diff options
Diffstat (limited to 'plugins/vcgn-plugin/vcgn/cnat_ipv4_tcp_inside_input.c')
| -rw-r--r-- | plugins/vcgn-plugin/vcgn/cnat_ipv4_tcp_inside_input.c | 424 |
1 files changed, 424 insertions, 0 deletions
diff --git a/plugins/vcgn-plugin/vcgn/cnat_ipv4_tcp_inside_input.c b/plugins/vcgn-plugin/vcgn/cnat_ipv4_tcp_inside_input.c new file mode 100644 index 00000000000..5bea707385c --- /dev/null +++ b/plugins/vcgn-plugin/vcgn/cnat_ipv4_tcp_inside_input.c @@ -0,0 +1,424 @@ +/* + *--------------------------------------------------------------------------- + * cnat_ipv4_tcp_inside_input.c - cnat_ipv4_tcp_inside_input node pipeline + * stage functions + * + * + * Copyright (c) 2008-2014 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 <vlib/vlib.h> +#include <vnet/vnet.h> +#include <vppinfra/error.h> +#include <vnet/buffer.h> + +#include "cnat_db.h" +#include "tcp_header_definitions.h" +#include "cnat_config.h" +#include "cnat_global.h" +#include "cnat_v4_functions.h" + +#define foreach_cnat_ipv4_tcp_inside_input_error \ +_(CNAT_V4_TCP_I2O_PKT_IN, "tcp i2o packets received") \ +_(CNAT_V4_TCP_I2O_PKT_T, "tcp i2o packets natted") \ +_(CNAT_V4_TCP_I2O_EXCEPTION, "packets to tcp i2o exception") \ +_(CNAT_V4_TCP_I2O_TTL_GEN, "generated TTL expiry ICMP packets") \ +_(CNAT_V4_TCP_I2O_TTL_GEN_DROP, "could not generate TTL expiry ICMP packets") \ +_(CNAT_V4_TCP_I2O_SESSION_DROP, "could not generate session") \ +_(CNAT_V4_UDP_I2O_FRAG_DROP, "non-first fragment drop") + +typedef enum { +#define _(sym,str) sym, + foreach_cnat_ipv4_tcp_inside_input_error +#undef _ + CNAT_IPV4_TCP_INSIDE_INPUT_N_ERROR, +} cnat_ipv4_tcp_inside_input_t; + +static char * cnat_ipv4_tcp_inside_input_error_strings[] = { +#define _(sym,string) string, + foreach_cnat_ipv4_tcp_inside_input_error +#undef _ +}; + +typedef struct { + u32 cached_next_index; + /* $$$$ add data here */ + + /* convenience variables */ + vlib_main_t * vlib_main; + vnet_main_t * vnet_main; +} cnat_ipv4_tcp_inside_input_main_t; + +typedef enum { + CNAT_V4_TCP_I2O_E, + CNAT_V4_TCP_I2O_T, + CNAT_V4_TCP_I2O_D, + CNAT_V4_TCP_I2O_NEXT, +} cnat_ipv4_tcp_inside_input_next_t; + +#define CNAT_REWRITE_OUTPUT CNAT_V4_TCP_I2O_T +#define CNAT_V4_ICMP_GEN CNAT_V4_TCP_I2O_D + +//#define CNAT_V4_TCP_I2O_E CNAT_V4_TCP_I2O_D //remove it once exception node is created +cnat_ipv4_tcp_inside_input_main_t cnat_ipv4_tcp_inside_input_main; +vlib_node_registration_t cnat_ipv4_tcp_inside_input_node; + +#define NSTAGES 6 + +/* + * Use the generic buffer metadata + first line of packet data prefetch + * stage function from <api/pipeline.h>. This is usually a Good Idea. + */ +#define stage0 generic_stage0 + + +static inline void +stage1(vlib_main_t * vm, vlib_node_runtime_t * node, u32 buffer_index) +{ + u64 a, b, c; + u32 bucket; + u8 *prefetch_target; + //cnat_feature_data_t *fd = (cnat_feature_data_t *)ctx->feature_data; + + + vlib_buffer_t * b0 = vlib_get_buffer (vm, buffer_index); + ipv4_header *ip = vlib_buffer_get_current (b0); + u8 ipv4_hdr_len = (ip->version_hdr_len_words & 0xf) << 2; + tcp_hdr_type *tcp = (tcp_hdr_type *)((u8*)ip + ipv4_hdr_len); + + u64 tmp = 0; + tmp = vnet_buffer(b0)->vcgn_uii.key.k.ipv4 = + clib_net_to_host_u32(ip->src_addr); + vnet_buffer(b0)->vcgn_uii.key.k.port = + clib_net_to_host_u16 (tcp->src_port); + + tmp |= ((u64)vnet_buffer(b0)->vcgn_uii.key.k.port) << 32; + + PLATFORM_CNAT_SET_RX_VRF(vnet_buffer(b0)->sw_if_index[VLIB_RX], + vnet_buffer(b0)->vcgn_uii.key.k.vrf, + CNAT_TCP) + tmp |= ((u64)vnet_buffer(b0)->vcgn_uii.key.k.vrf) << 48; + + CNAT_V4_GET_HASH(tmp, bucket, CNAT_MAIN_HASH_MASK) + + prefetch_target = (u8 *)(&cnat_in2out_hash[bucket]); + vnet_buffer(b0)->vcgn_uii.bucket = bucket; + + /* Prefetch the hash bucket */ + CLIB_PREFETCH(prefetch_target, CLIB_CACHE_LINE_BYTES, LOAD); +} + +static inline void +stage2(vlib_main_t * vm, vlib_node_runtime_t * node, u32 buffer_index) +{ /* nothing */ } + + +#define SPP_LOG2_CACHE_LINE_BYTES 6 +#define SPP_CACHE_LINE_BYTES (1 << SPP_LOG2_CACHE_LINE_BYTES) + +static inline void +stage3(vlib_main_t * vm, vlib_node_runtime_t * node, u32 buffer_index) +{ + vlib_buffer_t * b0 = vlib_get_buffer(vm, buffer_index); + uword prefetch_target0, prefetch_target1; + u32 bucket = vnet_buffer(b0)->vcgn_uii.bucket; + + /* read the hash bucket */ + u32 db_index = vnet_buffer(b0)->vcgn_uii.bucket + = cnat_in2out_hash[bucket].next; + + if (PREDICT_TRUE(db_index != EMPTY)) { + /* + * Prefetch database keys. We save space by not cache-line + * aligning the DB entries. We don't want to waste LSU + * bandwidth prefetching stuff we won't need. + */ + prefetch_target0 = (uword)(cnat_main_db + db_index); + CLIB_PREFETCH((void*)prefetch_target0, CLIB_CACHE_LINE_BYTES, LOAD); + /* Just beyond DB key #2 */ + prefetch_target1 = prefetch_target0 + + STRUCT_OFFSET_OF(cnat_main_db_entry_t, user_ports); + /* If the targets are in different lines, do the second prefetch */ + if (PREDICT_FALSE((prefetch_target0 & ~(SPP_CACHE_LINE_BYTES-1)) != + (prefetch_target1 & ~(SPP_CACHE_LINE_BYTES-1)))) { + CLIB_PREFETCH((void *)prefetch_target1, CLIB_CACHE_LINE_BYTES, LOAD); + } + } +} + +static inline void +stage4(vlib_main_t * vm, vlib_node_runtime_t * node, u32 buffer_index) +{ + cnat_main_db_entry_t *db; + vlib_buffer_t * b0 = vlib_get_buffer(vm, buffer_index); + u32 db_index = vnet_buffer(b0)->vcgn_uii.bucket; + + /* + * Note: if the search already failed (empty bucket), + * the answer is already in the pipeline context structure + */ + if (PREDICT_TRUE(db_index != EMPTY)) { + + /* + * Note: hash collisions suck. We can't easily prefetch around them. + * The first trip around the track will be fast. After that, maybe + * not so much... + */ + do { + db = cnat_main_db + db_index; + if (PREDICT_TRUE(db->in2out_key.key64 == + vnet_buffer(b0)->vcgn_uii.key.key64)) { + break; + } + db_index = db->in2out_hash.next; + } while (db_index != EMPTY); + + /* Stick the answer back into the pipeline context structure */ + vnet_buffer(b0)->vcgn_uii.bucket = db_index; + } +} + + +static inline u32 last_stage (vlib_main_t *vm, vlib_node_runtime_t *node, + u32 bi) +{ + vlib_buffer_t *b0 = vlib_get_buffer (vm, bi); + u32 db_index = vnet_buffer(b0)->vcgn_uii.bucket; + spp_ctx_t *ctx = (spp_ctx_t *) &vnet_buffer(b0)->vcgn_uii; + int disposition = CNAT_V4_TCP_I2O_T; + int counter = CNAT_V4_TCP_I2O_PKT_T; + + ipv4_header *ip = (ipv4_header *)vlib_buffer_get_current(b0); + u8 ipv4_hdr_len = (ip->version_hdr_len_words & 0xf) << 2; + tcp_hdr_type *tcp = (tcp_hdr_type *)((u8*)ip + ipv4_hdr_len); + vlib_node_t *n = vlib_get_node (vm, cnat_ipv4_tcp_inside_input_node.index); + u32 node_counter_base_index = n->error_heap_index; + vlib_error_main_t * em = &vm->error_main; + cnat_session_entry_t *session_db = NULL; + cnat_main_db_entry_t *db = NULL; + cnat_key_t dest_info; + u32 window; + u8 scale; + + + INCREMENT_NODE_COUNTER(CNAT_V4_TCP_I2O_PKT_IN); + + if (PLATFORM_HANDLE_TTL_DECREMENT) { + if (PREDICT_FALSE(ip->ttl <= 1)) { + /* Try to generate ICMP error msg, as TTL is <= 1 */ + + if (icmpv4_generate_with_throttling + (ctx, ip, ctx->ru.rx.uidb_index)) { + + /* Generated ICMP */ + disposition = CNAT_REWRITE_OUTPUT; + counter = CNAT_V4_TCP_I2O_TTL_GEN; + } else { + /* Could not generated ICMP - drop the packet */ + disposition = CNAT_V4_TCP_I2O_D; + counter = CNAT_V4_TCP_I2O_TTL_GEN_DROP; + } + goto drop_pkt; + } + } + + if (PREDICT_FALSE(db_index == EMPTY)) { + /* Deleted fragment code from here */ + disposition = CNAT_V4_TCP_I2O_E; + counter = CNAT_V4_TCP_I2O_EXCEPTION; + } else { + db = cnat_main_db + db_index; + + /* Handle destination sessions */ + dest_info.k.port = clib_net_to_host_u16(tcp->dest_port); + dest_info.k.ipv4 = clib_net_to_host_u32(ip->dest_addr); + + if(PREDICT_TRUE(!PLATFORM_DBL_SUPPORT)) { + + /* No DBL support, so just update the destn and proceed */ + db->dst_ipv4 = dest_info.k.ipv4; + db->dst_port = dest_info.k.port; + goto update_pkt; + } + + if(PREDICT_FALSE(db->dst_ipv4 != dest_info.k.ipv4 || + db->dst_port != dest_info.k.port)) { + if(PREDICT_TRUE(db->nsessions == 0)) { + /* Should be a static entry + * Note this session as the first session and log + */ + cnat_add_dest_n_log(db, &dest_info); + } else if(PREDICT_FALSE(db->nsessions == 1)) { + /* Destn is not same as in main db. Multiple session + * scenario + */ + dest_info.k.vrf = db->in2out_key.k.vrf; + session_db = cnat_handle_1to2_session(db, &dest_info); + if(PREDICT_FALSE(session_db == NULL)) { + disposition = CNAT_V4_TCP_I2O_D; + counter = CNAT_V4_TCP_I2O_SESSION_DROP; + goto drop_pkt; + } + } else { /* There are already multiple destinations */ + dest_info.k.vrf = db->in2out_key.k.vrf; + /* If session already exists, + * cnat_create_session_db_entry will return the existing db + * else create a new db + * If could not create, return NULL + */ + session_db = cnat_create_session_db_entry(&dest_info, + db, TRUE); + if(PREDICT_FALSE(session_db == NULL)) { + disposition = CNAT_V4_TCP_I2O_D; + counter = CNAT_V4_TCP_I2O_SESSION_DROP; + goto drop_pkt; + } + } + if(PREDICT_TRUE(session_db != 0)) { + /* Have to repeat the window size check for new destinations */ + window = (u32)clib_net_to_host_u16(tcp->window_size); + window = window << session_db->scale; + if(PREDICT_TRUE(!session_db->window)) { + calculate_window_scale(tcp, &scale); + session_db->scale = scale; + session_db->window = window; + } else if (PREDICT_FALSE(session_db->window < + window)) { + /* Update the db entry with window option from packet */ + session_db->window = window; + } else { + /* Do