package output import ( "fmt" "github.com/maride/pancap/common" "io/ioutil" "log" "os" "strings" ) var ( registeredFiles []File notFound []string extractedFiles int ) // Registers a file with the given name and content. // This function takes care of filesystem I/O handling and flag parsing. // This means that a module should _always_ call this function when a file is encountered. // origin is a descriptive string where the file comes from, e.g. the module name. func RegisterFile(filename string, content []byte, origin string) { thisFile := NewFile(filename, content, origin) // To avoid doubles, we need to check if that hash is already present for _, f := range registeredFiles { if f.hash == thisFile.hash { // Found - stop here log.Printf("Avoided registering file '%s' because it has the same content as an already registered file ", f.name) return } } // None found, add to list registeredFiles = append(registeredFiles, thisFile) } // Iterates over all registered files and checks if they should be extracted and stored, and does exactly that. func StoreFiles() { var filesToExtract []File // Check different flag scenarios if *targetAllFiles { // We should extract all files. filesToExtract = registeredFiles } else { // We should extract only a given set of files fileList := strings.Split(*targetFiles, ",") for _, f := range fileList { // Iterate over desired files found := false for _, a := range registeredFiles { // Iterate over available (registered) files if f == a.hash { // Found the file found = true filesToExtract = append(filesToExtract, a) break } } if !found { // No file found, notify user notFound = append(notFound, fmt.Sprintf("File with hash %s requested but not found.", f)) } } } // Iterate over all target files and write it them out for _, f := range filesToExtract { writeOut(f) } } // Writes the given file object to disk, along with a stats file placed next to it. func writeOut(f File) { targetName := fmt.Sprintf("%s%c%s", *targetOutput, os.PathSeparator, f.hash) targetDescName := fmt.Sprintf("%s.info", targetName) targetDescription := fmt.Sprintf("Filename: %s\nHash: %s\nOrigin: %s\nSize: %d", f.name, f.hash, f.origin, len(f.content)) // Write target file targetWriteErr := ioutil.WriteFile(targetName, f.content, 0644) if targetWriteErr != nil { log.Printf("Unable to write file %s: %s", targetName, targetWriteErr.Error()) return } // Write stats file statsWriteErr := ioutil.WriteFile(targetDescName, []byte(targetDescription), 0644) if statsWriteErr != nil { log.Printf("Unable to write file %s: %s", targetName, targetWriteErr.Error()) return } // Raise stats extractedFiles++ } // Prints a brief summary about the extracted files func PrintSummary() { summary := fmt.Sprintf("%d files found in stream.\n%d files extracted from stream.", len(registeredFiles), extractedFiles) // Generate list of found files var strFileList []string for _, f := range registeredFiles { name := f.name if name == "" { name = "(no name found)" } strFileList = append(strFileList, fmt.Sprintf("%s: %s (%s), %d bytes", f.hash, name, f.origin, len(f.content))) } // Print list of files as a tree if len(strFileList) > 0 { summary += "\nFound files:" summary += "\n" + common.GenerateTree(strFileList) } // Check if we left a few requested files unanswered if len(notFound) > 0 { summary += "\nUnable to find requested file(s) " + strings.Join(notFound, ", ") } // Print constructed summary PrintBlock("Files", summary) }