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/*
* Copyright (C) 2014-2019 Firejail Authors
*
* This file is part of firejail project
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <netdb.h>
#include <netinet/in.h>
#include <string.h>
int main(int argc, char **argv) {
int fd, newfd, client_len;
struct sockaddr_in serv_addr, client_addr;
int n, pid;
if (argc < 2) {
printf("Usage: ./server port-number\n");
return 1;
}
int portno = atoi(argv[1]);
// init socket
fd = socket(AF_INET, SOCK_STREAM, 0);
if (fd < 0) {
perror("ERROR opening socket");
return 1;
}
// Initialize socket structure
memset(&serv_addr, 0, sizeof(serv_addr));
serv_addr.sin_family = AF_INET;
serv_addr.sin_addr.s_addr = INADDR_ANY;
serv_addr.sin_port = htons(portno);
// bind
if (bind(fd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0) {
perror("bind");
return 1;
}
// listen - 5 pending conncections
if (listen(fd, 5) < 0) {
perror("listen");
return 1;
}
client_len = sizeof(client_addr);
while (1) {
newfd = accept(fd, (struct sockaddr *) &client_addr, &client_len);
if (newfd < 0) {
perror("accept");
return 1;
}
/* Create child process */
pid = fork();
if (pid < 0) {
perror("fork");
return 1;
}
if (pid == 0) {
// child
close(fd);
#define MAXBUF 4096
char buf[MAXBUF];
memset(buf, 0, MAXBUF);
int rcv = read(newfd, buf, MAXBUF - 1);
if (rcv < 0) {
perror("read");
exit(1);
}
int sent = write(newfd, "response\n", 9);
if (sent < 9) {
perror("write");
return 1;
}
exit(0);
}
else
close(newfd);
}
return 0;
}
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