crypto/cipher: panic when IV length does not equal block size in NewOFB

Functions like NewCBCDecrypter, NewCBCEncrypter, NewCFBDecrypter,
NewCFBEncrypter and NewCTR all panic when IV length does not equal block size.
This commit changes NewOFB to panic too, instead of returning nil silently.

Change-Id: Ic4d3ebfad79bb0cf4759fa1c1a400c1a8d043490
Reviewed-on: https://go-review.googlesource.com/61850
Reviewed-by: Filippo Valsorda <hi@filippo.io>
Run-TryBot: Filippo Valsorda <hi@filippo.io>
TryBot-Result: Gobot Gobot <gobot@golang.org>

diff --git a/src/crypto/cipher/ofb.go b/src/crypto/cipher/ofb.go
index e86ebcb237ee3ce2ef203c92adaaa94042d94d46..7b35f8995c8e71c4b1eabd8549d2483a4d37e44a 100644 (file)
--- a/src/crypto/cipher/ofb.go
+++ b/src/crypto/cipher/ofb.go
@@ -19,7 +19,7 @@ type ofb struct {
 func NewOFB(b Block, iv []byte) Stream {
        blockSize := b.BlockSize()
        if len(iv) != blockSize {
-               return nil
+               panic("cipher.NewOFB: IV length must equal block size")
        }
        bufSize := streamBufferSize
        if bufSize < blockSize {