netlink: handle blocking read from netlink socket

[thirdparty/lldpd.git] / src / daemon / lldpd.h

/* -*- mode: c; c-file-style: "openbsd" -*- */
/*
 * Copyright (c) 2008 Vincent Bernat <bernat@luffy.cx>
 *
 * Permission to use, copy, modify, and/or 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 _LLDPD_H
#define _LLDPD_H

#if HAVE_CONFIG_H
#  include <config.h>
#endif

#ifdef HAVE_VALGRIND_VALGRIND_H
# include <valgrind/valgrind.h>
#else
# define RUNNING_ON_VALGRIND 0
#endif

#include <stdlib.h>
#include <stddef.h>
#include <string.h>
#include <sys/queue.h>
#include <sys/types.h>
#include <netinet/if_ether.h>
#include <netinet/in.h>
#include <sys/un.h>

#include "lldp-tlv.h"
#if defined (ENABLE_CDP) || defined (ENABLE_FDP)
#  include "protocols/cdp.h"
#endif
#ifdef ENABLE_SONMP
#  include "protocols/sonmp.h"
#endif
#ifdef ENABLE_EDP
#  include "protocols/edp.h"
#endif



#include "../compat/compat.h"
#include "../marshal.h"
#include "../log.h"
#include "../ctl.h"
#include "../lldpd-structs.h"

/* We don't want to import event2/event.h. We only need those as
   opaque structs. */
struct event;
struct event_base;

#define SYSFS_CLASS_NET "/sys/class/net/"
#define SYSFS_CLASS_DMI "/sys/class/dmi/id/"
#define LLDPD_TX_INTERVAL	30
#define LLDPD_TX_HOLD          4
#define LLDPD_TTL              LLDPD_TX_INTERVAL * LLDPD_TX_HOLD
#define LLDPD_TX_MSGDELAY	1
#define LLDPD_MAX_NEIGHBORS	32
#define LLDPD_FAST_TX_INTERVAL	1
#define LLDPD_FAST_INIT	4

#define USING_AGENTX_SUBAGENT_MODULE 1

#define PROTO_SEND_SIG struct lldpd *, struct lldpd_hardware *
#define PROTO_DECODE_SIG struct lldpd *, char *, int, struct lldpd_hardware *, struct lldpd_chassis **, struct lldpd_port **
#define PROTO_GUESS_SIG char *, int

#define ALIGNED_CAST(TYPE, ATTR) ((TYPE) (void *) (ATTR))

struct protocol {
	int		 mode;		/* > 0 mode identifier (unique per protocol) */
	int		 enabled;	/* Is this protocol enabled? */
	char		*name;		/* Name of protocol */
	char		 arg;		/* Argument to enable this protocol */
	int(*send)(PROTO_SEND_SIG);	/* How to send a frame */
	int(*decode)(PROTO_DECODE_SIG); /* How to decode a frame */
	int(*guess)(PROTO_GUESS_SIG);   /* Can be NULL, use MAC address in this case */
	u_int8_t	 mac1[ETHER_ADDR_LEN];  /* Destination MAC address used by this protocol */
	u_int8_t	 mac2[ETHER_ADDR_LEN];  /* Destination MAC address used by this protocol */
	u_int8_t	 mac3[ETHER_ADDR_LEN];  /* Destination MAC address used by this protocol */
};

#define SMART_HIDDEN(port) (port->p_hidden_in)

struct lldpd;

/* lldpd.c */
struct lldpd_hardware	*lldpd_get_hardware(struct lldpd *,
    char *, int);
struct lldpd_hardware	*lldpd_alloc_hardware(struct lldpd *, char *, int);
void	 lldpd_hardware_cleanup(struct lldpd*, struct lldpd_hardware *);
struct lldpd_mgmt *lldpd_alloc_mgmt(int family, void *addr, size_t addrsize, u_int32_t iface);
void	 lldpd_recv(struct lldpd *, struct lldpd_hardware *, int);
void	 lldpd_send(struct lldpd_hardware *);
void	 lldpd_loop(struct lldpd *);
int	 lldpd_main(int, char **, char **);
void	 lldpd_update_localports(struct lldpd *);
void	 lldpd_update_localchassis(struct lldpd *);
void	 lldpd_cleanup(struct lldpd *);

/* frame.c */
u_int16_t frame_checksum(const u_int8_t *, int, int);

