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_SERVER_TIMEWAIT 6 209 #define DCCP_SOCKOPT_SEND_CSCOV 10 210 #define DCCP_SOCKOPT_RECV_CSCOV 11 211 #define DCCP_SOCKOPT_CCID_RX_INFO 128 212 #define DCCP_SOCKOPT_CCID_TX_INFO 192 213 214 /* maximum number of services provided on the same listening port */ 215 #define DCCP_SERVICE_LIST_MAX_LEN 32 216 217 #ifdef __KERNEL__ 218 219 #include <linux/in.h> 220 #include <linux/ktime.h> 221 #include <linux/list.h> 222 #include <linux/uio.h> 223 #include <linux/workqueue.h> 224 225 #include <net/inet_connection_sock.h> 226 #include <net/inet_sock.h> 227 #include <net/inet_timewait_sock.h> 228 #include <net/tcp_states.h> 229 230 enum dccp_state { 231 DCCP_OPEN = TCP_ESTABLISHED, 232 DCCP_REQUESTING = TCP_SYN_SENT, 233 DCCP_LISTEN = TCP_LISTEN, 234 DCCP_RESPOND = TCP_SYN_RECV, 235 /* 236 * States involved in closing a DCCP connection: 237 * 1) ACTIVE_CLOSEREQ is entered by a server sending a CloseReq. 238 * 239 * 2) CLOSING can have three different meanings (RFC 4340, 8.3): 240 * a. Client has performed active-close, has sent a Close to the server 241 * from state OPEN or PARTOPEN, and is waiting for the final Reset 242 * (in this case, SOCK_DONE == 1). 243 * b. Client is asked to perform passive-close, by receiving a CloseReq 244 * in (PART)OPEN state. It sends a Close and waits for final Reset 245 * (in this case, SOCK_DONE == 0). 246 * c. Server performs an active-close as in (a), keeps TIMEWAIT state. 247 * 248 * 3) The following intermediate states are employed to give passively 249 * closing nodes a chance to process their unread data: 250 * - PASSIVE_CLOSE (from OPEN => CLOSED) and 251 * - PASSIVE_CLOSEREQ (from (PART)OPEN to CLOSING; case (b) above). 252 */ 253 DCCP_ACTIVE_CLOSEREQ = TCP_FIN_WAIT1, 254 DCCP_PASSIVE_CLOSE = TCP_CLOSE_WAIT, /* any node receiving a Close */ 255 DCCP_CLOSING = TCP_CLOSING, 256 DCCP_TIME_WAIT = TCP_TIME_WAIT, 257 DCCP_CLOSED = TCP_CLOSE, 258 DCCP_PARTOPEN = TCP_MAX_STATES, 259 DCCP_PASSIVE_CLOSEREQ, /* clients receiving CloseReq */ 260 DCCP_MAX_STATES 261 }; 262 263 #define DCCP_STATE_MASK 0x1f 264 265 enum { 266 DCCPF_OPEN = TCPF_ESTABLISHED, 267 DCCPF_REQUESTING = TCPF_SYN_SENT, 268 DCCPF_LISTEN = TCPF_LISTEN, 269 DCCPF_RESPOND = TCPF_SYN_RECV, 270 DCCPF_ACTIVE_CLOSEREQ = TCPF_FIN_WAIT1, 271 DCCPF_CLOSING = TCPF_CLOSING, 272 DCCPF_TIME_WAIT = TCPF_TIME_WAIT, 273 DCCPF_CLOSED = TCPF_CLOSE, 274 DCCPF_PARTOPEN = (1 << DCCP_PARTOPEN), 275 }; 276 277 static inline struct dccp_hdr *dccp_hdr(const struct sk_buff *skb) 278 { 279 return (struct dccp_hdr *)skb_transport_header(skb); 280 } 281 282 static inline struct dccp_hdr *dccp_zeroed_hdr(struct sk_buff *skb, int headlen) 283 { 284 skb_push(skb, headlen); 285 skb_reset_transport_header(skb); 286 return memset(skb_transport_header(skb), 0, headlen); 287 } 288 289 static inline struct dccp_hdr_ext *dccp_hdrx(const struct dccp_hdr *dh) 290 { 291 return (struct dccp_hdr_ext *)((unsigned char *)dh + sizeof(*dh)); 292 } 293 294 static inline unsigned int __dccp_basic_hdr_len(const struct dccp_hdr *dh) 295 { 296 return sizeof(*dh) + (dh->dccph_x ? sizeof(struct dccp_hdr_ext) : 0); 297 } 298 299 static inline unsigned int dccp_basic_hdr_len(const struct sk_buff *skb) 300 { 301 const struct dccp_hdr *dh = dccp_hdr(skb); 302 return __dccp_basic_hdr_len(dh); 303 } 304 305 static inline __u64 dccp_hdr_seq(const struct dccp_hdr *dh) 306 { 307 __u64 seq_nr = ntohs(dh->dccph_seq); 308 309 if (dh->dccph_x != 0) 310 seq_nr = (seq_nr << 32) + ntohl(dccp_hdrx(dh)->dccph_seq_low); 311 else 312 seq_nr += (u32)dh->dccph_seq2 << 16; 313 314 return seq_nr; 315 } 316 317 static inline struct dccp_hdr_request *dccp_hdr_request(struct sk_buff *skb) 318 { 319 return (struct dccp_hdr_request *)(skb_transport_header(skb) + 320 dccp_basic_hdr_len(skb)); 321 } 322 323 static inline struct dccp_hdr_ack_bits *dccp_hdr_ack_bits(const struct sk_buff *skb) 324 { 325 return (struct dccp_hdr_ack_bits *)(skb_transport_header(skb) + 326 dccp_basic_hdr_len(skb)); 327 } 328 329 static inline u64 dccp_hdr_ack_seq(const struct sk_buff *skb) 330 { 331 const struct dccp_hdr_ack_bits *dhack = dccp_hdr_ack_bits(skb); 332 return ((u64)ntohs(dhack->dccph_ack_nr_high) << 32) + ntohl(dhack->dccph_ack_nr_low); 333 } 334 335 static inline struct dccp_hdr_response *dccp_hdr_response(struct sk_buff *skb) 336 { 337 return (struct dccp_hdr_response *)(skb_transport_header(skb) + 338 dccp_basic_hdr_len(skb)); 339 } 340 341 static inline struct dccp_hdr_reset *dccp_hdr_reset(struct sk_buff *skb) 342 { 343 return (struct dccp_hdr_reset *)(skb_transport_header(skb) + 344 dccp_basic_hdr_len(skb)); 345 } 346 347 static inline unsigned int __dccp_hdr_len(const struct dccp_hdr *dh) 348 { 349 return __dccp_basic_hdr_len(dh) + 350 dccp_packet_hdr_len(dh->dccph_type); 351 } 352 353 static inline unsigned int dccp_hdr_len(const struct sk_buff *skb) 354 { 355 return __dccp_hdr_len(dccp_hdr(skb)); 356 } 357 358 359 /* initial values for each feature */ 360 #define DCCPF_INITIAL_SEQUENCE_WINDOW 100 361 #define DCCPF_INITIAL_ACK_RATIO 2 362 #define DCCPF_INITIAL_CCID DCCPC_CCID2 363 #define DCCPF_INITIAL_SEND_ACK_VECTOR 1 364 /* FIXME: for now we're default to 1 but it should really be 0 */ 365 #define DCCPF_INITIAL_SEND_NDP_COUNT 1 366 367 #define DCCP_NDP_LIMIT 0xFFFFFF 368 369 /** 370 * struct dccp_minisock - Minimal DCCP connection representation 371 * 372 * Will be used to pass the state from dccp_request_sock to dccp_sock. 373 * 374 * @dccpms_sequence_window - Sequence Window Feature (section 7.5.2) 375 * @dccpms_ccid - Congestion Control Id (CCID) (section 10) 376 * @dccpms_send_ack_vector - Send Ack Vector Feature (section 11.5) 377 * @dccpms_send_ndp_count - Send NDP Count Feature (7.7.2) 378 * @dccpms_ack_ratio - Ack Ratio Feature (section 11.3) 379 * @dccpms_pending - List of features being negotiated 380 * @dccpms_conf - 381 */ 382 struct dccp_minisock { 383 __u64 dccpms_sequence_window; 384 __u8 dccpms_rx_ccid; 385 __u8 dccpms_tx_ccid; 386 __u8 dccpms_send_ack_vector; 387 __u8 dccpms_send_ndp_count; 388 __u8 dccpms_ack_ratio; 389 struct list_head dccpms_pending; 390 struct list_head dccpms_conf; 391 }; 392 393 struct dccp_opt_conf { 394 __u8 *dccpoc_val; 395 __u8 