XTLS/Xray-core · error

total padding length must not be larger than 65553

Error message

total padding length must not be larger than 65553

What it means

Error "total padding length must not be larger than 65553" thrown in XTLS/Xray-core.

Source

Thrown at proxy/vless/encryption/common.go:254

		}
		if y[1], err = strconv.Atoi(x[1]); err != nil {
			return
		}
		if y[2], err = strconv.Atoi(x[2]); err != nil {
			return
		}
		if i == 0 && (y[0] < 100 || y[1] < 18+17 || y[2] < 18+17) {
			return errors.New("first padding length must not be smaller than 35")
		}
		if i%2 == 0 {
			*paddingLens = append(*paddingLens, y)
			maxLen += max(y[1], y[2])
		} else {
			*paddingGaps = append(*paddingGaps, y)
		}
	}
	if maxLen > 18+65535 {
		return errors.New("total padding length must not be larger than 65553")
	}
	return
}

func CreatPadding(paddingLens, paddingGaps [][3]int) (length int, lens []int, gaps []time.Duration) {
	if len(paddingLens) == 0 {
		paddingLens = [][3]int{{100, 111, 1111}, {50, 0, 3333}}
		paddingGaps = [][3]int{{75, 0, 111}}
	}
	for _, y := range paddingLens {
		l := 0
		if y[0] >= int(crypto.RandBetween(0, 100)) {
			l = int(crypto.RandBetween(int64(y[1]), int64(y[2])))
		}
		lens = append(lens, l)
		length += l
	}
	for _, y := range paddingGaps {

View on GitHub (pinned to 7d214f8b09)

When it happens

Trigger: Thrown at proxy/vless/encryption/common.go:254 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of XTLS/Xray-core@7d214f8b09 (2026-08-15). Data as JSON: /api/errors/d2a32d385212fa2b. Report an issue: GitHub.