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Diffstat (limited to 'src/vnet/ip/ip4_input.c')
| -rw-r--r-- | src/vnet/ip/ip4_input.c | 507 |
1 files changed, 507 insertions, 0 deletions
diff --git a/src/vnet/ip/ip4_input.c b/src/vnet/ip/ip4_input.c new file mode 100644 index 00000000000..1cf5e0b8517 --- /dev/null +++ b/src/vnet/ip/ip4_input.c @@ -0,0 +1,507 @@ +/* + * Copyright (c) 2015 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. + */ +/* + * ip/ip4_input.c: IP v4 input node + * + * Copyright (c) 2008 Eliot Dresselhaus + * + * Permission is hereby granted, free of charge, to any person obtaining + * a copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE + * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION + * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION + * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ + +#include <vnet/ip/ip.h> +#include <vnet/ethernet/ethernet.h> +#include <vnet/ppp/ppp.h> +#include <vnet/hdlc/hdlc.h> + +typedef struct +{ + u8 packet_data[64]; +} ip4_input_trace_t; + +static u8 * +format_ip4_input_trace (u8 * s, va_list * va) +{ + CLIB_UNUSED (vlib_main_t * vm) = va_arg (*va, vlib_main_t *); + CLIB_UNUSED (vlib_node_t * node) = va_arg (*va, vlib_node_t *); + ip4_input_trace_t *t = va_arg (*va, ip4_input_trace_t *); + + s = format (s, "%U", + format_ip4_header, t->packet_data, sizeof (t->packet_data)); + + return s; +} + +typedef enum +{ + IP4_INPUT_NEXT_DROP, + IP4_INPUT_NEXT_PUNT, + IP4_INPUT_NEXT_LOOKUP, + IP4_INPUT_NEXT_LOOKUP_MULTICAST, + IP4_INPUT_NEXT_ICMP_ERROR, + IP4_INPUT_N_NEXT, +} ip4_input_next_t; + +/* Validate IP v4 packets and pass them either to forwarding code + or drop/punt exception packets. */ +always_inline uword +ip4_input_inline (vlib_main_t * vm, + vlib_node_runtime_t * node, + vlib_frame_t * frame, int verify_checksum) +{ + ip4_main_t *im = &ip4_main; + vnet_main_t *vnm = vnet_get_main (); + ip_lookup_main_t *lm = &im->lookup_main; + u32 n_left_from, *from, *to_next; + ip4_input_next_t next_index; + vlib_node_runtime_t *error_node = + vlib_node_get_runtime (vm, ip4_input_node.index); + vlib_simple_counter_main_t *cm; + u32 cpu_index = os_get_cpu_number (); + + from = vlib_frame_vector_args (frame); + n_left_from = frame->n_vectors; + next_index = node->cached_next_index; + + if (node->flags & VLIB_NODE_FLAG_TRACE) + vlib_trace_frame_buffers_only (vm, node, from, frame->n_vectors, + /* stride */ 1, + sizeof (ip4_input_trace_t)); + + cm = vec_elt_at_index (vnm->interface_main.sw_if_counters, + VNET_INTERFACE_COUNTER_IP4); + + 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 >= 4 && n_left_to_next >= 2) + { + vlib_buffer_t *p0, *p1; + ip4_header_t *ip0, *ip1; + u32 sw_if_index0, pi0, ip_len0, cur_len0, next0; + u32 sw_if_index1, pi1, ip_len1, cur_len1, next1; + i32 len_diff0, len_diff1; + u8 error0, error1, arc0, arc1; + + /* Prefetch next iteration. */ + { + vlib_buffer_t *p2, *p3; + + p2 = vlib_get_buffer (vm, from[2]); + p3 = vlib_get_buffer (vm, from[3]); + + vlib_prefetch_buffer_header (p2, LOAD); + vlib_prefetch_buffer_header (p3, LOAD); + + CLIB_PREFETCH (p2->data, sizeof (ip0[0]), LOAD); + CLIB_PREFETCH (p3->data, sizeof (ip1[0]), LOAD); + } + + to_next[0] = pi0 = from[0]; + to_next[1] = pi1 = from[1]; + from += 2; + to_next += 2; + n_left_from -= 2; + n_left_to_next -= 2; + + p0 = vlib_get_buffer (vm, pi0); + p1 = vlib_get_buffer (vm, pi1); + + ip0 = vlib_buffer_get_current (p0); + ip1 = vlib_buffer_get_current (p1); + + sw_if_index0 = vnet_buffer (p0)->sw_if_index[VLIB_RX]; + sw_if_index1 = vnet_buffer (p1)->sw_if_index[VLIB_RX]; + + error0 = error1 = IP4_ERROR_NONE; + + if (PREDICT_FALSE (ip4_address_is_multicast (&ip0->dst_address))) + { + arc0 = lm->mcast_feature_arc_index; + next0 = IP4_INPUT_NEXT_LOOKUP_MULTICAST; + } + else + { + arc0 = lm->ucast_feature_arc_index; + next0 = IP4_INPUT_NEXT_LOOKUP; + if (PREDICT_FALSE (ip0->ttl < 1)) + error0 = IP4_ERROR_TIME_EXPIRED; + } + + if (PREDICT_FALSE (ip4_address_is_multicast (&ip1->dst_address))) + { + arc1 = lm->mcast_feature_arc_index; + next1 = IP4_INPUT_NEXT_LOOKUP_MULTICAST; + } + else + { + arc1 = lm->ucast_feature_arc_index; + next1 = IP4_INPUT_NEXT_LOOKUP; + if (PREDICT_FALSE (ip1->ttl < 1)) + error1 = IP4_ERROR_TIME_EXPIRED; + } + + vnet_buffer (p0)->ip.adj_index[VLIB_RX] = ~0; + vnet_buffer (p1)->ip.adj_index[VLIB_RX] = ~0; + + vnet_feature_arc_start (arc0, sw_if_index0, &next0, p0); + vnet_feature_arc_start (arc1, sw_if_index1, &next1, p1); + + vlib_increment_simple_counter (cm, cpu_index, sw_if_index0, 1); + vlib_increment_simple_counter (cm, cpu_index, sw_if_index1, 1); + + /* Punt packets with options or wrong version. */ + if (PREDICT_FALSE (ip0->ip_version_and_header_length != 0x45)) + error0 = (ip0->ip_version_and_header_length & 0xf) != 5 ? + IP4_ERROR_OPTIONS : IP4_ERROR_VERSION; + + if (PREDICT_FALSE (ip1->ip_version_and_header_length != 0x45)) + error1 = (ip1->ip_version_and_header_length & 0xf) != 5 ? + IP4_ERROR_OPTIONS : IP4_ERROR_VERSION; + + /* Verify header checksum. */ + if (verify_checksum) + { + ip_csum_t sum0, sum1; + + ip4_partial_header_checksum_x1 (ip0, sum0); + ip4_partial_header_checksum_x1 (ip1, sum1); + + error0 = 0xffff != ip_csum_fold (sum0) ? + IP4_ERROR_BAD_CHECKSUM : error0; + error1 = 0xffff != ip_csum_fold (sum1) ? + IP4_ERROR_BAD_CHECKSUM : error1; + } + + /* Drop fragmentation offset 1 packets. */ + error0 = ip4_get_fragment_offset (ip0) == 1 ? + IP4_ERROR_FRAGMENT_OFFSET_ONE : error0; + error1 = ip4_get_fragment_offset (ip1) == 1 ? + IP4_ERROR_FRAGMENT_OFFSET_ONE : error1; + + /* Verify lengths. */ + ip_len0 = clib_net_to_host_u16 (ip0->length); + ip_len1 = clib_net_to_host_u16 (ip1->length); + + /* IP length must be at least minimal IP header. */ + error0 = ip_len0 < sizeof (ip0[0]) ? IP4_ERROR_TOO_SHORT : error0; + error1 = ip_len1 < sizeof (ip1[0]) ? IP4_ERROR_TOO_SHORT : error1; + + cur_len0 = vlib_buffer_length_in_chain (vm, p0); + cur_len1 = vlib_buffer_length_in_chain (vm, p1); + + len_diff0 = cur_len0 - ip_len0; + len_diff1 = cur_len1 - ip_len1; + + error0 = len_diff0 < 0 ? IP4_ERROR_BAD_LENGTH : error0; + error1 = len_diff1 < 0 ? IP4_ERROR_BAD_LENGTH : error1; + + p0->error = error_node->errors[error0]; + p1->error = error_node->errors[error1]; + + if (PREDICT_FALSE (error0 != IP4_ERROR_NONE)) + { + if (error0 == IP4_ERROR_TIME_EXPIRED) + { + icmp4_error_set_vnet_buffer (p0, ICMP4_time_exceeded, + ICMP4_time_exceeded_ttl_exceeded_in_transit, + 0); + next0 = IP4_INPUT_NEXT_ICMP_ERROR; + } + else + next0 = error0 != IP4_ERROR_OPTIONS ? + IP4_INPUT_NEXT_DROP : IP4_INPUT_NEXT_PUNT; + } + if (PREDICT_FALSE (error1 != IP4_ERROR_NONE)) + { + if (error1 == IP4_ERROR_TIME_EXPIRED) + { + icmp4_error_set_vnet_buffer (p1, ICMP4_time_exceeded, + ICMP4_time_exceeded_ttl_exceeded_in_transit, + 0); + next1 = IP4_INPUT_NEXT_ICMP_ERROR; + } + else + next1 = error1 != IP4_ERROR_OPTIONS ? + IP4_INPUT_NEXT_DROP : IP4_INPUT_NEXT_PUNT; + } + + vlib_validate_buffer_enqueue_x2 (vm, node, next_index, + to_next, n_left_to_next, + pi0, pi1, next0, next1); + } + while (n_left_from > 0 && n_left_to_next > 0) + { + vlib_buffer_t *p0; + ip4_header_t *ip0; + u32 sw_if_index0, pi0, ip_len0, cur_len0, next0; + i32 len_diff0; + u8 error0, arc0; + + pi0 = from[0]; + to_next[0] = pi0; + from += 1; + to_next += 1; + n_left_from -= 1; + n_left_to_next -= 1; + + p0 = vlib_get_buffer (vm, pi0); + ip0 = vlib_buffer_get_current (p0); + + sw_if_index0 = vnet_buffer (p0)->sw_if_index[VLIB_RX]; + + error0 = IP4_ERROR_NONE; + + if (PREDICT_FALSE (ip4_address_is_multicast (&ip0->dst_address))) + { + arc0 = lm->mcast_feature_arc_index; + next0 = IP4_INPUT_NEXT_LOOKUP_MULTICAST; + } + else + { + arc0 = lm->ucast_feature_arc_index; + next0 = IP4_INPUT_NEXT_LOOKUP; + if (PREDICT_FALSE (ip0->ttl < 1)) + error0 = IP4_ERROR_TIME_EXPIRED; + } + + vnet_buffer (p0)->ip.adj_index[VLIB_RX] = ~0; + vnet_feature_arc_start (arc0, sw_if_index0, &next0, p0); + + vlib_increment_simple_counter (cm, cpu_index, sw_if_index0, 1); + + /* Punt packets with options or wrong version. */ + if (PREDICT_FALSE (ip0->ip_version_and_header_length != 0x45)) + error0 = (ip0->ip_version_and_header_length & 0xf) != 5 ? + IP4_ERROR_OPTIONS : IP4_ERROR_VERSION; + + /* Verify header checksum. */ + if (verify_checksum) + { + ip_csum_t sum0; + + ip4_partial_header_checksum_x1 (ip0, sum0); + error0 = + 0xffff != + ip_csum_fold (sum0) ? IP4_ERROR_BAD_CHECKSUM : error0; + } + + /* Drop fragmentation offset 1 packets. */ + error0 = + ip4_get_fragment_offset (ip0) == + 1 ? IP4_ERROR_FRAGMENT_OFFSET_ONE : error0; + + /* Verify lengths. */ + ip_len0 = clib_net_to_host_u16 (ip0->length); + + /* IP length must be at least minimal IP header. */ + error0 = ip_len0 < sizeof (ip0[0]) ? IP4_ERROR_TOO_SHORT : error0; + + cur_len0 = vlib_buffer_length_in_chain (vm, p0); + len_diff0 = cur_len0 - ip_len0; + error0 = len_diff0 < 0 ? IP4_ERROR_BAD_LENGTH : error0; + + p0->error = error_node->errors[error0]; + if (PREDICT_FALSE (error0 != IP4_ERROR_NONE)) + { + if (error0 == IP4_ERROR_TIME_EXPIRED) + { + icmp4_error_set_vnet_buffer (p0, ICMP4_time_exceeded, + ICMP4_time_exceeded_ttl_exceeded_in_transit, + 0); + next0 = IP4_INPUT_NEXT_ICMP_ERROR; + } + else + next0 = error0 != IP4_ERROR_OPTIONS ? + IP4_INPUT_NEXT_DROP : IP4_INPUT_NEXT_PUNT; + } + + vlib_validate_buffer_enqueue_x1 (vm, node, next_index, + to_next, n_left_to_next, + pi0, next0); + } + + vlib_put_next_frame (vm, node, next_index, n_left_to_next); + } + + return frame->n_vectors; +} + +/** \brief IPv4 input node. + @node ip4-input + + This is the IPv4 input node: validates ip4 header checksums, + verifies ip header lengths, discards pkts with expired TTLs, + and sends pkts to the set of ip feature nodes configured on + the rx interface. + + @param vm vlib_main_t corresponding to the current thread + @param node vlib_node_runtime_t + @param frame vlib_frame_t whose contents should be dispatched + + @par Graph mechanics: buffer metadata, next index usage + + @em Uses: + - vnet_feature_config_main_t cm corresponding to each pkt's dst address unicast / + multicast status. + - <code>b->current_config_index</code> corresponding to each pkt's + rx