README.md

@@ -71,7 +71,10 @@ Without systemd, `./kit.sh up` in binary mode runs Gitea in the background with
 | `DEFAULT_ALLOW_CREATE_ORGANIZATION` | `false` | new users cannot create organizations |
 | `MAX_CREATION_LIMIT` | `10` | repos per regular user (admins are exempt) |
 | `DISABLE_MIGRATIONS`, `[mirror] DISABLE_NEW_PULL` | `true` | no importing or mirroring from arbitrary URLs |
-| `[security] EGRESS_MODE` | `lax` | webhooks may call public hosts only, not your LAN or loopback |
+| `[security] ALLOWED_HOST_LIST` (`[webhook]` on Gitea 1.23) | `external` | webhooks may call public hosts only, not loopback, LAN or link-local |
+| `ENABLE_BASIC_AUTHENTICATION` | `false` | API and git-over-HTTP take tokens only; password basic auth is refused |
+| `[packages] ENABLED`, `[actions] ENABLED` | `false`, `false` | no package blobs, runner jobs or artifacts to fill the disk |
+| `[attachment] MAX_SIZE` / `MAX_FILES`, `[repository.upload] FILE_MAX_SIZE` / `MAX_FILES` | `4` MB / `3` | small uploads only |
 | `DEFAULT_KEEP_EMAIL_PRIVATE` | `true` | new users' emails hidden by default |
 | `DEFAULT_BRANCH` | `main` | |
 | `DISABLE_SSH` | `true` | Git over HTTPS with a token; nothing to expose but one HTTP port |
@@ -180,17 +183,42 @@ sign up and log in. Abuse is limited by what a new account can do, not by a chal
 
 - **Per-account caps:** `MAX_CREATION_LIMIT = 10` repos per user, and new users cannot create
   organizations.
-- **No pulling from arbitrary URLs:** migrations and new mirrors are off, so an account cannot make
+- **No server-side fetches into your network:** migrations and new mirrors are off, and
-  the server fetch from arbitrary URLs. `EGRESS_MODE = lax` keeps webhooks off your LAN and loopback.
+  `ALLOWED_HOST_LIST = external` (`[security]` on Gitea 28+, `[webhook]` on 1.23) keeps webhooks off loopback, private and link-local addresses.
+- **Tokens, not passwords, on the API:** `ENABLE_BASIC_AUTHENTICATION = false` refuses
+  username/password basic auth on the API and git-over-HTTP, so stolen or guessed passwords can't be
+  scripted against it. Personal access tokens (as header or as the basic-auth password) still work.
+  Note: Gitea's `POST /users/{name}/tokens` needs password basic auth, so mint tokens with
+  `kit.sh agent` (Gitea CLI) instead.
 - **Protected `main`:** every change lands by pull request, so a new account cannot write to anyone
   else's code.
 - **Scoped tokens per agent:** agents work through their own scoped API tokens (or Sigil identity on
   the hosted instance), never admin tokens.
-- **Registration switches:** `DISABLE_REGISTRATION=true` (invite-only) or `REGISTER_EMAIL_CONFIRM=true`
+- **Bounded storage:** packages and Actions are off; attachments and web uploads are capped at 4 MB,
-  (once `[mailer]` works) in `.env` if an instance is being flooded.
+  3 files. Also do the following outside Gitea:
-- **Edge rate limit (recommended):** a rate-limit rule at your proxy or CDN on `POST /user/sign_up`
+  - cap request bodies at your proxy (e.g. nginx `client_max_body_size 50m`; Cloudflare's free plan caps at 100 MB);
-  and `POST /user/login` (for example, a few requests per minute per IP). This slows bulk sign-up
+  - alert on disk use (e.g. a cron job that warns above 80% on the Gitea data volume);
-  without blocking any one bot. Gitea 1.23 has no built-in request rate limit.
+  - remove abusive accounts with `gitea admin user delete --purge --username NAME` (deletes their repos too).
+- **Registration switches** (in `.env` / `app.ini`):
+  - `DISABLE_REGISTRATION=true`: invite-only.
+  - `REGISTER_EMAIL_CONFIRM=true`: only once `[mailer]` works.
+  - `REGISTER_MANUAL_CONFIRM = true`: emergency switch that holds every new account until an admin
+    activates it.
+  - `[service] EMAIL_DOMAIN_ALLOWLIST` / `EMAIL_DOMAIN_BLOCKLIST`: restrict sign-up email domains.
+- **Edge rate limit:** a rate-limit rule at your proxy or CDN on `POST /user/sign_up` and
+  `POST /user/login` (for example, a few requests per minute per IP). Gitea 1.23 has no built-in
+  request rate limit.
+
+Known gaps:
+- The sign-up and password-reset forms reveal whether a username or email is taken (email
+  enumeration).
+- Names reserved by the hosted instance's `/join` flow are not reserved in Gitea itself.
+
+### Rollout order (existing instance with a captcha)
+
+1. Add the edge rate limit and verify it: a burst of `POST /user/sign_up` from one IP gets 429.
+2. Then set `ENABLE_CAPTCHA = false` (and the settings above) and restart Gitea.
+3. Rollback: set `ENABLE_CAPTCHA = true` and restart.
 
