loginwindow.cpp  smtp.cpp                                                                                                                                                                     X
  1 #include<iostream> 
  2 #include <sys/types.h> 
  3 #include <sys/socket.h> 
  4 #include <netinet/in.h> 
  5 #include <netdb.h> 
  6 #include <stdio.h> 
  7 #include<cstring> 
  8 #include<unistd.h> 
  9 #include<cstdlib> 
 10  
 11 using namespace std; 
 12 #define HELO "HELO smtp.gmail.com\r\n" 
 13 #define DATA "DATA\r\n" 
 14 #define QUIT "QUIT\r\n" 
 15  
 16 //#define h_addr h_addr_list[0] 
 17 //FILE *fin; 
 18 int sock; 
 19 struct sockaddr_in server; 
 20 struct hostent *hp, *gethostbyname(); 
 21 char buf[BUFSIZ+1]; 
 22 int len; 
 23 char *host_id="smtp.gmail.com";  //192.168.1.10"; 
 24 char *from_id="[email protected]"; 
 25 char *to_id="[email protected]"; 
 26 char *sub="testmail\r\n"; 
 27 char wkstr[100]="hello how r u\r\n"; 
 28  
 29 /*=====Send a string to the socket=====*/ 
 30  
 31 void send_socket(char *s) 
 32 { 
 33         write(sock,s,strlen(s)); 
 34         write(1,s,strlen(s)); 
 35         //printf("Client:%s\n",s); 
 36 } 
 37  
 38 //=====Read a string from the socket=====*/ 
 39  
 40 void read_socket() 
 41 { 
 42         len = read(sock,buf,BUFSIZ); 
 43         write(1,buf,len); 
 44         //printf("Server:%s\n",buf); 
 45 } 
 46  
/*=====MAIN=====*/
 48 int main(int argc, char* argv[])
 49 {
 50         /*=====Create Socket=====*/
 51         sock = socket(AF_INET, SOCK_STREAM, 0);
 52 
 53         if (sock==-1)
 54         {
 55                 perror("opening stream socket");
 56                 exit(1);
 57         }
 58         else
 59                 cout << "socket created\n";
 60 
 61         /*=====Verify host=====*/
 62         server.sin_family = AF_INET;
 63         cout<<"About to call gethost ... \n";
 64         hp = gethostbyname(host_id);
 65 
 66         cout<<"Return from gethost ... "<< hp<<"\n";
 67         if (hp==(struct hostent *) 0)
 68         {
 69                 fprintf(stderr, "%s: unknown host\n", host_id);
 70                 exit(2);
 71         }
 72         cout<<"Trying to connect to remote host\n";
 73 
 74         /*=====Connect to port 25 on remote host=====*/
 75         memcpy((char *) &server.sin_addr, (char *) hp->h_addr, hp->h_length);
 76 
 77         server.sin_port=htons(25); /* SMTP PORT */
 78 
 79         cout<<"Trying to connect to remote host now\n";
 80         if (connect(sock, (struct sockaddr *) &server, sizeof server)==-1)
 81         {
 82                 perror("connecting stream socket");
 83                 exit(1);
 84         }
 85         else
 86                 cout << "Connected\n";
 87 
 88         /*=====Write some data then read some =====*/
 89         read_socket(); /* SMTP Server logon string */
 90         send_socket("STARTTLS\n");
 91         read_socket(); /*Read reply */
 93         send_socket(HELO); /* introduce ourselves */
 94         read_socket(); /*Read reply */
 95 
 96         send_socket("STARTTLS\n");
 97 
 98         send_socket("MAIL FROM: ");
 99         send_socket(from_id);
100         send_socket("\r\n");
101         read_socket(); /* Sender OK */
102         send_socket("VRFY ");
103         send_socket(from_id);
104         send_socket("\r\n");
105         read_socket(); // Sender OK */
106         send_socket("RCPT TO: "); /*Mail to*/
107         send_socket(to_id);
108         send_socket("\r\n");
109         read_socket(); // Recipient OK*/
110         send_socket(DATA);// body to follow*/
111         send_socket("Subject: ");
112         send_socket(sub);
113         read_socket(); // Recipient OK*/
114         send_socket(wkstr);
115         send_socket(".\r\n");
116         read_socket();
117         send_socket(QUIT); /* quit */
118         read_socket(); // log off */
119 
120         //=====Close socket and finish=====*/
121         close(sock);
122         exit(0);
123 }