slirp/src/ip6_icmp.h

   1 /* SPDX-License-Identifier: BSD-3-Clause */
   2 /*
   3  * Copyright (c) 2013
   4  * Guillaume Subiron, Yann Bordenave, Serigne Modou Wagne.
   5  */
   6
   7 #ifndef SLIRP_IP6_ICMP_H
   8 #define SLIRP_IP6_ICMP_H
   9
  10 /*
  11  * Interface Control Message Protocol version 6 Definitions.
  12  * Per RFC 4443, March 2006.
  13  *
  14  * Network Discover Protocol Definitions.
  15  * Per RFC 4861, September 2007.
  16  */
  17
  18 struct icmp6_echo { /* Echo Messages */
  19     uint16_t id;
  20     uint16_t seq_num;
  21 };
  22
  23 union icmp6_error_body {
  24     uint32_t unused;
  25     uint32_t pointer;
  26     uint32_t mtu;
  27 };
  28
  29 /*
  30  * NDP Messages
  31  */
  32 struct ndp_rs {     /* Router Solicitation Message */
  33     uint32_t reserved;
  34 };
  35
  36 struct ndp_ra {     /* Router Advertisement Message */
  37     uint8_t chl;    /* Cur Hop Limit */
  38 #if G_BYTE_ORDER == G_BIG_ENDIAN
  39     uint8_t
  40         M:1,
  41         O:1,
  42         reserved:6;
  43 #else
  44     uint8_t
  45         reserved:6,
  46         O:1,
  47         M:1;
  48 #endif
  49     uint16_t lifetime;      /* Router Lifetime */
  50     uint32_t reach_time;    /* Reachable Time */
  51     uint32_t retrans_time;  /* Retrans Timer */
  52 };
  53
  54 G_STATIC_ASSERT(sizeof(struct ndp_ra) == 12);
  55
  56 struct ndp_ns {     /* Neighbor Solicitation Message */
  57     uint32_t reserved;
  58     struct in6_addr target; /* Target Address */
  59 };
  60
  61 G_STATIC_ASSERT(sizeof(struct ndp_ns) == 20);
  62
  63 struct ndp_na {     /* Neighbor Advertisement Message */
  64 #if G_BYTE_ORDER == G_BIG_ENDIAN
  65     uint32_t
  66         R:1,                /* Router Flag */
  67         S:1,                /* Solicited Flag */
  68         O:1,                /* Override Flag */
  69         reserved_hi:5,
  70         reserved_lo:24;
  71 #else
  72     uint32_t
  73         reserved_hi:5,
  74         O:1,
  75         S:1,
  76         R:1,
  77         reserved_lo:24;
  78 #endif
  79     struct in6_addr target; /* Target Address */
  80 };
  81
  82 G_STATIC_ASSERT(sizeof(struct ndp_na) == 20);
  83
  84 struct ndp_redirect {
  85     uint32_t reserved;
  86     struct in6_addr target; /* Target Address */
  87     struct in6_addr dest;   /* Destination Address */
  88 };
  89
  90 G_STATIC_ASSERT(sizeof(struct ndp_redirect) == 36);
  91
  92 /*
  93  * Structure of an icmpv6 header.
  94  */
  95 struct icmp6 {
  96     uint8_t     icmp6_type;         /* type of message, see below */
  97     uint8_t     icmp6_code;         /* type sub code */
  98     uint16_t    icmp6_cksum;        /* ones complement cksum of struct */
  99     union {
 100         union icmp6_error_body error_body;
 101         struct icmp6_echo echo;
 102         struct ndp_rs ndp_rs;
 103         struct ndp_ra ndp_ra;
 104         struct ndp_ns ndp_ns;
 105         struct ndp_na ndp_na;
 106         struct ndp_redirect ndp_redirect;
 107     } icmp6_body;
 108 #define icmp6_err icmp6_body.error_body
 109 #define icmp6_echo icmp6_body.echo
 110 #define icmp6_nrs icmp6_body.ndp_rs
 111 #define icmp6_nra icmp6_body.ndp_ra
 112 #define icmp6_nns icmp6_body.ndp_ns
 113 #define icmp6_nna icmp6_body.ndp_na
 114 #define icmp6_redirect icmp6_body.ndp_redirect
 115 };
 116
 117 G_STATIC_ASSERT(sizeof(struct icmp6) == 40);
 118
 119 #define ICMP6_MINLEN    4
 120 #define ICMP6_ERROR_MINLEN  8
 121 #define ICMP6_ECHO_MINLEN   8
 122 #define ICMP6_NDP_RS_MINLEN 8
 123 #define ICMP6_NDP_RA_MINLEN 16
 124 #define ICMP6_NDP_NS_MINLEN 24
 125 #define ICMP6_NDP_NA_MINLEN 24
 126 #define ICMP6_NDP_REDIRECT_MINLEN 40
 127
 128 /*
 129  * NDP Options
 130  */
 131 struct ndpopt {
 132     uint8_t     ndpopt_type;                    /* Option type */
 133     uint8_t     ndpopt_len;                     /* /!\ In units of 8 octets */
 134     union {
 135         unsigned char   linklayer_addr[6];      /* Source/Target Link-layer */
 136 #define ndpopt_linklayer ndpopt_body.linklayer_addr
 137         struct prefixinfo {                     /* Prefix Information */
 138             uint8_t     prefix_length;
 139 #if G_BYTE_ORDER == G_BIG_ENDIAN
 140             uint8_t     L:1, A:1, reserved1:6;
 141 #else
 142             uint8_t     reserved1:6, A:1, L:1;
 143 #endif
 144             uint32_t    valid_lt;               /* Valid Lifetime */
 145             uint32_t    pref_lt;                /* Preferred Lifetime */
 146             uint32_t    reserved2;
 147             struct in6_addr prefix;
 148         } SLIRP_PACKED prefixinfo;
 149 #define ndpopt_prefixinfo ndpopt_body.prefixinfo
 150         struct rdnss {
 151             uint16_t reserved;
 152             uint32_t lifetime;
 153             struct in6_addr addr;
 154         } SLIRP_PACKED rdnss;
 155 #define ndpopt_rdnss ndpopt_body.rdnss
 156     } ndpopt_body;
 157 } SLIRP_PACKED;
 158
 159 /* NDP options type */
 160 #define NDPOPT_LINKLAYER_SOURCE     1   /* Source Link-Layer Address */
 161 #define NDPOPT_LINKLAYER_TARGET     2   /* Target Link-Layer Address */
 162 #define NDPOPT_PREFIX_INFO          3   /* Prefix Information */
 163 #define NDPOPT_RDNSS                25  /* Recursive DNS Server Address */
 164
 165 /* NDP options size, in octets. */
 166 #define NDPOPT_LINKLAYER_LEN    8
 167 #define NDPOPT_PREFIXINFO_LEN   32
 168 #define NDPOPT_RDNSS_LEN        24
 169
 170 /*
 171  * Definition of type and code field values.
