include/linux/dccp.h

   1 #ifndef _LINUX_DCCP_H
   2 #define _LINUX_DCCP_H
   3
   4 #include <linux/types.h>
   5 #include <asm/byteorder.h>
   6
   7 /**
   8  * struct dccp_hdr - generic part of DCCP packet header
   9  *
  10  * @dccph_sport - Relevant port on the endpoint that sent this packet
  11  * @dccph_dport - Relevant port on the other endpoint
  12  * @dccph_doff - Data Offset from the start of the DCCP header, in 32-bit words
  13  * @dccph_ccval - Used by the HC-Sender CCID
  14  * @dccph_cscov - Parts of the packet that are covered by the Checksum field
  15  * @dccph_checksum - Internet checksum, depends on dccph_cscov
  16  * @dccph_x - 0 = 24 bit sequence number, 1 = 48
  17  * @dccph_type - packet type, see DCCP_PKT_ prefixed macros
  18  * @dccph_seq - sequence number high or low order 24 bits, depends on dccph_x
  19  */
  20 struct dccp_hdr {
  21         __be16  dccph_sport,
  22                 dccph_dport;
  23         __u8    dccph_doff;
  24 #if defined(__LITTLE_ENDIAN_BITFIELD)
  25         __u8    dccph_cscov:4,
  26                 dccph_ccval:4;
  27 #elif defined(__BIG_ENDIAN_BITFIELD)
  28         __u8    dccph_ccval:4,
  29                 dccph_cscov:4;
  30 #else
  31 #error  "Adjust your <asm/byteorder.h> defines"
  32 #endif
  33         __u16   dccph_checksum;
  34 #if defined(__LITTLE_ENDIAN_BITFIELD)
  35         __u8    dccph_x:1,
  36                 dccph_type:4,
  37                 dccph_reserved:3;
  38 #elif defined(__BIG_ENDIAN_BITFIELD)
  39         __u8    dccph_reserved:3,
  40                 dccph_type:4,
  41                 dccph_x:1;
  42 #else
  43 #error  "Adjust your <asm/byteorder.h> defines"
  44 #endif
  45         __u8    dccph_seq2;
  46         __be16  dccph_seq;
  47 };
  48
  49 /**
  50  * struct dccp_hdr_ext - the low bits of a 48 bit seq packet
  51  *
  52  * @dccph_seq_low - low 24 bits of a 48 bit seq packet
  53  */
  54 struct dccp_hdr_ext {
  55         __be32  dccph_seq_low;
  56 };
  57
  58 /**
  59  * struct dccp_hdr_request - Conection initiation request header
  60  *
  61  * @dccph_req_service - Service to which the client app wants to connect
  62  * @dccph_req_options - list of options (must be a multiple of 32 bits
  63  */
  64 struct dccp_hdr_request {
  65         __be32  dccph_req_service;
  66 };
  67 /**
  68  * struct dccp_hdr_ack_bits - acknowledgment bits common to most packets
  69  *
  70  * @dccph_resp_ack_nr_high - 48 bit ack number high order bits, contains GSR
  71  * @dccph_resp_ack_nr_low - 48 bit ack number low order bits, contains GSR
  72  */
  73 struct dccp_hdr_ack_bits {
  74         __be16  dccph_reserved1;
  75         __be16  dccph_ack_nr_high;
  76         __be32  dccph_ack_nr_low;
  77 };
  78 /**
  79  * struct dccp_hdr_response - Conection initiation response header
  80  *
  81  * @dccph_resp_ack_nr_high - 48 bit ack number high order bits, contains GSR
  82  * @dccph_resp_ack_nr_low - 48 bit ack number low order bits, contains GSR
  83  * @dccph_resp_service - Echoes the Service Code on a received DCCP-Request
  84  * @dccph_resp_options - list of options (must be a multiple of 32 bits
  85  */
  86 struct dccp_hdr_response {
  87         struct dccp_hdr_ack_bits        dccph_resp_ack;
  88         __be32                          dccph_resp_service;
  89 };
  90
  91 /**
  92  * struct dccp_hdr_reset - Unconditionally shut down a connection
  93  *
  94  * @dccph_reset_service - Echoes the Service Code on a received DCCP-Request
  95  * @dccph_reset_options - list of options (must be a multiple of 32 bits
  96  */
  97 struct dccp_hdr_reset {
  98         struct dccp_hdr_ack_bits        dccph_reset_ack;
  99         __u8                            dccph_reset_code,
