final bad try

golang-fuzz/auth_fuzz.go

@@ -0,0 +1,39 @@
+package my_golang_fuzz
+
+import (
+	"bytes"
+
+	"linux-auth/internal/auth"
+	"linux-auth/internal/db"
+)
+
+func Fuzz(data []byte) int {
+	if err := db.Init("test_data.db"); err != nil {
+		return -1
+	}
+	defer db.Close()
+
+	parts := bytes.SplitN(data, []byte{0}, 2)
+	if len(parts) != 2 {
+		return 0
+	}
+
+	username := string(parts[0])
+	password := string(parts[1])
+
+	ok, err := auth.Authenticate(username, password)
+
+	if err != nil {
+		return -1
+	}
+
+	if ok {
+		if (username == "admin" && password == "admin123") ||
+			(username == "user1" && password == "password1") {
+			return 1
+		}
+		return -1
+	}
+
+	return 1
+}

golang-fuzz/auth_fuzz_golangfuzz_test.go

@@ -0,0 +1,38 @@
+// Code generated by golang-fuzz; DO NOT EDIT.
+
+package my_golang_fuzz
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func Fuzz_(f *testing.F) {
+	loadTestCases(f)
+	f.Fuzz(func(_ *testing.T, input []byte) { Fuzz(input) })
+}
+
+func loadTestCases(f *testing.F) {
+	dir, err := os.ReadDir(`corpus`)
+	if err != nil {
+		f.Logf(`Running without adding corpus: %s`, err)
+		return
+	}
+
+	if len(dir) == 0 {
+		f.Log(`Running without adding corpus: directory is empty`)
+	}
+
+	for _, corpus := range dir {
+		if corpus.IsDir() {
+			continue
+		}
+
+		input, err := os.ReadFile(filepath.Join(`corpus`, corpus.Name()))
+		if err != nil {
+			f.Logf(`Could not read corpus input %s: %s`, corpus.Name(), err)
+		}
+		f.Add(input)
+	}
+}

golang-fuzz/install_golang-fuzz.sh

@@ -0,0 +1,3 @@
+#!/bin/bash
+
+go install github.com/ultraware/golang-fuzz@latest

golang-fuzz/run_golang-fuzz.sh

@@ -0,0 +1,7 @@
+#!/bin/bash
+
+cp ../data/users.db test_data.db
+
+export PATH=$PATH:$(go env GOPATH)/bin
+
+golang-fuzz -gofuzz -run