TBR: gzip the content of the messages
Compress the content of the messages before encrypting them, and
decompress them after decrypting them.
Change-Id: I040450c4b2fa3d92949846d06505fd4786f5fa7f
diff --git a/internal/util.go b/internal/util.go
index 104faf5..2048a09 100644
--- a/internal/util.go
+++ b/internal/util.go
@@ -15,10 +15,6 @@
"messenger/ifc"
)
-func NewMessageId() string {
- return uuid.New()
-}
-
// NewMessageFromFile creates a new Message for the content of the given file.
// The Message's Id, CreationTime, Length, and Sha256 fields are populated.
func NewMessageFromFile(file string) (ifc.Message, error) {
@@ -44,7 +40,7 @@
}
}
return ifc.Message{
- Id: NewMessageId(),
+ Id: uuid.New(),
CreationTime: time.Now(),
Length: size,
Sha256: h.Sum(nil),
@@ -57,7 +53,7 @@
h := sha256.New()
h.Write(b)
return ifc.Message{
- Id: NewMessageId(),
+ Id: uuid.New(),
CreationTime: time.Now(),
Length: int64(len(b)),
Sha256: h.Sum(nil),
diff --git a/vmsg/chat.go b/vmsg/chat.go
index a07ab6e..f9d48b7 100644
--- a/vmsg/chat.go
+++ b/vmsg/chat.go
@@ -8,6 +8,8 @@
package main
import (
+ "compress/gzip"
+ "errors"
"fmt"
"io"
"io/ioutil"
@@ -255,7 +257,7 @@
if err != nil {
return
}
- msgText, filename, err := decryptChatMessage(msg.Id, r, incomingDir)
+ msgText, filename, err := decryptChatMessage(r, incomingDir)
r.Close()
if err != nil {
a.printErrorf("*** Unable to handle message: %v\n", err)
@@ -310,8 +312,7 @@
func (m messages) Swap(i, j int) { m[i], m[j] = m[j], m[i] }
func sendMessage(ctx *context.T, ps *internal.PubSub, store internal.MessengerStorage, txt, fname string) error {
- msgId := internal.NewMessageId()
- encryptedFile, err := encryptChatMessage(msgId, txt, fname)
+ encryptedFile, err := encryptChatMessage(txt, fname)
if err != nil {
return err
}
@@ -322,7 +323,6 @@
if err != nil {
return err
}
- msg.Id = msgId
msg.SenderBlessings, _ = p.BlessingStore().Default()
msg.Lifespan = 15 * time.Minute
var expiry time.Time
@@ -357,7 +357,7 @@
return nil
}
-func encryptChatMessage(id, text, attachment string) (string, error) {
+func encryptChatMessage(text, attachment string) (string, error) {
tmpfile, err := ioutil.TempFile("", "vmsg-encrypt-")
if err != nil {
return "", err
@@ -367,10 +367,12 @@
if err != nil {
return "", err
}
- w := multipart.NewWriter(enc)
- if err := w.SetBoundary(id); err != nil {
+ comp, err := gzip.NewWriterLevel(enc, compressionLevel)
+ if err != nil {
return "", err
}
+ w := multipart.NewWriter(comp)
+ comp.Header.Extra = []byte(w.Boundary())
// Write text field.
if err := w.WriteField("text", text); err != nil {
@@ -394,15 +396,26 @@
if err := w.Close(); err != nil {
return "", err
}
+ if err := comp.Close(); err != nil {
+ return "", err
+ }
return tmpfile.Name(), nil
}
-func decryptChatMessage(id string, msgReader io.Reader, dir string) (text, filename string, err error) {
+func decryptChatMessage(msgReader io.Reader, dir string) (text, filename string, err error) {
dec, err := aesDecoder(encryptionKey, msgReader)
if err != nil {
return "", "", err
}
- r := multipart.NewReader(dec, id)
+ decomp, err := gzip.NewReader(dec)
+ if err != nil {
+ if err == gzip.ErrHeader {
+ return "", "", errors.New("incorrect key")
+ }
+ return "", "", err
+ }
+ defer decomp.Close()
+ r := multipart.NewReader(decomp, string(decomp.Header.Extra))
form, err := r.ReadForm(1 << 20)
if err != nil {
return "", "", err
diff --git a/vmsg/main.go b/vmsg/main.go
index bae7339..97f8559 100644
--- a/vmsg/main.go
+++ b/vmsg/main.go
@@ -52,7 +52,8 @@
rateAclSenderJson string
encryptionKey string
- incomingDir string
+ incomingDir string
+ compressionLevel int
)
func main() {
@@ -74,6 +75,7 @@
cmdRoot.Flags.StringVar(&encryptionKey, "encryption-key", defaultEncryptionKey, "Messages are encrypted with AES256 using this key")
cmdChat.Flags.StringVar(&incomingDir, "incoming-dir", os.TempDir(), "The directory where to save incoming files")
+ cmdChat.Flags.IntVar(&compressionLevel, "compression-level", -1, "The gzip compression level for the message content. A value of -1 means default compressions; 1 is best speed; 9 is best compression.")
cmdline.HideGlobalFlagsExcept()
cmdline.Main(cmdRoot)
diff --git a/vmsg/robot.go b/vmsg/robot.go
index 0aa5477..331d89d 100644
--- a/vmsg/robot.go
+++ b/vmsg/robot.go
@@ -85,7 +85,7 @@
if err != nil {
continue
}
- msgText, filename, err := decryptChatMessage(msg.Id, r, incomingDir)
+ msgText, filename, err := decryptChatMessage(r, incomingDir)
r.Close()
if err != nil {
ctx.Infof("decryptChatMessage failed: %v", err)
