dns: add keywords for additionals and authorities rrnames

Add keywords dns.additionals.rrname and dns.authorities.rrname. Along
the way, consolidate dns.query.name and dns.answer.name into a single file
and register them altogether since there is a lot of common code.
pull/12717/head
Jason Ish 10 months ago committed by Victor Julien
parent c57e1425f5
commit 814e9ffb7a

@ -7,22 +7,6 @@ matching on specific fields in DNS messages.
Note that sticky buffers are expected to be followed by one or more Note that sticky buffers are expected to be followed by one or more
:doc:`payload-keywords`. :doc:`payload-keywords`.
dns.answer.name
---------------
``dns.answer.name`` is a sticky buffer that is used to look at the
name field in DNS answer resource records.
``dns.answer.name`` will look at both requests and responses, so
``flow`` is recommended to confine to a specific direction.
The buffer being matched on contains the complete re-assembled
resource name, for example "www.suricata.io".
``dns.answer.name`` supports :doc:`multi-buffer-matching`.
``dns.answer.name`` was introduced in Suricata 8.0.0.
dns.opcode dns.opcode
---------- ----------
@ -134,9 +118,9 @@ pkt_data is used or it reaches the end of the rule.
.. note:: **dns.query** will only match on DNS request messages, to .. note:: **dns.query** will only match on DNS request messages, to
also match on DNS response message, see also match on DNS response message, see
`dns.query.name`_. `dns.queries.rrname`_.
``dns.query.name`` supports :doc:`multi-buffer-matching`. ``dns.queries.rrname`` supports :doc:`multi-buffer-matching`.
Normalized Buffer Normalized Buffer
~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~
@ -160,22 +144,71 @@ DNS query on the wire (snippet)::
mail.google.com mail.google.com
dns.query.name dns.queries.rrname
--------------- ------------------
``dns.queries.rrname`` is a sticky buffer that is used to look at the
name field in DNS query (question) resource records. It is nearly
identical to ``dns.query`` but supports both DNS requests and
responses.
``dns.queries.rrname`` will look at both requests and responses, so
``flow`` is recommended to confine to a specific direction.
The buffer being matched on contains the complete re-assembled
resource name, for example "www.suricata.io".
``dns.queries.rrname`` supports :doc:`multi-buffer-matching`.
``dns.queries.rrname`` was introduced in Suricata 8.0.0.
``dns.query.name`` is a sticky buffer that is used to look at the name dns.answers.rrname
field in DNS query (question) resource records. It is nearly identical ------------------
to ``dns.query`` but supports both DNS requests and responses.
``dns.query.name`` will look at both requests and responses, so ``dns.answers.rrname`` is a sticky buffer that is used to look at the
name field in DNS answer resource records.
``dns.answers.rrname`` will look at both requests and responses, so
``flow`` is recommended to confine to a specific direction. ``flow`` is recommended to confine to a specific direction.
The buffer being matched on contains the complete re-assembled The buffer being matched on contains the complete re-assembled
resource name, for example "www.suricata.io". resource name, for example "www.suricata.io".
``dns.query.name`` supports :doc:`multi-buffer-matching`. ``dns.answers.rrname`` supports :doc:`multi-buffer-matching`.
``dns.answers.rrname`` was introduced in Suricata 8.0.0.
dns.authorities.rrname
----------------------
``dns.authorities.rrname`` is a sticky buffer that is used to look at the
rrname field in DNS authority resource records.
``dns.authorities.rrname`` will look at both requests and responses,
so ``flow`` is recommended to confine to a specific direction.
The buffer being matched on contains the complete re-assembled
resource name, for example "www.suricata.io".
``dns.authorities.rrname`` supports :doc:`multi-buffer-matching`.
``dns.authorities.rrname`` was introduced in Suricata 8.0.0.
dns.additionals.rrname
----------------------
``dns.additionals.rrname`` is a sticky buffer that is used to look at
the rrname field in DNS additional resource records.
``dns.additionals.rrname`` will look at both requests and responses,
so ``flow`` is recommended to confine to a specific direction.
The buffer being matched on contains the complete re-assembled
resource name, for example "www.suricata.io".
``dns.additionals.rrname`` supports :doc:`multi-buffer-matching`.
``dns.query.name`` was introduced in Suricata 8.0.0. ``dns.additionals.rrname`` was introduced in Suricata 8.0.0.
dns.response.rrname dns.response.rrname
------------------- -------------------

