1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21/*
22 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23 * Use is subject to license terms.
24 */
25
26#ifndef	INTERFACE_H
27#define	INTERFACE_H
28
29/*
30 * Interface.[ch] encapsulate all of the agent's knowledge of network
31 * interfaces from the DHCP agent's perspective.  See interface.c for
32 * documentation on how to use the exported functions.  Note that there are not
33 * functional interfaces for manipulating all of the fields in a PIF or LIF --
34 * please read the comments in the structure definitions below for the rules on
35 * accessing various fields.
36 */
37
38#ifdef	__cplusplus
39extern "C" {
40#endif
41
42#include <netinet/in.h>
43#include <net/if.h>			/* IFNAMSIZ */
44#include <sys/types.h>
45#include <netinet/dhcp.h>
46#include <dhcpagent_ipc.h>
47#include <libinetutil.h>
48
49#include "common.h"
50#include "util.h"
51
52#define	V4_PART_OF_V6(v6)	v6._S6_un._S6_u32[3]
53
54struct dhcp_pif_s {
55	dhcp_pif_t	*pif_next;	/* Note: must be first */
56	dhcp_pif_t	*pif_prev;
57	dhcp_lif_t	*pif_lifs;	/* pointer to logical interface list */
58	uint32_t	pif_index;	/* interface index */
59	uint16_t	pif_max;	/* largest DHCP packet on this if */
60	uchar_t		*pif_hwaddr;	/* our link-layer address */
61	uchar_t		pif_hwlen;	/* our link-layer address len */
62	uchar_t		pif_hwtype;	/* type of link-layer */
63	boolean_t	pif_isv6;
64	boolean_t	pif_running;	/* interface is running */
65	uint_t		pif_hold_count;	/* reference count */
66	char		pif_name[LIFNAMSIZ];
67	char		pif_grifname[LIFNAMSIZ];
68	uint32_t	pif_grindex;	/* interface index for pif_grifname */
69	boolean_t	pif_under_ipmp;	/* is an ipmp underlying interface */
70};
71
72struct dhcp_lif_s {
73	dhcp_lif_t	*lif_next;	/* Note: must be first */
74	dhcp_lif_t	*lif_prev;
75	dhcp_pif_t	*lif_pif;	/* backpointer to parent physical if */
76	dhcp_smach_t	*lif_smachs;	/* pointer to list of state machines */
77	dhcp_lease_t	*lif_lease;	/* backpointer to lease holding LIF */
78	uint64_t	lif_flags;	/* Interface flags (IFF_*) */
79	int		lif_sock_ip_fd;	/* Bound to addr.BOOTPC for src addr */
80	iu_event_id_t	lif_packet_id;	/* event packet id */
81	uint_t		lif_max;	/* maximum IP message size */
82	uint_t		lif_hold_count;	/* reference count */
83	boolean_t	lif_dad_wait;	/* waiting for DAD resolution */
84	boolean_t	lif_removed;	/* removed from list */
85	boolean_t	lif_plumbed;	/* interface plumbed by dhcpagent */
86	boolean_t	lif_expired;	/* lease has evaporated */
87	const char	*lif_declined;	/* reason to refuse this address */
88	uint32_t	lif_iaid;	/* unique and stable identifier */
89	iu_event_id_t	lif_iaid_id;	/* for delayed writes to /etc */
90
91	/*
92	 * While in any states except ADOPTING, INIT, INFORMATION and
93	 * INFORM_SENT, the following three fields are equal to what we believe
94	 * the current address, netmask, and broadcast address on the interface
95	 * to be.  This is so we can detect if the user changes them and
96	 * abandon the interface.
97	 */
98
99	in6_addr_t	lif_v6addr;	/* our IP address */
100	in6_addr_t	lif_v6mask;	/* our netmask */
101	in6_addr_t	lif_v6peer;	/* our broadcast or peer address */
102
103	dhcp_timer_t	lif_preferred;	/* lease preferred timer (v6 only) */
104	dhcp_timer_t	lif_expire;	/* lease expire timer */
105
106	char		lif_name[LIFNAMSIZ];
107};
108#define	lif_addr	V4_PART_OF_V6(lif_v6addr)
109#define	lif_netmask	V4_PART_OF_V6(lif_v6mask)
110#define	lif_peer	V4_PART_OF_V6(lif_v6peer)
111#define	lif_broadcast	V4_PART_OF_V6(lif_v6peer)
112
113/* used by expired_lif_state to express state of DHCP interfaces */
114typedef enum dhcp_expire_e {
115	DHCP_EXP_NOLIFS,
116	DHCP_EXP_NOEXP,
117	DHCP_EXP_ALLEXP,
118	DHCP_EXP_SOMEEXP
119} dhcp_expire_t;
120
121/*
122 * A word on memory management and LIFs and PIFs:
123 *
124 * Since LIFs are often passed as context to callback functions, they cannot be
125 * freed when the interface they represent is dropped or released (or when
126 * those callbacks finally go off, they will be hosed).  To handle this
127 * situation, the structures are reference counted.  Here are the rules for
128 * managing these counts:
129 *
130 * A PIF is created through insert_pif().  Along with initializing the PIF,
131 * this puts a hold on the PIF.  A LIF is created through insert_lif().  This
132 * also initializes the LIF and places a hold on it.  The caller's hold on the
133 * underlying PIF is transferred to the LIF.