/* event.c */
void	 levent_loop(struct lldpd *);
void	 levent_shutdown(struct lldpd *);
void	 levent_hardware_init(struct lldpd_hardware *);
void	 levent_hardware_add_fd(struct lldpd_hardware *, int);
void	 levent_hardware_release(struct lldpd_hardware *);
void	 levent_ctl_notify(char *, int, struct lldpd_port *);
void	 levent_send_now(struct lldpd *);
void	 levent_update_now(struct lldpd *);
int	 levent_iface_subscribe(struct lldpd *, int);
void	 levent_schedule_pdu(struct lldpd_hardware *);
void	 levent_schedule_cleanup(struct lldpd *);
int	 levent_make_socket_nonblocking(int);
int	 levent_make_socket_blocking(int);
#ifdef HOST_OS_LINUX
void	 levent_recv_error(int, const char*);
#endif

/* lldp.c */
int	 lldp_send_shutdown(PROTO_SEND_SIG);
int	 lldp_send(PROTO_SEND_SIG);
int	 lldp_decode(PROTO_DECODE_SIG);

/* cdp.c */
#ifdef ENABLE_CDP
int	 cdpv1_send(PROTO_SEND_SIG);
int	 cdpv2_send(PROTO_SEND_SIG);
int	 cdpv1_guess(PROTO_GUESS_SIG);
int	 cdpv2_guess(PROTO_GUESS_SIG);
#endif
#if defined (ENABLE_CDP) || defined (ENABLE_FDP)
int	 cdp_decode(PROTO_DECODE_SIG);
#endif
#ifdef ENABLE_FDP
int	 fdp_send(PROTO_SEND_SIG);
#endif

#ifdef ENABLE_SONMP
/* sonmp.c */
int	 sonmp_send(PROTO_SEND_SIG);
int	 sonmp_decode(PROTO_DECODE_SIG);
#endif

#ifdef ENABLE_EDP
/* edp.c */
int	 edp_send(PROTO_SEND_SIG);
int	 edp_decode(PROTO_DECODE_SIG);
#endif

/* dmi.c */
#ifdef ENABLE_LLDPMED
char	*dmi_hw(void);
char	*dmi_fw(void);
char	*dmi_sn(void);
char	*dmi_manuf(void);
char	*dmi_model(void);
char	*dmi_asset(void);
#endif

#ifdef USE_SNMP
/* agent.c */
void		 agent_shutdown(void);
void		 agent_init(struct lldpd *, const char *);
void		 agent_notify(struct lldpd_hardware *, int, struct lldpd_port *);
#endif

#ifdef ENABLE_PRIVSEP
/* agent_priv.c */
void		 agent_priv_register_domain(void);
#endif

/* client.c */
int
client_handle_client(struct lldpd *cfg,
    ssize_t(*send)(void *, int, void *, size_t),
    void *,
    enum hmsg_type type, void *buffer, size_t n,
    int*);

/* priv.c */
void	 priv_init(const char*, int, uid_t, gid_t);
void	 priv_wait(void);
void	 priv_ctl_cleanup(const char *ctlname);
char   	*priv_gethostname(void);
#ifdef HOST_OS_LINUX
int    	 priv_open(char*);
void	 asroot_open(void);
#endif
int    	 priv_iface_init(int, char *);
int	 asroot_iface_init_os(int, char *, int *);
int	 priv_iface_multicast(const char *, const u_int8_t *, int);
int	 priv_iface_description(const char *, const char *);
int	 asroot_iface_description_os(const char *, const char *);
int	 priv_iface_promisc(const char*);
int	 asroot_iface_promisc_os(const char *);
int	 priv_snmp_socket(struct sockaddr_un *);

enum priv_cmd {
	PRIV_PING,
	PRIV_DELETE_CTL_SOCKET,
	PRIV_GET_HOSTNAME,
	PRIV_OPEN,
	PRIV_IFACE_INIT,
	PRIV_IFACE_MULTICAST,
	PRIV_IFACE_DESCRIPTION,
	PRIV_IFACE_PROMISC,
	PRIV_SNMP_SOCKET,
};

/* priv-seccomp.c */
#if defined USE_SECCOMP && defined ENABLE_PRIVSEP
int priv_seccomp_init(int, int);
#endif

