// SPDX-License-Identifier: GPL-2.0

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>

int main(int argc, char *argv[])
{
        struct sockaddr_in saddr = {}, daddr = {};
        socklen_t len = sizeof(daddr);
        struct timeval tv = {25, 0};
        char buf[] = "hello";
        int sd, ret;

        if (argc != 6 || (strcmp(argv[1], "server") && strcmp(argv[1], "client"))) {
                printf("%s <server|client> <LOCAL_IP> <LOCAL_PORT> <REMOTE_IP> <REMOTE_PORT>\n",
                       argv[0]);
                return -1;
        }

        sd = socket(AF_INET, SOCK_SEQPACKET, IPPROTO_SCTP);
        if (sd < 0) {
                printf("Failed to create sd\n");
                return -1;
        }

        saddr.sin_family = AF_INET;
        saddr.sin_addr.s_addr = inet_addr(argv[2]);
        saddr.sin_port = htons(atoi(argv[3]));

        ret = bind(sd, (struct sockaddr *)&saddr, sizeof(saddr));
        if (ret < 0) {
                printf("Failed to bind to address\n");
                goto out;
        }

        ret = listen(sd, 5);
        if (ret < 0) {
                printf("Failed to listen on port\n");
                goto out;
        }

        daddr.sin_family = AF_INET;
        daddr.sin_addr.s_addr = inet_addr(argv[4]);
        daddr.sin_port = htons(atoi(argv[5]));

        /* make test shorter than 25s */
        ret = setsockopt(sd, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv));
        if (ret < 0) {
                printf("Failed to setsockopt SO_RCVTIMEO\n");
                goto out;
        }

        if (!strcmp(argv[1], "server")) {
                sleep(1); /* wait a bit for client's INIT */
                ret = connect(sd, (struct sockaddr *)&daddr, len);
                if (ret < 0) {
                        printf("Failed to connect to peer\n");
                        goto out;
                }
                ret = recvfrom(sd, buf, sizeof(buf), 0, (struct sockaddr *)&daddr, &len);
                if (ret < 0) {
                        printf("Failed to recv msg %d\n", ret);
                        goto out;
                }
                ret = sendto(sd, buf, strlen(buf) + 1, 0, (struct sockaddr *)&daddr, len);
                if (ret < 0) {
                        printf("Failed to send msg %d\n", ret);
                        goto out;
                }
                printf("Server: sent! %d\n", ret);
        }

        if (!strcmp(argv[1], "client")) {
                usleep(300000); /* wait a bit for server's listening */
                ret = connect(sd, (struct sockaddr *)&daddr, len);
                if (ret < 0) {
                        printf("Failed to connect to peer\n");
                        goto out;
                }
                sleep(1); /* wait a bit for server's delayed INIT_ACK to reproduce the issue */
                ret = sendto(sd, buf, strlen(buf) + 1, 0, (struct sockaddr *)&daddr, len);
                if (ret < 0) {
                        printf("Failed to send msg %d\n", ret);
                        goto out;
                }
                ret = recvfrom(sd, buf, sizeof(buf), 0, (struct sockaddr *)&daddr, &len);
                if (ret < 0) {
                        printf("Failed to recv msg %d\n", ret);
                        goto out;
                }
                printf("Client: rcvd! %d\n", ret);
        }
        ret = 0;
out:
        close(sd);
        return ret;
}