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#ifdef _WIN32
#include <ws2tcpip.h>
#include <windows.h>
#endif
#include <stdlib.h>
#include <stdio.h>
#include <sys/types.h>
#ifndef _WIN32
#include <sys/socket.h>
#include <sys/wait.h>
#include <netinet/in.h>
#endif
#include <string.h>
#include <unistd.h>
#define MAXLINE 1024
#define BUFLEN 256
#define SERV_PORT 3000
#define LISTENQ 8
int exploitable(int fd)
{
int n;
char buf[BUFLEN];
memset(buf, 0, BUFLEN);
if (buf[0] == EOF) {
return (0);
}
n = recv(fd, buf, MAXLINE, 0);
fprintf(stderr, "Received string(%d): %s", n, buf);
return (n);
}
int main (int argc, char **argv)
{
int listenfd, connfd, n;
socklen_t clilen;
struct sockaddr_in cliaddr, servaddr;
if ((listenfd = socket(AF_INET, SOCK_STREAM, 0)) <0) {
perror("socket");
exit(1);
}
servaddr.sin_family = AF_INET;
servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
servaddr.sin_port = htons(SERV_PORT);
if (bind(listenfd, (struct sockaddr *) &servaddr, sizeof(servaddr)) != 0) {
perror("bind");
exit(2);
}
if (listen(listenfd, LISTENQ) != 0) {
perror("listen");
exit(3);
}
fprintf(stderr, "Server running on port %d ...\n", SERV_PORT);
for (;;) {
clilen = sizeof(cliaddr);
connfd = accept(listenfd, (struct sockaddr *) &cliaddr, &clilen);
if (connfd < 0) break;
fprintf(stderr, "Client connected.\n");
while ((n = exploitable(connfd)) > 0) {
}
fprintf(stderr, "disconnecting client ..\n");
close(connfd);
}
fprintf(stderr, "shutdown ..\n");
close(listenfd);
return (0);
}
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