| 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 <linux/ktime.h> |
| 17 | #include <net/snmp.h> |
| 18 | #include <net/sock.h> |
| 19 | #include <net/tcp.h> |
| 20 | #include "ackvec.h" |
| 21 | |
| 22 | /* |
| 23 | * DCCP - specific warning and debugging macros. |
| 24 | */ |
| 25 | #define DCCP_WARN(fmt, a...) LIMIT_NETDEBUG(KERN_WARNING "%s: " fmt, \ |
| 26 | __FUNCTION__, ##a) |
| 27 | #define DCCP_CRIT(fmt, a...) printk(KERN_CRIT fmt " at %s:%d/%s()\n", ##a, \ |
| 28 | __FILE__, __LINE__, __FUNCTION__) |
| 29 | #define DCCP_BUG(a...) do { DCCP_CRIT("BUG: " a); dump_stack(); } while(0) |
| 30 | #define DCCP_BUG_ON(cond) do { if (unlikely((cond) != 0)) \ |
| 31 | DCCP_BUG("\"%s\" holds (exception!)", \ |
| 32 | __stringify(cond)); \ |
| 33 | } while (0) |
| 34 | |
| 35 | #define DCCP_PRINTK(enable, fmt, args...) do { if (enable) \ |
| 36 | printk(fmt, ##args); \ |
| 37 | } while(0) |
| 38 | #define DCCP_PR_DEBUG(enable, fmt, a...) DCCP_PRINTK(enable, KERN_DEBUG \ |
| 39 | "%s: " fmt, __FUNCTION__, ##a) |
| 40 | |
| 41 | #ifdef CONFIG_IP_DCCP_DEBUG |
| 42 | extern int dccp_debug; |
| 43 | #define dccp_pr_debug(format, a...) DCCP_PR_DEBUG(dccp_debug, format, ##a) |
| 44 | #define dccp_pr_debug_cat(format, a...) DCCP_PRINTK(dccp_debug, format, ##a) |
| 45 | #else |
| 46 | #define dccp_pr_debug(format, a...) |
| 47 | #define dccp_pr_debug_cat(format, a...) |
| 48 | #endif |
| 49 | |
| 50 | extern struct inet_hashinfo dccp_hashinfo; |
| 51 | |
| 52 | extern atomic_t dccp_orphan_count; |
| 53 | |
| 54 | extern void dccp_time_wait(struct sock *sk, int state, int timeo); |
| 55 | |
| 56 | /* |
| 57 | * Set safe upper bounds for header and option length. Since Data Offset is 8 |
| 58 | * bits (RFC 4340, sec. 5.1), the total header length can never be more than |
| 59 | * 4 * 255 = 1020 bytes. The largest possible header length is 28 bytes (X=1): |
| 60 | * - DCCP-Response with ACK Subheader and 4 bytes of Service code OR |
| 61 | * - DCCP-Reset with ACK Subheader and 4 bytes of Reset Code fields |
| 62 | * Hence a safe upper bound for the maximum option length is 1020-28 = 992 |
| 63 | */ |
| 64 | #define MAX_DCCP_SPECIFIC_HEADER (255 * sizeof(int)) |
| 65 | #define DCCP_MAX_PACKET_HDR 28 |
| 66 | #define DCCP_MAX_OPT_LEN (MAX_DCCP_SPECIFIC_HEADER - DCCP_MAX_PACKET_HDR) |
| 67 | #define MAX_DCCP_HEADER (MAX_DCCP_SPECIFIC_HEADER + MAX_HEADER) |
| 68 | |
| 69 | #define DCCP_TIMEWAIT_LEN (60 * HZ) /* how long to wait to destroy TIME-WAIT |
| 70 | * state, about 60 seconds */ |
| 71 | |
| 72 | /* RFC 1122, 4.2.3.1 initial RTO value */ |
| 73 | #define DCCP_TIMEOUT_INIT ((unsigned)(3 * HZ)) |
| 74 | |
| 75 | /* |
| 76 | * The maximum back-off value for retransmissions. This is needed for |
| 77 | * - retransmitting client-Requests (sec. 8.1.1), |
| 78 | * - retransmitting Close/CloseReq when closing (sec. 8.3), |
| 79 | * - feature-negotiation retransmission (sec. 6.6.3), |
| 80 | * - Acks in client-PARTOPEN state (sec. 8.1.5). |
