#define _GNU_SOURCE // sendmmsg

#include <netinet/in.h>

#include <stdio.h>

#include <stdlib.h>

#include <sys/socket.h>

#include <errno.h>

#include "common.h"

struct state {

struct net_addr *target_addr;

int packets_in_buf;

const char *payload;

int payload_sz;

int src_port;

};

void thread_loop(void *userdata) {

struct state *state = userdata;

struct mmsghdr *messages = calloc(state->packets_in_buf, sizeof(struct mmsghdr));

struct iovec *iovecs = calloc(state->packets_in_buf, sizeof(struct iovec));

int fd = net_connect_udp(state->target_addr, state->src_port);

int i;

for (i = 0; i < state->packets_in_buf; i++) {

struct iovec *iovec = &iovecs[i];

struct mmsghdr *msg = &messages[i];

msg->msg_hdr.msg_iov = iovec;

msg->msg_hdr.msg_iovlen = 1;

iovec->iov_base = (void*)state->payload;

iovec->iov_len = state->payload_sz;

}

while (1) {

int r = sendmmsg(fd, messages, state->packets_in_buf, 0);

if (r <= 0) {

if (errno == EAGAIN || errno == EWOULDBLOCK || errno == EINTR) {

continue;

}

if (errno == ECONNREFUSED) {

continue;

}

PFATAL("sendmmsg()");

}

int i, bytes = 0;

for (i = 0; i < r; i++) {

struct mmsghdr *msg = &messages[i];

/* char *buf = msg->msg_hdr.msg_iov->iov_base; */

int len = msg->msg_len;

msg->msg_hdr.msg_flags = 0;

msg->msg_len = 0;

bytes += len;

}

}

}

int main(int argc, const char *argv[])

{

int packets_in_buf = 1024;

const char *payload = (const char[32]){0};

int payload_sz = 32;

if (argc == 1) {

FATAL("Usage: %s [target ip:port] [target ...]", argv[0]);

}

struct net_addr *target_addrs = calloc(argc-1, sizeof(struct net_addr));

int thread_num = argc - 1;

int t;

for (t = 0; t < thread_num; t++) {

const char *target_addr_str = argv[t+1];

parse_addr(&target_addrs[t], target_addr_str);

fprintf(stderr, "[*] Sending to %s, send buffer %i packets\n",

addr_to_str(&target_addrs[t]), packets_in_buf);

}

struct state *array_of_states = calloc(thread_num, sizeof(struct state));

for (t = 0; t < thread_num; t++) {

struct state *state = &array_of_states[t];

state->target_addr = &target_addrs[t];

state->packets_in_buf = packets_in_buf;

state->payload = payload;

state->payload_sz = payload_sz;

state->src_port = 11404;

thread_spawn(thread_loop, state);

}

while (1) {

struct timeval timeout =

NSEC_TIMEVAL(MSEC_NSEC(1000UL));

while (1) {

int r = select(0, NULL, NULL, NULL, &timeout);

if (r != 0) {

continue;

}

if (TIMEVAL_NSEC(&timeout) == 0) {

break;

}

}

// pass

}

return 0;

}