dccp.h revision 2e2e9e92bd723244ea20fa488b1780111f2b05e1
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) 2005-6 Ian McDonald <ian.mcdonald@jandi.co.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/dccp.h> 16#include <net/snmp.h> 17#include <net/sock.h> 18#include <net/tcp.h> 19#include "ackvec.h" 20 21#ifdef CONFIG_IP_DCCP_DEBUG 22extern int dccp_debug; 23 24#define dccp_pr_debug(format, a...) \ 25 do { if (dccp_debug) \ 26 printk(KERN_DEBUG "%s: " format, __FUNCTION__ , ##a); \ 27 } while (0) 28#define dccp_pr_debug_cat(format, a...) do { if (dccp_debug) \ 29 printk(format, ##a); } while (0) 30#else 31#define dccp_pr_debug(format, a...) 32#define dccp_pr_debug_cat(format, a...) 33#endif 34 35extern struct inet_hashinfo dccp_hashinfo; 36 37extern atomic_t dccp_orphan_count; 38 39extern void dccp_time_wait(struct sock *sk, int state, int timeo); 40 41/* 42 * Set safe upper bounds for header and option length. Since Data Offset is 8 43 * bits (RFC 4340, sec. 5.1), the total header length can never be more than 44 * 4 * 255 = 1020 bytes. The largest possible header length is 28 bytes (X=1): 45 * - DCCP-Response with ACK Subheader and 4 bytes of Service code OR 46 * - DCCP-Reset with ACK Subheader and 4 bytes of Reset Code fields 47 * Hence a safe upper bound for the maximum option length is 1020-28 = 992 48 */ 49#define MAX_DCCP_SPECIFIC_HEADER (255 * sizeof(int)) 50#define DCCP_MAX_PACKET_HDR 28 51#define DCCP_MAX_OPT_LEN (MAX_DCCP_SPECIFIC_HEADER - DCCP_MAX_PACKET_HDR) 52#define MAX_DCCP_HEADER (MAX_DCCP_SPECIFIC_HEADER + MAX_HEADER) 53 54#define DCCP_TIMEWAIT_LEN (60 * HZ) /* how long to wait to destroy TIME-WAIT 55 * state, about 60 seconds */ 56 57/* RFC 1122, 4.2.3.1 initial RTO value */ 58#define DCCP_TIMEOUT_INIT ((unsigned)(3 * HZ)) 59 60/* Maximal interval between probes for local resources. */ 61#define DCCP_RESOURCE_PROBE_INTERVAL ((unsigned)(HZ / 2U)) 62 63#define DCCP_RTO_MAX ((unsigned)(120 * HZ)) /* FIXME: using TCP value */ 64 65#define DCCP_XMIT_TIMEO 30000 /* Time/msecs for blocking transmit per packet */ 66 67/* sysctl variables for DCCP */ 68extern int sysctl_dccp_request_retries; 69extern int sysctl_dccp_retries1; 70extern int sysctl_dccp_retries2; 71extern int dccp_feat_default_sequence_window; 72extern int dccp_feat_default_rx_ccid; 73extern int dccp_feat_default_tx_ccid; 74extern int dccp_feat_default_ack_ratio; 75extern int dccp_feat_default_send_ack_vector; 76extern int dccp_feat_default_send_ndp_count; 77 78/* is seq1 < seq2 ? */ 79static inline int before48(const u64 seq1, const u64 seq2) 80{ 81 return (s64)((seq1 << 16) - (seq2 << 16)) < 0; 82} 83 84/* is seq1 > seq2 ? */ 85static inline int after48(const u64 seq1, const u64 seq2) 86{ 87 return (s64)((seq2 << 16) - (seq1 << 16)) < 0; 88} 89 90/* is seq2 <= seq1 <= seq3 ? */ 91static inline int between48(const u64 seq1, const u64 seq2, const u64 seq3) 92{ 93 return (seq3 << 16) - (seq2 << 16) >= (seq1 << 16) - (seq2 << 16); 94} 95 96static inline u64 max48(const u64 seq1, const u64 seq2) 97{ 98 return after48(seq1, seq2) ? seq1 : seq2; 99} 100 101/* is seq1 next seqno after seq2 */ 102static inline int follows48(const u64 seq1, const u64 seq2) 103{ 104 int diff = (seq1 & 0xFFFF) - (seq2 & 0xFFFF); 105 106 return diff==1; 107} 108 109enum { 110 DCCP_MIB_NUM = 0, 111 DCCP_MIB_ACTIVEOPENS, /* ActiveOpens */ 112 DCCP_MIB_ESTABRESETS, /* EstabResets */ 113 DCCP_MIB_CURRESTAB, /* CurrEstab */ 114 DCCP_MIB_OUTSEGS, /* OutSegs */ 115 DCCP_MIB_OUTRSTS, 116 DCCP_MIB_ABORTONTIMEOUT, 117 DCCP_MIB_TIMEOUTS, 118 DCCP_MIB_ABORTFAILED, 119 DCCP_MIB_PASSIVEOPENS, 120 DCCP_MIB_ATTEMPTFAILS, 121 DCCP_MIB_OUTDATAGRAMS, 122 DCCP_MIB_INERRS, 123 DCCP_MIB_OPTMANDATORYERROR, 124 DCCP_MIB_INVALIDOPT, 125 __DCCP_MIB_MAX 126}; 127 128#define DCCP_MIB_MAX __DCCP_MIB_MAX 129struct dccp_mib { 130 unsigned long mibs[DCCP_MIB_MAX]; 131} __SNMP_MIB_ALIGN__; 132 133DECLARE_SNMP_STAT(struct dccp_mib, dccp_statistics); 134#define DCCP_INC_STATS(field) SNMP_INC_STATS(dccp_statistics, field) 135#define DCCP_INC_STATS_BH(field) SNMP_INC_STATS_BH(dccp_statistics, field) 136#define DCCP_INC_STATS_USER(field) SNMP_INC_STATS_USER(dccp_statistics, field) 137#define DCCP_DEC_STATS(field) SNMP_DEC_STATS(dccp_statistics, field) 138#define DCCP_ADD_STATS_BH(field, val) \ 139 SNMP_ADD_STATS_BH(dccp_statistics, field, val) 140#define DCCP_ADD_STATS_USER(field, val) \ 141 SNMP_ADD_STATS_USER(dccp_statistics, field, val) 142 143/* 144 * Checksumming routines 145 */ 146static inline int dccp_csum_coverage(const struct sk_buff *skb) 147{ 148 const struct dccp_hdr* dh = dccp_hdr(skb); 149 150 if (dh->dccph_cscov == 0) 151 return skb->len; 152 return (dh->dccph_doff + dh->dccph_cscov - 1) * sizeof(u32); 153} 154 155static inline void dccp_csum_outgoing(struct sk_buff *skb) 156{ 157 int cov = dccp_csum_coverage(skb); 158 159 if (cov >= skb->len) 160 dccp_hdr(skb)->dccph_cscov = 0; 161 162 skb->csum = skb_checksum(skb, 0, (cov > skb->len)? skb->len : cov, 0); 163} 164 165extern void dccp_v4_send_check(struct sock *sk, int len, struct sk_buff *skb); 166 167extern int dccp_retransmit_skb(struct sock *sk, struct sk_buff *skb); 168 169extern void dccp_send_ack(struct sock *sk); 170extern void dccp_send_delayed_ack(struct sock *sk); 171extern void dccp_reqsk_send_ack(struct sk_buff *sk, struct request_sock *rsk); 172 173extern void dccp_send_sync(struct sock *sk, const u64 seq, 174 const enum dccp_pkt_type pkt_type); 175 176extern void dccp_write_xmit(struct sock *sk, int block); 177extern void dccp_write_space(struct sock *sk); 178 179extern void dccp_init_xmit_timers(struct sock *sk); 180static inline void dccp_clear_xmit_timers(struct sock *sk) 181{ 182 inet_csk_clear_xmit_timers(sk); 183} 184 185extern unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu); 186 187extern const char *dccp_packet_name(const int type); 188extern const char *dccp_state_name(const int state); 189 190extern void dccp_set_state(struct sock *sk, const int state); 191extern void dccp_done(struct sock *sk); 192 193extern void dccp_reqsk_init(struct request_sock *req, struct sk_buff *skb); 194 195extern int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb); 196 197extern struct sock *dccp_create_openreq_child(struct sock *sk, 198 const struct request_sock *req, 199 const struct sk_buff *skb); 200 201extern int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb); 202 203extern struct sock *dccp_v4_request_recv_sock(struct sock *sk, 204 struct sk_buff *skb, 205 struct request_sock *req, 206 struct dst_entry *dst); 207extern struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb, 208 struct request_sock *req, 209 struct request_sock **prev); 210 211extern int dccp_child_process(struct sock *parent, struct sock *child, 212 struct sk_buff *skb); 213extern int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, 