| /* |
| * 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. |
| */ |
| |
| #include <vnet/tcp/tcp.h> |
| #include <vnet/lisp-cp/packets.h> |
| #include <math.h> |
| |
| vlib_node_registration_t tcp4_output_node; |
| vlib_node_registration_t tcp6_output_node; |
| |
| 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_REWRITE, "ip4-rewrite") \ |
| _ (IP_ARP, "ip4-arp") |
| |
| #define foreach_tcp6_output_next \ |
| _ (DROP, "error-drop") \ |
| _ (IP_LOOKUP, "ip6-lookup") \ |
| _ (IP_REWRITE, "ip6-rewrite") \ |
| _ (IP_ARP, "ip6-discover-neighbor") |
| |
| static char *tcp_error_strings[] = { |
| #define tcp_error(n,s) s, |
| #include <vnet/tcp/tcp_error.def> |
| #undef tcp_error |
| }; |
| |
| typedef struct |
| { |
| tcp_header_t tcp_header; |
| tcp_connection_t tcp_connection; |
| } tcp_tx_trace_t; |
| |
| u16 dummy_mtu = 1460; |
| |
| 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 *); |
| 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, &t->tcp_connection, 1); |
| |
| return s; |
| } |
| |
| static u8 |
| tcp_window_compute_scale (u32 window) |
| { |
| u8 wnd_scale = 0; |
| while (wnd_scale < TCP_MAX_WND_SCALE && (window >> wnd_scale) > TCP_WND_MAX) |
| wnd_scale++; |
| return wnd_scale; |
| } |
| |
| /** |
| * Update max segment size we're able to process. |
| * |
| * The value is constrained by our interface's MTU and IP options. It is |
| * also what we advertise to our peer. |
| */ |
| void |
| tcp_update_rcv_mss (tcp_connection_t * tc) |
| { |
| /* TODO find our iface MTU */ |
| tc->mss = dummy_mtu - sizeof (tcp_header_t); |
| } |
| |
| /** |
| * TCP's initial window |
| */ |
| always_inline u32 |
| tcp_initial_wnd_unscaled (tcp_connection_t * tc) |
| { |
| /* 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_MIN_RX_FIFO_SIZE; |
| } |
| |
| /** |
| * Compute initial window and scale factor. As per RFC1323, window field in |
| * SYN and SYN-ACK segments is never scaled. |
| */ |
| 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; |
| |
| 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 |
| tcp_update_rcv_wnd (tcp_connection_t * tc) |
| { |
| i32 observed_wnd; |
| u32 available_space, max_fifo, wnd; |
| |
| /* |
| * Figure out how much space we have available |
| */ |
| available_space = transport_max_rx_enqueue (&tc->connection); |
| max_fifo = transport_rx_fifo_size (&tc->connection); |
| |
| ASSERT (tc->rcv_opts.mss < max_fifo); |
| if (available_space < tc->rcv_opts.mss && available_space < max_fifo >> 3) |
| available_space = 0; |
| |
| /* |
| * 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) |
| { |
| wnd = observed_wnd; |
| TCP_EVT_DBG (TCP_EVT_RCV_WND_SHRUNK, tc, observed_wnd, available_space); |
| } |
| else |
| { |
| wnd = available_space; |
| } |
| |
| /* Make sure we have a multiple of rcv_wscale */ |
| if (wnd && tc->rcv_wscale) |
| { |
| wnd &= ~(1 << tc->rcv_wscale); |
| if (wnd == 0) |
| wnd = 1 << tc->rcv_wscale; |
| } |
| |
| tc->rcv_wnd = clib_min (wnd, TCP_WND_MAX << tc->rcv_wscale); |
| } |
| |
| /** |
| * Write TCP options to segment. |
| */ |
| u32 |
| tcp_options_write (u8 * data, tcp_options_t * opts) |
| { |
| u32 opts_len = 0; |
| u32 buf, seq_len = 4; |
| |
| if (tcp_opts_mss (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)); |
| data += sizeof (opts->mss); |
| opts_len += TCP_OPTION_LEN_MSS; |
| } |
| |
| if (tcp_opts_wscale (opts)) |
| { |
| *data++ = TCP_OPTION_WINDOW_SCALE; |
| *data++ = TCP_OPTION_LEN_WINDOW_SCALE; |
| *data++ = opts->wscale; |
| opts_len += TCP_OPTION_LEN_WINDOW_SCALE; |
| } |
| |
| if (tcp_opts_sack_permitted (opts)) |
| { |
| *data++ = TCP_OPTION_SACK_PERMITTED; |
| *data++ = TCP_OPTION_LEN_SACK_PERMITTED; |
| opts_len += TCP_OPTION_LEN_SACK_PERMITTED; |
| } |
| |
| if (tcp_opts_tstamp (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)); |
| data += sizeof (opts->tsval); |
| buf = clib_host_to_net_u32 (opts->tsecr); |
| clib_memcpy (data, &buf, sizeof (opts->tsecr)); |
| data += sizeof (opts->tsecr); |
| opts_len += TCP_OPTION_LEN_TIMESTAMP; |
| } |
| |
| 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) |
| { |
| *data++ = TCP_OPTION_SACK_BLOCK; |
| *data++ = 2 + n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK; |
| for (i = 0; i < n_sack_blocks; i++) |
| { |
| buf = clib_host_to_net_u32 (opts->sacks[i].start); |
| clib_memcpy (data, &buf, seq_len); |
| data += seq_len; |
| buf = clib_host_to_net_u32 (opts->sacks[i].end); |
| clib_memcpy (data, &buf, seq_len); |
| data += seq_len; |
| } |
| opts_len += 2 + n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK; |
| } |
| } |
| |
| /* Terminate TCP options */ |
| if (opts_len % 4) |
| { |
| *data++ = TCP_OPTION_EOL; |
| opts_len += TCP_OPTION_LEN_EOL; |
| } |
| |
| /* Pad with zeroes to a u32 boundary */ |
| while (opts_len % 4) |
| { |
| *data++ = TCP_OPTION_NOOP; |
| opts_len += TCP_OPTION_LEN_NOOP; |
| } |
| return opts_len; |
| } |
| |
| always_inline int |
| tcp_make_syn_options (tcp_options_t * opts, u8 wnd_scale) |
| { |
| u8 len = 0; |
| |
| opts->flags |= TCP_OPTS_FLAG_MSS; |
| opts->mss = dummy_mtu; /*XXX discover that */ |
| len += TCP_OPTION_LEN_MSS; |
| |
| opts->flags |= TCP_OPTS_FLAG_WSCALE; |
| opts->wscale = wnd_scale; |
| len += TCP_OPTION_LEN_WINDOW_SCALE; |
| |
| opts->flags |= TCP_OPTS_FLAG_TSTAMP; |
| opts->tsval = tcp_time_now (); |
| opts->tsecr = 0; |
| len += TCP_OPTION_LEN_TIMESTAMP; |
| |
| 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 |
| tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts) |
| { |
| u8 len = 0; |
| |
| opts->flags |= TCP_OPTS_FLAG_MSS; |
| opts->mss = tc->mss; |
| len += TCP_OPTION_LEN_MSS; |
| |
| 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->rcv_opts)) |
| { |
| opts->flags |= TCP_OPTS_FLAG_TSTAMP; |
| opts->tsval = tcp_time_now (); |
| opts->tsecr = tc->tsval_recent; |
| len += TCP_OPTION_LEN_TIMESTAMP; |
| } |
| |
| if (tcp_opts_sack_permitted (&tc->rcv_opts)) |
| { |
| 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 |
| tcp_make_established_options (tcp_connection_t * tc, tcp_options_t * opts) |
| { |
| u8 len = 0; |
| |
| opts->flags = 0; |
| |
| if (tcp_opts_tstamp (&tc->rcv_opts)) |
| { |
| opts->flags |= TCP_OPTS_FLAG_TSTAMP; |
| opts->tsval = tcp_time_now (); |
| opts->tsecr = tc->tsval_recent; |
| len += TCP_OPTION_LEN_TIMESTAMP; |
| } |
| 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), |
| TCP_OPTS_MAX_SACK_BLOCKS); |
| len += 2 + TCP_OPTION_LEN_SACK_BLOCK * opts->n_sack_blocks; |
| } |
| } |
| |
| /* Align to needed boundary */ |
| len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN; |
| return len; |
| } |
| |
| always_inline int |
| tcp_make_options (tcp_connection_t * tc, tcp_options_t * opts, |
| tcp_state_t state) |
| { |
| switch (state) |
| { |
| case TCP_STATE_ESTABLISHED: |
| case TCP_STATE_FIN_WAIT_1: |
| 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); |
| default: |
| clib_warning ("State not handled! %d", state); |
| return 0; |
| } |
| } |
| |
| /** |
| * 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); |
| |
| /* XXX check if MTU has been updated */ |
| tc->snd_mss = clib_min (tc->mss, tc->rcv_opts.mss) - tc->snd_opts_len; |
| ASSERT (tc->snd_mss > 0); |
| } |
| |
| void |
| tcp_init_mss (tcp_connection_t * tc) |
| { |
| u16 default_min_mss = 536; |
| tcp_update_rcv_mss (tc); |
| |
| /* TODO cache mss and consider PMTU discovery */ |
| tc->snd_mss = clib_min (tc->rcv_opts.mss, tc->mss); |
| |
| if (tc->snd_mss < 45) |
| { |
| clib_warning ("snd mss is 0"); |
| /* Assume that at least the min default mss works */ |
| tc->snd_mss = default_min_mss; |
| tc->rcv_opts.mss = default_min_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->rcv_opts)) |
| tc->snd_mss -= TCP_OPTION_LEN_TIMESTAMP; |
| } |
| |
| always_inline int |
| tcp_alloc_tx_buffers (tcp_main_t * tm, u8 thread_index, u16 * n_bufs, |
| u32 wanted) |
| { |
| vlib_main_t *vm = vlib_get_main (); |
| u32 n_alloc; |
| |
| ASSERT (wanted > *n_bufs); |
| vec_validate_aligned (tm->tx_buffers[thread_index], wanted - 1, |
| CLIB_CACHE_LINE_BYTES); |
| n_alloc = vlib_buffer_alloc (vm, &tm->tx_buffers[thread_index][*n_bufs], |
| wanted - *n_bufs); |
| *n_bufs += n_alloc; |
| _vec_len (tm->tx_buffers[thread_index]) = *n_bufs; |
| return n_alloc; |
| } |
| |
| always_inline int |
| tcp_get_free_buffer_index (tcp_main_t * tm, u32 * bidx) |
| { |
| u32 thread_index = vlib_get_thread_index (); |
| u16 n_bufs = vec_len (tm->tx_buffers[thread_index]); |
| |
| TCP_DBG_BUFFER_ALLOC_MAYBE_FAIL (thread_index); |
| |
| if (PREDICT_FALSE (!n_bufs)) |
| { |
| if (!tcp_alloc_tx_buffers (tm, thread_index, &n_bufs, VLIB_FRAME_SIZE)) |
| { |
| *bidx = ~0; |
| return -1; |
| } |
| } |
| *bidx = tm->tx_buffers[thread_index][--n_bufs]; |
| _vec_len (tm->tx_buffers[thread_index]) = n_bufs; |
| return 0; |
| } |
| |
| always_inline void * |
| tcp_reuse_buffer (vlib_main_t * vm, vlib_buffer_t * b) |
| { |
| 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 */ |
| return vlib_buffer_make_headroom (b, MAX_HDRS_LEN); |
| } |
| |
| always_inline void * |
| tcp_init_buffer (vlib_main_t * vm, vlib_buffer_t * b) |
| { |
| ASSERT ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0); |
| b->flags &= VLIB_BUFFER_NON_DEFAULT_FREELIST; |
| 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, MAX_HDRS_LEN); |
| } |
| |
| /** |
| * Prepare ACK |
| */ |
| void |
| tcp_make_ack_i (tcp_connection_t * tc, vlib_buffer_t * b, tcp_state_t state, |
| u8 flags) |
| { |
| tcp_options_t _snd_opts, *snd_opts = &_snd_opts; |
| u8 tcp_opts_len, tcp_hdr_opts_len; |
| tcp_header_t *th; |
| u16 wnd; |
| |
| wnd = tcp_window_to_advertise (tc, state); |
| |
| /* Make and write options */ |
| tcp_opts_len = tcp_make_established_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->snd_nxt, |
| tc->rcv_nxt, tcp_hdr_opts_len, flags, wnd); |
| |
| tcp_options_write ((u8 *) (th + 1), snd_opts); |
| vnet_buffer (b)->tcp.connection_index = tc->c_c_index; |
| } |
| |
| /** |
| * Convert buffer to ACK |
| */ |
| 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; |
| tc->rcv_las = tc->rcv_nxt; |
| } |
| |
| /** |
| * Convert buffer to FIN-ACK |
| */ |
| void |
| tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b) |
| { |
| vlib_main_t *vm = vlib_get_main (); |
| u8 flags = 0; |
| |
| tcp_reuse_buffer (vm, b); |
| |
| flags = TCP_FLAG_FIN | TCP_FLAG_ACK; |
| tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, flags); |
| |
| /* Reset flags, make sure ack is sent */ |
| vnet_buffer (b)->tcp.flags &= ~TCP_BUF_FLAG_DUPACK; |
| } |
| |
| /** |
| * 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; |
| |
| 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); |
| |
| 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); |
| } |
| |
| /** |
| * Convert buffer to SYN-ACK |
| */ |
| 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; |
| |
| memset (snd_opts, 0, sizeof (*snd_opts)); |
| tcp_reuse_buffer (vm, b); |
| |
| initial_wnd = tcp_initial_window_to_advertise (tc); |
| 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. Use update instead of set because of |
| * retransmissions */ |
| tcp_retransmit_timer_force_update (tc); |
| TCP_EVT_DBG (TCP_EVT_SYNACK_SENT, tc); |
| } |
| |
| always_inline void |
| tcp_enqueue_to_ip_lookup_i (vlib_main_t * vm, vlib_buffer_t * b, u32 bi, |
| u8 is_ip4, u32 fib_index, u8 flush) |
| { |
| tcp_main_t *tm = vnet_get_tcp_main (); |
| u32 thread_index = vlib_get_thread_index (); |
| u32 *to_next, next_index; |
| vlib_frame_t *f; |
| |
| b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED; |
| b->error = 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; |
| tcp_trajectory_add_start (b, 1); |
| |
| f = tm->ip_lookup_tx_frames[!is_ip4][thread_index]; |
| if (!f) |
| { |
| f = vlib_get_frame_to_node (vm, next_index); |
| ASSERT (f); |
| tm->ip_lookup_tx_frames[!is_ip4][thread_index] = f; |
| } |
| |
| to_next = vlib_frame_vector_args (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); |
| tm->ip_lookup_tx_frames[!is_ip4][thread_index] = 0; |
| } |
| } |
| |
| always_inline void |
| tcp_enqueue_to_ip_lookup_now (vlib_main_t * vm, vlib_buffer_t * b, u32 bi, |
| u8 is_ip4, u32 fib_index) |
| { |
| tcp_enqueue_to_ip_lookup_i (vm, b, bi, is_ip4, fib_index, 1); |
| } |
| |
| always_inline void |
| tcp_enqueue_to_ip_lookup (vlib_main_t * vm, vlib_buffer_t * b, u32 bi, |
| u8 is_ip4, u32 fib_index) |
| { |
| tcp_enqueue_to_ip_lookup_i (vm, b, bi, is_ip4, fib_index, 0); |
| if (vm->thread_index == 0 && vlib_num_workers ()) |
| session_flush_frames_main_thread (vm); |
| } |
| |
| always_inline void |
| tcp_enqueue_to_output_i (vlib_main_t * vm, vlib_buffer_t * b, u32 bi, |
| u8 is_ip4, u8 flush) |
| { |
| tcp_main_t *tm = vnet_get_tcp_main (); |
| u32 thread_index = vlib_get_thread_index (); |
| u32 *to_next, next_index; |
| vlib_frame_t *f; |
| |
| b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED; |
| b->error = 0; |
| |
| /* Decide where to send the packet */ |
| next_index = is_ip4 ? tcp4_output_node.index : tcp6_output_node.index; |
| tcp_trajectory_add_start (b, 2); |
| |
| /* Get frame to v4/6 output node */ |
| f = tm->tx_frames[!is_ip4][thread_index]; |
| if (!f) |
| { |
| f = vlib_get_frame_to_node (vm, next_index); |
| ASSERT (f); |
| tm->tx_frames[!is_ip4][thread_index] = f; |
| } |
| to_next = vlib_frame_vector_args (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); |
| tm->tx_frames[!is_ip4][thread_index] = 0; |
| } |
| } |
| |
| always_inline void |
| tcp_enqueue_to_output (vlib_main_t * vm, vlib_buffer_t * b, u32 bi, u8 is_ip4) |
| { |
| tcp_enqueue_to_output_i (vm, b, bi, is_ip4, 0); |
| } |
| |
| always_inline void |
| tcp_enqueue_to_output_now (vlib_main_t * vm, vlib_buffer_t * b, u32 bi, |
| u8 is_ip4) |
| { |
| tcp_enqueue_to_output_i (vm, b, bi, is_ip4, 1); |
| } |
| |
| int |
| tcp_make_reset_in_place (vlib_main_t * vm, vlib_buffer_t * b0, |
| tcp_state_t state, u8 thread_index, u8 is_ip4) |
| { |
| ip4_header_t *ih4; |
| ip6_header_t *ih6; |
| tcp_header_t *th0; |
| ip4_address_t src_ip40, dst_ip40; |
| ip6_address_t src_ip60, dst_ip60; |
| u16 src_port, dst_port; |
| u32 tmp; |
| u32 seq, ack; |
| u8 flags; |
| |
| /* Find IP and TCP headers */ |
| th0 = tcp_buffer_hdr (b0); |
| |
| /* Save src and dst ip */ |
| if (is_ip4) |
| { |
| ih4 = vlib_buffer_get_current (b0); |
| ASSERT ((ih4->ip_version_and_header_length & 0xF0) == 0x40); |
| src_ip40.as_u32 = ih4->src_address.as_u32; |
| dst_ip40.as_u32 = ih4->dst_address.as_u32; |
| } |
| else |
| { |
| ih6 = vlib_buffer_get_current (b0); |
| ASSERT ((ih6->ip_version_traffic_class_and_flow_label & 0xF0) == 0x60); |
| clib_memcpy (&src_ip60, &ih6->src_address, sizeof (ip6_address_t)); |
| clib_memcpy (&dst_ip60, &ih6->dst_address, sizeof (ip6_address_t)); |
| } |
| |
| src_port = th0->src_port; |
| dst_port = th0->dst_port; |
| |
| /* Try to determine what/why we're actually resetting */ |
| 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. */ |
| flags = TCP_FLAG_RST | TCP_FLAG_ACK; |
| ack = clib_host_to_net_u32 (tmp + 1); |
| seq = 0; |
| } |
| else |
| { |
| flags = TCP_FLAG_RST; |
| seq = th0->ack_number; |
| ack = 0; |
| } |
| |
| tcp_reuse_buffer (vm, b0); |
| tcp_trajectory_add_start (b0, 4); |
| th0 = vlib_buffer_push_tcp_net_order (b0, dst_port, src_port, seq, ack, |
| sizeof (tcp_header_t), flags, 0); |
| |
| if (is_ip4) |
| { |
| ih4 = vlib_buffer_push_ip4 (vm, b0, &dst_ip40, &src_ip40, |
| IP_PROTOCOL_TCP, 1); |
| th0->checksum = ip4_tcp_udp_compute_checksum (vm, b0, ih4); |
| } |
| else |
| { |
| int bogus = ~0; |
| ih6 = vlib_buffer_push_ip6 (vm, b0, &dst_ip60, &src_ip60, |
| IP_PROTOCOL_TCP); |
| th0->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b0, ih6, &bogus); |
| ASSERT (!bogus); |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * Send reset without reusing existing buffer |
| * |
| * It extracts connection info out of original packet |
| */ |
| void |
| tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt, u8 is_ip4) |
| { |
| vlib_buffer_t *b; |
| u32 bi, sw_if_index, fib_index; |
| tcp_main_t *tm = vnet_get_tcp_main (); |
| vlib_main_t *vm = vlib_get_main (); |
| 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; |
| |
| if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi))) |
| return; |
| |
| 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); |
| |
| if (is_ip4) |
| { |
| pkt_ih4 = vlib_buffer_get_current (pkt); |
| pkt_th = ip4_next_header (pkt_ih4); |
| } |
| else |
| { |
| pkt_ih6 = vlib_buffer_get_current (pkt); |
| pkt_th = ip6_next_header (pkt_ih6); |
| } |
| |
| if (tcp_ack (pkt_th)) |
| { |
| flags = TCP_FLAG_RST; |
| seq = pkt_th->ack_number; |
| ack = (tc && tc->state >= TCP_STATE_SYN_RCVD) ? tc->rcv_nxt : 0; |
| } |
| else |
| { |
| flags = TCP_FLAG_RST | TCP_FLAG_ACK; |
| seq = 0; |
| ack = clib_host_to_net_u32 (vnet_buffer (pkt)->tcp.seq_end); |
| } |
| |
| th = vlib_buffer_push_tcp_net_order (b, pkt_th->dst_port, pkt_th->src_port, |
| seq, ack, tcp_hdr_len, flags, 0); |
| |
| /* Swap src and dst ip */ |
| if (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, 1); |
