slirp/ip.h

   1 /*
   2  * Copyright (c) 1982, 1986, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  *      @(#)ip.h        8.1 (Berkeley) 6/10/93
  30  * ip.h,v 1.3 1994/08/21 05:27:30 paul Exp
  31  */
  32
  33 #ifndef _IP_H_
  34 #define _IP_H_
  35
  36 #ifdef HOST_WORDS_BIGENDIAN
  37 # ifndef NTOHL
  38 #  define NTOHL(d)
  39 # endif
  40 # ifndef NTOHS
  41 #  define NTOHS(d)
  42 # endif
  43 # ifndef HTONL
  44 #  define HTONL(d)
  45 # endif
  46 # ifndef HTONS
  47 #  define HTONS(d)
  48 # endif
  49 #else
  50 # ifndef NTOHL
  51 #  define NTOHL(d) ((d) = ntohl((d)))
  52 # endif
  53 # ifndef NTOHS
  54 #  define NTOHS(d) ((d) = ntohs((u_int16_t)(d)))
  55 # endif
  56 # ifndef HTONL
  57 #  define HTONL(d) ((d) = htonl((d)))
  58 # endif
  59 # ifndef HTONS
  60 #  define HTONS(d) ((d) = htons((u_int16_t)(d)))
  61 # endif
  62 #endif
  63
  64 typedef u_int32_t n_long;                 /* long as received from the net */
  65
  66 /*
  67  * Definitions for internet protocol version 4.
  68  * Per RFC 791, September 1981.
  69  */
  70 #define IPVERSION       4
  71
  72 /*
  73  * Structure of an internet header, naked of options.
  74  */
  75 struct ip {
  76 #ifdef HOST_WORDS_BIGENDIAN
  77         u_int ip_v:4,                   /* version */
  78                 ip_hl:4;                /* header length */
  79 #else
  80         u_int ip_hl:4,          /* header length */
  81                 ip_v:4;                 /* version */
  82 #endif
  83         u_int8_t ip_tos;                        /* type of service */
  84         u_int16_t       ip_len;                 /* total length */
  85         u_int16_t       ip_id;                  /* identification */
  86         u_int16_t       ip_off;                 /* fragment offset field */
  87 #define IP_DF 0x4000                    /* don't fragment flag */
  88 #define IP_MF 0x2000                    /* more fragments flag */
  89 #define IP_OFFMASK 0x1fff               /* mask for fragmenting bits */
  90         u_int8_t ip_ttl;                        /* time to live */
  91         u_int8_t ip_p;                  /* protocol */
  92         u_int16_t       ip_sum;                 /* checksum */
  93         struct  in_addr ip_src,ip_dst;  /* source and dest address */
  94 } __attribute__((packed));
  95
  96 #define IP_MAXPACKET    65535           /* maximum packet size */
  97
  98 /*
  99  * Definitions for IP type of service (ip_tos)
 100  */
 101 #define IPTOS_LOWDELAY          0x10
 102 #define IPTOS_THROUGHPUT        0x08
 103 #define IPTOS_RELIABILITY       0x04
 104
 105 /*
 106  * Definitions for options.
 107  */
 108 #define IPOPT_COPIED(o)         ((o)&0x80)
 109 #define IPOPT_CLASS(o)          ((o)&0x60)
 110 #define IPOPT_NUMBER(o)         ((o)&0x1f)
 111
 112 #define IPOPT_CONTROL           0x00
 113 #define IPOPT_RESERVED1         0x20
 114 #define IPOPT_DEBMEAS           0x40
 115 #define IPOPT_RESERVED2         0x60
 116
 117 #define IPOPT_EOL               0               /* end of option list */
 118 #define IPOPT_NOP               1               /* no operation */
 119
 120 #define IPOPT_RR                7               /* record packet route */
 121 #define IPOPT_TS                68              /* timestamp */
 122 #define IPOPT_SECURITY          130             /* provide s,c,h,tcc */
 123 #define IPOPT_LSRR              131             /* loose source route */
 124 #define IPOPT_SATID             136             /* satnet id */
 125 #define IPOPT_SSRR              137             /* strict source route */
 126
 127 /*
 128  * Offsets to fields in options other than EOL and NOP.
 129  */
 130 #define IPOPT_OPTVAL            0               /* option ID */
 131 #define IPOPT_OLEN              1               /* option length */
 132 #define IPOPT_OFFSET            2               /* offset within option */
 133 #define IPOPT_MINOFF            4               /* min value of above */
 134
 135 /*
 136  * Time stamp option structure.
