Adding upstream version 1:7.0.3.upstream/1%7.0.3

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 598 insertions, 0 deletions

diff --git a/src/decode-tcp.c b/src/decode-tcp.c
new file mode 100644
index 0000000..49bb882
--- /dev/null
+++ b/src/decode-tcp.c
@@ -0,0 +1,598 @@
+/* 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 Victor Julien <victor@inliniac.net>
+ *
+ * Decode TCP
+ */
+
+#include "suricata-common.h"
+#include "decode-tcp.h"
+#include "decode.h"
+#include "decode-events.h"
+#include "util-unittest.h"
+#include "util-debug.h"
+#include "util-optimize.h"
+#include "flow.h"
+
+#define SET_OPTS(dst, src) \
+    (dst).type = (src).type; \
+    (dst).len  = (src).len; \
+    (dst).data = (src).data
+
+static void DecodeTCPOptions(Packet *p, const uint8_t *pkt, uint16_t pktlen)
+{
+    uint8_t tcp_opt_cnt = 0;
+    TCPOpt tcp_opts[TCP_OPTMAX];
+
+    uint16_t plen = pktlen;
+    while (plen)
+    {
+        const uint8_t type = *pkt;
+
+        /* single byte options */
+        if (type == TCP_OPT_EOL) {
+            break;
+        } else if (type == TCP_OPT_NOP) {
+            pkt++;
+            plen--;
+
+        /* multibyte options */
+        } else {
+            if (plen < 2) {
+                break;
+            }
+
+            const uint8_t olen = *(pkt+1);
+
+            /* we already know that the total options len is valid,
+             * so here the len of the specific option must be bad.
+             * Also check for invalid lengths 0 and 1. */
+            if (unlikely(olen > plen || olen < 2)) {
+                ENGINE_SET_INVALID_EVENT(p, TCP_OPT_INVALID_LEN);
+                return;
+            }
+
+            tcp_opts[tcp_opt_cnt].type = type;
+            tcp_opts[tcp_opt_cnt].len  = olen;
+            tcp_opts[tcp_opt_cnt].data = (olen > 2) ? (pkt+2) : NULL;
+
+            /* we are parsing the most commonly used opts to prevent
+             * us from having to walk the opts list for these all the
+             * time. */
+            switch (type) {
+                case TCP_OPT_WS:
+                    if (olen != TCP_OPT_WS_LEN) {
+                        ENGINE_SET_EVENT(p,TCP_OPT_INVALID_LEN);
+                    } else {
+                        if (p->tcpvars.ws.type != 0) {
+                            ENGINE_SET_EVENT(p,TCP_OPT_DUPLICATE);
+                        } else {
+                            SET_OPTS(p->tcpvars.ws, tcp_opts[tcp_opt_cnt]);
+                        }
+                    }
+                    break;
+                case TCP_OPT_MSS:
+                    if (olen != TCP_OPT_MSS_LEN) {
+                        ENGINE_SET_EVENT(p,TCP_OPT_INVALID_LEN);
+                    } else {
+                        if (p->tcpvars.mss.type != 0) {
+                            ENGINE_SET_EVENT(p,TCP_OPT_DUPLICATE);
+                        } else {
+                            SET_OPTS(p->tcpvars.mss, tcp_opts[tcp_opt_cnt]);
+                        }
+                    }
+                    break;
+                case TCP_OPT_SACKOK:
+                    if (olen != TCP_OPT_SACKOK_LEN) {
+                        ENGINE_SET_EVENT(p,TCP_OPT_INVALID_LEN);
+                    } else {
+                        if (p->tcpvars.sackok.type != 0) {
+                            ENGINE_SET_EVENT(p,TCP_OPT_DUPLICATE);
+                        } else {
+                            SET_OPTS(p->tcpvars.sackok, tcp_opts[tcp_opt_cnt]);
+                        }
+                    }
+                    break;
+                case TCP_OPT_TS:
+                    if (olen != TCP_OPT_TS_LEN) {
+                        ENGINE_SET_EVENT(p,TCP_OPT_INVALID_LEN);
+                    } else {
+                        if (p->tcpvars.ts_set) {
+                            ENGINE_SET_EVENT(p,TCP_OPT_DUPLICATE);
+                        } else {
+                            uint32_t values[2];
+                            memcpy(&values, tcp_opts[tcp_opt_cnt].data, sizeof(values));
+                            p->tcpvars.ts_val = SCNtohl(values[0]);
+                            p->tcpvars.ts_ecr = SCNtohl(values[1]);
+                            p->tcpvars.ts_set = true;
+                        }
+                    }
+                    break;
+                case TCP_OPT_SACK:
+                    SCLogDebug("SACK option, len %u", olen);
+                    if ((olen != 2) &&
+                           (olen < TCP_OPT_SACK_MIN_LEN ||
+                            olen > TCP_OPT_SACK_MAX_LEN ||
+                            !((olen - 2) % 8 == 0)))
+                    {
+                        ENGINE_SET_EVENT(p,TCP_OPT_INVALID_LEN);
+                    } else {
+                        if (p->tcpvars.sack.type != 0) {
+                            ENGINE_SET_EVENT(p,TCP_OPT_DUPLICATE);
+                        } else {
+                            SET_OPTS(p->tcpvars.sack, tcp_opts[tcp_opt_cnt]);
+                        }
+                    }
+                    break;
+                case TCP_OPT_TFO:
+                    SCLogDebug("TFO option, len %u", olen);
+                    if ((olen != 2) && (olen < TCP_OPT_TFO_MIN_LEN || olen > TCP_OPT_TFO_MAX_LEN ||
+                                               !(((olen - 2) & 0x1) == 0))) {
+                        ENGINE_SET_EVENT(p,TCP_OPT_INVALID_LEN);
+                    } else {
+                        if (p->tcpvars.tfo.type != 0) {
+                            ENGINE_SET_EVENT(p,TCP_OPT_DUPLICATE);
+                        } else {
+                            SET_OPTS(p->tcpvars.tfo, tcp_opts[tcp_opt_cnt]);
+                        }
+                    }
+                    break;
+                /* experimental options, could be TFO */
+                case TCP_OPT_EXP1:
+                case TCP_OPT_EXP2:
+                    SCLogDebug("TCP EXP option, len %u", olen);
+                    if (olen == 4 || olen == 12) {
+                        uint16_t magic = SCNtohs(*(uint16_t *)tcp_opts[tcp_opt_cnt].data);
+                        if (magic == 0xf989) {
+                            if (p->tcpvars.tfo.type != 0) {
+                                ENGINE_SET_EVENT(p,TCP_OPT_DUPLICATE);
+                            } else {
+                                SET_OPTS(p->tcpvars.tfo, tcp_opts[tcp_opt_cnt]);
+                                p->tcpvars.tfo.type = TCP_OPT_TFO; // treat as regular TFO
+                            }
+                        }
+                    } else {
+                        ENGINE_SET_EVENT(p,TCP_OPT_INVALID_LEN);
+                    }
+                    break;
+                /* RFC 2385 MD5 option */
+                case TCP_OPT_MD5:
+                    SCLogDebug("MD5 option, len %u", olen);
+                    if (olen != 18) {
+                        ENGINE_SET_INVALID_EVENT(p,TCP_OPT_INVALID_LEN);
+                    } else {
+                        /* we can't validate the option as the key is out of band */
+                        p->tcpvars.md5_option_present = true;
+                    }
+                    break;
+                /* RFC 5925 AO option */
+                case TCP_OPT_AO:
+                    SCLogDebug("AU option, len %u", olen);
+                    if (olen < 4) {
+                        ENGINE_SET_INVALID_EVENT(p,TCP_OPT_INVALID_LEN);
+                    } else {
+                        /* we can't validate the option as the key is out of band */
+                        p->tcpvars.ao_option_present = true;
+                    }
+                    break;
+            }
+
+            pkt += olen;
+            plen -= olen;
+            tcp_opt_cnt++;
+        }
+    }
+}
+
+static int DecodeTCPPacket(ThreadVars *tv, Packet *p, const uint8_t *pkt, uint16_t len)
+{
+    if (unlikely(len < TCP_HEADER_LEN)) {
+        ENGINE_SET_INVALID_EVENT(p, TCP_PKT_TOO_SMALL);
+        return -1;
+    }
+
+    p->tcph = (TCPHdr *)pkt;
+
+    uint8_t hlen = TCP_GET_HLEN(p);
+    if (unlikely(len < hlen)) {
+        ENGINE_SET_INVALID_EVENT(p, TCP_HLEN_TOO_SMALL);
+        return -1;
+    }
+
+    uint8_t tcp_opt_len = hlen - TCP_HEADER_LEN;
+    if (unlikely(tcp_opt_len > TCP_OPTLENMAX)) {
+        ENGINE_SET_INVALID_EVENT(p, TCP_INVALID_OPTLEN);
+        return -1;
+    }
+
+    if (likely(tcp_opt_len > 0)) {
+        DecodeTCPOptions(p, pkt + TCP_HEADER_LEN, tcp_opt_len);
+    }
+
+    SET_TCP_SRC_PORT(p,&p->sp);
+    SET_TCP_DST_PORT(p,&p->dp);
+
+    p->proto = IPPROTO_TCP;
+
+    p->payload = (uint8_t *)pkt + hlen;
+    p->payload_len = len - hlen;
+
+    return 0;
+}
+
+int DecodeTCP(ThreadVars *tv, DecodeThreadVars *dtv, Packet *p,
+        const uint8_t *pkt, uint16_t len)
+{
+    StatsIncr(tv, dtv->counter_tcp);
+
+    if (unlikely(DecodeTCPPacket(tv, p, pkt,len) < 0)) {
+        SCLogDebug("invalid TCP packet");
+        CLEAR_TCP_PACKET(p);
+        return TM_ECODE_FAILED;
+    }
+
+    /* update counters */
+    if ((p->tcph->th_flags & (TH_SYN | TH_ACK)) == (TH_SYN | TH_ACK)) {
+        StatsIncr(tv, dtv->counter_tcp_synack);
+    } else if (p->tcph->th_flags & (TH_SYN)) {
+        StatsIncr(tv, dtv->counter_tcp_syn);
+    }
+    if (p->tcph->th_flags & (TH_RST)) {
+        StatsIncr(tv, dtv->counter_tcp_rst);
+    }
+#ifdef DEBUG
+    SCLogDebug("TCP sp: %" PRIu32 " -> dp: %" PRIu32 " - HLEN: %" PRIu32 " LEN: %" PRIu32 " %s%s%s%s%s%s",
+        GET_TCP_SRC_PORT(p), GET_TCP_DST_PORT(p), TCP_GET_HLEN(p), len,
+        TCP_HAS_SACKOK(p) ? "SACKOK " : "", TCP_HAS_SACK(p) ? "SACK " : "",
+        TCP_HAS_WSCALE(p) ? "WS " : "", TCP_HAS_TS(p) ? "TS " : "",
+        TCP_HAS_MSS(p) ? "MSS " : "", TCP_HAS_TFO(p) ? "TFO " : "");
+#endif
+
+    FlowSetupPacket(p);
+
+    return TM_ECODE_OK;
