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         __sum16 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 - Connection initiation request header
  60  *
  61  * @dccph_req_service - Service to which the client app wants to connect
  62  */
  63 struct dccp_hdr_request {
  64         __be32  dccph_req_service;
  65 };
  66 /**
  67  * struct dccp_hdr_ack_bits - acknowledgment bits common to most packets
  68  *
  69  * @dccph_resp_ack_nr_high - 48 bit ack number high order bits, contains GSR
  70  * @dccph_resp_ack_nr_low - 48 bit ack number low order bits, contains GSR
  71  */
  72 struct dccp_hdr_ack_bits {
  73         __be16  dccph_reserved1;
  74         __be16  dccph_ack_nr_high;
  75         __be32  dccph_ack_nr_low;
  76 };
  77 /**
  78  * struct dccp_hdr_response - Connection initiation response header
  79  *
  80  * @dccph_resp_ack - 48 bit Acknowledgment Number Subheader (5.3)
  81  * @dccph_resp_service - Echoes the Service Code on a received DCCP-Request
  82  */
  83 struct dccp_hdr_response {
  84         struct dccp_hdr_ack_bits        dccph_resp_ack;
  85         __be32                          dccph_resp_service;
  86 };
  87
  88 /**
  89  * struct dccp_hdr_reset - Unconditionally shut down a connection
  90  *
  91  * @dccph_reset_ack - 48 bit Acknowledgment Number Subheader (5.6)
  92  * @dccph_reset_code - one of %dccp_reset_codes
  93  * @dccph_reset_data - the Data 1 ... Data 3 fields from 5.6
  94  */
  95 struct dccp_hdr_reset {
  96         struct dccp_hdr_ack_bits        dccph_reset_ack;
  97         __u8                            dccph_reset_code,
  98                                         dccph_reset_data[3];
  99 };
 100
 101 enum dccp_pkt_type {
 102         DCCP_PKT_REQUEST = 0,
 103         DCCP_PKT_RESPONSE,
 104         DCCP_PKT_DATA,
 105         DCCP_PKT_ACK,
 106         DCCP_PKT_DATAACK,
 107         DCCP_PKT_CLOSEREQ,
 108         DCCP_PKT_CLOSE,
 109         DCCP_PKT_RESET,
 110         DCCP_PKT_SYNC,
 111         DCCP_PKT_SYNCACK,
 112         DCCP_PKT_INVALID,
 113 };
 114
 115 #define DCCP_NR_PKT_TYPES DCCP_PKT_INVALID
 116
 117 static inline unsigned int dccp_packet_hdr_len(const __u8 type)
 118 {
 119         if (type == DCCP_PKT_DATA)
 120                 return 0;
 121         if (type == DCCP_PKT_DATAACK    ||
 122             type == DCCP_PKT_ACK        ||
 123             type == DCCP_PKT_SYNC       ||
 124             type == DCCP_PKT_SYNCACK    ||
 125             type == DCCP_PKT_CLOSE      ||
 126             type == DCCP_PKT_CLOSEREQ)
 127                 return sizeof(struct dccp_hdr_ack_bits);
 128         if (type == DCCP_PKT_REQUEST)
 129                 return sizeof(struct dccp_hdr_request);
 130         if (type == DCCP_PKT_RESPONSE)
 131                 return sizeof(struct dccp_hdr_response);
 132         return sizeof(struct dccp_hdr_reset);
 133 }
 134 enum dccp_reset_codes {
 135         DCCP_RESET_CODE_UNSPECIFIED = 0,
 136         DCCP_RESET_CODE_CLOSED,
 137         DCCP_RESET_CODE_ABORTED,
 138         DCCP_RESET_CODE_NO_CONNECTION,
 139         DCCP_RESET_CODE_PACKET_ERROR,
 140         DCCP_RESET_CODE_OPTION_ERROR,
 141         DCCP_RESET_CODE_MANDATORY_ERROR,
 142         DCCP_RESET_CODE_CONNECTION_REFUSED,
 143         DCCP_RESET_CODE_BAD_SERVICE_CODE,
 144         DCCP_RESET_CODE_TOO_BUSY,
 145         DCCP_RESET_CODE_BAD_INIT_COOKIE,
 146         DCCP_RESET_CODE_AGGRESSION_PENALTY,
 147
 148         DCCP_MAX_RESET_CODES            /* Leave at the end!  */
 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 (RFC 4340 section 6.4) */
 179 enum {
 180         DCCPF_RESERVED = 0,
 181         DCCPF_CCID = 1,
 182         DCCPF_SHORT_SEQNOS = 2,         /* XXX: not yet implemented */
 183         DCCPF_SEQUENCE_WINDOW = 3,
 184         DCCPF_ECN_INCAPABLE = 4,        /* XXX: not yet implemented */
 185         DCCPF_ACK_RATIO = 5,
 186         DCCPF_SEND_ACK_VECTOR = 6,
 187         DCCPF_SEND_NDP_COUNT = 7,
 188         DCCPF_MIN_CSUM_COVER = 8,
 189         DCCPF_DATA_CHECKSUM = 9,        /* XXX: not yet implemented */
 190         /* 10-127 reserved */
 191         DCCPF_MIN_CCID_SPECIFIC = 128,
 192         DCCPF_MAX_CCID_SPECIFIC = 255,
 193 };
 194
 195 /* this structure is argument to DCCP_SOCKOPT_CHANGE_X */
 196 struct dccp_so_feat {
 197         __u8 dccpsf_feat;
 198         __u8 __user *dccpsf_val;
 199         __u8 dccpsf_len;
 200 };
 201
 202 /* DCCP socket options */
 203 #define DCCP_SOCKOPT_PACKET_SIZE        1 /* XXX deprecated, without effect */
 204 #define DCCP_SOCKOPT_SERVICE            2
 205 #define DCCP_SOCKOPT_CHANGE_L           3
 206 #define DCCP_SOCKOPT_CHANGE_R           4
 207 #define DCCP_SOCKOPT_GET_CUR_MPS        5
 208 #define DCCP_SOCKOPT_SEND_CSCOV         10
 209 #define DCCP_SOCKOPT_RECV_CSCOV         11
 210 #define DCCP_SOCKOPT_CCID_RX_INFO       128
 211 #define DCCP_SOCKOPT_CCID_TX_INFO       192
 212
 213 /* maximum number of services provided on the same listening port */
 214 #define DCCP_SERVICE_LIST_MAX_LEN      32
 215
 216 #ifdef __KERNEL__
 217
 218 #include <linux/in.h>
 219 #include <linux/ktime.h>
 220 #include <linux/list.h>
 221 #include <linux/uio.h>
 222 #include <linux/workqueue.h>
 223
 224 #include <net/inet_connection_sock.h>
 225 #include <net/inet_sock.h>
 226 #include <net/inet_timewait_sock.h>
 227 #include <net/tcp_states.h>
 228
 229 enum dccp_state {
 230         DCCP_OPEN       = TCP_ESTABLISHED,
 231         DCCP_REQUESTING = TCP_SYN_SENT,
 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_PARTOPEN   = TCP_MAX_STATES,
 238         DCCP_MAX_STATES
 239 };
 240
 241 #define DCCP_STATE_MASK 0xf
 242 #define DCCP_ACTION_FIN (1<<7)
 243
 244 enum {
 245         DCCPF_OPEN       = TCPF_ESTABLISHED,
 246         DCCPF_REQUESTING = TCPF_SYN_SENT,
 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         DCCPF_PARTOPEN   = 1 << DCCP_PARTOPEN,
 253 };
 254
 255 static inline struct dccp_hdr *dccp_hdr(const struct sk_buff *skb)
 256 {
 257         return (struct dccp_hdr *)skb_transport_header(skb);
 258 }
 259
 260 static inline struct dccp_hdr *dccp_zeroed_hdr(struct sk_buff *skb, int headlen)
 261 {
 262         skb_push(skb, headlen);
 263         skb_reset_transport_header(skb);
 264         return memset(skb_transport_header(skb), 0, headlen);
