1 #ifndef _DCCP_H 2 #define _DCCP_H 3 /* 4 * net/dccp/dccp.h 5 * 6 * An implementation of the DCCP protocol 7 * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br> 8 * Copyright (c) 2005 Ian McDonald <iam4@cs.waikato.ac.nz> 9 * 10 * This program is free software; you can redistribute it and/or modify it 11 * under the terms of the GNU General Public License version 2 as 12 * published by the Free Software Foundation. 13 */ 14 15 #include <linux/config.h> 16 #include <linux/dccp.h> 17 #include <net/snmp.h> 18 #include <net/sock.h> 19 #include <net/tcp.h> 20 #include "ackvec.h" 21 22 #ifdef CONFIG_IP_DCCP_DEBUG 23 extern int dccp_debug; 24 25 #define dccp_pr_debug(format, a...) \ 26 do { if (dccp_debug) \ 27 printk(KERN_DEBUG "%s: " format, __FUNCTION__ , ##a); \ 28 } while (0) 29 #define dccp_pr_debug_cat(format, a...) do { if (dccp_debug) \ 30 printk(format, ##a); } while (0) 31 #else 32 #define dccp_pr_debug(format, a...) 33 #define dccp_pr_debug_cat(format, a...) 34 #endif 35 36 extern struct inet_hashinfo dccp_hashinfo; 37 38 extern atomic_t dccp_orphan_count; 39 extern int dccp_tw_count; 40 extern void dccp_tw_deschedule(struct inet_timewait_sock *tw); 41 42 extern void dccp_time_wait(struct sock *sk, int state, int timeo); 43 44 /* FIXME: Right size this */ 45 #define DCCP_MAX_OPT_LEN 128 46 47 #define DCCP_MAX_PACKET_HDR 32 48 49 #define MAX_DCCP_HEADER (DCCP_MAX_PACKET_HDR + DCCP_MAX_OPT_LEN + MAX_HEADER) 50 51 #define DCCP_TIMEWAIT_LEN (60 * HZ) /* how long to wait to destroy TIME-WAIT 52 * state, about 60 seconds */ 53 54 /* draft-ietf-dccp-spec-11.txt initial RTO value */ 55 #define DCCP_TIMEOUT_INIT ((unsigned)(3 * HZ)) 56 57 /* Maximal interval between probes for local resources. */ 58 #define DCCP_RESOURCE_PROBE_INTERVAL ((unsigned)(HZ / 2U)) 59 60 #define DCCP_RTO_MAX ((unsigned)(120 * HZ)) /* FIXME: using TCP value */ 61 62 extern struct proto dccp_v4_prot; 63 64 /* is seq1 < seq2 ? */ 65 static inline int before48(const u64 seq1, const u64 seq2) 66 { 67 return (s64)((seq1 << 16) - (seq2 << 16)) < 0; 68 } 69 70 /* is seq1 > seq2 ? */ 71 static inline int after48(const u64 seq1, const u64 seq2) 72 { 73 return (s64)((seq2 << 16) - (seq1 << 16)) < 0; 74 } 75 76 /* is seq2 <= seq1 <= seq3 ? */ 77 static inline int between48(const u64 seq1, const u64 seq2, const u64 seq3) 78 { 79 return (seq3 << 16) - (seq2 << 16) >= (seq1 << 16) - (seq2 << 16); 80 } 81 82 static inline u64 max48(const u64 seq1, const u64 seq2) 83 { 84 return after48(seq1, seq2) ? seq1 : seq2; 85 } 86 87 enum { 88 DCCP_MIB_NUM = 0, 89 DCCP_MIB_ACTIVEOPENS, /* ActiveOpens */ 90 DCCP_MIB_ESTABRESETS, /* EstabResets */ 91 DCCP_MIB_CURRESTAB, /* CurrEstab */ 92 DCCP_MIB_OUTSEGS, /* OutSegs */ 93 DCCP_MIB_OUTRSTS, 94 DCCP_MIB_ABORTONTIMEOUT, 95 DCCP_MIB_TIMEOUTS, 96 DCCP_MIB_ABORTFAILED, 97 DCCP_MIB_PASSIVEOPENS, 98 DCCP_MIB_ATTEMPTFAILS, 99 DCCP_MIB_OUTDATAGRAMS, 100 DCCP_MIB_INERRS, 101 DCCP_MIB_OPTMANDATORYERROR, 102 DCCP_MIB_INVALIDOPT, 103 __DCCP_MIB_MAX 104 }; 105 106 #define DCCP_MIB_MAX __DCCP_MIB_MAX 107 struct dccp_mib { 108 unsigned long mibs[DCCP_MIB_MAX]; 109 } __SNMP_MIB_ALIGN__; 110 111 DECLARE_SNMP_STAT(struct dccp_mib, dccp_statistics); 112 #define DCCP_INC_STATS(field) SNMP_INC_STATS(dccp_statistics, field) 113 #define