Cyconet Blog

I was searching half a night and 2 hours today to get a Linksys Router working a wireless bridge with WPA(2) encryption. I tried Openwrt White Russian RC5 and DD-Wrt V23 SP1 and many combinations of WPA, WPA2, TKIP, AES. The bridge works well with WEP and without any encryption….

So … after more than one hour googling I found the following in the broadcom kernel module source:

if (val && strstr(v, "psk")) {
val = (strstr(v, "psk2") ? 0x84 : 0x4);
v = nvram_safe_get(wl_var("wpa_psk"));
if ((strlen(v) >= 8) && (strlen(v) < 63)) {

bcom_ioctl(skfd, ifname, WLC_SET_WPA_AUTH, &val, sizeof(val));

if (nvram_match(wl_var("mode"), "wet")) {
/* Enable in-driver WPA supplicant */
wsec_pmk_t pmk;

pmk.key_len = (unsigned short) strlen(v);
pmk.flags = WSEC_PASSPHRASE;
strcpy(pmk.key, v);
bcom_ioctl(skfd, ifname, WLC_SET_WSEC_PMK, &pmk, sizeof(pmk));
bcom_set_int(skfd, ifname, "sup_wpa", 1);
}
}
}

So … this means, that the WPA-PSK length has to be >= 8 and < 63, mine was 65. This wasn´t a problem yet, cause I used the routers only in AP mode, where this restriction doesn't effect. Shorting the WPA-PSK length 62 did the trick!

The Wireless Bridge and WPA(2) on Linksys Router … or how to look for a needle in a haystack by Cyconet Blog, unless otherwise expressly stated, is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 Unported License. Terms and conditions beyond the scope of this license may be available at blog.waja.info.