X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=src%2Fvnet%2Ftcp%2Ftcp_output.c;h=4b7915828df3b90c8bc0cdfe41eac99f7008ae3c;hb=6080e0d15e152e38811b01306eef6719a682c007;hp=33e599ece32c1b942284cafcf4afe82f4a7c2f13;hpb=f6d68ed2db2bcd41c9b7ddde5e411073c1566c29;p=vpp.git diff --git a/src/vnet/tcp/tcp_output.c b/src/vnet/tcp/tcp_output.c index 33e599ece32..d33cbdd4ad4 100644 --- a/src/vnet/tcp/tcp_output.c +++ b/src/vnet/tcp/tcp_output.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 2016 Cisco and/or its affiliates. + * Copyright (c) 2016-2019 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: @@ -14,25 +14,28 @@ */ #include -#include +#include -vlib_node_registration_t tcp4_output_node; -vlib_node_registration_t tcp6_output_node; - -typedef enum _tcp_output_nect +typedef enum _tcp_output_next { TCP_OUTPUT_NEXT_DROP, TCP_OUTPUT_NEXT_IP_LOOKUP, + TCP_OUTPUT_NEXT_IP_REWRITE, + TCP_OUTPUT_NEXT_IP_ARP, TCP_OUTPUT_N_NEXT } tcp_output_next_t; #define foreach_tcp4_output_next \ _ (DROP, "error-drop") \ - _ (IP_LOOKUP, "ip4-lookup") + _ (IP_LOOKUP, "ip4-lookup") \ + _ (IP_REWRITE, "ip4-rewrite") \ + _ (IP_ARP, "ip4-arp") #define foreach_tcp6_output_next \ _ (DROP, "error-drop") \ - _ (IP_LOOKUP, "ip6-lookup") + _ (IP_LOOKUP, "ip6-lookup") \ + _ (IP_REWRITE, "ip6-rewrite") \ + _ (IP_ARP, "ip6-discover-neighbor") static char *tcp_error_strings[] = { #define tcp_error(n,s) s, @@ -46,41 +49,48 @@ typedef struct tcp_connection_t tcp_connection; } tcp_tx_trace_t; -u16 dummy_mtu = 1460; - -u8 * +static u8 * format_tcp_tx_trace (u8 * s, va_list * args) { CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *); CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *); tcp_tx_trace_t *t = va_arg (*args, tcp_tx_trace_t *); - uword indent = format_get_indent (s); + tcp_connection_t *tc = &t->tcp_connection; + u32 indent = format_get_indent (s); - s = format (s, "%U\n%U%U", - format_tcp_header, &t->tcp_header, 128, - format_white_space, indent, - format_tcp_connection_verbose, &t->tcp_connection); + s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc, + format_tcp_state, tc->state, format_white_space, indent, + format_tcp_header, &t->tcp_header, 128); return s; } +#ifndef CLIB_MARCH_VARIANT static u8 -tcp_window_compute_scale (u32 available_space) +tcp_window_compute_scale (u32 window) { u8 wnd_scale = 0; - while (wnd_scale < TCP_MAX_WND_SCALE - && (available_space >> wnd_scale) > TCP_WND_MAX) + while (wnd_scale < TCP_MAX_WND_SCALE && (window >> wnd_scale) > TCP_WND_MAX) wnd_scale++; return wnd_scale; } /** - * TCP's IW as recommended by RFC6928 + * TCP's initial window */ always_inline u32 tcp_initial_wnd_unscaled (tcp_connection_t * tc) { - return TCP_IW_N_SEGMENTS * tc->mss; + /* RFC 6928 recommends the value lower. However at the time our connections + * are initialized, fifos may not be allocated. Therefore, advertise the + * smallest possible unscaled window size and update once fifos are + * assigned to the session. + */ + /* + tcp_update_rcv_mss (tc); + TCP_IW_N_SEGMENTS * tc->mss; + */ + return tcp_cfg.min_rx_fifo; } /** @@ -90,71 +100,44 @@ tcp_initial_wnd_unscaled (tcp_connection_t * tc) u32 tcp_initial_window_to_advertise (tcp_connection_t * tc) { - u32 max_fifo; - - /* Initial wnd for SYN. Fifos are not allocated yet. - * Use some predefined value. For SYN-ACK we still want the - * scale to be computed in the same way */ - max_fifo = TCP_MAX_RX_FIFO_SIZE; + /* Compute rcv wscale only if peer advertised support for it */ + if (tc->state != TCP_STATE_SYN_RCVD || tcp_opts_wscale (&tc->rcv_opts)) + tc->rcv_wscale = tcp_window_compute_scale (tcp_cfg.max_rx_fifo); - tc->rcv_wscale = tcp_window_compute_scale (max_fifo); tc->rcv_wnd = tcp_initial_wnd_unscaled (tc); return clib_min (tc->rcv_wnd, TCP_WND_MAX); } -/** - * Compute and return window to advertise, scaled as per RFC1323 - */ -u32 -tcp_window_to_advertise (tcp_connection_t * tc, tcp_state_t state) -{ - if (state < TCP_STATE_ESTABLISHED) - return tcp_initial_window_to_advertise (tc); - - tcp_update_rcv_wnd (tc); - - if (tc->rcv_wnd == 0) - { - tc->flags |= TCP_CONN_SENT_RCV_WND0; - } - else - { - tc->flags &= ~TCP_CONN_SENT_RCV_WND0; - } - - return tc->rcv_wnd >> tc->rcv_wscale; -} - -void +static inline void tcp_update_rcv_wnd (tcp_connection_t * tc) { + u32 available_space, wnd; i32 observed_wnd; - u32 available_space, max_fifo, wnd; + + ASSERT (tc->rcv_opts.mss < transport_rx_fifo_size (&tc->connection)); /* * Figure out how much space we have available */ - available_space = stream_session_max_rx_enqueue (&tc->connection); - max_fifo = stream_session_fifo_size (&tc->connection); - - ASSERT (tc->opt.mss < max_fifo); - if (available_space < tc->opt.mss && available_space < max_fifo >> 3) - available_space = 0; + available_space = transport_max_rx_enqueue (&tc->connection); + if (PREDICT_FALSE (available_space < tc->rcv_opts.mss)) + { + tc->rcv_wnd = 0; + return; + } /* * Use the above and what we know about what we've previously advertised * to compute the new window */ observed_wnd = (i32) tc->rcv_wnd - (tc->rcv_nxt - tc->rcv_las); - if (observed_wnd < 0) - observed_wnd = 0; /* Bad. Thou shalt not shrink */ - if (available_space < observed_wnd) + if (PREDICT_FALSE ((i32) available_space < observed_wnd)) { - wnd = observed_wnd; - TCP_EVT_DBG (TCP_EVT_RCV_WND_SHRUNK, tc, observed_wnd, available_space); + wnd = clib_max (observed_wnd, 0); + TCP_EVT (TCP_EVT_RCV_WND_SHRUNK, tc, observed_wnd, available_space); } else { @@ -164,7 +147,7 @@ tcp_update_rcv_wnd (tcp_connection_t * tc) /* Make sure we have a multiple of rcv_wscale */ if (wnd && tc->rcv_wscale) { - wnd &= ~(1 << tc->rcv_wscale); + wnd &= ~((1 << tc->rcv_wscale) - 1); if (wnd == 0) wnd = 1 << tc->rcv_wscale; } @@ -172,10 +155,23 @@ tcp_update_rcv_wnd (tcp_connection_t * tc) tc->rcv_wnd = clib_min (wnd, TCP_WND_MAX << tc->rcv_wscale); } +/** + * Compute and return window to advertise, scaled as per RFC1323 + */ +static inline u32 +tcp_window_to_advertise (tcp_connection_t * tc, tcp_state_t state) +{ + if (state < TCP_STATE_ESTABLISHED) + return tcp_initial_window_to_advertise (tc); + + tcp_update_rcv_wnd (tc); + return tc->rcv_wnd >> tc->rcv_wscale; +} + /** * Write TCP options to segment. */ -u32 +static u32 tcp_options_write (u8 * data, tcp_options_t * opts) { u32 opts_len = 0; @@ -186,7 +182,7 @@ tcp_options_write (u8 * data, tcp_options_t * opts) *data++ = TCP_OPTION_MSS; *data++ = TCP_OPTION_LEN_MSS; buf = clib_host_to_net_u16 (opts->mss); - clib_memcpy (data, &buf, sizeof (opts->mss)); + clib_memcpy_fast (data, &buf, sizeof (opts->mss)); data += sizeof (opts->mss); opts_len += TCP_OPTION_LEN_MSS; } @@ -211,10 +207,10 @@ tcp_options_write (u8 * data, tcp_options_t * opts) *data++ = TCP_OPTION_TIMESTAMP; *data++ = TCP_OPTION_LEN_TIMESTAMP; buf = clib_host_to_net_u32 (opts->tsval); - clib_memcpy (data, &buf, sizeof (opts->tsval)); + clib_memcpy_fast (data, &buf, sizeof (opts->tsval)); data += sizeof (opts->tsval); buf = clib_host_to_net_u32 (opts->tsecr); - clib_memcpy (data, &buf, sizeof (opts->tsecr)); + clib_memcpy_fast (data, &buf, sizeof (opts->tsecr)); data += sizeof (opts->tsecr); opts_len += TCP_OPTION_LEN_TIMESTAMP; } @@ -222,23 +218,21 @@ tcp_options_write (u8 * data, tcp_options_t * opts) if (tcp_opts_sack (opts)) { int i; - u32 n_sack_blocks = clib_min (vec_len (opts->sacks), - TCP_OPTS_MAX_SACK_BLOCKS); - if (n_sack_blocks != 0) + if (opts->n_sack_blocks != 0) { *data++ = TCP_OPTION_SACK_BLOCK; - *data++ = 2 + n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK; - for (i = 0; i < n_sack_blocks; i++) + *data++ = 2 + opts->n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK; + for (i = 0; i < opts->n_sack_blocks; i++) { buf = clib_host_to_net_u32 (opts->sacks[i].start); - clib_memcpy (data, &buf, seq_len); + clib_memcpy_fast (data, &buf, seq_len); data += seq_len; buf = clib_host_to_net_u32 (opts->sacks[i].end); - clib_memcpy (data, &buf, seq_len); + clib_memcpy_fast (data, &buf, seq_len); data += seq_len; } - opts_len += 2 + n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK; + opts_len += 2 + opts->n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK; } } @@ -258,17 +252,17 @@ tcp_options_write (u8 * data, tcp_options_t * opts) return opts_len; } -always_inline int -tcp_make_syn_options (tcp_options_t * opts, u8 wnd_scale) +static int +tcp_make_syn_options (tcp_connection_t * tc, tcp_options_t * opts) { u8 len = 0; opts->flags |= TCP_OPTS_FLAG_MSS; - opts->mss = dummy_mtu; /*XXX discover that */ + opts->mss = tc->mss; len += TCP_OPTION_LEN_MSS; opts->flags |= TCP_OPTS_FLAG_WSCALE; - opts->wscale = wnd_scale; + opts->wscale = tc->rcv_wscale; len += TCP_OPTION_LEN_WINDOW_SCALE; opts->flags |= TCP_OPTS_FLAG_TSTAMP; @@ -276,15 +270,18 @@ tcp_make_syn_options (tcp_options_t * opts, u8 wnd_scale) opts->tsecr = 0; len += TCP_OPTION_LEN_TIMESTAMP; - opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED; - len += TCP_OPTION_LEN_SACK_PERMITTED; + if (TCP_USE_SACKS) + { + opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED; + len += TCP_OPTION_LEN_SACK_PERMITTED; + } /* Align to needed boundary */ len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN; return len; } -always_inline int +static int tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts) { u8 len = 0; @@ -293,14 +290,14 @@ tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts) opts->mss = tc->mss; len += TCP_OPTION_LEN_MSS; - if (tcp_opts_wscale (&tc->opt)) + if (tcp_opts_wscale (&tc->rcv_opts)) { opts->flags |= TCP_OPTS_FLAG_WSCALE; opts->wscale = tc->rcv_wscale; len += TCP_OPTION_LEN_WINDOW_SCALE; } - if (tcp_opts_tstamp (&tc->opt)) + if (tcp_opts_tstamp (&tc->rcv_opts)) { opts->flags |= TCP_OPTS_FLAG_TSTAMP; opts->tsval = tcp_time_now (); @@ -308,7 +305,7 @@ tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts) len += TCP_OPTION_LEN_TIMESTAMP; } - if (tcp_opts_sack_permitted (&tc->opt)) + if (tcp_opts_sack_permitted (&tc->rcv_opts)) { opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED; len += TCP_OPTION_LEN_SACK_PERMITTED; @@ -319,28 +316,32 @@ tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts) return len; } -always_inline int +static int tcp_make_established_options (tcp_connection_t * tc, tcp_options_t * opts) { u8 len = 0; opts->flags = 0; - if (tcp_opts_tstamp (&tc->opt)) + if (tcp_opts_tstamp (&tc->rcv_opts)) { opts->flags |= TCP_OPTS_FLAG_TSTAMP; - opts->tsval = tcp_time_now (); + opts->tsval = tcp_tstamp (tc); opts->tsecr = tc->tsval_recent; len += TCP_OPTION_LEN_TIMESTAMP; } - if (tcp_opts_sack_permitted (&tc->opt)) + if (tcp_opts_sack_permitted (&tc->rcv_opts)) { if (vec_len (tc->snd_sacks)) { opts->flags |= TCP_OPTS_FLAG_SACK; - opts->sacks = tc->snd_sacks; - opts->n_sack_blocks = clib_min (vec_len (tc->snd_sacks), + if (tc->snd_sack_pos >= vec_len (tc->snd_sacks)) + tc->snd_sack_pos = 0; + opts->sacks = &tc->snd_sacks[tc->snd_sack_pos]; + opts->n_sack_blocks = vec_len (tc->snd_sacks) - tc->snd_sack_pos; + opts->n_sack_blocks = clib_min (opts->n_sack_blocks, TCP_OPTS_MAX_SACK_BLOCKS); + tc->snd_sack_pos += opts->n_sack_blocks; len += 2 + TCP_OPTION_LEN_SACK_BLOCK * opts->n_sack_blocks; } } @@ -357,120 +358,170 @@ tcp_make_options (tcp_connection_t * tc, tcp_options_t * opts, switch (state) { case TCP_STATE_ESTABLISHED: + case TCP_STATE_CLOSE_WAIT: case TCP_STATE_FIN_WAIT_1: + case TCP_STATE_LAST_ACK: + case TCP_STATE_CLOSING: + case TCP_STATE_FIN_WAIT_2: + case TCP_STATE_TIME_WAIT: + case TCP_STATE_CLOSED: return tcp_make_established_options (tc, opts); case TCP_STATE_SYN_RCVD: return tcp_make_synack_options (tc, opts); case TCP_STATE_SYN_SENT: - return tcp_make_syn_options (opts, tc->rcv_wscale); + return tcp_make_syn_options (tc, opts); default: - clib_warning ("Not handled!"); + clib_warning ("State not handled! %d", state); return 0; } } /** - * Update max segment size we're able to process. + * Update burst send vars + * + * - Updates snd_mss to reflect the effective segment size that we can send + * by taking into account all TCP options, including SACKs. + * - Cache 'on the wire' options for reuse + * - Updates receive window which can be reused for a burst. * - * The value is constrained by our interface's MTU and IP options. It is - * also what we advertise to our peer. + * This should *only* be called when doing bursts */ void -tcp_update_rcv_mss (tcp_connection_t * tc) +tcp_update_burst_snd_vars (tcp_connection_t * tc) { - /* TODO find our iface MTU */ - tc->mss = dummy_mtu; -} + tcp_main_t *tm = &tcp_main; -/** - * Update snd_mss to reflect the effective segment size that we can send - * by taking into account all TCP options, including SACKs - */ -void -tcp_update_snd_mss (tcp_connection_t * tc) -{ /* Compute options to be used for connection. These may be reused when * sending data or to compute the effective mss (snd_mss) */ - tc->snd_opts_len = - tcp_make_options (tc, &tc->snd_opts, TCP_STATE_ESTABLISHED); + tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, + TCP_STATE_ESTABLISHED); /* XXX check if MTU has been updated */ - tc->snd_mss = clib_min (tc->mss, tc->opt.mss) - tc->snd_opts_len; + tc->snd_mss = clib_min (tc->mss, tc->rcv_opts.mss) - tc->snd_opts_len; + ASSERT (tc->snd_mss > 0); + + tcp_options_write (tm->wrk_ctx[tc->c_thread_index].cached_opts, + &tc->snd_opts); + + tcp_update_rcv_wnd (tc); + + if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE) + tcp_bt_check_app_limited (tc); + + if (tc->snd_una == tc->snd_nxt) + { + tcp_cc_event (tc, TCP_CC_EVT_START_TX); + tcp_connection_tx_pacer_reset (tc, tc->cwnd, TRANSPORT_PACER_MIN_BURST); + } } -void -tcp_init_mss (tcp_connection_t * tc) -{ - tcp_update_rcv_mss (tc); - - /* TODO cache mss and consider PMTU discovery */ - tc->snd_mss = clib_min (tc->opt.mss, tc->mss); - - if (tc->snd_mss == 0) - { - clib_warning ("snd mss is 0"); - tc->snd_mss = tc->mss; - } - - /* We should have enough space for 40 bytes of options */ - ASSERT (tc->snd_mss > 45); - - /* If we use timestamp option, account for it */ - if (tcp_opts_tstamp (&tc->opt)) - tc->snd_mss -= TCP_OPTION_LEN_TIMESTAMP; -} - -#define tcp_get_free_buffer_index(tm, bidx) \ -do { \ - u32 *my_tx_buffers, n_free_buffers; \ - u32 thread_index = vlib_get_thread_index(); \ - my_tx_buffers = tm->tx_buffers[thread_index]; \ - if (PREDICT_FALSE(vec_len (my_tx_buffers) == 0)) \ - { \ - n_free_buffers = 32; /* TODO config or macro */ \ - vec_validate (my_tx_buffers, n_free_buffers - 1); \ - _vec_len(my_tx_buffers) = vlib_buffer_alloc_from_free_list ( \ - tm->vlib_main, my_tx_buffers, n_free_buffers, \ - VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX); \ - tm->tx_buffers[thread_index] = my_tx_buffers; \ - } \ - /* buffer shortage */ \ - if (PREDICT_FALSE (vec_len (my_tx_buffers) == 0)) \ - return; \ - *bidx = my_tx_buffers[_vec_len (my_tx_buffers)-1]; \ - _vec_len (my_tx_buffers) -= 1; \ -} while (0) - -#define tcp_return_buffer(tm) \ -do { \ - u32 *my_tx_buffers; \ - u32 thread_index = vlib_get_thread_index(); \ - my_tx_buffers = tm->tx_buffers[thread_index]; \ - _vec_len (my_tx_buffers) +=1; \ -} while (0) +#endif /* CLIB_MARCH_VARIANT */ -always_inline void +static void * tcp_reuse_buffer (vlib_main_t * vm, vlib_buffer_t * b) { - vlib_buffer_t *it = b; - do - { - it->current_data = 0; - it->current_length = 0; - it->total_length_not_including_first_buffer = 0; - } - while ((it->flags & VLIB_BUFFER_NEXT_PRESENT) - && (it = vlib_get_buffer (vm, it->next_buffer))); + if (b->flags & VLIB_BUFFER_NEXT_PRESENT) + vlib_buffer_free_one (vm, b->next_buffer); + /* Zero all flags but free list index and trace flag */ + b->flags &= VLIB_BUFFER_NEXT_PRESENT - 1; + b->current_data = 0; + b->current_length = 0; + b->total_length_not_including_first_buffer = 0; + vnet_buffer (b)->tcp.flags = 0; /* Leave enough space for headers */ - vlib_buffer_make_headroom (b, MAX_HDRS_LEN); + return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN); +} + +#ifndef CLIB_MARCH_VARIANT +static void * +tcp_init_buffer (vlib_main_t * vm, vlib_buffer_t * b) +{ + ASSERT ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0); + b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED; + b->total_length_not_including_first_buffer = 0; + b->current_data = 0; vnet_buffer (b)->tcp.flags = 0; + VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b); + /* Leave enough space for headers */ + return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN); +} + + +/* Compute TCP checksum in software when offloading is disabled for a connection */ +u16 +ip6_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0, + ip46_address_t * src, ip46_address_t * dst) +{ + ip_csum_t sum0; + u16 payload_length_host_byte_order; + u32 i; + + /* Initialize checksum with ip header. */ + sum0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, p0)) + + clib_host_to_net_u16 (IP_PROTOCOL_TCP); + payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0); + + for (i = 0; i < ARRAY_LEN (src->ip6.as_uword); i++) + { + sum0 = ip_csum_with_carry + (sum0, clib_mem_unaligned (&src->ip6.as_uword[i], uword)); + sum0 = ip_csum_with_carry + (sum0, clib_mem_unaligned (&dst->ip6.as_uword[i], uword)); + } + + return ip_calculate_l4_checksum (vm, p0, sum0, + payload_length_host_byte_order, NULL, 0, + NULL); +} + +u16 +ip4_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0, + ip46_address_t * src, ip46_address_t * dst) +{ + ip_csum_t sum0; + u32 payload_length_host_byte_order; + + payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0); + sum0 = + clib_host_to_net_u32 (payload_length_host_byte_order + + (IP_PROTOCOL_TCP << 16)); + + sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&src->ip4, u32)); + sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&dst->ip4, u32)); + + return ip_calculate_l4_checksum (vm, p0, sum0, + payload_length_host_byte_order, NULL, 0, + NULL); +} + +static inline u16 +tcp_compute_checksum (tcp_connection_t * tc, vlib_buffer_t * b) +{ + u16 checksum = 0; + if (PREDICT_FALSE (tc->cfg_flags & TCP_CFG_F_NO_CSUM_OFFLOAD)) + { + tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index); + vlib_main_t *vm = wrk->vm; + + if (tc->c_is_ip4) + checksum = ip4_tcp_compute_checksum_custom + (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip); + else + checksum = ip6_tcp_compute_checksum_custom + (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip); + } + else + { + b->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM; + } + return checksum; } /** * Prepare ACK */ -void +static inline void tcp_make_ack_i (tcp_connection_t * tc, vlib_buffer_t * b, tcp_state_t state, u8 flags) { @@ -489,21 +540,25 @@ tcp_make_ack_i (tcp_connection_t * tc, vlib_buffer_t * b, tcp_state_t state, tc->rcv_nxt, tcp_hdr_opts_len, flags, wnd); tcp_options_write ((u8 *) (th + 1), snd_opts); + + th->checksum = tcp_compute_checksum (tc, b); + vnet_buffer (b)->tcp.connection_index = tc->c_c_index; + + if (wnd == 0) + tcp_zero_rwnd_sent_on (tc); + else + tcp_zero_rwnd_sent_off (tc); } /** * Convert buffer to ACK */ -void +static inline void tcp_make_ack (tcp_connection_t * tc, vlib_buffer_t * b) { - vlib_main_t *vm = vlib_get_main (); - - tcp_reuse_buffer (vm, b); tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_ACK); - TCP_EVT_DBG (TCP_EVT_ACK_SENT, tc); - vnet_buffer (b)->tcp.flags = TCP_BUF_FLAG_ACK; + TCP_EVT (TCP_EVT_ACK_SENT, tc); tc->rcv_las = tc->rcv_nxt; } @@ -513,18 +568,33 @@ tcp_make_ack (tcp_connection_t * tc, vlib_buffer_t * b) void tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b) { - vlib_main_t *vm = vlib_get_main (); - u8 flags = 0; + tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK); +} - tcp_reuse_buffer (vm, b); +/** + * Convert buffer to SYN + */ +void +tcp_make_syn (tcp_connection_t * tc, vlib_buffer_t * b) +{ + u8 tcp_hdr_opts_len, tcp_opts_len; + tcp_header_t *th; + u16 initial_wnd; + tcp_options_t snd_opts; - flags = TCP_FLAG_FIN | TCP_FLAG_ACK; - tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, flags); + initial_wnd = tcp_initial_window_to_advertise (tc); - /* Reset flags, make sure ack is sent */ - vnet_buffer (b)->tcp.flags &= ~TCP_BUF_FLAG_DUPACK; + /* Make and write options */ + clib_memset (&snd_opts, 0, sizeof (snd_opts)); + tcp_opts_len = tcp_make_syn_options (tc, &snd_opts); + tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t); - tc->snd_nxt += 1; + th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss, + tc->rcv_nxt, tcp_hdr_opts_len, TCP_FLAG_SYN, + initial_wnd); + vnet_buffer (b)->tcp.connection_index = tc->c_c_index; + tcp_options_write ((u8 *) (th + 1), &snd_opts); + th->checksum = tcp_compute_checksum (tc, b); } /** @@ -533,181 +603,198 @@ tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b) void tcp_make_synack (tcp_connection_t * tc, vlib_buffer_t * b) { - vlib_main_t *vm = vlib_get_main (); tcp_options_t _snd_opts, *snd_opts = &_snd_opts; u8 tcp_opts_len, tcp_hdr_opts_len; tcp_header_t *th; u16 initial_wnd; - u32 time_now; - - memset (snd_opts, 0, sizeof (*snd_opts)); - - tcp_reuse_buffer (vm, b); - - /* Set random initial sequence */ - time_now = tcp_time_now (); - - tc->iss = random_u32 (&time_now); - tc->snd_una = tc->iss; - tc->snd_nxt = tc->iss + 1; - tc->snd_una_max = tc->snd_nxt; + clib_memset (snd_opts, 0, sizeof (*snd_opts)); initial_wnd = tcp_initial_window_to_advertise (tc); - - /* Make and write options */ tcp_opts_len = tcp_make_synack_options (tc, snd_opts); tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t); th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss, tc->rcv_nxt, tcp_hdr_opts_len, TCP_FLAG_SYN | TCP_FLAG_ACK, initial_wnd); - tcp_options_write ((u8 *) (th + 1), snd_opts); vnet_buffer (b)->tcp.connection_index = tc->c_c_index; - vnet_buffer (b)->tcp.flags = TCP_BUF_FLAG_ACK; - - /* Init retransmit timer */ - tcp_retransmit_timer_set (tc); + th->checksum = tcp_compute_checksum (tc, b); } always_inline void -tcp_enqueue_to_ip_lookup (vlib_main_t * vm, vlib_buffer_t * b, u32 bi, - u8 is_ip4) +tcp_enqueue_to_ip_lookup_i (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi, + u8 is_ip4, u32 fib_index, u8 flush) { + vlib_main_t *vm = wrk->vm; u32 *to_next, next_index; vlib_frame_t *f; - b->flags |= VNET_BUFFER_LOCALLY_ORIGINATED; + b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED; b->error = 0; - /* Default FIB for now */ - vnet_buffer (b)->sw_if_index[VLIB_TX] = 0; + vnet_buffer (b)->sw_if_index[VLIB_TX] = fib_index; + vnet_buffer (b)->sw_if_index[VLIB_RX] = 0; /* Send to IP lookup */ next_index = is_ip4 ? ip4_lookup_node.index : ip6_lookup_node.index; - f = vlib_get_frame_to_node (vm, next_index); + tcp_trajectory_add_start (b, 1); + + f = wrk->ip_lookup_tx_frames[!is_ip4]; + if (!f) + { + f = vlib_get_frame_to_node (vm, next_index); + ASSERT (f); + wrk->ip_lookup_tx_frames[!is_ip4] = f; + } - /* Enqueue the packet */ to_next = vlib_frame_vector_args (f); - to_next[0] = bi; - f->n_vectors = 1; - vlib_put_frame_to_node (vm, next_index, f); + to_next[f->n_vectors] = bi; + f->n_vectors += 1; + if (flush || f->n_vectors == VLIB_FRAME_SIZE) + { + vlib_put_frame_to_node (vm, next_index, f); + wrk->ip_lookup_tx_frames[!is_ip4] = 0; + } } -int -tcp_make_reset_in_place (vlib_main_t * vm, vlib_buffer_t * b0, - tcp_state_t state, u32 my_thread_index, u8 is_ip4) +static void +tcp_enqueue_to_ip_lookup_now (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, + u32 bi, u8 is_ip4, u32 fib_index) +{ + tcp_enqueue_to_ip_lookup_i (wrk, b, bi, is_ip4, fib_index, 1); +} + +static void +tcp_enqueue_to_ip_lookup (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi, + u8 is_ip4, u32 fib_index) +{ + tcp_enqueue_to_ip_lookup_i (wrk, b, bi, is_ip4, fib_index, 0); + if (wrk->vm->thread_index == 0 && vlib_num_workers ()) + session_flush_frames_main_thread (wrk->vm); +} + +static void +tcp_enqueue_to_output (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi, + u8 is_ip4) +{ + session_type_t st; + + b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED; + b->error = 0; + + st = session_type_from_proto_and_ip (TRANSPORT_PROTO_TCP, is_ip4); + session_add_pending_tx_buffer (st, wrk->vm->thread_index, bi); +} + +#endif /* CLIB_MARCH_VARIANT */ + +static int +tcp_make_reset_in_place (vlib_main_t * vm, vlib_buffer_t * b, u8 is_ip4) { - u8 tcp_hdr_len = sizeof (tcp_header_t); ip4_header_t *ih4; ip6_header_t *ih6; - tcp_header_t *th0; - ip4_address_t src_ip40; - ip6_address_t src_ip60; - u16 src_port0; - u32 tmp; + tcp_header_t *th; + ip4_address_t src_ip4, dst_ip4; + ip6_address_t src_ip6, dst_ip6; + u16 src_port, dst_port; + u32 tmp, len, seq, ack; + u8 flags; /* Find IP and TCP headers */ - if (is_ip4) - { - ih4 = vlib_buffer_get_current (b0); - th0 = ip4_next_header (ih4); - } - else - { - ih6 = vlib_buffer_get_current (b0); - th0 = ip6_next_header (ih6); - } + th = tcp_buffer_hdr (b); - /* Swap src and dst ip */ + /* Save src and dst ip */ if (is_ip4) { + ih4 = vlib_buffer_get_current (b); ASSERT ((ih4->ip_version_and_header_length & 0xF0) == 0x40); - src_ip40.as_u32 = ih4->src_address.as_u32; - ih4->src_address.as_u32 = ih4->dst_address.as_u32; - ih4->dst_address.as_u32 = src_ip40.as_u32; - - /* Chop the end of the pkt */ - b0->current_length += ip4_header_bytes (ih4) + tcp_hdr_len; + src_ip4.as_u32 = ih4->src_address.as_u32; + dst_ip4.as_u32 = ih4->dst_address.as_u32; } else { + ih6 = vlib_buffer_get_current (b); ASSERT ((ih6->ip_version_traffic_class_and_flow_label & 0xF0) == 0x60); - clib_memcpy (&src_ip60, &ih6->src_address, sizeof (ip6_address_t)); - clib_memcpy (&ih6->src_address, &ih6->dst_address, - sizeof (ip6_address_t)); - clib_memcpy (&ih6->dst_address, &src_ip60, sizeof (ip6_address_t)); - - /* Chop the end of the pkt */ - b0->current_length += sizeof (ip6_header_t) + tcp_hdr_len; + clib_memcpy_fast (&src_ip6, &ih6->src_address, sizeof (ip6_address_t)); + clib_memcpy_fast (&dst_ip6, &ih6->dst_address, sizeof (ip6_address_t)); } - /* Try to determine what/why we're actually resetting and swap - * src and dst ports */ - if (state == TCP_STATE_CLOSED) - { - if (!tcp_syn (th0)) - return -1; - - tmp = clib_net_to_host_u32 (th0->seq_number); - - /* Got a SYN for no listener. */ - th0->flags = TCP_FLAG_RST | TCP_FLAG_ACK; - th0->ack_number = clib_host_to_net_u32 (tmp + 1); - th0->seq_number = 0; + src_port = th->src_port; + dst_port = th->dst_port; + flags = TCP_FLAG_RST; + /* + * RFC 793. If the ACK bit is off, sequence number zero is used, + * + * If the ACK bit is on, + * + */ + if (tcp_ack (th)) + { + seq = th->ack_number; + ack = 0; } - else if (state >= TCP_STATE_SYN_SENT) + else { - th0->flags = TCP_FLAG_RST | TCP_FLAG_ACK; - th0->seq_number = th0->ack_number; - th0->ack_number = 0; + flags |= TCP_FLAG_ACK; + tmp = clib_net_to_host_u32 (th->seq_number); + len = vnet_buffer (b)->tcp.data_len + tcp_is_syn (th) + tcp_is_fin (th); + ack = clib_host_to_net_u32 (tmp + len); + seq = 0; } - src_port0 = th0->src_port; - th0->src_port = th0->dst_port; - th0->dst_port = src_port0; - th0->window = 0; - th0->data_offset_and_reserved = (tcp_hdr_len >> 2) << 4; - th0->urgent_pointer = 0; + tcp_reuse_buffer (vm, b); + tcp_trajectory_add_start (b, 4); + th = vlib_buffer_push_tcp_net_order (b, dst_port, src_port, seq, ack, + sizeof (tcp_header_t), flags, 0); - /* Compute checksum */ if (is_ip4) { - th0->checksum = ip4_tcp_udp_compute_checksum (vm, b0, ih4); + ih4 = vlib_buffer_push_ip4 (vm, b, &dst_ip4, &src_ip4, + IP_PROTOCOL_TCP, 1); + th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4); } else { int bogus = ~0; - th0->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b0, ih6, &bogus); + ih6 = vlib_buffer_push_ip6 (vm, b, &dst_ip6, &src_ip6, IP_PROTOCOL_TCP); + th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus); ASSERT (!bogus); } return 0; } +#ifndef CLIB_MARCH_VARIANT /** * Send reset without reusing existing buffer + * + * It extracts connection info out of original packet */ void -tcp_send_reset (vlib_buffer_t * pkt, u8 is_ip4) +tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt, + u32 thread_index, u8 is_ip4) { + tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index); + vlib_main_t *vm = wrk->vm; vlib_buffer_t *b; - u32 bi; - tcp_main_t *tm = vnet_get_tcp_main (); - vlib_main_t *vm = vlib_get_main (); + u32 bi, sw_if_index, fib_index; u8 tcp_hdr_len, flags = 0; tcp_header_t *th, *pkt_th; u32 seq, ack; ip4_header_t *ih4, *pkt_ih4; ip6_header_t *ih6, *pkt_ih6; + fib_protocol_t fib_proto; - tcp_get_free_buffer_index (tm, &bi); - b = vlib_get_buffer (vm, bi); + if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1))) + return; - /* Leave enough space for headers */ - vlib_buffer_make_headroom (b, MAX_HDRS_LEN); + b = vlib_get_buffer (vm, bi); + sw_if_index = vnet_buffer (pkt)->sw_if_index[VLIB_RX]; + fib_proto = is_ip4 ? FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6; + fib_index = fib_table_get_index_for_sw_if_index (fib_proto, sw_if_index); + tcp_init_buffer (vm, b); /* Make and write options */ tcp_hdr_len = sizeof (tcp_header_t); @@ -727,7 +814,7 @@ tcp_send_reset (vlib_buffer_t * pkt, u8 is_ip4) { flags = TCP_FLAG_RST; seq = pkt_th->ack_number; - ack = 0; + ack = (tc->state >= TCP_STATE_SYN_RCVD) ? tc->rcv_nxt : 0; } else { @@ -744,47 +831,78 @@ tcp_send_reset (vlib_buffer_t * pkt, u8 is_ip4) { ASSERT ((pkt_ih4->ip_version_and_header_length & 0xF0) == 0x40); ih4 = vlib_buffer_push_ip4 (vm, b, &pkt_ih4->dst_address, - &pkt_ih4->src_address, IP_PROTOCOL_TCP); + &pkt_ih4->src_address, IP_PROTOCOL_TCP, + tcp_csum_offload (tc)); th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4); } else { int bogus = ~0; - pkt_ih6 = (ip6_header_t *) (pkt_th - 1); ASSERT ((pkt_ih6->ip_version_traffic_class_and_flow_label & 0xF0) == 0x60); - ih6 = - vlib_buffer_push_ip6 (vm, b, &pkt_ih6->dst_address, - &pkt_ih6->src_address, IP_PROTOCOL_TCP); + ih6 = vlib_buffer_push_ip6_custom (vm, b, &pkt_ih6->dst_address, + &pkt_ih6->src_address, + IP_PROTOCOL_TCP, + tc->ipv6_flow_label); th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus); ASSERT (!bogus); } - tcp_enqueue_to_ip_lookup (vm, b, bi, is_ip4); + tcp_enqueue_to_ip_lookup_now (wrk, b, bi, is_ip4, fib_index); + TCP_EVT (TCP_EVT_RST_SENT, tc); + vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4), + TCP_ERROR_RST_SENT, 1); } +/** + * Build and set reset packet for connection + */ void -tcp_push_ip_hdr (tcp_main_t * tm, tcp_connection_t * tc, vlib_buffer_t * b) +tcp_send_reset (tcp_connection_t * tc) { - tcp_header_t *th = vlib_buffer_get_current (b); + tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index); + vlib_main_t *vm = wrk->vm; + vlib_buffer_t *b; + u32 bi; + tcp_header_t *th; + u16 tcp_hdr_opts_len, advertise_wnd, opts_write_len; + u8 flags; + + if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1))) + return; + b = vlib_get_buffer (vm, bi); + tcp_init_buffer (vm, b); + + tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state); + tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t); + advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED); + flags = TCP_FLAG_RST; + th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt, + tc->rcv_nxt, tcp_hdr_opts_len, flags, + advertise_wnd); + opts_write_len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts); + th->checksum = tcp_compute_checksum (tc, b); + ASSERT (opts_write_len == tc->snd_opts_len); + vnet_buffer (b)->tcp.connection_index = tc->c_c_index; + tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4); + TCP_EVT (TCP_EVT_RST_SENT, tc); + vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4), + TCP_ERROR_RST_SENT, 1); +} +static void +tcp_push_ip_hdr (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, + vlib_buffer_t * b) +{ if (tc->c_is_ip4) { - ip4_header_t *ih; - ih = vlib_buffer_push_ip4 (tm->vlib_main, b, &tc->c_lcl_ip4, - &tc->c_rmt_ip4, IP_PROTOCOL_TCP); - th->checksum = ip4_tcp_udp_compute_checksum (tm->vlib_main, b, ih); + vlib_buffer_push_ip4 (wrk->vm, b, &tc->c_lcl_ip4, &tc->c_rmt_ip4, + IP_PROTOCOL_TCP, tcp_csum_offload (tc)); } else { - ip6_header_t *ih; - int bogus = ~0; - - ih = vlib_buffer_push_ip6 (tm->vlib_main, b, &tc->c_lcl_ip6, - &tc->c_rmt_ip6, IP_PROTOCOL_TCP); - th->checksum = ip6_tcp_udp_icmp_compute_checksum (tm->vlib_main, b, ih, - &bogus); - ASSERT (!bogus); + vlib_buffer_push_ip6_custom (wrk->vm, b, &tc->c_lcl_ip6, &tc->c_rmt_ip6, + IP_PROTOCOL_TCP, tc->ipv6_flow_label); } } @@ -798,75 +916,60 @@ tcp_push_ip_hdr (tcp_main_t * tm, tcp_connection_t * tc, vlib_buffer_t * b) void tcp_send_syn (tcp_connection_t * tc) { + tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index); + vlib_main_t *vm = wrk->vm; vlib_buffer_t *b; u32 bi; - tcp_main_t *tm = vnet_get_tcp_main (); - vlib_main_t *vm = vlib_get_main (); - u8 tcp_hdr_opts_len, tcp_opts_len; - tcp_header_t *th; - u32 time_now; - u16 initial_wnd; - tcp_options_t snd_opts; - - tcp_get_free_buffer_index (tm, &bi); - b = vlib_get_buffer (vm, bi); - - /* Leave enough space for headers */ - vlib_buffer_make_headroom (b, MAX_HDRS_LEN); - - /* Set random initial sequence */ - time_now = tcp_time_now (); - tc->iss = random_u32 (&time_now); - tc->snd_una = tc->iss; - tc->snd_una_max = tc->snd_nxt = tc->iss + 1; - - initial_wnd = tcp_initial_window_to_advertise (tc); - - /* Make and write options */ - memset (&snd_opts, 0, sizeof (snd_opts)); - tcp_opts_len = tcp_make_syn_options (&snd_opts, tc->rcv_wscale); - tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t); + /* + * Setup retransmit and establish timers before requesting buffer + * such that we can return if we've ran out. + */ + tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN, + tc->rto * TCP_TO_TIMER_TICK); - th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss, - tc->rcv_nxt, tcp_hdr_opts_len, TCP_FLAG_SYN, - initial_wnd); + if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1))) + { + tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN, 1); + return; + } - tcp_options_write ((u8 *) (th + 1), &snd_opts); + b = vlib_get_buffer (vm, bi); + tcp_init_buffer (vm, b); + tcp_make_syn (tc, b); /* Measure RTT with this */ - tc->rtt_ts = tcp_time_now (); + tc->rtt_ts = tcp_time_now_us (vlib_num_workers ()? 