bool XmlValue::readB64(const char *path, unsigned char *data, int length) const
{
XmlValuePtr value = find(path);
if (!value)
return false;
std::string s = value->text();
s.erase(std::remove_if(s.begin(), s.end(), ::isspace), s.end());
BIO *b64 = BIO_new(BIO_f_base64());
BIO_set_flags(b64, BIO_FLAGS_BASE64_NO_NL);
BIO *bmem = BIO_new_mem_buf((void *)s.c_str(), s.size());
bmem = BIO_push(b64, bmem);
int decodedSize = BIO_read(bmem, data, length);
BIO_free_all(b64);
if (decodedSize != length)
{
LOG(ERROR) << "decoding bytes len " << s.size()
<< ", expecting output len " << length
<< ", got " << decodedSize;
return false;
}
return true;
}
bool XmlValue::read(const char *path, bool *out) const
{
XmlValuePtr value = find(path);
if (!value)
return false;
*out = atoi(value->text().c_str());
return true;
}
bool XmlValue::read(const char *path, std::string *out) const
{
XmlValuePtr value = find(path);
if (!value)
return false;
*out = value->text();
return true;
}
bool XmlValue::read(const char *path, Interface *out) const
{
XmlValuePtr node = find(path);
if (!node)
return false;
int major, minor;
bool ok = node->read("name", out->mutable_name())
&& node->read("major", &major)
&& node->read("minor", &minor);
if (!ok)
return false;
out->set_major(major);
out->set_minor(minor);
return true;
}
// Read a boost::serialization config file using an Xml reader..
bool readV6Config( const char *configFile,
EncfsConfig &cfg, ConfigInfo *info)
{
(void)info;
XmlReader rdr;
if (!rdr.load(configFile))
{
LOG(ERROR) << "Failed to load config file " << configFile;
return false;
}
XmlValuePtr serialization = rdr["boost_serialization"];
XmlValuePtr config = (*serialization)["cfg"];
if (!config) {
config = (*serialization)["config"];
}
if (!config) {
LOG(ERROR) << "Unable to find XML configuration in file " << configFile;
return false;
}
int version;
if (!config->read("version", &version) &&
!config->read("@version", &version)) {
LOG(ERROR) << "Unable to find version in config file";
return false;
}
// version numbering was complicated by boost::archive
if (version == 20 || version >= 20100713)
{
VLOG(1) << "found new serialization format";
cfg.set_revision(version);
} else if (version == 26800)
{
VLOG(1) << "found 20080816 version";
cfg.set_revision(20080816);
} else if (version == 26797)
{
VLOG(1) << "found 20080813";
cfg.set_revision(20080813);
} else if (version < V5Latest)
{
LOG(ERROR) << "Invalid version " << version
<< " - please fix config file";
} else
{
LOG(INFO) << "Boost <= 1.41 compatibility mode";
cfg.set_revision(version);
}
VLOG(1) << "subVersion = " << cfg.revision();
config->read("creator", cfg.mutable_creator());
config->read("cipherAlg", cfg.mutable_cipher());
config->read("nameAlg", cfg.mutable_naming());
//(*config)["keySize"] >> cfg.keySize;
int blockSize, blockMacBytes, blockMacRandBytes;
bool uniqueIv, chainedNameIv, externalIv, allowHoles;
config->read("blockSize", &blockSize);
config->read("uniqueIV", &uniqueIv);
config->read("chainedNameIV", &chainedNameIv);
config->read("externalIVChaining", &externalIv);
config->read("blockMACBytes", &blockMacBytes);
config->read("blockMACRandBytes", &blockMacRandBytes);
config->read("allowHoles", &allowHoles);
cfg.set_block_size(blockSize);
cfg.set_unique_iv(uniqueIv);
cfg.set_chained_iv(chainedNameIv);
cfg.set_external_iv(externalIv);
cfg.set_block_mac_bytes(blockMacBytes);
cfg.set_block_mac_rand_bytes(blockMacRandBytes);
cfg.set_allow_holes(allowHoles);
EncryptedKey *encryptedKey = cfg.mutable_key();
int encodedSize;
config->read("encodedKeySize", &encodedSize);
unsigned char *key = new unsigned char[encodedSize];
config->readB64("encodedKeyData", key, encodedSize);
encryptedKey->set_ciphertext(key, encodedSize);
delete[] key;
int keySize;
config->read("keySize", &keySize);
encryptedKey->set_size(keySize / 8); // save as size in bytes
if(cfg.revision() >= 20080816)
{
int saltLen;
config->read("saltLen", &saltLen);
unsigned char *salt = new unsigned char[saltLen];
config->readB64("saltData", salt, saltLen);
encryptedKey->set_salt(salt, saltLen);
delete[] salt;
int kdfIterations, desiredKDFDuration;
config->read("kdfIterations", &kdfIterations);
config->read("desiredKDFDuration", &desiredKDFDuration);
encryptedKey->set_kdf_iterations(kdfIterations);
encryptedKey->set_kdf_duration(desiredKDFDuration);
} else
{
encryptedKey->clear_salt();
encryptedKey->set_kdf_iterations(16);
encryptedKey->clear_kdf_duration();
}
return true;
}
