diff options
| -rw-r--r-- | internal/fusefrontend_reverse/rfile.go | 29 |
1 files changed, 16 insertions, 13 deletions
diff --git a/internal/fusefrontend_reverse/rfile.go b/internal/fusefrontend_reverse/rfile.go index d363df9..26885a4 100644 --- a/internal/fusefrontend_reverse/rfile.go +++ b/internal/fusefrontend_reverse/rfile.go @@ -44,11 +44,11 @@ func (rf *reverseFile) GetAttr(*fuse.Attr) fuse.Status { return fuse.ENOSYS } -// readFile - read from the backing plaintext file, encrypt it, return the +// readBackingFile: read from the backing plaintext file, encrypt it, return the // ciphertext. // "off" ... ciphertext offset (must be >= HEADER_LEN) // "length" ... ciphertext length -func (rf *reverseFile) readFile(off uint64, length uint64) (out []byte, err error) { +func (rf *reverseFile) readBackingFile(off uint64, length uint64) (out []byte, err error) { blocks := rf.contentEnc.ExplodeCipherRange(off, length) // Read the backing plaintext in one go @@ -84,24 +84,27 @@ func (rf *reverseFile) Read(buf []byte, ioff int64) (resultData fuse.ReadResult, length := uint64(len(buf)) off := uint64(ioff) var out bytes.Buffer - var headerPart []byte + var header []byte - // Create a virtual file header + // Synthesize file header if off < contentenc.HEADER_LEN { - headerPart = zeroFileHeader.Pack() - headerPart = headerPart[off:] - if off+length < contentenc.HEADER_LEN { - headerPart = headerPart[:length] + header = zeroFileHeader.Pack() + // Truncate to requested part + end := int(off) + len(buf) + if end > len(header) { + end = len(header) } + header = header[off:end] + // Write into output buffer and adjust offsets + out.Write(header) + hLen := uint64(len(header)) + off += hLen + length -= hLen } - out.Write(headerPart) - hLen := uint64(len(headerPart)) - off += hLen - length -= hLen // Read actual file data if length > 0 { - fileData, err := rf.readFile(off, length) + fileData, err := rf.readBackingFile(off, length) if err != nil { return nil, fuse.ToStatus(err) } |