| 81 | */ |
| 82 | #define DCCP_RTO_MAX ((unsigned)(64 * HZ)) |
| 83 | |
| 84 | /* |
| 85 | * RTT sampling: sanity bounds and fallback RTT value from RFC 4340, section 3.4 |
| 86 | */ |
| 87 | #define DCCP_SANE_RTT_MIN 100 |
| 88 | #define DCCP_FALLBACK_RTT (USEC_PER_SEC / 5) |
| 89 | #define DCCP_SANE_RTT_MAX (3 * USEC_PER_SEC) |
| 90 | |
| 91 | /* Maximal interval between probes for local resources. */ |
| 92 | #define DCCP_RESOURCE_PROBE_INTERVAL ((unsigned)(HZ / 2U)) |
| 93 | |
| 94 | /* sysctl variables for DCCP */ |
| 95 | extern int sysctl_dccp_request_retries; |
| 96 | extern int sysctl_dccp_retries1; |
| 97 | extern int sysctl_dccp_retries2; |
| 98 | extern int sysctl_dccp_feat_sequence_window; |
| 99 | extern int sysctl_dccp_feat_rx_ccid; |
| 100 | extern int sysctl_dccp_feat_tx_ccid; |
| 101 | extern int sysctl_dccp_feat_ack_ratio; |
| 102 | extern int sysctl_dccp_feat_send_ack_vector; |
| 103 | extern int sysctl_dccp_feat_send_ndp_count; |
| 104 | extern int sysctl_dccp_tx_qlen; |
| 105 | extern int sysctl_dccp_sync_ratelimit; |
| 106 | |
| 107 | /* |
| 108 | * 48-bit sequence number arithmetic (signed and unsigned) |
| 109 | */ |
| 110 | #define INT48_MIN 0x800000000000LL /* 2^47 */ |
| 111 | #define UINT48_MAX 0xFFFFFFFFFFFFLL /* 2^48 - 1 */ |
| 112 | #define COMPLEMENT48(x) (0x1000000000000LL - (x)) /* 2^48 - x */ |
| 113 | #define TO_SIGNED48(x) (((x) < INT48_MIN)? (x) : -COMPLEMENT48( (x))) |
| 114 | #define TO_UNSIGNED48(x) (((x) >= 0)? (x) : COMPLEMENT48(-(x))) |
| 115 | #define ADD48(a, b) (((a) + (b)) & UINT48_MAX) |
| 116 | #define SUB48(a, b) ADD48((a), COMPLEMENT48(b)) |
| 117 | |
| 118 | static inline void dccp_set_seqno(u64 *seqno, u64 value) |
| 119 | { |
| 120 | *seqno = value & UINT48_MAX; |
| 121 | } |
| 122 | |
| 123 | static inline void dccp_inc_seqno(u64 *seqno) |
| 124 | { |
| 125 | *seqno = ADD48(*seqno, 1); |
| 126 | } |
| 127 | |
| 128 | /* signed mod-2^48 distance: pos. if seqno1 < seqno2, neg. if seqno1 > seqno2 */ |
| 129 | static inline s64 dccp_delta_seqno(const u64 seqno1, const u64 seqno2) |
| 130 | { |
| 131 | u64 delta = SUB48(seqno2, seqno1); |
| 132 | |
| 133 | return TO_SIGNED48(delta); |
| 134 | } |
| 135 | |
| 136 | /* is seq1 < seq2 ? */ |
| 137 | static inline int before48(const u64 seq1, const u64 seq2) |
| 138 | { |
| 139 | return (s64)((seq2 << 16) - (seq1 << 16)) > 0; |
| 140 | } |
| 141 | |
| 142 | /* is seq1 > seq2 ? */ |
| 143 | #define after48(seq1, seq2) before48(seq2, seq1) |
| 144 | |
| 145 | /* is seq2 <= seq1 <= seq3 ? */ |
| 146 | static inline int between48(const u64 seq1, const u64 seq2, const u64 seq3) |
| 147 | { |
| 148 | return (seq3 << 16) - (seq2 << 16) >= (seq1 << 16) - (seq2 << 16); |
| 149 | } |
| 150 | |
| 151 | static inline u64 max48(const u64 seq1, const u64 seq2) |
| 152 | { |
| 153 | return after48(seq1, seq2) ? seq1 : seq2; |
| 154 | } |
| 155 | |
| 156 | enum { |
| 157 | DCCP_MIB_NUM = 0, |
