diff options
Diffstat (limited to 'cryptfs/openssl_aead.go')
-rw-r--r-- | cryptfs/openssl_aead.go | 100 |
1 files changed, 0 insertions, 100 deletions
diff --git a/cryptfs/openssl_aead.go b/cryptfs/openssl_aead.go deleted file mode 100644 index 5d38d38..0000000 --- a/cryptfs/openssl_aead.go +++ /dev/null @@ -1,100 +0,0 @@ -package cryptfs - -// Implements cipher.AEAD with OpenSSL backend - -import ( - "bytes" - "github.com/spacemonkeygo/openssl" -) - -// Supports all nonce sizes -type opensslGCM struct { - key []byte -} - -func (be opensslGCM) Overhead() int { - return AUTH_TAG_LEN -} - -func (be opensslGCM) NonceSize() int { - // We support any nonce size - return -1 -} - -// Seal encrypts and authenticates plaintext, authenticates the -// additional data and appends the result to dst, returning the updated -// slice. opensslGCM supports any nonce size. -func (be opensslGCM) Seal(dst, nonce, plaintext, data []byte) []byte { - - // Preallocate output buffer - var cipherBuf bytes.Buffer - cipherBuf.Grow(len(dst) + len(plaintext) + AUTH_TAG_LEN) - // Output will be appended to dst - cipherBuf.Write(dst) - - ectx, err := openssl.NewGCMEncryptionCipherCtx(KEY_LEN*8, nil, be.key, nonce) - if err != nil { - panic(err) - } - err = ectx.ExtraData(data) - if err != nil { - panic(err) - } - part, err := ectx.EncryptUpdate(plaintext) - if err != nil { - panic(err) - } - cipherBuf.Write(part) - part, err = ectx.EncryptFinal() - if err != nil { - panic(err) - } - cipherBuf.Write(part) - part, err = ectx.GetTag() - if err != nil { - panic(err) - } - cipherBuf.Write(part) - - return cipherBuf.Bytes() -} - -// Open decrypts and authenticates ciphertext, authenticates the -// additional data and, if successful, appends the resulting plaintext -// to dst, returning the updated slice. The nonce must be NonceSize() -// bytes long and both it and the additional data must match the -// value passed to Seal. -// -// The ciphertext and dst may alias exactly or not at all. -func (be opensslGCM) Open(dst, nonce, ciphertext, data []byte) ([]byte, error) { - - l := len(ciphertext) - tag := ciphertext[l-AUTH_TAG_LEN : l] - ciphertext = ciphertext[0 : l-AUTH_TAG_LEN] - plainBuf := bytes.NewBuffer(dst) - - dctx, err := openssl.NewGCMDecryptionCipherCtx(KEY_LEN*8, nil, be.key, nonce) - if err != nil { - return nil, err - } - err = dctx.ExtraData(data) - if err != nil { - return nil, err - } - part, err := dctx.DecryptUpdate(ciphertext) - if err != nil { - return nil, err - } - plainBuf.Write(part) - err = dctx.SetTag(tag) - if err != nil { - return nil, err - } - part, err = dctx.DecryptFinal() - if err != nil { - return nil, err - } - plainBuf.Write(part) - - return plainBuf.Bytes(), nil -} |