From ceb5cf3200245cc9b5686dc5a4540de7417e85b8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Anton=20Luka=20=C5=A0ijanec?= <anton@sijanec.eu>
Date: Thu, 3 Aug 2023 23:50:57 +0200
Subject: raw6

---
 skripti/raw6.c | 153 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 153 insertions(+)
 create mode 100644 skripti/raw6.c

diff --git a/skripti/raw6.c b/skripti/raw6.c
new file mode 100644
index 0000000..c0fb130
--- /dev/null
+++ b/skripti/raw6.c
@@ -0,0 +1,153 @@
+#define _GNU_SOURCE
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netinet/ip6.h>
+#include <netinet/udp.h>
+#include <stdio.h>
+#include <arpa/inet.h>
+#include <string.h>
+#include <signal.h>
+#include <linux/if_packet.h>
+#include <net/ethernet.h>
+#include <net/if.h>
+#include <stdlib.h>
+#include <arpa/nameser.h>
+#include <assert.h>
+#include "/root/projects/dnsfind/domain2name.c"
+int hex2int (char hex) {
+	if (hex >= '0' && hex <= '9')
+		return hex-'0';
+	if (hex >= 'a' && hex <= 'f')
+		return 10+hex-'a';
+	if (hex >= 'A' && hex <= 'A')
+		return 10+hex-'A';
+	return -1;
+}
+int mac_pton (const char * src, unsigned char * dst) {
+	for (int i = 0; i < 6; i++) {
+		if (hex2int(src[0]) == -1 || hex2int(src[1]) == -1)
+			return 0;
+		dst[i] = hex2int(src[0]) << 4 | hex2int(src[1]);
+		src += 3;
+	}
+	return 1;
+}
+unsigned long checksum (void * data, int len) { // i cant into checksums im retarded
+	unsigned sum = 0;
+	for (int i = 0; i+1 < len; i += 2)
+		sum += *((unsigned char *) data + i)*256+*((unsigned char *) data + i + 1);
+	if (len % 2)
+		sum += ((unsigned char *) data)[len-1];
+	return sum;
+}
+uint16_t checksum_final (unsigned long sum) {
+	sum += sum >> 16;
+	sum &= 0xffff;
+	sum ^= 0xffff;
+	if (sum == 0)
+		sum = 0xffff;
+	return htons(sum);
+}
+int main (int argc, char ** argv) {
+	if (argc != 5) {
+		fprintf(stderr, "%s <dst ipv6> <src ipv6> <if index> <router mac> <querydomain>\n", argv[0]);
+		return 4;
+	}
+	int sock = socket(AF_PACKET, SOCK_DGRAM, htons(ETHERTYPE_IPV6));
+	if (sock == -1) {
+		perror("socket(AF_PACKET, SOCK_DGRAM, htons(ETHERTYPE_IPV6)");
+		return 1;
+	}
+	HEADER dns = {
+		.id = htons(0x1337),
+		.qr = 0, // question
+		.opcode = ns_o_query,
+		.rd = 1, // recursion
+		.qdcount = htons(1)
+	};
+	unsigned char question[5] = "";
+	*((uint16_t *) (question+1)) = htons(ns_t_any);
+	*((uint16_t *) (question+3)) = htons(ns_c_in);
+	struct udphdr udp = {
+		.source = htons(6969),
+		.dest = htons(53),
+		.len = htons(8+sizeof dns+sizeof question)
+	};
+	struct ip6_hdr ip6 = {
+		.ip6_ctlun.ip6_un1.ip6_un1_plen = udp.len,
+		.ip6_ctlun.ip6_un1.ip6_un1_hlim = 255,
+		.ip6_ctlun.ip6_un1.ip6_un1_nxt = IPPROTO_UDP
+	};
+	ip6.ip6_ctlun.ip6_un2_vfc |= 0x60;
+	switch (inet_pton(AF_INET6, argv[1], ip6.ip6_dst.s6_addr)) {
+		case -1:
+			perror("inet_pton(AF_INET6, argv[1])");
+			return 2;
+			break;
+		case 0:
+			fprintf(stderr, "naslov %s ni veljaven\n", argv[1]);
+			return 12;
+			break;
+	}
+	switch (inet_pton(AF_INET6, argv[2], ip6.ip6_src.s6_addr)) {
+		case -1:
+			perror("inet_pton(AF_INET6, argv[2])");
+			return 9;
+			break;
+		case 0:
+			fprintf(stderr, "naslov %s ni veljaven\n", argv[1]);
+			return 11;
+			break;
+	}
+	struct iovec msg[] = {
+		{
+			.iov_base = &ip6,
+			.iov_len = sizeof ip6
+		},
+		{
+			.iov_base = &udp,
+			.iov_len = sizeof udp
+		},
+		{
+			.iov_base = &dns,
+			.iov_len = sizeof dns
+		},
+		{
+			.iov_base = &question,
+			.iov_len = sizeof question
+		}
+	};
+	unsigned long sum = ip6.ip6_ctlun.ip6_un1.ip6_un1_nxt + checksum(&ip6.ip6_ctlun.ip6_un1.ip6_un1_plen, sizeof(uint16_t)) + checksum(&ip6.ip6_src, sizeof ip6.ip6_src) + checksum(&ip6.ip6_dst, sizeof ip6.ip6_dst);
+	for (size_t i = 1; i < sizeof msg/sizeof msg[0]; i++)
+		sum += checksum(msg[i].iov_base, msg[i].iov_len);
+	udp.check = checksum_final(sum);
+	udp.check = 0;
+	int ifindex = atoi(argv[3]);
+	struct sockaddr_ll dst = {
+		.sll_family = AF_PACKET,
+		.sll_ifindex = ifindex,
+		.sll_halen = 6,
+		.sll_protocol = htons(ETHERTYPE_IPV6)
+	};
+	if (!mac_pton(argv[4], dst.sll_addr)) {
+		fprintf(stderr, "naslov %s ni veljaven\n", argv[4]);
+		return 13;
+	}
+	struct mmsghdr mmsghdr = {
+		.msg_hdr = {
+			.msg_name = &dst,
+			.msg_namelen = sizeof dst,
+			.msg_iov = msg,
+			.msg_iovlen = sizeof msg / sizeof msg[0]
+		}
+	};
+	/* if (sendmmsg(sock, &mmsghdr, 1, 0) == -1) {
+		perror("sendmmsg(sock, &mmsghdr, 1, 0)");
+		return 3;
+	} */
+	if (sendmsg(sock, &mmsghdr.msg_hdr, 0) == -1) {
+		perror("sendmsg");
+		return 5;
+	}
+	return 0;
+}
-- 
cgit v1.2.3