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/* Copyright (C) 2007-2013 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.
*/
/**
* \ingroup decode
*
* @{
*/
/**
* \file
*
* \author Breno Silva Pinto <breno.silva@gmail.com>
*
* Decode PPP
*/
#include "suricata-common.h"
#include "decode.h"
#include "decode-ppp.h"
#include "decode-events.h"
#include "flow.h"
#include "util-unittest.h"
#include "util-debug.h"
int DecodePPP(ThreadVars *tv, DecodeThreadVars *dtv, Packet *p, uint8_t *pkt, uint16_t len, PacketQueue *pq)
{
StatsIncr(tv, dtv->counter_ppp);
if (unlikely(len < PPP_HEADER_LEN)) {
ENGINE_SET_INVALID_EVENT(p, PPP_PKT_TOO_SMALL);
return TM_ECODE_FAILED;
}
p->ppph = (PPPHdr *)pkt;
if (unlikely(p->ppph == NULL))
return TM_ECODE_FAILED;
SCLogDebug("p %p pkt %p PPP protocol %04x Len: %" PRId32 "",
p, pkt, ntohs(p->ppph->protocol), len);
switch (ntohs(p->ppph->protocol))
{
case PPP_VJ_UCOMP:
if (unlikely(len < (PPP_HEADER_LEN + IPV4_HEADER_LEN))) {
ENGINE_SET_INVALID_EVENT(p,PPPVJU_PKT_TOO_SMALL);
p->ppph = NULL;
return TM_ECODE_FAILED;
}
if (likely(IPV4_GET_RAW_VER((IPV4Hdr *)(pkt + PPP_HEADER_LEN)) == 4)) {
return DecodeIPV4(tv, dtv, p, pkt + PPP_HEADER_LEN, len - PPP_HEADER_LEN, pq);
} else
return TM_ECODE_FAILED;
break;
case PPP_IP:
if (unlikely(len < (PPP_HEADER_LEN + IPV4_HEADER_LEN))) {
ENGINE_SET_INVALID_EVENT(p,PPPIPV4_PKT_TOO_SMALL);
p->ppph = NULL;
return TM_ECODE_FAILED;
}
return DecodeIPV4(tv, dtv, p, pkt + PPP_HEADER_LEN, len - PPP_HEADER_LEN, pq);
/* PPP IPv6 was not tested */
case PPP_IPV6:
if (unlikely(len < (PPP_HEADER_LEN + IPV6_HEADER_LEN))) {
ENGINE_SET_INVALID_EVENT(p,PPPIPV6_PKT_TOO_SMALL);
p->ppph = NULL;
return TM_ECODE_FAILED;
}
return DecodeIPV6(tv, dtv, p, pkt + PPP_HEADER_LEN, len - PPP_HEADER_LEN, pq);
case PPP_VJ_COMP:
case PPP_IPX:
case PPP_OSI:
case PPP_NS:
case PPP_DECNET:
case PPP_APPLE:
case PPP_BRPDU:
case PPP_STII:
case PPP_VINES:
case PPP_HELLO:
case PPP_LUXCOM:
case PPP_SNS:
case PPP_MPLS_UCAST:
case PPP_MPLS_MCAST:
case PPP_IPCP:
case PPP_OSICP:
case PPP_NSCP:
case PPP_DECNETCP:
case PPP_APPLECP:
case PPP_IPXCP:
case PPP_STIICP:
case PPP_VINESCP:
case PPP_IPV6CP:
case PPP_MPLSCP:
case PPP_LCP:
case PPP_PAP:
case PPP_LQM:
case PPP_CHAP:
ENGINE_SET_EVENT(p,PPP_UNSUP_PROTO);
return TM_ECODE_OK;
default:
SCLogDebug("unknown PPP protocol: %" PRIx32 "",ntohs(p->ppph->protocol));
ENGINE_SET_INVALID_EVENT(p, PPP_WRONG_TYPE);
return TM_ECODE_OK;
}
}
/* TESTS BELOW */
#ifdef UNITTESTS
/* DecodePPPtest01
* Decode malformed ip layer PPP packet
* Expected test value: 1
*/
static int DecodePPPtest01 (void)
{
uint8_t raw_ppp[] = { 0xff, 0x03, 0x00, 0x21, 0x45, 0xc0, 0x00 };
Packet *p = PacketGetFromAlloc();
if (unlikely(p == NULL))
return 0;
ThreadVars tv;
DecodeThreadVars dtv;
memset(&tv, 0, sizeof(ThreadVars));
memset(&dtv, 0, sizeof(DecodeThreadVars));
DecodePPP(&tv, &dtv, p, raw_ppp, sizeof(raw_ppp), NULL);
/* Function my returns here with expected value */
if(ENGINE_ISSET_EVENT(p,PPPIPV4_PKT_TOO_SMALL)) {
SCFree(p);
return 1;
}
SCFree(p);
return 0;
}
/* DecodePPPtest02
* Decode malformed ppp layer packet
* Expected test value: 1
*/
static int DecodePPPtest02 (void)
{
uint8_t raw_ppp[] = { 0xff, 0x03, 0x00, 0xff, 0x45, 0xc0, 0x00, 0x2c, 0x4d,
0xed, 0x00, 0x00, 0xff, 0x06, 0xd5, 0x17, 0xbf, 0x01,
0x0d, 0x01, 0xbf, 0x01, 0x0d, 0x03, 0xea, 0x37, 0x00,
0x17, 0x6d, 0x0b, 0xba, 0xc3, 0x00, 0x00, 0x00, 0x00,
0x60, 0x02, 0x10, 0x20, 0xdd, 0xe1, 0x00, 0x00 };
Packet *p = PacketGetFromAlloc();
if (unlikely(p == NULL))
return 0;
ThreadVars tv;
DecodeThreadVars dtv;
memset(&tv, 0, sizeof(ThreadVars));
memset(&dtv, 0, sizeof(DecodeThreadVars));
DecodePPP(&tv, &dtv, p, raw_ppp, sizeof(raw_ppp), NULL);
/* Function must returns here */
if(ENGINE_ISSET_EVENT(p,PPP_WRONG_TYPE)) {
SCFree(p);
return 1;
}
SCFree(p);
return 0;
}
/** DecodePPPtest03
* \brief Decode good PPP packet, additionally the IPv4 packet inside is
* 4 bytes short.
* \retval 0 Test failed
* \retval 1 Test succeeded
*/
static int DecodePPPtest03 (void)
{
uint8_t raw_ppp[] = { 0xff, 0x03, 0x00, 0x21, 0x45, 0xc0, 0x00, 0x2c, 0x4d,
0xed, 0x00, 0x00, 0xff, 0x06, 0xd5, 0x17, 0xbf, 0x01,
0x0d, 0x01, 0xbf, 0x01, 0x0d, 0x03, 0xea, 0x37, 0x00,
0x17, 0x6d, 0x0b, 0xba, 0xc3, 0x00, 0x00, 0x00, 0x00,
0x60, 0x02, 0x10, 0x20, 0xdd, 0xe1, 0x00, 0x00 };
Packet *p = PacketGetFromAlloc();
if (unlikely(p == NULL))
return 0;
ThreadVars tv;
DecodeThreadVars dtv;
memset(&tv, 0, sizeof(ThreadVars));
memset(&dtv, 0, sizeof(DecodeThreadVars));
FlowInitConfig(FLOW_QUIET);
DecodePPP(&tv, &dtv, p, raw_ppp, sizeof(raw_ppp), NULL);
FlowShutdown();
if(p->ppph == NULL) {
SCFree(p);
return 0;
}
if(ENGINE_ISSET_EVENT(p,PPP_PKT_TOO_SMALL)) {
SCFree(p);
return 0;
}
if(ENGINE_ISSET_EVENT(p,PPPIPV4_PKT_TOO_SMALL)) {
SCFree(p);
return 0;
}
if(ENGINE_ISSET_EVENT(p,PPP_WRONG_TYPE)) {
SCFree(p);
return 0;
}
if (!(ENGINE_ISSET_EVENT(p,IPV4_TRUNC_PKT))) {
SCFree(p);
return 0;
}
/* Function must return here */
SCFree(p);
return 1;
}
/* DecodePPPtest04
* Check if ppp header is null
* Expected test value: 1
*/
static int DecodePPPtest04 (void)
{
uint8_t raw_ppp[] = { 0xff, 0x03, 0x00, 0x21, 0x45, 0xc0, 0x00, 0x2c, 0x4d,
0xed, 0x00, 0x00, 0xff, 0x06, 0xd5, 0x17, 0xbf, 0x01,
0x0d, 0x01, 0xbf, 0x01, 0x0d, 0x03, 0xea, 0x37, 0x00,
0x17, 0x6d, 0x0b, 0xba, 0xc3, 0x00, 0x00, 0x00, 0x00,
0x60, 0x02, 0x10, 0x20, 0xdd, 0xe1, 0x00, 0x00 };
Packet *p = PacketGetFromAlloc();
if (unlikely(p == NULL))
return 0;
ThreadVars tv;
DecodeThreadVars dtv;
memset(&tv, 0, sizeof(ThreadVars));
memset(&dtv, 0, sizeof(DecodeThreadVars));
FlowInitConfig(FLOW_QUIET);
DecodePPP(&tv, &dtv, p, raw_ppp, sizeof(raw_ppp), NULL);
FlowShutdown();
if(p->ppph == NULL) {
SCFree(p);
return 0;
}
if (!(ENGINE_ISSET_EVENT(p,IPV4_TRUNC_PKT))) {
SCFree(p);
return 0;
}
/* Function must returns here */
SCFree(p);
return 1;
}
#endif /* UNITTESTS */
void DecodePPPRegisterTests(void)
{
#ifdef UNITTESTS
UtRegisterTest("DecodePPPtest01", DecodePPPtest01, 1);
UtRegisterTest("DecodePPPtest02", DecodePPPtest02, 1);
UtRegisterTest("DecodePPPtest03", DecodePPPtest03, 1);
UtRegisterTest("DecodePPPtest04", DecodePPPtest04, 1);
#endif /* UNITTESTS */
}
/**
* @}
*/
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