| #ifndef _DCCP_H |
| #define _DCCP_H |
| /* |
| * net/dccp/dccp.h |
| * |
| * An implementation of the DCCP protocol |
| * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br> |
| * Copyright (c) 2005-6 Ian McDonald <ian.mcdonald@jandi.co.nz> |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| */ |
| |
| #include <linux/dccp.h> |
| #include <linux/ktime.h> |
| #include <net/snmp.h> |
| #include <net/sock.h> |
| #include <net/tcp.h> |
| #include "ackvec.h" |
| |
| /* |
| * DCCP - specific warning and debugging macros. |
| */ |
| #define DCCP_WARN(fmt, a...) LIMIT_NETDEBUG(KERN_WARNING "%s: " fmt, \ |
| __func__, ##a) |
| #define DCCP_CRIT(fmt, a...) printk(KERN_CRIT fmt " at %s:%d/%s()\n", ##a, \ |
| __FILE__, __LINE__, __func__) |
| #define DCCP_BUG(a...) do { DCCP_CRIT("BUG: " a); dump_stack(); } while(0) |
| #define DCCP_BUG_ON(cond) do { if (unlikely((cond) != 0)) \ |
| DCCP_BUG("\"%s\" holds (exception!)", \ |
| __stringify(cond)); \ |
| } while (0) |
| |
| #define DCCP_PRINTK(enable, fmt, args...) do { if (enable) \ |
| printk(fmt, ##args); \ |
| } while(0) |
| #define DCCP_PR_DEBUG(enable, fmt, a...) DCCP_PRINTK(enable, KERN_DEBUG \ |
| "%s: " fmt, __func__, ##a) |
| |
| #ifdef CONFIG_IP_DCCP_DEBUG |
| extern int dccp_debug; |
| #define dccp_pr_debug(format, a...) DCCP_PR_DEBUG(dccp_debug, format, ##a) |
| #define dccp_pr_debug_cat(format, a...) DCCP_PRINTK(dccp_debug, format, ##a) |
| #else |
| #define dccp_pr_debug(format, a...) |
| #define dccp_pr_debug_cat(format, a...) |
| #endif |
| |
| extern struct inet_hashinfo dccp_hashinfo; |
| |
| extern atomic_t dccp_orphan_count; |
| |
| extern void dccp_time_wait(struct sock *sk, int state, int timeo); |
| |
| /* |
| * Set safe upper bounds for header and option length. Since Data Offset is 8 |
| * bits (RFC 4340, sec. 5.1), the total header length can never be more than |
| * 4 * 255 = 1020 bytes. The largest possible header length is 28 bytes (X=1): |
| * - DCCP-Response with ACK Subheader and 4 bytes of Service code OR |
| * - DCCP-Reset with ACK Subheader and 4 bytes of Reset Code fields |
| * Hence a safe upper bound for the maximum option length is 1020-28 = 992 |
| */ |
| #define MAX_DCCP_SPECIFIC_HEADER (255 * sizeof(int)) |
| #define DCCP_MAX_PACKET_HDR 28 |
| #define DCCP_MAX_OPT_LEN (MAX_DCCP_SPECIFIC_HEADER - DCCP_MAX_PACKET_HDR) |
| #define MAX_DCCP_HEADER (MAX_DCCP_SPECIFIC_HEADER + MAX_HEADER) |
| |
| #define DCCP_TIMEWAIT_LEN (60 * HZ) /* how long to wait to destroy TIME-WAIT |
| * state, about 60 seconds */ |
| |
| /* RFC 1122, 4.2.3.1 initial RTO value */ |
| #define DCCP_TIMEOUT_INIT ((unsigned)(3 * HZ)) |
| |
| /* |
| * The maximum back-off value for retransmissions. This is needed for |
| * - retransmitting client-Requests (sec. 8.1.1), |
| * - retransmitting Close/CloseReq when closing (sec. 8.3), |
| * - feature-negotiation retransmission (sec. 6.6.3), |
| * - Acks in client-PARTOPEN state (sec. 8.1.5). |
| */ |
| #define DCCP_RTO_MAX ((unsigned)(64 * HZ)) |
| |
| /* |
| * RTT sampling: sanity bounds and fallback RTT value from RFC 4340, section 3.4 |
| */ |
| #define DCCP_SANE_RTT_MIN 100 |
| #define DCCP_FALLBACK_RTT (USEC_PER_SEC / 5) |
| #define DCCP_SANE_RTT_MAX (3 * USEC_PER_SEC) |
| |
| /* Maximal interval between probes for local resources. */ |
