fix: potential XSS vulnerabilities (#7923)

* fix: potential XSS vulnerabilities

* feat: support filter and render for readme.md

* chore: set ReadMeAutoRender to true

* fix attachFileName undefined

---------

Co-authored-by: Andy Hsu <[email protected]>

Author: hshpy

go.mod

@@ -83,6 +83,7 @@ require (
 
 require (
 	github.com/STARRY-S/zip v0.2.1 // indirect
+	github.com/aymerick/douceur v0.2.0 // indirect
 	github.com/blevesearch/go-faiss v1.0.20 // indirect
 	github.com/blevesearch/zapx/v16 v16.1.5 // indirect
 	github.com/bodgit/plumbing v1.3.0 // indirect
@@ -97,6 +98,7 @@ require (
 	github.com/dsnet/compress v0.0.2-0.20230904184137-39efe44ab707 // indirect
 	github.com/erikgeiser/coninput v0.0.0-20211004153227-1c3628e74d0f // indirect
 	github.com/fclairamb/go-log v0.5.0 // indirect
+	github.com/gorilla/css v1.0.1 // indirect
 	github.com/hashicorp/go-cleanhttp v0.5.2 // indirect
 	github.com/hashicorp/golang-lru/v2 v2.0.7 // indirect
 	github.com/hekmon/cunits/v2 v2.1.0 // indirect
@@ -105,11 +107,13 @@ require (
 	github.com/klauspost/pgzip v1.2.6 // indirect
 	github.com/kr/text v0.2.0 // indirect
 	github.com/matoous/go-nanoid/v2 v2.1.0 // indirect
+	github.com/microcosm-cc/bluemonday v1.0.27 
 	github.com/nwaples/rardecode/v2 v2.0.0-beta.4.0.20241112120701-034e449c6e78 // indirect
 	github.com/sorairolake/lzip-go v0.3.5 // indirect
 	github.com/taruti/bytepool v0.0.0-20160310082835-5e3a9ea56543 // indirect
 	github.com/therootcompany/xz v1.0.1 // indirect
 	github.com/ulikunitz/xz v0.5.12 // indirect
+	github.com/yuin/goldmark v1.7.8 
 	go4.org v0.0.0-20230225012048-214862532bf5 // indirect
 )
 

