#include #include #include #include #include #include #include #include #include #include #include #include "I2PEndian.h" #include "Reseed.h" #include "Log.h" #include "Identity.h" #include "CryptoConst.h" #include "NetDb.h" #include "util.h" namespace i2p { namespace data { static std::vector httpReseedHostList = { // "http://193.150.121.66/netDb/", // unstable // "http://us.reseed.i2p2.no/", // misconfigured, not serving reseed data // "http://jp.reseed.i2p2.no/", // Really outdated RIs "http://netdb.i2p2.no/", // only SU3 (v2) support "http://i2p.mooo.com/netDb/", "http://uk.reseed.i2p2.no/", "http://i2p-netdb.innovatio.no/" }; //TODO: Remember to add custom port support. Not all serves on 443 static std::vector httpsReseedHostList = { // "https://193.150.121.66/netDb/", // unstable // "https://i2p-netdb.innovatio.no/",// Vuln to POODLE "https://netdb.i2p2.no/", // Only SU3 (v2) support "https://reseed.i2p-projekt.de/", // Only HTTPS "https://cowpuncher.drollette.com/netdb/", // Only HTTPS and SU3 (v2) support -- will move to a new location "https://i2p.mooo.com/netDb/", "https://link.mx24.eu/", // Only HTTPS and SU3 (v2) support "https://i2pseed.zarrenspry.info/", // Only HTTPS and SU3 (v2) support "https://ieb9oopo.mooo.com/" // Only HTTPS and SU3 (v2) support }; Reseeder::Reseeder() { } Reseeder::~Reseeder() { } bool Reseeder::reseedNow() { // This method is deprecated try { std::string reseedHost = httpReseedHostList[(rand() % httpReseedHostList.size())]; LogPrint("Reseeding from ", reseedHost); std::string content = i2p::util::http::httpRequest(reseedHost); if (content == "") { LogPrint("Reseed failed"); return false; } boost::regex e("<\\s*A\\s+[^>]*href\\s*=\\s*\"([^\"]*)\"", boost::regex::normal | boost::regbase::icase); boost::sregex_token_iterator i(content.begin(), content.end(), e, 1); boost::sregex_token_iterator j; //TODO: Ugly code, try to clean up. //TODO: Try to reduce N number of variables std::string name; std::string routerInfo; std::string tmpUrl; std::string filename; std::string ignoreFileSuffix = ".su3"; boost::filesystem::path root = i2p::util::filesystem::GetDataDir(); while (i != j) { name = *i++; if (name.find(ignoreFileSuffix)!=std::string::npos) continue; LogPrint("Downloading ", name); tmpUrl = reseedHost; tmpUrl.append(name); routerInfo = i2p::util::http::httpRequest(tmpUrl); if (routerInfo.size()==0) continue; filename = root.string(); #ifndef _WIN32 filename += "/netDb/r"; #else filename += "\\netDb\\r"; #endif filename += name.at(11); // first char in id #ifndef _WIN32 filename.append("/"); #else filename.append("\\"); #endif filename.append(name.c_str()); std::ofstream outfile (filename, std::ios::binary); outfile << routerInfo; outfile.close(); } return true; } catch (std::exception& ex) { //TODO: error reporting return false; } return false; } int Reseeder::ReseedNowSU3 () { CryptoPP::AutoSeededRandomPool rnd; auto ind = rnd.GenerateWord32 (0, httpReseedHostList.size() - 1); std::string reseedHost = httpReseedHostList[ind]; return ReseedFromSU3 (reseedHost); } int Reseeder::ReseedFromSU3 (const std::string& host) { std::string url = host + "i2pseeds.su3"; LogPrint (eLogInfo, "Dowloading SU3 from ", host); std::string su3 = i2p::util::http::httpRequest (url); if (su3.length () > 0) { std::stringstream s(su3); return ProcessSU3Stream (s); } else { LogPrint (eLogWarning, "SU3 download failed"); return 0; } } int Reseeder::ProcessSU3File (const char * filename) { std::ifstream s(filename, std::ifstream::binary); if (s.is_open ()) return ProcessSU3Stream (s); else { LogPrint (eLogError, "Can't open file ", filename); return 0; } } const char SU3_MAGIC_NUMBER[]="I2Psu3"; const uint32_t ZIP_HEADER_SIGNATURE = 0x04034B50; const uint32_t ZIP_CENTRAL_DIRECTORY_HEADER_SIGNATURE = 0x02014B50; const uint16_t ZIP_BIT_FLAG_DATA_DESCRIPTOR = 0x0008; int Reseeder::ProcessSU3Stream (std::istream& s) { char magicNumber[7]; s.read (magicNumber, 7); // magic number and zero byte 6 if (strcmp (magicNumber, SU3_MAGIC_NUMBER)) { LogPrint (eLogError, "Unexpected SU3 magic number"); return 0; } s.seekg (1, std::ios::cur); // su3 file format version SigningKeyType signatureType; s.read ((char *)&signatureType, 2); // signature type signatureType = be16toh (signatureType); uint16_t signatureLength; s.read ((char *)&signatureLength, 2); // signature length signatureLength = be16toh (signatureLength); s.seekg (1, std::ios::cur); // unused uint8_t versionLength; s.read ((char *)&versionLength, 1); // version length s.seekg (1, std::ios::cur); // unused uint8_t signerIDLength; s.read ((char *)&signerIDLength, 1); // signer ID length uint64_t contentLength; s.read ((char *)&contentLength, 8); // content length contentLength = be64toh (contentLength); s.seekg (1, std::ios::cur); // unused uint8_t fileType; s.read ((char *)&fileType, 1); // file type if (fileType != 0x00) // zip file { LogPrint (eLogError, "Can't handle file type ", (int)fileType); return 0; } s.seekg (1, std::ios::cur); // unused uint8_t contentType; s.read ((char *)&contentType, 1); // content type if (contentType != 0x03) // reseed data { LogPrint (eLogError, "Unexpected content type ", (int)contentType); return 0; } s.seekg (12, std::ios::cur); // unused s.seekg (versionLength, std::ios::cur); // skip version char signerID[256]; s.read (signerID, signerIDLength); // signerID signerID[signerIDLength] = 0; //try to verify signature auto it = m_SigningKeys.find (signerID); if (it != m_SigningKeys.end ()) { // TODO: implement all signature types if (signatureType == SIGNING_KEY_TYPE_RSA_SHA512_4096) { size_t pos = s.tellg (); size_t tbsLen = pos + contentLength; uint8_t * tbs = new uint8_t[tbsLen]; s.seekg (0, std::ios::beg); s.read ((char *)tbs, tbsLen); uint8_t * signature = new uint8_t[signatureLength]; s.read ((char *)signature, signatureLength); // RSA-raw i2p::crypto::RSASHA5124096RawVerifier verifier(it->second); verifier.Update (tbs, tbsLen); if (!verifier.Verify (signature)) LogPrint (eLogWarning, "SU3 signature verification failed"); delete[] signature; delete[] tbs; s.seekg (pos, std::ios::beg); } else LogPrint (eLogWarning, "Signature type ", signatureType, " is not supported"); } else LogPrint (eLogWarning, "Certificate for ", signerID, " not loaded"); // handle content int numFiles = 0; size_t contentPos = s.tellg (); while (!s.eof ()) { uint32_t signature; s.read ((char *)&signature, 4); signature = le32toh (signature); if (signature == ZIP_HEADER_SIGNATURE) { // next local file s.seekg (2, std::ios::cur); // version uint16_t bitFlag; s.read ((char *)&bitFlag, 2); bitFlag = le16toh (bitFlag); uint16_t compressionMethod; s.read ((char *)&compressionMethod, 2); compressionMethod = le16toh (compressionMethod); s.seekg (4, std::ios::cur); // skip fields we don't care about uint32_t compressedSize, uncompressedSize; uint8_t crc32[4]; s.read ((char *)crc32, 4); s.read ((char *)&compressedSize, 