| #define DCCP_RESOURCE_PROBE_INTERVAL ((unsigned)(HZ / 2U)) |
| |
| /* sysctl variables for DCCP */ |
| extern int sysctl_dccp_request_retries; |
| extern int sysctl_dccp_retries1; |
| extern int sysctl_dccp_retries2; |
| extern int sysctl_dccp_feat_sequence_window; |
| extern int sysctl_dccp_feat_rx_ccid; |
| extern int sysctl_dccp_feat_tx_ccid; |
| extern int sysctl_dccp_feat_send_ack_vector; |
| extern int sysctl_dccp_tx_qlen; |
| extern int sysctl_dccp_sync_ratelimit; |
| |
| /* |
| * 48-bit sequence number arithmetic (signed and unsigned) |
| */ |
| #define INT48_MIN 0x800000000000LL /* 2^47 */ |
| #define UINT48_MAX 0xFFFFFFFFFFFFLL /* 2^48 - 1 */ |
| #define COMPLEMENT48(x) (0x1000000000000LL - (x)) /* 2^48 - x */ |
| #define TO_SIGNED48(x) (((x) < INT48_MIN)? (x) : -COMPLEMENT48( (x))) |
| #define TO_UNSIGNED48(x) (((x) >= 0)? (x) : COMPLEMENT48(-(x))) |
| #define ADD48(a, b) (((a) + (b)) & UINT48_MAX) |
| #define SUB48(a, b) ADD48((a), COMPLEMENT48(b)) |
| |
| static inline void dccp_set_seqno(u64 *seqno, u64 value) |
| { |
| *seqno = value & UINT48_MAX; |
| } |
| |
| static inline void dccp_inc_seqno(u64 *seqno) |
| { |
| *seqno = ADD48(*seqno, 1); |
| } |
| |
| /* signed mod-2^48 distance: pos. if seqno1 < seqno2, neg. if seqno1 > seqno2 */ |
| static inline s64 dccp_delta_seqno(const u64 seqno1, const u64 seqno2) |
| { |
| u64 delta = SUB48(seqno2, seqno1); |
| |
| return TO_SIGNED48(delta); |
| } |
| |
| /* is seq1 < seq2 ? */ |
| static inline int before48(const u64 seq1, const u64 seq2) |
| { |
| return (s64)((seq2 << 16) - (seq1 << 16)) > 0; |
| } |
| |
| /* is seq1 > seq2 ? */ |
| #define after48(seq1, seq2) before48(seq2, seq1) |
| |
| /* is seq2 <= seq1 <= seq3 ? */ |
| static inline int between48(const u64 seq1, const u64 seq2, const u64 seq3) |
| { |
| return (seq3 << 16) - (seq2 << 16) >= (seq1 << 16) - (seq2 << 16); |
| } |
| |
| static inline u64 max48(const u64 seq1, const u64 seq2) |
| { |
| return after48(seq1, seq2) ? seq1 : seq2; |
| } |
| |
| /** |
| * dccp_loss_free - Evaluates condition for data loss from RFC 4340, 7.7.1 |
| * @s1: start sequence number |
| * @s2: end sequence number |
| * @ndp: NDP count on packet with sequence number @s2 |
| * Returns true if the sequence range s1...s2 has no data loss. |
| */ |
| static inline bool dccp_loss_free(const u64 s1, const u64 s2, const u64 ndp) |
| { |
| s64 delta = dccp_delta_seqno(s1, s2); |
| |
| WARN_ON(delta < 0); |
| return (u64)delta <= ndp + 1; |
| } |
| |
| enum { |
| DCCP_MIB_NUM = 0, |
| DCCP_MIB_ACTIVEOPENS, /* ActiveOpens */ |
| DCCP_MIB_ESTABRESETS, /* EstabResets */ |
| DCCP_MIB_CURRESTAB, /* CurrEstab */ |
| DCCP_MIB_OUTSEGS, /* OutSegs */ |
| DCCP_MIB_OUTRSTS, |
| DCCP_MIB_ABORTONTIMEOUT, |
| DCCP_MIB_TIMEOUTS, |
| DCCP_MIB_ABORTFAILED, |
| DCCP_MIB_PASSIVEOPENS, |
| DCCP_MIB_ATTEMPTFAILS, |
| DCCP_MIB_OUTDATAGRAMS, |
| DCCP_MIB_INERRS, |
| DCCP_MIB_OPTMANDATORYERROR, |
| DCCP_MIB_INVALIDOPT, |
| __DCCP_MIB_MAX |
| }; |
| |
| #define DCCP_MIB_MAX __DCCP_MIB_MAX |
| struct dccp_mib { |
| unsigned long mibs[DCCP_MIB_MAX]; |
| } __SNMP_MIB_ALIGN__; |
| |
| DECLARE_SNMP_STAT(struct dccp_mib, dccp_statistics); |
| #define DCCP_INC_STATS(field) SNMP_INC_STATS(dccp_statistics, field) |
| #define DCCP_INC_STATS_BH(field) SNMP_INC_STATS_BH(dccp_statistics, field) |
