MDD Sim Gateway v1.3.15
修复：经调制解调器桥接的线路可能无法注册
如果某条线路的 SIM 是通过 modem 桥（VPCD）访问的，重建引擎镜像后该线路可能再也注册不上，表现为每两分钟重建一次，而每次隧道都正常建立——因此故障看起来与出口节点无关，却也没有任何信息指向真正的原因。
起因是 1.3.13 引入的读卡器绑定校验。它读取 EF.ICCID 来确认"这个槽位里的卡确实属于本线路"，而这个读取调用没有超时。在 modem 桥的逻辑通道上，该读取不会失败，而是挂起——桥把多个通道复用到同一张物理 SIM，未接通的通道会让读取永远停住。三个组件都写了"卡不应答属于故障，而非换卡证据"的容错规则，但这条规则的前提是读取会返回。
本次修复两处，缺一不可：
- 所有读卡操作加上时限，让挂起变成各调用方本就会处理的"读不出"情形；
- 绑定校验改为在 SIM 桥启动时判定一次，不再每次鉴权都重做。运营商给整个鉴权交换只有三秒，在这个窗口内重复回答一个已有答案的问题，本身就足以让注册失败——只加超时而不挪位置，仍然会以"响应来得太晚"的方式失败。
校验对所有读卡器保持完整效力，modem 桥通道也不例外：两个外观相同、没有 USB 序列号的模块互换端口，正是这项校验存在的意义。
是否受影响
只有重建过引擎镜像的安装会遇到（全新安装，或手动强制重建）。自更新会保留现有引擎镜像，因此不会触及这一路径。使用物理读卡器的线路不受影响。
Fixed: a line reached through a modem bridge could stop registering
When a line's SIM is reached through a modem bridge (VPCD), rebuilding the engine image could leave that line unable to register — it rebuilt every couple of minutes with its tunnel established each time, so the failure looked unrelated to the exit node while nothing pointed at the actual cause.
The card-binding check added in 1.3.13 reads EF.ICCID to confirm the slot really holds this line's SIM, through a call that has no timeout. On a bridge channel that read does not fail — it hangs: the bridge multiplexes several channels onto one physical SIM, and a channel it has not wired up leaves the read parked forever. All three components implement a "a card that will not answer is a fault, not proof of a swap" rule, but that rule only applies once the read comes back.
Two changes, both required:
- Every card read is now bounded, turning the hang into the "could not read" case the existing handlers already cover.
- The binding question is settled once, when the SIM bridge starts, instead of on every authentication. The carrier allows three seconds for that whole exchange; re-answering a settled question inside it was enough to lose the registration on its own — bounding the read without moving it still failed, just as "the answer arrived after the carrier gave up".
The check keeps its full force on every reader, bridge channels included: two look-alike modems with no USB serial swapping ports is exactly the mix-up it exists to catch.
Who is affected
Only installations that rebuilt their engine image (a fresh install, or a manual forced rebuild). A self-update preserves the existing engine image and cannot reach this path. Lines on physical readers are unaffected.
Full Changelog: v1.3.14...v1.3.15