@ -112,13 +112,12 @@ noinst_HEADERS = \
detect-detection-filter.h \ detect-detection-filter.h \
detect-distance.h \ detect-distance.h \
detect-dnp3.h \ detect-dnp3.h \
detect-dns-answer-name.h \ detect-dns-name.h \
detect-dns-opcode.h \ detect-dns-opcode.h \
detect-dns-rcode.h \ detect-dns-rcode.h \
detect-dns-response.h \ detect-dns-response.h \
detect-dns-rrtype.h \ detect-dns-rrtype.h \
detect-dns-query.h \ detect-dns-query.h \
detect-dns-query-name.h \
detect-dsize.h \ detect-dsize.h \
detect-engine-address.h \ detect-engine-address.h \
detect-engine-address-ipv4.h \ detect-engine-address-ipv4.h \
@ -689,13 +688,12 @@ libsuricata_c_a_SOURCES = \
detect-detection-filter.c \ detect-detection-filter.c \
detect-distance.c \ detect-distance.c \
detect-dnp3.c \ detect-dnp3.c \
detect-dns-answer-name.c \ detect-dns-name.c \
detect-dns-opcode.c \ detect-dns-opcode.c \
detect-dns-rcode.c \ detect-dns-rcode.c \
detect-dns-response.c \ detect-dns-response.c \
detect-dns-rrtype.c \ detect-dns-rrtype.c \
detect-dns-query.c \ detect-dns-query.c \
detect-dns-query-name.c \
detect-dsize.c \ detect-dsize.c \
detect-engine-address.c \ detect-engine-address.c \
detect-engine-address-ipv4.c \ detect-engine-address-ipv4.c \

@ -1,92 +0,0 @@
/* Copyright (C) 2023 Open Information Security Foundation
*
* You can copy, redistribute or modify this Program under the terms of
* the GNU General Public License version 2 as published by the Free
* Software Foundation.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* version 2 along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/
/**
* \file
*
* Detect keyword for DNS answer name: dns.answer.name
*/
#include "detect.h"
#include "detect-parse.h"
#include "detect-engine.h"
#include "detect-engine-prefilter.h"
#include "detect-engine-content-inspection.h"
#include "detect-dns-answer-name.h"
#include "util-profiling.h"
#include "rust.h"
static int detect_buffer_id = 0;
static int DetectSetup(DetectEngineCtx *de_ctx, Signature *s, const char *str)
{
if (DetectBufferSetActiveList(de_ctx, s, detect_buffer_id) < 0) {
return -1;
}
if (DetectSignatureSetAppProto(s, ALPROTO_DNS) < 0) {
return -1;
}
return 0;
}
static InspectionBuffer *GetBuffer(DetectEngineThreadCtx *det_ctx,
const DetectEngineTransforms *transforms, Flow *f, uint8_t flags, void *txv, int list_id,
uint32_t index)
{
InspectionBuffer *buffer = InspectionBufferMultipleForListGet(det_ctx, list_id, index);
if (buffer == NULL) {
return NULL;
}
if (buffer->initialized) {
return buffer;
}
bool to_client = (flags & STREAM_TOSERVER) == 0;
const uint8_t *data = NULL;
uint32_t data_len = 0;
if (!SCDnsTxGetAnswerName(txv, to_client, index, &data, &data_len)) {
InspectionBufferSetupMultiEmpty(buffer);
return NULL;
}
InspectionBufferSetupMulti(buffer, transforms, data, data_len);
buffer->flags = DETECT_CI_FLAGS_SINGLE;
return buffer;
}
void DetectDnsAnswerNameRegister(void)
{
static const char *keyword = "dns.answer.name";
sigmatch_table[DETECT_DNS_ANSWER_NAME].name = keyword;
sigmatch_table[DETECT_DNS_ANSWER_NAME].desc = "DNS answer name sticky buffer";
sigmatch_table[DETECT_DNS_ANSWER_NAME].url = "/rules/dns-keywords.html#dns-answer-name";
sigmatch_table[DETECT_DNS_ANSWER_NAME].Setup = DetectSetup;
sigmatch_table[DETECT_DNS_ANSWER_NAME].flags |= SIGMATCH_NOOPT;
sigmatch_table[DETECT_DNS_ANSWER_NAME].flags |= SIGMATCH_INFO_STICKY_BUFFER;
/* Register in the TO_SERVER direction, even though this is not
normal, it could be provided as part of a request. */
DetectAppLayerMultiRegister(keyword, ALPROTO_DNS, SIG_FLAG_TOSERVER, 0, GetBuffer, 2, 1);
/* Register in the TO_CLIENT direction. */
DetectAppLayerMultiRegister(keyword, ALPROTO_DNS, SIG_FLAG_TOCLIENT, 0, GetBuffer, 2, 1);
DetectBufferTypeSetDescriptionByName(keyword, "dns answer name");
DetectBufferTypeSupportsMultiInstance(keyword);
detect_buffer_id = DetectBufferTypeGetByName(keyword);
}

