module websocket import rand import crypto.sha1 import encoding.base64 // htonl64 converts payload lenght to header bits fn htonl64(payload_len u64) []byte { mut ret := []byte{len: 8} ret[0] = byte(((payload_len & (u64(0xff) << 56)) >> 56) & 0xff) ret[1] = byte(((payload_len & (u64(0xff) << 48)) >> 48) & 0xff) ret[2] = byte(((payload_len & (u64(0xff) << 40)) >> 40) & 0xff) ret[3] = byte(((payload_len & (u64(0xff) << 32)) >> 32) & 0xff) ret[4] = byte(((payload_len & (u64(0xff) << 24)) >> 24) & 0xff) ret[5] = byte(((payload_len & (u64(0xff) << 16)) >> 16) & 0xff) ret[6] = byte(((payload_len & (u64(0xff) << 8)) >> 8) & 0xff) ret[7] = byte(((payload_len & (u64(0xff) << 0)) >> 0) & 0xff) return ret } // create_masking_key returs a new masking key byte array fn create_masking_key() []byte { mask_bit := byte(rand.intn(255)) buf := []byte{len: 4, init: `0`} unsafe {C.memcpy(buf.data, &mask_bit, 4)} return buf } // create_key_challenge_response creates a key challange response from security key fn create_key_challenge_response(seckey string) ?string { if seckey.len == 0 { return error('unexpected seckey lengt zero') } guid := '258EAFA5-E914-47DA-95CA-C5AB0DC85B11' sha1buf := seckey + guid shabytes := sha1buf.bytes() hash := sha1.sum(shabytes) b64 := base64.encode(tos(hash.data, hash.len)) unsafe { hash.free() shabytes.free() } return b64 } // get_nonce, returns a randomized array used in handshake process fn get_nonce(nonce_size int) string { mut nonce := []byte{len: nonce_size, cap: nonce_size} alphanum := '0123456789ABCDEFGHIJKLMNOPQRSTUVXYZabcdefghijklmnopqrstuvwxyz' for i in 0 .. nonce_size { nonce[i] = alphanum[rand.intn(alphanum.len)] } return tos(nonce.data, nonce.len).clone() }