summaryrefslogtreecommitdiff
path: root/cryptfs/cryptfs_content.go
diff options
context:
space:
mode:
Diffstat (limited to 'cryptfs/cryptfs_content.go')
-rw-r--r--cryptfs/cryptfs_content.go17
1 files changed, 16 insertions, 1 deletions
diff --git a/cryptfs/cryptfs_content.go b/cryptfs/cryptfs_content.go
index e42011a..a4dc78a 100644
--- a/cryptfs/cryptfs_content.go
+++ b/cryptfs/cryptfs_content.go
@@ -7,8 +7,22 @@ import (
"os"
"errors"
"crypto/cipher"
+ "crypto/md5"
+ "encoding/hex"
)
+const (
+ // A block of 4124 zero bytes has this md5
+ ZeroBlockMd5 = "64331af89bd15a987b39855338336237"
+)
+
+// md5sum - debug helper, return md5 hex string
+func md5sum(buf []byte) string {
+ rawHash := md5.Sum(buf)
+ hash := hex.EncodeToString(rawHash[:])
+ return hash
+}
+
type CryptFile struct {
file *os.File
gcm cipher.AEAD
@@ -55,6 +69,7 @@ func (be *CryptFS) DecryptBlock(ciphertext []byte) ([]byte, error) {
// Extract nonce
nonce := ciphertext[:NONCE_LEN]
+ ciphertextOrig := ciphertext
ciphertext = ciphertext[NONCE_LEN:]
// Decrypt
@@ -63,7 +78,7 @@ func (be *CryptFS) DecryptBlock(ciphertext []byte) ([]byte, error) {
plaintext, err := be.gcm.Open(plaintext, nonce, ciphertext, nil)
if err != nil {
- Warn.Printf("DecryptBlock: %s\n", err.Error())
+ Warn.Printf("DecryptBlock: %s, len=%d, md5=%s\n", err.Error(), len(ciphertextOrig), Warn.Md5sum(ciphertextOrig))
return nil, err
}