blob: 5036f2890bd46572c1f9dcc35c80186d0362aa50 [file] [log] [blame]
From 6fc21505614f36178df0dad7034b6b8e3f7588d5 Mon Sep 17 00:00:00 2001
From: empijei <robclap8@gmail.com>
Date: Fri, 27 Mar 2020 19:27:55 +0100
Subject: [PATCH 2/3] html/template,text/template: switch to Unicode escapes
for JSON compatibility
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
The existing implementation is not compatible with JSON
escape as it uses hex escaping.
Unicode escape, instead, is valid for both JSON and JS.
This fix avoids creating a separate escaping context for
scripts of type "application/ld+json" and it is more
future-proof in case more JSON+JS contexts get added
to the platform (e.g. import maps).
Fixes #33671
Fixes #37634
Change-Id: Id6f6524b4abc52e81d9d744d46bbe5bf2e081543
Reviewed-on: https://go-review.googlesource.com/c/go/+/226097
Reviewed-by: Carl Johnson <me@carlmjohnson.net>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Dependency Patch #2
Upstream-Status: Backport from https://github.com/golang/go/commit/d4d298040d072ddacea0e0d6b55fb148fff18070
CVE: CVE-2023-24538
Signed-off-by: Shubham Kulkarni <skulkarni@mvista.com>
---
src/html/template/js.go | 70 +++++++++++++++++++++++++++-------------------
src/text/template/funcs.go | 8 +++---
2 files changed, 46 insertions(+), 32 deletions(-)
diff --git a/src/html/template/js.go b/src/html/template/js.go
index 0e91458..ea9c183 100644
--- a/src/html/template/js.go
+++ b/src/html/template/js.go
@@ -163,7 +163,6 @@ func jsValEscaper(args ...interface{}) string {
}
// TODO: detect cycles before calling Marshal which loops infinitely on
// cyclic data. This may be an unacceptable DoS risk.
-
b, err := json.Marshal(a)
if err != nil {
// Put a space before comment so that if it is flush against
@@ -178,8 +177,8 @@ func jsValEscaper(args ...interface{}) string {
// TODO: maybe post-process output to prevent it from containing
// "<!--", "-->", "<![CDATA[", "]]>", or "</script"
// in case custom marshalers produce output containing those.
-
- // TODO: Maybe abbreviate \u00ab to \xab to produce more compact output.
+ // Note: Do not use \x escaping to save bytes because it is not JSON compatible and this escaper
+ // supports ld+json content-type.
if len(b) == 0 {
// In, `x=y/{{.}}*z` a json.Marshaler that produces "" should
// not cause the output `x=y/*z`.
@@ -260,6 +259,8 @@ func replace(s string, replacementTable []string) string {
r, w = utf8.DecodeRuneInString(s[i:])
var repl string
switch {
+ case int(r) < len(lowUnicodeReplacementTable):
+ repl = lowUnicodeReplacementTable[r]
case int(r) < len(replacementTable) && replacementTable[r] != "":
repl = replacementTable[r]
case r == '\u2028':
@@ -283,67 +284,80 @@ func replace(s string, replacementTable []string) string {
return b.String()
}
+var lowUnicodeReplacementTable = []string{
+ 0: `\u0000`, 1: `\u0001`, 2: `\u0002`, 3: `\u0003`, 4: `\u0004`, 5: `\u0005`, 6: `\u0006`,
+ '\a': `\u0007`,
+ '\b': `\u0008`,
+ '\t': `\t`,
+ '\n': `\n`,
+ '\v': `\u000b`, // "\v" == "v" on IE 6.
