Debian udev规则中的无条件转到（和Medion RC-0617）

我一直在逆向工程Medion RC-0617遥控器（带USB加密狗）在一些Debian 8.8衍生产品（antix16）下

它注册了3个不同的HID设备（/dev/hidraw*），我希望这些设备与/dev/mdremote0、1和2进行符号链接，与关联的hidraw设备的数量无关（大多数情况下是hidraw1、2和3，但这取决于插入的输入设备）以便使用脚本查询它们以执行遥控按钮的自定义操作。 （同时将其文件模式设置为666，以便作为普通用户访问）

udevadm info-a/dev/hidraw1的输出如下（缩短）：

因此，我需要编写的udev规则需要：

• 按idVendor和idProduct标识一个父设备
• 检查另一个父设备中的bInterfaceProtocol属性
• 为设备分配正确的符号链接/dev/mdremote*，并设置正确的权限

我的第一次尝试是这样的：

SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", ATTRS{bInterfaceProtocol}=="01", SYMLINK="mdremote0", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", ATTRS{bInterfaceProtocol}=="00", SYMLINK="mdremote1", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", ATTRS{bInterfaceProtocol}=="02", SYMLINK="mdremote2", MODE="0666"

SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", GOTO="match"
GOTO="end"
LABEL="match"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="01", SYMLINK="mdremote0", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="00", SYMLINK="mdremote1", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="02", SYMLINK="mdremote2", MODE="0666"
LABEL="end"

# Test if the wanted dongle is a parent device
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", GOTO="match"
# If not, skip the next 3 rules. The test against SUBSYSTEM=="hidraw" is there to produce a rule match
SUBSYSTEM=="hidraw", GOTO="end"
LABEL="match"
# Those 3 rules actually assign the right symlink depending on the bInterfaceProtocol property.
# Note that ALL of those rules contain the SUBSYSTEM=="hidraw" check, because the GOTO in the second line
# does not get executed for non-hidraw devices and the rules get evaluated for any non-hidraw device.
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="01", SYMLINK="mdremote0", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="00", SYMLINK="mdremote1", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="02", SYMLINK="mdremote2", MODE="0666"
LABEL="end"

（预期bInterfaceProtocol属性的顺序）

简而言之，这是行不通的，udev manpage说：

某些键还与父设备的属性相匹配 在sysfs中，不仅仅是生成事件的设备。如果 在单个设备中指定与父设备匹配的多个密钥 规则，所有这些密钥必须在同一个父设备上匹配

因此，我开始了另一种方法：首先对加密狗进行匹配，如果此检查不匹配，则跳过单个规则，如下所示：

SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", ATTRS{bInterfaceProtocol}=="01", SYMLINK="mdremote0", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", ATTRS{bInterfaceProtocol}=="00", SYMLINK="mdremote1", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", ATTRS{bInterfaceProtocol}=="02", SYMLINK="mdremote2", MODE="0666"

SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", GOTO="match"
GOTO="end"
LABEL="match"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="01", SYMLINK="mdremote0", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="00", SYMLINK="mdremote1", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="02", SYMLINK="mdremote2", MODE="0666"
LABEL="end"

# Test if the wanted dongle is a parent device
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", GOTO="match"
# If not, skip the next 3 rules. The test against SUBSYSTEM=="hidraw" is there to produce a rule match
SUBSYSTEM=="hidraw", GOTO="end"
LABEL="match"
# Those 3 rules actually assign the right symlink depending on the bInterfaceProtocol property.
# Note that ALL of those rules contain the SUBSYSTEM=="hidraw" check, because the GOTO in the second line
# does not get executed for non-hidraw devices and the rules get evaluated for any non-hidraw device.
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="01", SYMLINK="mdremote0", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="00", SYMLINK="mdremote1", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="02", SYMLINK="mdremote2", MODE="0666"
LABEL="end"

这在第一学期看起来是正确的。但是，猜猜看，它也不起作用，mdremote*符号链接只是指向任何设置了bInterfaceProtocol密钥的设备。

事实上，第二行（GOTO=“end”）被忽略了。我花了一些时间才弄明白，但解决办法其实很简单：

如果没有要匹配的条件，udev将规则视为“始终不匹配”，因此根本不执行GOTO

我的工作udev规则文件如下所示：

SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", ATTRS{bInterfaceProtocol}=="01", SYMLINK="mdremote0", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", ATTRS{bInterfaceProtocol}=="00", SYMLINK="mdremote1", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", ATTRS{bInterfaceProtocol}=="02", SYMLINK="mdremote2", MODE="0666"

SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", GOTO="match"
GOTO="end"
LABEL="match"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="01", SYMLINK="mdremote0", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="00", SYMLINK="mdremote1", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="02", SYMLINK="mdremote2", MODE="0666"
LABEL="end"

