/* *------------------------------------------------------------------ * af_packet.c - linux kernel packet interface * * 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 #include #include #include #include #include #include #include #include #include #define foreach_af_packet_input_error \ _(PARTIAL_PKT, "partial packet") typedef enum { #define _(f,s) AF_PACKET_INPUT_ERROR_##f, foreach_af_packet_input_error #undef _ AF_PACKET_INPUT_N_ERROR, } af_packet_input_error_t; static char *af_packet_input_error_strings[] = { #define _(n,s) s, foreach_af_packet_input_error #undef _ }; typedef struct { u32 next_index; u32 hw_if_index; int block; u32 pkt_num; void *block_start; block_desc_t bd; tpacket3_hdr_t tph; vnet_virtio_net_hdr_t vnet_hdr; } af_packet_input_trace_t; static u8 * format_af_packet_input_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 *); af_packet_input_trace_t *t = va_arg (*args, af_packet_input_trace_t *); u32 indent = format_get_indent (s); s = format (s, "af_packet: hw_if_index %d next-index %d", t->hw_if_index, t->next_index); s = format ( s, "\n%Ublock %u:\n%Uaddress %p version %u seq_num %lu pkt_num %u", format_white_space, indent + 2, t->block, format_white_space, indent + 4, t->block_start, t->bd.version, t->bd.hdr.bh1.seq_num, t->pkt_num); s = format (s, "\n%Utpacket3_hdr:\n%Ustatus 0x%x len %u snaplen %u mac %u net %u" "\n%Usec 0x%x nsec 0x%x vlan %U" #ifdef TP_STATUS_VLAN_TPID_VALID " vlan_tpid %u" #endif , format_white_space, indent + 2, format_white_space, indent + 4, t->tph.tp_status, t->tph.tp_len, t->tph.tp_snaplen, t->tph.tp_mac, t->tph.tp_net, format_white_space, indent + 4, t->tph.tp_sec, t->tph.tp_nsec, format_ethernet_vlan_tci, t->tph.hv1.tp_vlan_tci #ifdef TP_STATUS_VLAN_TPID_VALID , t->tph.hv1.tp_vlan_tpid #endif ); s = format (s, "\n%Uvnet-hdr:\n%Uflags 0x%02x gso_type 0x%02x hdr_len %u" "\n%Ugso_size %u csum_start %u csum_offset %u", format_white_space, indent + 2, format_white_space, indent + 4, t->vnet_hdr.flags, t->vnet_hdr.gso_type, t->vnet_hdr.hdr_len, format_white_space, indent + 4, t->vnet_hdr.gso_size, t->vnet_hdr.csum_start, t->vnet_hdr.csum_offset); return s; } always_inline void buffer_add_to_chain (vlib_buffer_t *b, vlib_buffer_t *first_b, vlib_buffer_t *prev_b, u32 bi) { /* update first buffer */ first_b->total_length_not_including_first_buffer += b->current_length; /* update previous buffer */ prev_b->next_buffer = bi; prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT; /* update current buffer */ b->next_buffer = ~0; } static_always_inline void fill_gso_offload (vlib_buffer_t *b, u32 gso_size, u8 l4_hdr_sz) { b->flags |= VNET_BUFFER_F_GSO; vnet_buffer2 (b)->gso_size = gso_size; vnet_buffer2 (b)->gso_l4_hdr_sz = l4_hdr_sz; } static_always_inline void fill_cksum_offload (vlib_buffer_t *b, u8 *l4_hdr_sz, u8 is_ip) { vnet_buffer_oflags_t oflags = 0; u16 l2hdr_sz = 0; u16 ethertype = 0; u8 l4_proto = 0; if (is_ip) { switch (b->data[0] & 0xf0) { case 0x40: ethertype = ETHERNET_TYPE_IP4; break; case 0x60: ethertype = ETHERNET_TYPE_IP6; break; } } else { ethernet_header_t *eth = vlib_buffer_get_current (b); ethertype = clib_net_to_host_u16 (eth->type); l2hdr_sz = sizeof (ethernet_header_t); if (ethernet_frame_is_tagged (ethertype)) { ethernet_vlan_header_t *vlan = (ethernet_vlan_header_t *) (eth + 1); ethertype = clib_net_to_host_u16 (vlan->type); l2hdr_sz += sizeof (*vlan); if (ethertype == ETHERNET_TYPE_VLAN) { vlan++; ethertype = clib_net_to_host_u16 (vlan->type); l2hdr_sz += sizeof (*vlan); } } } vnet_buffer (b)->l2_hdr_offset = 0; vnet_buffer (b)->l3_hdr_offset = l2hdr_sz; if (ethertype == ETHERNET_TYPE_IP4) { ip4_header_t *ip4 = (vlib_buffer_get_current (b) + l2hdr_sz); vnet_buffer (b)->l4_hdr_offset = l2hdr_sz + ip4_header_bytes (ip4); b->flags |= (VNET_BUFFER_F_IS_IP4 | VNET_BUFFER_F_L2_HDR_OFFSET_VALID | VNET_BUFFER_F_L3_HDR_OFFSET_VALID | VNET_BUFFER_F_L4_HDR_OFFSET_VALID); l4_proto = ip4->protocol; } else if (ethertype == ETHERNET_TYPE_IP6) { ip6_header_t *ip6 = (vlib_buffer_get_current (b) + l2hdr_sz); b->flags |= (VNET_BUFFER_F_IS_IP6 | VNET_BUFFER_F_L2_HDR_OFFSET_VALID | VNET_BUFFER_F_L3_HDR_OFFSET_VALID | VNET_BUFFER_F_L4_HDR_OFFSET_VALID); u16 ip6_hdr_len = sizeof (ip6_header_t); if (ip6_ext_hdr (ip6->protocol)) { ip6_ext_header_t *p = (void *) (ip6 + 1); ip6_hdr_len += ip6_ext_header_len (p); while (ip6_ext_hdr (p->next_hdr)) { ip6_hdr_len += ip6_ext_header_len (p); p = ip6_ext_next_header (p); } l4_proto = p->next_hdr; } else l4_proto = ip6->protocol; vnet_buffer (b)->l4_hdr_offset = l2hdr_sz + ip6_hdr_len; } if (l4_proto == IP_PROTOCOL_TCP) { oflags |= VNET_BUFFER_OFFLOAD_F_TCP_CKSUM; tcp_header_t *tcp = (tcp_header_t *) (vlib_buffer_get_current (b) + vnet_buffer (b)->l4_hdr_offset); *l4_hdr_sz = tcp_header_bytes (tcp); } else if (l4_proto == IP_PROTOCOL_UDP) { oflags |= VNET_BUFFER_OFFLOAD_F_UDP_CKSUM; *l4_hdr_sz = sizeof (udp_header_t); } if (oflags) vnet_buffer_offload_flags_set (b, oflags); } always_inline uword af_packet_device_input_fn (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame, af_packet_if_t *apif, u8 is_cksum_gso_enabled) { af_packet_main_t *apm = &af_packet_main; tpacket3_hdr_t *tph; u32 next_index; u32 n_free_bufs; u32 n_rx_packets = 0; u32 n_rx_bytes = 0; u32 *to_next = 0; u32 block = apif->next_rx_block; u32 block_nr = apif->rx_req->tp_block_nr; u8 *block_start = 0; uword n_trace = vlib_get_trace_count (vm, node); u32 thread_index = vm->thread_index; u32 n_buffer_bytes = vlib_buffer_get_default_data_size (vm); u32 min_bufs = apif->rx_req->tp_frame_size / n_buffer_bytes; u32 num_pkts = 0; u32 rx_frame_offset = 0; block_desc_t *bd = 0; vlib_buffer_t bt; u8 is_ip = (apif->mode == AF_PACKET_IF_MODE_IP); if (is_ip) next_index = VNET_DEVICE_INPUT_NEXT_IP4_INPUT; else { next_index = VNET_DEVICE_INPUT_NEXT_ETHERNET_INPUT; if (PREDICT_FALSE (apif->per_interface_next_index != ~0)) next_index = apif->per_interface_next_index; /* redirect if feature path enabled */ vnet_feature_start_device_input_x1 (apif->sw_if_index, &next_index, &bt); } while ((((block_desc_t *) (block_start = apif->rx_ring[block])) ->hdr.bh1.block_status & TP_STATUS_USER) != 0) { u32 n_required = 0; if (PREDICT_FALSE (num_pkts == 0)) { bd = (block_desc_t *) block_start; num_pkts = bd->hdr.bh1.num_pkts; rx_frame_offset = sizeof (block_desc_t); } n_required = clib_max (num_pkts, VLIB_FRAME_SIZE); n_free_bufs = vec_len (apm->rx_buffers[thread_index]); if (PREDICT_FALSE (n_free_bufs < n_required)) { vec_validate (apm->rx_buffers[thread_index], n_required + n_free_bufs - 1); n_free_bufs += vlib_buffer_alloc ( vm, &apm->rx_buffers[thread_index][n_free_bufs], n_required); _vec_len (apm->rx_buffers[thread_index]) = n_free_bufs; } while (num_pkts && (n_free_bufs > min_bufs)) { u32 next0 = next_index; u32 n_left_to_next; vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); while (num_pkts && n_left_to_next && (n_free_bufs > min_bufs)) { tph = (tpacket3_hdr_t *) (block_start + rx_frame_offset); if (num_pkts > 1) CLIB_PREFETCH (block_start + rx_frame_offset + tph->tp_next_offset, 2 * CLIB_CACHE_LINE_BYTES, LOAD); vlib_buffer_t *b0 = 0, *first_b0 = 0, *prev_b0 = 0; vnet_virtio_net_hdr_t *vnet_hdr = 0; u32 data_len = tph->tp_snaplen; u32 offset = 0; u32 bi0 = ~0, first_bi0 = ~0; u8 l4_hdr_sz = 0; if (is_cksum_gso_enabled) vnet_hdr = (vnet_virtio_net_hdr_t *) ((u8 *) tph + tph->tp_mac - sizeof (vnet_virtio_net_hdr_t)); if (PREDICT_FALSE (((data_len / n_buffer_bytes) + 1) > vec_len (apm->rx_buffers[thread_index]))) { vec_validate (apm->rx_buffers[thread_index], VLIB_FRAME_SIZE + n_free_bufs - 1); n_free_bufs += vlib_buffer_alloc ( vm, &apm->rx_buffers[thread_index][n_free_bufs], VLIB_FRAME_SIZE); _vec_len (apm->rx_buffers[thread_index]) = n_free_bufs; } while (data_len) { /* grab free buffer */ u32 last_empty_buffer = vec_len (apm->rx_buffers[thread_index]) - 1; bi0 = apm->rx_buffers[thread_index][last_empty_buffer]; _vec_len (apm->rx_buffers[thread_index]) = last_empty_buffer; n_free_bufs--; /* copy data */ u32 bytes_to_copy = data_len > n_buffer_bytes ? n_buffer_bytes : data_len; u32 vlan_len = 0; u32 bytes_copied = 0; b0 = vlib_get_buffer (vm, bi0); b0->current_data = 0; /* Kernel removes VLAN headers, so reconstruct VLAN */ if (PREDICT_FALSE (tph->tp_status & TP_STATUS_VLAN_VALID)) { if (PREDICT_TRUE (offset == 0)) { clib_memcpy_fast (vlib_buffer_get_current (b0), (u8 *) tph + tph->tp_mac, sizeof (ethernet_header_t)); ethernet_header_t *eth = vlib_buffer_get_current (b0); ethernet_vlan_header_t *vlan = (ethernet_vlan_header_t *) (eth + 1); vlan->priority_cfi_and_id = clib_host_to_net_u16 (tph->hv1.tp_vlan_tci); vlan->type = eth->type; eth->type = clib_host_to_net_u16 (ETHERNET_TYPE_VLAN); vlan_len = sizeof (ethernet_vlan_header_t); bytes_copied = sizeof (ethernet_header_t); } } clib_memcpy_fast (((u8 *) vlib_buffer_get_current (b0)) + bytes_copied + vlan_len, (u8 *) tph + tph->tp_mac + offset + bytes_copied, (bytes_to_copy - bytes_copied)); /* fill buffer header */ b0->current_length = bytes_to_copy + vlan_len; if (offset == 0) { b0->total_length_not_including_first_buffer = 0; b0->flags = VLIB_BUFFER_TOTAL_LENGTH_VALID; vnet_buffer (b0)->sw_if_index[VLIB_RX] = apif->sw_if_index; vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~0; first_b0 = b0; first_bi0 = bi0; if (is_cksum_gso_enabled) { if (vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) fill_cksum_offload (first_b0, &l4_hdr_sz, is_ip); if (vnet_hdr->gso_type & (VIRTIO_NET_HDR_GSO_TCPV4 | VIRTIO_NET_HDR_GSO_TCPV6)) fill_gso_offload (first_b0, vnet_hdr->gso_size, l4_hdr_sz); } } else buffer_add_to_chain (b0, first_b0, prev_b0, bi0); prev_b0 = b0; offset += bytes_to_copy; data_len -= bytes_to_copy; } n_rx_packets++; n_rx_bytes += tph->tp_snaplen; to_next[0] = first_bi0; to_next += 1; n_left_to_next--; /* drop partial packets */ if (PREDICT_FALSE (tph->tp_len != tph->tp_snaplen)) { next0 = VNET_DEVICE_INPUT_NEXT_DROP; first_b0->error = node->errors[AF_PACKET_INPUT_ERROR_PARTIAL_PKT]; } else { if (PREDICT_FALSE (apif->mode == AF_PACKET_IF_MODE_IP)) { switch (first_b0->data[0] & 0xf0) { case 0x40: next0 = VNET_DEVICE_INPUT_NEXT_IP4_INPUT; break; case 0x60: next0 = VNET_DEVICE_INPUT_NEXT_IP6_INPUT; break; default: next0 = VNET_DEVICE_INPUT_NEXT_DROP; break; } if (PREDICT_FALSE (apif->per_interface_next_index != ~0)) next0 = apif->per_interface_next_index; } else { /* copy feature arc data from template */ first_b0->current_config_index = bt.current_config_index; vnet_buffer (first_b0)->feature_arc_index = vnet_buffer (&bt)->feature_arc_index; } } /* trace */ if (PREDICT_FALSE (n_trace > 0 && vlib_trace_buffer (vm, node, next0, first_b0, /* follow_chain */ 0))) { af_packet_input_trace_t *tr; vlib_set_trace_count (vm, node, --n_trace); tr = vlib_add_trace (vm, node, first_b0, sizeof (*tr)); tr->next_index = next0; tr->hw_if_index = apif->hw_if_index; tr->block = block; tr->block_start = bd; tr->pkt_num = bd->hdr.bh1.num_pkts - num_pkts; clib_memcpy_fast (&tr->bd, bd, sizeof (block_desc_t)); clib_memcpy_fast (&tr->tph, tph, sizeof (tpacket3_hdr_t)); if (is_cksum_gso_enabled) clib_memcpy_fast (&tr->vnet_hdr, vnet_hdr, sizeof (vnet_virtio_net_hdr_t)); else clib_memset_u8 (&tr->vnet_hdr, 0, sizeof (vnet_virtio_net_hdr_t)); } /* enque and take next packet */ vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, n_left_to_next, first_bi0, next0); /* next packet */ num_pkts--; rx_frame_offset += tph->tp_next_offset; } vlib_put_next_frame (vm, node, next_index, n_left_to_next); } if (PREDICT_TRUE (num_pkts == 0)) { bd->hdr.bh1.block_status = TP_STATUS_KERNEL; block = (block + 1) % block_nr; } } apif->next_rx_block = block; vlib_increment_combined_counter (vnet_get_main ()->interface_main.combined_sw_if_counters + VNET_INTERFACE_COUNTER_RX, vlib_get_thread_index (), apif->hw_if_index, n_rx_packets, n_rx_bytes); vnet_device_increment_rx_packets (thread_index, n_rx_packets); return n_rx_packets; } VLIB_NODE_FN (af_packet_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { u32 n_rx_packets = 0; af_packet_main_t *apm = &af_packet_main; vnet_hw_if_rxq_poll_vector_t *pv; pv = vnet_hw_if_get_rxq_poll_vector (vm, node); for (int i = 0; i < vec_len (pv); i++) { af_packet_if_t *apif; apif = vec_elt_at_index (apm->interfaces, pv[i].dev_instance); if (apif->is_admin_up) { if (apif->is_cksum_gso_enabled) n_rx_packets += af_packet_device_input_fn (vm, node, frame, apif, 1); else n_rx_packets += af_packet_device_input_fn (vm, node, frame, apif, 0); } } return n_rx_packets; } VLIB_REGISTER_NODE (af_packet_input_node) = { .name = "af-packet-input", .flags = VLIB_NODE_FLAG_TRACE_SUPPORTED, .sibling_of = "device-input", .format_trace = format_af_packet_input_trace, .type = VLIB_NODE_TYPE_INPUT, .state = VLIB_NODE_STATE_INTERRUPT, .n_errors = AF_PACKET_INPUT_N_ERROR, .error_strings = af_packet_input_error_strings, }; /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */