diff options
Diffstat (limited to 'vpp/plugins/vcgn-plugin/vcgn/cnat_v4_functions.c')
| -rw-r--r-- | vpp/plugins/vcgn-plugin/vcgn/cnat_v4_functions.c | 364 |
1 files changed, 364 insertions, 0 deletions
diff --git a/vpp/plugins/vcgn-plugin/vcgn/cnat_v4_functions.c b/vpp/plugins/vcgn-plugin/vcgn/cnat_v4_functions.c new file mode 100644 index 00000000..d3051fba --- /dev/null +++ b/vpp/plugins/vcgn-plugin/vcgn/cnat_v4_functions.c @@ -0,0 +1,364 @@ +/* + *--------------------------------------------------------------------------- + * cnat_v4_funtions.c + * + * Copyright (c) 2008-2013 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 <vnet/pg/pg.h> +#include <vppinfra/error.h> + + +#include "tcp_header_definitions.h" +#include "cnat_db.h" +#include "cnat_config.h" +#include "cnat_v4_functions.h" +#include "dslite_defs.h" +#include "dslite_db.h" + +static u32 tcp_logging_count; +static u32 tcp_logging_overflow; + +static tcp_logging_struct_t tcp_logging_array[MAX_TCP_LOGGING_COUNT]; + +/* + * Function to log TCP pkts checksum changes.. + */ +void +tcp_debug_logging ( + u32 seq_num, + u32 ack_num, + u32 old_ip, + u32 new_ip, + u16 old_port, + u16 new_port, + u16 old_ip_crc, + u16 new_ip_crc, + u16 old_tcp_crc, + u16 new_tcp_crc) +{ + tcp_logging_array[tcp_logging_count].seq_num = seq_num; + tcp_logging_array[tcp_logging_count].ack_num = ack_num; + tcp_logging_array[tcp_logging_count].old_ip = old_ip; + tcp_logging_array[tcp_logging_count].new_ip = new_ip; + tcp_logging_array[tcp_logging_count].old_port = old_port; + tcp_logging_array[tcp_logging_count].new_port = new_port; + tcp_logging_array[tcp_logging_count].old_ip_crc = old_ip_crc; + tcp_logging_array[tcp_logging_count].new_ip_crc = new_ip_crc; + tcp_logging_array[tcp_logging_count].old_tcp_crc = old_tcp_crc; + tcp_logging_array[tcp_logging_count].new_tcp_crc = new_tcp_crc; + + tcp_logging_count++; + + if (tcp_logging_count >= MAX_TCP_LOGGING_COUNT) { + tcp_logging_overflow = 1; + tcp_logging_count = 0; + } +} + +/* + * Function to dmp TCP pkts logged.. + */ +void +tcp_debug_logging_dump (void) +{ + u32 i, total_count, start_entry; + + if (tcp_logging_overflow) { + total_count = MAX_TCP_LOGGING_COUNT; + start_entry = tcp_logging_count; + printf("Logging Entries Wrapped Around, displaying %d entries\n", + total_count); + } else { + total_count = tcp_logging_count; + start_entry = 0; + printf("Displaying %d entries\n", total_count); + } + + printf("SEQ ACK IP_O IP_N PORT_O PORT_N L3_CRC_O L3_CRC_N L4_CRC_O L4_CRC_N\n"); + + for (i = 0; i < total_count; i++) { + u32 entry = (i + start_entry) % MAX_TCP_LOGGING_COUNT; + + printf("%04d: 0x%08x 0x%08x 0x%08x 0x%08x 0x%04x 0x%04x 0x%04x 0x%04x 0x%04x 0x%04x\n", + entry, + tcp_logging_array[entry].seq_num, + tcp_logging_array[entry].ack_num, + tcp_logging_array[entry].old_ip, + tcp_logging_array[entry].new_ip, + tcp_logging_array[entry].old_port, + tcp_logging_array[entry].new_port, + tcp_logging_array[entry].old_ip_crc, + tcp_logging_array[entry].new_ip_crc, + tcp_logging_array[entry].old_tcp_crc, + tcp_logging_array[entry].new_tcp_crc); + } +} + +/* + * Function