Fix recovery middleware to render gitea style page. (#13857)

* Some changes to fix recovery

* Move Recovery to middlewares

* Remove trace code

* Fix lint

* add session middleware and remove dependent on macaron for sso

* Fix panic 500 page rendering

* Fix bugs

* Fix fmt

* Fix vendor

* recover unnecessary change

* Fix lint and addd some comments about the copied codes.

* Use util.StatDir instead of com.StatDir

Co-authored-by: 6543 <6543@obermui.de>

vendor/gitea.com/go-chi/session/secret.go

@@ -0,0 +1,100 @@
+// Copyright 2019 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package session
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/rand"
+	"crypto/sha256"
+	"encoding/base64"
+	"errors"
+	"io"
+)
+
+// NewSecret creates a new secret
+func NewSecret() (string, error) {
+	return NewSecretWithLength(32)
+}
+
+// NewSecretWithLength creates a new secret for a given length
+func NewSecretWithLength(length int64) (string, error) {
+	return randomString(length)
+}
+
+func randomBytes(len int64) ([]byte, error) {
+	b := make([]byte, len)
+	if _, err := rand.Read(b); err != nil {
+		return nil, err
+	}
+	return b, nil
+}
+
+func randomString(len int64) (string, error) {
+	b, err := randomBytes(len)
+	return base64.URLEncoding.EncodeToString(b), err
+}
+
+// AesEncrypt encrypts text and given key with AES.
+func AesEncrypt(key, text []byte) ([]byte, error) {
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+	b := base64.StdEncoding.EncodeToString(text)
+	ciphertext := make([]byte, aes.BlockSize+len(b))
+	iv := ciphertext[:aes.BlockSize]
+	if _, err := io.ReadFull(rand.Reader, iv); err != nil {
+		return nil, err
+	}
+	cfb := cipher.NewCFBEncrypter(block, iv)
+	cfb.XORKeyStream(ciphertext[aes.BlockSize:], []byte(b))
+	return ciphertext, nil
+}
+
+// AesDecrypt decrypts text and given key with AES.
+func AesDecrypt(key, text []byte) ([]byte, error) {
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		return nil, err
+	}
+	if len(text) < aes.BlockSize {
+		return nil, errors.New("ciphertext too short")
+	}
+	iv := text[:aes.BlockSize]
+	text = text[aes.BlockSize:]
+	cfb := cipher.NewCFBDecrypter(block, iv)
+	cfb.XORKeyStream(text, text)
+	data, err := base64.StdEncoding.DecodeString(string(text))
+	if err != nil {
+		return nil, err
+	}
+	return data, nil
+}
+
+// EncryptSecret encrypts a string with given key into a hex string
+func EncryptSecret(key string, str string) (string, error) {
+	keyHash := sha256.Sum256([]byte(key))
+	plaintext := []byte(str)
+	ciphertext, err := AesEncrypt(keyHash[:], plaintext)
+	if err != nil {
+		return "", err
+	}
+	return base64.StdEncoding.EncodeToString(ciphertext), nil
+}
+
+// DecryptSecret decrypts a previously encrypted hex string
+func DecryptSecret(key string, cipherhex string) (string, error) {
+	keyHash := sha256.Sum256([]byte(key))
+	ciphertext, err := base64.StdEncoding.DecodeString(cipherhex)
+	if err != nil {
+		return "", err
+	}
+	plaintext, err := AesDecrypt(keyHash[:], ciphertext)
+	if err != nil {
+		return "", err
+	}
+	return string(plaintext), nil
+}