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/*
* 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.
*/
/*
* ip/ip4_input.c: IP v4 input node
*
* Copyright (c) 2008 Eliot Dresselhaus
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#ifndef included_ip_input_h
#define included_ip_input_h
#include <vnet/ip/ip.h>
#include <vnet/ethernet/ethernet.h>
extern char *ip4_error_strings[];
typedef enum
{
IP4_INPUT_NEXT_DROP,
IP4_INPUT_NEXT_PUNT,
IP4_INPUT_NEXT_LOOKUP,
IP4_INPUT_NEXT_LOOKUP_MULTICAST,
IP4_INPUT_NEXT_ICMP_ERROR,
IP4_INPUT_NEXT_REASSEMBLY,
IP4_INPUT_N_NEXT,
} ip4_input_next_t;
static_always_inline void
check_ver_opt_csum (ip4_header_t * ip, u8 * error, int verify_checksum)
{
if (PREDICT_FALSE (ip->ip_version_and_header_length != 0x45))
{
if ((ip->ip_version_and_header_length & 0xf) != 5)
{
*error = IP4_ERROR_OPTIONS;
if (verify_checksum && ip_csum (ip, ip4_header_bytes (ip)) != 0)
*error = IP4_ERROR_BAD_CHECKSUM;
}
else
*error = IP4_ERROR_VERSION;
}
else
if (PREDICT_FALSE (verify_checksum &&
ip_csum (ip, sizeof (ip4_header_t)) != 0))
*error = IP4_ERROR_BAD_CHECKSUM;
}
always_inline void
ip4_input_check_x4 (vlib_main_t * vm,
vlib_node_runtime_t * error_node,
vlib_buffer_t ** p, ip4_header_t ** ip,
u16 * next, int verify_checksum)
{
u8 error0, error1, error2, error3;
u32 ip_len0, cur_len0;
u32 ip_len1, cur_len1;
u32 ip_len2, cur_len2;
u32 ip_len3, cur_len3;
i32 len_diff0, len_diff1, len_diff2, len_diff3;
error0 = error1 = error2 = error3 = IP4_ERROR_NONE;
check_ver_opt_csum (ip[0], &error0, verify_checksum);
check_ver_opt_csum (ip[1], &error1, verify_checksum);
check_ver_opt_csum (ip[2], &error2, verify_checksum);
check_ver_opt_csum (ip[3], &error3, verify_checksum);
if (PREDICT_FALSE (ip[0]->ttl < 1))
error0 = IP4_ERROR_TIME_EXPIRED;
if (PREDICT_FALSE (ip[1]->ttl < 1))
error1 = IP4_ERROR_TIME_EXPIRED;
if (PREDICT_FALSE (ip[2]->ttl < 1))
error2 = IP4_ERROR_TIME_EXPIRED;
if (PREDICT_FALSE (ip[3]->ttl < 1))
error3 = IP4_ERROR_TIME_EXPIRED;
/* Drop fragmentation offset 1 packets. */
error0 = ip4_get_fragment_offset (ip[0]) == 1 ?
IP4_ERROR_FRAGMENT_OFFSET_ONE : error0;
error1 = ip4_get_fragment_offset (ip[1]) == 1 ?
IP4_ERROR_FRAGMENT_OFFSET_ONE : error1;
error2 = ip4_get_fragment_offset (ip[2]) == 1 ?
IP4_ERROR_FRAGMENT_OFFSET_ONE : error2;
error3 = ip4_get_fragment_offset (ip[3]) == 1 ?
