aboutsummaryrefslogtreecommitdiff
path: root/net/dhcpv6.h
blob: 65c8e4c71d35e2da4fef9bc79d89b6b418251d53 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
/* SPDX-License-Identifier: GPL-2.0+ */
/*
 * Copyright (C) Microsoft Corporation
 * Author: Sean Edmond <seanedmond@microsoft.com>
 *
 */

#ifndef __DHCP6_H__
#define __DHCP6_H__

/* Message types */
#define DHCP6_MSG_SOLICIT	1
#define DHCP6_MSG_ADVERTISE	2
#define DHCP6_MSG_REQUEST	3
#define DHCP6_MSG_REPLY		7

/* Option Codes */
#define DHCP6_OPTION_CLIENTID		1
#define DHCP6_OPTION_SERVERID		2
#define DHCP6_OPTION_IA_NA		3
#define DHCP6_OPTION_IA_TA		4
#define DHCP6_OPTION_IAADDR		5
#define DHCP6_OPTION_ORO		6
#define DHCP6_OPTION_PREFERENCE		7
#define DHCP6_OPTION_ELAPSED_TIME	8
#define DHCP6_OPTION_STATUS_CODE	13
#define DHCP6_OPTION_OPT_BOOTFILE_URL	59
#define DHCP6_OPTION_OPT_BOOTFILE_PARAM	60
#define DHCP6_OPTION_SOL_MAX_RT		82
#define DHCP6_OPTION_CLIENT_ARCH_TYPE	61
#define DHCP6_OPTION_VENDOR_CLASS	16
#define DHCP6_OPTION_NII		62

/* DUID */
#define DUID_TYPE_LL		3
#define DUID_HW_TYPE_ENET	1
#define DUID_LL_SIZE		(sizeof(struct dhcp6_option_duid_ll) + ETH_ALEN)
#define DUID_MAX_SIZE		DUID_LL_SIZE /* only supports DUID-LL currently */

/* vendor-class-data to send in vendor clas option */
#define DHCP6_VCI_STRING	"U-Boot"

#define DHCP6_MULTICAST_ADDR	"ff02::1:2"	/* DHCP multicast address */

/* DHCP6 States supported */
enum dhcp6_state {
	DHCP6_INIT,
	DHCP6_SOLICIT,
	DHCP6_REQUEST,
	DHCP6_DONE,
	DHCP6_FAIL,
};

/* DHCP6 Status codes */
enum dhcp6_status {
	DHCP6_SUCCESS = 0,
	DHCP6_UNSPEC_FAIL = 1,
	DHCP6_NO_ADDRS_AVAIL = 2,
	DHCP6_NO_BINDING = 3,
	DHCP6_NOT_ON_LINK = 4,
	DHCP6_USE_MULTICAST = 5,
	DHCP6_NO_PREFIX_AVAIL = 6,
};

/* DHCP6 message header format */
struct dhcp6_hdr {
	unsigned int msg_type : 8;	/* message type */
	unsigned int trans_id : 24;	/* transaction ID */
} __packed;

/* DHCP6 option header format */
struct dhcp6_option_hdr {
	__be16	option_id;	/* option id */
	__be16	option_len;	/* Option length */
	u8	option_data[0];	/* Option data */
} __packed;

/* DHCP6_OPTION_CLIENTID option (DUID-LL) */
struct dhcp6_option_duid_ll {
	__be16	duid_type;
	__be16	hw_type;
	u8	ll_addr[0];
} __packed;

/* DHCP6_OPTION_ELAPSED_TIME option */
struct dhcp6_option_elapsed_time {
	__be16	elapsed_time;
} __packed;

/* DHCP6_OPTION_IA_TA option */
struct dhcp6_option_ia_ta {
	__be32	iaid;
	u8	ia_ta_options[0];
} __packed;

/* DHCP6_OPTION_IA_NA option */
struct dhcp6_option_ia_na {
	__be32	iaid;
	__be32	t1;
	__be32	t2;
	u8	ia_na_options[0];
} __packed;

/* OPTION_ORO option */
struct dhcp6_option_oro  {
	__be16	req_option_code[0];
} __packed;

/* DHCP6_OPTION_CLIENT_ARCH_TYPE option */
struct dhcp6_option_client_arch {
	__be16	arch_type[0];
} __packed;

/* vendor-class-data inside OPTION_VENDOR_CLASS option */
struct vendor_class_data {
	__be16	vendor_class_len;
	u8	opaque_data[0];
} __packed;

/* DHCP6_OPTION_VENDOR_CLASS option */
struct dhcp6_option_vendor_class {
	__be32				enterprise_number;
	struct vendor_class_data	vendor_class_data[0];
} __packed;

