SctDeserializer

struct {
    Version sct_version;          // 1 byte
    LogID id;                     // 32 bytes
    uint64 timestamp;             // 8 bytes (ms since epoch)
    opaque extensions<0..2^16-1>; // 2-byte length prefix + data
    DigitallySigned signature;    // hash_alg(1) + sig_alg(1) + sig_len(2) + sig
} SignedCertificateTimestamp;