DCCP_INC_STATS_BH(field) SNMP_INC_STATS_BH(dccp_statistics, field) 114 #define DCCP_INC_STATS_USER(field) SNMP_INC_STATS_USER(dccp_statistics, field) 115 #define DCCP_DEC_STATS(field) SNMP_DEC_STATS(dccp_statistics, field) 116 #define DCCP_ADD_STATS_BH(field, val) \ 117 SNMP_ADD_STATS_BH(dccp_statistics, field, val) 118 #define DCCP_ADD_STATS_USER(field, val) \ 119 SNMP_ADD_STATS_USER(dccp_statistics, field, val) 120 121 extern int dccp_retransmit_skb(struct sock *sk, struct sk_buff *skb); 122 123 extern int dccp_send_response(struct sock *sk); 124 extern void dccp_send_ack(struct sock *sk); 125 extern void dccp_send_delayed_ack(struct sock *sk); 126 extern void dccp_send_sync(struct sock *sk, const u64 seq, 127 const enum dccp_pkt_type pkt_type); 128 129 extern int dccp_write_xmit(struct sock *sk, struct sk_buff *skb, long *timeo); 130 extern void dccp_write_space(struct sock *sk); 131 132 extern void dccp_init_xmit_timers(struct sock *sk); 133 static inline void dccp_clear_xmit_timers(struct sock *sk) 134 { 135 inet_csk_clear_xmit_timers(sk); 136 } 137 138 extern unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu); 139 140 extern const char *dccp_packet_name(const int type); 141 extern const char *dccp_state_name(const int state); 142 143 static inline void dccp_set_state(struct sock *sk, const int state) 144 { 145 const int oldstate = sk->sk_state; 146 147 dccp_pr_debug("%s(%p) %-10.10s -> %s\n", 148 dccp_role(sk), sk, 149 dccp_state_name(oldstate), dccp_state_name(state)); 150 WARN_ON(state == oldstate); 151 152 switch (state) { 153 case DCCP_OPEN: 154 if (oldstate != DCCP_OPEN) 155 DCCP_INC_STATS(DCCP_MIB_CURRESTAB); 156 break; 157 158 case DCCP_CLOSED: 159 if (oldstate == DCCP_CLOSING || oldstate == DCCP_OPEN) 160 DCCP_INC_STATS(DCCP_MIB_ESTABRESETS); 161 162 sk->sk_prot->unhash(sk); 163 if (inet_csk(sk)->icsk_bind_hash != NULL && 164 !(sk->sk_userlocks & SOCK_BINDPORT_LOCK)) 165 inet_put_port(&dccp_hashinfo, sk); 166 /* fall through */ 167 default: 168 if (oldstate == DCCP_OPEN) 169 DCCP_DEC_STATS(DCCP_MIB_CURRESTAB); 170 } 171 172 /* Change state AFTER socket is unhashed to avoid closed 173 * socket sitting in hash tables. 174 */ 175 sk->sk_state = state; 176 } 177 178 static inline void dccp_done(struct sock *sk) 179 { 180 dccp_set_state(sk, DCCP_CLOSED); 181 dccp_clear_xmit_timers(sk); 182 183 sk->sk_shutdown = SHUTDOWN_MASK; 184 185 if (!sock_flag(sk, SOCK_DEAD)) 186 sk->sk_state_change(sk); 187 else 188 inet_csk_destroy_sock(sk); 189 } 190 191 static inline void dccp_openreq_init(struct request_sock *req, 192 struct dccp_sock *dp, 193 struct sk_buff *skb) 194 { 195 /* 196 * FIXME: fill in the other req fields from the DCCP options 197 * received 198 */ 199 inet_rsk(req)->rmt_port = dccp_hdr(skb)->dccph_sport; 200 inet_rsk(req)->acked = 0; 201 req->rcv_wnd = 0; 202 } 203 204 extern int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb); 205 206 extern struct sock *dccp_create_openreq_child(struct sock *sk, 207 const struct request_sock *req, 208 const struct sk_buff *skb); 209 210 extern int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb); 211 212 extern void dccp_v4_err(struct sk_buff *skb, u32); 213 214 extern int dccp_v4_rcv(struct sk_buff *skb); 215 216 extern struct sock *dccp_v4_request_recv_sock(struct