diff --git a/application.fam b/application.fam index 6a9652dc108..afdc73329da 100644 --- a/application.fam +++ b/application.fam @@ -9,4 +9,7 @@ App( fap_category="Tools", fap_icon="icons/passgen_icon.png", fap_icon_assets="icons", + fap_author="@anakod & @henrygab", + fap_version="1.1", + fap_description="Simple password generator", ) diff --git a/passgen.c b/passgen.c index d479545f8c9..7585eda26d4 100644 --- a/passgen.c +++ b/passgen.c @@ -1,18 +1,19 @@ #include +#include #include #include #include #include #include #include -#include #define PASSGEN_MAX_LENGTH 16 +#define PASSGEN_CHARACTERS_LENGTH (26 * 4) #define PASSGEN_DIGITS "0123456789" #define PASSGEN_LETTERS_LOW "abcdefghijklmnopqrstuvwxyz" #define PASSGEN_LETTERS_UP "ABCDEFGHIJKLMNOPQRSTUVWXYZ" -#define PASSGEN_SPECIAL "!#$%%^&*.-_" +#define PASSGEN_SPECIAL "!#$%^&*.-_" typedef enum PassGen_Alphabet { Digits = 1, @@ -26,6 +27,25 @@ typedef enum PassGen_Alphabet { Mixed = DigitsAllLetters | Special } PassGen_Alphabet; +const char* const PassGen_AlphabetChars[16] = { + "0", // invalid value + /* PASSGEN_SPECIAL PASSGEN_LETTERS_UP PASSGEN_LETTERS_LOW */ PASSGEN_DIGITS, + /* PASSGEN_SPECIAL PASSGEN_LETTERS_UP */ PASSGEN_LETTERS_LOW /* PASSGEN_DIGITS */, + /* PASSGEN_SPECIAL PASSGEN_LETTERS_UP */ PASSGEN_LETTERS_LOW PASSGEN_DIGITS, + /* PASSGEN_SPECIAL */ PASSGEN_LETTERS_UP /* PASSGEN_LETTERS_LOW PASSGEN_DIGITS */, + /* PASSGEN_SPECIAL */ PASSGEN_LETTERS_UP /* PASSGEN_LETTERS_LOW */ PASSGEN_DIGITS, + /* PASSGEN_SPECIAL */ PASSGEN_LETTERS_UP PASSGEN_LETTERS_LOW /* PASSGEN_DIGITS */, + /* PASSGEN_SPECIAL */ PASSGEN_LETTERS_UP PASSGEN_LETTERS_LOW PASSGEN_DIGITS, + PASSGEN_SPECIAL /* PASSGEN_LETTERS_UP PASSGEN_LETTERS_LOW PASSGEN_DIGITS */, + PASSGEN_SPECIAL /* PASSGEN_LETTERS_UP PASSGEN_LETTERS_LOW */ PASSGEN_DIGITS, + PASSGEN_SPECIAL /* PASSGEN_LETTERS_UP */ PASSGEN_LETTERS_LOW /* PASSGEN_DIGITS */, + PASSGEN_SPECIAL /* PASSGEN_LETTERS_UP */ PASSGEN_LETTERS_LOW PASSGEN_DIGITS, + PASSGEN_SPECIAL PASSGEN_LETTERS_UP /* PASSGEN_LETTERS_LOW PASSGEN_DIGITS */, + PASSGEN_SPECIAL PASSGEN_LETTERS_UP /* PASSGEN_LETTERS_LOW */ PASSGEN_DIGITS, + PASSGEN_SPECIAL PASSGEN_LETTERS_UP PASSGEN_LETTERS_LOW /* PASSGEN_DIGITS */, + PASSGEN_SPECIAL PASSGEN_LETTERS_UP PASSGEN_LETTERS_LOW PASSGEN_DIGITS, +}; + const int AlphabetLevels[] = {Digits, Lowercase, DigitsLower, DigitsAllLetters, Mixed}; const char* AlphabetLevelNames[] = {"1234", "abcd", "ab12", "Ab12", "Ab1#"}; const int AlphabetLevelsCount = sizeof(AlphabetLevels) / sizeof(int); @@ -44,21 +64,24 @@ typedef struct { Gui* gui; FuriMutex** mutex; NotificationApp* notify; + const char* alphabet; char password[PASSGEN_MAX_LENGTH + 1]; - // char alphabet[PASSGEN_CHARACTERS_LENGTH + 1]; - FuriString* alphabet; - int length; + int length; // must be <= PASSGEN_MAX_LENGTH int level; } PassGen; void state_free(PassGen* app) { + // NOTE: would have preferred if a "safe" memset() was available... + // but, since cannot prevent optimization