crypto/attachments: hash correct data while decrypting

tulir · tulir · commit 5d84bddc62e6 · 2025-08-11T10:58:24.000+03:00
diff --git a/crypto/attachment/attachments.go b/crypto/attachment/attachments.go
@@ -207,8 +207,13 @@ func (r *encryptingReader) Read(dst []byte) (n int, err error) {
 		}
 	}
 	n, err = r.source.Read(dst)
+	if r.isDecrypting {
+		r.hash.Write(dst[:n])
+	}
 	r.stream.XORKeyStream(dst[:n], dst[:n])
-	r.hash.Write(dst[:n])
+	if !r.isDecrypting {
+		r.hash.Write(dst[:n])
+	}
 	return
 }
 

Original file line number	Diff line number	Diff line change
`@@ -207,8 +207,13 @@ func (r *encryptingReader) Read(dst []byte) (n int, err error) {`
`207`	`207`	`}`
`208`	`208`	`}`
`209`	`209`	`n, err = r.source.Read(dst)`
	`210`	`+ if r.isDecrypting {`
	`211`	`+ r.hash.Write(dst[:n])`
	`212`	`+ }`
`210`	`213`	`r.stream.XORKeyStream(dst[:n], dst[:n])`
`211`		`- r.hash.Write(dst[:n])`
	`214`	`+ if !r.isDecrypting {`
	`215`	`+ r.hash.Write(dst[:n])`
	`216`	`+ }`
`212`	`217`	`return`
`213`	`218`	`}`
`214`	`219`