User password change (#280)

* start passwordChangeHandler

* add user scope

* add user module / api path

* add password change request

* make comment clearer

* add user to processor

* required true

* add processor call to handler

* don't pass tc or channel

* change password func + tests

* add some first docs about password management

* update swagger docs

* add api tests

* go fmt

* test fixes

docs/api/swagger.yaml

@@ -3362,6 +3362,51 @@ paths:
       summary: See public statuses/posts that your instance is aware of.
       tags:
       - timelines
+  /api/v1/user/password_change:
+    post:
+      consumes:
+      - application/json
+      - application/xml
+      - application/x-www-form-urlencoded
+      description: |-
+        The parameters can also be given in the body of the request, as JSON, if the content-type is set to 'application/json'.
+        The parameters can also be given in the body of the request, as XML, if the content-type is set to 'application/xml'.
+      operationId: userPasswordChange
+      parameters:
+      - description: User's previous password.
+        in: formData
+        name: old_password
+        required: true
+        type: string
+        x-go-name: OldPassword
+      - description: |-
+          Desired new password.
+          If the password does not have high enough entropy, it will be rejected.
+          See https://github.com/wagslane/go-password-validator
+        in: formData
+        name: new_password
+        required: true
+        type: string
+        x-go-name: NewPassword
+      produces:
+      - application/json
+      responses:
+        "200":
+          description: Change successful
+        "400":
+          description: bad request
+        "401":
+          description: unauthorized
+        "403":
+          description: forbidden
+        "500":
+          description: internal error
+      security:
+      - OAuth2 Bearer:
+        - write:user
+      summary: Change the password of authenticated user.
+      tags:
+      - user
   /users/{username}/statuses/{status}/replies:
     get:
       description: |-
@@ -3437,12 +3482,14 @@ securityDefinitions:
       read:search: grant read access to searches
       read:statuses: grants read access to statuses
       read:streaming: grants read access to streaming api
+      read:user: grants read access to user-level info
       write: grants write access to everything
       write:accounts: grants write access to accounts
       write:blocks: grants write access to blocks
       write:follows: grants write access to follows
       write:media: grants write access to media
       write:statuses: grants write access to statuses
+      write:user: grants write access to user-level info
     tokenUrl: https://example.org/oauth/token
     type: oauth2
 swagger: "2.0"

docs/swagger.go

@@ -40,12 +40,14 @@
 //           read:search: grant read access to searches
 //           read:statuses: grants read access to statuses
 //           read:streaming: grants read access to streaming api
+//           read:user: grants read access to user-level info
 //           write: grants write access to everything
 //           write:accounts: grants write access to accounts
 //           write:blocks: grants write access to blocks
 //           write:follows: grants write access to follows
 //           write:media: grants write access to media
 //           write:statuses: grants write access to statuses
+//           write:user: grants write access to user-level info
 //           admin: grants admin access to everything
 //           admin:accounts: grants admin access to accounts
 //       OAuth2 Application:

docs/user_guide/password_management.md

@@ -0,0 +1,19 @@
+# Password Management
+
+GoToSocial stores hashes of user passwords in its database using the secure [bcrypt](https://en.wikipedia.org/wiki/Bcrypt) function in the [Go standard libraries](https://pkg.go.dev/golang.org/x/crypto/bcrypt).
+
+This means that the plaintext value of your password is safe even if the database of your GoToSocial instance is compromised. It also means that your instance admin does not have access to your password.
+
+To check whether a password is sufficiently secure before accepting it, GoToSocial uses [this library](https://github.com/wagslane/go-password-validator) with entropy set to 60. This means that passwords like `password` are rejected, but something like `verylongandsecurepasswordhahaha` would be accepted, even without special characters/upper+lowercase etc.
+
+We recommend following the EFF's guidelines on [creating strong passwords](https://ssd.eff.org/en/module/creating-strong-passwords).
+
+## Change Your Password
+
+### API method
+
+If you are logged in (ie., you have a valid oauth token), you can change your password by making a POST request to `/api/v1/user/password_change`, using your token as authentication, and giving your old password and desired new password as parameters. Check the [API documentation](../api/swagger.md) for more details.
+
+## Reset Your Password
+
+todo