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 CCIDS */
 173 enum {
 174         DCCPC_CCID2 = 2,
 175         DCCPC_CCID3 = 3,
 176 };
 177
 178 /* DCCP features */
 179 enum {
 180         DCCPF_RESERVED = 0,
 181         DCCPF_CCID = 1,
 182         DCCPF_SEQUENCE_WINDOW = 3,
 183         DCCPF_ACK_RATIO = 5,
 184         DCCPF_SEND_ACK_VECTOR = 6,
 185         DCCPF_SEND_NDP_COUNT = 7,
 186         /* 10-127 reserved */
 187         DCCPF_MIN_CCID_SPECIFIC = 128,
 188         DCCPF_MAX_CCID_SPECIFIC = 255,
 189 };
 190
 191 /* this structure is argument to DCCP_SOCKOPT_CHANGE_X */
 192 struct dccp_so_feat {
 193         __u8 dccpsf_feat;
 194         __u8 __user *dccpsf_val;
 195         __u8 dccpsf_len;
 196 };
 197
 198 /* DCCP socket options */
 199 #define DCCP_SOCKOPT_PACKET_SIZE        1
 200 #define DCCP_SOCKOPT_SERVICE            2
 201 #define DCCP_SOCKOPT_CHANGE_L           3
 202 #define DCCP_SOCKOPT_CHANGE_R           4
 203 #define DCCP_SOCKOPT_CCID_RX_INFO       128
 204 #define DCCP_SOCKOPT_CCID_TX_INFO       192
 205
 206 #define DCCP_SERVICE_LIST_MAX_LEN      32
 207
 208 #ifdef __KERNEL__
 209
 210 #include <linux/in.h>
 211 #include <linux/list.h>
 212 #include <linux/uio.h>
 213 #include <linux/workqueue.h>
 214
 215 #include <net/inet_connection_sock.h>
 216 #include <net/inet_sock.h>
 217 #include <net/inet_timewait_sock.h>
 218 #include <net/tcp_states.h>
 219
 220 enum dccp_state {
 221         DCCP_OPEN       = TCP_ESTABLISHED,
 222         DCCP_REQUESTING = TCP_SYN_SENT,
 223         DCCP_PARTOPEN   = TCP_FIN_WAIT1, /* FIXME:
 224                                             This mapping is horrible, but TCP has
 225                                             no matching state for DCCP_PARTOPEN,
 226                                             as TCP_SYN_RECV is already used by
 227                                             DCCP_RESPOND, why don't stop using TCP
 228                                             mapping of states? OK, now we don't use
 229                                             sk_stream_sendmsg anymore, so doesn't
 230                                             seem to exist any reason for us to
 231                                             do the TCP mapping here */
 232         DCCP_LISTEN     = TCP_LISTEN,
 233         DCCP_RESPOND    = TCP_SYN_RECV,
 234         DCCP_CLOSING    = TCP_CLOSING,
 235         DCCP_TIME_WAIT  = TCP_TIME_WAIT,
 236         DCCP_CLOSED     = TCP_CLOSE,
 237         DCCP_MAX_STATES = TCP_MAX_STATES,
 238 };
 239
 240 #define DCCP_STATE_MASK 0xf
 241 #define DCCP_ACTION_FIN (1<<7)
 242
 243 enum {
 244         DCCPF_OPEN       = TCPF_ESTABLISHED,
 245         DCCPF_REQUESTING = TCPF_SYN_SENT,
 246         DCCPF_PARTOPEN   = TCPF_FIN_WAIT1,
 247         DCCPF_LISTEN     = TCPF_LISTEN,
 248         DCCPF_RESPOND    = TCPF_SYN_RECV,
 249         DCCPF_CLOSING    = TCPF_CLOSING,
 250         DCCPF_TIME_WAIT  = TCPF_TIME_WAIT,
 251         DCCPF_CLOSED     = TCPF_CLOSE,
 252 };
 253
 254 static inline struct dccp_hdr *dccp_hdr(const struct sk_buff *skb)
 255 {
 256         return (struct dccp_hdr *)skb->h.raw;
 257 }
 258
 259 static inline struct dccp_hdr_ext *dccp_hdrx(const struct sk_buff *skb)
 260 {
 261         return (struct dccp_hdr_ext *)(skb->h.raw + sizeof(struct dccp_hdr));
 262 }
 263
 264 static inline unsigned int __dccp_basic_hdr_len(const struct dccp_hdr *dh)
 265 {
 266         return sizeof(*dh) + (dh->dccph_x ? sizeof(struct dccp_hdr_ext) : 0);
 267 }
 268
 269 static inline unsigned int dccp_basic_hdr_len(const struct sk_buff *skb)
 270 {
 271         const struct dccp_hdr *dh = dccp_hdr(skb);
 272         return __dccp_basic_hdr_len(dh);
 273 }
 274
 275 static inline __u64 dccp_hdr_seq(const struct sk_buff *skb)
 276 {
 277         const struct dccp_hdr *dh = dccp_hdr(skb);
 278         __u64 seq_nr =  ntohs(dh->dccph_seq);
 279
 280         if (dh->dccph_x != 0)
 281                 seq_nr = (seq_nr << 32) + ntohl(dccp_hdrx(skb)->dccph_seq_low);
 282         else
 283                 seq_nr += (u32)dh->dccph_seq2 << 16;
 284
 285         return seq_nr;
 286 }
 287
 288 static inline struct dccp_hdr_request *dccp_hdr_request(struct sk_buff *skb)
 289 {
 290         return (struct dccp_hdr_request *)(skb->h.raw + dccp_basic_hdr_len(skb));
 291 }
 292
