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32 * @(#)ip.h 8.2 (Berkeley) 6/1/94
36 #ifndef _NETINET_IP_H_
37 #define _NETINET_IP_H_
39 #include <sys/cdefs.h>
42 * Definitions for internet protocol version 4.
44 * Per RFC 791, September 1981.
49 * Structure of an internet header, naked of options.
52 #if BYTE_ORDER == LITTLE_ENDIAN
53 u_char ip_hl:4, /* header length */
56 #if BYTE_ORDER == BIG_ENDIAN
57 u_char ip_v:4, /* version */
58 ip_hl:4; /* header length */
60 u_char ip_tos; /* type of service */
61 u_short ip_len; /* total length */
62 u_short ip_id; /* identification */
63 u_short ip_off; /* fragment offset field */
64 #define IP_RF 0x8000 /* reserved fragment flag */
65 #define IP_DF 0x4000 /* dont fragment flag */
66 #define IP_MF 0x2000 /* more fragments flag */
67 #define IP_OFFMASK 0x1fff /* mask for fragmenting bits */
68 u_char ip_ttl; /* time to live */
69 u_char ip_p; /* protocol */
70 u_short ip_sum; /* checksum */
71 struct in_addr ip_src,ip_dst; /* source and dest address */
72 } __packed __aligned(2);
74 #define IP_MAXPACKET 65535 /* maximum packet size */
77 * Definitions for IP type of service (ip_tos).
79 #define IPTOS_LOWDELAY 0x10
80 #define IPTOS_THROUGHPUT 0x08
81 #define IPTOS_RELIABILITY 0x04
82 #define IPTOS_MINCOST 0x02
85 * Definitions for IP precedence (also in ip_tos) (deprecated).
87 #define IPTOS_PREC_NETCONTROL IPTOS_DSCP_CS7
88 #define IPTOS_PREC_INTERNETCONTROL IPTOS_DSCP_CS6
89 #define IPTOS_PREC_CRITIC_ECP IPTOS_DSCP_CS5
90 #define IPTOS_PREC_FLASHOVERRIDE IPTOS_DSCP_CS4
91 #define IPTOS_PREC_FLASH IPTOS_DSCP_CS3
92 #define IPTOS_PREC_IMMEDIATE IPTOS_DSCP_CS2
93 #define IPTOS_PREC_PRIORITY IPTOS_DSCP_CS1
94 #define IPTOS_PREC_ROUTINE IPTOS_DSCP_CS0
97 * Definitions for DiffServ Codepoints as per RFC2474 and RFC5865.
99 #define IPTOS_DSCP_CS0 0x00
100 #define IPTOS_DSCP_CS1 0x20
101 #define IPTOS_DSCP_AF11 0x28
102 #define IPTOS_DSCP_AF12 0x30
103 #define IPTOS_DSCP_AF13 0x38
104 #define IPTOS_DSCP_CS2 0x40
105 #define IPTOS_DSCP_AF21 0x48
106 #define IPTOS_DSCP_AF22 0x50
107 #define IPTOS_DSCP_AF23 0x58
108 #define IPTOS_DSCP_CS3 0x60
109 #define IPTOS_DSCP_AF31 0x68
110 #define IPTOS_DSCP_AF32 0x70
111 #define IPTOS_DSCP_AF33 0x78
112 #define IPTOS_DSCP_CS4 0x80
113 #define IPTOS_DSCP_AF41 0x88
114 #define IPTOS_DSCP_AF42 0x90
115 #define IPTOS_DSCP_AF43 0x98
116 #define IPTOS_DSCP_CS5 0xa0
117 #define IPTOS_DSCP_VA 0xb0
118 #define IPTOS_DSCP_EF 0xb8
119 #define IPTOS_DSCP_CS6 0xc0
120 #define IPTOS_DSCP_CS7 0xe0
123 * ECN (Explicit Congestion Notification) codepoints in RFC3168 mapped to the
124 * lower 2 bits of the TOS field.
