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#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include "xwrap.h"
#include "l4logger.h"
#include "ump-gai.h"
#include "ump-pkt.h"
#include "ump-app.h"
#include <errno.h>
#include <inttypes.h>
#include <locale.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <time.h>
static volatile sig_atomic_t request_exit = 0;
static void request_exit_setter (int signo) {
request_exit = 1;
}
int main (int argc, char* argv[]) {
setlocale (LC_ALL, "");
tzset ();
if (argc < 4) {
fprintf (stderr, "Usage: %s bind_host bind_port loss_cycle\n", argv[0]);
return 1;
}
long loss_cycle;
if (xatol (argv[3], &loss_cycle) < 0) {
fprintf (stderr, "%s: loss cycle should be an integer\n", argv[0]);
return 1;
}
if (loss_cycle <= 1 || loss_cycle > RAND_MAX) {
fprintf (stderr, "%s: loss cycle must be in range [1, %d)\n",
argv[0],RAND_MAX);
return 1;
}
srand (time (NULL));
struct sigaction sa = {
.sa_handler = request_exit_setter,
.sa_flags = 0
};
sigemptyset (&sa.sa_mask);
sigaction (SIGINT, &sa, NULL);
sigaction (SIGTERM, &sa, NULL);
sa.sa_handler = SIG_IGN;
sigaction (SIGHUP, &sa, NULL);
sigaction (SIGPIPE, &sa, NULL);
LbsLogger agent_log_struct;
LbsLogger* agent_log = &agent_log_struct;
lbs_logger_init (agent_log, LBS_LOGGER_FILE_STDOUT, LBS_LOGGER_COLOR_AUTO,
argv[0], "UMP_AGENT_FILE", "UMP_AGENT_COLOR");
int gai_errno;
int udp_fd = ump_gai (agent_log, argv[1], argv[2], true, NULL, NULL, &gai_errno);
if (udp_fd < 0) {
if (gai_errno) {
fprintf (stderr, "%s: %s\n", argv[0], gai_strerror (gai_errno));
} else {
fprintf (stderr, "%s: %s\n", argv[0], strerror (errno));
}
return 2;
}
#ifdef UMP_AGENT_DROP_ALL
lbs_logger_string (agent_log, "Configured to drop all kinds of packets");
#else
lbs_logger_string (agent_log, "Configured to drop only data packets");
#endif
unsigned long long pkt_recv = 0;
unsigned long long pkt_drop = 0;
while (!request_exit) {
UmpPkt pkt_struct;
UmpPkt* pkt = &pkt_struct;
struct sockaddr_storage src_struct;
struct sockaddr_storage* src = &src_struct;
socklen_t src_len = sizeof (struct sockaddr_storage);
ssize_t pkt_len = recvfrom (
udp_fd, pkt, UMP_PKT_SIZE, 0, SOCKADDR (src), &src_len);
if (pkt_len < 0) {
lbs_logger_format (agent_log, "recvfrom: %s", strerror (errno));
continue;
}
if (!ump_pkt_check_size (pkt, pkt_len)) {
lbs_logger_string (agent_log, "malformed header (dropped)");
continue;
}
ssize_t app_len = pkt_len - ump_pkt_get_data_offset (pkt);
pkt->app_data_len = app_len;
if (!ump_pkt_verify_checksum (pkt)) {
lbs_logger_string (agent_log, "invalid checksum (dropped)");
continue;
}
UmpApp* app_data = UMP_APP (ump_pkt_get_app_data (pkt));
if (!ump_app_check_size (app_data, app_len)) {
lbs_logger_format (agent_log, "malformed packet #%" PRIu32,
ump_pkt_get_seq_num (pkt));
continue;
}
char* pkt_msg = ump_pkt_show_message (pkt);
#ifndef UMP_AGENT_DROP_ALL
if (*pkt_msg != '[') {
#endif
if (rand () % loss_cycle == 0) {
pkt_recv++;
pkt_drop++;
lbs_logger_format (agent_log, "drop %s packet #%" PRIu32,
pkt_msg, ump_pkt_get_seq_num (pkt));
lbs_logger_format (agent_log, "loss rate = %.3lf",
(double)pkt_drop / (double)pkt_recv);
continue;
}
#ifndef UMP_AGENT_DROP_ALL
}
#endif
if (ump_app_fill_src_with_sockaddr (app_data, pkt, SOCKADDR (src)) < 0) {
lbs_logger_string (agent_log, "incompatible address (dropped)");
continue;
}
ump_pkt_fill_checksum (pkt);
struct sockaddr_storage dest_struct;
struct sockaddr_storage* dest = &dest_struct;
socklen_t dest_len;
memset (&dest_struct, 0, sizeof (dest_struct));
ump_app_fill_sockaddr_with_dest (
app_data, pkt, SOCKADDR (dest), &dest_len);
do_sendto:
if (sendto (udp_fd, pkt, pkt_len, 0, SOCKADDR (dest), dest_len) < 0) {
if (errno == EAGAIN || errno == EINTR) {
goto do_sendto;
}
lbs_logger_format (agent_log, "sendto: %s", strerror (errno));
continue;
}
lbs_logger_format (agent_log, "forward %s packet #%" PRIu32,
pkt_msg, ump_pkt_get_seq_num (pkt));
pkt_recv++;
}
lbs_logger_string (agent_log, "exited from processing loop (terminated)");
lbs_logger_destroy (agent_log);
return 0;
}
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