IP4_ERROR_FRAGMENT_OFFSET_ONE : error3;
/* Verify lengths. */
ip_len0 = clib_net_to_host_u16 (ip[0]->length);
ip_len1 = clib_net_to_host_u16 (ip[1]->length);
ip_len2 = clib_net_to_host_u16 (ip[2]->length);
ip_len3 = clib_net_to_host_u16 (ip[3]->length);
/* IP length must be at least minimal IP header. */
error0 = ip_len0 < sizeof (ip[0][0]) ? IP4_ERROR_TOO_SHORT : error0;
error1 = ip_len1 < sizeof (ip[1][0]) ? IP4_ERROR_TOO_SHORT : error1;
error2 = ip_len2 < sizeof (ip[2][0]) ? IP4_ERROR_TOO_SHORT : error2;
error3 = ip_len3 < sizeof (ip[3][0]) ? IP4_ERROR_TOO_SHORT : error3;
cur_len0 = vlib_buffer_length_in_chain (vm, p[0]);
cur_len1 = vlib_buffer_length_in_chain (vm, p[1]);
cur_len2 = vlib_buffer_length_in_chain (vm, p[2]);
cur_len3 = vlib_buffer_length_in_chain (vm, p[3]);
len_diff0 = cur_len0 - ip_len0;
len_diff1 = cur_len1 - ip_len1;
len_diff2 = cur_len2 - ip_len2;
len_diff3 = cur_len3 - ip_len3;
error0 = len_diff0 < 0 ? IP4_ERROR_BAD_LENGTH : error0;
error1 = len_diff1 < 0 ? IP4_ERROR_BAD_LENGTH : error1;
error2 = len_diff2 < 0 ? IP4_ERROR_BAD_LENGTH : error2;
error3 = len_diff3 < 0 ? IP4_ERROR_BAD_LENGTH : error3;
if (PREDICT_FALSE (error0 != IP4_ERROR_NONE))
{
if (error0 == IP4_ERROR_TIME_EXPIRED)
{
icmp4_error_set_vnet_buffer (p[0], ICMP4_time_exceeded,
ICMP4_time_exceeded_ttl_exceeded_in_transit,
0);
next[0] = IP4_INPUT_NEXT_ICMP_ERROR;
}
else
next[0] = error0 != IP4_ERROR_OPTIONS ?
IP4_INPUT_NEXT_DROP : IP4_INPUT_NEXT_PUNT;
p[0]->error = error_node->errors[error0];
}
if (PREDICT_FALSE (error1 != IP4_ERROR_NONE))
{
if (error1 == IP4_ERROR_TIME_EXPIRED)
{
icmp4_error_set_vnet_buffer (p[1], ICMP4_time_exceeded,
ICMP4_time_exceeded_ttl_exceeded_in_transit,
0);
next[1] = IP4_INPUT_NEXT_ICMP_ERROR;
}
else
next[1] = error1 != IP4_ERROR_OPTIONS ?
IP4_INPUT_NEXT_DROP : IP4_INPUT_NEXT_PUNT;
p[1]->error = error_node->errors[error1];
}
if (PREDICT_FALSE (error2 != IP4_ERROR_NONE))
{
if (error2 == IP4_ERROR_TIME_EXPIRED)
{
icmp4_error_set_vnet_buffer (p[2], ICMP4_time_exceeded,
ICMP4_time_exceeded_ttl_exceeded_in_transit,
0);
next[2] = IP4_INPUT_NEXT_ICMP_ERROR;
}
else
next[2] = error2 != IP4_ERROR_OPTIONS ?
IP4_INPUT_NEXT_DROP : IP4_INPUT_NEXT_PUNT;
p[2]->error = error_node->errors[error2];
}
if (PREDICT_FALSE (error3 != IP4_ERROR_NONE))
{
if (error3 == IP4_ERROR_TIME_EXPIRED)
{
icmp4_error_set_vnet_buffer (p[3], ICMP4_time_exceeded,
ICMP4_time_exceeded_ttl_exceeded_in_transit,
0);
next[3] = IP4_INPUT_NEXT_ICMP_ERROR;
}
else
next[3] = error3 != IP4_ERROR_OPTIONS ?
IP4_INPUT_NEXT_DROP : IP4_INPUT_NEXT_PUNT;
p[3]->error = error_node->errors[error3];
}
}
always_inline void
ip4_input_check_x2 (vlib_main_t * vm,
vlib_node_runtime_t * error_node,
vlib_buffer_t * p0, vlib_buffer_t * p1,
ip4_header_t * ip0, ip4_header_t * ip1,
u32 * next0, u32 * next1, int verify_checksum)
{
u8 error0, error1;
u32 ip_len0, cur_len0;
u32 ip_len1, cur_len1;
i32 len_diff0, len_diff1;
error0 = error1 = IP4_ERROR_NONE;
check_ver_opt_csum (ip0, &error0, verify_checksum);
check_ver_opt_csum (ip1, &error1, verify_checksum);
if (PREDICT_FALSE (ip0->ttl < 1))
error0 = IP4_ERROR_TIME_EXPIRED;
if (PREDICT_FALSE (ip1->ttl < 1))
error1 = IP4_ERROR_TIME_EXPIRED;
/* Drop fragmentation offset 1 packets. */
error0 = ip4_get_fragment_offset (ip0) == 1 ?
