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 #include <glib.h>
  37
  38 #if G_BYTE_ORDER == G_BIG_ENDIAN
  39 # undef NTOHL
  40 # undef NTOHS
  41 # undef HTONL
  42 # undef HTONS
  43 # define NTOHL(d)
  44 # define NTOHS(d)
  45 # define HTONL(d)
  46 # define HTONS(d)
  47 #else
  48 # ifndef NTOHL
  49 #  define NTOHL(d) ((d) = ntohl((d)))
  50 # endif
  51 # ifndef NTOHS
  52 #  define NTOHS(d) ((d) = ntohs((uint16_t)(d)))
  53 # endif
  54 # ifndef HTONL
  55 #  define HTONL(d) ((d) = htonl((d)))
  56 # endif
  57 # ifndef HTONS
  58 #  define HTONS(d) ((d) = htons((uint16_t)(d)))
  59 # endif
  60 #endif
  61
  62 typedef uint32_t n_long;                 /* long as received from the net */
  63
  64 /*
  65  * Definitions for internet protocol version 4.
  66  * Per RFC 791, September 1981.
  67  */
  68 #define IPVERSION       4
  69
  70 /*
  71  * Structure of an internet header, naked of options.
  72  */
  73 struct ip {
  74 #if G_BYTE_ORDER == G_BIG_ENDIAN
  75         uint8_t ip_v:4,                 /* version */
  76                 ip_hl:4;                /* header length */
  77 #else
  78         uint8_t ip_hl:4,                /* header length */
  79                 ip_v:4;                 /* version */
  80 #endif
  81         uint8_t         ip_tos;                 /* type of service */
  82         uint16_t        ip_len;                 /* total length */
  83         uint16_t        ip_id;                  /* identification */
  84         uint16_t        ip_off;                 /* fragment offset field */
  85 #define IP_DF 0x4000                    /* don't fragment flag */
  86 #define IP_MF 0x2000                    /* more fragments flag */
  87 #define IP_OFFMASK 0x1fff               /* mask for fragmenting bits */
  88         uint8_t ip_ttl;                 /* time to live */
  89         uint8_t ip_p;                   /* protocol */
  90         uint16_t        ip_sum;                 /* checksum */
  91         struct  in_addr ip_src,ip_dst;  /* source and dest address */
  92 } SLIRP_PACKED;
  93
  94 #define IP_MAXPACKET    65535           /* maximum packet size */
  95
  96 /*
  97  * Definitions for IP type of service (ip_tos)
  98  */
  99 #define IPTOS_LOWDELAY          0x10
 100 #define IPTOS_THROUGHPUT        0x08
 101 #define IPTOS_RELIABILITY       0x04
 102
 103 /*
 104  * Definitions for options.
 105  */
 106 #define IPOPT_COPIED(o)         ((o)&0x80)
 107 #define IPOPT_CLASS(o)          ((o)&0x60)
 108 #define IPOPT_NUMBER(o)         ((o)&0x1f)
 109
 110 #define IPOPT_CONTROL           0x00
 111 #define IPOPT_RESERVED1         0x20
 112 #define IPOPT_DEBMEAS           0x40
 113 #define IPOPT_RESERVED2         0x60
 114
 115 #define IPOPT_EOL               0               /* end of option list */
 116 #define IPOPT_NOP               1               /* no operation */
 117
 118 #define IPOPT_RR                7               /* record packet route */
 119 #define IPOPT_TS                68              /* timestamp */
 120 #define IPOPT_SECURITY          130             /* provide s,c,h,tcc */
 121 #define IPOPT_LSRR              131             /* loose source route */
 122 #define IPOPT_SATID             136             /* satnet id */
 123 #define IPOPT_SSRR              137             /* strict source route */
 124
 125 /*
 126  * Offsets to fields in options other than EOL and NOP.
 127  */
 128 #define IPOPT_OPTVAL            0               /* option ID */
 129 #define IPOPT_OLEN              1               /* option length */
 130 #define IPOPT_OFFSET            2               /* offset within option */
 131 #define IPOPT_MINOFF            4               /* min value of above */
 132
 133 /*
 134  * Time stamp option structure.
