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How do I set a network interface to promiscuous mode in a kernel module?

I developed a kernel module to get all packets, bypass and ethernet interfaces.

Now I want, in my module, to set this interface to promiscuous mode. How can i do this?

I am getting an interface using dev_get_by_name (& init_net, "eth0") for struct net_device * dev.

Regards

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You can use the following function (which is in net / core / dev.c):

int dev_set_promiscuity(struct net_device *dev, int inc)


If you want to set the device in promiscuous mode, then it inc

should be 1. To disable the skipped mode, set inc

to -1. For the function to work, you need to block rtnl. To get it, you need to call the following functions before and after the call dev_set_promiscuity()

(functions found in net / core / rtnetlink.c):

void rtnl_lock(void);
void rtnl_unlock(void);
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Use dev_set_promiscuity()

. Use an increment of 1 to set the device to promiscuous mode, -1 to set it to non-promiscuous mode.



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When I use dev_set_promiscuity (dev_eth0,1) it appears in the dmesg command:

[550.411935] RTNL: Assertion failed to net / core / dev.c (4059)

[550.411940] Pid: 5164, comm: insmod Tainted: P 2.6.35101

[550.411943] Call trace:

[550.411951] []? printk + 0x25 / 0x29

[550.411956] [] __dev_set_promiscuity + 0x37 / 0x127

[550.411960] [] dev_set_promiscuity + 0x18 / 0x37

[550.411965] []? hook_init + 0x0 / 0x88 [nethook]

[550.411969] [] hook_init + 0x3a / 0x88 [nethook]

[550.411973] [] do_one_initcall + 0x4f / 0x139

[550.411978] []? blocking_notifier_call_chain + 0x11 / 0x13

[550.411982] [] sys_init_module + 0x7f / 0x19b

[550.411986] [] sysenter_do_call + 0x12 / 0x28

[550.411989] device eth0 entered promiscuous mode

RTNL: Assertion failed in net / core / dev.c (4059), this happens and after a while error messages and kernel crashes appear.

Does anyone know how to solve this? Regards

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