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#include <camellia/syscalls.h>
#include <stdlib.h>
#include <string.h>
#include "proto.h"
#include "util.h"
enum {
DstMAC = 0,
SrcMAC = 6,
EtherType = 12,
Payload = 14,
};
void ether_parse(const uint8_t *buf, size_t len) {
uint8_t dmac[6], smac[6];
if (len < 60) return;
for (int i = 0; i < 6; i++) dmac[i] = buf[i + DstMAC];
for (int i = 0; i < 6; i++) smac[i] = buf[i + SrcMAC];
printf("from %02x:%02x:%02x:%02x:%02x:%02x\n",
smac[0], smac[1], smac[2], smac[3], smac[4], smac[5]);
printf("to %02x:%02x:%02x:%02x:%02x:%02x\n",
dmac[0], dmac[1], dmac[2], dmac[3], dmac[4], dmac[5]);
uint16_t ethertype = nget16(buf + EtherType);
printf("ethertype %u\n", ethertype);
struct ethernet ether = (struct ethernet){
.src = &smac,
.dst = &dmac,
.type = ethertype,
};
switch (ethertype) {
case ET_IPv4:
ipv4_parse(buf + Payload, len - Payload, ether);
break;
case ET_ARP:
arp_parse(buf + Payload, len - Payload);
break;
default:
printf("(unknown)\n");
break;
}
}
static const size_t fhoff = sizeof(size_t);
uint8_t *ether_start(size_t len, struct ethernet ether) {
if (len < 60 - Payload) len = 60 - Payload;
if (!ether.dst) eprintf("NULL ether.dst!"); // TODO arp? i guess?
if (!ether.src) ether.src = &state.mac;
uint8_t *buf = malloc(fhoff + Payload + len);
memset(buf, 0, fhoff + Payload + len);
*(size_t*)buf = len + Payload;
memcpy(buf + fhoff + DstMAC, ether.dst, 6);
memcpy(buf + fhoff + SrcMAC, ether.src, 6);
nput16(buf + fhoff + EtherType, ether.type);
return buf + fhoff + Payload;
}
void ether_finish(uint8_t *pkt) {
uint8_t *buf = pkt - Payload - fhoff;
size_t len = *(size_t*)buf;
printf("sending:\n");
hexdump(buf + fhoff, len);
_syscall_write(state.raw_h, buf + fhoff, len, 0, 0);
free(buf);
}
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