Adding Github & Gitea OAuth provider

README.md

@@ -13,6 +13,7 @@ A self-hosted pastebin **powered by Git**. [Try it here](https://opengist.thomic
 * [Administration](#administration)
  * [Use Nginx as a reverse proxy](#use-nginx-as-a-reverse-proxy)
  * [Use Fail2ban](#use-fail2ban)
+* [Configure OAuth](#configure-oauth)
 * [License](#license)
 
 ## Features
@@ -170,6 +171,37 @@ Then run
 ```shell
 service fail2ban restart 
 ```
+
+## Configure OAuth
+
+Opengist can be configured to use OAuth to authenticate users, with GitHub or Gitea.
+
+<details>
+<summary>Integrate Github</summary>
+
+* Add a new OAuth app in your [Github account settings](https://github.com/settings/applications/new)
+* Set 'Authorization callback URL' to `http:https://opengist.domain/oauth/github/callback`
+* Copy the 'Client ID' and 'Client Secret' and add them to the `config.yml` file :
+ ```yaml
+ github.client-key: <key>
+ github.secret: <secret>
+ ```
+</details>
+
+<details>
+<summary>Integrate Gitea</summary>
+
+* Add a new OAuth app in Application settings from the [Gitea instance](https://gitea.com/user/settings/applications)
+* Set 'Redirect URI' to `http:https://opengist.domain/oauth/gitea/callback`
+* Copy the 'Client ID' and 'Client Secret' and add them to the `config.yml` file :
+ ```yaml
+ gitea.client-key: <key>
+ gitea.secret: <secret>
+ # URL of the Gitea instance. Default: https://gitea.com/
+ gitea.url: http:https://localhost:3000
+ ```
+</details>
+
 ## License
 
 Opengist is licensed under the [AGPL-3.0 license](LICENSE).

config.yml

@@ -53,3 +53,17 @@ ssh.external-domain:
 
 # Path or alias to ssh-keygen executable. Default: ssh-keygen
 ssh.keygen-executable: ssh-keygen
+
+
+# OAuth2 configuration
+# The callback/redirect URL must be http:https://opengist.domain/oauth/<github|gitea>/callback
+
+# To create a new OAuth2 application using GitHub : https://github.com/settings/applications/new
+github.client-key:
+github.secret:
+
+# To create a new OAuth2 application using Gitea : https://gitea.domain/user/settings/applications
+gitea.client-key:
+gitea.secret:
+# URL of the Gitea instance. Default: https://gitea.com/
+gitea.url: https://gitea.com/

go.mod

@@ -7,6 +7,8 @@ require (
  github.com/google/uuid v1.3.0
  github.com/gorilla/sessions v1.2.1
  github.com/labstack/echo/v4 v4.10.0
+ github.com/markbates/goth v1.77.0
+ github.com/mattn/go-sqlite3 v1.14.13
  github.com/rs/zerolog v1.29.0
  golang.org/x/crypto v0.2.0
  gopkg.in/yaml.v3 v3.0.1
@@ -18,18 +20,23 @@ require (
  github.com/go-playground/locales v0.14.0 // indirect
  github.com/go-playground/universal-translator v0.18.0 // indirect
  github.com/golang-jwt/jwt v3.2.2+incompatible // indirect
+ github.com/golang/protobuf v1.4.2 // indirect
+ github.com/gorilla/context v1.1.1 // indirect
+ github.com/gorilla/mux v1.6.2 // indirect
  github.com/gorilla/securecookie v1.1.1 // indirect
  github.com/jinzhu/inflection v1.0.0 // indirect
  github.com/jinzhu/now v1.1.5 // indirect
  github.com/labstack/gommon v0.4.0 // indirect
  github.com/leodido/go-urn v1.2.1 // indirect
  github.com/mattn/go-colorable v0.1.13 // indirect
  github.com/mattn/go-isatty v0.0.17 // indirect
- github.com/mattn/go-sqlite3 v1.14.13 // indirect
  github.com/valyala/bytebufferpool v1.0.0 // indirect
  github.com/valyala/fasttemplate v1.2.2 // indirect
  golang.org/x/net v0.4.0 // indirect
+ golang.org/x/oauth2 v0.0.0-20200902213428-5d25da1a8d43 // indirect
  golang.org/x/sys v0.5.0 // indirect
  golang.org/x/text v0.5.0 // indirect
  golang.org/x/time v0.2.0 // indirect
+ google.golang.org/appengine v1.6.6 // indirect
+ google.golang.org/protobuf v1.25.0 // indirect
 )

internal/config/config.go

@@ -35,6 +35,13 @@ type config struct {
  SshPort string `yaml:"ssh.port"`
  SshExternalDomain string `yaml:"ssh.external-domain"`
  SshKeygen string `yaml:"ssh.keygen-executable"`
+
+ GithubClientKey string `yaml:"github.client-key"`
+ GithubSecret string `yaml:"github.secret"`
+
+ GiteaClientKey string `yaml:"gitea.client-key"`
+ GiteaSecret string `yaml:"gitea.secret"`
+ GiteaUrl string `yaml:"gitea.url"`
 }
 
 func configWithDefaults() (*config, error) {
@@ -58,6 +65,8 @@ func configWithDefaults() (*config, error) {
  c.SshPort = "2222"
  c.SshKeygen = "ssh-keygen"
 
