Files
CSE4303H3/client.cpp
2026-03-02 21:20:12 -06:00

130 lines
3.7 KiB
C++

#include <stdio.h>
#include <string.h>
#include <sys/socket.h>
#include <arpa/inet.h>
// open ssl
#include <openssl/conf.h>
#include <openssl/evp.h>
#include <openssl/err.h>
#include <errno.h> // error handling
#include <unistd.h> // for close()
#include <string>
#include <cstring>
#include <cstdlib> // for atoi()
#include <vector>
#include "helper.h"
int main(void)
{
load_env(".env");
// Declare variables
const char *server_ip = std::getenv("SERVER_IP");
const int server_port = std::atoi(std::getenv("SERVER_PORT"));
printf("Connecting to server %s:%d\n", server_ip, server_port);
char client_message[1024];
char server_message[1024];
const char *custom_message = "Zheyuan Wu: ";
// Create socket:
int client_socket = socket(AF_INET, SOCK_STREAM, 0);
if (client_socket == -1)
{
perror("Failed to create socket");
return 1;
}
else
{
printf("Socket created successfully\n");
}
// Send connection request to server, be sure to set por tand IP the same as server-side
struct sockaddr_in server_addr;
server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(server_port);
inet_pton(AF_INET, server_ip, &server_addr.sin_addr);
if (connect(client_socket, (struct sockaddr *)&server_addr, sizeof(server_addr)) == -1)
{
perror("Failed to connect to server");
close(client_socket);
return 1;
}
else
{
printf("Connected to server successfully\n");
}
// Get input from the user:
printf("Enter message sent to the server (type \\quit to exit): ");
// clean the buffer
memset(client_message, 0, sizeof(client_message));
if (fgets(client_message, sizeof(client_message), stdin) == NULL)
{
// EOF or error reading from stdin, exit the loop
perror("Error reading from stdin");
return 1;
}
while (strcmp(client_message, "\\quit\n") != 0)
{
// Send the message to server:
// add my name in the front
char buffer[2048];
std::snprintf(buffer, sizeof(buffer), "%s%s", custom_message, client_message);
printf("Message sent to server: %s, length: %d \n", byte_to_hex((unsigned char *)buffer, strlen(buffer)), (int)strlen(buffer));
ssize_t sent = send(client_socket, buffer, strlen(buffer), 0);
if (sent <= 0)
{
perror("No message sent to server");
break;
}
// send hmac of the message
unsigned char hmac[20];
memset(hmac, 0, sizeof(hmac));
cal_hmac(hmac, buffer);
printf("HMAC sent to server: %s\n", byte_to_hex(hmac, 20));
ssize_t sent_hmac = send(client_socket, hmac, strlen((char *)hmac), 0);
if (sent_hmac <= 0) {
perror("No HMAC sent to server");
break;
}
// Receive the server's response:
// add terminator for string
ssize_t recvd = recv(client_socket, server_message, sizeof(server_message) - 1, 0);
if (recvd <= 0)
{
perror("No message received from server");
break;
}
server_message[recvd] = '\0';
printf("Server's response: %s\n", server_message);
printf("Enter message sent to the server (type \\quit to exit): ");
// clean the buffer
memset(client_message, 0, sizeof(client_message));
memset(server_message, 0, sizeof(server_message));
if (fgets(client_message, sizeof(client_message), stdin) == NULL)
{
// EOF or error reading from stdin, exit the loop
perror("Error reading from stdin");
break;
}
}
// Close the socket
close(client_socket);
return 0;
}