to enable TCP logging + */ +void +tcp_debug_logging_enable_disable (u32 enable_flag) +{ + switch (enable_flag) { + + case TCP_LOGGING_DISABLE: + if (tcp_logging_enable_flag == TCP_LOGGING_DISABLE) { + printf("\nTCP Logging ALREADY DISABLED\n"); + } else { + printf("\nTCP Logging DISABLED\n"); + } + tcp_logging_enable_flag = 0; + break; + + case TCP_LOGGING_ENABLE: + if (tcp_logging_enable_flag == TCP_LOGGING_ENABLE) { + printf("\nTCP Logging ALREADY ENABLED\n"); + } else { + tcp_logging_enable_flag = 1; + tcp_logging_count = 0; + tcp_logging_overflow = 0; + + printf("\nTCP Logging ENABLED\n"); + } + break; + + case TCP_LOGGING_PACKET_DUMP: + tcp_debug_logging_dump(); + break; + + case TCP_LOGGING_SUMMARY_DUMP: + default: + printf("\ntcp_logging_enable_flag %d, tcp_log_count %d\n", + tcp_logging_enable_flag, tcp_logging_count); + printf("To Enable TCP LOGGING provide a flag value of %d\n", + TCP_LOGGING_ENABLE); + break; + } +} + +void hex_dump (u8 * p, int len) { + int i; + for (i=0;i<len;i++) { + if(i && (i & 0x3 ) == 0) printf(" "); + if(i && (i & 0xf ) == 0) printf("\n"); + PLATFORM_DEBUG_PRINT("%02X ", p[i]); + } + PLATFORM_DEBUG_PRINT("\n"); +} + +void +print_icmp_pkt (ipv4_header *ip) +{ + u32 i, total_len; + + u8 *pkt = (u8 *) ip; + + total_len = clib_net_to_host_u16(ip->total_len_bytes); + + printf("\n======== PRINTING PKT START======\n"); + printf("======== IP PACKET LEN %d ===========\n", total_len); + for (i=0; i < 20; i++) { + printf(" %02X ", *(pkt + i)); + } + + printf("\n======== ICMP HEADER =================\n"); + for (i=20; i < 28; i++) { + printf(" %02X ", *(pkt + i)); + } + + printf("\n======== ICMP BODY ===================\n"); + for (i=28; i < total_len; i++) { + printf(" %02X ", *(pkt + i)); + } + + printf("\n======== PRINTING PKT END =======\n"); +} + +void +print_udp_pkt (ipv4_header *ip) +{ + u32 i, total_len, udp_len; + + u8 *pkt = (u8 *) ip; + + total_len = clib_net_to_host_u16(ip->total_len_bytes); + udp_len = total_len - 20; + + printf("\n======== PRINTING PKT START======\n"); + printf("======== IP PACKET LEN %d ===========\n", total_len); + for (i=0; i < 20; i++) { + printf(" %02X ", *(pkt + i)); + } + printf("\n======== UDP PSEUDO HEADER ==========\n"); + for (i=12; i < 20; i++) { + printf(" %02X ", *(pkt + i)); + } + printf(" 00 11 %02X %02X ", udp_len >> 8, udp_len & 0xff); + + printf("\n======== UDP HEADER =================\n"); + for (i=20; i < 28; i++) { + printf(" %02X ", *(pkt + i)); + } + printf("\n======== UDP BODY ===================\n"); + for (i=28; i < total_len; i++) { + printf(" %02X ", *(pkt + i)); + } + + printf("\n======== PRINTING PKT END =======\n"); +} + +void +print_tcp_pkt (ipv4_header *ip) +{ + u32 i, total_len, tcp_len; + + u8 *pkt = (u8 *) ip; + + total_len = clib_net_to_host_u16(ip->total_len_bytes); + tcp_len = total_len - 20; + + printf("\n======== PRINTING PKT START======\n"); + printf("======== IP PACKET LEN %d ===========\n", total_len); + for (i=0; i < 20; i++) { + printf(" %02X ", *(pkt + i)); + } + printf("\n======== TCP PSEUDO HEADER ==========\n"); + for (i=12; i < 20; i++) { + printf(" %02X ", *(pkt + i)); + } + printf(" 00 06 %02X %02X ", tcp_len >> 8, tcp_len & 0xff); + + printf("\n======== TCP HEADER =================\n"); + for (i=20; i < 40; i++) { + printf(" %02X ", *(pkt + i)); + } + printf("\n======== TCP BODY ===================\n"); + for (i=40; i < total_len; i++) { + printf(" %02X ", *(pkt + i)); + } + + printf("\n======== PRINTING PKT END =======\n"); +} + +/* IN: ipv4 and tcp header pointer, + * new ipv4 addr and port value + * main db index for accessing per vrf mss value + * DO: + * NAT + * mss adjust if needed + * ip & tcp checksum update (incremental) + */ + +inline void tcp_in2out_nat_mss_n_checksum (ipv4_header * ip, + tcp_hdr_type * tcp, + u32 ipv4_addr, + u16 port, + cnat_main_db_entry_t * db) +{ + u8 *mss_ptr; + u8 check_mss = 0; + u16 mss_old, mss_new; + cnat_vrfmap_t * vrf_map_p; + + cnat_v4_recalculate_tcp_checksum(ip, + tcp, + &(ip->src_addr), + &(tcp->src_port), + ipv4_addr, + port); + u16 frag_offset = + clib_net_to_host_u16(ip->frag_flags_offset); + + if(PREDICT_FALSE(frag_offset & IP_FRAG_OFFSET_MASK)) { + return; /* No TCP Header at all */ + } + + /* + * check SYN bit and if options field is present + * If yes, proceed to extract the options and get TCP MSS value + */ + check_mss = ((tcp->flags & TCP_FLAG_SYN) && + (((tcp->hdr_len>>4) << 2) > sizeof(tcp_hdr_type))); + + if (PREDICT_FALSE(check_mss)) { + + /* get per VRF mss config */ + if(PREDICT_FALSE(db->flags & (CNAT_DB_DSLITE_FLAG))) { + mss_new = dslite_table_db_ptr[db->dslite_nat44_inst_id].tcp_mss; + } else { + vrf_map_p = cnat_map_by_vrf + db->vrfmap_index; + mss_new = vrf_map_p->tcp_mss; + } + DSLITE_PRINTF(1, "Check MSS true..%u\n", mss_new); + /* + * If TCP MSS is not configured, skip the MSS checks + */ + if (PREDICT_FALSE(mss_new != V4_TCP_MSS_NOT_CONFIGURED_VALUE)) { + + /* if mss_ptr != NULL, then it points to MSS option */ + mss_ptr = tcp_findoption(tcp, TCP_OPTION_MSS); + + /* + * TCP option field: | kind 1B | len 1B | value 2B| + * where kind != [0,1] + */ + if (PREDICT_TRUE(mss_ptr && (mss_ptr[1] == 4))) { + + u16 *ptr = (u16*)(mss_ptr + 2); + + mss_old = clib_net_to_host_u16(*ptr); + + if (PREDICT_FALSE(mss_old > mss_new)) { + u32 sum32; + u16 mss_old_r, old_tcp_checksum_r; + + *ptr = clib_host_to_net_u16(mss_new); + + mss_old_r = ~mss_old; + + old_tcp_checksum_r = + ~clib_net_to_host_u16(tcp->tcp_checksum); + + /* + * Revise the TCP checksum + */ + sum32 = old_tcp_checksum_r + mss_old_r + mss_new; + FILL_CHECKSUM(tcp->tcp_checksum, sum32) + + if (PREDICT_FALSE(tcp_logging_enable_flag)) { + tcp_debug_logging( + clib_net_to_host_u32(tcp->seq_num), + clib_net_to_host_u32(tcp->ack_num), + 0, + 0, + mss_old, + mss_new, + 0, + 0, + ~old_tcp_checksum_r, + clib_net_to_host_u16(tcp->tcp_checksum)); + } + } + } + } + } +} + +u32 get_my_svi_intf_ip_addr() { + return 0x01010101; +} |