fish2018/pansou · warning

密文长度为0

Error message

密文长度为0

What it means

DecryptURL decoded the Base64 successfully but the resulting ciphertext has zero length, so there is nothing to AES-decrypt. This guards against empty plaintext that would otherwise crash CBC decryption; the plugin counts the item as skipped.

Solutions

1. Internal handling: the plugin skips the item; no caller action needed.
2. If frequent, log sample item.URL values and inspect the source data for truncation upstream.
3. Treat empty ciphertext the same as empty input: skip before Base64 decoding.
4. Update the plugin if the site's encoding scheme changed such that legitimate values decode to empty.

Example fix

// before
enc := strings.TrimSpace(item.URL)
decryptedURL, err := DecryptURL(enc)
// after
enc := strings.TrimSpace(item.URL)
if enc == "" || enc == "====" {
    skippedCount++
    continue
}
decryptedURL, err := DecryptURL(enc)

if len(strings.Trim(item.URL, "=")) == 0 { /* skip: decodes to empty ciphertext */ }

decryptedURL, err := DecryptURL(item.URL)
if err != nil {
    skippedCount++
    continue // empty/garbled ciphertext; move to next item
}

When it happens

Trigger: item.URL contained only Base64 padding or decoded to an empty byte slice (e.g. the string "====" or an empty-after-trim value) and DecryptURL is called with it.

Common situations: Degenerate/corrupted records in the sdso search index; upstream truncation of the URL field; over-trimming of the input string before it reaches DecryptURL.

Understand the failure class

Background: "must not be empty", "cannot be empty" — required-field validation errors across open-source libraries — this error's family across 41 libraries.

Related errors

• 加密URL不能为空
• username cannot be empty
• token cannot be empty
• 站点地址不能为空
• 站点地址格式错误

AI-assisted analysis of fish2018/pansou@beaa561337 (2026-09-07). Data as JSON: /api/errors/ceed8a7fab44915b. Report an issue: GitHub.

Appendix: source

Thrown at plugin/sdso/sdso.go:391

}

// DecryptURL 解密SDSO网站返回的加密URL
// 输入: Base64编码的密文
// 输出: 解密后的原始网盘链接
func DecryptURL(encryptedURL string) (string, error) {
	if encryptedURL == "" {
		return "", fmt.Errorf("加密URL不能为空")
	}

	// Base64解码
	ciphertext, err := base64.StdEncoding.DecodeString(encryptedURL)
	if err != nil {
		return "", fmt.Errorf("Base64解码失败: %w", err)
	}

	// 检查密文长度
	if len(ciphertext) == 0 {
		return "", fmt.Errorf("密文长度为0")
	}

	// 检查密文长度是否为16的倍数
	if len(ciphertext)%aes.BlockSize != 0 {
		return "", fmt.Errorf("密文长度不是AES块大小的倍数")
	}

	// 创建AES块加密器
	block, err := aes.NewCipher([]byte(AESKey))
	if err != nil {
		return "", fmt.Errorf("创建AES加密器失败: %w", err)
	}

	// 创建CBC模式解密器
	iv := []byte(AESIV)
	if len(iv) != aes.BlockSize {
		return "", fmt.Errorf("IV长度不正确: 期望%d，实际%d", aes.BlockSize, len(iv))
	}

View on GitHub (pinned to beaa561337)