+ c.GiteaUrl = "http:https://gitea.com"
+
  return c, nil
 }
 

internal/models/admin_setting.go

@@ -1,8 +1,6 @@
 package models
 
 import (
- "errors"
- "github.com/mattn/go-sqlite3"
  "gorm.io/gorm/clause"
 )
 
@@ -38,19 +36,11 @@ func setSetting(key string, value string) error {
 func initAdminSettings(settings map[string]string) error {
  for key, value := range settings {
  if err := setSetting(key, value); err != nil {
- if !isUniqueConstraintViolation(err) {
+ if !IsUniqueConstraintViolation(err) {
  return err
  }
  }
  }
 
  return nil
 }
-
-func isUniqueConstraintViolation(err error) bool {
- var sqliteErr sqlite3.Error
- if errors.As(err, &sqliteErr) && sqliteErr.ExtendedCode == sqlite3.ErrConstraintUnique {
- return true
- }
- return false
-}

internal/models/db.go

@@ -1,6 +1,8 @@
 package models
 
 import (
+ "errors"
+ "github.com/mattn/go-sqlite3"
  "gorm.io/driver/sqlite"
  "gorm.io/gorm"
  "gorm.io/gorm/logger"
@@ -32,3 +34,11 @@ func CountAll(table interface{}) (int64, error) {
  err := db.Model(table).Count(&count).Error
  return count, err
 }
+
+func IsUniqueConstraintViolation(err error) bool {
+ var sqliteErr sqlite3.Error
+ if errors.As(err, &sqliteErr) && sqliteErr.ExtendedCode == sqlite3.ErrConstraintUnique {
+ return true
+ }
+ return false
+}

internal/models/sshkey.go

@@ -1,6 +1,12 @@
 package models
 
-import "time"
+import (
+ "crypto/sha256"
+ "encoding/base64"
+ "golang.org/x/crypto/ssh"
+ "gorm.io/gorm"
+ "time"
+)
 
 type SSHKey struct {
  ID uint `gorm:"primaryKey"`
@@ -13,6 +19,16 @@ type SSHKey struct {
  User User `validate:"-" `
 }
 
+func (sshKey *SSHKey) BeforeCreate(tx *gorm.DB) error {
+ pubKey, _, _, _, err := ssh.ParseAuthorizedKey([]byte(sshKey.Content))
+ if err != nil {
+ return err
+ }
+ sha := sha256.Sum256(pubKey.Marshal())
+ sshKey.SHA = base64.StdEncoding.EncodeToString(sha[:])
+ return nil
+}
+
 func GetSSHKeysByUserID(userId uint) ([]*SSHKey, error) {
  var sshKeys []*SSHKey
  err := db.

internal/models/user.go

@@ -12,6 +12,8 @@ type User struct {
  CreatedAt int64
  Email string
  MD5Hash string // for gravatar, if no Email is specified, the value is random
+ GithubID string
+ GiteaID string
 
  Gists []Gist `gorm:"constraint:OnUpdate:CASCADE,OnDelete:CASCADE;foreignKey:UserID"`
  SSHKeys []SSHKey `gorm:"foreignKey:UserID"`
@@ -90,6 +92,19 @@ func GetUserBySSHKeyID(sshKeyId uint) (*User, error) {
  return user, err
 }
 
+func GetUserByProvider(id string, provider string) (*User, error) {
+ user := new(User)
+ var err error
+ switch provider {
+ case "github":
+ err = db.Where("github_id = ?", id).First(&user).Error
+ case "gitea":
+ err = db.Where("gitea_id = ?", id).First(&user).Error
+ }
+
+ return user, err
+}
+
 func (user *User) Create() error {
  return db.Create(&user).Error
 }
@@ -118,6 +133,17 @@ func (user *User) HasLiked(gist *Gist) (bool, error) {
  return true, nil
 }
 
+func (user *User) DeleteProviderID(provider string) error {
+ switch provider {
+ case "github":
+ return db.Model(&user).Update("github_id", nil).Error
+ case "gitea":
+ return db.Model(&user).Update("gitea_id", nil).Error
+ }
+
+ return nil
+}
+
 // -- DTO -- //
 
 type UserDTO struct {