| th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4); |
| } |
| else |
| { |
| int bogus = ~0; |
| 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); |
| th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus); |
| ASSERT (!bogus); |
| } |
| |
| tcp_enqueue_to_ip_lookup_now (vm, b, bi, is_ip4, fib_index); |
| TCP_EVT_DBG (TCP_EVT_RST_SENT, tc); |
| } |
| |
| /** |
| * Build and set reset packet for connection |
| */ |
| void |
| tcp_send_reset (tcp_connection_t * tc) |
| { |
| vlib_main_t *vm = vlib_get_main (); |
| tcp_main_t *tm = vnet_get_tcp_main (); |
| 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 (tcp_get_free_buffer_index (tm, &bi))) |
| 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); |
| ASSERT (opts_write_len == tc->snd_opts_len); |
| vnet_buffer (b)->tcp.connection_index = tc->c_c_index; |
| if (tc->c_is_ip4) |
| { |
| ip4_header_t *ih4; |
| ih4 = vlib_buffer_push_ip4 (vm, b, &tc->c_lcl_ip.ip4, |
| &tc->c_rmt_ip.ip4, IP_PROTOCOL_TCP, 0); |
| th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4); |
| } |
| else |
| { |
| int bogus = ~0; |
| ip6_header_t *ih6; |
| ih6 = vlib_buffer_push_ip6 (vm, b, &tc->c_lcl_ip.ip6, |
| &tc->c_rmt_ip.ip6, IP_PROTOCOL_TCP); |
| th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus); |
| ASSERT (!bogus); |
| } |
| tcp_enqueue_to_ip_lookup_now (vm, b, bi, tc->c_is_ip4, tc->c_fib_index); |
| TCP_EVT_DBG (TCP_EVT_RST_SENT, tc); |
| } |
| |
| void |
| tcp_push_ip_hdr (tcp_main_t * tm, tcp_connection_t * tc, vlib_buffer_t * b) |
| { |
| tcp_header_t *th = vlib_buffer_get_current (b); |
| vlib_main_t *vm = vlib_get_main (); |
| if (tc->c_is_ip4) |
| { |
| ip4_header_t *ih; |
| ih = vlib_buffer_push_ip4 (vm, b, &tc->c_lcl_ip4, |
| &tc->c_rmt_ip4, IP_PROTOCOL_TCP, 1); |
| th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih); |
| } |
| else |
| { |
| ip6_header_t *ih; |
| int bogus = ~0; |
| |
| ih = vlib_buffer_push_ip6 (vm, b, &tc->c_lcl_ip6, |
| &tc->c_rmt_ip6, IP_PROTOCOL_TCP); |
| th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih, &bogus); |
| ASSERT (!bogus); |
| } |
| } |
| |
| /** |
| * Send SYN |
| * |
| * Builds a SYN packet for a half-open connection and sends it to ipx_lookup. |
| * The packet is not forwarded through tcpx_output to avoid doing lookups |
| * in the half_open pool. |
| */ |
| void |
| tcp_send_syn (tcp_connection_t * tc) |
| { |
| vlib_buffer_t *b; |
| u32 bi; |
| tcp_main_t *tm = vnet_get_tcp_main (); |
| vlib_main_t *vm = vlib_get_main (); |
| |
| /* |
| * Setup retransmit and establish timers before requesting buffer |
| * such that we can return if we've ran out. |
| */ |
| tcp_timer_set (tc, TCP_TIMER_ESTABLISH, TCP_ESTABLISH_TIME); |
| tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN, |
| tc->rto * TCP_TO_TIMER_TICK); |
| |
| if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi))) |
| return; |
| |
| 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_seq = tc->snd_nxt; |
| tc->rto_boff = 0; |
| |
| tcp_push_ip_hdr (tm, tc, b); |
| tcp_enqueue_to_ip_lookup (vm, b, bi, tc->c_is_ip4, tc->c_fib_index); |
| TCP_EVT_DBG (TCP_EVT_SYN_SENT, tc); |
| } |
| |
| /** |
| * Flush tx frame populated by retransmits and timer pops |
| */ |
| void |
| tcp_flush_frame_to_output (vlib_main_t * vm, u8 thread_index, u8 is_ip4) |
| { |
| if (tcp_main.tx_frames[!is_ip4][thread_index]) |
| { |
| u32 next_index; |
| next_index = is_ip4 ? tcp4_output_node.index : tcp6_output_node.index; |
| vlib_put_frame_to_node (vm, next_index, |
| tcp_main.tx_frames[!is_ip4][thread_index]); |
| tcp_main.tx_frames[!is_ip4][thread_index] = 0; |
| } |
| } |
| |
| /** |
| * Flush ip lookup tx frames populated by timer pops |
| */ |
| always_inline void |
| tcp_flush_frame_to_ip_lookup (vlib_main_t * vm, u8 thread_index, u8 is_ip4) |
| { |
| if (tcp_main.ip_lookup_tx_frames[!is_ip4][thread_index]) |
| { |
| u32 next_index; |
| next_index = is_ip4 ? ip4_lookup_node.index : ip6_lookup_node.index; |
| vlib_put_frame_to_node (vm, next_index, |
| tcp_main.ip_lookup_tx_frames[!is_ip4] |
| [thread_index]); |
| tcp_main.ip_lookup_tx_frames[!is_ip4][thread_index] = 0; |
| } |
| } |
| |
| /** |
| * Flush v4 and v6 tcp and ip-lookup tx frames for thread index |
| */ |
| void |
| tcp_flush_frames_to_output (u8 thread_index) |
| { |
| vlib_main_t *vm = vlib_get_main (); |
| tcp_flush_frame_to_output (vm, thread_index, 1); |
| tcp_flush_frame_to_output (vm, thread_index, 0); |
| tcp_flush_frame_to_ip_lookup (vm, thread_index, 1); |
| tcp_flush_frame_to_ip_lookup (vm, thread_index, 0); |
| } |
| |
| /** |
| * Send FIN |
| */ |
| void |
| tcp_send_fin (tcp_connection_t * tc) |
| { |
| tcp_main_t *tm = vnet_get_tcp_main (); |
| vlib_main_t *vm = vlib_get_main (); |
| vlib_buffer_t *b; |
| u32 bi; |
| u8 fin_snt = 0; |
| |
| tcp_retransmit_timer_force_update (tc); |
| if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi))) |
| return; |
| b = vlib_get_buffer (vm, bi); |
| tcp_init_buffer (vm, b); |
| fin_snt = tc->flags & TCP_CONN_FINSNT; |
| if (fin_snt) |
| tc->snd_nxt = tc->snd_una; |
| tcp_make_fin (tc, b); |
| tcp_enqueue_to_output_now (vm, b, bi, tc->c_is_ip4); |
| if (!fin_snt) |
| { |
| tc->flags |= TCP_CONN_FINSNT; |
| tc->flags &= ~TCP_CONN_FINPNDG; |
| /* Account for the FIN */ |
| tc->snd_una_max += 1; |
| tc->snd_nxt = tc->snd_una_max; |
| } |
| else |
| { |
| tc->snd_nxt = tc->snd_una_max; |
| } |
| TCP_EVT_DBG (TCP_EVT_FIN_SENT, tc); |
| } |
| |
| always_inline u8 |
| tcp_make_state_flags (tcp_connection_t * tc, tcp_state_t next_state) |
| { |
| switch (next_state) |
| { |
| 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: |
| if (tc->snd_nxt + 1 < tc->snd_una_max) |
