Security: add CSRF protection to login and setup forms#87
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vdaluz wants to merge 1 commit intosam1am:mainfrom
Open
Security: add CSRF protection to login and setup forms#87vdaluz wants to merge 1 commit intosam1am:mainfrom
vdaluz wants to merge 1 commit intosam1am:mainfrom
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Login and account creation forms had no CSRF tokens. A malicious page could submit these forms on behalf of an authenticated user. Uses itsdangerous URLSafeTimedSerializer (already a dependency) to generate signed, time-limited tokens embedded as hidden form fields. Tokens expire after 1 hour. Invalid or missing tokens return 403 with a fresh token so the user can retry immediately. Uses Starlette 1.0.0+ TemplateResponse API (request as first arg).
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Problem
The login and account setup forms have no CSRF tokens. A page on another origin could submit these forms on behalf of a visiting user (CSRF attack).
Fix
Uses
itsdangerous.URLSafeTimedSerializer— already a project dependency — to generate signed, time-limited tokens embedded as hidden form fields. Tokens are scoped with a separate salt (backlogia-csrf) from the session signer and expire after 1 hour.Invalid or missing tokens return 403 with a freshly generated token so the user can retry without reloading the page.
Changes
app_auth.py:_generate_csrf_token()and_validate_csrf_token()helpers; validation added toPOST /auth/loginandPOST /auth/setuplogin.html/setup.html: hiddencsrf_tokeninput added to both formsNote: uses Starlette 1.0.0+
TemplateResponseAPI (see PR #84).