/* * Copyright (c) 2016 Cisco and/or its affiliates. * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #ifndef _vnet_tcp_h_ #define _vnet_tcp_h_ #include <vnet/vnet.h> #include <vnet/ip/ip.h> #include <vnet/tcp/tcp_packet.h> #include <vnet/tcp/tcp_timer.h> #include <vnet/session/transport.h> #include <vnet/session/session.h> #include <vnet/tcp/tcp_debug.h> #define TCP_TICK 0.001 /**< TCP tick period (s) */ #define THZ (u32) (1/TCP_TICK) /**< TCP tick frequency */ #define TCP_TSTAMP_RESOLUTION TCP_TICK /**< Time stamp resolution */ #define TCP_PAWS_IDLE 24 * 24 * 60 * 60 * THZ /**< 24 days */ #define TCP_MAX_OPTION_SPACE 40 #define TCP_DUPACK_THRESHOLD 3 #define TCP_MAX_RX_FIFO_SIZE 2 << 20 #define TCP_IW_N_SEGMENTS 10 #define TCP_ALWAYS_ACK 0 /**< If on, we always ack */ /** TCP FSM state definitions as per RFC793. */ #define foreach_tcp_fsm_state \ _(CLOSED, "CLOSED") \ _(LISTEN, "LISTEN") \ _(SYN_SENT, "SYN_SENT") \ _(SYN_RCVD, "SYN_RCVD") \ _(ESTABLISHED, "ESTABLISHED") \ _(CLOSE_WAIT, "CLOSE_WAIT") \ _(FIN_WAIT_1, "FIN_WAIT_1") \ _(LAST_ACK, "LAST_ACK") \ _(CLOSING, "CLOSING") \ _(FIN_WAIT_2, "FIN_WAIT_2") \ _(TIME_WAIT, "TIME_WAIT") typedef enum _tcp_state { #define _(sym, str) TCP_STATE_##sym, foreach_tcp_fsm_state #undef _ TCP_N_STATES } tcp_state_t; format_function_t format_tcp_state; format_function_t format_tcp_flags; format_function_t format_tcp_sacks; /** TCP timers */ #define foreach_tcp_timer \ _(RETRANSMIT, "RETRANSMIT") \ _(DELACK, "DELAYED ACK") \ _(PERSIST, "PERSIST") \ _(KEEP, "KEEP") \ _(WAITCLOSE, "WAIT CLOSE") \ _(RETRANSMIT_SYN, "RETRANSMIT SYN") \ _(ESTABLISH, "ESTABLISH") typedef enum _tcp_timers { #define _(sym, str) TCP_TIMER_##sym, foreach_tcp_timer #undef _ TCP_N_TIMERS } tcp_timers_e; typedef void (timer_expiration_handler) (u32 index); extern timer_expiration_handler tcp_timer_delack_handler; extern timer_expiration_handler tcp_timer_retransmit_handler; extern timer_expiration_handler tcp_timer_persist_handler; extern timer_expiration_handler tcp_timer_retransmit_syn_handler; #define TCP_TIMER_HANDLE_INVALID ((u32) ~0) /* Timer delays as multiples of 100ms */ #define TCP_TO_TIMER_TICK TCP_TICK*10 /* Period for converting from TCP * ticks to timer units */ #define TCP_DELACK_TIME 1 /* 0.1s */ #define TCP_ESTABLISH_TIME 750 /* 75s */ #define TCP_2MSL_TIME 300 /* 30s */ #define TCP_CLOSEWAIT_TIME 1 /* 0.1s */ #define TCP_CLEANUP_TIME 5 /* 0.5s Time to wait before cleanup */ #define TCP_TIMER_PERSIST_MIN 2 /* 0.2s */ #define TCP_RTO_MAX 60 * THZ /* Min max RTO (60s) as per RFC6298 */ #define TCP_RTT_MAX 30 * THZ /* 30s (probably too much) */ #define TCP_RTO_SYN_RETRIES 3 /* SYN retries without doubling RTO */ #define TCP_RTO_INIT 1 * THZ /* Initial retransmit timer */ /** TCP connection flags */ #define foreach_tcp_connection_flag \ _(SNDACK, "Send ACK") \ _(FINSNT, "FIN sent") \ _(SENT_RCV_WND0, "Sent 0 receive window") \ _(RECOVERY, "Recovery on") \ _(FAST_RECOVERY, "Fast Recovery on") \ _(FR_1_SMSS, "Sent 1 SMSS") typedef enum _tcp_connection_flag_bits { #define _(sym, str) TCP_CONN_##sym##_BIT, foreach_tcp_connection_flag #undef _ TCP_CONN_N_FLAG_BITS } tcp_connection_flag_bits_e; typedef enum _tcp_connection_flag { #define _(sym, str) TCP_CONN_##sym = 1 << TCP_CONN_##sym##_BIT, foreach_tcp_connection_flag #undef _ TCP_CONN_N_FLAGS } tcp_connection_flags_e; /** TCP buffer flags */ #define foreach_tcp_buf_flag \ _ (ACK) /**< Sending ACK. */ \ _ (DUPACK) /**< Sending DUPACK. */ \ enum { #define _(f) TCP_BUF_BIT_##f, foreach_tcp_buf_flag #undef _ TCP_N_BUF_BITS, }; enum { #define _(f) TCP_BUF_FLAG_##f = 1 << TCP_BUF_BIT_##f, foreach_tcp_buf_flag #undef _ }; #define TCP_MAX_SACK_BLOCKS 5 /**< Max number of SACK blocks stored */ #define TCP_INVALID_SACK_HOLE_INDEX ((u32)~0) typedef struct _sack_scoreboard_hole { u32 next; /**< Index for next entry in linked list */ u32 prev; /**< Index for previous entry in linked list */ u32 start; /**< Start sequence number */ u32 end; /**< End sequence number */ } sack_scoreboard_hole_t; typedef struct _sack_scoreboard { sack_scoreboard_hole_t *holes; /**< Pool of holes */ u32 head; /**< Index of first entry */ u32 tail; /**< Index of last entry */ u32 sacked_bytes; /**< Number of bytes sacked in sb */ u32 last_sacked_bytes; /**< Number of bytes last sacked */ u32 snd_una_adv; /**< Bytes to add to snd_una */ u32 max_byte_sacked; /**< Highest byte acked */ } sack_scoreboard_t; typedef enum _tcp_cc_algorithm_type { TCP_CC_NEWRENO, } tcp_cc_algorithm_type_e; typedef struct _tcp_cc_algorithm tcp_cc_algorithm_t; typedef enum _tcp_cc_ack_t { TCP_CC_ACK, TCP_CC_DUPACK, TCP_CC_PARTIALACK } tcp_cc_ack_t; typedef struct _tcp_connection { transport_connection_t connection; /**< Common transport data. First! */ u8 state; /**< TCP state as per tcp_state_t */ u16 flags; /**< Connection flags (see tcp_conn_flags_e) */ u32 timers[TCP_N_TIMERS]; /**< Timer handles into timer wheel */ /* TODO RFC4898 */ /** Send sequence variables RFC793 */ u32 snd_una; /**< oldest unacknowledged sequence number */ u32 snd_una_max; /**< newest unacknowledged sequence number + 1*/ u32 snd_wnd; /**< send window */ u32 snd_wl1; /**< seq number used for last snd.wnd update */ u32 snd_wl2; /**< ack number used for last snd.wnd update */ u32 snd_nxt; /**< next seq number to be sent */ /** Receive sequence variables RFC793 */ u32 rcv_nxt; /**< next sequence number expected */ u32 rcv_wnd; /**< receive window we expect */ u32 rcv_las; /**< rcv_nxt at last ack sent/rcv_wnd update */ u32 iss; /**< initial sent sequence */ u32 irs; /**< initial remote sequence */ /* Options */ tcp_options_t opt; /**< TCP connection options parsed */ tcp_options_t snd_opts; /**< Tx options for connection */ u8 snd_opts_len; /**< Tx options len */ u8 rcv_wscale; /**< Window scale to advertise to peer */ u8 snd_wscale; /**< Window scale to use when sending */ u32 tsval_recent; /**< Last timestamp received */ u32 tsval_recent_age; /**< When last updated tstamp_recent*/ sack_block_t *snd_sacks; /**< Vector of SACKs to send. XXX Fixed size? */ sack_scoreboard_t sack_sb; /**< SACK "scoreboard" that tracks holes */ u16 rcv_dupacks; /**< Number of DUPACKs received */ u8 snt_dupacks; /**< Number of DUPACKs sent in a burst */ /* Congestion control */ u32 cwnd; /**< Congestion window */ u32 ssthresh; /**< Slow-start threshold */ u32 prev_ssthresh; /**< ssthresh before congestion */ u32 bytes_acked; /**< Bytes acknowledged by current segment */ u32 rtx_bytes; /**< Retransmitted bytes */ u32 tsecr_last_ack; /**< Timestamp echoed to us in last healthy ACK */ u32 snd_congestion; /**< snd_una_max when congestion is detected */ tcp_cc_algorithm_t *cc_algo; /**< Congestion control algorithm */ /* RTT and RTO */ u32 rto; /**< Retransmission timeout */ u32 rto_boff; /**< Index for RTO backoff */ u32 