/*
*------------------------------------------------------------------
* cnat_v4_functions.h
*
* Copyright (c) 2007-2013 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.
*------------------------------------------------------------------
*/
#ifndef __CNAT_V4_FUNCTOINS__
#define __CNAT_V4_FUNCTOINS__
#include "tcp_header_definitions.h"
#include "cnat_db.h"
#include "spp_ctx.h"
#include "platform_common.h"
/*
* Defines and structures to enable TCP packet logging
*/
#define TCP_LOGGING_DISABLE 0
#define TCP_LOGGING_ENABLE 1
#define TCP_LOGGING_PACKET_DUMP 2
#define TCP_LOGGING_SUMMARY_DUMP 3
#define MAX_TCP_LOGGING_COUNT 1024
typedef struct tcp_logging_struct {
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_struct_t;
void tcp_debug_logging_dump (void);
void tcp_debug_logging_enable_disable (u32 enable_flag);
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);
#define JLI printf("%s %s %d\n", __FILE__, __FUNCTION__, __LINE__); fflush(stdout);
#define CNAT_ICMP_DEST_UNREACHABLE 100
#define INCREMENT_NODE_COUNTER(c) \
em->counters[node_counter_base_index + c] += 1;
#define V4_TCP_UPDATE_SESSION_FLAG(db, tcp) \
if ((tcp->flags & TCP_FLAG_ACK) && (tcp->flags & TCP_FLAG_SYN)) { \
db->flags |= CNAT_DB_FLAG_TCP_ACTIVE; \
} \
if ((tcp->flags & TCP_FLAG_RST) || (tcp->flags & TCP_FLAG_FIN)) { \
db->flags &= ~CNAT_DB_FLAG_TCP_ACTIVE; \
db->flags |= CNAT_DB_FLAG_TCP_CLOSING; \
}
#define V4_TCP_UPDATE_SESSION_DB_FLAG(sdb, tcp) \
if ((tcp->flags & TCP_FLAG_ACK) && (tcp->flags & TCP_FLAG_SYN)) { \
sdb->flags |= CNAT_DB_FLAG_TCP_ACTIVE; \
} \
if ((tcp->flags & TCP_FLAG_RST) || (tcp->flags & TCP_FLAG_FIN)) { \
sdb->flags &= ~CNAT_DB_FLAG_TCP_ACTIVE; \
sdb->flags |= CNAT_DB_FLAG_TCP_CLOSING; \
}
/*
* Code to recalculate checksum after ACK/SEQ number changes
* This macro assumes, we have pointer to tcp structure
* referenced by the name "tcp"
*/
#define CNAT_UPDATE_TCP_SEQ_ACK_CHECKSUM(old_val32, new_val32) \
{ \
u16 old_val_lower, old_val_upper, old_tcp_cr; \
u16 new_val_lower, new_val_upper, new_tcp_cr; \
u32 sum32; \
\
old_val_lower = ~((u16) old_val32); \
old_val_upper = ~((u16) (old_val32 >> 16)); \
old_tcp_cr = ~net2host16(&tcp->tcp_checksum); \
new_val_lower = (u16) new_val32; \
new_val_upper = (u16) (new_val32 >> 16); \
\
sum32 = old_val_lower + old_val_upper + old_tcp_cr + \
new_val_lower + new_val_upper; \
\
sum32 = (sum32 & 0xffff) + ((sum32 >> 16) & 0xffff); \
sum32 = (sum32 & 0xffff) + ((sum32 >> 16) & 0xffff); \
new_tcp_cr = ~((u16)sum32); \
\
tcp->tcp_checksum = host2net16(new_tcp_cr); \
}
/*
* newchecksum = ~(~oldchecksum + ~old + new)
* old/new for l3 checksum: ip address
*/
#define CNAT_UPDATE_L3_CHECKSUM_DECLARE \
u16 old_l3_1r, old_l3_2r; \
u16 old_l3_cr, new_l3_c; \
u32 new32;
#define CNAT_UPDATE_L3_CHECKSUM(old_l3_1, old_l3_2, old_l3_c, \
new_l3_1, new_l3_2) \
old_l3_1r = ~(old_l3_1); \
old_l3_2r = ~(old_l3_2); \
old_l3_cr = ~(old_l3_c); \
new32 = old_l3_cr + old_l3_1r + old_l3_2r + new_l3_1 + new_l3_2; \
new32 = (new32 & 0xffff) + ((new32 >> 16) & 0xffff); \
new32 = (new32 & 0xffff) + ((new32 >> 16) & 0xffff); \
new_l3_c = ~((u16)new32);
/*
* newchecksum = ~(~oldchecksum + ~old + new)
* old/new for l3 checksum: ip address
* old/new for l4 checksum: ip address and port
*/
#define CNAT_UPDATE_L3_L4_CHECKSUM_DECLARE \
u16 old_l3_1r, old_l3_2r, old_l4r; \
u16 old_l3_cr, old_l4_cr; \
u16 new_l3_c, new_l4_c; \
u32 sum32, new32;
#define CNAT_UPDATE_L3_L4_CHECKSUM(old_l3_1, old_l3_2, old_l4, \
old_l3_c, old_l4_c, \
new_l3_1, new_l3_2, new_l4) \
old_l3_1r = ~(old_l3_1); \
old_l3_2r = ~(old_l3_2); \
old_l3_cr = ~(old_l3_c); \
sum32 = old_l3_1r + old_l3_2r + new_l3_1 + new_l3_2; \
new32 = old_l3_cr + sum32; \
new32 = (new32 & 0xffff) + ((new32 >> 16) & 0xffff); \
new32 = (new32 & 0xffff) + ((new32 >> 16) & 0xffff); \
new_l3_c = ~((u16)new32); \
old_l4r = ~(old_l4); \
old_l4_cr = ~(old_l4_c); \
sum32 += old_l4r + new_l4; \
new32 = old_l4_cr + sum32; \
new32 = (new32 & 0xffff) + ((new32 >> 16) & 0xffff); \
new32 = (new32 & 0xffff) + ((new32 >> 16) & 0xffff); \
new_l4_c = ~((u16)new32);
/*
* For ICMP checksums, we don't use the top IP header for checksum calculation
*/
#define CNAT_UPDATE_L3_ICMP_CHECKSUM(old_l3_1, old_l3_2, old_l4, \
old_l3_c, old_l4_c, \
new_l3_1, new_l3_2, new_l4) \
old_l3_1r = ~(old_l3_1); \
old_l3_2r = ~(old_l3_2); \
old_l3_cr = ~(old_l3_c); \
sum32 = old_l3_1r + old_l3_2r + new_l3_1 + new_l3_2; \
new32 = old_l3_cr + sum32; \
new32 = (new32 & 0xffff) + ((new32 >> 16) & 0xffff); \
new32 = (new32 & 0xffff) + ((new32 >> 16) & 0xffff); \
new_l3_c = ~((u16)new32); \
old_l4r = ~(old_l4); \
old_l4_cr = ~(old_l4_c); \
sum32 = old_l4r + new_l4; \
new32 = old_l4_cr + sum32; \
new32 = (new32 & 0xffff) + ((new32 >> 16) & 0xffff); \
new32 = (new32 & 0xffff) + ((new32 >> 16) & 0xffff); \
new_l4_c = ~((u16)new32);
/*
* icmp error type message:
* newchecksum = ~(~oldchecksum + ~old + new)
* old/new for outlayer ip checksum: ip address
* old/new for outlayer icmp checksum:
* out-layer: ip address
* inner-layer: ip addr, port, l3 checksum, l4 checksum
*/
#define CNAT_UPDATE_ICMP_ERR_CHECKSUM_DECLARE \
u16 old_ip_1r, old_ip_2r, old_ip_port_r, old_ip_cr, old_icmp_cr; \
u16 new_icmp_c; \
u32 sum32;
#define CNAT_UPDATE_ICMP_ERR_CHECKSUM(old_ip_1, old_ip_2, old_ip_port, old_ip_c, old_icmp_c, \
new_ip_1, new_ip_2, new_ip_port, new_ip_c) \
old_ip_1r = ~(old_ip_1); \
old_ip_2r = ~(old_ip_2); \
old_ip_port_r = ~(old_ip_port); \
old_ip_cr = ~(old_ip_c); \
old_icmp_cr = ~(old_icmp_c); \
sum32 = old_ip_1r + old_ip_2r + new_ip_1 + new_ip_2 + \
old_ip_port_r + new_ip_port + old_ip_cr + new_ip_c; \
new32 = old_icmp_cr + sum32; \
new32 = (new32 & 0xffff) + ((new32 >> 16) & 0xffff); \
new32 = (new32 & 0xffff) + ((new32 >> 16) & 0xffff); \