214 struct dccp_hdr *dh, unsigned len); 215extern int dccp_rcv_established(struct sock *sk, struct sk_buff *skb, 216 const struct dccp_hdr *dh, const unsigned len); 217 218extern int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized); 219extern int dccp_destroy_sock(struct sock *sk); 220 221extern void dccp_close(struct sock *sk, long timeout); 222extern struct sk_buff *dccp_make_response(struct sock *sk, 223 struct dst_entry *dst, 224 struct request_sock *req); 225 226extern int dccp_connect(struct sock *sk); 227extern int dccp_disconnect(struct sock *sk, int flags); 228extern void dccp_hash(struct sock *sk); 229extern void dccp_unhash(struct sock *sk); 230extern int dccp_getsockopt(struct sock *sk, int level, int optname, 231 char __user *optval, int __user *optlen); 232extern int dccp_setsockopt(struct sock *sk, int level, int optname, 233 char __user *optval, int optlen); 234#ifdef CONFIG_COMPAT 235extern int compat_dccp_getsockopt(struct sock *sk, 236 int level, int optname, 237 char __user *optval, int __user *optlen); 238extern int compat_dccp_setsockopt(struct sock *sk, 239 int level, int optname, 240 char __user *optval, int optlen); 241#endif 242extern int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg); 243extern int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, 244 struct msghdr *msg, size_t size); 245extern int dccp_recvmsg(struct kiocb *iocb, struct sock *sk, 246 struct msghdr *msg, size_t len, int nonblock, 247 int flags, int *addr_len); 248extern void dccp_shutdown(struct sock *sk, int how); 249extern int inet_dccp_listen(struct socket *sock, int backlog); 250extern unsigned int dccp_poll(struct file *file, struct socket *sock, 251 poll_table *wait); 252extern int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, 253 int addr_len); 254 255extern int dccp_send_reset(struct sock *sk, enum dccp_reset_codes code); 256extern void dccp_send_close(struct sock *sk, const int active); 257extern int dccp_invalid_packet(struct sk_buff *skb); 258 259static inline int dccp_bad_service_code(const struct sock *sk, 260 const __be32 service) 261{ 262 const struct dccp_sock *dp = dccp_sk(sk); 263 264 if (dp->dccps_service == service) 265 return 0; 266 return !dccp_list_has_service(dp->dccps_service_list, service); 267} 268 269struct dccp_skb_cb { 270 __u8 dccpd_type:4; 271 __u8 dccpd_ccval:4; 272 __u8 dccpd_reset_code; 273 __u16 dccpd_opt_len; 274 __u64 dccpd_seq; 275 __u64 dccpd_ack_seq; 276}; 277 278#define DCCP_SKB_CB(__skb) ((struct dccp_skb_cb *)&((__skb)->cb[0])) 279 280static inline int dccp_non_data_packet(const struct sk_buff *skb) 281{ 282 const __u8 type = DCCP_SKB_CB(skb)->dccpd_type; 283 284 return type == DCCP_PKT_ACK || 285 type == DCCP_PKT_CLOSE || 286 type == DCCP_PKT_CLOSEREQ || 287 type == DCCP_PKT_RESET || 288 type == DCCP_PKT_SYNC || 289 type == DCCP_PKT_SYNCACK; 290} 291 292static inline int dccp_packet_without_ack(const struct sk_buff *skb) 293{ 294 const __u8 type = DCCP_SKB_CB(skb)->dccpd_type; 295 296 return type == DCCP_PKT_DATA || type == DCCP_PKT_REQUEST; 297} 298 299#define DCCP_MAX_SEQNO ((((u64)1) << 48) - 1) 300#define DCCP_PKT_WITHOUT_ACK_SEQ (DCCP_MAX_SEQNO << 2) 301 302static inline void dccp_set_seqno(u64 *seqno, u64 value) 303{ 304 if (value > DCCP_MAX_SEQNO) 305 value -= DCCP_MAX_SEQNO + 1; 306 *seqno = value; 307} 308 309static inline u64 dccp_delta_seqno(u64 