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Diffstat (limited to 'cryptfs/address_translation.go')
-rw-r--r--cryptfs/address_translation.go89
1 files changed, 0 insertions, 89 deletions
diff --git a/cryptfs/address_translation.go b/cryptfs/address_translation.go
deleted file mode 100644
index b21cfc7..0000000
--- a/cryptfs/address_translation.go
+++ /dev/null
@@ -1,89 +0,0 @@
-package cryptfs
-
-// CryptFS methods that translate offsets between ciphertext and plaintext
-
-// get the block number at plain-text offset
-func (be *CryptFS) PlainOffToBlockNo(plainOffset uint64) uint64 {
- return plainOffset / be.plainBS
-}
-
-// get the block number at ciphter-text offset
-func (be *CryptFS) CipherOffToBlockNo(cipherOffset uint64) uint64 {
- return (cipherOffset - HEADER_LEN) / be.cipherBS
-}
-
-// get ciphertext offset of block "blockNo"
-func (be *CryptFS) BlockNoToCipherOff(blockNo uint64) uint64 {
- return HEADER_LEN + blockNo*be.cipherBS
-}
-
-// get plaintext offset of block "blockNo"
-func (be *CryptFS) BlockNoToPlainOff(blockNo uint64) uint64 {
- return blockNo * be.plainBS
-}
-
-// PlainSize - calculate plaintext size from ciphertext size
-func (be *CryptFS) CipherSizeToPlainSize(cipherSize uint64) uint64 {
-
- // Zero sized files stay zero-sized
- if cipherSize == 0 {
- return 0
- }
-
- if cipherSize == HEADER_LEN {
- Warn.Printf("cipherSize %d == header size: interrupted write?\n", cipherSize)
- return 0
- }
-
- if cipherSize < HEADER_LEN {
- Warn.Printf("cipherSize %d < header size: corrupt file\n", cipherSize)
- return 0
- }
-
- // Block number at last byte
- blockNo := be.CipherOffToBlockNo(cipherSize - 1)
- blockCount := blockNo + 1
-
- overhead := be.BlockOverhead()*blockCount + HEADER_LEN
-
- return cipherSize - overhead
-}
-
-// CipherSize - calculate ciphertext size from plaintext size
-func (be *CryptFS) PlainSizeToCipherSize(plainSize uint64) uint64 {
-
- // Block number at last byte
- blockNo := be.PlainOffToBlockNo(plainSize - 1)
- blockCount := blockNo + 1
-
- overhead := be.BlockOverhead()*blockCount + HEADER_LEN
-
- return plainSize + overhead
-}
-
-// Split a plaintext byte range into (possibly partial) blocks
-func (be *CryptFS) ExplodePlainRange(offset uint64, length uint64) []intraBlock {
- var blocks []intraBlock
- var nextBlock intraBlock
- nextBlock.fs = be
-
- for length > 0 {
- nextBlock.BlockNo = be.PlainOffToBlockNo(offset)
- nextBlock.Skip = offset - be.BlockNoToPlainOff(nextBlock.BlockNo)
-
- // Minimum of remaining data and remaining space in the block
- nextBlock.Length = MinUint64(length, be.plainBS-nextBlock.Skip)
-
- blocks = append(blocks, nextBlock)
- offset += nextBlock.Length
- length -= nextBlock.Length
- }
- return blocks
-}
-
-func MinUint64(x uint64, y uint64) uint64 {
- if x < y {
- return x
- }
- return y
-}