 100                                         dccph_reset_data[3];
 101 };
 102
 103 enum dccp_pkt_type {
 104         DCCP_PKT_REQUEST = 0,
 105         DCCP_PKT_RESPONSE,
 106         DCCP_PKT_DATA,
 107         DCCP_PKT_ACK,
 108         DCCP_PKT_DATAACK,
 109         DCCP_PKT_CLOSEREQ,
 110         DCCP_PKT_CLOSE,
 111         DCCP_PKT_RESET,
 112         DCCP_PKT_SYNC,
 113         DCCP_PKT_SYNCACK,
 114         DCCP_PKT_INVALID,
 115 };
 116
 117 #define DCCP_NR_PKT_TYPES DCCP_PKT_INVALID
 118
 119 static inline unsigned int dccp_packet_hdr_len(const __u8 type)
 120 {
 121         if (type == DCCP_PKT_DATA)
 122                 return 0;
 123         if (type == DCCP_PKT_DATAACK    ||
 124             type == DCCP_PKT_ACK        ||
 125             type == DCCP_PKT_SYNC       ||
 126             type == DCCP_PKT_SYNCACK    ||
 127             type == DCCP_PKT_CLOSE      ||
 128             type == DCCP_PKT_CLOSEREQ)
 129                 return sizeof(struct dccp_hdr_ack_bits);
 130         if (type == DCCP_PKT_REQUEST)
 131                 return sizeof(struct dccp_hdr_request);
 132         if (type == DCCP_PKT_RESPONSE)
 133                 return sizeof(struct dccp_hdr_response);
 134         return sizeof(struct dccp_hdr_reset);
 135 }
 136 enum dccp_reset_codes {
 137         DCCP_RESET_CODE_UNSPECIFIED = 0,
 138         DCCP_RESET_CODE_CLOSED,
 139         DCCP_RESET_CODE_ABORTED,
 140         DCCP_RESET_CODE_NO_CONNECTION,
 141         DCCP_RESET_CODE_PACKET_ERROR,
 142         DCCP_RESET_CODE_OPTION_ERROR,
 143         DCCP_RESET_CODE_MANDATORY_ERROR,
 144         DCCP_RESET_CODE_CONNECTION_REFUSED,
 145         DCCP_RESET_CODE_BAD_SERVICE_CODE,
 146         DCCP_RESET_CODE_TOO_BUSY,
 147         DCCP_RESET_CODE_BAD_INIT_COOKIE,
 148         DCCP_RESET_CODE_AGGRESSION_PENALTY,
 149 };
 150
 151 /* DCCP options */
 152 enum {
 153         DCCPO_PADDING = 0,
 154         DCCPO_MANDATORY = 1,
 155         DCCPO_MIN_RESERVED = 3,
 156         DCCPO_MAX_RESERVED = 31,
 157         DCCPO_CHANGE_L = 32,
 158         DCCPO_CONFIRM_L = 33,
 159         DCCPO_CHANGE_R = 34,
 160         DCCPO_CONFIRM_R = 35,
 161         DCCPO_NDP_COUNT = 37,
 162         DCCPO_ACK_VECTOR_0 = 38,
 163         DCCPO_ACK_VECTOR_1 = 39,
 164         DCCPO_TIMESTAMP = 41,
 165         DCCPO_TIMESTAMP_ECHO = 42,
 166         DCCPO_ELAPSED_TIME = 43,
 167         DCCPO_MAX = 45,
 168         DCCPO_MIN_CCID_SPECIFIC = 128,
 169         DCCPO_MAX_CCID_SPECIFIC = 255,
 170 };
 171
 172 /* DCCP features */
 173 enum {
 174         DCCPF_RESERVED = 0,
 175         DCCPF_CCID = 1,
 176         DCCPF_SEQUENCE_WINDOW = 3,
 177         DCCPF_ACK_RATIO = 5,
 178         DCCPF_SEND_ACK_VECTOR = 6,
 179         DCCPF_SEND_NDP_COUNT = 7,
 180         /* 10-127 reserved */
 181         DCCPF_MIN_CCID_SPECIFIC = 128,
 182         DCCPF_MAX_CCID_SPECIFIC = 255,
 183 };
 184
 185 /* this structure is argument to DCCP_SOCKOPT_CHANGE_X */
 186 struct dccp_so_feat {
 187         __u8 dccpsf_feat;
 188         __u8 *dccpsf_val;
 189         __u8 dccpsf_len;
 190 };
 191
 192 /* DCCP socket options */
 193 #define DCCP_SOCKOPT_PACKET_SIZE        1
 194 #define DCCP_SOCKOPT_SERVICE            2
 195 #define DCCP_SOCKOPT_CHANGE_L           3
 196 #define DCCP_SOCKOPT_CHANGE_R           4
 197 #define DCCP_SOCKOPT_CCID_RX_INFO       128
 198 #define DCCP_SOCKOPT_CCID_TX_INFO       192
 199
 200 #define DCCP_SERVICE_LIST_MAX_LEN      32
 201
 202 #ifdef __KERNEL__
 203
 204 #include <linux/in.h>
 205 #include <linux/list.h>
 206 #include <linux/uio.h>
 207 #include <linux/workqueue.h>
 208
 209 #include <net/inet_connection_sock.h>
 210 #include <net/inet_sock.h>
 211 #include <net/inet_timewait_sock.h>
 212 #include <net/tcp_states.h>
 213