srtt; /**< Smoothed RTT */ u32 rttvar; /**< Smoothed mean RTT difference. Approximates variance */ u32 rtt_ts; /**< Timestamp for tracked ACK */ u32 rtt_seq; /**< Sequence number for tracked ACK */ u16 snd_mss; /**< Effective send max seg (data) size */ u16 mss; /**< Our max seg size that includes options */ } tcp_connection_t; struct _tcp_cc_algorithm { void (*rcv_ack) (tcp_connection_t * tc); void (*rcv_cong_ack) (tcp_connection_t * tc, tcp_cc_ack_t ack); void (*congestion) (tcp_connection_t * tc); void (*recovered) (tcp_connection_t * tc); void (*init) (tcp_connection_t * tc); }; #define tcp_fastrecovery_on(tc) (tc)->flags |= TCP_CONN_FAST_RECOVERY #define tcp_fastrecovery_off(tc) (tc)->flags &= ~TCP_CONN_FAST_RECOVERY #define tcp_recovery_on(tc) (tc)->flags |= TCP_CONN_RECOVERY #define tcp_recovery_off(tc) (tc)->flags &= ~TCP_CONN_RECOVERY #define tcp_in_fastrecovery(tc) ((tc)->flags & TCP_CONN_FAST_RECOVERY) #define tcp_in_recovery(tc) ((tc)->flags & (TCP_CONN_RECOVERY)) #define tcp_in_slowstart(tc) (tc->cwnd < tc->ssthresh) #define tcp_fastrecovery_sent_1_smss(tc) ((tc)->flags & TCP_CONN_FR_1_SMSS) #define tcp_fastrecovery_1_smss_on(tc) ((tc)->flags |= TCP_CONN_FR_1_SMSS) #define tcp_fastrecovery_1_smss_off(tc) ((tc)->flags &= ~TCP_CONN_FR_1_SMSS) #define tcp_in_cong_recovery(tc) ((tc)->flags & \ (TCP_CONN_FAST_RECOVERY | TCP_CONN_RECOVERY)) always_inline void tcp_cong_recovery_off (tcp_connection_t * tc) { tc->flags &= ~(TCP_CONN_FAST_RECOVERY | TCP_CONN_RECOVERY); tcp_fastrecovery_1_smss_off (tc); } typedef enum { TCP_IP4, TCP_IP6, TCP_N_AF, } tcp_af_t; typedef enum _tcp_error { #define tcp_error(n,s) TCP_ERROR_##n, #include <vnet/tcp/tcp_error.def> #undef tcp_error TCP_N_ERROR, } tcp_error_t; typedef struct _tcp_lookup_dispatch { u8 next, error; } tcp_lookup_dispatch_t; typedef struct _tcp_main { /* Per-worker thread tcp connection pools */ tcp_connection_t **connections; /* Pool of listeners. */ tcp_connection_t *listener_pool; /** Dispatch table by state and flags */ tcp_lookup_dispatch_t dispatch_table[TCP_N_STATES][64]; u8 log2_tstamp_clocks_per_tick; f64 tstamp_ticks_per_clock; /** per-worker tx buffer free lists */ u32 **tx_buffers; /* Per worker-thread timer wheel for connections timers */ tw_timer_wheel_16t_2w_512sl_t *timer_wheels; // /* Convenience per worker-thread vector of connections to DELACK */ // u32 **delack_connections; /* Pool of half-open connections on which we've sent a SYN */ tcp_connection_t *half_open_connections; /* Pool of local TCP endpoints */ transport_endpoint_t *local_endpoints; /* Local endpoints lookup table */ transport_endpoint_table_t local_endpoints_table; /* Congestion control algorithms registered */ tcp_cc_algorithm_t *cc_algos; /* Flag that indicates if stack is on or off */ u8 is_enabled; /* convenience */ vlib_main_t *vlib_main; vnet_main_t *vnet_main; ip4_main_t *ip4_main; ip6_main_t *ip6_main; } tcp_main_t; extern tcp_main_t tcp_main; extern vlib_node_registration_t tcp4_input_node; extern vlib_node_registration_t tcp6_input_node; extern vlib_node_registration_t tcp4_output_node; extern vlib_node_registration_t tcp6_output_node; always_inline tcp_main_t * vnet_get_tcp_main () { return &tcp_main; } always_inline tcp_header_t * tcp_buffer_hdr (vlib_buffer_t * b) { ASSERT ((signed) b->current_data >= (signed) -VLIB_BUFFER_PRE_DATA_SIZE); return (tcp_header_t *) (b->data + b->current_data + vnet_buffer (b)->tcp.hdr_offset); } clib_error_t *vnet_tcp_enable_disable (vlib_main_t * vm, u8 is_en); always_inline tcp_connection_t * tcp_connection_get (u32 conn_index, u32 thread_index) { if (pool_is_free_index (tcp_main.connections[thread_index], conn_index)) return 0; return pool_elt_at_index (tcp_main.connections[thread_index], conn_index); } always_inline tcp_connection_t * tcp_connection_get_if_valid (u32 conn_index, u32 thread_index) { if (tcp_main.connections[thread_index] == 0) return 0; if (pool_is_free_index (tcp_main.connections[thread_index], conn_index)) return 0; return pool_elt_at_index (tcp_main.connections[thread_index], conn_index); } void tcp_connection_close (tcp_connection_t * tc); void tcp_connection_cleanup (tcp_connection_t * tc); void tcp_connection_del (tcp_connection_t * tc); void tcp_connection_reset (tcp_connection_t * tc); u8 *format_tcp_connection_id (u8 * s, va_list * args); u8 *format_tcp_connection (u8 * s, va_list * args); u8 *format_tcp_scoreboard (u8 * s, va_list * args); always_inline tcp_connection_t * tcp_listener_get (u32 tli) { return pool_elt_at_index (tcp_main.listener_pool, tli); } always_inline tcp_connection_t * tcp_half_open_connection_get (u32 conn_index) { return pool_elt_at_index (tcp_main.half_open_connections, conn_index); } void tcp_make_ack (tcp_connection_t * ts, vlib_buffer_t * b); void tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b); void tcp_make_synack (tcp_connection_t * ts, vlib_buffer_t * b); void tcp_send_reset (vlib_buffer_t * pkt, u8 is_ip4); void tcp_send_syn (tcp_connection_t * tc); void tcp_send_fin (tcp_connection_t * tc); void tcp_init_mss (tcp_connection_t * tc); void tcp_update_snd_mss (tcp_connection_t * tc); always_inline u32 tcp_end_seq (tcp_header_t * th, u32 len) { return th->seq_number + tcp_is_syn (th) + tcp_is_fin (th) + len; } /* Modulo arithmetic for TCP sequence numbers */ #define seq_lt(_s1, _s2) ((i32)((_s1)-(_s2)) < 0) #define seq_leq(_s1, _s2) ((i32)((_s1)-(_s2)) <= 0) #define seq_gt(_s1, _s2) ((i32)((_s1)-(_s2)) > 0) #define seq_geq(_s1, _s2) ((i32)((_s1)-(_s2)) >= 0) /* Modulo arithmetic for timestamps */ #define timestamp_lt(_t1, _t2) ((i32)((_t1)-(_t2)) < 0) #define timestamp_leq(_t1, _t2) ((i32)((_t1)-(_t2)) <= 0) always_inline u32 tcp_flight_size (const tcp_connection_t * tc) { int flight_size; flight_size = (int) ((tc->snd_una_max - tc->snd_una) + tc->rtx_bytes) - (tc->rcv_dupacks * tc->snd_mss) /* - tc->sack_sb.sacked_bytes */ ; /* Happens if we don't clear sacked bytes */ if (flight_size < 0) return 0; return flight_size; } /** * Initial cwnd as per RFC5681 */ always_inline u32 tcp_initial_cwnd (const tcp_connection_t * tc) { if (tc->snd_mss > 2190) return 2 * tc->snd_mss; else if (tc->snd_mss > 1095) return 3 * tc->snd_mss; else return 4 * tc->snd_mss; } always_inline u32 tcp_loss_wnd (const tcp_connection_t * tc) { return tc->snd_mss; } always_inline u32 tcp_available_wnd (const tcp_connection_t * tc) { return clib_min (tc->cwnd, tc->snd_wnd); } always_inline u32 tcp_available_snd_space (const tcp_connection_t * tc) { u32 available_wnd = tcp_available_wnd (tc); u32 flight_size = tcp_flight_size (tc); if (available_wnd <= flight_size) return 0; return available_wnd - flight_size; } u32 tcp_rcv_wnd_available (tcp_connection_t * tc); u32 tcp_snd_space (tcp_connection_t * tc); void tcp_update_rcv_wnd (tcp_connection_t * tc); void tcp_retransmit_first_unacked (tcp_connection_t * tc); void tcp_fast_retransmit (tcp_connection_t * tc); void tcp_cc_congestion (tcp_connection_t * tc); void tcp_cc_recover (tcp_connection_t * tc); /* Made public for unit testing only */ void tcp_update_sack_list (tcp_connection_t * tc, u32 start, u32 end); always_inline u32 tcp_time_now (void) { return clib_cpu_time_now () * tcp_main.tstamp_ticks_per_clock; } always_inline void tcp_update_time (f64 now, u32 thread_index) { tw_timer_expire_timers_16t_2w_512sl (&tcp_main.timer_wheels[thread_index], now); } u32 tcp_push_header (transport_connection_t * tconn, vlib_buffer_t * b); u32 tcp_prepare_retransmit_segment (tcp_connection_t * tc, vlib_buffer_t * b, u32 offset, u32 max_bytes); void tcp_connection_timers_init (tcp_connection_t * tc); void tcp_connection_timers_reset (tcp_connection_t * tc); void tcp_connection_init_vars (tcp_connection_t * tc); always_inline void tcp_connection_force_ack (tcp_connection_t * tc, vlib_buffer_t * b) { /* Reset flags, make sure ack is sent */ tc->flags = TCP_CONN_SNDACK; vnet_buffer (b)->tcp.flags &= ~TCP_BUF_FLAG_DUPACK; } always_inline void tcp_timer_set (tcp_connection_t * tc, u8 timer_id, u32 interval) { tc->timers[timer_id] = tw_timer_start_16t_2w_512sl (&tcp_main.timer_wheels[tc->c_thread_index], tc->c_c_index, timer_id, interval); } always_inline void tcp_timer_reset (tcp_connection_t * tc, u8 timer_id) { if (tc->timers[timer_id] == TCP_TIMER_HANDLE_INVALID) return; tw_timer_stop_16t_2w_512sl (&tcp_main.timer_wheels[tc->c_thread_index], tc->timers[timer_id]); tc->timers[timer_id] = TCP_TIMER_HANDLE_INVALID; } always_inline void tcp_timer_update (tcp_connection_t * tc, u8 timer_id, u32 interval) { if (tc->timers[timer_id] != TCP_TIMER_HANDLE_INVALID) tw_timer_stop_16t_2w_512sl (&tcp_main.timer_wheels[tc->c_thread_index], tc->timers[timer_id]); tc->timers[timer_id] = tw_timer_start_16t_2w_512sl (&tcp_main.timer_wheels[tc->c_thread_index], tc->c_c_index, timer_id, interval); } /* XXX Switch retransmit to faster TW */ always_inline void tcp_retransmit_timer_set (tcp_connection_t * tc) { tcp_timer_set (tc, TCP_TIMER_RETRANSMIT, clib_max (tc->rto * TCP_TO_TIMER_TICK, 1)); } always_inline void tcp_retransmit_timer_update (tcp_connection_t * tc) { tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, clib_max (tc->rto * TCP_TO_TIMER_TICK, 1)); } always_inline void tcp_retransmit_timer_reset (tcp_connection_t * tc) { tcp_timer_reset (tc, TCP_TIMER_RETRANSMIT); } always_inline void tcp_persist_timer_set (tcp_connection_t * tc) { /* Reuse RTO. It's backed off in handler */ tcp_timer_set (tc, TCP_TIMER_PERSIST, clib_max (tc->rto * TCP_TO_TIMER_TICK, TCP_TIMER_PERSIST_MIN)); } always_inline void tcp_persist_timer_update (tcp_connection_t * tc) { tcp_timer_update (tc, TCP_TIMER_PERSIST, clib_max (tc->rto * TCP_TO_TIMER_TICK, TCP_TIMER_PERSIST_MIN)); } always_inline void tcp_persist_timer_reset (tcp_connection_t * tc) { tcp_timer_reset (tc, TCP_TIMER_PERSIST); } always_inline u8 tcp_timer_is_active (tcp_connection_t * tc, tcp_timers_e timer) { return tc->timers[timer] != TCP_TIMER_HANDLE_INVALID; } void scoreboard_remove_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole); always_inline sack_scoreboard_hole_t * scoreboard_get_hole (sack_scoreboard_t * sb, u32 index) { if (index != TCP_INVALID_SACK_HOLE_INDEX) return pool_elt_at_index (sb->holes, index); return 0; } always_inline sack_scoreboard_hole_t * scoreboard_next_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole) { if (hole->next != TCP_INVALID_SACK_HOLE_INDEX) return pool_elt_at_index (sb->holes, hole->next); return 0; } always_inline sack_scoreboard_hole_t * scoreboard_first_hole (sack_scoreboard_t * sb) { if (sb->head != TCP_INVALID_SACK_HOLE_INDEX) return pool_elt_at_index (sb->holes, sb->head); return 0; } always_inline sack_scoreboard_hole_t * scoreboard_last_hole (sack_scoreboard_t * sb) { if (sb->tail != TCP_INVALID_SACK_HOLE_INDEX) return pool_elt_at_index (sb->holes, sb->tail); return 0; } always_inline void scoreboard_clear (sack_scoreboard_t * sb) { sack_scoreboard_hole_t *hole = scoreboard_first_hole (sb); while ((hole = scoreboard_first_hole (sb))) { scoreboard_remove_hole (sb, hole); } sb->sacked_bytes = 0; sb->last_sacked_bytes = 0; sb->snd_una_adv = 0; sb->max_byte_sacked = 0; } always_inline u32 scoreboard_hole_bytes (sack_scoreboard_hole_t * hole) { return hole->end - hole->start; } always_inline u32 scoreboard_hole_index (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole) { return hole - sb->holes; } always_inline void scoreboard_init (sack_scoreboard_t * sb) { sb->head = TCP_INVALID_SACK_HOLE_INDEX; sb->tail = TCP_INVALID_SACK_HOLE_INDEX; } void tcp_rcv_sacks (tcp_connection_t * tc, u32 ack); always_inline void tcp_cc_algo_register (tcp_cc_algorithm_type_e type, const tcp_cc_algorithm_t * vft) { tcp_main_t *tm = vnet_get_tcp_main (); vec_validate (tm->cc_algos, type); tm->cc_algos[type] = *vft; } always_inline tcp_cc_algorithm_t * tcp_cc_algo_get (tcp_cc_algorithm_type_e type) { tcp_main_t *tm = vnet_get_tcp_main (); return &tm->cc_algos[type]; } void tcp_cc_init (tcp_connection_t * tc); /** * Push TCP header to buffer * * @param vm - vlib_main * @param b - buffer to write the header to * @param sp_net - source port net order * @param dp_net - destination port net order * @param seq - sequence number net order * @param ack - ack number net order * @param tcp_hdr_opts_len - header and options length in bytes * @param flags - header flags * @param wnd - window size * * @return - pointer to start of TCP header */ always_inline void * vlib_buffer_push_tcp_net_order (vlib_buffer_t * b, u16 sp, u16 dp, u32 seq, u32 ack, u8 tcp_hdr_opts_len, u8 flags, u16 wnd) { tcp_header_t *th; th = vlib_buffer_push_uninit (b, tcp_hdr_opts_len); th->src_port = sp; th->dst_port = dp; th->seq_number = seq; th->ack_number = ack; th->data_offset_and_reserved = (tcp_hdr_opts_len >> 2) << 4; th->flags = flags; th->window = wnd; th->checksum = 0; th->urgent_pointer = 0; return th; } /** * Push TCP header to buffer * * @param b - buffer to write the header to * @param sp_net - source port net order * @param dp_net - destination port net order * @param seq - sequence number host order * @param ack - ack number host order * @param tcp_hdr_opts_len - header and options length in bytes * @param flags - header flags * @param wnd - window size * * @return - pointer to start of TCP header */ always_inline void * vlib_buffer_push_tcp (vlib_buffer_t * b, u16 sp_net, u16 dp_net, u32 seq, u32 ack, u8 tcp_hdr_opts_len, u8 flags, u16 wnd) { return vlib_buffer_push_tcp_net_order (b, sp_net, dp_net, clib_host_to_net_u32 (seq), clib_host_to_net_u32 (ack), tcp_hdr_opts_len, flags, clib_host_to_net_u16 (wnd)); } #endif /* _vnet_tcp_h_ */ /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */