diff options
Diffstat (limited to 'src/plugins/ioam/ip6/ioam_cache_node.c')
| -rw-r--r-- | src/plugins/ioam/ip6/ioam_cache_node.c | 421 |
1 files changed, 421 insertions, 0 deletions
diff --git a/src/plugins/ioam/ip6/ioam_cache_node.c b/src/plugins/ioam/ip6/ioam_cache_node.c new file mode 100644 index 00000000..dd27e127 --- /dev/null +++ b/src/plugins/ioam/ip6/ioam_cache_node.c @@ -0,0 +1,421 @@ +/* + * Copyright (c) 2017 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. + */ +/* + * This file implements caching of ioam header and reattaching + * it in response message by performing request-response matching. + * Works for TCP SYN/SYN-ACK. + * This feature is used for anycast server selection. + * ioam data thus cached is used to measure and get complete round trip + * network path to help in server selection. + * There are 2 graph nodes defined to : + * 1. process packets that contain iOAM header and cache it + * 2. process TCP SYN-ACKs and reattach ioam header from the + * cache corresponding to TCP-SYN + * These graph nodes are attached to the vnet graph based on + * ioam cache and classifier configs. + * e.g. + * If db06::06 is the anycast service IP6 address: + * + * set ioam ip6 cache + * + * Apply this classifier on interface where requests for anycast service are received: + * classify session acl-hit-next ip6-node ip6-lookup table-index 0 match l3 ip6 dst db06::06 + * ioam-decap anycast <<< ioam-decap is hooked to cache when set ioam ip6 cache is enabled + * + * Apply this classifier on interface where responses from anycast service are received: + * classify session acl-hit-next ip6-node ip6-add-from-cache-hop-by-hop table-index 0 match l3 + * ip6 src db06::06 ioam-encap anycast-response + * + */ +#include <vlib/vlib.h> +#include <vnet/vnet.h> +#include <vnet/pg/pg.h> +#include <vppinfra/error.h> +#include <vnet/ip/ip.h> +#include <ioam/ip6/ioam_cache.h> +#include <vnet/ip/ip6_hop_by_hop.h> +#include <vnet/ip/ip6_hop_by_hop_packet.h> + +typedef struct +{ + u32 next_index; + u32 flow_label; +} cache_trace_t; + +/* packet trace format function */ +static u8 * +format_cache_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 *); + cache_trace_t *t = va_arg (*args, cache_trace_t *); + + s = format (s, "CACHE: flow_label %d, next index %d", + t->flow_label, t->next_index); + return s; +} + +#define foreach_cache_error \ +_(RECORDED, "ip6 iOAM headers cached") + +typedef enum +{ +#define _(sym,str) CACHE_ERROR_##sym, + foreach_cache_error +#undef _ + CACHE_N_ERROR, +} cache_error_t; + +static char *cache_error_strings[] = { +#define _(sym,string) string, + foreach_cache_error +#undef _ +}; + +typedef enum +{ + IOAM_CACHE_NEXT_POP_HBYH, + IOAM_CACHE_N_NEXT, +} cache_next_t; + +static uword +ip6_ioam_cache_node_fn (vlib_main_t * vm, + vlib_node_runtime_t * node, vlib_frame_t * frame) +{ + u32 n_left_from, *from, *to_next; + cache_next_t next_index; + u32 recorded = 0; + + from = vlib_frame_vector_args (frame); + n_left_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); + // TODO: Dual loop + while (n_left_from > 0 && n_left_to_next > 0) + { + u32 bi0; + vlib_buffer_t *p0; + u32 next0 = IOAM_CACHE_NEXT_POP_HBYH; + ip6_header_t *ip0; + ip6_hop_by_hop_header_t *hbh0; + tcp_header_t *tcp0; + u32 tcp_offset0; + + /* speculatively enqueue p0 to the current next frame */ + bi0 = from[0]; + to_next[0] = bi0; + from += 1; + to_next += 1; + n_left_from -= 1; + n_left_to_next -= 1; + + p0 = vlib_get_buffer (vm, bi0); + ip0 = vlib_buffer_get_current (p0); + if (IP_PROTOCOL_TCP == + ip6_locate_header (p0, ip0, IP_PROTOCOL_TCP, &tcp_offset0)) + { + tcp0 = (tcp_header_t *) ((u8 *) ip0 + tcp_offset0); + if ((tcp0->flags & TCP_FLAG_SYN) == TCP_FLAG_SYN && + (tcp0->flags & TCP_FLAG_ACK) == 0) + { + /* Cache the ioam hbh header */ + hbh0 = (ip6_hop_by_hop_header_t *) (ip0 + 1); + if (0 == ioam_cache_add (p0, + ip0, + clib_net_to_host_u16 + (tcp0->src_port), + clib_net_to_host_u16 + (tcp0->dst_port), hbh0, + clib_net_to_host_u32 + (tcp0->seq_number) + 1)) + { + recorded++; + } + } + } + if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE))) + { + if (p0->flags & VLIB_BUFFER_IS_TRACED) + { + cache_trace_t *t = + vlib_add_trace (vm, node, p0, sizeof (*t)); + t->flow_label = + clib_net_to_host_u32 + (ip0->ip_version_traffic_class_and_flow_label); + t->next_index = next0; + } + } + /* verify speculative enqueue, maybe switch current next frame */ + 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); + } + + vlib_node_increment_counter (vm, ioam_cache_node.index, + CACHE_ERROR_RECORDED, recorded); + return frame->n_vectors; +} + +/* + * Node for IP6 iOAM header cache + */ +/* *INDENT-OFF* */ +VLIB_REGISTER_NODE (ioam_cache_node) = +{ + .function = ip6_ioam_cache_node_fn, + .name = "ip6-ioam-cache", + .vector_size = sizeof (u32), + .format_trace = format_cache_trace, + .type = VLIB_NODE_TYPE_INTERNAL, + .n_errors = ARRAY_LEN (cache_error_strings), + .error_strings = cache_error_strings, + .n_next_nodes = IOAM_CACHE_N_NEXT, + /* edit / add dispositions here */ + .next_nodes = + { + [IOAM_CACHE_NEXT_POP_HBYH] = "ip6-pop-hop-by-hop" + }, +}; +/* *INDENT-ON* */ + +typedef struct +{ + u32 next_index; +} ip6_add_from_cache_hbh_trace_t; + +/* packet trace format function */ +static u8 * +format_ip6_add_from_cache_hbh_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 *); + ip6_add_from_cache_hbh_trace_t *t = va_arg (*args, + ip6_add_from_cache_hbh_trace_t + *); + + s = format (s, "IP6_ADD_FROM_CACHE_HBH: next index %d", t->next_index); + return s; +} + +vlib_node_registration_t ip6_add_from_cache_hbh_node; + +#define foreach_ip6_add_from_cache_hbh_error \ +_(PROCESSED, "Pkts w/ added ip6 hop-by-hop options") + +typedef enum +{ +#define _(sym,str) IP6_ADD_FROM_CACHE_HBH_ERROR_##sym, + foreach_ip6_add_from_cache_hbh_error +#undef _ + IP6_ADD_FROM_CACHE_HBH_N_ERROR, +} ip6_add_from_cache_hbh_error_t; + +static char *ip6_add_from_cache_hbh_error_strings[] = { +#define _(sym,string) string, + foreach_ip6_add_from_cache_hbh_error +#undef _ +}; + +#define foreach_ip6_ioam_cache_input_next \ + _(IP6_LOOKUP, "ip6-lookup") \ + _(DROP, "error-drop") + +typedef enum +{ +#define _(s,n) IP6_IOAM_CACHE_INPUT_NEXT_##s, + foreach_ip6_ioam_cache_input_next +#undef _ + IP6_IOAM_CACHE_INPUT_N_NEXT, +} ip6_ioam_cache_input_next_t; + + +static uword +ip6_add_from_cache_hbh_node_fn (vlib_main_t * vm, + vlib_node_runtime_t * node, + vlib_frame_t * frame) +{ + ioam_cache_main_t *cm = &ioam_cache_main; + u32 n_left_from, *from, *to_next; + ip_lookup_next_t next_index; + u32 processed = 0; + u8 *rewrite = 0; + u32 rewrite_len = 0; + u32 sr_rewrite_len = vec_len (cm->sr_rewrite_template); + + from = vlib_frame_vector_args (frame); + n_left_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); + // TODO: Dual loop + while (n_left_from > 0 && n_left_to_next > 0) + { + u32 bi0; + vlib_buffer_t *b0; + u32 next0; + ip6_header_t *ip0; + ip6_hop_by_hop_header_t *hbh0; + ip6_sr_header_t *srh0 = 0; + u64 *copy_src0, *copy_dst0; + u16 new_l0; + tcp_header_t *tcp0; + u32 tcp_offset0; + ioam_cache_entry_t *entry = 0; + + next0 = IP6_IOAM_CACHE_INPUT_NEXT_IP6_LOOKUP; + /* speculatively