X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=src%2Fvnet%2Ftcp%2Ftcp_output.c;h=bbcbc9121753fec498a5c028d0fd7b1c0f89b0cc;hb=371ca50a74a9c4f1b74c4c1b65c6fdec610fcfc3;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..bbcbc912175 100644 --- a/src/vnet/tcp/tcp_output.c +++ b/src/vnet/tcp/tcp_output.c @@ -15,11 +15,12 @@ #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, @@ -54,33 +55,54 @@ 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); + 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); + format_tcp_connection, &t->tcp_connection, 1); return s; } 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 + * 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) { - 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_MIN_RX_FIFO_SIZE; } /** @@ -136,10 +158,10 @@ tcp_update_rcv_wnd (tcp_connection_t * tc) * 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); + max_fifo = stream_session_rx_fifo_size (&tc->connection); - ASSERT (tc->opt.mss < max_fifo); - if (available_space < tc->opt.mss && available_space < max_fifo >> 3) + ASSERT (tc->rcv_opts.mss < max_fifo); + if (available_space < tc->rcv_opts.mss && available_space < max_fifo >> 3) available_space = 0; /* @@ -276,8 +298,11 @@ 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; @@ -293,14 +318,14 @@ 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 +333,7 @@ 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; @@ -326,14 +351,14 @@ tcp_make_established_options (tcp_connection_t * tc, tcp_options_t * opts) 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->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)) { @@ -364,24 +389,11 @@ tcp_make_options (tcp_connection_t * tc, tcp_options_t * opts, case TCP_STATE_SYN_SENT: return tcp_make_syn_options (opts, tc->rcv_wscale); default: - clib_warning ("Not handled!"); + clib_warning ("State not handled! %d", state); return 0; } } -/** - * 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; -} - /** * Update snd_mss to reflect the effective segment size that we can send * by taking into account all TCP options, including SACKs @@ -395,76 +407,109 @@ tcp_update_snd_mss (tcp_connection_t * tc) 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); } 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->opt.mss, tc->mss); + tc->snd_mss = clib_min (tc->rcv_opts.mss, tc->mss); - if (tc->snd_mss == 0) + if (tc->snd_mss < 45) { clib_warning ("snd mss is 0"); - tc->snd_mss = tc->mss; + /* 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->opt)) + if (tcp_opts_tstamp (&tc->rcv_opts)) 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) +always_inline int +tcp_alloc_tx_buffers (tcp_main_t * tm, u8 thread_index, u32 n_free_buffers) +{ + vlib_main_t *vm = vlib_get_main (); + u32 current_length = vec_len (tm->tx_buffers[thread_index]); + u32 n_allocated; + + vec_validate (tm->tx_buffers[thread_index], + current_length + n_free_buffers - 1); + n_allocated = + vlib_buffer_alloc (vm, &tm->tx_buffers[thread_index][current_length], + n_free_buffers); + _vec_len (tm->tx_buffers[thread_index]) = current_length + n_allocated; + /* buffer shortage, report failure */ + if (vec_len (tm->tx_buffers[thread_index]) == 0) + { + clib_warning ("out of buffers"); + return -1; + } + return 0; +} -always_inline void -tcp_reuse_buffer (vlib_main_t * vm, vlib_buffer_t * b) +always_inline int +tcp_get_free_buffer_index (tcp_main_t * tm, u32 * bidx) { - vlib_buffer_t *it = b; - do + u32 *my_tx_buffers; + u32 thread_index = vlib_get_thread_index (); + + TCP_DBG_BUFFER_ALLOC_MAYBE_FAIL (thread_index); + + if (PREDICT_FALSE (vec_len (tm->tx_buffers[thread_index]) == 0)) { - it->current_data = 0; - it->current_length = 0; - it->total_length_not_including_first_buffer = 0; + if (tcp_alloc_tx_buffers (tm, thread_index, VLIB_FRAME_SIZE)) + return -1; } - while ((it->flags & VLIB_BUFFER_NEXT_PRESENT) - && (it = vlib_get_buffer (vm, it->next_buffer))); + my_tx_buffers = tm->tx_buffers[thread_index]; + *bidx = my_tx_buffers[vec_len (my_tx_buffers) - 1]; + _vec_len (my_tx_buffers) -= 1; + return 0; +} + +always_inline void +tcp_return_buffer (tcp_main_t * tm) +{ + _vec_len (tm->tx_buffers[vlib_get_thread_index ()]) += 1; +} + +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 */ - vlib_buffer_make_headroom (b, MAX_HDRS_LEN); + 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; 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); } /** @@ -523,8 +568,31 @@ tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b) /* Reset flags, make sure ack is sent */ vnet_buffer (b)->tcp.flags &= ~TCP_BUF_FLAG_DUPACK; +} - tc->snd_nxt += 1; +/** + * 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); } /** @@ -538,113 +606,163 @@ tcp_make_synack (tcp_connection_t * tc, vlib_buffer_t * b) 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; - 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); + /* 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 (vlib_main_t * vm, vlib_buffer_t * b, u32 bi, - u8 is_ip4) +tcp_enqueue_to_ip_lookup_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_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] = ~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 = 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) +{ + tcp_enqueue_to_ip_lookup_i (vm, b, bi, is_ip4, 1); +} + +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 (vm, b, bi, is_ip4, 0); +} + +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); - /* Enqueue the packet */ + /* 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[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); + 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, u32 my_thread_index, u8 is_ip4) + tcp_state_t state, u8 thread_index, 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; + 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 */ - 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); - } + th0 = tcp_buffer_hdr (b0); - /* Swap src and dst ip */ + /* 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; - 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; + 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 (&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 (&dst_ip60, &ih6->dst_address, sizeof (ip6_address_t)); } - /* Try to determine what/why we're actually resetting and swap - * src and dst ports */ + 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)) @@ -653,33 +771,33 @@ tcp_make_reset_in_place (vlib_main_t * vm, vlib_buffer_t * b0, 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; - + flags = TCP_FLAG_RST | TCP_FLAG_ACK; + ack = clib_host_to_net_u32 (tmp + 1); + seq = 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_RST; + seq = th0->ack_number; + ack = 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, 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); - /* Compute checksum */ 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); } @@ -689,9 +807,11 @@ tcp_make_reset_in_place (vlib_main_t * vm, vlib_buffer_t * b0, /** * 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, u8 is_ip4) { vlib_buffer_t *b; u32 bi; @@ -703,11 +823,11 @@ tcp_send_reset (vlib_buffer_t * pkt, u8 is_ip4) ip4_header_t *ih4, *pkt_ih4; ip6_header_t *ih6, *pkt_ih6; - tcp_get_free_buffer_index (tm, &bi); - b = vlib_get_buffer (vm, bi); + if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi))) + return; - /* Leave enough space for headers */ - vlib_buffer_make_headroom (b, MAX_HDRS_LEN); + b = vlib_get_buffer (vm, bi); + tcp_init_buffer (vm, b); /* Make and write options */ tcp_hdr_len = sizeof (tcp_header_t); @@ -727,7 +847,7 @@ tcp_send_reset (vlib_buffer_t * pkt, u8 is_ip4) { flags = TCP_FLAG_RST; seq = pkt_th->ack_number; - ack = 0; + ack = (tc && tc->state >= TCP_STATE_SYN_RCVD) ? tc->rcv_nxt : 0; } else { @@ -744,46 +864,93 @@ 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, 1); 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 (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 (vm, b, bi, is_ip4); + tcp_enqueue_to_ip_lookup_now (vm, b, bi, is_ip4); + 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); + 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 (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); + 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 (tm->vlib_main, b, &tc->c_lcl_ip6, + 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 (tm->vlib_main, b, ih, - &bogus); + th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih, &bogus); ASSERT (!bogus); } } @@ -802,71 +969,76 @@ tcp_send_syn (tcp_connection_t * tc) 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_set (tc, TCP_TIMER_ESTABLISH, TCP_ESTABLISH_TIME); + 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 (tcp_get_free_buffer_index (tm, &bi))) + 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_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_EVT_DBG (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) +/** + * 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) { - u32 *to_next, next_index; - vlib_frame_t *f; - - b->flags |= VNET_BUFFER_LOCALLY_ORIGINATED; - b->error = 0; + 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; + } +} - /* Decide where to send the packet */ - next_index = is_ip4 ? tcp4_output_node.index : tcp6_output_node.index; +/** + * 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; + } +} - /* 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); +/** + * 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); } /** @@ -875,25 +1047,38 @@ 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) { - vlib_buffer_t *b; - u32 bi; 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_get_free_buffer_index (tm, &bi); + tcp_retransmit_timer_force_update (tc); + if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi))) + return; b = vlib_get_buffer (vm, bi); - - /* Leave enough space for headers */ - vlib_buffer_make_headroom (b, MAX_HDRS_LEN); - + 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 (vm, b, bi, tc->c_is_ip4); - tc->flags |= TCP_CONN_FINSNT; + 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_state_t next_state) +tcp_make_state_flags (tcp_connection_t * tc, tcp_state_t next_state) { switch (next_state) { @@ -905,7 +1090,10 @@ tcp_make_state_flags (tcp_state_t next_state) return TCP_FLAG_SYN; case TCP_STATE_LAST_ACK: case TCP_STATE_FIN_WAIT_1: - return TCP_FLAG_FIN; + 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!"); } @@ -924,42 +1112,40 @@ tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b, 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); - /* 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); + 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); - - /* 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; 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; - - if (tc->rtt_ts == 0) + if (seq_gt (tc->snd_nxt, tc->snd_una_max)) { - tc->rtt_ts = tcp_time_now (); - tc->rtt_seq = tc->snd_nxt; + 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); } @@ -973,7 +1159,8 @@ tcp_send_ack (tcp_connection_t * tc) u32 bi; /* Get buffer */ - tcp_get_free_buffer_index (tm, &bi); + if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi))) + return; b = vlib_get_buffer (vm, bi); /* Fill in the ACK */ @@ -981,7 +1168,11 @@ tcp_send_ack (tcp_connection_t * tc) tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4); } -/* Send delayed ACK when timer expires */ +/** + * Delayed ack timer handler + * + * Sends delayed ACK when timer expires + */ void tcp_timer_delack_handler (u32 index) { @@ -993,48 +1184,141 @@ tcp_timer_delack_handler (u32 index) tcp_send_ack (tc); } -/** Build a retransmit segment +/** + * 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) +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 (); - u32 n_bytes = 0; - - tcp_reuse_buffer (vm, b); + int n_bytes = 0; + u32 start, bi, available_bytes, seg_size; + u8 *data; ASSERT (tc->state >= TCP_STATE_ESTABLISHED); - ASSERT (max_bytes != 0); + ASSERT (max_deq_bytes != 0); - max_bytes = clib_min (tc->snd_mss, max_bytes); + /* + * 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 */ - if (seq_geq (tc->snd_una + offset, tc->snd_congestion)) + start = tc->snd_una + offset; + if (seq_geq (start, tc->snd_congestion)) goto done; /* Don't overshoot snd_congestion */ - if (seq_gt (tc->snd_nxt + max_bytes, tc->snd_congestion)) + if (seq_gt (start + max_deq_bytes, tc->snd_congestion)) { - max_bytes = tc->snd_congestion - tc->snd_nxt; - if (max_bytes == 0) + 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); - ASSERT (max_bytes <= tc->snd_mss); + /* + * Allocate and fill in buffer(s) + */ - 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 (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi))) + return 0; + *b = vlib_get_buffer (vm, bi); + data = tcp_init_buffer (vm, *b); + + /* Easy case, buffer size greater than mss */ + if (PREDICT_TRUE (seg_size <= tm->bytes_per_buffer)) + { + 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; + + n_bufs_per_seg = ceil ((double) seg_size / tm->bytes_per_buffer); + + /* Make sure we have enough buffers */ + available_bufs = vec_len (tm->tx_buffers[thread_index]); + if (n_bufs_per_seg > available_bufs) + { + if (tcp_alloc_tx_buffers (tm, thread_index, + VLIB_FRAME_SIZE - available_bufs)) + { + tcp_return_buffer (tm); + *b = 0; + return 0; + } + } + + 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->flags &= VLIB_BUFFER_NON_DEFAULT_FREELIST; + 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); @@ -1047,20 +1331,18 @@ done: 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_recover (tc); - } - else - { - tc->ssthresh = clib_max (tcp_flight_size (tc) / 2, 2 * tc->snd_mss); - } + tcp_cc_fastrecovery_exit (tc); /* Start again from the beginning */ - + tc->ssthresh = clib_max (tcp_flight_size (tc) / 2, 2 * tc->snd_mss); tc->cwnd = tcp_loss_wnd (tc); tc->snd_congestion = tc->snd_una_max; + tc->rtt_ts = 0; tcp_recovery_on (tc); } @@ -1071,91 +1353,149 @@ tcp_timer_retransmit_handler_i (u32 index, u8 is_syn) vlib_main_t *vm = vlib_get_main (); u32 thread_index = vlib_get_thread_index (); tcp_connection_t *tc; - vlib_buffer_t *b; + 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; } - /* Make sure timer handle is set to invalid */ - 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; + } - /* Increment RTO backoff (also equal to number of retries) */ - tc->rto_boff += 1; + /* Shouldn't be here */ + if (tc->snd_una == tc->snd_una_max) + { + tcp_recovery_off (tc); + return; + } - /* Go back to first un-acked byte */ - tc->snd_nxt = tc->snd_una; + /* 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); + } - /* Get buffer */ - tcp_get_free_buffer_index (tm, &bi); - b = vlib_get_buffer (vm, bi); + /* Increment RTO backoff (also equal to number of retries) and go back + * to first un-acked byte */ + tc->rto_boff += 1; - if (tc->state >= TCP_STATE_ESTABLISHED) - { /* First retransmit timeout */ if (tc->rto_boff == 1) tcp_rtx_timeout_cc (tc); - /* Exponential backoff */ + 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. No fancy recovery for now! */ - n_bytes = tcp_prepare_retransmit_segment (tc, b, 0, tc->snd_mss); + /* 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) { - clib_warning ("could not retransmit"); + 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); } - else + /* Retransmit for SYN */ + else if (tc->state == TCP_STATE_SYN_SENT) { - /* Retransmit for SYN/SYNACK */ - ASSERT (tc->state == TCP_STATE_SYN_RCVD - || 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); - vlib_buffer_make_headroom (b, MAX_HDRS_LEN); + tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN, + tc->rto * TCP_TO_TIMER_TICK); - tcp_push_hdr_i (tc, b, tc->state, 1); + if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi))) + return; - /* Account for the SYN */ - tc->snd_nxt += 1; - } + b = vlib_get_buffer (vm, bi); + tcp_init_buffer (vm, b); + tcp_make_syn (tc, b); - if (!is_syn) - { - tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4); + tc->rtt_ts = 0; + TCP_EVT_DBG (TCP_EVT_SYN_RXT, tc, 0); - /* Re-enable retransmit timer */ - tcp_retransmit_timer_set (tc); + /* 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); } - else + /* Retransmit SYN-ACK */ + else if (tc->state == TCP_STATE_SYN_RCVD) { - ASSERT (tc->state == TCP_STATE_SYN_SENT); + 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; - TCP_EVT_DBG (TCP_EVT_SYN_RTX, tc); + if (PREDICT_FALSE (tcp_get_free_buffer_index (tm, &bi))) + { + tcp_retransmit_timer_force_update (tc); + return; + } - /* 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); + b = vlib_get_buffer (vm, bi); + tcp_make_synack (tc, b); + TCP_EVT_DBG (TCP_EVT_SYN_RXT, tc, 1); - /* Re-enable retransmit timer */ - tcp_timer_set (tc, TCP_TIMER_RETRANSMIT_SYN, - tc->rto * TCP_TO_TIMER_TICK); + /* 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; } } @@ -1183,42 +1523,67 @@ tcp_timer_persist_handler (u32 index) u32 thread_index = vlib_get_thread_index (); tcp_connection_t *tc; vlib_buffer_t *b; - u32 bi, n_bytes; + u32 bi, max_snd_bytes, available_bytes, offset; + int n_bytes = 0; + u8 *data; - tc = tcp_connection_get (index, thread_index); + 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->snd_wnd > tc->snd_mss || tcp_in_recovery (tc)) + 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 */ - tcp_get_free_buffer_index (tm, &bi); + /* + * 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); - 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; - } + 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); - /* Re-enable persist timer */ - tcp_persist_timer_set (tc); + /* Just sent new data, enable retransmit */ + tcp_retransmit_timer_update (tc); } /** @@ -1227,113 +1592,154 @@ tcp_timer_persist_handler (u32 index) void tcp_retransmit_first_unacked (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, n_bytes; + u32 bi, old_snd_nxt, n_bytes; + old_snd_nxt = tc->snd_nxt; 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); - - n_bytes = tcp_prepare_retransmit_segment (tc, b, 0, tc->snd_mss); - if (n_bytes == 0) - goto done; - + 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); -done: - tc->snd_nxt = tc->snd_una_max; + tc->snd_nxt = old_snd_nxt; } -sack_scoreboard_hole_t * -scoreboard_first_rtx_hole (sack_scoreboard_t * sb) -{ - sack_scoreboard_hole_t *hole = 0; - -// 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; +/** + * 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); + ASSERT (n_written); + 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; + } + + /* If window allows, send 1 SMSS of new data */ + tc->snd_nxt = old_snd_nxt; } /** - * Do fast retransmit. + * Fast retransmit without SACK info */ void -tcp_fast_retransmit (tcp_connection_t * tc) +tcp_fast_retransmit_no_sack (tcp_connection_t * tc) { - tcp_main_t *tm = vnet_get_tcp_main (); vlib_main_t *vm = vlib_get_main (); - u32 bi; + u32 n_written = 0, offset = 0, bi, old_snd_nxt; int snd_space; - u32 n_written = 0, offset = 0; vlib_buffer_t *b; - u8 use_sacks = 0; 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); - TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 0); - - /* If we have SACKs use them */ - if (tcp_opts_sack_permitted (&tc->opt) - && scoreboard_first_hole (&tc->sack_sb)) - use_sacks = 0; while (snd_space > 0) { - tcp_get_free_buffer_index (tm, &bi); - b = vlib_get_buffer (vm, bi); - - if (use_sacks) - { - scoreboard_first_rtx_hole (&tc->sack_sb); - } - else - { - offset += n_written; - } - - n_written = tcp_prepare_retransmit_segment (tc, b, offset, snd_space); + offset += n_written; + n_written = tcp_prepare_retransmit_segment (tc, offset, snd_space, &b); /* Nothing left to retransmit */ if (n_written == 0) - { - tcp_return_buffer (tm); - break; - } + break; + bi = vlib_get_buffer_index (vm, b); 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; + /* 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 = - stream_session_get (tc->c_s_index, tc->c_thread_index); + stream_session_t *s = session_get (tc->c_s_index, tc->c_thread_index); return svm_fifo_has_ooo_data (s->server_rx_fifo); } @@ -1347,8 +1753,8 @@ tcp46_output_inline (vlib_main_t * vm, 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) { @@ -1387,21 +1793,21 @@ tcp46_output_inline (vlib_main_t * vm, if (is_ip4) { - 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); + 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; - 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); + 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; } /* Filter out DUPACKs if there are no OOO segments left */ @@ -1418,10 +1824,7 @@ tcp46_output_inline (vlib_main_t * vm, /* Stop DELACK timer and fix flags */ tc0->flags &= ~(TCP_CONN_SNDACK); - if (tcp_timer_is_active (tc0, TCP_TIMER_DELACK)) - { - tcp_timer_reset (tc0, TCP_TIMER_DELACK); - } + tcp_timer_reset (tc0, TCP_TIMER_DELACK); /* If not retransmitting * 1) update snd_una_max (SYN, SYNACK, FIN) @@ -1445,12 +1848,33 @@ tcp46_output_inline (vlib_main_t * vm, tc0->rto_boff = 0; } - /* set fib index to default and lookup node */ - /* XXX network virtualization (vrf/vni) */ +#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 + vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0; - vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0; + vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0; - b0->flags |= VNET_BUFFER_LOCALLY_ORIGINATED; + b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED; done: b0->error = node->errors[error0]; if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED)) @@ -1542,6 +1966,14 @@ tcp_push_header (transport_connection_t * tconn, vlib_buffer_t * b) 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; } @@ -1604,12 +2036,12 @@ tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node, } /* Prepare to send to IP lookup */ - vnet_buffer (b0)->sw_if_index[VLIB_TX] = 0; + 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_LOCALLY_ORIGINATED; + b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED; if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED)) { th0 = vlib_buffer_get_current (b0);