🏓 Fix padding handling

database64128 · database64128 · commit 32bd3d68e58e · 2022-03-27T04:58:38.000+08:00
diff --git a/shadowsocks/header.go b/shadowsocks/header.go
@@ -105,7 +105,7 @@ func ParseTCPReqHeader(r Reader, cipherConfig CipherConfig) (string, []byte, err
 
 		// Skip padding.
 		offset += paddingLen
-		if offset >= len(b) {
+		if offset > len(b) {
 			return "", nil, ErrPaddingExceedChunkBorder
 		}
 	}
@@ -298,7 +298,7 @@ func WriteRandomPadding(b []byte, targetPort int, max int) int {
 		return 2
 	}
 
-	paddingLen := rand.Intn(max)
+	paddingLen := rand.Intn(max + 1)
 	binary.BigEndian.PutUint16(b, uint16(paddingLen))
 	return 2 + paddingLen
 }

Original file line number	Diff line number	Diff line change
`@@ -105,7 +105,7 @@ func ParseTCPReqHeader(r Reader, cipherConfig CipherConfig) (string, []byte, err`
`105`	`105`
`106`	`106`	`// Skip padding.`
`107`	`107`	`offset += paddingLen`
`108`		`- if offset >= len(b) {`
	`108`	`+ if offset > len(b) {`
`109`	`109`	`return "", nil, ErrPaddingExceedChunkBorder`
`110`	`110`	`}`
`111`	`111`	`}`
`@@ -298,7 +298,7 @@ func WriteRandomPadding(b []byte, targetPort int, max int) int {`
`298`	`298`	`return 2`
`299`	`299`	`}`
`300`	`300`
`301`		`- paddingLen := rand.Intn(max)`
	`301`	`+ paddingLen := rand.Intn(max + 1)`
`302`	`302`	`binary.BigEndian.PutUint16(b, uint16(paddingLen))`
`303`	`303`	`return 2 + paddingLen`
`304`	`304`	`}`