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/*
* Copyright (c) 2008-2024 OARC, Inc.
* Copyright (c) 2007-2008, Internet Systems Consortium, Inc.
* Copyright (c) 2003-2007, The Measurement Factory, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "query_classification_index.h"
#include "config_hooks.h"
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
enum {
CLASS_OK,
CLASS_NONAUTH_TLD,
CLASS_ROOT_SERVERS_NET,
CLASS_LOCALHOST,
CLASS_A_FOR_A,
CLASS_A_FOR_ROOT,
CLASS_RFC1918_PTR,
CLASS_FUNNY_QCLASS,
CLASS_FUNNY_QTYPE,
CLASS_SRC_PORT_ZERO,
CLASS_MALFORMED
};
static int
nonauth_tld(const dns_message* m)
{
unsigned int i;
const char* tld = dns_message_tld((dns_message*)m);
for (i = 0; KnownTLDS[i]; i++)
if (0 == strcmp(KnownTLDS[i], tld))
return 0;
return CLASS_NONAUTH_TLD;
}
static int
root_servers_net(const dns_message* m)
{
if (0 == strcmp(m->qname + strlen(m->qname) - 16, "root-servers.net"))
return CLASS_ROOT_SERVERS_NET;
return 0;
}
static int
localhost(const dns_message* m)
{
if (0 == strcmp(m->qname + strlen(m->qname) - 9, "localhost"))
return CLASS_LOCALHOST;
return 0;
}
static int
a_for_a(const dns_message* m)
{
struct in_addr a;
if (m->qtype != T_A)
return 0;
if (inet_aton(m->qname, &a))
return CLASS_A_FOR_A;
return 0;
}
static int
a_for_root(const dns_message* m)
{
if (m->qtype != T_A)
return 0;
if (0 == strcmp(m->qname, "."))
return CLASS_A_FOR_ROOT;
return 0;
}
static int
rfc1918_ptr(const dns_message* m)
{
char* tok = 0;
char* t;
char q[1024];
unsigned int i = 0;
if (m->qtype != T_PTR)
return 0;
q[sizeof(q) - 1] = 0;
strncpy(q, m->qname, sizeof(q));
if (q[sizeof(q) - 1] != 0) {
// String was truncated
return 0;
}
if (NULL == (t = strstr(q, ".in-addr.arpa")))
return 0;
*t = '\0';
for (t = strtok_r(q, ".", &tok); t; t = strtok_r(NULL, ".", &tok)) {
i >>= 8;
i |= ((atoi(t) & 0xff) << 24);
}
if ((i & 0xff000000) == 0x0a000000) /* 10.0.0.0/8 */
return CLASS_RFC1918_PTR;
if ((i & 0xfff00000) == 0xac100000) /* 172.16.0.0/12 */
return CLASS_RFC1918_PTR;
if ((i & 0xffff0000) == 0xc0a80000) /* 192.168.0.0/16 */
return CLASS_RFC1918_PTR;
return 0;
}
static int
funny_qclass(const dns_message* m)
{
switch (m->qclass) {
case C_IN:
case C_CHAOS:
case C_ANY:
case C_NONE:
case C_HS:
return 0;
default:
break;
}
return CLASS_FUNNY_QCLASS;
}
static int
funny_qtype(const dns_message* m)
{
switch (m->qtype) {
case T_A:
case T_NS:
case T_MD:
case T_MF:
case T_CNAME:
case T_SOA:
case T_MB:
case T_MG:
case T_MR:
case T_NULL:
case T_WKS:
case T_PTR:
case T_HINFO:
case T_MINFO:
case T_MX:
case T_TXT:
case T_RP:
case T_AFSDB:
case T_X25:
case T_ISDN:
case T_RT:
case T_NSAP:
case T_NSAP_PTR:
case T_SIG:
case T_KEY:
case T_PX:
case T_GPOS:
case T_AAAA:
case T_A6:
case T_LOC:
case T_NXT:
case T_EID:
case T_NIMLOC:
case T_SRV:
case T_ATMA:
case T_NAPTR:
case T_OPT:
case T_IXFR:
case T_AXFR:
case T_MAILB:
case T_MAILA:
case T_ANY:
return 0;
default:
break;
}
return CLASS_FUNNY_QTYPE;
}
static int
src_port_zero(const dns_message* m)
{
if (0 == m->tm->src_port)
return CLASS_SRC_PORT_ZERO;
return 0;
}
static int
malformed(const dns_message* m)
{
if (m->malformed)
return CLASS_MALFORMED;
return 0;
}
int query_classification_indexer(const dns_message* m)
{
int x;
if ((x = malformed(m)))
return x;
if ((x = src_port_zero(m)))
return x;
if ((x = funny_qclass(m)))
return x;
if ((x = funny_qtype(m)))
return x;
if ((x = a_for_a(m)))
return x;
if ((x = a_for_root(m)))
return x;
if ((x = localhost(m)))
return x;
if ((x = root_servers_net(m)))
return x;
if ((x = nonauth_tld(m)))
return x;
if ((x = rfc1918_ptr(m)))
return x;
return CLASS_OK;
}
int query_classification_iterator(const char** label)
{
static int next_iter = 0;
if (NULL == label) {
next_iter = 0;
return CLASS_MALFORMED + 1;
}
if (CLASS_OK == next_iter)
*label = "ok";
else if (CLASS_NONAUTH_TLD == next_iter)
*label = "non-auth-tld";
else if (CLASS_ROOT_SERVERS_NET == next_iter)
*label = "root-servers.net";
else if (CLASS_LOCALHOST == next_iter)
*label = "localhost";
else if (CLASS_A_FOR_ROOT == next_iter)
*label = "a-for-root";
else if (CLASS_A_FOR_A == next_iter)
*label = "a-for-a";
else if (CLASS_RFC1918_PTR == next_iter)
*label = "rfc1918-ptr";
else if (CLASS_FUNNY_QCLASS == next_iter)
*label = "funny-qclass";
else if (CLASS_FUNNY_QTYPE == next_iter)
*label = "funny-qtype";
else if (CLASS_SRC_PORT_ZERO == next_iter)
*label = "src-port-zero";
else if (CLASS_MALFORMED == next_iter)
*label = "malformed";
else
return -1;
return next_iter++;
}
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