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
257
258
259
260
261
262
|
/*
* Copyright (c) 2008 Nicira Networks.
*
* 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 DHCP_H
#define DHCP_H 1
#include <stdint.h>
#include "packets.h"
#include "util.h"
struct ds;
struct ofpbuf;
/* Values for 'op' field. */
#define DHCP_BOOTREQUEST 1 /* Message sent by DHCP client. */
#define DHCP_BOOTREPLY 2 /* Message sent by DHCP server. */
/* Bits in 'flags' field. */
#define DHCP_FLAGS_BROADCAST 0x8000 /* Server must broadcast all replies. */
#define DHCP_FLAGS_MBZ 0x7fff /* Must be zero. */
/* First four bytes of 'options' field. */
#define DHCP_OPTS_COOKIE 0x63825363
#define DHCP_HEADER_LEN 236
struct dhcp_header {
uint8_t op; /* DHCP_BOOTREQUEST or DHCP_BOOTREPLY. */
uint8_t htype; /* ARP_HRD_ETHERNET (typically). */
uint8_t hlen; /* ETH_ADDR_LEN (typically). */
uint8_t hops; /* Hop count; set to 0 by client. */
uint32_t xid; /* Transaction ID. */
uint16_t secs; /* Since client started address acquisition. */
uint16_t flags; /* DHCP_FLAGS_*. */
uint32_t ciaddr; /* Client IP, if it has a lease for one. */
uint32_t yiaddr; /* Client ("your") IP address. */
uint32_t siaddr; /* Next server IP address. */
uint32_t giaddr; /* Relay agent IP address. */
uint8_t chaddr[16]; /* Client hardware address. */
char sname[64]; /* Optional server host name. */
char file[128]; /* Boot file name. */
/* Followed by variable-length options field. */
};
BUILD_ASSERT_DECL(DHCP_HEADER_LEN == sizeof(struct dhcp_header));
#define DHCP_ARGS \
DHCP_ARG(FIXED, 0) /* Fixed-length option (PAD and END only). */ \
DHCP_ARG(IP, 4) /* IP addresses. */ \
DHCP_ARG(SECS, 4) /* 32-bit duration in seconds. */ \
DHCP_ARG(STRING, 1) /* NVT string, optionally null-terminated. */ \
DHCP_ARG(UINT8, 1) /* 8-bit unsigned integer. */ \
DHCP_ARG(UINT16, 2) /* 16-bit unsigned integer. */ \
DHCP_ARG(UINT32, 4) /* 32-bit unsigned integer. */ \
DHCP_ARG(BOOLEAN, 1) /* Boolean octet (0 or 1). */
/* DHCP option argument types. */
enum dhcp_arg_type {
#define DHCP_ARG(NAME, SIZE) DHCP_ARG_##NAME,
DHCP_ARGS
#undef DHCP_ARG
};
#define DHCP_MSGS \
DHCP_MSG(DHCPDISCOVER, 1) /* Client->server: What IPs are available? */ \
DHCP_MSG(DHCPOFFER, 2) /* Server->client: This IP is available. */ \
DHCP_MSG(DHCPREQUEST, 3) /* Client->server: I want that IP. */ \
DHCP_MSG(DHCPDECLINE, 4) /* Client->server: That IP is in use!. */ \
DHCP_MSG(DHCPACK, 5) /* Server->client: You can have that IP. */ \
DHCP_MSG(DHCPNAK, 6) /* Server->client: You can't have that IP. */ \
DHCP_MSG(DHCPRELEASE, 7) /* Client->server: I'm done with this IP. */ \
DHCP_MSG(DCHPINFORM, 8) /* Client->server: I'm using this IP. */
/* DHCP message type (this is the argument for the DHCP_MSG_TYPE option). */
enum dhcp_msg_type {
#define DHCP_MSG(NAME, VALUE) NAME = VALUE,
DHCP_MSGS
#undef DHCP_MSG
};
const char *dhcp_type_name(enum dhcp_msg_type);
/* DHCP allows for 256 standardized options and 256 vendor-specific options.