+ '\f': `\f`,
+ '\r': `\r`,
+ 0xe: `\u000e`, 0xf: `\u000f`, 0x10: `\u0010`, 0x11: `\u0011`, 0x12: `\u0012`, 0x13: `\u0013`,
+ 0x14: `\u0014`, 0x15: `\u0015`, 0x16: `\u0016`, 0x17: `\u0017`, 0x18: `\u0018`, 0x19: `\u0019`,
+ 0x1a: `\u001a`, 0x1b: `\u001b`, 0x1c: `\u001c`, 0x1d: `\u001d`, 0x1e: `\u001e`, 0x1f: `\u001f`,
+}
+
var jsStrReplacementTable = []string{
- 0: `\0`,
+ 0: `\u0000`,
'\t': `\t`,
'\n': `\n`,
- '\v': `\x0b`, // "\v" == "v" on IE 6.
+ '\v': `\u000b`, // "\v" == "v" on IE 6.
'\f': `\f`,
'\r': `\r`,
// Encode HTML specials as hex so the output can be embedded
// in HTML attributes without further encoding.
- '"': `\x22`,
- '&': `\x26`,
- '\'': `\x27`,
- '+': `\x2b`,
+ '"': `\u0022`,
+ '&': `\u0026`,
+ '\'': `\u0027`,
+ '+': `\u002b`,
'/': `\/`,
- '<': `\x3c`,
- '>': `\x3e`,
+ '<': `\u003c`,
+ '>': `\u003e`,
'\\': `\\`,
}
// jsStrNormReplacementTable is like jsStrReplacementTable but does not
// overencode existing escapes since this table has no entry for `\`.
var jsStrNormReplacementTable = []string{
- 0: `\0`,
+ 0: `\u0000`,
'\t': `\t`,
'\n': `\n`,
- '\v': `\x0b`, // "\v" == "v" on IE 6.
+ '\v': `\u000b`, // "\v" == "v" on IE 6.
'\f': `\f`,
'\r': `\r`,
// Encode HTML specials as hex so the output can be embedded
// in HTML attributes without further encoding.
- '"': `\x22`,
- '&': `\x26`,
- '\'': `\x27`,
- '+': `\x2b`,
+ '"': `\u0022`,
+ '&': `\u0026`,
+ '\'': `\u0027`,
+ '+': `\u002b`,
'/': `\/`,
- '<': `\x3c`,
- '>': `\x3e`,
+ '<': `\u003c`,
+ '>': `\u003e`,
}
-
var jsRegexpReplacementTable = []string{
- 0: `\0`,
+ 0: `\u0000`,
'\t': `\t`,
'\n': `\n`,
- '\v': `\x0b`, // "\v" == "v" on IE 6.
+ '\v': `\u000b`, // "\v" == "v" on IE 6.
'\f': `\f`,
'\r': `\r`,
// Encode HTML specials as hex so the output can be embedded
// in HTML attributes without further encoding.
- '"': `\x22`,
+ '"': `\u0022`,
'$': `\$`,
- '&': `\x26`,
- '\'': `\x27`,
+ '&': `\u0026`,
+ '\'': `\u0027`,
'(': `\(`,
')': `\)`,
'*': `\*`,
- '+': `\x2b`,
+ '+': `\u002b`,
'-': `\-`,
'.': `\.`,
'/': `\/`,
- '<': `\x3c`,
- '>': `\x3e`,
+ '<': `\u003c`,
+ '>': `\u003e`,
'?': `\?`,
'[': `\[`,
'\\': `\\`,
diff --git a/src/text/template/funcs.go b/src/text/template/funcs.go
index 46125bc..f3de9fb 100644
--- a/src/text/template/funcs.go
+++ b/src/text/template/funcs.go
@@ -640,10 +640,10 @@ var (
jsBackslash = []byte(`\\`)
jsApos = []byte(`\'`)
jsQuot = []byte(`\"`)
- jsLt = []byte(`\x3C`)
- jsGt = []byte(`\x3E`)
- jsAmp = []byte(`\x26`)
- jsEq = []byte(`\x3D`)
+ jsLt = []byte(`\u003C`)
+ jsGt = []byte(`\u003E`)
+ jsAmp = []byte(`\u0026`)
+ jsEq = []byte(`\u003D`)
)
// JSEscape writes to w the escaped JavaScript equivalent of the plain text data b.
--
2.7.4