@ -1,23 +0,0 @@
/* Copyright (C) 2023 Open Information Security Foundation
*
* You can copy, redistribute or modify this Program under the terms of
* the GNU General Public License version 2 as published by the Free
* Software Foundation.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* version 2 along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/
#ifndef SURICATA_DETECT_DNS_ANSWER_NAME_H
#define SURICATA_DETECT_DNS_ANSWER_NAME_H
void DetectDnsAnswerNameRegister(void);
#endif /* SURICATA_DETECT_DNS_ANSWER_NAME_H */

@ -0,0 +1,188 @@
/* Copyright (C) 2025 Open Information Security Foundation
*
* You can copy, redistribute or modify this Program under the terms of
* the GNU General Public License version 2 as published by the Free
* Software Foundation.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* version 2 along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/
/**
* \file
*
* Detect keyword for DNS rrnames:
* - dns.queries.rrname
* - dns.answers.rrname
* - dns.authorities.name
* - dns.additionals.name
*/
#include "detect.h"
#include "detect-parse.h"
#include "detect-engine.h"
#include "detect-engine-content-inspection.h"
#include "detect-engine-helper.h"
#include "detect-dns-name.h"
#include "rust.h"
enum DnsSection {
DNS_QUERY = 0,
DNS_ANSWER,
DNS_AUTHORITY,
DNS_ADDITIONAL,
};
static int query_buffer_id = 0;
static int answer_buffer_id = 0;
static int authority_buffer_id = 0;
static int additional_buffer_id = 0;
static int DetectSetup(DetectEngineCtx *de_ctx, Signature *s, const char *str, int id)
{
if (DetectBufferSetActiveList(de_ctx, s, id) < 0) {
return -1;
}
if (DetectSignatureSetAppProto(s, ALPROTO_DNS) < 0) {
return -1;
}
return 0;
}
static int SetupQueryBuffer(DetectEngineCtx *de_ctx, Signature *s, const char *str)
{
return DetectSetup(de_ctx, s, str, query_buffer_id);
}
static int SetupAnswerBuffer(DetectEngineCtx *de_ctx, Signature *s, const char *str)
{
return DetectSetup(de_ctx, s, str, answer_buffer_id);
}
static int SetupAdditionalsBuffer(DetectEngineCtx *de_ctx, Signature *s, const char *str)
{
return DetectSetup(de_ctx, s, str, additional_buffer_id);
}
static int SetupAuthoritiesBuffer(DetectEngineCtx *de_ctx, Signature *s, const char *str)
{
return DetectSetup(de_ctx, s, str, authority_buffer_id);
}
static InspectionBuffer *GetBuffer(DetectEngineThreadCtx *det_ctx,
const DetectEngineTransforms *transforms, Flow *f, uint8_t flags, void *txv, int list_id,
uint32_t index, enum DnsSection what)
{
InspectionBuffer *buffer = InspectionBufferMultipleForListGet(det_ctx, list_id, index);
if (buffer == NULL) {
return NULL;
}
if (buffer->initialized) {
return buffer;
}
bool to_client = (flags & STREAM_TOSERVER) == 0;
const uint8_t *data = NULL;
uint32_t data_len = 0;
bool ok = false;
switch (what) {
case DNS_QUERY:
ok = SCDnsTxGetQueryName(txv, to_client, index, &data, &data_len);
break;
case DNS_ANSWER:
ok = SCDnsTxGetAnswerName(txv, to_client, index, &data, &data_len);
break;
case DNS_AUTHORITY:
ok = SCDnsTxGetAuthorityName(txv, index, &data, &data_len);
break;