* We put them in a single array, with the standard options at the
* beginning. */
#define DHCP_N_OPTIONS 512
#define DHCP_VENDOR_OFS 256
/* DHCP options. */
#define DHCP_OPTS \
/* arg min max */ \
/* name code type args args */ \
DHCP_OPT(PAD, 0, FIXED, 0, 0) \
DHCP_OPT(END, 255, FIXED, 0, 0) \
DHCP_OPT(SUBNET_MASK, 1, IP, 1, 1) \
DHCP_OPT(TIME_OFFSET, 2, SECS, 1, 1) \
DHCP_OPT(ROUTER, 3, IP, 1, SIZE_MAX) \
/* Time Server Option is obsolete. */ \
/* Name Server Option is obsolete. */ \
DHCP_OPT(DNS_SERVER, 6, IP, 1, SIZE_MAX) \
/* Log Server Option is obsolete. */ \
/* Cookie Server Option is obsolete. */ \
DHCP_OPT(LPR_SERVER, 9, IP, 1, SIZE_MAX) \
/* Impress Server Option is obsolete. */ \
/* Resource Location Server Option is obsolete. */ \
DHCP_OPT(HOST_NAME, 12, STRING, 1, SIZE_MAX) \
DHCP_OPT(BOOT_FILE_SIZE, 13, UINT16, 1, 1) \
/* Merit Dump File option is obsolete. */ \
DHCP_OPT(DOMAIN_NAME, 15, STRING, 1, SIZE_MAX) \
/* Swap Server option is obsolete. */ \
DHCP_OPT(ROOT_PATH, 17, STRING, 1, SIZE_MAX) \
DHCP_OPT(EXTENSIONS_PATH, 18, STRING, 1, SIZE_MAX) \
DHCP_OPT(IP_FORWARDING, 19, BOOLEAN, 1, 1) \
DHCP_OPT(SOURCE_ROUTING, 20, BOOLEAN, 1, 1) \
DHCP_OPT(POLICY_FILTER, 21, IP, 2, SIZE_MAX) \
DHCP_OPT(MAX_DGRAM_REASSEMBLY, 22, UINT16, 1, 1) \
DHCP_OPT(IP_TTL, 23, UINT8, 1, 1) \
DHCP_OPT(PATH_MTU_TIMEOUT, 24, SECS, 1, 1) \
DHCP_OPT(PATH_MTU_PLATEAU, 25, UINT16, 2, SIZE_MAX) \
DHCP_OPT(MTU, 26, UINT16, 1, 1) \
DHCP_OPT(ALL_SUBNETS_ARE_LOCAL, 27, BOOLEAN, 1, 1) \
DHCP_OPT(BROADCAST_ADDRESS, 28, IP, 1, 1) \
DHCP_OPT(PERFORM_MASK_DISCOVERY, 29, BOOLEAN, 1, 1) \
DHCP_OPT(MASK_SUPPLIER, 30, BOOLEAN, 1, 1) \
DHCP_OPT(PERFORM_ROUTER_DISCOVERY, 31, BOOLEAN, 1, 1) \
DHCP_OPT(ROUTER_SOLICITATION, 32, IP, 1, 1) \
DHCP_OPT(STATIC_ROUTE, 33, IP, 2, SIZE_MAX) \
/* Trailer Encapsulation Option is obsolete. */ \
DHCP_OPT(ARP_CACHE_TIMEOUT, 35, SECS, 1, 1) \
DHCP_OPT(ETHERNET_ENCAPSULATION, 36, BOOLEAN, 1, 1) \
DHCP_OPT(TCP_TTL, 37, UINT8, 1, 1) \
DHCP_OPT(TCP_KEEPALIVE_INTERVAL, 38, SECS, 1, 1) \
DHCP_OPT(TCP_KEEPALIVE_GARBAGE, 39, BOOLEAN, 1, 1) \
DHCP_OPT(NIS_DOMAIN, 40, STRING, 1, SIZE_MAX) \
DHCP_OPT(NIS_SERVERS, 41, IP, 1, SIZE_MAX) \
DHCP_OPT(NTP_SERVERS, 42, IP, 1, SIZE_MAX) \
DHCP_OPT(VENDOR_SPECIFIC, 43, UINT8, 1, SIZE_MAX) \
DHCP_OPT(NETBIOS_NS, 44, IP, 1, SIZE_MAX) \
DHCP_OPT(NETBIOS_DDS, 45, IP, 1, SIZE_MAX) \
DHCP_OPT(NETBIOS_NODE_TYPE, 46, UINT8, 1, 1) \
DHCP_OPT(NETBIOS_SCOPE, 47, STRING, 1, SIZE_MAX) \
DHCP_OPT(X_FONT_SERVER, 48, IP, 1, SIZE_MAX) \
DHCP_OPT(XDM, 49, IP, 1, SIZE_MAX) \
DHCP_OPT(NISPLUS_DOMAIN, 64, STRING, 1, SIZE_MAX) \
DHCP_OPT(NISPLUS_SERVERS, 65, IP, 1, SIZE_MAX) \
DHCP_OPT(MOBILE_IP_HOME_AGENT, 68, IP, 0, SIZE_MAX) \
DHCP_OPT(SMTP_SERVER, 69, IP, 1, SIZE_MAX) \
DHCP_OPT(POP3_SERVER, 70, IP, 1, SIZE_MAX) \
DHCP_OPT(NNTP_SERVER, 71, IP, 1, SIZE_MAX) \
DHCP_OPT(WWW_SERVER, 72, IP, 1, SIZE_MAX) \
DHCP_OPT(FINGER_SERVER, 73, IP, 1, SIZE_MAX) \
DHCP_OPT(IRC_SERVER, 74, IP, 1, SIZE_MAX) \
/* StreetTalk Server Option is obsolete. */ \
/* StreetTalk Directory Assistance Server Option is obsolete. */ \
DHCP_OPT(REQUESTED_IP, 50, IP, 1, 1) \
DHCP_OPT(LEASE_TIME, 51, SECS, 1, 1) \
DHCP_OPT(OPTION_OVERLOAD, 52, UINT8, 1, 1) \
DHCP_OPT(TFTP_SERVER, 66, STRING, 1, SIZE_MAX) \
DHCP_OPT(BOOTFILE_NAME, 67, STRING, 1, SIZE_MAX) \
DHCP_OPT(DHCP_MSG_TYPE, 53, UINT8, 1, 1) \
DHCP_OPT(SERVER_IDENTIFIER, 54, IP, 1, 1) \
DHCP_OPT(PARAMETER_REQUEST_LIST, 55, UINT8, 1, SIZE_MAX) \
DHCP_OPT(MESSAGE, 56, STRING, 1, SIZE_MAX) \
DHCP_OPT(MAX_DHCP_MSG_SIZE, 57, UINT16, 1, 1) \
DHCP_OPT(T1, 58, SECS, 1, 1) \
DHCP_OPT(T2, 59, SECS, 1, 1) \
DHCP_OPT(VENDOR_CLASS, 60, STRING, 1, SIZE_MAX) \
DHCP_OPT(CLIENT_ID, 61, UINT8, 2, SIZE_MAX) \
DHCP_VNDOPT(OFP_CONTROLLER_VCONN, 1, STRING, 1, SIZE_MAX) \
DHCP_VNDOPT(OFP_PKI_URI, 2, STRING, 1, SIZE_MAX)
/* Shorthand for defining vendor options (used above). */
#define DHCP_VNDOPT(NAME, CODE, ARG, MIN, MAX) \
DHCP_OPT(NAME, (CODE) + DHCP_VENDOR_OFS, ARG, MIN, MAX)
/* DHCP option codes. */
enum {
#define DHCP_OPT(NAME, VALUE, ARGTYPE, MIN_ARGS, MAX_ARGS) \
DHCP_CODE_##NAME = VALUE,
DHCP_OPTS
#undef DHCP_OPT
};
/* The contents of a DHCP option.