 ## Contributing
 

config/app.ini.template

@@ -49,10 +49,31 @@ SECRET_KEY = ${SECRET_KEY}
 INTERNAL_TOKEN = ${INTERNAL_TOKEN}
 MIN_PASSWORD_LENGTH = 10
 PASSWORD_CHECK_PWN = false
-; Outgoing requests (webhooks, OAuth2 clients) may reach public hosts only; loopback / LAN
+; Outgoing requests (webhooks etc.) may reach public hosts only: no loopback, private or
-; targets need an explicit [security] ALLOWED_HOST_LIST entry. Blocks SSRF into your network.
+; link-local addresses (SSRF guard). Gitea >= 28 reads this here; [webhook] ALLOWED_HOST_LIST is
-EGRESS_MODE = lax
+; deprecated there. On Gitea 1.23 put the same line under [webhook] instead.
+ALLOWED_HOST_LIST = external
 
+
+
+[packages]
+; Package registry off: no unbounded blob uploads.
+ENABLED = false
+
+[actions]
+; Actions off: no runner jobs or artifact storage.
+ENABLED = false
+
+[attachment]
+; Issue/PR attachments capped at 4 MB, 3 files per upload.
+ENABLED = true
+MAX_SIZE = 4
+MAX_FILES = 3
+
+[repository.upload]
+; Web-UI file uploads capped at 4 MB, 3 files.
+FILE_MAX_SIZE = 4
+MAX_FILES = 3
 [oauth2]
 JWT_SECRET = ${JWT_SECRET}
 
@@ -61,11 +82,15 @@ JWT_SECRET = ${JWT_SECRET}
 DISABLE_REGISTRATION = ${DISABLE_REGISTRATION}
 SHOW_REGISTRATION_BUTTON = true
 ; Agent-native: no captcha on sign-up or login. Abuse is limited by the per-user
-; defaults below (repo cap, no orgs, no migrations/mirrors, egress lax), not by a challenge.
+; defaults (repo cap, no orgs, no migrations/mirrors, webhooks to external hosts only,
+; no packages/Actions, small attachments, no password basic auth), not by a challenge.
 ENABLE_CAPTCHA = false
 REQUIRE_CAPTCHA_FOR_LOGIN = false
+; API and git-over-HTTP accept tokens only; password basic auth is refused.
+ENABLE_BASIC_AUTHENTICATION = false
 ; Only turn this on once [mailer] really delivers mail.
 REGISTER_EMAIL_CONFIRM = ${REGISTER_EMAIL_CONFIRM}
+; Emergency switch: set true to hold new sign-ups until an admin activates them.
 REGISTER_MANUAL_CONFIRM = false
 ALLOW_ONLY_EXTERNAL_REGISTRATION = false
 ; Public repos stay browsable without an account.

tests/e2e-binary.sh

@@ -40,7 +40,8 @@ H=(-H "Authorization: token $T" -H "Content-Type: application/json")
 curl -fsS "${H[@]}" -X POST "$A/user/repos" -d '{"name":"demo","auto_init":true,"default_branch":"main"}' >/dev/null && ok "admin created repo kitadmin/demo" || bad "create repo"
 ./kit.sh protect kitadmin/demo >/dev/null && ok "branch protection applied to main" || bad "protect"
 