nothing */ + } + session_db->tcp_seq_num = clib_net_to_host_u32(tcp->seq_num); + session_db->ack_no = clib_net_to_host_u32(tcp->ack_num); +#if DEBUG > 1 + printf("\n In2out SDB stages seq no = %u," + " ack no = %u, window = %u\n", + session_db->tcp_seq_num, + session_db->ack_no, + session_db->window); +#endif + + } + } else { + //Update the seq no and ack no for subsequent communication + //after connection establishment + //No need to update window here. Window is already updated + //during connection establishment + window = (u32)clib_net_to_host_u16(tcp->window_size); + window = window << db->scale; + if(PREDICT_FALSE(!ALG_ENABLED_DB(db))) { + //This check is done since proto_data is part of union in main + //db entry + db->proto_data.tcp_seq_chk.seq_no = + clib_net_to_host_u32(tcp->seq_num); + db->proto_data.tcp_seq_chk.ack_no = + clib_net_to_host_u32(tcp->ack_num); + } + if (PREDICT_FALSE(db->diff_window < window)) { + /* Update the db entry with window option from packet */ + db->diff_window = window; + } +#if DEBUG > 1 + printf("\n In2out MainDB seq no = %u," + "\n ack no = %u\n", + db->proto_data.tcp_seq_chk.seq_no, + db->proto_data.tcp_seq_chk.ack_no); + printf("\n In2out MAINDB window = %u\n", + db->diff_window); +#endif + } +update_pkt: + + counter = CNAT_V4_TCP_I2O_PKT_T; + disposition = CNAT_V4_TCP_I2O_T; + + /* NO FRAGMENT & ALG HANDLING. DELETING THE CODE */ + + if (PLATFORM_HANDLE_TTL_DECREMENT) { + /* + * Decrement TTL and update IPv4 checksum + */ + ipv4_decr_ttl_n_calc_csum(ip); + } + + tcp_in2out_nat_mss_n_checksum(ip, + tcp, + db->out2in_key.k.ipv4, + db->out2in_key.k.port, + db + /*, db->in2out_key.k.vrf */); + + /* update transaltion counters */ + db->in2out_pkts++; + in2out_forwarding_count++; + + /* update the timer for good mode, or evil mode dst_ip match */ + + if(PREDICT_FALSE(session_db != NULL)) { + V4_TCP_UPDATE_SESSION_DB_FLAG(session_db, tcp); + CNAT_DB_TIMEOUT_RST(session_db); + } else { + V4_TCP_UPDATE_SESSION_FLAG(db, tcp); + CNAT_DB_TIMEOUT_RST(db); + } + } + +drop_pkt: + + em->counters[node_counter_base_index + counter] += 1; + return disposition; +} + +#include <vnet/pipeline.h> + +static uword cnat_ipv4_tcp_inside_input_node_fn (vlib_main_t * vm, + vlib_node_runtime_t * node, + vlib_frame_t * frame) +{ + return dispatch_pipeline (vm, node, frame); +} + + +VLIB_REGISTER_NODE (cnat_ipv4_tcp_inside_input_node) = { + .function = cnat_ipv4_tcp_inside_input_node_fn, + .name = "vcgn-v4-tcp-i2o", + .vector_size = sizeof (u32), + .type = VLIB_NODE_TYPE_INTERNAL, + + .n_errors = ARRAY_LEN(cnat_ipv4_tcp_inside_input_error_strings), + .error_strings = cnat_ipv4_tcp_inside_input_error_strings, + + .n_next_nodes = CNAT_V4_TCP_I2O_NEXT, + + /* edit / add dispositions here */ + .next_nodes = { + [CNAT_V4_TCP_I2O_E] = "vcgn-v4-tcp-i2o-e", + [CNAT_V4_TCP_I2O_T] = "ip4-input", + [CNAT_V4_TCP_I2O_D] = "error-drop", + }, +}; + +clib_error_t *cnat_ipv4_tcp_inside_input_init (vlib_main_t *vm) +{ + cnat_ipv4_tcp_inside_input_main_t * mp = &cnat_ipv4_tcp_inside_input_main; + + mp->vlib_main = vm; + mp->vnet_main = vnet_get_main(); + + return 0; +} + +VLIB_INIT_FUNCTION (cnat_ipv4_tcp_inside_input_init); |