ISC DHCP  4.4.3-P1
A reference DHCPv4 and DHCPv6 implementation
dhcp.h
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1 /* dhcp.h
2 
3  Protocol structures... */
4 
5 /*
6  * Copyright (C) 2004-2022 Internet Systems Consortium, Inc. ("ISC")
7  * Copyright (c) 1995-2003 by Internet Software Consortium
8  *
9  * This Source Code Form is subject to the terms of the Mozilla Public
10  * License, v. 2.0. If a copy of the MPL was not distributed with this
11  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
12  *
13  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
14  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
15  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
16  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
17  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
18  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
19  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
20  *
21  * Internet Systems Consortium, Inc.
22  * PO Box 360
23  * Newmarket, NH 03857 USA
24  * <info@isc.org>
25  * https://www.isc.org/
26  *
27  */
28 
29 #ifndef DHCP_H
30 #define DHCP_H
31 
32 #define DHCP_UDP_OVERHEAD (20 + /* IP header */ \
33  8) /* UDP header */
34 #define DHCP_SNAME_LEN 64
35 #define DHCP_FILE_LEN 128
36 #define DHCP_FIXED_NON_UDP 236
37 #define DHCP_FIXED_LEN (DHCP_FIXED_NON_UDP + DHCP_UDP_OVERHEAD)
38  /* Everything but options. */
39 #define BOOTP_MIN_LEN 300
40 
41 #define DHCP_MTU_MAX 1500
42 #define DHCP_MTU_MIN 576
43 
44 #define DHCP_MAX_OPTION_LEN (DHCP_MTU_MAX - DHCP_FIXED_LEN)
45 #define DHCP_MIN_OPTION_LEN (DHCP_MTU_MIN - DHCP_FIXED_LEN)
46 
47 struct dhcp_packet {
48  u_int8_t op; /* 0: Message opcode/type */
49  u_int8_t htype; /* 1: Hardware addr type (net/if_types.h) */
50  u_int8_t hlen; /* 2: Hardware addr length */
51  u_int8_t hops; /* 3: Number of relay agent hops from client */
52  u_int32_t xid; /* 4: Transaction ID */
53  u_int16_t secs; /* 8: Seconds since client started looking */
54  u_int16_t flags; /* 10: Flag bits */
55  struct in_addr ciaddr; /* 12: Client IP address (if already in use) */
56  struct in_addr yiaddr; /* 16: Client IP address */
57  struct in_addr siaddr; /* 18: IP address of next server to talk to */
58  struct in_addr giaddr; /* 20: DHCP relay agent IP address */
59  unsigned char chaddr [16]; /* 24: Client hardware address */
60  char sname [DHCP_SNAME_LEN]; /* 40: Server name */
61  char file [DHCP_FILE_LEN]; /* 104: Boot filename */
62  unsigned char options [DHCP_MAX_OPTION_LEN];
63  /* 212: Optional parameters
64  (actual length dependent on MTU). */
65 };
66 
67 /* BOOTP (rfc951) message types */
68 #define BOOTREQUEST 1
69 #define BOOTREPLY 2
70 
71 /* Possible values for flags field... */
72 #define BOOTP_BROADCAST 32768L
73 
74 /* Possible values for hardware type (htype) field... */
75 #define HTYPE_ETHER 1 /* Ethernet 10Mbps */
76 #define HTYPE_IEEE802 6 /* IEEE 802.2 Token Ring... */
77 #define HTYPE_FDDI 8 /* FDDI... */
78 #define HTYPE_INFINIBAND 32 /* IP over Infiniband */
79 #define HTYPE_IPMP 255 /* IPMP - random hw address - there
80  * is no standard for this so we
81  * just steal a type */
82 
83 #define HTYPE_RESERVED 0 /* RFC 5494 */
84 
85 /* Magic cookie validating dhcp options field (and bootp vendor
86  extensions field). */
87 #define DHCP_OPTIONS_COOKIE "\143\202\123\143"
88 
89 /* DHCP Option codes: */
90 
91 #define DHO_PAD 0
92 #define DHO_SUBNET_MASK 1
93 #define DHO_TIME_OFFSET 2
94 #define DHO_ROUTERS 3
95 #define DHO_TIME_SERVERS 4
96 #define DHO_NAME_SERVERS 5
97 #define DHO_DOMAIN_NAME_SERVERS 6
98 #define DHO_LOG_SERVERS 7
99 #define DHO_COOKIE_SERVERS 8
100 #define DHO_LPR_SERVERS 9
101 #define DHO_IMPRESS_SERVERS 10
102 #define DHO_RESOURCE_LOCATION_SERVERS 11
103 #define DHO_HOST_NAME 12
104 #define DHO_BOOT_SIZE 13
105 #define DHO_MERIT_DUMP 14
106 #define DHO_DOMAIN_NAME 15
107 #define DHO_SWAP_SERVER 16
108 #define DHO_ROOT_PATH 17
109 #define DHO_EXTENSIONS_PATH 18
110 #define DHO_IP_FORWARDING 19
111 #define DHO_NON_LOCAL_SOURCE_ROUTING 20
112 #define DHO_POLICY_FILTER 21
113 #define DHO_MAX_DGRAM_REASSEMBLY 22
114 #define DHO_DEFAULT_IP_TTL 23
115 #define DHO_PATH_MTU_AGING_TIMEOUT 24
116 #define DHO_PATH_MTU_PLATEAU_TABLE 25
117 #define DHO_INTERFACE_MTU 26
118 #define DHO_ALL_SUBNETS_LOCAL 27
119 #define DHO_BROADCAST_ADDRESS 28
120 #define DHO_PERFORM_MASK_DISCOVERY 29
121 #define DHO_MASK_SUPPLIER 30
122 #define DHO_ROUTER_DISCOVERY 31
123 #define DHO_ROUTER_SOLICITATION_ADDRESS 32
124 #define DHO_STATIC_ROUTES 33
125 #define DHO_TRAILER_ENCAPSULATION 34
126 #define DHO_ARP_CACHE_TIMEOUT 35
127 #define DHO_IEEE802_3_ENCAPSULATION 36
128 #define DHO_DEFAULT_TCP_TTL 37
129 #define DHO_TCP_KEEPALIVE_INTERVAL 38
130 #define DHO_TCP_KEEPALIVE_GARBAGE 39
131 #define DHO_NIS_DOMAIN 40
132 #define DHO_NIS_SERVERS 41
133 #define DHO_NTP_SERVERS 42
134 #define DHO_VENDOR_ENCAPSULATED_OPTIONS 43
135 #define DHO_NETBIOS_NAME_SERVERS 44
136 #define DHO_NETBIOS_DD_SERVER 45
137 #define DHO_NETBIOS_NODE_TYPE 46
138 #define DHO_NETBIOS_SCOPE 47
139 #define DHO_FONT_SERVERS 48
140 #define DHO_X_DISPLAY_MANAGER 49
141 #define DHO_DHCP_REQUESTED_ADDRESS 50
142 #define DHO_DHCP_LEASE_TIME 51
143 #define DHO_DHCP_OPTION_OVERLOAD 52
144 #define DHO_DHCP_MESSAGE_TYPE 53
145 #define DHO_DHCP_SERVER_IDENTIFIER 54
146 #define DHO_DHCP_PARAMETER_REQUEST_LIST 55
147 #define DHO_DHCP_MESSAGE 56
148 #define DHO_DHCP_MAX_MESSAGE_SIZE 57
149 #define DHO_DHCP_RENEWAL_TIME 58
150 #define DHO_DHCP_REBINDING_TIME 59
151 #define DHO_VENDOR_CLASS_IDENTIFIER 60
152 #define DHO_DHCP_CLIENT_IDENTIFIER 61
153 #define DHO_NWIP_DOMAIN_NAME 62
154 #define DHO_NWIP_SUBOPTIONS 63
155 #define DHO_USER_CLASS 77
156 #define DHO_FQDN 81
157 #define DHO_DHCP_AGENT_OPTIONS 82
158 #define DHO_AUTHENTICATE 90 /* RFC3118, was 210 */
159 #define DHO_CLIENT_LAST_TRANSACTION_TIME 91
160 #define DHO_ASSOCIATED_IP 92
161 #define DHO_PXE_CLIENT_ID 97 /* RFC4578 */
162 #define DHO_V6_ONLY_PREFERRED 108 /* RFC8925 */
163 #define DHO_SUBNET_SELECTION 118 /* RFC3011! */
164 #define DHO_DOMAIN_SEARCH 119 /* RFC3397 */
165 #define DHO_CLASSLESS_STATIC_ROUTES 121 /* RFC3442 */
166 #define DHO_VIVCO_SUBOPTIONS 124
167 #define DHO_VIVSO_SUBOPTIONS 125
168 
169 #define DHO_END 255
170 
171 /* DHCP message types. */
172 #define DHCPDISCOVER 1
173 #define DHCPOFFER 2
174 #define DHCPREQUEST 3
175 #define DHCPDECLINE 4
176 #define DHCPACK 5
177 #define DHCPNAK 6
178 #define DHCPRELEASE 7
179 #define DHCPINFORM 8
180 #define DHCPLEASEQUERY 10
181 #define DHCPLEASEUNASSIGNED 11
182 #define DHCPLEASEUNKNOWN 12
183 #define DHCPLEASEACTIVE 13
184 
185 
186 /* Relay Agent Information option subtypes: */
187 #define RAI_CIRCUIT_ID 1
188 #define RAI_REMOTE_ID 2
189 #define RAI_AGENT_ID 3
190 #define RAI_LINK_SELECT 5
191 /* not yet assigned but next free value */
192 #define RAI_RELAY_PORT 19
193 
194 /* FQDN suboptions: */
195 #define FQDN_NO_CLIENT_UPDATE 1
196 #define FQDN_SERVER_UPDATE 2
197 #define FQDN_ENCODED 3
198 #define FQDN_RCODE1 4
199 #define FQDN_RCODE2 5
200 #define FQDN_HOSTNAME 6
201 #define FQDN_DOMAINNAME 7
202 #define FQDN_FQDN 8
203 #define FQDN_SUBOPTION_COUNT 8
204 
205 /* Enterprise Suboptions: */
206 #define VENDOR_ISC_SUBOPTIONS 2495
207 
208 #endif /* DHCP_H */
char file[DHCP_FILE_LEN]
Definition: dhcp.h:61
char sname[DHCP_SNAME_LEN]
Definition: dhcp.h:60
u_int16_t secs
Definition: dhcp.h:53
u_int8_t hlen
Definition: dhcp.h:50
#define DHCP_SNAME_LEN
Definition: dhcp.h:34
struct in_addr siaddr
Definition: dhcp.h:57
u_int16_t flags
Definition: dhcp.h:54
u_int8_t htype
Definition: dhcp.h:49
unsigned char chaddr[16]
Definition: dhcp.h:59
#define DHCP_MAX_OPTION_LEN
Definition: dhcp.h:44
u_int32_t xid
Definition: dhcp.h:52
struct in_addr yiaddr
Definition: dhcp.h:56
struct in_addr giaddr
Definition: dhcp.h:58
#define DHCP_FILE_LEN
Definition: dhcp.h:35
u_int8_t hops
Definition: dhcp.h:51
struct in_addr ciaddr
Definition: dhcp.h:55
u_int8_t op
Definition: dhcp.h:48
unsigned char options[DHCP_MAX_OPTION_LEN]
Definition: dhcp.h:62