86 lines
1.9 KiB
Go
86 lines
1.9 KiB
Go
package main
|
|
|
|
import (
|
|
"encoding/hex"
|
|
"flag"
|
|
"fmt"
|
|
"io"
|
|
"os"
|
|
|
|
"github.com/rfjakob/gocryptfs/internal/contentenc"
|
|
"github.com/rfjakob/gocryptfs/internal/cryptocore"
|
|
)
|
|
|
|
const (
|
|
IVLen = contentenc.DefaultIVBits / 8
|
|
blockSize = contentenc.DefaultBS + IVLen + cryptocore.AuthTagLen
|
|
)
|
|
|
|
func errExit(err error) {
|
|
fmt.Println(err)
|
|
os.Exit(1)
|
|
}
|
|
|
|
func prettyPrintHeader(h *contentenc.FileHeader) {
|
|
id := hex.EncodeToString(h.Id)
|
|
fmt.Printf("Header: Version: %d, Id: %s\n", h.Version, id)
|
|
}
|
|
|
|
func main() {
|
|
flag.Parse()
|
|
if flag.NArg() != 1 {
|
|
fmt.Printf("Usage: xray FILE\n")
|
|
os.Exit(1)
|
|
}
|
|
f := flag.Arg(0)
|
|
fd, err := os.Open(f)
|
|
if err != nil {
|
|
errExit(err)
|
|
}
|
|
|
|
headerBytes := make([]byte, contentenc.HEADER_LEN)
|
|
n, err := fd.ReadAt(headerBytes, 0)
|
|
if err == io.EOF && n == 0 {
|
|
fmt.Println("empty file")
|
|
os.Exit(0)
|
|
} else if err == io.EOF {
|
|
fmt.Printf("incomplete file header: read %d bytes, want %d\n", n, contentenc.HEADER_LEN)
|
|
os.Exit(1)
|
|
} else if err != nil {
|
|
errExit(err)
|
|
}
|
|
header, err := contentenc.ParseHeader(headerBytes)
|
|
if err != nil {
|
|
errExit(err)
|
|
}
|
|
prettyPrintHeader(header)
|
|
var i int64
|
|
for i = 0; ; i++ {
|
|
blockLen := int64(blockSize)
|
|
off := contentenc.HEADER_LEN + i*blockSize
|
|
iv := make([]byte, IVLen)
|
|
_, err := fd.ReadAt(iv, off)
|
|
if err == io.EOF {
|
|
break
|
|
} else if err != nil {
|
|
errExit(err)
|
|
}
|
|
tag := make([]byte, cryptocore.AuthTagLen)
|
|
_, err = fd.ReadAt(tag, off+blockSize-cryptocore.AuthTagLen)
|
|
if err == io.EOF {
|
|
fi, err2 := fd.Stat()
|
|
if err2 != nil {
|
|
errExit(err2)
|
|
}
|
|
_, err2 = fd.ReadAt(tag, fi.Size()-cryptocore.AuthTagLen)
|
|
if err2 != nil {
|
|
errExit(err2)
|
|
}
|
|
blockLen = (fi.Size() - contentenc.HEADER_LEN) % blockSize
|
|
} else if err != nil {
|
|
errExit(err)
|
|
}
|
|
fmt.Printf("Block %2d: IV: %s, Tag: %s, Len: %d\n", i, hex.EncodeToString(iv), hex.EncodeToString(tag), blockLen)
|
|
}
|
|
}
|