fix: use wall-clock time for the WireGuard handshake timestamp - #13
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wireguard_tai64n_now() used esp_timer_get_time() (uptime) for the TAI64N handshake-initiation timestamp. A peer keeps the greatest timestamp it has seen from us and rejects any handshake initiation whose timestamp is not greater (replay protection, WireGuard spec 5.1). With uptime, every reboot restarts the counter near zero, so a device that ran for hours cannot reconnect after a reboot until its new uptime passes the previous session's. Switch to gettimeofday() (wall-clock, expected to be set e.g. by SNTP before connecting). Also drops the now-unused esp_timer.h include. Adapted from CamM2325/microlink@6a4447c5 and CamM2325/microlink@a8d769e3 (this fix originated in the microlink monorepo before wireguard_lwip was split into its own submodule/repo). Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
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Picks up the TAI64N wall-clock handshake-timestamp fix (fugo101/wireguard-lwip#13, released as v1.0.1) for local/submodule builds. Registry-based builds already resolve it automatically via idf_component.yml's existing "^1.0.0" pin — no change needed there. Refs fugo101/wireguard-lwip#13 Co-authored-by: Adrian.Nguyen-Qualgo <nguyen.ndt@qualgo.net> Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>
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Summary
wireguard_tai64n_now()insrc/wireguard-platform-esp32.cusedesp_timer_get_time()(deviceuptime) for the TAI64N handshake-initiation timestamp. Per WireGuard's replay protection (spec
5.1), a peer keeps the greatest timestamp it has seen from us and rejects any handshake initiation
whose timestamp is not greater. With uptime as the source, every reboot restarts the counter near
zero — so a device that ran for hours cannot reconnect at all after a reboot, until its new uptime
happens to exceed the previous session's.
Fix: use
gettimeofday()(wall-clock time, expected to be SNTP-synced before connecting) instead.Also drops the now-unused
esp_timer.hinclude (confirmedesp_timer_get_time()was its only usein this file —
wireguard_sys_now()uses lwIP'ssys_now(), unaffected).Attribution
Adapted from
CamM2325/microlink@6a4447c5and
CamM2325/microlink@a8d769e3— thisfix originated in the
microlinkmonorepo beforewireguard_lwipwas split out into thisstandalone repo/submodule, as part of absorbing the bugfix/hardening subset of upstream
CamM2325/microlink#22(see
fugo101/microlink#44, already merged).Test plan
before merging.
wireguard_sys_now()untouched, confirmed noother use of
esp_timer_get_time()in this file.scenario this fix targets — a fresh boot needs the system clock set (SNTP) before the WG
handshake for the fix to take effect as intended.
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