1 : 0); tc->rtt_seq = tc->snd_nxt; - - /* Start retransmit trimer */ - tcp_timer_set (tc, TCP_TIMER_RETRANSMIT_SYN, tc->rto * TCP_TO_TIMER_TICK); tc->rto_boff = 0; - /* Set the connection establishment timer */ - tcp_timer_set (tc, TCP_TIMER_ESTABLISH, TCP_ESTABLISH_TIME); - - tcp_push_ip_hdr (tm, tc, b); - tcp_enqueue_to_ip_lookup (vm, b, bi, tc->c_is_ip4); + tcp_push_ip_hdr (wrk, tc, b); + tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index); + TCP_EVT (TCP_EVT_SYN_SENT, tc); } -always_inline void -tcp_enqueue_to_output (vlib_main_t * vm, vlib_buffer_t * b, u32 bi, u8 is_ip4) +void +tcp_send_synack (tcp_connection_t * tc) { - u32 *to_next, next_index; - vlib_frame_t *f; + tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index); + vlib_main_t *vm = wrk->vm; + vlib_buffer_t *b; + u32 bi; - b->flags |= VNET_BUFFER_LOCALLY_ORIGINATED; - b->error = 0; + tcp_retransmit_timer_force_update (tc); - /* Decide where to send the packet */ - next_index = is_ip4 ? tcp4_output_node.index : tcp6_output_node.index; + if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1))) + { + tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1); + return; + } - /* Enqueue the packet */ - f = vlib_get_frame_to_node (vm, next_index); - to_next = vlib_frame_vector_args (f); - to_next[0] = bi; - f->n_vectors = 1; - vlib_put_frame_to_node (vm, next_index, f); + tc->rtt_ts = tcp_time_now_us (tc->c_thread_index); + b = vlib_get_buffer (vm, bi); + tcp_init_buffer (vm, b); + tcp_make_synack (tc, b); + tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4); + TCP_EVT (TCP_EVT_SYNACK_SENT, tc); } /** @@ -875,619 +978,1448 @@ tcp_enqueue_to_output (vlib_main_t * vm, vlib_buffer_t * b, u32 bi, u8 is_ip4) void tcp_send_fin (tcp_connection_t * tc) { + tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index); + vlib_main_t *vm = wrk->vm; vlib_buffer_t *b; u32 bi; - tcp_main_t *tm = vnet_get_tcp_main (); - vlib_main_t *vm = vlib_get_main (); + u8 fin_snt = 0; - tcp_get_free_buffer_index (tm, &bi); - b = vlib_get_buffer (vm, bi); + fin_snt = tc->flags & TCP_CONN_FINSNT; + if (fin_snt) + tc->snd_nxt -= 1; - /* Leave enough space for headers */ - vlib_buffer_make_headroom (b, MAX_HDRS_LEN); + if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1))) + { + /* Out of buffers so program fin retransmit ASAP */ + tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1); + if (fin_snt) + tc->snd_nxt += 1; + else + /* Make sure retransmit retries a fin not data */ + tc->flags |= TCP_CONN_FINSNT; + return; + } - tcp_make_fin (tc, b); - tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4); - tc->flags |= TCP_CONN_FINSNT; - TCP_EVT_DBG (TCP_EVT_FIN_SENT, tc); -} + /* If we have non-dupacks programmed, no need to send them */ + if ((tc->flags & TCP_CONN_SNDACK) && !tc->pending_dupacks) + tc->flags &= ~TCP_CONN_SNDACK; -always_inline u8 -tcp_make_state_flags (tcp_state_t next_state) -{ - switch (next_state) + tcp_retransmit_timer_force_update (tc); + b = vlib_get_buffer (vm, bi); + tcp_init_buffer (vm, b); + tcp_make_fin (tc, b); + tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4); + TCP_EVT (TCP_EVT_FIN_SENT, tc); + /* Account for the FIN */ + tc->snd_nxt += 1; + if (!fin_snt) { - case TCP_STATE_ESTABLISHED: - return TCP_FLAG_ACK; - case TCP_STATE_SYN_RCVD: - return TCP_FLAG_SYN | TCP_FLAG_ACK; - case TCP_STATE_SYN_SENT: - return TCP_FLAG_SYN; - case TCP_STATE_LAST_ACK: - case TCP_STATE_FIN_WAIT_1: - return TCP_FLAG_FIN; - default: - clib_warning ("Shouldn't be here!"); + tc->flags |= TCP_CONN_FINSNT; + tc->flags &= ~TCP_CONN_FINPNDG; + tc->snd_una_max = seq_max (tc->snd_una_max, tc->snd_nxt); } - return 0; } /** - * Push TCP header and update connection variables + * Push TCP header and update connection variables. Should only be called + * for segments with data, not for 'control' packets. */ -static void -tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b, - tcp_state_t next_state, u8 compute_opts) +always_inline void +tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b, u32 snd_nxt, + u8 compute_opts, u8 maybe_burst, u8 update_snd_nxt) { + u8 tcp_hdr_opts_len, flags = TCP_FLAG_ACK; u32 advertise_wnd, data_len; - u8 tcp_hdr_opts_len, opts_write_len, flags; + tcp_main_t *tm = &tcp_main; tcp_header_t *th; - data_len = b->current_length + b->total_length_not_including_first_buffer; + data_len = b->current_length; + if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT)) + data_len += b->total_length_not_including_first_buffer; + vnet_buffer (b)->tcp.flags = 0; + vnet_buffer (b)->tcp.connection_index = tc->c_c_index; if (compute_opts) tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state); - /* Write pre-computed options */ tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t); - /* Get rcv window to advertise */ - advertise_wnd = tcp_window_to_advertise (tc, next_state); - flags = tcp_make_state_flags (next_state); + if (maybe_burst) + advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale; + else + advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED); - /* Push header and options */ - th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt, + if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING)) + { + if (seq_geq (tc->psh_seq, snd_nxt) + && seq_lt (tc->psh_seq, snd_nxt + data_len)) + flags |= TCP_FLAG_PSH; + } + th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, snd_nxt, tc->rcv_nxt, tcp_hdr_opts_len, flags, advertise_wnd); - opts_write_len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts); - - ASSERT (opts_write_len == tc->snd_opts_len); + if (maybe_burst) + { + clib_memcpy_fast ((u8 *) (th + 1), + tm->wrk_ctx[tc->c_thread_index].cached_opts, + tc->snd_opts_len); + } + else + { + u8 len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts); + ASSERT (len == tc->snd_opts_len); + } - /* Tag the buffer with the connection index */ - vnet_buffer (b)->tcp.connection_index = tc->c_c_index; + /* + * Update connection variables + */ - tc->snd_nxt += data_len; + if (update_snd_nxt) + tc->snd_nxt += data_len; tc->rcv_las = tc->rcv_nxt; - /* TODO this is updated in output as well ... */ - if (tc->snd_nxt > tc->snd_una_max) - tc->snd_una_max = tc->snd_nxt; + tc->bytes_out += data_len; + tc->data_segs_out += 1; + + th->checksum = tcp_compute_checksum (tc, b); + + TCP_EVT (TCP_EVT_PKTIZE, tc); +} + +always_inline u32 +tcp_buffer_len (vlib_buffer_t * b) +{ + u32 data_len = b->current_length; + if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT)) + data_len += b->total_length_not_including_first_buffer; + return data_len; +} + +u32 +tcp_session_push_header (transport_connection_t * tconn, vlib_buffer_t * b) +{ + tcp_connection_t *tc = (tcp_connection_t *) tconn; + + if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE) + tcp_bt_track_tx (tc, tcp_buffer_len (b)); + + tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0, /* burst */ 1, + /* update_snd_nxt */ 1); - if (tc->rtt_ts == 0) + tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max); + tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una); + /* If not tracking an ACK, start tracking */ + if (tc->rtt_ts == 0 && !tcp_in_cong_recovery (tc)) { - tc->rtt_ts = tcp_time_now (); + tc->rtt_ts = tcp_time_now_us (tc->c_thread_index); tc->rtt_seq = tc->snd_nxt; } - TCP_EVT_DBG (TCP_EVT_PKTIZE, tc); + if (PREDICT_FALSE (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))) + { + tcp_retransmit_timer_set (tc); + tc->rto_boff = 0; + } + tcp_trajectory_add_start (b, 3); + return 0; } void tcp_send_ack (tcp_connection_t * tc) { - tcp_main_t *tm = vnet_get_tcp_main (); - vlib_main_t *vm = vlib_get_main (); - + tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index); + vlib_main_t *vm = wrk->vm; vlib_buffer_t *b; u32 bi; - /* Get buffer */ - tcp_get_free_buffer_index (tm, &bi); + if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1))) + { + tcp_update_rcv_wnd (tc); + return; + } b = vlib_get_buffer (vm, bi); - - /* Fill in the ACK */ + tcp_init_buffer (vm, b); tcp_make_ack (tc, b); - tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4); + tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4); } -/* Send delayed ACK when timer expires */ void -tcp_timer_delack_handler (u32 index) +tcp_program_ack (tcp_connection_t * tc) { - u32 thread_index = vlib_get_thread_index (); - tcp_connection_t *tc; + if (!(tc->flags & TCP_CONN_SNDACK)) + { + session_add_self_custom_tx_evt (&tc->connection, 1); + tc->flags |= TCP_CONN_SNDACK; + } +} + +void +tcp_program_dupack (tcp_connection_t * tc) +{ + if (!(tc->flags & TCP_CONN_SNDACK)) + { + session_add_self_custom_tx_evt (&tc->connection, 1); + tc->flags |= TCP_CONN_SNDACK; + } + if (tc->pending_dupacks < 255) + tc->pending_dupacks += 1; +} - tc = tcp_connection_get (index, thread_index); - tc->timers[TCP_TIMER_DELACK] = TCP_TIMER_HANDLE_INVALID; +void +tcp_program_retransmit (tcp_connection_t * tc) +{ + if (!(tc->flags & TCP_CONN_RXT_PENDING)) + { + session_add_self_custom_tx_evt (&tc->connection, 0); + tc->flags |= TCP_CONN_RXT_PENDING; + } +} + +/** + * Delayed ack timer handler + * + * Sends delayed ACK when timer expires + */ +void +tcp_timer_delack_handler (tcp_connection_t * tc) +{ tcp_send_ack (tc); } -/** Build a retransmit segment +/** + * Send window update ack + * + * Ensures that it will be sent only once, after a zero rwnd has been + * advertised in a previous ack, and only if rwnd has grown beyond a + * configurable value. + */ +void +tcp_send_window_update_ack (tcp_connection_t * tc) +{ + if (tcp_zero_rwnd_sent (tc)) + { + tcp_update_rcv_wnd (tc); + if (tc->rcv_wnd >= tcp_cfg.rwnd_min_update_ack * tc->snd_mss) + { + tcp_zero_rwnd_sent_off (tc); + tcp_program_ack (tc); + } + } +} + +/** + * Allocate a new buffer and build a new tcp segment + * + * @param wrk tcp worker + * @param tc connection for which the segment will be allocated + * @param offset offset of the first byte in the tx fifo + * @param max_deq_byte segment size + * @param[out] b pointer to buffer allocated + * + * @return the number of bytes in the segment or 0 if buffer cannot be + * allocated or no data available + */ +static int +tcp_prepare_segment (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, + u32 offset, u32 max_deq_bytes, vlib_buffer_t ** b) +{ + u32 bytes_per_buffer = vnet_get_tcp_main ()->bytes_per_buffer; + vlib_main_t *vm = wrk->vm; + u32 bi, seg_size; + int n_bytes = 0; + u8 *data; + + seg_size = max_deq_bytes + TRANSPORT_MAX_HDRS_LEN; + + /* + * Prepare options + */ + tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state); + + /* + * Allocate and fill in buffer(s) + */ + + /* Easy case, buffer size greater than mss */ + if (PREDICT_TRUE (seg_size <= bytes_per_buffer)) + { + if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1))) + return 0; + *b = vlib_get_buffer (vm, bi); + data = tcp_init_buffer (vm, *b); + n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset, + max_deq_bytes); + ASSERT (n_bytes == max_deq_bytes); + b[0]->current_length = n_bytes; + tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0, + /* burst */ 0, /* update_snd_nxt */ 0); + } + /* Split mss into multiple buffers */ + else + { + u32 chain_bi = ~0, n_bufs_per_seg, n_bufs; + u16 n_peeked, len_to_deq; + vlib_buffer_t *chain_b, *prev_b; + int i; + + /* Make sure we have enough buffers */ + n_bufs_per_seg = ceil ((double) seg_size / bytes_per_buffer); + vec_validate_aligned (wrk->tx_buffers, n_bufs_per_seg - 1, + CLIB_CACHE_LINE_BYTES); + n_bufs = vlib_buffer_alloc (vm, wrk->tx_buffers, n_bufs_per_seg); + if (PREDICT_FALSE (n_bufs != n_bufs_per_seg)) + { + if (n_bufs) + vlib_buffer_free (vm, wrk->tx_buffers, n_bufs); + return 0; + } + + *b = vlib_get_buffer (vm, wrk->tx_buffers[--n_bufs]); + data = tcp_init_buffer (vm, *b); + n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset, + bytes_per_buffer - + TRANSPORT_MAX_HDRS_LEN); + b[0]->current_length = n_bytes; + b[0]->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID; + b[0]->total_length_not_including_first_buffer = 0; + max_deq_bytes -= n_bytes; + + chain_b = *b; + for (i = 1; i < n_bufs_per_seg; i++) + { + prev_b = chain_b; + len_to_deq = clib_min (max_deq_bytes, bytes_per_buffer); + chain_bi = wrk->tx_buffers[--n_bufs]; + chain_b = vlib_get_buffer (vm, chain_bi); + chain_b->current_data = 0; + data = vlib_buffer_get_current (chain_b); + n_peeked = session_tx_fifo_peek_bytes (&tc->connection, data, + offset + n_bytes, + len_to_deq); + ASSERT (n_peeked == len_to_deq); + n_bytes += n_peeked; + chain_b->current_length = n_peeked; + chain_b->next_buffer = 0; + + /* update previous buffer */ + prev_b->next_buffer = chain_bi; + prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT; + + max_deq_bytes -= n_peeked; + b[0]->total_length_not_including_first_buffer += n_peeked; + } + + tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0, + /* burst */ 0, /* update_snd_nxt */ 0); + + if (PREDICT_FALSE (n_bufs)) + { + clib_warning ("not all buffers consumed"); + vlib_buffer_free (vm, wrk->tx_buffers, n_bufs); + } + } + + ASSERT (n_bytes > 0); + ASSERT (((*b)->current_data + (*b)->current_length) <= bytes_per_buffer); + + return n_bytes; +} + +/** + * Build a retransmit segment * * @return the number of bytes in the segment or 0 if there's nothing to * retransmit - * */ -u32 -tcp_prepare_retransmit_segment (tcp_connection_t * tc, vlib_buffer_t * b, - u32 offset, u32 max_bytes) + */ +static u32 +tcp_prepare_retransmit_segment (tcp_worker_ctx_t * wrk, + tcp_connection_t * tc, u32 offset, + u32 max_deq_bytes, vlib_buffer_t ** b) { - vlib_main_t *vm = vlib_get_main (); - u32 n_bytes = 0; + u32 start, available_bytes; + int n_bytes = 0; - tcp_reuse_buffer (vm, b); + ASSERT (tc->state >= TCP_STATE_ESTABLISHED); + ASSERT (max_deq_bytes != 0); + + /* + * Make sure we can retransmit something + */ + available_bytes = transport_max_tx_dequeue (&tc->connection); + ASSERT (available_bytes >= offset); + available_bytes -= offset; + if (!available_bytes) + return 0; + + max_deq_bytes = clib_min (tc->snd_mss, max_deq_bytes); + max_deq_bytes = clib_min (available_bytes, max_deq_bytes); + + start = tc->snd_una + offset; + ASSERT (seq_leq (start + max_deq_bytes, tc->snd_nxt)); + + n_bytes = tcp_prepare_segment (wrk, tc, offset, max_deq_bytes, b); + if (!n_bytes) + return 0; + + tc->snd_rxt_bytes += n_bytes; + + if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE) + tcp_bt_track_rxt (tc, start, start + n_bytes); + + tc->bytes_retrans += n_bytes; + tc->segs_retrans += 1; + tcp_workerp_stats_inc (wrk, rxt_segs, 1); + TCP_EVT (TCP_EVT_CC_RTX, tc, offset, n_bytes); + + return n_bytes; +} + +static void +tcp_check_sack_reneging (tcp_connection_t * tc) +{ + sack_scoreboard_t *sb = &tc->sack_sb; + sack_scoreboard_hole_t *hole; + + hole = scoreboard_first_hole (sb); + if (!sb->is_reneging && (!hole || hole->start == tc->snd_una)) + return; + + scoreboard_clear_reneging (sb, tc->snd_una, tc->snd_nxt); +} + +/** + * Reset congestion control, switch cwnd to loss window and try again. + */ +static void +tcp_cc_init_rxt_timeout (tcp_connection_t * tc) +{ + TCP_EVT (TCP_EVT_CC_EVT, tc, 6); + + tc->prev_ssthresh = tc->ssthresh; + tc->prev_cwnd = tc->cwnd; + + /* If we entrered loss without fast recovery, notify cc algo of the + * congestion event such that it can update ssthresh and its state */ + if (!tcp_in_fastrecovery (tc)) + tcp_cc_congestion (tc); + + /* Let cc algo decide loss cwnd and ssthresh post unrecovered loss */ + tcp_cc_loss (tc); + + tc->rtt_ts = 0; + tc->cwnd_acc_bytes = 0; + tc->tr_occurences += 1; + tcp_recovery_on (tc); +} + +void +tcp_timer_retransmit_handler (tcp_connection_t * tc) +{ + tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index); + vlib_main_t *vm = wrk->vm; + vlib_buffer_t *b = 0; + u32 bi, n_bytes; + + tcp_workerp_stats_inc (wrk, tr_events, 1); + + /* Should be handled by a different handler */ + if (PREDICT_FALSE (tc->state == TCP_STATE_SYN_SENT)) + return; + + /* Wait-close and retransmit could pop at the same time */ + if (tc->state == TCP_STATE_CLOSED) + return; + + if (tc->state >= TCP_STATE_ESTABLISHED) + { + TCP_EVT (TCP_EVT_CC_EVT, tc, 2); + + /* Lost FIN, retransmit and return */ + if (tc->flags & TCP_CONN_FINSNT) + { + tcp_send_fin (tc); + tc->rto_boff += 1; + tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX); + return; + } + + /* Shouldn't be here. This condition is tricky because it has to take + * into account boff > 0 due to persist timeout. */ + if ((tc->rto_boff == 0 && tc->snd_una == tc->snd_nxt) + || (tc->rto_boff > 0 && seq_geq (tc->snd_una, tc->snd_congestion) + && !tcp_flight_size (tc))) + { + ASSERT (!tcp_in_recovery (tc)); + tc->rto_boff = 0; + return; + } + + /* We're not in recovery so make sure rto_boff is 0. Can be non 0 due + * to persist timer timeout */ + if (!tcp_in_recovery (tc) && tc->rto_boff > 0) + { + tc->rto_boff = 0; + tcp_update_rto (tc); + } + + /* Peer is dead or network connectivity is lost. Close connection. + * RFC 1122 section 4.2.3.5 recommends a value of at least 100s. For + * a min rto of 0.2s we need to retry about 8 times. */ + if (tc->rto_boff >= TCP_RTO_BOFF_MAX) + { + tcp_send_reset (tc); + tcp_connection_set_state (tc, TCP_STATE_CLOSED); + session_transport_closing_notify (&tc->connection); + session_transport_closed_notify (&tc->connection); + tcp_connection_timers_reset (tc); + tcp_program_cleanup (wrk, tc); + tcp_workerp_stats_inc (wrk, tr_abort, 1); + return; + } + + if (tcp_opts_sack_permitted (&tc->rcv_opts)) + tcp_check_sack_reneging (tc); + + /* Update send congestion to make sure that rxt has data to send */ + tc->snd_congestion = tc->snd_nxt; + + /* Send the first unacked segment. If we're short on buffers, return + * as soon as possible */ + n_bytes = clib_min (tc->snd_mss, tc->snd_nxt - tc->snd_una); + n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, n_bytes, &b); + if (!n_bytes) + { + tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1); + return; + } + + bi = vlib_get_buffer_index (vm, b); + tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4); + + tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX); + tcp_retransmit_timer_force_update (tc); + + tc->rto_boff += 1; + if (tc->rto_boff == 1) + { + tcp_cc_init_rxt_timeout (tc); + /* Record timestamp. Eifel detection algorithm RFC3522 */ + tc->snd_rxt_ts = tcp_tstamp (tc); + } + + if (tcp_opts_sack_permitted (&tc->rcv_opts)) + scoreboard_init_rxt (&tc->sack_sb, tc->snd_una + n_bytes); + + tcp_program_retransmit (tc); + } + /* Retransmit SYN-ACK */ + else if (tc->state == TCP_STATE_SYN_RCVD) + { + TCP_EVT (TCP_EVT_CC_EVT, tc, 2); + + tc->rtt_ts = 0; + + /* Passive open establish timeout */ + if (tc->rto > TCP_ESTABLISH_TIME >> 1) + { + tcp_connection_set_state (tc, TCP_STATE_CLOSED); + tcp_connection_timers_reset (tc); + tcp_program_cleanup (wrk, tc); + tcp_workerp_stats_inc (wrk, tr_abort, 1); + return; + } + + if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1))) + { + tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1); + return; + } + + tc->rto_boff += 1; + if (tc->rto_boff > TCP_RTO_SYN_RETRIES) + tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX); + + tcp_retransmit_timer_force_update (tc); + + b = vlib_get_buffer (vm, bi); + tcp_init_buffer (vm, b); + tcp_make_synack (tc, b); + TCP_EVT (TCP_EVT_SYN_RXT, tc, 1); + + /* Retransmit timer already updated, just enqueue to output */ + tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4); + } + else + { + ASSERT (tc->state == TCP_STATE_CLOSED); + return; + } +} + +/** + * SYN retransmit timer handler. Active open only. + */ +void +tcp_timer_retransmit_syn_handler (tcp_connection_t * tc) +{ + tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index); + vlib_main_t *vm = wrk->vm; + vlib_buffer_t *b = 0; + u32 bi; + + /* Note: the connection may have transitioned to ESTABLISHED... */ + if (PREDICT_FALSE (tc->state != TCP_STATE_SYN_SENT)) + return; + + /* Half-open connection actually moved to established but we were + * waiting for syn retransmit to pop to call cleanup from the right + * thread. */ + if (tc->flags & TCP_CONN_HALF_OPEN_DONE) + { + if (tcp_half_open_connection_cleanup (tc)) + TCP_DBG ("could not remove half-open connection"); + return; + } + + TCP_EVT (TCP_EVT_CC_EVT, tc, 2); + tc->rtt_ts = 0; + + /* Active open establish timeout */ + if (tc->rto >= TCP_ESTABLISH_TIME >> 1) + { + session_stream_connect_notify (&tc->connection, 1 /* fail */ ); + tcp_connection_cleanup (tc); + return; + } + + if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1))) + { + tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN, 1); + return; + } + + /* Try without increasing RTO a number of times. If this fails, + * start growing RTO exponentially */ + tc->rto_boff += 1; + if (tc->rto_boff > TCP_RTO_SYN_RETRIES) + tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX); + + b = vlib_get_buffer (vm, bi); + tcp_init_buffer (vm, b); + tcp_make_syn (tc, b); + + TCP_EVT (TCP_EVT_SYN_RXT, tc, 0); + + /* This goes straight to ipx_lookup */ + tcp_push_ip_hdr (wrk, tc, b); + tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index); + + tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN, + tc->rto * TCP_TO_TIMER_TICK); +} + +/** + * Got 0 snd_wnd from peer, try to do something about it. + * + */ +void +tcp_timer_persist_handler (tcp_connection_t * tc) +{ + tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index); + u32 bi, max_snd_bytes, available_bytes, offset; + tcp_main_t *tm = vnet_get_tcp_main (); + vlib_main_t *vm = wrk->vm; + vlib_buffer_t *b; + int n_bytes = 0; + u8 *data; + + /* Problem already solved or worse */ + if (tc->state == TCP_STATE_CLOSED || tc->snd_wnd > tc->snd_mss + || (tc->flags & TCP_CONN_FINSNT)) + goto update_scheduler; + + available_bytes = transport_max_tx_dequeue (&tc->connection); + offset = tc->snd_nxt - tc->snd_una; + + /* Reprogram persist if no new bytes available to send. We may have data + * next time */ + if (!available_bytes) + { + tcp_persist_timer_set (tc); + return; + } + + if (available_bytes <= offset) + goto update_scheduler; + + /* Increment RTO backoff */ + tc->rto_boff += 1; + tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX); + + /* + * Try to force the first unsent segment (or buffer) + */ + if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1))) + { + tcp_persist_timer_set (tc); + return; + } + + b = vlib_get_buffer (vm, bi); + data = tcp_init_buffer (vm, b); + + tcp_validate_txf_size (tc, offset); + tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state); + max_snd_bytes = clib_min (tc->snd_mss, + tm->bytes_per_buffer - TRANSPORT_MAX_HDRS_LEN); + n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset, + max_snd_bytes); + b->current_length = n_bytes; + ASSERT (n_bytes != 0 && (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT) + || tc->snd_nxt == tc->snd_una_max + || tc->rto_boff > 1)); + + if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE) + { + tcp_bt_check_app_limited (tc); + tcp_bt_track_tx (tc, n_bytes); + } + + tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0, + /* burst */ 0, /* update_snd_nxt */ 1); + tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max); + tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una); + tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4); + + /* Just sent new data, enable retransmit */ + tcp_retransmit_timer_update (tc); + + return; + +update_scheduler: + + if (tcp_is_descheduled (tc)) + transport_connection_reschedule (&tc->connection); +} + +/** + * Retransmit first unacked segment + */ +int +tcp_retransmit_first_unacked (tcp_worker_ctx_t * wrk, tcp_connection_t * tc) +{ + vlib_main_t *vm = wrk->vm; + vlib_buffer_t *b; + u32 bi, n_bytes; + + TCP_EVT (TCP_EVT_CC_EVT, tc, 1); + + n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, tc->snd_mss, &b); + if (!n_bytes) + return -1; + + bi = vlib_get_buffer_index (vm, b); + tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4); + + return 0; +} + +static int +tcp_transmit_unsent (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, + u32 burst_size) +{ + u32 offset, n_segs = 0, n_written, bi, available_wnd; + vlib_main_t *vm = wrk->vm; + vlib_buffer_t *b = 0; + + offset = tc->snd_nxt - tc->snd_una; + available_wnd = tc->snd_wnd - offset; + burst_size = clib_min (burst_size, available_wnd / tc->snd_mss); + + if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE) + tcp_bt_check_app_limited (tc); + + while (n_segs < burst_size) + { + n_written = tcp_prepare_segment (wrk, tc, offset, tc->snd_mss, &b); + if (!n_written) + goto done; + + bi = vlib_get_buffer_index (vm, b); + tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4); + offset += n_written; + n_segs += 1; + + if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE) + tcp_bt_track_tx (tc, n_written); + + tc->snd_nxt += n_written; + tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max); + } + +done: + return n_segs; +} + +/** + * Estimate send space using proportional rate reduction (RFC6937) + */ +int +tcp_fastrecovery_prr_snd_space (tcp_connection_t * tc) +{ + u32 pipe, prr_out; + int space; + + pipe = tcp_flight_size (tc); + prr_out = tc->snd_rxt_bytes + (tc->snd_nxt - tc->snd_congestion); + + if (pipe > tc->ssthresh) + { + space = ((int) tc->prr_delivered * ((f64) tc->ssthresh / tc->prev_cwnd)) + - prr_out; + } + else + { + int limit; + limit = clib_max ((int) (tc->prr_delivered - prr_out), 0) + tc->snd_mss; + space = clib_min (tc->ssthresh - pipe, limit); + } + space = clib_max (space, prr_out ? 0 : tc->snd_mss); + return space; +} + +static inline u8 +tcp_retransmit_should_retry_head (tcp_connection_t * tc, + sack_scoreboard_t * sb) +{ + u32 tx_adv_sack = sb->high_sacked - tc->snd_congestion; + f64 rr = (f64) tc->ssthresh / tc->prev_cwnd; + + if (tcp_fastrecovery_first (tc)) + return 1; + + return (tx_adv_sack > (tc->snd_una - tc->prr_start) * rr); +} + +static inline u8 +tcp_max_tx_deq (tcp_connection_t * tc) +{ + return (transport_max_tx_dequeue (&tc->connection) + - (tc->snd_nxt - tc->snd_una)); +} + +#define scoreboard_rescue_rxt_valid(_sb, _tc) \ + (seq_geq (_sb->rescue_rxt, _tc->snd_una) \ + && seq_leq (_sb->rescue_rxt, _tc->snd_congestion)) + +/** + * Do retransmit with SACKs + */ +static int +tcp_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, + u32 burst_size) +{ + u32 n_written = 0, offset, max_bytes, n_segs = 0; + u8 snd_limited = 0, can_rescue = 0; + u32 bi, max_deq, burst_bytes; + sack_scoreboard_hole_t *hole; + vlib_main_t *vm = wrk->vm; + vlib_buffer_t *b = 0; + sack_scoreboard_t *sb; + int snd_space; + + ASSERT (tcp_in_cong_recovery (tc)); + + burst_bytes = transport_connection_tx_pacer_burst (&tc->connection); + burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss); + if (!burst_size) + { + tcp_program_retransmit (tc); + return 0; + } + + if (tcp_in_recovery (tc)) + snd_space = tcp_available_cc_snd_space (tc); + else + snd_space = tcp_fastrecovery_prr_snd_space (tc); + + if (snd_space < tc->snd_mss) + goto done; + + sb = &tc->sack_sb; + + /* Check if snd_una is a lost retransmit */ + if (pool_elts (sb->holes) + && seq_gt (sb->high_sacked, tc->snd_congestion) + && tc->rxt_head != tc->snd_una + && tcp_retransmit_should_retry_head (tc, sb)) + { + max_bytes = clib_min (tc->snd_mss, tc->snd_congestion - tc->snd_una); + n_written = tcp_prepare_retransmit_segment (wrk, tc, 0, max_bytes, &b); + if (!n_written) + { + tcp_program_retransmit (tc); + goto done; + } + bi = vlib_get_buffer_index (vm, b); + tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4); + n_segs = 1; + + tc->rxt_head = tc->snd_una; + tc->rxt_delivered += n_written; + tc->prr_delivered += n_written; + ASSERT (tc->rxt_delivered <= tc->snd_rxt_bytes); + } + + tcp_fastrecovery_first_off (tc); + + TCP_EVT (TCP_EVT_CC_EVT, tc, 0); + hole = scoreboard_get_hole (sb, sb->cur_rxt_hole); + + max_deq = transport_max_tx_dequeue (&tc->connection); + max_deq -= tc->snd_nxt - tc->snd_una; + + while (snd_space > 0 && n_segs < burst_size) + { + hole = scoreboard_next_rxt_hole (sb, hole, max_deq != 0, &can_rescue, + &snd_limited); + if (!hole) + { + /* We are out of lost holes to retransmit so send some new data. */ + if (max_deq > tc->snd_mss) + { + u32 n_segs_new; + int av_wnd; + + /* Make sure we don't exceed available window and leave space + * for one more packet, to avoid zero window acks */ + av_wnd = (int) tc->snd_wnd - (tc->snd_nxt - tc->snd_una); + av_wnd = clib_max (av_wnd - tc->snd_mss, 0); + snd_space = clib_min (snd_space, av_wnd); + snd_space = clib_min (max_deq, snd_space); + burst_size = clib_min (burst_size - n_segs, + snd_space / tc->snd_mss); + burst_size = clib_min (burst_size, TCP_RXT_MAX_BURST); + n_segs_new = tcp_transmit_unsent (wrk, tc, burst_size); + if (max_deq > n_segs_new * tc->snd_mss) + tcp_program_retransmit (tc); + + n_segs += n_segs_new; + goto done; + } + + if (tcp_in_recovery (tc) || !can_rescue + || scoreboard_rescue_rxt_valid (sb, tc)) + break; + + /* If rescue rxt undefined or less than snd_una then one segment of + * up to SMSS octets that MUST include the highest outstanding + * unSACKed sequence number SHOULD be returned, and RescueRxt set to + * RecoveryPoint. HighRxt MUST NOT be updated. + */ + hole = scoreboard_last_hole (sb); + max_bytes = clib_min (tc->snd_mss, hole->end - hole->start); + max_bytes = clib_min (max_bytes, snd_space); + offset = hole->end - tc->snd_una - max_bytes; + n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, + max_bytes, &b); + if (!n_written) + goto done; + + sb->rescue_rxt = tc->snd_congestion; + bi = vlib_get_buffer_index (vm, b); + tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4); + n_segs += 1; + break; + } - ASSERT (tc->state >= TCP_STATE_ESTABLISHED); - ASSERT (max_bytes != 0); + max_bytes = clib_min (hole->end - sb->high_rxt, snd_space); + max_bytes = snd_limited ? clib_min (max_bytes, tc->snd_mss) : max_bytes; + if (max_bytes == 0) + break; - max_bytes = clib_min (tc->snd_mss, max_bytes); + offset = sb->high_rxt - tc->snd_una; + n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes, + &b); + ASSERT (n_written <= snd_space); - /* Start is beyond snd_congestion */ - if (seq_geq (tc->snd_una + offset, tc->snd_congestion)) - goto done; + /* Nothing left to retransmit */ + if (n_written == 0) + break; - /* Don't overshoot snd_congestion */ - if (seq_gt (tc->snd_nxt + max_bytes, tc->snd_congestion)) - { - max_bytes = tc->snd_congestion - tc->snd_nxt; - if (max_bytes == 0) - goto done; - } + bi = vlib_get_buffer_index (vm, b); + tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4); - tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state); + sb->high_rxt += n_written; + ASSERT (seq_leq (sb->high_rxt, tc->snd_nxt)); - ASSERT (max_bytes <= tc->snd_mss); + snd_space -= n_written; + n_segs += 1; + } - n_bytes = stream_session_peek_bytes (&tc->connection, - vlib_buffer_get_current (b), offset, - max_bytes); - ASSERT (n_bytes != 0); - b->current_length = n_bytes; - tcp_push_hdr_i (tc, b, tc->state, 0); - tc->rtx_bytes += n_bytes; + if (hole) + tcp_program_retransmit (tc); done: - TCP_EVT_DBG (TCP_EVT_CC_RTX, tc, offset, n_bytes); - return n_bytes; + + transport_connection_tx_pacer_reset_bucket (&tc->connection, 0); + return n_segs; } /** - * Reset congestion control, switch cwnd to loss window and try again. + * Fast retransmit without SACK info */ -static void -tcp_rtx_timeout_cc (tcp_connection_t * tc) +static int +tcp_retransmit_no_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, + u32 burst_size) { - /* Cleanly recover cc (also clears up fast retransmit) */ - if (tcp_in_fastrecovery (tc)) - { - tcp_cc_recover (tc); - } - else + u32 n_written = 0, offset = 0, bi, max_deq, n_segs_now, max_bytes; + u32 burst_bytes, sent_bytes; + vlib_main_t *vm = wrk->vm; + int snd_space, n_segs = 0; + u8 cc_limited = 0; + vlib_buffer_t *b; + + ASSERT (tcp_in_cong_recovery (tc)); + TCP_EVT (TCP_EVT_CC_EVT, tc, 0); + + burst_bytes = transport_connection_tx_pacer_burst (&tc->connection); + burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss); + if (!burst_size) { - tc->ssthresh = clib_max (tcp_flight_size (tc) / 2, 2 * tc->snd_mss); + tcp_program_retransmit (tc); + return 0; } - /* Start again from the beginning */ + snd_space = tcp_available_cc_snd_space (tc); + cc_limited = snd_space < burst_bytes; - tc->cwnd = tcp_loss_wnd (tc); - tc->snd_congestion = tc->snd_una_max; - tcp_recovery_on (tc); -} - -static void -tcp_timer_retransmit_handler_i (u32 index, u8 is_syn) -{ - tcp_main_t *tm = vnet_get_tcp_main (); - vlib_main_t *vm = vlib_get_main (); - u32 thread_index = vlib_get_thread_index (); - tcp_connection_t *tc; - vlib_buffer_t *b; - u32 bi, n_bytes; + if (!tcp_fastrecovery_first (tc)) + goto send_unsent; - if (is_syn) - { - tc = tcp_half_open_connection_get (index); - } - else + /* RFC 6582: [If a partial ack], retransmit the first unacknowledged + * segment. */ + while (snd_space > 0 && n_segs < burst_size) { - tc = tcp_connection_get (index, thread_index); - } + max_bytes = clib_min (tc->snd_mss, + tc->snd_congestion - tc->snd_una - offset); + if (!max_bytes) + break; + n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes, + &b); - /* Make sure timer handle is set to invalid */ - tc->timers[TCP_TIMER_RETRANSMIT] = TCP_TIMER_HANDLE_INVALID; + /* Nothing left to retransmit */ + if (n_written == 0) + break; - /* Increment RTO backoff (also equal to number of retries) */ - tc->rto_boff += 1; + bi = vlib_get_buffer_index (vm, b); + tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4); + snd_space -= n_written; + offset += n_written; + n_segs += 1; + } - /* Go back to first un-acked byte */ - tc->snd_nxt = tc->snd_una; + if (n_segs == burst_size) + goto done; - /* Get buffer */ - tcp_get_free_buffer_index (tm, &bi); - b = vlib_get_buffer (vm, bi); +send_unsent: - if (tc->state >= TCP_STATE_ESTABLISHED) + /* RFC 6582: Send a new segment if permitted by the new value of cwnd. */ + if (snd_space < tc->snd_mss || tc->snd_mss == 0) + goto done; + + max_deq = transport_max_tx_dequeue (&tc->connection); + max_deq -= tc->snd_nxt - tc->snd_una; + if (max_deq) { - /* First retransmit timeout */ - if (tc->rto_boff == 1) - tcp_rtx_timeout_cc (tc); + snd_space = clib_min (max_deq, snd_space); + burst_size = clib_min (burst_size - n_segs, snd_space / tc->snd_mss); + n_segs_now = tcp_transmit_unsent (wrk, tc, burst_size); + if (n_segs_now && max_deq > n_segs_now * tc->snd_mss) + tcp_program_retransmit (tc); + n_segs += n_segs_now; + } - /* Exponential backoff */ - tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX); +done: + tcp_fastrecovery_first_off (tc); + + sent_bytes = clib_min (n_segs * tc->snd_mss, burst_bytes); + sent_bytes = cc_limited ? burst_bytes : sent_bytes; + transport_connection_tx_pacer_update_bytes (&tc->connection, sent_bytes); - TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 