4); compressedSize = le32toh (compressedSize); s.read ((char *)&uncompressedSize, 4); uncompressedSize = le32toh (uncompressedSize); uint16_t fileNameLength, extraFieldLength; s.read ((char *)&fileNameLength, 2); fileNameLength = le16toh (fileNameLength); s.read ((char *)&extraFieldLength, 2); extraFieldLength = le16toh (extraFieldLength); char localFileName[255]; s.read (localFileName, fileNameLength); localFileName[fileNameLength] = 0; s.seekg (extraFieldLength, std::ios::cur); // take care about data desriptor if presented if (bitFlag & ZIP_BIT_FLAG_DATA_DESCRIPTOR) { size_t pos = s.tellg (); if (!FindZipDataDescriptor (s)) { LogPrint (eLogError, "SU3 archive data descriptor not found"); return numFiles; } s.read ((char *)crc32, 4); s.read ((char *)&compressedSize, 4); compressedSize = le32toh (compressedSize) + 4; // ??? we must consider signature as part of compressed data s.read ((char *)&uncompressedSize, 4); uncompressedSize = le32toh (uncompressedSize); // now we know compressed and uncompressed size s.seekg (pos, std::ios::beg); // back to compressed data } LogPrint (eLogDebug, "Proccessing file ", localFileName, " ", compressedSize, " bytes"); if (!compressedSize) { LogPrint (eLogWarning, "Unexpected size 0. Skipped"); continue; } uint8_t * compressed = new uint8_t[compressedSize]; s.read ((char *)compressed, compressedSize); if (compressionMethod) // we assume Deflate { CryptoPP::Inflator decompressor; decompressor.Put (compressed, compressedSize); decompressor.MessageEnd(); if (decompressor.MaxRetrievable () <= uncompressedSize) { uint8_t * uncompressed = new uint8_t[uncompressedSize]; decompressor.Get (uncompressed, uncompressedSize); if (CryptoPP::CRC32().VerifyDigest (crc32, uncompressed, uncompressedSize)) { i2p::data::netdb.AddRouterInfo (uncompressed, uncompressedSize); numFiles++; } else LogPrint (eLogError, "CRC32 verification failed"); delete[] uncompressed; } else LogPrint (eLogError, "Actual uncompressed size ", decompressor.MaxRetrievable (), " exceed ", uncompressedSize, " from header"); } else // no compression { i2p::data::netdb.AddRouterInfo (compressed, compressedSize); numFiles++; } delete[] compressed; if (bitFlag & ZIP_BIT_FLAG_DATA_DESCRIPTOR) s.seekg (12, std::ios::cur); // skip data descriptor section if presented (12 = 16 - 4) } else { if (signature != ZIP_CENTRAL_DIRECTORY_HEADER_SIGNATURE) LogPrint (eLogWarning, "Missing zip central directory header"); break; // no more files } size_t end = s.tellg (); if (end - contentPos >= contentLength) break; // we are beyond contentLength } return numFiles; } const uint8_t ZIP_DATA_DESCRIPTOR_SIGNATURE[] = { 0x50, 0x4B, 0x07, 0x08 }; bool Reseeder::FindZipDataDescriptor (std::istream& s) { size_t nextInd = 0; while (!s.eof ()) { uint8_t nextByte; s.read ((char *)&nextByte, 1); if (nextByte == ZIP_DATA_DESCRIPTOR_SIGNATURE[nextInd]) { nextInd++; if (nextInd >= sizeof (ZIP_DATA_DESCRIPTOR_SIGNATURE)) return true; } else nextInd = 0; } return false; } const char CERTIFICATE_HEADER[] = "-----BEGIN CERTIFICATE-----"; const char CERTIFICATE_FOOTER[] = "-----END CERTIFICATE-----"; void Reseeder::LoadCertificate (const std::string& filename) { std::ifstream s(filename, std::ifstream::binary); if (s.is_open ()) { s.seekg (0, std::ios::end); size_t len = s.tellg (); s.seekg (0, std::ios::beg); char buf[2048]; s.read (buf, len); std::string cert (buf, len); // assume file in pem format auto pos1 = cert.find (CERTIFICATE_HEADER); auto pos2 = cert.find (CERTIFICATE_FOOTER); if (pos1 == std::string::npos || pos2 == std::string::npos) { LogPrint (eLogError, "Malformed certificate file"); return; } pos1 += strlen (CERTIFICATE_HEADER); pos2 -= pos1; std::string base64 = cert.substr (pos1, pos2); CryptoPP::ByteQueue queue; CryptoPP::Base64Decoder decoder; // regular base64 rather than I2P decoder.Attach (new CryptoPP::Redirector (queue)); decoder.Put ((const uint8_t *)base64.data(), base64.length()); decoder.MessageEnd (); LoadCertificate (queue); } else LogPrint (eLogError, "Can't open certificate file ", filename); } std::string Reseeder::LoadCertificate (CryptoPP::ByteQueue& queue) { // extract X.509 CryptoPP::BERSequenceDecoder x509Cert (queue); CryptoPP::BERSequenceDecoder tbsCert (x509Cert); // version uint32_t ver; CryptoPP::BERGeneralDecoder context (tbsCert, CryptoPP::CONTEXT_SPECIFIC | CryptoPP::CONSTRUCTED); CryptoPP::BERDecodeUnsigned(context, ver, CryptoPP::INTEGER); // serial CryptoPP::Integer serial; serial.BERDecode(tbsCert); // signature CryptoPP::BERSequenceDecoder signature (tbsCert); signature.SkipAll(); // issuer std::string name; CryptoPP::BERSequenceDecoder issuer (tbsCert); { CryptoPP::BERSetDecoder c (issuer); c.SkipAll(); CryptoPP::BERSetDecoder st (issuer); st.SkipAll(); CryptoPP::BERSetDecoder l (issuer); l.SkipAll(); CryptoPP::BERSetDecoder o (issuer); o.SkipAll(); CryptoPP::BERSetDecoder ou (issuer); ou.SkipAll(); CryptoPP::BERSetDecoder cn (issuer); { CryptoPP::BERSequenceDecoder attributes (cn); { CryptoPP::BERGeneralDecoder ident(attributes, CryptoPP::OBJECT_IDENTIFIER); ident.SkipAll (); CryptoPP::BERDecodeTextString (attributes, name, CryptoPP::UTF8_STRING); } } } issuer.SkipAll(); // validity CryptoPP::BERSequenceDecoder validity (tbsCert); validity.SkipAll(); // subject CryptoPP::BERSequenceDecoder subject (tbsCert); subject.SkipAll(); // public key CryptoPP::BERSequenceDecoder publicKey (tbsCert); { CryptoPP::BERSequenceDecoder ident (publicKey); ident.SkipAll (); CryptoPP::BERGeneralDecoder key (publicKey, CryptoPP::BIT_STRING); key.Skip (1); // FIXME: probably bug in crypto++ CryptoPP::BERSequenceDecoder keyPair (key); CryptoPP::Integer n; n.BERDecode (keyPair); if (name.length () > 0) { PublicKey value; n.Encode (value, 512); m_SigningKeys[name] = value; } else LogPrint (eLogWarning, "Unknown issuer. Skipped"); } publicKey.SkipAll(); tbsCert.SkipAll(); x509Cert.SkipAll(); return name; } void Reseeder::LoadCertificates () { boost::filesystem::path reseedDir = i2p::util::filesystem::GetCertificatesDir() / "reseed"; if (!boost::filesystem::exists (reseedDir)) { LogPrint (eLogWarning, "Reseed certificates not loaded. ", reseedDir, " doesn't exist"); return; } int numCertificates = 0; boost::filesystem::directory_iterator end; // empty for (boost::filesystem::directory_iterator it (reseedDir); it != end; ++it) { if (boost::filesystem::is_regular_file (it->status()) && it->path ().extension () == ".crt") { LoadCertificate (it->path ().string ()); numCertificates++; } } LogPrint (eLogInfo, numCertificates, " certificates loaded"); } std::string Reseeder::HttpsRequest (const std::string& address) { i2p::util::http::url u(address); TlsSession session (u.host_, 443); // send request std::stringstream ss; ss << "GET " << u.path_ << " HTTP/1.1\r\nHost: " << u.host_ << "\r\nAccept: */*\r\n" << "User-Agent: Wget/1.11.4\r\n" << "Connection: close\r\n\r\n"; session.Send ((uint8_t *)ss.str ().c_str (), ss.str ().length ()); // read response std::stringstream rs; while (session.Receive (rs)) ; return i2p::util::http::GetHttpContent (rs); } TlsSession::TlsSession (const std::string& host, int port): m_Seqn (0) { m_Site.connect(host, boost::lexical_cast(port)); if (m_Site.good ()) { Handshake (); } else LogPrint (eLogError, "Can't connect to ", host, ":", port); } void TlsSession::Handshake () { static uint8_t clientHello[] = { 0x16, // handshake 0x03, 0x03, // version (TSL 1.2) 0x00, 0x2F, // length of handshake // handshake 0x01, // handshake type (client hello) 0x00, 0x00, 0x2B, // length of handshake payload // client hello 0x03, 0x03, // highest version supported (TSL 1.2) 0x45, 0xFA, 0x01, 0x19, 0x74, 0x55, 0x18, 0x36, 0x42, 0x05, 0xC1, 0xDD, 0x4A, 0x21, 0x80, 0x80, 0xEC, 0x37, 0x11, 0x93, 0x16, 0xF4, 0x66, 0x00, 0x12, 0x67, 0xAB, 0xBA, 0xFF, 0x29, 0x13, 0x9E, // 32 random bytes 0x00, // session id length 0x00, 0x02, // chiper suites length 0x00, 0x3D, // RSA_WITH_AES_256_CBC_SHA256 0x01, // compression methods length 0x00, // no compression 0x00, 0x00 // extensions length }; static uint8_t changeCipherSpecs[] = { 0x14, // change chiper specs 0x03, 0x03, // version (TSL 1.2) 0x00, 0x01, // length 0x01 // type }; static uint8_t finished[] = { 0x16, // handshake 0x03, 0x03, // version (TSL 1.2) 0x00, 0x50, // length of handshake (80 bytes) // handshake (encrypted) // unencrypted context // 0x14 handshake type (finished) // 0x00, 0x00, 0x0C length of handshake payload // 12 bytes of verified data }; // send ClientHello m_Site.write ((char *)clientHello, sizeof (clientHello)); m_FinishedHash.Update (clientHello + 5, sizeof (clientHello) - 5); // read ServerHello uint8_t type; m_Site.read ((char *)&type, 1); uint16_t version; m_Site.read ((char *)&version, 2); uint16_t length; m_Site.read ((char *)&length, 2); length = be16toh (length); char * serverHello = new char[length]; m_Site.read (serverHello, length); m_FinishedHash.Update ((uint8_t *)serverHello, length); uint8_t serverRandom[32]; if (serverHello[0] == 0x02) // handshake type server hello memcpy (serverRandom, serverHello + 6, 32); else LogPrint (eLogError, "Unexpected handshake type ", (int)serverHello[0]); delete[] serverHello; // read Certificate m_Site.read ((char *)&type, 1); m_Site.read ((char *)&version, 2); m_Site.read ((char *)&length, 2); length = be16toh (length); char * certificate = new char[length]; m_Site.read (certificate, length); m_FinishedHash.Update ((uint8_t *)certificate, length); CryptoPP::RSA::PublicKey publicKey; // 0 - handshake type // 1 - 3 - handshake payload length // 4 - 6 - length of array of certificates // 7 - 9 - length of certificate if (certificate[0] == 0x0B) // handshake type certificate publicKey = ExtractPublicKey ((uint8_t *)certificate + 10, length - 10); else LogPrint (eLogError, "Unexpected handshake type ", (int)certificate[0]); delete[] certificate; // read ServerHelloDone m_Site.read ((char *)&type, 1); m_Site.read ((char *)&version, 2); m_Site.read ((char *)&length, 2); length = be16toh (length); char * serverHelloDone = new char[length]; m_Site.read (serverHelloDone, length); m_FinishedHash.Update ((uint8_t *)serverHelloDone, length); if (serverHelloDone[0] != 0x0E) // handshake type hello done LogPrint (eLogError, "Unexpected handshake type ", (int)serverHelloDone[0]); delete[] serverHelloDone; // our turn now // generate secret key uint8_t