/* CGI program to read email from a pop server (port 110). */ #include #include #include #include #include #include #include #include #include #include #include extern int errno; /* Error codes are returned here. */ struct hostent *hostent; struct sockaddr_in sockaddr; int sock,status,hostaddr,pop3_port=110,socket_option=0; time_t current_time,hold_time; char buffer[4096]; fd_set socket_read_status; struct timeval socket_time_structure; #define TIMEOUT_SECONDS 30 char pop3_server[128],pop3_account[32],pop3_password[32]; char temp_string[128],form_data_string[255]; int message_number,temp_int,temp_string_pointer; char message_number_string[8],byte_count_string[8]; int byte_count,byte_count_string_pointer,message_bytes_read,extra_bytes_read; /*----------------------------- Subroutines ----------------------------------*/ #include "web_based_email.h" int list_messages_and_sizes(void) { /* Get the results of the LIST command for display. */ printf("

List of messages and their sizes (in bytes):\n"); printf("

\n");
strcpy(buffer,"LIST");
strcat(buffer,"\r\n");
write(sock,buffer,strlen(buffer));
strcpy(temp_string,"");
while (strcmp(temp_string,"."))
  {
  if (get_message_from_socket())
    {
    printf("Error getting LIST response from POP3 server.\n");
    printf("

\n"); shutdown(sock,2); close(sock); return(1); } if ((strcmp(temp_string,".")) && (strcmp(temp_string,"+OK"))) printf("%s\n",temp_string); } printf("\n"); return(0); } /*----------------------------- Main Program ---------------------------------*/ int main(void) { printf("Content-type: text/html\n"); /* We have to return this line first. */ printf("\n"); printf("\n"); printf("\n"); printf("

POP3 Session Results

\n"); printf("\n"); printf("\n"); gets(form_data_string); /* Get form data. */ temp_int = 0; while (form_data_string[temp_int]) { if (form_data_string[temp_int] == '+') form_data_string[temp_int] = ' '; temp_int++; } /* Figure out POP3 information and load variables. */ find_field_in_form_data_string("pop3_server"); strcpy(pop3_server,temp_string); find_field_in_form_data_string("pop3_account"); strcpy(pop3_account,temp_string); find_field_in_form_data_string("pop3_password"); strcpy(pop3_password,temp_string); /* Now get connected. */ strcpy(temp_string,pop3_server); hostent = gethostbyname(temp_string); /* Do DNS lookup. */ if (hostent == NULL) { printf("Couldn't resolve POP3 server address; quitting.\n"); goto exit_program; } sock = socket(AF_INET,SOCK_STREAM,0); /* Allocate a socket. */ if (sock < 0) { printf("Unable to allocate a socket; quitting.\n"); goto exit_program; } /* Initialize sockaddr fields. */ memset(&sockaddr,0,sizeof(sockaddr)); sockaddr.sin_family = AF_INET; memcpy((char *)&(sockaddr.sin_addr.s_addr),(char *)hostent->h_addr_list[0], (size_t)hostent->h_length); sockaddr.sin_port = htons(pop3_port); /* Connect to remote port now. */ if (connect(sock,(struct sockaddr *)&sockaddr,sizeof(sockaddr)) < 0) { printf("Unable to connect to your POP3 server; quitting.\n"); close(sock); goto exit_program; } fcntl(sock,F_SETFL,O_NONBLOCK); /* Set socket to non-blocking. */ /*-------------------------------------*/ /* Now we're ready to talk with the pop3 server, with text messages. */ /* Get welcome message from server. */ if (get_message_from_socket()) { printf("Didn't get welcome message from POP3 server; quitting.\n"); goto shut_down_and_close; } if (strncmp(temp_string,"+OK",3)) /* Not ok? */ { printf("Bad welcome message from server: %s\n",temp_string); goto shut_down_and_close; } strcpy(buffer,"USER "); strcat(buffer,pop3_account); strcat(buffer,"\r\n"); write(sock,buffer,strlen(buffer)); if (get_message_from_socket()) { printf("Error getting USER response from POP3 server.\n"); goto shut_down_and_close; } if (strncmp(temp_string,"+OK",3)) /* Not ok? */ { printf("Bad name response from server: %s\n",temp_string); goto shut_down_and_close; } strcpy(buffer,"PASS "); strcat(buffer,pop3_password); strcat(buffer,"\r\n"); write(sock,buffer,strlen(buffer)); if (get_message_from_socket()) { printf("Error getting PASS response from POP3 server.\n"); goto shut_down_and_close; } if (strncmp(temp_string,"+OK",3)) /* Didn't get +OK? */ { printf("Bad password response from server; quitting.\n"); goto shut_down_and_close; } printf("

