amt.h

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2 /*
   3  * Copyright (c) 2021 Taehee Yoo <ap420073@gmail.com>
   4  */
   5 #ifndef _NET_AMT_H_
   6 #define _NET_AMT_H_
   7
   8 #include <linux/siphash.h>
   9 #include <linux/jhash.h>
  10 #include <linux/netdevice.h>
  11 #include <net/gro_cells.h>
  12 #include <net/rtnetlink.h>
  13
  14 enum amt_msg_type {
  15         AMT_MSG_DISCOVERY = 1,
  16         AMT_MSG_ADVERTISEMENT,
  17         AMT_MSG_REQUEST,
  18         AMT_MSG_MEMBERSHIP_QUERY,
  19         AMT_MSG_MEMBERSHIP_UPDATE,
  20         AMT_MSG_MULTICAST_DATA,
  21         AMT_MSG_TEARDOWN,
  22         __AMT_MSG_MAX,
  23 };
  24
  25 #define AMT_MSG_MAX (__AMT_MSG_MAX - 1)
  26
  27 enum amt_ops {
  28         /* A*B */
  29         AMT_OPS_INT,
  30         /* A+B */
  31         AMT_OPS_UNI,
  32         /* A-B */
  33         AMT_OPS_SUB,
  34         /* B-A */
  35         AMT_OPS_SUB_REV,
  36         __AMT_OPS_MAX,
  37 };
  38
  39 #define AMT_OPS_MAX (__AMT_OPS_MAX - 1)
  40
  41 enum amt_filter {
  42         AMT_FILTER_FWD,
  43         AMT_FILTER_D_FWD,
  44         AMT_FILTER_FWD_NEW,
  45         AMT_FILTER_D_FWD_NEW,
  46         AMT_FILTER_ALL,
  47         AMT_FILTER_NONE_NEW,
  48         AMT_FILTER_BOTH,
  49         AMT_FILTER_BOTH_NEW,
  50         __AMT_FILTER_MAX,
  51 };
  52
  53 #define AMT_FILTER_MAX (__AMT_FILTER_MAX - 1)
  54
  55 enum amt_act {
  56         AMT_ACT_GMI,
  57         AMT_ACT_GMI_ZERO,
  58         AMT_ACT_GT,
  59         AMT_ACT_STATUS_FWD_NEW,
  60         AMT_ACT_STATUS_D_FWD_NEW,
  61         AMT_ACT_STATUS_NONE_NEW,
  62         __AMT_ACT_MAX,
  63 };
  64
  65 #define AMT_ACT_MAX (__AMT_ACT_MAX - 1)
  66
  67 enum amt_status {
  68         AMT_STATUS_INIT,
  69         AMT_STATUS_SENT_DISCOVERY,
  70         AMT_STATUS_RECEIVED_DISCOVERY,
  71         AMT_STATUS_SENT_ADVERTISEMENT,
  72         AMT_STATUS_RECEIVED_ADVERTISEMENT,
  73         AMT_STATUS_SENT_REQUEST,
  74         AMT_STATUS_RECEIVED_REQUEST,
  75         AMT_STATUS_SENT_QUERY,
  76         AMT_STATUS_RECEIVED_QUERY,
  77         AMT_STATUS_SENT_UPDATE,
  78         AMT_STATUS_RECEIVED_UPDATE,
  79         __AMT_STATUS_MAX,
  80 };
  81
  82 #define AMT_STATUS_MAX (__AMT_STATUS_MAX - 1)
  83
  84 /* Gateway events only */
  85 enum amt_event {
  86         AMT_EVENT_NONE,
  87         AMT_EVENT_RECEIVE,
  88         AMT_EVENT_SEND_DISCOVERY,
  89         AMT_EVENT_SEND_REQUEST,
  90         __AMT_EVENT_MAX,
  91 };
  92
  93 struct amt_header {
  94 #if defined(__LITTLE_ENDIAN_BITFIELD)
  95         u8 type:4,
  96            version:4;
  97 #elif defined(__BIG_ENDIAN_BITFIELD)
  98         u8 version:4,
  99            type:4;
 100 #else
 101 #error  "Please fix <asm/byteorder.h>"
 102 #endif
 103 } __packed;
 104
 105 struct amt_header_discovery {
 106 #if defined(__LITTLE_ENDIAN_BITFIELD)
 107         u32     type:4,
 108                 version:4,
 109                 reserved:24;
 110 #elif defined(__BIG_ENDIAN_BITFIELD)
 111         u32     version:4,
 112                 type:4,
 113                 reserved:24;
 114 #else
 115 #error  "Please fix <asm/byteorder.h>"
 116 #endif
 117         __be32  nonce;
 118 } __packed;
 119
 120 struct amt_header_advertisement {
 121 #if defined(__LITTLE_ENDIAN_BITFIELD)
 122         u32     type:4,
 123                 version:4,
 124                 reserved:24;
 125 #elif defined(__BIG_ENDIAN_BITFIELD)
 126         u32     version:4,
 127                 type:4,
 128                 reserved:24;
 129 #else
 130 #error  "Please fix <asm/byteorder.h>"
 131 #endif
 132         __be32  nonce;
 133         __be32  ip4;
 134 } __packed;
 135
 136 struct amt_header_request {
 137 #if defined(__LITTLE_ENDIAN_BITFIELD)
 138         u32     type:4,
 139                 version:4,
 140                 reserved1:7,
 141                 p:1,
 142                 reserved2:16;
 143 #elif defined(__BIG_ENDIAN_BITFIELD)
 144         u32     version:4,
 145                 type:4,
 146                 p:1,
 147                 reserved1:7,
 148                 reserved2:16;
 149 #else
 150 #error  "Please fix <asm/byteorder.h>"
 151 #endif
 152         __be32  nonce;
 153 } __packed;
 154
 155 struct amt_header_membership_query {
 156 #if defined(__LITTLE_ENDIAN_BITFIELD)
 157         u64     type:4,
 158                 version:4,
 159                 reserved:6,
 160                 l:1,
 161                 g:1,