| #define DCCP_INC_STATS_USER(field) SNMP_INC_STATS_USER(dccp_statistics, field) |
| #define DCCP_DEC_STATS(field) SNMP_DEC_STATS(dccp_statistics, field) |
| #define DCCP_ADD_STATS_BH(field, val) \ |
| SNMP_ADD_STATS_BH(dccp_statistics, field, val) |
| #define DCCP_ADD_STATS_USER(field, val) \ |
| SNMP_ADD_STATS_USER(dccp_statistics, field, val) |
| |
| /* |
| * Checksumming routines |
| */ |
| static inline unsigned int dccp_csum_coverage(const struct sk_buff *skb) |
| { |
| const struct dccp_hdr* dh = dccp_hdr(skb); |
| |
| if (dh->dccph_cscov == 0) |
| return skb->len; |
| return (dh->dccph_doff + dh->dccph_cscov - 1) * sizeof(u32); |
| } |
| |
| static inline void dccp_csum_outgoing(struct sk_buff *skb) |
| { |
| unsigned int cov = dccp_csum_coverage(skb); |
| |
| if (cov >= skb->len) |
| dccp_hdr(skb)->dccph_cscov = 0; |
| |
| skb->csum = skb_checksum(skb, 0, (cov > skb->len)? skb->len : cov, 0); |
| } |
| |
| extern void dccp_v4_send_check(struct sock *sk, int len, struct sk_buff *skb); |
| |
| extern int dccp_retransmit_skb(struct sock *sk); |
| |
| extern void dccp_send_ack(struct sock *sk); |
| extern void dccp_reqsk_send_ack(struct sock *sk, struct sk_buff *skb, |
| struct request_sock *rsk); |
| |
| extern void dccp_send_sync(struct sock *sk, const u64 seq, |
| const enum dccp_pkt_type pkt_type); |
| |
| extern void dccp_write_xmit(struct sock *sk, int block); |
| extern void dccp_write_space(struct sock *sk); |
| |
| extern void dccp_init_xmit_timers(struct sock *sk); |
| static inline void dccp_clear_xmit_timers(struct sock *sk) |
| { |
| inet_csk_clear_xmit_timers(sk); |
| } |
| |
| extern unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu); |
| |
| extern const char *dccp_packet_name(const int type); |
| extern const char *dccp_state_name(const int state); |
| |
| extern void dccp_set_state(struct sock *sk, const int state); |
| extern void dccp_done(struct sock *sk); |
| |
| extern int dccp_reqsk_init(struct request_sock *rq, struct dccp_sock const *dp, |
| struct sk_buff const *skb); |
| |
| extern int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb); |
| |
| extern struct sock *dccp_create_openreq_child(struct sock *sk, |
| const struct request_sock *req, |
| const struct sk_buff *skb); |
| |
| extern int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb); |
| |
| extern struct sock *dccp_v4_request_recv_sock(struct sock *sk, |
| struct sk_buff *skb, |
| struct request_sock *req, |
| struct dst_entry *dst); |
| extern struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb, |
| struct request_sock *req, |
| struct request_sock **prev); |
| |
| extern int dccp_child_process(struct sock *parent, struct sock *child, |
| struct sk_buff *skb); |
| extern int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb, |
| struct dccp_hdr *dh, unsigned len); |
| extern int dccp_rcv_established(struct sock *sk, struct sk_buff *skb, |
| const struct dccp_hdr *dh, const unsigned len); |
| |
| extern int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized); |
| extern void dccp_destroy_sock(struct sock *sk); |
| |
| extern void dccp_close(struct sock *sk, long timeout); |
| extern struct sk_buff *dccp_make_response(struct sock *sk, |
| struct dst_entry *dst, |
| struct request_sock *req); |
| |
