From 72524adf3fd8f8ff616c9ca60ae8215991ef8f2a Mon Sep 17 00:00:00 2001 From: zeripath Date: Mon, 19 Dec 2022 15:51:21 +0000 Subject: [PATCH] Ensure that plain files are rendered correctly even when containing ambiguous characters (#22017) (#22160) Backport #22017 As recognised in #21841 the rendering of plain text files is somewhat incorrect when there are ambiguous characters as the html code is double escaped. In fact there are several more problems here. We have a residual isRenderedHTML which is actually simply escaping the file - not rendering it. This is badly named and gives the wrong impression. There is also unusual behaviour whether the file is called a Readme or not and there is no way to get to the source code if the file is called README. In reality what should happen is different depending on whether the file is being rendered a README at the bottom of the directory view or not. 1. If it is rendered as a README on a directory - it should simply be escaped and rendered as `
` text.
2. If it is rendered as a file then it should be rendered as source
code.

This PR therefore does:
1. Rename IsRenderedHTML to IsPlainText
2. Readme files rendered at the bottom of the directory are rendered
without line numbers
3. Otherwise plain text files are rendered as source code.

Replace #21841

Signed-off-by: Andrew Thornton 
Co-authored-by: Lunny Xiao 
---
 modules/charset/escape.go             | 32 ++++++++++++++++++++++++++-
 routers/web/repo/view.go              | 20 ++++-------------
 templates/repo/settings/lfs_file.tmpl |  6 ++---
 templates/repo/view_file.tmpl         |  6 ++---
 4 files changed, 41 insertions(+), 23 deletions(-)

diff --git a/modules/charset/escape.go b/modules/charset/escape.go
index b264a569f..e60099893 100644
--- a/modules/charset/escape.go
+++ b/modules/charset/escape.go
@@ -9,6 +9,7 @@
 package charset
 
 import (
+	"bufio"
 	"io"
 	"strings"
 
@@ -32,7 +33,7 @@ func EscapeControlHTML(text string, locale translation.Locale, allowed ...rune)
 	return streamer.escaped, sb.String()
 }
 
-// EscapeControlReaders escapes the unicode control sequences in a provider reader and writer in a locale and returns the findings as an EscapeStatus and the escaped []byte
+// EscapeControlReaders escapes the unicode control sequences in a provided reader of HTML content and writer in a locale and returns the findings as an EscapeStatus and the escaped []byte
 func EscapeControlReader(reader io.Reader, writer io.Writer, locale translation.Locale, allowed ...rune) (escaped *EscapeStatus, err error) {
 	outputStream := &HTMLStreamerWriter{Writer: writer}
 	streamer := NewEscapeStreamer(locale, outputStream, allowed...).(*escapeStreamer)
@@ -44,6 +45,35 @@ func EscapeControlReader(reader io.Reader, writer io.Writer, locale translation.
 	return streamer.escaped, err
 }
 
+// EscapeControlStringReader escapes the unicode control sequences in a provided reader of string content and writer in a locale and returns the findings as an EscapeStatus and the escaped []byte
+func EscapeControlStringReader(reader io.Reader, writer io.Writer, locale translation.Locale, allowed ...rune) (escaped *EscapeStatus, err error) {
+	bufRd := bufio.NewReader(reader)
+	outputStream := &HTMLStreamerWriter{Writer: writer}
+	streamer := NewEscapeStreamer(locale, outputStream, allowed...).(*escapeStreamer)
+
+	for {
+		line, rdErr := bufRd.ReadString('\n')
+		if len(line) > 0 {
+			if err := streamer.Text(line); err != nil {
+				streamer.escaped.HasError = true
+				log.Error("Error whilst escaping: %v", err)
+				return streamer.escaped, err
+			}
+		}
+		if rdErr != nil {
+			if rdErr != io.EOF {
+				err = rdErr
+			}
+			break
+		}
+		if err := streamer.SelfClosingTag("br"); err != nil {
+			streamer.escaped.HasError = true
+			return streamer.escaped, err
+		}
+	}
+	return streamer.escaped, err
+}
+
 // EscapeControlString escapes the unicode control sequences in a provided string and returns the findings as an EscapeStatus and the escaped string
 func EscapeControlString(text string, locale translation.Locale, allowed ...rune) (escaped *EscapeStatus, output string) {
 	sb := &strings.Builder{}
diff --git a/routers/web/repo/view.go b/routers/web/repo/view.go
index d35ec48df..293a95726 100644
--- a/routers/web/repo/view.go
+++ b/routers/web/repo/view.go
@@ -10,7 +10,6 @@ import (
 	gocontext "context"
 	"encoding/base64"
 	"fmt"
-	gotemplate "html/template"
 	"io"
 	"net/http"
 	"net/url"
@@ -342,15 +341,13 @@ func renderReadmeFile(ctx *context.Context, readmeFile *namedBlob, readmeTreelin
 		if err != nil {
 			log.Error("Render failed for %s in %-v: %v Falling back to rendering source", readmeFile.name, ctx.Repo.Repository, err)
 			buf := &bytes.Buffer{}
-			ctx.Data["EscapeStatus"], _ = charset.EscapeControlReader(rd, buf, ctx.Locale)
-			ctx.Data["FileContent"] = strings.ReplaceAll(
-				gotemplate.HTMLEscapeString(buf.String()), "\n", `
`,
-			)
+			ctx.Data["EscapeStatus"], _ = charset.EscapeControlStringReader(rd, buf, ctx.Locale)
+			ctx.Data["FileContent"] = buf.String()
 		}
 	} else {
-		ctx.Data["IsRenderedHTML"] = true
+		ctx.Data["IsPlainText"] = true
 		buf := &bytes.Buffer{}
-		ctx.Data["EscapeStatus"], err = charset.EscapeControlReader(rd, &charset.BreakWriter{Writer: buf}, ctx.Locale, charset.RuneNBSP)
+		ctx.Data["EscapeStatus"], err = charset.EscapeControlStringReader(rd, buf, ctx.Locale)
 		if err != nil {
 			log.Error("Read failed: %v", err)
 		}
@@ -522,15 +519,6 @@ func renderFile(ctx *context.Context, entry *git.TreeEntry, treeLink, rawLink st
 			}
 			// to prevent iframe load third-party url
 			ctx.Resp.Header().Add("Content-Security-Policy", "frame-src 'self'")
-		} else if readmeExist && !shouldRenderSource {
-			buf := &bytes.Buffer{}
-			ctx.Data["IsRenderedHTML"] = true
-
-			ctx.Data["EscapeStatus"], _ = charset.EscapeControlReader(rd, buf, ctx.Locale)
-
-			ctx.Data["FileContent"] = strings.ReplaceAll(
-				gotemplate.HTMLEscapeString(buf.String()), "\n", `
`,
-			)
 		} else {
 			buf, _ := io.ReadAll(rd)
 
diff --git a/templates/repo/settings/lfs_file.tmpl b/templates/repo/settings/lfs_file.tmpl
index ce3c39eac..6d20aadde 100644
--- a/templates/repo/settings/lfs_file.tmpl
+++ b/templates/repo/settings/lfs_file.tmpl
@@ -17,11 +17,11 @@
 			
 			

 				{{template "repo/unicode_escape_prompt" dict "EscapeStatus" .EscapeStatus "root" $}}
-				

+				

 					{{if .IsMarkup}}
 						{{if .FileContent}}{{.FileContent | Safe}}{{end}}
-					{{else if .IsRenderedHTML}}
-						
{{if .FileContent}}{{.FileContent | Str2html}}{{end}}

+					{{else if .IsPlainText}}
+						
{{if .FileContent}}{{.FileContent | Safe}}{{end}}

 					{{else if not .IsTextFile}}
 						

 							{{if .IsImageFile}}
diff --git a/templates/repo/view_file.tmpl b/templates/repo/view_file.tmpl
index ed2162a41..14031cec4 100644
--- a/templates/repo/view_file.tmpl
+++ b/templates/repo/view_file.tmpl
@@ -82,11 +82,11 @@
 		{{if not (or .IsMarkup .IsRenderedHTML)}}
 			{{template "repo/unicode_escape_prompt" dict "EscapeStatus" .EscapeStatus "root" $}}
 		{{end}}
-		

+		

 			{{if .IsMarkup}}
 				{{if .FileContent}}{{.FileContent | Safe}}{{end}}
-			{{else if .IsRenderedHTML}}
-				
{{if .FileContent}}{{.FileContent | Str2html}}{{end}}

+			{{else if .IsPlainText}}
+				
{{if .FileContent}}{{.FileContent | Safe}}{{end}}

 			{{else if not .IsTextSource}}
 				

 					{{if .IsImageFile}}