case DNS_ADDITIONAL:
ok = SCDnsTxGetAdditionalName(txv, index, &data, &data_len);
break;
default:
DEBUG_VALIDATE_BUG_ON("unhandled dns rrname type");
InspectionBufferSetupMultiEmpty(buffer);
return NULL;
}
if (ok) {
InspectionBufferSetupMulti(buffer, transforms, data, data_len);
buffer->flags = DETECT_CI_FLAGS_SINGLE;
return buffer;
}
InspectionBufferSetupMultiEmpty(buffer);
return NULL;
}
static InspectionBuffer *GetQueryBuffer(DetectEngineThreadCtx *det_ctx,
const DetectEngineTransforms *transforms, Flow *f, uint8_t flags, void *txv, int list_id,
uint32_t index)
{
return GetBuffer(det_ctx, transforms, f, flags, txv, list_id, index, DNS_QUERY);
}
static InspectionBuffer *GetAnswerBuffer(DetectEngineThreadCtx *det_ctx,
const DetectEngineTransforms *transforms, Flow *f, uint8_t flags, void *txv, int list_id,
uint32_t index)
{
return GetBuffer(det_ctx, transforms, f, flags, txv, list_id, index, DNS_ANSWER);
}
static InspectionBuffer *GetAuthorityBuffer(DetectEngineThreadCtx *det_ctx,
const DetectEngineTransforms *transforms, Flow *f, uint8_t flags, void *txv, int list_id,
uint32_t index)
{
return GetBuffer(det_ctx, transforms, f, flags, txv, list_id, index, DNS_AUTHORITY);
}
static InspectionBuffer *GetAdditionalBuffer(DetectEngineThreadCtx *det_ctx,
const DetectEngineTransforms *transforms, Flow *f, uint8_t flags, void *txv, int list_id,
uint32_t index)
{
return GetBuffer(det_ctx, transforms, f, flags, txv, list_id, index, DNS_ADDITIONAL);
}
static int Register(const char *keyword, const char *desc, const char *doc,
int (*Setup)(DetectEngineCtx *, Signature *, const char *),
InspectionMultiBufferGetDataPtr GetBufferFn)
{
int keyword_id = SCDetectHelperNewKeywordId();
sigmatch_table[keyword_id].name = keyword;
sigmatch_table[keyword_id].desc = desc;
sigmatch_table[keyword_id].url = doc;
sigmatch_table[keyword_id].Setup = Setup;
sigmatch_table[keyword_id].flags |= SIGMATCH_NOOPT;
sigmatch_table[keyword_id].flags |= SIGMATCH_INFO_STICKY_BUFFER;
DetectAppLayerMultiRegister(keyword, ALPROTO_DNS, SIG_FLAG_TOSERVER, 0, GetBufferFn, 2, 1);
DetectAppLayerMultiRegister(keyword, ALPROTO_DNS, SIG_FLAG_TOCLIENT, 0, GetBufferFn, 2, 1);
DetectBufferTypeSetDescriptionByName(keyword, keyword);
DetectBufferTypeSupportsMultiInstance(keyword);
return DetectBufferTypeGetByName(keyword);
}
void DetectDnsNameRegister(void)
{
query_buffer_id = Register("dns.queries.rrname", "DNS query rrname sticky buffer",
"/rules/dns-keywords.html#dns.queries.rrname", SetupQueryBuffer, GetQueryBuffer);
answer_buffer_id = Register("dns.answers.rrname", "DNS answer rrname sticky buffer",
"/rules/dns-keywords.html#dns.answers.rrname", SetupAnswerBuffer, GetAnswerBuffer);
additional_buffer_id =
Register("dns.additionals.rrname", "DNS additionals rrname sticky buffer",
"/rules/dns-keywords.html#dns-additionals-rrname", SetupAdditionalsBuffer,
GetAdditionalBuffer);
authority_buffer_id = Register("dns.authorities.rrname", "DNS authorities rrname sticky buffer",
"/rules/dns-keywords.html#dns-authorities-rrname", SetupAuthoritiesBuffer,
GetAuthorityBuffer);
}