 265 }
 266
 267 static inline struct dccp_hdr_ext *dccp_hdrx(const struct dccp_hdr *dh)
 268 {
 269         return (struct dccp_hdr_ext *)((unsigned char *)dh + sizeof(*dh));
 270 }
 271
 272 static inline unsigned int __dccp_basic_hdr_len(const struct dccp_hdr *dh)
 273 {
 274         return sizeof(*dh) + (dh->dccph_x ? sizeof(struct dccp_hdr_ext) : 0);
 275 }
 276
 277 static inline unsigned int dccp_basic_hdr_len(const struct sk_buff *skb)
 278 {
 279         const struct dccp_hdr *dh = dccp_hdr(skb);
 280         return __dccp_basic_hdr_len(dh);
 281 }
 282
 283 static inline __u64 dccp_hdr_seq(const struct dccp_hdr *dh)
 284 {
 285         __u64 seq_nr =  ntohs(dh->dccph_seq);
 286
 287         if (dh->dccph_x != 0)
 288                 seq_nr = (seq_nr << 32) + ntohl(dccp_hdrx(dh)->dccph_seq_low);
 289         else
 290                 seq_nr += (u32)dh->dccph_seq2 << 16;
 291
 292         return seq_nr;
 293 }
 294
 295 static inline struct dccp_hdr_request *dccp_hdr_request(struct sk_buff *skb)
 296 {
 297         return (struct dccp_hdr_request *)(skb_transport_header(skb) +
 298                                            dccp_basic_hdr_len(skb));
 299 }
 300
 301 static inline struct dccp_hdr_ack_bits *dccp_hdr_ack_bits(const struct sk_buff *skb)
 302 {
 303         return (struct dccp_hdr_ack_bits *)(skb_transport_header(skb) +
 304                                             dccp_basic_hdr_len(skb));
 305 }
 306
 307 static inline u64 dccp_hdr_ack_seq(const struct sk_buff *skb)
 308 {
 309         const struct dccp_hdr_ack_bits *dhack = dccp_hdr_ack_bits(skb);
 310         return ((u64)ntohs(dhack->dccph_ack_nr_high) << 32) + ntohl(dhack->dccph_ack_nr_low);
 311 }
 312
 313 static inline struct dccp_hdr_response *dccp_hdr_response(struct sk_buff *skb)
 314 {
 315         return (struct dccp_hdr_response *)(skb_transport_header(skb) +
 316                                             dccp_basic_hdr_len(skb));
 317 }
 318
 319 static inline struct dccp_hdr_reset *dccp_hdr_reset(struct sk_buff *skb)
 320 {
 321         return (struct dccp_hdr_reset *)(skb_transport_header(skb) +
 322                                          dccp_basic_hdr_len(skb));
 323 }
 324
 325 static inline unsigned int __dccp_hdr_len(const struct dccp_hdr *dh)
 326 {
 327         return __dccp_basic_hdr_len(dh) +
 328                dccp_packet_hdr_len(dh->dccph_type);
 329 }
 330
 331 static inline unsigned int dccp_hdr_len(const struct sk_buff *skb)
 332 {
 333         return __dccp_hdr_len(dccp_hdr(skb));
 334 }
 335
 336
 337 /* initial values for each feature */
 338 #define DCCPF_INITIAL_SEQUENCE_WINDOW           100
 339 #define DCCPF_INITIAL_ACK_RATIO                 2
 340 #define DCCPF_INITIAL_CCID                      DCCPC_CCID2
 341 #define DCCPF_INITIAL_SEND_ACK_VECTOR           1
 342 /* FIXME: for now we're default to 1 but it should really be 0 */
 343 #define DCCPF_INITIAL_SEND_NDP_COUNT            1
 344
 345 #define DCCP_NDP_LIMIT 0xFFFFFF
 346
 347 /**
 348   * struct dccp_minisock - Minimal DCCP connection representation
 349   *
 350   * Will be used to pass the state from dccp_request_sock to dccp_sock.
