BloomFilter test

bpf/src/test/java/me/bechberger/ebpf/bpf/BloomFilterMapTest.java

@@ -0,0 +1,90 @@
+package me.bechberger.ebpf.bpf;
+
+import me.bechberger.ebpf.annotations.bpf.BPF;
+import me.bechberger.ebpf.annotations.bpf.BPFMapDefinition;
+import me.bechberger.ebpf.bpf.map.BPFBloomFilter;
+import me.bechberger.ebpf.shared.TraceLog;
+import org.junit.jupiter.api.Test;
+
+import java.time.Duration;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class BloomFilterMapTest {
+
+    @BPF(license = "GPL")
+    public static abstract class Program extends BPFProgram {
+        @BPFMapDefinition(maxEntries = 256)
+        BPFBloomFilter<Integer> filter;
+
+        static final String EBPF_PROGRAM = """
+            #include <vmlinux.h>
+            #include <bpf/bpf_helpers.h>
+            #include <bpf/bpf_endian.h>
+
+            SEC ("kprobe/do_sys_openat2")
+                 int kprobe__do_sys_openat2 (struct pt_regs *ctx)
+            {
+              int placed_value = 12;
+              int placed_value_in_filter = bpf_map_lookup_elem(&filter, &placed_value);
+              if (placed_value_in_filter == 0) {
+                bpf_printk("Placed OK");
+              } else {
+                bpf_printk("Placed NOT OK");
+              }
+
+              int value = 11;
+              int maybe_in_filter = bpf_map_lookup_elem(&filter, &value);
+              if (maybe_in_filter != 0) {
+                bpf_printk("Before OK");
+              } else {
+                bpf_printk("Before NOT OK");
+              }
+
+              bpf_map_push_elem(&filter, &value, BPF_ANY);
+              maybe_in_filter = bpf_map_lookup_elem(&filter, &value);
+              if (maybe_in_filter == 0) {
+                bpf_printk("After OK");
+              } else {
+                bpf_printk("After NOT OK");
+              }
+              return 0;
+            }
+        """;
+    }
+
+    @Test
+    public void testBasicArrayMap() throws InterruptedException {
+        try (var program = BPFProgram.load(BloomFilterMapTest.Program.class)) {
+            var filter = program.filter;
+            filter.put(12);
+            program.autoAttachProgram(program.getProgramByName("kprobe__do_sys_openat2"));
+            TestUtil.triggerOpenAt();
+
+            while (true) {
+                var msg = program.readTraceFields().msg();
+                if (msg != null) {
+                    assertEquals("Placed OK", msg);
+                    break;
+                }
+            }
+
+            while (true) {
+                var msg = program.readTraceFields().msg();
+                if (msg != null) {
+                    assertEquals("Before OK", msg);
+                    break;
+                }
+            }
+
+            while (true) {
+                var msg = program.readTraceFields().msg();
+                if (msg != null) {
+                    assertEquals("After OK", msg);
+                    break;
+                }
+            }
+        }
+        TraceLog.getInstance().readAllAvailableLines(Duration.ofMillis(100));
+    }
+}