| 158 | DCCP_MIB_ACTIVEOPENS, /* ActiveOpens */ |
| 159 | DCCP_MIB_ESTABRESETS, /* EstabResets */ |
| 160 | DCCP_MIB_CURRESTAB, /* CurrEstab */ |
| 161 | DCCP_MIB_OUTSEGS, /* OutSegs */ |
| 162 | DCCP_MIB_OUTRSTS, |
| 163 | DCCP_MIB_ABORTONTIMEOUT, |
| 164 | DCCP_MIB_TIMEOUTS, |
| 165 | DCCP_MIB_ABORTFAILED, |
| 166 | DCCP_MIB_PASSIVEOPENS, |
| 167 | DCCP_MIB_ATTEMPTFAILS, |
| 168 | DCCP_MIB_OUTDATAGRAMS, |
| 169 | DCCP_MIB_INERRS, |
| 170 | DCCP_MIB_OPTMANDATORYERROR, |
| 171 | DCCP_MIB_INVALIDOPT, |
| 172 | __DCCP_MIB_MAX |
| 173 | }; |
| 174 | |
| 175 | #define DCCP_MIB_MAX __DCCP_MIB_MAX |
| 176 | struct dccp_mib { |
| 177 | unsigned long mibs[DCCP_MIB_MAX]; |
| 178 | } __SNMP_MIB_ALIGN__; |
| 179 | |
| 180 | DECLARE_SNMP_STAT(struct dccp_mib, dccp_statistics); |
| 181 | #define DCCP_INC_STATS(field) SNMP_INC_STATS(dccp_statistics, field) |
| 182 | #define DCCP_INC_STATS_BH(field) SNMP_INC_STATS_BH(dccp_statistics, field) |
| 183 | #define DCCP_INC_STATS_USER(field) SNMP_INC_STATS_USER(dccp_statistics, field) |
| 184 | #define DCCP_DEC_STATS(field) SNMP_DEC_STATS(dccp_statistics, field) |
| 185 | #define DCCP_ADD_STATS_BH(field, val) \ |
| 186 | SNMP_ADD_STATS_BH(dccp_statistics, field, val) |
| 187 | #define DCCP_ADD_STATS_USER(field, val) \ |
| 188 | SNMP_ADD_STATS_USER(dccp_statistics, field, val) |
| 189 | |
| 190 | /* |
| 191 | * Checksumming routines |
| 192 | */ |
| 193 | static inline unsigned int dccp_csum_coverage(const struct sk_buff *skb) |
| 194 | { |
| 195 | const struct dccp_hdr* dh = dccp_hdr(skb); |
| 196 | |
| 197 | if (dh->dccph_cscov == 0) |
| 198 | return skb->len; |
| 199 | return (dh->dccph_doff + dh->dccph_cscov - 1) * sizeof(u32); |
| 200 | } |
| 201 | |
| 202 | static inline void dccp_csum_outgoing(struct sk_buff *skb) |
| 203 | { |
| 204 | unsigned int cov = dccp_csum_coverage(skb); |
| 205 | |
| 206 | if (cov >= skb->len) |
| 207 | dccp_hdr(skb)->dccph_cscov = 0; |
| 208 | |
| 209 | skb->csum = skb_checksum(skb, 0, (cov > skb->len)? skb->len : cov, 0); |
| 210 | } |
| 211 | |
| 212 | extern void dccp_v4_send_check(struct sock *sk, int len, struct sk_buff *skb); |
| 213 | |
| 214 | extern int dccp_retransmit_skb(struct sock *sk, struct sk_buff *skb); |
| 215 | |
| 216 | extern void dccp_send_ack(struct sock *sk); |
| 217 | extern void dccp_reqsk_send_ack(struct sk_buff *sk, struct request_sock *rsk); |
| 218 | |
| 219 | extern void dccp_send_sync(struct sock *sk, const u64 seq, |
| 220 | const enum dccp_pkt_type pkt_type); |
| 221 | |
| 222 | extern void dccp_write_xmit(struct sock *sk, int block); |
| 223 | extern void dccp_write_space(struct sock *sk); |
| 224 | |
| 225 | extern void dccp_init_xmit_timers(struct sock *sk); |
| 226 | static inline void dccp_clear_xmit_timers(struct sock *sk) |
| 227 | { |
| 228 | inet_csk_clear_xmit_timers(sk); |
| 229 | } |
| 230 | |
| 231 | extern unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu); |
| 232 | |
| 233 | extern const char *dccp_packet_name(const int type); |