/**
 * struct dhcp6_rx_pkt_status - Structure that holds status
 *                              from a received message
 * @client_id_match: Client ID was found and matches DUID sent
 * @server_id_found: Server ID was found in the message
 * @server_uid_ptr: Pointer to received server ID
 * @server_uid_size: Size of received server ID
 * @ia_addr_found: IA addr option was found in received message
 * @ia_addr_ipv6: The IPv6 address received in IA
 * @ia_status_code: Status code received in the IA
 * @status_code: Top-level status code received
 * @preference: Preference code received
 */
struct dhcp6_rx_pkt_status {
	bool			client_id_match;
	bool			server_id_found;
	uchar			*server_uid_ptr;
	u16			server_uid_size;
	bool			ia_addr_found;
	struct in6_addr		ia_addr_ipv6;
	enum dhcp6_status	ia_status_code;
	enum dhcp6_status	status_code;
	u8			preference;
};

/**
 * struct dhcp6_server_uid - Structure that holds the server UID
 *                             received from an ADVERTISE and saved
 *                             given the server selection criteria.
 * @uid_ptr: Dynamically allocated and copied server UID
 * @uid_size: Size of the server UID in uid_ptr (in bytes)
 * @preference: Preference code associated with this server UID
 */
struct dhcp6_server_uid {
	uchar	*uid_ptr;
	u16	uid_size;
	u8	preference;
};

/**
 * struct dhcp6_sm_params - Structure that holds DHCP6
 *                          state machine parameters
 * @curr_state: current DHCP6 state
 * @next_state: next DHCP6 state
 * @dhcp6_start_ms: timestamp DHCP6 start
 * @dhcp6_retry_start_ms: timestamp of current TX message start
 * @dhcp6_retry_ms: timestamp of last retransmission
 * @retry_cnt: retry count
 * @trans_id: transaction ID
 * @ia_id: transmitted IA ID
 * @irt_ms: Initial retransmission time (in ms)
 * @mrt_ms: Maximum retransmission time (in ms)
 * @mrc: Maximum retransmission count
 * @mrd_ms: Maximum retransmission duration (in ms)
 * @rt_ms: retransmission timeout (is ms)
 * @rt_prev_ms: previous retransmission timeout
 * @rx_status: Status from received message
 * @server_uid: Saved Server UID for selected server
 * @duid: pointer to transmitted Client DUID
 */
struct dhcp6_sm_params {
	enum dhcp6_state		curr_state;
	enum dhcp6_state		next_state;
	ulong				dhcp6_start_ms;
	ulong				dhcp6_retry_start_ms;
	ulong				dhcp6_retry_ms;
	u32				retry_cnt;
	u32				trans_id;
	u32				ia_id;
	int				irt_ms;
	int				mrt_ms;
	int				mrc;
	int				mrd_ms;
	int				rt_ms;
	int				rt_prev_ms;
	struct dhcp6_rx_pkt_status	rx_status;
	struct dhcp6_server_uid		server_uid;
	char				duid[DUID_MAX_SIZE];
};

/* Starts a DHCPv6 4-message exchange as a DHCPv6 client. On successful exchange,
 * the DHCPv6 state machine will transition from internal states:
 *	DHCP6_INIT->DHCP6_SOLICIT->DHCP6_REQUEST->DHCP6_DONE
 *
 * Transmitted SOLICIT and REQUEST packets will set/request the minimum required
 * DHCPv6 options to PXE boot.
 *
 * After a successful exchange, the DHCPv6 assigned address will be set in net_ip6
 *
 * Additionally, the following will be set after receiving these options:
 * DHCP6_OPTION_OPT_BOOTFILE_URL (option 59) -> net_server_ip6, net_boot_file_name
 * DHCP6_OPTION_OPT_BOOTFILE_PARAM (option 60) - > pxelinux_configfile
 *
 * Illustration of a 4-message exchange with 2 servers (copied from
 * https://www.rfc-editor.org/rfc/rfc8415):
 *
 *               Server                          Server
 *           (not selected)      Client        (selected)
 *
 *                 v               v               v
 *                 |               |               |
 *                 |     Begins initialization     |
 *                 |               |               |
 *    start of     | _____________/|\_____________ |
 *    4-message    |/ Solicit      | Solicit      \|
 *    exchange     |               |               |
 *             Determines          |          Determines
 *            configuration        |         configuration
 *                 |               |               |
 *                 |\              |  ____________/|
 *                 | \________     | /Advertise    |
 *                 | Advertise\    |/              |
 *                 |           \   |               |
 *                 |      Collects Advertises      |
 *                 |             \ |               |
 *                 |     Selects configuration     |
 *                 |               |               |
 *                 | _____________/|\_____________ |
 *                 |/ Request      |  Request     \|
 *                 |               |               |
 *                 |               |     Commits configuration
 *                 |               |               |
 *    end of       |               | _____________/|
 *    4-message    |               |/ Reply        |
 *    exchange     |               |               |
 *                 |    Initialization complete    |
 *                 |               |               |
 */
void dhcp6_start(void);

#endif /* __DHCP6_H__ */