new_icmp_c = ~((u16)new32); \
/*
* Add the two 16 bit parts of the 32 bit field
* Repeat it one more time to take care of any overflow
* Complement the u16 value and store it in network format
*/
#define FILL_CHECKSUM(checksum_field, sum32) { \
sum32 = (sum32 & 0xffff) + ((sum32>>16) & 0xffff); \
sum32 = (sum32 & 0xffff) + ((sum32>>16) & 0xffff); \
checksum_field = clib_host_to_net_u16(~((u16) sum32)); \
}
static inline void
cnat_v4_recalculate_tcp_checksum (ipv4_header *ip,
tcp_hdr_type *tcp,
u32 *ip_addr_ptr,
u16 *tcp_port_addr_ptr,
u32 new_ip,
u16 new_port)
{
u32 old_ip_addr, old_ip32_r, new_ip32, sum32;
u16 old_port_r, old_ip_checksum_r, old_tcp_checksum_r;
u16 *p16;
p16 = (u16*) ip_addr_ptr;
old_ip_addr = *ip_addr_ptr;
old_ip32_r = (((u16) ~clib_net_to_host_u16(*p16)) +
((u16) ~clib_net_to_host_u16(*(p16+1))));
old_port_r = ~clib_net_to_host_u16(*tcp_port_addr_ptr);
*ip_addr_ptr = clib_host_to_net_u32(new_ip);
new_ip32 = (new_ip & 0xffff) + ((new_ip >> 16) & 0xffff);
old_ip_checksum_r = ~clib_net_to_host_u16(ip->checksum);
/*
* Recalculate the new IP checksum
*/
sum32 = old_ip32_r + new_ip32 + old_ip_checksum_r;
FILL_CHECKSUM(ip->checksum, sum32);
u16 frag_offset =
clib_net_to_host_u16((ip->frag_flags_offset));
if(PREDICT_FALSE(frag_offset & IP_FRAG_OFFSET_MASK)) {
return; /* No need to update TCP fields */
}
*tcp_port_addr_ptr = clib_host_to_net_u16(new_port);
old_tcp_checksum_r = ~clib_net_to_host_u16(tcp->tcp_checksum);
/*
* Recalculate the new TCP checksum
*/
sum32 = old_ip32_r + new_ip32 +
old_port_r + new_port + old_tcp_checksum_r;
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),
clib_net_to_host_u32(old_ip_addr),
clib_net_to_host_u32(*ip_addr_ptr),
~old_port_r,
clib_net_to_host_u16(*tcp_port_addr_ptr),
~old_ip_checksum_r,
clib_net_to_host_u16(ip->checksum),
~old_tcp_checksum_r,
clib_net_to_host_u16(tcp->tcp_checksum));
}
}
extern 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);
void hex_dump(u8 * p, int len);
u32 get_my_svi_intf_ip_addr();
/*
* in cnat_v4_icmp_gen.c,
* return 1 if icmp msg allow to generate
* for this user
*/
u32 icmp_msg_gen_allowed ();
cnat_icmp_msg_t v6_icmp_msg_gen_allowed();
int v4_crc_zero_udp_allowed();
void ipv4_decr_ttl_n_calc_csum(ipv4_header *ipv4);
int icmpv4_generate_with_throttling (spp_ctx_t *ctx, ipv4_header *ipv4,
u16 rx_uidb_index);
int icmpv6_generate_with_throttling (spp_ctx_t *ctx, ipv6_header_t *ipv4,
u16 rx_uidb_index);
void icmp_error_generate_v6(spp_ctx_t *ctx, u8 icmp_type,
u8 icmp_code, u16 uidb_index);
void calculate_window_scale(tcp_hdr_type *tcp_header, u8 *scale);
void cnat_log_nat44_tcp_seq_mismatch(
cnat_main_db_entry_t *db,
cnat_vrfmap_t *vrfmap);
void print_icmp_pkt (ipv4_header *ip);
void print_udp_pkt (ipv4_header *ip);
void print_tcp_pkt (ipv4_header *ip);
void print_ipv6_pkt (ipv6_header_t *ip);
#endif