go.sum

@@ -68,6 +68,8 @@ github.com/aymanbagabas/go-osc52/v2 v2.0.1 h1:HwpRHbFMcZLEVr42D4p7XBqjyuxQH5SMiE
 github.com/aymanbagabas/go-osc52/v2 v2.0.1/go.mod h1:uYgXzlJ7ZpABp8OJ+exZzJJhRNQ2ASbcXHWsFqH8hp8=
 github.com/aymanbagabas/go-udiff v0.2.0 h1:TK0fH4MteXUDspT88n8CKzvK0X9O2xu9yQjWpi6yML8=
 github.com/aymanbagabas/go-udiff v0.2.0/go.mod h1:RE4Ex0qsGkTAJoQdQQCA0uG+nAzJO/pI/QwceO5fgrA=
+github.com/aymerick/douceur v0.2.0 h1:Mv+mAeH1Q+n9Fr+oyamOlAkUNPWPlA8PPGR0QAaYuPk=
+github.com/aymerick/douceur v0.2.0/go.mod h1:wlT5vV2O3h55X9m7iVYN0TBM0NH/MmbLnd30/FjWUq4=
 github.com/benbjohnson/clock v1.3.0 h1:ip6w0uFQkncKQ979AypyG0ER7mqUSBdKLOgAle/AT8A=
 github.com/benbjohnson/clock v1.3.0/go.mod h1:J11/hYXuz8f4ySSvYwY0FKfm+ezbsZBKZxNJlLklBHA=
 github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
@@ -303,6 +305,8 @@ github.com/googleapis/gax-go/v2 v2.0.4/go.mod h1:0Wqv26UfaUD9n4G6kQubkQ+KchISgw+
 github.com/googleapis/gax-go/v2 v2.0.5/go.mod h1:DWXyrwAJ9X0FpwwEdw+IPEYBICEFu5mhpdKc/us6bOk=
 github.com/googleapis/gax-go/v2 v2.12.2 h1:mhN09QQW1jEWeMF74zGR81R30z4VJzjZsfkUhuHF+DA=
 github.com/googleapis/gax-go/v2 v2.12.2/go.mod h1:61M8vcyyXR2kqKFxKrfA22jaA8JGF7Dc8App1U3H6jc=
+github.com/gorilla/css v1.0.1 h1:ntNaBIghp6JmvWnxbZKANoLyuXTPZ4cAMlo6RyhlbO8=
+github.com/gorilla/css v1.0.1/go.mod h1:BvnYkspnSzMmwRK+b8/xgNPLiIuNZr6vbZBTPQ2A3b0=
 github.com/gorilla/websocket v1.5.0/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/gorilla/websocket v1.5.3 h1:saDtZ6Pbx/0u+bgYQ3q96pZgCzfhKXGPqt7kZ72aNNg=
 github.com/gorilla/websocket v1.5.3/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
@@ -424,6 +428,8 @@ github.com/meilisearch/meilisearch-go v0.27.2 h1:3G21dJ5i208shnLPDsIEZ0L0Geg/5oe
 github.com/meilisearch/meilisearch-go v0.27.2/go.mod h1:SxuSqDcPBIykjWz1PX+KzsYzArNLSCadQodWs8extS0=
 github.com/mholt/archives v0.1.0 h1:FacgJyrjiuyomTuNA92X5GyRBRZjE43Y/lrzKIlF35Q=
 github.com/mholt/archives v0.1.0/go.mod h1:j/Ire/jm42GN7h90F5kzj6hf6ZFzEH66de+hmjEKu+I=
+github.com/microcosm-cc/bluemonday v1.0.27 h1:MpEUotklkwCSLeH+Qdx1VJgNqLlpY2KXwXFM08ygZfk=
+github.com/microcosm-cc/bluemonday v1.0.27/go.mod h1:jFi9vgW+H7c3V0lb6nR74Ib/DIB5OBs92Dimizgw2cA=
 github.com/minio/sha256-simd v1.0.1 h1:6kaan5IFmwTNynnKKpDHe6FWHohJOHhCPchzK49dzMM=
 github.com/minio/sha256-simd v1.0.1/go.mod h1:Pz6AKMiUdngCLpeTL/RJY1M9rUuPMYujV5xJjtbRSN8=
 github.com/minio/sio v0.4.0 h1:u4SWVEm5lXSqU42ZWawV0D9I5AZ5YMmo2RXpEQ/kRhc=
@@ -613,6 +619,8 @@ github.com/yeka/zip v0.0.0-20231116150916-03d6312748a9/go.mod h1:9BnoKCcgJ/+SLhf
 github.com/yuin/goldmark v1.1.27/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/goldmark v1.2.1/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
+github.com/yuin/goldmark v1.7.8 h1:iERMLn0/QJeHFhxSt3p6PeN9mGnvIKSpG9YYorDMnic=
+github.com/yuin/goldmark v1.7.8/go.mod h1:uzxRWxtg69N339t3louHJ7+O03ezfj6PlliRlaOzY1E=
 github.com/yusufpapurcu/wmi v1.2.4 h1:zFUKzehAFReQwLys1b/iSMl+JQGSCSjtVqQn9bBrPo0=
 github.com/yusufpapurcu/wmi v1.2.4/go.mod h1:SBZ9tNy3G9/m5Oi98Zks0QjeHVDvuK0qfxQmPyzfmi0=
 github.com/zzzhr1990/go-common-entity v0.0.0-20221216044934-fd1c571e3a22 h1:X+lHsNTlbatQ1cErXIbtyrh+3MTWxqQFS+sBP/wpFXo=

internal/bootstrap/data/setting.go

@@ -1,6 +1,8 @@
 package data
 
 import (
+	"strconv"
+
 	"github.com/alist-org/alist/v3/cmd/flags"
 	"github.com/alist-org/alist/v3/internal/conf"
 	"github.com/alist-org/alist/v3/internal/db"
@@ -11,7 +13,6 @@ import (
 	"github.com/alist-org/alist/v3/pkg/utils/random"
 	"github.com/pkg/errors"
 	"gorm.io/gorm"
-	"strconv"
 )
 