*
* DHCP options can (rarely) be present but lack content. To represent such an
* option, 'n' is 0 and 'data' is non-null (but does not point to anything
* useful). */
struct dhcp_option {
size_t n; /* Number of bytes of data. */
void *data; /* Data. */
};
const char *dhcp_option_to_string(const struct dhcp_option *, int code,
struct ds *);
bool dhcp_option_equals(const struct dhcp_option *,
const struct dhcp_option *);
/* Abstracted DHCP protocol message, to make them easier to manipulate than
* through raw protocol buffers. */
struct dhcp_msg {
/* For use by calling code. */
uint8_t op; /* DHCP_BOOTREQUEST or DHCP_BOOTREPLY. */
uint32_t xid; /* Transaction ID. */
uint16_t secs; /* Since client started address acquisition. */
uint16_t flags; /* DHCP_FLAGS_*. */
uint32_t ciaddr; /* Client IP, if it has a lease for one. */
uint32_t yiaddr; /* Client ("your") IP address. */
uint32_t siaddr; /* Next server IP address. */
uint32_t giaddr; /* Relay agent IP address. */
uint8_t chaddr[ETH_ADDR_LEN]; /* Client hardware address. */
enum dhcp_msg_type type; /* DHCP_CODE_DHCP_MSG_TYPE option argument. */
struct dhcp_option options[DHCP_N_OPTIONS]; /* Indexed by option code. */
/* For direct use only by dhcp_msg_*() functions. */
uint8_t *data;
size_t data_used, data_allocated;
};
void dhcp_msg_init(struct dhcp_msg *);
void dhcp_msg_uninit(struct dhcp_msg *);
void dhcp_msg_copy(struct dhcp_msg *, const struct dhcp_msg *);
void dhcp_msg_put(struct dhcp_msg *, int code, const void *, size_t);
void dhcp_msg_put_bool(struct dhcp_msg *, int code, bool);
void dhcp_msg_put_secs(struct dhcp_msg *, int code, uint32_t);
void dhcp_msg_put_ip(struct dhcp_msg *, int code, uint32_t);
void dhcp_msg_put_string(struct dhcp_msg *, int code, const char *);
void dhcp_msg_put_uint8(struct dhcp_msg *, int code, uint8_t);
void dhcp_msg_put_uint8_array(struct dhcp_msg *, int code,
const uint8_t[], size_t n);
void dhcp_msg_put_uint16(struct dhcp_msg *, int code, uint16_t);
void dhcp_msg_put_uint16_array(struct dhcp_msg *, int code,
const uint16_t[], size_t n);
const void *dhcp_msg_get(const struct dhcp_msg *, int code, size_t offset,
size_t size);
bool dhcp_msg_get_bool(const struct dhcp_msg *, int code,
size_t offset, bool *);
bool dhcp_msg_get_secs(const struct dhcp_msg *, int code,
size_t offset, uint32_t *);
bool dhcp_msg_get_ip(const struct dhcp_msg *, int code,
size_t offset, uint32_t *);
char *dhcp_msg_get_string(const struct dhcp_msg *, int code);
bool dhcp_msg_get_uint8(const struct dhcp_msg *, int code,
size_t offset, uint8_t *);
bool dhcp_msg_get_uint16(const struct dhcp_msg *, int code,
size_t offset, uint16_t *);
const char *dhcp_msg_to_string(const struct dhcp_msg *, bool multiline,
struct ds *);
int dhcp_parse(struct dhcp_msg *, const struct ofpbuf *);
void dhcp_assemble(const struct dhcp_msg *, struct ofpbuf *);
#endif /* dhcp.h */
|
