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/*
* Copyright (c) 2018 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.
*/
/**
* @file
* @brief NAT66 inside to outside network translation
*/
#include <nat/nat66/nat66.h>
#include <vnet/ip/ip6_to_ip4.h>
#include <vnet/fib/fib_table.h>
typedef struct
{
u32 sw_if_index;
u32 next_index;
} nat66_in2out_trace_t;
static u8 *
format_nat66_in2out_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 *);
nat66_in2out_trace_t *t = va_arg (*args, nat66_in2out_trace_t *);
s =
format (s, "NAT66-in2out: sw_if_index %d, next index %d", t->sw_if_index,
t->next_index);
return s;
}
#define foreach_nat66_in2out_error \
_(NO_TRANSLATION, "no translation") \
_(UNKNOWN, "unknown")
typedef enum
{
#define _(sym,str) NAT66_IN2OUT_ERROR_##sym,
foreach_nat66_in2out_error
#undef _
NAT66_IN2OUT_N_ERROR,
} nat66_in2out_error_t;
static char *nat66_in2out_error_strings[] = {
#define _(sym,string) string,
foreach_nat66_in2out_error
#undef _
};
typedef enum
{
NAT66_IN2OUT_NEXT_IP6_LOOKUP,
NAT66_IN2OUT_NEXT_DROP,
NAT66_IN2OUT_N_NEXT,
} nat66_in2out_next_t;
static inline u8
nat66_not_translate (u32 rx_fib_index, ip6_address_t ip6_addr)
{
nat66_main_t *nm = &nat66_main;
u32 sw_if_index;
nat66_interface_t *i;
fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
fib_prefix_t pfx = {
.fp_proto = FIB_PROTOCOL_IP6,
.fp_len = 128,
.fp_addr = {
.ip6 = ip6_addr,
},
};
fei = fib_table_lookup (rx_fib_index, &pfx);
if (FIB_NODE_INDEX_INVALID == fei)
return 1;
sw_if_index = fib_entry_get_resolving_interface (fei);
if (sw_if_index == ~0)
{
fei = fib_table_lookup (nm->outside_fib_index, &pfx);
if (FIB_NODE_INDEX_INVALID == fei)
return 1;
sw_if_index = fib_entry_get_resolving_interface (fei);
}
/* *INDENT-OFF* */
pool_foreach (i, nm->interfaces,
({
/* NAT packet aimed at outside interface */
if (nat66_interface_is_outside (i) && sw_if_index == i->sw_if_index)
return 0;
}));
/* *INDENT-ON* */
return 1;
}
VLIB_NODE_FN (nat66_in2out_node) (vlib_main_t * vm,
vlib_node_runtime_t * node,
vlib_frame_t * frame)
{
u32 n_left_from, *from, *to_next;
nat66_in2out_next_t next_index;
u32 thread_index = vm->thread_index;
nat66_main_t *nm = &nat66_main;
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);
while (n_left_from > 0 && n_left_to_next > 0)
{
u32 bi0;
vlib_buffer_t *b0;
u32 next0 = NAT66_IN2OUT_NEXT_IP6_LOOKUP;
ip6_header_t *ip60;
u16 l4_offset0, frag_offset0;
u8 l4_protocol0;
nat66_static_mapping_t *sm0;
u32 sw_if_index0, fib_index0;
udp_header_t *udp0;
tcp_header_t *tcp0;
icmp46_header_t *icmp0;
u16 *checksum0 = 0;
ip_csum_t csum0;
/* 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);
ip60 = vlib_buffer_get_current (b0);
if (PREDICT_FALSE
(ip6_parse
(vm, b0, ip60, b0->current_length, &l4_protocol0, &l4_offset0,
&frag_offset0)))
{
next0 = NAT66_IN2OUT_NEXT_DROP;
b0->error = node->errors[NAT66_IN2OUT_ERROR_UNKNOWN];
goto trace0;
}
sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
fib_index0 =
fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP6,
sw_if_index0);
if (nat66_not_translate (fib_index0, ip60->dst_address))
goto trace0;
sm0 = nat66_static_mapping_get (&ip60->src_address, fib_index0, 1);
if (PREDICT_FALSE (!sm0))
{
goto trace0;
}
if (l4_protocol0 == IP_PROTOCOL_UDP)
{
udp0 = (udp_header_t *) u8_ptr_add (ip60, l4_offset0);
checksum0 = &udp0->checksum;
}
else if (l4_protocol0 == IP_PROTOCOL_TCP)
{
tcp0 = (tcp_header_t *) u8_ptr_add (ip60, l4_offset0);
checksum0 = &tcp0->checksum;
}
else if (l4_protocol0 == IP_PROTOCOL_ICMP6)
{
icmp0 = (icmp46_header_t *) u8_ptr_add (ip60, l4_offset0);
checksum0 = &icmp0->checksum;
}
else
goto skip_csum0;
csum0 = ip_csum_sub_even (*checksum0, ip60->src_address.as_u64[0]);
csum0 = ip_csum_sub_even (csum0, ip60->src_address.as_u64[1]);
csum0 = ip_csum_add_even (csum0, sm0->e_addr.as_u64[0]);
csum0 = ip_csum_add_even (csum0, sm0->e_addr.as_u64[1]);
*checksum0 = ip_csum_fold (csum0);
skip_csum0:
ip60->src_address.as_u64[0] = sm0->e_addr.as_u64[0];
ip60->src_address.as_u64[1] = sm0->e_addr.as_u64[1];
vlib_increment_combined_counter (&nm->session_counters,
thread_index, sm0 - nm->sm, 1,
vlib_buffer_length_in_chain (vm,
b0));
trace0:
if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
&& (b0->flags & VLIB_BUFFER_IS_TRACED)))
{
nat66_in2out_trace_t *t =
vlib_add_trace (vm, node, b0, sizeof (*t));
t->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
t->next_index = next0;
}
if (next0 != NAT66_IN2OUT_NEXT_DROP)
{
vlib_increment_simple_counter (&nm->in2out_packets,
thread_index, sw_if_index0, 1);
}
/* 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);
}
return frame->n_vectors;
}
/* *INDENT-OFF* */
VLIB_REGISTER_NODE (nat66_in2out_node) = {
.name = "nat66-in2out",
.vector_size = sizeof (u32),
.format_trace = format_nat66_in2out_trace,
.type = VLIB_NODE_TYPE_INTERNAL,
.n_errors = ARRAY_LEN (nat66_in2out_error_strings),
.error_strings = nat66_in2out_error_strings,
.n_next_nodes = NAT66_IN2OUT_N_NEXT,
/* edit / add dispositions here */
.next_nodes = {
[NAT66_IN2OUT_NEXT_DROP] = "error-drop",
[NAT66_IN2OUT_NEXT_IP6_LOOKUP] = "ip6-lookup",
},
};
/* *INDENT-ON* */
/*
* fd.io coding-style-patch-verification: ON
*
* Local Variables:
* eval: (c-set-style "gnu")
* End:
*/
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