sock *sk, 217 struct sk_buff *skb, 218 struct request_sock *req, 219 struct dst_entry *dst); 220 extern struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb, 221 struct request_sock *req, 222 struct request_sock **prev); 223 224 extern int dccp_child_process(struct sock *parent, struct sock *child, 225 struct sk_buff *skb); 226 extern int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, 227 struct dccp_hdr *dh, unsigned len); 228 extern int dccp_rcv_established(struct sock *sk, struct sk_buff *skb, 229 const struct dccp_hdr *dh, const unsigned len); 230 231 extern void dccp_close(struct sock *sk, long timeout); 232 extern struct sk_buff *dccp_make_response(struct sock *sk, 233 struct dst_entry *dst, 234 struct request_sock *req); 235 extern struct sk_buff *dccp_make_reset(struct sock *sk, 236 struct dst_entry *dst, 237 enum dccp_reset_codes code); 238 239 extern int dccp_connect(struct sock *sk); 240 extern int dccp_disconnect(struct sock *sk, int flags); 241 extern int dccp_getsockopt(struct sock *sk, int level, int optname, 242 char __user *optval, int __user *optlen); 243 extern int dccp_setsockopt(struct sock *sk, int level, int optname, 244 char __user *optval, int optlen); 245 extern int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg); 246 extern int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, 247 struct msghdr *msg, size_t size); 248 extern int dccp_recvmsg(struct kiocb *iocb, struct sock *sk, 249 struct msghdr *msg, size_t len, int nonblock, 250 int flags, int *addr_len); 251 extern void dccp_shutdown(struct sock *sk, int how); 252 253 extern int dccp_v4_checksum(const struct sk_buff *skb, 254 const u32 saddr, const u32 daddr); 255 256 extern int dccp_v4_send_reset(struct sock *sk, 257 enum dccp_reset_codes code); 258 extern void dccp_send_close(struct sock *sk, const int active); 259 260 struct dccp_skb_cb { 261 __u8 dccpd_type:4; 262 __u8 dccpd_ccval:4; 263 __u8 dccpd_reset_code; 264 __u16 dccpd_opt_len; 265 __u64 dccpd_seq; 266 __u64 dccpd_ack_seq; 267 }; 268 269 #define DCCP_SKB_CB(__skb) ((struct dccp_skb_cb *)&((__skb)->cb[0])) 270 271 static inline int dccp_non_data_packet(const struct sk_buff *skb) 272 { 273 const __u8 type = DCCP_SKB_CB(skb)->dccpd_type; 274 275 return type == DCCP_PKT_ACK || 276 type == DCCP_PKT_CLOSE || 277 type == DCCP_PKT_CLOSEREQ || 278 type == DCCP_PKT_RESET || 279 type == DCCP_PKT_SYNC || 280 type == DCCP_PKT_SYNCACK; 281 } 282 283 static inline int dccp_packet_without_ack(const struct sk_buff *skb) 284 { 285 const __u8 type = DCCP_SKB_CB(skb)->dccpd_type; 286 287 return type == DCCP_PKT_DATA || type == DCCP_PKT_REQUEST; 288 } 289 290 #define DCCP_MAX_SEQNO ((((u64)1) << 48) - 1) 291 #define DCCP_PKT_WITHOUT_ACK_SEQ (DCCP_MAX_SEQNO << 2) 292 293 static inline void dccp_set_seqno(u64 *seqno, u64 value) 294 { 295 if (value > DCCP_MAX_SEQNO) 296 value -= DCCP_MAX_SEQNO + 1; 297 *seqno = value; 298 } 299 300 static inline u64 dccp_delta_seqno(u64 seqno1, u64 seqno2) 301 { 302 return ((seqno2 << 16) - (seqno1 << 16)) >> 16; 303 } 304 305 static inline void dccp_inc_seqno(u64 *seqno) 306 { 307 if (++*seqno > DCCP_MAX_SEQNO) 308 *seqno = 0; 309 } 310 311 static inline void dccp_hdr_set_seq(struct dccp_hdr *dh, const u64 gss) 312 { 313 struct dccp_hdr_ext *dhx = (struct dccp_hdr_ext *)((void *)dh + 314 sizeof(*dh)); 315 316 #if defined(__LITTLE_ENDIAN_BITFIELD) 317 dh->dccph_seq = htonl((gss >> 32)) >> 8; 318 #elif defined(__BIG_ENDIAN_BITFIELD) 319 dh->dccph_seq = htonl((gss >> 32)); 320 #else 321 #error "Adjust your <asm/byteorder.h> defines" 322 #endif 323 dhx->dccph_seq_low = htonl(gss & 0xffffffff); 324 } 325 326 static inline void dccp_hdr_set_ack(struct dccp_hdr_ack_bits *dhack, 327 const u64 gsr) 328 { 329 #if defined(__LITTLE_ENDIAN_BITFIELD) 330 dhack->dccph_ack_nr_high = htonl((gsr >> 32)) >> 8; 331 #elif defined(__BIG_ENDIAN_BITFIELD) 332 dhack->dccph_ack_nr_high = htonl((gsr >> 32)); 333 #else 334 #error "Adjust your <asm/byteorder.h> defines" 335 #endif 336 dhack->dccph_ack_nr_low = htonl(gsr & 0xffffffff); 337 } 338 339 static inline void dccp_update_gsr(struct sock *sk, u64 seq) 340 { 341 struct dccp_sock *dp = dccp_sk(sk); 342 343 dp->dccps_gsr = seq; 344 dccp_set_seqno(&dp->dccps_swl, 345 (dp->dccps_gsr + 1 - 346 (dp->dccps_options.dccpo_sequence_window / 4))); 347 dccp_set_seqno(&dp->dccps_swh, 348 (dp->dccps_gsr + 349 (3 * dp->dccps_options.dccpo_sequence_window) / 4)); 350 } 351 352 static inline void dccp_update_gss(struct sock *sk, u64 seq) 353 { 354 struct dccp_sock *dp = dccp_sk(sk); 355 356 dp->dccps_awh = dp->dccps_gss = seq; 357 dccp_set_seqno(&dp->dccps_awl, 358 (dp->dccps_gss - 359 dp->dccps_options.dccpo_sequence_window + 1)); 360 } 361 362 static inline int dccp_ack_pending(const struct sock *sk) 363 { 364 const struct dccp_sock *dp = dccp_sk(sk); 365 return dp->dccps_timestamp_echo != 0 || 366 #ifdef CONFIG_IP_DCCP_ACKVEC 367 (dp->dccps_options.dccpo_send_ack_vector && 368 dccp_ackvec_pending(dp->dccps_hc_rx_ackvec)) || 369 #endif 370 inet_csk_ack_scheduled(sk); 371 } 372 373 extern void dccp_insert_options(struct sock *sk, struct sk_buff *skb); 374 extern void dccp_insert_option_elapsed_time(struct sock *sk, 375 struct sk_buff *skb, 376 u32 elapsed_time); 377 extern void dccp_insert_option_timestamp(struct sock *sk, 378 struct sk_buff *skb); 379 extern void dccp_insert_option(struct sock *sk, struct sk_buff *skb, 380 unsigned char option, 381 const void *value, unsigned char len); 382 383 extern struct socket *dccp_ctl_socket; 384 385 extern void dccp_timestamp(const struct sock *sk, struct timeval *tv); 386 387 static inline suseconds_t timeval_usecs(const struct timeval *tv) 388 { 389 return tv->tv_sec * USEC_PER_SEC + tv->tv_usec; 390 } 391 392 static inline suseconds_t timeval_delta(const struct timeval *large, 393 const struct timeval *small) 394 { 395 time_t secs = large->tv_sec - small->tv_sec; 396 suseconds_t usecs = large->tv_usec - small->tv_usec; 397 398 if (usecs < 0) { 399 secs--; 400 usecs += USEC_PER_SEC; 401 } 402 return secs * USEC_PER_SEC + usecs; 403 } 404 405 static inline void timeval_add_usecs(struct timeval *tv, 406 const suseconds_t usecs) 407 { 408 tv->tv_usec += usecs; 409 while (tv->tv_usec >= USEC_PER_SEC) { 410 tv->tv_sec++; 411 tv->tv_usec -= USEC_PER_SEC; 412 } 413 } 414 415 static inline void timeval_sub_usecs(struct timeval *tv, 416 const suseconds_t usecs) 417 { 418 tv->tv_usec -= usecs; 419 while (tv->tv_usec < 0) { 420 tv->tv_sec--; 421 tv->tv_usec += USEC_PER_SEC; 422 } 423 } 424 425 #endif /* _DCCP_H */ 426