
+
+#define OID_RS			(OID_RD|OID_IFSET)
+#define OID_WS			(OID_WR|OID_IFSET)
+#define OID_RW			(OID_RD|OID_WR)
+#define OID_RWS			(OID_RW|OID_IFSET)
+
+#define OID_TRD			(OID_RD|OID_TABLE)
+#define OID_TWR			(OID_WR|OID_TABLE)
+#define OID_TRS			(OID_RD|OID_IFSET|OID_TABLE)
+#define OID_TWS			(OID_WR|OID_IFSET|OID_TABLE)
+#define OID_TRW			(OID_RD|OID_WR|OID_TABLE)
+#define OID_TRWS		(OID_RW|OID_IFSET|OID_TABLE)
+
+#define OID_NOTSET(_oid)						\
+	(((_oid)->o_flags & OID_IFSET) &&				\
+	((_oid)->o_data == NULL) && ((_oid)->o_val == 0))
+
+#define OID(_mib...)		{ { _mib } }
+#define MIB(_mib...)		{ { MIB_##_mib } }
+
+/*
+ * daemon structures
+ */
+
+struct snmp_message {
+	u_int8_t		 sm_version;
+	char			 sm_community[SNMPD_MAXCOMMUNITYLEN];
+	u_int			 sm_context;
+
+	struct ber_element	*sm_header;
+	struct ber_element	*sm_headerend;
+
+	long long		 sm_request;
+
+	long long		 sm_error;
+#define sm_nonrepeaters		 sm_error
+	long long		 sm_errorindex;
+#define sm_maxrepetitions	 sm_errorindex
+
+	struct ber_element	*sm_pdu;
+	struct ber_element	*sm_pduend;
+
+	struct ber_element	*sm_varbind;
+	struct ber_element	*sm_varbindresp;
+};
+
+/* Defined in SNMPv2-MIB.txt (RFC 3418) */
+struct snmp_stats {
+	u_int32_t		snmp_inpkts;
+	u_int32_t		snmp_outpkts;
+	u_int32_t		snmp_inbadversions;
+	u_int32_t		snmp_inbadcommunitynames;
+	u_int32_t		snmp_inbadcommunityuses;
+	u_int32_t		snmp_inasnparseerrs;
+	u_int32_t		snmp_intoobigs;
+	u_int32_t		snmp_innosuchnames;
+	u_int32_t		snmp_inbadvalues;
+	u_int32_t		snmp_inreadonlys;
+	u_int32_t		snmp_ingenerrs;
+	u_int32_t		snmp_intotalreqvars;
+	u_int32_t		snmp_intotalsetvars;
+	u_int32_t		snmp_ingetrequests;
+	u_int32_t		snmp_ingetnexts;
+	u_int32_t		snmp_insetrequests;
+	u_int32_t		snmp_ingetresponses;
+	u_int32_t		snmp_intraps;
+	u_int32_t		snmp_outtoobigs;
+	u_int32_t		snmp_outnosuchnames;
+	u_int32_t		snmp_outbadvalues;
+	u_int32_t		snmp_outgenerrs;
+	u_int32_t		snmp_outgetrequests;
+	u_int32_t		snmp_outgetnexts;
+	u_int32_t		snmp_outsetrequests;
+	u_int32_t		snmp_outgetresponses;
+	u_int32_t		snmp_outtraps;
+	int			snmp_enableauthentraps;
+	u_int32_t		snmp_silentdrops;
+	u_int32_t		snmp_proxydrops;
+};
+
+struct snmpd {
+	u_int8_t		 sc_flags;
+#define SNMPD_F_VERBOSE		 0x01
+#define SNMPD_F_NONAMES		 0x02
+
+	const char		*sc_confpath;
+	struct address		 sc_address;
+	int			 sc_sock;
+	struct event		 sc_ev;
+	struct timeval		 sc_starttime;
+
+	char			 sc_rdcommunity[SNMPD_MAXCOMMUNITYLEN];
+	char			 sc_rwcommunity[SNMPD_MAXCOMMUNITYLEN];
+	char			 sc_trcommunity[SNMPD_MAXCOMMUNITYLEN];
+
+	struct snmp_stats	 sc_stats;
+};
+
+/* control.c */
+int		 control_init(void);
+int		 control_listen(struct snmpd *, struct imsgbuf *);
+void		 control_accept(int, short, void *);
+void		 control_dispatch_imsg(int, short, void *);
+void		 control_imsg_forward(struct imsg *);