-git -c credential.helper= clone -q "http://kitadmin:$P@127.0.0.1:$PORT/kitadmin/demo.git" "$CLONE"
+# Password basic auth is off (ENABLE_BASIC_AUTHENTICATION=false); git over HTTP uses the token.
+git -c credential.helper= clone -q "http://kitadmin:$T@127.0.0.1:$PORT/kitadmin/demo.git" "$CLONE"
 cd "$CLONE"; git config user.name e2e; git config user.email e2e@example.com
 echo direct > direct.txt; git add direct.txt; git commit -qm direct
 if git -c credential.helper= push -q origin main 2>/dev/null; then bad "direct push to main was ACCEPTED"; else ok "direct push to main rejected (even for the admin)"; fi
@@ -66,6 +67,31 @@ made=1; for i in $(seq 2 11); do
   [ "$c" = 201 ] && made=$((made+1))
 done
 [ "$made" = 10 ] && ok "repo limit: regular user stops at 10 repos" || bad "repo limit: user made $made repos"
+c=$(curl -s -o /dev/null -w '%{http_code}' -H "Authorization: token $AT" -H "Content-Type: application/json" -X POST "$A/user/repos" -d '{"name":"r-eleventh"}')
+[ "$c" = 403 ] && ok "11th repo refused (403)" || bad "11th repo: $c"
+
+# --- adversarial checks (agent-native sign-up, no captcha) ---
+c=$(curl -s -o /dev/null -w '%{http_code}' -u "kitadmin:$P" "$A/user"); [ "$c" = 401 ] && ok "password basic auth refused on the API (401)" || bad "password basic auth: $c"
+c=$(curl -s -o /dev/null -w '%{http_code}' -u "kitadmin:$T" "$A/user"); [ "$c" = 200 ] && ok "token as basic-auth password still works" || bad "token basic auth: $c"
+c=$(curl -s -o /dev/null -w '%{http_code}' -H "Authorization: token $T" "$A/user"); [ "$c" = 200 ] && ok "token header works" || bad "token header: $c"
+(cd "$CLONE" && git checkout -qb pw-push && if git -c credential.helper= push -q "http://kitadmin:$P@127.0.0.1:$PORT/kitadmin/demo.git" pw-push 2>/dev/null; then exit 1; fi) && ok "git push over HTTP refuses password basic auth" || bad "git HTTP push accepted a password"
+c=$(curl -s -o /dev/null -w '%{http_code}' -H "Authorization: token $AT" -H "Content-Type: application/json" -X POST "$A/orgs" -d '{"username":"e2e-org2"}'); [ "$c" = 403 ] && ok "agent token cannot create an org (403)" || bad "agent org create: $c"
+c=$(curl -s -o /dev/null -w '%{http_code}' -H "Authorization: token $AT" -X PUT --data-binary 'blob' "http://127.0.0.1:$PORT/api/packages/e2e-agent/generic/p/1.0/f.bin"); [ "$c" != 201 ] && ok "package upload refused ($c, registry off)" || bad "package upload accepted"
+LPORT=$((PORT+7)); HIT="$TMP/webhook-hit"
+python3 -c "import http.server,sys
+class H(http.server.BaseHTTPRequestHandler):
+    def do_POST(s): open(sys.argv[2],'w').write('hit'); s.send_response(200); s.end_headers()
+    def log_message(s,*a): pass
+http.server.HTTPServer(('127.0.0.1',int(sys.argv[1])),H).serve_forever()" "$LPORT" "$HIT" & LPID=$!
+sleep 0.5
+HID=$(curl -s -H "Authorization: token $AT" -H "Content-Type: application/json" -X POST "$A/repos/e2e-agent/agent-repo/hooks" \
+  -d "{\"type\":\"gitea\",\"active\":true,\"config\":{\"url\":\"http://127.0.0.1:$LPORT/\",\"content_type\":\"json\"}}" | python3 -c 'import json,sys;print(json.load(sys.stdin).get("id",""))' 2>/dev/null || true)
+[ -n "$HID" ] && ok "webhook to 127.0.0.1 created (id $HID); delivering test" || bad "webhook create failed"
+[ -n "$HID" ] && curl -s -o /dev/null -H "Authorization: token $AT" -X POST "$A/repos/e2e-agent/agent-repo/hooks/$HID/tests"
+sleep 4; kill $LPID 2>/dev/null || true
+[ ! -e "$HIT" ] && ok "webhook to 127.0.0.1 not delivered (ALLOWED_HOST_LIST=external)" || bad "webhook reached 127.0.0.1"
+grep -q 'not allowed\|blocked\|ALLOWED_HOST' "$TMP/home/log/"*.log 2>/dev/null && ok "Gitea logged the blocked webhook host" || echo "note: no block line found in the Gitea log (delivery absence is the check)"
+echo "PENDING  sign-up burst: throttling is the edge rate-limit rule (Cloudflare/proxy), not Gitea; test once the rule exists"
 if grep -q "Deprecation" "$TMP/home/log/gitea.out"; then bad "config uses deprecated keys: $(grep -o 'config option `[^`]*`' "$TMP/home/log/gitea.out" | sort -u | tr '\n' ' ')"; else ok "no deprecated config keys in the Gitea log"; fi
 
 echo; echo "$pass passed, $fail failed"