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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 * Offset of Diffserv decimal value to convert it to tos value .
99 #define IPTOS_DSCP_OFFSET 2
102 * Definitions for DiffServ Codepoints as per RFC2474 and RFC5865.
104 #define IPTOS_DSCP_CS0 0x00
105 #define IPTOS_DSCP_CS1 0x20
106 #define IPTOS_DSCP_AF11 0x28
107 #define IPTOS_DSCP_AF12 0x30
108 #define IPTOS_DSCP_AF13 0x38
109 #define IPTOS_DSCP_CS2 0x40
110 #define IPTOS_DSCP_AF21 0x48
111 #define IPTOS_DSCP_AF22 0x50
112 #define IPTOS_DSCP_AF23 0x58
113 #define IPTOS_DSCP_CS3 0x60
114 #define IPTOS_DSCP_AF31 0x68
115 #define IPTOS_DSCP_AF32 0x70
116 #define IPTOS_DSCP_AF33 0x78
117 #define IPTOS_DSCP_CS4 0x80
118 #define IPTOS_DSCP_AF41 0x88
119 #define IPTOS_DSCP_AF42 0x90
120 #define IPTOS_DSCP_AF43 0x98
121 #define IPTOS_DSCP_CS5 0xa0
122 #define IPTOS_DSCP_VA 0xb0
123 #define IPTOS_DSCP_EF 0xb8
124 #define IPTOS_DSCP_CS6 0xc0
125 #define IPTOS_DSCP_CS7 0xe0
128 * ECN (Explicit Congestion Notification) codepoints in RFC3168 mapped to the
129 * lower 2 bits of the TOS field.
131 #define IPTOS_ECN_NOTECT 0x00 /* not-ECT */
132 #define IPTOS_ECN_ECT1 0x01 /* ECN-capable transport (1) */
133 #define IPTOS_ECN_ECT0 0x02 /* ECN-capable transport (0) */
134 #define IPTOS_ECN_CE 0x03 /* congestion experienced */
135 #define IPTOS_ECN_MASK 0x03 /* ECN field mask */
138 * Definitions for options.
140 #define IPOPT_COPIED(o) ((o)&0x80)
141 #define IPOPT_CLASS(o) ((o)&0x60)
142 #define IPOPT_NUMBER(o) ((o)&0x1f)
144 #define IPOPT_CONTROL 0x00
145 #define IPOPT_RESERVED1 0x20
146 #define IPOPT_DEBMEAS 0x40
147 #define IPOPT_RESERVED2 0x60
149 #define IPOPT_EOL 0 /* end of option list */
150 #define IPOPT_NOP 1 /* no operation */
152 #define IPOPT_RR 7 /* record packet route */
153 #define IPOPT_TS 68 /* timestamp */
154 #define IPOPT_SECURITY 130 /* provide s,c,h,tcc */
155 #define IPOPT_LSRR 131 /* loose source route */
156 #define IPOPT_ESO 133 /* extended security */
157 #define IPOPT_CIPSO 134 /* commercial security */
158 #define IPOPT_SATID 136 /* satnet id */
159 #define IPOPT_SSRR 137 /* strict source route */
160 #define IPOPT_RA 148 /* router alert */
163 * Offsets to fields in options other than EOL and NOP.
165 #define IPOPT_OPTVAL 0 /* option ID */
166 #define IPOPT_OLEN 1 /* option length */
167 #define IPOPT_OFFSET 2 /* offset within option */
168 #define IPOPT_MINOFF 4 /* min value of above */
171 * Time stamp option structure.
173 struct ip_timestamp {
174 u_char ipt_code; /* IPOPT_TS */
175 u_char ipt_len; /* size of structure (variable) */
176 u_char ipt_ptr; /* index of current entry */
177 #if BYTE_ORDER == LITTLE_ENDIAN
178 u_char ipt_flg:4, /* flags, see below */
179 ipt_oflw:4; /* overflow counter */
181 #if BYTE_ORDER == BIG_ENDIAN
182 u_char ipt_oflw:4, /* overflow counter */
183 ipt_flg:4; /* flags, see below */
185 union ipt_timestamp {
186 uint32_t ipt_time[1]; /* network format */
188 struct in_addr ipt_addr;
189 uint32_t ipt_time; /* network format */
194 /* Flag bits for ipt_flg. */
195 #define IPOPT_TS_TSONLY 0 /* timestamps only */
196 #define IPOPT_TS_TSANDADDR 1 /* timestamps and addresses */
197 #define IPOPT_TS_PRESPEC 3 /* specified modules only */
199 /* Bits for security (not byte swapped). */
200 #define IPOPT_SECUR_UNCLASS 0x0000
201 #define IPOPT_SECUR_CONFID 0xf135
202 #define IPOPT_SECUR_EFTO 0x789a
203 #define IPOPT_SECUR_MMMM 0xbc4d
204 #define IPOPT_SECUR_RESTR 0xaf13
205 #define IPOPT_SECUR_SECRET 0xd788
206 #define IPOPT_SECUR_TOPSECRET 0x6bc5
209 * Internet implementation parameters.
211 #define MAXTTL 255 /* maximum time to live (seconds) */
212 #define IPDEFTTL 64 /* default ttl, from RFC 1340 */
213 #define IPFRAGTTL 60 /* time to live for frags, slowhz */
214 #define IPTTLDEC 1 /* subtracted when forwarding */
215 #define IP_MSS 576 /* default maximum segment size */
218 * This is the real IPv4 pseudo header, used for computing the TCP and UDP
219 * checksums. For the Internet checksum, struct ipovly can be used instead.
220 * For stronger checksums, the real thing must be used.
223 struct in_addr ippseudo_src; /* source internet address */
224 struct in_addr ippseudo_dst; /* destination internet address */
225 u_char ippseudo_pad; /* pad, must be zero */
226 u_char ippseudo_p; /* protocol */
227 u_short ippseudo_len; /* protocol length */