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/*
* Copyright (C) 2022 Amazon.com Inc. or its affiliates. All rights reserved.
* SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
*/
#include <arpa/inet.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <unistd.h>
#ifdef __wasi__
#include <wasi_socket_ext.h>
#endif
static int
get_ip_addr_type(char *addr, char *buf)
{
if (inet_pton(AF_INET6, addr, buf)) {
return AF_INET6;
}
if (inet_pton(AF_INET, addr, buf)) {
return AF_INET;
}
return -1;
}
static int
is_valid_addr_type(int addr_type)
{
return !(addr_type == -1
|| (addr_type != AF_INET && addr_type != AF_INET6));
}
static void
init_sockaddr_inet(struct sockaddr_in *addr, char *addr_buffer)
{
addr->sin_family = AF_INET;
addr->sin_port = htons(1234);
memcpy(&(addr->sin_addr), addr_buffer, 4);
}
static void
init_sockaddr_inet6(struct sockaddr_in6 *addr, char *addr_buffer)
{
addr->sin6_family = AF_INET6;
addr->sin6_port = htons(1234);
memcpy(&(addr->sin6_addr), addr_buffer, 16);
}
int
main(int argc, char *argv[])
{
struct sockaddr_storage addr = { 0 };
int sd;
char *databuf = "Test message";
int datalen = strlen(databuf) + 1;
char multicast_addr_buffer[16];
int addr_type = -1;
int multicast_interface;
int bool_opt = 1;
if (argc < 2) {
printf("Usage is <Multicast IP>\n");
return EXIT_FAILURE;
}
addr_type = get_ip_addr_type(argv[1], multicast_addr_buffer);
if (!is_valid_addr_type(addr_type)) {
printf("Not a valid ipv4 or ipv6 address\n");
return EXIT_FAILURE;
}
if ((sd = socket(addr_type, SOCK_DGRAM, 0)) == -1) {
return EXIT_FAILURE;
}
if (setsockopt(sd, SOL_SOCKET, SO_REUSEADDR, &bool_opt, sizeof(bool_opt))
== -1) {
perror("Failed setting SO_REUSEADDR");
goto fail;
}
if (addr_type == AF_INET) {
multicast_interface = htonl(INADDR_ANY);
if (setsockopt(sd, IPPROTO_IP, IP_MULTICAST_IF,
(char *)&multicast_interface,
sizeof(multicast_interface))) {
perror("Failed setting local interface");
goto fail;
}
init_sockaddr_inet((struct sockaddr_in *)&addr, multicast_addr_buffer);
}
else {
multicast_interface = 0;
if (setsockopt(sd, IPPROTO_IPV6, IPV6_MULTICAST_IF,
(char *)&multicast_interface,
sizeof(multicast_interface))) {
perror("Failed setting local interface");
goto fail;
}
init_sockaddr_inet6((struct sockaddr_in6 *)&addr,
multicast_addr_buffer);
}
if (sendto(sd, databuf, datalen, 0, (struct sockaddr *)&addr, sizeof(addr))
== -1) {
perror("Failed sending datagram");
goto fail;
}
printf("Datagram sent\n");
close(sd);
return EXIT_SUCCESS;
fail:
close(sd);
return EXIT_FAILURE;
}
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