\n"); printf("Login message: %s\n",temp_string); if (list_messages_and_sizes()) goto shut_down_and_close; /*--------------------*/ message_number = 0; while (1) { message_number++; sprintf(message_number_string,"%d",message_number); strcpy(buffer,"LIST "); /* Find out how many bytes the message has. */ strcat(buffer,message_number_string); strcat(buffer,"\r\n"); write(sock,buffer,strlen(buffer)); if (get_message_from_socket()) { printf("Timeout getting LIST response; quitting.\n"); goto shut_down_and_close; } if (strncmp(temp_string,"+OK",3)) /* No such message? */ break; temp_string_pointer = 4; /* Point to 1st digit of message number in result string. */ while (temp_string[temp_string_pointer++] != ' ') /* Skip to start of byte count. */ { } byte_count_string_pointer = 0; while (1) { if (temp_string[temp_string_pointer] == 10) break; if (temp_string[temp_string_pointer] == 13) break; if (temp_string[temp_string_pointer] == 0) break; byte_count_string[byte_count_string_pointer++] = temp_string[temp_string_pointer++]; } byte_count_string[byte_count_string_pointer] = 0; /* Terminate. */ byte_count = atoi(byte_count_string); printf("

\n"); printf("

Message %d (%d bytes):

\n",message_number,byte_count); strcpy(buffer,"RETR "); /* Ask the mail server for the message. */ strcat(buffer,message_number_string); strcat(buffer,"\r\n"); write(sock,buffer,strlen(buffer)); if (get_message_from_socket()) /* Get response. */ { printf("Timeout after RETR %d command; quitting.\n",message_number); goto shut_down_and_close; } if (strncmp(temp_string,"+OK",3)) /* Problem, or invalid message? */ { printf("Unable to RETR after a successful LIST %d.\n",message_number); goto shut_down_and_close; } printf("

\n");
  printf("\n");

  message_bytes_read = 0;
  hold_time = time((time_t *) 0);
  while (message_bytes_read < byte_count)  /* Read and print email message. */
    {
    current_time = time((time_t *) 0);
    if (current_time - hold_time > TIMEOUT_SECONDS)
      {
      printf("POP3 timeout while printing message; quitting.\n");
      break;
      }
    if (read(sock,buffer,1) != 1)  /* Try to read just one character. */
      {
      sleep(1);
      continue;
      }
    hold_time = time((time_t *) 0);  /* Reset timer in case message is long. */
    message_bytes_read++;
    if (isprint(buffer[0]) || (buffer[0]==10) || (buffer[0]==13))  /* Avoid messing up the screen. */
      printf("%c",buffer[0]);  /* Print the character we received. */
    }
  fflush(stdout);

  extra_bytes_read = 0;
  hold_time = time((time_t *) 0);  /* Trash anything else for 5 seconds. */
  while (1)
    {
    current_time = time((time_t *) 0);
    if (current_time - hold_time > 5)
      break;
    if (read(sock,buffer,1) != 1)
      {
      sleep(1);
      continue;
      }
    if (++extra_bytes_read == 3)
      break;
    }

  printf("

\n"); /* Go back for another message. */ } if (list_messages_and_sizes()) goto shut_down_and_close; /*--------------------*/ /* Now log out from the pop3 server. */ strcpy(buffer,"QUIT\r\n"); write(sock,buffer,strlen(buffer)); if (get_message_from_socket()) { printf("Error getting QUIT response from pop3 server.\n"); goto shut_down_and_close; } if (strncmp(temp_string,"+OK",3)) printf("POP3 QUIT response was: %s\n",temp_string); if (message_number == 1) /* No messages on file? */ { printf("

\n"); printf("

There were no messages waiting.

\n"); goto shut_down_and_close; } /* Produce the form here for message deletion. */ printf("

Enter message numbers to delete, separated by spaces.
\n"); printf("\n"); /*-------------------------------------*/ shut_down_and_close: shutdown(sock,2); close(sock); exit_program: printf("

\n"); printf("Please send any comments on this web-based email system to\n"); printf("Alton Moore.\n"); printf("\n"); printf("\n"); return(0); }