mnemonics: support for arbitrary (if multiple of 4 bytes) length data

This commit is contained in:
moneromooo-monero 2017-11-09 10:56:53 +00:00
parent 3dd31d33fa
commit 2d1ccc1b88
No known key found for this signature in database
GPG Key ID: 686F07454D6CEFC3
2 changed files with 80 additions and 19 deletions

View File

@ -236,11 +236,13 @@ namespace crypto
/*! /*!
* \brief Converts seed words to bytes (secret key). * \brief Converts seed words to bytes (secret key).
* \param words String containing the words separated by spaces. * \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. * \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 * \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::string &language_name)
{ {
std::vector<std::string> seed; std::vector<std::string> seed;
@ -248,15 +250,23 @@ namespace crypto
boost::algorithm::trim(words); boost::algorithm::trim(words);
boost::split(seed, words, boost::is_any_of(" "), boost::token_compress_on); boost::split(seed, words, boost::is_any_of(" "), boost::token_compress_on);
// error on non-compliant word list if (len % 4)
if (seed.size() != seed_length/2 && seed.size() != seed_length &&
seed.size() != seed_length + 1)
{
return false; return false;
}
// If it is seed with a checksum. bool has_checksum = true;
bool has_checksum = seed.size() == (seed_length + 1); 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; std::vector<uint32_t> matched_indices;
Language::Base *language; Language::Base *language;
@ -290,20 +300,43 @@ namespace crypto
if (!(val % word_list_length == w1)) return false; 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 (len > 0 && duplicate)
if (seed.size() == seed_length/2)
{ {
memcpy(dst.data+16, dst.data, 16); // if electrum 12-word seed, duplicate const size_t expected = len * 3 / 32;
wlist_copy += ' '; std::string wlist_copy = words;
wlist_copy += words; if (seed.size() == expected/2)
{
dst.append(dst); // if electrum 12-word seed, duplicate
wlist_copy += ' ';
wlist_copy += words;
}
} }
return true; 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. * \brief Converts bytes (secret key) to seed words.
* \param src Secret key * \param src Secret key
@ -311,11 +344,11 @@ namespace crypto
* \param language_name Seed language name * \param language_name Seed language name
* \return true if successful false if not. Unsuccessful if wrong key size. * \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) 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; Language::Base *language;
if (language_name == "English") if (language_name == "English")
@ -376,13 +409,13 @@ namespace crypto
uint32_t word_list_length = word_list.size(); uint32_t word_list_length = word_list.size();
// 8 bytes -> 3 words. 8 digits base 16 -> 3 digits base 1626 // 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 w1, w2, w3;
uint32_t val; uint32_t val;
memcpy(&val, (src.data) + (i * 4), 4); memcpy(&val, src + (i * 4), 4);
w1 = val % word_list_length; w1 = val % word_list_length;
w2 = ((val / word_list_length) + w1) % word_list_length; w2 = ((val / word_list_length) + w1) % word_list_length;
@ -404,6 +437,12 @@ namespace crypto
return true; 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. * \brief Gets a list of seed languages that are supported.
* \param languages The vector is set to the list of languages. * \param languages The vector is set to the list of languages.

View File

@ -61,6 +61,17 @@ namespace crypto
const int seed_length = 24; const int seed_length = 24;
const std::string old_language_name = "EnglishOld"; const std::string old_language_name = "EnglishOld";
/*!
* \brief Converts seed words to bytes (secret key).
* \param words String containing the words separated by spaces.
* \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, std::string& dst, size_t len, bool duplicate,
std::string &language_name);
/*! /*!
* \brief Converts seed words to bytes (secret key). * \brief Converts seed words to bytes (secret key).
* \param words String containing the words separated by spaces. * \param words String containing the words separated by spaces.
@ -71,6 +82,17 @@ namespace crypto
bool words_to_bytes(std::string words, crypto::secret_key& dst, bool words_to_bytes(std::string words, crypto::secret_key& dst,
std::string &language_name); std::string &language_name);
/*!
* \brief Converts bytes to seed words.
* \param src Secret data
* \param len Secret data length in bytes (positive multiples of 4 only)
* \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 char *src, size_t len, std::string& words,
const std::string &language_name);
/*! /*!
* \brief Converts bytes (secret key) to seed words. * \brief Converts bytes (secret key) to seed words.
* \param src Secret key * \param src Secret key