mirror of
https://code.semirocket.science/wrapsix
synced 2024-09-20 07:11:06 +03:00
4bc68edce5
Written new mechanism of wrapper from scratch in C * It listens to all ICMPv6 packets (for now) and translates them to ICMPv4 ones * It can compute the checksum of the packet as well
31 lines
441 B
C
31 lines
441 B
C
unsigned short checksum(const void *_buf, int len)
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{
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const unsigned short *buf = _buf;
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unsigned sum = 0;
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while (len >= 2) {
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sum += *buf ++;
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if (sum & 0x80000000) {
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sum = (sum & 0xffff) + (sum >> 16);
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}
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len -= 2;
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}
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if (len) {
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unsigned char temp[2];
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temp[0] = *(unsigned char *) buf;
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temp[1] = 0;
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sum += *(unsigned short *) temp;
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}
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while (sum >> 16) {
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sum = (sum & 0xffff) + (sum >> 16);
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}
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return ~sum;
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}
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