 351   *
 352   * @dccpms_sequence_window - Sequence Window Feature (section 7.5.2)
 353   * @dccpms_ccid - Congestion Control Id (CCID) (section 10)
 354   * @dccpms_send_ack_vector - Send Ack Vector Feature (section 11.5)
 355   * @dccpms_send_ndp_count - Send NDP Count Feature (7.7.2)
 356   * @dccpms_ack_ratio - Ack Ratio Feature (section 11.3)
 357   * @dccpms_pending - List of features being negotiated
 358   * @dccpms_conf -
 359   */
 360 struct dccp_minisock {
 361         __u64                   dccpms_sequence_window;
 362         __u8                    dccpms_rx_ccid;
 363         __u8                    dccpms_tx_ccid;
 364         __u8                    dccpms_send_ack_vector;
 365         __u8                    dccpms_send_ndp_count;
 366         __u8                    dccpms_ack_ratio;
 367         struct list_head        dccpms_pending;
 368         struct list_head        dccpms_conf;
 369 };
 370
 371 struct dccp_opt_conf {
 372         __u8                    *dccpoc_val;
 373         __u8                    dccpoc_len;
 374 };
 375
 376 struct dccp_opt_pend {
 377         struct list_head        dccpop_node;
 378         __u8                    dccpop_type;
 379         __u8                    dccpop_feat;
 380         __u8                    *dccpop_val;
 381         __u8                    dccpop_len;
 382         int                     dccpop_conf;
 383         struct dccp_opt_conf    *dccpop_sc;
 384 };
 385
 386 extern void dccp_minisock_init(struct dccp_minisock *dmsk);
 387
 388 extern int dccp_parse_options(struct sock *sk, struct sk_buff *skb);
 389
 390 struct dccp_request_sock {
 391         struct inet_request_sock dreq_inet_rsk;
 392         __u64                    dreq_iss;
 393         __u64                    dreq_isr;
 394         __be32                   dreq_service;
 395 };
 396
 397 static inline struct dccp_request_sock *dccp_rsk(const struct request_sock *req)
 398 {
 399         return (struct dccp_request_sock *)req;
 400 }
 401
 402 extern struct inet_timewait_death_row dccp_death_row;
 403
 404 struct dccp_options_received {
 405         u32     dccpor_ndp; /* only 24 bits */
 406         u32     dccpor_timestamp;
 407         u32     dccpor_timestamp_echo;
 408         u32     dccpor_elapsed_time;
 409 };
 410
 411 struct ccid;
 412
 413 enum dccp_role {
 414         DCCP_ROLE_UNDEFINED,
 415         DCCP_ROLE_LISTEN,
 416         DCCP_ROLE_CLIENT,
 417         DCCP_ROLE_SERVER,
 418 };
 419
 420 struct dccp_service_list {
 421         __u32   dccpsl_nr;
 422         __be32  dccpsl_list[0];
 423 };
 424
 425 #define DCCP_SERVICE_INVALID_VALUE htonl((__u32)-1)
 426 #define DCCP_SERVICE_CODE_IS_ABSENT             0
 427
 428 static inline int dccp_list_has_service(const struct dccp_service_list *sl,
 429                                         const __be32 service)
 430 {
 431         if (likely(sl != NULL)) {
 432                 u32 i = sl->dccpsl_nr;
 433                 while (i--)
 434                         if (sl->dccpsl_list[i] == service)
 435                                 return 1;
 436         }
 437         return 0;
 438 }
 439
 440 struct dccp_ackvec;
 441
 442 /**
 443  * struct dccp_sock - DCCP socket state
 444  *
 445  * @dccps_swl - sequence number window low
 446  * @dccps_swh - sequence number window high
 447  * @dccps_awl - acknowledgement number window low
 448  * @dccps_awh - acknowledgement number window high
 449  * @dccps_iss - initial sequence number sent
 450  * @dccps_isr - initial sequence number received
 451  * @dccps_osr - first OPEN sequence number received
 452  * @dccps_gss - greatest sequence number sent
 453  * @dccps_gsr - greatest valid sequence number received
 454  * @dccps_gar - greatest valid ack number received on a non-Sync; initialized to %dccps_iss
 455  * @dccps_service - first (passive sock) or unique (active sock) service code
 456  * @dccps_service_list - second .. last service code on passive socket
 457  * @dccps_timestamp_time - time of latest TIMESTAMP option
 458  * @dccps_timestamp_echo - latest timestamp received on a TIMESTAMP option
