Subject: Re: [patch] d80211: fix WEP on big endian cpus

From: Michael Buesch <[email-masked]>
Date: Sun, 10 Sep 2006 20:11:47 +0200

On Sunday 10 September 2006 19:36, David Kimdon wrote:
> The ICV is transmitted on the network as a 4 byte little endian
> quantity.  WEP encryption needs to swap the bytes before transmission
> and decryption needs to swap bytes before ICV verification.

Holy shit, this fixes the bug I am hunting for hours at the moment!
I tested this patch and it works. Thanks very much, you saved me hours. ;)

John (Jiri), please apply this one.

Acked-by: Michael Buesch <[email-masked]>

> Index: wireless-dev/net/d80211/wep.c
> ===================================================================
> --- wireless-dev.orig/net/d80211/wep.c	2006-09-10 14:50:52.073583400 +0000
> +++ wireless-dev/net/d80211/wep.c	2006-09-10 14:51:10.146835848 +0000
> @@ -121,9 +121,11 @@
>  {
>  	struct scatterlist sg;
>  	u32 *icv;
> +	u32 crc;
>  
>  	icv = (u32 *)(data + data_len);
> -	*icv = ~crc32_le(~0, data, data_len);
> +	crc = ~crc32_le(~0, data, data_len);
> +	*icv = cpu_to_le32(crc);
>  
>  	crypto_cipher_setkey(tfm, rc4key, klen);
>  	sg.page = virt_to_page(data);
> @@ -196,6 +198,7 @@
>  	crypto_cipher_decrypt(tfm, &sg, &sg, sg.length);
>  
>  	crc = ~crc32_le(~0, data, data_len);
> +	crc = cpu_to_le32(crc);
>  	if (memcmp(&crc, data + data_len, WEP_ICV_LEN) != 0)
>  		/* ICV mismatch */
>  		return -1;
> 
> --
> -
> To unsubscribe from this list: send the line "unsubscribe netdev" in
> the body of a message to [email-masked]
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 

-- 
Greetings Michael.