134 *
135 * Whenever a lease is released or dropped (implicitly or explicitly),
136 * remove_lif() is called, which sets the lif_removed flag and removes the
137 * interface from the internal list of managed interfaces.  Lastly,
138 * remove_lif() calls release_lif() to remove the hold acquired in
139 * insert_lif().  If this decrements the hold count on the interface to zero,
140 * then free() is called and the hold on the PIF is dropped.  If there are
141 * holds other than the hold acquired in insert_lif(), the hold count will
142 * still be > 0, and the interface will remain allocated (though dormant).
143 *
144 * Whenever a callback is scheduled against a LIF, another hold must be put on
145 * the ifslist through hold_lif().
146 *
147 * Whenever a callback is called back against a LIF, release_lif() must be
148 * called to decrement the hold count, which may end up freeing the LIF if the
149 * hold count becomes zero.
150 *
151 * Since some callbacks may take a long time to get called back (such as
152 * timeout callbacks for lease expiration, etc), it is sometimes more
153 * appropriate to cancel the callbacks and call release_lif() if the
154 * cancellation succeeds.  This is done in remove_lif() for the lease preferred
155 * and expire callbacks.
156 *
157 * In general, a callback may also call verify_lif() when it gets called back
158 * in addition to release_lif(), to make sure that the interface is still in
159 * fact under the dhcpagent's control.  To make coding simpler, there is a
160 * third function, verify_smach(), which performs both the release_lif() and
161 * the verify_lif() on all LIFs controlled by a state machine.
162 */
163
164extern dhcp_pif_t *v4root;
165extern dhcp_pif_t *v6root;
166
167dhcp_pif_t	*insert_pif(const char *, boolean_t, int *);
168void		hold_pif(dhcp_pif_t *);
169void		release_pif(dhcp_pif_t *);
170dhcp_pif_t	*lookup_pif_by_uindex(uint16_t, dhcp_pif_t *, boolean_t);
171dhcp_pif_t	*lookup_pif_by_name(const char *, boolean_t);
172void		pif_status(dhcp_pif_t *, boolean_t);
173
174dhcp_lif_t	*insert_lif(dhcp_pif_t *, const char *, int *);
175void		hold_lif(dhcp_lif_t *);
176void		release_lif(dhcp_lif_t *);
177void		remove_lif(dhcp_lif_t *);
178dhcp_lif_t	*lookup_lif_by_name(const char *, const dhcp_pif_t *);
179boolean_t	verify_lif(const dhcp_lif_t *);
180dhcp_lif_t	*plumb_lif(dhcp_pif_t *, const in6_addr_t *);
181void		unplumb_lif(dhcp_lif_t *);
182dhcp_lif_t	*attach_lif(const char *, boolean_t, int *);
183int		set_lif_dhcp(dhcp_lif_t *);
184void		set_lif_deprecated(dhcp_lif_t *);
185boolean_t	clear_lif_deprecated(dhcp_lif_t *);
186boolean_t	open_ip_lif(dhcp_lif_t *, in_addr_t, boolean_t);
187void		close_ip_lif(dhcp_lif_t *);
188void		lif_mark_decline(dhcp_lif_t *, const char *);
189boolean_t	schedule_lif_timer(dhcp_lif_t *, dhcp_timer_t *,
190		    iu_tq_callback_t *);
191void		cancel_lif_timers(dhcp_lif_t *);
192dhcp_expire_t	expired_lif_state(dhcp_smach_t *);
193dhcp_lif_t	*find_expired_lif(dhcp_smach_t *);
194
195uint_t		get_max_mtu(boolean_t);
196void		remove_v6_strays(void);
197
198#ifdef	__cplusplus
199}
200#endif
201
202#endif	/* INTERFACE_H */
203