 459  * @dccps_l_ack_ratio - feature-local Ack Ratio
 460  * @dccps_r_ack_ratio - feature-remote Ack Ratio
 461  * @dccps_pcslen - sender   partial checksum coverage (via sockopt)
 462  * @dccps_pcrlen - receiver partial checksum coverage (via sockopt)
 463  * @dccps_ndp_count - number of Non Data Packets since last data packet
 464  * @dccps_mss_cache - current value of MSS (path MTU minus header sizes)
 465  * @dccps_rate_last - timestamp for rate-limiting DCCP-Sync (RFC 4340, 7.5.4)
 466  * @dccps_minisock - associated minisock (accessed via dccp_msk)
 467  * @dccps_hc_rx_ackvec - rx half connection ack vector
 468  * @dccps_hc_rx_ccid - CCID used for the receiver (or receiving half-connection)
 469  * @dccps_hc_tx_ccid - CCID used for the sender (or sending half-connection)
 470  * @dccps_options_received - parsed set of retrieved options
 471  * @dccps_role - role of this sock, one of %dccp_role
 472  * @dccps_hc_rx_insert_options - receiver wants to add options when acking
 473  * @dccps_hc_tx_insert_options - sender wants to add options when sending
 474  * @dccps_xmit_timer - timer for when CCID is not ready to send
 475  * @dccps_syn_rtt - RTT sample from Request/Response exchange (in usecs)
 476  */
 477 struct dccp_sock {
 478         /* inet_connection_sock has to be the first member of dccp_sock */
 479         struct inet_connection_sock     dccps_inet_connection;
 480 #define dccps_syn_rtt                   dccps_inet_connection.icsk_ack.lrcvtime
 481         __u64                           dccps_swl;
 482         __u64                           dccps_swh;
 483         __u64                           dccps_awl;
 484         __u64                           dccps_awh;
 485         __u64                           dccps_iss;
 486         __u64                           dccps_isr;
 487         __u64                           dccps_osr;
 488         __u64                           dccps_gss;
 489         __u64                           dccps_gsr;
 490         __u64                           dccps_gar;
 491         __be32                          dccps_service;
 492         struct dccp_service_list        *dccps_service_list;
 493         ktime_t                         dccps_timestamp_time;
 494         __u32                           dccps_timestamp_echo;
 495         __u16                           dccps_l_ack_ratio;
 496         __u16                           dccps_r_ack_ratio;
 497         __u16                           dccps_pcslen;
 498         __u16                           dccps_pcrlen;
 499         unsigned long                   dccps_ndp_count;
 500         __u32                           dccps_mss_cache;
 501         unsigned long                   dccps_rate_last;
 502         struct dccp_minisock            dccps_minisock;
 503         struct dccp_ackvec              *dccps_hc_rx_ackvec;
 504         struct ccid                     *dccps_hc_rx_ccid;
 505         struct ccid                     *dccps_hc_tx_ccid;
 506         struct dccp_options_received    dccps_options_received;
 507         enum dccp_role                  dccps_role:2;
 508         __u8                            dccps_hc_rx_insert_options:1;
 509         __u8                            dccps_hc_tx_insert_options:1;
 510         struct timer_list               dccps_xmit_timer;
 511 };
 512
 513 static inline struct dccp_sock *dccp_sk(const struct sock *sk)
 514 {
 515         return (struct dccp_sock *)sk;
 516 }
 517
 518 static inline struct dccp_minisock *dccp_msk(const struct sock *sk)
 519 {
 520         return (struct dccp_minisock *)&dccp_sk(sk)->dccps_minisock;
 521 }
 522
 523 static inline const char *dccp_role(const struct sock *sk)
 524 {
 525         switch (dccp_sk(sk)->dccps_role) {
 526         case DCCP_ROLE_UNDEFINED: return "undefined";
 527         case DCCP_ROLE_LISTEN:    return "listen";
 528         case DCCP_ROLE_SERVER:    return "server";
 529         case DCCP_ROLE_CLIENT:    return "client";
 530         }
 531         return NULL;
 532 }
 533
 534 #endif /* __KERNEL__ */
 535
 536 #endif /* _LINUX_DCCP_H */