| return TCP_FLAG_ACK; |
| else |
| return TCP_FLAG_FIN; |
| default: |
| clib_warning ("Shouldn't be here!"); |
| } |
| return 0; |
| } |
| |
| /** |
| * Push TCP header and update connection variables |
| */ |
| static void |
| tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b, |
| tcp_state_t next_state, u8 compute_opts) |
| { |
| u32 advertise_wnd, data_len; |
| u8 tcp_hdr_opts_len, opts_write_len, flags; |
| tcp_header_t *th; |
| |
| data_len = b->current_length + b->total_length_not_including_first_buffer; |
| ASSERT (!b->total_length_not_including_first_buffer |
| || (b->flags & VLIB_BUFFER_NEXT_PRESENT)); |
| vnet_buffer (b)->tcp.flags = 0; |
| |
| if (compute_opts) |
| 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, next_state); |
| flags = tcp_make_state_flags (tc, next_state); |
| |
| /* Push header and options */ |
| 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); |
| |
| ASSERT (opts_write_len == tc->snd_opts_len); |
| vnet_buffer (b)->tcp.connection_index = tc->c_c_index; |
| |
| /* |
| * Update connection variables |
| */ |
| |
| tc->snd_nxt += data_len; |
| tc->rcv_las = tc->rcv_nxt; |
| |
| /* TODO this is updated in output as well ... */ |
| if (seq_gt (tc->snd_nxt, tc->snd_una_max)) |
| { |
| tc->snd_una_max = tc->snd_nxt; |
| tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una); |
| } |
| |
| TCP_EVT_DBG (TCP_EVT_PKTIZE, tc); |
| } |
| |
| void |
| tcp_send_ack (tcp_connection_t * tc) |
| { |
| tcp_main_t *tm = vnet_get_tcp_main (); |
| vlib_main_t *vm = vlib_get_main (); |
| |
| vlib_buffer_t *b; |
| u32 bi; |
| |
| /* Get buffer */ |
| if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi))) |
| return; |
| b = vlib_get_buffer (vm, bi); |
| tcp_init_buffer (vm, b); |
| |
| /* Fill in the ACK */ |
| tcp_make_ack (tc, b); |
| tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4); |
| } |
| |
| /** |
| * Delayed ack timer handler |
| * |
| * Sends delayed ACK when timer expires |
| */ |
| void |
| tcp_timer_delack_handler (u32 index) |
| { |
| u32 thread_index = vlib_get_thread_index (); |
| tcp_connection_t *tc; |
| |
| tc = tcp_connection_get (index, thread_index); |
| tc->timers[TCP_TIMER_DELACK] = TCP_TIMER_HANDLE_INVALID; |
| tcp_send_ack (tc); |
| } |
| |
| /** |
| * 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, u32 offset, |
| u32 max_deq_bytes, vlib_buffer_t ** b) |
| { |
| tcp_main_t *tm = vnet_get_tcp_main (); |
| vlib_main_t *vm = vlib_get_main (); |
| int n_bytes = 0; |
| u32 start, bi, available_bytes, seg_size; |
| u8 *data; |
| |
| ASSERT (tc->state >= TCP_STATE_ESTABLISHED); |
| ASSERT (max_deq_bytes != 0); |
| |
| /* |
| * Make sure we can retransmit something |
| */ |
| available_bytes = stream_session_tx_fifo_max_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 is beyond snd_congestion */ |
| start = tc->snd_una + offset; |
| if (seq_geq (start, tc->snd_congestion)) |
| goto done; |
| |
| /* Don't overshoot snd_congestion */ |
| if (seq_gt (start + max_deq_bytes, tc->snd_congestion)) |
| { |
| max_deq_bytes = tc->snd_congestion - start; |
| if (max_deq_bytes == 0) |
| goto done; |
| } |
| |
| seg_size = max_deq_bytes + 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 <= tm->bytes_per_buffer)) |
| { |
| if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi))) |
| return 0; |
| *b = vlib_get_buffer (vm, bi); |
| data = tcp_init_buffer (vm, *b); |
| n_bytes = stream_session_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->state, 0); |
| } |
| /* Split mss into multiple buffers */ |
| else |
| { |
| u32 chain_bi = ~0, n_bufs_per_seg; |
| u32 thread_index = vlib_get_thread_index (); |
| u16 n_peeked, len_to_deq, available_bufs; |
| vlib_buffer_t *chain_b, *prev_b; |
| int i; |
| |
| /* Make sure we have enough buffers */ |
| n_bufs_per_seg = ceil ((double) seg_size / tm->bytes_per_buffer); |
| available_bufs = vec_len (tm->tx_buffers[thread_index]); |
| if (n_bufs_per_seg > available_bufs) |
| { |
| tcp_alloc_tx_buffers (tm, thread_index, &available_bufs, |
| VLIB_FRAME_SIZE); |
| |
| if (n_bufs_per_seg > available_bufs) |
| { |
| *b = 0; |
| return 0; |
| } |
| } |
| |
| tcp_get_free_buffer_index (tm, &bi); |
| ASSERT (bi != (u32) ~ 0); |
| *b = vlib_get_buffer (vm, bi); |
| data = tcp_init_buffer (vm, *b); |
| n_bytes = stream_session_peek_bytes (&tc->connection, data, offset, |
| tm->bytes_per_buffer - |
| 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, tm->bytes_per_buffer); |
| tcp_get_free_buffer_index (tm, &chain_bi); |
| ASSERT (chain_bi != (u32) ~ 0); |
| chain_b = vlib_get_buffer (vm, chain_bi); |
| chain_b->current_data = 0; |
| data = vlib_buffer_get_current (chain_b); |
| n_peeked = stream_session_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->state, 0); |
| } |
| |
| ASSERT (n_bytes > 0); |
| ASSERT (((*b)->current_data + (*b)->current_length) <= |
| tm->bytes_per_buffer); |
| |
| if (tcp_in_fastrecovery (tc)) |
| tc->snd_rxt_bytes += n_bytes; |
| |
| done: |
| TCP_EVT_DBG (TCP_EVT_CC_RTX, tc, offset, n_bytes); |
| return n_bytes; |
| } |
| |
| /** |
| * Reset congestion control, switch cwnd to loss window and try again. |
| */ |
| static void |
| tcp_rtx_timeout_cc (tcp_connection_t * tc) |
| { |
| tc->prev_ssthresh = tc->ssthresh; |
| tc->prev_cwnd = tc->cwnd; |
| |
| /* Cleanly recover cc (also clears up fast retransmit) */ |
| if (tcp_in_fastrecovery (tc)) |
| tcp_cc_fastrecovery_exit (tc); |
| |
| /* Start again from the beginning */ |
| tc->cc_algo->congestion (tc); |
| tc->cwnd = tcp_loss_wnd (tc); |
| tc->snd_congestion = tc->snd_una_max; |
| tc->rtt_ts = 0; |
| tc->cwnd_acc_bytes = 0; |
| |
| 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 = 0; |
| u32 bi, n_bytes; |