@ -15,9 +15,9 @@
* 02110-1301, USA. * 02110-1301, USA.
*/ */
#ifndef SURICATA_DETECT_DNS_QUERY_NAME_H #ifndef SURICATA_DETECT_DNS_NAME_H
#define SURICATA_DETECT_DNS_QUERY_NAME_H #define SURICATA_DETECT_DNS_NAME_H
void DetectDnsQueryNameRegister(void); void DetectDnsNameRegister(void);
#endif /* SURICATA_DETECT_DNS_QUERY_NAME_H */ #endif /* SURICATA_DETECT_DNS_NAME_H */

@ -1,91 +0,0 @@
/* Copyright (C) 2023 Open Information Security Foundation
*
* You can copy, redistribute or modify this Program under the terms of
* the GNU General Public License version 2 as published by the Free
* Software Foundation.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* version 2 along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/
/**
* \file
*
* Detect keyword for DNS query names: dns.query.name
*/
#include "detect.h"
#include "detect-parse.h"
#include "detect-engine.h"
#include "detect-engine-prefilter.h"
#include "detect-engine-content-inspection.h"
#include "detect-dns-query-name.h"
#include "util-profiling.h"
#include "rust.h"
static int detect_buffer_id = 0;
static int DetectSetup(DetectEngineCtx *de_ctx, Signature *s, const char *str)
{
if (DetectBufferSetActiveList(de_ctx, s, detect_buffer_id) < 0) {
return -1;
}
if (DetectSignatureSetAppProto(s, ALPROTO_DNS) < 0) {
return -1;
}
return 0;
}
static InspectionBuffer *GetBuffer(DetectEngineThreadCtx *det_ctx,
const DetectEngineTransforms *transforms, Flow *f, const uint8_t flags, void *txv,
int list_id, uint32_t index)
{
InspectionBuffer *buffer = InspectionBufferMultipleForListGet(det_ctx, list_id, index);
if (buffer == NULL) {
return NULL;
}
if (buffer->initialized) {
return buffer;
}
bool to_client = (flags & STREAM_TOSERVER) == 0;
const uint8_t *data = NULL;
uint32_t data_len = 0;
if (!SCDnsTxGetQueryName(txv, to_client, index, &data, &data_len)) {
InspectionBufferSetupMultiEmpty(buffer);
return NULL;
}
InspectionBufferSetupMulti(buffer, transforms, data, data_len);
buffer->flags = DETECT_CI_FLAGS_SINGLE;
return buffer;
}
void DetectDnsQueryNameRegister(void)
{
static const char *keyword = "dns.query.name";
sigmatch_table[DETECT_DNS_QUERY_NAME].name = keyword;
sigmatch_table[DETECT_DNS_QUERY_NAME].desc = "DNS query name sticky buffer";
sigmatch_table[DETECT_DNS_QUERY_NAME].url = "/rules/dns-keywords.html#dns-query-name";
sigmatch_table[DETECT_DNS_QUERY_NAME].Setup = DetectSetup;
sigmatch_table[DETECT_DNS_QUERY_NAME].flags |= SIGMATCH_NOOPT;
sigmatch_table[DETECT_DNS_QUERY_NAME].flags |= SIGMATCH_INFO_STICKY_BUFFER;
/* Register in both directions as the query is usually echoed back
in the response. */
DetectAppLayerMultiRegister(keyword, ALPROTO_DNS, SIG_FLAG_TOSERVER, 0, GetBuffer, 2, 1);
DetectAppLayerMultiRegister(keyword, ALPROTO_DNS, SIG_FLAG_TOCLIENT, 0, GetBuffer, 2, 1);
DetectBufferTypeSetDescriptionByName(keyword, "dns query name");
DetectBufferTypeSupportsMultiInstance(keyword);
detect_buffer_id = DetectBufferTypeGetByName(keyword);
}

@ -51,8 +51,7 @@
#include "detect-dns-rcode.h" #include "detect-dns-rcode.h"
#include "detect-dns-rrtype.h" #include "detect-dns-rrtype.h"
#include "detect-dns-query.h" #include "detect-dns-query.h"
#include "detect-dns-answer-name.h" #include "detect-dns-name.h"
#include "detect-dns-query-name.h"
#include "detect-dns-response.h" #include "detect-dns-response.h"
#include "detect-tls-sni.h" #include "detect-tls-sni.h"
#include "detect-tls-certs.h" #include "detect-tls-certs.h"
@ -558,8 +557,7 @@ void SigTableSetup(void)
DetectDnsOpcodeRegister(); DetectDnsOpcodeRegister();
DetectDnsRcodeRegister(); DetectDnsRcodeRegister();
DetectDnsRrtypeRegister(); DetectDnsRrtypeRegister();
DetectDnsAnswerNameRegister(); DetectDnsNameRegister();
DetectDnsQueryNameRegister();
DetectDnsResponseRegister(); DetectDnsResponseRegister();
DetectModbusRegister(); DetectModbusRegister();
DetectDNP3Register(); DetectDNP3Register();

@ -248,8 +248,6 @@ enum DetectKeywordId {
DETECT_DNS_RCODE, DETECT_DNS_RCODE,
DETECT_DNS_RESPONSE, DETECT_DNS_RESPONSE,
DETECT_DNS_RRTYPE, DETECT_DNS_RRTYPE,
DETECT_DNS_ANSWER_NAME,
DETECT_DNS_QUERY_NAME,
DETECT_TLS_SNI, DETECT_TLS_SNI,
DETECT_TLS_CERTS, DETECT_TLS_CERTS,
DETECT_TLS_CERT_ISSUER, DETECT_TLS_CERT_ISSUER,

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