 214 enum dccp_state {
 215         DCCP_OPEN       = TCP_ESTABLISHED,
 216         DCCP_REQUESTING = TCP_SYN_SENT,
 217         DCCP_PARTOPEN   = TCP_FIN_WAIT1, /* FIXME:
 218                                             This mapping is horrible, but TCP has
 219                                             no matching state for DCCP_PARTOPEN,
 220                                             as TCP_SYN_RECV is already used by
 221                                             DCCP_RESPOND, why don't stop using TCP
 222                                             mapping of states? OK, now we don't use
 223                                             sk_stream_sendmsg anymore, so doesn't
 224                                             seem to exist any reason for us to
 225                                             do the TCP mapping here */
 226         DCCP_LISTEN     = TCP_LISTEN,
 227         DCCP_RESPOND    = TCP_SYN_RECV,
 228         DCCP_CLOSING    = TCP_CLOSING,
 229         DCCP_TIME_WAIT  = TCP_TIME_WAIT,
 230         DCCP_CLOSED     = TCP_CLOSE,
 231         DCCP_MAX_STATES = TCP_MAX_STATES,
 232 };
 233
 234 #define DCCP_STATE_MASK 0xf
 235 #define DCCP_ACTION_FIN (1<<7)
 236
 237 enum {
 238         DCCPF_OPEN       = TCPF_ESTABLISHED,
 239         DCCPF_REQUESTING = TCPF_SYN_SENT,
 240         DCCPF_PARTOPEN   = TCPF_FIN_WAIT1,
 241         DCCPF_LISTEN     = TCPF_LISTEN,
 242         DCCPF_RESPOND    = TCPF_SYN_RECV,
 243         DCCPF_CLOSING    = TCPF_CLOSING,
 244         DCCPF_TIME_WAIT  = TCPF_TIME_WAIT,
 245         DCCPF_CLOSED     = TCPF_CLOSE,
 246 };
 247
 248 static inline struct dccp_hdr *dccp_hdr(const struct sk_buff *skb)
 249 {
 250         return (struct dccp_hdr *)skb->h.raw;
 251 }
 252
 253 static inline struct dccp_hdr_ext *dccp_hdrx(const struct sk_buff *skb)
 254 {
 255         return (struct dccp_hdr_ext *)(skb->h.raw + sizeof(struct dccp_hdr));
 256 }
 257
 258 static inline unsigned int __dccp_basic_hdr_len(const struct dccp_hdr *dh)
 259 {
 260         return sizeof(*dh) + (dh->dccph_x ? sizeof(struct dccp_hdr_ext) : 0);
 261 }
 262
 263 static inline unsigned int dccp_basic_hdr_len(const struct sk_buff *skb)
 264 {
 265         const struct dccp_hdr *dh = dccp_hdr(skb);
 266         return __dccp_basic_hdr_len(dh);
 267 }
 268
 269 static inline __u64 dccp_hdr_seq(const struct sk_buff *skb)
 270 {
 271         const struct dccp_hdr *dh = dccp_hdr(skb);
 272         __u64 seq_nr =  ntohs(dh->dccph_seq);
 273
 274         if (dh->dccph_x != 0)
 275                 seq_nr = (seq_nr << 32) + ntohl(dccp_hdrx(skb)->dccph_seq_low);
 276         else
 277                 seq_nr += (u32)dh->dccph_seq2 << 16;
 278
 279         return seq_nr;
 280 }
 281
 282 static inline struct dccp_hdr_request *dccp_hdr_request(struct sk_buff *skb)
 283 {
 284         return (struct dccp_hdr_request *)(skb->h.raw + dccp_basic_hdr_len(skb));
 285 }
 286
 287 static inline struct dccp_hdr_ack_bits *dccp_hdr_ack_bits(const struct sk_buff *skb)
 288 {
 289         return (struct dccp_hdr_ack_bits *)(skb->h.raw + dccp_basic_hdr_len(skb));
 290 }
 291
 292 static inline u64 dccp_hdr_ack_seq(const struct sk_buff *skb)
 293 {
 294         const struct dccp_hdr_ack_bits *dhack = dccp_hdr_ack_bits(skb);
 295         return ((u64)ntohs(dhack->dccph_ack_nr_high) << 32) + ntohl(dhack->dccph_ack_nr_low);
 296 }
 297
 298 static inline struct dccp_hdr_response *dccp_hdr_response(struct sk_buff *skb)
 299 {
 300         return (struct dccp_hdr_response *)(skb->h.raw + dccp_basic_hdr_len(skb));
 301 }
 302
 303 static inline struct dccp_hdr_reset *dccp_hdr_reset(struct sk_buff *skb)
 304 {
 305         return (struct dccp_hdr_reset *)(skb->h.raw + dccp_basic_hdr_len(skb));
 306 }
 307