 162                 response_mac:48;
 163 #elif defined(__BIG_ENDIAN_BITFIELD)
 164         u64     version:4,
 165                 type:4,
 166                 g:1,
 167                 l:1,
 168                 reserved:6,
 169                 response_mac:48;
 170 #else
 171 #error  "Please fix <asm/byteorder.h>"
 172 #endif
 173         __be32  nonce;
 174 } __packed;
 175
 176 struct amt_header_membership_update {
 177 #if defined(__LITTLE_ENDIAN_BITFIELD)
 178         u64     type:4,
 179                 version:4,
 180                 reserved:8,
 181                 response_mac:48;
 182 #elif defined(__BIG_ENDIAN_BITFIELD)
 183         u64     version:4,
 184                 type:4,
 185                 reserved:8,
 186                 response_mac:48;
 187 #else
 188 #error  "Please fix <asm/byteorder.h>"
 189 #endif
 190         __be32  nonce;
 191 } __packed;
 192
 193 struct amt_header_mcast_data {
 194 #if defined(__LITTLE_ENDIAN_BITFIELD)
 195         u16     type:4,
 196                 version:4,
 197                 reserved:8;
 198 #elif defined(__BIG_ENDIAN_BITFIELD)
 199         u16     version:4,
 200                 type:4,
 201                 reserved:8;
 202 #else
 203 #error  "Please fix <asm/byteorder.h>"
 204 #endif
 205 } __packed;
 206
 207 struct amt_headers {
 208         union {
 209                 struct amt_header_discovery discovery;
 210                 struct amt_header_advertisement advertisement;
 211                 struct amt_header_request request;
 212                 struct amt_header_membership_query query;
 213                 struct amt_header_membership_update update;
 214                 struct amt_header_mcast_data data;
 215         };
 216 } __packed;
 217
 218 struct amt_gw_headers {
 219         union {
 220                 struct amt_header_discovery discovery;
 221                 struct amt_header_request request;
 222                 struct amt_header_membership_update update;
 223         };
 224 } __packed;
 225
 226 struct amt_relay_headers {
 227         union {
 228                 struct amt_header_advertisement advertisement;
 229                 struct amt_header_membership_query query;
 230                 struct amt_header_mcast_data data;
 231         };
 232 } __packed;
 233
 234 struct amt_skb_cb {
 235         struct amt_tunnel_list *tunnel;
 236 };
 237
 238 struct amt_tunnel_list {
 239         struct list_head        list;
 240         /* Protect All resources under an amt_tunne_list */
 241         spinlock_t              lock;
 242         struct amt_dev          *amt;
 243         u32                     nr_groups;
 244         u32                     nr_sources;
 245         enum amt_status         status;
 246         struct delayed_work     gc_wq;
 247         __be16                  source_port;
 248         __be32                  ip4;
 249         __be32                  nonce;
 250         siphash_key_t           key;
 251         u64                     mac:48,
 252                                 reserved:16;
 253         struct rcu_head         rcu;
 254         struct hlist_head       groups[];
 255 };
 256
 257 union amt_addr {
 258         __be32                  ip4;
 259 #if IS_ENABLED(CONFIG_IPV6)
 260         struct in6_addr         ip6;
 261 #endif
 262 };
 263
 264 /* RFC 3810
 265  *
 266  * When the router is in EXCLUDE mode, the router state is represented
 267  * by the notation EXCLUDE (X,Y), where X is called the "Requested List"
 268  * and Y is called the "Exclude List".  All sources, except those from
 269  * the Exclude List, will be forwarded by the router
 270  */
 271 enum amt_source_status {
 272         AMT_SOURCE_STATUS_NONE,
 273         /* Node of Requested List */
 274         AMT_SOURCE_STATUS_FWD,
 275         /* Node of Exclude List */
 276         AMT_SOURCE_STATUS_D_FWD,
 277 };
 278
 279 /* protected by gnode->lock */
 280 struct amt_source_node {
 281         struct hlist_node       node;
 282         struct amt_group_node   *gnode;
 283         struct delayed_work     source_timer;
 284         union amt_addr          source_addr;
 285         enum amt_source_status  status;
 286 #define AMT_SOURCE_OLD  0
 287 #define AMT_SOURCE_NEW  1
 288         u8                      flags;
 289         struct rcu_head         rcu;
 290 };
 291
 292 /* Protected by amt_tunnel_list->lock */
 293 struct amt_group_node {
 294         struct amt_dev          *amt;
 295         union amt_addr          group_addr;
