Commit dce2ba3e authored by jan.koester's avatar jan.koester
Browse files

fixed sni

parent e5246d63

src/ssl.cpp

+36 −12
Original line number Diff line number Diff line
@@ -324,8 +324,14 @@ namespace netplus { 


// Hilfsfunktion zum Parsen von SNI (server_name) Extension aus ClientHello

static bool extractSNIFromClientHello(const std::vector<uint8_t>& ch, std::string& out_hostname) {

    if (ch.size() < 43) return false;  // Minimum size for ClientHello (without type byte)

    if (ch[0] != 0x01) return false;   // Type must be ClientHello

    // ✅ CRITICAL: ch includes handshake type (1 byte) + length (3 bytes) + actual ClientHello payload

    // So the actual ClientHello data starts at offset 4!

    if (ch.size() < 4 + 43) {  // 4 byte header + 43 minimum ClientHello

        return false;

    }

    if (ch[0] != 0x01) {

        return false;  // Type must be ClientHello

    }



    auto readU16 = [&](size_t& p) -> uint16_t {

        if (p + 2 > ch.size()) return 0;
@@ -338,36 +344,52 @@ static bool extractSNIFromClientHello(const std::vector<uint8_t>& ch, std::strin 
        return ch[p++];

    };



    size_t p = 1;  // Skip type (0x01)

    size_t p = 4;  // Skip type (1 byte) + length (3 bytes)



    // legacy_version (2 bytes)

    (void)readU16(p);



    // random (32 bytes)

    if (p + 32 > ch.size()) return false;

    if (p + 32 > ch.size()) {

        return false;

    }

    p += 32;



    // session_id

    uint8_t sidLen = readU8(p);

    if (p + sidLen > ch.size()) return false;

    if (p + sidLen > ch.size()) {

        return false;

    }

    p += sidLen;



    // cipher_suites

    uint16_t csLen = readU16(p);

    if (csLen < 2 || (csLen % 2) != 0) return false;

    if (p + csLen > ch.size()) return false;

    if (csLen < 2 || (csLen % 2) != 0) {

        return false;

    }

    if (p + csLen > ch.size()) {

        return false;

    }

    p += csLen;



    // compression_methods

    uint8_t compLen = readU8(p);

    if (compLen < 1) return false;

    if (p + compLen > ch.size()) return false;

    if (compLen < 1) {

        return false;

    }

    if (p + compLen > ch.size()) {

        return false;

    }

    p += compLen;



    // extensions

    if (p + 2 > ch.size()) return false;

    if (p + 2 > ch.size()) {

        return false;

    }

    uint16_t extLen = readU16(p);

    if (p + extLen > ch.size()) return false;

    if (p + extLen > ch.size()) {

        return false;

    }



    size_t eend = p + extLen;
@@ -376,7 +398,9 @@ static bool extractSNIFromClientHello(const std::vector<uint8_t>& ch, std::strin 
        uint16_t el = (uint16_t(ch[p+2]) << 8) | ch[p+3];

        p += 4;



        if (p + el > eend) return false;

        if (p + el > eend) {

            return false;

        }



        // server_name extension (type 0x0000)

        if (et == 0x0000) {