from removing + // memset(), fill with random data instead. + furi_hal_random_fill_buf((void*)(app->password), PASSGEN_MAX_LENGTH); + gui_remove_view_port(app->gui, app->view_port); furi_record_close(RECORD_GUI); view_port_free(app->view_port); furi_message_queue_free(app->input_queue); furi_mutex_free(app->mutex); furi_record_close(RECORD_NOTIFICATION); - furi_string_free(app->alphabet); free(app); } @@ -100,17 +123,19 @@ static void render_callback(Canvas* canvas, void* ctx) { void build_alphabet(PassGen* app) { PassGen_Alphabet mode = AlphabetLevels[app->level]; - if((mode & Digits) != 0) furi_string_cat(app->alphabet, PASSGEN_DIGITS); - if((mode & Lowercase) != 0) furi_string_cat(app->alphabet, PASSGEN_LETTERS_LOW); - if((mode & Uppercase) != 0) furi_string_cat(app->alphabet, PASSGEN_LETTERS_UP); - if((mode & Special) != 0) furi_string_cat(app->alphabet, PASSGEN_SPECIAL); + if(mode > 0 && mode < 16) { + app->alphabet = PassGen_AlphabetChars[mode]; + } else { + app->alphabet = + PassGen_AlphabetChars[0]; // Invalid mode ... password will be all zero digits + } } PassGen* state_init() { PassGen* app = malloc(sizeof(PassGen)); + _Static_assert(8 <= PASSGEN_MAX_LENGTH, "app->length must be set <= PASSGEN_MAX_LENGTH"); app->length = 8; app->level = 2; - app->alphabet = furi_string_alloc(); build_alphabet(app); app->input_queue = furi_message_queue_alloc(8, sizeof(InputEvent)); app->view_port = view_port_alloc(); @@ -126,12 +151,46 @@ PassGen* state_init() { } void generate(PassGen* app) { - int hi = furi_string_size(app->alphabet); - for(int i = 0; i < app->length; i++) { - int x = rand() % hi; - app->password[i] = furi_string_get_char(app->alphabet, x); + memset(app->password, 0, PASSGEN_MAX_LENGTH + 1); + + int char_option_count = strlen(app->alphabet); + if(char_option_count < 0) { + return; + } + + // determine largest character value that avoids bias + char ceil = CHAR_MAX - (CHAR_MAX % char_option_count) - 1; + + // iteratively fill the password buffer with random values + // then keep only values that are in-range (no bias) + void* remaining_buffer = app->password; + size_t remaining_length = (app->length * sizeof(char)); + + while(remaining_length != 0) { + // fewer calls to hardware TRNG is more efficient + furi_hal_random_fill_buf(remaining_buffer, remaining_length); + + // keep only values that are in-range (no bias) + char* target = remaining_buffer; + char* source = remaining_buffer; + size_t valid_count = 0; + + for(size_t i = 0; i < remaining_length; i++) { + int v = *source; + // if the generated random value is in range, keep it + if(v < ceil) { + v %= char_option_count; + *target = app->alphabet[v]; + // increment target pointer and count of valid items found + target++; + valid_count++; + } + // always increment the source pointer + source++; + } + remaining_length -= valid_count; + remaining_buffer = target; } - app->password[app->length] = '\0'; } void update_password(PassGen* app, bool vibro) {