/* * 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_OPTIONS, 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_OPTIONS; 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_OPTIONS; 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_OPTIONS; 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_OPTIONS; 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_OPTIONS; 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_OPTIONS; 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); if (PREDICT_FALSE (ip0->ttl < 1)) error0 = IP4_ERROR_TIME_EXPIRED; /* 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_OPTIONS; p0->error = error_node->errors[error0]; } } /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */ #endif