Email attachment via smtp - how?!

I'm writing a keylogger function and need to email the log to the admin-specified email address programmatically.

Sending a simple text message via smtp is easy enough, but how do you attach a file to an email message? I can't seem to find any examples. If you have any knowledge, please fill me in.

Thanks a bunch.

Let's say you want to send a simple text file (details.txt) as an attachment. You could use this:

Code:

   // send these:
   // HELO 
   // MAIL FROM: 
   // RCPT TO: 
   // DATA

   // now send MIME-version
   sprintf( buf, "MIME-Version: 1.0" );
   send( socket, buf );

   // Send the Content-Type: multipart/mixed;
   sprintf( buf, "Content-Type: multipart/mixed;" );
   send( socket, buf );

   // send the Content-Transfer-Encoding: quoted-printable 
   sprintf( buf, "Content-Transfer-Encoding: quoted-printable" );
   send( socket, buf );
   
   // send the Content-Type: text/plain; 
   sprintf( buf, "Content-Type: text/plain;" );
   send( socket, buf );

   // send the name="details.txt" 
   sprintf( buf, "    name=\"details.txt\" " );
   send( socket, buf);

   // send the Content-Disposition: attachment; 
   sprintf( buf, "Content-Disposition: attachment;" );
   send( socket, buf);

   // send a blank line first !
   sprintf( buf, "\r\n" );
   send( socket, buf);

   // now, get the attachment contents and send them
   // line by line.
   
   MailFilePtr = fopen( AttachmentFile, "r" );
   if ( MailFilePtr == NULL )
   {
       // handle error
   }

   memset( FileBuffer, 0, sizeof(FileBuffer) );
   while ( fgets (FileBuffer, sizeof( FileBuffer), MailFilePtr) )
   {
      sprintf( buf, "%s", FileBuffer );
      buf[strlen(buf)- 1] = 0;
      send( socket, buf );
      memset( FileBuffer, 0, sizeof(FileBuffer) );
      memset( buf, 0, sizeof(buf) );
   }
   
   fclose( MailFilePtr );

   sprintf( buf, "\r\n");
   send( socket, buf );

This should work. Hope this helps.

Thanks a bunch Ruchikar. Big help.

Just needed to know what commands to send. I also just found an example that uses 'boundary'

I appreciate it.