 308 static inline unsigned int __dccp_hdr_len(const struct dccp_hdr *dh)
 309 {
 310         return __dccp_basic_hdr_len(dh) +
 311                dccp_packet_hdr_len(dh->dccph_type);
 312 }
 313
 314 static inline unsigned int dccp_hdr_len(const struct sk_buff *skb)
 315 {
 316         return __dccp_hdr_len(dccp_hdr(skb));
 317 }
 318
 319
 320 /* initial values for each feature */
 321 #define DCCPF_INITIAL_SEQUENCE_WINDOW           100
 322 #define DCCPF_INITIAL_ACK_RATIO                 2
 323 #define DCCPF_INITIAL_CCID                      2
 324 #define DCCPF_INITIAL_SEND_ACK_VECTOR           1
 325 /* FIXME: for now we're default to 1 but it should really be 0 */
 326 #define DCCPF_INITIAL_SEND_NDP_COUNT            1
 327
 328 #define DCCP_NDP_LIMIT 0xFFFFFF
 329
 330 /**
 331   * struct dccp_options - option values for a DCCP connection
 332   *     @dccpo_sequence_window - Sequence Window Feature (section 7.5.2)
 333   *     @dccpo_ccid - Congestion Control Id (CCID) (section 10)
 334   *     @dccpo_send_ack_vector - Send Ack Vector Feature (section 11.5)
 335   *     @dccpo_send_ndp_count - Send NDP Count Feature (7.7.2)
 336   */
 337 struct dccp_options {
 338         __u64   dccpo_sequence_window;
 339         __u8    dccpo_rx_ccid;
 340         __u8    dccpo_tx_ccid;
 341         __u8    dccpo_send_ack_vector;
 342         __u8    dccpo_send_ndp_count;
 343         __u8                    dccpo_ack_ratio;
 344         struct list_head        dccpo_pending;
 345         struct list_head        dccpo_conf;
 346 };
 347
 348 struct dccp_opt_conf {
 349         __u8                    *dccpoc_val;
 350         __u8                    dccpoc_len;
 351 };
 352
 353 struct dccp_opt_pend {
 354         struct list_head        dccpop_node;
 355         __u8                    dccpop_type;
 356         __u8                    dccpop_feat;
 357         __u8                    *dccpop_val;
 358         __u8                    dccpop_len;
 359         int                     dccpop_conf;
 360         struct dccp_opt_conf    *dccpop_sc;
 361 };
 362
 363 extern void __dccp_options_init(struct dccp_options *dccpo);
 364 extern void dccp_options_init(struct dccp_options *dccpo);
 365 extern int dccp_parse_options(struct sock *sk, struct sk_buff *skb);
 366
 367 struct dccp_request_sock {
 368         struct inet_request_sock dreq_inet_rsk;
 369         __u64                    dreq_iss;
 370         __u64                    dreq_isr;
 371         __be32                   dreq_service;
 372 };
 373
 374 static inline struct dccp_request_sock *dccp_rsk(const struct request_sock *req)
 375 {
 376         return (struct dccp_request_sock *)req;
 377 }
 378
 379 extern struct inet_timewait_death_row dccp_death_row;
 380
 381 struct dccp_options_received {
 382         u32     dccpor_ndp; /* only 24 bits */
 383         u32     dccpor_timestamp;
 384         u32     dccpor_timestamp_echo;
 385         u32     dccpor_elapsed_time;
 386 };
 387
 388 struct ccid;
 389
 390 enum dccp_role {
 391         DCCP_ROLE_UNDEFINED,
 392         DCCP_ROLE_LISTEN,
 393         DCCP_ROLE_CLIENT,
 394         DCCP_ROLE_SERVER,
 395 };
 396
 397 struct dccp_service_list {
 398         __u32   dccpsl_nr;
 399         __be32  dccpsl_list[0];
 400 };
 401
 402 #define DCCP_SERVICE_INVALID_VALUE htonl((__u32)-1)
 403
 404 static inline int dccp_list_has_service(const struct dccp_service_list *sl,
 405                                         const __be32 service)
 406 {
 407         if (likely(sl != NULL)) {
 408                 u32 i = sl->dccpsl_nr;
 409                 while (i--)
 410                         if (sl->dccpsl_list[i] == service)
 411                                 return 1;
 412         }
 413         return 0;
