From 1a4765a3c645e17903db8f161fac1cf2eef82b4a Mon Sep 17 00:00:00 2001
From: wiaamm <wiaamm@checkpoint.com>
Date: Mon, 17 Nov 2025 20:38:25 +0200
Subject: [PATCH] fix response body

---
 .../open-appsec-waf-kong-plugin/handler.lua   | 95 ++++---------------
 1 file changed, 18 insertions(+), 77 deletions(-)

diff --git a/attachments/kong/plugins/open-appsec-waf-kong-plugin/handler.lua b/attachments/kong/plugins/open-appsec-waf-kong-plugin/handler.lua
index f86ded0..d73f4f2 100755
--- a/attachments/kong/plugins/open-appsec-waf-kong-plugin/handler.lua
+++ b/attachments/kong/plugins/open-appsec-waf-kong-plugin/handler.lua
@@ -180,17 +180,22 @@ function NanoHandler.body_filter(conf)
         return
     end
 
-    local body = kong.response.get_raw_body()
+    -- Get the current chunk from ngx.arg
+    local chunk = ngx.arg[1]
+    local eof = ngx.arg[2]
 
-    if body and #body > 0 then
+    -- Process body chunk if present
+    if chunk and #chunk > 0 then
         ctx.body_seen = true
-        local verdict, response, modifications = nano.send_body(session_id, session_data, body, nano.HttpChunkType.HTTP_RESPONSE_BODY)
+        kong.log.debug("Processing response body chunk, size: ", #chunk, " bytes, EOF: ", eof)
+        
+        local verdict, response, modifications = nano.send_body(session_id, session_data, chunk, nano.HttpChunkType.HTTP_RESPONSE_BODY)
 
         ctx.body_buffer_chunk = ctx.body_buffer_chunk or 0
 
         if modifications then
-            body = nano.handle_body_modifications(body, modifications, ctx.body_buffer_chunk)
-            kong.response.set_raw_body(body)
+            chunk = nano.handle_body_modifications(chunk, modifications, ctx.body_buffer_chunk)
+            ngx.arg[1] = chunk
         end
 
         ctx.body_buffer_chunk = ctx.body_buffer_chunk + 1
@@ -202,25 +207,14 @@ function NanoHandler.body_filter(conf)
             nano.cleanup_all()
             return result
         end
-        return
-    elseif ctx.expect_body then
-        kong.log.debug("Response body not in memory, attempting to read from buffer/file")
-
-        local body_data = ngx.var.response_body
-        if body_data and #body_data > 0 then
-            kong.log.debug("Found response body in nginx var, size: ", #body_data)
-            ctx.body_seen = true
-            local verdict, response, modifications = nano.send_body(session_id, session_data, body_data, nano.HttpChunkType.HTTP_RESPONSE_BODY)
-
-            ctx.body_buffer_chunk = ctx.body_buffer_chunk or 0
-
-            if modifications then
-                body_data = nano.handle_body_modifications(body_data, modifications, ctx.body_buffer_chunk)
-                kong.response.set_raw_body(body_data)
-            end
-
-            ctx.body_buffer_chunk = ctx.body_buffer_chunk + 1
+    end
 
+    -- Handle end of response
+    if eof then
+        kong.log.debug("Response body end of stream reached")
+        
+        if ctx.body_seen or ctx.expect_body == false then
+            local verdict, response = nano.end_inspection(session_id, session_data, nano.HttpChunkType.HTTP_RESPONSE_END)
             if verdict == nano.AttachmentVerdict.DROP then
                 nano.fini_session(session_data)
                 ctx.session_finalized = true
@@ -228,64 +222,11 @@ function NanoHandler.body_filter(conf)
                 nano.cleanup_all()
                 return result
             end
-            return
-        else
-            -- Try to read from response body file
-            local body_file = ngx.var.response_body_file
-            if body_file then
-                kong.log.debug("Reading response body from file: ", body_file)
-                local file = io.open(body_file, "rb")
-                if file then
-                    local entire_body = file:read("*all")
-                    file:close()
 
-                    if entire_body and #entire_body > 0 then
-                        kong.log.debug("Sending entire response body of size ", #entire_body, " bytes to C module")
-                        ctx.body_seen = true
-                        local verdict, response, modifications = nano.send_body(session_id, session_data, entire_body, nano.HttpChunkType.HTTP_RESPONSE_BODY)
-
-                        ctx.body_buffer_chunk = ctx.body_buffer_chunk or 0
-
-                        if modifications then
-                            entire_body = nano.handle_body_modifications(entire_body, modifications, ctx.body_buffer_chunk)
-                            kong.response.set_raw_body(entire_body)
-                        end
-
-                        ctx.body_buffer_chunk = ctx.body_buffer_chunk + 1
-
-                        if verdict == nano.AttachmentVerdict.DROP then
-                            nano.fini_session(session_data)
-                            ctx.session_finalized = true
-                            local result = nano.handle_custom_response(session_data, response)
-                            nano.cleanup_all()
-                            return result
-                        end
-                        return
-                    end
-                else
-                    kong.log.warn("Failed to open response body file: ", body_file)
-                end
-            else
-                kong.log.debug("Response body expected but no body data or file available")
-            end
-        end
-    end
-
-    if ctx.body_seen or ctx.expect_body == false then
-        local verdict, response = nano.end_inspection(session_id, session_data, nano.HttpChunkType.HTTP_RESPONSE_END)
-        if verdict == nano.AttachmentVerdict.DROP then
             nano.fini_session(session_data)
-            ctx.session_finalized = true
-            local result = nano.handle_custom_response(session_data, response)
-            -- Clean up allocated memory
             nano.cleanup_all()
-            return result
+            ctx.session_finalized = true
         end
-
-        nano.fini_session(session_data)
-        -- Clean up allocated memory
-        nano.cleanup_all()
-        ctx.session_finalized = true
     end
 end