 var initialSettingItems []model.SettingItem
@@ -141,6 +142,8 @@ func InitialSettings() []model.SettingItem {
 		{Key: conf.AudioAutoplay, Value: "true", Type: conf.TypeBool, Group: model.PREVIEW},
 		{Key: conf.VideoAutoplay, Value: "true", Type: conf.TypeBool, Group: model.PREVIEW},
 		{Key: conf.PreviewArchivesByDefault, Value: "true", Type: conf.TypeBool, Group: model.PREVIEW},
+		{Key: conf.ReadMeAutoRender, Value: "true", Type: conf.TypeBool, Group: model.PREVIEW},
+		{Key: conf.FilterReadMeScripts, Value: "true", Type: conf.TypeBool, Group: model.PREVIEW},
 		// global settings
 		{Key: conf.HideFiles, Value: "/\\/README.md/i", Type: conf.TypeText, Group: model.GLOBAL},
 		{Key: "package_download", Value: "true", Type: conf.TypeBool, Group: model.GLOBAL},

internal/conf/const.go

@@ -31,7 +31,8 @@ const (
 	AudioAutoplay            = "audio_autoplay"
 	VideoAutoplay            = "video_autoplay"
 	PreviewArchivesByDefault = "preview_archives_by_default"
-
+	ReadMeAutoRender         = "readme_autorender"
+	FilterReadMeScripts      = "filter_readme_scripts"
 	// global
 	HideFiles               = "hide_files"
 	CustomizeHead           = "customize_head"

server/common/proxy.go

@@ -1,23 +1,87 @@
 package common
 
 import (
+	"bytes"
 	"context"
 	"fmt"
 	"io"
 	"net/http"
 	"net/url"
 	"os"
+	"strconv"
 	"strings"
 
+	"github.com/alist-org/alist/v3/internal/conf"
 	"github.com/alist-org/alist/v3/internal/model"
 	"github.com/alist-org/alist/v3/internal/net"
+	"github.com/alist-org/alist/v3/internal/setting"
 	"github.com/alist-org/alist/v3/internal/stream"
 	"github.com/alist-org/alist/v3/pkg/http_range"
 	"github.com/alist-org/alist/v3/pkg/utils"
+	"github.com/microcosm-cc/bluemonday"
 	log "github.com/sirupsen/logrus"
+	"github.com/yuin/goldmark"
 )
 
+func processMarkdown(content []byte) ([]byte, error) {
+	var buf bytes.Buffer
+	if err := goldmark.New().Convert(content, &buf); err != nil {
+		return nil, fmt.Errorf("markdown conversion failed: %w", err)
+	}
+	return bluemonday.UGCPolicy().SanitizeBytes(buf.Bytes()), nil
+}
+
 func Proxy(w http.ResponseWriter, r *http.Request, link *model.Link, file model.Obj) error {
+
+	//优先处理md文件
+	if utils.Ext(file.GetName()) == "md" && setting.GetBool(conf.FilterReadMeScripts) {
+		var markdownContent []byte
+		var err error
+
+		if link.MFile != nil {
+			defer link.MFile.Close()
+			attachHeader(w, file)
+			markdownContent, err = io.ReadAll(link.MFile)
+			if err != nil {
+				return fmt.Errorf("failed to read markdown content: %w", err)
+			}
+
+		} else {
+			header := net.ProcessHeader(r.Header, link.Header)
+			res, err := net.RequestHttp(r.Context(), r.Method, header, link.URL)
+			if err != nil {
+				return err
+			}
+			defer res.Body.Close()
+			for h, v := range res.Header {
+				w.Header()[h] = v
+			}
+			w.WriteHeader(res.StatusCode)
+			if r.Method == http.MethodHead {
+				return nil
+			}
+			markdownContent, err = io.ReadAll(res.Body)
+			if err != nil {
+				return fmt.Errorf("failed to read markdown content: %w", err)
+			}
+
+		}
+
+		safeHTML, err := processMarkdown(markdownContent)
+		if err != nil {
+			return err
+		}
+
+		safeHTMLReader := bytes.NewReader(safeHTML)
+		w.Header().Set("Content-Length", strconv.FormatInt(int64(len(safeHTML)), 10))
+		w.Header().Set("Content-Type", "text/html; charset=utf-8")
+		_, err = utils.CopyWithBuffer(w, safeHTMLReader)
+		if err != nil {
+			return err
+		}
+		return nil
+	}
+
 	if link.MFile != nil {
 		defer link.MFile.Close()
 		attachHeader(w, file)