 137  */
 138 struct  ip_timestamp {
 139         u_int8_t        ipt_code;               /* IPOPT_TS */
 140         u_int8_t        ipt_len;                /* size of structure (variable) */
 141         u_int8_t        ipt_ptr;                /* index of current entry */
 142 #ifdef HOST_WORDS_BIGENDIAN
 143         u_int   ipt_oflw:4,             /* overflow counter */
 144                 ipt_flg:4;              /* flags, see below */
 145 #else
 146         u_int   ipt_flg:4,              /* flags, see below */
 147                 ipt_oflw:4;             /* overflow counter */
 148 #endif
 149         union ipt_timestamp {
 150                 n_long  ipt_time[1];
 151                 struct  ipt_ta {
 152                         struct in_addr ipt_addr;
 153                         n_long ipt_time;
 154                 } ipt_ta[1];
 155         } ipt_timestamp;
 156 } __attribute__((packed));
 157
 158 /* flag bits for ipt_flg */
 159 #define IPOPT_TS_TSONLY         0               /* timestamps only */
 160 #define IPOPT_TS_TSANDADDR      1               /* timestamps and addresses */
 161 #define IPOPT_TS_PRESPEC        3               /* specified modules only */
 162
 163 /* bits for security (not byte swapped) */
 164 #define IPOPT_SECUR_UNCLASS     0x0000
 165 #define IPOPT_SECUR_CONFID      0xf135
 166 #define IPOPT_SECUR_EFTO        0x789a
 167 #define IPOPT_SECUR_MMMM        0xbc4d
 168 #define IPOPT_SECUR_RESTR       0xaf13
 169 #define IPOPT_SECUR_SECRET      0xd788
 170 #define IPOPT_SECUR_TOPSECRET   0x6bc5
 171
 172 /*
 173  * Internet implementation parameters.
 174  */
 175 #define MAXTTL          255             /* maximum time to live (seconds) */
 176 #define IPDEFTTL        64              /* default ttl, from RFC 1340 */
 177 #define IPFRAGTTL       60              /* time to live for frags, slowhz */
 178 #define IPTTLDEC        1               /* subtracted when forwarding */
 179
 180 #define IP_MSS          576             /* default maximum segment size */
 181
 182 #if SIZEOF_CHAR_P == 4
 183 struct mbuf_ptr {
 184         struct mbuf *mptr;
 185         uint32_t dummy;
 186 } __attribute__((packed));
 187 #else
 188 struct mbuf_ptr {
 189         struct mbuf *mptr;
 190 } __attribute__((packed));
 191 #endif
 192 struct qlink {
 193         void *next, *prev;
 194 };
 195
 196 /*
 197  * Overlay for ip header used by other protocols (tcp, udp).
 198  */
 199 struct ipovly {
 200         struct mbuf_ptr ih_mbuf;        /* backpointer to mbuf */
 201         u_int8_t        ih_x1;                  /* (unused) */
 202         u_int8_t        ih_pr;                  /* protocol */
 203         u_int16_t       ih_len;                 /* protocol length */
 204         struct  in_addr ih_src;         /* source internet address */
 205         struct  in_addr ih_dst;         /* destination internet address */
 206 } __attribute__((packed));
 207
 208 /*
 209  * Ip reassembly queue structure.  Each fragment
 210  * being reassembled is attached to one of these structures.
 211  * They are timed out after ipq_ttl drops to 0, and may also
 212  * be reclaimed if memory becomes tight.
 213  * size 28 bytes
 214  */
 215 struct ipq {
 216         struct qlink frag_link;                 /* to ip headers of fragments */
 217         struct qlink ip_link;                           /* to other reass headers */
 218         u_int8_t        ipq_ttl;                /* time for reass q to live */
 219         u_int8_t        ipq_p;                  /* protocol of this fragment */
 220         u_int16_t       ipq_id;                 /* sequence id for reassembly */
 221         struct  in_addr ipq_src,ipq_dst;
 222 } __attribute__((packed));
 223
 224 /*
 225  * Ip header, when holding a fragment.
 226  *
 227  * Note: ipf_link must be at same offset as frag_link above
 228  */
 229 struct  ipasfrag {
 230         struct qlink ipf_link;
 231         struct ip ipf_ip;
 232 } __attribute__((packed));
 233
 234 #define ipf_off      ipf_ip.ip_off
 235 #define ipf_tos      ipf_ip.ip_tos
 236 #define ipf_len      ipf_ip.ip_len
 237 #define ipf_next     ipf_link.next
 238 #define ipf_prev     ipf_link.prev
 239
 240 /*
 241  * Structure stored in mbuf in inpcb.ip_options
 242  * and passed to ip_output when ip options are in use.
 243  * The actual length of the options (including ipopt_dst)
 244  * is in m_len.
 245  */
 246 #define MAX_IPOPTLEN    40
 247
 248 struct ipoption {
 249         struct  in_addr ipopt_dst;      /* first-hop dst if source routed */
 250         int8_t  ipopt_list[MAX_IPOPTLEN];       /* options proper */
 251 } __attribute__((packed));
 252
 253 #endif