IP4_ERROR_FRAGMENT_OFFSET_ONE : error0;
error1 = ip4_get_fragment_offset (ip1) == 1 ?
IP4_ERROR_FRAGMENT_OFFSET_ONE : error1;
/* Verify lengths. */
ip_len0 = clib_net_to_host_u16 (ip0->length);
ip_len1 = clib_net_to_host_u16 (ip1->length);
/* IP length must be at least minimal IP header. */
error0 = ip_len0 < sizeof (ip0[0]) ? IP4_ERROR_TOO_SHORT : error0;
error1 = ip_len1 < sizeof (ip1[0]) ? IP4_ERROR_TOO_SHORT : error1;
cur_len0 = vlib_buffer_length_in_chain (vm, p0);
cur_len1 = vlib_buffer_length_in_chain (vm, p1);
len_diff0 = cur_len0 - ip_len0;
len_diff1 = cur_len1 - ip_len1;
error0 = len_diff0 < 0 ? IP4_ERROR_BAD_LENGTH : error0;
error1 = len_diff1 < 0 ? IP4_ERROR_BAD_LENGTH : error1;
if (PREDICT_FALSE (error0 != IP4_ERROR_NONE))
{
if (error0 == IP4_ERROR_TIME_EXPIRED)
{
icmp4_error_set_vnet_buffer (p0, ICMP4_time_exceeded,
ICMP4_time_exceeded_ttl_exceeded_in_transit,
0);
*next0 = IP4_INPUT_NEXT_ICMP_ERROR;
}
else
*next0 = error0 != IP4_ERROR_OPTIONS ?
IP4_INPUT_NEXT_DROP : IP4_INPUT_NEXT_PUNT;
p0->error = error_node->errors[error0];
}
if (PREDICT_FALSE (error1 != IP4_ERROR_NONE))
{
if (error1 == IP4_ERROR_TIME_EXPIRED)
{
icmp4_error_set_vnet_buffer (p1, ICMP4_time_exceeded,
ICMP4_time_exceeded_ttl_exceeded_in_transit,
0);
*next1 = IP4_INPUT_NEXT_ICMP_ERROR;
}
else
*next1 = error1 != IP4_ERROR_OPTIONS ?
IP4_INPUT_NEXT_DROP : IP4_INPUT_NEXT_PUNT;
p1->error = error_node->errors[error1];
}
}
always_inline void
ip4_input_check_x1 (vlib_main_t * vm,
vlib_node_runtime_t * error_node,
vlib_buffer_t * p0,
ip4_header_t * ip0, u32 * next0, int verify_checksum)
{
u32 ip_len0, cur_len0;
i32 len_diff0;
u8 error0;
error0 = IP4_ERROR_NONE;
check_ver_opt_csum (ip0, &error0, verify_checksum);
/* Punt packets with options or wrong version. */
if (PREDICT_FALSE (ip0->ip_version_and_header_length != 0x45))
error0 = (ip0->ip_version_and_header_length & 0xf) != 5 ?
IP4_ERROR_OPTIONS : IP4_ERROR_VERSION;
/* Drop fragmentation offset 1 packets. */
error0 = ip4_get_fragment_offset (ip0) == 1 ?
IP4_ERROR_FRAGMENT_OFFSET_ONE : error0;
/* Verify lengths. */
ip_len0 = clib_net_to_host_u16 (ip0->length);
/* IP length must be at least minimal IP header. */
error0 = ip_len0 < sizeof (ip0[0]) ? IP4_ERROR_TOO_SHORT : error0;
cur_len0 = vlib_buffer_length_in_chain (vm, p0);
len_diff0 = cur_len0 - ip_len0;
error0 = len_diff0 < 0 ? IP4_ERROR_BAD_LENGTH : error0;
if (PREDICT_FALSE (error0 != IP4_ERROR_NONE))
{
if (error0 == IP4_ERROR_TIME_EXPIRED)
{
icmp4_error_set_vnet_buffer (p0, ICMP4_time_exceeded,
ICMP4_time_exceeded_ttl_exceeded_in_transit,
0);
*next0 = IP4_INPUT_NEXT_ICMP_ERROR;
}
else
*next0 = error0 != IP4_ERROR_OPTIONS ?
IP4_INPUT_NEXT_DROP : IP4_INPUT_NEXT_PUNT;
p0->error = error_node->errors[error0];
}
}
/*
* fd.io coding-style-patch-verification: ON
*
* Local Variables:
* eval: (c-set-style "gnu")
* End:
*/
#endif
|
