From 05a5c0a0fffb4cb27c6e2dccda42d18ee067631c Mon Sep 17 00:00:00 2001
From: Jakob Unterwurzacher
Date: Sat, 5 Sep 2015 11:49:05 +0200
Subject: Wrap cluefs part I

---
 cryptfs/file.go | 148 --------------------------------------------------------
 1 file changed, 148 deletions(-)
 delete mode 100644 cryptfs/file.go

(limited to 'cryptfs/file.go')

diff --git a/cryptfs/file.go b/cryptfs/file.go
deleted file mode 100644
index 5645f3c..0000000
--- a/cryptfs/file.go
+++ /dev/null
@@ -1,148 +0,0 @@
-package cryptfs
-
-import (
-	"fmt"
-	"os"
-	"io"
-	"errors"
-	"crypto/cipher"
-)
-
-type CryptFile struct {
-	file *os.File
-	gcm cipher.AEAD
-	plainBS	int64
-	cipherBS int64
-}
-
-// readCipherBlock - Read ciphertext block number "blockNo", decrypt,
-// return plaintext
-func (be *CryptFile) readCipherBlock(blockNo int64) ([]byte, error) {
-	off := blockNo * int64(be.cipherBS)
-	buf := make([]byte, be.cipherBS)
-
-	readN, err := be.file.ReadAt(buf, off)
-
-	if err != nil && err != io.EOF {
-		return nil, err
-	}
-
-	// Truncate buffer to actually read bytes
-	buf = buf[:readN]
-
-	// Empty block?file:///home/jakob/go/src/github.com/rfjakob/gocryptfs-bazil/backend/backend.go
-
-	if len(buf) == 0 {
-		return buf, nil
-	}
-
-	if len(buf) < NONCE_LEN {
-		warn.Printf("readCipherBlock: Block is too short: %d bytes\n", len(buf))
-		return nil, errors.New("Block is too short")
-	}
-
-	// Extract nonce
-	nonce := buf[:NONCE_LEN]
-	buf = buf[NONCE_LEN:]
-
-	// Decrypt
-	var plainBuf []byte
-	plainBuf, err = be.gcm.Open(plainBuf, nonce, buf, nil)
-	if err != nil {
-		fmt.Printf("gcm.Open() failed: %d\n", err)
-		return nil, err
-	}
-
-	return plainBuf, nil
-}
-
-// intraBlock identifies a part of a file block
-type intraBlock struct {
-	blockNo int64  // Block number in file
-	offset  int64  // Offset into block plaintext
-	length  int64  // Length of data from this block
-}
-
-// Split a plaintext byte range into (possible partial) blocks
-func (be *CryptFile) splitRange(offset int64, length int64) []intraBlock {
-	var b intraBlock
-	var parts []intraBlock
-
-	for length > 0 {
-		b.blockNo = offset / be.plainBS
-		b.offset = offset % be.plainBS
-		b.length = be.min64(length, be.plainBS - b.offset)
-		parts = append(parts, b)
-		offset += b.length
-		length -= b.length
-	}
-	return parts
-}
-
-func (be *CryptFile) min64(x int64, y int64) int64 {
-	if x < y {
-		return x
-	}
-	return y
-}
-
-// writeCipherBlock - Encrypt plaintext and write it to file block "blockNo"
-func (be *CryptFile) writeCipherBlock(blockNo int64, plain []byte) error {
-
-	if int64(len(plain)) > be.plainBS {
-		panic("writeCipherBlock: Cannot write block that is larger than plainBS")
-	}
-
-	// Get fresh nonce
-	nonce := gcmNonce.Get()
-	// Encrypt data and append to nonce
-	cipherBuf := be.gcm.Seal(nonce, nonce, plain, nil)
-
-	// WriteAt retries short writes autmatically
-	written, err := be.file.WriteAt(cipherBuf, blockNo * be.cipherBS)
-
-	debug.Printf("writeCipherBlock: wrote %d ciphertext bytes to block %d\n",
-		written, blockNo)
-
-	return err
-}
-
-// Perform RMW cycle on block
-// Write "data" into file location specified in "b"
-func (be *CryptFile) rmwWrite(b intraBlock, data []byte, f *os.File) error {
-	if b.length != int64(len(data)) {
-		panic("Length mismatch")
-	}
-
-	oldBlock, err := be.readCipherBlock(b.blockNo)
-	if err != nil {
-		return err
-	}
-	newBlockLen := b.offset + b.length
-	debug.Printf("newBlockLen := %d + %d\n", b.offset, b.length)
-	var newBlock []byte
-
-	// Write goes beyond the old block and grows the file?
-	// Must create a bigger newBlock
-	if newBlockLen > int64(len(oldBlock)) {
-		newBlock = make([]byte, newBlockLen)
-	} else {
-		newBlock = make([]byte, len(oldBlock))
-	}
-
-	// Fill with old data
-	copy(newBlock, oldBlock)
-	// Then overwrite the relevant parts with new data
-	copy(newBlock[b.offset:b.offset + b.length], data)
-
-	// Actual write
-	err = be.writeCipherBlock(b.blockNo, newBlock)
-
-	if err != nil {
-		// An incomplete write to a ciphertext block means that the whole block
-		// is destroyed.
-		fmt.Printf("rmwWrite: Write error: %s\n", err)
-	}
-
-	return err
-}
-- 
cgit v1.2.3