1); + return n_segs; +} - /* Send one segment. No fancy recovery for now! */ - n_bytes = tcp_prepare_retransmit_segment (tc, b, 0, tc->snd_mss); - scoreboard_clear (&tc->sack_sb); +static int +tcp_send_acks (tcp_connection_t * tc, u32 max_burst_size) +{ + int j, n_acks; - if (n_bytes == 0) + if (!tc->pending_dupacks) + { + if (tcp_in_cong_recovery (tc) || !tcp_max_tx_deq (tc) + || tc->state != TCP_STATE_ESTABLISHED) { - clib_warning ("could not retransmit"); - return; + tcp_send_ack (tc); + return 1; } + return 0; } - else - { - /* Retransmit for SYN/SYNACK */ - ASSERT (tc->state == TCP_STATE_SYN_RCVD - || tc->state == TCP_STATE_SYN_SENT); - - /* Try without increasing RTO a number of times. If this fails, - * start growing RTO exponentially */ - if (tc->rto_boff > TCP_RTO_SYN_RETRIES) - tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX); - vlib_buffer_make_headroom (b, MAX_HDRS_LEN); + /* If we're supposed to send dupacks but have no ooo data + * send only one ack */ + if (!vec_len (tc->snd_sacks)) + { + tcp_send_ack (tc); + tc->dupacks_out += 1; + tc->pending_dupacks = 0; + return 1; + } - tcp_push_hdr_i (tc, b, tc->state, 1); + /* Start with first sack block */ + tc->snd_sack_pos = 0; - /* Account for the SYN */ - tc->snd_nxt += 1; - } + /* Generate enough dupacks to cover all sack blocks. Do not generate + * more sacks than the number of packets received. But do generate at + * least 3, i.e., the number needed to signal congestion, if needed. */ + n_acks = vec_len (tc->snd_sacks) / TCP_OPTS_MAX_SACK_BLOCKS; + n_acks = clib_min (n_acks, tc->pending_dupacks); + n_acks = clib_max (n_acks, clib_min (tc->pending_dupacks, 3)); + for (j = 0; j < clib_min (n_acks, max_burst_size); j++) + tcp_send_ack (tc); - if (!is_syn) + if (n_acks < max_burst_size) { - tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4); - - /* Re-enable retransmit timer */ - tcp_retransmit_timer_set (tc); + tc->pending_dupacks = 0; + tc->snd_sack_pos = 0; + tc->dupacks_out += n_acks; + return n_acks; } else { - ASSERT (tc->state == TCP_STATE_SYN_SENT); - - TCP_EVT_DBG (TCP_EVT_SYN_RTX, tc); - - /* This goes straight to ipx_lookup */ - tcp_push_ip_hdr (tm, tc, b); - tcp_enqueue_to_ip_lookup (vm, b, bi, tc->c_is_ip4); - - /* Re-enable retransmit timer */ - tcp_timer_set (tc, TCP_TIMER_RETRANSMIT_SYN, - tc->rto * TCP_TO_TIMER_TICK); + TCP_DBG ("constrained by burst size"); + tc->pending_dupacks = n_acks - max_burst_size; + tc->dupacks_out += max_burst_size; + tcp_program_dupack (tc); + return max_burst_size; } } -void -tcp_timer_retransmit_handler (u32 index) +static int +tcp_do_retransmit (tcp_connection_t * tc, u32 max_burst_size) { - tcp_timer_retransmit_handler_i (index, 0); -} + tcp_worker_ctx_t *wrk; + u32 n_segs; -void -tcp_timer_retransmit_syn_handler (u32 index) -{ - tcp_timer_retransmit_handler_i (index, 1); + if (PREDICT_FALSE (tc->state == TCP_STATE_CLOSED)) + return 0; + + wrk = tcp_get_worker (tc->c_thread_index); + + if (tcp_opts_sack_permitted (&tc->rcv_opts)) + n_segs = tcp_retransmit_sack (wrk, tc, max_burst_size); + else + n_segs = tcp_retransmit_no_sack (wrk, tc, max_burst_size); + + return n_segs; } -/** - * Got 0 snd_wnd from peer, try to do something about it. - * - */ -void -tcp_timer_persist_handler (u32 index) +int +tcp_session_custom_tx (void *conn, u32 max_burst_size) { - tcp_main_t *tm = vnet_get_tcp_main (); - vlib_main_t *vm = vlib_get_main (); - u32 thread_index = vlib_get_thread_index (); - tcp_connection_t *tc; - vlib_buffer_t *b; - u32 bi, n_bytes; + tcp_connection_t *tc = (tcp_connection_t *) conn; + u32 n_segs = 0; - tc = tcp_connection_get (index, thread_index); + if (tcp_in_cong_recovery (tc) && (tc->flags & TCP_CONN_RXT_PENDING)) + { + tc->flags &= ~TCP_CONN_RXT_PENDING; + n_segs = tcp_do_retransmit (tc, max_burst_size); + max_burst_size -= n_segs; + } - /* Make sure timer handle is set to invalid */ - tc->timers[TCP_TIMER_PERSIST] = TCP_TIMER_HANDLE_INVALID; + if (!(tc->flags & TCP_CONN_SNDACK)) + return n_segs; - /* Problem already solved or worse */ - if (tc->snd_wnd > tc->snd_mss || tcp_in_recovery (tc)) - return; + tc->flags &= ~TCP_CONN_SNDACK; - /* Increment RTO backoff */ - tc->rto_boff += 1; - tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX); + /* We have retransmitted packets and no dupack */ + if (n_segs && !tc->pending_dupacks) + return n_segs; - /* Try to force the first unsent segment */ - tcp_get_free_buffer_index (tm, &bi); - b = vlib_get_buffer (vm, bi); - tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state); - n_bytes = stream_session_peek_bytes (&tc->connection, - vlib_buffer_get_current (b), - tc->snd_una_max - tc->snd_una, - tc->snd_mss); - /* Nothing to send */ - if (n_bytes == 0) - { - tcp_return_buffer (tm); - return; + if (!max_burst_size) + { + tcp_program_ack (tc); + return max_burst_size; } - b->current_length = n_bytes; - tcp_push_hdr_i (tc, b, tc->state, 0); - tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4); + n_segs += tcp_send_acks (tc, max_burst_size); - /* Re-enable persist timer */ - tcp_persist_timer_set (tc); + return n_segs; } +#endif /* CLIB_MARCH_VARIANT */ -/** - * Retransmit first unacked segment - */ -void -tcp_retransmit_first_unacked (tcp_connection_t * tc) +static void +tcp_output_handle_link_local (tcp_connection_t * tc0, vlib_buffer_t * b0, + u16 * next0, u32 * error0) { - tcp_main_t *tm = vnet_get_tcp_main (); - vlib_main_t *vm = vlib_get_main (); - vlib_buffer_t *b; - u32 bi, n_bytes; - - tc->snd_nxt = tc->snd_una; - - /* Get buffer */ - tcp_get_free_buffer_index (tm, &bi); - b = vlib_get_buffer (vm, bi); - - TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 2); + ip_adjacency_t *adj; + adj_index_t ai; + + /* Not thread safe but as long as the connection exists the adj should + * not be removed */ + ai = adj_nbr_find (FIB_PROTOCOL_IP6, VNET_LINK_IP6, &tc0->c_rmt_ip, + tc0->sw_if_index); + if (ai == ADJ_INDEX_INVALID) + { + vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0; + *next0 = TCP_OUTPUT_NEXT_DROP; + *error0 = TCP_ERROR_LINK_LOCAL_RW; + return; + } - n_bytes = tcp_prepare_retransmit_segment (tc, b, 0, tc->snd_mss); - if (n_bytes == 0) - goto done; + adj = adj_get (ai); + if (PREDICT_TRUE (adj->lookup_next_index == IP_LOOKUP_NEXT_REWRITE)) + *next0 = TCP_OUTPUT_NEXT_IP_REWRITE; + else if (adj->lookup_next_index == IP_LOOKUP_NEXT_ARP) + *next0 = TCP_OUTPUT_NEXT_IP_ARP; + else + { + *next0 = TCP_OUTPUT_NEXT_DROP; + *error0 = TCP_ERROR_LINK_LOCAL_RW; + } + vnet_buffer (b0)->ip.adj_index[VLIB_TX] = ai; +} - tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4); +static void +tcp46_output_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node, + u32 * to_next, u32 n_bufs) +{ + tcp_connection_t *tc; + tcp_tx_trace_t *t; + vlib_buffer_t *b; + tcp_header_t *th; + int i; -done: - tc->snd_nxt = tc->snd_una_max; + for (i = 0; i < n_bufs; i++) + { + b = vlib_get_buffer (vm, to_next[i]); + if (!(b->flags & VLIB_BUFFER_IS_TRACED)) + continue; + th = vlib_buffer_get_current (b); + tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index, + vm->thread_index); + t = vlib_add_trace (vm, node, b, sizeof (*t)); + clib_memcpy_fast (&t->tcp_header, th, sizeof (t->tcp_header)); + clib_memcpy_fast (&t->tcp_connection, tc, sizeof (t->tcp_connection)); + } } -sack_scoreboard_hole_t * -scoreboard_first_rtx_hole (sack_scoreboard_t * sb) +always_inline void +tcp_output_push_ip (vlib_main_t * vm, vlib_buffer_t * b0, + tcp_connection_t * tc0, u8 is_ip4) { - sack_scoreboard_hole_t *hole = 0; + TCP_EVT (TCP_EVT_OUTPUT, tc0, + ((tcp_header_t *) vlib_buffer_get_current (b0))->flags, + b0->current_length); -// hole = scoreboard_first_hole (&tc->sack_sb); -// if (hole) -// { -// -// offset = hole->start - tc->snd_una; -// hole_size = hole->end - hole->start; -// -// ASSERT(hole_size); -// -// if (hole_size < max_bytes) -// max_bytes = hole_size; -// } - return hole; + if (is_ip4) + vlib_buffer_push_ip4 (vm, b0, &tc0->c_lcl_ip4, &tc0->c_rmt_ip4, + IP_PROTOCOL_TCP, tcp_csum_offload (tc0)); + else + vlib_buffer_push_ip6_custom (vm, b0, &tc0->c_lcl_ip6, &tc0->c_rmt_ip6, + IP_PROTOCOL_TCP, tc0->ipv6_flow_label); } -/** - * Do fast retransmit. - */ -void -tcp_fast_retransmit (tcp_connection_t * tc) +always_inline void +tcp_check_if_gso (tcp_connection_t * tc, vlib_buffer_t * b) { - tcp_main_t *tm = vnet_get_tcp_main (); - vlib_main_t *vm = vlib_get_main (); - u32 bi; - int snd_space; - u32 n_written = 0, offset = 0; - vlib_buffer_t *b; - u8 use_sacks = 0; - - ASSERT (tcp_in_fastrecovery (tc)); + if (PREDICT_TRUE (!(tc->cfg_flags & TCP_CFG_F_TSO))) + return; - /* Start resending from first un-acked segment */ - tc->snd_nxt = tc->snd_una; + u16 data_len = b->current_length - sizeof (tcp_header_t) - tc->snd_opts_len; - snd_space = tcp_available_snd_space (tc); - TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 0); + if (PREDICT_FALSE (b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID)) + data_len += b->total_length_not_including_first_buffer; - /* If we have SACKs use them */ - if (tcp_opts_sack_permitted (&tc->opt) - && scoreboard_first_hole (&tc->sack_sb)) - use_sacks = 0; + if (PREDICT_TRUE (data_len <= tc->snd_mss)) + return; + else + { + ASSERT ((b->flags & VNET_BUFFER_F_L3_HDR_OFFSET_VALID) != 0); + ASSERT ((b->flags & VNET_BUFFER_F_L4_HDR_OFFSET_VALID) != 0); + b->flags |= VNET_BUFFER_F_GSO; + vnet_buffer2 (b)->gso_l4_hdr_sz = + sizeof (tcp_header_t) + tc->snd_opts_len; + vnet_buffer2 (b)->gso_size = tc->snd_mss; + } +} - while (snd_space > 0) +always_inline void +tcp_output_handle_packet (tcp_connection_t * tc0, vlib_buffer_t * b0, + vlib_node_runtime_t * error_node, u16 * next0, + u8 is_ip4) +{ + /* If next_index is not drop use it */ + if (tc0->next_node_index) { - tcp_get_free_buffer_index (tm, &bi); - b = vlib_get_buffer (vm, bi); + *next0 = tc0->next_node_index; + vnet_buffer (b0)->tcp.next_node_opaque = tc0->next_node_opaque; + } + else + { + *next0 = TCP_OUTPUT_NEXT_IP_LOOKUP; + } - if (use_sacks) - { - scoreboard_first_rtx_hole (&tc->sack_sb); - } - else - { - offset += n_written; - } + vnet_buffer (b0)->sw_if_index[VLIB_TX] = tc0->c_fib_index; + vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0; + + if (!is_ip4) + { + u32 error0 = 0; - n_written = tcp_prepare_retransmit_segment (tc, b, offset, snd_space); + if (PREDICT_FALSE (ip6_address_is_link_local_unicast (&tc0->c_rmt_ip6))) + tcp_output_handle_link_local (tc0, b0, next0, &error0); - /* Nothing left to retransmit */ - if (n_written == 0) + if (PREDICT_FALSE (error0)) { - tcp_return_buffer (tm); - break; + b0->error = error_node->errors[error0]; + return; } - - tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4); - snd_space -= n_written; } - /* If window allows, send 1 SMSS of new data */ - if (seq_lt (tc->snd_nxt, tc->snd_congestion)) - tc->snd_nxt = tc->snd_congestion; -} + if (!TCP_ALWAYS_ACK) + tcp_timer_reset (tc0, TCP_TIMER_DELACK); -always_inline u32 -tcp_session_has_ooo_data (tcp_connection_t * tc) -{ - stream_session_t *s = - stream_session_get (tc->c_s_index, tc->c_thread_index); - return svm_fifo_has_ooo_data (s->server_rx_fifo); + tc0->segs_out += 1; } always_inline uword -tcp46_output_inline (vlib_main_t * vm, - vlib_node_runtime_t * node, - vlib_frame_t * from_frame, int is_ip4) +tcp46_output_inline (vlib_main_t * vm, vlib_node_runtime_t * node, + vlib_frame_t * frame, int is_ip4) { - u32 n_left_from, next_index, *from, *to_next; - u32 my_thread_index = vm->thread_index; + u32 n_left_from, *from, thread_index = vm->thread_index; + vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b; + u16 nexts[VLIB_FRAME_SIZE], *next; + vlib_node_runtime_t *error_node; - from = vlib_frame_vector_args (from_frame); - n_left_from = from_frame->n_vectors; + error_node = vlib_node_get_runtime (vm, tcp_node_index (output, is_ip4)); - next_index = node->cached_next_index; + from = vlib_frame_vector_args (frame); + n_left_from = frame->n_vectors; + tcp_set_time_now (tcp_get_worker (thread_index)); - while (n_left_from > 0) + if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE)) + tcp46_output_trace_frame (vm, node, from, n_left_from); + + vlib_get_buffers (vm, from, bufs, n_left_from); + b = bufs; + next = nexts; + + while (n_left_from >= 4) { - u32 n_left_to_next; + tcp_connection_t *tc0, *tc1; - vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); + { + vlib_prefetch_buffer_header (b[2], STORE); + CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE); - while (n_left_from > 0 && n_left_to_next > 0) - { - u32 bi0; - vlib_buffer_t *b0; - tcp_connection_t *tc0; - tcp_tx_trace_t *t0; - tcp_header_t *th0 = 0; - u32 error0 = TCP_ERROR_PKTS_SENT, next0 = TCP_OUTPUT_NEXT_IP_LOOKUP; + vlib_prefetch_buffer_header (b[3], STORE); + CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE); + } - bi0 = from[0]; - to_next[0] = bi0; - from += 1; - to_next += 1; - n_left_from -= 1; - n_left_to_next -= 1; + tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index, + thread_index); + tc1 = tcp_connection_get (vnet_buffer (b[1])->tcp.connection_index, + thread_index); - b0 = vlib_get_buffer (vm, bi0); - tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index, - my_thread_index); - if (PREDICT_FALSE (tc0 == 0 || tc0->state == TCP_STATE_CLOSED)) - { - error0 = TCP_ERROR_INVALID_CONNECTION; - next0 = TCP_OUTPUT_NEXT_DROP; - goto done; - } + if (PREDICT_TRUE (!tc0 + !tc1 == 0)) + { + tcp_output_push_ip (vm, b[0], tc0, is_ip4); + tcp_output_push_ip (vm, b[1], tc1, is_ip4); - th0 = vlib_buffer_get_current (b0); - TCP_EVT_DBG (TCP_EVT_OUTPUT, tc0, th0->flags, b0->current_length); + tcp_check_if_gso (tc0, b[0]); + tcp_check_if_gso (tc1, b[1]); - if (is_ip4) + tcp_output_handle_packet (tc0, b[0], error_node, &next[0], is_ip4); + tcp_output_handle_packet (tc1, b[1], error_node, &next[1], is_ip4); + } + else + { + if (tc0 != 0) { - ip4_header_t *ih0; - ih0 = vlib_buffer_push_ip4 (vm, b0, &tc0->c_lcl_ip4, - &tc0->c_rmt_ip4, IP_PROTOCOL_TCP); - th0->checksum = ip4_tcp_udp_compute_checksum (vm, b0, ih0); + tcp_output_push_ip (vm, b[0], tc0, is_ip4); + tcp_check_if_gso (tc0, b[0]); + tcp_output_handle_packet (tc0, b[0], error_node, &next[0], + is_ip4); } else { - ip6_header_t *ih0; - int bogus = ~0; - - ih0 = vlib_buffer_push_ip6 (vm, b0, &tc0->c_lcl_ip6, - &tc0->c_rmt_ip6, IP_PROTOCOL_TCP); - th0->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b0, ih0, - &bogus); - ASSERT (!bogus); - } - - /* Filter out DUPACKs if there are no OOO segments left */ - if (PREDICT_FALSE - (vnet_buffer (b0)->tcp.flags & TCP_BUF_FLAG_DUPACK)) - { - if (!tcp_session_has_ooo_data (tc0)) - { - error0 = TCP_ERROR_FILTERED_DUPACKS; - next0 = TCP_OUTPUT_NEXT_DROP; - goto done; - } + b[0]->error = error_node->errors[TCP_ERROR_INVALID_CONNECTION]; + next[0] = TCP_OUTPUT_NEXT_DROP; } - - /* Stop DELACK timer and fix flags */ - tc0->flags &= ~(TCP_CONN_SNDACK); - if (tcp_timer_is_active (tc0, TCP_TIMER_DELACK)) + if (tc1 != 0) { - tcp_timer_reset (tc0, TCP_TIMER_DELACK); + tcp_output_push_ip (vm, b[1], tc1, is_ip4); + tcp_check_if_gso (tc1, b[1]); + tcp_output_handle_packet (tc1, b[1], error_node, &next[1], + is_ip4); } - - /* If not retransmitting - * 1) update snd_una_max (SYN, SYNACK, FIN) - * 2) If we're not tracking an ACK, start tracking */ - if (seq_lt (tc0->snd_una_max, tc0->snd_nxt)) + else { - tc0->snd_una_max = tc0->snd_nxt; - if (tc0->rtt_ts == 0) - { - tc0->rtt_ts = tcp_time_now (); - tc0->rtt_seq = tc0->snd_nxt; - } + b[1]->error = error_node->errors[TCP_ERROR_INVALID_CONNECTION]; + next[1] = TCP_OUTPUT_NEXT_DROP; } + } - /* Set the retransmit timer if not set already and not - * doing a pure ACK */ - if (!tcp_timer_is_active (tc0, TCP_TIMER_RETRANSMIT) - && tc0->snd_nxt != tc0->snd_una) - { - tcp_retransmit_timer_set (tc0); - tc0->rto_boff = 0; - } + b += 2; + next += 2; + n_left_from -= 2; + } + while (n_left_from > 0) + { + tcp_connection_t *tc0; - /* set fib index to default and lookup node */ - /* XXX network virtualization (vrf/vni) */ - vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0; - vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0; + if (n_left_from > 1) + { + vlib_prefetch_buffer_header (b[1], STORE); + CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE); + } - b0->flags |= VNET_BUFFER_LOCALLY_ORIGINATED; - done: - b0->error = node->errors[error0]; - if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED)) - { - t0 = vlib_add_trace (vm, node, b0, sizeof (*t0)); - if (th0) - { - clib_memcpy (&t0->tcp_header, th0, sizeof (t0->tcp_header)); - } - else - { - memset (&t0->tcp_header, 0, sizeof (t0->tcp_header)); - } - clib_memcpy (&t0->tcp_connection, tc0, - sizeof (t0->tcp_connection)); - } + tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index, + thread_index); - vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, - n_left_to_next, bi0, next0); + if (PREDICT_TRUE (tc0 != 0)) + { + tcp_output_push_ip (vm, b[0], tc0, is_ip4); + tcp_check_if_gso (tc0, b[0]); + tcp_output_handle_packet (tc0, b[0], error_node, &next[0], is_ip4); + } + else + { + b[0]->error = error_node->errors[TCP_ERROR_INVALID_CONNECTION]; + next[0] = TCP_OUTPUT_NEXT_DROP; } - vlib_put_next_frame (vm, node, next_index, n_left_to_next); + b += 1; + next += 1; + n_left_from -= 1; } - return from_frame->n_vectors; + vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors); + vlib_node_increment_counter (vm, tcp_node_index (output, is_ip4), + TCP_ERROR_PKTS_SENT, frame->n_vectors); + return frame->n_vectors; } -static uword -tcp4_output (vlib_main_t * vm, vlib_node_runtime_t * node, - vlib_frame_t * from_frame) +VLIB_NODE_FN (tcp4_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node, + vlib_frame_t * from_frame) { return tcp46_output_inline (vm, node, from_frame, 1 /* is_ip4 */ ); } -static uword -tcp6_output (vlib_main_t * vm, vlib_node_runtime_t * node, - vlib_frame_t * from_frame) +VLIB_NODE_FN (tcp6_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node, + vlib_frame_t * from_frame) { return tcp46_output_inline (vm, node, from_frame, 0 /* is_ip4 */ ); } @@ -1495,32 +2427,31 @@ tcp6_output (vlib_main_t * vm, vlib_node_runtime_t * node, /* *INDENT-OFF* */ VLIB_REGISTER_NODE (tcp4_output_node) = { - .function = tcp4_output,.name = "tcp4-output", - /* Takes a vector of packets. */ - .vector_size = sizeof (u32), - .n_errors = TCP_N_ERROR, - .error_strings = tcp_error_strings, - .n_next_nodes = TCP_OUTPUT_N_NEXT, - .next_nodes = { + .name = "tcp4-output", + /* Takes a vector of packets. */ + .vector_size = sizeof (u32), + .n_errors = TCP_N_ERROR, + .protocol_hint = VLIB_NODE_PROTO_HINT_TCP, + .error_strings = tcp_error_strings, + .n_next_nodes = TCP_OUTPUT_N_NEXT, + .next_nodes = { #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n, foreach_tcp4_output_next #undef _ - }, - .format_buffer = format_tcp_header, - .format_trace = format_tcp_tx_trace, + }, + .format_buffer = format_tcp_header, + .format_trace = format_tcp_tx_trace, }; /* *INDENT-ON* */ -VLIB_NODE_FUNCTION_MULTIARCH (tcp4_output_node, tcp4_output); - /* *INDENT-OFF* */ VLIB_REGISTER_NODE (tcp6_output_node) = { - .function = tcp6_output, .name = "tcp6-output", /* Takes a vector of packets. */ .vector_size = sizeof (u32), .n_errors = TCP_N_ERROR, + .protocol_hint = VLIB_NODE_PROTO_HINT_TCP, .error_strings = tcp_error_strings, .n_next_nodes = TCP_OUTPUT_N_NEXT, .next_nodes = { @@ -1533,18 +2464,6 @@ VLIB_REGISTER_NODE (tcp6_output_node) = }; /* *INDENT-ON* */ -VLIB_NODE_FUNCTION_MULTIARCH (tcp6_output_node, tcp6_output); - -u32 -tcp_push_header (transport_connection_t * tconn, vlib_buffer_t * b) -{ - tcp_connection_t *tc; - - tc = (tcp_connection_t *) tconn; - tcp_push_hdr_i (tc, b, TCP_STATE_ESTABLISHED, 0); - return 0; -} - typedef enum _tcp_reset_next { TCP_RESET_NEXT_DROP, @@ -1564,8 +2483,8 @@ static uword tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * from_frame, u8 is_ip4) { + u32 error0 = TCP_ERROR_RST_SENT, next0 = TCP_RESET_NEXT_IP_LOOKUP; u32 n_left_from, next_index, *from, *to_next; - u32 my_thread_index = vm->thread_index; from = vlib_frame_vector_args (from_frame); n_left_from = from_frame->n_vectors; @@ -1580,11 +2499,10 @@ tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node, while (n_left_from > 0 && n_left_to_next > 0) { - u32 bi0; vlib_buffer_t *b0; tcp_tx_trace_t *t0; tcp_header_t *th0; - u32 error0 = TCP_ERROR_RST_SENT, next0 = TCP_RESET_NEXT_IP_LOOKUP; + u32 bi0; bi0 = from[0]; to_next[0] = bi0; @@ -1594,22 +2512,13 @@ tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node, n_left_to_next -= 1; b0 = vlib_get_buffer (vm, bi0); - - if (tcp_make_reset_in_place (vm, b0, vnet_buffer (b0)->tcp.flags, - my_thread_index, is_ip4)) - { - error0 = TCP_ERROR_LOOKUP_DROPS; - next0 = TCP_RESET_NEXT_DROP; - goto done; - } + tcp_make_reset_in_place (vm, b0, is_ip4); /* Prepare to send to IP lookup */ - vnet_buffer (b0)->sw_if_index[VLIB_TX] = 0; - next0 = TCP_RESET_NEXT_IP_LOOKUP; + vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0; - done: b0->error = node->errors[error0]; - b0->flags |= VNET_BUFFER_LOCALLY_ORIGINATED; + b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED; if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED)) { th0 = vlib_buffer_get_current (b0); @@ -1618,7 +2527,8 @@ tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node, else th0 = ip6_next_header ((ip6_header_t *) th0); t0 = vlib_add_trace (vm, node, b0, sizeof (*t0)); - clib_memcpy (&t0->tcp_header, th0, sizeof (t0->tcp_header)); + clib_memcpy_fast (&t0->tcp_header, th0, + sizeof (t0->tcp_header)); } vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, @@ -1629,23 +2539,20 @@ tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node, return from_frame->n_vectors; } -static uword -tcp4_send_reset (vlib_main_t * vm, vlib_node_runtime_t * node, - vlib_frame_t * from_frame) +VLIB_NODE_FN (tcp4_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node, + vlib_frame_t * from_frame) { return tcp46_send_reset_inline (vm, node, from_frame, 1); } -static uword -tcp6_send_reset (vlib_main_t * vm, vlib_node_runtime_t * node, - vlib_frame_t * from_frame) +VLIB_NODE_FN (tcp6_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node, + vlib_frame_t * from_frame) { return tcp46_send_reset_inline (vm, node, from_frame, 0); } /* *INDENT-OFF* */ VLIB_REGISTER_NODE (tcp4_reset_node) = { - .function = tcp4_send_reset, .name = "tcp4-reset", .vector_size = sizeof (u32), .n_errors = TCP_N_ERROR, @@ -1660,11 +2567,8 @@ VLIB_REGISTER_NODE (tcp4_reset_node) = { }; /* *INDENT-ON* */ -VLIB_NODE_FUNCTION_MULTIARCH (tcp4_reset_node, tcp4_send_reset); - /* *INDENT-OFF* */ VLIB_REGISTER_NODE (tcp6_reset_node) = { - .function = tcp6_send_reset, .name = "tcp6-reset", .vector_size = sizeof (u32), .n_errors = TCP_N_ERROR, @@ -1679,8 +2583,6 @@ VLIB_REGISTER_NODE (tcp6_reset_node) = { }; /* *INDENT-ON* */ -VLIB_NODE_FUNCTION_MULTIARCH (tcp6_reset_node, tcp6_send_reset); - /* * fd.io coding-style-patch-verification: ON *