sw_if_index. + - This sets the per-packet graph trajectory, ensuring that + each packet visits the per-interface features in order. + + - <code>vnet_buffer(b)->sw_if_index[VLIB_RX]</code> + - Indicates the @c sw_if_index value of the interface that the + packet was received on. + + @em Sets: + - <code>vnet_buffer(b)->ip.adj_index[VLIB_TX]</code> + - The lookup result adjacency index. + + <em>Next Indices:</em> + - Dispatches pkts to the (first) feature node: + <code> vnet_get_config_data (... &next0 ...); </code> + or @c error-drop +*/ +static uword +ip4_input (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) +{ + return ip4_input_inline (vm, node, frame, /* verify_checksum */ 1); +} + +static uword +ip4_input_no_checksum (vlib_main_t * vm, + vlib_node_runtime_t * node, vlib_frame_t * frame) +{ + return ip4_input_inline (vm, node, frame, /* verify_checksum */ 0); +} + +static char *ip4_error_strings[] = { +#define _(sym,string) string, + foreach_ip4_error +#undef _ +}; + +/* *INDENT-OFF* */ +VLIB_REGISTER_NODE (ip4_input_node) = { + .function = ip4_input, + .name = "ip4-input", + .vector_size = sizeof (u32), + + .n_errors = IP4_N_ERROR, + .error_strings = ip4_error_strings, + + .n_next_nodes = IP4_INPUT_N_NEXT, + .next_nodes = { + [IP4_INPUT_NEXT_DROP] = "error-drop", + [IP4_INPUT_NEXT_PUNT] = "error-punt", + [IP4_INPUT_NEXT_LOOKUP] = "ip4-lookup", + [IP4_INPUT_NEXT_LOOKUP_MULTICAST] = "ip4-lookup-multicast", + [IP4_INPUT_NEXT_ICMP_ERROR] = "ip4-icmp-error", + }, + + .format_buffer = format_ip4_header, + .format_trace = format_ip4_input_trace, +}; +/* *INDENT-ON* */ + +VLIB_NODE_FUNCTION_MULTIARCH (ip4_input_node, ip4_input); + +/* *INDENT-OFF* */ +VLIB_REGISTER_NODE (ip4_input_no_checksum_node,static) = { + .function = ip4_input_no_checksum, + .name = "ip4-input-no-checksum", + .vector_size = sizeof (u32), + + .n_next_nodes = IP4_INPUT_N_NEXT, + .next_nodes = { + [IP4_INPUT_NEXT_DROP] = "error-drop", + [IP4_INPUT_NEXT_PUNT] = "error-punt", + [IP4_INPUT_NEXT_LOOKUP] = "ip4-lookup", + [IP4_INPUT_NEXT_LOOKUP_MULTICAST] = "ip4-lookup-multicast", + [IP4_INPUT_NEXT_ICMP_ERROR] = "ip4-icmp-error", + }, + + .format_buffer = format_ip4_header, + .format_trace = format_ip4_input_trace, +}; +/* *INDENT-ON* */ + +VLIB_NODE_FUNCTION_MULTIARCH (ip4_input_no_checksum_node, + ip4_input_no_checksum); + +static clib_error_t * +ip4_init (vlib_main_t * vm) +{ + clib_error_t *error; + + ethernet_register_input_type (vm, ETHERNET_TYPE_IP4, ip4_input_node.index); + ppp_register_input_protocol (vm, PPP_PROTOCOL_ip4, ip4_input_node.index); + hdlc_register_input_protocol (vm, HDLC_PROTOCOL_ip4, ip4_input_node.index); + + { + pg_node_t *pn; + pn = pg_get_node (ip4_input_node.index); + pn->unformat_edit = unformat_pg_ip4_header; + pn = pg_get_node (ip4_input_no_checksum_node.index); + pn->unformat_edit = unformat_pg_ip4_header; + } + + if ((error = vlib_call_init_function (vm, ip4_cli_init))) + return error; + + if ((error = vlib_call_init_function (vm, ip4_source_check_init))) + return error; + + if ((error = vlib_call_init_function + (vm, ip4_source_and_port_range_check_init))) + return error; + + /* Set flow hash to something non-zero. */ + ip4_main.flow_hash_seed = 0xdeadbeef; + + /* Default TTL for packets we generate. */ + ip4_main.host_config.ttl = 64; + + return error; +} + +VLIB_INIT_FUNCTION (ip4_init); + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |