diff options
Diffstat (limited to 'src/mnemonics/electrum-words.cpp')
| -rw-r--r-- | src/mnemonics/electrum-words.cpp | 77 |
1 files changed, 58 insertions, 19 deletions
diff --git a/src/mnemonics/electrum-words.cpp b/src/mnemonics/electrum-words.cpp index 6ae33a743..1b14905f6 100644 --- a/src/mnemonics/electrum-words.cpp +++ b/src/mnemonics/electrum-words.cpp @@ -236,11 +236,13 @@ namespace crypto /*! * \brief Converts seed words to bytes (secret key). * \param words String containing the words separated by spaces. - * \param dst To put the secret key restored from the words. + * \param dst To put the secret data restored from the words. + * \param len The number of bytes to expect, 0 if unknown + * \param duplicate If true and len is not zero, we accept half the data, and duplicate it * \param language_name Language of the seed as found gets written here. * \return false if not a multiple of 3 words, or if word is not in the words list */ - bool words_to_bytes(std::string words, crypto::secret_key& dst, + bool words_to_bytes(std::string words, std::string& dst, size_t len, bool duplicate, std::string &language_name) { std::vector<std::string> seed; @@ -248,15 +250,23 @@ namespace crypto boost::algorithm::trim(words); boost::split(seed, words, boost::is_any_of(" "), boost::token_compress_on); - // error on non-compliant word list - if (seed.size() != seed_length/2 && seed.size() != seed_length && - seed.size() != seed_length + 1) - { + if (len % 4) return false; - } - // If it is seed with a checksum. - bool has_checksum = seed.size() == (seed_length + 1); + bool has_checksum = true; + if (len) + { + // error on non-compliant word list + const size_t expected = len * 8 * 3 / 32; + if (seed.size() != expected/2 && seed.size() != expected && + seed.size() != expected + 1) + { + return false; + } + + // If it is seed with a checksum. + has_checksum = seed.size() == (expected + 1); + } std::vector<uint32_t> matched_indices; Language::Base *language; @@ -290,32 +300,55 @@ namespace crypto if (!(val % word_list_length == w1)) return false; - memcpy(dst.data + i * 4, &val, 4); // copy 4 bytes to position + dst.append((const char*)&val, 4); // copy 4 bytes to position } - std::string wlist_copy = words; - if (seed.size() == seed_length/2) + if (len > 0 && duplicate) { - memcpy(dst.data+16, dst.data, 16); // if electrum 12-word seed, duplicate - wlist_copy += ' '; - wlist_copy += words; + const size_t expected = len * 3 / 32; + std::string wlist_copy = words; + if (seed.size() == expected/2) + { + dst.append(dst); // if electrum 12-word seed, duplicate + wlist_copy += ' '; + wlist_copy += words; + } } return true; } /*! + * \brief Converts seed words to bytes (secret key). + * \param words String containing the words separated by spaces. + * \param dst To put the secret key restored from the words. + * \param language_name Language of the seed as found gets written here. + * \return false if not a multiple of 3 words, or if word is not in the words list + */ + bool words_to_bytes(std::string words, crypto::secret_key& dst, + std::string &language_name) + { + std::string s; + if (!words_to_bytes(words, s, sizeof(dst), true, language_name)) + return false; + if (s.size() != sizeof(dst)) + return false; + dst = *(const crypto::secret_key*)s.data(); + return true; + } + + /*! * \brief Converts bytes (secret key) to seed words. * \param src Secret key * \param words Space delimited concatenated words get written here. * \param language_name Seed language name * \return true if successful false if not. Unsuccessful if wrong key size. */ - bool bytes_to_words(const crypto::secret_key& src, std::string& words, + bool bytes_to_words(const char *src, size_t len, std::string& words, const std::string &language_name) { - if (sizeof(src.data) % 4 != 0 || sizeof(src.data) == 0) return false; + if (len % 4 != 0 || len == 0) return false; Language::Base *language; if (language_name == "English") @@ -376,13 +409,13 @@ namespace crypto uint32_t word_list_length = word_list.size(); // 8 bytes -> 3 words. 8 digits base 16 -> 3 digits base 1626 - for (unsigned int i=0; i < sizeof(src.data)/4; i++, words += ' ') + for (unsigned int i=0; i < len/4; i++, words += ' ') { uint32_t w1, w2, w3; uint32_t val; - memcpy(&val, (src.data) + (i * 4), 4); + memcpy(&val, src + (i * 4), 4); w1 = val % word_list_length; w2 = ((val / word_list_length) + w1) % word_list_length; @@ -404,6 +437,12 @@ namespace crypto return true; } + bool bytes_to_words(const crypto::secret_key& src, std::string& words, + const std::string &language_name) + { + return bytes_to_words(src.data, sizeof(src), words, language_name); + } + /*! * \brief Gets a list of seed languages that are supported. * \param languages The vector is set to the list of languages. |