| extern int dccp_connect(struct sock *sk); |
| extern int dccp_disconnect(struct sock *sk, int flags); |
| extern int dccp_getsockopt(struct sock *sk, int level, int optname, |
| char __user *optval, int __user *optlen); |
| extern int dccp_setsockopt(struct sock *sk, int level, int optname, |
| char __user *optval, int optlen); |
| #ifdef CONFIG_COMPAT |
| extern int compat_dccp_getsockopt(struct sock *sk, |
| int level, int optname, |
| char __user *optval, int __user *optlen); |
| extern int compat_dccp_setsockopt(struct sock *sk, |
| int level, int optname, |
| char __user *optval, int optlen); |
| #endif |
| extern int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg); |
| extern int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, |
| struct msghdr *msg, size_t size); |
| extern int dccp_recvmsg(struct kiocb *iocb, struct sock *sk, |
| struct msghdr *msg, size_t len, int nonblock, |
| int flags, int *addr_len); |
| extern void dccp_shutdown(struct sock *sk, int how); |
| extern int inet_dccp_listen(struct socket *sock, int backlog); |
| extern unsigned int dccp_poll(struct file *file, struct socket *sock, |
| poll_table *wait); |
| extern int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, |
| int addr_len); |
| |
| extern struct sk_buff *dccp_ctl_make_reset(struct sock *sk, |
| struct sk_buff *skb); |
| extern int dccp_send_reset(struct sock *sk, enum dccp_reset_codes code); |
| extern void dccp_send_close(struct sock *sk, const int active); |
| extern int dccp_invalid_packet(struct sk_buff *skb); |
| extern u32 dccp_sample_rtt(struct sock *sk, long delta); |
| |
| static inline int dccp_bad_service_code(const struct sock *sk, |
| const __be32 service) |
| { |
| const struct dccp_sock *dp = dccp_sk(sk); |
| |
| if (dp->dccps_service == service) |
| return 0; |
| return !dccp_list_has_service(dp->dccps_service_list, service); |
| } |
| |
| /** |
| * dccp_skb_cb - DCCP per-packet control information |
| * @dccpd_type: one of %dccp_pkt_type (or unknown) |
| * @dccpd_ccval: CCVal field (5.1), see e.g. RFC 4342, 8.1 |
| * @dccpd_reset_code: one of %dccp_reset_codes |
| * @dccpd_reset_data: Data1..3 fields (depend on @dccpd_reset_code) |
| * @dccpd_opt_len: total length of all options (5.8) in the packet |
| * @dccpd_seq: sequence number |
| * @dccpd_ack_seq: acknowledgment number subheader field value |
| * This is used for transmission as well as for reception. |
| */ |
| struct dccp_skb_cb { |
| union { |
| struct inet_skb_parm h4; |
| #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE) |
| struct inet6_skb_parm h6; |
| #endif |
| } header; |
| __u8 dccpd_type:4; |
| __u8 dccpd_ccval:4; |
| __u8 dccpd_reset_code, |
| dccpd_reset_data[3]; |
| __u16 dccpd_opt_len; |
| __u64 dccpd_seq; |
| __u64 dccpd_ack_seq; |
| }; |
| |
| #define DCCP_SKB_CB(__skb) ((struct dccp_skb_cb *)&((__skb)->cb[0])) |
| |
| /* RFC 4340, sec. 7.7 */ |
| static inline int dccp_non_data_packet(const struct sk_buff *skb) |
| { |
| const __u8 type = DCCP_SKB_CB(skb)->dccpd_type; |
| |
| return type == DCCP_PKT_ACK || |
| type == DCCP_PKT_CLOSE || |
| type == DCCP_PKT_CLOSEREQ || |
| type == DCCP_PKT_RESET || |
| type == DCCP_PKT_SYNC || |
| type == DCCP_PKT_SYNCACK; |
| } |
| |
| /* RFC 4340, sec. 7.7 */ |
| static inline int dccp_data_packet(const struct sk_buff *skb) |