enqueue b0 to the current next frame */ + 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); + + ip0 = vlib_buffer_get_current (b0); + if (IP_PROTOCOL_TCP != + ip6_locate_header (b0, ip0, IP_PROTOCOL_TCP, &tcp_offset0)) + { + goto TRACE0; + } + tcp0 = (tcp_header_t *) ((u8 *) ip0 + tcp_offset0); + if (((tcp0->flags & TCP_FLAG_SYN) == TCP_FLAG_SYN && + (tcp0->flags & TCP_FLAG_ACK) == TCP_FLAG_ACK) || + (tcp0->flags & TCP_FLAG_RST) == TCP_FLAG_RST) + { + if (0 != (entry = ioam_cache_lookup (ip0, + clib_net_to_host_u16 + (tcp0->src_port), + clib_net_to_host_u16 + (tcp0->dst_port), + clib_net_to_host_u32 + (tcp0->ack_number)))) + { + rewrite = entry->ioam_rewrite_string; + rewrite_len = vec_len (rewrite); + } + else + { + next0 = IP6_IOAM_CACHE_INPUT_NEXT_DROP; + goto TRACE0; + } + } + else + goto TRACE0; + + + /* Copy the ip header left by the required amount */ + copy_dst0 = (u64 *) (((u8 *) ip0) - (rewrite_len + sr_rewrite_len)); + copy_src0 = (u64 *) ip0; + + copy_dst0[0] = copy_src0[0]; + copy_dst0[1] = copy_src0[1]; + copy_dst0[2] = copy_src0[2]; + copy_dst0[3] = copy_src0[3]; + copy_dst0[4] = copy_src0[4]; + vlib_buffer_advance (b0, -(word) (rewrite_len + sr_rewrite_len)); + ip0 = vlib_buffer_get_current (b0); + + hbh0 = (ip6_hop_by_hop_header_t *) (ip0 + 1); + srh0 = (ip6_sr_header_t *) ((u8 *) hbh0 + rewrite_len); + /* $$$ tune, rewrite_len is a multiple of 8 */ + clib_memcpy (hbh0, rewrite, rewrite_len); + clib_memcpy (srh0, cm->sr_rewrite_template, sr_rewrite_len); + /* Copy dst address into the DA slot in the segment list */ + clib_memcpy (srh0->segments, ip0->dst_address.as_u64, + sizeof (ip6_address_t)); + /* Rewrite the ip6 dst address with the first hop */ + clib_memcpy (ip0->dst_address.as_u64, entry->next_hop.as_u64, + sizeof (ip6_address_t)); + clib_memcpy (&srh0->segments[1], + (u8 *) hbh0 + entry->my_address_offset, + sizeof (ip6_address_t)); + ioam_cache_entry_free (entry); + + /* Patch the protocol chain, insert the h-b-h (type 0) header */ + srh0->protocol = ip0->protocol; + hbh0->protocol = IPPROTO_IPV6_ROUTE; + ip0->protocol = 0; + new_l0 = + clib_net_to_host_u16 (ip0->payload_length) + rewrite_len + + sr_rewrite_len; + ip0->payload_length = clib_host_to_net_u16 (new_l0); + processed++; + TRACE0: + if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) + && (b0->flags & VLIB_BUFFER_IS_TRACED))) + { + ip6_add_from_cache_hbh_trace_t *t = + vlib_add_trace (vm, node, b0, sizeof (*t)); + t->next_index = next0; + } + + /* verify speculative enqueue, maybe switch current next frame */ + 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); + } + + vlib_node_increment_counter (vm, ip6_add_from_cache_hbh_node.index, + IP6_ADD_FROM_CACHE_HBH_ERROR_PROCESSED, + processed); + return frame->n_vectors; +} +/* *INDENT-OFF* */ +VLIB_REGISTER_NODE (ip6_add_from_cache_hbh_node) = +{ + .function = ip6_add_from_cache_hbh_node_fn, + .name = "ip6-add-from-cache-hop-by-hop", + .vector_size = sizeof (u32), + .format_trace = format_ip6_add_from_cache_hbh_trace, + .type = VLIB_NODE_TYPE_INTERNAL, + .n_errors = ARRAY_LEN (ip6_add_from_cache_hbh_error_strings), + .error_strings = ip6_add_from_cache_hbh_error_strings, + /* See ip/lookup.h */ + .n_next_nodes = IP6_IOAM_CACHE_INPUT_N_NEXT, + .next_nodes = + { +#define _(s,n) [IP6_IOAM_CACHE_INPUT_NEXT_##s] = n, + foreach_ip6_ioam_cache_input_next +#undef _ + }, +}; +/* *INDENT-ON* */ + +VLIB_NODE_FUNCTION_MULTIARCH (ip6_add_from_cache_hbh_node, + ip6_add_from_cache_hbh_node_fn) +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |