#ifndef _DCCP_H #define _DCCP_H /* * net/dccp/dccp.h * * An implementation of the DCCP protocol * Copyright (c) 2005 Arnaldo Carvalho de Melo * Copyright (c) 2005-6 Ian McDonald * * 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 #include #include #include #include "ackvec.h" /* * DCCP - specific warning and debugging macros. */ #define DCCP_WARN(fmt, a...) LIMIT_NETDEBUG(KERN_WARNING "%s: " fmt, \ __FUNCTION__, ##a) #define DCCP_CRIT(fmt, a...) printk(KERN_CRIT fmt " at %s:%d/%s()\n", ##a, \ __FILE__, __LINE__, __FUNCTION__) #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, __FUNCTION__, ##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)) #define DCCP_RTO_MAX ((unsigned)(120 * HZ)) /* FIXME: using TCP value */ /* bounds for sampled RTT values from packet exchanges (in usec) */ #define DCCP_SANE_RTT_MIN 100 #define DCCP_SANE_RTT_MAX (4 * 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_ack_ratio; extern int sysctl_dccp_feat_send_ack_vector; extern int sysctl_dccp_feat_send_ndp_count; extern int sysctl_dccp_tx_qlen; /* * 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; } /* is seq1 next seqno after seq2 */ static inline int follows48(const u64 seq1, const u64 seq2) { return dccp_delta_seqno(seq2, seq1) == 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, struct sk_buff *skb); extern void dccp_send_ack(struct sock *sk); extern void dccp_send_delayed_ack(struct sock *sk); extern void dccp_reqsk_send_ack(struct sk_buff *sk, 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 void dccp_reqsk_init(struct request_sock *req, struct sk_buff *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 int 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 void dccp_hash(struct sock *sk); extern void dccp_unhash(struct sock *sk); 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 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, struct timeval *t_recv, struct timeval *t_history); 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); } struct dccp_skb_cb { __u8 dccpd_type:4; __u8 dccpd_ccval:4; __u8 dccpd_reset_code; __u16 dccpd_opt_len; __u64 dccpd_seq; __u64 dccpd_ack_seq; }; #define DCCP_SKB_CB(__skb) ((struct dccp_skb_cb *)&((__skb)->cb[0])) 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; } 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_insert_options(struct sock *sk, struct sk_buff *skb); extern int dccp_insert_option_elapsed_time(struct sock *sk, struct sk_buff *skb, u32 elapsed_time); 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); extern void dccp_timestamp(const struct sock *sk, struct timeval *tv); static inline suseconds_t timeval_usecs(const struct timeval *tv) { return tv->tv_sec * USEC_PER_SEC + tv->tv_usec; } static inline suseconds_t timeval_delta(const struct timeval *large, const struct timeval *small) { time_t secs = large->tv_sec - small->tv_sec; suseconds_t usecs = large->tv_usec - small->tv_usec; if (usecs < 0) { secs--; usecs += USEC_PER_SEC; } return secs * USEC_PER_SEC + usecs; } static inline void timeval_add_usecs(struct timeval *tv, const suseconds_t usecs) { tv->tv_usec += usecs; while (tv->tv_usec >= USEC_PER_SEC) { tv->tv_sec++; tv->tv_usec -= USEC_PER_SEC; } } static inline void timeval_sub_usecs(struct timeval *tv, const suseconds_t usecs) { tv->tv_usec -= usecs; while (tv->tv_usec < 0) { tv->tv_sec--; tv->tv_usec += USEC_PER_SEC; } DCCP_BUG_ON(tv->tv_sec < 0); } #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 */