test: add Docker-based build and smoke test environment

.github/workflows/docker-build.yml

@@ -0,0 +1,48 @@
+name: Docker build
+
+on:
+  push:
+    branches: [master]
+    paths:
+      - Dockerfile
+      - docker-compose.yml
+      - test-connector.sh
+      - src/**
+      - .github/workflows/docker-build.yml
+  pull_request:
+    paths:
+      - Dockerfile
+      - docker-compose.yml
+      - test-connector.sh
+      - src/**
+      - .github/workflows/docker-build.yml
+
+permissions:
+  contents: read
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  build-and-smoke-test:
+    name: Build and smoke test
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1  # v7.0.1
+        with:
+          persist-credentials: false
+
+      - name: Build image
+        run: docker build -t modsec3-apache-test .
+
+      - name: Run container
+        run: docker run -d -p 8080:8080 --name modsec3-test modsec3-apache-test
+
+      - name: Run smoke tests
+        run: ./test-connector.sh
+
+      - name: Show container logs
+        if: always()
+        run: docker logs modsec3-test

DOCKER_TEST.md

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+# Docker Testing Guide for ModSecurity Apache Connector
+
+This Docker setup tests the ModSecurity v3 Apache connector with all implemented fixes.
+
+## Quick Start
+
+```bash
+# Build and run
+docker build -t modsec3-apache-test .
+docker run -d -p 8080:8080 --name modsec3-test modsec3-apache-test
+
+# Or use docker-compose
+docker-compose up -d
+
+# Run automated tests
+./test-connector.sh
+```
+
+## Manual Testing
+
+```bash
+# Test 1: Normal request (should work - 200 OK)
+curl http://localhost:8080/
+
+# Test 2: Query string rule (should be blocked - 403 Forbidden)
+curl -v http://localhost:8080/?test=evil
+
+# Test 3: Request body rule (should be blocked - 403 Forbidden)
+curl -X POST http://localhost:8080/ -d "data=malicious"
+
+# Test 4: Large POST - tests multi-bucket processing (should work - 200 OK)
+curl -X POST http://localhost:8080/ -d "$(head -c 20000 /dev/zero | tr '\0' 'A')"
+
+# Test 5: Large POST with evil content (should be blocked - 403)
+# This specifically verifies the request body processing fix!
+curl -X POST http://localhost:8080/ -d "A$(head -c 15000 /dev/zero | tr '\0' 'A')malicious"
+```
+
+## Verifying the Fixes
+
+### ✅ Fix #1: Request Body Processing
+**Issue**: Rules fired multiple times (once per ~8KB bucket)
+**Fix**: Only call `msc_process_request_body()` once at EOS
+
+**Test**:
+```bash
+# Send large POST with "malicious" at the end
+curl -v -X POST http://localhost:8080/ -d "$(head -c 20000 /dev/zero | tr '\0' 'A')malicious"
+```
+**Expected**: HTTP 403 (proves rules evaluated the complete body correctly)
+
+### ✅ Fix #2: Status Code Control
+**Issue**: ModSecurity couldn't set status codes (missing `r->status`)
+**Fix**: Added `f->r->status = status;` before `status_line`
+
+**Test**:
+```bash
+curl -v http://localhost:8080/?test=evil
+```
+**Expected**: `HTTP/1.1 403 Forbidden` (not 400 or other)
+
+### ✅ Fix #3: Filter Removal
+**Issue**: Input filter called `ap_remove_output_filter()`
+**Fix**: Changed to `ap_remove_input_filter()`
+
+**Test**: Run all tests - no crashes
+
+### ✅ Fix #4: Error Handling
+**Issue**: `apr_bucket_read()` return value not checked
+**Fix**: Added error checking
+
+**Test**: Normal operation should work without errors
+
+## Debugging
+
+```bash
+# View live logs
+docker logs -f modsec3-test
+
+# Enter container
+docker exec -it modsec3-test bash
+
+# Check module loaded
+/usr/local/apache2/bin/apachectl -M | grep security3
+
+# Check module dependencies
+ldd /usr/local/apache2/modules/mod_security3.so
+
+# View ModSecurity config
+cat /etc/modsecurity/modsecurity.conf
+cat /etc/modsecurity/test-rules.conf
+```
+
+## Expected Results
+
+All 6 tests should pass:
+1. ✅ Normal request - 200 OK
+2. ✅ Query string block - 403 Forbidden
+3. ✅ Request body block - 403 Forbidden
+4. ✅ Normal POST - 200 OK
+5. ✅ Large POST (multi-bucket) - 200 OK
+6. ✅ Large POST with evil - 403 Forbidden (verifies the fix!)
+
+## What's Included
+
+- **libmodsecurity v3** (latest from v3/master branch)
+- **Apache HTTP Server 2.4.62**
+- **ModSecurity Apache Connector** with fixes:
+  - Request body processing (process once at EOS)
+  - Status code control (r->status properly set)
+  - Filter removal (correct function called)
+  - Error handling (return values checked)
+
+## Files Modified
+
+The following files contain our fixes:
+- `src/mod_security3.h` - Added `request_body_processed` flag
+- `src/mod_security3.c` - Initialize flag
+- `src/msc_filters.c` - Fixed request body processing, filter removal, error handling
+- `src/msc_utils.c` - Fixed status code bug
+
+See commit history or `/tmp/fixes_summary.md` for detailed changes.