# Test if the wanted dongle is a parent device
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", GOTO="match"
# If not, skip the next 3 rules. The test against SUBSYSTEM=="hidraw" is there to produce a rule match
SUBSYSTEM=="hidraw", GOTO="end"
LABEL="match"
# Those 3 rules actually assign the right symlink depending on the bInterfaceProtocol property.
# Note that ALL of those rules contain the SUBSYSTEM=="hidraw" check, because the GOTO in the second line
# does not get executed for non-hidraw devices and the rules get evaluated for any non-hidraw device.
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="01", SYMLINK="mdremote0", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="00", SYMLINK="mdremote1", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="02", SYMLINK="mdremote2", MODE="0666"
LABEL="end"

结果证明这很有效。它仍然可以通过为GOTO=“end”语句提供更好的匹配规则来改进，但我没有这样做。

事实上，第二行（GOTO=“end”）被忽略了。我花了一些时间才弄明白，但解决办法其实很简单：

如果没有要匹配的条件，udev将规则视为“始终不匹配”，因此根本不执行GOTO

我的工作udev规则文件如下所示：

SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", ATTRS{bInterfaceProtocol}=="01", SYMLINK="mdremote0", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", ATTRS{bInterfaceProtocol}=="00", SYMLINK="mdremote1", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", ATTRS{bInterfaceProtocol}=="02", SYMLINK="mdremote2", MODE="0666"

SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", GOTO="match"
GOTO="end"
LABEL="match"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="01", SYMLINK="mdremote0", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="00", SYMLINK="mdremote1", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="02", SYMLINK="mdremote2", MODE="0666"
LABEL="end"

# Test if the wanted dongle is a parent device
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04f2", ATTRS{idProduct}=="0618", GOTO="match"
# If not, skip the next 3 rules. The test against SUBSYSTEM=="hidraw" is there to produce a rule match
SUBSYSTEM=="hidraw", GOTO="end"
LABEL="match"
# Those 3 rules actually assign the right symlink depending on the bInterfaceProtocol property.
# Note that ALL of those rules contain the SUBSYSTEM=="hidraw" check, because the GOTO in the second line
# does not get executed for non-hidraw devices and the rules get evaluated for any non-hidraw device.
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="01", SYMLINK="mdremote0", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="00", SYMLINK="mdremote1", MODE="0666"
SUBSYSTEM=="hidraw", SUBSYSTEMS=="usb", ATTRS{bInterfaceProtocol}=="02", SYMLINK="mdremote2", MODE="0666"
LABEL="end"

---

结果证明这很有效。它仍然可以通过为GOTO=“end”语句提供更好的匹配规则来改进，但我没有这样做。

@orwell我偶然发现了这一点，有点困惑为什么这对您不起作用。我尝试过做类似的事情，在无条件的GOTO和debian扩展以及Arch Linux上都没有问题。选中此项：

[c0d3@z3r0 tmp]$ cat /etc/udev/rules.d/45-test.rules
GOTO="end"
IMPORT{program}=="/bin/touch /tmp/noend"
LABEL="end"
IMPORT{program}=="/bin/touch /tmp/end"
[c0d3@z3r0 tmp]$ sudo udevadm control --reload 
[c0d3@z3r0 tmp]$ sudo udevadm trigger
[c0d3@z3r0 tmp]$ ls /tmp/*end
/tmp/end
[c0d3@z3r0 tmp]$ 

---

@奥威尔，我偶然发现了这一点，有点困惑为什么这对你不起作用。我尝试过做类似的事情，在无条件的GOTO和debian扩展以及Arch Linux上都没有问题。选中此项：

[c0d3@z3r0 tmp]$ cat /etc/udev/rules.d/45-test.rules
GOTO="end"
IMPORT{program}=="/bin/touch /tmp/noend"
LABEL="end"
IMPORT{program}=="/bin/touch /tmp/end"
[c0d3@z3r0 tmp]$ sudo udevadm control --reload 
[c0d3@z3r0 tmp]$ sudo udevadm trigger
[c0d3@z3r0 tmp]$ ls /tmp/*end
/tmp/end
[c0d3@z3r0 tmp]$ 

---

是的，听起来很有用。谢谢。是的，听起来很有用。谢谢。谢谢你发这个帖子！48小时过去了，所以你现在可以自己接受这个答案了。谢谢你发布这个！48小时过去了，所以你现在可以自己接受这个答案了。嗯，我已经写了一个不起作用的例子。。。但是我不想再摆弄这个了，谢谢，我已经写了一个不起作用的例子。。。但我不想再摆弄这个了，谢谢