| |
| if (is_syn) |
| { |
| tc = tcp_half_open_connection_get (index); |
| /* Note: the connection may have transitioned to ESTABLISHED... */ |
| if (PREDICT_FALSE (tc == 0)) |
| return; |
| tc->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID; |
| } |
| else |
| { |
| tc = tcp_connection_get (index, thread_index); |
| /* Note: the connection may have been closed and pool_put */ |
| if (PREDICT_FALSE (tc == 0)) |
| return; |
| tc->timers[TCP_TIMER_RETRANSMIT] = TCP_TIMER_HANDLE_INVALID; |
| } |
| |
| if (tc->state >= TCP_STATE_ESTABLISHED) |
| { |
| /* Lost FIN, retransmit and return */ |
| if (tcp_is_lost_fin (tc)) |
| { |
| tcp_send_fin (tc); |
| tc->rto_boff += 1; |
| tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX); |
| return; |
| } |
| |
| /* Shouldn't be here */ |
| if (seq_geq (tc->snd_una, tc->snd_congestion)) |
| { |
| tcp_recovery_off (tc); |
| return; |
| } |
| |
| /* We're not in recovery so make sure rto_boff is 0 */ |
| if (!tcp_in_recovery (tc) && tc->rto_boff > 0) |
| { |
| tc->rto_boff = 0; |
| tcp_update_rto (tc); |
| } |
| |
| /* Increment RTO backoff (also equal to number of retries) and go back |
| * to first un-acked byte */ |
| tc->rto_boff += 1; |
| |
| /* First retransmit timeout */ |
| if (tc->rto_boff == 1) |
| tcp_rtx_timeout_cc (tc); |
| |
| tc->snd_una_max = tc->snd_nxt = tc->snd_una; |
| tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX); |
| |
| TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 1); |
| |
| /* Send one segment. Note that n_bytes may be zero due to buffer shortfall */ |
| n_bytes = tcp_prepare_retransmit_segment (tc, 0, tc->snd_mss, &b); |
| |
| /* TODO be less aggressive about this */ |
| scoreboard_clear (&tc->sack_sb); |
| |
| if (n_bytes == 0) |
| { |
| tcp_retransmit_timer_set (tc); |
| return; |
| } |
| |
| bi = vlib_get_buffer_index (vm, b); |
| |
| /* For first retransmit, record timestamp (Eifel detection RFC3522) */ |
| if (tc->rto_boff == 1) |
| tc->snd_rxt_ts = tcp_time_now (); |
| |
| tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4); |
| tcp_retransmit_timer_update (tc); |
| } |
| /* Retransmit for SYN */ |
| else if (tc->state == TCP_STATE_SYN_SENT) |
| { |
| /* 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)) |
| { |
| clib_warning ("could not remove half-open connection"); |
| ASSERT (0); |
| } |
| 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); |
| |
| tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN, |
| tc->rto * TCP_TO_TIMER_TICK); |
| |
| if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi))) |
| return; |
| |
| b = vlib_get_buffer (vm, bi); |
| tcp_init_buffer (vm, b); |
| tcp_make_syn (tc, b); |
| |
| tc->rtt_ts = 0; |
| TCP_EVT_DBG (TCP_EVT_SYN_RXT, tc, 0); |
| |
| /* This goes straight to ipx_lookup. Retransmit timer set already */ |
| tcp_push_ip_hdr (tm, tc, b); |
| tcp_enqueue_to_ip_lookup (vm, b, bi, tc->c_is_ip4, tc->c_fib_index); |
| } |
| /* Retransmit SYN-ACK */ |
| else if (tc->state == TCP_STATE_SYN_RCVD) |
| { |
| tc->rto_boff += 1; |
| if (tc->rto_boff > TCP_RTO_SYN_RETRIES) |
| tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX); |
| tc->rtt_ts = 0; |
| |
| if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi))) |
| { |
| tcp_retransmit_timer_force_update (tc); |
| return; |
| } |
| |
| b = vlib_get_buffer (vm, bi); |
| tcp_init_buffer (vm, b); |
| tcp_make_synack (tc, b); |
| TCP_EVT_DBG (TCP_EVT_SYN_RXT, tc, 1); |
| |
| /* Retransmit timer already updated, just enqueue to output */ |
| tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4); |
| } |
| else |
| { |
| ASSERT (tc->state == TCP_STATE_CLOSED); |
| return; |
| } |
| } |
| |
| void |
| tcp_timer_retransmit_handler (u32 index) |
| { |
| tcp_timer_retransmit_handler_i (index, 0); |
| } |
| |
| void |
| tcp_timer_retransmit_syn_handler (u32 index) |
| { |
| tcp_timer_retransmit_handler_i (index, 1); |
| } |
| |
| /** |
| * Got 0 snd_wnd from peer, try to do something about it. |
| * |
| */ |
| void |
| tcp_timer_persist_handler (u32 index) |
| { |
| 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, max_snd_bytes, available_bytes, offset; |
| int n_bytes = 0; |
| u8 *data; |
| |
| tc = tcp_connection_get_if_valid (index, thread_index); |
| |
| if (!tc) |
| return; |
| |
| /* Make sure timer handle is set to invalid */ |
| tc->timers[TCP_TIMER_PERSIST] = TCP_TIMER_HANDLE_INVALID; |
| |
| /* Problem already solved or worse */ |
| if (tc->state == TCP_STATE_CLOSED || tc->state > TCP_STATE_ESTABLISHED |
| || tc->snd_wnd > tc->snd_mss || tcp_in_recovery (tc)) |
| return; |
| |
| available_bytes = stream_session_tx_fifo_max_dequeue (&tc->connection); |
| offset = tc->snd_una_max - 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) |
| { |
| ASSERT (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)); |
| return; |
| } |
| |
| /* 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 (tcp_get_free_buffer_index (tm, &bi))) |
| 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 - MAX_HDRS_LEN); |
| n_bytes = stream_session_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)); |
| |
| tcp_push_hdr_i (tc, b, tc->state, 0); |
| tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4); |
| |
| /* Just sent new data, enable retransmit */ |
| tcp_retransmit_timer_update (tc); |
| } |
| |
| /** |
| * Retransmit first unacked segment |
| */ |
| void |
| tcp_retransmit_first_unacked (tcp_connection_t * tc) |
| { |
| vlib_main_t *vm = vlib_get_main (); |
| vlib_buffer_t *b; |
| u32 bi, old_snd_nxt, n_bytes; |
| |
| old_snd_nxt = tc->snd_nxt; |
| tc->snd_nxt = tc->snd_una; |
| |
| TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 2); |
