public:

ClientHelloParser() : state_(kEnded),

onhello_cb_(nullptr),

onend_cb_(nullptr),

cb_arg_(nullptr),

session_size_(0),

session_id_(nullptr),

servername_size_(0),

servername_(nullptr),

ocsp_request_(0),

tls_ticket_size_(0),

tls_ticket_(nullptr) {

Reset();

}

class ClientHello {

public:

inline uint8_t session_size() const { return session_size_; }

inline const uint8_t* session_id() const { return session_id_; }

inline bool has_ticket() const { return has_ticket_; }

inline uint8_t servername_size() const { return servername_size_; }

inline const uint8_t* servername() const { return servername_; }

inline int ocsp_request() const { return ocsp_request_; }

private:

uint8_t session_size_;

const uint8_t* session_id_;

bool has_ticket_;

uint8_t servername_size_;

const uint8_t* servername_;

int ocsp_request_;

friend class ClientHelloParser;

};

typedef void (*OnHelloCb)(void* arg, const ClientHello& hello);

typedef void (*OnEndCb)(void* arg);

void Parse(const uint8_t* data, size_t avail);

inline void Reset();

inline void Start(OnHelloCb onhello_cb, OnEndCb onend_cb, void* onend_arg);

inline void End();

inline bool IsPaused() const;

inline bool IsEnded() const;

private:

static const size_t kMaxTLSFrameLen = 16 * 1024 + 5;

static const size_t kMaxSSLExFrameLen = 32 * 1024;

static const uint8_t kServernameHostname = 0;

static const uint8_t kStatusRequestOCSP = 1;

static const size_t kMinStatusRequestSize = 5;

enum ParseState {

kWaiting,

kTLSHeader,

kPaused,

kEnded

};

enum FrameType {

kChangeCipherSpec = 20,

kAlert = 21,

kHandshake = 22,

kApplicationData = 23,

kOther = 255

};

enum HandshakeType {

kClientHello = 1

};

enum ExtensionType {

kServerName = 0,

kStatusRequest = 5,

kTLSSessionTicket = 35

};

bool ParseRecordHeader(const uint8_t* data, size_t avail);

void ParseHeader(const uint8_t* data, size_t avail);

void ParseExtension(const uint16_t type,

const uint8_t* data,

size_t len);

bool ParseTLSClientHello(const uint8_t* data, size_t avail);

ParseState state_;

OnHelloCb onhello_cb_;

OnEndCb onend_cb_;

void* cb_arg_;

size_t frame_len_;

size_t body_offset_;

size_t extension_offset_;

uint8_t session_size_;

const uint8_t* session_id_;

uint16_t servername_size_;

const uint8_t* servername_;

uint8_t ocsp_request_;

uint16_t tls_ticket_size_;

const uint8_t* tls_ticket_;