diff options
Diffstat (limited to 'framework/src/suricata/src/decode-mpls.c')
-rw-r--r-- | framework/src/suricata/src/decode-mpls.c | 325 |
1 files changed, 325 insertions, 0 deletions
diff --git a/framework/src/suricata/src/decode-mpls.c b/framework/src/suricata/src/decode-mpls.c new file mode 100644 index 00000000..1569ebfb --- /dev/null +++ b/framework/src/suricata/src/decode-mpls.c @@ -0,0 +1,325 @@ +/* Copyright (C) 2014 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 + * + * \author Jason Ish <jason.ish@emulex.com> + * + * MPLS decoder. + */ + +#include "suricata-common.h" +#include "decode.h" +#include "util-unittest.h" + +#define MPLS_HEADER_LEN 4 +#define MPLS_PW_LEN 4 +#define MPLS_MAX_RESERVED_LABEL 15 + +#define MPLS_LABEL_IPV4 0 +#define MPLS_LABEL_ROUTER_ALERT 1 +#define MPLS_LABEL_IPV6 2 +#define MPLS_LABEL_NULL 3 + +#define MPLS_LABEL(shim) ntohl(shim) >> 12 +#define MPLS_BOTTOM(shim) ((ntohl(shim) >> 8) & 0x1) + +/* Inner protocol guessing values. */ +#define MPLS_PROTO_ETHERNET_PW 0 +#define MPLS_PROTO_IPV4 4 +#define MPLS_PROTO_IPV6 6 + +int DecodeMPLS(ThreadVars *tv, DecodeThreadVars *dtv, Packet *p, uint8_t *pkt, + uint16_t len, PacketQueue *pq) +{ + uint32_t shim; + int label; + int event = 0; + + StatsIncr(tv, dtv->counter_mpls); + + do { + if (len < MPLS_HEADER_LEN) { + ENGINE_SET_INVALID_EVENT(p, MPLS_HEADER_TOO_SMALL); + return TM_ECODE_FAILED; + } + shim = *(uint32_t *)pkt; + pkt += MPLS_HEADER_LEN; + len -= MPLS_HEADER_LEN; + } while (MPLS_BOTTOM(shim) == 0); + + label = MPLS_LABEL(shim); + if (label == MPLS_LABEL_IPV4) { + return DecodeIPV4(tv, dtv, p, pkt, len, pq); + } + else if (label == MPLS_LABEL_ROUTER_ALERT) { + /* Not valid at the bottom of the stack. */ + event = MPLS_BAD_LABEL_ROUTER_ALERT; + } + else if (label == MPLS_LABEL_IPV6) { + return DecodeIPV6(tv, dtv, p, pkt, len, pq); + } + else if (label == MPLS_LABEL_NULL) { + /* Shouldn't appear on the wire. */ + event = MPLS_BAD_LABEL_IMPLICIT_NULL; + } + else if (label < MPLS_MAX_RESERVED_LABEL) { + event = MPLS_BAD_LABEL_RESERVED; + } + + if (event) { + goto end; + } + + /* Best guess at inner packet. */ + switch (pkt[0] >> 4) { + case MPLS_PROTO_IPV4: + DecodeIPV4(tv, dtv, p, pkt, len, pq); + break; + case MPLS_PROTO_IPV6: + DecodeIPV6(tv, dtv, p, pkt, len, pq); + break; + case MPLS_PROTO_ETHERNET_PW: + DecodeEthernet(tv, dtv, p, pkt + MPLS_PW_LEN, len - MPLS_PW_LEN, + pq); + break; + default: + ENGINE_SET_INVALID_EVENT(p, MPLS_UNKNOWN_PAYLOAD_TYPE); + return TM_ECODE_OK; + } + +end: + if (event) { + ENGINE_SET_EVENT(p, event); + } + return TM_ECODE_OK; +} + +#ifdef UNITTESTS + +static int DecodeMPLSTestHeaderTooSmall(void) +{ + int ret = 1; + + /* A packet that is too small to have a complete MPLS header. */ + uint8_t pkt[] = { + 0x00, 0x00, 0x11 + }; + + Packet *p = SCMalloc(SIZE_OF_PACKET); + if (unlikely(p == NULL)) { + return 0; + } + ThreadVars tv; + DecodeThreadVars dtv; + + memset(&dtv, 0, sizeof(DecodeThreadVars)); + memset(&tv, 0, sizeof(ThreadVars)); + memset(p, 0, SIZE_OF_PACKET); + + DecodeMPLS(&tv, &dtv, p, pkt, sizeof(pkt), NULL); + + if (!ENGINE_ISSET_EVENT(p, MPLS_HEADER_TOO_SMALL)) { + ret = 0; + } + + SCFree(p); + return ret; +} + +static int DecodeMPLSTestBadLabelRouterAlert(void) +{ + int ret = 1; + uint8_t pkt[] = { + 0x00, 0x00, 0x11, 0xff, 0x45, 0x00, 0x00, 0x64, + 0x00, 0x0a, 0x00, 0x00, 0xff, 0x01, 0xa5, 0x6a, + 0x0a, 0x01, 0x02, 0x01, 0x0a, 0x22, 0x00, 0x01, + 0x08, 0x00, 0x3a, 0x77, 0x0a, 0x39, 0x06, 0x2b, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x1f, 0x33, 0x50, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd + }; + + Packet *p = SCMalloc(SIZE_OF_PACKET); + if (unlikely(p == NULL)) { + return 0; + } + ThreadVars tv; + DecodeThreadVars dtv; + + memset(&dtv, 0, sizeof(DecodeThreadVars)); + memset(&tv, 0, sizeof(ThreadVars)); + memset(p, 0, SIZE_OF_PACKET); + + DecodeMPLS(&tv, &dtv, p, pkt, sizeof(pkt), NULL); + + if (!ENGINE_ISSET_EVENT(p, MPLS_BAD_LABEL_ROUTER_ALERT)) { + ret = 0; + } + + SCFree(p); + return ret; +} + +static int DecodeMPLSTestBadLabelImplicitNull(void) +{ + int ret = 1; + uint8_t pkt[] = { + 0x00, 0x00, 0x31, 0xff, 0x45, 0x00, 0x00, 0x64, + 0x00, 0x0a, 0x00, 0x00, 0xff, 0x01, 0xa5, 0x6a, + 0x0a, 0x01, 0x02, 0x01, 0x0a, 0x22, 0x00, 0x01, + 0x08, 0x00, 0x3a, 0x77, 0x0a, 0x39, 0x06, 0x2b, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x1f, 0x33, 0x50, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd + }; + + Packet *p = SCMalloc(SIZE_OF_PACKET); + if (unlikely(p == NULL)) { + return 0; + } + ThreadVars tv; + DecodeThreadVars dtv; + + memset(&dtv, 0, sizeof(DecodeThreadVars)); + memset(&tv, 0, sizeof(ThreadVars)); + memset(p, 0, SIZE_OF_PACKET); + + DecodeMPLS(&tv, &dtv, p, pkt, sizeof(pkt), NULL); + + if (!ENGINE_ISSET_EVENT(p, MPLS_BAD_LABEL_IMPLICIT_NULL)) { + ret = 0; + } + + SCFree(p); + return ret; +} + +static int DecodeMPLSTestBadLabelReserved(void) +{ + int ret = 1; + uint8_t pkt[] = { + 0x00, 0x00, 0x51, 0xff, 0x45, 0x00, 0x00, 0x64, + 0x00, 0x0a, 0x00, 0x00, 0xff, 0x01, 0xa5, 0x6a, + 0x0a, 0x01, 0x02, 0x01, 0x0a, 0x22, 0x00, 0x01, + 0x08, 0x00, 0x3a, 0x77, 0x0a, 0x39, 0x06, 0x2b, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x1f, 0x33, 0x50, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd + }; + + Packet *p = SCMalloc(SIZE_OF_PACKET); + if (unlikely(p == NULL)) { + return 0; + } + ThreadVars tv; + DecodeThreadVars dtv; + + memset(&dtv, 0, sizeof(DecodeThreadVars)); + memset(&tv, 0, sizeof(ThreadVars)); + memset(p, 0, SIZE_OF_PACKET); + + DecodeMPLS(&tv, &dtv, p, pkt, sizeof(pkt), NULL); + + if (!ENGINE_ISSET_EVENT(p, MPLS_BAD_LABEL_RESERVED)) { + ret = 0; + } + + SCFree(p); + return ret; +} + +static int DecodeMPLSTestUnknownPayloadType(void) +{ + int ret = 1; + + /* Valid label: 21. + * Unknown payload type: 1. + */ + uint8_t pkt[] = { + 0x00, 0x01, 0x51, 0xff, 0x15, 0x00, 0x00, 0x64, + 0x00, 0x0a, 0x00, 0x00, 0xff, 0x01, 0xa5, 0x6a, + 0x0a, 0x01, 0x02, 0x01, 0x0a, 0x22, 0x00, 0x01, + 0x08, 0x00, 0x3a, 0x77, 0x0a, 0x39, 0x06, 0x2b, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x1f, 0x33, 0x50, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, + 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd + }; + + Packet *p = SCMalloc(SIZE_OF_PACKET); + if (unlikely(p == NULL)) { + return 0; + } + ThreadVars tv; + DecodeThreadVars dtv; + + memset(&dtv, 0, sizeof(DecodeThreadVars)); + memset(&tv, 0, sizeof(ThreadVars)); + memset(p, 0, SIZE_OF_PACKET); + + DecodeMPLS(&tv, &dtv, p, pkt, sizeof(pkt), NULL); + + if (!ENGINE_ISSET_EVENT(p, MPLS_UNKNOWN_PAYLOAD_TYPE)) { + ret = 0; + } + + SCFree(p); + return ret; +} + +#endif /* UNITTESTS */ + +void DecodeMPLSRegisterTests(void) +{ +#ifdef UNITTESTS + UtRegisterTest("DecodeMPLSTestHeaderTooSmall", + DecodeMPLSTestHeaderTooSmall, 1); + UtRegisterTest("DecodeMPLSTestBadLabelRouterAlert", + DecodeMPLSTestBadLabelRouterAlert, 1); + UtRegisterTest("DecodeMPLSTestBadLabelImplicitNull", + DecodeMPLSTestBadLabelImplicitNull, 1); + UtRegisterTest("DecodeMPLSTestBadLabelReserved", + DecodeMPLSTestBadLabelReserved, 1); + UtRegisterTest("DecodeMPLSTestUnknownPayloadType", + DecodeMPLSTestUnknownPayloadType, 1); +#endif /* UNITTESTS */ +} |