408e308ce5
2 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Hongming Wang
|
7658f56120 |
fix: close cross-tenant authz + cp_proxy admin-traversal gaps
Addresses three Critical findings from today's code review of the
SaaS-canvas routing stack.
## Critical-1: session verification scoped to the current tenant
session_auth.go previously verified via GET /cp/auth/me, which
only answers "is someone logged in" — NOT "is this user in the
org they're targeting." Every WorkOS-authed user (including folks
who only signed up via app.moleculesai.app with no tenant
relationship) could call /workspaces, /approvals/pending,
/bundles/import, /org/import etc. on ANY tenant they could reach.
Cross-tenant read: user at acme.moleculesai.app could hit
bob.moleculesai.app/workspaces with their cookie and get Bob's
workspaces.
Fix:
- CP gains GET /cp/auth/tenant-member?slug=<slug> which joins
org_members × organizations and only returns member:true when
the authenticated user is actually in that org.
- Tenant sets MOLECULE_ORG_SLUG at boot via user-data.
- session_auth now calls tenant-member (not /me), passing its
own slug. Cache key includes slug so one tenant's cached
positive never satisfies another's check.
## Critical-2: cp_proxy path allowlist (lateral-movement fix)
cp_proxy.go forwarded any /cp/* path upstream with the cookie
and bearer attached. Since /cp/admin/* accepts sessions as one
of its auth tiers, a tenant-authed user could curl
/cp/admin/tenants/other-slug/diagnostics through their tenant
and the CP would honor it — turning any tenant into a lateral
hop into admin surface.
Fix: explicit allowlist of paths the canvas browser bundle
actually needs (/cp/auth, /cp/orgs, /cp/billing, /cp/templates,
/cp/legal). Everything else 404s at the tenant before cookies
leave. Fail-closed: future UI paths require explicit entries.
## Important-1,2: bounded session cache + split positive/negative TTL
Previous sync.Map cache grew unbounded (one entry per unique
Cookie header for process lifetime) and cached failures for 30s,
meaning a 3s CP blip locked users out for the full window.
Fix:
- Bounded map with batch random eviction at cap (10k entries ×
~100 bytes = 1 MB ceiling). Random eviction is O(1)
expected; we don't need precise LRU.
- Periodic sweeper goroutine (2 min) reclaims expired entries
even when they're not re-hit.
- Positive TTL 30s, negative TTL 5s — short negative so CP
flakes self-heal fast.
- Transport errors NOT cached (would otherwise trap every
user during a multi-second upstream outage).
- Cache key = sha256(slug + cookie) so raw session tokens
don't sit in process memory, and cross-tenant isolation is
structural not policy.
## Important-3: TenantGuard /cp/* bypass documented
Added a security note to the bypass explaining why it's safe
only under the current setup (cp_proxy allowlist + tunnel-only
ingress), and what would require revisiting (SG opens :8080
inbound to the VPC).
## Tests
- session_auth_test.go: 12 new tests — empty cookie, missing
slug, no CP, member:true happy path with cache hit, member:
false, 401 upstream, malformed JSON, transport error not
cached, cross-tenant isolation (same cookie different
tenants hit upstream separately), bounded eviction, expired
entries, cache key collision resistance.
- cp_proxy_test.go: new — isCPProxyAllowedPath covers 17
allow/block cases, forwarding preserves Cookie+Auth, Host
rewritten, blocked paths 404 without calling upstream.
All platform tests pass. CP provisioner tests pass after
threading cfg.OrgSlug into the container env.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Hongming Wang
|
eb4f262d2a |
feat(router): /cp/* reverse-proxy to CP + same-origin canvas fetches
Canvas's browser bundle issues fetches to both CP endpoints
(/cp/auth/me, /cp/orgs, ...) AND tenant-platform endpoints
(/canvas/viewport, /approvals/pending, /org/templates). They
share ONE build-time base URL. Baking api.moleculesai.app
broke tenant calls with 404; baking the tenant subdomain broke
auth. Tried both today and saw exactly one failure mode per
attempt.
Real fix: same-origin fetches + tenant-side split. Adds:
internal/router/cp_proxy.go # /cp/* → CP_UPSTREAM_URL
mounted before NoRoute(canvasProxy). Now a tenant serves:
/cp/* → reverse-proxy to api.moleculesai.app
/canvas/viewport,
/approvals/pending,
/workspaces/:id/*,
/ws, /registry, → tenant platform (existing handlers)
/metrics
everything else → canvas UI (existing reverse-proxy)
Canvas middleware reverts to `connect-src 'self' wss:` for the
same-origin path (keeping explicit PLATFORM_URL whitelist as a
self-hosted escape hatch when the build-arg is non-empty).
CI build-arg flips to NEXT_PUBLIC_PLATFORM_URL="" so the bundle
issues relative fetches.
Security of cp_proxy:
- Cookie + Authorization PRESERVED across the hop (opposite of
canvas proxy) — they carry the WorkOS session, which is the
whole point.
- Host rewritten to upstream so CORS + cookie-domain on the CP
side see their own hostname.
- Upstream URL validated at construction: must parse, must be
http(s), must have a host — misconfig fails closed.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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