mirror of
https://gitee.com/samwaf/SamWaf.git
synced 2025-12-06 14:59:18 +08:00
288 lines
8.9 KiB
Go
288 lines
8.9 KiB
Go
package wafenginecore
|
||
|
||
import (
|
||
"SamWaf/common/zlog"
|
||
"SamWaf/utils"
|
||
"bufio"
|
||
"bytes"
|
||
"compress/flate"
|
||
"compress/gzip"
|
||
"errors"
|
||
"fmt"
|
||
"github.com/andybalholm/brotli"
|
||
"golang.org/x/net/html/charset"
|
||
"golang.org/x/text/encoding"
|
||
"golang.org/x/text/encoding/simplifiedchinese"
|
||
"golang.org/x/text/encoding/unicode"
|
||
"golang.org/x/text/transform"
|
||
"io"
|
||
"net/http"
|
||
"strings"
|
||
)
|
||
|
||
// 返回内容前依据情况进行返回压缩数据
|
||
func (waf *WafEngine) compressContent(res *http.Response, isStaticAssist bool, inputBytes []byte, encodeType string) (respBytes []byte, err error) {
|
||
|
||
// 如果是静态资源响应或资源类型请求，直接返回原始内容
|
||
if isStaticAssist {
|
||
return inputBytes, errors.New("静态资源或资源类型请求，跳过编码转换")
|
||
}
|
||
|
||
// 首先检查Content-Type头中是否明确指定了字符集
|
||
contentType := res.Header.Get("Content-Type")
|
||
var encodedBytes []byte = inputBytes
|
||
charsetName := encodeType
|
||
|
||
// 如果Content-Type中指定了字符集，需要将UTF-8编码的内容转换回原始编码
|
||
if charsetName == "" && strings.Contains(contentType, "charset=") {
|
||
|
||
parts := strings.Split(contentType, ";")
|
||
for _, part := range parts {
|
||
part = strings.TrimSpace(part)
|
||
if strings.HasPrefix(part, "charset=") {
|
||
charsetName = strings.TrimPrefix(part, "charset=")
|
||
charsetName = strings.Trim(charsetName, `"'`)
|
||
break
|
||
}
|
||
}
|
||
}
|
||
// 根据字符集进行编码转换
|
||
if charsetName != "" && !strings.EqualFold(charsetName, "utf-8") && !strings.EqualFold(charsetName, "utf8") {
|
||
switch strings.ToLower(charsetName) {
|
||
case "gbk", "gb2312":
|
||
// 将UTF-8转换为GBK
|
||
encoder := simplifiedchinese.GBK.NewEncoder()
|
||
encodedBytes, err = encoder.Bytes(inputBytes)
|
||
if err != nil {
|
||
zlog.Warn("编码转换失败(UTF-8 -> GBK): %v", err)
|
||
// 转换失败时使用原始UTF-8内容
|
||
encodedBytes = inputBytes
|
||
}
|
||
// 可以根据需要添加其他编码的支持
|
||
default:
|
||
zlog.Debug("不支持的字符集编码转换: %s，保持UTF-8编码", charsetName)
|
||
}
|
||
}
|
||
|
||
// 根据Content-Encoding进行压缩
|
||
switch res.Header.Get("Content-Encoding") {
|
||
case "gzip":
|
||
respBytes, err = utils.GZipEncode(encodedBytes)
|
||
case "deflate":
|
||
respBytes, err = utils.DeflateEncode(encodedBytes)
|
||
case "br":
|
||
respBytes, err = utils.BrotliEncode(encodedBytes)
|
||
default:
|
||
respBytes = encodedBytes
|
||
}
|
||
return
|
||
}
|
||
|
||
// 获取原始内容
|
||
func (waf *WafEngine) getOrgContent(resp *http.Response, isStaticAssist bool, defaultEncoding string) (cntBytes []byte, encodeType string, err error) {
|
||
bodyBytes, err := io.ReadAll(resp.Body)
|
||
if err != nil {
|
||
return bodyBytes, "", fmt.Errorf("读取原始响应体失败: %v", err)
|
||
}
|
||
charsetNameFinal := ""
|
||
// 重新设置响应体，以便后续处理
|
||
resp.Body = io.NopCloser(bytes.NewBuffer(bodyBytes))
|
||
|
||
// 如果是静态资源响应或资源类型请求，直接返回原始内容
|
||
if isStaticAssist {
