Drop regex for canonicalization (#102)

* Drop regex for canonicalization

* Fix CI

.golangci.yml

@@ -30,3 +30,4 @@ linters:
     - gci               # Enforce blank lines check
     - nlreturn          # Enforce blank lines for return statements
     - exhaustivestruct  # Enforce structures to be fully filled on instantiation - terrible with openpgp configs
+    - paralleltest      # detects missing usage of t.Parallel() method in your Go test

CHANGELOG.md

@@ -4,6 +4,10 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## Unreleased
+### Changed
+- Improved canonicalization performance
+
 ## [2.1.1] 2020-11-16
 ### Changed
 - Session key decryption now considers multiple key packets 

crypto/message.go

@@ -88,7 +88,7 @@ func NewPlainMessageFromFile(data []byte, filename string, time uint32) *PlainMe
 // ready for encryption, signature, or verification from an unencrypted string.
 func NewPlainMessageFromString(text string) *PlainMessage {
 	return &PlainMessage{
-		Data:     []byte(strings.ReplaceAll(strings.ReplaceAll(text, "\r\n", "\n"), "\n", "\r\n")),
+		Data:     []byte(internal.CanonicalizeAndTrim(text)),
 		TextType: true,
 		Filename: "",
 		Time:     uint32(GetUnixTime()),

go.mod

@@ -12,4 +12,4 @@ require (
 
 replace golang.org/x/crypto => github.com/ProtonMail/crypto v0.0.0-20201112115411-41db4ea0dd1c
 
-replace golang.org/x/mobile => github.com/zhj4478/mobile v0.0.0-20201014085805-7a2d68bf792f
+replace golang.org/x/mobile => github.com/marinthiercelin/mobile v0.0.0-20201127122539-61ba718dc1d1

helper/cleartext.go

@@ -2,7 +2,6 @@ package helper
 
 import (
 	"github.com/ProtonMail/gopenpgp/v2/crypto"
-	"github.com/ProtonMail/gopenpgp/v2/internal"
 	"github.com/pkg/errors"
 )
 
@@ -49,7 +48,6 @@ func VerifyCleartextMessageArmored(publicKey, armored string, verifyTime int64)
 // SignCleartextMessage signs text given a private keyring, canonicalizes and
 // trims the newlines, and returns the PGP-compliant special armoring.
 func SignCleartextMessage(keyRing *crypto.KeyRing, text string) (string, error) {
-	text = internal.TrimWhitespace(text)
 	message := crypto.NewPlainMessageFromString(text)
 
 	signature, err := keyRing.SignDetached(message)

helper/cleartext_test.go

@@ -2,11 +2,11 @@ package helper
 
 import (
 	"regexp"
-	"strings"
 	"testing"
 
-	"github.com/ProtonMail/gopenpgp/v2/crypto"
 	"github.com/ProtonMail/gopenpgp/v2/internal"
+
+	"github.com/ProtonMail/gopenpgp/v2/crypto"
 	"github.com/stretchr/testify/assert"
 )
 
@@ -45,11 +45,5 @@ func TestSignClearText(t *testing.T) {
 	if err != nil {
 		t.Fatal("Cannot parse message:", err)
 	}
-	assert.Exactly(t, canonicalizeAndTrim(inputPlainText), string(clearTextMessage.GetBinary()))
-}
-
-func canonicalizeAndTrim(text string) string {
-	text = internal.TrimWhitespace(text)
-	text = strings.ReplaceAll(strings.ReplaceAll(text, "\r\n", "\n"), "\n", "\r\n")
-	return text
+	assert.Exactly(t, internal.CanonicalizeAndTrim(inputPlainText), string(clearTextMessage.GetBinary()))
 }

internal/common.go

@@ -2,16 +2,19 @@
 package internal
 
 import (
-	"regexp"
+	"strings"
 
 	"github.com/ProtonMail/gopenpgp/v2/constants"
 )
 
-// TrimWhitespace removes whitespace from the end of each line of the input
-// string.
-func TrimWhitespace(input string) string {
-	var re = regexp.MustCompile(`(?m)[ \t]*$`)
-	return re.ReplaceAllString(input, "")
+func CanonicalizeAndTrim(text string) string {
+	lines := strings.Split(text, "\n")
+
+	for i := range lines {
+		lines[i] = strings.TrimRight(lines[i], " \t\r")
+	}
+
+	return strings.Join(lines, "\r\n")
 }
 
 // CreationTimeOffset stores the amount of seconds that a signature may be