| 234 | extern const char *dccp_state_name(const int state); |
| 235 | |
| 236 | extern void dccp_set_state(struct sock *sk, const int state); |
| 237 | extern void dccp_done(struct sock *sk); |
| 238 | |
| 239 | extern void dccp_reqsk_init(struct request_sock *req, struct sk_buff *skb); |
| 240 | |
| 241 | extern int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb); |
| 242 | |
| 243 | extern struct sock *dccp_create_openreq_child(struct sock *sk, |
| 244 | const struct request_sock *req, |
| 245 | const struct sk_buff *skb); |
| 246 | |
| 247 | extern int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb); |
| 248 | |
| 249 | extern struct sock *dccp_v4_request_recv_sock(struct sock *sk, |
| 250 | struct sk_buff *skb, |
| 251 | struct request_sock *req, |
| 252 | struct dst_entry *dst); |
| 253 | extern struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb, |
| 254 | struct request_sock *req, |
| 255 | struct request_sock **prev); |
| 256 | |
| 257 | extern int dccp_child_process(struct sock *parent, struct sock *child, |
| 258 | struct sk_buff *skb); |
| 259 | extern int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, |
| 260 | struct dccp_hdr *dh, unsigned len); |
| 261 | extern int dccp_rcv_established(struct sock *sk, struct sk_buff *skb, |
| 262 | const struct dccp_hdr *dh, const unsigned len); |
| 263 | |
| 264 | extern int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized); |
| 265 | extern int dccp_destroy_sock(struct sock *sk); |
| 266 | |
| 267 | extern void dccp_close(struct sock *sk, long timeout); |
| 268 | extern struct sk_buff *dccp_make_response(struct sock *sk, |
| 269 | struct dst_entry *dst, |
| 270 | struct request_sock *req); |
| 271 | |
| 272 | extern int dccp_connect(struct sock *sk); |
| 273 | extern int dccp_disconnect(struct sock *sk, int flags); |
| 274 | extern int dccp_getsockopt(struct sock *sk, int level, int optname, |
| 275 | char __user *optval, int __user *optlen); |
| 276 | extern int dccp_setsockopt(struct sock *sk, int level, int optname, |
| 277 | char __user *optval, int optlen); |
| 278 | #ifdef CONFIG_COMPAT |
| 279 | extern int compat_dccp_getsockopt(struct sock *sk, |
| 280 | int level, int optname, |
| 281 | char __user *optval, int __user *optlen); |
| 282 | extern int compat_dccp_setsockopt(struct sock *sk, |
| 283 | int level, int optname, |
| 284 | char __user *optval, int optlen); |
| 285 | #endif |
| 286 | extern int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg); |
| 287 | extern int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, |
| 288 | struct msghdr *msg, size_t size); |
| 289 | extern int dccp_recvmsg(struct kiocb *iocb, struct sock *sk, |
| 290 | struct msghdr *msg, size_t len, int nonblock, |
| 291 | int flags, int *addr_len); |
| 292 | extern void dccp_shutdown(struct sock *sk, int how); |
| 293 | extern int inet_dccp_listen(struct socket *sock, int backlog); |