| n_bytes = tcp_prepare_retransmit_segment (tc, 0, tc->snd_mss, &b); |
| if (!n_bytes) |
| return; |
| bi = vlib_get_buffer_index (vm, b); |
| tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4); |
| |
| tc->snd_nxt = old_snd_nxt; |
| } |
| |
| /** |
| * Do fast retransmit with SACKs |
| */ |
| void |
| tcp_fast_retransmit_sack (tcp_connection_t * tc) |
| { |
| vlib_main_t *vm = vlib_get_main (); |
| u32 n_written = 0, offset, max_bytes; |
| vlib_buffer_t *b = 0; |
| sack_scoreboard_hole_t *hole; |
| sack_scoreboard_t *sb; |
| u32 bi, old_snd_nxt; |
| int snd_space; |
| u8 snd_limited = 0, can_rescue = 0; |
| |
| ASSERT (tcp_in_fastrecovery (tc)); |
| TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 0); |
| |
| old_snd_nxt = tc->snd_nxt; |
| sb = &tc->sack_sb; |
| snd_space = tcp_available_snd_space (tc); |
| |
| hole = scoreboard_get_hole (sb, sb->cur_rxt_hole); |
| while (hole && snd_space > 0) |
| { |
| hole = scoreboard_next_rxt_hole (sb, hole, |
| tcp_fastrecovery_sent_1_smss (tc), |
| &can_rescue, &snd_limited); |
| if (!hole) |
| { |
| if (!can_rescue || !(seq_lt (sb->rescue_rxt, tc->snd_una) |
| || seq_gt (sb->rescue_rxt, |
| tc->snd_congestion))) |
| 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. |
| */ |
| max_bytes = clib_min (tc->snd_mss, |
| tc->snd_congestion - tc->snd_una); |
| max_bytes = clib_min (max_bytes, snd_space); |
| offset = tc->snd_congestion - tc->snd_una - max_bytes; |
| sb->rescue_rxt = tc->snd_congestion; |
| tc->snd_nxt = tc->snd_una + offset; |
| n_written = tcp_prepare_retransmit_segment (tc, offset, max_bytes, |
| &b); |
| if (!n_written) |
| goto done; |
| |
| bi = vlib_get_buffer_index (vm, b); |
| tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4); |
| break; |
| } |
| |
| 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; |
| offset = sb->high_rxt - tc->snd_una; |
| tc->snd_nxt = sb->high_rxt; |
| n_written = tcp_prepare_retransmit_segment (tc, offset, max_bytes, &b); |
| |
| /* Nothing left to retransmit */ |
| if (n_written == 0) |
| break; |
| |
| bi = vlib_get_buffer_index (vm, b); |
| sb->high_rxt += n_written; |
| tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4); |
| ASSERT (n_written <= snd_space); |
| snd_space -= n_written; |
| } |
| |
| done: |
| /* If window allows, send 1 SMSS of new data */ |
| tc->snd_nxt = old_snd_nxt; |
| } |
| |
| /** |
| * Fast retransmit without SACK info |
| */ |
| void |
| tcp_fast_retransmit_no_sack (tcp_connection_t * tc) |
| { |
| vlib_main_t *vm = vlib_get_main (); |
| u32 n_written = 0, offset = 0, bi, old_snd_nxt; |
| int snd_space; |
| vlib_buffer_t *b; |
| |
| ASSERT (tcp_in_fastrecovery (tc)); |
| TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 0); |
| |
| /* Start resending from first un-acked segment */ |
| old_snd_nxt = tc->snd_nxt; |
| tc->snd_nxt = tc->snd_una; |
| snd_space = tcp_available_snd_space (tc); |
| |
| while (snd_space > 0) |
| { |
| offset += n_written; |
| n_written = tcp_prepare_retransmit_segment (tc, offset, snd_space, &b); |
| |
| /* Nothing left to retransmit */ |
| if (n_written == 0) |
| break; |
| |
| bi = vlib_get_buffer_index (vm, b); |
| tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4); |
| snd_space -= n_written; |
| } |
| |
| /* Restore snd_nxt. If window allows, send 1 SMSS of new data */ |
| tc->snd_nxt = old_snd_nxt; |
| } |
| |
| /** |
| * Do fast retransmit |
| */ |
| void |
| tcp_fast_retransmit (tcp_connection_t * tc) |
| { |
| if (tcp_opts_sack_permitted (&tc->rcv_opts) |
| && scoreboard_first_hole (&tc->sack_sb)) |
| tcp_fast_retransmit_sack (tc); |
| else |
| tcp_fast_retransmit_no_sack (tc); |
| } |
| |
| always_inline u32 |
| tcp_session_has_ooo_data (tcp_connection_t * tc) |
| { |
| stream_session_t *s = session_get (tc->c_s_index, tc->c_thread_index); |
| return svm_fifo_has_ooo_data (s->server_rx_fifo); |
| } |
| |
| static void |
| tcp_output_handle_link_local (tcp_connection_t * tc0, vlib_buffer_t * b0, |
| u32 * next0, u32 * error0) |
| { |
| 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; |
| } |
| |
| 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; |
| } |
| |
| always_inline uword |
| tcp46_output_inline (vlib_main_t * vm, |
| vlib_node_runtime_t * node, |
| vlib_frame_t * from_frame, int is_ip4) |
| { |
| 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; |
| next_index = node->cached_next_index; |
| tcp_set_time_now (my_thread_index); |
| |
| while (n_left_from > 0) |
| { |
| u32 n_left_to_next; |
| |
| vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); |
| |
| 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; |
| |
| if (n_left_from > 1) |
| { |
| vlib_buffer_t *pb; |
| pb = vlib_get_buffer (vm, from[1]); |
| vlib_prefetch_buffer_header (pb, STORE); |
| CLIB_PREFETCH (pb->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; |
| |
| 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; |
| } |
| |
| th0 = vlib_buffer_get_current (b0); |
| TCP_EVT_DBG (TCP_EVT_OUTPUT, tc0, th0->flags, b0->current_length); |
| vnet_buffer (b0)->sw_if_index[VLIB_TX] = tc0->c_fib_index; |
| vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0; |
| |
| if (is_ip4) |
| { |
| vlib_buffer_push_ip4 (vm, b0, &tc0->c_lcl_ip4, &tc0->c_rmt_ip4, |
| IP_PROTOCOL_TCP, 1); |
| b0->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM; |
| vnet_buffer (b0)->l4_hdr_offset = (u8 *) th0 - b0->data; |
| th0->checksum = 0; |
| } |
| else |
| { |
| ip6_header_t *ih0; |
| ih0 = vlib_buffer_push_ip6 (vm, b0, &tc0->c_lcl_ip6, |
| &tc0->c_rmt_ip6, IP_PROTOCOL_TCP); |
| b0->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM; |
| vnet_buffer (b0)->l3_hdr_offset = (u8 *) ih0 - b0->data; |
| vnet_buffer (b0)->l4_hdr_offset = (u8 *) th0 - b0->data; |
