eve: revert ethernet addresses when needed

EVE logging has a direction parameter that can cause the logging
of an application layer to be done in a direction that is not linked
to the packet. As a result the source IP addres could be assigned the
MAC address of the destination IP and reverse.

This patch addresses this by propagating the direction to the ethernet
logging function and using it there to define the correct mapping.

Issue #6405

src/output-json-flow.c

@@ -281,7 +281,7 @@ static void EveFlowLogJSON(OutputJsonThreadCtx *aft, JsonBuilder *jb, Flow *f)
     /* Close flow. */
     jb_close(jb);
 
-    EveAddCommonOptions(&aft->ctx->cfg, NULL, f, jb);
+    EveAddCommonOptions(&aft->ctx->cfg, NULL, f, jb, LOG_DIR_FLOW);
 
     /* TCP */
     if (f->proto == IPPROTO_TCP) {

src/output-json-netflow.c

@@ -275,7 +275,7 @@ static int JsonNetFlowLogger(ThreadVars *tv, void *thread_data, Flow *f)
     if (unlikely(jb == NULL))
         return TM_ECODE_OK;
     NetFlowLogEveToServer(jb, f);
-    EveAddCommonOptions(&jhl->ctx->cfg, NULL, f, jb);
+    EveAddCommonOptions(&jhl->ctx->cfg, NULL, f, jb, LOG_DIR_FLOW_TOSERVER);
     OutputJsonBuilderBuffer(jb, jhl);
     jb_free(jb);
 
@@ -285,7 +285,7 @@ static int JsonNetFlowLogger(ThreadVars *tv, void *thread_data, Flow *f)
         if (unlikely(jb == NULL))
             return TM_ECODE_OK;
         NetFlowLogEveToClient(jb, f);
-        EveAddCommonOptions(&jhl->ctx->cfg, NULL, f, jb);
+        EveAddCommonOptions(&jhl->ctx->cfg, NULL, f, jb, LOG_DIR_FLOW_TOCLIENT);
         OutputJsonBuilderBuffer(jb, jhl);
         jb_free(jb);
     }

src/output-json.c

@@ -70,7 +70,8 @@
 
 static void OutputJsonDeInitCtx(OutputCtx *);
 static void CreateEveCommunityFlowId(JsonBuilder *js, const Flow *f, const uint16_t seed);
-static int CreateJSONEther(JsonBuilder *parent, const Packet *p, const Flow *f);
+static int CreateJSONEther(
+        JsonBuilder *parent, const Packet *p, const Flow *f, enum OutputJsonLogDirection dir);
 
 static const char *TRAFFIC_ID_PREFIX = "traffic/id/";
 static const char *TRAFFIC_LABEL_PREFIX = "traffic/label/";
@@ -404,14 +405,14 @@ void EveAddMetadata(const Packet *p, const Flow *f, JsonBuilder *js)
     }
 }
 
-void EveAddCommonOptions(const OutputJsonCommonSettings *cfg,
+void EveAddCommonOptions(const OutputJsonCommonSettings *cfg, const Packet *p, const Flow *f,
-        const Packet *p, const Flow *f, JsonBuilder *js)
+        JsonBuilder *js, enum OutputJsonLogDirection dir)
 {
     if (cfg->include_metadata) {
         EveAddMetadata(p, f, js);
     }
     if (cfg->include_ethernet) {
-        CreateJSONEther(js, p, f);
+        CreateJSONEther(js, p, f, dir);
     }
     if (cfg->include_community_id && f != NULL) {
         CreateEveCommunityFlowId(js, f, cfg->community_id_seed);
@@ -735,15 +736,43 @@ static int MacSetIterateToJSON(uint8_t *val, MacSetSide side, void *data)
     return 0;
 }
 
-static int CreateJSONEther(JsonBuilder *js, const Packet *p, const Flow *f)
+static int CreateJSONEther(
+        JsonBuilder *js, const Packet *p, const Flow *f, enum OutputJsonLogDirection dir)
 {
     if (p != NULL) {
         /* this is a packet context, so we need to add scalar fields */
         if (PacketIsEthernet(p)) {
             const EthernetHdr *ethh = PacketGetEthernet(p);
             jb_open_object(js, "ether");
-            const uint8_t *src = ethh->eth_src;
+            const uint8_t *src;
-            const uint8_t *dst = ethh->eth_dst;
+            const uint8_t *dst;
+            switch (dir) {
+                case LOG_DIR_FLOW_TOSERVER:
+                    // fallthrough
+                case LOG_DIR_FLOW:
+                    if (PKT_IS_TOCLIENT(p)) {
+                        src = ethh->eth_dst;
+                        dst = ethh->eth_src;
+                    } else {
+                        src = ethh->eth_src;
+                        dst = ethh->eth_dst;
+                    }
+                    break;
+                case LOG_DIR_FLOW_TOCLIENT:
+                    if (PKT_IS_TOSERVER(p)) {
+                        src = ethh->eth_dst;
+                        dst = ethh->eth_src;
+                    } else {
+                        src = ethh->eth_src;
+                        dst = ethh->eth_dst;
+                    }
+                    break;
+                case LOG_DIR_PACKET:
+                default:
+                    src = ethh->eth_src;
+                    dst = ethh->eth_dst;
+                    break;
+            }
             JSONFormatAndAddMACAddr(js, "src_mac", src, false);
             JSONFormatAndAddMACAddr(js, "dest_mac", dst, false);
             jb_close(js);
@@ -767,8 +796,15 @@ static int CreateJSONEther(JsonBuilder *js, const Packet *p, const Flow *f)
             }
             jb_close(info.dst);
             jb_close(info.src);
+            /* case is handling netflow too so may need to revert */
+            if (dir == LOG_DIR_FLOW_TOCLIENT) {
+                jb_set_object(js, "dest_macs", info.src);
+                jb_set_object(js, "src_macs", info.dst);
+            } else {
+                DEBUG_VALIDATE_BUG_ON(dir != LOG_DIR_FLOW_TOSERVER && dir != LOG_DIR_FLOW);
                 jb_set_object(js, "dest_macs", info.dst);
                 jb_set_object(js, "src_macs", info.src);
+            }
             jb_free(info.dst);
             jb_free(info.src);
             jb_close(js);
@@ -867,7 +903,7 @@ JsonBuilder *CreateEveHeader(const Packet *p, enum OutputJsonLogDirection dir,
     jb_set_string(js, "pkt_src", PktSrcToString(p->pkt_src));
 
     if (eve_ctx != NULL) {
-        EveAddCommonOptions(&eve_ctx->cfg, p, f, js);
+        EveAddCommonOptions(&eve_ctx->cfg, p, f, js, dir);
     }
 
     return js;

src/output-json.h

@@ -110,8 +110,8 @@ OutputInitResult OutputJsonLogInitSub(ConfNode *conf, OutputCtx *parent_ctx);
 TmEcode JsonLogThreadInit(ThreadVars *t, const void *initdata, void **data);
 TmEcode JsonLogThreadDeinit(ThreadVars *t, void *data);
 
-void EveAddCommonOptions(const OutputJsonCommonSettings *cfg,
+void EveAddCommonOptions(const OutputJsonCommonSettings *cfg, const Packet *p, const Flow *f,
-        const Packet *p, const Flow *f, JsonBuilder *js);
+        JsonBuilder *js, enum OutputJsonLogDirection dir);
 void EveAddMetadata(const Packet *p, const Flow *f, JsonBuilder *js);
 
 int OutputJSONMemBufferCallback(const char *str, size_t size, void *data);