 293 static inline struct dccp_hdr_ack_bits *dccp_hdr_ack_bits(const struct sk_buff *skb)
 294 {
 295         return (struct dccp_hdr_ack_bits *)(skb->h.raw + dccp_basic_hdr_len(skb));
 296 }
 297
 298 static inline u64 dccp_hdr_ack_seq(const struct sk_buff *skb)
 299 {
 300         const struct dccp_hdr_ack_bits *dhack = dccp_hdr_ack_bits(skb);
 301         return ((u64)ntohs(dhack->dccph_ack_nr_high) << 32) + ntohl(dhack->dccph_ack_nr_low);
 302 }
 303
 304 static inline struct dccp_hdr_response *dccp_hdr_response(struct sk_buff *skb)
 305 {
 306         return (struct dccp_hdr_response *)(skb->h.raw + dccp_basic_hdr_len(skb));
 307 }
 308
 309 static inline struct dccp_hdr_reset *dccp_hdr_reset(struct sk_buff *skb)
 310 {
 311         return (struct dccp_hdr_reset *)(skb->h.raw + dccp_basic_hdr_len(skb));
 312 }
 313
 314 static inline unsigned int __dccp_hdr_len(const struct dccp_hdr *dh)
 315 {
 316         return __dccp_basic_hdr_len(dh) +
 317                dccp_packet_hdr_len(dh->dccph_type);
 318 }
 319
 320 static inline unsigned int dccp_hdr_len(const struct sk_buff *skb)
 321 {
 322         return __dccp_hdr_len(dccp_hdr(skb));
 323 }
 324
 325
 326 /* initial values for each feature */
 327 #define DCCPF_INITIAL_SEQUENCE_WINDOW           100
 328 #define DCCPF_INITIAL_ACK_RATIO                 2
 329 #define DCCPF_INITIAL_CCID                      DCCPC_CCID2
 330 #define DCCPF_INITIAL_SEND_ACK_VECTOR           1
 331 /* FIXME: for now we're default to 1 but it should really be 0 */
 332 #define DCCPF_INITIAL_SEND_NDP_COUNT            1
 333
 334 #define DCCP_NDP_LIMIT 0xFFFFFF
 335
 336 /**
 337   * struct dccp_minisock - Minimal DCCP connection representation
 338   *
 339   * Will be used to pass the state from dccp_request_sock to dccp_sock.
 340   *
 341   * @dccpms_sequence_window - Sequence Window Feature (section 7.5.2)
 342   * @dccpms_ccid - Congestion Control Id (CCID) (section 10)
 343   * @dccpms_send_ack_vector - Send Ack Vector Feature (section 11.5)
 344   * @dccpms_send_ndp_count - Send NDP Count Feature (7.7.2)
 345   */
 346 struct dccp_minisock {
 347         __u64                   dccpms_sequence_window;
 348         __u8                    dccpms_rx_ccid;
 349         __u8                    dccpms_tx_ccid;
 350         __u8                    dccpms_send_ack_vector;
 351         __u8                    dccpms_send_ndp_count;
 352         __u8                    dccpms_ack_ratio;
 353         struct list_head        dccpms_pending;
 354         struct list_head        dccpms_conf;
 355 };
 356
 357 struct dccp_opt_conf {
 358         __u8                    *dccpoc_val;
 359         __u8                    dccpoc_len;
 360 };
 361
 362 struct dccp_opt_pend {
 363         struct list_head        dccpop_node;
 364         __u8                    dccpop_type;
 365         __u8                    dccpop_feat;
 366         __u8                    *dccpop_val;
 367         __u8                    dccpop_len;
 368         int                     dccpop_conf;
 369         struct dccp_opt_conf    *dccpop_sc;
 370 };
 371
 372 extern void __dccp_minisock_init(struct dccp_minisock *dmsk);
 373 extern void dccp_minisock_init(struct dccp_minisock *dmsk);
 374
 375 extern int dccp_parse_options(struct sock *sk, struct sk_buff *skb);
 376
 377 struct dccp_request_sock {
 378         struct inet_request_sock dreq_inet_rsk;
 379         __u64                    dreq_iss;
 380         __u64                    dreq_isr;
 381         __be32                   dreq_service;
 382 };
 383
 384 static inline struct dccp_request_sock *dccp_rsk(const struct request_sock *req)
 385 {
 386         return (struct dccp_request_sock *)req;
 387 }
 388
 389 extern struct inet_timewait_death_row dccp_death_row;
 390
 391 struct dccp_options_received {
 392         u32     dccpor_ndp; /* only 24 bits */
 393         u32     dccpor_timestamp;
 394         u32     dccpor_timestamp_echo;
 395         u32     dccpor_elapsed_time;
 396 };
 397
 398 struct ccid;
 399
 400 enum dccp_role {
 401         DCCP_ROLE_UNDEFINED,
 402         DCCP_ROLE_LISTEN,
 403         DCCP_ROLE_CLIENT,
 404         DCCP_ROLE_SERVER,
 405 };
 406
 407 struct dccp_service_list {
 408         __u32   dccpsl_nr;
 409         __be32  dccpsl_list[0];
 410 };
 411
 412 #define DCCP_SERVICE_INVALID_VALUE htonl((__u32)-1)
