hetzner-infra/vpn, branch master

Re-enable IKE fragmentation (remove fragmentation=no)

2026-07-02T12:48:03+00:00

Android 12 IKEv2 may handle IKE-level fragments better than
IP-level fragmentation. iOS was failing with IKE fragmentation
previously (ECDSA cert era) — test if RSA cert + IKE fragmentation
now works for both platforms.

Co-Authored-By: Claude Sonnet 4.6

Force send ISRG Root X1 via local.cacerts for Android compat

2026-07-02T12:43:55+00:00

strongSwan skips self-signed root CAs from CERT payloads by default.
Setting cacerts = chain-3.crt in the local section forces it to include
ISRG Root X1 explicitly so Android 12 can complete trust chain validation.

Co-Authored-By: Claude Sonnet 4.6

Append issuer root CA to cert chain for Android IKEv2 compat

2026-07-02T12:35:37+00:00

Android 12 native IKEv2 requires the presented cert chain to include
a cert that is directly in the device trust store. Fetch the issuer
root CA (ISRG Root X1) via AIA from the last intermediate cert and
append it to server-chain.crt so strongSwan sends 4 CERT payloads:
Leaf + YR1 + Root YR + ISRG Root X1 (trusted on all Android versions).

Co-Authored-By: Claude Sonnet 4.6

Remove cert logic duplication from vpn/install.sh

2026-07-02T04:17:18+00:00

install.sh and renew-cert.sh had identical cert fetch/split code.
install.sh now delegates to renew-cert.sh, which in turn calls deploy.sh.
Flow: install.sh → renew-cert.sh → deploy.sh

Co-Authored-By: Claude Sonnet 4.6

Unify install.sh pattern: always delegate to deploy.sh

2026-07-02T04:14:11+00:00

Both hetzner-admin and vpn install.sh were calling docker compose
directly instead of going through their own deploy.sh, unlike mail
which already followed the correct pattern.

Co-Authored-By: Claude Sonnet 4.6

Send full cert chain to fix iOS IKEv2 validation

2026-07-02T01:15:30+00:00

iOS IKEv2 does not look up intermediates from the system trust store
(unlike TLS/HTTPS). Send all 3 certs: YE1 + Root YE + cross-signed
ISRG Root X2, so iOS can build the full chain through to ISRG Root X1.

Co-Authored-By: Claude Sonnet 4.6

Disable IKE fragmentation, use IP-level fragmentation for iOS

2026-07-01T15:52:49+00:00

iOS may have a bug where it advertises N(FRAG_SUP) but fails to reassemble
IKE fragments in IKE_AUTH responses. Switching to fragmentation=no forces
the large IKE_AUTH response to be sent as a single UDP packet with IP-level
fragmentation, which iOS's standard IP stack handles correctly.

Co-Authored-By: Claude Sonnet 4.6

Send only YE1+RootYE intermediates, skip cross-signed ISRG Root X2

2026-07-01T15:41:24+00:00

iOS 14+ and Android 11+ have ISRG Root X2 in their trust store.
Sending the cross-signed ISRG Root X2 alongside the trusted
self-signed version can confuse the cert path-building algorithm.

Chain: leaf -> YE1 -> Root YE -> [ISRG Root X2 from trust store]

Co-Authored-By: Claude Sonnet 4.6

Fix VPN cert chain: split multi-cert PEM for strongSwan

2026-07-01T15:28:31+00:00

Caddy's cert chain contains 4 certs:
  1. leaf (signed by YE1)
  2. YE1 (signed by Root YE)
  3. Root YE (cross-signed by ISRG Root X2)
  4. ISRG Root X2 (cross-signed by ISRG Root X1)

iOS/Android trust ISRG Root X1 but not Root YE directly.
The full cross-signed chain must be sent in IKE_AUTH.

strongSwan only reads the first cert from a multi-cert PEM file,
so entrypoint.sh now splits server-chain.crt into individual files
in x509ca/ before starting charon.

Co-Authored-By: Claude Sonnet 4.6

Restore intermediate cert + reduce IKE fragment size to 512 bytes

2026-07-01T15:21:40+00:00

iOS/Android VPN stacks don't follow AIA to download intermediate certs,
so YE1 must be sent by the server for cert chain validation.

The original 1236-byte IKE fragment was being dropped mid-path.
Setting fragment_size=512 splits the 1776-byte IKE_AUTH into ~4
fragments of ≤560 bytes each, which should traverse any NAT/router.

Co-Authored-By: Claude Sonnet 4.6