/*
*
* Copyright (c) 2011-2016 The University of Waikato, Hamilton, New Zealand.
* All rights reserved.
*
* This file is part of libprotoident.
*
* This code has been developed by the University of Waikato WAND
* research group. For further information please see http://www.wand.net.nz/
*
* libprotoident is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* libprotoident is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see .
*
*
*/
#include
#include "libprotoident.h"
#include "proto_manager.h"
#include "proto_common.h"
static inline bool match_smtp_command(uint32_t payload, uint32_t len) {
if (MATCHSTR(payload, "EHLO"))
return true;
if (MATCHSTR(payload, "ehlo"))
return true;
if (MATCHSTR(payload, "HELO"))
return true;
if (MATCHSTR(payload, "helo"))
return true;
if (MATCHSTR(payload, "NOOP"))
return true;
if (MATCHSTR(payload, "XXXX"))
return true;
if (MATCHSTR(payload, "HELP"))
return true;
if (MATCHSTR(payload, "EXPN"))
return true;
/* Turns out there are idiots who send their ehlos one byte at a
* time :/ */
if (MATCH(payload, 'e', 0x00, 0x00, 0x00) && len == 1)
return true;
if (MATCH(payload, 'E', 0x00, 0x00, 0x00) && len == 1)
return true;
if (MATCH(payload, 'h', 0x00, 0x00, 0x00) && len == 1)
return true;
if (MATCH(payload, 'H', 0x00, 0x00, 0x00) && len == 1)
return true;
return false;
}
static inline bool match_smtp_banner(uint32_t payload, uint32_t len) {
/* Stupid servers that only send the banner one or two bytes at
* a time! */
if (len == 1) {
if (MATCH(payload, '2', 0x00, 0x00, 0x00))
return true;
return false;
}
if (len == 2) {
if (MATCH(payload, '2', '2', 0x00, 0x00))
return true;
return false;
}
if (len == 3) {
if (MATCH(payload, '2', '2', '0', 0x00))
return true;
return false;
}
if (MATCH(payload, '2', '2', '0', ' '))
return true;
if (MATCH(payload, '2', '2', '0', '-'))
return true;
return false;
}
static inline bool invalid_smtp(lpi_data_t *data) {
if (data->payload_len[0] == 0 || data->payload_len[1] == 0)
{
if (match_str_either(data, "220 ") &&
(data->server_port == 21 ||
data->client_port == 21))
return true;
}
return false;
}
static inline bool match_smtp(lpi_data_t *data, lpi_module_t *mod UNUSED)
{
if(invalid_smtp(data))
{
return false;
}
/* Match all the random error codes */
if (data->payload_len[0] == 0 || data->payload_len[1] == 0) {
if (match_str_either(data, "220 "))
return true;
if (match_str_either(data, "450 "))
return true;
if (match_str_either(data, "550 "))
return true;
if (match_str_either(data, "550-"))
return true;
if (match_str_either(data, "421 "))
return true;
if (match_str_either(data, "421-"))
return true;
if (match_str_either(data, "451 "))
return true;
if (match_str_either(data, "451-"))
return true;
if (match_str_either(data, "452 "))
return true;
if (match_str_either(data, "420 "))
return true;
if (match_str_either(data, "571 "))
return true;
if (match_str_either(data, "553 "))
return true;
if (match_str_either(data, "554 "))
return true;
if (match_str_either(data, "554-"))
return true;
if (match_str_either(data, "476 "))
return true;
if (match_str_either(data, "475 "))
return true;
}
if (match_str_either(data, "QUIT") &&
(data->server_port == 25 ||
data->server_port == 587 ||
data->client_port == 25 ||
data->client_port == 587)
)
return true;
if (match_str_either(data, "quit") &&
(data->server_port == 25 ||
data->server_port == 587 ||
data->client_port == 25 ||
data->client_port == 587)
)
return true;
if (match_str_either(data, "Quit") &&
(data->server_port == 25 ||
data->server_port == 587 ||
data->client_port == 25 ||
data->client_port == 587)
)
return true;
if (match_str_either(data, "EHLO") &&
(data->server_port == 25 ||
data->server_port == 587 ||
data->client_port == 25 ||
data->client_port == 587)
)
return true;
if (match_str_either(data, "ehlo") &&
(data->server_port == 25 ||
data->server_port == 587 ||
data->client_port == 25 ||
data->client_port == 587)
)
return true;
if (match_str_either(data, "HELO") &&
(data->server_port == 25 ||
data->server_port == 587 ||
data->client_port == 25 ||
data->client_port == 587)
)
return true;
if (match_str_either(data, "helo") &&
(data->server_port == 25 ||
data->server_port == 587 ||
data->client_port == 25 ||
data->client_port == 587)
)
return true;
if (match_str_either(data, "MAIL") &&
(data->server_port == 25 ||
data->server_port == 587 ||
data->client_port == 25 ||
data->client_port == 587)
)
return true;
if (match_str_either(data, "mail") && (data->server_port == 25 ||
data->server_port == 587 ||
data->client_port == 25 ||
data->client_port == 587))
return true;
if (match_str_either(data, "RCPT") &&
(data->server_port == 25 ||
data->server_port == 587 ||
data->client_port == 25 ||
data->client_port == 587)
)
return true;
if (match_str_either(data, "rcpt") &&
(data->server_port == 25 ||
data->server_port == 587 ||
data->client_port == 25 ||
data->client_port == 587)
)
return true;
/* Match the server banner code */
if (match_smtp_banner(data->payload[0], data->payload_len[0])) {
if (match_smtp_command(data->payload[1], data->payload_len[1]))
return true;
}
if (match_smtp_banner(data->payload[1], data->payload_len[1])) {
if (match_smtp_command(data->payload[0], data->payload_len[0]))
return true;
}
return false;
}
static lpi_module_t lpi_smtp = {
LPI_PROTO_SMTP,
LPI_CATEGORY_MAIL,
"SMTP",
2,
match_smtp
};
void register_smtp(LPIModuleMap *mod_map) {
register_protocol(&lpi_smtp, mod_map);
}