diff options
Diffstat (limited to 'src/mnemonics/electrum-words.cpp')
| -rw-r--r-- | src/mnemonics/electrum-words.cpp | 97 |
1 files changed, 68 insertions, 29 deletions
diff --git a/src/mnemonics/electrum-words.cpp b/src/mnemonics/electrum-words.cpp index d1fae84cb..d48df1436 100644 --- a/src/mnemonics/electrum-words.cpp +++ b/src/mnemonics/electrum-words.cpp @@ -64,6 +64,7 @@ namespace const std::string LANGUAGES_DIRECTORY = "languages"; const std::string OLD_WORD_FILE = "old-word-list"; + const int unique_prefix_length = 4; /*! * \brief Tells if the module hasn't been initialized with a word list file. * \return true if the module hasn't been initialized with a word list file false otherwise. @@ -76,9 +77,10 @@ namespace /*! * \brief Create word list map and array data structres for use during inter-conversion between * words and secret key. - * \param word_file Path to the word list file from pwd. + * \param word_file Path to the word list file from pwd. + * \param has_checksum True if checksum was supplied false if not. */ - void create_data_structures(const std::string &word_file) + void create_data_structures(const std::string &word_file, bool has_checksum) { words_array.clear(); words_map.clear(); @@ -93,7 +95,15 @@ namespace while (input_stream >> word) { words_array.push_back(word); - words_map[word] = num_words; + if (has_checksum) + { + // Only if checksum was passed should we stick to just 4 char checks to be lenient about typos. + words_map[word.substr(0, unique_prefix_length)] = num_words; + } + else + { + words_map[word] = num_words; + } num_words++; } input_stream.close(); @@ -101,16 +111,27 @@ namespace /*! * \brief Tells if all the words passed in wlist was present in current word list file. - * \param wlist List of words to match. - * \return true if all the words were present false if not. + * \param wlist List of words to match. + * \param has_checksum If word list passed checksum test, we need to only do a 4 char check. + * \return true if all the words were present false if not. */ - bool word_list_file_match(const std::vector<std::string> &wlist) + bool word_list_file_match(const std::vector<std::string> &wlist, bool has_checksum) { for (std::vector<std::string>::const_iterator it = wlist.begin(); it != wlist.end(); it++) { - if (words_map.count(*it) == 0) + if (has_checksum) + { + if (words_map.count(it->substr(0, unique_prefix_length)) == 0) + { + return false; + } + } + else { - return false; + if (words_map.count(*it) == 0) + { + return false; + } } } return true; @@ -118,13 +139,19 @@ namespace /*! * \brief Creates a checksum index in the word list array on the list of words. - * \param words Space separated list of words - * \return Checksum index + * \param word_list Vector of words + * \return Checksum index */ - uint32_t create_checksum_index(const std::string &words) + uint32_t create_checksum_index(const std::vector<std::string> &word_list) { + std::string four_char_words = ""; + + for (std::vector<std::string>::const_iterator it = word_list.begin(); it != word_list.end(); it++) + { + four_char_words += it->substr(0, unique_prefix_length); + } boost::crc_32_type result; - result.process_bytes(words.data(), words.length()); + result.process_bytes(four_char_words.data(), four_char_words.length()); return result.checksum() % seed_length; } } @@ -144,21 +171,22 @@ namespace crypto namespace ElectrumWords { /*! - * \brief Called to initialize it work with a word list file. - * \param language Language of the word list file. - * \param old_word_list true it is to use the old style word list file false if not. + * \brief Called to initialize it to work with a word list file. + * \param language Language of the word list file. + * \param has_checksum True if the checksum was passed false if not. + * \param old_word_list true it is to use the old style word list file false if not. */ - void init(const std::string &language, bool old_word_list) + void init(const std::string &language, bool has_checksum, bool old_word_list) { if (old_word_list) { // Use the old word list file if told to. - create_data_structures(WORD_LISTS_DIRECTORY + '/' + OLD_WORD_FILE); + create_data_structures(WORD_LISTS_DIRECTORY + '/' + OLD_WORD_FILE, has_checksum); is_old_style_word_list = true; } else { - create_data_structures(WORD_LISTS_DIRECTORY + '/' + LANGUAGES_DIRECTORY + '/' + language); + create_data_structures(WORD_LISTS_DIRECTORY + '/' + LANGUAGES_DIRECTORY + '/' + language, has_checksum); is_old_style_word_list = false; } if (num_words == 0) @@ -181,15 +209,17 @@ namespace crypto boost::split(wlist, words, boost::is_any_of(" ")); // If it is seed with a checksum. - if (wlist.size() == seed_length + 1) + bool has_checksum = (wlist.size() == seed_length + 1); + + if (has_checksum) { // The last word is the checksum. std::string last_word = wlist.back(); wlist.pop_back(); - std::string checksum = wlist[create_checksum_index(boost::algorithm::join(wlist, " "))]; + std::string checksum = wlist[create_checksum_index(wlist)]; - if (checksum != last_word) + if (checksum.substr(0, unique_prefix_length) != last_word.substr(0, unique_prefix_length)) { // Checksum fail return false; @@ -202,8 +232,8 @@ namespace crypto std::vector<std::string>::iterator it; for (it = languages.begin(); it != languages.end(); it++) { - init(*it); - if (word_list_file_match(wlist)) + init(*it, has_checksum); + if (word_list_file_match(wlist, has_checksum)) { break; } @@ -211,8 +241,8 @@ namespace crypto // If no such file was found, see if the old style word list file has them all. if (it == languages.end()) { - init("", true); - if (!word_list_file_match(wlist)) + init("", has_checksum, true); + if (!word_list_file_match(wlist, has_checksum)) { return false; } @@ -227,9 +257,18 @@ namespace crypto uint32_t val; uint32_t w1, w2, w3; - w1 = words_map.at(wlist[i*3]); - w2 = words_map.at(wlist[i*3 + 1]); - w3 = words_map.at(wlist[i*3 + 2]); + if (has_checksum) + { + w1 = words_map.at(wlist[i*3].substr(0, unique_prefix_length)); + w2 = words_map.at(wlist[i*3 + 1].substr(0, unique_prefix_length)); + w3 = words_map.at(wlist[i*3 + 2].substr(0, unique_prefix_length)); + } + else + { + w1 = words_map.at(wlist[i*3]); + w2 = words_map.at(wlist[i*3 + 1]); + w3 = words_map.at(wlist[i*3 + 2]); + } val = w1 + n * (((n - w1) + w2) % n) + n * n * (((n - w2) + w3) % n); @@ -293,7 +332,7 @@ namespace crypto } words.pop_back(); - words += (' ' + words_store[create_checksum_index(words)]); + words += (' ' + words_store[create_checksum_index(words_store)]); return false; } |