mirror of
https://github.com/oxen-io/lokinet.git
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56 lines
1006 B
C++
56 lines
1006 B
C++
#include <llarp/endian.h>
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#include <algorithm>
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#include <llarp/ip.hpp>
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#include "llarp/buffer.hpp"
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#include "mem.hpp"
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namespace llarp
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{
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namespace net
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{
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bool
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IPv4Packet::Load(llarp_buffer_t pkt)
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{
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#ifndef MIN
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#define MIN(a, b) (a < b ? a : b)
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sz = MIN(pkt.sz, sizeof(buf));
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#undef MIN
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#endif
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memcpy(buf, pkt.base, sz);
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return true;
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}
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llarp_buffer_t
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IPv4Packet::Buffer()
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{
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return llarp::InitBuffer(buf, sz);
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}
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void
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IPv4Packet::UpdateChecksum()
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{
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auto hdr = Header();
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hdr->check = 0;
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size_t count = hdr->ihl;
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uint32_t sum = 0;
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byte_t *addr = buf;
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while(count > 1)
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{
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sum += ntohs(*(uint16_t *)addr);
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count -= sizeof(uint16_t);
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addr += sizeof(uint16_t);
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}
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if(count > 0)
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sum += *(byte_t *)addr;
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while(sum >> 16)
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sum = (sum & 0xffff) + (sum >> 16);
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hdr->check = htons(~sum);
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}
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} // namespace net
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} // namespace llarp
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