| 294 | extern unsigned int dccp_poll(struct file *file, struct socket *sock, |
| 295 | poll_table *wait); |
| 296 | extern int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, |
| 297 | int addr_len); |
| 298 | |
| 299 | extern struct sk_buff *dccp_ctl_make_reset(struct socket *ctl, |
| 300 | struct sk_buff *skb); |
| 301 | extern int dccp_send_reset(struct sock *sk, enum dccp_reset_codes code); |
| 302 | extern void dccp_send_close(struct sock *sk, const int active); |
| 303 | extern int dccp_invalid_packet(struct sk_buff *skb); |
| 304 | extern u32 dccp_sample_rtt(struct sock *sk, long delta); |
| 305 | |
| 306 | static inline int dccp_bad_service_code(const struct sock *sk, |
| 307 | const __be32 service) |
| 308 | { |
| 309 | const struct dccp_sock *dp = dccp_sk(sk); |
| 310 | |
| 311 | if (dp->dccps_service == service) |
| 312 | return 0; |
| 313 | return !dccp_list_has_service(dp->dccps_service_list, service); |
| 314 | } |
| 315 | |
| 316 | /** |
| 317 | * dccp_skb_cb - DCCP per-packet control information |
| 318 | * @dccpd_type: one of %dccp_pkt_type (or unknown) |
| 319 | * @dccpd_ccval: CCVal field (5.1), see e.g. RFC 4342, 8.1 |
| 320 | * @dccpd_reset_code: one of %dccp_reset_codes |
| 321 | * @dccpd_reset_data: Data1..3 fields (depend on @dccpd_reset_code) |
| 322 | * @dccpd_opt_len: total length of all options (5.8) in the packet |
| 323 | * @dccpd_seq: sequence number |
| 324 | * @dccpd_ack_seq: acknowledgment number subheader field value |
| 325 | * This is used for transmission as well as for reception. |
| 326 | */ |
| 327 | struct dccp_skb_cb { |
| 328 | __u8 dccpd_type:4; |
| 329 | __u8 dccpd_ccval:4; |
| 330 | __u8 dccpd_reset_code, |
| 331 | dccpd_reset_data[3]; |
| 332 | __u16 dccpd_opt_len; |
| 333 | __u64 dccpd_seq; |
| 334 | __u64 dccpd_ack_seq; |
| 335 | }; |
| 336 | |
| 337 | #define DCCP_SKB_CB(__skb) ((struct dccp_skb_cb *)&((__skb)->cb[0])) |
| 338 | |
| 339 | /* RFC 4340, sec. 7.7 */ |
| 340 | static inline int dccp_non_data_packet(const struct sk_buff *skb) |
| 341 | { |
| 342 | const __u8 type = DCCP_SKB_CB(skb)->dccpd_type; |
| 343 | |
| 344 | return type == DCCP_PKT_ACK || |
| 345 | type == DCCP_PKT_CLOSE || |
| 346 | type == DCCP_PKT_CLOSEREQ || |
| 347 | type == DCCP_PKT_RESET || |
| 348 | type == DCCP_PKT_SYNC || |
| 349 | type == DCCP_PKT_SYNCACK; |
| 350 | } |
| 351 | |
| 352 | /* RFC 4340, sec. 7.7 */ |
| 353 | static inline int dccp_data_packet(const struct sk_buff *skb) |
| 354 | { |
| 355 | const __u8 type = DCCP_SKB_CB(skb)->dccpd_type; |
| 356 | |
| 357 | return type == DCCP_PKT_DATA || |
| 358 | type == DCCP_PKT_DATAACK || |
| 359 | type == DCCP_PKT_REQUEST || |
| 360 | type == DCCP_PKT_RESPONSE; |
| 361 | } |
| 362 | |
| 363 | static inline int dccp_packet_without_ack(const struct sk_buff *skb) |
| 364 | { |
| 365 | const __u8 type = DCCP_SKB_CB(skb)->dccpd_type; |
| 366 | |
| 367 | return type == DCCP_PKT_DATA || type == DCCP_PKT_REQUEST; |
| 368 | } |
| 369 | |