|
||
return bodyBytes, "", errors.New("静态资源或资源类型请求，跳过编码转换")
|
||
}
|
||
|
||
// 根据内容编码处理压缩
|
||
var bodyReader io.Reader
|
||
switch resp.Header.Get("Content-Encoding") {
|
||
case "gzip":
|
||
gzipReader, gzipErr := gzip.NewReader(resp.Body)
|
||
if gzipErr != nil {
|
||
zlog.Warn("gzip解压失败: %v", gzipErr)
|
||
// 失败时返回错误
|
||
return bodyBytes, "", fmt.Errorf("gzip解压失败: %v", gzipErr)
|
||
}
|
||
bodyReader = gzipReader
|
||
defer gzipReader.Close()
|
||
case "deflate":
|
||
deflateReader := flate.NewReader(resp.Body)
|
||
bodyReader = deflateReader
|
||
defer deflateReader.Close()
|
||
case "br":
|
||
brotliReader := brotli.NewReader(resp.Body)
|
||
bodyReader = brotliReader
|
||
default:
|
||
bodyReader = resp.Body
|
||
}
|
||
// 创建缓冲读取器
|
||
bufReader := bufio.NewReader(bodyReader)
|
||
|
||
// 首先检查Content-Type头中是否明确指定了字符集
|
||
contentType := resp.Header.Get("Content-Type")
|
||
var currentEncoding encoding.Encoding
|
||
|
||
if defaultEncoding != "" {
|
||
switch strings.ToLower(defaultEncoding) {
|
||
case "utf-8", "utf8":
|
||
currentEncoding = unicode.UTF8
|
||
charsetNameFinal = "utf-8"
|
||
break
|
||
case "gbk", "gb2312":
|
||
currentEncoding = simplifiedchinese.GBK
|
||
charsetNameFinal = "gbk"
|
||
break
|
||
default:
|
||
}
|
||
} else if strings.Contains(contentType, "charset=") {
|
||
charsetName := ""
|
||
parts := strings.Split(contentType, ";")
|
||
for _, part := range parts {
|
||
part = strings.TrimSpace(part)
|
||
if strings.HasPrefix(part, "charset=") {
|
||
charsetName = strings.TrimPrefix(part, "charset=")
|
||
charsetName = strings.Trim(charsetName, `"'`)
|
||
break
|
||
}
|
||
}
|
||
|
||
// 如果找到了字符集
|
||
if charsetName != "" {
|
||
zlog.Debug("从Content-Type中检测到字符集: %s", charsetName)
|
||
switch strings.ToLower(charsetName) {
|
||
case "utf-8", "utf8":
|
||
currentEncoding = unicode.UTF8
|
||
charsetNameFinal = "utf-8"
|
||
break
|
||
case "gbk", "gb2312":
|
||
currentEncoding = simplifiedchinese.GBK
|
||
charsetNameFinal = "gbk"
|
||
break
|
||
default:
|
||
currentEncoding = nil // 使用自动检测
|
||
}
|
||
}
|
||
}
|
||
|
||
// 如果没有从Content-Type中获取到编码或获取的编码不支持，则使用自动检测
|
||
if currentEncoding == nil {
|
||
// 增加检测字节数到1024，提高准确性
|
||
peekBytes, peekErr := bufReader.Peek(1024)
|
||
if peekErr != nil && peekErr != io.EOF {
|
||
return bodyBytes, "", errors.New(fmt.Sprintf("编码检测错误，Peek失败: %v", peekErr))
|
||
} else {
|
||
// 先尝试用系统自带的自动检测
|
||
detectedEncoding, name, certain := charset.DetermineEncoding(peekBytes, contentType)
|
||
|
||
if !certain {
|
||
// 自动检测不确定时，尝试从HTML头部meta标签或DOCTYPE中提取编码
|
||
htmlHead := string(peekBytes)
|
||
metaCharset := ""
|
||
// 1. 检查meta标签
|
||
metaIdx := strings.Index(strings.ToLower(htmlHead), "charset=")
|
||
if metaIdx != -1 {
|
||
// 提取charset=后面的内容
|
||
substr := htmlHead[metaIdx+8:]
|
||
// 只取等号后面第一个非字母数字下划线的内容
|
||
for i, c := range substr {
|
||
if !(c == '-' || c == '_' || (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9')) {