+void		 control_cleanup(void);
+
+void		 session_socket_blockmode(int, enum blockmodes);
+
+/* parse.y */
+struct snmpd	*parse_config(const char *, u_int);
+int		 cmdline_symset(char *);
+
+/* log.c */
+void		 log_init(int);
+void		 log_warn(const char *, ...);
+void		 log_warnx(const char *, ...);
+void		 log_info(const char *, ...);
+void		 log_debug(const char *, ...);
+__dead void	 fatal(const char *);
+__dead void	 fatalx(const char *);
+const char	*log_host(struct sockaddr_storage *, char *, size_t);
+
+/* buffer.c */
+struct buf	*buf_open(size_t);
+struct buf	*buf_dynamic(size_t, size_t);
+int		 buf_add(struct buf *, void *, size_t);
+void		*buf_reserve(struct buf *, size_t);
+int		 buf_close(struct msgbuf *, struct buf *);
+void		 buf_free(struct buf *);
+void		 msgbuf_init(struct msgbuf *);
+void		 msgbuf_clear(struct msgbuf *);
+int		 msgbuf_write(struct msgbuf *);
+
+/* imsg.c */
+void		 imsg_init(struct imsgbuf *, int, void (*)(int, short, void *));
+ssize_t		 imsg_read(struct imsgbuf *);
+ssize_t		 imsg_get(struct imsgbuf *, struct imsg *);
+int		 imsg_compose(struct imsgbuf *, enum imsg_type, u_int32_t,
+		    pid_t, int, void *, u_int16_t);
+struct buf	*imsg_create(struct imsgbuf *, enum imsg_type, u_int32_t,
+		    pid_t, u_int16_t);
+int		 imsg_add(struct buf *, void *, u_int16_t);
+int		 imsg_close(struct imsgbuf *, struct buf *);
+void		 imsg_free(struct imsg *);
+void		 imsg_event_add(struct imsgbuf *); /* provided externally */
+int		 imsg_get_fd(struct imsgbuf *);
+
+/* kroute.c */
+int		 kr_init(void);
+void		 kr_shutdown(void);
+
+int		 kr_updateif(u_int);
+u_int		 kr_ifnumber(void);
+u_long		 kr_iflastchange(void);
+struct kif	*kr_getif(u_short);
+struct kif	*kr_getnextif(u_short);
+
+/* snmpe.c */
+pid_t		 snmpe(struct snmpd *, int [2]);
+
+/* mps.c */
+int		 mps_init(void);
+u_long		 mps_getticks(void);
+long		 mps_oid_cmp(struct oid *, struct oid *);
+void		 mps_mibtree(struct oid *, size_t);
+struct oid	*mps_foreach(struct oid *, u_int);
+void		 mps_oidlen(struct ber_oid *);
+char		*mps_oidstring(struct ber_oid *, char *, size_t);
+struct ber_element *
+		 mps_getreq(struct ber_element *, struct ber_oid *);
+struct ber_element *
+		 mps_getnextreq(struct ber_element *, struct ber_oid *);
+int		 mps_setreq(struct ber_element *, struct ber_oid *);
+int		 mps_set(struct ber_oid *, void *, long long);
+void		 mps_delete(struct oid *);
+void		 mps_insert(struct oid *);
+int		 mps_getstr(struct oid *, struct ber_oid *,
+		    struct ber_element **);
+int		 mps_setstr(struct oid *, struct ber_oid *,
+		    struct ber_element **);
+int		 mps_getint(struct oid *, struct ber_oid *,
+		    struct ber_element **);
+int		 mps_setint(struct oid *, struct ber_oid *,
+		    struct ber_element **);
+int		 mps_getts(struct oid *, struct ber_oid *,
+		    struct ber_element **);
+
+#endif /* _SNMPD_H */