 414 }
 415
 416 struct dccp_ackvec;
 417
 418 /**
 419  * struct dccp_sock - DCCP socket state
 420  *
 421  * @dccps_swl - sequence number window low
 422  * @dccps_swh - sequence number window high
 423  * @dccps_awl - acknowledgement number window low
 424  * @dccps_awh - acknowledgement number window high
 425  * @dccps_iss - initial sequence number sent
 426  * @dccps_isr - initial sequence number received
 427  * @dccps_osr - first OPEN sequence number received
 428  * @dccps_gss - greatest sequence number sent
 429  * @dccps_gsr - greatest valid sequence number received
 430  * @dccps_gar - greatest valid ack number received on a non-Sync; initialized to %dccps_iss
 431  * @dccps_timestamp_time - time of latest TIMESTAMP option
 432  * @dccps_timestamp_echo - latest timestamp received on a TIMESTAMP option
 433  * @dccps_packet_size - Set thru setsockopt
 434  * @dccps_role - Role of this sock, one of %dccp_role
 435  * @dccps_ndp_count - number of Non Data Packets since last data packet
 436  * @dccps_hc_rx_ackvec - rx half connection ack vector
 437  */
 438 struct dccp_sock {
 439         /* inet_connection_sock has to be the first member of dccp_sock */
 440         struct inet_connection_sock     dccps_inet_connection;
 441         __u64                           dccps_swl;
 442         __u64                           dccps_swh;
 443         __u64                           dccps_awl;
 444         __u64                           dccps_awh;
 445         __u64                           dccps_iss;
 446         __u64                           dccps_isr;
 447         __u64                           dccps_osr;
 448         __u64                           dccps_gss;
 449         __u64                           dccps_gsr;
 450         __u64                           dccps_gar;
 451         __be32                          dccps_service;
 452         struct dccp_service_list        *dccps_service_list;
 453         struct timeval                  dccps_timestamp_time;
 454         __u32                           dccps_timestamp_echo;
 455         __u32                           dccps_packet_size;
 456         __u16                           dccps_l_ack_ratio;
 457         __u16                           dccps_r_ack_ratio;
 458         unsigned long                   dccps_ndp_count;
 459         __u32                           dccps_mss_cache;
 460         struct dccp_options             dccps_options;
 461         struct dccp_ackvec              *dccps_hc_rx_ackvec;
 462         struct ccid                     *dccps_hc_rx_ccid;
 463         struct ccid                     *dccps_hc_tx_ccid;
 464         struct dccp_options_received    dccps_options_received;
 465         struct timeval                  dccps_epoch;
 466         enum dccp_role                  dccps_role:2;
 467         __u8                            dccps_hc_rx_insert_options:1;
 468         __u8                            dccps_hc_tx_insert_options:1;
 469 };
 470
 471 static inline struct dccp_sock *dccp_sk(const struct sock *sk)
 472 {
 473         return (struct dccp_sock *)sk;
 474 }
 475
 476 static inline int dccp_service_not_initialized(const struct sock *sk)
 477 {
 478         return dccp_sk(sk)->dccps_service == DCCP_SERVICE_INVALID_VALUE;
 479 }
 480
 481 static inline const char *dccp_role(const struct sock *sk)
 482 {
 483         switch (dccp_sk(sk)->dccps_role) {
 484         case DCCP_ROLE_UNDEFINED: return "undefined";
 485         case DCCP_ROLE_LISTEN:    return "listen";
 486         case DCCP_ROLE_SERVER:    return "server";
 487         case DCCP_ROLE_CLIENT:    return "client";
 488         }
 489         return NULL;
 490 }
 491
 492 #endif /* __KERNEL__ */
 493
 494 #endif /* _LINUX_DCCP_H */