 172  * Per https://www.iana.org/assignments/icmpv6-parameters/icmpv6-parameters.xml
 173  * Last Updated 2012-11-12
 174  */
 175
 176 /* Errors */
 177 #define ICMP6_UNREACH   1   /* Destination Unreachable */
 178 #define     ICMP6_UNREACH_NO_ROUTE      0   /* no route to dest */
 179 #define     ICMP6_UNREACH_DEST_PROHIB   1   /* com with dest prohibited */
 180 #define     ICMP6_UNREACH_SCOPE         2   /* beyond scope of src addr */
 181 #define     ICMP6_UNREACH_ADDRESS       3   /* address unreachable */
 182 #define     ICMP6_UNREACH_PORT          4   /* port unreachable */
 183 #define     ICMP6_UNREACH_SRC_FAIL      5   /* src addr failed */
 184 #define     ICMP6_UNREACH_REJECT_ROUTE  6   /* reject route to dest */
 185 #define     ICMP6_UNREACH_SRC_HDR_ERROR 7   /* error in src routing header */
 186 #define ICMP6_TOOBIG    2   /* Packet Too Big */
 187 #define ICMP6_TIMXCEED  3   /* Time Exceeded */
 188 #define     ICMP6_TIMXCEED_INTRANS      0   /* hop limit exceeded in transit */
 189 #define     ICMP6_TIMXCEED_REASS        1   /* ttl=0 in reass */
 190 #define ICMP6_PARAMPROB 4   /* Parameter Problem */
 191 #define     ICMP6_PARAMPROB_HDR_FIELD   0   /* err header field */
 192 #define     ICMP6_PARAMPROB_NXTHDR_TYPE 1   /* unrecognized Next Header type */
 193 #define     ICMP6_PARAMPROB_IPV6_OPT    2   /* unrecognized IPv6 option */
 194
 195 /* Informational Messages */
 196 #define ICMP6_ECHO_REQUEST      128 /* Echo Request */
 197 #define ICMP6_ECHO_REPLY        129 /* Echo Reply */
 198 #define ICMP6_NDP_RS            133 /* Router Solicitation (NDP) */
 199 #define ICMP6_NDP_RA            134 /* Router Advertisement (NDP) */
 200 #define ICMP6_NDP_NS            135 /* Neighbor Solicitation (NDP) */
 201 #define ICMP6_NDP_NA            136 /* Neighbor Advertisement (NDP) */
 202 #define ICMP6_NDP_REDIRECT      137 /* Redirect Message (NDP) */
 203
 204 /*
 205  * Router Configuration Variables (rfc4861#section-6)
 206  */
 207 #define NDP_IsRouter                1
 208 #define NDP_AdvSendAdvertisements   1
 209 #define NDP_MaxRtrAdvInterval       600000
 210 #define NDP_MinRtrAdvInterval       ((NDP_MaxRtrAdvInterval >= 9) ? \
 211                                         NDP_MaxRtrAdvInterval / 3 : \
 212                                         NDP_MaxRtrAdvInterval)
 213 #define NDP_AdvManagedFlag          0
 214 #define NDP_AdvOtherConfigFlag      0
 215 #define NDP_AdvLinkMTU              0
 216 #define NDP_AdvReachableTime        0
 217 #define NDP_AdvRetransTime          0
 218 #define NDP_AdvCurHopLimit          64
 219 #define NDP_AdvDefaultLifetime      ((3 * NDP_MaxRtrAdvInterval) / 1000)
 220 #define NDP_AdvValidLifetime        86400
 221 #define NDP_AdvOnLinkFlag           1
 222 #define NDP_AdvPrefLifetime         14400
 223 #define NDP_AdvAutonomousFlag       1
 224
 225 void icmp6_init(Slirp *slirp);
 226 void icmp6_cleanup(Slirp *slirp);
 227 void icmp6_input(struct mbuf *);
 228 void icmp6_send_error(struct mbuf *m, uint8_t type, uint8_t code);
 229 void ndp_send_ra(Slirp *slirp);
 230 void ndp_send_ns(Slirp *slirp, struct in6_addr addr);
 231
 232 #endif