|
||
metaCharset = substr[:i]
|
||
break
|
||
}
|
||
}
|
||
if metaCharset == "" {
|
||
metaCharset = substr
|
||
}
|
||
metaCharset = strings.Trim(metaCharset, "\"' />")
|
||
}
|
||
// 2. 检查DOCTYPE声明
|
||
if metaCharset == "" && strings.Contains(htmlHead, "xhtml1-transitional.dtd") {
|
||
// XHTML 1.0 通常默认utf-8或iso-8859-1
|
||
metaCharset = "utf-8"
|
||
}
|
||
if metaCharset != "" {
|
||
zlog.Debug("通过HTML头部meta/doctype辅助检测到字符集: %s", metaCharset)
|
||
switch strings.ToLower(metaCharset) {
|
||
case "utf-8", "utf8":
|
||
currentEncoding = unicode.UTF8
|
||
charsetNameFinal = "utf-8"
|
||
break
|
||
case "gbk", "gb2312":
|
||
currentEncoding = simplifiedchinese.GBK
|
||
charsetNameFinal = "gbk"
|
||
break
|
||
default:
|
||
zlog.Debug("meta标签检测到未知字符集: %s，保持UTF-8", metaCharset)
|
||
return bodyBytes, "", errors.New(fmt.Sprintf("编码检测不确定，且未能从HTML头部meta/doctype提取到编码"))
|
||
}
|
||
} else {
|
||
return bodyBytes, "", errors.New(fmt.Sprintf("编码检测不确定，且未能从HTML头部meta/doctype提取到编码"))
|
||
}
|
||
} else {
|
||
zlog.Debug("编码检测确定为: %s", name)
|
||
currentEncoding = detectedEncoding
|
||
}
|
||
}
|
||
}
|
||
|
||
// 使用检测到的编码创建转换读取器
|
||
reader := transform.NewReader(bufReader, currentEncoding.NewDecoder())
|
||
|
||
// 读取全部内容
|
||
resBodyBytes, readErr := io.ReadAll(reader)
|
||
if readErr != nil {
|
||
zlog.Warn("读取响应体失败: %v", readErr)
|
||
return bodyBytes, "", fmt.Errorf("读取响应体失败: %v", readErr)
|
||
}
|
||
|
||
return resBodyBytes, charsetNameFinal, nil
|
||
}
|
||
|
||
// 处理请求的Content-Encoding解压
|
||
func (waf *WafEngine) decompressRequestContent(req *http.Request) ([]byte, error) {
|
||
if req.Body == nil || req.Body == http.NoBody {
|
||
return nil, nil
|
||
}
|
||
|
||
// 读取原始请求体
|
||
bodyBytes, err := io.ReadAll(req.Body)
|
||
if err != nil {
|
||
return nil, fmt.Errorf("读取请求体失败: %v", err)
|
||
}
|
||
|
||
// 重新设置请求体
|
||
req.Body = io.NopCloser(bytes.NewBuffer(bodyBytes))
|
||
|
||
// 根据Content-Encoding进行解压
|
||
var bodyReader io.Reader
|
||
switch req.Header.Get("Content-Encoding") {
|
||
case "gzip":
|
||
gzipReader, gzipErr := gzip.NewReader(bytes.NewReader(bodyBytes))
|
||
if gzipErr != nil {
|
||
zlog.Warn("请求gzip解压失败: %v", gzipErr)
|
||
return bodyBytes, fmt.Errorf("请求gzip解压失败: %v", gzipErr)
|
||
}
|
||
bodyReader = gzipReader
|
||
defer gzipReader.Close()
|
||
case "deflate":
|
||
deflateReader := flate.NewReader(bytes.NewReader(bodyBytes))
|
||
bodyReader = deflateReader
|
||
defer deflateReader.Close()
|
||
case "br":
|
||
brotliReader := brotli.NewReader(bytes.NewReader(bodyBytes))
|
||
bodyReader = brotliReader
|
||
default:
|
||
// 没有压缩或不支持的压缩格式，直接返回原始内容
|
||
return bodyBytes, nil
|
||
}
|
||
|
||
// 读取解压后的内容
|
||
decompressedBytes, readErr := io.ReadAll(bodyReader)
|
||
if readErr != nil {
|
||
zlog.Warn("读取解压后的请求体失败: %v", readErr)
|
||
return bodyBytes, fmt.Errorf("读取解压后的请求体失败: %v", readErr)
|
||
}
|
||
|
||
return decompressedBytes, nil
|
||
}
|