secret[48]; secret[0] = 3; secret[1] = 3; // version m_Rnd.GenerateBlock (secret + 2, 46); // 46 random bytes // encrypt RSA CryptoPP::RSAES_PKCS1v15_Encryptor encryptor(publicKey); size_t encryptedLen = encryptor.CiphertextLength (48); // number of bytes for encrypted 48 bytes, usually 256 (2048 bits key) uint8_t * encrypted = new uint8_t[encryptedLen + 2]; // + 2 bytes for length htobe16buf (encrypted, encryptedLen); // first two bytes means length encryptor.Encrypt (m_Rnd, secret, 48, encrypted + 2); // send ClientKeyExchange // 0x10 - handshake type "client key exchange" SendHandshakeMsg (0x10, encrypted, encryptedLen + 2); delete[] encrypted; // send ChangeCipherSpecs m_Site.write ((char *)changeCipherSpecs, sizeof (changeCipherSpecs)); // calculate master secret uint8_t masterSecret[48], random[64]; memcpy (random, clientHello + 11, 32); memcpy (random + 32, serverRandom, 32); PRF (secret, "master secret", random, 64, 48, masterSecret); // expand master secret uint8_t keys[256]; // clientMACKey(32), serverMACKey(32), clientKey(32), serverKey(32) memcpy (random, serverRandom, 32); memcpy (random + 32, clientHello + 11, 32); PRF (masterSecret, "key expansion", random, 64, 256, keys); memcpy (m_MacKey, keys, 32); m_Encryption.SetKey (keys + 64); m_Decryption.SetKey (keys + 96); // send finished uint8_t finishedHashDigest[32], finishedPayload[40], encryptedPayload[80]; finishedPayload[0] = 0x14; // handshake type (finished) finishedPayload[1] = 0; finishedPayload[2] = 0; finishedPayload[3] = 0x0C; // 12 bytes m_FinishedHash.Final (finishedHashDigest); PRF (masterSecret, "client finished", finishedHashDigest, 32, 12, finishedPayload + 4); uint8_t mac[32]; CalculateMAC (0x16, finishedPayload, 16, mac); Encrypt (finishedPayload, 16, mac, encryptedPayload); m_Site.write ((char *)finished, sizeof (finished)); m_Site.write ((char *)encryptedPayload, 80); // read ChangeCipherSpecs uint8_t changeCipherSpecs1[6]; m_Site.read ((char *)changeCipherSpecs1, 6); // read finished m_Site.read ((char *)&type, 1); m_Site.read ((char *)&version, 2); m_Site.read ((char *)&length, 2); length = be16toh (length); char * finished1 = new char[length]; m_Site.read (finished1, length); delete[] finished1; } void TlsSession::SendHandshakeMsg (uint8_t handshakeType, uint8_t * data, size_t len) { uint8_t handshakeHeader[9]; handshakeHeader[0] = 0x16; // handshake handshakeHeader[1] = 0x03; handshakeHeader[2] = 0x03; // version is always TLS 1.2 (3,3) htobe16buf (handshakeHeader + 3, len + 4); // length of payload //payload starts handshakeHeader[5] = handshakeType; // handshake type handshakeHeader[6] = 0; // highest byte of payload length is always zero htobe16buf (handshakeHeader + 7, len); // length of data m_Site.write ((char *)handshakeHeader, 9); m_FinishedHash.Update (handshakeHeader + 5, 4); // only payload counts m_Site.write ((char *)data, len); m_FinishedHash.Update (data, len); } void TlsSession::PRF (const uint8_t * secret, const char * label, const uint8_t * random, size_t randomLen, size_t len, uint8_t * buf) { // secret is assumed 48 bytes // random is not more than 64 bytes CryptoPP::HMAC hmac (secret, 48); uint8_t seed[96]; size_t seedLen; seedLen = strlen (label); memcpy (seed, label, seedLen); memcpy (seed + seedLen, random, randomLen); seedLen += randomLen; size_t offset = 0; uint8_t a[128]; hmac.CalculateDigest (a, seed, seedLen); while (offset < len) { memcpy (a + 32, seed, seedLen); hmac.CalculateDigest (buf + offset, a, seedLen + 32); offset += 32; hmac.CalculateDigest (a, a, 32); } } size_t TlsSession::Encrypt (const uint8_t * in, size_t len, const uint8_t * mac, uint8_t * out) { size_t size = 0; m_Rnd.GenerateBlock (out, 16); // iv size += 16; m_Encryption.SetIV (out); memcpy (out + size, in, len); size += len; memcpy (out + size, mac, 32); size += 32; uint8_t paddingSize = len + 1; paddingSize &= 0x0F; // %16 if (paddingSize > 0) paddingSize = 16 - paddingSize; memset (out + size, paddingSize, paddingSize + 1); // paddind and last byte are equal to padding size size += paddingSize + 1; m_Encryption.Encrypt (out + 16, size - 16, out + 16); return size; } size_t TlsSession::Decrypt (uint8_t * buf, size_t len) { m_Decryption.SetIV (buf); m_Decryption.Decrypt (buf + 16, len - 16, buf + 16); return len - 48 - buf[len -1] - 1; // IV(16), mac(32) and padding } void TlsSession::CalculateMAC (uint8_t type, const uint8_t * buf, size_t len, uint8_t * mac) { uint8_t header[13]; // seqn (8) + type (1) + version (2) + length (2) htobe64buf (header, m_Seqn); header[8] = type; header[9] = 3; header[10] = 3; // 3,3 means TLS 1.2 htobe16buf (header + 11, len); CryptoPP::HMAC hmac (m_MacKey, 32); hmac.Update (header, 13); hmac.Update (buf, len); hmac.Final (mac); m_Seqn++; } CryptoPP::RSA::PublicKey TlsSession::ExtractPublicKey (const uint8_t * certificate, size_t len) { CryptoPP::ByteQueue queue; queue.Put (certificate, len); queue.MessageEnd (); // extract X.509 CryptoPP::BERSequenceDecoder x509Cert (queue); CryptoPP::BERSequenceDecoder tbsCert (x509Cert); // version uint32_t ver; CryptoPP::BERGeneralDecoder context (tbsCert, CryptoPP::CONTEXT_SPECIFIC | CryptoPP::CONSTRUCTED); CryptoPP::BERDecodeUnsigned(context, ver, CryptoPP::INTEGER); // serial CryptoPP::Integer serial; serial.BERDecode(tbsCert); // signature CryptoPP::BERSequenceDecoder signature (tbsCert); signature.SkipAll(); // issuer CryptoPP::BERSequenceDecoder issuer (tbsCert); issuer.SkipAll(); // validity CryptoPP::BERSequenceDecoder validity (tbsCert); validity.SkipAll(); // subject CryptoPP::BERSequenceDecoder subject (tbsCert); subject.SkipAll(); // public key CryptoPP::BERSequenceDecoder publicKey (tbsCert); CryptoPP::BERSequenceDecoder ident (publicKey); ident.SkipAll (); CryptoPP::BERGeneralDecoder key (publicKey, CryptoPP::BIT_STRING); key.Skip (1); // FIXME: probably bug in crypto++ CryptoPP::BERSequenceDecoder keyPair (key); CryptoPP::Integer n, e; n.BERDecode (keyPair); e.BERDecode (keyPair); CryptoPP::RSA::PublicKey ret; ret.Initialize (n, e); return ret; } void TlsSession::Send (const uint8_t * buf, size_t len) { uint8_t * out = new uint8_t[len + 64 + 5]; // 64 = 32 mac + 16 iv + upto 16 padding, 5 = header out[0] = 0x17; // application data out[1] = 0x03; out[2] = 0x03; // version uint8_t mac[32]; CalculateMAC (0x17, buf, len, mac); size_t encryptedLen = Encrypt (buf, len, mac, out + 5); htobe16buf (out + 3, encryptedLen); m_Site.write ((char *)out, encryptedLen + 5); delete[] out; } bool TlsSession::Receive (std::ostream& rs) { if (m_Site.eof ()) return false; uint8_t type; uint16_t version, length; m_Site.read ((char *)&type, 1); m_Site.read ((char *)&version, 2); m_Site.read ((char *)&length, 2); length = be16toh (length); uint8_t * buf = new uint8_t[length]; m_Site.read ((char *)buf, length); size_t decryptedLen = Decrypt (buf, length); rs.write ((char *)buf + 16, decryptedLen); delete[] buf; return true; } } }