/* privsep_io.c */
enum priv_context {
	PRIV_PRIVILEGED,
	PRIV_UNPRIVILEGED
};
int	 may_read(enum priv_context, void *, size_t);
void	 must_read(enum priv_context, void *, size_t);
void	 must_write(enum priv_context, const void *, size_t);
void	 priv_privileged_fd(int);
void	 priv_unprivileged_fd(int);
int	 priv_fd(enum priv_context);
int	 receive_fd(enum priv_context);
void	 send_fd(enum priv_context, int);

/* interfaces-*.c */

/* BPF filter to get revelant information from interfaces */
/* LLDP: "ether proto 0x88cc and ether dst 01:80:c2:00:00:0e" */
/* FDP: "ether dst 01:e0:52:cc:cc:cc" */
/* CDP: "ether dst 01:00:0c:cc:cc:cc" */
/* SONMP: "ether dst 01:00:81:00:01:00" */
/* EDP: "ether dst 00:e0:2b:00:00:00" */
/* For optimization purpose, we first check if the first bit of the
   first byte is 1. if not, this can only be an EDP packet:

   tcpdump -dd "(ether[0] & 1 = 1 and
                 ((ether proto 0x88cc and (ether dst 01:80:c2:00:00:0e or
                                           ether dst 01:80:c2:00:00:03 or
                                           ether dst 01:80:c2:00:00:00)) or
                  (ether dst 01:e0:52:cc:cc:cc) or
                  (ether dst 01:00:0c:cc:cc:cc) or
                  (ether dst 01:00:81:00:01:00))) or
                (ether dst 00:e0:2b:00:00:00)"
*/

#define LLDPD_FILTER_F				\
	{ 0x30, 0, 0, 0x00000000 },		\
	{ 0x54, 0, 0, 0x00000001 },		\
	{ 0x15, 0, 16, 0x00000001 },		\
	{ 0x28, 0, 0, 0x0000000c },		\
	{ 0x15, 0, 6, 0x000088cc },		\
	{ 0x20, 0, 0, 0x00000002 },		\
	{ 0x15, 2, 0, 0xc200000e },		\
	{ 0x15, 1, 0, 0xc2000003 },		\
	{ 0x15, 0, 2, 0xc2000000 },		\
	{ 0x28, 0, 0, 0x00000000 },		\
	{ 0x15, 12, 13, 0x00000180 },		\
	{ 0x20, 0, 0, 0x00000002 },		\
	{ 0x15, 0, 2, 0x52cccccc },		\
	{ 0x28, 0, 0, 0x00000000 },		\
	{ 0x15, 8, 9, 0x000001e0 },		\
	{ 0x15, 1, 0, 0x0ccccccc },		\
	{ 0x15, 0, 2, 0x81000100 },		\
	{ 0x28, 0, 0, 0x00000000 },		\
	{ 0x15, 4, 5, 0x00000100 },		\
	{ 0x20, 0, 0, 0x00000002 },		\
	{ 0x15, 0, 3, 0x2b000000 },		\
	{ 0x28, 0, 0, 0x00000000 },		\
	{ 0x15, 0, 1, 0x000000e0 },		\
	{ 0x6, 0, 0, 0x00040000 },		\
	{ 0x6, 0, 0, 0x00000000 }

/* This function is responsible to refresh information about interfaces. It is
 * OS specific but should be present for each OS. It can use the functions in
 * `interfaces.c` as helper by providing a list of OS-independent interface
 * devices. */
void     interfaces_update(struct lldpd *);

/* interfaces.c */
/* An interface cannot be both physical and (bridge or bond or vlan) */
#define IFACE_PHYSICAL_T (1 << 0) /* Physical interface */
#define IFACE_BRIDGE_T   (1 << 1) /* Bridge interface */
#define IFACE_BOND_T     (1 << 2) /* Bond interface */
#define IFACE_VLAN_T     (1 << 3) /* VLAN interface */
#define IFACE_WIRELESS_T (1 << 4) /* Wireless interface */
struct interfaces_device {
	TAILQ_ENTRY(interfaces_device) next;
	int   ignore;		/* Ignore this interface */
	int   index;		/* Index */
	char *name;		/* Name */
	char *alias;		/* Alias */
	char *address;		/* MAC address */
	char *driver;		/* Driver (for whitelisting purpose) */
	int   flags;		/* Flags (IFF_*) */
	int   mtu;		/* MTU */
	int   type;		/* Type (see IFACE_*_T) */
	int   vlanid;		/* If a VLAN, what is the VLAN ID? */
	struct interfaces_device *lower; /* Lower interface (for a VLAN for example) */
	struct interfaces_device *upper; /* Upper interface (for a bridge or a bond) */