dccpoc_len; 396 }; 397 398 struct dccp_opt_pend { 399 struct list_head dccpop_node; 400 __u8 dccpop_type; 401 __u8 dccpop_feat; 402 __u8 *dccpop_val; 403 __u8 dccpop_len; 404 int dccpop_conf; 405 struct dccp_opt_conf *dccpop_sc; 406 }; 407 408 extern void dccp_minisock_init(struct dccp_minisock *dmsk); 409 410 /** 411 * struct dccp_request_sock - represent DCCP-specific connection request 412 * @dreq_inet_rsk: structure inherited from 413 * @dreq_iss: initial sequence number sent on the Response (RFC 4340, 7.1) 414 * @dreq_isr: initial sequence number received on the Request 415 * @dreq_service: service code present on the Request (there is just one) 416 * The following two fields are analogous to the ones in dccp_sock: 417 * @dreq_timestamp_echo: last received timestamp to echo (13.1) 418 * @dreq_timestamp_echo: the time of receiving the last @dreq_timestamp_echo 419 */ 420 struct dccp_request_sock { 421 struct inet_request_sock dreq_inet_rsk; 422 __u64 dreq_iss; 423 __u64 dreq_isr; 424 __be32 dreq_service; 425 __u32 dreq_timestamp_echo; 426 __u32 dreq_timestamp_time; 427 }; 428 429 static inline struct dccp_request_sock *dccp_rsk(const struct request_sock *req) 430 { 431 return (struct dccp_request_sock *)req; 432 } 433 434 extern struct inet_timewait_death_row dccp_death_row; 435 436 extern int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq, 437 struct sk_buff *skb); 438 439 struct dccp_options_received { 440 u32 dccpor_ndp; /* only 24 bits */ 441 u32 dccpor_timestamp; 442 u32 dccpor_timestamp_echo; 443 u32 dccpor_elapsed_time; 444 }; 445 446 struct ccid; 447 448 enum dccp_role { 449 DCCP_ROLE_UNDEFINED, 450 DCCP_ROLE_LISTEN, 451 DCCP_ROLE_CLIENT, 452 DCCP_ROLE_SERVER, 453 }; 454 455 struct dccp_service_list { 456 __u32 dccpsl_nr; 457 __be32 dccpsl_list[0]; 458 }; 459 460 #define DCCP_SERVICE_INVALID_VALUE htonl((__u32)-1) 461 #define DCCP_SERVICE_CODE_IS_ABSENT 0 462 463 static inline int dccp_list_has_service(const struct dccp_service_list *sl, 464 const __be32 service) 465 { 466 if (likely(sl != NULL)) { 467 u32 i = sl->dccpsl_nr; 468 while (i--) 469 if (sl->dccpsl_list[i] == service) 470 return 1; 471 } 472 return 0; 473 } 474 475 struct dccp_ackvec; 476 477 /** 478 * struct dccp_sock - DCCP socket state 479 * 480 * @dccps_swl - sequence number window low 481 * @dccps_swh - sequence number window high 482 * @dccps_awl - acknowledgement number window low 483 * @dccps_awh - acknowledgement number window high 484 * @dccps_iss - initial sequence number sent 485 * @dccps_isr - initial sequence number received 486 * @dccps_osr - first OPEN sequence number received 487 * @dccps_gss - greatest sequence number sent 488 * @dccps_gsr - greatest valid sequence number received 489 * @dccps_gar - greatest valid ack number received on a non-Sync; initialized to %dccps_iss 490 * @dccps_service - first (passive sock) or unique (active sock) service code 491 * @dccps_service_list - second .. last service code on passive socket 492 * @dccps_timestamp_echo - latest timestamp received on a TIMESTAMP option 493 * @dccps_timestamp_time - time of receiving latest @dccps_timestamp_echo 494 * @dccps_l_ack_ratio - feature-local Ack Ratio 495 * @dccps_r_ack_ratio - feature-remote Ack Ratio 496 * @dccps_pcslen - sender partial checksum coverage (via sockopt) 497 * @dccps_pcrlen - receiver partial checksum coverage (via sockopt) 498 * @dccps_ndp_count - number of Non Data Packets since last data packet 499 * @dccps_mss_cache - current value of MSS (path MTU minus header sizes) 500 * @dccps_rate_last - timestamp for rate-limiting DCCP-Sync (RFC 4340, 7.5.4) 501 * @dccps_minisock - associated minisock (accessed via dccp_msk) 502 * @dccps_hc_rx_ackvec - rx half connection ack vector 503 * @dccps_hc_rx_ccid - CCID used for the receiver (or receiving half-connection) 504 * @dccps_hc_tx_ccid - CCID used for the sender (or sending half-connection) 505 * @dccps_options_received - parsed set of retrieved options 506 * @dccps_role - role of this sock, one of %dccp_role 507 * @dccps_hc_rx_insert_options - receiver wants to add options when acking 508 * @dccps_hc_tx_insert_options - sender wants to add options when sending 509 * @dccps_server_timewait - server holds timewait state on close (RFC 4340, 8.3) 510 * @dccps_xmit_timer - timer for when CCID is not ready to send 511 * @dccps_syn_rtt - RTT sample from Request/Response exchange (in usecs) 512 */ 513 struct dccp_sock { 514 /* inet_connection_sock has to be the first member of dccp_sock */ 515 struct inet_connection_sock dccps_inet_connection; 516 #define dccps_syn_rtt dccps_inet_connection.icsk_ack.lrcvtime 517 __u64 dccps_swl; 518 __u64 dccps_swh; 519 __u64 dccps_awl; 520 __u64 dccps_awh; 521 __u64 dccps_iss; 522 __u64 dccps_isr; 523 __u64 dccps_osr; 524 __u64 dccps_gss; 525 __u64 dccps_gsr; 526 __u64 dccps_gar; 527 __be32 dccps_service; 528 __u32 dccps_mss_cache; 529 struct dccp_service_list *dccps_service_list; 530 __u32 dccps_timestamp_echo; 531 __u32 dccps_timestamp_time; 532 __u16 dccps_l_ack_ratio; 533 __u16 dccps_r_ack_ratio; 534 __u16 dccps_pcslen; 535 __u16 dccps_pcrlen; 536 unsigned long dccps_ndp_count; 537 unsigned long dccps_rate_last; 538 struct dccp_minisock dccps_minisock; 539 struct dccp_ackvec *dccps_hc_rx_ackvec; 540 struct ccid *dccps_hc_rx_ccid; 541 struct ccid *dccps_hc_tx_ccid; 542 struct dccp_options_received dccps_options_received; 543 enum dccp_role dccps_role:2; 544 __u8 dccps_hc_rx_insert_options:1; 545 __u8 dccps_hc_tx_insert_options:1; 546 __u8 dccps_server_timewait:1; 547 struct timer_list dccps_xmit_timer; 548 }; 549 550 static inline struct dccp_sock *dccp_sk(const struct sock *sk) 551 { 552 return (struct dccp_sock *)sk; 553 } 554 555 static inline struct dccp_minisock *dccp_msk(const struct sock *sk) 556 { 557 return (struct dccp_minisock *)&dccp_sk(sk)->dccps_minisock; 558 } 559 560 static inline const char *dccp_role(const struct sock *sk) 561 { 562 switch (dccp_sk(sk)->dccps_role) { 563 case DCCP_ROLE_UNDEFINED: return "undefined"; 564 case DCCP_ROLE_LISTEN: return "listen"; 565 case DCCP_ROLE_SERVER: return "server"; 566 case DCCP_ROLE_CLIENT: return "client"; 567 } 568 return NULL; 569 } 570 571 #endif /* __KERNEL__ */ 572 573 #endif /* _LINUX_DCCP_H */ 574