flow/pkts: allow matching on either direction

For flow.bytes and flow.pkts keywords, allow matching in either direction. Feature 5646
OISF · Dec 2, 2024 · 20a6627 · 20a6627
1 parent 85c8871
commit 20a6627
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diff --git a/doc/userguide/rules/flow-keywords.rst b/doc/userguide/rules/flow-keywords.rst
@@ -331,6 +331,8 @@ following directions:
 
 * toserver
 
+* either
+
 Syntax::
 
  flow.pkts:<direction>,[op]<number>
@@ -339,6 +341,7 @@ The number of packets can be matched exactly, or compared using the _op_ setting
 
  flow.pkts:toclient,3    # exactly 3
  flow.pkts:toserver,<3   # smaller than 3
+ flow.pkts:either,>=2  # greater than or equal to 2
 
 Signature example::
 
@@ -358,6 +361,8 @@ following directions:
 
 * toserver
 
+* either
+
 Syntax::
 
  flow.bytes:<direction>,[op]<number>
@@ -366,6 +371,7 @@ The number of bytes can be matched exactly, or compared using the _op_ setting::
 
  flow.bytes:toclient,3    # exactly 3
  flow.bytes:toserver,<3   # smaller than 3
+ flow.bytes:either,>=2  # greater than or equal to 2
 
 Signature example::
 

diff --git a/src/detect-flow-pkts.c b/src/detect-flow-pkts.c
@@ -26,6 +26,7 @@
 enum FlowDirection {
     DETECT_FLOW_TOSERVER = 1,
     DETECT_FLOW_TOCLIENT,
+    DETECT_FLOW_TOEITHER,
 };
 
 typedef struct DetectFlow_ {
@@ -46,6 +47,11 @@ static int DetectFlowPktsMatch(
         return DetectU32Match(p->flow->todstpktcnt, df->pkt_data);
     } else if (df->dir == DETECT_FLOW_TOCLIENT) {
         return DetectU32Match(p->flow->tosrcpktcnt, df->pkt_data);
+    } else if (df->dir == DETECT_FLOW_TOEITHER) {
+        if (DetectU32Match(p->flow->tosrcpktcnt, df->pkt_data)) {
+            return 1;
+        }
+        return DetectU32Match(p->flow->todstpktcnt, df->pkt_data);
     }
     return 0;
 }
@@ -133,6 +139,8 @@ static int DetectFlowPktsSetup(DetectEngineCtx *de_ctx, Signature *s, const char
             dir = DETECT_FLOW_TOSERVER;
         } else if (strcmp(token, "toclient") == 0) {
             dir = DETECT_FLOW_TOCLIENT;
+        } else if (strcmp(token, "either") == 0) {
+            dir = DETECT_FLOW_TOEITHER;
         }
 
         if (dir) {
@@ -243,6 +251,11 @@ static int DetectFlowBytesMatch(
         return DetectU64Match(p->flow->todstbytecnt, df->byte_data);
     } else if (df->dir == DETECT_FLOW_TOCLIENT) {
         return DetectU64Match(p->flow->tosrcbytecnt, df->byte_data);
+    } else if (df->dir == DETECT_FLOW_TOEITHER) {
+        if (DetectU64Match(p->flow->tosrcbytecnt, df->byte_data)) {
+            return 1;
+        }
+        return DetectU64Match(p->flow->todstbytecnt, df->byte_data);
     }
     return 0;
 }
@@ -330,6 +343,8 @@ static int DetectFlowBytesSetup(DetectEngineCtx *de_ctx, Signature *s, const cha
             dir = DETECT_FLOW_TOSERVER;
         } else if (strcmp(token, "toclient") == 0) {
             dir = DETECT_FLOW_TOCLIENT;
+        } else if (strcmp(token, "either") == 0) {
+            dir = DETECT_FLOW_TOEITHER;
         }
 
         if (dir) {