xref: /illumos-gate/usr/src/cmd/cmd-inet/sbin/dhcpagent/packet.h (revision 8119dad84d6416f13557b0ba8e2aaf9064cbcfd3)
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 2007 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  * Copyright (c) 2016, Chris Fraire <cfraire@me.com>.
25  */
26 
27 #ifndef	_PACKET_H
28 #define	_PACKET_H
29 
30 #include <sys/types.h>
31 #include <netinet/in.h>
32 #include <netinet/dhcp.h>
33 #include <netinet/dhcp6.h>
34 #include <dhcp_impl.h>
35 
36 #include "common.h"
37 
38 /*
39  * packet.[ch] contain routines for manipulating, setting, and
40  * transmitting DHCP/BOOTP packets.  see packet.c for descriptions on
41  * how to use the exported functions.
42  */
43 
44 #ifdef	__cplusplus
45 extern "C" {
46 #endif
47 
48 /*
49  * data type for recv_pkt().  needed because we may want to wait for
50  * several kinds of packets at once, and the existing enumeration of
51  * DHCP packet types does not provide a way to do that easily.  here,
52  * we light a different bit in the enumeration for each type of packet
53  * we want to receive.
54  *
55  * Note that for DHCPv6, types 4 (CONFIRM), 5 (RENEW), 6 (REBIND), 12
56  * (RELAY-FORW, and 13 (RELAY-REPL) are not in the table.  They're never
57  * received by a client, so there's no reason to process them.  (SOLICIT,
58  * REQUEST, DECLINE, RELEASE, and INFORMATION-REQUEST are also never seen by
59  * clients, but are included for consistency.)
60  *
61  * Note also that the symbols are named for the DHCPv4 message types, and that
62  * DHCPv6 has analogous message types.
63  */
64 
65 typedef enum {
66 
67 	DHCP_PUNTYPED	= 0x001,	/* untyped (BOOTP) message */
68 	DHCP_PDISCOVER	= 0x002,	/* in v6: SOLICIT (1) */
69 	DHCP_POFFER 	= 0x004,	/* in v6: ADVERTISE (2) */
70 	DHCP_PREQUEST	= 0x008,	/* in v6: REQUEST (3) */
71 	DHCP_PDECLINE	= 0x010,	/* in v6: DECLINE (9) */
72 	DHCP_PACK	= 0x020,	/* in v6: REPLY (7), status == 0 */
73 	DHCP_PNAK	= 0x040,	/* in v6: REPLY (7), status != 0 */
74 	DHCP_PRELEASE	= 0x080,	/* in v6: RELEASE (8) */
75 	DHCP_PINFORM	= 0x100,	/* in v6: INFORMATION-REQUEST (11) */
76 	DHCP_PRECONFIG	= 0x200		/* v6 only: RECONFIGURE (10) */
77 
78 } dhcp_message_type_t;
79 
80 /*
81  * A dhcp_pkt_t is used by the output-side packet manipulation functions.
82  * While the structure is not strictly necessary, it allows a better separation
83  * of functionality since metadata about the packet (such as its current
84  * length) is stored along with the packet.
85  *
86  * Note that 'pkt' points to a dhcpv6_message_t if the packet is IPv6.
87  */
88 
89 typedef struct dhcp_pkt_s {
90 	PKT		*pkt;		/* the real underlying packet */
91 	unsigned int	pkt_max_len; 	/* its maximum length */
92 	unsigned int	pkt_cur_len;	/* its current length */
93 	boolean_t	pkt_isv6;
94 } dhcp_pkt_t;
95 
96 /*
97  * a `stop_func_t' is used by parts of dhcpagent that use the
98  * retransmission capability of send_pkt().  this makes it so the
99  * callers of send_pkt() decide when to stop retransmitting, which
100  * makes more sense than hardcoding their instance-specific cases into
101  * packet.c
102  */
103 
104 typedef boolean_t stop_func_t(dhcp_smach_t *, unsigned int);
105 
106 /*
107  * Default I/O and interface control sockets.
108  */
109 extern int v6_sock_fd;
110 extern int v4_sock_fd;
111 
112 extern const in6_addr_t ipv6_all_dhcp_relay_and_servers;
113 extern const in6_addr_t my_in6addr_any;
114 
115 PKT_LIST	*alloc_pkt_entry(size_t, boolean_t);
116 void		free_pkt_entry(PKT_LIST *);
117 void		free_pkt_list(PKT_LIST **);
118 uchar_t		pkt_recv_type(const PKT_LIST *);
119 uint_t		pkt_get_xid(const PKT *, boolean_t);
120 dhcp_pkt_t	*init_pkt(dhcp_smach_t *, uchar_t);
121 boolean_t	remove_pkt_opt(dhcp_pkt_t *, uint_t);
122 boolean_t	update_v6opt_len(dhcpv6_option_t *, int);
123 void		*add_pkt_opt(dhcp_pkt_t *, uint_t, const void *, uint_t);
124 size_t		encode_dhcp_opt(void *, boolean_t, uint_t, const void *,
125 			uint_t);
126 void		*add_pkt_subopt(dhcp_pkt_t *, dhcpv6_option_t *, uint_t,
127 		    const void *, uint_t);
128 void		*add_pkt_opt16(dhcp_pkt_t *, uint_t, uint16_t);
129 void		*add_pkt_opt32(dhcp_pkt_t *, uint_t, uint32_t);
130 void		*add_pkt_prl(dhcp_pkt_t *, dhcp_smach_t *);
131 boolean_t	add_pkt_lif(dhcp_pkt_t *, dhcp_lif_t *, int, const char *);
132 void		stop_pkt_retransmission(dhcp_smach_t *);
133 void		retransmit_now(dhcp_smach_t *);
134 PKT_LIST	*recv_pkt(int, int, boolean_t);
135 boolean_t	pkt_v4_match(uchar_t, dhcp_message_type_t);
136 void		pkt_smach_enqueue(dhcp_smach_t *, PKT_LIST *);
137 boolean_t	send_pkt(dhcp_smach_t *, dhcp_pkt_t *, in_addr_t,
138 		    stop_func_t *);
139 boolean_t	send_pkt_v6(dhcp_smach_t *, dhcp_pkt_t *, in6_addr_t,
140 		    stop_func_t *, uint_t, uint_t);
141 boolean_t	dhcp_ip_default(void);
142 
143 #ifdef	__cplusplus
144 }
145 #endif
146 
147 #endif	/* _PACKET_H */
148