+}
+
+#ifdef UNITTESTS
+#include "util-unittest-helper.h"
+#include "packet.h"
+
+static int TCPCalculateValidChecksumtest01(void)
+{
+    uint16_t csum = 0;
+
+    uint8_t raw_ipshdr[] = {
+        0x40, 0x8e, 0x7e, 0xb2, 0xc0, 0xa8, 0x01, 0x03};
+
+    uint8_t raw_tcp[] = {
+        0x00, 0x50, 0x8e, 0x16, 0x0d, 0x59, 0xcd, 0x3c,
+        0xcf, 0x0d, 0x21, 0x80, 0xa0, 0x12, 0x16, 0xa0,
+        0xfa, 0x03, 0x00, 0x00, 0x02, 0x04, 0x05, 0xb4,
+        0x04, 0x02, 0x08, 0x0a, 0x6e, 0x18, 0x78, 0x73,
+        0x01, 0x71, 0x74, 0xde, 0x01, 0x03, 0x03, 02};
+
+    csum = *( ((uint16_t *)raw_tcp) + 8);
+
+    FAIL_IF(TCPChecksum((uint16_t *)raw_ipshdr,
+            (uint16_t *)raw_tcp, sizeof(raw_tcp), csum) != 0);
+    PASS;
+}
+
+static int TCPCalculateInvalidChecksumtest02(void)
+{
+    uint16_t csum = 0;
+
+    uint8_t raw_ipshdr[] = {
+        0x40, 0x8e, 0x7e, 0xb2, 0xc0, 0xa8, 0x01, 0x03};
+
+    uint8_t raw_tcp[] = {
+        0x00, 0x50, 0x8e, 0x16, 0x0d, 0x59, 0xcd, 0x3c,
+        0xcf, 0x0d, 0x21, 0x80, 0xa0, 0x12, 0x16, 0xa0,
+        0xfa, 0x03, 0x00, 0x00, 0x02, 0x04, 0x05, 0xb4,
+        0x04, 0x02, 0x08, 0x0a, 0x6e, 0x18, 0x78, 0x73,
+        0x01, 0x71, 0x74, 0xde, 0x01, 0x03, 0x03, 03};
+
+    csum = *( ((uint16_t *)raw_tcp) + 8);
+
+    FAIL_IF(TCPChecksum((uint16_t *) raw_ipshdr,
+            (uint16_t *)raw_tcp, sizeof(raw_tcp), csum) == 0);
+    PASS;
+}
+
+static int TCPV6CalculateValidChecksumtest03(void)
+{
+    uint16_t csum = 0;
+
+    static uint8_t raw_ipv6[] = {
+        0x00, 0x60, 0x97, 0x07, 0x69, 0xea, 0x00, 0x00,
+        0x86, 0x05, 0x80, 0xda, 0x86, 0xdd, 0x60, 0x00,
+        0x00, 0x00, 0x00, 0x20, 0x06, 0x40, 0x3f, 0xfe,
+        0x05, 0x07, 0x00, 0x00, 0x00, 0x01, 0x02, 0x00,
+        0x86, 0xff, 0xfe, 0x05, 0x80, 0xda, 0x3f, 0xfe,
+        0x05, 0x01, 0x04, 0x10, 0x00, 0x00, 0x02, 0xc0,
+        0xdf, 0xff, 0xfe, 0x47, 0x03, 0x3e, 0x03, 0xfe,
+        0x00, 0x16, 0xd6, 0x76, 0xf5, 0x2d, 0x0c, 0x7a,
+        0x08, 0x77, 0x80, 0x10, 0x21, 0x5c, 0xc2, 0xf1,
+        0x00, 0x00, 0x01, 0x01, 0x08, 0x0a, 0x00, 0x08,
+        0xca, 0x5a, 0x00, 0x01, 0x69, 0x27};
+
+    csum = *( ((uint16_t *)(raw_ipv6 + 70)));
+
+    FAIL_IF(TCPV6Checksum((uint16_t *)(raw_ipv6 + 14 + 8),
+            (uint16_t *)(raw_ipv6 + 54), 32, csum) != 0);
+    PASS;
+}
+
+static int TCPV6CalculateInvalidChecksumtest04(void)
+{
+    uint16_t csum = 0;
+
+    static uint8_t raw_ipv6[] = {
+        0x00, 0x60, 0x97, 0x07, 0x69, 0xea, 0x00, 0x00,
+        0x86, 0x05, 0x80, 0xda, 0x86, 0xdd, 0x60, 0x00,
+        0x00, 0x00, 0x00, 0x20, 0x06, 0x40, 0x3f, 0xfe,
+        0x05, 0x07, 0x00, 0x00, 0x00, 0x01, 0x02, 0x00,
+        0x86, 0xff, 0xfe, 0x05, 0x80, 0xda, 0x3f, 0xfe,
+        0x05, 0x01, 0x04, 0x10, 0x00, 0x00, 0x02, 0xc0,
+        0xdf, 0xff, 0xfe, 0x47, 0x03, 0x3e, 0x03, 0xfe,
+        0x00, 0x16, 0xd6, 0x76, 0xf5, 0x2d, 0x0c, 0x7a,
+        0x08, 0x77, 0x80, 0x10, 0x21, 0x5c, 0xc2, 0xf1,
+        0x00, 0x00, 0x01, 0x01, 0x08, 0x0a, 0x00, 0x08,
+        0xca, 0x5a, 0x00, 0x01, 0x69, 0x28};
+
+    csum = *( ((uint16_t *)(raw_ipv6 + 70)));
+
+    FAIL_IF(TCPV6Checksum((uint16_t *)(raw_ipv6 + 14 + 8),
+            (uint16_t *)(raw_ipv6 + 54), 32, csum) == 0);
+    PASS;
+}
+
+/** \test Get the wscale of 2 */
+static int TCPGetWscaleTest01(void)
+{
+    int retval = 0;
+    static uint8_t raw_tcp[] = {0xda, 0xc1, 0x00, 0x50, 0xb6, 0x21, 0x7f, 0x58,
+                                0x00, 0x00, 0x00, 0x00, 0xa0, 0x02, 0x16, 0xd0,
+                                0x8a, 0xaf, 0x00, 0x00, 0x02, 0x04, 0x05, 0xb4,
+                                0x04, 0x02, 0x08, 0x0a, 0x00, 0x62, 0x88, 0x28,
+                                0x00, 0x00, 0x00, 0x00, 0x01, 0x03, 0x03, 0x02};
+    Packet *p = PacketGetFromAlloc();
+    if (unlikely(p == NULL))
+        return 0;
+    IPV4Hdr ip4h;
+    ThreadVars tv;
+    DecodeThreadVars dtv;
+
+    memset(&tv, 0, sizeof(ThreadVars));
+    memset(&dtv, 0, sizeof(DecodeThreadVars));
+    memset(&ip4h, 0, sizeof(IPV4Hdr));
+
+    p->src.family = AF_INET;
+    p->dst.family = AF_INET;
+    p->ip4h = &ip4h;
+
+
+    FlowInitConfig(FLOW_QUIET);
+    DecodeTCP(&tv, &dtv, p, raw_tcp, sizeof(raw_tcp));
+
+    if (p->tcph == NULL) {
+        printf("tcp packet decode failed: ");
+        goto end;
+    }
+
+    uint8_t wscale = TCP_GET_WSCALE(p);
+    if (wscale != 2) {
+        printf("wscale %"PRIu8", expected 2: ", wscale);
+        goto end;
+    }
+
+    retval = 1;
+end:
+    PacketRecycle(p);
+    FlowShutdown();
+    SCFree(p);
+    return retval;
+}
+
+/** \test Get the wscale of 15, so see if return 0 properly */
+static int TCPGetWscaleTest02(void)
+{
+    int retval = 0;
+    static uint8_t raw_tcp[] = {0xda, 0xc1, 0x00, 0x50, 0xb6, 0x21, 0x7f, 0x58,
+                                0x00, 0x00, 0x00, 0x00, 0xa0, 0x02, 0x16, 0xd0,
+                                0x8a, 0xaf, 0x00, 0x00, 0x02, 0x04, 0x05, 0xb4,
+                                0x04, 0x02, 0x08, 0x0a, 0x00, 0x62, 0x88, 0x28,
+                                0x00, 0x00, 0x00, 0x00, 0x01, 0x03, 0x03, 0x0f};
+    Packet *p = PacketGetFromAlloc();
+    if (unlikely(p == NULL))
+        return 0;
+    IPV4Hdr ip4h;
+    ThreadVars tv;
+    DecodeThreadVars dtv;
+
+    memset(&tv, 0, sizeof(ThreadVars));
+    memset(&dtv, 0, sizeof(DecodeThreadVars));
+    memset(&ip4h, 0, sizeof(IPV4Hdr));
+
+    p->src.family = AF_INET;
+    p->dst.family = AF_INET;
+    p->ip4h = &ip4h;
+
+    FlowInitConfig(FLOW_QUIET);
+    DecodeTCP(&tv, &dtv, p, raw_tcp, sizeof(raw_tcp));
+
+    if (p->tcph == NULL) {
+        printf("tcp packet decode failed: ");
+        goto end;
+    }
+
+    uint8_t wscale = TCP_GET_WSCALE(p);
+    if (wscale != 0) {
+        printf("wscale %"PRIu8", expected 0: ", wscale);
+        goto end;
+    }
+
+    retval = 1;
+end:
+    PacketRecycle(p);
+    FlowShutdown();
+    SCFree(p);
+    return retval;
+}
+
+/** \test Get the wscale, but it's missing, so see if return 0 properly */
+static int TCPGetWscaleTest03(void)
+{
+    int retval = 0;
+    static uint8_t raw_tcp[] = {0xda, 0xc1, 0x00, 0x50, 0xb6, 0x21, 0x7f, 0x59,
+                                0xdd, 0xa3, 0x6f, 0xf8, 0x80, 0x10, 0x05, 0xb4,
+                                0x7c, 0x70, 0x00, 0x00, 0x01, 0x01, 0x08, 0x0a,
+                                0x00, 0x62, 0x88, 0x9e, 0x00, 0x00, 0x00, 0x00};
+    Packet *p = PacketGetFromAlloc();
+    if (unlikely(p == NULL))
+        return 0;
+    IPV4Hdr ip4h;
+    ThreadVars tv;
+    DecodeThreadVars dtv;
+
+    memset(&tv, 0, sizeof(ThreadVars));
+    memset(&dtv, 0, sizeof(DecodeThreadVars));
+    memset(&ip4h, 0, sizeof(IPV4Hdr));
+
+    p->src.family = AF_INET;
+    p->dst.family = AF_INET;
+    p->ip4h = &ip4h;
+
+    FlowInitConfig(FLOW_QUIET);
+    DecodeTCP(&tv, &dtv, p, raw_tcp, sizeof(raw_tcp));
+
+    if (p->tcph == NULL) {
+        printf("tcp packet decode failed: ");
+        goto end;
+    }
+
+    uint8_t wscale = TCP_GET_WSCALE(p);
+    if (wscale != 0) {
+        printf("wscale %"PRIu8", expected 0: ", wscale);
+        goto end;
+    }
+
+    retval = 1;
+end:
+    PacketRecycle(p);
+    FlowShutdown();
+    SCFree(p);
+    return retval;
+}
+
+static int TCPGetSackTest01(void)
+{
+    int retval = 0;
+    static uint8_t raw_tcp[] = {
+        0x00, 0x50, 0x06, 0xa6, 0xfa, 0x87, 0x0b, 0xf5,
+        0xf1, 0x59, 0x02, 0xe0, 0xa0, 0x10, 0x3e, 0xbc,
+        0x1d, 0xe7, 0x00, 0x00, 0x01, 0x01, 0x05, 0x12,
+        0xf1, 0x59, 0x13, 0xfc, 0xf1, 0x59, 0x1f, 0x64,
+        0xf1, 0x59, 0x08, 0x94, 0xf1, 0x59, 0x0e, 0x48 };
+    static uint8_t raw_tcp_sack[] = {
+        0xf1, 0x59, 0x13, 0xfc, 0xf1, 0x59, 0x1f, 0x64,
+        0xf1, 0x59, 0x08, 0x94, 0xf1, 0x59, 0x0e, 0x48 };
+    Packet *p = PacketGetFromAlloc();
+    if (unlikely(p == NULL))
+        return 0;
+    IPV4Hdr ip4h;
+    ThreadVars tv;
+    DecodeThreadVars dtv;
+
+    memset(&tv, 0, sizeof(ThreadVars));
+    memset(&dtv, 0, sizeof(DecodeThreadVars));
+    memset(&ip4h, 0, sizeof(IPV4Hdr));
+
+    p->src.family = AF_INET;
+    p->dst.family = AF_INET;
+    p->ip4h = &ip4h;
+
+    FlowInitConfig(FLOW_QUIET);
+    DecodeTCP(&tv, &dtv, p, raw_tcp, sizeof(raw_tcp));
+
+    if (p->tcph == NULL) {
+        printf("tcp packet decode failed: ");
+        goto end;
+    }
+
+    if (!TCP_HAS_SACK(p)) {
+        printf("tcp packet sack not decoded: ");
+        goto end;
+    }
+
+    int sack = TCP_GET_SACK_CNT(p);
+    if (sack != 2) {
+        printf("expected 2 sack records, got %u: ", TCP_GET_SACK_CNT(p));
+        goto end;
+    }
+
+    const uint8_t *sackptr = TCP_GET_SACK_PTR(p);
+    if (sackptr == NULL) {
+        printf("no sack data: ");
+        goto end;
+    }
+
+    if (memcmp(sackptr, raw_tcp_sack, 16) != 0) {
+        printf("malformed sack data: ");
+        goto end;
+    }
+
+    retval = 1;
+end:
+    PacketRecycle(p);
+    FlowShutdown();
+    SCFree(p);
+    return retval;
+}
+#endif /* UNITTESTS */
+
+void DecodeTCPRegisterTests(void)
+{
+#ifdef UNITTESTS
+    UtRegisterTest("TCPCalculateValidChecksumtest01",
+                   TCPCalculateValidChecksumtest01);
+    UtRegisterTest("TCPCalculateInvalidChecksumtest02",
+                   TCPCalculateInvalidChecksumtest02);
+    UtRegisterTest("TCPV6CalculateValidChecksumtest03",
+                   TCPV6CalculateValidChecksumtest03);
+    UtRegisterTest("TCPV6CalculateInvalidChecksumtest04",
+                   TCPV6CalculateInvalidChecksumtest04);
+    UtRegisterTest("TCPGetWscaleTest01", TCPGetWscaleTest01);
+    UtRegisterTest("TCPGetWscaleTest02", TCPGetWscaleTest02);
+    UtRegisterTest("TCPGetWscaleTest03", TCPGetWscaleTest03);
+    UtRegisterTest("TCPGetSackTest01", TCPGetSackTest01);
+#endif /* UNITTESTS */
+}
+/**
+ * @}
+ */