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Diffstat (limited to 'src/vnet/ip/ip4_input.h')
| -rw-r--r-- | src/vnet/ip/ip4_input.h | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/src/vnet/ip/ip4_input.h b/src/vnet/ip/ip4_input.h new file mode 100644 index 00000000000..75306a34db3 --- /dev/null +++ b/src/vnet/ip/ip4_input.h @@ -0,0 +1,223 @@ +/* + * 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_N_NEXT, +} ip4_input_next_t; + +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; + + /* 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; + + if (PREDICT_FALSE (ip1->ip_version_and_header_length != 0x45)) + error1 = (ip1->ip_version_and_header_length & 0xf) != 5 ? + IP4_ERROR_OPTIONS : IP4_ERROR_VERSION; + + if (PREDICT_FALSE (ip0->ttl < 1)) + error0 = IP4_ERROR_TIME_EXPIRED; + if (PREDICT_FALSE (ip1->ttl < 1)) + error1 = IP4_ERROR_TIME_EXPIRED; + + /* Verify header checksum. */ + if (verify_checksum) + { + ip_csum_t sum0, sum1; + + ip4_partial_header_checksum_x1 (ip0, sum0); + ip4_partial_header_checksum_x1 (ip1, sum1); + + error0 = 0xffff != ip_csum_fold (sum0) ? + IP4_ERROR_BAD_CHECKSUM : error0; + error1 = 0xffff != ip_csum_fold (sum1) ? + IP4_ERROR_BAD_CHECKSUM : error1; + } + + /* 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; + } + 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; + } + + p0->error = error_node->errors[error0]; + 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; + + /* 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; + + /* Verify header checksum. */ + if (verify_checksum) + { + ip_csum_t sum0; + + ip4_partial_header_checksum_x1 (ip0, sum0); + + error0 = 0xffff != ip_csum_fold (sum0) ? + IP4_ERROR_BAD_CHECKSUM : error0; + } + + /* 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 |