 135  */
 136 struct  ip_timestamp {
 137         uint8_t ipt_code;               /* IPOPT_TS */
 138         uint8_t ipt_len;                /* size of structure (variable) */
 139         uint8_t ipt_ptr;                /* index of current entry */
 140 #if G_BYTE_ORDER == G_BIG_ENDIAN
 141         uint8_t ipt_oflw:4,             /* overflow counter */
 142                 ipt_flg:4;              /* flags, see below */
 143 #else
 144         uint8_t ipt_flg:4,              /* flags, see below */
 145                 ipt_oflw:4;             /* overflow counter */
 146 #endif
 147         union ipt_timestamp {
 148                 n_long  ipt_time[1];
 149                 struct  ipt_ta {
 150                         struct in_addr ipt_addr;
 151                         n_long ipt_time;
 152                 } ipt_ta[1];
 153         } ipt_timestamp;
 154 } SLIRP_PACKED;
 155
 156 /* flag bits for ipt_flg */
 157 #define IPOPT_TS_TSONLY         0               /* timestamps only */
 158 #define IPOPT_TS_TSANDADDR      1               /* timestamps and addresses */
 159 #define IPOPT_TS_PRESPEC        3               /* specified modules only */
 160
 161 /* bits for security (not byte swapped) */
 162 #define IPOPT_SECUR_UNCLASS     0x0000
 163 #define IPOPT_SECUR_CONFID      0xf135
 164 #define IPOPT_SECUR_EFTO        0x789a
 165 #define IPOPT_SECUR_MMMM        0xbc4d
 166 #define IPOPT_SECUR_RESTR       0xaf13
 167 #define IPOPT_SECUR_SECRET      0xd788
 168 #define IPOPT_SECUR_TOPSECRET   0x6bc5
 169
 170 /*
 171  * Internet implementation parameters.
 172  */
 173 #define MAXTTL          255             /* maximum time to live (seconds) */
 174 #define IPDEFTTL        64              /* default ttl, from RFC 1340 */
 175 #define IPFRAGTTL       60              /* time to live for frags, slowhz */
 176 #define IPTTLDEC        1               /* subtracted when forwarding */
 177
 178 #define IP_MSS          576             /* default maximum segment size */
 179
 180 #if GLIB_SIZEOF_VOID_P == 4
 181 struct mbuf_ptr {
 182         struct mbuf *mptr;
 183         uint32_t dummy;
 184 } SLIRP_PACKED;
 185 #else
 186 struct mbuf_ptr {
 187         struct mbuf *mptr;
 188 } SLIRP_PACKED;
 189 #endif
 190 struct qlink {
 191         void *next, *prev;
 192 };
 193
 194 /*
 195  * Overlay for ip header used by other protocols (tcp, udp).
 196  */
 197 struct ipovly {
 198         struct mbuf_ptr ih_mbuf;        /* backpointer to mbuf */
 199         uint8_t ih_x1;                  /* (unused) */
 200         uint8_t ih_pr;                  /* protocol */
 201         uint16_t        ih_len;                 /* protocol length */
 202         struct  in_addr ih_src;         /* source internet address */
 203         struct  in_addr ih_dst;         /* destination internet address */
 204 } SLIRP_PACKED;
 205
 206 /*
 207  * Ip reassembly queue structure.  Each fragment
 208  * being reassembled is attached to one of these structures.
 209  * They are timed out after ipq_ttl drops to 0, and may also
 210  * be reclaimed if memory becomes tight.
 211  * size 28 bytes
 212  */
 213 struct ipq {
 214         struct qlink frag_link;                 /* to ip headers of fragments */
 215         struct qlink ip_link;                           /* to other reass headers */
 216         uint8_t ipq_ttl;                /* time for reass q to live */
 217         uint8_t ipq_p;                  /* protocol of this fragment */
 218         uint16_t        ipq_id;                 /* sequence id for reassembly */
 219         struct  in_addr ipq_src,ipq_dst;
 220 };
 221
 222 /*
 223  * Ip header, when holding a fragment.
 224  *
 225  * Note: ipf_link must be at same offset as frag_link above
 226  */
 227 struct  ipasfrag {
 228         struct qlink ipf_link;
 229         struct ip ipf_ip;
 230 };
 231
 232 G_STATIC_ASSERT(offsetof(struct ipq, frag_link) ==
 233                 offsetof(struct ipasfrag, ipf_link));
 234
 235 #define ipf_off      ipf_ip.ip_off
 236 #define ipf_tos      ipf_ip.ip_tos
 237 #define ipf_len      ipf_ip.ip_len
 238 #define ipf_next     ipf_link.next
 239 #define ipf_prev     ipf_link.prev
 240
 241 #endif