87 lines
2.8 KiB
C
87 lines
2.8 KiB
C
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/**
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* @file ipv6_proto.h
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* @author Ambroz Bizjak <ambrop7@gmail.com>
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*
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* @section LICENSE
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the author nor the
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* names of its contributors may be used to endorse or promote products
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* derived from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
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* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
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* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
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* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#ifndef BADVPN_IPV6_PROTO_H
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#define BADVPN_IPV6_PROTO_H
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#include <stdint.h>
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#include <string.h>
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#include <misc/debug.h>
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#include <misc/byteorder.h>
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#include <misc/packed.h>
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#define IPV6_NEXT_IGMP 2
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#define IPV6_NEXT_UDP 17
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B_START_PACKED
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struct ipv6_header {
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uint8_t version4_tc4;
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uint8_t tc4_fl4;
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uint16_t fl;
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uint16_t payload_length;
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uint8_t next_header;
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uint8_t hop_limit;
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uint8_t source_address[16];
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uint8_t destination_address[16];
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} B_PACKED;
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B_END_PACKED
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static int ipv6_check (uint8_t *data, int data_len, struct ipv6_header *out_header, uint8_t **out_payload, int *out_payload_len)
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{
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ASSERT(data_len >= 0)
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ASSERT(out_header)
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ASSERT(out_payload)
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ASSERT(out_payload_len)
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// check base header
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if (data_len < sizeof(struct ipv6_header)) {
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return 0;
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}
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memcpy(out_header, data, sizeof(*out_header));
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// check version
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if ((ntoh8(out_header->version4_tc4) >> 4) != 6) {
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return 0;
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}
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// check payload length
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uint16_t payload_length = ntoh16(out_header->payload_length);
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if (payload_length > data_len - sizeof(struct ipv6_header)) {
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return 0;
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}
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*out_payload = data + sizeof(struct ipv6_header);
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*out_payload_len = payload_length;
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return 1;
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}
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#endif
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