 296         union amt_addr          host_addr;
 297         bool                    v6;
 298         u8                      filter_mode;
 299         u32                     nr_sources;
 300         struct amt_tunnel_list  *tunnel_list;
 301         struct hlist_node       node;
 302         struct delayed_work     group_timer;
 303         struct rcu_head         rcu;
 304         struct hlist_head       sources[];
 305 };
 306
 307 #define AMT_MAX_EVENTS  16
 308 struct amt_events {
 309         enum amt_event event;
 310         struct sk_buff *skb;
 311 };
 312
 313 struct amt_dev {
 314         struct net_device       *dev;
 315         struct net_device       *stream_dev;
 316         struct net              *net;
 317         /* Global lock for amt device */
 318         spinlock_t              lock;
 319         /* Used only in relay mode */
 320         struct list_head        tunnel_list;
 321         struct gro_cells        gro_cells;
 322
 323         /* Protected by RTNL */
 324         struct delayed_work     discovery_wq;
 325         /* Protected by RTNL */
 326         struct delayed_work     req_wq;
 327         /* Protected by RTNL */
 328         struct delayed_work     secret_wq;
 329         struct work_struct      event_wq;
 330         /* AMT status */
 331         enum amt_status         status;
 332         /* Generated key */
 333         siphash_key_t           key;
 334         struct socket     __rcu *sock;
 335         u32                     max_groups;
 336         u32                     max_sources;
 337         u32                     hash_buckets;
 338         u32                     hash_seed;
 339         /* Default 128 */
 340         u32                     max_tunnels;
 341         /* Default 128 */
 342         u32                     nr_tunnels;
 343         /* Gateway or Relay mode */
 344         u32                     mode;
 345         /* Default 2268 */
 346         __be16                  relay_port;
 347         /* Default 2268 */
 348         __be16                  gw_port;
 349         /* Outer local ip */
 350         __be32                  local_ip;
 351         /* Outer remote ip */
 352         __be32                  remote_ip;
 353         /* Outer discovery ip */
 354         __be32                  discovery_ip;
 355         /* Only used in gateway mode */
 356         __be32                  nonce;
 357         /* Gateway sent request and received query */
 358         bool                    ready4;
 359         bool                    ready6;
 360         u8                      req_cnt;
 361         u8                      qi;
 362         u64                     qrv;
 363         u64                     qri;
 364         /* Used only in gateway mode */
 365         u64                     mac:48,
 366                                 reserved:16;
 367         /* AMT gateway side message handler queue */
 368         struct amt_events       events[AMT_MAX_EVENTS];
 369         u8                      event_idx;
 370         u8                      nr_events;
 371 };
 372
 373 #define AMT_TOS                 0xc0
 374 #define AMT_IPHDR_OPTS          4
 375 #define AMT_IP6HDR_OPTS         8
 376 #define AMT_GC_INTERVAL         (30 * 1000)
 377 #define AMT_MAX_GROUP           32
 378 #define AMT_MAX_SOURCE          128
 379 #define AMT_HSIZE_SHIFT         8
 380 #define AMT_HSIZE               (1 << AMT_HSIZE_SHIFT)
 381
 382 #define AMT_DISCOVERY_TIMEOUT   5000
 383 #define AMT_INIT_REQ_TIMEOUT    1
 384 #define AMT_INIT_QUERY_INTERVAL 125
 385 #define AMT_MAX_REQ_TIMEOUT     120
 386 #define AMT_MAX_REQ_COUNT       3
 387 #define AMT_SECRET_TIMEOUT      60000
 388 #define IANA_AMT_UDP_PORT       2268
 389 #define AMT_MAX_TUNNELS         128
 390 #define AMT_MAX_REQS            128
 391 #define AMT_GW_HLEN (sizeof(struct iphdr) + \
 392                      sizeof(struct udphdr) + \
 393                      sizeof(struct amt_gw_headers))
 394 #define AMT_RELAY_HLEN (sizeof(struct iphdr) + \
 395                      sizeof(struct udphdr) + \
 396                      sizeof(struct amt_relay_headers))
 397
 398 static inline bool netif_is_amt(const struct net_device *dev)
 399 {
 400         return dev->rtnl_link_ops && !strcmp(dev->rtnl_link_ops->kind, "amt");
 401 }
 402
 403 static inline u64 amt_gmi(const struct amt_dev *amt)
 404 {
 405         return ((amt->qrv * amt->qi) + amt->qri) * 1000;
 406 }
 407
 408 #endif /* _NET_AMT_H_ */