github.com/graybobo/golang.org-package-offline-cache@v0.0.0-20200626051047-6608995c132f/x/talks/2010/io/encrypt.go (about)

     1  // Copyright 2010 The Go Authors.  All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // +build OMIT
     6  
     7  // This code differs from the slides in that it handles errors.
     8  
     9  package main
    10  
    11  import (
    12  	"compress/gzip"
    13  	"crypto/aes"
    14  	"crypto/cipher"
    15  	"io"
    16  	"log"
    17  	"os"
    18  )
    19  
    20  func EncryptAndGzip(dstfile, srcfile string, key, iv []byte) error {
    21  	r, err := os.Open(srcfile)
    22  	if err != nil {
    23  		return err
    24  	}
    25  	var w io.WriteCloser
    26  	w, err = os.Create(dstfile)
    27  	if err != nil {
    28  		return err
    29  	}
    30  	defer w.Close()
    31  	w, err = gzip.NewWriter(w)
    32  	if err != nil {
    33  		return err
    34  	}
    35  	defer w.Close()
    36  	c, err := aes.NewCipher(key)
    37  	if err != nil {
    38  		return err
    39  	}
    40  	_, err = io.Copy(cipher.StreamWriter{S: cipher.NewOFB(c, iv), W: w}, r)
    41  	return err
    42  }
    43  
    44  func main() {
    45  	err := EncryptAndGzip(
    46  		"/tmp/passwd.gz",
    47  		"/etc/passwd",
    48  		make([]byte, 16),
    49  		make([]byte, 16),
    50  	)
    51  	if err != nil {
    52  		log.Fatal(err)
    53  	}
    54  }