seqno1, u64 seqno2) 310{ 311 return ((seqno2 << 16) - (seqno1 << 16)) >> 16; 312} 313 314static inline void dccp_inc_seqno(u64 *seqno) 315{ 316 if (++*seqno > DCCP_MAX_SEQNO) 317 *seqno = 0; 318} 319 320static inline void dccp_hdr_set_seq(struct dccp_hdr *dh, const u64 gss) 321{ 322 struct dccp_hdr_ext *dhx = (struct dccp_hdr_ext *)((void *)dh + 323 sizeof(*dh)); 324 dh->dccph_seq2 = 0; 325 dh->dccph_seq = htons((gss >> 32) & 0xfffff); 326 dhx->dccph_seq_low = htonl(gss & 0xffffffff); 327} 328 329static inline void dccp_hdr_set_ack(struct dccp_hdr_ack_bits *dhack, 330 const u64 gsr) 331{ 332 dhack->dccph_reserved1 = 0; 333 dhack->dccph_ack_nr_high = htons(gsr >> 32); 334 dhack->dccph_ack_nr_low = htonl(gsr & 0xffffffff); 335} 336 337static inline void dccp_update_gsr(struct sock *sk, u64 seq) 338{ 339 struct dccp_sock *dp = dccp_sk(sk); 340 const struct dccp_minisock *dmsk = dccp_msk(sk); 341 342 dp->dccps_gsr = seq; 343 dccp_set_seqno(&dp->dccps_swl, 344 dp->dccps_gsr + 1 - (dmsk->dccpms_sequence_window / 4)); 345 dccp_set_seqno(&dp->dccps_swh, 346 dp->dccps_gsr + (3 * dmsk->dccpms_sequence_window) / 4); 347} 348 349static inline void dccp_update_gss(struct sock *sk, u64 seq) 350{ 351 struct dccp_sock *dp = dccp_sk(sk); 352 353 dp->dccps_awh = dp->dccps_gss = seq; 354 dccp_set_seqno(&dp->dccps_awl, 355 (dp->dccps_gss - 356 dccp_msk(sk)->dccpms_sequence_window + 1)); 357} 358 359static inline int dccp_ack_pending(const struct sock *sk) 360{ 361 const struct dccp_sock *dp = dccp_sk(sk); 362 return dp->dccps_timestamp_echo != 0 || 363#ifdef CONFIG_IP_DCCP_ACKVEC 364 (dccp_msk(sk)->dccpms_send_ack_vector && 365 dccp_ackvec_pending(dp->dccps_hc_rx_ackvec)) || 366#endif 367 inet_csk_ack_scheduled(sk); 368} 369 370extern int dccp_insert_options(struct sock *sk, struct sk_buff *skb); 371extern int dccp_insert_option_elapsed_time(struct sock *sk, 372 struct sk_buff *skb, 373 u32 elapsed_time); 374extern int dccp_insert_option_timestamp(struct sock *sk, 375 struct sk_buff *skb); 376extern int dccp_insert_option(struct sock *sk, struct sk_buff *skb, 377 unsigned char option, 378 const void *value, unsigned char len); 379 380extern void dccp_timestamp(const struct sock *sk, struct timeval *tv); 381 382static inline suseconds_t timeval_usecs(const struct timeval *tv) 383{ 384 return tv->tv_sec * USEC_PER_SEC + tv->tv_usec; 385} 386 387static inline suseconds_t timeval_delta(const struct timeval *large, 388 const struct timeval *small) 389{ 390 time_t secs = large->tv_sec - small->tv_sec; 391 suseconds_t usecs = large->tv_usec - small->tv_usec; 392 393 if (usecs < 0) { 394 secs--; 395 usecs += USEC_PER_SEC; 396 } 397 return secs * USEC_PER_SEC + usecs; 398} 399 400static inline void timeval_add_usecs(struct timeval *tv, 401 const suseconds_t usecs) 402{ 403 tv->tv_usec += usecs; 404 while (tv->tv_usec >= USEC_PER_SEC) { 405 tv->tv_sec++; 406 tv->tv_usec -= USEC_PER_SEC; 407 } 408} 409 410static inline void timeval_sub_usecs(struct timeval *tv, 411 const suseconds_t usecs) 412{ 413 tv->tv_usec -= usecs; 414 while (tv->tv_usec < 0) { 415 tv->tv_sec--; 416 tv->tv_usec += USEC_PER_SEC; 417 } 418} 419 420#ifdef CONFIG_SYSCTL 421extern int dccp_sysctl_init(void); 422extern void dccp_sysctl_exit(void); 423#else 424static inline int dccp_sysctl_init(void) 425{ 426 return 0; 427} 428 429static inline void dccp_sysctl_exit(void) 430{ 431} 432#endif 433 434#endif /* _DCCP_H */ 435