| th0->checksum = 0; |
| |
| if (PREDICT_FALSE |
| (ip6_address_is_link_local_unicast (&tc0->c_rmt_ip6))) |
| tcp_output_handle_link_local (tc0, b0, &next0, &error0); |
| } |
| |
| /* Filter out DUPACKs if there are no OOO segments left */ |
| if (PREDICT_FALSE |
| (vnet_buffer (b0)->tcp.flags & TCP_BUF_FLAG_DUPACK)) |
| { |
| /* N.B. Should not filter burst of dupacks. Two issues: |
| * 1) dupacks open cwnd on remote peer when congested |
| * 2) acks leaving should have the latest rcv_wnd since the |
| * burst may have eaten up all of it, so only the old ones |
| * could be filtered. |
| */ |
| if (!tcp_session_has_ooo_data (tc0)) |
| { |
| error0 = TCP_ERROR_FILTERED_DUPACKS; |
| next0 = TCP_OUTPUT_NEXT_DROP; |
| goto done; |
| } |
| } |
| |
| /* Stop DELACK timer and fix flags */ |
| tc0->flags &= ~(TCP_CONN_SNDACK); |
| tcp_timer_reset (tc0, TCP_TIMER_DELACK); |
| |
| /* 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)) |
| { |
| tc0->snd_una_max = tc0->snd_nxt; |
| if (tc0->rtt_ts == 0) |
| { |
| tc0->rtt_ts = tcp_time_now (); |
| tc0->rtt_seq = tc0->snd_nxt; |
| } |
| } |
| |
| /* 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; |
| } |
| |
| #if 0 |
| /* Make sure we haven't lost route to our peer */ |
| if (PREDICT_FALSE (tc0->last_fib_check |
| < tc0->snd_opts.tsval + TCP_FIB_RECHECK_PERIOD)) |
| { |
| if (PREDICT_TRUE |
| (tc0->c_rmt_fei == tcp_lookup_rmt_in_fib (tc0))) |
| { |
| tc0->last_fib_check = tc0->snd_opts.tsval; |
| } |
| else |
| { |
| clib_warning ("lost connection to peer"); |
| tcp_connection_reset (tc0); |
| goto done; |
| } |
| } |
| |
| /* Use pre-computed dpo to set next node */ |
| next0 = tc0->c_rmt_dpo.dpoi_next_node; |
| vnet_buffer (b0)->ip.adj_index[VLIB_TX] = tc0->c_rmt_dpo.dpoi_index; |
| #endif |
| |
| 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)); |
| } |
| |
| vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, |
| n_left_to_next, bi0, next0); |
| } |
| |
| vlib_put_next_frame (vm, node, next_index, n_left_to_next); |
| } |
| |
| return from_frame->n_vectors; |
| } |
| |
| static uword |
| tcp4_output (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) |
| { |
| return tcp46_output_inline (vm, node, from_frame, 0 /* is_ip4 */ ); |
| } |
| |
| /* *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 = { |
| #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n, |
| foreach_tcp4_output_next |
| #undef _ |
| }, |
| .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, |
| .error_strings = tcp_error_strings, |
| .n_next_nodes = TCP_OUTPUT_N_NEXT, |
| .next_nodes = { |
| #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n, |
| foreach_tcp6_output_next |
| #undef _ |
| }, |
| .format_buffer = format_tcp_header, |
| .format_trace = format_tcp_tx_trace, |
| }; |
| /* *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); |
| ASSERT (seq_leq (tc->snd_una_max, tc->snd_una + tc->snd_wnd)); |
| |
| if (tc->rtt_ts == 0 && !tcp_in_cong_recovery (tc)) |
| { |
| tc->rtt_ts = tcp_time_now (); |
| tc->rtt_seq = tc->snd_nxt; |
| } |
| tcp_trajectory_add_start (b, 3); |
| return 0; |
| } |
| |
| typedef enum _tcp_reset_next |
| { |
| TCP_RESET_NEXT_DROP, |
| TCP_RESET_NEXT_IP_LOOKUP, |
| TCP_RESET_N_NEXT |
| } tcp_reset_next_t; |
| |
| #define foreach_tcp4_reset_next \ |
| _(DROP, "error-drop") \ |
| _(IP_LOOKUP, "ip4-lookup") |
| |
| #define foreach_tcp6_reset_next \ |
| _(DROP, "error-drop") \ |
| _(IP_LOOKUP, "ip6-lookup") |
| |
| static uword |
| tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node, |
| vlib_frame_t * from_frame, u8 is_ip4) |
| { |
| 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; |
| |
| next_index = node->cached_next_index; |
| |
| while (n_left_from > 0) |
| { |
| u32 n_left_to_next; |
| |
| vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); |
| |
| 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; |
| |
| bi0 = from[0]; |
| to_next[0] = bi0; |
| from += 1; |
| to_next += 1; |
| n_left_from -= 1; |
| 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; |
| } |
| |
| /* Prepare to send to IP lookup */ |
| vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0; |
| next0 = TCP_RESET_NEXT_IP_LOOKUP; |
| |
| done: |
| b0->error = node->errors[error0]; |
| b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED; |
| if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED)) |
| { |
| th0 = vlib_buffer_get_current (b0); |
| if (is_ip4) |
| th0 = ip4_next_header ((ip4_header_t *) th0); |
| 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)); |
| } |
| |
| vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, |
| n_left_to_next, bi0, next0); |
| } |
| vlib_put_next_frame (vm, node, next_index, n_left_to_next); |
| } |
| return from_frame->n_vectors; |
| } |
| |
| static uword |
| tcp4_send_reset (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) |
| { |
| 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, |
| .error_strings = tcp_error_strings, |
| .n_next_nodes = TCP_RESET_N_NEXT, |
| .next_nodes = { |
| #define _(s,n) [TCP_RESET_NEXT_##s] = n, |
| foreach_tcp4_reset_next |
| #undef _ |
| }, |
| .format_trace = format_tcp_tx_trace, |
| }; |
| /* *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, |
| .error_strings = tcp_error_strings, |
| .n_next_nodes = TCP_RESET_N_NEXT, |
| .next_nodes = { |
| #define _(s,n) [TCP_RESET_NEXT_##s] = n, |
| foreach_tcp6_reset_next |
| #undef _ |
| }, |
| .format_trace = format_tcp_tx_trace, |
| }; |
| /* *INDENT-ON* */ |
| |
| VLIB_NODE_FUNCTION_MULTIARCH (tcp6_reset_node, tcp6_send_reset); |
| |
| /* |
| * fd.io coding-style-patch-verification: ON |
| * |
| * Local Variables: |
| * eval: (c-set-style "gnu") |
| * End: |
| */ |