| 370 | #define DCCP_PKT_WITHOUT_ACK_SEQ (UINT48_MAX << 2) |
| 371 | |
| 372 | static inline void dccp_hdr_set_seq(struct dccp_hdr *dh, const u64 gss) |
| 373 | { |
| 374 | struct dccp_hdr_ext *dhx = (struct dccp_hdr_ext *)((void *)dh + |
| 375 | sizeof(*dh)); |
| 376 | dh->dccph_seq2 = 0; |
| 377 | dh->dccph_seq = htons((gss >> 32) & 0xfffff); |
| 378 | dhx->dccph_seq_low = htonl(gss & 0xffffffff); |
| 379 | } |
| 380 | |
| 381 | static inline void dccp_hdr_set_ack(struct dccp_hdr_ack_bits *dhack, |
| 382 | const u64 gsr) |
| 383 | { |
| 384 | dhack->dccph_reserved1 = 0; |
| 385 | dhack->dccph_ack_nr_high = htons(gsr >> 32); |
| 386 | dhack->dccph_ack_nr_low = htonl(gsr & 0xffffffff); |
| 387 | } |
| 388 | |
| 389 | static inline void dccp_update_gsr(struct sock *sk, u64 seq) |
| 390 | { |
| 391 | struct dccp_sock *dp = dccp_sk(sk); |
| 392 | const struct dccp_minisock *dmsk = dccp_msk(sk); |
| 393 | |
| 394 | dp->dccps_gsr = seq; |
| 395 | dccp_set_seqno(&dp->dccps_swl, |
| 396 | dp->dccps_gsr + 1 - (dmsk->dccpms_sequence_window / 4)); |
| 397 | dccp_set_seqno(&dp->dccps_swh, |
| 398 | dp->dccps_gsr + (3 * dmsk->dccpms_sequence_window) / 4); |
| 399 | } |
| 400 | |
| 401 | static inline void dccp_update_gss(struct sock *sk, u64 seq) |
| 402 | { |
| 403 | struct dccp_sock *dp = dccp_sk(sk); |
| 404 | |
| 405 | dp->dccps_awh = dp->dccps_gss = seq; |
| 406 | dccp_set_seqno(&dp->dccps_awl, |
| 407 | (dp->dccps_gss - |
| 408 | dccp_msk(sk)->dccpms_sequence_window + 1)); |
| 409 | } |
| 410 | |
| 411 | static inline int dccp_ack_pending(const struct sock *sk) |
| 412 | { |
| 413 | const struct dccp_sock *dp = dccp_sk(sk); |
| 414 | return dp->dccps_timestamp_echo != 0 || |
| 415 | #ifdef CONFIG_IP_DCCP_ACKVEC |
| 416 | (dccp_msk(sk)->dccpms_send_ack_vector && |
| 417 | dccp_ackvec_pending(dp->dccps_hc_rx_ackvec)) || |
| 418 | #endif |
| 419 | inet_csk_ack_scheduled(sk); |
| 420 | } |
| 421 | |
| 422 | extern int dccp_insert_options(struct sock *sk, struct sk_buff *skb); |
| 423 | extern int dccp_insert_options_rsk(struct dccp_request_sock*, struct sk_buff*); |
| 424 | extern int dccp_insert_option_elapsed_time(struct sock *sk, |
| 425 | struct sk_buff *skb, |
| 426 | u32 elapsed_time); |
| 427 | extern u32 dccp_timestamp(void); |
| 428 | extern void dccp_timestamping_init(void); |
| 429 | extern int dccp_insert_option_timestamp(struct sock *sk, |
| 430 | struct sk_buff *skb); |
| 431 | extern int dccp_insert_option(struct sock *sk, struct sk_buff *skb, |
| 432 | unsigned char option, |
| 433 | const void *value, unsigned char len); |
| 434 | |
| 435 | #ifdef CONFIG_SYSCTL |
| 436 | extern int dccp_sysctl_init(void); |
| 437 | extern void dccp_sysctl_exit(void); |
| 438 | #else |
| 439 | static inline int dccp_sysctl_init(void) |
| 440 | { |
| 441 | return 0; |
| 442 | } |
| 443 | |
| 444 | static inline void dccp_sysctl_exit(void) |
| 445 | { |
| 446 | } |
| 447 | #endif |
| 448 | |
| 449 | #endif /* _DCCP_H */ |