 413 #define DCCP_SERVICE_CODE_IS_ABSENT              0
 414
 415 static inline int dccp_list_has_service(const struct dccp_service_list *sl,
 416                                         const __be32 service)
 417 {
 418         if (likely(sl != NULL)) {
 419                 u32 i = sl->dccpsl_nr;
 420                 while (i--)
 421                         if (sl->dccpsl_list[i] == service)
 422                                 return 1;
 423         }
 424         return 0;
 425 }
 426
 427 struct dccp_ackvec;
 428
 429 /**
 430  * struct dccp_sock - DCCP socket state
 431  *
 432  * @dccps_swl - sequence number window low
 433  * @dccps_swh - sequence number window high
 434  * @dccps_awl - acknowledgement number window low
 435  * @dccps_awh - acknowledgement number window high
 436  * @dccps_iss - initial sequence number sent
 437  * @dccps_isr - initial sequence number received
 438  * @dccps_osr - first OPEN sequence number received
 439  * @dccps_gss - greatest sequence number sent
 440  * @dccps_gsr - greatest valid sequence number received
 441  * @dccps_gar - greatest valid ack number received on a non-Sync; initialized to %dccps_iss
 442  * @dccps_timestamp_time - time of latest TIMESTAMP option
 443  * @dccps_timestamp_echo - latest timestamp received on a TIMESTAMP option
 444  * @dccps_packet_size - Set thru setsockopt
 445  * @dccps_role - Role of this sock, one of %dccp_role
 446  * @dccps_ndp_count - number of Non Data Packets since last data packet
 447  * @dccps_hc_rx_ackvec - rx half connection ack vector
 448  * @dccps_xmit_timer - timer for when CCID is not ready to send
 449  */
 450 struct dccp_sock {
 451         /* inet_connection_sock has to be the first member of dccp_sock */
 452         struct inet_connection_sock     dccps_inet_connection;
 453         __u64                           dccps_swl;
 454         __u64                           dccps_swh;
 455         __u64                           dccps_awl;
 456         __u64                           dccps_awh;
 457         __u64                           dccps_iss;
 458         __u64                           dccps_isr;
 459         __u64                           dccps_osr;
 460         __u64                           dccps_gss;
 461         __u64                           dccps_gsr;
 462         __u64                           dccps_gar;
 463         __be32                          dccps_service;
 464         struct dccp_service_list        *dccps_service_list;
 465         struct timeval                  dccps_timestamp_time;
 466         __u32                           dccps_timestamp_echo;
 467         __u32                           dccps_packet_size;
 468         __u16                           dccps_l_ack_ratio;
 469         __u16                           dccps_r_ack_ratio;
 470         unsigned long                   dccps_ndp_count;
 471         __u32                           dccps_mss_cache;
 472         struct dccp_minisock            dccps_minisock;
 473         struct dccp_ackvec              *dccps_hc_rx_ackvec;
 474         struct ccid                     *dccps_hc_rx_ccid;
 475         struct ccid                     *dccps_hc_tx_ccid;
 476         struct dccp_options_received    dccps_options_received;
 477         struct timeval                  dccps_epoch;
 478         enum dccp_role                  dccps_role:2;
 479         __u8                            dccps_hc_rx_insert_options:1;
 480         __u8                            dccps_hc_tx_insert_options:1;
 481         struct timer_list               dccps_xmit_timer;
 482 };
 483
 484 static inline struct dccp_sock *dccp_sk(const struct sock *sk)
 485 {
 486         return (struct dccp_sock *)sk;
 487 }
 488
 489 static inline struct dccp_minisock *dccp_msk(const struct sock *sk)
 490 {
 491         return (struct dccp_minisock *)&dccp_sk(sk)->dccps_minisock;
 492 }
 493
 494 static inline const char *dccp_role(const struct sock *sk)
 495 {
 496         switch (dccp_sk(sk)->dccps_role) {
 497         case DCCP_ROLE_UNDEFINED: return "undefined";
 498         case DCCP_ROLE_LISTEN:    return "listen";
 499         case DCCP_ROLE_SERVER:    return "server";
 500         case DCCP_ROLE_CLIENT:    return "client";
 501         }
 502         return NULL;
 503 }
 504
 505 #endif /* __KERNEL__ */
 506
 507 #endif /* _LINUX_DCCP_H */