2023-09-30 14:28:48 -05:00
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//----- Include files ---------------------------------------------------------
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#include <stdio.h> // Needed for printf()
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#include <stdlib.h> // Needed for exit()
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#include <string.h> // Needed for strcpy() and strlen()
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#include <fcntl.h> // Needed for file i/o constants
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#include <sys/stat.h> // Needed for file i/o constants
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#include <future>
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#include <sys/types.h> //
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#include <netinet/in.h> //
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#include <sys/socket.h> //
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#include <arpa/inet.h> //
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#include <unistd.h>
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//----- HTTP response messages ----------------------------------------------
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#define OK_IMAGE "HTTP/1.0 200 OK\nContent-Type:image/gif\n\n"
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#define OK_TEXT "HTTP/1.0 200 OK\nContent-Type:text/html\n\n"
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#define NOTOK_404 "HTTP/1.0 404 Not Found\nContent-Type:text/html\n\n"
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#define MESS_404 "<html><body><h1>FILE NOT FOUND</h1></body></html>"
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//----- Defines -------------------------------------------------------------
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#define BUF_SIZE 4096 // Buffer size (big enough for a GET)
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2023-09-30 17:13:09 -05:00
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#define PORT_NUM 9080 // Port number for a Web server
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2023-09-30 14:28:48 -05:00
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//----- Function prototypes -------------------------------------------------
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2023-09-30 17:13:09 -05:00
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void BrowserToProxy(int server_s, int client_s);
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void ProxyToServer(int server_s, int client_s);
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2023-09-30 14:28:48 -05:00
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//===== modeule main ========================================================
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int main(void)
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{
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2023-09-30 17:13:09 -05:00
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unsigned int proxy_s; // Server socket descriptor
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struct sockaddr_in proxy_addr; // Server Internet address
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unsigned int browser_s; // Client socket descriptor
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struct sockaddr_in browser_addr; // Client Internet address
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struct in_addr browser_ip_addr; // Client IP address
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unsigned int server_s; // Client socket descriptor
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struct sockaddr_in server_addr; // Client Internet address
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struct in_addr server_ip_addr; // Client IP address
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2023-09-30 14:28:48 -05:00
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socklen_t addr_len; // Internet address length
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// Create a socket, fill-in address information, and then bind it
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proxy_s = socket(AF_INET, SOCK_STREAM, 0);
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if (proxy_s == -1)
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2023-09-30 14:28:48 -05:00
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{
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printf("ERROR - Unable to create socket on server\n");
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exit(1);
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}
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2023-09-30 17:13:09 -05:00
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proxy_addr.sin_family = AF_INET;
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proxy_addr.sin_port = htons(PORT_NUM);
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proxy_addr.sin_addr.s_addr = htonl(INADDR_ANY);
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int bindRet = bind(proxy_s, (struct sockaddr *)&proxy_addr, sizeof(proxy_addr));
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if (bindRet == -1)
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{
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printf("ERROR - Unable to bind socket\n");
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exit(1);
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}
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// Listen for connections and then accept
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listen(proxy_s, 100);
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// Main loop to listen, accept, and then spin-off a thread to handle the GET
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while (1)
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{
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addr_len = sizeof(browser_addr);
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browser_s = accept(proxy_s, (struct sockaddr *)&browser_addr, &addr_len);
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if (browser_s == -1)
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{
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perror("ERROR - Unable to create socket to client\n");
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continue;
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}
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unsigned int server_s = socket(AF_INET, SOCK_STREAM, 0);
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connect(server_s, (struct sockaddr *)&server_addr, addr_len);
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2023-09-30 17:13:09 -05:00
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std::async(std::launch::async, BrowserToProxy, browser_s, server_s);
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std::async(std::launch::async, ProxyToServer, server_s, browser_s);
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2023-09-30 14:28:48 -05:00
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}
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close(browser_s);
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return (1);
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}
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2023-09-30 17:13:09 -05:00
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void BrowserToProxy(int server_s, int client_s) {
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char in_buf[BUF_SIZE]; // Input buffer for GET resquest
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char out_buf[BUF_SIZE]; // Output buffer for HTML response
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char *file_name; // File name
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unsigned int fh; // File handle
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ssize_t buf_len; // Buffer length for file reads
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unsigned int retcode; // Return code
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// Receive the GET request from the Web browser
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do {
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buf_len = recv(server_s, in_buf, BUF_SIZE, 0);
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send(client_s, in_buf, buf_len, 0);
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} while (buf_len != 0);
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2023-09-30 14:28:48 -05:00
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}
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2023-09-30 17:13:09 -05:00
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void ProxyToServer(int server_s, int client_s) {
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/*
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loop {
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recv from browser
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send to server
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}
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2023-09-30 14:28:48 -05:00
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2023-09-30 17:13:09 -05:00
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*/
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2023-09-30 14:28:48 -05:00
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char in_buf[BUF_SIZE]; // Input buffer for GET resquest
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char out_buf[BUF_SIZE]; // Output buffer for HTML response
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char *file_name; // File name
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unsigned int fh; // File handle
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ssize_t buf_len; // Buffer length for file reads
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unsigned int retcode; // Return code
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2023-09-30 14:28:48 -05:00
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// Receive the GET request from the Web browser
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do {
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buf_len = recv(server_s, in_buf, BUF_SIZE, 0);
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send(client_s, in_buf, buf_len, 0);
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} while (buf_len != 0);
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close(server_s);
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close(client_s);
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2023-09-30 14:28:48 -05:00
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}
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