126 #define IPTOS_ECN_NOTECT 0x00 /* not-ECT */
127 #define IPTOS_ECN_ECT1 0x01 /* ECN-capable transport (1) */
128 #define IPTOS_ECN_ECT0 0x02 /* ECN-capable transport (0) */
129 #define IPTOS_ECN_CE 0x03 /* congestion experienced */
130 #define IPTOS_ECN_MASK 0x03 /* ECN field mask */
133 * Definitions for options.
135 #define IPOPT_COPIED(o) ((o)&0x80)
136 #define IPOPT_CLASS(o) ((o)&0x60)
137 #define IPOPT_NUMBER(o) ((o)&0x1f)
139 #define IPOPT_CONTROL 0x00
140 #define IPOPT_RESERVED1 0x20
141 #define IPOPT_DEBMEAS 0x40
142 #define IPOPT_RESERVED2 0x60
144 #define IPOPT_EOL 0 /* end of option list */
145 #define IPOPT_NOP 1 /* no operation */
147 #define IPOPT_RR 7 /* record packet route */
148 #define IPOPT_TS 68 /* timestamp */
149 #define IPOPT_SECURITY 130 /* provide s,c,h,tcc */
150 #define IPOPT_LSRR 131 /* loose source route */
151 #define IPOPT_ESO 133 /* extended security */
152 #define IPOPT_CIPSO 134 /* commercial security */
153 #define IPOPT_SATID 136 /* satnet id */
154 #define IPOPT_SSRR 137 /* strict source route */
155 #define IPOPT_RA 148 /* router alert */
158 * Offsets to fields in options other than EOL and NOP.
160 #define IPOPT_OPTVAL 0 /* option ID */
161 #define IPOPT_OLEN 1 /* option length */
162 #define IPOPT_OFFSET 2 /* offset within option */
163 #define IPOPT_MINOFF 4 /* min value of above */
166 * Time stamp option structure.
168 struct ip_timestamp {
169 u_char ipt_code; /* IPOPT_TS */
170 u_char ipt_len; /* size of structure (variable) */
171 u_char ipt_ptr; /* index of current entry */
172 #if BYTE_ORDER == LITTLE_ENDIAN
173 u_char ipt_flg:4, /* flags, see below */
174 ipt_oflw:4; /* overflow counter */
176 #if BYTE_ORDER == BIG_ENDIAN
177 u_char ipt_oflw:4, /* overflow counter */
178 ipt_flg:4; /* flags, see below */
180 union ipt_timestamp {
181 uint32_t ipt_time[1]; /* network format */
183 struct in_addr ipt_addr;
184 uint32_t ipt_time; /* network format */
189 /* Flag bits for ipt_flg. */
190 #define IPOPT_TS_TSONLY 0 /* timestamps only */
191 #define IPOPT_TS_TSANDADDR 1 /* timestamps and addresses */
192 #define IPOPT_TS_PRESPEC 3 /* specified modules only */
194 /* Bits for security (not byte swapped). */
195 #define IPOPT_SECUR_UNCLASS 0x0000
196 #define IPOPT_SECUR_CONFID 0xf135
197 #define IPOPT_SECUR_EFTO 0x789a
198 #define IPOPT_SECUR_MMMM 0xbc4d
199 #define IPOPT_SECUR_RESTR 0xaf13
200 #define IPOPT_SECUR_SECRET 0xd788
201 #define IPOPT_SECUR_TOPSECRET 0x6bc5
204 * Internet implementation parameters.
206 #define MAXTTL 255 /* maximum time to live (seconds) */
207 #define IPDEFTTL 64 /* default ttl, from RFC 1340 */
208 #define IPFRAGTTL 60 /* time to live for frags, slowhz */
209 #define IPTTLDEC 1 /* subtracted when forwarding */
210 #define IP_MSS 576 /* default maximum segment size */
213 * This is the real IPv4 pseudo header, used for computing the TCP and UDP
214 * checksums. For the Internet checksum, struct ipovly can be used instead.
215 * For stronger checksums, the real thing must be used.
218 struct in_addr ippseudo_src; /* source internet address */
219 struct in_addr ippseudo_dst; /* destination internet address */
220 u_char ippseudo_pad; /* pad, must be zero */
221 u_char ippseudo_p; /* protocol */
222 u_short ippseudo_len; /* protocol length */