	/* The following are OS specific. Should be static (no free function) */
#ifdef HOST_OS_LINUX
	int lower_idx;		/* Index to lower interface */
	int upper_idx;		/* Index to upper interface */
#endif
};
struct interfaces_address {
	TAILQ_ENTRY(interfaces_address) next;
	int index;			 /* Index */
	int flags;			 /* Flags */
	struct sockaddr_storage address; /* Address */

	/* The following are OS specific. */
	/* Nothing yet. */
};
TAILQ_HEAD(interfaces_device_list,  interfaces_device);
TAILQ_HEAD(interfaces_address_list, interfaces_address);
void interfaces_free_device(struct interfaces_device *);
void interfaces_free_address(struct interfaces_address *);
void interfaces_free_devices(struct interfaces_device_list *);
void interfaces_free_addresses(struct interfaces_address_list *);
struct interfaces_device* interfaces_indextointerface(
	struct interfaces_device_list *,
	int);
struct interfaces_device* interfaces_nametointerface(
	struct interfaces_device_list *,
	const char *);

void interfaces_helper_promisc(struct lldpd *,
    struct lldpd_hardware *);
void interfaces_helper_whitelist(struct lldpd *,
    struct interfaces_device_list *);
void interfaces_helper_chassis(struct lldpd *,
    struct interfaces_device_list *);
void interfaces_helper_add_hardware(struct lldpd *,
    struct lldpd_hardware *);
void interfaces_helper_physical(struct lldpd *,
    struct interfaces_device_list *,
    struct lldpd_ops *,
    int(*init)(struct lldpd *, struct lldpd_hardware *));
void interfaces_helper_port_name_desc(struct lldpd *,
    struct lldpd_hardware *,
    struct interfaces_device *);
void interfaces_helper_mgmt(struct lldpd *,
    struct interfaces_address_list *);
#ifdef ENABLE_DOT1
void interfaces_helper_vlan(struct lldpd *,
    struct interfaces_device_list *);
#endif
int interfaces_send_helper(struct lldpd *,
    struct lldpd_hardware *, char *, size_t);

void interfaces_setup_multicast(struct lldpd *, const char *, int);
int interfaces_routing_enabled(struct lldpd *);
void interfaces_cleanup(struct lldpd *);

#ifdef HOST_OS_LINUX
/* netlink.c */
struct interfaces_device_list  *netlink_get_interfaces(struct lldpd *);
struct interfaces_address_list *netlink_get_addresses(struct lldpd *);
void netlink_cleanup(struct lldpd *);
struct lldpd_netlink;
#endif

#ifndef HOST_OS_LINUX
int ifbpf_phys_init(struct lldpd *, struct lldpd_hardware *);
#endif

/* pattern.c */
int pattern_match(char *, char *, int);

struct lldpd {
	int			 g_sock;
	struct event_base	*g_base;
#ifdef USE_SNMP
#endif

	struct lldpd_config	 g_config;

	struct protocol		*g_protocols;
	int			 g_lastrid;
	struct event		*g_main_loop;
	struct event		*g_cleanup_timer;
#ifdef USE_SNMP
	int			 g_snmp;
	struct event		*g_snmp_timeout;
	void			*g_snmp_fds;
	const char		*g_snmp_agentx;
#endif /* USE_SNMP */

	/* Unix socket handling */
	const char		*g_ctlname;
	int			 g_ctl;
	struct event		*g_iface_event; /* Triggered when there is an interface change */
	struct event		*g_iface_timer_event; /* Triggered one second after last interface change */
	void(*g_iface_cb)(struct lldpd *);	      /* Called when there is an interface change */

	char			*g_lsb_release;

#ifdef HOST_OS_LINUX
	struct lldpd_netlink	*g_netlink;
#endif

	struct lldpd_port	*g_default_local_port;
#define LOCAL_CHASSIS(cfg) ((struct lldpd_chassis *)(TAILQ_FIRST(&cfg->g_chassis)))
	TAILQ_HEAD(, lldpd_chassis) g_chassis;
	TAILQ_HEAD(, lldpd_hardware) g_hardware;
};

#endif /* _LLDPD_H */