user/ethdump: file per protocol, ethernet frame functions

1 files changed, 62 insertions, 0 deletions

diff --git a/src/user/app/ethdump/ether.c b/src/user/app/ethdump/ether.c
new file mode 100644
index 0000000..da21b49
--- /dev/null
+++ b/src/user/app/ethdump/ether.c
@@ -0,0 +1,62 @@
+#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);
+	switch (ethertype) {
+		case ET_IPv4:
+			ipv4_parse(buf + Payload, len - Payload);
+			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);
+}