| { |
| const __u8 type = DCCP_SKB_CB(skb)->dccpd_type; |
| |
| return type == DCCP_PKT_DATA || |
| type == DCCP_PKT_DATAACK || |
| type == DCCP_PKT_REQUEST || |
| type == DCCP_PKT_RESPONSE; |
| } |
| |
| static inline int dccp_packet_without_ack(const struct sk_buff *skb) |
| { |
| const __u8 type = DCCP_SKB_CB(skb)->dccpd_type; |
| |
| return type == DCCP_PKT_DATA || type == DCCP_PKT_REQUEST; |
| } |
| |
| #define DCCP_PKT_WITHOUT_ACK_SEQ (UINT48_MAX << 2) |
| |
| static inline void dccp_hdr_set_seq(struct dccp_hdr *dh, const u64 gss) |
| { |
| struct dccp_hdr_ext *dhx = (struct dccp_hdr_ext *)((void *)dh + |
| sizeof(*dh)); |
| dh->dccph_seq2 = 0; |
| dh->dccph_seq = htons((gss >> 32) & 0xfffff); |
| dhx->dccph_seq_low = htonl(gss & 0xffffffff); |
| } |
| |
| static inline void dccp_hdr_set_ack(struct dccp_hdr_ack_bits *dhack, |
| const u64 gsr) |
| { |
| dhack->dccph_reserved1 = 0; |
| dhack->dccph_ack_nr_high = htons(gsr >> 32); |
| dhack->dccph_ack_nr_low = htonl(gsr & 0xffffffff); |
| } |
| |
| static inline void dccp_update_gsr(struct sock *sk, u64 seq) |
| { |
| struct dccp_sock *dp = dccp_sk(sk); |
| const struct dccp_minisock *dmsk = dccp_msk(sk); |
| |
| dp->dccps_gsr = seq; |
| dccp_set_seqno(&dp->dccps_swl, |
| dp->dccps_gsr + 1 - (dmsk->dccpms_sequence_window / 4)); |
| dccp_set_seqno(&dp->dccps_swh, |
| dp->dccps_gsr + (3 * dmsk->dccpms_sequence_window) / 4); |
| } |
| |
| static inline void dccp_update_gss(struct sock *sk, u64 seq) |
| { |
| struct dccp_sock *dp = dccp_sk(sk); |
| |
| dp->dccps_awh = dp->dccps_gss = seq; |
| dccp_set_seqno(&dp->dccps_awl, |
| (dp->dccps_gss - |
| dccp_msk(sk)->dccpms_sequence_window + 1)); |
| } |
| |
| static inline int dccp_ack_pending(const struct sock *sk) |
| { |
| const struct dccp_sock *dp = dccp_sk(sk); |
| return dp->dccps_timestamp_echo != 0 || |
| #ifdef CONFIG_IP_DCCP_ACKVEC |
| (dccp_msk(sk)->dccpms_send_ack_vector && |
| dccp_ackvec_pending(dp->dccps_hc_rx_ackvec)) || |
| #endif |
| inet_csk_ack_scheduled(sk); |
| } |
| |
| extern int dccp_feat_finalise_settings(struct dccp_sock *dp); |
| extern int dccp_feat_server_ccid_dependencies(struct dccp_request_sock *dreq); |
| extern int dccp_feat_insert_opts(struct dccp_sock*, struct dccp_request_sock*, |
| struct sk_buff *skb); |
| extern int dccp_feat_activate_values(struct sock *sk, struct list_head *fn); |
| extern void dccp_feat_list_purge(struct list_head *fn_list); |
| |
| extern int dccp_insert_options(struct sock *sk, struct sk_buff *skb); |
| extern int dccp_insert_options_rsk(struct dccp_request_sock*, struct sk_buff*); |
| extern int dccp_insert_option_elapsed_time(struct sock *sk, |
| struct sk_buff *skb, |
| u32 elapsed_time); |
| extern u32 dccp_timestamp(void); |
| extern void dccp_timestamping_init(void); |
| extern int dccp_insert_option_timestamp(struct sock *sk, |
| struct sk_buff *skb); |
| extern int dccp_insert_option(struct sock *sk, struct sk_buff *skb, |
| unsigned char option, |
| const void *value, unsigned char len); |
| |
| #ifdef CONFIG_SYSCTL |
| extern int dccp_sysctl_init(void); |
| extern void dccp_sysctl_exit(void); |
| #else |
| static inline int dccp_sysctl_init(void) |
| { |
| return 0; |
| } |
| |
| static inline void dccp_sysctl_exit(void) |
| { |
| } |
| #endif |
| |
| #endif /* _DCCP_H */ |