lets see how it works:
after connected to the server you get a response number 220, the first thing you have to do after that is to send this
command:
HELO <domain>
its an announcement of identification that sent to the server and the server returns you response number 250 <name_of_the_host>
when name_of_the_host will be the name of the server that through it we send the mail.
Now you need to announce from which mail you sending it:
MAIL FROM:<reverse-path><CRLF>
CRLF for those who dont know is CR is '\r' and LF is '\n' ('\r' is end of line and '\n' start new line);
and then you get response number 250.
RCPT TO: <forward-path><CRLF>
to who you're sending the damn mail?
the response is 250 as usual.
of course you get 250 if everything goes well.
now the data of the mail comes here:
DATA<CRLF>
do not! :P dont change it! send it like that
and then you need to recieve 354 response. That says Start Mail Input
then
FROM:
This e-mail address is being protected from spam bots, you need JavaScript enabled to view it
<CRLF>
no response
Subject: Hello bud<CRLF>
no response
then you enter the contents of the mail :)
hey my name is c1pagr and im more cool then you are :)<CRLF>.<CRLF>
the point tells to the server thats all for now.
then you get response 250 OK
and then you need to enter
RSET<CRLF>
NOOP<CRLF>
QUIT<CRLF>
and to all of them you need to get response of 250 OK
QUIT tells the server cya!
NOOP clears the server buffers.
the responses from the server for each command:
S(Success),F(Failure),E(Eror)
CONNECTION ESTABLISHMENT
S: 220
F: 421
HELO
S: 250
E: 500, 501, 504, 421
MAIL S: 250
F: 552, 451, 452
E: 500, 501, 421
RCPT
S: 250, 251
F: 550, 551, 552, 553, 450, 451, 452
E: 500, 501, 503, 421
DATA
I: 354 -> data -> S: 250
F: 552, 554, 451, 452
F: 451, 554
E: 500, 501, 503, 421
RSET
S: 250
E: 500, 501, 504, 421
NOOP
S: 250
E: 500, 421
QUIT
S: 221
E: 500
Code in C:
//after connecting to the server ...
char*recvbuf = (char *)maloc(sizeof(char)*256);
char*recvbuf_tmp = (char *)maloc(sizeof(char)*256);
charsendbuf[256]= "";
int er =0;
recv(msock,recvbuf_tmp,256,0);
Sleep(500);
if(*(recvbuf_tmp)=='4'| *(recvbuf_tmp)=='5')
{
er =1;
}
if(*(recvbuf_tmp)=='2'&&*(recvbuf_tmp+1)=='2'&&*(recvbuf_tmp+2)=='0' && er==0)
{
puts(recvbuf_tmp);
}
strcpy(sendbuf,"HELO ");
strcat(sendbuf,"bezeqint.net\r\n");
send(msock,sendbuf,strlen(sendbuf),0);
Sleep(500);
recv(msock,recvbuf,256,0);
if(*(recvbuf)=='2' &&*(recvbuf+1)=='5' && *(recvbuf+2)== '0' && er==0)
{
strcpy(sendbuf, "MAIL FROM:<
This e-mail address is being protected from spam bots, you need JavaScript enabled to view it
>\r\n");
send(msock,sendbuf,strlen(sendbuf),0);
Sleep(500);
recv(msock,recvbuf_tmp,256,0);
}
if(*recvbuf_tmp=='4' | *recvbuf_tmp=='5')
{
er=1;
}
if(*recvbuf_tmp=='2' && *(recvbuf_tmp+1)=='5'&& *(recvbuf_tmp+2)=='0'&& er == 0)
{
puts(recvbuf);
putchar('\n');
strcpy(sendbuf, "RCPT TO:<
This e-mail address is being protected from spam bots, you need JavaScript enabled to view it
>\r\n");
send(msock,sendbuf,strlen(sendbuf),0);
Sleep(500);
recv(msock,recvbuf_tmp,256,0);
}
if(*(recvbuf_tmp)=='2' &&*(recvbuf_tmp+1)=='5' &&*(recvbuf_tmp+2)=='0' &&er==0)
{
strcpy(sendbuf,"DATA\r\n\r\n");
send(msock,sendbuf,strlen(sendbuf),0);
Sleep(500);
recv(msock,recvbuf_tmp,256,0);
}
if(*(recvbuf_tmp)=='4' |*(recvbuf_tmp)=='5')
{
er=1;
}
if(*(recvbuf_tmp)=='3' &&*(recvbuf_tmp+1)=='5' &&*(recvbuf_tmp+2)=='4' &&er==0)
{
puts(recvbuf_tmp);
printf("\n\nstartingwith sendingdata: \n");
putchar('\n');
strcpy(sendbuf, "From: <");
strcat(sendbuf,"blabla"); / (: send(msock,sendbuf,strlen(sendbuf),0);
Sleep(500);
//here you copy the contents to the buffer and send it on the next line :)
strcpy(sendbuf, "Thisisa virus! andwe don'twant peace\x0d\x0a.\x0d\x0a"); /
send(msock,sendbuf,strlen(sendbuf),0);
Sleep(500);
recv(msock,recvbuf_tmp,256,0);
}
if(*recvbuf_tmp=='5' | *recvbuf_tmp=='4')
{
er =1;
printf("\ncan't send data");
}
if(*(recvbuf_tmp)== '2' && *(recvbuf_tmp+1)=='5' && *(recvbuf_tmp+2)=='0' && er==0)
{
printf("\n\n\n\nSENDED.\n\n");
}
strcpy(sendbuf,"QUIT\x0d\x0a");
send(msock,sendbuf,strlen(sendbuf),0);
printf("Closing connection .finished with sex:) \n\n");
getchar();
}
hope you learned something new
yours forever,
c1pagr
(use it wwwize :P )
